Linux Audio

Check our new training course

Loading...
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * drivers/base/power/domain.c - Common code related to device power domains.
   4 *
   5 * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
 
 
   6 */
   7#define pr_fmt(fmt) "PM: " fmt
   8
   9#include <linux/delay.h>
  10#include <linux/kernel.h>
  11#include <linux/io.h>
  12#include <linux/platform_device.h>
  13#include <linux/pm_opp.h>
  14#include <linux/pm_runtime.h>
  15#include <linux/pm_domain.h>
  16#include <linux/pm_qos.h>
  17#include <linux/pm_clock.h>
  18#include <linux/slab.h>
  19#include <linux/err.h>
  20#include <linux/sched.h>
  21#include <linux/suspend.h>
  22#include <linux/export.h>
  23#include <linux/cpu.h>
  24
  25#include "power.h"
  26
  27#define GENPD_RETRY_MAX_MS	250		/* Approximate */
  28
  29#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)		\
  30({								\
  31	type (*__routine)(struct device *__d); 			\
  32	type __ret = (type)0;					\
  33								\
  34	__routine = genpd->dev_ops.callback; 			\
  35	if (__routine) {					\
  36		__ret = __routine(dev); 			\
  37	}							\
  38	__ret;							\
  39})
  40
  41static LIST_HEAD(gpd_list);
  42static DEFINE_MUTEX(gpd_list_lock);
  43
  44struct genpd_lock_ops {
  45	void (*lock)(struct generic_pm_domain *genpd);
  46	void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
  47	int (*lock_interruptible)(struct generic_pm_domain *genpd);
  48	void (*unlock)(struct generic_pm_domain *genpd);
  49};
  50
  51static void genpd_lock_mtx(struct generic_pm_domain *genpd)
  52{
  53	mutex_lock(&genpd->mlock);
  54}
  55
  56static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
  57					int depth)
  58{
  59	mutex_lock_nested(&genpd->mlock, depth);
  60}
  61
  62static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
  63{
  64	return mutex_lock_interruptible(&genpd->mlock);
  65}
  66
  67static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
  68{
  69	return mutex_unlock(&genpd->mlock);
  70}
  71
  72static const struct genpd_lock_ops genpd_mtx_ops = {
  73	.lock = genpd_lock_mtx,
  74	.lock_nested = genpd_lock_nested_mtx,
  75	.lock_interruptible = genpd_lock_interruptible_mtx,
  76	.unlock = genpd_unlock_mtx,
  77};
  78
  79static void genpd_lock_spin(struct generic_pm_domain *genpd)
  80	__acquires(&genpd->slock)
  81{
  82	unsigned long flags;
  83
  84	spin_lock_irqsave(&genpd->slock, flags);
  85	genpd->lock_flags = flags;
  86}
  87
  88static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
  89					int depth)
  90	__acquires(&genpd->slock)
  91{
  92	unsigned long flags;
  93
  94	spin_lock_irqsave_nested(&genpd->slock, flags, depth);
  95	genpd->lock_flags = flags;
  96}
  97
  98static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
  99	__acquires(&genpd->slock)
 100{
 101	unsigned long flags;
 102
 103	spin_lock_irqsave(&genpd->slock, flags);
 104	genpd->lock_flags = flags;
 105	return 0;
 106}
 107
 108static void genpd_unlock_spin(struct generic_pm_domain *genpd)
 109	__releases(&genpd->slock)
 110{
 111	spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
 112}
 113
 114static const struct genpd_lock_ops genpd_spin_ops = {
 115	.lock = genpd_lock_spin,
 116	.lock_nested = genpd_lock_nested_spin,
 117	.lock_interruptible = genpd_lock_interruptible_spin,
 118	.unlock = genpd_unlock_spin,
 119};
 120
 121#define genpd_lock(p)			p->lock_ops->lock(p)
 122#define genpd_lock_nested(p, d)		p->lock_ops->lock_nested(p, d)
 123#define genpd_lock_interruptible(p)	p->lock_ops->lock_interruptible(p)
 124#define genpd_unlock(p)			p->lock_ops->unlock(p)
 125
 126#define genpd_status_on(genpd)		(genpd->status == GPD_STATE_ACTIVE)
 127#define genpd_is_irq_safe(genpd)	(genpd->flags & GENPD_FLAG_IRQ_SAFE)
 128#define genpd_is_always_on(genpd)	(genpd->flags & GENPD_FLAG_ALWAYS_ON)
 129#define genpd_is_active_wakeup(genpd)	(genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
 130#define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
 131#define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
 132
 133static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev,
 134		const struct generic_pm_domain *genpd)
 135{
 136	bool ret;
 137
 138	ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
 139
 140	/*
 141	 * Warn once if an IRQ safe device is attached to a no sleep domain, as
 142	 * to indicate a suboptimal configuration for PM. For an always on
 143	 * domain this isn't case, thus don't warn.
 144	 */
 145	if (ret && !genpd_is_always_on(genpd))
 146		dev_warn_once(dev, "PM domain %s will not be powered off\n",
 147				genpd->name);
 148
 149	return ret;
 150}
 151
 152static int genpd_runtime_suspend(struct device *dev);
 153
 154/*
 155 * Get the generic PM domain for a particular struct device.
 156 * This validates the struct device pointer, the PM domain pointer,
 157 * and checks that the PM domain pointer is a real generic PM domain.
 158 * Any failure results in NULL being returned.
 159 */
 160static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
 161{
 
 
 162	if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
 163		return NULL;
 164
 165	/* A genpd's always have its ->runtime_suspend() callback assigned. */
 166	if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
 167		return pd_to_genpd(dev->pm_domain);
 
 
 
 
 
 168
 169	return NULL;
 170}
 171
 172/*
 173 * This should only be used where we are certain that the pm_domain
 174 * attached to the device is a genpd domain.
 175 */
 176static struct generic_pm_domain *dev_to_genpd(struct device *dev)
 177{
 178	if (IS_ERR_OR_NULL(dev->pm_domain))
 179		return ERR_PTR(-EINVAL);
 180
 181	return pd_to_genpd(dev->pm_domain);
 182}
 183
 184static int genpd_stop_dev(const struct generic_pm_domain *genpd,
 185			  struct device *dev)
 186{
 187	return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
 188}
 189
 190static int genpd_start_dev(const struct generic_pm_domain *genpd,
 191			   struct device *dev)
 192{
 193	return GENPD_DEV_CALLBACK(genpd, int, start, dev);
 194}
 195
 196static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
 197{
 198	bool ret = false;
 199
 200	if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
 201		ret = !!atomic_dec_and_test(&genpd->sd_count);
 202
 203	return ret;
 204}
 205
 206static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 207{
 208	atomic_inc(&genpd->sd_count);
 209	smp_mb__after_atomic();
 210}
 211
 212#ifdef CONFIG_DEBUG_FS
 213static void genpd_update_accounting(struct generic_pm_domain *genpd)
 214{
 215	ktime_t delta, now;
 216
 217	now = ktime_get();
 218	delta = ktime_sub(now, genpd->accounting_time);
 219
 220	/*
 221	 * If genpd->status is active, it means we are just
 222	 * out of off and so update the idle time and vice
 223	 * versa.
 224	 */
 225	if (genpd->status == GPD_STATE_ACTIVE) {
 226		int state_idx = genpd->state_idx;
 227
 228		genpd->states[state_idx].idle_time =
 229			ktime_add(genpd->states[state_idx].idle_time, delta);
 230	} else {
 231		genpd->on_time = ktime_add(genpd->on_time, delta);
 232	}
 233
 234	genpd->accounting_time = now;
 235}
 236#else
 237static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
 238#endif
 239
 240static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
 241					   unsigned int state)
 242{
 243	struct generic_pm_domain_data *pd_data;
 244	struct pm_domain_data *pdd;
 245	struct gpd_link *link;
 246
 247	/* New requested state is same as Max requested state */
 248	if (state == genpd->performance_state)
 249		return state;
 250
 251	/* New requested state is higher than Max requested state */
 252	if (state > genpd->performance_state)
 253		return state;
 254
 255	/* Traverse all devices within the domain */
 256	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 257		pd_data = to_gpd_data(pdd);
 258
 259		if (pd_data->performance_state > state)
 260			state = pd_data->performance_state;
 261	}
 262
 263	/*
 264	 * Traverse all sub-domains within the domain. This can be
 265	 * done without any additional locking as the link->performance_state
 266	 * field is protected by the master genpd->lock, which is already taken.
 267	 *
 268	 * Also note that link->performance_state (subdomain's performance state
 269	 * requirement to master domain) is different from
 270	 * link->slave->performance_state (current performance state requirement
 271	 * of the devices/sub-domains of the subdomain) and so can have a
 272	 * different value.
 273	 *
 274	 * Note that we also take vote from powered-off sub-domains into account
 275	 * as the same is done for devices right now.
 276	 */
 277	list_for_each_entry(link, &genpd->master_links, master_node) {
 278		if (link->performance_state > state)
 279			state = link->performance_state;
 280	}
 281
 282	return state;
 283}
 284
 285static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
 286					unsigned int state, int depth)
 287{
 288	struct generic_pm_domain *master;
 289	struct gpd_link *link;
 290	int master_state, ret;
 291
 292	if (state == genpd->performance_state)
 293		return 0;
 294
 295	/* Propagate to masters of genpd */
 296	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 297		master = link->master;
 298
 299		if (!master->set_performance_state)
 300			continue;
 301
 302		/* Find master's performance state */
 303		ret = dev_pm_opp_xlate_performance_state(genpd->opp_table,
 304							 master->opp_table,
 305							 state);
 306		if (unlikely(ret < 0))
 307			goto err;
 308
 309		master_state = ret;
 310
 311		genpd_lock_nested(master, depth + 1);
 312
 313		link->prev_performance_state = link->performance_state;
 314		link->performance_state = master_state;
 315		master_state = _genpd_reeval_performance_state(master,
 316						master_state);
 317		ret = _genpd_set_performance_state(master, master_state, depth + 1);
 318		if (ret)
 319			link->performance_state = link->prev_performance_state;
 320
 321		genpd_unlock(master);
 322
 323		if (ret)
 324			goto err;
 325	}
 326
 327	ret = genpd->set_performance_state(genpd, state);
 328	if (ret)
 329		goto err;
 330
 331	genpd->performance_state = state;
 332	return 0;
 333
 334err:
 335	/* Encountered an error, lets rollback */
 336	list_for_each_entry_continue_reverse(link, &genpd->slave_links,
 337					     slave_node) {
 338		master = link->master;
 339
 340		if (!master->set_performance_state)
 341			continue;
 342
 343		genpd_lock_nested(master, depth + 1);
 344
 345		master_state = link->prev_performance_state;
 346		link->performance_state = master_state;
 347
 348		master_state = _genpd_reeval_performance_state(master,
 349						master_state);
 350		if (_genpd_set_performance_state(master, master_state, depth + 1)) {
 351			pr_err("%s: Failed to roll back to %d performance state\n",
 352			       master->name, master_state);
 353		}
 354
 355		genpd_unlock(master);
 356	}
 357
 358	return ret;
 359}
 360
 361/**
 362 * dev_pm_genpd_set_performance_state- Set performance state of device's power
 363 * domain.
 364 *
 365 * @dev: Device for which the performance-state needs to be set.
 366 * @state: Target performance state of the device. This can be set as 0 when the
 367 *	   device doesn't have any performance state constraints left (And so
 368 *	   the device wouldn't participate anymore to find the target
 369 *	   performance state of the genpd).
 370 *
 371 * It is assumed that the users guarantee that the genpd wouldn't be detached
 372 * while this routine is getting called.
 373 *
 374 * Returns 0 on success and negative error values on failures.
 375 */
 376int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
 377{
 378	struct generic_pm_domain *genpd;
 379	struct generic_pm_domain_data *gpd_data;
 380	unsigned int prev;
 381	int ret;
 382
 383	genpd = dev_to_genpd_safe(dev);
 384	if (!genpd)
 385		return -ENODEV;
 386
 387	if (unlikely(!genpd->set_performance_state))
 388		return -EINVAL;
 389
 390	if (WARN_ON(!dev->power.subsys_data ||
 391		     !dev->power.subsys_data->domain_data))
 392		return -EINVAL;
 393
 394	genpd_lock(genpd);
 395
 396	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
 397	prev = gpd_data->performance_state;
 398	gpd_data->performance_state = state;
 399
 400	state = _genpd_reeval_performance_state(genpd, state);
 401	ret = _genpd_set_performance_state(genpd, state, 0);
 402	if (ret)
 403		gpd_data->performance_state = prev;
 404
 405	genpd_unlock(genpd);
 406
 407	return ret;
 408}
 409EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
 410
 411static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 412{
 413	unsigned int state_idx = genpd->state_idx;
 414	ktime_t time_start;
 415	s64 elapsed_ns;
 416	int ret;
 417
 418	if (!genpd->power_on)
 419		return 0;
 420
 421	if (!timed)
 422		return genpd->power_on(genpd);
 423
 424	time_start = ktime_get();
 425	ret = genpd->power_on(genpd);
 426	if (ret)
 427		return ret;
 428
 429	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 430	if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
 431		return ret;
 432
 433	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
 434	genpd->max_off_time_changed = true;
 435	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 436		 genpd->name, "on", elapsed_ns);
 437
 438	return ret;
 439}
 440
 441static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 442{
 443	unsigned int state_idx = genpd->state_idx;
 444	ktime_t time_start;
 445	s64 elapsed_ns;
 446	int ret;
 447
 448	if (!genpd->power_off)
 449		return 0;
 450
 451	if (!timed)
 452		return genpd->power_off(genpd);
 453
 454	time_start = ktime_get();
 455	ret = genpd->power_off(genpd);
 456	if (ret)
 457		return ret;
 458
 459	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 460	if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
 461		return 0;
 462
 463	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
 464	genpd->max_off_time_changed = true;
 465	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 466		 genpd->name, "off", elapsed_ns);
 467
 468	return 0;
 469}
 470
 471/**
 472 * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
 473 * @genpd: PM domain to power off.
 474 *
 475 * Queue up the execution of genpd_power_off() unless it's already been done
 476 * before.
 477 */
 478static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 479{
 480	queue_work(pm_wq, &genpd->power_off_work);
 481}
 482
 483/**
 484 * genpd_power_off - Remove power from a given PM domain.
 485 * @genpd: PM domain to power down.
 486 * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
 487 * RPM status of the releated device is in an intermediate state, not yet turned
 488 * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
 489 * be RPM_SUSPENDED, while it tries to power off the PM domain.
 490 *
 491 * If all of the @genpd's devices have been suspended and all of its subdomains
 492 * have been powered down, remove power from @genpd.
 493 */
 494static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
 495			   unsigned int depth)
 496{
 497	struct pm_domain_data *pdd;
 498	struct gpd_link *link;
 499	unsigned int not_suspended = 0;
 500
 501	/*
 502	 * Do not try to power off the domain in the following situations:
 503	 * (1) The domain is already in the "power off" state.
 504	 * (2) System suspend is in progress.
 505	 */
 506	if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
 507		return 0;
 508
 509	/*
 510	 * Abort power off for the PM domain in the following situations:
 511	 * (1) The domain is configured as always on.
 512	 * (2) When the domain has a subdomain being powered on.
 513	 */
 514	if (genpd_is_always_on(genpd) ||
 515			genpd_is_rpm_always_on(genpd) ||
 516			atomic_read(&genpd->sd_count) > 0)
 517		return -EBUSY;
 518
 519	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 520		enum pm_qos_flags_status stat;
 521
 522		stat = dev_pm_qos_flags(pdd->dev, PM_QOS_FLAG_NO_POWER_OFF);
 523		if (stat > PM_QOS_FLAGS_NONE)
 524			return -EBUSY;
 525
 526		/*
 527		 * Do not allow PM domain to be powered off, when an IRQ safe
 528		 * device is part of a non-IRQ safe domain.
 529		 */
 530		if (!pm_runtime_suspended(pdd->dev) ||
 531			irq_safe_dev_in_no_sleep_domain(pdd->dev, genpd))
 532			not_suspended++;
 533	}
 534
 535	if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
 536		return -EBUSY;
 537
 538	if (genpd->gov && genpd->gov->power_down_ok) {
 539		if (!genpd->gov->power_down_ok(&genpd->domain))
 540			return -EAGAIN;
 541	}
 542
 543	/* Default to shallowest state. */
 544	if (!genpd->gov)
 545		genpd->state_idx = 0;
 546
 547	if (genpd->power_off) {
 548		int ret;
 549
 550		if (atomic_read(&genpd->sd_count) > 0)
 551			return -EBUSY;
 552
 553		/*
 554		 * If sd_count > 0 at this point, one of the subdomains hasn't
 555		 * managed to call genpd_power_on() for the master yet after
 556		 * incrementing it.  In that case genpd_power_on() will wait
 557		 * for us to drop the lock, so we can call .power_off() and let
 558		 * the genpd_power_on() restore power for us (this shouldn't
 559		 * happen very often).
 560		 */
 561		ret = _genpd_power_off(genpd, true);
 562		if (ret)
 563			return ret;
 564	}
 565
 566	genpd->status = GPD_STATE_POWER_OFF;
 567	genpd_update_accounting(genpd);
 568
 569	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 570		genpd_sd_counter_dec(link->master);
 571		genpd_lock_nested(link->master, depth + 1);
 572		genpd_power_off(link->master, false, depth + 1);
 573		genpd_unlock(link->master);
 574	}
 575
 576	return 0;
 577}
 578
 579/**
 580 * genpd_power_on - Restore power to a given PM domain and its masters.
 581 * @genpd: PM domain to power up.
 582 * @depth: nesting count for lockdep.
 583 *
 584 * Restore power to @genpd and all of its masters so that it is possible to
 585 * resume a device belonging to it.
 586 */
 587static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
 588{
 589	struct gpd_link *link;
 590	int ret = 0;
 591
 592	if (genpd_status_on(genpd))
 
