drivers/regulator/of_regulator.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * OF helpers for regulator framework
   4  *
   5  * Copyright (C) 2011 Texas Instruments, Inc.
   6  * Rajendra Nayak <[email protected]>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/slab.h>
  11 #include <linux/of.h>
  12 #include <linux/regulator/machine.h>
  13 #include <linux/regulator/driver.h>
  14 #include <linux/regulator/of_regulator.h>
  15
  16 #include "internal.h"
  17
  18 static const char *const regulator_states[PM_SUSPEND_MAX + 1] = {
  19         [PM_SUSPEND_STANDBY]    = "regulator-state-standby",
  20         [PM_SUSPEND_MEM]        = "regulator-state-mem",
  21         [PM_SUSPEND_MAX]        = "regulator-state-disk",
  22 };
  23
  24 static void fill_limit(int *limit, int val)
  25 {
  26         if (val)
  27                 if (val == 1)
  28                         *limit = REGULATOR_NOTIF_LIMIT_ENABLE;
  29                 else
  30                         *limit = val;
  31         else
  32                 *limit = REGULATOR_NOTIF_LIMIT_DISABLE;
  33 }
  34
  35 static void of_get_regulator_prot_limits(struct device_node *np,
  36                                 struct regulation_constraints *constraints)
  37 {
  38         u32 pval;
  39         int i;
  40         static const char *const props[] = {
  41                 "regulator-oc-%s-microamp",
  42                 "regulator-ov-%s-microvolt",
  43                 "regulator-temp-%s-kelvin",
  44                 "regulator-uv-%s-microvolt",
  45         };
  46         struct notification_limit *limits[] = {
  47                 &constraints->over_curr_limits,
  48                 &constraints->over_voltage_limits,
  49                 &constraints->temp_limits,
  50                 &constraints->under_voltage_limits,
  51         };
  52         bool set[4] = {0};
  53
  54         /* Protection limits: */
  55         for (i = 0; i < ARRAY_SIZE(props); i++) {
  56                 char prop[255];
  57                 bool found;
  58                 int j;
  59                 static const char *const lvl[] = {
  60                         "protection", "error", "warn"
  61                 };
  62                 int *l[] = {
  63                         &limits[i]->prot, &limits[i]->err, &limits[i]->warn,
  64                 };
  65
  66                 for (j = 0; j < ARRAY_SIZE(lvl); j++) {
  67                         snprintf(prop, 255, props[i], lvl[j]);
  68                         found = !of_property_read_u32(np, prop, &pval);
  69                         if (found)
  70                                 fill_limit(l[j], pval);
  71                         set[i] |= found;
  72                 }
  73         }
  74         constraints->over_current_detection = set[0];
  75         constraints->over_voltage_detection = set[1];
  76         constraints->over_temp_detection = set[2];
  77         constraints->under_voltage_detection = set[3];
  78 }
  79
  80 static int of_get_regulation_constraints(struct device *dev,
  81                                         struct device_node *np,
  82                                         struct regulator_init_data **init_data,
  83                                         const struct regulator_desc *desc)
  84 {
  85         struct regulation_constraints *constraints = &(*init_data)->constraints;
  86         struct regulator_state *suspend_state;
  87         struct device_node *suspend_np;
  88         unsigned int mode;
  89         int ret, i, len;
  90         int n_phandles;
  91         u32 pval;
  92
  93         n_phandles = of_count_phandle_with_args(np, "regulator-coupled-with",
  94                                                 NULL);
  95         n_phandles = max(n_phandles, 0);
  96
  97         constraints->name = of_get_property(np, "regulator-name", NULL);
  98
  99         if (!of_property_read_u32(np, "regulator-min-microvolt", &pval))
 100                 constraints->min_uV = pval;
 101
 102         if (!of_property_read_u32(np, "regulator-max-microvolt", &pval))
 103                 constraints->max_uV = pval;
 104
 105         /* Voltage change possible? */
 106         if (constraints->min_uV != constraints->max_uV)
 107                 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
 108
 109         /* Do we have a voltage range, if so try to apply it? */
 110         if (constraints->min_uV && constraints->max_uV)
 111                 constraints->apply_uV = true;
 112
 113         if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
 114                 constraints->uV_offset = pval;
 115         if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
 116                 constraints->min_uA = pval;
 117         if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
 118                 constraints->max_uA = pval;
 119
 120         if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
 121                                   &pval))
 122                 constraints->ilim_uA = pval;
 123
 124         /* Current change possible? */
 125         if (constraints->min_uA != constraints->max_uA)
 126                 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
