drivers/base/power/domain.c

   1 /*
   2  * drivers/base/power/domain.c - Common code related to device power domains.
   3  *
   4  * Copyright (C) 2011 Rafael J. Wysocki <[email protected]>, Renesas Electronics Corp.
   5  *
   6  * This file is released under the GPLv2.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/io.h>
  12 #include <linux/pm_runtime.h>
  13 #include <linux/pm_domain.h>
  14 #include <linux/pm_qos.h>
  15 #include <linux/slab.h>
  16 #include <linux/err.h>
  17 #include <linux/sched.h>
  18 #include <linux/suspend.h>
  19 #include <linux/export.h>
  20
  21 #define GENPD_DEV_CALLBACK(genpd, type, callback, dev)          \
  22 ({                                                              \
  23         type (*__routine)(struct device *__d);                  \
  24         type __ret = (type)0;                                   \
  25                                                                 \
  26         __routine = genpd->dev_ops.callback;                    \
  27         if (__routine) {                                        \
  28                 __ret = __routine(dev);                         \
  29         } else {                                                \
  30                 __routine = dev_gpd_data(dev)->ops.callback;    \
  31                 if (__routine)                                  \
  32                         __ret = __routine(dev);                 \
  33         }                                                       \
  34         __ret;                                                  \
  35 })
  36
  37 #define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name)       \
  38 ({                                                                              \
  39         ktime_t __start = ktime_get();                                          \
  40         type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev);         \
  41         s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start));           \
  42         struct gpd_timing_data *__td = &dev_gpd_data(dev)->td;                  \
  43         if (!__retval && __elapsed > __td->field) {                             \
  44                 __td->field = __elapsed;                                        \
  45                 dev_warn(dev, name " latency exceeded, new value %lld ns\n",    \
  46                         __elapsed);                                             \
  47                 genpd->max_off_time_changed = true;                             \
  48                 __td->constraint_changed = true;                                \
  49         }                                                                       \
  50         __retval;                                                               \
  51 })
  52
  53 static LIST_HEAD(gpd_list);
  54 static DEFINE_MUTEX(gpd_list_lock);
  55
  56 static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
  57 {
  58         struct generic_pm_domain *genpd = NULL, *gpd;
  59
  60         if (IS_ERR_OR_NULL(domain_name))
  61                 return NULL;
  62
  63         mutex_lock(&gpd_list_lock);
  64         list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
  65                 if (!strcmp(gpd->name, domain_name)) {
  66                         genpd = gpd;
  67                         break;
  68                 }
  69         }
  70         mutex_unlock(&gpd_list_lock);
  71         return genpd;
  72 }
  73
  74 #ifdef CONFIG_PM
  75
  76 struct generic_pm_domain *dev_to_genpd(struct device *dev)
  77 {
  78         if (IS_ERR_OR_NULL(dev->pm_domain))
  79                 return ERR_PTR(-EINVAL);
  80
  81         return pd_to_genpd(dev->pm_domain);
  82 }
  83
  84 static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
  85 {
  86         return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
  87                                         stop_latency_ns, "stop");
  88 }
  89
  90 static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
  91 {
  92         return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
  93                                         start_latency_ns, "start");
  94 }
  95
  96 static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
  97 {
  98         bool ret = false;
  99
 100         if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
 101                 ret = !!atomic_dec_and_test(&genpd->sd_count);
 102
 103         return ret;
 104 }
 105
 106 static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 107 {
 108         atomic_inc(&genpd->sd_count);
 109         smp_mb__after_atomic_inc();
 110 }
 111
 112 static void genpd_acquire_lock(struct generic_pm_domain *genpd)
 113 {
 114         DEFINE_WAIT(wait);
 115
 116         mutex_lock(&genpd->lock);
 117         /*
 118          * Wait for the domain to transition into either the active,
 119          * or the power off state.
 120          */
 121         for (;;) {
 122                 prepare_to_wait(&genpd->status_wait_queue, &wait,
 123                                 TASK_UNINTERRUPTIBLE);
 124                 if (genpd->status == GPD_STATE_ACTIVE
 125                     || genpd->status == GPD_STATE_POWER_OFF)
 126                         break;
 127                 mutex_unlock(&genpd->lock);
 128
 129                 schedule();
 130
 131                 mutex_lock(&genpd->lock);
 132         }
 133         finish_wait(&genpd->status_wait_queue, &wait);
 134 }
 135
 136 static void genpd_release_lock(struct generic_pm_domain *genpd)
 137 {
 138         mutex_unlock(&genpd->lock);
 139 }
 140
 141 static void genpd_set_active(struct generic_pm_domain *genpd)
 142 {
 143         if (genpd->resume_count == 0)
 144                 genpd->status = GPD_STATE_ACTIVE;
 145 }
 146
 147 static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
 148 {
 149         s64 usecs64;
 150
 151         if (!genpd->cpu_data)
 152                 return;
 153
 154         usecs64 = genpd->power_on_latency_ns;
 155         do_div(usecs64, NSEC_PER_USEC);
 156         usecs64 += genpd->cpu_data->saved_exit_latency;
 157         genpd->cpu_data->idle_state->exit_latency = usecs64;
 158 }
 159
 160 /**
 161  * __pm_genpd_poweron - Restore power to a given PM domain and its masters.
 162  * @genpd: PM domain to power up.
 163  *
 164  * Restore power to @genpd and all of its masters so that it is possible to
 165  * resume a device belonging to it.
 166  */
 167 static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
 168         __releases(&genpd->lock) __acquires(&genpd->lock)
 169 {
 170         struct gpd_link *link;
 171         DEFINE_WAIT(wait);
 172         int ret = 0;
 173
 174         /* If the domain's master is being waited for, we have to wait too. */
 175         for (;;) {
 176                 prepare_to_wait(&genpd->status_wait_queue, &wait,
 177                                 TASK_UNINTERRUPTIBLE);
 178                 if (genpd->status != GPD_STATE_WAIT_MASTER)
 179                         break;
 180                 mutex_unlock(&genpd->lock);
 181
 182                 schedule();
 183
 184                 mutex_lock(&genpd->lock);
 185         }
 186         finish_wait(&genpd->status_wait_queue, &wait);
 187
 188         if (genpd->status == GPD_STATE_ACTIVE
 189             || (genpd->prepared_count > 0 && genpd->suspend_power_off))
 190                 return 0;
 191
 192         if (genpd->status != GPD_STATE_POWER_OFF) {
 193                 genpd_set_active(genpd);
 194                 return 0;
 195         }
 196
 197         if (genpd->cpu_data) {
 198                 cpuidle_pause_and_lock();
 199                 genpd->cpu_data->idle_state->disabled = true;
 200                 cpuidle_resume_and_unlock();
 201                 goto out;
 202         }
 203
 204         /*
 205          * The list is guaranteed not to change while the loop below is being
 206          * executed, unless one of the masters' .power_on() callbacks fiddles
 207          * with it.
 208          */
 209         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 210                 genpd_sd_counter_inc(link->master);
 211                 genpd->status = GPD_STATE_WAIT_MASTER;
 212
 213                 mutex_unlock(&genpd->lock);
 214
 215                 ret = pm_genpd_poweron(link->master);
 216
 217                 mutex_lock(&genpd->lock);
 218
 219                 /*
 220                  * The "wait for parent" status is guaranteed not to change
 221                  * while the master is powering on.
 222                  */
 223                 genpd->status = GPD_STATE_POWER_OFF;
 224                 wake_up_all(&genpd->status_wait_queue);
 225                 if (ret) {
 226                         genpd_sd_counter_dec(link->master);
 227                         goto err;
 228                 }
 229         }
 230
 231         if (genpd->power_on) {
 232                 ktime_t time_start = ktime_get();
 233                 s64 elapsed_ns;
 234
 235                 ret = genpd->power_on(genpd);
 236                 if (ret)
 237                         goto err;
 238
 239                 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 240                 if (elapsed_ns > genpd->power_on_latency_ns) {
 241                         genpd->power_on_latency_ns = elapsed_ns;
 242                         genpd->max_off_time_changed = true;
 243                         genpd_recalc_cpu_exit_latency(genpd);
 244                         if (genpd->name)
 245                                 pr_warning("%s: Power-on latency exceeded, "
 246                                         "new value %lld ns\n", genpd->name,
 247                                         elapsed_ns);
 248                 }
 249         }
 250
 251  out:
 252         genpd_set_active(genpd);
 253
 254         return 0;
 255
 256  err:
 257         list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
 258                 genpd_sd_counter_dec(link->master);
 259
 260         return ret;
 261 }
 262
 263 /**
 264  * pm_genpd_poweron - Restore power to a given PM domain and its masters.
 265  * @genpd: PM domain to power up.
 266  */
 267 int pm_genpd_poweron(struct generic_pm_domain *genpd)
 268 {
 269         int ret;
 270
 271         mutex_lock(&genpd->lock);
 272         ret = __pm_genpd_poweron(genpd);
 273         mutex_unlock(&genpd->lock);
 274         return ret;
 275 }
 276
 277 /**
 278  * pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
 279  * @domain_name: Name of the PM domain to power up.