 593		return 0;
 594
 595	/*
 596	 * The list is guaranteed not to change while the loop below is being
 597	 * executed, unless one of the masters' .power_on() callbacks fiddles
 598	 * with it.
 599	 */
 600	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 601		struct generic_pm_domain *master = link->master;
 602
 603		genpd_sd_counter_inc(master);
 604
 605		genpd_lock_nested(master, depth + 1);
 606		ret = genpd_power_on(master, depth + 1);
 607		genpd_unlock(master);
 608
 609		if (ret) {
 610			genpd_sd_counter_dec(master);
 611			goto err;
 612		}
 613	}
 614
 615	ret = _genpd_power_on(genpd, true);
 616	if (ret)
 617		goto err;
 618
 619	genpd->status = GPD_STATE_ACTIVE;
 620	genpd_update_accounting(genpd);
 621
 622	return 0;
 623
 624 err:
 625	list_for_each_entry_continue_reverse(link,
 626					&genpd->slave_links,
 627					slave_node) {
 628		genpd_sd_counter_dec(link->master);
 629		genpd_lock_nested(link->master, depth + 1);
 630		genpd_power_off(link->master, false, depth + 1);
 631		genpd_unlock(link->master);
 632	}
 633
 634	return ret;
 635}
 636
 
 
 
 
 
 
 
 
 
 
 
 637static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 638				     unsigned long val, void *ptr)
 639{
 640	struct generic_pm_domain_data *gpd_data;
 641	struct device *dev;
 642
 643	gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
 644	dev = gpd_data->base.dev;
 645
 646	for (;;) {
 647		struct generic_pm_domain *genpd;
 648		struct pm_domain_data *pdd;
 649
 650		spin_lock_irq(&dev->power.lock);
 651
 652		pdd = dev->power.subsys_data ?
 653				dev->power.subsys_data->domain_data : NULL;
 654		if (pdd) {
 655			to_gpd_data(pdd)->td.constraint_changed = true;
 656			genpd = dev_to_genpd(dev);
 657		} else {
 658			genpd = ERR_PTR(-ENODATA);
 659		}
 660
 661		spin_unlock_irq(&dev->power.lock);
 662
 663		if (!IS_ERR(genpd)) {
 664			genpd_lock(genpd);
 665			genpd->max_off_time_changed = true;
 666			genpd_unlock(genpd);
 667		}
 668
 669		dev = dev->parent;
 670		if (!dev || dev->power.ignore_children)
 671			break;
 672	}
 673
 674	return NOTIFY_DONE;
 675}
 676
 677/**
 678 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 679 * @work: Work structure used for scheduling the execution of this function.
 
 
 
 
 680 */
 681static void genpd_power_off_work_fn(struct work_struct *work)
 682{
 683	struct generic_pm_domain *genpd;
 
 
 684
 685	genpd = container_of(work, struct generic_pm_domain, power_off_work);
 
 
 
 
 
 
 
 686
 687	genpd_lock(genpd);
 688	genpd_power_off(genpd, false, 0);
 689	genpd_unlock(genpd);
 690}
 691
 692/**
 693 * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
 694 * @dev: Device to handle.
 695 */
 696static int __genpd_runtime_suspend(struct device *dev)
 697{
 698	int (*cb)(struct device *__dev);
 699
 700	if (dev->type && dev->type->pm)
 701		cb = dev->type->pm->runtime_suspend;
 702	else if (dev->class && dev->class->pm)
 703		cb = dev->class->pm->runtime_suspend;
 704	else if (dev->bus && dev->bus->pm)
 705		cb = dev->bus->pm->runtime_suspend;
 706	else
 707		cb = NULL;
 708
 709	if (!cb && dev->driver && dev->driver->pm)
 710		cb = dev->driver->pm->runtime_suspend;
 
 711
 712	return cb ? cb(dev) : 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 713}
 714
 715/**
 716 * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
 717 * @dev: Device to handle.
 718 */
 719static int __genpd_runtime_resume(struct device *dev)
 720{
 721	int (*cb)(struct device *__dev);
 722
 723	if (dev->type && dev->type->pm)
 724		cb = dev->type->pm->runtime_resume;
 725	else if (dev->class && dev->class->pm)
 726		cb = dev->class->pm->runtime_resume;
 727	else if (dev->bus && dev->bus->pm)
 728		cb = dev->bus->pm->runtime_resume;
 729	else
 730		cb = NULL;
 731
 732	if (!cb && dev->driver && dev->driver->pm)
 733		cb = dev->driver->pm->runtime_resume;
 734
 735	return cb ? cb(dev) : 0;
 
 
 736}
 737
 738/**
 739 * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 740 * @dev: Device to suspend.
 741 *
 742 * Carry out a runtime suspend of a device under the assumption that its
 743 * pm_domain field points to the domain member of an object of type
 744 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 745 */
 746static int genpd_runtime_suspend(struct device *dev)
 747{
 748	struct generic_pm_domain *genpd;
 749	bool (*suspend_ok)(struct device *__dev);
 750	struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
 751	bool runtime_pm = pm_runtime_enabled(dev);
 752	ktime_t time_start;
 753	s64 elapsed_ns;
 754	int ret;
 755
 756	dev_dbg(dev, "%s()\n", __func__);
 757
 758	genpd = dev_to_genpd(dev);
 759	if (IS_ERR(genpd))
 760		return -EINVAL;
 761
 762	/*
 763	 * A runtime PM centric subsystem/driver may re-use the runtime PM
 764	 * callbacks for other purposes than runtime PM. In those scenarios
 765	 * runtime PM is disabled. Under these circumstances, we shall skip
 766	 * validating/measuring the PM QoS latency.
 767	 */
 768	suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
 769	if (runtime_pm && suspend_ok && !suspend_ok(dev))
 770		return -EBUSY;
 771
 772	/* Measure suspend latency. */
 773	time_start = 0;
 774	if (runtime_pm)
 775		time_start = ktime_get();
 776
 777	ret = __genpd_runtime_suspend(dev);
 778	if (ret)
 779		return ret;
 780
 781	ret = genpd_stop_dev(genpd, dev);
 782	if (ret) {
 783		__genpd_runtime_resume(dev);
 784		return ret;
 785	}
 786
 787	/* Update suspend latency value if the measured time exceeds it. */
 788	if (runtime_pm) {
 789		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 790		if (elapsed_ns > td->suspend_latency_ns) {
 791			td->suspend_latency_ns = elapsed_ns;
 792			dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
 793				elapsed_ns);
 794			genpd->max_off_time_changed = true;
 795			td->constraint_changed = true;
 796		}
 797	}
 798
 799	/*
 800	 * If power.irq_safe is set, this routine may be run with
 801	 * IRQs disabled, so suspend only if the PM domain also is irq_safe.
 802	 */
 803	if (irq_safe_dev_in_no_sleep_domain(dev, genpd))
 804		return 0;
 805
 806	genpd_lock(genpd);
 807	genpd_power_off(genpd, true, 0);
 808	genpd_unlock(genpd);
 809
 810	return 0;
 811}
 812
 813/**
 814 * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
 815 * @dev: Device to resume.
 816 *
 817 * Carry out a runtime resume of a device under the assumption that its
 818 * pm_domain field points to the domain member of an object of type
 819 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 820 */
 821static int genpd_runtime_resume(struct device *dev)
 822{
 823	struct generic_pm_domain *genpd;
 824	struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
 825	bool runtime_pm = pm_runtime_enabled(dev);
 826	ktime_t time_start;
 827	s64 elapsed_ns;
 828	int ret;
 829	bool timed = true;
 830
 831	dev_dbg(dev, "%s()\n", __func__);
 832
 833	genpd = dev_to_genpd(dev);
 834	if (IS_ERR(genpd))
 835		return -EINVAL;
 836
 837	/*
 838	 * As we don't power off a non IRQ safe domain, which holds
 839	 * an IRQ safe device, we don't need to restore power to it.
 840	 */
 841	if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) {
 842		timed = false;
 843		goto out;
 844	}
 845
 846	genpd_lock(genpd);
 847	ret = genpd_power_on(genpd, 0);
 848	genpd_unlock(genpd);
 849
 850	if (ret)
 851		return ret;
 852
 853 out:
 854	/* Measure resume latency. */
 855	time_start = 0;
 856	if (timed && runtime_pm)
 857		time_start = ktime_get();
 858
 859	ret = genpd_start_dev(genpd, dev);
 860	if (ret)
 861		goto err_poweroff;
 862
 863	ret = __genpd_runtime_resume(dev);
 864	if (ret)
 865		goto err_stop;
 866
 867	/* Update resume latency value if the measured time exceeds it. */
 868	if (timed && runtime_pm) {
 869		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 870		if (elapsed_ns > td->resume_latency_ns) {
 871			td->resume_latency_ns = elapsed_ns;
 872			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
 873				elapsed_ns);
 874			genpd->max_off_time_changed = true;
 875			td->constraint_changed = true;
 876		}
 877	}
 878
 879	return 0;
 880
 881err_stop:
 882	genpd_stop_dev(genpd, dev);
 883err_poweroff:
 884	if (!pm_runtime_is_irq_safe(dev) ||
 885		(pm_runtime_is_irq_safe(dev) && genpd_is_irq_safe(genpd))) {
 886		genpd_lock(genpd);
 887		genpd_power_off(genpd, true, 0);
 888		genpd_unlock(genpd);
 889	}
 890
 891	return ret;
 892}
 893
 894static bool pd_ignore_unused;
 895static int __init pd_ignore_unused_setup(char *__unused)
 896{
 897	pd_ignore_unused = true;
 898	return 1;
 899}
 900__setup("pd_ignore_unused", pd_ignore_unused_setup);
 901
 902/**
 903 * genpd_power_off_unused - Power off all PM domains with no devices in use.
 904 */
 905static int __init genpd_power_off_unused(void)
 906{
 907	struct generic_pm_domain *genpd;
 908
 909	if (pd_ignore_unused) {
 910		pr_warn("genpd: Not disabling unused power domains\n");
 911		return 0;
 912	}
 913
 914	mutex_lock(&gpd_list_lock);
 915
 916	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
 917		genpd_queue_power_off_work(genpd);
 918
 919	mutex_unlock(&gpd_list_lock);
 920
 921	return 0;
 922}
 923late_initcall(genpd_power_off_unused);
 924
 925#if defined(CONFIG_PM_SLEEP) || defined(CONFIG_PM_GENERIC_DOMAINS_OF)
 926
 927static bool genpd_present(const struct generic_pm_domain *genpd)
 
 
 
 
 928{
 929	const struct generic_pm_domain *gpd;
 930
 931	if (IS_ERR_OR_NULL(genpd))
 932		return false;
 933
 934	list_for_each_entry(gpd, &gpd_list, gpd_list_node)
 935		if (gpd == genpd)
 936			return true;
 937
 938	return false;
 939}
 940
 941#endif
 942
 943#ifdef CONFIG_PM_SLEEP
 
 
 944
 945/**
 946 * genpd_sync_power_off - Synchronously power off a PM domain and its masters.
 947 * @genpd: PM domain to power off, if possible.
 948 * @use_lock: use the lock.
 949 * @depth: nesting count for lockdep.
 950 *
 951 * Check if the given PM domain can be powered off (during system suspend or
 952 * hibernation) and do that if so.  Also, in that case propagate to its masters.
 953 *
 954 * This function is only called in "noirq" and "syscore" stages of system power
 955 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
 956 * these cases the lock must be held.
 
 957 */
 958static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
 959				 unsigned int depth)
 960{
 961	struct gpd_link *link;
 962
 963	if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
 964		return;
 965
 966	if (genpd->suspended_count != genpd->device_count
 967	    || atomic_read(&genpd->sd_count) > 0)
 968		return;
 969
 970	/* Choose the deepest state when suspending */
 971	genpd->state_idx = genpd->state_count - 1;
 972	if (_genpd_power_off(genpd, false))
 973		return;
 974
 975	genpd->status = GPD_STATE_POWER_OFF;
 976
 977	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 978		genpd_sd_counter_dec(link->master);
 979
 980		if (use_lock)
 981			genpd_lock_nested(link->master, depth + 1);
 982
 983		genpd_sync_power_off(link->master, use_lock, depth + 1);
 984
 985		if (use_lock)
 986			genpd_unlock(link->master);
 987	}
 988}
 989
 990/**
 991 * genpd_sync_power_on - Synchronously power on a PM domain and its masters.
 992 * @genpd: PM domain to power on.
 993 * @use_lock: use the lock.
 994 * @depth: nesting count for lockdep.
 995 *
 996 * This function is only called in "noirq" and "syscore" stages of system power
 997 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
 998 * these cases the lock must be held.
 