 127
 128         constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
 129         constraints->always_on = of_property_read_bool(np, "regulator-always-on");
 130         if (!constraints->always_on) /* status change should be possible. */
 131                 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
 132
 133         constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");
 134         constraints->system_critical = of_property_read_bool(np,
 135                                                 "system-critical-regulator");
 136
 137         if (of_property_read_bool(np, "regulator-allow-bypass"))
 138                 constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;
 139
 140         if (of_property_read_bool(np, "regulator-allow-set-load"))
 141                 constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;
 142
 143         ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
 144         if (!ret) {
 145                 if (pval)
 146                         constraints->ramp_delay = pval;
 147                 else
 148                         constraints->ramp_disable = true;
 149         }
 150
 151         ret = of_property_read_u32(np, "regulator-settling-time-us", &pval);
 152         if (!ret)
 153                 constraints->settling_time = pval;
 154
 155         ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);
 156         if (!ret)
 157                 constraints->settling_time_up = pval;
 158         if (constraints->settling_time_up && constraints->settling_time) {
 159                 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",
 160                         np);
 161                 constraints->settling_time_up = 0;
 162         }
 163
 164         ret = of_property_read_u32(np, "regulator-settling-time-down-us",
 165                                    &pval);
 166         if (!ret)
 167                 constraints->settling_time_down = pval;
 168         if (constraints->settling_time_down && constraints->settling_time) {
 169                 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",
 170                         np);
 171                 constraints->settling_time_down = 0;
 172         }
 173
 174         ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
 175         if (!ret)
 176                 constraints->enable_time = pval;
 177
 178         ret = of_property_read_u32(np, "regulator-uv-less-critical-window-ms", &pval);
 179         if (!ret)
 180                 constraints->uv_less_critical_window_ms = pval;
 181         else
 182                 constraints->uv_less_critical_window_ms =
 183                                 REGULATOR_DEF_UV_LESS_CRITICAL_WINDOW_MS;
 184
 185         constraints->soft_start = of_property_read_bool(np,
 186                                         "regulator-soft-start");
 187         ret = of_property_read_u32(np, "regulator-active-discharge", &pval);
 188         if (!ret) {
 189                 constraints->active_discharge =
 190                                 (pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :
 191                                         REGULATOR_ACTIVE_DISCHARGE_DISABLE;
 192         }
 193
 194         if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {
 195                 if (desc && desc->of_map_mode) {
 196                         mode = desc->of_map_mode(pval);
 197                         if (mode == REGULATOR_MODE_INVALID)
 198                                 pr_err("%pOFn: invalid mode %u\n", np, pval);
 199                         else
 200                                 constraints->initial_mode = mode;
 201                 } else {
 202                         pr_warn("%pOFn: mapping for mode %d not defined\n",
 203                                 np, pval);
 204                 }
 205         }
 206
 207         len = of_property_count_elems_of_size(np, "regulator-allowed-modes",
 208                                                 sizeof(u32));
 209         if (len > 0) {
 210                 if (desc && desc->of_map_mode) {
 211                         for (i = 0; i < len; i++) {
 212                                 ret = of_property_read_u32_index(np,
 213                                         "regulator-allowed-modes", i, &pval);
 214                                 if (ret) {
 215                                         pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n",
 216                                                 np, i, ret);
 217                                         break;
 218                                 }
 219                                 mode = desc->of_map_mode(pval);
 220                                 if (mode == REGULATOR_MODE_INVALID)
 221                                         pr_err("%pOFn: invalid regulator-allowed-modes element %u\n",
 222                                                 np, pval);
 223                                 else
 224                                         constraints->valid_modes_mask |= mode;
 225                         }
 226                         if (constraints->valid_modes_mask)
 227                                 constraints->valid_ops_mask
