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/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         if (!work_pending(&genpd->power_off_work))
 437                 queue_work(pm_wq, &genpd->power_off_work);
 438 }
 439
 440 /**
 441  * pm_genpd_poweroff - Remove power from a given PM domain.
 442  * @genpd: PM domain to power down.
 443  *
 444  * If all of the @genpd's devices have been suspended and all of its subdomains
 445  * have been powered down, run the runtime suspend callbacks provided by all of
 446  * the @genpd's devices' drivers and remove power from @genpd.
 447  */
 448 static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
 449         __releases(&genpd->lock) __acquires(&genpd->lock)
 450 {
 451         struct pm_domain_data *pdd;
 452         struct gpd_link *link;
 453         unsigned int not_suspended;
 454         int ret = 0;
 455
 456  start:
 457         /*
 458          * Do not try to power off the domain in the following situations:
 459          * (1) The domain is already in the "power off" state.
 460          * (2) The domain is waiting for its master to power up.
 461          * (3) One of the domain's devices is being resumed right now.
 462          * (4) System suspend is in progress.
 463          */
 464         if (genpd->status == GPD_STATE_POWER_OFF
 465             || genpd->status == GPD_STATE_WAIT_MASTER
 466             || genpd->resume_count > 0 || genpd->prepared_count > 0)
 467                 return 0;
 468
 469         if (atomic_read(&genpd->sd_count) > 0)
 470                 return -EBUSY;
 471
 472         not_suspended = 0;
 473         list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 474                 enum pm_qos_flags_status stat;
 475
 476                 stat = dev_pm_qos_flags(pdd->dev,
 477                                         PM_QOS_FLAG_NO_POWER_OFF
 478                                                 | PM_QOS_FLAG_REMOTE_WAKEUP);
 479                 if (stat > PM_QOS_FLAGS_NONE)
 480                         return -EBUSY;
 481
 482                 if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
 483                     || pdd->dev->power.irq_safe))
 484                         not_suspended++;
 485         }
 486
 487         if (not_suspended > genpd->in_progress)
 488                 return -EBUSY;
 489
 490         if (genpd->poweroff_task) {
 491                 /*
 492                  * Another instance of pm_genpd_poweroff() is executing
 493                  * callbacks, so tell it to start over and return.
 494                  */
 495                 genpd->status = GPD_STATE_REPEAT;
 496                 return 0;
 497         }
 498
 499         if (genpd->gov && genpd->gov->power_down_ok) {
 500                 if (!genpd->gov->power_down_ok(&genpd->domain))
 501                         return -EAGAIN;
 502         }
 503
 504         genpd->status = GPD_STATE_BUSY;
 505         genpd->poweroff_task = current;
 506
 507         list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
 508                 ret = atomic_read(&genpd->sd_count) == 0 ?
 509                         __pm_genpd_save_device(pdd, genpd) : -EBUSY;
 510
 511                 if (genpd_abort_poweroff(genpd))
 512                         goto out;
 513
 514                 if (ret) {
 515                         genpd_set_active(genpd);
 516                         goto out;
 517                 }
 518
 519                 if (genpd->status == GPD_STATE_REPEAT) {
 520                         genpd->poweroff_task = NULL;
 521                         goto start;
 522                 }
 523         }
 524
 525         if (genpd->cpu_data) {
 526                 /*
 527                  * If cpu_data is set, cpuidle should turn the domain off when
 528                  * the CPU in it is idle.  In that case we don't decrement the
 529                  * subdomain counts of the master domains, so that power is not
 530                  * removed from the current domain prematurely as a result of
 531                  * cutting off the masters' power.
 532                  */
 533                 genpd->status = GPD_STATE_POWER_OFF;
 534                 cpuidle_pause_and_lock();
 535                 genpd->cpu_data->idle_state->disabled = false;
 536                 cpuidle_resume_and_unlock();
 537                 goto out;
 538         }
 539
 540         if (genpd->power_off) {
 541                 ktime_t time_start;
 542                 s64 elapsed_ns;
 543
 544                 if (atomic_read(&genpd->sd_count) > 0) {
 545                         ret = -EBUSY;
 546                         goto out;
 547                 }
 548
 549                 time_start = ktime_get();
 550
 551                 /*
 552                  * If sd_count > 0 at this point, one of the subdomains hasn't
 553                  * managed to call pm_genpd_poweron() for the master yet after
 554                  * incrementing it.  In that case pm_genpd_poweron() will wait
 555                  * for us to drop the lock, so we can call .power_off() and let
 556                  * the pm_genpd_poweron() restore power for us (this shouldn't
 557                  * happen very often).
 558                  */
 559                 ret = genpd->power_off(genpd);
 560                 if (ret == -EBUSY) {
 561                         genpd_set_active(genpd);
 562                         goto out;
 563                 }
 564
 565                 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 566                 if (elapsed_ns > genpd->power_off_latency_ns) {
 567                         genpd->power_off_latency_ns = elapsed_ns;
 568                         genpd->max_off_time_changed = true;
 569                         if (genpd->name)
 570                                 pr_warning("%s: Power-off latency exceeded, "
 571                                         "new value %lld ns\n", genpd->name,
 572                                         elapsed_ns);
 573                 }
 574         }
 575
 576         genpd->status = GPD_STATE_POWER_OFF;
 577
 578         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 579                 genpd_sd_counter_dec(link->master);
 580                 genpd_queue_power_off_work(link->master);
 581         }
 582
 583  out:
 584         genpd->poweroff_task = NULL;
 585         wake_up_all(&genpd->status_wait_queue);
 586         return ret;
 587 }
 588
 589 /**
 590  * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 591  * @work: Work structure used for scheduling the execution of this function.
 592  */
 593 static void genpd_power_off_work_fn(struct work_struct *work)
 594 {
 595         struct generic_pm_domain *genpd;
 596
 597         genpd = container_of(work, struct generic_pm_domain, power_off_work);
 598
 599         genpd_acquire_lock(genpd);
 600         pm_genpd_poweroff(genpd);
 601         genpd_release_lock(genpd);
 602 }
 603
 604 /**
 605  * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 606  * @dev: Device to suspend.
 607  *
 608  * Carry out a runtime suspend of a device under the assumption that its
 609  * pm_domain field points to the domain member of an object of type
 610  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 611  */
 612 static int pm_genpd_runtime_suspend(struct device *dev)
 613 {
 614         struct generic_pm_domain *genpd;
 615         bool (*stop_ok)(struct device *__dev);
 616         int ret;
 617
 618         dev_dbg(dev, "%s()\n", __func__);
 619
 620         genpd = dev_to_genpd(dev);
 621         if (IS_ERR(genpd))
 622                 return -EINVAL;
 623
 624         might_sleep_if(!genpd->dev_irq_safe);
 625
 626         stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
 627         if (stop_ok && !stop_ok(dev))
 628                 return -EBUSY;
 629
 630         ret = genpd_stop_dev(genpd, dev);
 631         if (ret)
 632                 return ret;
 633
 634         /*
 635          * If power.irq_safe is set, this routine will be run with interrupts
 636          * off, so it can't use mutexes.
 637          */
 638         if (dev->power.irq_safe)
 639                 return 0;
 640
 641         mutex_lock(&genpd->lock);
 642         genpd->in_progress++;
 643         pm_genpd_poweroff(genpd);
 644         genpd->in_progress--;
 645         mutex_unlock(&genpd->lock);
 646
 647         return 0;
 648 }
 649
 650 /**
 651  * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
 652  * @dev: Device to resume.