 280  */
 281 int pm_genpd_name_poweron(const char *domain_name)
 282 {
 283         struct generic_pm_domain *genpd;
 284
 285         genpd = pm_genpd_lookup_name(domain_name);
 286         return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
 287 }
 288
 289 #endif /* CONFIG_PM */
 290
 291 #ifdef CONFIG_PM_RUNTIME
 292
 293 static int genpd_start_dev_no_timing(struct generic_pm_domain *genpd,
 294                                      struct device *dev)
 295 {
 296         return GENPD_DEV_CALLBACK(genpd, int, start, dev);
 297 }
 298
 299 static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
 300 {
 301         return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
 302                                         save_state_latency_ns, "state save");
 303 }
 304
 305 static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev)
 306 {
 307         return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
 308                                         restore_state_latency_ns,
 309                                         "state restore");
 310 }
 311
 312 static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 313                                      unsigned long val, void *ptr)
 314 {
 315         struct generic_pm_domain_data *gpd_data;
 316         struct device *dev;
 317
 318         gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
 319
 320         mutex_lock(&gpd_data->lock);
 321         dev = gpd_data->base.dev;
 322         if (!dev) {
 323                 mutex_unlock(&gpd_data->lock);
 324                 return NOTIFY_DONE;
 325         }
 326         mutex_unlock(&gpd_data->lock);
 327
 328         for (;;) {
 329                 struct generic_pm_domain *genpd;
 330                 struct pm_domain_data *pdd;
 331
 332                 spin_lock_irq(&dev->power.lock);
 333
 334                 pdd = dev->power.subsys_data ?
 335                                 dev->power.subsys_data->domain_data : NULL;
 336                 if (pdd && pdd->dev) {
 337                         to_gpd_data(pdd)->td.constraint_changed = true;
 338                         genpd = dev_to_genpd(dev);
 339                 } else {
 340                         genpd = ERR_PTR(-ENODATA);
 341                 }
 342
 343                 spin_unlock_irq(&dev->power.lock);
 344
 345                 if (!IS_ERR(genpd)) {
 346                         mutex_lock(&genpd->lock);
 347                         genpd->max_off_time_changed = true;
 348                         mutex_unlock(&genpd->lock);
 349                 }
 350
 351                 dev = dev->parent;
 352                 if (!dev || dev->power.ignore_children)
 353                         break;
 354         }
 355
 356         return NOTIFY_DONE;
 357 }
 358
 359 /**
 360  * __pm_genpd_save_device - Save the pre-suspend state of a device.
 361  * @pdd: Domain data of the device to save the state of.
 362  * @genpd: PM domain the device belongs to.
 363  */
 364 static int __pm_genpd_save_device(struct pm_domain_data *pdd,
 365                                   struct generic_pm_domain *genpd)
 366         __releases(&genpd->lock) __acquires(&genpd->lock)
 367 {
 368         struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
 369         struct device *dev = pdd->dev;
 370         int ret = 0;
 371
 372         if (gpd_data->need_restore)
 373                 return 0;
 374
 375         mutex_unlock(&genpd->lock);
 376
 377         genpd_start_dev(genpd, dev);
 378         ret = genpd_save_dev(genpd, dev);
 379         genpd_stop_dev(genpd, dev);
 380
 381         mutex_lock(&genpd->lock);
 382
 383         if (!ret)
 384                 gpd_data->need_restore = true;
 385
 386         return ret;
 387 }
 388
 389 /**
 390  * __pm_genpd_restore_device - Restore the pre-suspend state of a device.
 391  * @pdd: Domain data of the device to restore the state of.
 392  * @genpd: PM domain the device belongs to.
 393  */
 394 static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
 395                                       struct generic_pm_domain *genpd)
 396         __releases(&genpd->lock) __acquires(&genpd->lock)
 397 {
 398         struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
 399         struct device *dev = pdd->dev;
 400         bool need_restore = gpd_data->need_restore;
 401
 402         gpd_data->need_restore = false;
 403         mutex_unlock(&genpd->lock);
 404
 405         genpd_start_dev(genpd, dev);
 406         if (need_restore)
 407                 genpd_restore_dev(genpd, dev);
 408
 409         mutex_lock(&genpd->lock);
 410 }
 411
 412 /**
 413  * genpd_abort_poweroff - Check if a PM domain power off should be aborted.
 414  * @genpd: PM domain to check.
 415  *
 416  * Return true if a PM domain's status changed to GPD_STATE_ACTIVE during
 417  * a "power off" operation, which means that a "power on" has occured in the
 418  * meantime, or if its resume_count field is different from zero, which means
 419  * that one of its devices has been resumed in the meantime.
 420  */
 421 static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
 422 {
 423         return genpd->status == GPD_STATE_WAIT_MASTER
 424                 || genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
 425 }
 426
 427 /**
 428  * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
 429  * @genpd: PM domait to power off.
 430  *
 431  * Queue up the execution of pm_genpd_poweroff() unless it's already been done
 432  * before.
 433  */
 434 void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 435 {
 436         queue_work(pm_wq, &genpd->power_off_work);
 437 }
 438
 439 /**
 440  * pm_genpd_poweroff - Remove power from a given PM domain.
 441  * @genpd: PM domain to power down.
 442  *
 443  * If all of the @genpd's devices have been suspended and all of its subdomains
 444  * have been powered down, run the runtime suspend callbacks provided by all of
 445  * the @genpd's devices' drivers and remove power from @genpd.
 446  */
 447 static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
 448         __releases(&genpd->lock) __acquires(&genpd->lock)
 449 {
 450         struct pm_domain_data *pdd;
 451         struct gpd_link *link;
 452         unsigned int not_suspended;
 453         int ret = 0;
 454
 455  start:
 456         /*
 457          * Do not try to power off the domain in the following situations:
 458          * (1) The domain is already in the "power off" state.
 459          * (2) The domain is waiting for its master to power up.
 460          * (3) One of the domain's devices is being resumed right now.
 461          * (4) System suspend is in progress.
 462          */
 463         if (genpd->status == GPD_STATE_POWER_OFF
 464             || genpd->status == GPD_STATE_WAIT_MASTER
 465             || genpd->resume_count > 0 || genpd->prepared_count > 0)
 466                 return 0;
 467
 468         if (atomic_read(&genpd->sd_count) > 0)
 469                 return -EBUSY;
 470
 471         not_suspended = 0;
 472         list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 473                 enum pm_qos_flags_status stat;
 474
 475                 stat = dev_pm_qos_flags(pdd->dev,
 476                                         PM_QOS_FLAG_NO_POWER_OFF
 477                                                 | PM_QOS_FLAG_REMOTE_WAKEUP);
 478                 if (stat > PM_QOS_FLAGS_NONE)
 479                         return -EBUSY;
 480
 481                 if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
 482                     || pdd->dev->power.irq_safe))
 483                         not_suspended++;
 484         }
 485
 486         if (not_suspended > genpd->in_progress)
 487                 return -EBUSY;
 488
 489         if (genpd->poweroff_task) {
 490                 /*
 491                  * Another instance of pm_genpd_poweroff() is executing
 492                  * callbacks, so tell it to start over and return.
 493                  */
 494                 genpd->status = GPD_STATE_REPEAT;
 495                 return 0;
 496         }
 497
 498         if (genpd->gov && genpd->gov->power_down_ok) {
 499                 if (!genpd->gov->power_down_ok(&genpd->domain))
 500                         return -EAGAIN;
 501         }
 502
 503         genpd->status = GPD_STATE_BUSY;
 504         genpd->poweroff_task = current;
 505
 506         list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
 507                 ret = atomic_read(&genpd->sd_count) == 0 ?
 508                         __pm_genpd_save_device(pdd, genpd) : -EBUSY;
 509
 510                 if (genpd_abort_poweroff(genpd))
 511                         goto out;
 512
 513                 if (ret) {
 514                         genpd_set_active(genpd);
 515                         goto out;
 516                 }
 517
 518                 if (genpd->status == GPD_STATE_REPEAT) {
 519                         genpd->poweroff_task = NULL;
 520                         goto start;
 521                 }
 522         }
 523
 524         if (genpd->cpu_data) {
 525                 /*
 526                  * If cpu_data is set, cpuidle should turn the domain off when
 527                  * the CPU in it is idle.  In that case we don't decrement the
 528                  * subdomain counts of the master domains, so that power is not
 529                  * removed from the current domain prematurely as a result of
 530                  * cutting off the masters' power.
 531                  */
 532                 genpd->status = GPD_STATE_POWER_OFF;
 533                 cpuidle_pause_and_lock();
 534                 genpd->cpu_data->idle_state->disabled = false;
 535                 cpuidle_resume_and_unlock();
 536                 goto out;
 537         }
 538
 539         if (genpd->power_off) {
 540                 ktime_t time_start;
 541                 s64 elapsed_ns;
 542
 543                 if (atomic_read(&genpd->sd_count) > 0) {
 544                         ret = -EBUSY;
 545                         goto out;
 546                 }
 547
 548                 time_start = ktime_get();
 549
 550                 /*
 551                  * If sd_count > 0 at this point, one of the subdomains hasn't
 552                  * managed to call pm_genpd_poweron() for the master yet after
 553                  * incrementing it.  In that case pm_genpd_poweron() will wait
 554                  * for us to drop the lock, so we can call .power_off() and let
 555                  * the pm_genpd_poweron() restore power for us (this shouldn't
 556                  * happen very often).
