drivers/regulator/core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 //
   3 // core.c  --  Voltage/Current Regulator framework.
   4 //
   5 // Copyright 2007, 2008 Wolfson Microelectronics PLC.
   6 // Copyright 2008 SlimLogic Ltd.
   7 //
   8 // Author: Liam Girdwood <[email protected]>
   9
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/device.h>
  14 #include <linux/slab.h>
  15 #include <linux/async.h>
  16 #include <linux/err.h>
  17 #include <linux/mutex.h>
  18 #include <linux/suspend.h>
  19 #include <linux/delay.h>
  20 #include <linux/gpio/consumer.h>
  21 #include <linux/of.h>
  22 #include <linux/regmap.h>
  23 #include <linux/regulator/of_regulator.h>
  24 #include <linux/regulator/consumer.h>
  25 #include <linux/regulator/coupler.h>
  26 #include <linux/regulator/driver.h>
  27 #include <linux/regulator/machine.h>
  28 #include <linux/module.h>
  29
  30 #define CREATE_TRACE_POINTS
  31 #include <trace/events/regulator.h>
  32
  33 #include "dummy.h"
  34 #include "internal.h"
  35
  36 static DEFINE_WW_CLASS(regulator_ww_class);
  37 static DEFINE_MUTEX(regulator_nesting_mutex);
  38 static DEFINE_MUTEX(regulator_list_mutex);
  39 static LIST_HEAD(regulator_map_list);
  40 static LIST_HEAD(regulator_ena_gpio_list);
  41 static LIST_HEAD(regulator_supply_alias_list);
  42 static LIST_HEAD(regulator_coupler_list);
  43 static bool has_full_constraints;
  44
  45 static struct dentry *debugfs_root;
  46
  47 /*
  48  * struct regulator_map
  49  *
  50  * Used to provide symbolic supply names to devices.
  51  */
  52 struct regulator_map {
  53         struct list_head list;
  54         const char *dev_name;   /* The dev_name() for the consumer */
  55         const char *supply;
  56         struct regulator_dev *regulator;
  57 };
  58
  59 /*
  60  * struct regulator_enable_gpio
  61  *
  62  * Management for shared enable GPIO pin
  63  */
  64 struct regulator_enable_gpio {
  65         struct list_head list;
  66         struct gpio_desc *gpiod;
  67         u32 enable_count;       /* a number of enabled shared GPIO */
  68         u32 request_count;      /* a number of requested shared GPIO */
  69 };
  70
  71 /*
  72  * struct regulator_supply_alias
  73  *
  74  * Used to map lookups for a supply onto an alternative device.
  75  */
  76 struct regulator_supply_alias {
  77         struct list_head list;
  78         struct device *src_dev;
  79         const char *src_supply;
  80         struct device *alias_dev;
  81         const char *alias_supply;
  82 };
  83
  84 static int _regulator_is_enabled(struct regulator_dev *rdev);
  85 static int _regulator_disable(struct regulator *regulator);
  86 static int _regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags);
  87 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  88 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  89 static int _notifier_call_chain(struct regulator_dev *rdev,
  90                                   unsigned long event, void *data);
  91 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
  92                                      int min_uV, int max_uV);
  93 static int regulator_balance_voltage(struct regulator_dev *rdev,
  94                                      suspend_state_t state);
  95 static struct regulator *create_regulator(struct regulator_dev *rdev,
  96                                           struct device *dev,
  97                                           const char *supply_name);
  98 static void destroy_regulator(struct regulator *regulator);
  99 static void _regulator_put(struct regulator *regulator);
 100
 101 const char *rdev_get_name(struct regulator_dev *rdev)
 102 {
 103         if (rdev->constraints && rdev->constraints->name)
 104                 return rdev->constraints->name;
 105         else if (rdev->desc->name)
 106                 return rdev->desc->name;
 107         else
 108                 return "";
 109 }
 110 EXPORT_SYMBOL_GPL(rdev_get_name);
 111
 112 static bool have_full_constraints(void)
 113 {
 114         return has_full_constraints || of_have_populated_dt();
 115 }
 116
 117 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
 118 {
 119         if (!rdev->constraints) {
 120                 rdev_err(rdev, "no constraints\n");
 121                 return false;
 122         }
 123
 124         if (rdev->constraints->valid_ops_mask & ops)
 125                 return true;
 126
 127         return false;
 128 }
 129
 130 /**
 131  * regulator_lock_nested - lock a single regulator
 132  * @rdev:               regulator source
 133  * @ww_ctx:             w/w mutex acquire context
 134  *
 135  * This function can be called many times by one task on
 136  * a single regulator and its mutex will be locked only
 137  * once. If a task, which is calling this function is other
 138  * than the one, which initially locked the mutex, it will
 139  * wait on mutex.
 140  */
 141 static inline int regulator_lock_nested(struct regulator_dev *rdev,
 142                                         struct ww_acquire_ctx *ww_ctx)
 143 {
 144         bool lock = false;
 145         int ret = 0;
 146
 147         mutex_lock(&regulator_nesting_mutex);
 148
 149         if (!ww_mutex_trylock(&rdev->mutex, ww_ctx)) {
 150                 if (rdev->mutex_owner == current)
 151                         rdev->ref_cnt++;
 152                 else
 153                         lock = true;
 154
 155                 if (lock) {
 156                         mutex_unlock(&regulator_nesting_mutex);
 157                         ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
 158                         mutex_lock(&regulator_nesting_mutex);
 159                 }
 160         } else {
 161                 lock = true;
 162         }
 163
 164         if (lock && ret != -EDEADLK) {
 165                 rdev->ref_cnt++;
 166                 rdev->mutex_owner = current;
 167         }
 168
 169         mutex_unlock(&regulator_nesting_mutex);
 170
 171         return ret;
 172 }
 173
 174 /**
 175  * regulator_lock - lock a single regulator
 176  * @rdev:               regulator source
 177  *
 178  * This function can be called many times by one task on
 179  * a single regulator and its mutex will be locked only
 180  * once. If a task, which is calling this function is other
 181  * than the one, which initially locked the mutex, it will
 182  * wait on mutex.
 183  */
 184 static void regulator_lock(struct regulator_dev *rdev)
 185 {
 186         regulator_lock_nested(rdev, NULL);
 187 }
 188
 189 /**
 190  * regulator_unlock - unlock a single regulator
 191  * @rdev:               regulator_source
 192  *
 193  * This function unlocks the mutex when the
 194  * reference counter reaches 0.
 195  */
 196 static void regulator_unlock(struct regulator_dev *rdev)
 197 {
 198         mutex_lock(&regulator_nesting_mutex);
 199
 200         if (--rdev->ref_cnt == 0) {
 201                 rdev->mutex_owner = NULL;
 202                 ww_mutex_unlock(&rdev->mutex);
 203         }
 204
 205         WARN_ON_ONCE(rdev->ref_cnt < 0);
 206
 207         mutex_unlock(&regulator_nesting_mutex);
 208 }
 209
 210 /**
 211  * regulator_lock_two - lock two regulators
 212  * @rdev1:              first regulator
 213  * @rdev2:              second regulator
 214  * @ww_ctx:             w/w mutex acquire context
 215  *
 216  * Locks both rdevs using the regulator_ww_class.
 217  */
 218 static void regulator_lock_two(struct regulator_dev *rdev1,
 219                                struct regulator_dev *rdev2,
 220                                struct ww_acquire_ctx *ww_ctx)
 221 {
 222         struct regulator_dev *held, *contended;
 223         int ret;
 224
 225         ww_acquire_init(ww_ctx, &regulator_ww_class);
 226
 227         /* Try to just grab both of them */
 228         ret = regulator_lock_nested(rdev1, ww_ctx);
 229         WARN_ON(ret);
 230         ret = regulator_lock_nested(rdev2, ww_ctx);
 231         if (ret != -EDEADLOCK) {
 232                 WARN_ON(ret);
 233                 goto exit;
 234         }
 235
 236         held = rdev1;
 237         contended = rdev2;
 238         while (true) {
 239                 regulator_unlock(held);
 240
 241                 ww_mutex_lock_slow(&contended->mutex, ww_ctx);
 242                 contended->ref_cnt++;
 243                 contended->mutex_owner = current;
 244                 swap(held, contended);
 245                 ret = regulator_lock_nested(contended, ww_ctx);
 246
 247                 if (ret != -EDEADLOCK) {
 248                         WARN_ON(ret);
 249                         break;
 250                 }
 251         }
 252
 253 exit:
 254         ww_acquire_done(ww_ctx);
 255 }
 256
 257 /**
 258  * regulator_unlock_two - unlock two regulators
 259  * @rdev1:              first regulator
 260  * @rdev2:              second regulator
 261  * @ww_ctx:             w/w mutex acquire context
 262  *
 263  * The inverse of regulator_lock_two().
 264  */
 265
 266 static void regulator_unlock_two(struct regulator_dev *rdev1,
 267                                  struct regulator_dev *rdev2,
 268                                  struct ww_acquire_ctx *ww_ctx)
 269 {
 270         regulator_unlock(rdev2);
 271         regulator_unlock(rdev1);
 272         ww_acquire_fini(ww_ctx);
 273 }
 274
 275 static bool regulator_supply_is_couple(struct regulator_dev *rdev)
 276 {
 277         struct regulator_dev *c_rdev;
 278         int i;
 279
 280         for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
 281                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 282
 283                 if (rdev->supply->rdev == c_rdev)
 284                         return true;
 285         }
 286
 287         return false;
 288 }
 289
 290 static void regulator_unlock_recursive(struct regulator_dev *rdev,
 291                                        unsigned int n_coupled)
 292 {
 293         struct regulator_dev *c_rdev, *supply_rdev;
 294         int i, supply_n_coupled;
 295
 296         for (i = n_coupled; i > 0; i--) {
 297                 c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
 298
 299                 if (!c_rdev)
 300                         continue;
 301
 302                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 303                         supply_rdev = c_rdev->supply->rdev;
 304                         supply_n_coupled = supply_rdev->coupling_desc.n_coupled;
 305
 306                         regulator_unlock_recursive(supply_rdev,
 307                                                    supply_n_coupled);
 308                 }
 309
 310                 regulator_unlock(c_rdev);
 311         }
 312 }
 313
 314 static int regulator_lock_recursive(struct regulator_dev *rdev,
 315                                     struct regulator_dev **new_contended_rdev,
 316                                     struct regulator_dev **old_contended_rdev,
 317                                     struct ww_acquire_ctx *ww_ctx)
 318 {
 319         struct regulator_dev *c_rdev;
 320         int i, err;
 321
 322         for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
 323                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 324
 325                 if (!c_rdev)
 326                         continue;
 327
 328                 if (c_rdev != *old_contended_rdev) {
 329                         err = regulator_lock_nested(c_rdev, ww_ctx);
 330                         if (err) {
 331                                 if (err == -EDEADLK) {
 332                                         *new_contended_rdev = c_rdev;
 333                                         goto err_unlock;
 334                                 }
 335
 336                                 /* shouldn't happen */
 337                                 WARN_ON_ONCE(err != -EALREADY);
 338                         }
 339                 } else {
 340                         *old_contended_rdev = NULL;
 341                 }
 342
 343                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 344                         err = regulator_lock_recursive(c_rdev->supply->rdev,
 345                                                        new_contended_rdev,
 346                                                        old_contended_rdev,
 347                                                        ww_ctx);
 348                         if (err) {
 349                                 regulator_unlock(c_rdev);
 350                                 goto err_unlock;
 351                         }
 352                 }
 353         }
 354
 355         return 0;
 356
 357 err_unlock:
 358         regulator_unlock_recursive(rdev, i);
 359
 360         return err;
 361 }
 362
 363 /**
 364  * regulator_unlock_dependent - unlock regulator's suppliers and coupled
 365  *                              regulators
 366  * @rdev:                       regulator source
 367  * @ww_ctx:                     w/w mutex acquire context
 368  *
 369  * Unlock all regulators related with rdev by coupling or supplying.
 370  */
 371 static void regulator_unlock_dependent(struct regulator_dev *rdev,
 372                                        struct ww_acquire_ctx *ww_ctx)
 373 {
 374         regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
 375         ww_acquire_fini(ww_ctx);
 376 }
 377
 378 /**
 379  * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
 380  * @rdev:                       regulator source
 381  * @ww_ctx:                     w/w mutex acquire context
 382  *
 383  * This function as a wrapper on regulator_lock_recursive(), which locks
 384  * all regulators related with rdev by coupling or supplying.
 385  */
 386 static void regulator_lock_dependent(struct regulator_dev *rdev,
 387                                      struct ww_acquire_ctx *ww_ctx)
 388 {
 389         struct regulator_dev *new_contended_rdev = NULL;
 390         struct regulator_dev *old_contended_rdev = NULL;
 391         int err;
 392
 393         mutex_lock(&regulator_list_mutex);
 394
 395         ww_acquire_init(ww_ctx, &regulator_ww_class);
 396
 397         do {
 398                 if (new_contended_rdev) {
 399                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
 400                         old_contended_rdev = new_contended_rdev;
 401                         old_contended_rdev->ref_cnt++;
 402                         old_contended_rdev->mutex_owner = current;
 403                 }
 404
 405                 err = regulator_lock_recursive(rdev,
 406                                                &new_contended_rdev,
 407                                                &old_contended_rdev,
 408                                                ww_ctx);
 409
 410                 if (old_contended_rdev)
 411                         regulator_unlock(old_contended_rdev);
 412
 413         } while (err == -EDEADLK);
 414
 415         ww_acquire_done(ww_ctx);
 416
 417         mutex_unlock(&regulator_list_mutex);
 418 }
 419
 420 /**
 421  * of_get_child_regulator - get a child regulator device node
 422  * based on supply name
 423  * @parent: Parent device node
 424  * @prop_name: Combination regulator supply name and "-supply"
 425  *
 426  * Traverse all child nodes.
 427  * Extract the child regulator device node corresponding to the supply name.
 428  * returns the device node corresponding to the regulator if found, else
 429  * returns NULL.
 430  */
 431 static struct device_node *of_get_child_regulator(struct device_node *parent,
 432                                                   const char *prop_name)
 433 {
 434         struct device_node *regnode = NULL;
 435         struct device_node *child = NULL;
 436
 437         for_each_child_of_node(parent, child) {
 438                 regnode = of_parse_phandle(child, prop_name, 0);
 439
 440                 if (!regnode) {
 441                         regnode = of_get_child_regulator(child, prop_name);
 442                         if (regnode)
 443                                 goto err_node_put;
 444                 } else {
 445                         goto err_node_put;
 446                 }
 447         }
 448         return NULL;
 449
 450 err_node_put:
 451         of_node_put(child);
 452         return regnode;
 453 }
 454
 455 /**
 456  * of_get_regulator - get a regulator device node based on supply name
 457  * @dev: Device pointer for the consumer (of regulator) device
 458  * @supply: regulator supply name
 459  *
 460  * Extract the regulator device node corresponding to the supply name.
 461  * returns the device node corresponding to the regulator if found, else
 462  * returns NULL.
 463  */
 464 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 465 {
 466         struct device_node *regnode = NULL;
 467         char prop_name[64]; /* 64 is max size of property name */
 468
 469         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 470
 471         snprintf(prop_name, 64, "%s-supply", supply);
 472         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 473
 474         if (!regnode) {
 475                 regnode = of_get_child_regulator(dev->of_node, prop_name);
 476                 if (regnode)
 477                         return regnode;
 478
 479                 dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
 480                                 prop_name, dev->of_node);
 481                 return NULL;
 482         }
 483         return regnode;
 484 }
 485
 486 /* Platform voltage constraint check */
 487 int regulator_check_voltage(struct regulator_dev *rdev,
 488                             int *min_uV, int *max_uV)
 489 {
 490         BUG_ON(*min_uV > *max_uV);
 491
 492         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
 493                 rdev_err(rdev, "voltage operation not allowed\n");
 494                 return -EPERM;
 495         }
 496
 497         if (*max_uV > rdev->constraints->max_uV)
 498                 *max_uV = rdev->constraints->max_uV;
 499         if (*min_uV < rdev->constraints->min_uV)
 500                 *min_uV = rdev->constraints->min_uV;
 501
 502         if (*min_uV > *max_uV) {
 503                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 504                          *min_uV, *max_uV);
 505                 return -EINVAL;
 506         }
 507
 508         return 0;
 509 }
 510
 511 /* return 0 if the state is valid */
 512 static int regulator_check_states(suspend_state_t state)
 513 {
 514         return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
 515 }
 516
 517 /* Make sure we select a voltage that suits the needs of all
 518  * regulator consumers
 519  */
 520 int regulator_check_consumers(struct regulator_dev *rdev,
 521                               int *min_uV, int *max_uV,
 522                               suspend_state_t state)
 523 {
 524         struct regulator *regulator;
 525         struct regulator_voltage *voltage;
 526
 527         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 528                 voltage = &regulator->voltage[state];
 529                 /*
 530                  * Assume consumers that didn't say anything are OK
 531                  * with anything in the constraint range.
 532                  */
 533                 if (!voltage->min_uV && !voltage->max_uV)
 534                         continue;
 535
 536                 if (*max_uV > voltage->max_uV)
 537                         *max_uV = voltage->max_uV;
 538                 if (*min_uV < voltage->min_uV)
 539                         *min_uV = voltage->min_uV;
 540         }
 541
 542         if (*min_uV > *max_uV) {
 543                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
 544                         *min_uV, *max_uV);
 545                 return -EINVAL;
 546         }
 547
 548         return 0;
 549 }
 550
 551 /* current constraint check */
 552 static int regulator_check_current_limit(struct regulator_dev *rdev,
 553                                         int *min_uA, int *max_uA)
 554 {
 555         BUG_ON(*min_uA > *max_uA);
 556
 557         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
 558                 rdev_err(rdev, "current operation not allowed\n");
 559                 return -EPERM;
 560         }
 561
 562         if (*max_uA > rdev->constraints->max_uA)
 563                 *max_uA = rdev->constraints->max_uA;
 564         if (*min_uA < rdev->constraints->min_uA)
 565                 *min_uA = rdev->constraints->min_uA;
 566
 567         if (*min_uA > *max_uA) {
 568                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 569                          *min_uA, *max_uA);
 570                 return -EINVAL;
 571         }
 572
 573         return 0;
 574 }
 575
 576 /* operating mode constraint check */
 577 static int regulator_mode_constrain(struct regulator_dev *rdev,
 578                                     unsigned int *mode)
 579 {
 580         switch (*mode) {
 581         case REGULATOR_MODE_FAST:
 582         case REGULATOR_MODE_NORMAL:
 583         case REGULATOR_MODE_IDLE:
 584         case REGULATOR_MODE_STANDBY:
 585                 break;
 586         default:
 587                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 588                 return -EINVAL;
 589         }
 590
 591         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
 592                 rdev_err(rdev, "mode operation not allowed\n");
 593                 return -EPERM;
 594         }
 595
 596         /* The modes are bitmasks, the most power hungry modes having
 597          * the lowest values. If the requested mode isn't supported
 598          * try higher modes.
 599          */
 600         while (*mode) {
 601                 if (rdev->constraints->valid_modes_mask & *mode)
 602                         return 0;
 603                 *mode /= 2;
 604         }
 605
 606         return -EINVAL;
 607 }
 608
 609 static inline struct regulator_state *
 610 regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
 611 {
 612         if (rdev->constraints == NULL)
 613                 return NULL;
 614
 615         switch (state) {
 616         case PM_SUSPEND_STANDBY:
 617                 return &rdev->constraints->state_standby;
 618         case PM_SUSPEND_MEM:
 619                 return &rdev->constraints->state_mem;
 620         case PM_SUSPEND_MAX:
 621                 return &rdev->constraints->state_disk;
 622         default:
 623                 return NULL;
 624         }
 625 }
 626
 627 static const struct regulator_state *
 628 regulator_get_suspend_state_check(struct regulator_dev *rdev, suspend_state_t state)
 629 {
 630         const struct regulator_state *rstate;
 631
 632         rstate = regulator_get_suspend_state(rdev, state);
 633         if (rstate == NULL)
 634                 return NULL;
 635
 636         /* If we have no suspend mode configuration don't set anything;
 637          * only warn if the driver implements set_suspend_voltage or
 638          * set_suspend_mode callback.