 653  *
 654  * Carry out a runtime resume of a device under the assumption that its
 655  * pm_domain field points to the domain member of an object of type
 656  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 657  */
 658 static int pm_genpd_runtime_resume(struct device *dev)
 659 {
 660         struct generic_pm_domain *genpd;
 661         DEFINE_WAIT(wait);
 662         int ret;
 663
 664         dev_dbg(dev, "%s()\n", __func__);
 665
 666         genpd = dev_to_genpd(dev);
 667         if (IS_ERR(genpd))
 668                 return -EINVAL;
 669
 670         might_sleep_if(!genpd->dev_irq_safe);
 671
 672         /* If power.irq_safe, the PM domain is never powered off. */
 673         if (dev->power.irq_safe)
 674                 return genpd_start_dev_no_timing(genpd, dev);
 675
 676         mutex_lock(&genpd->lock);
 677         ret = __pm_genpd_poweron(genpd);
 678         if (ret) {
 679                 mutex_unlock(&genpd->lock);
 680                 return ret;
 681         }
 682         genpd->status = GPD_STATE_BUSY;
 683         genpd->resume_count++;
 684         for (;;) {
 685                 prepare_to_wait(&genpd->status_wait_queue, &wait,
 686                                 TASK_UNINTERRUPTIBLE);
 687                 /*
 688                  * If current is the powering off task, we have been called
 689                  * reentrantly from one of the device callbacks, so we should
 690                  * not wait.
 691                  */
 692                 if (!genpd->poweroff_task || genpd->poweroff_task == current)
 693                         break;
 694                 mutex_unlock(&genpd->lock);
 695
 696                 schedule();
 697
 698                 mutex_lock(&genpd->lock);
 699         }
 700         finish_wait(&genpd->status_wait_queue, &wait);
 701         __pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
 702         genpd->resume_count--;
 703         genpd_set_active(genpd);
 704         wake_up_all(&genpd->status_wait_queue);
 705         mutex_unlock(&genpd->lock);
 706
 707         return 0;
 708 }
 709
 710 /**
 711  * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
 712  */
 713 void pm_genpd_poweroff_unused(void)
 714 {
 715         struct generic_pm_domain *genpd;
 716
 717         mutex_lock(&gpd_list_lock);
 718
 719         list_for_each_entry(genpd, &gpd_list, gpd_list_node)
 720                 genpd_queue_power_off_work(genpd);
 721
 722         mutex_unlock(&gpd_list_lock);
 723 }
 724
 725 #else
 726
 727 static inline int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 728                                             unsigned long val, void *ptr)
 729 {
 730         return NOTIFY_DONE;
 731 }
 732
 733 static inline void genpd_power_off_work_fn(struct work_struct *work) {}
 734
 735 #define pm_genpd_runtime_suspend        NULL
 736 #define pm_genpd_runtime_resume         NULL
 737
 738 #endif /* CONFIG_PM_RUNTIME */
 739
 740 #ifdef CONFIG_PM_SLEEP
 741
 742 /**
 743  * pm_genpd_present - Check if the given PM domain has been initialized.
 744  * @genpd: PM domain to check.
 745  */
 746 static bool pm_genpd_present(struct generic_pm_domain *genpd)
 747 {
 748         struct generic_pm_domain *gpd;
 749
 750         if (IS_ERR_OR_NULL(genpd))
 751                 return false;
 752
 753         list_for_each_entry(gpd, &gpd_list, gpd_list_node)
 754                 if (gpd == genpd)
 755                         return true;
 756
 757         return false;
 758 }
 759
 760 static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
 761                                     struct device *dev)
 762 {
 763         return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
 764 }
 765
 766 static int genpd_suspend_dev(struct generic_pm_domain *genpd, struct device *dev)
 767 {
 768         return GENPD_DEV_CALLBACK(genpd, int, suspend, dev);
 769 }
 770
 771 static int genpd_suspend_late(struct generic_pm_domain *genpd, struct device *dev)
 772 {
 773         return GENPD_DEV_CALLBACK(genpd, int, suspend_late, dev);
 774 }
 775
 776 static int genpd_resume_early(struct generic_pm_domain *genpd, struct device *dev)
 777 {
 778         return GENPD_DEV_CALLBACK(genpd, int, resume_early, dev);
 779 }
 780
 781 static int genpd_resume_dev(struct generic_pm_domain *genpd, struct device *dev)
 782 {
 783         return GENPD_DEV_CALLBACK(genpd, int, resume, dev);
 784 }
 785
 786 static int genpd_freeze_dev(struct generic_pm_domain *genpd, struct device *dev)
 787 {
 788         return GENPD_DEV_CALLBACK(genpd, int, freeze, dev);
 789 }
 790
 791 static int genpd_freeze_late(struct generic_pm_domain *genpd, struct device *dev)
 792 {
 793         return GENPD_DEV_CALLBACK(genpd, int, freeze_late, dev);
 794 }
 795
 796 static int genpd_thaw_early(struct generic_pm_domain *genpd, struct device *dev)
 797 {
 798         return GENPD_DEV_CALLBACK(genpd, int, thaw_early, dev);
 799 }
 800
 801 static int genpd_thaw_dev(struct generic_pm_domain *genpd, struct device *dev)
 802 {
 803         return GENPD_DEV_CALLBACK(genpd, int, thaw, dev);
 804 }
 805
 806 /**
 807  * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
 808  * @genpd: PM domain to power off, if possible.
 809  *
 810  * Check if the given PM domain can be powered off (during system suspend or
 811  * hibernation) and do that if so.  Also, in that case propagate to its masters.
 812  *
 813  * This function is only called in "noirq" and "syscore" stages of system power
 814  * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 815  * executed sequentially, so it is guaranteed that it will never run twice in
 816  * parallel).
 817  */
 818 static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
 819 {
 820         struct gpd_link *link;
 821
 822         if (genpd->status == GPD_STATE_POWER_OFF)
 823                 return;
 824
 825         if (genpd->suspended_count != genpd->device_count
 826             || atomic_read(&genpd->sd_count) > 0)
 827                 return;
 828
 829         if (genpd->power_off)
 830                 genpd->power_off(genpd);
 831
 832         genpd->status = GPD_STATE_POWER_OFF;
 833
 834         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 835                 genpd_sd_counter_dec(link->master);
 836                 pm_genpd_sync_poweroff(link->master);
 837         }
 838 }
 839
 840 /**
 841  * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
 842  * @genpd: PM domain to power on.
 843  *
 844  * This function is only called in "noirq" and "syscore" stages of system power
 845  * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 846  * executed sequentially, so it is guaranteed that it will never run twice in
 847  * parallel).
 848  */
 849 static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd)
 850 {
 851         struct gpd_link *link;
 852
 853         if (genpd->status != GPD_STATE_POWER_OFF)
 854                 return;
 855
 856         list_for_each_entry(link, &genpd->slave_links, slave_node) {
 857                 pm_genpd_sync_poweron(link->master);
 858                 genpd_sd_counter_inc(link->master);
 859         }
 860
 861         if (genpd->power_on)
 862                 genpd->power_on(genpd);
 863
 864         genpd->status = GPD_STATE_ACTIVE;
 865 }
 866
 867 /**
 868  * resume_needed - Check whether to resume a device before system suspend.