 999 */
1000static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
1001				unsigned int depth)
1002{
1003	struct gpd_link *link;
1004
1005	if (genpd_status_on(genpd))
1006		return;
1007
1008	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 
1009		genpd_sd_counter_inc(link->master);
1010
1011		if (use_lock)
1012			genpd_lock_nested(link->master, depth + 1);
1013
1014		genpd_sync_power_on(link->master, use_lock, depth + 1);
1015
1016		if (use_lock)
1017			genpd_unlock(link->master);
1018	}
1019
1020	_genpd_power_on(genpd, false);
1021
1022	genpd->status = GPD_STATE_ACTIVE;
1023}
1024
1025/**
1026 * resume_needed - Check whether to resume a device before system suspend.
1027 * @dev: Device to check.
1028 * @genpd: PM domain the device belongs to.
1029 *
1030 * There are two cases in which a device that can wake up the system from sleep
1031 * states should be resumed by genpd_prepare(): (1) if the device is enabled
1032 * to wake up the system and it has to remain active for this purpose while the
1033 * system is in the sleep state and (2) if the device is not enabled to wake up
1034 * the system from sleep states and it generally doesn't generate wakeup signals
1035 * by itself (those signals are generated on its behalf by other parts of the
1036 * system).  In the latter case it may be necessary to reconfigure the device's
1037 * wakeup settings during system suspend, because it may have been set up to
1038 * signal remote wakeup from the system's working state as needed by runtime PM.
1039 * Return 'true' in either of the above cases.
1040 */
1041static bool resume_needed(struct device *dev,
1042			  const struct generic_pm_domain *genpd)
1043{
1044	bool active_wakeup;
1045
1046	if (!device_can_wakeup(dev))
1047		return false;
1048
1049	active_wakeup = genpd_is_active_wakeup(genpd);
1050	return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
1051}
1052
1053/**
1054 * genpd_prepare - Start power transition of a device in a PM domain.
1055 * @dev: Device to start the transition of.
1056 *
1057 * Start a power transition of a device (during a system-wide power transition)
1058 * under the assumption that its pm_domain field points to the domain member of
1059 * an object of type struct generic_pm_domain representing a PM domain
1060 * consisting of I/O devices.
1061 */
1062static int genpd_prepare(struct device *dev)
1063{
1064	struct generic_pm_domain *genpd;
1065	int ret;
1066
1067	dev_dbg(dev, "%s()\n", __func__);
1068
1069	genpd = dev_to_genpd(dev);
1070	if (IS_ERR(genpd))
1071		return -EINVAL;
1072
1073	/*
1074	 * If a wakeup request is pending for the device, it should be woken up
1075	 * at this point and a system wakeup event should be reported if it's
1076	 * set up to wake up the system from sleep states.
1077	 */
 
 
 
 
 
 
 
 
 
1078	if (resume_needed(dev, genpd))
1079		pm_runtime_resume(dev);
1080
1081	genpd_lock(genpd);
1082
1083	if (genpd->prepared_count++ == 0)
1084		genpd->suspended_count = 0;
 
 
1085
1086	genpd_unlock(genpd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1087
1088	ret = pm_generic_prepare(dev);
1089	if (ret < 0) {
1090		genpd_lock(genpd);
1091
1092		genpd->prepared_count--;
 
1093
1094		genpd_unlock(genpd);
 
1095	}
1096
1097	/* Never return 1, as genpd don't cope with the direct_complete path. */
1098	return ret >= 0 ? 0 : ret;
1099}
1100
1101/**
1102 * genpd_finish_suspend - Completion of suspend or hibernation of device in an
1103 *   I/O pm domain.
1104 * @dev: Device to suspend.
1105 * @poweroff: Specifies if this is a poweroff_noirq or suspend_noirq callback.
1106 *
1107 * Stop the device and remove power from the domain if all devices in it have
1108 * been stopped.
 
1109 */
1110static int genpd_finish_suspend(struct device *dev, bool poweroff)
1111{
1112	struct generic_pm_domain *genpd;
1113	int ret = 0;
 
1114
1115	genpd = dev_to_genpd(dev);
1116	if (IS_ERR(genpd))
1117		return -EINVAL;
1118
1119	if (poweroff)
1120		ret = pm_generic_poweroff_noirq(dev);
1121	else
1122		ret = pm_generic_suspend_noirq(dev);
1123	if (ret)
1124		return ret;
1125
1126	if (dev->power.wakeup_path && genpd_is_active_wakeup(genpd))
1127		return 0;
 
 
 
 
 
 
 
 
 
1128
1129	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1130	    !pm_runtime_status_suspended(dev)) {
1131		ret = genpd_stop_dev(genpd, dev);
1132		if (ret) {
1133			if (poweroff)
1134				pm_generic_restore_noirq(dev);
1135			else
1136				pm_generic_resume_noirq(dev);
1137			return ret;
1138		}
1139	}
1140
1141	genpd_lock(genpd);
1142	genpd->suspended_count++;
1143	genpd_sync_power_off(genpd, true, 0);
1144	genpd_unlock(genpd);
1145
1146	return 0;
1147}
1148
1149/**
1150 * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1151 * @dev: Device to suspend.
1152 *
1153 * Stop the device and remove power from the domain if all devices in it have
1154 * been stopped.
1155 */
1156static int genpd_suspend_noirq(struct device *dev)
1157{
 
 
1158	dev_dbg(dev, "%s()\n", __func__);
1159
1160	return genpd_finish_suspend(dev, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1161}
1162
1163/**
1164 * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1165 * @dev: Device to resume.
1166 *
1167 * Restore power to the device's PM domain, if necessary, and start the device.
1168 */
1169static int genpd_resume_noirq(struct device *dev)
1170{
1171	struct generic_pm_domain *genpd;
1172	int ret;
1173
1174	dev_dbg(dev, "%s()\n", __func__);
1175
1176	genpd = dev_to_genpd(dev);
1177	if (IS_ERR(genpd))
1178		return -EINVAL;
1179
1180	if (dev->power.wakeup_path && genpd_is_active_wakeup(genpd))
1181		return pm_generic_resume_noirq(dev);
 
1182
1183	genpd_lock(genpd);
1184	genpd_sync_power_on(genpd, true, 0);
 
 
 
 
1185	genpd->suspended_count--;
1186	genpd_unlock(genpd);
1187
1188	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1189	    !pm_runtime_status_suspended(dev)) {
1190		ret = genpd_start_dev(genpd, dev);
1191		if (ret)
1192			return ret;
1193	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1194
1195	return pm_generic_resume_noirq(dev);
 
 
 
 
1196}
1197
1198/**
1199 * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1200 * @dev: Device to freeze.
1201 *
1202 * Carry out a late freeze of a device under the assumption that its
1203 * pm_domain field points to the domain member of an object of type
1204 * struct generic_pm_domain representing a power domain consisting of I/O
1205 * devices.
1206 */
1207static int genpd_freeze_noirq(struct device *dev)
1208{
1209	const struct generic_pm_domain *genpd;
1210	int ret = 0;
1211
1212	dev_dbg(dev, "%s()\n", __func__);
1213
1214	genpd = dev_to_genpd(dev);
1215	if (IS_ERR(genpd))
1216		return -EINVAL;
1217
1218	ret = pm_generic_freeze_noirq(dev);
1219	if (ret)
1220		return ret;
1221
1222	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1223	    !pm_runtime_status_suspended(dev))
1224		ret = genpd_stop_dev(genpd, dev);
 
 
 
 
 
 
 
 
 
1225
1226	return ret;
 
 
 
 
 
 
1227}
1228
1229/**
1230 * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1231 * @dev: Device to thaw.
1232 *
1233 * Start the device, unless power has been removed from the domain already
1234 * before the system transition.
1235 */
1236static int genpd_thaw_noirq(struct device *dev)
1237{
1238	const struct generic_pm_domain *genpd;
1239	int ret = 0;
1240
1241	dev_dbg(dev, "%s()\n", __func__);
1242
1243	genpd = dev_to_genpd(dev);
1244	if (IS_ERR(genpd))
1245		return -EINVAL;
1246
1247	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1248	    !pm_runtime_status_suspended(dev)) {
1249		ret = genpd_start_dev(genpd, dev);
1250		if (ret)
1251			return ret;
1252	}
 
 
 
 
 
 
 
 
 
 
1253
1254	return pm_generic_thaw_noirq(dev);
 
 
 
 
 
 
1255}
1256
1257/**
1258 * genpd_poweroff_noirq - Completion of hibernation of device in an
1259 *   I/O PM domain.
1260 * @dev: Device to poweroff.
1261 *
1262 * Stop the device and remove power from the domain if all devices in it have
1263 * been stopped.
 
1264 */
1265static int genpd_poweroff_noirq(struct device *dev)
1266{
 
 
1267	dev_dbg(dev, "%s()\n", __func__);
1268
1269	return genpd_finish_suspend(dev, true);
 
 
 
 
1270}
1271
1272/**
1273 * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1274 * @dev: Device to resume.
1275 *
1276 * Make sure the domain will be in the same power state as before the
1277 * hibernation the system is resuming from and start the device if necessary.
1278 */
1279static int genpd_restore_noirq(struct device *dev)
1280{
1281	struct generic_pm_domain *genpd;
1282	int ret = 0;
1283
1284	dev_dbg(dev, "%s()\n", __func__);
1285
1286	genpd = dev_to_genpd(dev);
1287	if (IS_ERR(genpd))
1288		return -EINVAL;
1289
1290	/*
 
 
 
 
1291	 * At this point suspended_count == 0 means we are being run for the
1292	 * first time for the given domain in the present cycle.
1293	 */
1294	genpd_lock(genpd);
1295	if (genpd->suspended_count++ == 0)
1296		/*
1297		 * The boot kernel might put the domain into arbitrary state,
1298		 * so make it appear as powered off to genpd_sync_power_on(),
1299		 * so that it tries to power it on in case it was really off.
1300		 */
1301		genpd->status = GPD_STATE_POWER_OFF;
 
 
 
 
 
 
1302
1303	genpd_sync_power_on(genpd, true, 0);
1304	genpd_unlock(genpd);
1305
1306	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1307	    !pm_runtime_status_suspended(dev)) {
1308		ret = genpd_start_dev(genpd, dev);
1309		if (ret)
1310			return ret;
1311	}
1312
1313	return pm_generic_restore_noirq(dev);
 
 
 
 
 
1314}
1315
1316/**
1317 * genpd_complete - Complete power transition of a device in a power domain.
1318 * @dev: Device to complete the transition of.
1319 *
1320 * Complete a power transition of a device (during a system-wide power
1321 * transition) under the assumption that its pm_domain field points to the
1322 * domain member of an object of type struct generic_pm_domain representing
1323 * a power domain consisting of I/O devices.
1324 */
1325static void genpd_complete(struct device *dev)
1326{
1327	struct generic_pm_domain *genpd;
 
1328
1329	dev_dbg(dev, "%s()\n", __func__);
1330
1331	genpd = dev_to_genpd(dev);
1332	if (IS_ERR(genpd))
1333		return;
1334
1335	pm_generic_complete(dev);
1336
1337	genpd_lock(genpd);
1338
1339	genpd->prepared_count--;
1340	if (!genpd->prepared_count)
1341		genpd_queue_power_off_work(genpd);
1342
1343	genpd_unlock(genpd);
 
 
 
 
 
 
 
1344}
1345
1346/**
1347 * 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 */
1353static void genpd_syscore_switch(struct device *dev, bool suspend)
1354{
1355	struct generic_pm_domain *genpd;
1356
1357	genpd = dev_to_genpd(dev);
1358	if (!genpd_present(genpd))
1359		return;
1360
1361	if (suspend) {
1362		genpd->suspended_count++;
1363		genpd_sync_power_off(genpd, false, 0);
1364	} else {
1365		genpd_sync_power_on(genpd, false, 0);
1366		genpd->suspended_count--;
1367	}
1368}
1369
1370void pm_genpd_syscore_poweroff(struct device *dev)
1371{
1372	genpd_syscore_switch(dev, true);
1373}
1374EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
1375
1376void pm_genpd_syscore_poweron(struct device *dev)
1377{
1378	genpd_syscore_switch(dev, false);
1379}
1380EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1381
1382#else /* !CONFIG_PM_SLEEP */
1383
1384#define genpd_prepare		NULL
1385#define genpd_suspend_noirq	NULL
1386#define genpd_resume_noirq	NULL
1387#define genpd_freeze_noirq	NULL
1388#define genpd_thaw_noirq	NULL
1389#define genpd_poweroff_noirq	NULL
1390#define genpd_restore_noirq	NULL
1391#define genpd_complete		NULL
 
 
 
 
 
 
 
1392
1393#endif /* CONFIG_PM_SLEEP */
1394
1395static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev)
 
 
1396{
1397	struct generic_pm_domain_data *gpd_data;
1398	int ret;
1399
1400	ret = dev_pm_get_subsys_data(dev);
1401	if (ret)
1402		return ERR_PTR(ret);
1403
1404	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1405	if (!gpd_data) {
1406		ret = -ENOMEM;
1407		goto err_put;
1408	}
1409
 
 
 
1410	gpd_data->base.dev = dev;
1411	gpd_data->td.constraint_changed = true;
1412	gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
1413	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1414
1415	spin_lock_irq(&dev->power.lock);
1416
1417	if (dev->power.subsys_data->domain_data) {
1418		ret = -EINVAL;
1419		goto err_free;
1420	}
1421
1422	dev->power.subsys_data->domain_data = &gpd_data->base;
1423
1424	spin_unlock_irq(&dev->power.lock);
1425
 
 
1426	return gpd_data;
1427
1428 err_free:
1429	spin_unlock_irq(&dev->power.lock);
1430	kfree(gpd_data);
1431 err_put:
1432	dev_pm_put_subsys_data(dev);
1433	return ERR_PTR(ret);
1434}
1435
1436static void genpd_free_dev_data(struct device *dev,
1437				struct generic_pm_domain_data *gpd_data)
1438{
 
 
1439	spin_lock_irq(&dev->power.lock);
1440
1441	dev->power.subsys_data->domain_data = NULL;
1442
1443	spin_unlock_irq(&dev->power.lock);
1444
1445	kfree(gpd_data);
1446	dev_pm_put_subsys_data(dev);
1447}
1448
1449static void genpd_update_cpumask(struct generic_pm_domain *genpd,
1450				 int cpu, bool set, unsigned int depth)
1451{
1452	struct gpd_link *link;
1453
1454	if (!genpd_is_cpu_domain(genpd))
1455		return;
1456
1457	list_for_each_entry(link, &genpd->slave_links, slave_node) {
1458		struct generic_pm_domain *master = link->master;
1459
1460		genpd_lock_nested(master, depth + 1);
1461		genpd_update_cpumask(master, cpu, set, depth + 1);
1462		genpd_unlock(master);
1463	}
1464
1465	if (set)
1466		cpumask_set_cpu(cpu, genpd->cpus);
1467	else
1468		cpumask_clear_cpu(cpu, genpd->cpus);
1469}
1470
1471static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
1472{
1473	if (cpu >= 0)
1474		genpd_update_cpumask(genpd, cpu, true, 0);
1475}
1476
1477static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
1478{
1479	if (cpu >= 0)
1480		genpd_update_cpumask(genpd, cpu, false, 0);
1481}
1482
1483static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
1484{
1485	int cpu;
1486
1487	if (!genpd_is_cpu_domain(genpd))
1488		return -1;
1489
1490	for_each_possible_cpu(cpu) {
1491		if (get_cpu_device(cpu) == dev)
1492			return cpu;
1493	}
1494
1495	return -1;
1496}
1497
1498static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1499			    struct device *base_dev)
1500{
1501	struct generic_pm_domain_data *gpd_data;
1502	int ret;
1503
1504	dev_dbg(dev, "%s()\n", __func__);
1505
1506	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1507		return -EINVAL;
1508
1509	gpd_data = genpd_alloc_dev_data(dev);
1510	if (IS_ERR(gpd_data))
1511		return PTR_ERR(gpd_data);
1512
1513	gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
 
 
 
 
 
1514
1515	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1516	if (ret)
1517		goto out;
1518
1519	genpd_lock(genpd);
1520
1521	genpd_set_cpumask(genpd, gpd_data->cpu);
1522	dev_pm_domain_set(dev, &genpd->domain);
1523
1524	genpd->device_count++;
1525	genpd->max_off_time_changed = true;
1526
1527	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1528
1529	genpd_unlock(genpd);
1530 out:
 
 
1531	if (ret)
1532		genpd_free_dev_data(dev, gpd_data);
1533	else
1534		dev_pm_qos_add_notifier(dev, &gpd_data->nb,
1535					DEV_PM_QOS_RESUME_LATENCY);
1536
1537	return ret;
1538}
 
1539
1540/**
1541 * pm_genpd_add_device - Add a device to an I/O PM domain.
1542 * @genpd: PM domain to add the device to.
1543 * @dev: Device to be added.
1544 */
1545int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
1546{
1547	int ret;
1548
1549	mutex_lock(&gpd_list_lock);
1550	ret = genpd_add_device(genpd, dev, dev);
1551	mutex_unlock(&gpd_list_lock);
1552
1553	return ret;
1554}
1555EXPORT_SYMBOL_GPL(pm_genpd_add_device);
1556
1557static int genpd_remove_device(struct generic_pm_domain *genpd,
1558			       struct device *dev)
1559{
1560	struct generic_pm_domain_data *gpd_data;
1561	struct pm_domain_data *pdd;
1562	int ret = 0;
1563
1564	dev_dbg(dev, "%s()\n", __func__);
1565
 
 
 
 
1566	pdd = dev->power.subsys_data->domain_data;
1567	gpd_data = to_gpd_data(pdd);
1568	dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
1569				   DEV_PM_QOS_RESUME_LATENCY);
1570
1571	genpd_lock(genpd);
1572
1573	if (genpd->prepared_count > 0) {
1574		ret = -EAGAIN;
1575		goto out;
1576	}
1577
1578	genpd->device_count--;
1579	genpd->max_off_time_changed = true;
1580
1581	genpd_clear_cpumask(genpd, gpd_data->cpu);
1582	dev_pm_domain_set(dev, NULL);
1583
1584	list_del_init(&pdd->list_node);
1585
1586	genpd_unlock(genpd);
1587
1588	if (genpd->detach_dev)
1589		genpd->detach_dev(genpd, dev);
1590
1591	genpd_free_dev_data(dev, gpd_data);
1592
1593	return 0;
1594
1595 out:
1596	genpd_unlock(genpd);
1597	dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
1598
1599	return ret;
1600}
 
1601
1602/**
1603 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1604 * @dev: Device to be removed.
 