 639          */
 640         if (rstate->enabled != ENABLE_IN_SUSPEND &&
 641             rstate->enabled != DISABLE_IN_SUSPEND) {
 642                 if (rdev->desc->ops->set_suspend_voltage ||
 643                     rdev->desc->ops->set_suspend_mode)
 644                         rdev_warn(rdev, "No configuration\n");
 645                 return NULL;
 646         }
 647
 648         return rstate;
 649 }
 650
 651 static ssize_t microvolts_show(struct device *dev,
 652                                struct device_attribute *attr, char *buf)
 653 {
 654         struct regulator_dev *rdev = dev_get_drvdata(dev);
 655         int uV;
 656
 657         regulator_lock(rdev);
 658         uV = regulator_get_voltage_rdev(rdev);
 659         regulator_unlock(rdev);
 660
 661         if (uV < 0)
 662                 return uV;
 663         return sprintf(buf, "%d\n", uV);
 664 }
 665 static DEVICE_ATTR_RO(microvolts);
 666
 667 static ssize_t microamps_show(struct device *dev,
 668                               struct device_attribute *attr, char *buf)
 669 {
 670         struct regulator_dev *rdev = dev_get_drvdata(dev);
 671
 672         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 673 }
 674 static DEVICE_ATTR_RO(microamps);
 675
 676 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 677                          char *buf)
 678 {
 679         struct regulator_dev *rdev = dev_get_drvdata(dev);
 680
 681         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 682 }
 683 static DEVICE_ATTR_RO(name);
 684
 685 static const char *regulator_opmode_to_str(int mode)
 686 {
 687         switch (mode) {
 688         case REGULATOR_MODE_FAST:
 689                 return "fast";
 690         case REGULATOR_MODE_NORMAL:
 691                 return "normal";
 692         case REGULATOR_MODE_IDLE:
 693                 return "idle";
 694         case REGULATOR_MODE_STANDBY:
 695                 return "standby";
 696         }
 697         return "unknown";
 698 }
 699
 700 static ssize_t regulator_print_opmode(char *buf, int mode)
 701 {
 702         return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
 703 }
 704
 705 static ssize_t opmode_show(struct device *dev,
 706                            struct device_attribute *attr, char *buf)
 707 {
 708         struct regulator_dev *rdev = dev_get_drvdata(dev);
 709
 710         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 711 }
 712 static DEVICE_ATTR_RO(opmode);
 713
 714 static ssize_t regulator_print_state(char *buf, int state)
 715 {
 716         if (state > 0)
 717                 return sprintf(buf, "enabled\n");
 718         else if (state == 0)
 719                 return sprintf(buf, "disabled\n");
 720         else
 721                 return sprintf(buf, "unknown\n");
 722 }
 723
 724 static ssize_t state_show(struct device *dev,
 725                           struct device_attribute *attr, char *buf)
 726 {
 727         struct regulator_dev *rdev = dev_get_drvdata(dev);
 728         ssize_t ret;
 729
 730         regulator_lock(rdev);
 731         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 732         regulator_unlock(rdev);
 733
 734         return ret;
 735 }
 736 static DEVICE_ATTR_RO(state);
 737
 738 static ssize_t status_show(struct device *dev,
 739                            struct device_attribute *attr, char *buf)
 740 {
 741         struct regulator_dev *rdev = dev_get_drvdata(dev);
 742         int status;
 743         char *label;
 744
 745         status = rdev->desc->ops->get_status(rdev);
 746         if (status < 0)
 747                 return status;
 748
 749         switch (status) {
 750         case REGULATOR_STATUS_OFF:
 751                 label = "off";
 752                 break;
 753         case REGULATOR_STATUS_ON:
 754                 label = "on";
 755                 break;
 756         case REGULATOR_STATUS_ERROR:
 757                 label = "error";
 758                 break;
 759         case REGULATOR_STATUS_FAST:
 760                 label = "fast";
 761                 break;
 762         case REGULATOR_STATUS_NORMAL:
 763                 label = "normal";
 764                 break;
 765         case REGULATOR_STATUS_IDLE:
 766                 label = "idle";
 767                 break;
 768         case REGULATOR_STATUS_STANDBY:
 769                 label = "standby";
 770                 break;
 771         case REGULATOR_STATUS_BYPASS:
 772                 label = "bypass";
 773                 break;
 774         case REGULATOR_STATUS_UNDEFINED:
 775                 label = "undefined";
 776                 break;
 777         default:
 778                 return -ERANGE;
 779         }
 780
 781         return sprintf(buf, "%s\n", label);
 782 }
 783 static DEVICE_ATTR_RO(status);
 784
 785 static ssize_t min_microamps_show(struct device *dev,
 786                                   struct device_attribute *attr, char *buf)
 787 {
 788         struct regulator_dev *rdev = dev_get_drvdata(dev);
 789
 790         if (!rdev->constraints)
 791                 return sprintf(buf, "constraint not defined\n");
 792
 793         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 794 }
 795 static DEVICE_ATTR_RO(min_microamps);
 796
 797 static ssize_t max_microamps_show(struct device *dev,
 798                                   struct device_attribute *attr, char *buf)
 799 {
 800         struct regulator_dev *rdev = dev_get_drvdata(dev);
 801
 802         if (!rdev->constraints)
 803                 return sprintf(buf, "constraint not defined\n");
 804
 805         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 806 }
 807 static DEVICE_ATTR_RO(max_microamps);
 808
 809 static ssize_t min_microvolts_show(struct device *dev,
 810                                    struct device_attribute *attr, char *buf)
 811 {
 812         struct regulator_dev *rdev = dev_get_drvdata(dev);
 813
 814         if (!rdev->constraints)
 815                 return sprintf(buf, "constraint not defined\n");
 816
 817         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 818 }
 819 static DEVICE_ATTR_RO(min_microvolts);
 820
 821 static ssize_t max_microvolts_show(struct device *dev,
 822                                    struct device_attribute *attr, char *buf)
 823 {
 824         struct regulator_dev *rdev = dev_get_drvdata(dev);
 825
 826         if (!rdev->constraints)
 827                 return sprintf(buf, "constraint not defined\n");
 828
 829         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 830 }
 831 static DEVICE_ATTR_RO(max_microvolts);
 832
 833 static ssize_t requested_microamps_show(struct device *dev,
 834                                         struct device_attribute *attr, char *buf)
 835 {
 836         struct regulator_dev *rdev = dev_get_drvdata(dev);
 837         struct regulator *regulator;
 838         int uA = 0;
 839
 840         regulator_lock(rdev);
 841         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 842                 if (regulator->enable_count)
 843                         uA += regulator->uA_load;
 844         }
 845         regulator_unlock(rdev);
 846         return sprintf(buf, "%d\n", uA);
 847 }
 848 static DEVICE_ATTR_RO(requested_microamps);
 849
 850 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
 851                               char *buf)
 852 {
 853         struct regulator_dev *rdev = dev_get_drvdata(dev);
 854         return sprintf(buf, "%d\n", rdev->use_count);
 855 }
 856 static DEVICE_ATTR_RO(num_users);
 857
 858 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 859                          char *buf)
 860 {
 861         struct regulator_dev *rdev = dev_get_drvdata(dev);
 862
 863         switch (rdev->desc->type) {
 864         case REGULATOR_VOLTAGE:
 865                 return sprintf(buf, "voltage\n");
 866         case REGULATOR_CURRENT:
 867                 return sprintf(buf, "current\n");
 868         }
 869         return sprintf(buf, "unknown\n");
 870 }
 871 static DEVICE_ATTR_RO(type);
 872
 873 static ssize_t suspend_mem_microvolts_show(struct device *dev,
 874                                            struct device_attribute *attr, char *buf)
 875 {
 876         struct regulator_dev *rdev = dev_get_drvdata(dev);
 877
 878         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 879 }
 880 static DEVICE_ATTR_RO(suspend_mem_microvolts);
 881
 882 static ssize_t suspend_disk_microvolts_show(struct device *dev,
 883                                             struct device_attribute *attr, char *buf)
 884 {
 885         struct regulator_dev *rdev = dev_get_drvdata(dev);
 886
 887         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 888 }
 889 static DEVICE_ATTR_RO(suspend_disk_microvolts);
 890
 891 static ssize_t suspend_standby_microvolts_show(struct device *dev,
 892                                                struct device_attribute *attr, char *buf)
 893 {
 894         struct regulator_dev *rdev = dev_get_drvdata(dev);
 895
 896         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 897 }
 898 static DEVICE_ATTR_RO(suspend_standby_microvolts);
 899
 900 static ssize_t suspend_mem_mode_show(struct device *dev,
 901                                      struct device_attribute *attr, char *buf)
 902 {
 903         struct regulator_dev *rdev = dev_get_drvdata(dev);
 904
 905         return regulator_print_opmode(buf,
 906                 rdev->constraints->state_mem.mode);
 907 }
 908 static DEVICE_ATTR_RO(suspend_mem_mode);
 909
 910 static ssize_t suspend_disk_mode_show(struct device *dev,
 911                                       struct device_attribute *attr, char *buf)
 912 {
 913         struct regulator_dev *rdev = dev_get_drvdata(dev);
 914
 915         return regulator_print_opmode(buf,
 916                 rdev->constraints->state_disk.mode);
 917 }
 918 static DEVICE_ATTR_RO(suspend_disk_mode);
 919
 920 static ssize_t suspend_standby_mode_show(struct device *dev,
 921                                          struct device_attribute *attr, char *buf)
 922 {
 923         struct regulator_dev *rdev = dev_get_drvdata(dev);
 924
 925         return regulator_print_opmode(buf,
 926                 rdev->constraints->state_standby.mode);
 927 }
 928 static DEVICE_ATTR_RO(suspend_standby_mode);
 929
 930 static ssize_t suspend_mem_state_show(struct device *dev,
 931                                       struct device_attribute *attr, char *buf)
 932 {
 933         struct regulator_dev *rdev = dev_get_drvdata(dev);
 934
 935         return regulator_print_state(buf,
 936                         rdev->constraints->state_mem.enabled);
 937 }
 938 static DEVICE_ATTR_RO(suspend_mem_state);
 939
 940 static ssize_t suspend_disk_state_show(struct device *dev,
 941                                        struct device_attribute *attr, char *buf)
 942 {
 943         struct regulator_dev *rdev = dev_get_drvdata(dev);
 944
 945         return regulator_print_state(buf,
 946                         rdev->constraints->state_disk.enabled);
 947 }
 948 static DEVICE_ATTR_RO(suspend_disk_state);
 949
 950 static ssize_t suspend_standby_state_show(struct device *dev,
 951                                           struct device_attribute *attr, char *buf)
 952 {
 953         struct regulator_dev *rdev = dev_get_drvdata(dev);
 954
 955         return regulator_print_state(buf,
 956                         rdev->constraints->state_standby.enabled);
 957 }
 958 static DEVICE_ATTR_RO(suspend_standby_state);
 959
 960 static ssize_t bypass_show(struct device *dev,
 961                            struct device_attribute *attr, char *buf)
 962 {
 963         struct regulator_dev *rdev = dev_get_drvdata(dev);
 964         const char *report;
 965         bool bypass;
 966         int ret;
 967
 968         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
 969
 970         if (ret != 0)
 971                 report = "unknown";
 972         else if (bypass)
 973                 report = "enabled";
 974         else
 975                 report = "disabled";
 976
 977         return sprintf(buf, "%s\n", report);
 978 }
 979 static DEVICE_ATTR_RO(bypass);
 980
 981 #define REGULATOR_ERROR_ATTR(name, bit)                                                 \
 982         static ssize_t name##_show(struct device *dev, struct device_attribute *attr,   \
 983                                    char *buf)                                           \
 984         {                                                                               \
 985                 int ret;                                                                \
 986                 unsigned int flags;                                                     \
 987                 struct regulator_dev *rdev = dev_get_drvdata(dev);                      \
 988                 ret = _regulator_get_error_flags(rdev, &flags);                         \
 989                 if (ret)                                                                \
 990                         return ret;                                                     \
 991                 return sysfs_emit(buf, "%d\n", !!(flags & (bit)));                      \
 992         }                                                                               \
 993         static DEVICE_ATTR_RO(name)
 994
 995 REGULATOR_ERROR_ATTR(under_voltage, REGULATOR_ERROR_UNDER_VOLTAGE);
 996 REGULATOR_ERROR_ATTR(over_current, REGULATOR_ERROR_OVER_CURRENT);
 997 REGULATOR_ERROR_ATTR(regulation_out, REGULATOR_ERROR_REGULATION_OUT);
 998 REGULATOR_ERROR_ATTR(fail, REGULATOR_ERROR_FAIL);
 999 REGULATOR_ERROR_ATTR(over_temp, REGULATOR_ERROR_OVER_TEMP);
1000 REGULATOR_ERROR_ATTR(under_voltage_warn, REGULATOR_ERROR_UNDER_VOLTAGE_WARN);
1001 REGULATOR_ERROR_ATTR(over_current_warn, REGULATOR_ERROR_OVER_CURRENT_WARN);
1002 REGULATOR_ERROR_ATTR(over_voltage_warn, REGULATOR_ERROR_OVER_VOLTAGE_WARN);
1003 REGULATOR_ERROR_ATTR(over_temp_warn, REGULATOR_ERROR_OVER_TEMP_WARN);
1004
1005 /* Calculate the new optimum regulator operating mode based on the new total
1006  * consumer load. All locks held by caller
1007  */
1008 static int drms_uA_update(struct regulator_dev *rdev)
1009 {
1010         struct regulator *sibling;
1011         int current_uA = 0, output_uV, input_uV, err;
1012         unsigned int mode;
1013
1014         /*
1015          * first check to see if we can set modes at all, otherwise just
1016          * tell the consumer everything is OK.
1017          */
1018         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
1019                 rdev_dbg(rdev, "DRMS operation not allowed\n");
1020                 return 0;
1021         }
1022
1023         if (!rdev->desc->ops->get_optimum_mode &&
1024             !rdev->desc->ops->set_load)
1025                 return 0;
1026
1027         if (!rdev->desc->ops->set_mode &&
1028             !rdev->desc->ops->set_load)
1029                 return -EINVAL;
1030
1031         /* calc total requested load */
1032         list_for_each_entry(sibling, &rdev->consumer_list, list) {
1033                 if (sibling->enable_count)
1034                         current_uA += sibling->uA_load;
1035         }
1036
1037         current_uA += rdev->constraints->system_load;
1038
1039         if (rdev->desc->ops->set_load) {
1040                 /* set the optimum mode for our new total regulator load */
1041                 err = rdev->desc->ops->set_load(rdev, current_uA);
1042                 if (err < 0)
1043                         rdev_err(rdev, "failed to set load %d: %pe\n",
1044                                  current_uA, ERR_PTR(err));
1045         } else {
1046                 /*
1047                  * Unfortunately in some cases the constraints->valid_ops has
1048                  * REGULATOR_CHANGE_DRMS but there are no valid modes listed.
1049                  * That's not really legit but we won't consider it a fatal
1050                  * error here. We'll treat it as if REGULATOR_CHANGE_DRMS
1051                  * wasn't set.
1052                  */
1053                 if (!rdev->constraints->valid_modes_mask) {
1054                         rdev_dbg(rdev, "Can change modes; but no valid mode\n");
1055                         return 0;
1056                 }
1057
1058                 /* get output voltage */
1059                 output_uV = regulator_get_voltage_rdev(rdev);
1060
1061                 /*
1062                  * Don't return an error; if regulator driver cares about
1063                  * output_uV then it's up to the driver to validate.
1064                  */
1065                 if (output_uV <= 0)
1066                         rdev_dbg(rdev, "invalid output voltage found\n");
1067
1068                 /* get input voltage */
1069                 input_uV = 0;
1070                 if (rdev->supply)
1071                         input_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
1072                 if (input_uV <= 0)
1073                         input_uV = rdev->constraints->input_uV;
1074
1075                 /*
1076                  * Don't return an error; if regulator driver cares about
1077                  * input_uV then it's up to the driver to validate.
1078                  */
1079                 if (input_uV <= 0)
1080                         rdev_dbg(rdev, "invalid input voltage found\n");
1081
1082                 /* now get the optimum mode for our new total regulator load */
1083                 mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
1084                                                          output_uV, current_uA);
1085
1086                 /* check the new mode is allowed */
1087                 err = regulator_mode_constrain(rdev, &mode);
1088                 if (err < 0) {
1089                         rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
1090                                  current_uA, input_uV, output_uV, ERR_PTR(err));
1091                         return err;
1092                 }
1093
1094                 err = rdev->desc->ops->set_mode(rdev, mode);
1095                 if (err < 0)
1096                         rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
1097                                  mode, ERR_PTR(err));
1098         }
1099
1100         return err;
1101 }
1102
1103 static int __suspend_set_state(struct regulator_dev *rdev,
1104                                const struct regulator_state *rstate)
1105 {
1106         int ret = 0;
1107
1108         if (rstate->enabled == ENABLE_IN_SUSPEND &&
1109                 rdev->desc->ops->set_suspend_enable)
1110                 ret = rdev->desc->ops->set_suspend_enable(rdev);
1111         else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1112                 rdev->desc->ops->set_suspend_disable)
1113                 ret = rdev->desc->ops->set_suspend_disable(rdev);
1114         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1115                 ret = 0;
1116
1117         if (ret < 0) {
1118                 rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
1119                 return ret;
1120         }
1121
1122         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1123                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1124                 if (ret < 0) {
1125                         rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
1126                         return ret;
1127                 }
1128         }
1129
1130         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1131                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1132                 if (ret < 0) {
1133                         rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
1134                         return ret;
1135                 }
1136         }
1137
1138         return ret;
1139 }
1140
1141 static int suspend_set_initial_state(struct regulator_dev *rdev)
1142 {
1143         const struct regulator_state *rstate;
1144
1145         rstate = regulator_get_suspend_state_check(rdev,
1146                         rdev->constraints->initial_state);
1147         if (!rstate)
1148                 return 0;
1149
1150         return __suspend_set_state(rdev, rstate);
1151 }
1152
1153 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
1154 static void print_constraints_debug(struct regulator_dev *rdev)
1155 {
1156         struct regulation_constraints *constraints = rdev->constraints;
1157         char buf[160] = "";
1158         size_t len = sizeof(buf) - 1;
1159         int count = 0;
1160         int ret;
1161
1162         if (constraints->min_uV && constraints->max_uV) {
1163                 if (constraints->min_uV == constraints->max_uV)
1164                         count += scnprintf(buf + count, len - count, "%d mV ",
1165                                            constraints->min_uV / 1000);
1166                 else
1167                         count += scnprintf(buf + count, len - count,
1168                                            "%d <--> %d mV ",
1169                                            constraints->min_uV / 1000,
1170                                            constraints->max_uV / 1000);
1171         }
1172
1173         if (!constraints->min_uV ||
1174             constraints->min_uV != constraints->max_uV) {
1175                 ret = regulator_get_voltage_rdev(rdev);
1176                 if (ret > 0)
1177                         count += scnprintf(buf + count, len - count,
1178                                            "at %d mV ", ret / 1000);
1179         }
1180
1181         if (constraints->uV_offset)
1182                 count += scnprintf(buf + count, len - count, "%dmV offset ",
1183                                    constraints->uV_offset / 1000);
1184
1185         if (constraints->min_uA && constraints->max_uA) {
1186                 if (constraints->min_uA == constraints->max_uA)
1187                         count += scnprintf(buf + count, len - count, "%d mA ",
1188                                            constraints->min_uA / 1000);
1189                 else
1190                         count += scnprintf(buf + count, len - count,
1191                                            "%d <--> %d mA ",
1192                                            constraints->min_uA / 1000,
1193                                            constraints->max_uA / 1000);
1194         }
1195
1196         if (!constraints->min_uA ||
1197             constraints->min_uA != constraints->max_uA) {
1198                 ret = _regulator_get_current_limit(rdev);
1199                 if (ret > 0)
1200                         count += scnprintf(buf + count, len - count,
1201                                            "at %d mA ", ret / 1000);
1202         }
1203
1204         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1205                 count += scnprintf(buf + count, len - count, "fast ");
1206         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1207                 count += scnprintf(buf + count, len - count, "normal ");
1208         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1209                 count += scnprintf(buf + count, len - count, "idle ");
1210         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1211                 count += scnprintf(buf + count, len - count, "standby ");
1212
1213         if (!count)
1214                 count = scnprintf(buf, len, "no parameters");
1215         else
1216                 --count;
1217
1218         count += scnprintf(buf + count, len - count, ", %s",
1219                 _regulator_is_enabled(rdev) ? "enabled" : "disabled");
1220
1221         rdev_dbg(rdev, "%s\n", buf);
1222 }
1223 #else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1224 static inline void print_constraints_debug(struct regulator_dev *rdev) {}
1225 #endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1226
1227 static void print_constraints(struct regulator_dev *rdev)
1228 {
1229         struct regulation_constraints *constraints = rdev->constraints;
1230
1231         print_constraints_debug(rdev);
1232
1233         if ((constraints->min_uV != constraints->max_uV) &&
1234             !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1235                 rdev_warn(rdev,
1236                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1237 }
1238
1239 static int machine_constraints_voltage(struct regulator_dev *rdev,
1240         struct regulation_constraints *constraints)
1241 {
1242         const struct regulator_ops *ops = rdev->desc->ops;
1243         int ret;
1244
1245         /* do we need to apply the constraint voltage */
1246         if (rdev->constraints->apply_uV &&
1247             rdev->constraints->min_uV && rdev->constraints->max_uV) {
1248                 int target_min, target_max;
1249                 int current_uV = regulator_get_voltage_rdev(rdev);
1250
1251                 if (current_uV == -ENOTRECOVERABLE) {
1252                         /* This regulator can't be read and must be initialized */
1253                         rdev_info(rdev, "Setting %d-%duV\n",
1254                                   rdev->constraints->min_uV,
1255                                   rdev->constraints->max_uV);
1256                         _regulator_do_set_voltage(rdev,
1257                                                   rdev->constraints->min_uV,
1258                                                   rdev->constraints->max_uV);
1259                         current_uV = regulator_get_voltage_rdev(rdev);
1260                 }
1261
1262                 if (current_uV < 0) {
1263                         if (current_uV != -EPROBE_DEFER)
1264                                 rdev_err(rdev,
1265                                          "failed to get the current voltage: %pe\n",
1266                                          ERR_PTR(current_uV));
1267                         return current_uV;
1268                 }
1269
1270                 /*
1271                  * If we're below the minimum voltage move up to the
1272                  * minimum voltage, if we're above the maximum voltage
1273                  * then move down to the maximum.
1274                  */
1275                 target_min = current_uV;
1276                 target_max = current_uV;
1277
1278                 if (current_uV < rdev->constraints->min_uV) {
1279                         target_min = rdev->constraints->min_uV;
1280                         target_max = rdev->constraints->min_uV;
1281                 }
1282
1283                 if (current_uV > rdev->constraints->max_uV) {
1284                         target_min = rdev->constraints->max_uV;
1285                         target_max = rdev->constraints->max_uV;
1286                 }
1287
1288                 if (target_min != current_uV || target_max != current_uV) {
1289                         rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1290                                   current_uV, target_min, target_max);
1291                         ret = _regulator_do_set_voltage(
1292                                 rdev, target_min, target_max);
1293                         if (ret < 0) {
1294                                 rdev_err(rdev,
1295                                         "failed to apply %d-%duV constraint: %pe\n",
1296                                         target_min, target_max, ERR_PTR(ret));
1297                                 return ret;
1298                         }
1299                 }
1300         }
1301
1302         /* constrain machine-level voltage specs to fit
1303          * the actual range supported by this regulator.
1304          */
1305         if (ops->list_voltage && rdev->desc->n_voltages) {
1306                 int     count = rdev->desc->n_voltages;
1307                 int     i;
1308                 int     min_uV = INT_MAX;
1309                 int     max_uV = INT_MIN;
1310                 int     cmin = constraints->min_uV;
1311                 int     cmax = constraints->max_uV;
1312
1313                 /* it's safe to autoconfigure fixed-voltage supplies
1314                  * and the constraints are used by list_voltage.
1315                  */
1316                 if (count == 1 && !cmin) {
1317                         cmin = 1;
1318                         cmax = INT_MAX;
1319                         constraints->min_uV = cmin;
1320                         constraints->max_uV = cmax;
1321                 }
1322
1323                 /* voltage constraints are optional */
1324                 if ((cmin == 0) && (cmax == 0))
1325                         return 0;
1326
1327                 /* else require explicit machine-level constraints */
1328                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1329                         rdev_err(rdev, "invalid voltage constraints\n");
1330                         return -EINVAL;
1331                 }
1332
1333                 /* no need to loop voltages if range is continuous */
1334                 if (rdev->desc->continuous_voltage_range)
1335                         return 0;
1336
1337                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1338                 for (i = 0; i < count; i++) {
1339                         int     value;
1340
1341                         value = ops->list_voltage(rdev, i);
1342                         if (value <= 0)
1343                                 continue;
1344
1345                         /* maybe adjust [min_uV..max_uV] */
1346                         if (value >= cmin && value < min_uV)
1347                                 min_uV = value;
1348                         if (value <= cmax && value > max_uV)
1349                                 max_uV = value;
1350                 }
1351
1352                 /* final: [min_uV..max_uV] valid iff constraints valid */
1353                 if (max_uV < min_uV) {
1354                         rdev_err(rdev,
1355                                  "unsupportable voltage constraints %u-%uuV\n",
1356                                  min_uV, max_uV);
1357                         return -EINVAL;
1358                 }
1359
1360                 /* use regulator's subset of machine constraints */
1361                 if (constraints->min_uV < min_uV) {
1362                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1363                                  constraints->min_uV, min_uV);
1364                         constraints->min_uV = min_uV;
1365                 }
1366                 if (constraints->max_uV > max_uV) {
1367                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1368                                  constraints->max_uV, max_uV);
1369                         constraints->max_uV = max_uV;
1370                 }
1371         }
1372
1373         return 0;
1374 }
1375
1376 static int machine_constraints_current(struct regulator_dev *rdev,
1377         struct regulation_constraints *constraints)
1378 {
1379         const struct regulator_ops *ops = rdev->desc->ops;
1380         int ret;
1381
1382         if (!constraints->min_uA && !constraints->max_uA)
1383                 return 0;
1384
1385         if (constraints->min_uA > constraints->max_uA) {
1386                 rdev_err(rdev, "Invalid current constraints\n");
1387                 return -EINVAL;
1388         }
1389
1390         if (!ops->set_current_limit || !ops->get_current_limit) {
1391                 rdev_warn(rdev, "Operation of current configuration missing\n");
1392                 return 0;
1393         }
1394
1395         /* Set regulator current in constraints range */
1396         ret = ops->set_current_limit(rdev, constraints->min_uA,
1397                         constraints->max_uA);
1398         if (ret < 0) {
1399                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1400                 return ret;
1401         }
1402
1403         return 0;
1404 }
1405
1406 static int _regulator_do_enable(struct regulator_dev *rdev);
1407
1408 static int notif_set_limit(struct regulator_dev *rdev,
1409                            int (*set)(struct regulator_dev *, int, int, bool),
1410                            int limit, int severity)
1411 {
1412         bool enable;
1413
1414         if (limit == REGULATOR_NOTIF_LIMIT_DISABLE) {
1415                 enable = false;
1416                 limit = 0;
1417         } else {
1418                 enable = true;
1419         }
1420
1421         if (limit == REGULATOR_NOTIF_LIMIT_ENABLE)
1422                 limit = 0;
1423
1424         return set(rdev, limit, severity, enable);
1425 }
1426
1427 static int handle_notify_limits(struct regulator_dev *rdev,
1428                         int (*set)(struct regulator_dev *, int, int, bool),
1429                         struct notification_limit *limits)
1430 {
1431         int ret = 0;
1432
1433         if (!set)
1434                 return -EOPNOTSUPP;
1435
1436         if (limits->prot)
1437                 ret = notif_set_limit(rdev, set, limits->prot,
1438                                       REGULATOR_SEVERITY_PROT);
1439         if (ret)
1440                 return ret;
1441
1442         if (limits->err)
1443                 ret = notif_set_limit(rdev, set, limits->err,
1444                                       REGULATOR_SEVERITY_ERR);
1445         if (ret)
1446                 return ret;
1447
1448         if (limits->warn)
1449                 ret = notif_set_limit(rdev, set, limits->warn,
1450                                       REGULATOR_SEVERITY_WARN);
1451
1452         return ret;
1453 }
1454 /**
1455  * set_machine_constraints - sets regulator constraints
1456  * @rdev: regulator source
1457  *
1458  * Allows platform initialisation code to define and constrain
1459  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1460  * Constraints *must* be set by platform code in order for some
1461  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1462  * set_mode.
1463  */
1464 static int set_machine_constraints(struct regulator_dev *rdev)
1465 {
1466         int ret = 0;
1467         const struct regulator_ops *ops = rdev->desc->ops;
1468
1469         ret = machine_constraints_voltage(rdev, rdev->constraints);
1470         if (ret != 0)
1471                 return ret;
1472
1473         ret = machine_constraints_current(rdev, rdev->constraints);
1474         if (ret != 0)
1475                 return ret;
1476
1477         if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1478                 ret = ops->set_input_current_limit(rdev,
1479                                                    rdev->constraints->ilim_uA);
1480                 if (ret < 0) {
1481                         rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
1482                         return ret;
1483                 }
1484         }
1485
1486         /* do we need to setup our suspend state */
1487         if (rdev->constraints->initial_state) {
1488                 ret = suspend_set_initial_state(rdev);
1489                 if (ret < 0) {
1490                         rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
1491                         return ret;
1492                 }
1493         }
1494
1495         if (rdev->constraints->initial_mode) {
1496                 if (!ops->set_mode) {
1497                         rdev_err(rdev, "no set_mode operation\n");
1498                         return -EINVAL;
1499                 }
1500
1501                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1502                 if (ret < 0) {
1503                         rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
1504                         return ret;
1505                 }
1506         } else if (rdev->constraints->system_load) {
1507                 /*
1508                  * We'll only apply the initial system load if an
1509                  * initial mode wasn't specified.
1510                  */
1511                 drms_uA_update(rdev);
1512         }
1513
1514         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1515                 && ops->set_ramp_delay) {
1516                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1517                 if (ret < 0) {
1518                         rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
1519                         return ret;
1520                 }
1521         }
1522
1523         if (rdev->constraints->pull_down && ops->set_pull_down) {
1524                 ret = ops->set_pull_down(rdev);
1525                 if (ret < 0) {
1526                         rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
1527                         return ret;
1528                 }
1529         }
1530
1531         if (rdev->constraints->soft_start && ops->set_soft_start) {
1532                 ret = ops->set_soft_start(rdev);
1533                 if (ret < 0) {
1534                         rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
1535                         return ret;
1536                 }
1537         }
1538
1539         /*
1540          * Existing logic does not warn if over_current_protection is given as
1541          * a constraint but driver does not support that. I think we should
1542          * warn about this type of issues as it is possible someone changes
1543          * PMIC on board to another type - and the another PMIC's driver does
1544          * not support setting protection. Board composer may happily believe
1545          * the DT limits are respected - especially if the new PMIC HW also
1546          * supports protection but the driver does not. I won't change the logic
1547          * without hearing more experienced opinion on this though.