 869  * @dev: Device to check.
 870  * @genpd: PM domain the device belongs to.
 871  *
 872  * There are two cases in which a device that can wake up the system from sleep
 873  * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
 874  * to wake up the system and it has to remain active for this purpose while the
 875  * system is in the sleep state and (2) if the device is not enabled to wake up
 876  * the system from sleep states and it generally doesn't generate wakeup signals
 877  * by itself (those signals are generated on its behalf by other parts of the
 878  * system).  In the latter case it may be necessary to reconfigure the device's
 879  * wakeup settings during system suspend, because it may have been set up to
 880  * signal remote wakeup from the system's working state as needed by runtime PM.
 881  * Return 'true' in either of the above cases.
 882  */
 883 static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
 884 {
 885         bool active_wakeup;
 886
 887         if (!device_can_wakeup(dev))
 888                 return false;
 889
 890         active_wakeup = genpd_dev_active_wakeup(genpd, dev);
 891         return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
 892 }
 893
 894 /**
 895  * pm_genpd_prepare - Start power transition of a device in a PM domain.
 896  * @dev: Device to start the transition of.
 897  *
 898  * Start a power transition of a device (during a system-wide power transition)
 899  * under the assumption that its pm_domain field points to the domain member of
 900  * an object of type struct generic_pm_domain representing a PM domain
 901  * consisting of I/O devices.
 902  */
 903 static int pm_genpd_prepare(struct device *dev)
 904 {
 905         struct generic_pm_domain *genpd;
 906         int ret;
 907
 908         dev_dbg(dev, "%s()\n", __func__);
 909
 910         genpd = dev_to_genpd(dev);
 911         if (IS_ERR(genpd))
 912                 return -EINVAL;
 913
 914         /*
 915          * If a wakeup request is pending for the device, it should be woken up
 916          * at this point and a system wakeup event should be reported if it's
 917          * set up to wake up the system from sleep states.
 918          */
 919         pm_runtime_get_noresume(dev);
 920         if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
 921                 pm_wakeup_event(dev, 0);
 922
 923         if (pm_wakeup_pending()) {
 924                 pm_runtime_put_sync(dev);
 925                 return -EBUSY;
 926         }
 927
 928         if (resume_needed(dev, genpd))
 929                 pm_runtime_resume(dev);
 930
 931         genpd_acquire_lock(genpd);
 932
 933         if (genpd->prepared_count++ == 0) {
 934                 genpd->suspended_count = 0;
 935                 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
 936         }
 937
 938         genpd_release_lock(genpd);
 939
 940         if (genpd->suspend_power_off) {
 941                 pm_runtime_put_noidle(dev);
 942                 return 0;
 943         }
 944
 945         /*
 946          * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
 947          * so pm_genpd_poweron() will return immediately, but if the device
 948          * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
 949          * to make it operational.
 950          */
 951         pm_runtime_resume(dev);
 952         __pm_runtime_disable(dev, false);
 953
 954         ret = pm_generic_prepare(dev);
 955         if (ret) {
 956                 mutex_lock(&genpd->lock);
 957
 958                 if (--genpd->prepared_count == 0)
 959                         genpd->suspend_power_off = false;
 960
 961                 mutex_unlock(&genpd->lock);
 962                 pm_runtime_enable(dev);
 963         }
 964
 965         pm_runtime_put_sync(dev);
 966         return ret;
 967 }
 968
 969 /**
 970  * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
 971  * @dev: Device to suspend.
 972  *
 973  * Suspend a device under the assumption that its pm_domain field points to the
 974  * domain member of an object of type struct generic_pm_domain representing
 975  * a PM domain consisting of I/O devices.
 976  */
 977 static int pm_genpd_suspend(struct device *dev)
 978 {
 979         struct generic_pm_domain *genpd;
 980
 981         dev_dbg(dev, "%s()\n", __func__);
 982
 983         genpd = dev_to_genpd(dev);
 984         if (IS_ERR(genpd))
 985                 return -EINVAL;
 986
 987         return genpd->suspend_power_off ? 0 : genpd_suspend_dev(genpd, dev);
 988 }
 989
 990 /**
 991  * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
 992  * @dev: Device to suspend.
 993  *
 994  * Carry out a late suspend of a device under the assumption that its
 995  * pm_domain field points to the domain member of an object of type
 996  * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 997  */
 998 static int pm_genpd_suspend_late(struct device *dev)
 999 {
1000         struct generic_pm_domain *genpd;
1001
1002         dev_dbg(dev, "%s()\n", __func__);
1003
1004         genpd = dev_to_genpd(dev);
1005         if (IS_ERR(genpd))
1006                 return -EINVAL;
1007
1008         return genpd->suspend_power_off ? 0 : genpd_suspend_late(genpd, dev);
1009 }
1010
1011 /**
1012  * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1013  * @dev: Device to suspend.
1014  *
1015  * Stop the device and remove power from the domain if all devices in it have
1016  * been stopped.
1017  */
1018 static int pm_genpd_suspend_noirq(struct device *dev)
1019 {
1020         struct generic_pm_domain *genpd;
1021
1022         dev_dbg(dev, "%s()\n", __func__);
1023
1024         genpd = dev_to_genpd(dev);
1025         if (IS_ERR(genpd))
1026                 return -EINVAL;
1027
1028         if (genpd->suspend_power_off
1029             || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1030                 return 0;
1031
1032         genpd_stop_dev(genpd, dev);
1033
1034         /*
1035          * Since all of the "noirq" callbacks are executed sequentially, it is
1036          * guaranteed that this function will never run twice in parallel for
1037          * the same PM domain, so it is not necessary to use locking here.
1038          */
1039         genpd->suspended_count++;
1040         pm_genpd_sync_poweroff(genpd);
1041
1042         return 0;
1043 }
1044
1045 /**
1046  * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1047  * @dev: Device to resume.
1048  *
1049  * Restore power to the device's PM domain, if necessary, and start the device.
1050  */
1051 static int pm_genpd_resume_noirq(struct device *dev)
1052 {
1053         struct generic_pm_domain *genpd;
1054
1055         dev_dbg(dev, "%s()\n", __func__);
1056
1057         genpd = dev_to_genpd(dev);
1058         if (IS_ERR(genpd))
1059                 return -EINVAL;
1060
1061         if (genpd->suspend_power_off
1062             || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1063                 return 0;
1064
1065         /*
1066          * Since all of the "noirq" callbacks are executed sequentially, it is
1067          * guaranteed that this function will never run twice in parallel for
1068          * the same PM domain, so it is not necessary to use locking here.
1069          */
1070         pm_genpd_sync_poweron(genpd);
1071         genpd->suspended_count--;
1072
1073         return genpd_start_dev(genpd, dev);
1074 }
1075
1076 /**
1077  * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
1078  * @dev: Device to resume.
1079  *
1080  * Carry out an early resume of a device under the assumption that its
1081  * pm_domain field points to the domain member of an object of type
1082  * struct generic_pm_domain representing a power domain consisting of I/O
1083  * devices.
1084  */
1085 static int pm_genpd_resume_early(struct device *dev)
1086 {
1087         struct generic_pm_domain *genpd;
1088
1089         dev_dbg(dev, "%s()\n", __func__);
1090
1091         genpd = dev_to_genpd(dev);
1092         if (IS_ERR(genpd))
1093                 return -EINVAL;
1094
1095         return genpd->suspend_power_off ? 0 : genpd_resume_early(genpd, dev);
1096 }
1097
1098 /**
1099  * pm_genpd_resume - Resume of device in an I/O PM domain.