1605 */
1606int pm_genpd_remove_device(struct device *dev)
1607{
1608	struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
1609
1610	if (!genpd)
1611		return -EINVAL;
1612
1613	return genpd_remove_device(genpd, dev);
1614}
1615EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1616
1617static int genpd_add_subdomain(struct generic_pm_domain *genpd,
1618			       struct generic_pm_domain *subdomain)
1619{
1620	struct gpd_link *link, *itr;
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	/*
1628	 * If the domain can be powered on/off in an IRQ safe
1629	 * context, ensure that the subdomain can also be
1630	 * powered on/off in that context.
1631	 */
1632	if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
1633		WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
1634				genpd->name, subdomain->name);
1635		return -EINVAL;
1636	}
1637
1638	link = kzalloc(sizeof(*link), GFP_KERNEL);
1639	if (!link)
1640		return -ENOMEM;
1641
1642	genpd_lock(subdomain);
1643	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1644
1645	if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
 
1646		ret = -EINVAL;
1647		goto out;
1648	}
1649
1650	list_for_each_entry(itr, &genpd->master_links, master_node) {
1651		if (itr->slave == subdomain && itr->master == genpd) {
1652			ret = -EINVAL;
1653			goto out;
1654		}
1655	}
1656
1657	link->master = genpd;
1658	list_add_tail(&link->master_node, &genpd->master_links);
1659	link->slave = subdomain;
1660	list_add_tail(&link->slave_node, &subdomain->slave_links);
1661	if (genpd_status_on(subdomain))
1662		genpd_sd_counter_inc(genpd);
1663
1664 out:
1665	genpd_unlock(genpd);
1666	genpd_unlock(subdomain);
1667	if (ret)
1668		kfree(link);
1669	return ret;
1670}
1671
1672/**
1673 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1674 * @genpd: Master PM domain to add the subdomain to.
1675 * @subdomain: Subdomain to be added.
1676 */
1677int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1678			   struct generic_pm_domain *subdomain)
1679{
1680	int ret;
1681
1682	mutex_lock(&gpd_list_lock);
1683	ret = genpd_add_subdomain(genpd, subdomain);
1684	mutex_unlock(&gpd_list_lock);
1685
1686	return ret;
1687}
1688EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1689
1690/**
1691 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1692 * @genpd: Master PM domain to remove the subdomain from.
1693 * @subdomain: Subdomain to be removed.
1694 */
1695int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1696			      struct generic_pm_domain *subdomain)
1697{
1698	struct gpd_link *l, *link;
1699	int ret = -EINVAL;
1700
1701	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1702		return -EINVAL;
1703
1704	genpd_lock(subdomain);
1705	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1706
1707	if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
1708		pr_warn("%s: unable to remove subdomain %s\n",
1709			genpd->name, subdomain->name);
1710		ret = -EBUSY;
1711		goto out;
1712	}
1713
1714	list_for_each_entry_safe(link, l, &genpd->master_links, master_node) {
1715		if (link->slave != subdomain)
1716			continue;
1717
1718		list_del(&link->master_node);
1719		list_del(&link->slave_node);
1720		kfree(link);
1721		if (genpd_status_on(subdomain))
1722			genpd_sd_counter_dec(genpd);
1723
1724		ret = 0;
1725		break;
1726	}
1727
1728out:
1729	genpd_unlock(genpd);
1730	genpd_unlock(subdomain);
1731
1732	return ret;
1733}
1734EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1735
1736static void genpd_free_default_power_state(struct genpd_power_state *states,
1737					   unsigned int state_count)
1738{
1739	kfree(states);
1740}
1741
1742static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
 
 
 
 
1743{
1744	struct genpd_power_state *state;
1745
1746	state = kzalloc(sizeof(*state), GFP_KERNEL);
1747	if (!state)
1748		return -ENOMEM;
 
 
 
 
 
1749
1750	genpd->states = state;
1751	genpd->state_count = 1;
1752	genpd->free_states = genpd_free_default_power_state;
1753
1754	return 0;
1755}
1756
1757static void genpd_lock_init(struct generic_pm_domain *genpd)
 
 
 
 
1758{
1759	if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
1760		spin_lock_init(&genpd->slock);
1761		genpd->lock_ops = &genpd_spin_ops;
1762	} else {
1763		mutex_init(&genpd->mlock);
1764		genpd->lock_ops = &genpd_mtx_ops;
1765	}
 
 
 
 
 
 
 
 
1766}
1767
1768/**
1769 * pm_genpd_init - Initialize a generic I/O PM domain object.
1770 * @genpd: PM domain object to initialize.
1771 * @gov: PM domain governor to associate with the domain (may be NULL).
1772 * @is_off: Initial value of the domain's power_is_off field.
1773 *
1774 * Returns 0 on successful initialization, else a negative error code.
1775 */
1776int pm_genpd_init(struct generic_pm_domain *genpd,
1777		  struct dev_power_governor *gov, bool is_off)
1778{
1779	int ret;
1780
1781	if (IS_ERR_OR_NULL(genpd))
1782		return -EINVAL;
1783
1784	INIT_LIST_HEAD(&genpd->master_links);
1785	INIT_LIST_HEAD(&genpd->slave_links);
1786	INIT_LIST_HEAD(&genpd->dev_list);
1787	genpd_lock_init(genpd);
1788	genpd->gov = gov;
1789	INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
1790	atomic_set(&genpd->sd_count, 0);
1791	genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
1792	genpd->device_count = 0;
1793	genpd->max_off_time_ns = -1;
1794	genpd->max_off_time_changed = true;
1795	genpd->provider = NULL;
1796	genpd->has_provider = false;
1797	genpd->accounting_time = ktime_get();
1798	genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
1799	genpd->domain.ops.runtime_resume = genpd_runtime_resume;
1800	genpd->domain.ops.prepare = genpd_prepare;
1801	genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
1802	genpd->domain.ops.resume_noirq = genpd_resume_noirq;
1803	genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
1804	genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
1805	genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
1806	genpd->domain.ops.restore_noirq = genpd_restore_noirq;
1807	genpd->domain.ops.complete = genpd_complete;
 
 
 
 
 
 
 
 
 
 
 
1808
1809	if (genpd->flags & GENPD_FLAG_PM_CLK) {
1810		genpd->dev_ops.stop = pm_clk_suspend;
1811		genpd->dev_ops.start = pm_clk_resume;
1812	}
1813
1814	/* Always-on domains must be powered on at initialization. */
1815	if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
1816			!genpd_status_on(genpd))
1817		return -EINVAL;
1818
1819	if (genpd_is_cpu_domain(genpd) &&
1820	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
1821		return -ENOMEM;
1822
1823	/* Use only one "off" state if there were no states declared */
1824	if (genpd->state_count == 0) {
1825		ret = genpd_set_default_power_state(genpd);
1826		if (ret) {
1827			if (genpd_is_cpu_domain(genpd))
1828				free_cpumask_var(genpd->cpus);
1829			return ret;
1830		}
1831	} else if (!gov && genpd->state_count > 1) {
1832		pr_warn("%s: no governor for states\n", genpd->name);
1833	}
1834
1835	device_initialize(&genpd->dev);
1836	dev_set_name(&genpd->dev, "%s", genpd->name);
 
1837
1838	mutex_lock(&gpd_list_lock);
1839	list_add(&genpd->gpd_list_node, &gpd_list);
1840	mutex_unlock(&gpd_list_lock);
1841
1842	return 0;
1843}
1844EXPORT_SYMBOL_GPL(pm_genpd_init);
1845
1846static int genpd_remove(struct generic_pm_domain *genpd)
1847{
1848	struct gpd_link *l, *link;
1849
1850	if (IS_ERR_OR_NULL(genpd))
1851		return -EINVAL;
1852
1853	genpd_lock(genpd);
1854
1855	if (genpd->has_provider) {
1856		genpd_unlock(genpd);
1857		pr_err("Provider present, unable to remove %s\n", genpd->name);
1858		return -EBUSY;
1859	}
1860
1861	if (!list_empty(&genpd->master_links) || genpd->device_count) {
1862		genpd_unlock(genpd);
1863		pr_err("%s: unable to remove %s\n", __func__, genpd->name);
1864		return -EBUSY;
1865	}
1866
1867	list_for_each_entry_safe(link, l, &genpd->slave_links, slave_node) {
1868		list_del(&link->master_node);
1869		list_del(&link->slave_node);
1870		kfree(link);
1871	}
1872
1873	list_del(&genpd->gpd_list_node);
1874	genpd_unlock(genpd);
1875	cancel_work_sync(&genpd->power_off_work);
1876	if (genpd_is_cpu_domain(genpd))
1877		free_cpumask_var(genpd->cpus);
1878	if (genpd->free_states)
1879		genpd->free_states(genpd->states, genpd->state_count);
1880
1881	pr_debug("%s: removed %s\n", __func__, genpd->name);
1882
1883	return 0;
1884}
1885
1886/**
1887 * pm_genpd_remove - Remove a generic I/O PM domain
1888 * @genpd: Pointer to PM domain that is to be removed.
1889 *
1890 * To remove the PM domain, this function:
1891 *  - Removes the PM domain as a subdomain to any parent domains,
1892 *    if it was added.
1893 *  - Removes the PM domain from the list of registered PM domains.
1894 *
1895 * The PM domain will only be removed, if the associated provider has
1896 * been removed, it is not a parent to any other PM domain and has no
1897 * devices associated with it.
1898 */
1899int pm_genpd_remove(struct generic_pm_domain *genpd)
1900{
1901	int ret;
1902
1903	mutex_lock(&gpd_list_lock);
1904	ret = genpd_remove(genpd);
1905	mutex_unlock(&gpd_list_lock);
1906
1907	return ret;
1908}
1909EXPORT_SYMBOL_GPL(pm_genpd_remove);
1910
1911#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
1912
1913/*
1914 * Device Tree based PM domain providers.
1915 *
1916 * The code below implements generic device tree based PM domain providers that
1917 * bind device tree nodes with generic PM domains registered in the system.
1918 *
1919 * Any driver that registers generic PM domains and needs to support binding of
1920 * devices to these domains is supposed to register a PM domain provider, which
1921 * maps a PM domain specifier retrieved from the device tree to a PM domain.
1922 *
1923 * Two simple mapping functions have been provided for convenience:
1924 *  - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
1925 *  - genpd_xlate_onecell() for mapping of multiple PM domains per node by
1926 *    index.
1927 */
1928
1929/**
1930 * struct of_genpd_provider - PM domain provider registration structure
1931 * @link: Entry in global list of PM domain providers
1932 * @node: Pointer to device tree node of PM domain provider
1933 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
1934 *         into a PM domain.
1935 * @data: context pointer to be passed into @xlate callback
1936 */
1937struct of_genpd_provider {
1938	struct list_head link;
1939	struct device_node *node;
1940	genpd_xlate_t xlate;
1941	void *data;
1942};
1943
1944/* List of registered PM domain providers. */
1945static LIST_HEAD(of_genpd_providers);
1946/* Mutex to protect the list above. */
1947static DEFINE_MUTEX(of_genpd_mutex);
1948
1949/**
1950 * genpd_xlate_simple() - Xlate function for direct node-domain mapping
1951 * @genpdspec: OF phandle args to map into a PM domain
1952 * @data: xlate function private data - pointer to struct generic_pm_domain
1953 *
1954 * This is a generic xlate function that can be used to model PM domains that
1955 * have their own device tree nodes. The private data of xlate function needs
1956 * to be a valid pointer to struct generic_pm_domain.
1957 */
1958static struct generic_pm_domain *genpd_xlate_simple(
1959					struct of_phandle_args *genpdspec,
1960					void *data)
1961{
 
 
1962	return data;
1963}
 
1964
1965/**
1966 * genpd_xlate_onecell() - Xlate function using a single index.
1967 * @genpdspec: OF phandle args to map into a PM domain
1968 * @data: xlate function private data - pointer to struct genpd_onecell_data
1969 *
1970 * This is a generic xlate function that can be used to model simple PM domain
1971 * controllers that have one device tree node and provide multiple PM domains.
1972 * A single cell is used as an index into an array of PM domains specified in
1973 * the genpd_onecell_data struct when registering the provider.
1974 */
1975static struct generic_pm_domain *genpd_xlate_onecell(
1976					struct of_phandle_args *genpdspec,
1977					void *data)
1978{
1979	struct genpd_onecell_data *genpd_data = data;
1980	unsigned int idx = genpdspec->args[0];
1981
1982	if (genpdspec->args_count != 1)
1983		return ERR_PTR(-EINVAL);
1984
1985	if (idx >= genpd_data->num_domains) {
1986		pr_err("%s: invalid domain index %u\n", __func__, idx);
1987		return ERR_PTR(-EINVAL);
1988	}
1989
1990	if (!genpd_data->domains[idx])
1991		return ERR_PTR(-ENOENT);
1992
1993	return genpd_data->domains[idx];
1994}
 