 557                  */
 558                 ret = genpd->power_off(genpd);
 559                 if (ret == -EBUSY) {
 560                         genpd_set_active(genpd);
 561                         goto out;
 562                 }
 563
 564                 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 565                 if (elapsed_ns > genpd->power_off_latency_ns) {
 566                         genpd->power_off_latency_ns = elapsed_ns;
 567                         genpd->max_off_time_changed = true;
 568                         if (genpd->name)
 569                                 pr_warning("%s: Power-off latency exceeded, "
 570                                         "new value %lld ns\n", genpd->name,
 571                                         elapsed_ns);
 572                 }
 573         }
 574
 575         genpd->status = GPD_STATE_POWER_OFF;
 576
 577         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 578                 genpd_sd_counter_dec(link->master);
 579                 genpd_queue_power_off_work(link->master);
 580         }
 581
 582  out:
 583         genpd->poweroff_task = NULL;
 584         wake_up_all(&genpd->status_wait_queue);
 585         return ret;
 586 }
 587
 588 /**
 589  * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 590  * @work: Work structure used for scheduling the execution of this function.
 591  */
 592 static void genpd_power_off_work_fn(struct work_struct *work)
 593 {
 594         struct generic_pm_domain *genpd;
 595
 596         genpd = container_of(work, struct generic_pm_domain, power_off_work);
 597
 598         genpd_acquire_lock(genpd);
 599         pm_genpd_poweroff(genpd);
 600         genpd_release_lock(genpd);
 601 }
 602
 603 /**
 604  * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 605  * @dev: Device to suspend.
 606  *
 607  * Carry out a runtime suspend of a device under the assumption that its
 608  * pm_domain field points to the domain member of an object of type
 609  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 610  */
 611 static int pm_genpd_runtime_suspend(struct device *dev)
 612 {
 613         struct generic_pm_domain *genpd;
 614         bool (*stop_ok)(struct device *__dev);
 615         int ret;
 616
 617         dev_dbg(dev, "%s()\n", __func__);
 618
 619         genpd = dev_to_genpd(dev);
 620         if (IS_ERR(genpd))
 621                 return -EINVAL;
 622
 623         might_sleep_if(!genpd->dev_irq_safe);
 624
 625         stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
 626         if (stop_ok && !stop_ok(dev))
 627                 return -EBUSY;
 628
 629         ret = genpd_stop_dev(genpd, dev);
 630         if (ret)
 631                 return ret;
 632
 633         /*
 634          * If power.irq_safe is set, this routine will be run with interrupts
 635          * off, so it can't use mutexes.
 636          */
 637         if (dev->power.irq_safe)
 638                 return 0;
 639
 640         mutex_lock(&genpd->lock);
 641         genpd->in_progress++;
 642         pm_genpd_poweroff(genpd);
 643         genpd->in_progress--;
 644         mutex_unlock(&genpd->lock);
 645
 646         return 0;
 647 }
 648
 649 /**
 650  * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
 651  * @dev: Device to resume.
 652  *
 653  * Carry out a runtime resume of a device under the assumption that its
 654  * pm_domain field points to the domain member of an object of type
 655  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 656  */
 657 static int pm_genpd_runtime_resume(struct device *dev)
 658 {
 659         struct generic_pm_domain *genpd;
 660         DEFINE_WAIT(wait);
 661         int ret;
 662
 663         dev_dbg(dev, "%s()\n", __func__);
 664
 665         genpd = dev_to_genpd(dev);
 666         if (IS_ERR(genpd))
 667                 return -EINVAL;
 668
 669         might_sleep_if(!genpd->dev_irq_safe);
 670
 671         /* If power.irq_safe, the PM domain is never powered off. */
 672         if (dev->power.irq_safe)
 673                 return genpd_start_dev_no_timing(genpd, dev);
 674
 675         mutex_lock(&genpd->lock);
 676         ret = __pm_genpd_poweron(genpd);
 677         if (ret) {
 678                 mutex_unlock(&genpd->lock);
 679                 return ret;
 680         }
 681         genpd->status = GPD_STATE_BUSY;
 682         genpd->resume_count++;
 683         for (;;) {
 684                 prepare_to_wait(&genpd->status_wait_queue, &wait,
 685                                 TASK_UNINTERRUPTIBLE);
 686                 /*
 687                  * If current is the powering off task, we have been called
 688                  * reentrantly from one of the device callbacks, so we should
 689                  * not wait.
 690                  */
 691                 if (!genpd->poweroff_task || genpd->poweroff_task == current)
 692                         break;
 693                 mutex_unlock(&genpd->lock);
 694
 695                 schedule();
 696
 697                 mutex_lock(&genpd->lock);
 698         }
 699         finish_wait(&genpd->status_wait_queue, &wait);
 700         __pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
 701         genpd->resume_count--;
 702         genpd_set_active(genpd);
 703         wake_up_all(&genpd->status_wait_queue);
 704         mutex_unlock(&genpd->lock);
 705
 706         return 0;
 707 }
 708
 709 /**
 710  * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
 711  */
 712 void pm_genpd_poweroff_unused(void)
 713 {
 714         struct generic_pm_domain *genpd;
 715
 716         mutex_lock(&gpd_list_lock);
 717
 718         list_for_each_entry(genpd, &gpd_list, gpd_list_node)
 719                 genpd_queue_power_off_work(genpd);
 720
 721         mutex_unlock(&gpd_list_lock);
 722 }
 723
 724 #else
 725
 726 static inline int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 727                                             unsigned long val, void *ptr)
 728 {
 729         return NOTIFY_DONE;
 730 }
 731
 732 static inline void genpd_power_off_work_fn(struct work_struct *work) {}
 733
 734 #define pm_genpd_runtime_suspend        NULL
 735 #define pm_genpd_runtime_resume         NULL
 736
 737 #endif /* CONFIG_PM_RUNTIME */
 738
 739 #ifdef CONFIG_PM_SLEEP
 740
 741 /**
 742  * pm_genpd_present - Check if the given PM domain has been initialized.
 743  * @genpd: PM domain to check.
 744  */
 745 static bool pm_genpd_present(struct generic_pm_domain *genpd)
 746 {
 747         struct generic_pm_domain *gpd;
 748
 749         if (IS_ERR_OR_NULL(genpd))
 750                 return false;
 751
 752         list_for_each_entry(gpd, &gpd_list, gpd_list_node)
 753                 if (gpd == genpd)
 754                         return true;
 755
 756         return false;
 757 }
 758
 759 static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
 760                                     struct device *dev)
 761 {
 762         return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
 763 }
 764
 765 static int genpd_suspend_dev(struct generic_pm_domain *genpd, struct device *dev)
 766 {
 767         return GENPD_DEV_CALLBACK(genpd, int, suspend, dev);
 768 }
 769
 770 static int genpd_suspend_late(struct generic_pm_domain *genpd, struct device *dev)
 771 {
 772         return GENPD_DEV_CALLBACK(genpd, int, suspend_late, dev);
 773 }
 774
 775 static int genpd_resume_early(struct generic_pm_domain *genpd, struct device *dev)
 776 {
 777         return GENPD_DEV_CALLBACK(genpd, int, resume_early, dev);
 778 }
 779
 780 static int genpd_resume_dev(struct generic_pm_domain *genpd, struct device *dev)
 781 {
 782         return GENPD_DEV_CALLBACK(genpd, int, resume, dev);
 783 }
 784
 785 static int genpd_freeze_dev(struct generic_pm_domain *genpd, struct device *dev)
 786 {
 787         return GENPD_DEV_CALLBACK(genpd, int, freeze, dev);
 788 }
 789
 790 static int genpd_freeze_late(struct generic_pm_domain *genpd, struct device *dev)
 791 {
 792         return GENPD_DEV_CALLBACK(genpd, int, freeze_late, dev);
 793 }
 794
 795 static int genpd_thaw_early(struct generic_pm_domain *genpd, struct device *dev)
 796 {
 797         return GENPD_DEV_CALLBACK(genpd, int, thaw_early, dev);
 798 }
 799
 800 static int genpd_thaw_dev(struct generic_pm_domain *genpd, struct device *dev)
 801 {
 802         return GENPD_DEV_CALLBACK(genpd, int, thaw, dev);
 803 }
 804
 805 /**
 806  * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
 807  * @genpd: PM domain to power off, if possible.
 808  *
 809  * Check if the given PM domain can be powered off (during system suspend or
 810  * hibernation) and do that if so.  Also, in that case propagate to its masters.
 811  *
 812  * This function is only called in "noirq" and "syscore" stages of system power
 813  * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 814  * executed sequentially, so it is guaranteed that it will never run twice in
 815  * parallel).