 228                                         |= REGULATOR_CHANGE_MODE;
 229                 } else {
 230                         pr_warn("%pOFn: mode mapping not defined\n", np);
 231                 }
 232         }
 233
 234         if (!of_property_read_u32(np, "regulator-system-load", &pval))
 235                 constraints->system_load = pval;
 236
 237         if (n_phandles) {
 238                 constraints->max_spread = devm_kzalloc(dev,
 239                                 sizeof(*constraints->max_spread) * n_phandles,
 240                                 GFP_KERNEL);
 241
 242                 if (!constraints->max_spread)
 243                         return -ENOMEM;
 244
 245                 of_property_read_u32_array(np, "regulator-coupled-max-spread",
 246                                            constraints->max_spread, n_phandles);
 247         }
 248
 249         if (!of_property_read_u32(np, "regulator-max-step-microvolt",
 250                                   &pval))
 251                 constraints->max_uV_step = pval;
 252
 253         constraints->over_current_protection = of_property_read_bool(np,
 254                                         "regulator-over-current-protection");
 255
 256         of_get_regulator_prot_limits(np, constraints);
 257
 258         for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
 259                 switch (i) {
 260                 case PM_SUSPEND_MEM:
 261                         suspend_state = &constraints->state_mem;
 262                         break;
 263                 case PM_SUSPEND_MAX:
 264                         suspend_state = &constraints->state_disk;
 265                         break;
 266                 case PM_SUSPEND_STANDBY:
 267                         suspend_state = &constraints->state_standby;
 268                         break;
 269                 case PM_SUSPEND_ON:
 270                 case PM_SUSPEND_TO_IDLE:
 271                 default:
 272                         continue;
 273                 }
 274
 275                 suspend_np = of_get_child_by_name(np, regulator_states[i]);
 276                 if (!suspend_np)
 277                         continue;
 278                 if (!suspend_state) {
 279                         of_node_put(suspend_np);
 280                         continue;
 281                 }
 282
 283                 if (!of_property_read_u32(suspend_np, "regulator-mode",
 284                                           &pval)) {
 285                         if (desc && desc->of_map_mode) {
 286                                 mode = desc->of_map_mode(pval);
 287                                 if (mode == REGULATOR_MODE_INVALID)
 288                                         pr_err("%pOFn: invalid mode %u\n",
 289                                                np, pval);
 290                                 else
 291                                         suspend_state->mode = mode;
 292                         } else {
 293                                 pr_warn("%pOFn: mapping for mode %d not defined\n",
 294                                         np, pval);
 295                         }
 296                 }
 297
 298                 if (of_property_read_bool(suspend_np,
 299                                         "regulator-on-in-suspend"))
 300                         suspend_state->enabled = ENABLE_IN_SUSPEND;
 301                 else if (of_property_read_bool(suspend_np,
 302                                         "regulator-off-in-suspend"))
 303                         suspend_state->enabled = DISABLE_IN_SUSPEND;
 304
 305                 if (!of_property_read_u32(suspend_np,
 306                                 "regulator-suspend-min-microvolt", &pval))
 307                         suspend_state->min_uV = pval;
 308
 309                 if (!of_property_read_u32(suspend_np,
 310                                 "regulator-suspend-max-microvolt", &pval))
 311                         suspend_state->max_uV = pval;
 312
 313                 if (!of_property_read_u32(suspend_np,
 314                                         "regulator-suspend-microvolt", &pval))
 315                         suspend_state->uV = pval;
 316                 else /* otherwise use min_uV as default suspend voltage */
 317                         suspend_state->uV = suspend_state->min_uV;
 318
 319                 if (of_property_read_bool(suspend_np,
 320                                         "regulator-changeable-in-suspend"))
 321                         suspend_state->changeable = true;
 322
 323                 if (i == PM_SUSPEND_MEM)
 324                         constraints->initial_state = PM_SUSPEND_MEM;
 325
 326                 of_node_put(suspend_np);
 327                 suspend_state = NULL;
 328                 suspend_np = NULL;
 329         }
 330
 331         return 0;
 332 }
 333
 334 /**
 335  * of_get_regulator_init_data - extract regulator_init_data structure info
 336  * @dev: device requesting for regulator_init_data
 337  * @node: regulator device node
 338  * @desc: regulator description
 339  *
 340  * Populates regulator_init_data structure by extracting data from device
 341  * tree node.