1995
1996/**
1997 * genpd_add_provider() - Register a PM domain provider for a node
1998 * @np: Device node pointer associated with the PM domain provider.
1999 * @xlate: Callback for decoding PM domain from phandle arguments.
2000 * @data: Context pointer for @xlate callback.
2001 */
2002static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
2003			      void *data)
2004{
2005	struct of_genpd_provider *cp;
2006
2007	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
2008	if (!cp)
2009		return -ENOMEM;
2010
2011	cp->node = of_node_get(np);
2012	cp->data = data;
2013	cp->xlate = xlate;
2014
2015	mutex_lock(&of_genpd_mutex);
2016	list_add(&cp->link, &of_genpd_providers);
2017	mutex_unlock(&of_genpd_mutex);
2018	pr_debug("Added domain provider from %pOF\n", np);
2019
2020	return 0;
2021}
2022
2023/**
2024 * of_genpd_add_provider_simple() - Register a simple PM domain provider
2025 * @np: Device node pointer associated with the PM domain provider.
2026 * @genpd: Pointer to PM domain associated with the PM domain provider.
2027 */
2028int of_genpd_add_provider_simple(struct device_node *np,
2029				 struct generic_pm_domain *genpd)
2030{
2031	int ret = -EINVAL;
2032
2033	if (!np || !genpd)
2034		return -EINVAL;
2035
2036	mutex_lock(&gpd_list_lock);
2037
2038	if (!genpd_present(genpd))
2039		goto unlock;
2040
2041	genpd->dev.of_node = np;
2042
2043	/* Parse genpd OPP table */
2044	if (genpd->set_performance_state) {
2045		ret = dev_pm_opp_of_add_table(&genpd->dev);
2046		if (ret) {
2047			dev_err(&genpd->dev, "Failed to add OPP table: %d\n",
2048				ret);
2049			goto unlock;
2050		}
2051
2052		/*
2053		 * Save table for faster processing while setting performance
2054		 * state.
2055		 */
2056		genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2057		WARN_ON(!genpd->opp_table);
2058	}
2059
2060	ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
2061	if (ret) {
2062		if (genpd->set_performance_state) {
2063			dev_pm_opp_put_opp_table(genpd->opp_table);
2064			dev_pm_opp_of_remove_table(&genpd->dev);
2065		}
2066
2067		goto unlock;
2068	}
2069
2070	genpd->provider = &np->fwnode;
2071	genpd->has_provider = true;
2072
2073unlock:
2074	mutex_unlock(&gpd_list_lock);
2075
2076	return ret;
2077}
2078EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
2079
2080/**
2081 * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
2082 * @np: Device node pointer associated with the PM domain provider.
2083 * @data: Pointer to the data associated with the PM domain provider.
2084 */
2085int of_genpd_add_provider_onecell(struct device_node *np,
2086				  struct genpd_onecell_data *data)
2087{
2088	struct generic_pm_domain *genpd;
2089	unsigned int i;
2090	int ret = -EINVAL;
2091
2092	if (!np || !data)
2093		return -EINVAL;
2094
2095	mutex_lock(&gpd_list_lock);
2096
2097	if (!data->xlate)
2098		data->xlate = genpd_xlate_onecell;
2099
2100	for (i = 0; i < data->num_domains; i++) {
2101		genpd = data->domains[i];
2102
2103		if (!genpd)
2104			continue;
2105		if (!genpd_present(genpd))
2106			goto error;
2107
2108		genpd->dev.of_node = np;
2109
2110		/* Parse genpd OPP table */
2111		if (genpd->set_performance_state) {
2112			ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
2113			if (ret) {
2114				dev_err(&genpd->dev, "Failed to add OPP table for index %d: %d\n",
2115					i, ret);
2116				goto error;
2117			}
2118
2119			/*
2120			 * Save table for faster processing while setting
2121			 * performance state.
2122			 */
2123			genpd->opp_table = dev_pm_opp_get_opp_table_indexed(&genpd->dev, i);
2124			WARN_ON(!genpd->opp_table);
2125		}
2126
2127		genpd->provider = &np->fwnode;
2128		genpd->has_provider = true;
2129	}
2130
2131	ret = genpd_add_provider(np, data->xlate, data);
2132	if (ret < 0)
2133		goto error;
2134
2135	mutex_unlock(&gpd_list_lock);
2136
2137	return 0;
2138
2139error:
2140	while (i--) {
2141		genpd = data->domains[i];
2142
2143		if (!genpd)
2144			continue;
2145
2146		genpd->provider = NULL;
2147		genpd->has_provider = false;
2148
2149		if (genpd->set_performance_state) {
2150			dev_pm_opp_put_opp_table(genpd->opp_table);
2151			dev_pm_opp_of_remove_table(&genpd->dev);
2152		}
2153	}
2154
2155	mutex_unlock(&gpd_list_lock);
2156
2157	return ret;
2158}
2159EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
2160
2161/**
2162 * of_genpd_del_provider() - Remove a previously registered PM domain provider
2163 * @np: Device node pointer associated with the PM domain provider
2164 */
2165void of_genpd_del_provider(struct device_node *np)
2166{
2167	struct of_genpd_provider *cp, *tmp;
2168	struct generic_pm_domain *gpd;
2169
2170	mutex_lock(&gpd_list_lock);
2171	mutex_lock(&of_genpd_mutex);
2172	list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
2173		if (cp->node == np) {
2174			/*
2175			 * For each PM domain associated with the
2176			 * provider, set the 'has_provider' to false
2177			 * so that the PM domain can be safely removed.
2178			 */
2179			list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2180				if (gpd->provider == &np->fwnode) {
2181					gpd->has_provider = false;
2182
2183					if (!gpd->set_performance_state)
2184						continue;
2185
2186					dev_pm_opp_put_opp_table(gpd->opp_table);
2187					dev_pm_opp_of_remove_table(&gpd->dev);
2188				}
2189			}
2190
2191			list_del(&cp->link);
2192			of_node_put(cp->node);
2193			kfree(cp);
2194			break;
2195		}
2196	}
2197	mutex_unlock(&of_genpd_mutex);
2198	mutex_unlock(&gpd_list_lock);
2199}
2200EXPORT_SYMBOL_GPL(of_genpd_del_provider);
2201
2202/**
2203 * genpd_get_from_provider() - Look-up PM domain
2204 * @genpdspec: OF phandle args to use for look-up
2205 *
2206 * Looks for a PM domain provider under the node specified by @genpdspec and if
2207 * found, uses xlate function of the provider to map phandle args to a PM
2208 * domain.
2209 *
2210 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
2211 * on failure.
2212 */
2213static struct generic_pm_domain *genpd_get_from_provider(
2214					struct of_phandle_args *genpdspec)
2215{
2216	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
2217	struct of_genpd_provider *provider;
2218
2219	if (!genpdspec)
2220		return ERR_PTR(-EINVAL);
2221
2222	mutex_lock(&of_genpd_mutex);
2223
2224	/* Check if we have such a provider in our array */
2225	list_for_each_entry(provider, &of_genpd_providers, link) {
2226		if (provider->node == genpdspec->np)
2227			genpd = provider->xlate(genpdspec, provider->data);
2228		if (!IS_ERR(genpd))
2229			break;
2230	}
2231
2232	mutex_unlock(&of_genpd_mutex);
2233
2234	return genpd;
2235}
2236
2237/**
2238 * of_genpd_add_device() - Add a device to an I/O PM domain
2239 * @genpdspec: OF phandle args to use for look-up PM domain
2240 * @dev: Device to be added.
2241 *
2242 * Looks-up an I/O PM domain based upon phandle args provided and adds
2243 * the device to the PM domain. Returns a negative error code on failure.
2244 */
2245int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
2246{
2247	struct generic_pm_domain *genpd;
2248	int ret;
2249
2250	mutex_lock(&gpd_list_lock);
2251
2252	genpd = genpd_get_from_provider(genpdspec);
2253	if (IS_ERR(genpd)) {
2254		ret = PTR_ERR(genpd);
2255		goto out;
2256	}
2257
2258	ret = genpd_add_device(genpd, dev, dev);
2259
2260out:
2261	mutex_unlock(&gpd_list_lock);
2262
2263	return ret;
2264}
2265EXPORT_SYMBOL_GPL(of_genpd_add_device);
2266
2267/**
2268 * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
2269 * @parent_spec: OF phandle args to use for parent PM domain look-up
2270 * @subdomain_spec: OF phandle args to use for subdomain look-up
2271 *
2272 * Looks-up a parent PM domain and subdomain based upon phandle args
2273 * provided and adds the subdomain to the parent PM domain. Returns a
2274 * negative error code on failure.
2275 */
2276int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
2277			   struct of_phandle_args *subdomain_spec)
2278{
2279	struct generic_pm_domain *parent, *subdomain;
2280	int ret;
2281
2282	mutex_lock(&gpd_list_lock);
2283
2284	parent = genpd_get_from_provider(parent_spec);
2285	if (IS_ERR(parent)) {
2286		ret = PTR_ERR(parent);
2287		goto out;
2288	}
2289
2290	subdomain = genpd_get_from_provider(subdomain_spec);
2291	if (IS_ERR(subdomain)) {
2292		ret = PTR_ERR(subdomain);
2293		goto out;
2294	}
2295
2296	ret = genpd_add_subdomain(parent, subdomain);
2297
2298out:
2299	mutex_unlock(&gpd_list_lock);
2300
2301	return ret;
2302}
2303EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
2304
2305/**
2306 * of_genpd_remove_last - Remove the last PM domain registered for a provider
2307 * @provider: Pointer to device structure associated with provider
2308 *
2309 * Find the last PM domain that was added by a particular provider and
2310 * remove this PM domain from the list of PM domains. The provider is
2311 * identified by the 'provider' device structure that is passed. The PM
2312 * domain will only be removed, if the provider associated with domain
2313 * has been removed.
2314 *
2315 * Returns a valid pointer to struct generic_pm_domain on success or
2316 * ERR_PTR() on failure.
2317 */
2318struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
2319{
2320	struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
2321	int ret;
2322
2323	if (IS_ERR_OR_NULL(np))
2324		return ERR_PTR(-EINVAL);
2325
2326	mutex_lock(&gpd_list_lock);
2327	list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
2328		if (gpd->provider == &np->fwnode) {
2329			ret = genpd_remove(gpd);
2330			genpd = ret ? ERR_PTR(ret) : gpd;
2331			break;
2332		}
2333	}
2334	mutex_unlock(&gpd_list_lock);
2335
2336	return genpd;
2337}
2338EXPORT_SYMBOL_GPL(of_genpd_remove_last);
2339
2340static void genpd_release_dev(struct device *dev)
2341{
2342	of_node_put(dev->of_node);
2343	kfree(dev);
2344}
2345
2346static struct bus_type genpd_bus_type = {
2347	.name		= "genpd",
2348};
2349
2350/**
2351 * genpd_dev_pm_detach - Detach a device from its PM domain.
2352 * @dev: Device to detach.
2353 * @power_off: Currently not used
2354 *
2355 * Try to locate a corresponding generic PM domain, which the device was
2356 * attached to previously. If such is found, the device is detached from it.
2357 */
2358static void genpd_dev_pm_detach(struct device *dev, bool power_off)
2359{
2360	struct generic_pm_domain *pd;
2361	unsigned int i;
2362	int ret = 0;
2363
2364	pd = dev_to_genpd(dev);
2365	if (IS_ERR(pd))
2366		return;
2367
2368	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
2369
2370	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2371		ret = genpd_remove_device(pd, dev);
2372		if (ret != -EAGAIN)
2373			break;
2374
2375		mdelay(i);
2376		cond_resched();
2377	}
2378
2379	if (ret < 0) {
2380		dev_err(dev, "failed to remove from PM domain %s: %d",
2381			pd->name, ret);
2382		return;
2383	}
2384
2385	/* Check if PM domain can be powered off after removing this device. */
2386	genpd_queue_power_off_work(pd);
2387
2388	/* Unregister the device if it was created by genpd. */
2389	if (dev->bus == &genpd_bus_type)
2390		device_unregister(dev);
2391}
2392
2393static void genpd_dev_pm_sync(struct device *dev)
2394{
2395	struct generic_pm_domain *pd;
2396
2397	pd = dev_to_genpd(dev);
2398	if (IS_ERR(pd))
2399		return;
2400
2401	genpd_queue_power_off_work(pd);
2402}
2403
2404static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
2405				 unsigned int index, bool power_on)
2406{
2407	struct of_phandle_args pd_args;
2408	struct generic_pm_domain *pd;
2409	int ret;
2410
2411	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
2412				"#power-domain-cells", index, &pd_args);
2413	if (ret < 0)
2414		return ret;
2415
2416	mutex_lock(&gpd_list_lock);
2417	pd = genpd_get_from_provider(&pd_args);
2418	of_node_put(pd_args.np);
2419	if (IS_ERR(pd)) {
2420		mutex_unlock(&gpd_list_lock);
2421		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
2422			__func__, PTR_ERR(pd));
2423		return driver_deferred_probe_check_state(base_dev);
2424	}
2425
2426	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
2427
2428	ret = genpd_add_device(pd, dev, base_dev);
2429	mutex_unlock(&gpd_list_lock);
2430
2431	if (ret < 0) {
2432		if (ret != -EPROBE_DEFER)
2433			dev_err(dev, "failed to add to PM domain %s: %d",
2434				pd->name, ret);
2435		return ret;
2436	}
2437
2438	dev->pm_domain->detach = genpd_dev_pm_detach;
2439	dev->pm_domain->sync = genpd_dev_pm_sync;
2440
2441	if (power_on) {
2442		genpd_lock(pd);
2443		ret = genpd_power_on(pd, 0);
2444		genpd_unlock(pd);
2445	}
2446
2447	if (ret)
2448		genpd_remove_device(pd, dev);
2449
2450	return ret ? -EPROBE_DEFER : 1;
2451}
2452
2453/**
2454 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
2455 * @dev: Device to attach.
2456 *
2457 * Parse device's OF node to find a PM domain specifier. If such is found,
2458 * attaches the device to retrieved pm_domain ops.
2459 *
2460 * Returns 1 on successfully attached PM domain, 0 when the device don't need a
2461 * PM domain or when multiple power-domains exists for it, else a negative error
2462 * code. Note that if a power-domain exists for the device, but it cannot be
2463 * found or turned on, then return -EPROBE_DEFER to ensure that the device is
2464 * not probed and to re-try again later.
 
 
2465 */
2466int genpd_dev_pm_attach(struct device *dev)
2467{
2468	if (!dev->of_node)
2469		return 0;
2470
2471	/*
2472	 * Devices with multiple PM domains must be attached separately, as we
2473	 * can only attach one PM domain per device.
2474	 */
2475	if (of_count_phandle_with_args(dev->of_node, "power-domains",
2476				       "#power-domain-cells") != 1)
2477		return 0;
2478
2479	return __genpd_dev_pm_attach(dev, dev, 0, true);
2480}
2481EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
2482
2483/**
2484 * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
2485 * @dev: The device used to lookup the PM domain.
2486 * @index: The index of the PM domain.
2487 *
2488 * Parse device's OF node to find a PM domain specifier at the provided @index.
2489 * If such is found, creates a virtual device and attaches it to the retrieved
2490 * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
2491 * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
2492 *
2493 * Returns the created virtual device if successfully attached PM domain, NULL
2494 * when the device don't need a PM domain, else an ERR_PTR() in case of
2495 * failures. If a power-domain exists for the device, but cannot be found or
2496 * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
2497 * is not probed and to re-try again later.
2498 */
2499struct device *genpd_dev_pm_attach_by_id(struct device *dev,
2500					 unsigned int index)
2501{
2502	struct device *virt_dev;
2503	int num_domains;
2504	int ret;
2505
2506	if (!dev->of_node)
2507		return NULL;
2508
2509	/* Verify that the index is within a valid range. */
2510	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
2511						 "#power-domain-cells");
2512	if (index >= num_domains)
2513		return NULL;
2514
2515	/* Allocate and register device on the genpd bus. */
2516	virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
2517	if (!virt_dev)
2518		return ERR_PTR(-ENOMEM);
2519
2520	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
2521	virt_dev->bus = &genpd_bus_type;
2522	virt_dev->release = genpd_release_dev;
2523	virt_dev->of_node = of_node_get(dev->of_node);
2524
2525	ret = device_register(virt_dev);
2526	if (ret) {
2527		put_device(virt_dev);
2528		return ERR_PTR(ret);
2529	}
2530
2531	/* Try to attach the device to the PM domain at the specified index. */
2532	ret = __genpd_dev_pm_attach(virt_dev, dev, index, false);
2533	if (ret < 1) {
2534		device_unregister(virt_dev);
2535		return ret ? ERR_PTR(ret) : NULL;
2536	}
2537
2538	pm_runtime_enable(virt_dev);
2539	genpd_queue_power_off_work(dev_to_genpd(virt_dev));
2540
2541	return virt_dev;
2542}
2543EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
2544
2545/**
2546 * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
2547 * @dev: The device used to lookup the PM domain.
2548 * @name: The name of the PM domain.
2549 *
2550 * Parse device's OF node to find a PM domain specifier using the
2551 * power-domain-names DT property. For further description see
2552 * genpd_dev_pm_attach_by_id().
2553 */
2554struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
2555{
2556	int index;
2557
2558	if (!dev->of_node)
2559		return NULL;
2560
2561	index = of_property_match_string(dev->of_node, "power-domain-names",
2562					 name);
2563	if (index < 0)
2564		return NULL;
2565
2566	return genpd_dev_pm_attach_by_id(dev, index);
2567}
2568
2569static const struct of_device_id idle_state_match[] = {
2570	{ .compatible = "domain-idle-state", },
2571	{ }
2572};
2573
2574static int genpd_parse_state(struct genpd_power_state *genpd_state,
2575				    struct device_node *state_node)
2576{
2577	int err;
2578	u32 residency;
2579	u32 entry_latency, exit_latency;
2580
2581	err = of_property_read_u32(state_node, "entry-latency-us",
2582						&entry_latency);
2583	if (err) {
2584		pr_debug(" * %pOF missing entry-latency-us property\n",
2585			 state_node);
2586		return -EINVAL;
2587	}
2588
2589	err = of_property_read_u32(state_node, "exit-latency-us",
2590						&exit_latency);
2591	if (err) {
2592		pr_debug(" * %pOF missing exit-latency-us property\n",
2593			 state_node);
2594		return -EINVAL;
 