1548          *
1549          * If warning is seen as a good idea then we can merge handling the
1550          * over-curret protection and detection and get rid of this special
1551          * handling.
1552          */
1553         if (rdev->constraints->over_current_protection
1554                 && ops->set_over_current_protection) {
1555                 int lim = rdev->constraints->over_curr_limits.prot;
1556
1557                 ret = ops->set_over_current_protection(rdev, lim,
1558                                                        REGULATOR_SEVERITY_PROT,
1559                                                        true);
1560                 if (ret < 0) {
1561                         rdev_err(rdev, "failed to set over current protection: %pe\n",
1562                                  ERR_PTR(ret));
1563                         return ret;
1564                 }
1565         }
1566
1567         if (rdev->constraints->over_current_detection)
1568                 ret = handle_notify_limits(rdev,
1569                                            ops->set_over_current_protection,
1570                                            &rdev->constraints->over_curr_limits);
1571         if (ret) {
1572                 if (ret != -EOPNOTSUPP) {
1573                         rdev_err(rdev, "failed to set over current limits: %pe\n",
1574                                  ERR_PTR(ret));
1575                         return ret;
1576                 }
1577                 rdev_warn(rdev,
1578                           "IC does not support requested over-current limits\n");
1579         }
1580
1581         if (rdev->constraints->over_voltage_detection)
1582                 ret = handle_notify_limits(rdev,
1583                                            ops->set_over_voltage_protection,
1584                                            &rdev->constraints->over_voltage_limits);
1585         if (ret) {
1586                 if (ret != -EOPNOTSUPP) {
1587                         rdev_err(rdev, "failed to set over voltage limits %pe\n",
1588                                  ERR_PTR(ret));
1589                         return ret;
1590                 }
1591                 rdev_warn(rdev,
1592                           "IC does not support requested over voltage limits\n");
1593         }
1594
1595         if (rdev->constraints->under_voltage_detection)
1596                 ret = handle_notify_limits(rdev,
1597                                            ops->set_under_voltage_protection,
1598                                            &rdev->constraints->under_voltage_limits);
1599         if (ret) {
1600                 if (ret != -EOPNOTSUPP) {
1601                         rdev_err(rdev, "failed to set under voltage limits %pe\n",
1602                                  ERR_PTR(ret));
1603                         return ret;
1604                 }
1605                 rdev_warn(rdev,
1606                           "IC does not support requested under voltage limits\n");
1607         }
1608
1609         if (rdev->constraints->over_temp_detection)
1610                 ret = handle_notify_limits(rdev,
1611                                            ops->set_thermal_protection,
1612                                            &rdev->constraints->temp_limits);
1613         if (ret) {
1614                 if (ret != -EOPNOTSUPP) {
1615                         rdev_err(rdev, "failed to set temperature limits %pe\n",
1616                                  ERR_PTR(ret));
1617                         return ret;
1618                 }
1619                 rdev_warn(rdev,
1620                           "IC does not support requested temperature limits\n");
1621         }
1622
1623         if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1624                 bool ad_state = (rdev->constraints->active_discharge ==
1625                               REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1626
1627                 ret = ops->set_active_discharge(rdev, ad_state);
1628                 if (ret < 0) {
1629                         rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
1630                         return ret;
1631                 }
1632         }
1633
1634         /*
1635          * If there is no mechanism for controlling the regulator then
1636          * flag it as always_on so we don't end up duplicating checks
1637          * for this so much.  Note that we could control the state of
1638          * a supply to control the output on a regulator that has no
1639          * direct control.
1640          */
1641         if (!rdev->ena_pin && !ops->enable) {
1642                 if (rdev->supply_name && !rdev->supply)
1643                         return -EPROBE_DEFER;
1644
1645                 if (rdev->supply)
1646                         rdev->constraints->always_on =
1647                                 rdev->supply->rdev->constraints->always_on;
1648                 else
1649                         rdev->constraints->always_on = true;
1650         }
1651
1652         /* If the constraints say the regulator should be on at this point
1653          * and we have control then make sure it is enabled.
1654          */
1655         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1656                 /* If we want to enable this regulator, make sure that we know
1657                  * the supplying regulator.
1658                  */
1659                 if (rdev->supply_name && !rdev->supply)
1660                         return -EPROBE_DEFER;
1661
1662                 /* If supplying regulator has already been enabled,
1663                  * it's not intended to have use_count increment
1664                  * when rdev is only boot-on.
1665                  */
1666                 if (rdev->supply &&
1667                     (rdev->constraints->always_on ||
1668                      !regulator_is_enabled(rdev->supply))) {
1669                         ret = regulator_enable(rdev->supply);
1670                         if (ret < 0) {
1671                                 _regulator_put(rdev->supply);
1672                                 rdev->supply = NULL;
1673                                 return ret;
1674                         }
1675                 }
1676
1677                 ret = _regulator_do_enable(rdev);
1678                 if (ret < 0 && ret != -EINVAL) {
1679                         rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
1680                         return ret;
1681                 }
1682
1683                 if (rdev->constraints->always_on)
1684                         rdev->use_count++;
1685         } else if (rdev->desc->off_on_delay) {
1686                 rdev->last_off = ktime_get();
1687         }
1688
1689         print_constraints(rdev);
1690         return 0;
1691 }
1692
1693 /**
1694  * set_supply - set regulator supply regulator
1695  * @rdev: regulator (locked)
1696  * @supply_rdev: supply regulator (locked))
1697  *
1698  * Called by platform initialisation code to set the supply regulator for this
1699  * regulator. This ensures that a regulators supply will also be enabled by the
1700  * core if it's child is enabled.
1701  */
1702 static int set_supply(struct regulator_dev *rdev,
1703                       struct regulator_dev *supply_rdev)
1704 {
1705         int err;
1706
1707         rdev_dbg(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1708
1709         if (!try_module_get(supply_rdev->owner))
1710                 return -ENODEV;
1711
1712         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1713         if (rdev->supply == NULL) {
1714                 module_put(supply_rdev->owner);
1715                 err = -ENOMEM;
1716                 return err;
1717         }
1718         supply_rdev->open_count++;
1719
1720         return 0;
1721 }
1722
1723 /**
1724  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1725  * @rdev:         regulator source
1726  * @consumer_dev_name: dev_name() string for device supply applies to
1727  * @supply:       symbolic name for supply
1728  *
1729  * Allows platform initialisation code to map physical regulator
1730  * sources to symbolic names for supplies for use by devices.  Devices
1731  * should use these symbolic names to request regulators, avoiding the
1732  * need to provide board-specific regulator names as platform data.
1733  */
1734 static int set_consumer_device_supply(struct regulator_dev *rdev,
1735                                       const char *consumer_dev_name,
1736                                       const char *supply)
1737 {
1738         struct regulator_map *node, *new_node;
1739         int has_dev;
1740
1741         if (supply == NULL)
1742                 return -EINVAL;
1743
1744         if (consumer_dev_name != NULL)
1745                 has_dev = 1;
1746         else
1747                 has_dev = 0;
1748
1749         new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1750         if (new_node == NULL)
1751                 return -ENOMEM;
1752
1753         new_node->regulator = rdev;
1754         new_node->supply = supply;
1755
1756         if (has_dev) {
1757                 new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1758                 if (new_node->dev_name == NULL) {
1759                         kfree(new_node);
1760                         return -ENOMEM;
1761                 }
1762         }
1763
1764         mutex_lock(&regulator_list_mutex);
1765         list_for_each_entry(node, &regulator_map_list, list) {
1766                 if (node->dev_name && consumer_dev_name) {
1767                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1768                                 continue;
1769                 } else if (node->dev_name || consumer_dev_name) {
1770                         continue;
1771                 }
1772
1773                 if (strcmp(node->supply, supply) != 0)
1774                         continue;
1775
1776                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1777                          consumer_dev_name,
1778                          dev_name(&node->regulator->dev),
1779                          node->regulator->desc->name,
1780                          supply,
1781                          dev_name(&rdev->dev), rdev_get_name(rdev));
1782                 goto fail;
1783         }
1784
1785         list_add(&new_node->list, &regulator_map_list);
1786         mutex_unlock(&regulator_list_mutex);
1787
1788         return 0;
1789
1790 fail:
1791         mutex_unlock(&regulator_list_mutex);
1792         kfree(new_node->dev_name);
1793         kfree(new_node);
1794         return -EBUSY;
1795 }
1796
1797 static void unset_regulator_supplies(struct regulator_dev *rdev)
1798 {
1799         struct regulator_map *node, *n;
1800
1801         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1802                 if (rdev == node->regulator) {
1803                         list_del(&node->list);
1804                         kfree(node->dev_name);
1805                         kfree(node);
1806                 }
1807         }
1808 }
1809
1810 #ifdef CONFIG_DEBUG_FS
1811 static ssize_t constraint_flags_read_file(struct file *file,
1812                                           char __user *user_buf,
1813                                           size_t count, loff_t *ppos)
1814 {
1815         const struct regulator *regulator = file->private_data;
1816         const struct regulation_constraints *c = regulator->rdev->constraints;
1817         char *buf;
1818         ssize_t ret;
1819
1820         if (!c)
1821                 return 0;
1822
1823         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1824         if (!buf)
1825                 return -ENOMEM;
1826
1827         ret = snprintf(buf, PAGE_SIZE,
1828                         "always_on: %u\n"
1829                         "boot_on: %u\n"
1830                         "apply_uV: %u\n"
1831                         "ramp_disable: %u\n"
1832                         "soft_start: %u\n"
1833                         "pull_down: %u\n"
1834                         "over_current_protection: %u\n",
1835                         c->always_on,
1836                         c->boot_on,
1837                         c->apply_uV,
1838                         c->ramp_disable,
1839                         c->soft_start,
1840                         c->pull_down,
1841                         c->over_current_protection);
1842
1843         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1844         kfree(buf);
1845
1846         return ret;
1847 }
1848
1849 #endif
1850
1851 static const struct file_operations constraint_flags_fops = {
1852 #ifdef CONFIG_DEBUG_FS
1853         .open = simple_open,
1854         .read = constraint_flags_read_file,
1855         .llseek = default_llseek,
1856 #endif
1857 };
1858
1859 #define REG_STR_SIZE    64
1860
1861 static struct regulator *create_regulator(struct regulator_dev *rdev,
1862                                           struct device *dev,
1863                                           const char *supply_name)
1864 {
1865         struct regulator *regulator;
1866         int err = 0;
1867
1868         lockdep_assert_held_once(&rdev->mutex.base);
1869
1870         if (dev) {
1871                 char buf[REG_STR_SIZE];
1872                 int size;
1873
1874                 size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1875                                 dev->kobj.name, supply_name);
1876                 if (size >= REG_STR_SIZE)
1877                         return NULL;
1878
1879                 supply_name = kstrdup(buf, GFP_KERNEL);
1880                 if (supply_name == NULL)
1881                         return NULL;
1882         } else {
1883                 supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1884                 if (supply_name == NULL)
1885                         return NULL;
1886         }
1887
1888         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1889         if (regulator == NULL) {
1890                 kfree_const(supply_name);
1891                 return NULL;
1892         }
1893
1894         regulator->rdev = rdev;
1895         regulator->supply_name = supply_name;
1896
1897         list_add(&regulator->list, &rdev->consumer_list);
1898
1899         if (dev) {
1900                 regulator->dev = dev;
1901
1902                 /* Add a link to the device sysfs entry */
1903                 err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1904                                                supply_name);
1905                 if (err) {
1906                         rdev_dbg(rdev, "could not add device link %s: %pe\n",
1907                                   dev->kobj.name, ERR_PTR(err));
1908                         /* non-fatal */
1909                 }
1910         }
1911
1912         if (err != -EEXIST)
1913                 regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
1914         if (!regulator->debugfs) {
1915                 rdev_dbg(rdev, "Failed to create debugfs directory\n");
1916         } else {
1917                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1918                                    &regulator->uA_load);
1919                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1920                                    &regulator->voltage[PM_SUSPEND_ON].min_uV);
1921                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1922                                    &regulator->voltage[PM_SUSPEND_ON].max_uV);
1923                 debugfs_create_file("constraint_flags", 0444,
1924                                     regulator->debugfs, regulator,
1925                                     &constraint_flags_fops);
1926         }
1927
1928         /*
1929          * Check now if the regulator is an always on regulator - if
1930          * it is then we don't need to do nearly so much work for
1931          * enable/disable calls.
1932          */
1933         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1934             _regulator_is_enabled(rdev))
1935                 regulator->always_on = true;
1936
1937         return regulator;
1938 }
1939
1940 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1941 {
1942         if (rdev->constraints && rdev->constraints->enable_time)
1943                 return rdev->constraints->enable_time;
1944         if (rdev->desc->ops->enable_time)
1945                 return rdev->desc->ops->enable_time(rdev);
1946         return rdev->desc->enable_time;
1947 }
1948
1949 static struct regulator_supply_alias *regulator_find_supply_alias(
1950                 struct device *dev, const char *supply)
1951 {
1952         struct regulator_supply_alias *map;
1953
1954         list_for_each_entry(map, &regulator_supply_alias_list, list)
1955                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1956                         return map;
1957
1958         return NULL;
1959 }
1960
1961 static void regulator_supply_alias(struct device **dev, const char **supply)
1962 {
1963         struct regulator_supply_alias *map;
1964
1965         map = regulator_find_supply_alias(*dev, *supply);
1966         if (map) {
1967                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1968                                 *supply, map->alias_supply,
1969                                 dev_name(map->alias_dev));
1970                 *dev = map->alias_dev;
1971                 *supply = map->alias_supply;
1972         }
1973 }
1974
1975 static int regulator_match(struct device *dev, const void *data)
1976 {
1977         struct regulator_dev *r = dev_to_rdev(dev);
1978
1979         return strcmp(rdev_get_name(r), data) == 0;
1980 }
1981
1982 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1983 {
1984         struct device *dev;
1985
1986         dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1987
1988         return dev ? dev_to_rdev(dev) : NULL;
1989 }
1990
1991 /**
1992  * regulator_dev_lookup - lookup a regulator device.
1993  * @dev: device for regulator "consumer".
1994  * @supply: Supply name or regulator ID.
1995  *
1996  * If successful, returns a struct regulator_dev that corresponds to the name
1997  * @supply and with the embedded struct device refcount incremented by one.
1998  * The refcount must be dropped by calling put_device().
1999  * On failure one of the following ERR-PTR-encoded values is returned:
2000  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
2001  * in the future.
2002  */
2003 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
2004                                                   const char *supply)
2005 {
2006         struct regulator_dev *r = NULL;
2007         struct device_node *node;
2008         struct regulator_map *map;
2009         const char *devname = NULL;
2010
2011         regulator_supply_alias(&dev, &supply);
2012
2013         /* first do a dt based lookup */
2014         if (dev && dev->of_node) {
2015                 node = of_get_regulator(dev, supply);
2016                 if (node) {
2017                         r = of_find_regulator_by_node(node);
2018                         of_node_put(node);
2019                         if (r)
2020                                 return r;
2021
2022                         /*
2023                          * We have a node, but there is no device.
2024                          * assume it has not registered yet.
2025                          */
2026                         return ERR_PTR(-EPROBE_DEFER);
2027                 }
2028         }
2029
2030         /* if not found, try doing it non-dt way */
2031         if (dev)
2032                 devname = dev_name(dev);
2033
2034         mutex_lock(&regulator_list_mutex);
2035         list_for_each_entry(map, &regulator_map_list, list) {
2036                 /* If the mapping has a device set up it must match */
2037                 if (map->dev_name &&
2038                     (!devname || strcmp(map->dev_name, devname)))
2039                         continue;
2040
2041                 if (strcmp(map->supply, supply) == 0 &&
2042                     get_device(&map->regulator->dev)) {
2043                         r = map->regulator;
2044                         break;
2045                 }
2046         }
2047         mutex_unlock(&regulator_list_mutex);
2048
2049         if (r)
2050                 return r;
2051
2052         r = regulator_lookup_by_name(supply);
2053         if (r)
2054                 return r;
2055
2056         return ERR_PTR(-ENODEV);
2057 }
2058
2059 static int regulator_resolve_supply(struct regulator_dev *rdev)
2060 {
2061         struct regulator_dev *r;
2062         struct device *dev = rdev->dev.parent;
2063         struct ww_acquire_ctx ww_ctx;
2064         int ret = 0;
2065
2066         /* No supply to resolve? */
2067         if (!rdev->supply_name)
2068                 return 0;
2069
2070         /* Supply already resolved? (fast-path without locking contention) */
2071         if (rdev->supply)
2072                 return 0;
2073
2074         r = regulator_dev_lookup(dev, rdev->supply_name);
2075         if (IS_ERR(r)) {
2076                 ret = PTR_ERR(r);
2077
2078                 /* Did the lookup explicitly defer for us? */
2079                 if (ret == -EPROBE_DEFER)
2080                         goto out;
2081
2082                 if (have_full_constraints()) {
2083                         r = dummy_regulator_rdev;
2084                         get_device(&r->dev);
2085                 } else {
2086                         dev_err(dev, "Failed to resolve %s-supply for %s\n",
2087                                 rdev->supply_name, rdev->desc->name);
2088                         ret = -EPROBE_DEFER;
2089                         goto out;
2090                 }
2091         }
2092
2093         if (r == rdev) {
2094                 dev_err(dev, "Supply for %s (%s) resolved to itself\n",
2095                         rdev->desc->name, rdev->supply_name);
2096                 if (!have_full_constraints()) {
2097                         ret = -EINVAL;
2098                         goto out;
2099                 }
2100                 r = dummy_regulator_rdev;
2101                 get_device(&r->dev);
2102         }
2103
2104         /*
2105          * If the supply's parent device is not the same as the
2106          * regulator's parent device, then ensure the parent device
2107          * is bound before we resolve the supply, in case the parent
2108          * device get probe deferred and unregisters the supply.
2109          */
2110         if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
2111                 if (!device_is_bound(r->dev.parent)) {
2112                         put_device(&r->dev);
2113                         ret = -EPROBE_DEFER;
2114                         goto out;
2115                 }
2116         }
2117
2118         /* Recursively resolve the supply of the supply */
2119         ret = regulator_resolve_supply(r);
2120         if (ret < 0) {
2121                 put_device(&r->dev);
2122                 goto out;
2123         }
2124
2125         /*
2126          * Recheck rdev->supply with rdev->mutex lock held to avoid a race
2127          * between rdev->supply null check and setting rdev->supply in
2128          * set_supply() from concurrent tasks.
2129          */
2130         regulator_lock_two(rdev, r, &ww_ctx);
2131
2132         /* Supply just resolved by a concurrent task? */
2133         if (rdev->supply) {
2134                 regulator_unlock_two(rdev, r, &ww_ctx);
2135                 put_device(&r->dev);
2136                 goto out;
2137         }
2138
2139         ret = set_supply(rdev, r);
2140         if (ret < 0) {
2141                 regulator_unlock_two(rdev, r, &ww_ctx);
2142                 put_device(&r->dev);
2143                 goto out;
2144         }
2145
2146         regulator_unlock_two(rdev, r, &ww_ctx);
2147
2148         /*
2149          * In set_machine_constraints() we may have turned this regulator on
2150          * but we couldn't propagate to the supply if it hadn't been resolved
2151          * yet.  Do it now.
2152          */
2153         if (rdev->use_count) {
2154                 ret = regulator_enable(rdev->supply);
2155                 if (ret < 0) {
2156                         _regulator_put(rdev->supply);
2157                         rdev->supply = NULL;
2158                         goto out;
2159                 }
2160         }
2161
2162 out:
2163         return ret;
2164 }
2165
2166 /* Internal regulator request function */
2167 struct regulator *_regulator_get(struct device *dev, const char *id,
2168                                  enum regulator_get_type get_type)
2169 {
2170         struct regulator_dev *rdev;
2171         struct regulator *regulator;
2172         struct device_link *link;
2173         int ret;
2174
2175         if (get_type >= MAX_GET_TYPE) {
2176                 dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
2177                 return ERR_PTR(-EINVAL);
2178         }
2179
2180         if (id == NULL) {
2181                 pr_err("get() with no identifier\n");
2182                 return ERR_PTR(-EINVAL);
2183         }
2184
2185         rdev = regulator_dev_lookup(dev, id);
2186         if (IS_ERR(rdev)) {
2187                 ret = PTR_ERR(rdev);
2188
2189                 /*
2190                  * If regulator_dev_lookup() fails with error other
2191                  * than -ENODEV our job here is done, we simply return it.
2192                  */
2193                 if (ret != -ENODEV)
2194                         return ERR_PTR(ret);
2195
2196                 if (!have_full_constraints()) {
2197                         dev_warn(dev,
2198                                  "incomplete constraints, dummy supplies not allowed\n");
2199                         return ERR_PTR(-ENODEV);
2200                 }
2201
2202                 switch (get_type) {
2203                 case NORMAL_GET:
2204                         /*
2205                          * Assume that a regulator is physically present and
2206                          * enabled, even if it isn't hooked up, and just
2207                          * provide a dummy.
2208                          */
2209                         dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
2210                         rdev = dummy_regulator_rdev;
2211                         get_device(&rdev->dev);
2212                         break;
2213
2214                 case EXCLUSIVE_GET:
2215                         dev_warn(dev,
2216                                  "dummy supplies not allowed for exclusive requests\n");
2217                         fallthrough;
2218
2219                 default:
2220                         return ERR_PTR(-ENODEV);
2221                 }
2222         }
2223
2224         if (rdev->exclusive) {
2225                 regulator = ERR_PTR(-EPERM);
2226                 put_device(&rdev->dev);
2227                 return regulator;
2228         }
2229
2230         if (get_type == EXCLUSIVE_GET && rdev->open_count) {
2231                 regulator = ERR_PTR(-EBUSY);
2232                 put_device(&rdev->dev);
2233                 return regulator;
2234         }
2235
2236         mutex_lock(&regulator_list_mutex);
2237         ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
2238         mutex_unlock(&regulator_list_mutex);
2239
2240         if (ret != 0) {
2241                 regulator = ERR_PTR(-EPROBE_DEFER);
2242                 put_device(&rdev->dev);
2243                 return regulator;
2244         }
2245
2246         ret = regulator_resolve_supply(rdev);
2247         if (ret < 0) {
2248                 regulator = ERR_PTR(ret);
2249                 put_device(&rdev->dev);
2250                 return regulator;
2251         }
2252
2253         if (!try_module_get(rdev->owner)) {
2254                 regulator = ERR_PTR(-EPROBE_DEFER);
2255                 put_device(&rdev->dev);
2256                 return regulator;
2257         }
2258
2259         regulator_lock(rdev);
2260         regulator = create_regulator(rdev, dev, id);
2261         regulator_unlock(rdev);
2262         if (regulator == NULL) {
2263                 regulator = ERR_PTR(-ENOMEM);
2264                 module_put(rdev->owner);
2265                 put_device(&rdev->dev);
2266                 return regulator;
2267         }
2268
2269         rdev->open_count++;
2270         if (get_type == EXCLUSIVE_GET) {
2271                 rdev->exclusive = 1;
2272
2273                 ret = _regulator_is_enabled(rdev);
2274                 if (ret > 0) {
2275                         rdev->use_count = 1;
2276                         regulator->enable_count = 1;
2277                 } else {
2278                         rdev->use_count = 0;
2279                         regulator->enable_count = 0;
2280                 }
2281         }
2282
2283         link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
2284         if (!IS_ERR_OR_NULL(link))
2285                 regulator->device_link = true;
2286
2287         return regulator;
2288 }
2289
2290 /**
2291  * regulator_get - lookup and obtain a reference to a regulator.
2292  * @dev: device for regulator "consumer"
2293  * @id: Supply name or regulator ID.
2294  *
2295  * Returns a struct regulator corresponding to the regulator producer,
2296  * or IS_ERR() condition containing errno.
2297  *
2298  * Use of supply names configured via set_consumer_device_supply() is
2299  * strongly encouraged.  It is recommended that the supply name used
2300  * should match the name used for the supply and/or the relevant
2301  * device pins in the datasheet.
2302  */
2303 struct regulator *regulator_get(struct device *dev, const char *id)
2304 {
2305         return _regulator_get(dev, id, NORMAL_GET);
2306 }
2307 EXPORT_SYMBOL_GPL(regulator_get);
2308
2309 /**
2310  * regulator_get_exclusive - obtain exclusive access to a regulator.
2311  * @dev: device for regulator "consumer"
2312  * @id: Supply name or regulator ID.
2313  *
2314  * Returns a struct regulator corresponding to the regulator producer,
2315  * or IS_ERR() condition containing errno.  Other consumers will be
2316  * unable to obtain this regulator while this reference is held and the
2317  * use count for the regulator will be initialised to reflect the current
2318  * state of the regulator.
2319  *
2320  * This is intended for use by consumers which cannot tolerate shared
2321  * use of the regulator such as those which need to force the
2322  * regulator off for correct operation of the hardware they are
2323  * controlling.