1100  * @dev: Device to resume.
1101  *
1102  * Resume a device under the assumption that its pm_domain field points to the
1103  * domain member of an object of type struct generic_pm_domain representing
1104  * a power domain consisting of I/O devices.
1105  */
1106 static int pm_genpd_resume(struct device *dev)
1107 {
1108         struct generic_pm_domain *genpd;
1109
1110         dev_dbg(dev, "%s()\n", __func__);
1111
1112         genpd = dev_to_genpd(dev);
1113         if (IS_ERR(genpd))
1114                 return -EINVAL;
1115
1116         return genpd->suspend_power_off ? 0 : genpd_resume_dev(genpd, dev);
1117 }
1118
1119 /**
1120  * pm_genpd_freeze - Freezing a device in an I/O PM domain.
1121  * @dev: Device to freeze.
1122  *
1123  * Freeze a device under the assumption that its pm_domain field points to the
1124  * domain member of an object of type struct generic_pm_domain representing
1125  * a power domain consisting of I/O devices.
1126  */
1127 static int pm_genpd_freeze(struct device *dev)
1128 {
1129         struct generic_pm_domain *genpd;
1130
1131         dev_dbg(dev, "%s()\n", __func__);
1132
1133         genpd = dev_to_genpd(dev);
1134         if (IS_ERR(genpd))
1135                 return -EINVAL;
1136
1137         return genpd->suspend_power_off ? 0 : genpd_freeze_dev(genpd, dev);
1138 }
1139
1140 /**
1141  * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
1142  * @dev: Device to freeze.
1143  *
1144  * Carry out a late freeze of a device under the assumption that its
1145  * pm_domain field points to the domain member of an object of type
1146  * struct generic_pm_domain representing a power domain consisting of I/O
1147  * devices.
1148  */
1149 static int pm_genpd_freeze_late(struct device *dev)
1150 {
1151         struct generic_pm_domain *genpd;
1152
1153         dev_dbg(dev, "%s()\n", __func__);
1154
1155         genpd = dev_to_genpd(dev);
1156         if (IS_ERR(genpd))
1157                 return -EINVAL;
1158
1159         return genpd->suspend_power_off ? 0 : genpd_freeze_late(genpd, dev);
1160 }
1161
1162 /**
1163  * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1164  * @dev: Device to freeze.
1165  *
1166  * Carry out a late freeze of a device under the assumption that its
1167  * pm_domain field points to the domain member of an object of type
1168  * struct generic_pm_domain representing a power domain consisting of I/O
1169  * devices.
1170  */
1171 static int pm_genpd_freeze_noirq(struct device *dev)
1172 {
1173         struct generic_pm_domain *genpd;
1174
1175         dev_dbg(dev, "%s()\n", __func__);
1176
1177         genpd = dev_to_genpd(dev);
1178         if (IS_ERR(genpd))
1179                 return -EINVAL;
1180
1181         return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
1182 }
1183
1184 /**
1185  * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1186  * @dev: Device to thaw.
1187  *
1188  * Start the device, unless power has been removed from the domain already
1189  * before the system transition.
1190  */
1191 static int pm_genpd_thaw_noirq(struct device *dev)
1192 {
1193         struct generic_pm_domain *genpd;
1194
1195         dev_dbg(dev, "%s()\n", __func__);
1196
1197         genpd = dev_to_genpd(dev);
1198         if (IS_ERR(genpd))
1199                 return -EINVAL;
1200
1201         return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
1202 }
1203
1204 /**
1205  * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
1206  * @dev: Device to thaw.
1207  *
1208  * Carry out an early thaw of a device under the assumption that its
1209  * pm_domain field points to the domain member of an object of type
1210  * struct generic_pm_domain representing a power domain consisting of I/O
1211  * devices.
1212  */
1213 static int pm_genpd_thaw_early(struct device *dev)
1214 {
1215         struct generic_pm_domain *genpd;
1216
1217         dev_dbg(dev, "%s()\n", __func__);
1218
1219         genpd = dev_to_genpd(dev);
1220         if (IS_ERR(genpd))
1221                 return -EINVAL;
1222
1223         return genpd->suspend_power_off ? 0 : genpd_thaw_early(genpd, dev);
1224 }
1225
1226 /**
1227  * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1228  * @dev: Device to thaw.
1229  *
1230  * Thaw a device under the assumption that its pm_domain field points to the
1231  * domain member of an object of type struct generic_pm_domain representing
1232  * a power domain consisting of I/O devices.
1233  */
1234 static int pm_genpd_thaw(struct device *dev)
1235 {
1236         struct generic_pm_domain *genpd;
1237
1238         dev_dbg(dev, "%s()\n", __func__);
1239
1240         genpd = dev_to_genpd(dev);
1241         if (IS_ERR(genpd))
1242                 return -EINVAL;
1243
1244         return genpd->suspend_power_off ? 0 : genpd_thaw_dev(genpd, dev);
1245 }
1246
1247 /**
1248  * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1249  * @dev: Device to resume.
1250  *
1251  * Make sure the domain will be in the same power state as before the
1252  * hibernation the system is resuming from and start the device if necessary.
1253  */
1254 static int pm_genpd_restore_noirq(struct device *dev)
1255 {
1256         struct generic_pm_domain *genpd;
1257
1258         dev_dbg(dev, "%s()\n", __func__);
1259
1260         genpd = dev_to_genpd(dev);
1261         if (IS_ERR(genpd))
1262                 return -EINVAL;
1263
1264         /*
1265          * Since all of the "noirq" callbacks are executed sequentially, it is
1266          * guaranteed that this function will never run twice in parallel for
1267          * the same PM domain, so it is not necessary to use locking here.
1268          *
1269          * At this point suspended_count == 0 means we are being run for the
1270          * first time for the given domain in the present cycle.
1271          */
1272         if (genpd->suspended_count++ == 0) {
1273                 /*
1274                  * The boot kernel might put the domain into arbitrary state,
1275                  * so make it appear as powered off to pm_genpd_sync_poweron(),
1276                  * so that it tries to power it on in case it was really off.
1277                  */
1278                 genpd->status = GPD_STATE_POWER_OFF;
1279                 if (genpd->suspend_power_off) {
1280                         /*
1281                          * If the domain was off before the hibernation, make
1282                          * sure it will be off going forward.
1283                          */
1284                         if (genpd->power_off)
1285                                 genpd->power_off(genpd);
1286
1287                         return 0;
1288                 }
1289         }
1290
1291         if (genpd->suspend_power_off)
1292                 return 0;
1293
1294         pm_genpd_sync_poweron(genpd);
1295
1296         return genpd_start_dev(genpd, dev);
1297 }
1298
1299 /**
1300  * pm_genpd_complete - Complete power transition of a device in a power domain.
1301  * @dev: Device to complete the transition of.
1302  *
1303  * Complete a power transition of a device (during a system-wide power
1304  * transition) under the assumption that its pm_domain field points to the
1305  * domain member of an object of type struct generic_pm_domain representing
1306  * a power domain consisting of I/O devices.