 816  */
 817 static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
 818 {
 819         struct gpd_link *link;
 820
 821         if (genpd->status == GPD_STATE_POWER_OFF)
 822                 return;
 823
 824         if (genpd->suspended_count != genpd->device_count
 825             || atomic_read(&genpd->sd_count) > 0)
 826                 return;
 827
 828         if (genpd->power_off)
 829                 genpd->power_off(genpd);
 830
 831         genpd->status = GPD_STATE_POWER_OFF;
 832
 833         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 834                 genpd_sd_counter_dec(link->master);
 835                 pm_genpd_sync_poweroff(link->master);
 836         }
 837 }
 838
 839 /**
 840  * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
 841  * @genpd: PM domain to power on.
 842  *
 843  * This function is only called in "noirq" and "syscore" stages of system power
 844  * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 845  * executed sequentially, so it is guaranteed that it will never run twice in
 846  * parallel).
 847  */
 848 static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd)
 849 {
 850         struct gpd_link *link;
 851
 852         if (genpd->status != GPD_STATE_POWER_OFF)
 853                 return;
 854
 855         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 856                 pm_genpd_sync_poweron(link->master);
 857                 genpd_sd_counter_inc(link->master);
 858         }
 859
 860         if (genpd->power_on)
 861                 genpd->power_on(genpd);
 862
 863         genpd->status = GPD_STATE_ACTIVE;
 864 }
 865
 866 /**
 867  * resume_needed - Check whether to resume a device before system suspend.
 868  * @dev: Device to check.
 869  * @genpd: PM domain the device belongs to.
 870  *
 871  * There are two cases in which a device that can wake up the system from sleep
 872  * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
 873  * to wake up the system and it has to remain active for this purpose while the
 874  * system is in the sleep state and (2) if the device is not enabled to wake up
 875  * the system from sleep states and it generally doesn't generate wakeup signals
 876  * by itself (those signals are generated on its behalf by other parts of the
 877  * system).  In the latter case it may be necessary to reconfigure the device's
 878  * wakeup settings during system suspend, because it may have been set up to
 879  * signal remote wakeup from the system's working state as needed by runtime PM.
 880  * Return 'true' in either of the above cases.
 881  */
 882 static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
 883 {
 884         bool active_wakeup;
 885
 886         if (!device_can_wakeup(dev))
 887                 return false;
 888
 889         active_wakeup = genpd_dev_active_wakeup(genpd, dev);
 890         return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
 891 }
 892
 893 /**
 894  * pm_genpd_prepare - Start power transition of a device in a PM domain.
 895  * @dev: Device to start the transition of.
 896  *
 897  * Start a power transition of a device (during a system-wide power transition)
 898  * under the assumption that its pm_domain field points to the domain member of
 899  * an object of type struct generic_pm_domain representing a PM domain
 900  * consisting of I/O devices.
 901  */
 902 static int pm_genpd_prepare(struct device *dev)
 903 {
 904         struct generic_pm_domain *genpd;
 905         int ret;
 906
 907         dev_dbg(dev, "%s()\n", __func__);
 908
 909         genpd = dev_to_genpd(dev);
 910         if (IS_ERR(genpd))
 911                 return -EINVAL;
 912
 913         /*
 914          * If a wakeup request is pending for the device, it should be woken up
 915          * at this point and a system wakeup event should be reported if it's
 916          * set up to wake up the system from sleep states.
 917          */
 918         pm_runtime_get_noresume(dev);
 919         if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
 920                 pm_wakeup_event(dev, 0);
 921
 922         if (pm_wakeup_pending()) {
 923                 pm_runtime_put(dev);
 924                 return -EBUSY;
 925         }
 926
 927         if (resume_needed(dev, genpd))
 928                 pm_runtime_resume(dev);
 929
 930         genpd_acquire_lock(genpd);
 931
 932         if (genpd->prepared_count++ == 0) {
 933                 genpd->suspended_count = 0;
 934                 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
 935         }
 936
 937         genpd_release_lock(genpd);
 938
 939         if (genpd->suspend_power_off) {
 940                 pm_runtime_put_noidle(dev);
 941                 return 0;
 942         }
 943
 944         /*
 945          * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
 946          * so pm_genpd_poweron() will return immediately, but if the device
 947          * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
 948          * to make it operational.
 949          */
 950         pm_runtime_resume(dev);
 951         __pm_runtime_disable(dev, false);
 952
 953         ret = pm_generic_prepare(dev);
 954         if (ret) {
 955                 mutex_lock(&genpd->lock);
 956
 957                 if (--genpd->prepared_count == 0)
 958                         genpd->suspend_power_off = false;
 959
 960                 mutex_unlock(&genpd->lock);
 961                 pm_runtime_enable(dev);
 962         }
 963
 964         pm_runtime_put(dev);
 965         return ret;
 966 }
 967
 968 /**
 969  * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
 970  * @dev: Device to suspend.
 971  *
 972  * Suspend a device under the assumption that its pm_domain field points to the
 973  * domain member of an object of type struct generic_pm_domain representing
 974  * a PM domain consisting of I/O devices.
 975  */
 976 static int pm_genpd_suspend(struct device *dev)
 977 {
 978         struct generic_pm_domain *genpd;
 979
 980         dev_dbg(dev, "%s()\n", __func__);
 981
 982         genpd = dev_to_genpd(dev);
 983         if (IS_ERR(genpd))
 984                 return -EINVAL;
 985
 986         return genpd->suspend_power_off ? 0 : genpd_suspend_dev(genpd, dev);
 987 }
 988
 989 /**
 990  * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
 991  * @dev: Device to suspend.
 992  *
 993  * Carry out a late suspend of a device under the assumption that its
 994  * pm_domain field points to the domain member of an object of type
 995  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 996  */
 997 static int pm_genpd_suspend_late(struct device *dev)
 998 {
 999         struct generic_pm_domain *genpd;
1000
1001         dev_dbg(dev, "%s()\n", __func__);
1002
1003         genpd = dev_to_genpd(dev);
1004         if (IS_ERR(genpd))
1005                 return -EINVAL;
1006
1007         return genpd->suspend_power_off ? 0 : genpd_suspend_late(genpd, dev);
1008 }
1009
1010 /**
1011  * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1012  * @dev: Device to suspend.
1013  *
1014  * Stop the device and remove power from the domain if all devices in it have
1015  * been stopped.
1016  */
1017 static int pm_genpd_suspend_noirq(struct device *dev)
1018 {
1019         struct generic_pm_domain *genpd;
1020
1021         dev_dbg(dev, "%s()\n", __func__);
1022
1023         genpd = dev_to_genpd(dev);
1024         if (IS_ERR(genpd))
1025                 return -EINVAL;
1026
1027         if (genpd->suspend_power_off
1028             || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1029                 return 0;
1030
1031         genpd_stop_dev(genpd, dev);
1032
1033         /*
1034          * Since all of the "noirq" callbacks are executed sequentially, it is
1035          * guaranteed that this function will never run twice in parallel for
1036          * the same PM domain, so it is not necessary to use locking here.
1037          */
1038         genpd->suspended_count++;
1039         pm_genpd_sync_poweroff(genpd);
1040
1041         return 0;
1042 }
1043
1044 /**
1045  * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1046  * @dev: Device to resume.
1047  *
1048  * Restore power to the device's PM domain, if necessary, and start the device.
1049  */
1050 static int pm_genpd_resume_noirq(struct device *dev)
1051 {
1052         struct generic_pm_domain *genpd;
1053
1054         dev_dbg(dev, "%s()\n", __func__);
1055
1056         genpd = dev_to_genpd(dev);
1057         if (IS_ERR(genpd))
1058                 return -EINVAL;
1059
1060         if (genpd->suspend_power_off
1061             || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1062                 return 0;
1063
1064         /*
1065          * Since all of the "noirq" callbacks are executed sequentially, it is
1066          * guaranteed that this function will never run twice in parallel for
1067          * the same PM domain, so it is not necessary to use locking here.
1068          */
1069         pm_genpd_sync_poweron(genpd);
1070         genpd->suspended_count--;
1071
1072         return genpd_start_dev(genpd, dev);
1073 }
1074
1075 /**
1076  * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
1077  * @dev: Device to resume.
1078  *
1079  * Carry out an early resume of a device under the assumption that its
1080  * pm_domain field points to the domain member of an object of type
1081  * struct generic_pm_domain representing a power domain consisting of I/O
1082  * devices.
1083  */
1084 static int pm_genpd_resume_early(struct device *dev)
1085 {
1086         struct generic_pm_domain *genpd;
1087
1088         dev_dbg(dev, "%s()\n", __func__);
1089
1090         genpd = dev_to_genpd(dev);
1091         if (IS_ERR(genpd))
1092                 return -EINVAL;
1093
1094         return genpd->suspend_power_off ? 0 : genpd_resume_early(genpd, dev);
1095 }
1096
1097 /**
1098  * pm_genpd_resume - Resume of device in an I/O PM domain.
1099  * @dev: Device to resume.