 342  *
 343  * Return: Pointer to a populated &struct regulator_init_data or NULL if
 344  *         memory allocation fails.
 345  */
 346 struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
 347                                           struct device_node *node,
 348                                           const struct regulator_desc *desc)
 349 {
 350         struct regulator_init_data *init_data;
 351
 352         if (!node)
 353                 return NULL;
 354
 355         init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
 356         if (!init_data)
 357                 return NULL; /* Out of memory? */
 358
 359         if (of_get_regulation_constraints(dev, node, &init_data, desc))
 360                 return NULL;
 361
 362         return init_data;
 363 }
 364 EXPORT_SYMBOL_GPL(of_get_regulator_init_data);
 365
 366 struct devm_of_regulator_matches {
 367         struct of_regulator_match *matches;
 368         unsigned int num_matches;
 369 };
 370
 371 static void devm_of_regulator_put_matches(struct device *dev, void *res)
 372 {
 373         struct devm_of_regulator_matches *devm_matches = res;
 374         int i;
 375
 376         for (i = 0; i < devm_matches->num_matches; i++)
 377                 of_node_put(devm_matches->matches[i].of_node);
 378 }
 379
 380 /**
 381  * of_regulator_match - extract multiple regulator init data from device tree.
 382  * @dev: device requesting the data
 383  * @node: parent device node of the regulators
 384  * @matches: match table for the regulators
 385  * @num_matches: number of entries in match table
 386  *
 387  * This function uses a match table specified by the regulator driver to
 388  * parse regulator init data from the device tree. @node is expected to
 389  * contain a set of child nodes, each providing the init data for one
 390  * regulator. The data parsed from a child node will be matched to a regulator
 391  * based on either the deprecated property regulator-compatible if present,
 392  * or otherwise the child node's name. Note that the match table is modified
 393  * in place and an additional of_node reference is taken for each matched
 394  * regulator.
 395  *
 396  * Return: The number of matches found or a negative error number on failure.
 397  */
 398 int of_regulator_match(struct device *dev, struct device_node *node,
 399                        struct of_regulator_match *matches,
 400                        unsigned int num_matches)
 401 {
 402         unsigned int count = 0;
 403         unsigned int i;
 404         const char *name;
 405         struct device_node *child;
 406         struct devm_of_regulator_matches *devm_matches;
 407
 408         if (!dev || !node)
 409                 return -EINVAL;
 410
 411         devm_matches = devres_alloc(devm_of_regulator_put_matches,
 412                                     sizeof(struct devm_of_regulator_matches),
 413                                     GFP_KERNEL);
 414         if (!devm_matches)
 415                 return -ENOMEM;
 416
 417         devm_matches->matches = matches;
 418         devm_matches->num_matches = num_matches;
 419
 420         devres_add(dev, devm_matches);
 421
 422         for (i = 0; i < num_matches; i++) {
 423                 struct of_regulator_match *match = &matches[i];
 424                 match->init_data = NULL;
 425                 match->of_node = NULL;
 426         }
 427
 428         for_each_child_of_node(node, child) {
 429                 name = of_get_property(child,
 430                                         "regulator-compatible", NULL);
 431                 if (!name)
 432                         name = child->name;
 433                 for (i = 0; i < num_matches; i++) {
 434                         struct of_regulator_match *match = &matches[i];
 435                         if (match->of_node)
 436                                 continue;
 437
 438                         if (strcmp(match->name, name))
 439                                 continue;
 440
 441                         match->init_data =
 442                                 of_get_regulator_init_data(dev, child,
 443                                                            match->desc);
 444                         if (!match->init_data) {
 445                                 dev_err(dev,
 446                                         "failed to parse DT for regulator %pOFn\n",
 447                                         child);
 448                                 of_node_put(child);
 449                                 return -EINVAL;
 450                         }
 451                         match->of_node = of_node_get(child);
 452                         count++;
 453                         break;
 454                 }
 455         }
 456
 457         return count;
 458 }
 459 EXPORT_SYMBOL_GPL(of_regulator_match);
 460
 461 static struct
 462 device_node *regulator_of_get_init_node(struct device *dev,
