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