1100  *
1101  * Resume a device under the assumption that its pm_domain field points to the
1102  * domain member of an object of type struct generic_pm_domain representing
1103  * a power domain consisting of I/O devices.
1104  */
1105 static int pm_genpd_resume(struct device *dev)
1106 {
1107         struct generic_pm_domain *genpd;
1108
1109         dev_dbg(dev, "%s()\n", __func__);
1110
1111         genpd = dev_to_genpd(dev);
1112         if (IS_ERR(genpd))
1113                 return -EINVAL;
1114
1115         return genpd->suspend_power_off ? 0 : genpd_resume_dev(genpd, dev);
1116 }
1117
1118 /**
1119  * pm_genpd_freeze - Freezing a device in an I/O PM domain.
1120  * @dev: Device to freeze.
1121  *
1122  * Freeze a device under the assumption that its pm_domain field points to the
1123  * domain member of an object of type struct generic_pm_domain representing
1124  * a power domain consisting of I/O devices.
1125  */
1126 static int pm_genpd_freeze(struct device *dev)
1127 {
1128         struct generic_pm_domain *genpd;
1129
1130         dev_dbg(dev, "%s()\n", __func__);
1131
1132         genpd = dev_to_genpd(dev);
1133         if (IS_ERR(genpd))
1134                 return -EINVAL;
1135
1136         return genpd->suspend_power_off ? 0 : genpd_freeze_dev(genpd, dev);
1137 }
1138
1139 /**
1140  * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
1141  * @dev: Device to freeze.
1142  *
1143  * Carry out a late freeze of a device under the assumption that its
1144  * pm_domain field points to the domain member of an object of type
1145  * struct generic_pm_domain representing a power domain consisting of I/O
1146  * devices.
1147  */
1148 static int pm_genpd_freeze_late(struct device *dev)
1149 {
1150         struct generic_pm_domain *genpd;
1151
1152         dev_dbg(dev, "%s()\n", __func__);
1153
1154         genpd = dev_to_genpd(dev);
1155         if (IS_ERR(genpd))
1156                 return -EINVAL;
1157
1158         return genpd->suspend_power_off ? 0 : genpd_freeze_late(genpd, dev);
1159 }
1160
1161 /**
1162  * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1163  * @dev: Device to freeze.
1164  *
1165  * Carry out a late freeze of a device under the assumption that its
1166  * pm_domain field points to the domain member of an object of type
1167  * struct generic_pm_domain representing a power domain consisting of I/O
1168  * devices.
1169  */
1170 static int pm_genpd_freeze_noirq(struct device *dev)
1171 {
1172         struct generic_pm_domain *genpd;
1173
1174         dev_dbg(dev, "%s()\n", __func__);
1175
1176         genpd = dev_to_genpd(dev);
1177         if (IS_ERR(genpd))
1178                 return -EINVAL;
1179
1180         return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
1181 }
1182
1183 /**
1184  * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1185  * @dev: Device to thaw.
1186  *
1187  * Start the device, unless power has been removed from the domain already
1188  * before the system transition.
1189  */
1190 static int pm_genpd_thaw_noirq(struct device *dev)
1191 {
1192         struct generic_pm_domain *genpd;
1193
1194         dev_dbg(dev, "%s()\n", __func__);
1195
1196         genpd = dev_to_genpd(dev);
1197         if (IS_ERR(genpd))
1198                 return -EINVAL;
1199
1200         return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
1201 }
1202
1203 /**
1204  * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
1205  * @dev: Device to thaw.
1206  *
1207  * Carry out an early thaw of a device under the assumption that its
1208  * pm_domain field points to the domain member of an object of type
1209  * struct generic_pm_domain representing a power domain consisting of I/O
1210  * devices.
1211  */
1212 static int pm_genpd_thaw_early(struct device *dev)
1213 {
1214         struct generic_pm_domain *genpd;
1215
1216         dev_dbg(dev, "%s()\n", __func__);
1217
1218         genpd = dev_to_genpd(dev);
1219         if (IS_ERR(genpd))
1220                 return -EINVAL;
1221
1222         return genpd->suspend_power_off ? 0 : genpd_thaw_early(genpd, dev);
1223 }
1224
1225 /**
1226  * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1227  * @dev: Device to thaw.
1228  *
1229  * Thaw a device under the assumption that its pm_domain field points to the
1230  * domain member of an object of type struct generic_pm_domain representing
1231  * a power domain consisting of I/O devices.
1232  */
1233 static int pm_genpd_thaw(struct device *dev)
1234 {
1235         struct generic_pm_domain *genpd;
1236
1237         dev_dbg(dev, "%s()\n", __func__);
1238
1239         genpd = dev_to_genpd(dev);
1240         if (IS_ERR(genpd))
1241                 return -EINVAL;
1242
1243         return genpd->suspend_power_off ? 0 : genpd_thaw_dev(genpd, dev);
1244 }
1245
1246 /**
1247  * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1248  * @dev: Device to resume.
1249  *
1250  * Make sure the domain will be in the same power state as before the
1251  * hibernation the system is resuming from and start the device if necessary.
1252  */
1253 static int pm_genpd_restore_noirq(struct device *dev)
1254 {
1255         struct generic_pm_domain *genpd;
1256
1257         dev_dbg(dev, "%s()\n", __func__);
1258
1259         genpd = dev_to_genpd(dev);
1260         if (IS_ERR(genpd))
1261                 return -EINVAL;
1262
1263         /*
1264          * Since all of the "noirq" callbacks are executed sequentially, it is
1265          * guaranteed that this function will never run twice in parallel for
1266          * the same PM domain, so it is not necessary to use locking here.
1267          *
1268          * At this point suspended_count == 0 means we are being run for the
1269          * first time for the given domain in the present cycle.
1270          */
1271         if (genpd->suspended_count++ == 0) {
1272                 /*
1273                  * The boot kernel might put the domain into arbitrary state,
1274                  * so make it appear as powered off to pm_genpd_sync_poweron(),
1275                  * so that it tries to power it on in case it was really off.
1276                  */
1277                 genpd->status = GPD_STATE_POWER_OFF;
1278                 if (genpd->suspend_power_off) {
1279                         /*
1280                          * If the domain was off before the hibernation, make
1281                          * sure it will be off going forward.
1282                          */
1283                         if (genpd->power_off)
1284                                 genpd->power_off(genpd);
1285
1286                         return 0;
1287                 }
1288         }
1289
1290         if (genpd->suspend_power_off)
1291                 return 0;
1292
1293         pm_genpd_sync_poweron(genpd);
1294
1295         return genpd_start_dev(genpd, dev);
1296 }
1297
1298 /**
1299  * pm_genpd_complete - Complete power transition of a device in a power domain.
1300  * @dev: Device to complete the transition of.
1301  *
1302  * Complete a power transition of a device (during a system-wide power
1303  * transition) under the assumption that its pm_domain field points to the
1304  * domain member of an object of type struct generic_pm_domain representing
1305  * a power domain consisting of I/O devices.
1306  */
1307 static void pm_genpd_complete(struct device *dev)
1308 {
1309         struct generic_pm_domain *genpd;
1310         bool run_complete;
1311
1312         dev_dbg(dev, "%s()\n", __func__);
1313
1314         genpd = dev_to_genpd(dev);
1315         if (IS_ERR(genpd))
1316                 return;
1317
1318         mutex_lock(&genpd->lock);
1319
1320         run_complete = !genpd->suspend_power_off;
1321         if (--genpd->prepared_count == 0)
1322                 genpd->suspend_power_off = false;
1323
1324         mutex_unlock(&genpd->lock);
1325
1326         if (run_complete) {
1327                 pm_generic_complete(dev);
1328                 pm_runtime_set_active(dev);
1329                 pm_runtime_enable(dev);
1330                 pm_request_idle(dev);
1331         }
1332 }
1333
1334 /**
1335  * pm_genpd_syscore_switch - Switch power during system core suspend or resume.
1336  * @dev: Device that normally is marked as "always on" to switch power for.
1337  *
1338  * This routine may only be called during the system core (syscore) suspend or
1339  * resume phase for devices whose "always on" flags are set.