2324  *
2325  * Use of supply names configured via set_consumer_device_supply() is
2326  * strongly encouraged.  It is recommended that the supply name used
2327  * should match the name used for the supply and/or the relevant
2328  * device pins in the datasheet.
2329  */
2330 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
2331 {
2332         return _regulator_get(dev, id, EXCLUSIVE_GET);
2333 }
2334 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2335
2336 /**
2337  * regulator_get_optional - obtain optional access to a regulator.
2338  * @dev: device for regulator "consumer"
2339  * @id: Supply name or regulator ID.
2340  *
2341  * Returns a struct regulator corresponding to the regulator producer,
2342  * or IS_ERR() condition containing errno.
2343  *
2344  * This is intended for use by consumers for devices which can have
2345  * some supplies unconnected in normal use, such as some MMC devices.
2346  * It can allow the regulator core to provide stub supplies for other
2347  * supplies requested using normal regulator_get() calls without
2348  * disrupting the operation of drivers that can handle absent
2349  * supplies.
2350  *
2351  * Use of supply names configured via set_consumer_device_supply() is
2352  * strongly encouraged.  It is recommended that the supply name used
2353  * should match the name used for the supply and/or the relevant
2354  * device pins in the datasheet.
2355  */
2356 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2357 {
2358         return _regulator_get(dev, id, OPTIONAL_GET);
2359 }
2360 EXPORT_SYMBOL_GPL(regulator_get_optional);
2361
2362 static void destroy_regulator(struct regulator *regulator)
2363 {
2364         struct regulator_dev *rdev = regulator->rdev;
2365
2366         debugfs_remove_recursive(regulator->debugfs);
2367
2368         if (regulator->dev) {
2369                 if (regulator->device_link)
2370                         device_link_remove(regulator->dev, &rdev->dev);
2371
2372                 /* remove any sysfs entries */
2373                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2374         }
2375
2376         regulator_lock(rdev);
2377         list_del(&regulator->list);
2378
2379         rdev->open_count--;
2380         rdev->exclusive = 0;
2381         regulator_unlock(rdev);
2382
2383         kfree_const(regulator->supply_name);
2384         kfree(regulator);
2385 }
2386
2387 /* regulator_list_mutex lock held by regulator_put() */
2388 static void _regulator_put(struct regulator *regulator)
2389 {
2390         struct regulator_dev *rdev;
2391
2392         if (IS_ERR_OR_NULL(regulator))
2393                 return;
2394
2395         lockdep_assert_held_once(&regulator_list_mutex);
2396
2397         /* Docs say you must disable before calling regulator_put() */
2398         WARN_ON(regulator->enable_count);
2399
2400         rdev = regulator->rdev;
2401
2402         destroy_regulator(regulator);
2403
2404         module_put(rdev->owner);
2405         put_device(&rdev->dev);
2406 }
2407
2408 /**
2409  * regulator_put - "free" the regulator source
2410  * @regulator: regulator source
2411  *
2412  * Note: drivers must ensure that all regulator_enable calls made on this
2413  * regulator source are balanced by regulator_disable calls prior to calling
2414  * this function.
2415  */
2416 void regulator_put(struct regulator *regulator)
2417 {
2418         mutex_lock(&regulator_list_mutex);
2419         _regulator_put(regulator);
2420         mutex_unlock(&regulator_list_mutex);
2421 }
2422 EXPORT_SYMBOL_GPL(regulator_put);
2423
2424 /**
2425  * regulator_register_supply_alias - Provide device alias for supply lookup
2426  *
2427  * @dev: device that will be given as the regulator "consumer"
2428  * @id: Supply name or regulator ID
2429  * @alias_dev: device that should be used to lookup the supply
2430  * @alias_id: Supply name or regulator ID that should be used to lookup the
2431  * supply
2432  *
2433  * All lookups for id on dev will instead be conducted for alias_id on
2434  * alias_dev.
2435  */
2436 int regulator_register_supply_alias(struct device *dev, const char *id,
2437                                     struct device *alias_dev,
2438                                     const char *alias_id)
2439 {
2440         struct regulator_supply_alias *map;
2441
2442         map = regulator_find_supply_alias(dev, id);
2443         if (map)
2444                 return -EEXIST;
2445
2446         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2447         if (!map)
2448                 return -ENOMEM;
2449
2450         map->src_dev = dev;
2451         map->src_supply = id;
2452         map->alias_dev = alias_dev;
2453         map->alias_supply = alias_id;
2454
2455         list_add(&map->list, &regulator_supply_alias_list);
2456
2457         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2458                 id, dev_name(dev), alias_id, dev_name(alias_dev));
2459
2460         return 0;
2461 }
2462 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2463
2464 /**
2465  * regulator_unregister_supply_alias - Remove device alias
2466  *
2467  * @dev: device that will be given as the regulator "consumer"
2468  * @id: Supply name or regulator ID
2469  *
2470  * Remove a lookup alias if one exists for id on dev.
2471  */
2472 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2473 {
2474         struct regulator_supply_alias *map;
2475
2476         map = regulator_find_supply_alias(dev, id);
2477         if (map) {
2478                 list_del(&map->list);
2479                 kfree(map);
2480         }
2481 }
2482 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2483
2484 /**
2485  * regulator_bulk_register_supply_alias - register multiple aliases
2486  *
2487  * @dev: device that will be given as the regulator "consumer"
2488  * @id: List of supply names or regulator IDs
2489  * @alias_dev: device that should be used to lookup the supply
2490  * @alias_id: List of supply names or regulator IDs that should be used to
2491  * lookup the supply
2492  * @num_id: Number of aliases to register
2493  *
2494  * @return 0 on success, an errno on failure.
2495  *
2496  * This helper function allows drivers to register several supply
2497  * aliases in one operation.  If any of the aliases cannot be
2498  * registered any aliases that were registered will be removed
2499  * before returning to the caller.
2500  */
2501 int regulator_bulk_register_supply_alias(struct device *dev,
2502                                          const char *const *id,
2503                                          struct device *alias_dev,
2504                                          const char *const *alias_id,
2505                                          int num_id)
2506 {
2507         int i;
2508         int ret;
2509
2510         for (i = 0; i < num_id; ++i) {
2511                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2512                                                       alias_id[i]);
2513                 if (ret < 0)
2514                         goto err;
2515         }
2516
2517         return 0;
2518
2519 err:
2520         dev_err(dev,
2521                 "Failed to create supply alias %s,%s -> %s,%s\n",
2522                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2523
2524         while (--i >= 0)
2525                 regulator_unregister_supply_alias(dev, id[i]);
2526
2527         return ret;
2528 }
2529 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2530
2531 /**
2532  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2533  *
2534  * @dev: device that will be given as the regulator "consumer"
2535  * @id: List of supply names or regulator IDs
2536  * @num_id: Number of aliases to unregister
2537  *
2538  * This helper function allows drivers to unregister several supply
2539  * aliases in one operation.
2540  */
2541 void regulator_bulk_unregister_supply_alias(struct device *dev,
2542                                             const char *const *id,
2543                                             int num_id)
2544 {
2545         int i;
2546
2547         for (i = 0; i < num_id; ++i)
2548                 regulator_unregister_supply_alias(dev, id[i]);
2549 }
2550 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2551
2552
2553 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2554 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2555                                 const struct regulator_config *config)
2556 {
2557         struct regulator_enable_gpio *pin, *new_pin;
2558         struct gpio_desc *gpiod;
2559
2560         gpiod = config->ena_gpiod;
2561         new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
2562
2563         mutex_lock(&regulator_list_mutex);
2564
2565         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2566                 if (pin->gpiod == gpiod) {
2567                         rdev_dbg(rdev, "GPIO is already used\n");
2568                         goto update_ena_gpio_to_rdev;
2569                 }
2570         }
2571
2572         if (new_pin == NULL) {
2573                 mutex_unlock(&regulator_list_mutex);
2574                 return -ENOMEM;
2575         }
2576
2577         pin = new_pin;
2578         new_pin = NULL;
2579
2580         pin->gpiod = gpiod;
2581         list_add(&pin->list, &regulator_ena_gpio_list);
2582
2583 update_ena_gpio_to_rdev:
2584         pin->request_count++;
2585         rdev->ena_pin = pin;
2586
2587         mutex_unlock(&regulator_list_mutex);
2588         kfree(new_pin);
2589
2590         return 0;
2591 }
2592
2593 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2594 {
2595         struct regulator_enable_gpio *pin, *n;
2596
2597         if (!rdev->ena_pin)
2598                 return;
2599
2600         /* Free the GPIO only in case of no use */
2601         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2602                 if (pin != rdev->ena_pin)
2603                         continue;
2604
2605                 if (--pin->request_count)
2606                         break;
2607
2608                 gpiod_put(pin->gpiod);
2609                 list_del(&pin->list);
2610                 kfree(pin);
2611                 break;
2612         }
2613
2614         rdev->ena_pin = NULL;
2615 }
2616
2617 /**
2618  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2619  * @rdev: regulator_dev structure
2620  * @enable: enable GPIO at initial use?
2621  *
2622  * GPIO is enabled in case of initial use. (enable_count is 0)
2623  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2624  */
2625 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2626 {
2627         struct regulator_enable_gpio *pin = rdev->ena_pin;
2628
2629         if (!pin)
2630                 return -EINVAL;
2631
2632         if (enable) {
2633                 /* Enable GPIO at initial use */
2634                 if (pin->enable_count == 0)
2635                         gpiod_set_value_cansleep(pin->gpiod, 1);
2636
2637                 pin->enable_count++;
2638         } else {
2639                 if (pin->enable_count > 1) {
2640                         pin->enable_count--;
2641                         return 0;
2642                 }
2643
2644                 /* Disable GPIO if not used */
2645                 if (pin->enable_count <= 1) {
2646                         gpiod_set_value_cansleep(pin->gpiod, 0);
2647                         pin->enable_count = 0;
2648                 }
2649         }
2650
2651         return 0;
2652 }
2653
2654 /**
2655  * _regulator_delay_helper - a delay helper function
2656  * @delay: time to delay in microseconds
2657  *
2658  * Delay for the requested amount of time as per the guidelines in:
2659  *
2660  *     Documentation/timers/timers-howto.rst
2661  *
2662  * The assumption here is that these regulator operations will never used in
2663  * atomic context and therefore sleeping functions can be used.
2664  */
2665 static void _regulator_delay_helper(unsigned int delay)
2666 {
2667         unsigned int ms = delay / 1000;
2668         unsigned int us = delay % 1000;
2669
2670         if (ms > 0) {
2671                 /*
2672                  * For small enough values, handle super-millisecond
2673                  * delays in the usleep_range() call below.
2674                  */
2675                 if (ms < 20)
2676                         us += ms * 1000;
2677                 else
2678                         msleep(ms);
2679         }
2680
2681         /*
2682          * Give the scheduler some room to coalesce with any other
2683          * wakeup sources. For delays shorter than 10 us, don't even
2684          * bother setting up high-resolution timers and just busy-
2685          * loop.
2686          */
2687         if (us >= 10)
2688                 usleep_range(us, us + 100);
2689         else
2690                 udelay(us);
2691 }
2692
2693 /**
2694  * _regulator_check_status_enabled
2695  *
2696  * A helper function to check if the regulator status can be interpreted
2697  * as 'regulator is enabled'.
2698  * @rdev: the regulator device to check
2699  *
2700  * Return:
2701  * * 1                  - if status shows regulator is in enabled state
2702  * * 0                  - if not enabled state
2703  * * Error Value        - as received from ops->get_status()
2704  */
2705 static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
2706 {
2707         int ret = rdev->desc->ops->get_status(rdev);
2708
2709         if (ret < 0) {
2710                 rdev_info(rdev, "get_status returned error: %d\n", ret);
2711                 return ret;
2712         }
2713
2714         switch (ret) {
2715         case REGULATOR_STATUS_OFF:
2716         case REGULATOR_STATUS_ERROR:
2717         case REGULATOR_STATUS_UNDEFINED:
2718                 return 0;
2719         default:
2720                 return 1;
2721         }
2722 }
2723
2724 static int _regulator_do_enable(struct regulator_dev *rdev)
2725 {
2726         int ret, delay;
2727
2728         /* Query before enabling in case configuration dependent.  */
2729         ret = _regulator_get_enable_time(rdev);
2730         if (ret >= 0) {
2731                 delay = ret;
2732         } else {
2733                 rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
2734                 delay = 0;
2735         }
2736
2737         trace_regulator_enable(rdev_get_name(rdev));
2738
2739         if (rdev->desc->off_on_delay) {
2740                 /* if needed, keep a distance of off_on_delay from last time
2741                  * this regulator was disabled.
2742                  */
2743                 ktime_t end = ktime_add_us(rdev->last_off, rdev->desc->off_on_delay);
2744                 s64 remaining = ktime_us_delta(end, ktime_get_boottime());
2745
2746                 if (remaining > 0)
2747                         _regulator_delay_helper(remaining);
2748         }
2749
2750         if (rdev->ena_pin) {
2751                 if (!rdev->ena_gpio_state) {
2752                         ret = regulator_ena_gpio_ctrl(rdev, true);
2753                         if (ret < 0)
2754                                 return ret;
2755                         rdev->ena_gpio_state = 1;
2756                 }
2757         } else if (rdev->desc->ops->enable) {
2758                 ret = rdev->desc->ops->enable(rdev);
2759                 if (ret < 0)
2760                         return ret;
2761         } else {
2762                 return -EINVAL;
2763         }
2764
2765         /* Allow the regulator to ramp; it would be useful to extend
2766          * this for bulk operations so that the regulators can ramp
2767          * together.
2768          */
2769         trace_regulator_enable_delay(rdev_get_name(rdev));
2770
2771         /* If poll_enabled_time is set, poll upto the delay calculated
2772          * above, delaying poll_enabled_time uS to check if the regulator
2773          * actually got enabled.
2774          * If the regulator isn't enabled after our delay helper has expired,
2775          * return -ETIMEDOUT.
2776          */
2777         if (rdev->desc->poll_enabled_time) {
2778                 int time_remaining = delay;
2779
2780                 while (time_remaining > 0) {
2781                         _regulator_delay_helper(rdev->desc->poll_enabled_time);
2782
2783                         if (rdev->desc->ops->get_status) {
2784                                 ret = _regulator_check_status_enabled(rdev);
2785                                 if (ret < 0)
2786                                         return ret;
2787                                 else if (ret)
2788                                         break;
2789                         } else if (rdev->desc->ops->is_enabled(rdev))
2790                                 break;
2791
2792                         time_remaining -= rdev->desc->poll_enabled_time;
2793                 }
2794
2795                 if (time_remaining <= 0) {
2796                         rdev_err(rdev, "Enabled check timed out\n");
2797                         return -ETIMEDOUT;
2798                 }
2799         } else {
2800                 _regulator_delay_helper(delay);
2801         }
2802
2803         trace_regulator_enable_complete(rdev_get_name(rdev));
2804
2805         return 0;
2806 }
2807
2808 /**
2809  * _regulator_handle_consumer_enable - handle that a consumer enabled
2810  * @regulator: regulator source
2811  *
2812  * Some things on a regulator consumer (like the contribution towards total
2813  * load on the regulator) only have an effect when the consumer wants the
2814  * regulator enabled.  Explained in example with two consumers of the same
2815  * regulator:
2816  *   consumer A: set_load(100);       => total load = 0
2817  *   consumer A: regulator_enable();  => total load = 100
2818  *   consumer B: set_load(1000);      => total load = 100
2819  *   consumer B: regulator_enable();  => total load = 1100
2820  *   consumer A: regulator_disable(); => total_load = 1000
2821  *
2822  * This function (together with _regulator_handle_consumer_disable) is
2823  * responsible for keeping track of the refcount for a given regulator consumer
2824  * and applying / unapplying these things.
2825  *
2826  * Returns 0 upon no error; -error upon error.
2827  */
2828 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2829 {
2830         int ret;
2831         struct regulator_dev *rdev = regulator->rdev;
2832
2833         lockdep_assert_held_once(&rdev->mutex.base);
2834
2835         regulator->enable_count++;
2836         if (regulator->uA_load && regulator->enable_count == 1) {
2837                 ret = drms_uA_update(rdev);
2838                 if (ret)
2839                         regulator->enable_count--;
2840                 return ret;
2841         }
2842
2843         return 0;
2844 }
2845
2846 /**
2847  * _regulator_handle_consumer_disable - handle that a consumer disabled
2848  * @regulator: regulator source
2849  *
2850  * The opposite of _regulator_handle_consumer_enable().
2851  *
2852  * Returns 0 upon no error; -error upon error.
2853  */
2854 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2855 {
2856         struct regulator_dev *rdev = regulator->rdev;
2857
2858         lockdep_assert_held_once(&rdev->mutex.base);
2859
2860         if (!regulator->enable_count) {
2861                 rdev_err(rdev, "Underflow of regulator enable count\n");
2862                 return -EINVAL;
2863         }
2864
2865         regulator->enable_count--;
2866         if (regulator->uA_load && regulator->enable_count == 0)
2867                 return drms_uA_update(rdev);
2868
2869         return 0;
2870 }
2871
2872 /* locks held by regulator_enable() */
2873 static int _regulator_enable(struct regulator *regulator)
2874 {
2875         struct regulator_dev *rdev = regulator->rdev;
2876         int ret;
2877
2878         lockdep_assert_held_once(&rdev->mutex.base);
2879
2880         if (rdev->use_count == 0 && rdev->supply) {
2881                 ret = _regulator_enable(rdev->supply);
2882                 if (ret < 0)
2883                         return ret;
2884         }
2885
2886         /* balance only if there are regulators coupled */
2887         if (rdev->coupling_desc.n_coupled > 1) {
2888                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2889                 if (ret < 0)
2890                         goto err_disable_supply;
2891         }
2892
2893         ret = _regulator_handle_consumer_enable(regulator);
2894         if (ret < 0)
2895                 goto err_disable_supply;
2896
2897         if (rdev->use_count == 0) {
2898                 /*
2899                  * The regulator may already be enabled if it's not switchable
2900                  * or was left on
2901                  */
2902                 ret = _regulator_is_enabled(rdev);
2903                 if (ret == -EINVAL || ret == 0) {
2904                         if (!regulator_ops_is_valid(rdev,
2905                                         REGULATOR_CHANGE_STATUS)) {
2906                                 ret = -EPERM;
2907                                 goto err_consumer_disable;
2908                         }
2909
2910                         ret = _regulator_do_enable(rdev);
2911                         if (ret < 0)
2912                                 goto err_consumer_disable;
2913
2914                         _notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2915                                              NULL);
2916                 } else if (ret < 0) {
2917                         rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
2918                         goto err_consumer_disable;
2919                 }
2920                 /* Fallthrough on positive return values - already enabled */
2921         }
2922
2923         rdev->use_count++;
2924
2925         return 0;
2926
2927 err_consumer_disable:
2928         _regulator_handle_consumer_disable(regulator);
2929
2930 err_disable_supply:
2931         if (rdev->use_count == 0 && rdev->supply)
2932                 _regulator_disable(rdev->supply);
2933
2934         return ret;
2935 }
2936
2937 /**
2938  * regulator_enable - enable regulator output
2939  * @regulator: regulator source
2940  *
2941  * Request that the regulator be enabled with the regulator output at
2942  * the predefined voltage or current value.  Calls to regulator_enable()
2943  * must be balanced with calls to regulator_disable().
2944  *
2945  * NOTE: the output value can be set by other drivers, boot loader or may be
2946  * hardwired in the regulator.
2947  */
2948 int regulator_enable(struct regulator *regulator)
2949 {
2950         struct regulator_dev *rdev = regulator->rdev;
2951         struct ww_acquire_ctx ww_ctx;
2952         int ret;
2953
2954         regulator_lock_dependent(rdev, &ww_ctx);
2955         ret = _regulator_enable(regulator);
2956         regulator_unlock_dependent(rdev, &ww_ctx);
2957
2958         return ret;
2959 }
2960 EXPORT_SYMBOL_GPL(regulator_enable);
2961
2962 static int _regulator_do_disable(struct regulator_dev *rdev)
2963 {
2964         int ret;
2965
2966         trace_regulator_disable(rdev_get_name(rdev));
2967
2968         if (rdev->ena_pin) {
2969                 if (rdev->ena_gpio_state) {
2970                         ret = regulator_ena_gpio_ctrl(rdev, false);
2971                         if (ret < 0)
2972                                 return ret;
2973                         rdev->ena_gpio_state = 0;
2974                 }
2975
2976         } else if (rdev->desc->ops->disable) {
2977                 ret = rdev->desc->ops->disable(rdev);
2978                 if (ret != 0)
2979                         return ret;
2980         }
2981
2982         if (rdev->desc->off_on_delay)
2983                 rdev->last_off = ktime_get_boottime();
2984
2985         trace_regulator_disable_complete(rdev_get_name(rdev));
2986
2987         return 0;
2988 }
2989
2990 /* locks held by regulator_disable() */
2991 static int _regulator_disable(struct regulator *regulator)
2992 {
2993         struct regulator_dev *rdev = regulator->rdev;
2994         int ret = 0;
2995
2996         lockdep_assert_held_once(&rdev->mutex.base);
2997
2998         if (WARN(rdev->use_count <= 0,
2999                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
3000                 return -EIO;
3001
3002         /* are we the last user and permitted to disable ? */
3003         if (rdev->use_count == 1 &&
3004             (rdev->constraints && !rdev->constraints->always_on)) {
3005
3006                 /* we are last user */
3007                 if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
3008                         ret = _notifier_call_chain(rdev,
3009                                                    REGULATOR_EVENT_PRE_DISABLE,
3010                                                    NULL);
3011                         if (ret & NOTIFY_STOP_MASK)
3012                                 return -EINVAL;
3013
3014                         ret = _regulator_do_disable(rdev);
3015                         if (ret < 0) {
3016                                 rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
3017                                 _notifier_call_chain(rdev,
3018                                                 REGULATOR_EVENT_ABORT_DISABLE,
3019                                                 NULL);
3020                                 return ret;
3021                         }
3022                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
3023                                         NULL);
3024                 }
3025
3026                 rdev->use_count = 0;
3027         } else if (rdev->use_count > 1) {
3028                 rdev->use_count--;
3029         }
3030
3031         if (ret == 0)
3032                 ret = _regulator_handle_consumer_disable(regulator);
3033
3034         if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
3035                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3036
3037         if (ret == 0 && rdev->use_count == 0 && rdev->supply)
3038                 ret = _regulator_disable(rdev->supply);
3039
3040         return ret;
3041 }
3042
3043 /**
3044  * regulator_disable - disable regulator output
3045  * @regulator: regulator source
3046  *
3047  * Disable the regulator output voltage or current.  Calls to
3048  * regulator_enable() must be balanced with calls to
3049  * regulator_disable().
3050  *
3051  * NOTE: this will only disable the regulator output if no other consumer
3052  * devices have it enabled, the regulator device supports disabling and
3053  * machine constraints permit this operation.
3054  */
3055 int regulator_disable(struct regulator *regulator)
3056 {
3057         struct regulator_dev *rdev = regulator->rdev;
3058         struct ww_acquire_ctx ww_ctx;
3059         int ret;
3060
3061         regulator_lock_dependent(rdev, &ww_ctx);
3062         ret = _regulator_disable(regulator);
3063         regulator_unlock_dependent(rdev, &ww_ctx);
3064
3065         return ret;
3066 }
3067 EXPORT_SYMBOL_GPL(regulator_disable);
3068
3069 /* locks held by regulator_force_disable() */
3070 static int _regulator_force_disable(struct regulator_dev *rdev)
3071 {
3072         int ret = 0;
3073
3074         lockdep_assert_held_once(&rdev->mutex.base);
3075
3076         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3077                         REGULATOR_EVENT_PRE_DISABLE, NULL);
3078         if (ret & NOTIFY_STOP_MASK)
3079                 return -EINVAL;
3080
3081         ret = _regulator_do_disable(rdev);
3082         if (ret < 0) {
3083                 rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
3084                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3085                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
3086                 return ret;
3087         }
3088
3089         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3090                         REGULATOR_EVENT_DISABLE, NULL);
3091
3092         return 0;
3093 }
3094
3095 /**
3096  * regulator_force_disable - force disable regulator output
3097  * @regulator: regulator source
3098  *
3099  * Forcibly disable the regulator output voltage or current.
3100  * NOTE: this *will* disable the regulator output even if other consumer
3101  * devices have it enabled. This should be used for situations when device
3102  * damage will likely occur if the regulator is not disabled (e.g. over temp).
3103  */
3104 int regulator_force_disable(struct regulator *regulator)
3105 {
3106         struct regulator_dev *rdev = regulator->rdev;
3107         struct ww_acquire_ctx ww_ctx;
3108         int ret;
3109
3110         regulator_lock_dependent(rdev, &ww_ctx);
3111
3112         ret = _regulator_force_disable(regulator->rdev);
3113
3114         if (rdev->coupling_desc.n_coupled > 1)
3115                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3116
3117         if (regulator->uA_load) {
3118                 regulator->uA_load = 0;
3119                 ret = drms_uA_update(rdev);
3120         }
3121
3122         if (rdev->use_count != 0 && rdev->supply)
3123                 _regulator_disable(rdev->supply);
3124
3125         regulator_unlock_dependent(rdev, &ww_ctx);
3126
3127         return ret;
3128 }
3129 EXPORT_SYMBOL_GPL(regulator_force_disable);
3130
3131 static void regulator_disable_work(struct work_struct *work)
3132 {
3133         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
3134                                                   disable_work.work);
3135         struct ww_acquire_ctx ww_ctx;
3136         int count, i, ret;
3137         struct regulator *regulator;
3138         int total_count = 0;
3139
3140         regulator_lock_dependent(rdev, &ww_ctx);
3141
3142         /*
3143          * Workqueue functions queue the new work instance while the previous
3144          * work instance is being processed. Cancel the queued work instance
3145          * as the work instance under processing does the job of the queued
3146          * work instance.