 463                                         const struct regulator_desc *desc)
 464 {
 465         struct device_node *search, *child;
 466         const char *name;
 467
 468         if (!dev->of_node || !desc->of_match)
 469                 return NULL;
 470
 471         if (desc->regulators_node) {
 472                 search = of_get_child_by_name(dev->of_node,
 473                                               desc->regulators_node);
 474         } else {
 475                 search = of_node_get(dev->of_node);
 476
 477                 if (!strcmp(desc->of_match, search->name))
 478                         return search;
 479         }
 480
 481         if (!search) {
 482                 dev_dbg(dev, "Failed to find regulator container node '%s'\n",
 483                         desc->regulators_node);
 484                 return NULL;
 485         }
 486
 487         for_each_available_child_of_node(search, child) {
 488                 name = of_get_property(child, "regulator-compatible", NULL);
 489                 if (!name) {
 490                         if (!desc->of_match_full_name)
 491                                 name = child->name;
 492                         else
 493                                 name = child->full_name;
 494                 }
 495
 496                 if (!strcmp(desc->of_match, name)) {
 497                         of_node_put(search);
 498                         /*
 499                          * 'of_node_get(child)' is already performed by the
 500                          * for_each loop.
 501                          */
 502                         return child;
 503                 }
 504         }
 505
 506         of_node_put(search);
 507
 508         return NULL;
 509 }
 510
 511 struct regulator_init_data *regulator_of_get_init_data(struct device *dev,
 512                                             const struct regulator_desc *desc,
 513                                             struct regulator_config *config,
 514                                             struct device_node **node)
 515 {
 516         struct device_node *child;
 517         struct regulator_init_data *init_data = NULL;
 518
 519         child = regulator_of_get_init_node(config->dev, desc);
 520         if (!child)
 521                 return NULL;
 522
 523         init_data = of_get_regulator_init_data(dev, child, desc);
 524         if (!init_data) {
 525                 dev_err(dev, "failed to parse DT for regulator %pOFn\n", child);
 526                 goto error;
 527         }
 528
 529         if (desc->of_parse_cb) {
 530                 int ret;
 531
 532                 ret = desc->of_parse_cb(child, desc, config);
 533                 if (ret) {
 534                         if (ret == -EPROBE_DEFER) {
 535                                 of_node_put(child);
 536                                 return ERR_PTR(-EPROBE_DEFER);
 537                         }
 538                         dev_err(dev,
 539                                 "driver callback failed to parse DT for regulator %pOFn\n",
 540                                 child);
 541                         goto error;
 542                 }
 543         }
 544
 545         *node = child;
 546
 547         return init_data;
 548
 549 error:
 550         of_node_put(child);
 551
 552         return NULL;
 553 }
 554
 555 /**
 556  * of_get_child_regulator - get a child regulator device node
 557  * based on supply name
 558  * @parent: Parent device node
 559  * @prop_name: Combination regulator supply name and "-supply"
 560  *
 561  * Traverse all child nodes.
 562  * Extract the child regulator device node corresponding to the supply name.
 563  *
 564  * Return: Pointer to the &struct device_node corresponding to the regulator
 565  *         if found, or %NULL if not found.
 566  */
 567 static struct device_node *of_get_child_regulator(struct device_node *parent,
 568                                                   const char *prop_name)
 569 {
 570         struct device_node *regnode = NULL;
 571         struct device_node *child = NULL;
 572
 573         for_each_child_of_node(parent, child) {
 574                 regnode = of_parse_phandle(child, prop_name, 0);
 575                 if (regnode)
 576                         goto err_node_put;
 577
 578                 regnode = of_get_child_regulator(child, prop_name);
 579                 if (regnode)
 580                         goto err_node_put;
 581         }
 582         return NULL;
 583
 584 err_node_put:
 585         of_node_put(child);
 586         return regnode;
 587 }
 588
 589 /**
 590  * of_get_regulator - get a regulator device node based on supply name
 591  * @dev: Device pointer for dev_printk() messages
 592  * @node: Device node pointer for supply property lookup
 593  * @supply: regulator supply name
 594  *
 595  * Extract the regulator device node corresponding to the supply name.