1340  */
1341 void pm_genpd_syscore_switch(struct device *dev, bool suspend)
1342 {
1343         struct generic_pm_domain *genpd;
1344
1345         genpd = dev_to_genpd(dev);
1346         if (!pm_genpd_present(genpd))
1347                 return;
1348
1349         if (suspend) {
1350                 genpd->suspended_count++;
1351                 pm_genpd_sync_poweroff(genpd);
1352         } else {
1353                 pm_genpd_sync_poweron(genpd);
1354                 genpd->suspended_count--;
1355         }
1356 }
1357 EXPORT_SYMBOL_GPL(pm_genpd_syscore_switch);
1358
1359 #else
1360
1361 #define pm_genpd_prepare                NULL
1362 #define pm_genpd_suspend                NULL
1363 #define pm_genpd_suspend_late           NULL
1364 #define pm_genpd_suspend_noirq          NULL
1365 #define pm_genpd_resume_early           NULL
1366 #define pm_genpd_resume_noirq           NULL
1367 #define pm_genpd_resume                 NULL
1368 #define pm_genpd_freeze                 NULL
1369 #define pm_genpd_freeze_late            NULL
1370 #define pm_genpd_freeze_noirq           NULL
1371 #define pm_genpd_thaw_early             NULL
1372 #define pm_genpd_thaw_noirq             NULL
1373 #define pm_genpd_thaw                   NULL
1374 #define pm_genpd_restore_noirq          NULL
1375 #define pm_genpd_complete               NULL
1376
1377 #endif /* CONFIG_PM_SLEEP */
1378
1379 static struct generic_pm_domain_data *__pm_genpd_alloc_dev_data(struct device *dev)
1380 {
1381         struct generic_pm_domain_data *gpd_data;
1382
1383         gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1384         if (!gpd_data)
1385                 return NULL;
1386
1387         mutex_init(&gpd_data->lock);
1388         gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1389         dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1390         return gpd_data;
1391 }
1392
1393 static void __pm_genpd_free_dev_data(struct device *dev,
1394                                      struct generic_pm_domain_data *gpd_data)
1395 {
1396         dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1397         kfree(gpd_data);
1398 }
1399
1400 /**
1401  * __pm_genpd_add_device - Add a device to an I/O PM domain.
1402  * @genpd: PM domain to add the device to.
1403  * @dev: Device to be added.
1404  * @td: Set of PM QoS timing parameters to attach to the device.
1405  */
1406 int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1407                           struct gpd_timing_data *td)
1408 {
1409         struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1410         struct pm_domain_data *pdd;
1411         int ret = 0;
1412
1413         dev_dbg(dev, "%s()\n", __func__);
1414
1415         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1416                 return -EINVAL;
1417
1418         gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1419         if (!gpd_data_new)
1420                 return -ENOMEM;
1421
1422         genpd_acquire_lock(genpd);
1423
1424         if (genpd->prepared_count > 0) {
1425                 ret = -EAGAIN;
1426                 goto out;
1427         }
1428
1429         list_for_each_entry(pdd, &genpd->dev_list, list_node)
1430                 if (pdd->dev == dev) {
1431                         ret = -EINVAL;
1432                         goto out;
1433                 }
1434
1435         ret = dev_pm_get_subsys_data(dev);
1436         if (ret)
1437                 goto out;
1438
1439         genpd->device_count++;
1440         genpd->max_off_time_changed = true;
1441
1442         spin_lock_irq(&dev->power.lock);
1443
1444         dev->pm_domain = &genpd->domain;
1445         if (dev->power.subsys_data->domain_data) {
1446                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1447         } else {
1448                 gpd_data = gpd_data_new;
1449                 dev->power.subsys_data->domain_data = &gpd_data->base;
1450         }
1451         gpd_data->refcount++;
1452         if (td)
1453                 gpd_data->td = *td;
1454
1455         spin_unlock_irq(&dev->power.lock);
1456
1457         mutex_lock(&gpd_data->lock);
1458         gpd_data->base.dev = dev;
1459         list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1460         gpd_data->need_restore = genpd->status == GPD_STATE_POWER_OFF;
1461         gpd_data->td.constraint_changed = true;
1462         gpd_data->td.effective_constraint_ns = -1;
1463         mutex_unlock(&gpd_data->lock);
1464
1465  out:
1466         genpd_release_lock(genpd);
1467
1468         if (gpd_data != gpd_data_new)
1469                 __pm_genpd_free_dev_data(dev, gpd_data_new);
1470
1471         return ret;
1472 }
1473
1474 /**
1475  * __pm_genpd_of_add_device - Add a device to an I/O PM domain.
1476  * @genpd_node: Device tree node pointer representing a PM domain to which the
1477  *   the device is added to.
1478  * @dev: Device to be added.
1479  * @td: Set of PM QoS timing parameters to attach to the device.
1480  */
1481 int __pm_genpd_of_add_device(struct device_node *genpd_node, struct device *dev,
1482                              struct gpd_timing_data *td)
1483 {
1484         struct generic_pm_domain *genpd = NULL, *gpd;
1485
1486         dev_dbg(dev, "%s()\n", __func__);
1487
1488         if (IS_ERR_OR_NULL(genpd_node) || IS_ERR_OR_NULL(dev))
1489                 return -EINVAL;
1490
1491         mutex_lock(&gpd_list_lock);
1492         list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1493                 if (gpd->of_node == genpd_node) {
1494                         genpd = gpd;
1495                         break;
1496                 }
1497         }
1498         mutex_unlock(&gpd_list_lock);
1499
1500         if (!genpd)
1501                 return -EINVAL;
1502
1503         return __pm_genpd_add_device(genpd, dev, td);
1504 }
1505
1506
1507 /**
1508  * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
1509  * @domain_name: Name of the PM domain to add the device to.
1510  * @dev: Device to be added.
1511  * @td: Set of PM QoS timing parameters to attach to the device.
1512  */
1513 int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
1514                                struct gpd_timing_data *td)
1515 {
1516         return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
1517 }
1518
1519 /**
1520  * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1521  * @genpd: PM domain to remove the device from.
1522  * @dev: Device to be removed.
1523  */
1524 int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1525                            struct device *dev)
1526 {
1527         struct generic_pm_domain_data *gpd_data;
1528         struct pm_domain_data *pdd;
1529         bool remove = false;
1530         int ret = 0;
1531
1532         dev_dbg(dev, "%s()\n", __func__);
1533
1534         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)
1535             ||  IS_ERR_OR_NULL(dev->pm_domain)
1536             ||  pd_to_genpd(dev->pm_domain) != genpd)
1537                 return -EINVAL;
1538
1539         genpd_acquire_lock(genpd);
1540
1541         if (genpd->prepared_count > 0) {
1542                 ret = -EAGAIN;
1543                 goto out;
1544         }
1545
1546         genpd->device_count--;
1547         genpd->max_off_time_changed = true;
1548
1549         spin_lock_irq(&dev->power.lock);
1550
1551         dev->pm_domain = NULL;
1552         pdd = dev->power.subsys_data->domain_data;
1553         list_del_init(&pdd->list_node);
1554         gpd_data = to_gpd_data(pdd);
1555         if (--gpd_data->refcount == 0) {
1556                 dev->power.subsys_data->domain_data = NULL;
1557                 remove = true;
1558         }
1559
1560         spin_unlock_irq(&dev->power.lock);
1561
1562         mutex_lock(&gpd_data->lock);
1563         pdd->dev = NULL;
1564         mutex_unlock(&gpd_data->lock);
1565
1566         genpd_release_lock(genpd);
1567
1568         dev_pm_put_subsys_data(dev);
1569         if (remove)
1570                 __pm_genpd_free_dev_data(dev, gpd_data);
1571
1572         return 0;
1573
1574  out:
1575         genpd_release_lock(genpd);
1576
1577         return ret;
1578 }
1579
1580 /**
1581  * pm_genpd_dev_need_restore - Set/unset the device's "need restore" flag.
1582  * @dev: Device to set/unset the flag for.
1583  * @val: The new value of the device's "need restore" flag.
1584  */
1585 void pm_genpd_dev_need_restore(struct device *dev, bool val)
1586 {
1587         struct pm_subsys_data *psd;
1588         unsigned long flags;
1589
1590         spin_lock_irqsave(&dev->power.lock, flags);
1591
1592         psd = dev_to_psd(dev);
1593         if (psd && psd->domain_data)
1594                 to_gpd_data(psd->domain_data)->need_restore = val;
1595
1596         spin_unlock_irqrestore(&dev->power.lock, flags);
1597 }
1598 EXPORT_SYMBOL_GPL(pm_genpd_dev_need_restore);
1599
1600 /**
1601  * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1602  * @genpd: Master PM domain to add the subdomain to.
1603  * @subdomain: Subdomain to be added.
1604  */
1605 int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1606                            struct generic_pm_domain *subdomain)
1607 {
1608         struct gpd_link *link;
1609         int ret = 0;
1610
1611         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1612             || genpd == subdomain)
1613                 return -EINVAL;
1614
1615  start:
1616         genpd_acquire_lock(genpd);
1617         mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1618
1619         if (subdomain->status != GPD_STATE_POWER_OFF
1620             && subdomain->status != GPD_STATE_ACTIVE) {
1621                 mutex_unlock(&subdomain->lock);
1622                 genpd_release_lock(genpd);
1623                 goto start;
1624         }
1625
1626         if (genpd->status == GPD_STATE_POWER_OFF
1627             &&  subdomain->status != GPD_STATE_POWER_OFF) {
1628                 ret = -EINVAL;
1629                 goto out;
1630         }
1631
1632         list_for_each_entry(link, &genpd->master_links, master_node) {
1633                 if (link->slave == subdomain && link->master == genpd) {
1634                         ret = -EINVAL;
1635                         goto out;
1636                 }
1637         }
1638
1639         link = kzalloc(sizeof(*link), GFP_KERNEL);
1640         if (!link) {
1641                 ret = -ENOMEM;
1642                 goto out;
1643         }
1644         link->master = genpd;
1645         list_add_tail(&link->master_node, &genpd->master_links);
1646         link->slave = subdomain;
1647         list_add_tail(&link->slave_node, &subdomain->slave_links);
1648         if (subdomain->status != GPD_STATE_POWER_OFF)
1649                 genpd_sd_counter_inc(genpd);
1650
1651  out:
1652         mutex_unlock(&subdomain->lock);
1653         genpd_release_lock(genpd);
1654
1655         return ret;
1656 }
1657
1658 /**
1659  * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
1660  * @master_name: Name of the master PM domain to add the subdomain to.