3147          */
3148         cancel_delayed_work(&rdev->disable_work);
3149
3150         list_for_each_entry(regulator, &rdev->consumer_list, list) {
3151                 count = regulator->deferred_disables;
3152
3153                 if (!count)
3154                         continue;
3155
3156                 total_count += count;
3157                 regulator->deferred_disables = 0;
3158
3159                 for (i = 0; i < count; i++) {
3160                         ret = _regulator_disable(regulator);
3161                         if (ret != 0)
3162                                 rdev_err(rdev, "Deferred disable failed: %pe\n",
3163                                          ERR_PTR(ret));
3164                 }
3165         }
3166         WARN_ON(!total_count);
3167
3168         if (rdev->coupling_desc.n_coupled > 1)
3169                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3170
3171         regulator_unlock_dependent(rdev, &ww_ctx);
3172 }
3173
3174 /**
3175  * regulator_disable_deferred - disable regulator output with delay
3176  * @regulator: regulator source
3177  * @ms: milliseconds until the regulator is disabled
3178  *
3179  * Execute regulator_disable() on the regulator after a delay.  This
3180  * is intended for use with devices that require some time to quiesce.
3181  *
3182  * NOTE: this will only disable the regulator output if no other consumer
3183  * devices have it enabled, the regulator device supports disabling and
3184  * machine constraints permit this operation.
3185  */
3186 int regulator_disable_deferred(struct regulator *regulator, int ms)
3187 {
3188         struct regulator_dev *rdev = regulator->rdev;
3189
3190         if (!ms)
3191                 return regulator_disable(regulator);
3192
3193         regulator_lock(rdev);
3194         regulator->deferred_disables++;
3195         mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
3196                          msecs_to_jiffies(ms));
3197         regulator_unlock(rdev);
3198
3199         return 0;
3200 }
3201 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
3202
3203 static int _regulator_is_enabled(struct regulator_dev *rdev)
3204 {
3205         /* A GPIO control always takes precedence */
3206         if (rdev->ena_pin)
3207                 return rdev->ena_gpio_state;
3208
3209         /* If we don't know then assume that the regulator is always on */
3210         if (!rdev->desc->ops->is_enabled)
3211                 return 1;
3212
3213         return rdev->desc->ops->is_enabled(rdev);
3214 }
3215
3216 static int _regulator_list_voltage(struct regulator_dev *rdev,
3217                                    unsigned selector, int lock)
3218 {
3219         const struct regulator_ops *ops = rdev->desc->ops;
3220         int ret;
3221
3222         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
3223                 return rdev->desc->fixed_uV;
3224
3225         if (ops->list_voltage) {
3226                 if (selector >= rdev->desc->n_voltages)
3227                         return -EINVAL;
3228                 if (selector < rdev->desc->linear_min_sel)
3229                         return 0;
3230                 if (lock)
3231                         regulator_lock(rdev);
3232                 ret = ops->list_voltage(rdev, selector);
3233                 if (lock)
3234                         regulator_unlock(rdev);
3235         } else if (rdev->is_switch && rdev->supply) {
3236                 ret = _regulator_list_voltage(rdev->supply->rdev,
3237                                               selector, lock);
3238         } else {
3239                 return -EINVAL;
3240         }
3241
3242         if (ret > 0) {
3243                 if (ret < rdev->constraints->min_uV)
3244                         ret = 0;
3245                 else if (ret > rdev->constraints->max_uV)
3246                         ret = 0;
3247         }
3248
3249         return ret;
3250 }
3251
3252 /**
3253  * regulator_is_enabled - is the regulator output enabled
3254  * @regulator: regulator source
3255  *
3256  * Returns positive if the regulator driver backing the source/client
3257  * has requested that the device be enabled, zero if it hasn't, else a
3258  * negative errno code.
3259  *
3260  * Note that the device backing this regulator handle can have multiple
3261  * users, so it might be enabled even if regulator_enable() was never
3262  * called for this particular source.
3263  */
3264 int regulator_is_enabled(struct regulator *regulator)
3265 {
3266         int ret;
3267
3268         if (regulator->always_on)
3269                 return 1;
3270
3271         regulator_lock(regulator->rdev);
3272         ret = _regulator_is_enabled(regulator->rdev);
3273         regulator_unlock(regulator->rdev);
3274
3275         return ret;
3276 }
3277 EXPORT_SYMBOL_GPL(regulator_is_enabled);
3278
3279 /**
3280  * regulator_count_voltages - count regulator_list_voltage() selectors
3281  * @regulator: regulator source
3282  *
3283  * Returns number of selectors, or negative errno.  Selectors are
3284  * numbered starting at zero, and typically correspond to bitfields
3285  * in hardware registers.
3286  */
3287 int regulator_count_voltages(struct regulator *regulator)
3288 {
3289         struct regulator_dev    *rdev = regulator->rdev;
3290
3291         if (rdev->desc->n_voltages)
3292                 return rdev->desc->n_voltages;
3293
3294         if (!rdev->is_switch || !rdev->supply)
3295                 return -EINVAL;
3296
3297         return regulator_count_voltages(rdev->supply);
3298 }
3299 EXPORT_SYMBOL_GPL(regulator_count_voltages);
3300
3301 /**
3302  * regulator_list_voltage - enumerate supported voltages
3303  * @regulator: regulator source
3304  * @selector: identify voltage to list
3305  * Context: can sleep
3306  *
3307  * Returns a voltage that can be passed to @regulator_set_voltage(),
3308  * zero if this selector code can't be used on this system, or a
3309  * negative errno.
3310  */
3311 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
3312 {
3313         return _regulator_list_voltage(regulator->rdev, selector, 1);
3314 }
3315 EXPORT_SYMBOL_GPL(regulator_list_voltage);
3316
3317 /**
3318  * regulator_get_regmap - get the regulator's register map
3319  * @regulator: regulator source
3320  *
3321  * Returns the register map for the given regulator, or an ERR_PTR value
3322  * if the regulator doesn't use regmap.
3323  */
3324 struct regmap *regulator_get_regmap(struct regulator *regulator)
3325 {
3326         struct regmap *map = regulator->rdev->regmap;
3327
3328         return map ? map : ERR_PTR(-EOPNOTSUPP);
3329 }
3330
3331 /**
3332  * regulator_get_hardware_vsel_register - get the HW voltage selector register
3333  * @regulator: regulator source
3334  * @vsel_reg: voltage selector register, output parameter
3335  * @vsel_mask: mask for voltage selector bitfield, output parameter
3336  *
3337  * Returns the hardware register offset and bitmask used for setting the
3338  * regulator voltage. This might be useful when configuring voltage-scaling
3339  * hardware or firmware that can make I2C requests behind the kernel's back,
3340  * for example.
3341  *
3342  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
3343  * and 0 is returned, otherwise a negative errno is returned.
3344  */
3345 int regulator_get_hardware_vsel_register(struct regulator *regulator,
3346                                          unsigned *vsel_reg,
3347                                          unsigned *vsel_mask)
3348 {
3349         struct regulator_dev *rdev = regulator->rdev;
3350         const struct regulator_ops *ops = rdev->desc->ops;
3351
3352         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3353                 return -EOPNOTSUPP;
3354
3355         *vsel_reg = rdev->desc->vsel_reg;
3356         *vsel_mask = rdev->desc->vsel_mask;
3357
3358         return 0;
3359 }
3360 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
3361
3362 /**
3363  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
3364  * @regulator: regulator source
3365  * @selector: identify voltage to list
3366  *
3367  * Converts the selector to a hardware-specific voltage selector that can be
3368  * directly written to the regulator registers. The address of the voltage
3369  * register can be determined by calling @regulator_get_hardware_vsel_register.
3370  *
3371  * On error a negative errno is returned.
3372  */
3373 int regulator_list_hardware_vsel(struct regulator *regulator,
3374                                  unsigned selector)
3375 {
3376         struct regulator_dev *rdev = regulator->rdev;
3377         const struct regulator_ops *ops = rdev->desc->ops;
3378
3379         if (selector >= rdev->desc->n_voltages)
3380                 return -EINVAL;
3381         if (selector < rdev->desc->linear_min_sel)
3382                 return 0;
3383         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3384                 return -EOPNOTSUPP;
3385
3386         return selector;
3387 }
3388 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
3389
3390 /**
3391  * regulator_get_linear_step - return the voltage step size between VSEL values
3392  * @regulator: regulator source
3393  *
3394  * Returns the voltage step size between VSEL values for linear
3395  * regulators, or return 0 if the regulator isn't a linear regulator.
3396  */
3397 unsigned int regulator_get_linear_step(struct regulator *regulator)
3398 {
3399         struct regulator_dev *rdev = regulator->rdev;
3400
3401         return rdev->desc->uV_step;
3402 }
3403 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3404
3405 /**
3406  * regulator_is_supported_voltage - check if a voltage range can be supported
3407  *
3408  * @regulator: Regulator to check.
3409  * @min_uV: Minimum required voltage in uV.
3410  * @max_uV: Maximum required voltage in uV.
3411  *
3412  * Returns a boolean.
3413  */
3414 int regulator_is_supported_voltage(struct regulator *regulator,
3415                                    int min_uV, int max_uV)
3416 {
3417         struct regulator_dev *rdev = regulator->rdev;
3418         int i, voltages, ret;
3419
3420         /* If we can't change voltage check the current voltage */
3421         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3422                 ret = regulator_get_voltage(regulator);
3423                 if (ret >= 0)
3424                         return min_uV <= ret && ret <= max_uV;
3425                 else
3426                         return ret;
3427         }
3428
3429         /* Any voltage within constrains range is fine? */
3430         if (rdev->desc->continuous_voltage_range)
3431                 return min_uV >= rdev->constraints->min_uV &&
3432                                 max_uV <= rdev->constraints->max_uV;
3433
3434         ret = regulator_count_voltages(regulator);
3435         if (ret < 0)
3436                 return 0;
3437         voltages = ret;
3438
3439         for (i = 0; i < voltages; i++) {
3440                 ret = regulator_list_voltage(regulator, i);
3441
3442                 if (ret >= min_uV && ret <= max_uV)
3443                         return 1;
3444         }
3445
3446         return 0;
3447 }
3448 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3449
3450 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3451                                  int max_uV)
3452 {
3453         const struct regulator_desc *desc = rdev->desc;
3454
3455         if (desc->ops->map_voltage)
3456                 return desc->ops->map_voltage(rdev, min_uV, max_uV);
3457
3458         if (desc->ops->list_voltage == regulator_list_voltage_linear)
3459                 return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3460
3461         if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3462                 return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3463
3464         if (desc->ops->list_voltage ==
3465                 regulator_list_voltage_pickable_linear_range)
3466                 return regulator_map_voltage_pickable_linear_range(rdev,
3467                                                         min_uV, max_uV);
3468
3469         return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3470 }
3471
3472 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3473                                        int min_uV, int max_uV,
3474                                        unsigned *selector)
3475 {
3476         struct pre_voltage_change_data data;
3477         int ret;
3478
3479         data.old_uV = regulator_get_voltage_rdev(rdev);
3480         data.min_uV = min_uV;
3481         data.max_uV = max_uV;
3482         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3483                                    &data);
3484         if (ret & NOTIFY_STOP_MASK)
3485                 return -EINVAL;
3486
3487         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3488         if (ret >= 0)
3489                 return ret;
3490
3491         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3492                              (void *)data.old_uV);
3493
3494         return ret;
3495 }
3496
3497 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3498                                            int uV, unsigned selector)
3499 {
3500         struct pre_voltage_change_data data;
3501         int ret;
3502
3503         data.old_uV = regulator_get_voltage_rdev(rdev);
3504         data.min_uV = uV;
3505         data.max_uV = uV;
3506         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3507                                    &data);
3508         if (ret & NOTIFY_STOP_MASK)
3509                 return -EINVAL;
3510
3511         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3512         if (ret >= 0)
3513                 return ret;
3514
3515         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3516                              (void *)data.old_uV);
3517
3518         return ret;
3519 }
3520
3521 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3522                                            int uV, int new_selector)
3523 {
3524         const struct regulator_ops *ops = rdev->desc->ops;
3525         int diff, old_sel, curr_sel, ret;
3526
3527         /* Stepping is only needed if the regulator is enabled. */
3528         if (!_regulator_is_enabled(rdev))
3529                 goto final_set;
3530
3531         if (!ops->get_voltage_sel)
3532                 return -EINVAL;
3533
3534         old_sel = ops->get_voltage_sel(rdev);
3535         if (old_sel < 0)
3536                 return old_sel;
3537
3538         diff = new_selector - old_sel;
3539         if (diff == 0)
3540                 return 0; /* No change needed. */
3541
3542         if (diff > 0) {
3543                 /* Stepping up. */
3544                 for (curr_sel = old_sel + rdev->desc->vsel_step;
3545                      curr_sel < new_selector;
3546                      curr_sel += rdev->desc->vsel_step) {
3547                         /*
3548                          * Call the callback directly instead of using
3549                          * _regulator_call_set_voltage_sel() as we don't
3550                          * want to notify anyone yet. Same in the branch
3551                          * below.
3552                          */
3553                         ret = ops->set_voltage_sel(rdev, curr_sel);
3554                         if (ret)
3555                                 goto try_revert;
3556                 }
3557         } else {
3558                 /* Stepping down. */
3559                 for (curr_sel = old_sel - rdev->desc->vsel_step;
3560                      curr_sel > new_selector;
3561                      curr_sel -= rdev->desc->vsel_step) {
3562                         ret = ops->set_voltage_sel(rdev, curr_sel);
3563                         if (ret)
3564                                 goto try_revert;
3565                 }
3566         }
3567
3568 final_set:
3569         /* The final selector will trigger the notifiers. */
3570         return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3571
3572 try_revert:
3573         /*
3574          * At least try to return to the previous voltage if setting a new
3575          * one failed.
3576          */
3577         (void)ops->set_voltage_sel(rdev, old_sel);
3578         return ret;
3579 }
3580
3581 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3582                                        int old_uV, int new_uV)
3583 {
3584         unsigned int ramp_delay = 0;
3585
3586         if (rdev->constraints->ramp_delay)
3587                 ramp_delay = rdev->constraints->ramp_delay;
3588         else if (rdev->desc->ramp_delay)
3589                 ramp_delay = rdev->desc->ramp_delay;
3590         else if (rdev->constraints->settling_time)
3591                 return rdev->constraints->settling_time;
3592         else if (rdev->constraints->settling_time_up &&
3593                  (new_uV > old_uV))
3594                 return rdev->constraints->settling_time_up;
3595         else if (rdev->constraints->settling_time_down &&
3596                  (new_uV < old_uV))
3597                 return rdev->constraints->settling_time_down;
3598
3599         if (ramp_delay == 0)
3600                 return 0;
3601
3602         return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3603 }
3604
3605 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3606                                      int min_uV, int max_uV)
3607 {
3608         int ret;
3609         int delay = 0;
3610         int best_val = 0;
3611         unsigned int selector;
3612         int old_selector = -1;
3613         const struct regulator_ops *ops = rdev->desc->ops;
3614         int old_uV = regulator_get_voltage_rdev(rdev);
3615
3616         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3617
3618         min_uV += rdev->constraints->uV_offset;
3619         max_uV += rdev->constraints->uV_offset;
3620
3621         /*
3622          * If we can't obtain the old selector there is not enough
3623          * info to call set_voltage_time_sel().
3624          */
3625         if (_regulator_is_enabled(rdev) &&
3626             ops->set_voltage_time_sel && ops->get_voltage_sel) {
3627                 old_selector = ops->get_voltage_sel(rdev);
3628                 if (old_selector < 0)
3629                         return old_selector;
3630         }
3631
3632         if (ops->set_voltage) {
3633                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3634                                                   &selector);
3635
3636                 if (ret >= 0) {
3637                         if (ops->list_voltage)
3638                                 best_val = ops->list_voltage(rdev,
3639                                                              selector);
3640                         else
3641                                 best_val = regulator_get_voltage_rdev(rdev);
3642                 }
3643
3644         } else if (ops->set_voltage_sel) {
3645                 ret = regulator_map_voltage(rdev, min_uV, max_uV);
3646                 if (ret >= 0) {
3647                         best_val = ops->list_voltage(rdev, ret);
3648                         if (min_uV <= best_val && max_uV >= best_val) {
3649                                 selector = ret;
3650                                 if (old_selector == selector)
3651                                         ret = 0;
3652                                 else if (rdev->desc->vsel_step)
3653                                         ret = _regulator_set_voltage_sel_step(
3654                                                 rdev, best_val, selector);
3655                                 else
3656                                         ret = _regulator_call_set_voltage_sel(
3657                                                 rdev, best_val, selector);
3658                         } else {
3659                                 ret = -EINVAL;
3660                         }
3661                 }
3662         } else {
3663                 ret = -EINVAL;
3664         }
3665
3666         if (ret)
3667                 goto out;
3668
3669         if (ops->set_voltage_time_sel) {
3670                 /*
3671                  * Call set_voltage_time_sel if successfully obtained
3672                  * old_selector
3673                  */
3674                 if (old_selector >= 0 && old_selector != selector)
3675                         delay = ops->set_voltage_time_sel(rdev, old_selector,
3676                                                           selector);
3677         } else {
3678                 if (old_uV != best_val) {
3679                         if (ops->set_voltage_time)
3680                                 delay = ops->set_voltage_time(rdev, old_uV,
3681                                                               best_val);
3682                         else
3683                                 delay = _regulator_set_voltage_time(rdev,
3684                                                                     old_uV,
3685                                                                     best_val);
3686                 }
3687         }
3688
3689         if (delay < 0) {
3690                 rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
3691                 delay = 0;
3692         }
3693
3694         /* Insert any necessary delays */
3695         _regulator_delay_helper(delay);
3696
3697         if (best_val >= 0) {
3698                 unsigned long data = best_val;
3699
3700                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3701                                      (void *)data);
3702         }
3703
3704 out:
3705         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3706
3707         return ret;
3708 }
3709
3710 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3711                                   int min_uV, int max_uV, suspend_state_t state)
3712 {
3713         struct regulator_state *rstate;
3714         int uV, sel;
3715
3716         rstate = regulator_get_suspend_state(rdev, state);
3717         if (rstate == NULL)
3718                 return -EINVAL;
3719
3720         if (min_uV < rstate->min_uV)
3721                 min_uV = rstate->min_uV;
3722         if (max_uV > rstate->max_uV)
3723                 max_uV = rstate->max_uV;
3724
3725         sel = regulator_map_voltage(rdev, min_uV, max_uV);
3726         if (sel < 0)
3727                 return sel;
3728
3729         uV = rdev->desc->ops->list_voltage(rdev, sel);
3730         if (uV >= min_uV && uV <= max_uV)
3731                 rstate->uV = uV;
3732
3733         return 0;
3734 }
3735
3736 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3737                                           int min_uV, int max_uV,
3738                                           suspend_state_t state)
3739 {
3740         struct regulator_dev *rdev = regulator->rdev;
3741         struct regulator_voltage *voltage = &regulator->voltage[state];
3742         int ret = 0;
3743         int old_min_uV, old_max_uV;
3744         int current_uV;
3745
3746         /* If we're setting the same range as last time the change
3747          * should be a noop (some cpufreq implementations use the same
3748          * voltage for multiple frequencies, for example).
3749          */
3750         if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3751                 goto out;
3752
3753         /* If we're trying to set a range that overlaps the current voltage,
3754          * return successfully even though the regulator does not support
3755          * changing the voltage.
3756          */
3757         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3758                 current_uV = regulator_get_voltage_rdev(rdev);
3759                 if (min_uV <= current_uV && current_uV <= max_uV) {
3760                         voltage->min_uV = min_uV;
3761                         voltage->max_uV = max_uV;
3762                         goto out;
3763                 }
3764         }
3765
3766         /* sanity check */
3767         if (!rdev->desc->ops->set_voltage &&
3768             !rdev->desc->ops->set_voltage_sel) {
3769                 ret = -EINVAL;
3770                 goto out;
3771         }
3772
3773         /* constraints check */
3774         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3775         if (ret < 0)
3776                 goto out;
3777
3778         /* restore original values in case of error */
3779         old_min_uV = voltage->min_uV;
3780         old_max_uV = voltage->max_uV;
3781         voltage->min_uV = min_uV;
3782         voltage->max_uV = max_uV;
3783
3784         /* for not coupled regulators this will just set the voltage */
3785         ret = regulator_balance_voltage(rdev, state);
3786         if (ret < 0) {
3787                 voltage->min_uV = old_min_uV;
3788                 voltage->max_uV = old_max_uV;
3789         }
3790
3791 out:
3792         return ret;
3793 }
3794
3795 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3796                                int max_uV, suspend_state_t state)
3797 {
3798         int best_supply_uV = 0;
3799         int supply_change_uV = 0;
3800         int ret;
3801
3802         if (rdev->supply &&
3803             regulator_ops_is_valid(rdev->supply->rdev,
3804                                    REGULATOR_CHANGE_VOLTAGE) &&
3805             (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3806                                            rdev->desc->ops->get_voltage_sel))) {
3807                 int current_supply_uV;
3808                 int selector;
3809
3810                 selector = regulator_map_voltage(rdev, min_uV, max_uV);
3811                 if (selector < 0) {
3812                         ret = selector;
3813                         goto out;
3814                 }
3815
3816                 best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3817                 if (best_supply_uV < 0) {
3818                         ret = best_supply_uV;
3819                         goto out;
3820                 }
3821
3822                 best_supply_uV += rdev->desc->min_dropout_uV;
3823
3824                 current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3825                 if (current_supply_uV < 0) {
3826                         ret = current_supply_uV;
3827                         goto out;
3828                 }
3829
3830                 supply_change_uV = best_supply_uV - current_supply_uV;
3831         }
3832
3833         if (supply_change_uV > 0) {
3834                 ret = regulator_set_voltage_unlocked(rdev->supply,
3835                                 best_supply_uV, INT_MAX, state);
3836                 if (ret) {
3837                         dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
3838                                 ERR_PTR(ret));
3839                         goto out;
3840                 }
3841         }
3842
3843         if (state == PM_SUSPEND_ON)
3844                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3845         else
3846                 ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3847                                                         max_uV, state);
3848         if (ret < 0)
3849                 goto out;
3850
3851         if (supply_change_uV < 0) {
3852                 ret = regulator_set_voltage_unlocked(rdev->supply,
3853                                 best_supply_uV, INT_MAX, state);
3854                 if (ret)
3855                         dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
3856                                  ERR_PTR(ret));
3857                 /* No need to fail here */
3858                 ret = 0;
3859         }
3860
3861 out:
3862         return ret;
3863 }
3864 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3865
3866 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3867                                         int *current_uV, int *min_uV)
3868 {
3869         struct regulation_constraints *constraints = rdev->constraints;
3870
3871         /* Limit voltage change only if necessary */
3872         if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3873                 return 1;
3874
3875         if (*current_uV < 0) {
3876                 *current_uV = regulator_get_voltage_rdev(rdev);
3877
3878                 if (*current_uV < 0)
3879                         return *current_uV;
3880         }
3881
3882         if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3883                 return 1;
3884
3885         /* Clamp target voltage within the given step */
3886         if (*current_uV < *min_uV)
3887                 *min_uV = min(*current_uV + constraints->max_uV_step,
3888                               *min_uV);
3889         else
3890                 *min_uV = max(*current_uV - constraints->max_uV_step,
3891                               *min_uV);
3892
3893         return 0;
3894 }
3895
3896 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3897                                          int *current_uV,
3898                                          int *min_uV, int *max_uV,
3899                                          suspend_state_t state,
3900                                          int n_coupled)
3901 {
3902         struct coupling_desc *c_desc = &rdev->coupling_desc;
3903         struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3904         struct regulation_constraints *constraints = rdev->constraints;
3905         int desired_min_uV = 0, desired_max_uV = INT_MAX;
3906         int max_current_uV = 0, min_current_uV = INT_MAX;
3907         int highest_min_uV = 0, target_uV, possible_uV;
3908         int i, ret, max_spread;
3909         bool done;
3910
3911         *current_uV = -1;
3912
3913         /*
3914          * If there are no coupled regulators, simply set the voltage
3915          * demanded by consumers.
3916          */
3917         if (n_coupled == 1) {
3918                 /*
3919                  * If consumers don't provide any demands, set voltage
3920                  * to min_uV
3921                  */
3922                 desired_min_uV = constraints->min_uV;
3923                 desired_max_uV = constraints->max_uV;
3924
3925                 ret = regulator_check_consumers(rdev,
3926                                                 &desired_min_uV,
3927                                                 &desired_max_uV, state);
3928                 if (ret < 0)
3929                         return ret;
3930
3931                 possible_uV = desired_min_uV;
3932                 done = true;
3933
3934                 goto finish;
3935         }
3936
3937         /* Find highest min desired voltage */
3938         for (i = 0; i < n_coupled; i++) {
3939                 int tmp_min = 0;
3940                 int tmp_max = INT_MAX;
3941
3942                 lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3943
3944                 ret = regulator_check_consumers(c_rdevs[i],
3945                                                 &tmp_min,
3946                                                 &tmp_max, state);
3947                 if (ret < 0)
3948                         return ret;
3949
3950                 ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3951                 if (ret < 0)
3952                         return ret;
3953
3954                 highest_min_uV = max(highest_min_uV, tmp_min);
3955
3956                 if (i == 0) {
3957                         desired_min_uV = tmp_min;
3958                         desired_max_uV = tmp_max;
3959                 }
3960         }
3961
3962         max_spread = constraints->max_spread[0];
3963
3964         /*
3965          * Let target_uV be equal to the desired one if possible.