 596  *
 597  * Return: Pointer to the &struct device_node corresponding to the regulator
 598  *         if found, or %NULL if not found.
 599  */
 600 static struct device_node *of_get_regulator(struct device *dev, struct device_node *node,
 601                                             const char *supply)
 602 {
 603         struct device_node *regnode = NULL;
 604         char prop_name[64]; /* 64 is max size of property name */
 605
 606         dev_dbg(dev, "Looking up %s-supply from device node %pOF\n", supply, node);
 607
 608         snprintf(prop_name, 64, "%s-supply", supply);
 609         regnode = of_parse_phandle(node, prop_name, 0);
 610         if (regnode)
 611                 return regnode;
 612
 613         regnode = of_get_child_regulator(dev->of_node, prop_name);
 614         if (regnode)
 615                 return regnode;
 616
 617         dev_dbg(dev, "Looking up %s property in node %pOF failed\n", prop_name, dev->of_node);
 618         return NULL;
 619 }
 620
 621 static struct regulator_dev *of_find_regulator_by_node(struct device_node *np)
 622 {
 623         struct device *dev;
 624
 625         dev = class_find_device_by_of_node(&regulator_class, np);
 626
 627         return dev ? dev_to_rdev(dev) : NULL;
 628 }
 629
 630 /**
 631  * of_regulator_dev_lookup - lookup a regulator device with device tree only
 632  * @dev: Device pointer for regulator supply lookup.
 633  * @np: Device node pointer for regulator supply lookup.
 634  * @supply: Supply name or regulator ID.
 635  *
 636  * Return: Pointer to the &struct regulator_dev on success, or ERR_PTR()
 637  *         encoded value on error.
 638  *
 639  * If successful, returns a pointer to the &struct regulator_dev that
 640  * corresponds to the name @supply and with the embedded &struct device
 641  * refcount incremented by one. The refcount must be dropped by calling
 642  * put_device().
 643  *
 644  * On failure one of the following ERR_PTR() encoded values is returned:
 645  * * -%ENODEV if lookup fails permanently.
 646  * * -%EPROBE_DEFER if lookup could succeed in the future.
 647  */
 648 struct regulator_dev *of_regulator_dev_lookup(struct device *dev, struct device_node *np,
 649                                               const char *supply)
 650 {
 651         struct regulator_dev *r;
 652         struct device_node *node;
 653
 654         node = of_get_regulator(dev, np, supply);
 655         if (node) {
 656                 r = of_find_regulator_by_node(node);
 657                 of_node_put(node);
 658                 if (r)
 659                         return r;
 660
 661                 /*
 662                  * We have a node, but there is no device.
 663                  * assume it has not registered yet.
 664                  */
 665                 return ERR_PTR(-EPROBE_DEFER);
 666         }
 667
 668         return ERR_PTR(-ENODEV);
 669 }
 670
 671 struct regulator *_of_regulator_get(struct device *dev, struct device_node *node,
 672                                     const char *id, enum regulator_get_type get_type)
 673 {
 674         struct regulator_dev *r;
 675         int ret;
 676
 677         ret = _regulator_get_common_check(dev, id, get_type);
 678         if (ret)
 679                 return ERR_PTR(ret);
 680
 681         r = of_regulator_dev_lookup(dev, node, id);
 682         return _regulator_get_common(r, dev, id, get_type);
 683 }
 684
 685 /**
 686  * of_regulator_get_optional - get optional regulator via device tree lookup
 687  * @dev: device used for dev_printk() messages
 688  * @node: device node for regulator "consumer"
 689  * @id: Supply name
 690  *
 691  * Return: pointer to struct regulator corresponding to the regulator producer,
 692  *         or PTR_ERR() encoded error number.
 693  *
 694  * This is intended for use by consumers that want to get a regulator
 695  * supply directly from a device node, and can and want to deal with
 696  * absence of such supplies. This will _not_ consider supply aliases.