1307  */
1308 static void pm_genpd_complete(struct device *dev)
1309 {
1310         struct generic_pm_domain *genpd;
1311         bool run_complete;
1312
1313         dev_dbg(dev, "%s()\n", __func__);
1314
1315         genpd = dev_to_genpd(dev);
1316         if (IS_ERR(genpd))
1317                 return;
1318
1319         mutex_lock(&genpd->lock);
1320
1321         run_complete = !genpd->suspend_power_off;
1322         if (--genpd->prepared_count == 0)
1323                 genpd->suspend_power_off = false;
1324
1325         mutex_unlock(&genpd->lock);
1326
1327         if (run_complete) {
1328                 pm_generic_complete(dev);
1329                 pm_runtime_set_active(dev);
1330                 pm_runtime_enable(dev);
1331                 pm_runtime_idle(dev);
1332         }
1333 }
1334
1335 /**
1336  * pm_genpd_syscore_switch - Switch power during system core suspend or resume.
1337  * @dev: Device that normally is marked as "always on" to switch power for.
1338  *
1339  * This routine may only be called during the system core (syscore) suspend or
1340  * resume phase for devices whose "always on" flags are set.
1341  */
1342 void pm_genpd_syscore_switch(struct device *dev, bool suspend)
1343 {
1344         struct generic_pm_domain *genpd;
1345
1346         genpd = dev_to_genpd(dev);
1347         if (!pm_genpd_present(genpd))
1348                 return;
1349
1350         if (suspend) {
1351                 genpd->suspended_count++;
1352                 pm_genpd_sync_poweroff(genpd);
1353         } else {
1354                 pm_genpd_sync_poweron(genpd);
1355                 genpd->suspended_count--;
1356         }
1357 }
1358 EXPORT_SYMBOL_GPL(pm_genpd_syscore_switch);
1359
1360 #else
1361
1362 #define pm_genpd_prepare                NULL
1363 #define pm_genpd_suspend                NULL
1364 #define pm_genpd_suspend_late           NULL
1365 #define pm_genpd_suspend_noirq          NULL
1366 #define pm_genpd_resume_early           NULL
1367 #define pm_genpd_resume_noirq           NULL
1368 #define pm_genpd_resume                 NULL
1369 #define pm_genpd_freeze                 NULL
1370 #define pm_genpd_freeze_late            NULL
1371 #define pm_genpd_freeze_noirq           NULL
1372 #define pm_genpd_thaw_early             NULL
1373 #define pm_genpd_thaw_noirq             NULL
1374 #define pm_genpd_thaw                   NULL
1375 #define pm_genpd_restore_noirq          NULL
1376 #define pm_genpd_complete               NULL
1377
1378 #endif /* CONFIG_PM_SLEEP */
1379
1380 static struct generic_pm_domain_data *__pm_genpd_alloc_dev_data(struct device *dev)
1381 {
1382         struct generic_pm_domain_data *gpd_data;
1383
1384         gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1385         if (!gpd_data)
1386                 return NULL;
1387
1388         mutex_init(&gpd_data->lock);
1389         gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1390         dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1391         return gpd_data;
1392 }
1393
1394 static void __pm_genpd_free_dev_data(struct device *dev,
1395                                      struct generic_pm_domain_data *gpd_data)
1396 {
1397         dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1398         kfree(gpd_data);
1399 }
1400
1401 /**
1402  * __pm_genpd_add_device - Add a device to an I/O PM domain.
1403  * @genpd: PM domain to add the device to.
1404  * @dev: Device to be added.
1405  * @td: Set of PM QoS timing parameters to attach to the device.
1406  */
1407 int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1408                           struct gpd_timing_data *td)
1409 {
1410         struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1411         struct pm_domain_data *pdd;
1412         int ret = 0;
1413
1414         dev_dbg(dev, "%s()\n", __func__);
1415
1416         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1417                 return -EINVAL;
1418
1419         gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1420         if (!gpd_data_new)
1421                 return -ENOMEM;
1422
1423         genpd_acquire_lock(genpd);
1424
1425         if (genpd->prepared_count > 0) {
1426                 ret = -EAGAIN;
1427                 goto out;
1428         }
1429
1430         list_for_each_entry(pdd, &genpd->dev_list, list_node)
1431                 if (pdd->dev == dev) {
1432                         ret = -EINVAL;
1433                         goto out;
1434                 }
1435
1436         ret = dev_pm_get_subsys_data(dev);
1437         if (ret)
1438                 goto out;
1439
1440         genpd->device_count++;
1441         genpd->max_off_time_changed = true;
1442
1443         spin_lock_irq(&dev->power.lock);
1444
1445         dev->pm_domain = &genpd->domain;
1446         if (dev->power.subsys_data->domain_data) {
1447                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1448         } else {
1449                 gpd_data = gpd_data_new;
1450                 dev->power.subsys_data->domain_data = &gpd_data->base;
1451         }
1452         gpd_data->refcount++;
1453         if (td)
1454                 gpd_data->td = *td;
1455
1456         spin_unlock_irq(&dev->power.lock);
1457
1458         mutex_lock(&gpd_data->lock);
1459         gpd_data->base.dev = dev;
1460         list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1461         gpd_data->need_restore = genpd->status == GPD_STATE_POWER_OFF;
1462         gpd_data->td.constraint_changed = true;
1463         gpd_data->td.effective_constraint_ns = -1;
1464         mutex_unlock(&gpd_data->lock);
1465
1466  out:
1467         genpd_release_lock(genpd);
1468
1469         if (gpd_data != gpd_data_new)
1470                 __pm_genpd_free_dev_data(dev, gpd_data_new);
1471
1472         return ret;
1473 }
1474
1475 /**
1476  * __pm_genpd_of_add_device - Add a device to an I/O PM domain.
1477  * @genpd_node: Device tree node pointer representing a PM domain to which the
1478  *   the device is added to.
1479  * @dev: Device to be added.
1480  * @td: Set of PM QoS timing parameters to attach to the device.
1481  */
1482 int __pm_genpd_of_add_device(struct device_node *genpd_node, struct device *dev,
1483                              struct gpd_timing_data *td)
1484 {
1485         struct generic_pm_domain *genpd = NULL, *gpd;
1486
1487         dev_dbg(dev, "%s()\n", __func__);
1488
1489         if (IS_ERR_OR_NULL(genpd_node) || IS_ERR_OR_NULL(dev))
1490                 return -EINVAL;
1491
1492         mutex_lock(&gpd_list_lock);
1493         list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1494                 if (gpd->of_node == genpd_node) {
1495                         genpd = gpd;
1496                         break;
1497                 }
1498         }
1499         mutex_unlock(&gpd_list_lock);
1500
1501         if (!genpd)
1502                 return -EINVAL;
1503
1504         return __pm_genpd_add_device(genpd, dev, td);
1505 }
1506
1507
1508 /**
1509  * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
1510  * @domain_name: Name of the PM domain to add the device to.
1511  * @dev: Device to be added.
1512  * @td: Set of PM QoS timing parameters to attach to the device.
1513  */
1514 int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
1515                                struct gpd_timing_data *td)
1516 {
1517         return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
1518 }
1519
1520 /**
1521  * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1522  * @genpd: PM domain to remove the device from.
1523  * @dev: Device to be removed.