3966          * If not, set it to minimum voltage, allowed by other coupled
3967          * regulators.
3968          */
3969         target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3970
3971         /*
3972          * Find min and max voltages, which currently aren't violating
3973          * max_spread.
3974          */
3975         for (i = 1; i < n_coupled; i++) {
3976                 int tmp_act;
3977
3978                 if (!_regulator_is_enabled(c_rdevs[i]))
3979                         continue;
3980
3981                 tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
3982                 if (tmp_act < 0)
3983                         return tmp_act;
3984
3985                 min_current_uV = min(tmp_act, min_current_uV);
3986                 max_current_uV = max(tmp_act, max_current_uV);
3987         }
3988
3989         /* There aren't any other regulators enabled */
3990         if (max_current_uV == 0) {
3991                 possible_uV = target_uV;
3992         } else {
3993                 /*
3994                  * Correct target voltage, so as it currently isn't
3995                  * violating max_spread
3996                  */
3997                 possible_uV = max(target_uV, max_current_uV - max_spread);
3998                 possible_uV = min(possible_uV, min_current_uV + max_spread);
3999         }
4000
4001         if (possible_uV > desired_max_uV)
4002                 return -EINVAL;
4003
4004         done = (possible_uV == target_uV);
4005         desired_min_uV = possible_uV;
4006
4007 finish:
4008         /* Apply max_uV_step constraint if necessary */
4009         if (state == PM_SUSPEND_ON) {
4010                 ret = regulator_limit_voltage_step(rdev, current_uV,
4011                                                    &desired_min_uV);
4012                 if (ret < 0)
4013                         return ret;
4014
4015                 if (ret == 0)
4016                         done = false;
4017         }
4018
4019         /* Set current_uV if wasn't done earlier in the code and if necessary */
4020         if (n_coupled > 1 && *current_uV == -1) {
4021
4022                 if (_regulator_is_enabled(rdev)) {
4023                         ret = regulator_get_voltage_rdev(rdev);
4024                         if (ret < 0)
4025                                 return ret;
4026
4027                         *current_uV = ret;
4028                 } else {
4029                         *current_uV = desired_min_uV;
4030                 }
4031         }
4032
4033         *min_uV = desired_min_uV;
4034         *max_uV = desired_max_uV;
4035
4036         return done;
4037 }
4038
4039 int regulator_do_balance_voltage(struct regulator_dev *rdev,
4040                                  suspend_state_t state, bool skip_coupled)
4041 {
4042         struct regulator_dev **c_rdevs;
4043         struct regulator_dev *best_rdev;
4044         struct coupling_desc *c_desc = &rdev->coupling_desc;
4045         int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
4046         unsigned int delta, best_delta;
4047         unsigned long c_rdev_done = 0;
4048         bool best_c_rdev_done;
4049
4050         c_rdevs = c_desc->coupled_rdevs;
4051         n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
4052
4053         /*
4054          * Find the best possible voltage change on each loop. Leave the loop
4055          * if there isn't any possible change.
4056          */
4057         do {
4058                 best_c_rdev_done = false;
4059                 best_delta = 0;
4060                 best_min_uV = 0;
4061                 best_max_uV = 0;
4062                 best_c_rdev = 0;
4063                 best_rdev = NULL;
4064
4065                 /*
4066                  * Find highest difference between optimal voltage
4067                  * and current voltage.
4068                  */
4069                 for (i = 0; i < n_coupled; i++) {
4070                         /*
4071                          * optimal_uV is the best voltage that can be set for
4072                          * i-th regulator at the moment without violating
4073                          * max_spread constraint in order to balance
4074                          * the coupled voltages.
4075                          */
4076                         int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
4077
4078                         if (test_bit(i, &c_rdev_done))
4079                                 continue;
4080
4081                         ret = regulator_get_optimal_voltage(c_rdevs[i],
4082                                                             &current_uV,
4083                                                             &optimal_uV,
4084                                                             &optimal_max_uV,
4085                                                             state, n_coupled);
4086                         if (ret < 0)
4087                                 goto out;
4088
4089                         delta = abs(optimal_uV - current_uV);
4090
4091                         if (delta && best_delta <= delta) {
4092                                 best_c_rdev_done = ret;
4093                                 best_delta = delta;
4094                                 best_rdev = c_rdevs[i];
4095                                 best_min_uV = optimal_uV;
4096                                 best_max_uV = optimal_max_uV;
4097                                 best_c_rdev = i;
4098                         }
4099                 }
4100
4101                 /* Nothing to change, return successfully */
4102                 if (!best_rdev) {
4103                         ret = 0;
4104                         goto out;
4105                 }
4106
4107                 ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
4108                                                  best_max_uV, state);
4109
4110                 if (ret < 0)
4111                         goto out;
4112
4113                 if (best_c_rdev_done)
4114                         set_bit(best_c_rdev, &c_rdev_done);
4115
4116         } while (n_coupled > 1);
4117
4118 out:
4119         return ret;
4120 }
4121
4122 static int regulator_balance_voltage(struct regulator_dev *rdev,
4123                                      suspend_state_t state)
4124 {
4125         struct coupling_desc *c_desc = &rdev->coupling_desc;
4126         struct regulator_coupler *coupler = c_desc->coupler;
4127         bool skip_coupled = false;
4128
4129         /*
4130          * If system is in a state other than PM_SUSPEND_ON, don't check
4131          * other coupled regulators.
4132          */
4133         if (state != PM_SUSPEND_ON)
4134                 skip_coupled = true;
4135
4136         if (c_desc->n_resolved < c_desc->n_coupled) {
4137                 rdev_err(rdev, "Not all coupled regulators registered\n");
4138                 return -EPERM;
4139         }
4140
4141         /* Invoke custom balancer for customized couplers */
4142         if (coupler && coupler->balance_voltage)
4143                 return coupler->balance_voltage(coupler, rdev, state);
4144
4145         return regulator_do_balance_voltage(rdev, state, skip_coupled);
4146 }
4147
4148 /**
4149  * regulator_set_voltage - set regulator output voltage
4150  * @regulator: regulator source
4151  * @min_uV: Minimum required voltage in uV
4152  * @max_uV: Maximum acceptable voltage in uV
4153  *
4154  * Sets a voltage regulator to the desired output voltage. This can be set
4155  * during any regulator state. IOW, regulator can be disabled or enabled.
4156  *
4157  * If the regulator is enabled then the voltage will change to the new value
4158  * immediately otherwise if the regulator is disabled the regulator will
4159  * output at the new voltage when enabled.
4160  *
4161  * NOTE: If the regulator is shared between several devices then the lowest
4162  * request voltage that meets the system constraints will be used.
4163  * Regulator system constraints must be set for this regulator before
4164  * calling this function otherwise this call will fail.
4165  */
4166 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
4167 {
4168         struct ww_acquire_ctx ww_ctx;
4169         int ret;
4170
4171         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4172
4173         ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
4174                                              PM_SUSPEND_ON);
4175
4176         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4177
4178         return ret;
4179 }
4180 EXPORT_SYMBOL_GPL(regulator_set_voltage);
4181
4182 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
4183                                            suspend_state_t state, bool en)
4184 {
4185         struct regulator_state *rstate;
4186
4187         rstate = regulator_get_suspend_state(rdev, state);
4188         if (rstate == NULL)
4189                 return -EINVAL;
4190
4191         if (!rstate->changeable)
4192                 return -EPERM;
4193
4194         rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
4195
4196         return 0;
4197 }
4198
4199 int regulator_suspend_enable(struct regulator_dev *rdev,
4200                                     suspend_state_t state)
4201 {
4202         return regulator_suspend_toggle(rdev, state, true);
4203 }
4204 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
4205
4206 int regulator_suspend_disable(struct regulator_dev *rdev,
4207                                      suspend_state_t state)
4208 {
4209         struct regulator *regulator;
4210         struct regulator_voltage *voltage;
4211
4212         /*
4213          * if any consumer wants this regulator device keeping on in
4214          * suspend states, don't set it as disabled.
4215          */
4216         list_for_each_entry(regulator, &rdev->consumer_list, list) {
4217                 voltage = &regulator->voltage[state];
4218                 if (voltage->min_uV || voltage->max_uV)
4219                         return 0;
4220         }
4221
4222         return regulator_suspend_toggle(rdev, state, false);
4223 }
4224 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
4225
4226 static int _regulator_set_suspend_voltage(struct regulator *regulator,
4227                                           int min_uV, int max_uV,
4228                                           suspend_state_t state)
4229 {
4230         struct regulator_dev *rdev = regulator->rdev;
4231         struct regulator_state *rstate;
4232
4233         rstate = regulator_get_suspend_state(rdev, state);
4234         if (rstate == NULL)
4235                 return -EINVAL;
4236
4237         if (rstate->min_uV == rstate->max_uV) {
4238                 rdev_err(rdev, "The suspend voltage can't be changed!\n");
4239                 return -EPERM;
4240         }
4241
4242         return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
4243 }
4244
4245 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
4246                                   int max_uV, suspend_state_t state)
4247 {
4248         struct ww_acquire_ctx ww_ctx;
4249         int ret;
4250
4251         /* PM_SUSPEND_ON is handled by regulator_set_voltage() */
4252         if (regulator_check_states(state) || state == PM_SUSPEND_ON)
4253                 return -EINVAL;
4254
4255         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4256
4257         ret = _regulator_set_suspend_voltage(regulator, min_uV,
4258                                              max_uV, state);
4259
4260         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4261
4262         return ret;
4263 }
4264 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
4265
4266 /**
4267  * regulator_set_voltage_time - get raise/fall time
4268  * @regulator: regulator source
4269  * @old_uV: starting voltage in microvolts
4270  * @new_uV: target voltage in microvolts
4271  *
4272  * Provided with the starting and ending voltage, this function attempts to
4273  * calculate the time in microseconds required to rise or fall to this new
4274  * voltage.
4275  */
4276 int regulator_set_voltage_time(struct regulator *regulator,
4277                                int old_uV, int new_uV)
4278 {
4279         struct regulator_dev *rdev = regulator->rdev;
4280         const struct regulator_ops *ops = rdev->desc->ops;
4281         int old_sel = -1;
4282         int new_sel = -1;
4283         int voltage;
4284         int i;
4285
4286         if (ops->set_voltage_time)
4287                 return ops->set_voltage_time(rdev, old_uV, new_uV);
4288         else if (!ops->set_voltage_time_sel)
4289                 return _regulator_set_voltage_time(rdev, old_uV, new_uV);
4290
4291         /* Currently requires operations to do this */
4292         if (!ops->list_voltage || !rdev->desc->n_voltages)
4293                 return -EINVAL;
4294
4295         for (i = 0; i < rdev->desc->n_voltages; i++) {
4296                 /* We only look for exact voltage matches here */
4297                 if (i < rdev->desc->linear_min_sel)
4298                         continue;
4299
4300                 if (old_sel >= 0 && new_sel >= 0)
4301                         break;
4302
4303                 voltage = regulator_list_voltage(regulator, i);
4304                 if (voltage < 0)
4305                         return -EINVAL;
4306                 if (voltage == 0)
4307                         continue;
4308                 if (voltage == old_uV)
4309                         old_sel = i;
4310                 if (voltage == new_uV)
4311                         new_sel = i;
4312         }
4313
4314         if (old_sel < 0 || new_sel < 0)
4315                 return -EINVAL;
4316
4317         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
4318 }
4319 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
4320
4321 /**
4322  * regulator_set_voltage_time_sel - get raise/fall time
4323  * @rdev: regulator source device
4324  * @old_selector: selector for starting voltage
4325  * @new_selector: selector for target voltage
4326  *
4327  * Provided with the starting and target voltage selectors, this function
4328  * returns time in microseconds required to rise or fall to this new voltage
4329  *
4330  * Drivers providing ramp_delay in regulation_constraints can use this as their
4331  * set_voltage_time_sel() operation.
4332  */
4333 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
4334                                    unsigned int old_selector,
4335                                    unsigned int new_selector)
4336 {
4337         int old_volt, new_volt;
4338
4339         /* sanity check */
4340         if (!rdev->desc->ops->list_voltage)
4341                 return -EINVAL;
4342
4343         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
4344         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
4345
4346         if (rdev->desc->ops->set_voltage_time)
4347                 return rdev->desc->ops->set_voltage_time(rdev, old_volt,
4348                                                          new_volt);
4349         else
4350                 return _regulator_set_voltage_time(rdev, old_volt, new_volt);
4351 }
4352 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
4353
4354 int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
4355 {
4356         int ret;
4357
4358         regulator_lock(rdev);
4359
4360         if (!rdev->desc->ops->set_voltage &&
4361             !rdev->desc->ops->set_voltage_sel) {
4362                 ret = -EINVAL;
4363                 goto out;
4364         }
4365
4366         /* balance only, if regulator is coupled */
4367         if (rdev->coupling_desc.n_coupled > 1)
4368                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4369         else
4370                 ret = -EOPNOTSUPP;
4371
4372 out:
4373         regulator_unlock(rdev);
4374         return ret;
4375 }
4376
4377 /**
4378  * regulator_sync_voltage - re-apply last regulator output voltage
4379  * @regulator: regulator source
4380  *
4381  * Re-apply the last configured voltage.  This is intended to be used
4382  * where some external control source the consumer is cooperating with
4383  * has caused the configured voltage to change.
4384  */
4385 int regulator_sync_voltage(struct regulator *regulator)
4386 {
4387         struct regulator_dev *rdev = regulator->rdev;
4388         struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
4389         int ret, min_uV, max_uV;
4390
4391         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
4392                 return 0;
4393
4394         regulator_lock(rdev);
4395
4396         if (!rdev->desc->ops->set_voltage &&
4397             !rdev->desc->ops->set_voltage_sel) {
4398                 ret = -EINVAL;
4399                 goto out;
4400         }
4401
4402         /* This is only going to work if we've had a voltage configured. */
4403         if (!voltage->min_uV && !voltage->max_uV) {
4404                 ret = -EINVAL;
4405                 goto out;
4406         }
4407
4408         min_uV = voltage->min_uV;
4409         max_uV = voltage->max_uV;
4410
4411         /* This should be a paranoia check... */
4412         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
4413         if (ret < 0)
4414                 goto out;
4415
4416         ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
4417         if (ret < 0)
4418                 goto out;
4419
4420         /* balance only, if regulator is coupled */
4421         if (rdev->coupling_desc.n_coupled > 1)
4422                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4423         else
4424                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
4425
4426 out:
4427         regulator_unlock(rdev);
4428         return ret;
4429 }
4430 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4431
4432 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4433 {
4434         int sel, ret;
4435         bool bypassed;
4436
4437         if (rdev->desc->ops->get_bypass) {
4438                 ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4439                 if (ret < 0)
4440                         return ret;
4441                 if (bypassed) {
4442                         /* if bypassed the regulator must have a supply */
4443                         if (!rdev->supply) {
4444                                 rdev_err(rdev,
4445                                          "bypassed regulator has no supply!\n");
4446                                 return -EPROBE_DEFER;
4447                         }
4448
4449                         return regulator_get_voltage_rdev(rdev->supply->rdev);
4450                 }
4451         }
4452
4453         if (rdev->desc->ops->get_voltage_sel) {
4454                 sel = rdev->desc->ops->get_voltage_sel(rdev);
4455                 if (sel < 0)
4456                         return sel;
4457                 ret = rdev->desc->ops->list_voltage(rdev, sel);
4458         } else if (rdev->desc->ops->get_voltage) {
4459                 ret = rdev->desc->ops->get_voltage(rdev);
4460         } else if (rdev->desc->ops->list_voltage) {
4461                 ret = rdev->desc->ops->list_voltage(rdev, 0);
4462         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4463                 ret = rdev->desc->fixed_uV;
4464         } else if (rdev->supply) {
4465                 ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4466         } else if (rdev->supply_name) {
4467                 return -EPROBE_DEFER;
4468         } else {
4469                 return -EINVAL;
4470         }
4471
4472         if (ret < 0)
4473                 return ret;
4474         return ret - rdev->constraints->uV_offset;
4475 }
4476 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4477
4478 /**
4479  * regulator_get_voltage - get regulator output voltage
4480  * @regulator: regulator source
4481  *
4482  * This returns the current regulator voltage in uV.
4483  *
4484  * NOTE: If the regulator is disabled it will return the voltage value. This
4485  * function should not be used to determine regulator state.
4486  */
4487 int regulator_get_voltage(struct regulator *regulator)
4488 {
4489         struct ww_acquire_ctx ww_ctx;
4490         int ret;
4491
4492         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4493         ret = regulator_get_voltage_rdev(regulator->rdev);
4494         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4495
4496         return ret;
4497 }
4498 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4499
4500 /**
4501  * regulator_set_current_limit - set regulator output current limit
4502  * @regulator: regulator source
4503  * @min_uA: Minimum supported current in uA
4504  * @max_uA: Maximum supported current in uA
4505  *
4506  * Sets current sink to the desired output current. This can be set during
4507  * any regulator state. IOW, regulator can be disabled or enabled.
4508  *
4509  * If the regulator is enabled then the current will change to the new value
4510  * immediately otherwise if the regulator is disabled the regulator will
4511  * output at the new current when enabled.
4512  *
4513  * NOTE: Regulator system constraints must be set for this regulator before
4514  * calling this function otherwise this call will fail.
4515  */
4516 int regulator_set_current_limit(struct regulator *regulator,
4517                                int min_uA, int max_uA)
4518 {
4519         struct regulator_dev *rdev = regulator->rdev;
4520         int ret;
4521
4522         regulator_lock(rdev);
4523
4524         /* sanity check */
4525         if (!rdev->desc->ops->set_current_limit) {
4526                 ret = -EINVAL;
4527                 goto out;
4528         }
4529
4530         /* constraints check */
4531         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4532         if (ret < 0)
4533                 goto out;
4534
4535         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4536 out:
4537         regulator_unlock(rdev);
4538         return ret;
4539 }
4540 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4541
4542 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4543 {
4544         /* sanity check */
4545         if (!rdev->desc->ops->get_current_limit)
4546                 return -EINVAL;
4547
4548         return rdev->desc->ops->get_current_limit(rdev);
4549 }
4550
4551 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4552 {
4553         int ret;
4554
4555         regulator_lock(rdev);
4556         ret = _regulator_get_current_limit_unlocked(rdev);
4557         regulator_unlock(rdev);
4558
4559         return ret;
4560 }
4561
4562 /**
4563  * regulator_get_current_limit - get regulator output current
4564  * @regulator: regulator source
4565  *
4566  * This returns the current supplied by the specified current sink in uA.
4567  *
4568  * NOTE: If the regulator is disabled it will return the current value. This
4569  * function should not be used to determine regulator state.
4570  */
4571 int regulator_get_current_limit(struct regulator *regulator)
4572 {
4573         return _regulator_get_current_limit(regulator->rdev);
4574 }
4575 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4576
4577 /**
4578  * regulator_set_mode - set regulator operating mode
4579  * @regulator: regulator source
4580  * @mode: operating mode - one of the REGULATOR_MODE constants
4581  *
4582  * Set regulator operating mode to increase regulator efficiency or improve
4583  * regulation performance.
4584  *
4585  * NOTE: Regulator system constraints must be set for this regulator before
4586  * calling this function otherwise this call will fail.
4587  */
4588 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4589 {
4590         struct regulator_dev *rdev = regulator->rdev;
4591         int ret;
4592         int regulator_curr_mode;
4593
4594         regulator_lock(rdev);
4595
4596         /* sanity check */
4597         if (!rdev->desc->ops->set_mode) {
4598                 ret = -EINVAL;
4599                 goto out;
4600         }
4601
4602         /* return if the same mode is requested */
4603         if (rdev->desc->ops->get_mode) {
4604                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4605                 if (regulator_curr_mode == mode) {
4606                         ret = 0;
4607                         goto out;
4608                 }
4609         }
4610
4611         /* constraints check */
4612         ret = regulator_mode_constrain(rdev, &mode);
4613         if (ret < 0)
4614                 goto out;
4615
4616         ret = rdev->desc->ops->set_mode(rdev, mode);
4617 out:
4618         regulator_unlock(rdev);
4619         return ret;
4620 }
4621 EXPORT_SYMBOL_GPL(regulator_set_mode);
4622
4623 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4624 {
4625         /* sanity check */
4626         if (!rdev->desc->ops->get_mode)
4627                 return -EINVAL;
4628
4629         return rdev->desc->ops->get_mode(rdev);
4630 }
4631
4632 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4633 {
4634         int ret;
4635
4636         regulator_lock(rdev);
4637         ret = _regulator_get_mode_unlocked(rdev);
4638         regulator_unlock(rdev);
4639
4640         return ret;
4641 }
4642
4643 /**
4644  * regulator_get_mode - get regulator operating mode
4645  * @regulator: regulator source
4646  *
4647  * Get the current regulator operating mode.
4648  */
4649 unsigned int regulator_get_mode(struct regulator *regulator)
4650 {
4651         return _regulator_get_mode(regulator->rdev);
4652 }
4653 EXPORT_SYMBOL_GPL(regulator_get_mode);
4654
4655 static int rdev_get_cached_err_flags(struct regulator_dev *rdev)
4656 {
4657         int ret = 0;
4658
4659         if (rdev->use_cached_err) {
4660                 spin_lock(&rdev->err_lock);
4661                 ret = rdev->cached_err;
4662                 spin_unlock(&rdev->err_lock);
4663         }
4664         return ret;
4665 }
4666
4667 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4668                                         unsigned int *flags)
4669 {
4670         int cached_flags, ret = 0;
4671
4672         regulator_lock(rdev);
4673
4674         cached_flags = rdev_get_cached_err_flags(rdev);
4675
4676         if (rdev->desc->ops->get_error_flags)
4677                 ret = rdev->desc->ops->get_error_flags(rdev, flags);
4678         else if (!rdev->use_cached_err)
4679                 ret = -EINVAL;
4680
4681         *flags |= cached_flags;
4682
4683         regulator_unlock(rdev);
4684
4685         return ret;
4686 }
4687
4688 /**
4689  * regulator_get_error_flags - get regulator error information
4690  * @regulator: regulator source
4691  * @flags: pointer to store error flags
4692  *
4693  * Get the current regulator error information.
4694  */
4695 int regulator_get_error_flags(struct regulator *regulator,
4696                                 unsigned int *flags)
4697 {
4698         return _regulator_get_error_flags(regulator->rdev, flags);
4699 }
4700 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4701
4702 /**
4703  * regulator_set_load - set regulator load
4704  * @regulator: regulator source
4705  * @uA_load: load current
4706  *
4707  * Notifies the regulator core of a new device load. This is then used by
4708  * DRMS (if enabled by constraints) to set the most efficient regulator
4709  * operating mode for the new regulator loading.
4710  *
4711  * Consumer devices notify their supply regulator of the maximum power
4712  * they will require (can be taken from device datasheet in the power
4713  * consumption tables) when they change operational status and hence power
4714  * state. Examples of operational state changes that can affect power
4715  * consumption are :-
4716  *
4717  *    o Device is opened / closed.
4718  *    o Device I/O is about to begin or has just finished.
4719  *    o Device is idling in between work.
4720  *
4721  * This information is also exported via sysfs to userspace.
4722  *
4723  * DRMS will sum the total requested load on the regulator and change
4724  * to the most efficient operating mode if platform constraints allow.
4725  *
4726  * NOTE: when a regulator consumer requests to have a regulator
4727  * disabled then any load that consumer requested no longer counts
4728  * toward the total requested load.  If the regulator is re-enabled
4729  * then the previously requested load will start counting again.
4730  *
4731  * If a regulator is an always-on regulator then an individual consumer's
4732  * load will still be removed if that consumer is fully disabled.
4733  *
4734  * On error a negative errno is returned.
4735  */
4736 int regulator_set_load(struct regulator *regulator, int uA_load)
4737 {
4738         struct regulator_dev *rdev = regulator->rdev;
4739         int old_uA_load;
4740         int ret = 0;
4741
4742         regulator_lock(rdev);
4743         old_uA_load = regulator->uA_load;
4744         regulator->uA_load = uA_load;
4745         if (regulator->enable_count && old_uA_load != uA_load) {
4746                 ret = drms_uA_update(rdev);
4747                 if (ret < 0)
4748                         regulator->uA_load = old_uA_load;
4749         }
4750         regulator_unlock(rdev);
4751
4752         return ret;
4753 }
4754 EXPORT_SYMBOL_GPL(regulator_set_load);
4755
4756 /**
4757  * regulator_allow_bypass - allow the regulator to go into bypass mode
4758  *
4759  * @regulator: Regulator to configure
4760  * @enable: enable or disable bypass mode
4761  *
4762  * Allow the regulator to go into bypass mode if all other consumers
4763  * for the regulator also enable bypass mode and the machine
4764  * constraints allow this.  Bypass mode means that the regulator is
4765  * simply passing the input directly to the output with no regulation.