 697  * See regulator_dev_lookup().
 698  */
 699 struct regulator *of_regulator_get_optional(struct device *dev,
 700                                             struct device_node *node,
 701                                             const char *id)
 702 {
 703         return _of_regulator_get(dev, node, id, OPTIONAL_GET);
 704 }
 705 EXPORT_SYMBOL_GPL(of_regulator_get_optional);
 706
 707 /*
 708  * Returns number of regulators coupled with rdev.
 709  */
 710 int of_get_n_coupled(struct regulator_dev *rdev)
 711 {
 712         struct device_node *node = rdev->dev.of_node;
 713         int n_phandles;
 714
 715         n_phandles = of_count_phandle_with_args(node,
 716                                                 "regulator-coupled-with",
 717                                                 NULL);
 718
 719         return (n_phandles > 0) ? n_phandles : 0;
 720 }
 721
 722 /* Looks for "to_find" device_node in src's "regulator-coupled-with" property */
 723 static bool of_coupling_find_node(struct device_node *src,
 724                                   struct device_node *to_find,
 725                                   int *index)
 726 {
 727         int n_phandles, i;
 728         bool found = false;
 729
 730         n_phandles = of_count_phandle_with_args(src,
 731                                                 "regulator-coupled-with",
 732                                                 NULL);
 733
 734         for (i = 0; i < n_phandles; i++) {
 735                 struct device_node *tmp = of_parse_phandle(src,
 736                                            "regulator-coupled-with", i);
 737
 738                 if (!tmp)
 739                         break;
 740
 741                 /* found */
 742                 if (tmp == to_find)
 743                         found = true;
 744
 745                 of_node_put(tmp);
 746
 747                 if (found) {
 748                         *index = i;
 749                         break;
 750                 }
 751         }
 752
 753         return found;
 754 }
 755
 756 /**
 757  * of_check_coupling_data - Parse rdev's coupling properties and check data
 758  *                          consistency
 759  * @rdev: pointer to regulator_dev whose data is checked
 760  *
 761  * Function checks if all the following conditions are met:
 762  * - rdev's max_spread is greater than 0
 763  * - all coupled regulators have the same max_spread
 764  * - all coupled regulators have the same number of regulator_dev phandles
 765  * - all regulators are linked to each other
 766  *
 767  * Return: True if all conditions are met; false otherwise.
 768  */
 769 bool of_check_coupling_data(struct regulator_dev *rdev)
 770 {
 771         struct device_node *node = rdev->dev.of_node;
 772         int n_phandles = of_get_n_coupled(rdev);
 773         struct device_node *c_node;
 774         int index;
 775         int i;
 776         bool ret = true;
 777
 778         /* iterate over rdev's phandles */
 779         for (i = 0; i < n_phandles; i++) {
 780                 int max_spread = rdev->constraints->max_spread[i];
 781                 int c_max_spread, c_n_phandles;
 782
 783                 if (max_spread <= 0) {
 784                         dev_err(&rdev->dev, "max_spread value invalid\n");
 785                         return false;
 786                 }
 787
 788                 c_node = of_parse_phandle(node,
 789                                           "regulator-coupled-with", i);
 790
 791                 if (!c_node)
 792                         ret = false;
 793
 794                 c_n_phandles = of_count_phandle_with_args(c_node,
 795                                                           "regulator-coupled-with",
 796                                                           NULL);
 797
 798                 if (c_n_phandles != n_phandles) {
 799                         dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n");
 800                         ret = false;
 801                         goto clean;
 802                 }
 803
 804                 if (!of_coupling_find_node(c_node, node, &index)) {
 805                         dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");
 806                         ret = false;
 807                         goto clean;
 808                 }
 809
 810                 if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",
 811                                                index, &c_max_spread)) {
 812                         ret = false;
 813                         goto clean;
 814                 }
 815
 816                 if (c_max_spread != max_spread) {
 817                         dev_err(&rdev->dev,
 818                                 "coupled regulators max_spread mismatch\n");
 819                         ret = false;
 820                         goto clean;
 821                 }
 822
 823 clean:
 824                 of_node_put(c_node);
 825                 if (!ret)
 826                         break;
 827         }
 828
 829         return ret;
 830 }
 831
 832 /**
 833  * of_parse_coupled_regulator() - Get regulator_dev pointer from rdev's property
 834  * @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse
 835  *        "regulator-coupled-with" property
 836  * @index: Index in phandles array
 837  *
 838  * Return: Pointer to the &struct regulator_dev parsed from DTS, or %NULL if
 839  *         it has not yet been registered.