1661  * @subdomain_name: Name of the subdomain to be added.
1662  */
1663 int pm_genpd_add_subdomain_names(const char *master_name,
1664                                  const char *subdomain_name)
1665 {
1666         struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
1667
1668         if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
1669                 return -EINVAL;
1670
1671         mutex_lock(&gpd_list_lock);
1672         list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1673                 if (!master && !strcmp(gpd->name, master_name))
1674                         master = gpd;
1675
1676                 if (!subdomain && !strcmp(gpd->name, subdomain_name))
1677                         subdomain = gpd;
1678
1679                 if (master && subdomain)
1680                         break;
1681         }
1682         mutex_unlock(&gpd_list_lock);
1683
1684         return pm_genpd_add_subdomain(master, subdomain);
1685 }
1686
1687 /**
1688  * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1689  * @genpd: Master PM domain to remove the subdomain from.
1690  * @subdomain: Subdomain to be removed.
1691  */
1692 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1693                               struct generic_pm_domain *subdomain)
1694 {
1695         struct gpd_link *link;
1696         int ret = -EINVAL;
1697
1698         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1699                 return -EINVAL;
1700
1701  start:
1702         genpd_acquire_lock(genpd);
1703
1704         list_for_each_entry(link, &genpd->master_links, master_node) {
1705                 if (link->slave != subdomain)
1706                         continue;
1707
1708                 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1709
1710                 if (subdomain->status != GPD_STATE_POWER_OFF
1711                     && subdomain->status != GPD_STATE_ACTIVE) {
1712                         mutex_unlock(&subdomain->lock);
1713                         genpd_release_lock(genpd);
1714                         goto start;
1715                 }
1716
1717                 list_del(&link->master_node);
1718                 list_del(&link->slave_node);
1719                 kfree(link);
1720                 if (subdomain->status != GPD_STATE_POWER_OFF)
1721                         genpd_sd_counter_dec(genpd);
1722
1723                 mutex_unlock(&subdomain->lock);
1724
1725                 ret = 0;
1726                 break;
1727         }
1728
1729         genpd_release_lock(genpd);
1730
1731         return ret;
1732 }
1733
1734 /**
1735  * pm_genpd_add_callbacks - Add PM domain callbacks to a given device.
1736  * @dev: Device to add the callbacks to.
1737  * @ops: Set of callbacks to add.
1738  * @td: Timing data to add to the device along with the callbacks (optional).
1739  *
1740  * Every call to this routine should be balanced with a call to
1741  * __pm_genpd_remove_callbacks() and they must not be nested.
1742  */
1743 int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops,
1744                            struct gpd_timing_data *td)
1745 {
1746         struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1747         int ret = 0;
1748
1749         if (!(dev && ops))
1750                 return -EINVAL;
1751
1752         gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1753         if (!gpd_data_new)
1754                 return -ENOMEM;
1755
1756         pm_runtime_disable(dev);
1757         device_pm_lock();
1758
1759         ret = dev_pm_get_subsys_data(dev);
1760         if (ret)
1761                 goto out;
1762
1763         spin_lock_irq(&dev->power.lock);
1764
1765         if (dev->power.subsys_data->domain_data) {
1766                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1767         } else {
1768                 gpd_data = gpd_data_new;
1769                 dev->power.subsys_data->domain_data = &gpd_data->base;
1770         }
1771         gpd_data->refcount++;
1772         gpd_data->ops = *ops;
1773         if (td)
1774                 gpd_data->td = *td;
1775
1776         spin_unlock_irq(&dev->power.lock);
1777
1778  out:
1779         device_pm_unlock();
1780         pm_runtime_enable(dev);
1781
1782         if (gpd_data != gpd_data_new)
1783                 __pm_genpd_free_dev_data(dev, gpd_data_new);
1784
1785         return ret;
1786 }
1787 EXPORT_SYMBOL_GPL(pm_genpd_add_callbacks);
1788
1789 /**
1790  * __pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device.
1791  * @dev: Device to remove the callbacks from.
1792  * @clear_td: If set, clear the device's timing data too.
1793  *
1794  * This routine can only be called after pm_genpd_add_callbacks().
1795  */
1796 int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td)
1797 {
1798         struct generic_pm_domain_data *gpd_data = NULL;
1799         bool remove = false;
1800         int ret = 0;
1801
1802         if (!(dev && dev->power.subsys_data))
1803                 return -EINVAL;
1804
1805         pm_runtime_disable(dev);
1806         device_pm_lock();
1807
1808         spin_lock_irq(&dev->power.lock);
1809
1810         if (dev->power.subsys_data->domain_data) {
1811                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1812                 gpd_data->ops = (struct gpd_dev_ops){ NULL };
1813                 if (clear_td)
1814                         gpd_data->td = (struct gpd_timing_data){ 0 };
1815
1816                 if (--gpd_data->refcount == 0) {
1817                         dev->power.subsys_data->domain_data = NULL;
1818                         remove = true;
1819                 }
1820         } else {
1821                 ret = -EINVAL;
1822         }
1823
1824         spin_unlock_irq(&dev->power.lock);
1825
1826         device_pm_unlock();
1827         pm_runtime_enable(dev);
1828
1829         if (ret)
1830                 return ret;
1831
1832         dev_pm_put_subsys_data(dev);
1833         if (remove)
1834                 __pm_genpd_free_dev_data(dev, gpd_data);
1835
1836         return 0;
1837 }
1838 EXPORT_SYMBOL_GPL(__pm_genpd_remove_callbacks);
1839
1840 /**
1841  * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
1842  * @genpd: PM domain to be connected with cpuidle.
1843  * @state: cpuidle state this domain can disable/enable.
1844  *
1845  * Make a PM domain behave as though it contained a CPU core, that is, instead
1846  * of calling its power down routine it will enable the given cpuidle state so
1847  * that the cpuidle subsystem can power it down (if possible and desirable).
1848  */
1849 int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
1850 {
1851         struct cpuidle_driver *cpuidle_drv;
1852         struct gpd_cpu_data *cpu_data;
1853         struct cpuidle_state *idle_state;
1854         int ret = 0;
1855
1856         if (IS_ERR_OR_NULL(genpd) || state < 0)
1857                 return -EINVAL;
1858
1859         genpd_acquire_lock(genpd);
1860
1861         if (genpd->cpu_data) {
1862                 ret = -EEXIST;
1863                 goto out;
1864         }
1865         cpu_data = kzalloc(sizeof(*cpu_data), GFP_KERNEL);
1866         if (!cpu_data) {
1867                 ret = -ENOMEM;
1868                 goto out;
1869         }
1870         cpuidle_drv = cpuidle_driver_ref();
1871         if (!cpuidle_drv) {
1872                 ret = -ENODEV;
1873                 goto err_drv;
1874         }
1875         if (cpuidle_drv->state_count <= state) {
1876                 ret = -EINVAL;
1877                 goto err;
1878         }
1879         idle_state = &cpuidle_drv->states[state];
1880         if (!idle_state->disabled) {
1881                 ret = -EAGAIN;
1882                 goto err;
1883         }
1884         cpu_data->idle_state = idle_state;
1885         cpu_data->saved_exit_latency = idle_state->exit_latency;
1886         genpd->cpu_data = cpu_data;
1887         genpd_recalc_cpu_exit_latency(genpd);
1888
1889  out:
1890         genpd_release_lock(genpd);
1891         return ret;
1892
1893  err:
1894         cpuidle_driver_unref();
1895
1896  err_drv:
1897         kfree(cpu_data);
1898         goto out;
1899 }
1900
1901 /**
1902  * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
1903  * @name: Name of the domain to connect to cpuidle.
1904  * @state: cpuidle state this domain can manipulate.
1905  */
1906 int pm_genpd_name_attach_cpuidle(const char *name, int state)
1907 {
1908         return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
1909 }
1910
1911 /**
1912  * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
1913  * @genpd: PM domain to remove the cpuidle connection from.
1914  *
1915  * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
1916  * given PM domain.
1917  */
1918 int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
1919 {
1920         struct gpd_cpu_data *cpu_data;
1921         struct cpuidle_state *idle_state;
1922         int ret = 0;
1923
1924         if (IS_ERR_OR_NULL(genpd))
1925                 return -EINVAL;
1926
1927         genpd_acquire_lock(genpd);
1928
1929         cpu_data = genpd->cpu_data;
1930         if (!cpu_data) {
1931                 ret = -ENODEV;
1932                 goto out;
1933         }
1934         idle_state = cpu_data->idle_state;
1935         if (!idle_state->disabled) {
1936                 ret = -EAGAIN;
1937                 goto out;
1938         }
1939         idle_state->exit_latency = cpu_data->saved_exit_latency;
1940         cpuidle_driver_unref();
1941         genpd->cpu_data = NULL;
1942         kfree(cpu_data);
1943
1944  out:
1945         genpd_release_lock(genpd);
1946         return ret;
1947 }
1948
1949 /**
1950  * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
1951  * @name: Name of the domain to disconnect cpuidle from.