4766  */
4767 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4768 {
4769         struct regulator_dev *rdev = regulator->rdev;
4770         const char *name = rdev_get_name(rdev);
4771         int ret = 0;
4772
4773         if (!rdev->desc->ops->set_bypass)
4774                 return 0;
4775
4776         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4777                 return 0;
4778
4779         regulator_lock(rdev);
4780
4781         if (enable && !regulator->bypass) {
4782                 rdev->bypass_count++;
4783
4784                 if (rdev->bypass_count == rdev->open_count) {
4785                         trace_regulator_bypass_enable(name);
4786
4787                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4788                         if (ret != 0)
4789                                 rdev->bypass_count--;
4790                         else
4791                                 trace_regulator_bypass_enable_complete(name);
4792                 }
4793
4794         } else if (!enable && regulator->bypass) {
4795                 rdev->bypass_count--;
4796
4797                 if (rdev->bypass_count != rdev->open_count) {
4798                         trace_regulator_bypass_disable(name);
4799
4800                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4801                         if (ret != 0)
4802                                 rdev->bypass_count++;
4803                         else
4804                                 trace_regulator_bypass_disable_complete(name);
4805                 }
4806         }
4807
4808         if (ret == 0)
4809                 regulator->bypass = enable;
4810
4811         regulator_unlock(rdev);
4812
4813         return ret;
4814 }
4815 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4816
4817 /**
4818  * regulator_register_notifier - register regulator event notifier
4819  * @regulator: regulator source
4820  * @nb: notifier block
4821  *
4822  * Register notifier block to receive regulator events.
4823  */
4824 int regulator_register_notifier(struct regulator *regulator,
4825                               struct notifier_block *nb)
4826 {
4827         return blocking_notifier_chain_register(&regulator->rdev->notifier,
4828                                                 nb);
4829 }
4830 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4831
4832 /**
4833  * regulator_unregister_notifier - unregister regulator event notifier
4834  * @regulator: regulator source
4835  * @nb: notifier block
4836  *
4837  * Unregister regulator event notifier block.
4838  */
4839 int regulator_unregister_notifier(struct regulator *regulator,
4840                                 struct notifier_block *nb)
4841 {
4842         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4843                                                   nb);
4844 }
4845 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4846
4847 /* notify regulator consumers and downstream regulator consumers.
4848  * Note mutex must be held by caller.
4849  */
4850 static int _notifier_call_chain(struct regulator_dev *rdev,
4851                                   unsigned long event, void *data)
4852 {
4853         /* call rdev chain first */
4854         return blocking_notifier_call_chain(&rdev->notifier, event, data);
4855 }
4856
4857 int _regulator_bulk_get(struct device *dev, int num_consumers,
4858                         struct regulator_bulk_data *consumers, enum regulator_get_type get_type)
4859 {
4860         int i;
4861         int ret;
4862
4863         for (i = 0; i < num_consumers; i++)
4864                 consumers[i].consumer = NULL;
4865
4866         for (i = 0; i < num_consumers; i++) {
4867                 consumers[i].consumer = _regulator_get(dev,
4868                                                        consumers[i].supply, get_type);
4869                 if (IS_ERR(consumers[i].consumer)) {
4870                         ret = dev_err_probe(dev, PTR_ERR(consumers[i].consumer),
4871                                             "Failed to get supply '%s'",
4872                                             consumers[i].supply);
4873                         consumers[i].consumer = NULL;
4874                         goto err;
4875                 }
4876
4877                 if (consumers[i].init_load_uA > 0) {
4878                         ret = regulator_set_load(consumers[i].consumer,
4879                                                  consumers[i].init_load_uA);
4880                         if (ret) {
4881                                 i++;
4882                                 goto err;
4883                         }
4884                 }
4885         }
4886
4887         return 0;
4888
4889 err:
4890         while (--i >= 0)
4891                 regulator_put(consumers[i].consumer);
4892
4893         return ret;
4894 }
4895
4896 /**
4897  * regulator_bulk_get - get multiple regulator consumers
4898  *
4899  * @dev:           Device to supply
4900  * @num_consumers: Number of consumers to register
4901  * @consumers:     Configuration of consumers; clients are stored here.
4902  *
4903  * @return 0 on success, an errno on failure.
4904  *
4905  * This helper function allows drivers to get several regulator
4906  * consumers in one operation.  If any of the regulators cannot be
4907  * acquired then any regulators that were allocated will be freed
4908  * before returning to the caller.
4909  */
4910 int regulator_bulk_get(struct device *dev, int num_consumers,
4911                        struct regulator_bulk_data *consumers)
4912 {
4913         return _regulator_bulk_get(dev, num_consumers, consumers, NORMAL_GET);
4914 }
4915 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4916
4917 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4918 {
4919         struct regulator_bulk_data *bulk = data;
4920
4921         bulk->ret = regulator_enable(bulk->consumer);
4922 }
4923
4924 /**
4925  * regulator_bulk_enable - enable multiple regulator consumers
4926  *
4927  * @num_consumers: Number of consumers
4928  * @consumers:     Consumer data; clients are stored here.
4929  * @return         0 on success, an errno on failure
4930  *
4931  * This convenience API allows consumers to enable multiple regulator
4932  * clients in a single API call.  If any consumers cannot be enabled
4933  * then any others that were enabled will be disabled again prior to
4934  * return.
4935  */
4936 int regulator_bulk_enable(int num_consumers,
4937                           struct regulator_bulk_data *consumers)
4938 {
4939         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4940         int i;
4941         int ret = 0;
4942
4943         for (i = 0; i < num_consumers; i++) {
4944                 async_schedule_domain(regulator_bulk_enable_async,
4945                                       &consumers[i], &async_domain);
4946         }
4947
4948         async_synchronize_full_domain(&async_domain);
4949
4950         /* If any consumer failed we need to unwind any that succeeded */
4951         for (i = 0; i < num_consumers; i++) {
4952                 if (consumers[i].ret != 0) {
4953                         ret = consumers[i].ret;
4954                         goto err;
4955                 }
4956         }
4957
4958         return 0;
4959
4960 err:
4961         for (i = 0; i < num_consumers; i++) {
4962                 if (consumers[i].ret < 0)
4963                         pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
4964                                ERR_PTR(consumers[i].ret));
4965                 else
4966                         regulator_disable(consumers[i].consumer);
4967         }
4968
4969         return ret;
4970 }
4971 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
4972
4973 /**
4974  * regulator_bulk_disable - disable multiple regulator consumers
4975  *
4976  * @num_consumers: Number of consumers
4977  * @consumers:     Consumer data; clients are stored here.
4978  * @return         0 on success, an errno on failure
4979  *
4980  * This convenience API allows consumers to disable multiple regulator
4981  * clients in a single API call.  If any consumers cannot be disabled
4982  * then any others that were disabled will be enabled again prior to
4983  * return.
4984  */
4985 int regulator_bulk_disable(int num_consumers,
4986                            struct regulator_bulk_data *consumers)
4987 {
4988         int i;
4989         int ret, r;
4990
4991         for (i = num_consumers - 1; i >= 0; --i) {
4992                 ret = regulator_disable(consumers[i].consumer);
4993                 if (ret != 0)
4994                         goto err;
4995         }
4996
4997         return 0;
4998
4999 err:
5000         pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
5001         for (++i; i < num_consumers; ++i) {
5002                 r = regulator_enable(consumers[i].consumer);
5003                 if (r != 0)
5004                         pr_err("Failed to re-enable %s: %pe\n",
5005                                consumers[i].supply, ERR_PTR(r));
5006         }
5007
5008         return ret;
5009 }
5010 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
5011
5012 /**
5013  * regulator_bulk_force_disable - force disable multiple regulator consumers
5014  *
5015  * @num_consumers: Number of consumers
5016  * @consumers:     Consumer data; clients are stored here.
5017  * @return         0 on success, an errno on failure
5018  *
5019  * This convenience API allows consumers to forcibly disable multiple regulator
5020  * clients in a single API call.
5021  * NOTE: This should be used for situations when device damage will
5022  * likely occur if the regulators are not disabled (e.g. over temp).
5023  * Although regulator_force_disable function call for some consumers can
5024  * return error numbers, the function is called for all consumers.
5025  */
5026 int regulator_bulk_force_disable(int num_consumers,
5027                            struct regulator_bulk_data *consumers)
5028 {
5029         int i;
5030         int ret = 0;
5031
5032         for (i = 0; i < num_consumers; i++) {
5033                 consumers[i].ret =
5034                             regulator_force_disable(consumers[i].consumer);
5035
5036                 /* Store first error for reporting */
5037                 if (consumers[i].ret && !ret)
5038                         ret = consumers[i].ret;
5039         }
5040
5041         return ret;
5042 }
5043 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
5044
5045 /**
5046  * regulator_bulk_free - free multiple regulator consumers
5047  *
5048  * @num_consumers: Number of consumers
5049  * @consumers:     Consumer data; clients are stored here.
5050  *
5051  * This convenience API allows consumers to free multiple regulator
5052  * clients in a single API call.
5053  */
5054 void regulator_bulk_free(int num_consumers,
5055                          struct regulator_bulk_data *consumers)
5056 {
5057         int i;
5058
5059         for (i = 0; i < num_consumers; i++) {
5060                 regulator_put(consumers[i].consumer);
5061                 consumers[i].consumer = NULL;
5062         }
5063 }
5064 EXPORT_SYMBOL_GPL(regulator_bulk_free);
5065
5066 /**
5067  * regulator_notifier_call_chain - call regulator event notifier
5068  * @rdev: regulator source
5069  * @event: notifier block
5070  * @data: callback-specific data.
5071  *
5072  * Called by regulator drivers to notify clients a regulator event has
5073  * occurred.
5074  */
5075 int regulator_notifier_call_chain(struct regulator_dev *rdev,
5076                                   unsigned long event, void *data)
5077 {
5078         _notifier_call_chain(rdev, event, data);
5079         return NOTIFY_DONE;
5080
5081 }
5082 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
5083
5084 /**
5085  * regulator_mode_to_status - convert a regulator mode into a status
5086  *
5087  * @mode: Mode to convert
5088  *
5089  * Convert a regulator mode into a status.
5090  */
5091 int regulator_mode_to_status(unsigned int mode)
5092 {
5093         switch (mode) {
5094         case REGULATOR_MODE_FAST:
5095                 return REGULATOR_STATUS_FAST;
5096         case REGULATOR_MODE_NORMAL:
5097                 return REGULATOR_STATUS_NORMAL;
5098         case REGULATOR_MODE_IDLE:
5099                 return REGULATOR_STATUS_IDLE;
5100         case REGULATOR_MODE_STANDBY:
5101                 return REGULATOR_STATUS_STANDBY;
5102         default:
5103                 return REGULATOR_STATUS_UNDEFINED;
5104         }
5105 }
5106 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
5107
5108 static struct attribute *regulator_dev_attrs[] = {
5109         &dev_attr_name.attr,
5110         &dev_attr_num_users.attr,
5111         &dev_attr_type.attr,
5112         &dev_attr_microvolts.attr,
5113         &dev_attr_microamps.attr,
5114         &dev_attr_opmode.attr,
5115         &dev_attr_state.attr,
5116         &dev_attr_status.attr,
5117         &dev_attr_bypass.attr,
5118         &dev_attr_requested_microamps.attr,
5119         &dev_attr_min_microvolts.attr,
5120         &dev_attr_max_microvolts.attr,
5121         &dev_attr_min_microamps.attr,
5122         &dev_attr_max_microamps.attr,
5123         &dev_attr_under_voltage.attr,
5124         &dev_attr_over_current.attr,
5125         &dev_attr_regulation_out.attr,
5126         &dev_attr_fail.attr,
5127         &dev_attr_over_temp.attr,
5128         &dev_attr_under_voltage_warn.attr,
5129         &dev_attr_over_current_warn.attr,
5130         &dev_attr_over_voltage_warn.attr,
5131         &dev_attr_over_temp_warn.attr,
5132         &dev_attr_suspend_standby_state.attr,
5133         &dev_attr_suspend_mem_state.attr,
5134         &dev_attr_suspend_disk_state.attr,
5135         &dev_attr_suspend_standby_microvolts.attr,
5136         &dev_attr_suspend_mem_microvolts.attr,
5137         &dev_attr_suspend_disk_microvolts.attr,
5138         &dev_attr_suspend_standby_mode.attr,
5139         &dev_attr_suspend_mem_mode.attr,
5140         &dev_attr_suspend_disk_mode.attr,
5141         NULL
5142 };
5143
5144 /*
5145  * To avoid cluttering sysfs (and memory) with useless state, only
5146  * create attributes that can be meaningfully displayed.
5147  */
5148 static umode_t regulator_attr_is_visible(struct kobject *kobj,
5149                                          struct attribute *attr, int idx)
5150 {
5151         struct device *dev = kobj_to_dev(kobj);
5152         struct regulator_dev *rdev = dev_to_rdev(dev);
5153         const struct regulator_ops *ops = rdev->desc->ops;
5154         umode_t mode = attr->mode;
5155
5156         /* these three are always present */
5157         if (attr == &dev_attr_name.attr ||
5158             attr == &dev_attr_num_users.attr ||
5159             attr == &dev_attr_type.attr)
5160                 return mode;
5161
5162         /* some attributes need specific methods to be displayed */
5163         if (attr == &dev_attr_microvolts.attr) {
5164                 if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
5165                     (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
5166                     (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
5167                     (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
5168                         return mode;
5169                 return 0;
5170         }
5171
5172         if (attr == &dev_attr_microamps.attr)
5173                 return ops->get_current_limit ? mode : 0;
5174
5175         if (attr == &dev_attr_opmode.attr)
5176                 return ops->get_mode ? mode : 0;
5177
5178         if (attr == &dev_attr_state.attr)
5179                 return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
5180
5181         if (attr == &dev_attr_status.attr)
5182                 return ops->get_status ? mode : 0;
5183
5184         if (attr == &dev_attr_bypass.attr)
5185                 return ops->get_bypass ? mode : 0;
5186
5187         if (attr == &dev_attr_under_voltage.attr ||
5188             attr == &dev_attr_over_current.attr ||
5189             attr == &dev_attr_regulation_out.attr ||
5190             attr == &dev_attr_fail.attr ||
5191             attr == &dev_attr_over_temp.attr ||
5192             attr == &dev_attr_under_voltage_warn.attr ||
5193             attr == &dev_attr_over_current_warn.attr ||
5194             attr == &dev_attr_over_voltage_warn.attr ||
5195             attr == &dev_attr_over_temp_warn.attr)
5196                 return ops->get_error_flags ? mode : 0;
5197
5198         /* constraints need specific supporting methods */
5199         if (attr == &dev_attr_min_microvolts.attr ||
5200             attr == &dev_attr_max_microvolts.attr)
5201                 return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
5202
5203         if (attr == &dev_attr_min_microamps.attr ||
5204             attr == &dev_attr_max_microamps.attr)
5205                 return ops->set_current_limit ? mode : 0;
5206
5207         if (attr == &dev_attr_suspend_standby_state.attr ||
5208             attr == &dev_attr_suspend_mem_state.attr ||
5209             attr == &dev_attr_suspend_disk_state.attr)
5210                 return mode;
5211
5212         if (attr == &dev_attr_suspend_standby_microvolts.attr ||
5213             attr == &dev_attr_suspend_mem_microvolts.attr ||
5214             attr == &dev_attr_suspend_disk_microvolts.attr)
5215                 return ops->set_suspend_voltage ? mode : 0;
5216
5217         if (attr == &dev_attr_suspend_standby_mode.attr ||
5218             attr == &dev_attr_suspend_mem_mode.attr ||
5219             attr == &dev_attr_suspend_disk_mode.attr)
5220                 return ops->set_suspend_mode ? mode : 0;
5221
5222         return mode;
5223 }
5224
5225 static const struct attribute_group regulator_dev_group = {
5226         .attrs = regulator_dev_attrs,
5227         .is_visible = regulator_attr_is_visible,
5228 };
5229
5230 static const struct attribute_group *regulator_dev_groups[] = {
5231         &regulator_dev_group,
5232         NULL
5233 };
5234
5235 static void regulator_dev_release(struct device *dev)
5236 {
5237         struct regulator_dev *rdev = dev_get_drvdata(dev);
5238
5239         debugfs_remove_recursive(rdev->debugfs);
5240         kfree(rdev->constraints);
5241         of_node_put(rdev->dev.of_node);
5242         kfree(rdev);
5243 }
5244
5245 static void rdev_init_debugfs(struct regulator_dev *rdev)
5246 {
5247         struct device *parent = rdev->dev.parent;
5248         const char *rname = rdev_get_name(rdev);
5249         char name[NAME_MAX];
5250
5251         /* Avoid duplicate debugfs directory names */
5252         if (parent && rname == rdev->desc->name) {
5253                 snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
5254                          rname);
5255                 rname = name;
5256         }
5257
5258         rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
5259         if (!rdev->debugfs) {
5260                 rdev_warn(rdev, "Failed to create debugfs directory\n");
5261                 return;
5262         }
5263
5264         debugfs_create_u32("use_count", 0444, rdev->debugfs,
5265                            &rdev->use_count);
5266         debugfs_create_u32("open_count", 0444, rdev->debugfs,
5267                            &rdev->open_count);
5268         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
5269                            &rdev->bypass_count);
5270 }
5271
5272 static int regulator_register_resolve_supply(struct device *dev, void *data)
5273 {
5274         struct regulator_dev *rdev = dev_to_rdev(dev);
5275
5276         if (regulator_resolve_supply(rdev))
5277                 rdev_dbg(rdev, "unable to resolve supply\n");
5278
5279         return 0;
5280 }
5281
5282 int regulator_coupler_register(struct regulator_coupler *coupler)
5283 {
5284         mutex_lock(&regulator_list_mutex);
5285         list_add_tail(&coupler->list, &regulator_coupler_list);
5286         mutex_unlock(&regulator_list_mutex);
5287
5288         return 0;
5289 }
5290
5291 static struct regulator_coupler *
5292 regulator_find_coupler(struct regulator_dev *rdev)
5293 {
5294         struct regulator_coupler *coupler;
5295         int err;
5296
5297         /*
5298          * Note that regulators are appended to the list and the generic
5299          * coupler is registered first, hence it will be attached at last
5300          * if nobody cared.
5301          */
5302         list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
5303                 err = coupler->attach_regulator(coupler, rdev);
5304                 if (!err) {
5305                         if (!coupler->balance_voltage &&
5306                             rdev->coupling_desc.n_coupled > 2)
5307                                 goto err_unsupported;
5308
5309                         return coupler;
5310                 }
5311
5312                 if (err < 0)
5313                         return ERR_PTR(err);
5314
5315                 if (err == 1)
5316                         continue;
5317
5318                 break;
5319         }
5320
5321         return ERR_PTR(-EINVAL);
5322
5323 err_unsupported:
5324         if (coupler->detach_regulator)
5325                 coupler->detach_regulator(coupler, rdev);
5326
5327         rdev_err(rdev,
5328                 "Voltage balancing for multiple regulator couples is unimplemented\n");
5329
5330         return ERR_PTR(-EPERM);
5331 }
5332
5333 static void regulator_resolve_coupling(struct regulator_dev *rdev)
5334 {
5335         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5336         struct coupling_desc *c_desc = &rdev->coupling_desc;
5337         int n_coupled = c_desc->n_coupled;
5338         struct regulator_dev *c_rdev;
5339         int i;
5340
5341         for (i = 1; i < n_coupled; i++) {
5342                 /* already resolved */
5343                 if (c_desc->coupled_rdevs[i])
5344                         continue;
5345
5346                 c_rdev = of_parse_coupled_regulator(rdev, i - 1);
5347
5348                 if (!c_rdev)
5349                         continue;
5350
5351                 if (c_rdev->coupling_desc.coupler != coupler) {
5352                         rdev_err(rdev, "coupler mismatch with %s\n",
5353                                  rdev_get_name(c_rdev));
5354                         return;
5355                 }
5356
5357                 c_desc->coupled_rdevs[i] = c_rdev;
5358                 c_desc->n_resolved++;
5359
5360                 regulator_resolve_coupling(c_rdev);
5361         }
5362 }
5363
5364 static void regulator_remove_coupling(struct regulator_dev *rdev)
5365 {
5366         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5367         struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
5368         struct regulator_dev *__c_rdev, *c_rdev;
5369         unsigned int __n_coupled, n_coupled;
5370         int i, k;
5371         int err;
5372
5373         n_coupled = c_desc->n_coupled;
5374
5375         for (i = 1; i < n_coupled; i++) {
5376                 c_rdev = c_desc->coupled_rdevs[i];
5377
5378                 if (!c_rdev)
5379                         continue;
5380
5381                 regulator_lock(c_rdev);
5382
5383                 __c_desc = &c_rdev->coupling_desc;
5384                 __n_coupled = __c_desc->n_coupled;
5385
5386                 for (k = 1; k < __n_coupled; k++) {
5387                         __c_rdev = __c_desc->coupled_rdevs[k];
5388
5389                         if (__c_rdev == rdev) {
5390                                 __c_desc->coupled_rdevs[k] = NULL;
5391                                 __c_desc->n_resolved--;
5392                                 break;
5393                         }
5394                 }
5395
5396                 regulator_unlock(c_rdev);
5397
5398                 c_desc->coupled_rdevs[i] = NULL;
5399                 c_desc->n_resolved--;
5400         }
5401
5402         if (coupler && coupler->detach_regulator) {
5403                 err = coupler->detach_regulator(coupler, rdev);
5404                 if (err)
5405                         rdev_err(rdev, "failed to detach from coupler: %pe\n",
5406                                  ERR_PTR(err));
5407         }
5408
5409         kfree(rdev->coupling_desc.coupled_rdevs);
5410         rdev->coupling_desc.coupled_rdevs = NULL;
5411 }
5412
5413 static int regulator_init_coupling(struct regulator_dev *rdev)
5414 {
5415         struct regulator_dev **coupled;
5416         int err, n_phandles;
5417
5418         if (!IS_ENABLED(CONFIG_OF))
5419                 n_phandles = 0;
5420         else
5421                 n_phandles = of_get_n_coupled(rdev);
5422
5423         coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
5424         if (!coupled)
5425                 return -ENOMEM;
5426
5427         rdev->coupling_desc.coupled_rdevs = coupled;
5428
5429         /*
5430          * Every regulator should always have coupling descriptor filled with
5431          * at least pointer to itself.
5432          */
5433         rdev->coupling_desc.coupled_rdevs[0] = rdev;
5434         rdev->coupling_desc.n_coupled = n_phandles + 1;
5435         rdev->coupling_desc.n_resolved++;
5436
5437         /* regulator isn't coupled */
5438         if (n_phandles == 0)
5439                 return 0;
5440
5441         if (!of_check_coupling_data(rdev))
5442                 return -EPERM;
5443
5444         mutex_lock(&regulator_list_mutex);
5445         rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
5446         mutex_unlock(&regulator_list_mutex);
5447
5448         if (IS_ERR(rdev->coupling_desc.coupler)) {
5449                 err = PTR_ERR(rdev->coupling_desc.coupler);
5450                 rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
5451                 return err;
5452         }
5453
5454         return 0;
5455 }
5456
5457 static int generic_coupler_attach(struct regulator_coupler *coupler,
5458                                   struct regulator_dev *rdev)
5459 {
5460         if (rdev->coupling_desc.n_coupled > 2) {
5461                 rdev_err(rdev,
5462                          "Voltage balancing for multiple regulator couples is unimplemented\n");
5463                 return -EPERM;
5464         }
5465
5466         if (!rdev->constraints->always_on) {
5467                 rdev_err(rdev,
5468                          "Coupling of a non always-on regulator is unimplemented\n");
5469                 return -ENOTSUPP;
5470         }
5471
5472         return 0;
5473 }
5474
5475 static struct regulator_coupler generic_regulator_coupler = {
5476         .attach_regulator = generic_coupler_attach,
5477 };
5478
5479 /**
5480  * regulator_register - register regulator
5481  * @dev: the device that drive the regulator
5482  * @regulator_desc: regulator to register
5483  * @cfg: runtime configuration for regulator
5484  *
5485  * Called by regulator drivers to register a regulator.
5486  * Returns a valid pointer to struct regulator_dev on success
5487  * or an ERR_PTR() on error.
5488  */
5489 struct regulator_dev *
5490 regulator_register(struct device *dev,
5491                    const struct regulator_desc *regulator_desc,
5492                    const struct regulator_config *cfg)
5493 {
5494         const struct regulator_init_data *init_data;
5495         struct regulator_config *config = NULL;
5496         static atomic_t regulator_no = ATOMIC_INIT(-1);
5497         struct regulator_dev *rdev;
5498         bool dangling_cfg_gpiod = false;
5499         bool dangling_of_gpiod = false;
5500         int ret, i;
5501         bool resolved_early = false;
5502
5503         if (cfg == NULL)
5504                 return ERR_PTR(-EINVAL);
5505         if (cfg->ena_gpiod)
5506                 dangling_cfg_gpiod = true;
5507         if (regulator_desc == NULL) {
5508                 ret = -EINVAL;
5509                 goto rinse;
5510         }
5511
5512         WARN_ON(!dev || !cfg->dev);
5513
5514         if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5515                 ret = -EINVAL;
5516                 goto rinse;
5517         }
5518
5519         if (regulator_desc->type != REGULATOR_VOLTAGE &&
5520             regulator_desc->type != REGULATOR_CURRENT) {
5521                 ret = -EINVAL;
5522                 goto rinse;
5523         }
5524
5525         /* Only one of each should be implemented */
5526         WARN_ON(regulator_desc->ops->get_voltage &&
5527                 regulator_desc->ops->get_voltage_sel);
5528         WARN_ON(regulator_desc->ops->set_voltage &&
5529                 regulator_desc->ops->set_voltage_sel);
5530
5531         /* If we're using selectors we must implement list_voltage. */
5532         if (regulator_desc->ops->get_voltage_sel &&
5533             !regulator_desc->ops->list_voltage) {
5534                 ret = -EINVAL;
5535                 goto rinse;
5536         }
5537         if (regulator_desc->ops->set_voltage_sel &&
5538             !regulator_desc->ops->list_voltage) {
5539                 ret = -EINVAL;
5540                 goto rinse;
5541         }
5542
5543         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5544         if (rdev == NULL) {
5545                 ret = -ENOMEM;
5546                 goto rinse;
5547         }
5548         device_initialize(&rdev->dev);
5549         spin_lock_init(&rdev->err_lock);
5550
5551         /*
5552          * Duplicate the config so the driver could override it after
5553          * parsing init data.