 840  */
 841 struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev,
 842                                                  int index)
 843 {
 844         struct device_node *node = rdev->dev.of_node;
 845         struct device_node *c_node;
 846         struct regulator_dev *c_rdev;
 847
 848         c_node = of_parse_phandle(node, "regulator-coupled-with", index);
 849         if (!c_node)
 850                 return NULL;
 851
 852         c_rdev = of_find_regulator_by_node(c_node);
 853
 854         of_node_put(c_node);
 855
 856         return c_rdev;
 857 }
 858
 859 /*
 860  * Check if name is a supply name according to the '*-supply' pattern
 861  * return 0 if false
 862  * return length of supply name without the -supply
 863  */
 864 static int is_supply_name(const char *name)
 865 {
 866         int strs, i;
 867
 868         strs = strlen(name);
 869         /* string need to be at minimum len(x-supply) */
 870         if (strs < 8)
 871                 return 0;
 872         for (i = strs - 6; i > 0; i--) {
 873                 /* find first '-' and check if right part is supply */
 874                 if (name[i] != '-')
 875                         continue;
 876                 if (strcmp(name + i + 1, "supply") != 0)
 877                         return 0;
 878                 return i;
 879         }
 880         return 0;
 881 }
 882
 883 /**
 884  * of_regulator_bulk_get_all - get multiple regulator consumers
 885  *
 886  * @dev:        Device to supply
 887  * @np:         device node to search for consumers
 888  * @consumers:  Configuration of consumers; clients are stored here.
 889  *
 890  * This helper function allows drivers to get several regulator
 891  * consumers in one operation.  If any of the regulators cannot be
 892  * acquired then any regulators that were allocated will be freed
 893  * before returning to the caller, and @consumers will not be
 894  * changed.
 895  *
 896  * Return: Number of regulators on success, or a negative error number
 897  *         on failure.
 898  */
 899 int of_regulator_bulk_get_all(struct device *dev, struct device_node *np,
 900                               struct regulator_bulk_data **consumers)
 901 {
 902         int num_consumers = 0;
 903         struct regulator *tmp;
 904         struct regulator_bulk_data *_consumers = NULL;
 905         struct property *prop;
 906         int i, n = 0, ret;
 907         char name[64];
 908
 909         /*
 910          * first pass: get numbers of xxx-supply
 911          * second pass: fill consumers
 912          */
 913 restart:
 914         for_each_property_of_node(np, prop) {
 915                 i = is_supply_name(prop->name);
 916                 if (i == 0)
 917                         continue;
 918                 if (!_consumers) {
 919                         num_consumers++;
 920                         continue;
 921                 } else {
 922                         memcpy(name, prop->name, i);
 923                         name[i] = '\0';
 924                         tmp = regulator_get(dev, name);
 925                         if (IS_ERR(tmp)) {
 926                                 ret = PTR_ERR(tmp);
 927                                 goto error;
 928                         }
 929                         _consumers[n].consumer = tmp;
 930                         n++;
 931                         continue;
 932                 }
 933         }
 934         if (_consumers) {
 935                 *consumers = _consumers;
 936                 return num_consumers;
 937         }
 938         if (num_consumers == 0)
 939                 return 0;
 940         _consumers = kmalloc_array(num_consumers,
 941                                    sizeof(struct regulator_bulk_data),
 942                                    GFP_KERNEL);
 943         if (!_consumers)
 944                 return -ENOMEM;
 945         goto restart;
 946
 947 error:
 948         while (--n >= 0)
 949                 regulator_put(_consumers[n].consumer);
 950         kfree(_consumers);
 951         return ret;
 952 }
 953 EXPORT_SYMBOL_GPL(of_regulator_bulk_get_all);