 
 
2595	}
2596
2597	err = of_property_read_u32(state_node, "min-residency-us", &residency);
2598	if (!err)
2599		genpd_state->residency_ns = 1000 * residency;
2600
2601	genpd_state->power_on_latency_ns = 1000 * exit_latency;
2602	genpd_state->power_off_latency_ns = 1000 * entry_latency;
2603	genpd_state->fwnode = &state_node->fwnode;
2604
2605	return 0;
2606}
2607
2608static int genpd_iterate_idle_states(struct device_node *dn,
2609				     struct genpd_power_state *states)
2610{
2611	int ret;
2612	struct of_phandle_iterator it;
2613	struct device_node *np;
2614	int i = 0;
2615
2616	ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
2617	if (ret <= 0)
2618		return ret;
2619
2620	/* Loop over the phandles until all the requested entry is found */
2621	of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
2622		np = it.node;
2623		if (!of_match_node(idle_state_match, np))
2624			continue;
2625		if (states) {
2626			ret = genpd_parse_state(&states[i], np);
2627			if (ret) {
2628				pr_err("Parsing idle state node %pOF failed with err %d\n",
2629				       np, ret);
2630				of_node_put(np);
2631				return ret;
2632			}
2633		}
2634		i++;
2635	}
2636
2637	return i;
2638}
2639
2640/**
2641 * of_genpd_parse_idle_states: Return array of idle states for the genpd.
2642 *
2643 * @dn: The genpd device node
2644 * @states: The pointer to which the state array will be saved.
2645 * @n: The count of elements in the array returned from this function.
2646 *
2647 * Returns the device states parsed from the OF node. The memory for the states
2648 * is allocated by this function and is the responsibility of the caller to
2649 * free the memory after use. If any or zero compatible domain idle states is
2650 * found it returns 0 and in case of errors, a negative error code is returned.
2651 */
2652int of_genpd_parse_idle_states(struct device_node *dn,
2653			struct genpd_power_state **states, int *n)
2654{
2655	struct genpd_power_state *st;
2656	int ret;
2657
2658	ret = genpd_iterate_idle_states(dn, NULL);
2659	if (ret < 0)
2660		return ret;
 
2661
2662	if (!ret) {
2663		*states = NULL;
2664		*n = 0;
2665		return 0;
2666	}
2667
2668	st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
2669	if (!st)
2670		return -ENOMEM;
2671
2672	ret = genpd_iterate_idle_states(dn, st);
2673	if (ret <= 0) {
2674		kfree(st);
2675		return ret < 0 ? ret : -EINVAL;
2676	}
2677
2678	*states = st;
2679	*n = ret;
2680
2681	return 0;
2682}
2683EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
2684
2685/**
2686 * pm_genpd_opp_to_performance_state - Gets performance state of the genpd from its OPP node.
2687 *
2688 * @genpd_dev: Genpd's device for which the performance-state needs to be found.
2689 * @opp: struct dev_pm_opp of the OPP for which we need to find performance
2690 *	state.
2691 *
2692 * Returns performance state encoded in the OPP of the genpd. This calls
2693 * platform specific genpd->opp_to_performance_state() callback to translate
2694 * power domain OPP to performance state.
2695 *
2696 * Returns performance state on success and 0 on failure.
2697 */
2698unsigned int pm_genpd_opp_to_performance_state(struct device *genpd_dev,
2699					       struct dev_pm_opp *opp)
2700{
2701	struct generic_pm_domain *genpd = NULL;
2702	int state;
2703
2704	genpd = container_of(genpd_dev, struct generic_pm_domain, dev);
2705
2706	if (unlikely(!genpd->opp_to_performance_state))
2707		return 0;
2708
2709	genpd_lock(genpd);
2710	state = genpd->opp_to_performance_state(genpd, opp);
2711	genpd_unlock(genpd);
2712
2713	return state;
2714}
2715EXPORT_SYMBOL_GPL(pm_genpd_opp_to_performance_state);
2716
2717static int __init genpd_bus_init(void)
2718{
2719	return bus_register(&genpd_bus_type);
 
 
2720}
2721core_initcall(genpd_bus_init);
2722
2723#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
2724
2725
2726/***        debugfs support        ***/
2727
2728#ifdef CONFIG_DEBUG_FS
2729#include <linux/pm.h>
2730#include <linux/device.h>
2731#include <linux/debugfs.h>
2732#include <linux/seq_file.h>
2733#include <linux/init.h>
2734#include <linux/kobject.h>
2735static struct dentry *genpd_debugfs_dir;
2736
2737/*
2738 * TODO: This function is a slightly modified version of rtpm_status_show
2739 * from sysfs.c, so generalize it.
2740 */
2741static void rtpm_status_str(struct seq_file *s, struct device *dev)
2742{
2743	static const char * const status_lookup[] = {
2744		[RPM_ACTIVE] = "active",
2745		[RPM_RESUMING] = "resuming",
2746		[RPM_SUSPENDED] = "suspended",
2747		[RPM_SUSPENDING] = "suspending"
2748	};
2749	const char *p = "";
2750
2751	if (dev->power.runtime_error)
2752		p = "error";
2753	else if (dev->power.disable_depth)
2754		p = "unsupported";
2755	else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
2756		p = status_lookup[dev->power.runtime_status];
2757	else
2758		WARN_ON(1);
2759
2760	seq_puts(s, p);
2761}
2762
2763static int genpd_summary_one(struct seq_file *s,
2764			struct generic_pm_domain *genpd)
2765{
2766	static const char * const status_lookup[] = {
2767		[GPD_STATE_ACTIVE] = "on",
2768		[GPD_STATE_POWER_OFF] = "off"
2769	};
2770	struct pm_domain_data *pm_data;
2771	const char *kobj_path;
2772	struct gpd_link *link;
2773	char state[16];
2774	int ret;
2775
2776	ret = genpd_lock_interruptible(genpd);
2777	if (ret)
2778		return -ERESTARTSYS;
2779
2780	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
2781		goto exit;
2782	if (!genpd_status_on(genpd))
2783		snprintf(state, sizeof(state), "%s-%u",
2784			 status_lookup[genpd->status], genpd->state_idx);
2785	else
2786		snprintf(state, sizeof(state), "%s",
2787			 status_lookup[genpd->status]);
2788	seq_printf(s, "%-30s  %-15s ", genpd->name, state);
2789
2790	/*
2791	 * Modifications on the list require holding locks on both
2792	 * master and slave, so we are safe.
2793	 * Also genpd->name is immutable.
2794	 */
2795	list_for_each_entry(link, &genpd->master_links, master_node) {
2796		seq_printf(s, "%s", link->slave->name);
2797		if (!list_is_last(&link->master_node, &genpd->master_links))
2798			seq_puts(s, ", ");
2799	}
2800
2801	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
2802		kobj_path = kobject_get_path(&pm_data->dev->kobj,
2803				genpd_is_irq_safe(genpd) ?
2804				GFP_ATOMIC : GFP_KERNEL);
2805		if (kobj_path == NULL)
2806			continue;
2807
2808		seq_printf(s, "\n    %-50s  ", kobj_path);
2809		rtpm_status_str(s, pm_data->dev);
2810		kfree(kobj_path);
2811	}
2812
2813	seq_puts(s, "\n");
2814exit:
2815	genpd_unlock(genpd);
2816
2817	return 0;
2818}
2819
2820static int summary_show(struct seq_file *s, void *data)
2821{
2822	struct generic_pm_domain *genpd;
2823	int ret = 0;
2824
2825	seq_puts(s, "domain                          status          slaves\n");
2826	seq_puts(s, "    /device                                             runtime status\n");
2827	seq_puts(s, "----------------------------------------------------------------------\n");
2828
2829	ret = mutex_lock_interruptible(&gpd_list_lock);
2830	if (ret)
2831		return -ERESTARTSYS;
2832
2833	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
2834		ret = genpd_summary_one(s, genpd);
2835		if (ret)
2836			break;
2837	}
2838	mutex_unlock(&gpd_list_lock);
2839
2840	return ret;
2841}
2842
2843static int status_show(struct seq_file *s, void *data)
2844{
2845	static const char * const status_lookup[] = {
2846		[GPD_STATE_ACTIVE] = "on",
2847		[GPD_STATE_POWER_OFF] = "off"
2848	};
2849
2850	struct generic_pm_domain *genpd = s->private;
2851	int ret = 0;
2852
2853	ret = genpd_lock_interruptible(genpd);
2854	if (ret)
2855		return -ERESTARTSYS;
2856
2857	if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
2858		goto exit;
2859
2860	if (genpd->status == GPD_STATE_POWER_OFF)
2861		seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
2862			genpd->state_idx);
2863	else
2864		seq_printf(s, "%s\n", status_lookup[genpd->status]);
2865exit:
2866	genpd_unlock(genpd);
2867	return ret;
2868}
2869
2870static int sub_domains_show(struct seq_file *s, void *data)
2871{
2872	struct generic_pm_domain *genpd = s->private;
2873	struct gpd_link *link;
2874	int ret = 0;
2875
2876	ret = genpd_lock_interruptible(genpd);
2877	if (ret)
2878		return -ERESTARTSYS;
2879
2880	list_for_each_entry(link, &genpd->master_links, master_node)
2881		seq_printf(s, "%s\n", link->slave->name);
2882
2883	genpd_unlock(genpd);
2884	return ret;
2885}
2886
2887static int idle_states_show(struct seq_file *s, void *data)
2888{
2889	struct generic_pm_domain *genpd = s->private;
2890	unsigned int i;
2891	int ret = 0;
2892
2893	ret = genpd_lock_interruptible(genpd);
2894	if (ret)
2895		return -ERESTARTSYS;
2896
2897	seq_puts(s, "State          Time Spent(ms)\n");
2898
2899	for (i = 0; i < genpd->state_count; i++) {
2900		ktime_t delta = 0;
2901		s64 msecs;
2902
2903		if ((genpd->status == GPD_STATE_POWER_OFF) &&
2904				(genpd->state_idx == i))
2905			delta = ktime_sub(ktime_get(), genpd->accounting_time);
2906
2907		msecs = ktime_to_ms(
2908			ktime_add(genpd->states[i].idle_time, delta));
2909		seq_printf(s, "S%-13i %lld\n", i, msecs);
2910	}
2911
2912	genpd_unlock(genpd);
2913	return ret;
2914}
2915
2916static int active_time_show(struct seq_file *s, void *data)
2917{
2918	struct generic_pm_domain *genpd = s->private;
2919	ktime_t delta = 0;
2920	int ret = 0;
2921
2922	ret = genpd_lock_interruptible(genpd);
2923	if (ret)
2924		return -ERESTARTSYS;
2925
2926	if (genpd->status == GPD_STATE_ACTIVE)
2927		delta = ktime_sub(ktime_get(), genpd->accounting_time);
2928
2929	seq_printf(s, "%lld ms\n", ktime_to_ms(
2930				ktime_add(genpd->on_time, delta)));
2931
2932	genpd_unlock(genpd);
2933	return ret;
2934}
2935
2936static int total_idle_time_show(struct seq_file *s, void *data)
2937{
2938	struct generic_pm_domain *genpd = s->private;
2939	ktime_t delta = 0, total = 0;
2940	unsigned int i;
2941	int ret = 0;
2942
2943	ret = genpd_lock_interruptible(genpd);
2944	if (ret)
2945		return -ERESTARTSYS;
2946
2947	for (i = 0; i < genpd->state_count; i++) {
2948
2949		if ((genpd->status == GPD_STATE_POWER_OFF) &&
2950				(genpd->state_idx == i))
2951			delta = ktime_sub(ktime_get(), genpd->accounting_time);
2952
2953		total = ktime_add(total, genpd->states[i].idle_time);
2954	}
2955	total = ktime_add(total, delta);
2956
2957	seq_printf(s, "%lld ms\n", ktime_to_ms(total));
2958
2959	genpd_unlock(genpd);
2960	return ret;
2961}
2962
 
 
 
 
 
 
2963
2964static int devices_show(struct seq_file *s, void *data)
2965{
2966	struct generic_pm_domain *genpd = s->private;
2967	struct pm_domain_data *pm_data;
2968	const char *kobj_path;
2969	int ret = 0;
2970
2971	ret = genpd_lock_interruptible(genpd);
2972	if (ret)
2973		return -ERESTARTSYS;
2974
2975	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
2976		kobj_path = kobject_get_path(&pm_data->dev->kobj,
2977				genpd_is_irq_safe(genpd) ?
2978				GFP_ATOMIC : GFP_KERNEL);
2979		if (kobj_path == NULL)
2980			continue;
2981
2982		seq_printf(s, "%s\n", kobj_path);
2983		kfree(kobj_path);
2984	}
2985
2986	genpd_unlock(genpd);
2987	return ret;
2988}
2989
2990static int perf_state_show(struct seq_file *s, void *data)
2991{
2992	struct generic_pm_domain *genpd = s->private;
2993
2994	if (genpd_lock_interruptible(genpd))
2995		return -ERESTARTSYS;
2996
2997	seq_printf(s, "%u\n", genpd->performance_state);
2998
2999	genpd_unlock(genpd);
3000	return 0;
3001}
3002
3003DEFINE_SHOW_ATTRIBUTE(summary);
3004DEFINE_SHOW_ATTRIBUTE(status);
3005DEFINE_SHOW_ATTRIBUTE(sub_domains);
3006DEFINE_SHOW_ATTRIBUTE(idle_states);
3007DEFINE_SHOW_ATTRIBUTE(active_time);
3008DEFINE_SHOW_ATTRIBUTE(total_idle_time);
3009DEFINE_SHOW_ATTRIBUTE(devices);
3010DEFINE_SHOW_ATTRIBUTE(perf_state);
3011
3012static int __init genpd_debug_init(void)
3013{
3014	struct dentry *d;
3015	struct generic_pm_domain *genpd;
3016
3017	genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
3018
3019	debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
3020			    NULL, &summary_fops);
3021
3022	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
3023		d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
3024
3025		debugfs_create_file("current_state", 0444,
3026				d, genpd, &status_fops);
3027		debugfs_create_file("sub_domains", 0444,
3028				d, genpd, &sub_domains_fops);
3029		debugfs_create_file("idle_states", 0444,
3030				d, genpd, &idle_states_fops);
3031		debugfs_create_file("active_time", 0444,
3032				d, genpd, &active_time_fops);
3033		debugfs_create_file("total_idle_time", 0444,
3034				d, genpd, &total_idle_time_fops);
3035		debugfs_create_file("devices", 0444,
3036				d, genpd, &devices_fops);
3037		if (genpd->set_performance_state)
3038			debugfs_create_file("perf_state", 0444,
3039					    d, genpd, &perf_state_fops);
3040	}
3041
3042	return 0;
3043}
3044late_initcall(genpd_debug_init);
3045
3046static void __exit genpd_debug_exit(void)
3047{
3048	debugfs_remove_recursive(genpd_debugfs_dir);
3049}
3050__exitcall(genpd_debug_exit);
3051#endif /* CONFIG_DEBUG_FS */
v4.6
 