5554          */
5555         config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5556         if (config == NULL) {
5557                 ret = -ENOMEM;
5558                 goto clean;
5559         }
5560
5561         init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5562                                                &rdev->dev.of_node);
5563
5564         /*
5565          * Sometimes not all resources are probed already so we need to take
5566          * that into account. This happens most the time if the ena_gpiod comes
5567          * from a gpio extender or something else.
5568          */
5569         if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5570                 ret = -EPROBE_DEFER;
5571                 goto clean;
5572         }
5573
5574         /*
5575          * We need to keep track of any GPIO descriptor coming from the
5576          * device tree until we have handled it over to the core. If the
5577          * config that was passed in to this function DOES NOT contain
5578          * a descriptor, and the config after this call DOES contain
5579          * a descriptor, we definitely got one from parsing the device
5580          * tree.
5581          */
5582         if (!cfg->ena_gpiod && config->ena_gpiod)
5583                 dangling_of_gpiod = true;
5584         if (!init_data) {
5585                 init_data = config->init_data;
5586                 rdev->dev.of_node = of_node_get(config->of_node);
5587         }
5588
5589         ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5590         rdev->reg_data = config->driver_data;
5591         rdev->owner = regulator_desc->owner;
5592         rdev->desc = regulator_desc;
5593         if (config->regmap)
5594                 rdev->regmap = config->regmap;
5595         else if (dev_get_regmap(dev, NULL))
5596                 rdev->regmap = dev_get_regmap(dev, NULL);
5597         else if (dev->parent)
5598                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
5599         INIT_LIST_HEAD(&rdev->consumer_list);
5600         INIT_LIST_HEAD(&rdev->list);
5601         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5602         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5603
5604         if (init_data && init_data->supply_regulator)
5605                 rdev->supply_name = init_data->supply_regulator;
5606         else if (regulator_desc->supply_name)
5607                 rdev->supply_name = regulator_desc->supply_name;
5608
5609         /* register with sysfs */
5610         rdev->dev.class = &regulator_class;
5611         rdev->dev.parent = config->dev;
5612         dev_set_name(&rdev->dev, "regulator.%lu",
5613                     (unsigned long) atomic_inc_return(&regulator_no));
5614         dev_set_drvdata(&rdev->dev, rdev);
5615
5616         /* set regulator constraints */
5617         if (init_data)
5618                 rdev->constraints = kmemdup(&init_data->constraints,
5619                                             sizeof(*rdev->constraints),
5620                                             GFP_KERNEL);
5621         else
5622                 rdev->constraints = kzalloc(sizeof(*rdev->constraints),
5623                                             GFP_KERNEL);
5624         if (!rdev->constraints) {
5625                 ret = -ENOMEM;
5626                 goto wash;
5627         }
5628
5629         if ((rdev->supply_name && !rdev->supply) &&
5630                 (rdev->constraints->always_on ||
5631                  rdev->constraints->boot_on)) {
5632                 ret = regulator_resolve_supply(rdev);
5633                 if (ret)
5634                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5635                                          ERR_PTR(ret));
5636
5637                 resolved_early = true;
5638         }
5639
5640         /* perform any regulator specific init */
5641         if (init_data && init_data->regulator_init) {
5642                 ret = init_data->regulator_init(rdev->reg_data);
5643                 if (ret < 0)
5644                         goto wash;
5645         }
5646
5647         if (config->ena_gpiod) {
5648                 ret = regulator_ena_gpio_request(rdev, config);
5649                 if (ret != 0) {
5650                         rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
5651                                  ERR_PTR(ret));
5652                         goto wash;
5653                 }
5654                 /* The regulator core took over the GPIO descriptor */
5655                 dangling_cfg_gpiod = false;
5656                 dangling_of_gpiod = false;
5657         }
5658
5659         ret = set_machine_constraints(rdev);
5660         if (ret == -EPROBE_DEFER && !resolved_early) {
5661                 /* Regulator might be in bypass mode and so needs its supply
5662                  * to set the constraints
5663                  */
5664                 /* FIXME: this currently triggers a chicken-and-egg problem
5665                  * when creating -SUPPLY symlink in sysfs to a regulator
5666                  * that is just being created
5667                  */
5668                 rdev_dbg(rdev, "will resolve supply early: %s\n",
5669                          rdev->supply_name);
5670                 ret = regulator_resolve_supply(rdev);
5671                 if (!ret)
5672                         ret = set_machine_constraints(rdev);
5673                 else
5674                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5675                                  ERR_PTR(ret));
5676         }
5677         if (ret < 0)
5678                 goto wash;
5679
5680         ret = regulator_init_coupling(rdev);
5681         if (ret < 0)
5682                 goto wash;
5683
5684         /* add consumers devices */
5685         if (init_data) {
5686                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
5687                         ret = set_consumer_device_supply(rdev,
5688                                 init_data->consumer_supplies[i].dev_name,
5689                                 init_data->consumer_supplies[i].supply);
5690                         if (ret < 0) {
5691                                 dev_err(dev, "Failed to set supply %s\n",
5692                                         init_data->consumer_supplies[i].supply);
5693                                 goto unset_supplies;
5694                         }
5695                 }
5696         }
5697
5698         if (!rdev->desc->ops->get_voltage &&
5699             !rdev->desc->ops->list_voltage &&
5700             !rdev->desc->fixed_uV)
5701                 rdev->is_switch = true;
5702
5703         ret = device_add(&rdev->dev);
5704         if (ret != 0)
5705                 goto unset_supplies;
5706
5707         rdev_init_debugfs(rdev);
5708
5709         /* try to resolve regulators coupling since a new one was registered */
5710         mutex_lock(&regulator_list_mutex);
5711         regulator_resolve_coupling(rdev);
5712         mutex_unlock(&regulator_list_mutex);
5713
5714         /* try to resolve regulators supply since a new one was registered */
5715         class_for_each_device(&regulator_class, NULL, NULL,
5716                               regulator_register_resolve_supply);
5717         kfree(config);
5718         return rdev;
5719
5720 unset_supplies:
5721         mutex_lock(&regulator_list_mutex);
5722         unset_regulator_supplies(rdev);
5723         regulator_remove_coupling(rdev);
5724         mutex_unlock(&regulator_list_mutex);
5725 wash:
5726         regulator_put(rdev->supply);
5727         kfree(rdev->coupling_desc.coupled_rdevs);
5728         mutex_lock(&regulator_list_mutex);
5729         regulator_ena_gpio_free(rdev);
5730         mutex_unlock(&regulator_list_mutex);
5731         put_device(&rdev->dev);
5732         rdev = NULL;
5733 clean:
5734         if (dangling_of_gpiod)
5735                 gpiod_put(config->ena_gpiod);
5736         if (rdev && rdev->dev.of_node)
5737                 of_node_put(rdev->dev.of_node);
5738         kfree(rdev);
5739         kfree(config);
5740 rinse:
5741         if (dangling_cfg_gpiod)
5742                 gpiod_put(cfg->ena_gpiod);
5743         return ERR_PTR(ret);
5744 }
5745 EXPORT_SYMBOL_GPL(regulator_register);
5746
5747 /**
5748  * regulator_unregister - unregister regulator
5749  * @rdev: regulator to unregister
5750  *
5751  * Called by regulator drivers to unregister a regulator.
5752  */
5753 void regulator_unregister(struct regulator_dev *rdev)
5754 {
5755         if (rdev == NULL)
5756                 return;
5757
5758         if (rdev->supply) {
5759                 while (rdev->use_count--)
5760                         regulator_disable(rdev->supply);
5761                 regulator_put(rdev->supply);
5762         }
5763
5764         flush_work(&rdev->disable_work.work);
5765
5766         mutex_lock(&regulator_list_mutex);
5767
5768         WARN_ON(rdev->open_count);
5769         regulator_remove_coupling(rdev);
5770         unset_regulator_supplies(rdev);
5771         list_del(&rdev->list);
5772         regulator_ena_gpio_free(rdev);
5773         device_unregister(&rdev->dev);
5774
5775         mutex_unlock(&regulator_list_mutex);
5776 }
5777 EXPORT_SYMBOL_GPL(regulator_unregister);
5778
5779 #ifdef CONFIG_SUSPEND
5780 /**
5781  * regulator_suspend - prepare regulators for system wide suspend
5782  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5783  *
5784  * Configure each regulator with it's suspend operating parameters for state.
5785  */
5786 static int regulator_suspend(struct device *dev)
5787 {
5788         struct regulator_dev *rdev = dev_to_rdev(dev);
5789         suspend_state_t state = pm_suspend_target_state;
5790         int ret;
5791         const struct regulator_state *rstate;
5792
5793         rstate = regulator_get_suspend_state_check(rdev, state);
5794         if (!rstate)
5795                 return 0;
5796
5797         regulator_lock(rdev);
5798         ret = __suspend_set_state(rdev, rstate);
5799         regulator_unlock(rdev);
5800
5801         return ret;
5802 }
5803
5804 static int regulator_resume(struct device *dev)
5805 {
5806         suspend_state_t state = pm_suspend_target_state;
5807         struct regulator_dev *rdev = dev_to_rdev(dev);
5808         struct regulator_state *rstate;
5809         int ret = 0;
5810
5811         rstate = regulator_get_suspend_state(rdev, state);
5812         if (rstate == NULL)
5813                 return 0;
5814
5815         /* Avoid grabbing the lock if we don't need to */
5816         if (!rdev->desc->ops->resume)
5817                 return 0;
5818
5819         regulator_lock(rdev);
5820
5821         if (rstate->enabled == ENABLE_IN_SUSPEND ||
5822             rstate->enabled == DISABLE_IN_SUSPEND)
5823                 ret = rdev->desc->ops->resume(rdev);
5824
5825         regulator_unlock(rdev);
5826
5827         return ret;
5828 }
5829 #else /* !CONFIG_SUSPEND */
5830
5831 #define regulator_suspend       NULL
5832 #define regulator_resume        NULL
5833
5834 #endif /* !CONFIG_SUSPEND */
5835
5836 #ifdef CONFIG_PM
5837 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5838         .suspend        = regulator_suspend,
5839         .resume         = regulator_resume,
5840 };
5841 #endif
5842
5843 struct class regulator_class = {
5844         .name = "regulator",
5845         .dev_release = regulator_dev_release,
5846         .dev_groups = regulator_dev_groups,
5847 #ifdef CONFIG_PM
5848         .pm = &regulator_pm_ops,
5849 #endif
5850 };
5851 /**
5852  * regulator_has_full_constraints - the system has fully specified constraints
5853  *
5854  * Calling this function will cause the regulator API to disable all
5855  * regulators which have a zero use count and don't have an always_on
5856  * constraint in a late_initcall.
5857  *
5858  * The intention is that this will become the default behaviour in a
5859  * future kernel release so users are encouraged to use this facility
5860  * now.
5861  */
5862 void regulator_has_full_constraints(void)
5863 {
5864         has_full_constraints = 1;
5865 }
5866 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5867
5868 /**
5869  * rdev_get_drvdata - get rdev regulator driver data
5870  * @rdev: regulator
5871  *
5872  * Get rdev regulator driver private data. This call can be used in the
5873  * regulator driver context.
5874  */
5875 void *rdev_get_drvdata(struct regulator_dev *rdev)
5876 {
5877         return rdev->reg_data;
5878 }
5879 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5880
5881 /**
5882  * regulator_get_drvdata - get regulator driver data
5883  * @regulator: regulator
5884  *
5885  * Get regulator driver private data. This call can be used in the consumer
5886  * driver context when non API regulator specific functions need to be called.
5887  */
5888 void *regulator_get_drvdata(struct regulator *regulator)
5889 {
5890         return regulator->rdev->reg_data;
5891 }
5892 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5893
5894 /**
5895  * regulator_set_drvdata - set regulator driver data
5896  * @regulator: regulator
5897  * @data: data
5898  */
5899 void regulator_set_drvdata(struct regulator *regulator, void *data)
5900 {
5901         regulator->rdev->reg_data = data;
5902 }
5903 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5904
5905 /**
5906  * rdev_get_id - get regulator ID
5907  * @rdev: regulator
5908  */
5909 int rdev_get_id(struct regulator_dev *rdev)
5910 {
5911         return rdev->desc->id;
5912 }
5913 EXPORT_SYMBOL_GPL(rdev_get_id);
5914
5915 struct device *rdev_get_dev(struct regulator_dev *rdev)
5916 {
5917         return &rdev->dev;
5918 }
5919 EXPORT_SYMBOL_GPL(rdev_get_dev);
5920
5921 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5922 {
5923         return rdev->regmap;
5924 }
5925 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5926
5927 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5928 {
5929         return reg_init_data->driver_data;
5930 }
5931 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5932
5933 #ifdef CONFIG_DEBUG_FS
5934 static int supply_map_show(struct seq_file *sf, void *data)
5935 {
5936         struct regulator_map *map;
5937
5938         list_for_each_entry(map, &regulator_map_list, list) {
5939                 seq_printf(sf, "%s -> %s.%s\n",
5940                                 rdev_get_name(map->regulator), map->dev_name,
5941                                 map->supply);
5942         }
5943
5944         return 0;
5945 }
5946 DEFINE_SHOW_ATTRIBUTE(supply_map);
5947
5948 struct summary_data {
5949         struct seq_file *s;
5950         struct regulator_dev *parent;
5951         int level;
5952 };
5953
5954 static void regulator_summary_show_subtree(struct seq_file *s,
5955                                            struct regulator_dev *rdev,
5956                                            int level);
5957
5958 static int regulator_summary_show_children(struct device *dev, void *data)
5959 {
5960         struct regulator_dev *rdev = dev_to_rdev(dev);
5961         struct summary_data *summary_data = data;
5962
5963         if (rdev->supply && rdev->supply->rdev == summary_data->parent)
5964                 regulator_summary_show_subtree(summary_data->s, rdev,
5965                                                summary_data->level + 1);
5966
5967         return 0;
5968 }
5969
5970 static void regulator_summary_show_subtree(struct seq_file *s,
5971                                            struct regulator_dev *rdev,
5972                                            int level)
5973 {
5974         struct regulation_constraints *c;
5975         struct regulator *consumer;
5976         struct summary_data summary_data;
5977         unsigned int opmode;
5978
5979         if (!rdev)
5980                 return;
5981
5982         opmode = _regulator_get_mode_unlocked(rdev);
5983         seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
5984                    level * 3 + 1, "",
5985                    30 - level * 3, rdev_get_name(rdev),
5986                    rdev->use_count, rdev->open_count, rdev->bypass_count,
5987                    regulator_opmode_to_str(opmode));
5988
5989         seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
5990         seq_printf(s, "%5dmA ",
5991                    _regulator_get_current_limit_unlocked(rdev) / 1000);
5992
5993         c = rdev->constraints;
5994         if (c) {
5995                 switch (rdev->desc->type) {
5996                 case REGULATOR_VOLTAGE:
5997                         seq_printf(s, "%5dmV %5dmV ",
5998                                    c->min_uV / 1000, c->max_uV / 1000);
5999                         break;
6000                 case REGULATOR_CURRENT:
6001                         seq_printf(s, "%5dmA %5dmA ",
6002                                    c->min_uA / 1000, c->max_uA / 1000);
6003                         break;
6004                 }
6005         }
6006
6007         seq_puts(s, "\n");
6008
6009         list_for_each_entry(consumer, &rdev->consumer_list, list) {
6010                 if (consumer->dev && consumer->dev->class == &regulator_class)
6011                         continue;
6012
6013                 seq_printf(s, "%*s%-*s ",
6014                            (level + 1) * 3 + 1, "",
6015                            30 - (level + 1) * 3,
6016                            consumer->supply_name ? consumer->supply_name :
6017                            consumer->dev ? dev_name(consumer->dev) : "deviceless");
6018
6019                 switch (rdev->desc->type) {
6020                 case REGULATOR_VOLTAGE:
6021                         seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
6022                                    consumer->enable_count,
6023                                    consumer->uA_load / 1000,
6024                                    consumer->uA_load && !consumer->enable_count ?
6025                                    '*' : ' ',
6026                                    consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
6027                                    consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
6028                         break;
6029                 case REGULATOR_CURRENT:
6030                         break;
6031                 }
6032
6033                 seq_puts(s, "\n");
6034         }
6035
6036         summary_data.s = s;
6037         summary_data.level = level;
6038         summary_data.parent = rdev;
6039
6040         class_for_each_device(&regulator_class, NULL, &summary_data,
6041                               regulator_summary_show_children);
6042 }
6043
6044 struct summary_lock_data {
6045         struct ww_acquire_ctx *ww_ctx;
6046         struct regulator_dev **new_contended_rdev;
6047         struct regulator_dev **old_contended_rdev;
6048 };
6049
6050 static int regulator_summary_lock_one(struct device *dev, void *data)
6051 {
6052         struct regulator_dev *rdev = dev_to_rdev(dev);
6053         struct summary_lock_data *lock_data = data;
6054         int ret = 0;
6055
6056         if (rdev != *lock_data->old_contended_rdev) {
6057                 ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
6058
6059                 if (ret == -EDEADLK)
6060                         *lock_data->new_contended_rdev = rdev;
6061                 else
6062                         WARN_ON_ONCE(ret);
6063         } else {
6064                 *lock_data->old_contended_rdev = NULL;
6065         }
6066
6067         return ret;
6068 }
6069
6070 static int regulator_summary_unlock_one(struct device *dev, void *data)
6071 {
6072         struct regulator_dev *rdev = dev_to_rdev(dev);
6073         struct summary_lock_data *lock_data = data;
6074
6075         if (lock_data) {
6076                 if (rdev == *lock_data->new_contended_rdev)
6077                         return -EDEADLK;
6078         }
6079
6080         regulator_unlock(rdev);
6081
6082         return 0;
6083 }
6084
6085 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
6086                                       struct regulator_dev **new_contended_rdev,
6087                                       struct regulator_dev **old_contended_rdev)
6088 {
6089         struct summary_lock_data lock_data;
6090         int ret;
6091
6092         lock_data.ww_ctx = ww_ctx;
6093         lock_data.new_contended_rdev = new_contended_rdev;
6094         lock_data.old_contended_rdev = old_contended_rdev;
6095
6096         ret = class_for_each_device(&regulator_class, NULL, &lock_data,
6097                                     regulator_summary_lock_one);
6098         if (ret)
6099                 class_for_each_device(&regulator_class, NULL, &lock_data,
6100                                       regulator_summary_unlock_one);
6101
6102         return ret;
6103 }
6104
6105 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
6106 {
6107         struct regulator_dev *new_contended_rdev = NULL;
6108         struct regulator_dev *old_contended_rdev = NULL;
6109         int err;
6110
6111         mutex_lock(&regulator_list_mutex);
6112
6113         ww_acquire_init(ww_ctx, &regulator_ww_class);
6114
6115         do {
6116                 if (new_contended_rdev) {
6117                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
6118                         old_contended_rdev = new_contended_rdev;
6119                         old_contended_rdev->ref_cnt++;
6120                         old_contended_rdev->mutex_owner = current;
6121                 }
6122
6123                 err = regulator_summary_lock_all(ww_ctx,
6124                                                  &new_contended_rdev,
6125                                                  &old_contended_rdev);
6126
6127                 if (old_contended_rdev)
6128                         regulator_unlock(old_contended_rdev);
6129
6130         } while (err == -EDEADLK);
6131
6132         ww_acquire_done(ww_ctx);
6133 }
6134
6135 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
6136 {
6137         class_for_each_device(&regulator_class, NULL, NULL,
6138                               regulator_summary_unlock_one);
6139         ww_acquire_fini(ww_ctx);
6140
6141         mutex_unlock(&regulator_list_mutex);
6142 }
6143
6144 static int regulator_summary_show_roots(struct device *dev, void *data)
6145 {
6146         struct regulator_dev *rdev = dev_to_rdev(dev);
6147         struct seq_file *s = data;
6148
6149         if (!rdev->supply)
6150                 regulator_summary_show_subtree(s, rdev, 0);
6151
6152         return 0;
6153 }
6154
6155 static int regulator_summary_show(struct seq_file *s, void *data)
6156 {
6157         struct ww_acquire_ctx ww_ctx;
6158
6159         seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
6160         seq_puts(s, "---------------------------------------------------------------------------------------\n");
6161
6162         regulator_summary_lock(&ww_ctx);
6163
6164         class_for_each_device(&regulator_class, NULL, s,
6165                               regulator_summary_show_roots);
6166
6167         regulator_summary_unlock(&ww_ctx);
6168
6169         return 0;
6170 }
6171 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
6172 #endif /* CONFIG_DEBUG_FS */
6173
6174 static int __init regulator_init(void)
6175 {
6176         int ret;
6177
6178         ret = class_register(&regulator_class);
6179
6180         debugfs_root = debugfs_create_dir("regulator", NULL);
6181         if (!debugfs_root)
6182                 pr_warn("regulator: Failed to create debugfs directory\n");
6183
6184 #ifdef CONFIG_DEBUG_FS
6185         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
6186                             &supply_map_fops);
6187
6188         debugfs_create_file("regulator_summary", 0444, debugfs_root,
6189                             NULL, &regulator_summary_fops);
6190 #endif
6191         regulator_dummy_init();
6192
6193         regulator_coupler_register(&generic_regulator_coupler);
6194
6195         return ret;
6196 }
6197
6198 /* init early to allow our consumers to complete system booting */
6199 core_initcall(regulator_init);
6200
6201 static int regulator_late_cleanup(struct device *dev, void *data)
6202 {
6203         struct regulator_dev *rdev = dev_to_rdev(dev);
6204         struct regulation_constraints *c = rdev->constraints;
6205         int ret;
6206
6207         if (c && c->always_on)
6208                 return 0;
6209
6210         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
6211                 return 0;
6212
6213         regulator_lock(rdev);
6214
6215         if (rdev->use_count)
6216                 goto unlock;
6217
6218         /* If reading the status failed, assume that it's off. */
6219         if (_regulator_is_enabled(rdev) <= 0)
6220                 goto unlock;
6221
6222         if (have_full_constraints()) {
6223                 /* We log since this may kill the system if it goes
6224                  * wrong.
6225                  */
6226                 rdev_info(rdev, "disabling\n");
6227                 ret = _regulator_do_disable(rdev);
6228                 if (ret != 0)
6229                         rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
6230         } else {
6231                 /* The intention is that in future we will
6232                  * assume that full constraints are provided
6233                  * so warn even if we aren't going to do
6234                  * anything here.
6235                  */
6236                 rdev_warn(rdev, "incomplete constraints, leaving on\n");
6237         }
6238
6239 unlock:
6240         regulator_unlock(rdev);
6241
6242         return 0;
6243 }
6244
6245 static void regulator_init_complete_work_function(struct work_struct *work)
6246 {
6247         /*
6248          * Regulators may had failed to resolve their input supplies
6249          * when were registered, either because the input supply was
6250          * not registered yet or because its parent device was not
6251          * bound yet. So attempt to resolve the input supplies for
6252          * pending regulators before trying to disable unused ones.
6253          */
6254         class_for_each_device(&regulator_class, NULL, NULL,
6255                               regulator_register_resolve_supply);
6256
6257         /* If we have a full configuration then disable any regulators
6258          * we have permission to change the status for and which are
6259          * not in use or always_on.  This is effectively the default
6260          * for DT and ACPI as they have full constraints.
6261          */
6262         class_for_each_device(&regulator_class, NULL, NULL,
6263                               regulator_late_cleanup);
6264 }
6265
6266 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
6267                             regulator_init_complete_work_function);
6268
6269 static int __init regulator_init_complete(void)
6270 {
6271         /*
6272          * Since DT doesn't provide an idiomatic mechanism for
6273          * enabling full constraints and since it's much more natural
6274          * with DT to provide them just assume that a DT enabled
6275          * system has full constraints.
6276          */
6277         if (of_have_populated_dt())
6278                 has_full_constraints = true;
6279
6280         /*
6281          * We punt completion for an arbitrary amount of time since
6282          * systems like distros will load many drivers from userspace
6283          * so consumers might not always be ready yet, this is
6284          * particularly an issue with laptops where this might bounce
6285          * the display off then on.  Ideally we'd get a notification
6286          * from userspace when this happens but we don't so just wait
6287          * a bit and hope we waited long enough.  It'd be better if
6288          * we'd only do this on systems that need it, and a kernel
6289          * command line option might be useful.
6290          */
6291         schedule_delayed_work(&regulator_init_complete_work,
6292                               msecs_to_jiffies(30000));
6293
6294         return 0;
6295 }
6296 late_initcall_sync(regulator_init_complete);