1524  */
1525 int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1526                            struct device *dev)
1527 {
1528         struct generic_pm_domain_data *gpd_data;
1529         struct pm_domain_data *pdd;
1530         bool remove = false;
1531         int ret = 0;
1532
1533         dev_dbg(dev, "%s()\n", __func__);
1534
1535         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)
1536             ||  IS_ERR_OR_NULL(dev->pm_domain)
1537             ||  pd_to_genpd(dev->pm_domain) != genpd)
1538                 return -EINVAL;
1539
1540         genpd_acquire_lock(genpd);
1541
1542         if (genpd->prepared_count > 0) {
1543                 ret = -EAGAIN;
1544                 goto out;
1545         }
1546
1547         genpd->device_count--;
1548         genpd->max_off_time_changed = true;
1549
1550         spin_lock_irq(&dev->power.lock);
1551
1552         dev->pm_domain = NULL;
1553         pdd = dev->power.subsys_data->domain_data;
1554         list_del_init(&pdd->list_node);
1555         gpd_data = to_gpd_data(pdd);
1556         if (--gpd_data->refcount == 0) {
1557                 dev->power.subsys_data->domain_data = NULL;
1558                 remove = true;
1559         }
1560
1561         spin_unlock_irq(&dev->power.lock);
1562
1563         mutex_lock(&gpd_data->lock);
1564         pdd->dev = NULL;
1565         mutex_unlock(&gpd_data->lock);
1566
1567         genpd_release_lock(genpd);
1568
1569         dev_pm_put_subsys_data(dev);
1570         if (remove)
1571                 __pm_genpd_free_dev_data(dev, gpd_data);
1572
1573         return 0;
1574
1575  out:
1576         genpd_release_lock(genpd);
1577
1578         return ret;
1579 }
1580
1581 /**
1582  * pm_genpd_dev_need_restore - Set/unset the device's "need restore" flag.
1583  * @dev: Device to set/unset the flag for.
1584  * @val: The new value of the device's "need restore" flag.
1585  */
1586 void pm_genpd_dev_need_restore(struct device *dev, bool val)
1587 {
1588         struct pm_subsys_data *psd;
1589         unsigned long flags;
1590
1591         spin_lock_irqsave(&dev->power.lock, flags);
1592
1593         psd = dev_to_psd(dev);
1594         if (psd && psd->domain_data)
1595                 to_gpd_data(psd->domain_data)->need_restore = val;
1596
1597         spin_unlock_irqrestore(&dev->power.lock, flags);
1598 }
1599 EXPORT_SYMBOL_GPL(pm_genpd_dev_need_restore);
1600
1601 /**
1602  * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1603  * @genpd: Master PM domain to add the subdomain to.
1604  * @subdomain: Subdomain to be added.
1605  */
1606 int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1607                            struct generic_pm_domain *subdomain)
1608 {
1609         struct gpd_link *link;
1610         int ret = 0;
1611
1612         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1613             || genpd == subdomain)
1614                 return -EINVAL;
1615
1616  start:
1617         genpd_acquire_lock(genpd);
1618         mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1619
1620         if (subdomain->status != GPD_STATE_POWER_OFF
1621             && subdomain->status != GPD_STATE_ACTIVE) {
1622                 mutex_unlock(&subdomain->lock);
1623                 genpd_release_lock(genpd);
1624                 goto start;
1625         }
1626
1627         if (genpd->status == GPD_STATE_POWER_OFF
1628             &&  subdomain->status != GPD_STATE_POWER_OFF) {
1629                 ret = -EINVAL;
1630                 goto out;
1631         }
1632
1633         list_for_each_entry(link, &genpd->master_links, master_node) {
1634                 if (link->slave == subdomain && link->master == genpd) {
1635                         ret = -EINVAL;
1636                         goto out;
1637                 }
1638         }
1639
1640         link = kzalloc(sizeof(*link), GFP_KERNEL);
1641         if (!link) {
1642                 ret = -ENOMEM;
1643                 goto out;
1644         }
1645         link->master = genpd;
1646         list_add_tail(&link->master_node, &genpd->master_links);
1647         link->slave = subdomain;
1648         list_add_tail(&link->slave_node, &subdomain->slave_links);
1649         if (subdomain->status != GPD_STATE_POWER_OFF)
1650                 genpd_sd_counter_inc(genpd);
1651
1652  out:
1653         mutex_unlock(&subdomain->lock);
1654         genpd_release_lock(genpd);
1655
1656         return ret;
1657 }
1658
1659 /**
1660  * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
1661  * @master_name: Name of the master PM domain to add the subdomain to.
1662  * @subdomain_name: Name of the subdomain to be added.
1663  */
1664 int pm_genpd_add_subdomain_names(const char *master_name,
1665                                  const char *subdomain_name)
1666 {
1667         struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
1668
1669         if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
1670                 return -EINVAL;
1671
1672         mutex_lock(&gpd_list_lock);
1673         list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1674                 if (!master && !strcmp(gpd->name, master_name))
1675                         master = gpd;
1676
1677                 if (!subdomain && !strcmp(gpd->name, subdomain_name))
1678                         subdomain = gpd;
1679
1680                 if (master && subdomain)
1681                         break;
1682         }
1683         mutex_unlock(&gpd_list_lock);
1684
1685         return pm_genpd_add_subdomain(master, subdomain);
1686 }
1687
1688 /**
1689  * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1690  * @genpd: Master PM domain to remove the subdomain from.
1691  * @subdomain: Subdomain to be removed.
1692  */
1693 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1694                               struct generic_pm_domain *subdomain)
1695 {
1696         struct gpd_link *link;
1697         int ret = -EINVAL;
1698
1699         if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1700                 return -EINVAL;
1701
1702  start:
1703         genpd_acquire_lock(genpd);
1704
1705         list_for_each_entry(link, &genpd->master_links, master_node) {
1706                 if (link->slave != subdomain)
1707                         continue;
1708
1709                 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1710
1711                 if (subdomain->status != GPD_STATE_POWER_OFF
1712                     && subdomain->status != GPD_STATE_ACTIVE) {
1713                         mutex_unlock(&subdomain->lock);
1714                         genpd_release_lock(genpd);
1715                         goto start;
1716                 }
1717
1718                 list_del(&link->master_node);
1719                 list_del(&link->slave_node);
1720                 kfree(link);
1721                 if (subdomain->status != GPD_STATE_POWER_OFF)
1722                         genpd_sd_counter_dec(genpd);
1723
1724                 mutex_unlock(&subdomain->lock);
1725
1726                 ret = 0;
1727                 break;
1728         }
1729
1730         genpd_release_lock(genpd);
1731
1732         return ret;
1733 }
1734
1735 /**
1736  * pm_genpd_add_callbacks - Add PM domain callbacks to a given device.
1737  * @dev: Device to add the callbacks to.
1738  * @ops: Set of callbacks to add.
1739  * @td: Timing data to add to the device along with the callbacks (optional).
1740  *
1741  * Every call to this routine should be balanced with a call to
1742  * __pm_genpd_remove_callbacks() and they must not be nested.