   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/delay.h>
  10#include <linux/kernel.h>
  11#include <linux/io.h>
  12#include <linux/platform_device.h>
 
  13#include <linux/pm_runtime.h>
  14#include <linux/pm_domain.h>
  15#include <linux/pm_qos.h>
  16#include <linux/pm_clock.h>
  17#include <linux/slab.h>
  18#include <linux/err.h>
  19#include <linux/sched.h>
  20#include <linux/suspend.h>
  21#include <linux/export.h>
 
  22
  23#include "power.h"
  24
  25#define GENPD_RETRY_MAX_MS	250		/* Approximate */
  26
  27#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)		\
  28({								\
  29	type (*__routine)(struct device *__d); 			\
  30	type __ret = (type)0;					\
  31								\
  32	__routine = genpd->dev_ops.callback; 			\
  33	if (__routine) {					\
  34		__ret = __routine(dev); 			\
  35	}							\
  36	__ret;							\
  37})
  38
  39static LIST_HEAD(gpd_list);
  40static DEFINE_MUTEX(gpd_list_lock);
  41
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  42/*
  43 * Get the generic PM domain for a particular struct device.
  44 * This validates the struct device pointer, the PM domain pointer,
  45 * and checks that the PM domain pointer is a real generic PM domain.
  46 * Any failure results in NULL being returned.
  47 */
  48struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
  49{
  50	struct generic_pm_domain *genpd = NULL, *gpd;
  51
  52	if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
  53		return NULL;
  54
  55	mutex_lock(&gpd_list_lock);
  56	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
  57		if (&gpd->domain == dev->pm_domain) {
  58			genpd = gpd;
  59			break;
  60		}
  61	}
  62	mutex_unlock(&gpd_list_lock);
  63
  64	return genpd;
  65}
  66
  67/*
  68 * This should only be used where we are certain that the pm_domain
  69 * attached to the device is a genpd domain.
  70 */
  71static struct generic_pm_domain *dev_to_genpd(struct device *dev)
  72{
  73	if (IS_ERR_OR_NULL(dev->pm_domain))
  74		return ERR_PTR(-EINVAL);
  75
  76	return pd_to_genpd(dev->pm_domain);
  77}
  78
  79static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
 
  80{
  81	return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
  82}
  83
  84static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
 
  85{
  86	return GENPD_DEV_CALLBACK(genpd, int, start, dev);
  87}
  88
  89static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
  90{
  91	bool ret = false;
  92
  93	if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
  94		ret = !!atomic_dec_and_test(&genpd->sd_count);
  95
  96	return ret;
  97}
  98
  99static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 100{
 101	atomic_inc(&genpd->sd_count);
 102	smp_mb__after_atomic();
 103}
 104
 105static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 106{
 107	unsigned int state_idx = genpd->state_idx;
 108	ktime_t time_start;
 109	s64 elapsed_ns;
 110	int ret;
 111
 112	if (!genpd->power_on)
 113		return 0;
 114
 115	if (!timed)
 116		return genpd->power_on(genpd);
 117
 118	time_start = ktime_get();
 119	ret = genpd->power_on(genpd);
 120	if (ret)
 121		return ret;
 122
 123	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 124	if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
 125		return ret;
 126
 127	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
 128	genpd->max_off_time_changed = true;
 129	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 130		 genpd->name, "on", elapsed_ns);
 131
 132	return ret;
 133}
 134
 135static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 136{
 137	unsigned int state_idx = genpd->state_idx;
 138	ktime_t time_start;
 139	s64 elapsed_ns;
 140	int ret;
 141
 142	if (!genpd->power_off)
 143		return 0;
 144
 145	if (!timed)
 146		return genpd->power_off(genpd);
 147
 148	time_start = ktime_get();
 149	ret = genpd->power_off(genpd);
 150	if (ret == -EBUSY)
 151		return ret;
 152
 153	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 154	if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
 155		return ret;
 156
 157	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
 158	genpd->max_off_time_changed = true;
 159	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 160		 genpd->name, "off", elapsed_ns);
 161
 162	return ret;
 163}
 164
 165/**
 166 * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
 167 * @genpd: PM domain to power off.
 168 *
 169 * Queue up the execution of genpd_poweroff() unless it's already been done
 170 * before.
 171 */
 172static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 173{
 174	queue_work(pm_wq, &genpd->power_off_work);
 175}
 176
 177/**
 178 * genpd_poweron - Restore power to a given PM domain and its masters.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 179 * @genpd: PM domain to power up.
 180 * @depth: nesting count for lockdep.
 181 *
 182 * Restore power to @genpd and all of its masters so that it is possible to
 183 * resume a device belonging to it.
 184 */
 185static int genpd_poweron(struct generic_pm_domain *genpd, unsigned int depth)
 186{
 187	struct gpd_link *link;
 188	int ret = 0;
 189
 190	if (genpd->status == GPD_STATE_ACTIVE
 191	    || (genpd->prepared_count > 0 && genpd->suspend_power_off))
 192		return 0;
 193
 194	/*
 195	 * The list is guaranteed not to change while the loop below is being
 196	 * executed, unless one of the masters' .power_on() callbacks fiddles
 197	 * with it.
 198	 */
 199	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 200		struct generic_pm_domain *master = link->master;
 201
 202		genpd_sd_counter_inc(master);
 203
 204		mutex_lock_nested(&master->lock, depth + 1);
 205		ret = genpd_poweron(master, depth + 1);
 206		mutex_unlock(&master->lock);
 207
 208		if (ret) {
 209			genpd_sd_counter_dec(master);
 210			goto err;
 211		}
 212	}
 213
 214	ret = genpd_power_on(genpd, true);
 215	if (ret)
 216		goto err;
 217
 218	genpd->status = GPD_STATE_ACTIVE;
 
 
 219	return 0;
 220
 221 err:
 222	list_for_each_entry_continue_reverse(link,
 223					&genpd->slave_links,
 224					slave_node) {
 225		genpd_sd_counter_dec(link->master);
 226		genpd_queue_power_off_work(link->master);
 
 
 227	}
 228
 229	return ret;
 230}
 231
 232static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
 233{
 234	return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
 235}
 236
 237static int genpd_restore_dev(struct generic_pm_domain *genpd,
 238			struct device *dev)
 239{
 240	return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev);
 241}
 242
 243static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 244				     unsigned long val, void *ptr)
 245{
 246	struct generic_pm_domain_data *gpd_data;
 247	struct device *dev;
 248
 249	gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
 250	dev = gpd_data->base.dev;
 251
 252	for (;;) {
 253		struct generic_pm_domain *genpd;
 254		struct pm_domain_data *pdd;
 255
 256		spin_lock_irq(&dev->power.lock);
 257
 258		pdd = dev->power.subsys_data ?
 259				dev->power.subsys_data->domain_data : NULL;
 260		if (pdd && pdd->dev) {
 261			to_gpd_data(pdd)->td.constraint_changed = true;
 262			genpd = dev_to_genpd(dev);
 263		} else {
 264			genpd = ERR_PTR(-ENODATA);
 265		}
 266
 267		spin_unlock_irq(&dev->power.lock);
 268
 269		if (!IS_ERR(genpd)) {
 270			mutex_lock(&genpd->lock);
 271			genpd->max_off_time_changed = true;
 272			mutex_unlock(&genpd->lock);
 273		}
 274
 275		dev = dev->parent;
 276		if (!dev || dev->power.ignore_children)
 277			break;
 278	}
 279
 280	return NOTIFY_DONE;
 281}
 282
 283/**
 284 * genpd_poweroff - Remove power from a given PM domain.
 285 * @genpd: PM domain to power down.
 286 * @is_async: PM domain is powered down from a scheduled work
 287 *
 288 * If all of the @genpd's devices have been suspended and all of its subdomains
 289 * have been powered down, remove power from @genpd.
 290 */
 291static int genpd_poweroff(struct generic_pm_domain *genpd, bool is_async)
 292{
 293	struct pm_domain_data *pdd;
 294	struct gpd_link *link;
 295	unsigned int not_suspended = 0;
 296
 297	/*
 298	 * Do not try to power off the domain in the following situations:
 299	 * (1) The domain is already in the "power off" state.
 300	 * (2) System suspend is in progress.
 301	 */
 302	if (genpd->status == GPD_STATE_POWER_OFF
 303	    || genpd->prepared_count > 0)
 304		return 0;
 305
 306	if (atomic_read(&genpd->sd_count) > 0)
 307		return -EBUSY;
 
 
 308
 309	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 310		enum pm_qos_flags_status stat;
 
 
 
 
 
 311
 312		stat = dev_pm_qos_flags(pdd->dev,
 313					PM_QOS_FLAG_NO_POWER_OFF
 314						| PM_QOS_FLAG_REMOTE_WAKEUP);
 315		if (stat > PM_QOS_FLAGS_NONE)
 316			return -EBUSY;
 
 
 
 317
 318		if (!pm_runtime_suspended(pdd->dev) || pdd->dev->power.irq_safe)
 319			not_suspended++;
 320	}
 321
 322	if (not_suspended > 1 || (not_suspended == 1 && is_async))
 323		return -EBUSY;
 324
 325	if (genpd->gov && genpd->gov->power_down_ok) {
 326		if (!genpd->gov->power_down_ok(&genpd->domain))
 327			return -EAGAIN;
 328	}
 329
 330	if (genpd->power_off) {
 331		int ret;
 332
 333		if (atomic_read(&genpd->sd_count) > 0)
 334			return -EBUSY;
 335
 336		/*
 337		 * If sd_count > 0 at this point, one of the subdomains hasn't
 338		 * managed to call genpd_poweron() for the master yet after
 339		 * incrementing it.  In that case genpd_poweron() will wait
 340		 * for us to drop the lock, so we can call .power_off() and let
 341		 * the genpd_poweron() restore power for us (this shouldn't
 342		 * happen very often).
 343		 */
 344		ret = genpd_power_off(genpd, true);
 345		if (ret)
 346			return ret;
 347	}
 348
 349	genpd->status = GPD_STATE_POWER_OFF;
 350
 351	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 352		genpd_sd_counter_dec(link->master);
 353		genpd_queue_power_off_work(link->master);
 354	}
 355
 356	return 0;
 357}
 358
 359/**
 360 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 361 * @work: Work structure used for scheduling the execution of this function.
 362 */
 363static void genpd_power_off_work_fn(struct work_struct *work)
 364{
 365	struct generic_pm_domain *genpd;
 
 
 
 
 
 
 
 
 
 366
 367	genpd = container_of(work, struct generic_pm_domain, power_off_work);
 
 368
 369	mutex_lock(&genpd->lock);
 370	genpd_poweroff(genpd, true);
 371	mutex_unlock(&genpd->lock);
 372}
 373
 374/**
 375 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 376 * @dev: Device to suspend.
 377 *
 378 * Carry out a runtime suspend of a device under the assumption that its
 379 * pm_domain field points to the domain member of an object of type
 380 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 381 */
 382static int pm_genpd_runtime_suspend(struct device *dev)
 383{
 384	struct generic_pm_domain *genpd;
 385	bool (*stop_ok)(struct device *__dev);
 386	struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
 387	bool runtime_pm = pm_runtime_enabled(dev);
 388	ktime_t time_start;
 389	s64 elapsed_ns;
 390	int ret;
 391
 392	dev_dbg(dev, "%s()\n", __func__);
 393
 394	genpd = dev_to_genpd(dev);
 395	if (IS_ERR(genpd))
 396		return -EINVAL;
 397
 398	/*
 399	 * A runtime PM centric subsystem/driver may re-use the runtime PM
 400	 * callbacks for other purposes than runtime PM. In those scenarios
 401	 * runtime PM is disabled. Under these circumstances, we shall skip
 402	 * validating/measuring the PM QoS latency.
 403	 */
 404	stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
 405	if (runtime_pm && stop_ok && !stop_ok(dev))
 406		return -EBUSY;
 407
 408	/* Measure suspend latency. */
 
 409	if (runtime_pm)
 410		time_start = ktime_get();
 411
 412	ret = genpd_save_dev(genpd, dev);
 413	if (ret)
 414		return ret;
 415
 416	ret = genpd_stop_dev(genpd, dev);
 417	if (ret) {
 418		genpd_restore_dev(genpd, dev);
 419		return ret;
 420	}
 421
 422	/* Update suspend latency value if the measured time exceeds it. */
 423	if (runtime_pm) {
 424		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 425		if (elapsed_ns > td->suspend_latency_ns) {
 426			td->suspend_latency_ns = elapsed_ns;
 427			dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
 428				elapsed_ns);
 429			genpd->max_off_time_changed = true;
 430			td->constraint_changed = true;
 431		}
 432	}
 433
 434	/*
 435	 * If power.irq_safe is set, this routine will be run with interrupts
 436	 * off, so it can't use mutexes.
 437	 */
 438	if (dev->power.irq_safe)
 439		return 0;
 440
 441	mutex_lock(&genpd->lock);
 442	genpd_poweroff(genpd, false);
 443	mutex_unlock(&genpd->lock);
 444
 445	return 0;
 446}
 447
 448/**
 449 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
 450 * @dev: Device to resume.
 451 *
 452 * Carry out a runtime resume of a device under the assumption that its
 453 * pm_domain field points to the domain member of an object of type
 454 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 455 */
 456static int pm_genpd_runtime_resume(struct device *dev)
 457{
 458	struct generic_pm_domain *genpd;
 459	struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
 460	bool runtime_pm = pm_runtime_enabled(dev);
 461	ktime_t time_start;
 462	s64 elapsed_ns;
 463	int ret;
 464	bool timed = true;
 465
 466	dev_dbg(dev, "%s()\n", __func__);
 467
 468	genpd = dev_to_genpd(dev);
 469	if (IS_ERR(genpd))
 470		return -EINVAL;
 471
 472	/* If power.irq_safe, the PM domain is never powered off. */
 473	if (dev->power.irq_safe) {
 
 
 
 474		timed = false;
 475		goto out;
 476	}
 477
 478	mutex_lock(&genpd->lock);
 479	ret = genpd_poweron(genpd, 0);
 480	mutex_unlock(&genpd->lock);
 481
 482	if (ret)
 483		return ret;
 484
 485 out:
 486	/* Measure resume latency. */
 
 487	if (timed && runtime_pm)
 488		time_start = ktime_get();
 489
 490	ret = genpd_start_dev(genpd, dev);
 491	if (ret)
 492		goto err_poweroff;
 493
 494	ret = genpd_restore_dev(genpd, dev);
 495	if (ret)
 496		goto err_stop;
 497
 498	/* Update resume latency value if the measured time exceeds it. */
 499	if (timed && runtime_pm) {
 500		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 501		if (elapsed_ns > td->resume_latency_ns) {
 502			td->resume_latency_ns = elapsed_ns;
 503			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
 504				elapsed_ns);
 505			genpd->max_off_time_changed = true;
 506			td->constraint_changed = true;
 507		}
 508	}
 509
 510	return 0;
 511
 512err_stop:
 513	genpd_stop_dev(genpd, dev);
 514err_poweroff:
 515	if (!dev->power.irq_safe) {
 516		mutex_lock(&genpd->lock);
 517		genpd_poweroff(genpd, 0);
 518		mutex_unlock(&genpd->lock);
 
 519	}
 520
 521	return ret;
 522}
 523
 524static bool pd_ignore_unused;
 525static int __init pd_ignore_unused_setup(char *__unused)
 526{
 527	pd_ignore_unused = true;
 528	return 1;
 529}
 530__setup("pd_ignore_unused", pd_ignore_unused_setup);
 531
 532/**
 533 * genpd_poweroff_unused - Power off all PM domains with no devices in use.
 534 */
 535static int __init genpd_poweroff_unused(void)
 536{
 537	struct generic_pm_domain *genpd;
 538
 539	if (pd_ignore_unused) {
 540		pr_warn("genpd: Not disabling unused power domains\n");
 541		return 0;
 542	}
 543
 544	mutex_lock(&gpd_list_lock);
 545
 546	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
 547		genpd_queue_power_off_work(genpd);
 548
 549	mutex_unlock(&gpd_list_lock);
 550
 551	return 0;
 552}
 553late_initcall(genpd_poweroff_unused);
 554
 555#ifdef CONFIG_PM_SLEEP
 556
 557/**
 558 * pm_genpd_present - Check if the given PM domain has been initialized.
 559 * @genpd: PM domain to check.
 560 */
 561static bool pm_genpd_present(const struct generic_pm_domain *genpd)
 562{
 563	const struct generic_pm_domain *gpd;
 564
 565	if (IS_ERR_OR_NULL(genpd))
 566		return false;
 567
 568	list_for_each_entry(gpd, &gpd_list, gpd_list_node)
 569		if (gpd == genpd)
 570			return true;
 571
 572	return false;
 573}
 574
 575static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
 576				    struct device *dev)
 577{
 578	return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
 579}
 580
 581/**
 582 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
 583 * @genpd: PM domain to power off, if possible.
 584 * @timed: True if latency measurements are allowed.
 