1952  */
1953 int pm_genpd_name_detach_cpuidle(const char *name)
1954 {
1955         return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
1956 }
1957
1958 /* Default device callbacks for generic PM domains. */
1959
1960 /**
1961  * pm_genpd_default_save_state - Default "save device state" for PM domians.
1962  * @dev: Device to handle.
1963  */
1964 static int pm_genpd_default_save_state(struct device *dev)
1965 {
1966         int (*cb)(struct device *__dev);
1967
1968         cb = dev_gpd_data(dev)->ops.save_state;
1969         if (cb)
1970                 return cb(dev);
1971
1972         if (dev->type && dev->type->pm)
1973                 cb = dev->type->pm->runtime_suspend;
1974         else if (dev->class && dev->class->pm)
1975                 cb = dev->class->pm->runtime_suspend;
1976         else if (dev->bus && dev->bus->pm)
1977                 cb = dev->bus->pm->runtime_suspend;
1978         else
1979                 cb = NULL;
1980
1981         if (!cb && dev->driver && dev->driver->pm)
1982                 cb = dev->driver->pm->runtime_suspend;
1983
1984         return cb ? cb(dev) : 0;
1985 }
1986
1987 /**
1988  * pm_genpd_default_restore_state - Default PM domians "restore device state".
1989  * @dev: Device to handle.
1990  */
1991 static int pm_genpd_default_restore_state(struct device *dev)
1992 {
1993         int (*cb)(struct device *__dev);
1994
1995         cb = dev_gpd_data(dev)->ops.restore_state;
1996         if (cb)
1997                 return cb(dev);
1998
1999         if (dev->type && dev->type->pm)
2000                 cb = dev->type->pm->runtime_resume;
2001         else if (dev->class && dev->class->pm)
2002                 cb = dev->class->pm->runtime_resume;
2003         else if (dev->bus && dev->bus->pm)
2004                 cb = dev->bus->pm->runtime_resume;
2005         else
2006                 cb = NULL;
2007
2008         if (!cb && dev->driver && dev->driver->pm)
2009                 cb = dev->driver->pm->runtime_resume;
2010
2011         return cb ? cb(dev) : 0;
2012 }
2013
2014 #ifdef CONFIG_PM_SLEEP
2015
2016 /**
2017  * pm_genpd_default_suspend - Default "device suspend" for PM domians.
2018  * @dev: Device to handle.
2019  */
2020 static int pm_genpd_default_suspend(struct device *dev)
2021 {
2022         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend;
2023
2024         return cb ? cb(dev) : pm_generic_suspend(dev);
2025 }
2026
2027 /**
2028  * pm_genpd_default_suspend_late - Default "late device suspend" for PM domians.
2029  * @dev: Device to handle.
2030  */
2031 static int pm_genpd_default_suspend_late(struct device *dev)
2032 {
2033         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend_late;
2034
2035         return cb ? cb(dev) : pm_generic_suspend_late(dev);
2036 }
2037
2038 /**
2039  * pm_genpd_default_resume_early - Default "early device resume" for PM domians.
2040  * @dev: Device to handle.
2041  */
2042 static int pm_genpd_default_resume_early(struct device *dev)
2043 {
2044         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume_early;
2045
2046         return cb ? cb(dev) : pm_generic_resume_early(dev);
2047 }
2048
2049 /**
2050  * pm_genpd_default_resume - Default "device resume" for PM domians.
2051  * @dev: Device to handle.
2052  */
2053 static int pm_genpd_default_resume(struct device *dev)
2054 {
2055         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume;
2056
2057         return cb ? cb(dev) : pm_generic_resume(dev);
2058 }
2059
2060 /**
2061  * pm_genpd_default_freeze - Default "device freeze" for PM domians.
2062  * @dev: Device to handle.
2063  */
2064 static int pm_genpd_default_freeze(struct device *dev)
2065 {
2066         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze;
2067
2068         return cb ? cb(dev) : pm_generic_freeze(dev);
2069 }
2070
2071 /**
2072  * pm_genpd_default_freeze_late - Default "late device freeze" for PM domians.
2073  * @dev: Device to handle.
2074  */
2075 static int pm_genpd_default_freeze_late(struct device *dev)
2076 {
2077         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late;
2078
2079         return cb ? cb(dev) : pm_generic_freeze_late(dev);
2080 }
2081
2082 /**
2083  * pm_genpd_default_thaw_early - Default "early device thaw" for PM domians.
2084  * @dev: Device to handle.
2085  */
2086 static int pm_genpd_default_thaw_early(struct device *dev)
2087 {
2088         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early;
2089
2090         return cb ? cb(dev) : pm_generic_thaw_early(dev);
2091 }
2092
2093 /**
2094  * pm_genpd_default_thaw - Default "device thaw" for PM domians.
2095  * @dev: Device to handle.
2096  */
2097 static int pm_genpd_default_thaw(struct device *dev)
2098 {
2099         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw;
2100
2101         return cb ? cb(dev) : pm_generic_thaw(dev);
2102 }
2103
2104 #else /* !CONFIG_PM_SLEEP */
2105
2106 #define pm_genpd_default_suspend        NULL
2107 #define pm_genpd_default_suspend_late   NULL
2108 #define pm_genpd_default_resume_early   NULL
2109 #define pm_genpd_default_resume         NULL
2110 #define pm_genpd_default_freeze         NULL
2111 #define pm_genpd_default_freeze_late    NULL
2112 #define pm_genpd_default_thaw_early     NULL
2113 #define pm_genpd_default_thaw           NULL
2114
2115 #endif /* !CONFIG_PM_SLEEP */
2116
2117 /**
2118  * pm_genpd_init - Initialize a generic I/O PM domain object.
2119  * @genpd: PM domain object to initialize.
2120  * @gov: PM domain governor to associate with the domain (may be NULL).
2121  * @is_off: Initial value of the domain's power_is_off field.
2122  */
2123 void pm_genpd_init(struct generic_pm_domain *genpd,
2124                    struct dev_power_governor *gov, bool is_off)
2125 {
2126         if (IS_ERR_OR_NULL(genpd))
2127                 return;
2128
2129         INIT_LIST_HEAD(&genpd->master_links);
2130         INIT_LIST_HEAD(&genpd->slave_links);
2131         INIT_LIST_HEAD(&genpd->dev_list);
2132         mutex_init(&genpd->lock);
2133         genpd->gov = gov;
2134         INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2135         genpd->in_progress = 0;
2136         atomic_set(&genpd->sd_count, 0);
2137         genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
2138         init_waitqueue_head(&genpd->status_wait_queue);
2139         genpd->poweroff_task = NULL;
2140         genpd->resume_count = 0;
2141         genpd->device_count = 0;
2142         genpd->max_off_time_ns = -1;
2143         genpd->max_off_time_changed = true;
2144         genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
2145         genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
2146         genpd->domain.ops.prepare = pm_genpd_prepare;
2147         genpd->domain.ops.suspend = pm_genpd_suspend;
2148         genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
2149         genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
2150         genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
2151         genpd->domain.ops.resume_early = pm_genpd_resume_early;
2152         genpd->domain.ops.resume = pm_genpd_resume;
2153         genpd->domain.ops.freeze = pm_genpd_freeze;
2154         genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
2155         genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
2156         genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
2157         genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
2158         genpd->domain.ops.thaw = pm_genpd_thaw;
2159         genpd->domain.ops.poweroff = pm_genpd_suspend;
2160         genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
2161         genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
2162         genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
2163         genpd->domain.ops.restore_early = pm_genpd_resume_early;
2164         genpd->domain.ops.restore = pm_genpd_resume;
2165         genpd->domain.ops.complete = pm_genpd_complete;
2166         genpd->dev_ops.save_state = pm_genpd_default_save_state;
2167         genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
2168         genpd->dev_ops.suspend = pm_genpd_default_suspend;
2169         genpd->dev_ops.suspend_late = pm_genpd_default_suspend_late;
2170         genpd->dev_ops.resume_early = pm_genpd_default_resume_early;
2171         genpd->dev_ops.resume = pm_genpd_default_resume;
2172         genpd->dev_ops.freeze = pm_genpd_default_freeze;
2173         genpd->dev_ops.freeze_late = pm_genpd_default_freeze_late;
2174         genpd->dev_ops.thaw_early = pm_genpd_default_thaw_early;
2175         genpd->dev_ops.thaw = pm_genpd_default_thaw;
2176         mutex_lock(&gpd_list_lock);
2177         list_add(&genpd->gpd_list_node, &gpd_list);
2178         mutex_unlock(&gpd_list_lock);
2179 }