1743  */
1744 int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops,
1745                            struct gpd_timing_data *td)
1746 {
1747         struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1748         int ret = 0;
1749
1750         if (!(dev && ops))
1751                 return -EINVAL;
1752
1753         gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1754         if (!gpd_data_new)
1755                 return -ENOMEM;
1756
1757         pm_runtime_disable(dev);
1758         device_pm_lock();
1759
1760         ret = dev_pm_get_subsys_data(dev);
1761         if (ret)
1762                 goto out;
1763
1764         spin_lock_irq(&dev->power.lock);
1765
1766         if (dev->power.subsys_data->domain_data) {
1767                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1768         } else {
1769                 gpd_data = gpd_data_new;
1770                 dev->power.subsys_data->domain_data = &gpd_data->base;
1771         }
1772         gpd_data->refcount++;
1773         gpd_data->ops = *ops;
1774         if (td)
1775                 gpd_data->td = *td;
1776
1777         spin_unlock_irq(&dev->power.lock);
1778
1779  out:
1780         device_pm_unlock();
1781         pm_runtime_enable(dev);
1782
1783         if (gpd_data != gpd_data_new)
1784                 __pm_genpd_free_dev_data(dev, gpd_data_new);
1785
1786         return ret;
1787 }
1788 EXPORT_SYMBOL_GPL(pm_genpd_add_callbacks);
1789
1790 /**
1791  * __pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device.
1792  * @dev: Device to remove the callbacks from.
1793  * @clear_td: If set, clear the device's timing data too.
1794  *
1795  * This routine can only be called after pm_genpd_add_callbacks().
1796  */
1797 int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td)
1798 {
1799         struct generic_pm_domain_data *gpd_data = NULL;
1800         bool remove = false;
1801         int ret = 0;
1802
1803         if (!(dev && dev->power.subsys_data))
1804                 return -EINVAL;
1805
1806         pm_runtime_disable(dev);
1807         device_pm_lock();
1808
1809         spin_lock_irq(&dev->power.lock);
1810
1811         if (dev->power.subsys_data->domain_data) {
1812                 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1813                 gpd_data->ops = (struct gpd_dev_ops){ NULL };
1814                 if (clear_td)
1815                         gpd_data->td = (struct gpd_timing_data){ 0 };
1816
1817                 if (--gpd_data->refcount == 0) {
1818                         dev->power.subsys_data->domain_data = NULL;
1819                         remove = true;
1820                 }
1821         } else {
1822                 ret = -EINVAL;
1823         }
1824
1825         spin_unlock_irq(&dev->power.lock);
1826
1827         device_pm_unlock();
1828         pm_runtime_enable(dev);
1829
1830         if (ret)
1831                 return ret;
1832
1833         dev_pm_put_subsys_data(dev);
1834         if (remove)
1835                 __pm_genpd_free_dev_data(dev, gpd_data);
1836
1837         return 0;
1838 }
1839 EXPORT_SYMBOL_GPL(__pm_genpd_remove_callbacks);
1840
1841 /**
1842  * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
1843  * @genpd: PM domain to be connected with cpuidle.
1844  * @state: cpuidle state this domain can disable/enable.
1845  *
1846  * Make a PM domain behave as though it contained a CPU core, that is, instead
1847  * of calling its power down routine it will enable the given cpuidle state so
1848  * that the cpuidle subsystem can power it down (if possible and desirable).
1849  */
1850 int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
1851 {
1852         struct cpuidle_driver *cpuidle_drv;
1853         struct gpd_cpu_data *cpu_data;
1854         struct cpuidle_state *idle_state;
1855         int ret = 0;
1856
1857         if (IS_ERR_OR_NULL(genpd) || state < 0)
1858                 return -EINVAL;
1859
1860         genpd_acquire_lock(genpd);
1861
1862         if (genpd->cpu_data) {
1863                 ret = -EEXIST;
1864                 goto out;
1865         }
1866         cpu_data = kzalloc(sizeof(*cpu_data), GFP_KERNEL);
1867         if (!cpu_data) {
1868                 ret = -ENOMEM;
1869                 goto out;
1870         }
1871         cpuidle_drv = cpuidle_driver_ref();
1872         if (!cpuidle_drv) {
1873                 ret = -ENODEV;
1874                 goto err_drv;
1875         }
1876         if (cpuidle_drv->state_count <= state) {
1877                 ret = -EINVAL;
1878                 goto err;
1879         }
1880         idle_state = &cpuidle_drv->states[state];
1881         if (!idle_state->disabled) {
1882                 ret = -EAGAIN;
1883                 goto err;
1884         }
1885         cpu_data->idle_state = idle_state;
1886         cpu_data->saved_exit_latency = idle_state->exit_latency;
1887         genpd->cpu_data = cpu_data;
1888         genpd_recalc_cpu_exit_latency(genpd);
1889
1890  out:
1891         genpd_release_lock(genpd);
1892         return ret;
1893
1894  err:
1895         cpuidle_driver_unref();
1896
1897  err_drv:
1898         kfree(cpu_data);
1899         goto out;
1900 }
1901
1902 /**
1903  * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
1904  * @name: Name of the domain to connect to cpuidle.
1905  * @state: cpuidle state this domain can manipulate.
1906  */
1907 int pm_genpd_name_attach_cpuidle(const char *name, int state)
1908 {
1909         return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
1910 }
1911
1912 /**
1913  * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
1914  * @genpd: PM domain to remove the cpuidle connection from.
1915  *
1916  * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
1917  * given PM domain.
1918  */
1919 int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
1920 {
1921         struct gpd_cpu_data *cpu_data;
1922         struct cpuidle_state *idle_state;
1923         int ret = 0;
1924
1925         if (IS_ERR_OR_NULL(genpd))
1926                 return -EINVAL;
1927
1928         genpd_acquire_lock(genpd);
1929
1930         cpu_data = genpd->cpu_data;
1931         if (!cpu_data) {
1932                 ret = -ENODEV;
1933                 goto out;
1934         }
1935         idle_state = cpu_data->idle_state;
1936         if (!idle_state->disabled) {
1937                 ret = -EAGAIN;
1938                 goto out;
1939         }
1940         idle_state->exit_latency = cpu_data->saved_exit_latency;
1941         cpuidle_driver_unref();
1942         genpd->cpu_data = NULL;
1943         kfree(cpu_data);
1944
1945  out:
1946         genpd_release_lock(genpd);
1947         return ret;
1948 }
1949
1950 /**
1951  * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
1952  * @name: Name of the domain to disconnect cpuidle from.
1953  */
1954 int pm_genpd_name_detach_cpuidle(const char *name)
1955 {
1956         return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
1957 }
1958
1959 /* Default device callbacks for generic PM domains. */
1960
1961 /**
1962  * pm_genpd_default_save_state - Default "save device state" for PM domians.
1963  * @dev: Device to handle.
1964  */
1965 static int pm_genpd_default_save_state(struct device *dev)
1966 {
1967         int (*cb)(struct device *__dev);
1968
1969         cb = dev_gpd_data(dev)->ops.save_state;
1970         if (cb)
1971                 return cb(dev);
1972
1973         if (dev->type && dev->type->pm)
1974                 cb = dev->type->pm->runtime_suspend;
1975         else if (dev->class && dev->class->pm)
1976                 cb = dev->class->pm->runtime_suspend;
1977         else if (dev->bus && dev->bus->pm)
1978                 cb = dev->bus->pm->runtime_suspend;
1979         else
1980                 cb = NULL;
1981
1982         if (!cb && dev->driver && dev->driver->pm)
1983                 cb = dev->driver->pm->runtime_suspend;
1984
1985         return cb ? cb(dev) : 0;
1986 }
1987
1988 /**
1989  * pm_genpd_default_restore_state - Default PM domians "restore device state".
1990  * @dev: Device to handle.
1991  */
1992 static int pm_genpd_default_restore_state(struct device *dev)
1993 {
1994         int (*cb)(struct device *__dev);
1995
1996         cb = dev_gpd_data(dev)->ops.restore_state;
1997         if (cb)
1998                 return cb(dev);
1999
2000         if (dev->type && dev->type->pm)
2001                 cb = dev->type->pm->runtime_resume;
2002         else if (dev->class && dev->class->pm)
2003                 cb = dev->class->pm->runtime_resume;
2004         else if (dev->bus && dev->bus->pm)
2005                 cb = dev->bus->pm->runtime_resume;
2006         else
2007                 cb = NULL;
2008
2009         if (!cb && dev->driver && dev->driver->pm)
2010                 cb = dev->driver->pm->runtime_resume;
2011
2012         return cb ? cb(dev) : 0;
2013 }
2014
2015 #ifdef CONFIG_PM_SLEEP
2016
2017 /**
2018  * pm_genpd_default_suspend - Default "device suspend" for PM domians.
2019  * @dev: Device to handle.
2020  */
2021 static int pm_genpd_default_suspend(struct device *dev)
2022 {
2023         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend;
2024
2025         return cb ? cb(dev) : pm_generic_suspend(dev);
2026 }
2027
2028 /**
2029  * pm_genpd_default_suspend_late - Default "late device suspend" for PM domians.
2030  * @dev: Device to handle.
2031  */
2032 static int pm_genpd_default_suspend_late(struct device *dev)
2033 {
2034         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend_late;
2035
2036         return cb ? cb(dev) : pm_generic_suspend_late(dev);
2037 }
2038
2039 /**
2040  * pm_genpd_default_resume_early - Default "early device resume" for PM domians.
2041  * @dev: Device to handle.
2042  */
2043 static int pm_genpd_default_resume_early(struct device *dev)
2044 {
2045         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume_early;
2046
2047         return cb ? cb(dev) : pm_generic_resume_early(dev);
2048 }
2049
2050 /**
2051  * pm_genpd_default_resume - Default "device resume" for PM domians.
2052  * @dev: Device to handle.
2053  */
2054 static int pm_genpd_default_resume(struct device *dev)
2055 {
2056         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume;
2057
2058         return cb ? cb(dev) : pm_generic_resume(dev);
2059 }
2060
2061 /**
2062  * pm_genpd_default_freeze - Default "device freeze" for PM domians.
2063  * @dev: Device to handle.
2064  */
2065 static int pm_genpd_default_freeze(struct device *dev)
2066 {
2067         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze;
2068
2069         return cb ? cb(dev) : pm_generic_freeze(dev);
2070 }
2071
2072 /**
2073  * pm_genpd_default_freeze_late - Default "late device freeze" for PM domians.
2074  * @dev: Device to handle.
2075  */
2076 static int pm_genpd_default_freeze_late(struct device *dev)
2077 {
2078         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late;
2079
2080         return cb ? cb(dev) : pm_generic_freeze_late(dev);
2081 }
2082
2083 /**
2084  * pm_genpd_default_thaw_early - Default "early device thaw" for PM domians.
2085  * @dev: Device to handle.
2086  */
2087 static int pm_genpd_default_thaw_early(struct device *dev)
2088 {
2089         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early;
2090
2091         return cb ? cb(dev) : pm_generic_thaw_early(dev);
2092 }
2093
2094 /**
2095  * pm_genpd_default_thaw - Default "device thaw" for PM domians.
2096  * @dev: Device to handle.
2097  */
2098 static int pm_genpd_default_thaw(struct device *dev)
2099 {
2100         int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw;
2101
2102         return cb ? cb(dev) : pm_generic_thaw(dev);
2103 }
2104
2105 #else /* !CONFIG_PM_SLEEP */
2106
2107 #define pm_genpd_default_suspend        NULL
2108 #define pm_genpd_default_suspend_late   NULL
2109 #define pm_genpd_default_resume_early   NULL
2110 #define pm_genpd_default_resume         NULL
2111 #define pm_genpd_default_freeze         NULL
2112 #define pm_genpd_default_freeze_late    NULL
2113 #define pm_genpd_default_thaw_early     NULL
2114 #define pm_genpd_default_thaw           NULL
2115
2116 #endif /* !CONFIG_PM_SLEEP */
2117
2118 /**
2119  * pm_genpd_init - Initialize a generic I/O PM domain object.
2120  * @genpd: PM domain object to initialize.
2121  * @gov: PM domain governor to associate with the domain (may be NULL).
2122  * @is_off: Initial value of the domain's power_is_off field.
2123  */
2124 void pm_genpd_init(struct generic_pm_domain *genpd,
2125                    struct dev_power_governor *gov, bool is_off)
2126 {
2127         if (IS_ERR_OR_NULL(genpd))
2128                 return;
2129
2130         INIT_LIST_HEAD(&genpd->master_links);
2131         INIT_LIST_HEAD(&genpd->slave_links);
2132         INIT_LIST_HEAD(&genpd->dev_list);
2133         mutex_init(&genpd->lock);
2134         genpd->gov = gov;
2135         INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2136         genpd->in_progress = 0;
2137         atomic_set(&genpd->sd_count, 0);
2138         genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
2139         init_waitqueue_head(&genpd->status_wait_queue);
2140         genpd->poweroff_task = NULL;
2141         genpd->resume_count = 0;
2142         genpd->device_count = 0;
2143         genpd->max_off_time_ns = -1;
2144         genpd->max_off_time_changed = true;
2145         genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
2146         genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
2147         genpd->domain.ops.runtime_idle = pm_generic_runtime_idle;
2148         genpd->domain.ops.prepare = pm_genpd_prepare;
2149         genpd->domain.ops.suspend = pm_genpd_suspend;
2150         genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
2151         genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
2152         genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
2153         genpd->domain.ops.resume_early = pm_genpd_resume_early;
2154         genpd->domain.ops.resume = pm_genpd_resume;
2155         genpd->domain.ops.freeze = pm_genpd_freeze;
2156         genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
2157         genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
2158         genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
2159         genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
2160         genpd->domain.ops.thaw = pm_genpd_thaw;
2161         genpd->domain.ops.poweroff = pm_genpd_suspend;
2162         genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
2163         genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
2164         genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
2165         genpd->domain.ops.restore_early = pm_genpd_resume_early;
2166         genpd->domain.ops.restore = pm_genpd_resume;
2167         genpd->domain.ops.complete = pm_genpd_complete;
2168         genpd->dev_ops.save_state = pm_genpd_default_save_state;
2169         genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
2170         genpd->dev_ops.suspend = pm_genpd_default_suspend;
2171         genpd->dev_ops.suspend_late = pm_genpd_default_suspend_late;
2172         genpd->dev_ops.resume_early = pm_genpd_default_resume_early;
2173         genpd->dev_ops.resume = pm_genpd_default_resume;
2174         genpd->dev_ops.freeze = pm_genpd_default_freeze;
2175         genpd->dev_ops.freeze_late = pm_genpd_default_freeze_late;
2176         genpd->dev_ops.thaw_early = pm_genpd_default_thaw_early;
2177         genpd->dev_ops.thaw = pm_genpd_default_thaw;
2178         mutex_lock(&gpd_list_lock);
2179         list_add(&genpd->gpd_list_node, &gpd_list);
2180         mutex_unlock(&gpd_list_lock);
2181 }