 585 *
 586 * Check if the given PM domain can be powered off (during system suspend or
 587 * hibernation) and do that if so.  Also, in that case propagate to its masters.
 588 *
 589 * This function is only called in "noirq" and "syscore" stages of system power
 590 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 591 * executed sequentially, so it is guaranteed that it will never run twice in
 592 * parallel).
 593 */
 594static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
 595				   bool timed)
 596{
 597	struct gpd_link *link;
 598
 599	if (genpd->status == GPD_STATE_POWER_OFF)
 600		return;
 601
 602	if (genpd->suspended_count != genpd->device_count
 603	    || atomic_read(&genpd->sd_count) > 0)
 604		return;
 605
 606	/* Choose the deepest state when suspending */
 607	genpd->state_idx = genpd->state_count - 1;
 608	genpd_power_off(genpd, timed);
 
 609
 610	genpd->status = GPD_STATE_POWER_OFF;
 611
 612	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 613		genpd_sd_counter_dec(link->master);
 614		pm_genpd_sync_poweroff(link->master, timed);
 
 
 
 
 
 
 
 615	}
 616}
 617
 618/**
 619 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
 620 * @genpd: PM domain to power on.
 621 * @timed: True if latency measurements are allowed.
 
 622 *
 623 * This function is only called in "noirq" and "syscore" stages of system power
 624 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 625 * executed sequentially, so it is guaranteed that it will never run twice in
 626 * parallel).
 627 */
 628static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
 629				  bool timed)
 630{
 631	struct gpd_link *link;
 632
 633	if (genpd->status == GPD_STATE_ACTIVE)
 634		return;
 635
 636	list_for_each_entry(link, &genpd->slave_links, slave_node) {
 637		pm_genpd_sync_poweron(link->master, timed);
 638		genpd_sd_counter_inc(link->master);
 
 
 
 
 
 
 
 
 639	}
 640
 641	genpd_power_on(genpd, timed);
 642
 643	genpd->status = GPD_STATE_ACTIVE;
 644}
 645
 646/**
 647 * resume_needed - Check whether to resume a device before system suspend.
 648 * @dev: Device to check.
 649 * @genpd: PM domain the device belongs to.
 650 *
 651 * There are two cases in which a device that can wake up the system from sleep
 652 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
 653 * to wake up the system and it has to remain active for this purpose while the
 654 * system is in the sleep state and (2) if the device is not enabled to wake up
 655 * the system from sleep states and it generally doesn't generate wakeup signals
 656 * by itself (those signals are generated on its behalf by other parts of the
 657 * system).  In the latter case it may be necessary to reconfigure the device's
 658 * wakeup settings during system suspend, because it may have been set up to
 659 * signal remote wakeup from the system's working state as needed by runtime PM.
 660 * Return 'true' in either of the above cases.
 661 */
 662static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
 
 663{
 664	bool active_wakeup;
 665
 666	if (!device_can_wakeup(dev))
 667		return false;
 668
 669	active_wakeup = genpd_dev_active_wakeup(genpd, dev);
 670	return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
 671}
 672
 673/**
 674 * pm_genpd_prepare - Start power transition of a device in a PM domain.
 675 * @dev: Device to start the transition of.
 676 *
 677 * Start a power transition of a device (during a system-wide power transition)
 678 * under the assumption that its pm_domain field points to the domain member of
 679 * an object of type struct generic_pm_domain representing a PM domain
 680 * consisting of I/O devices.
 681 */
 682static int pm_genpd_prepare(struct device *dev)
 683{
 684	struct generic_pm_domain *genpd;
 685	int ret;
 686
 687	dev_dbg(dev, "%s()\n", __func__);
 688
 689	genpd = dev_to_genpd(dev);
 690	if (IS_ERR(genpd))
 691		return -EINVAL;
 692
 693	/*
 694	 * If a wakeup request is pending for the device, it should be woken up
 695	 * at this point and a system wakeup event should be reported if it's
 696	 * set up to wake up the system from sleep states.
 697	 */
 698	pm_runtime_get_noresume(dev);
 699	if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
 700		pm_wakeup_event(dev, 0);
 701
 702	if (pm_wakeup_pending()) {
 703		pm_runtime_put(dev);
 704		return -EBUSY;
 705	}
 706
 707	if (resume_needed(dev, genpd))
 708		pm_runtime_resume(dev);
 709
 710	mutex_lock(&genpd->lock);
 711
 712	if (genpd->prepared_count++ == 0) {
 713		genpd->suspended_count = 0;
 714		genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
 715	}
 716
 717	mutex_unlock(&genpd->lock);
 718
 719	if (genpd->suspend_power_off) {
 720		pm_runtime_put_noidle(dev);
 721		return 0;
 722	}
 723
 724	/*
 725	 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
 726	 * so genpd_poweron() will return immediately, but if the device
 727	 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
 728	 * to make it operational.
 729	 */
 730	pm_runtime_resume(dev);
 731	__pm_runtime_disable(dev, false);
 732
 733	ret = pm_generic_prepare(dev);
 734	if (ret) {
 735		mutex_lock(&genpd->lock);
 736
 737		if (--genpd->prepared_count == 0)
 738			genpd->suspend_power_off = false;
 739
 740		mutex_unlock(&genpd->lock);
 741		pm_runtime_enable(dev);
 742	}
 743
 744	pm_runtime_put(dev);
 745	return ret;
 746}
 747
 748/**
 749 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
 
 750 * @dev: Device to suspend.
 
 751 *
 752 * Suspend a device under the assumption that its pm_domain field points to the
 753 * domain member of an object of type struct generic_pm_domain representing
 754 * a PM domain consisting of I/O devices.
 755 */
 756static int pm_genpd_suspend(struct device *dev)
 757{
 758	struct generic_pm_domain *genpd;
 759
 760	dev_dbg(dev, "%s()\n", __func__);
 761
 762	genpd = dev_to_genpd(dev);
 763	if (IS_ERR(genpd))
 764		return -EINVAL;
 765
 766	return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
 767}
 
 
 
 
 768
 769/**
 770 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
 771 * @dev: Device to suspend.
 772 *
 773 * Carry out a late suspend of a device under the assumption that its
 774 * pm_domain field points to the domain member of an object of type
 775 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 776 */
 777static int pm_genpd_suspend_late(struct device *dev)
 778{
 779	struct generic_pm_domain *genpd;
 780
 781	dev_dbg(dev, "%s()\n", __func__);
 
 
 
 
 
 
 
 
 
 
 782
 783	genpd = dev_to_genpd(dev);
 784	if (IS_ERR(genpd))
 785		return -EINVAL;
 
 786
 787	return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
 788}
 789
 790/**
 791 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
 792 * @dev: Device to suspend.
 793 *
 794 * Stop the device and remove power from the domain if all devices in it have
 795 * been stopped.
 796 */
 797static int pm_genpd_suspend_noirq(struct device *dev)
 798{
 799	struct generic_pm_domain *genpd;
 800
 801	dev_dbg(dev, "%s()\n", __func__);
 802
 803	genpd = dev_to_genpd(dev);
 804	if (IS_ERR(genpd))
 805		return -EINVAL;
 806
 807	if (genpd->suspend_power_off
 808	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
 809		return 0;
 810
 811	genpd_stop_dev(genpd, dev);
 812
 813	/*
 814	 * Since all of the "noirq" callbacks are executed sequentially, it is
 815	 * guaranteed that this function will never run twice in parallel for
 816	 * the same PM domain, so it is not necessary to use locking here.
 817	 */
 818	genpd->suspended_count++;
 819	pm_genpd_sync_poweroff(genpd, true);
 820
 821	return 0;
 822}
 823
 824/**
 825 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
 826 * @dev: Device to resume.
 827 *
 828 * Restore power to the device's PM domain, if necessary, and start the device.
 829 */
 830static int pm_genpd_resume_noirq(struct device *dev)
 831{
 832	struct generic_pm_domain *genpd;
 
 833
 834	dev_dbg(dev, "%s()\n", __func__);
 835
 836	genpd = dev_to_genpd(dev);
 837	if (IS_ERR(genpd))
 838		return -EINVAL;
 839
 840	if (genpd->suspend_power_off
 841	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
 842		return 0;
 843
 844	/*
 845	 * Since all of the "noirq" callbacks are executed sequentially, it is
 846	 * guaranteed that this function will never run twice in parallel for
 847	 * the same PM domain, so it is not necessary to use locking here.
 848	 */
 849	pm_genpd_sync_poweron(genpd, true);
 850	genpd->suspended_count--;
 
 851
 852	return genpd_start_dev(genpd, dev);
 853}
 854
 855/**
 856 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
 857 * @dev: Device to resume.
 858 *
 859 * Carry out an early resume of a device under the assumption that its
 860 * pm_domain field points to the domain member of an object of type
 861 * struct generic_pm_domain representing a power domain consisting of I/O
 862 * devices.
 863 */
 864static int pm_genpd_resume_early(struct device *dev)
 865{
 866	struct generic_pm_domain *genpd;
 867
 868	dev_dbg(dev, "%s()\n", __func__);
 869
 870	genpd = dev_to_genpd(dev);
 871	if (IS_ERR(genpd))
 872		return -EINVAL;
 873
 874	return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
 875}
 876
 877/**
 878 * pm_genpd_resume - Resume of device in an I/O PM domain.
 879 * @dev: Device to resume.
 880 *
 881 * Resume a device under the assumption that its pm_domain field points to the
 882 * domain member of an object of type struct generic_pm_domain representing
 883 * a power domain consisting of I/O devices.
 884 */
 885static int pm_genpd_resume(struct device *dev)
 886{
 887	struct generic_pm_domain *genpd;
 888
 889	dev_dbg(dev, "%s()\n", __func__);
 890
 891	genpd = dev_to_genpd(dev);
 892	if (IS_ERR(genpd))
 893		return -EINVAL;
 894
 895	return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
 896}
 897
 898/**
 899 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
 900 * @dev: Device to freeze.
 901 *
 902 * Freeze a device under the assumption that its pm_domain field points to the
 903 * domain member of an object of type struct generic_pm_domain representing
 904 * a power domain consisting of I/O devices.
 905 */
 906static int pm_genpd_freeze(struct device *dev)
 907{
 908	struct generic_pm_domain *genpd;
 909
 910	dev_dbg(dev, "%s()\n", __func__);
 911
 912	genpd = dev_to_genpd(dev);
 913	if (IS_ERR(genpd))
 914		return -EINVAL;
 915
 916	return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
 917}
 918
 919/**
 920 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
 921 * @dev: Device to freeze.
 922 *
 923 * Carry out a late freeze of a device under the assumption that its
 924 * pm_domain field points to the domain member of an object of type
 925 * struct generic_pm_domain representing a power domain consisting of I/O
 926 * devices.
 927 */
 928static int pm_genpd_freeze_late(struct device *dev)
 929{
 930	struct generic_pm_domain *genpd;
 
 931
 932	dev_dbg(dev, "%s()\n", __func__);
 933
 934	genpd = dev_to_genpd(dev);
 935	if (IS_ERR(genpd))
 936		return -EINVAL;
 937
 938	return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
 939}
 
 940
 941/**
 942 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
 943 * @dev: Device to freeze.
 944 *
 945 * Carry out a late freeze of a device under the assumption that its
 946 * pm_domain field points to the domain member of an object of type
 947 * struct generic_pm_domain representing a power domain consisting of I/O
 948 * devices.
 949 */
 950static int pm_genpd_freeze_noirq(struct device *dev)
 951{
 952	struct generic_pm_domain *genpd;
 953
 954	dev_dbg(dev, "%s()\n", __func__);
 955
 956	genpd = dev_to_genpd(dev);
 957	if (IS_ERR(genpd))
 958		return -EINVAL;
 959
 960	return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
 961}
 962
 963/**
 964 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
 965 * @dev: Device to thaw.
 966 *
 967 * Start the device, unless power has been removed from the domain already
 968 * before the system transition.
 969 */
 970static int pm_genpd_thaw_noirq(struct device *dev)
 971{
 972	struct generic_pm_domain *genpd;
 
 973
 974	dev_dbg(dev, "%s()\n", __func__);
 975
 976	genpd = dev_to_genpd(dev);
 977	if (IS_ERR(genpd))
 978		return -EINVAL;
 979
 980	return genpd->suspend_power_off ?
 981		0 : genpd_start_dev(genpd, dev);
 982}
 983
 984/**
 985 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
 986 * @dev: Device to thaw.
 987 *
 988 * Carry out an early thaw of a device under the assumption that its
 989 * pm_domain field points to the domain member of an object of type
 990 * struct generic_pm_domain representing a power domain consisting of I/O
 991 * devices.
 992 */
 993static int pm_genpd_thaw_early(struct device *dev)
 994{
 995	struct generic_pm_domain *genpd;
 996
 997	dev_dbg(dev, "%s()\n", __func__);
 998
 999	genpd = dev_to_genpd(dev);
1000	if (IS_ERR(genpd))
1001		return -EINVAL;
1002
1003	return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
1004}
1005
1006/**
1007 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1008 * @dev: Device to thaw.
 
1009 *
1010 * Thaw a device under the assumption that its pm_domain field points to the
1011 * domain member of an object of type struct generic_pm_domain representing
1012 * a power domain consisting of I/O devices.
1013 */
1014static int pm_genpd_thaw(struct device *dev)
1015{
1016	struct generic_pm_domain *genpd;
1017
1018	dev_dbg(dev, "%s()\n", __func__);
1019
1020	genpd = dev_to_genpd(dev);
1021	if (IS_ERR(genpd))
1022		return -EINVAL;
1023
1024	return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
1025}
1026
1027/**
1028 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1029 * @dev: Device to resume.
1030 *
1031 * Make sure the domain will be in the same power state as before the
1032 * hibernation the system is resuming from and start the device if necessary.
1033 */
1034static int pm_genpd_restore_noirq(struct device *dev)
1035{
1036	struct generic_pm_domain *genpd;
 
1037
1038	dev_dbg(dev, "%s()\n", __func__);
1039
1040	genpd = dev_to_genpd(dev);
1041	if (IS_ERR(genpd))
1042		return -EINVAL;
1043
1044	/*
1045	 * Since all of the "noirq" callbacks are executed sequentially, it is
1046	 * guaranteed that this function will never run twice in parallel for
1047	 * the same PM domain, so it is not necessary to use locking here.
1048	 *
1049	 * At this point suspended_count == 0 means we are being run for the
1050	 * first time for the given domain in the present cycle.
1051	 */
1052	if (genpd->suspended_count++ == 0) {
 
1053		/*
1054		 * The boot kernel might put the domain into arbitrary state,
1055		 * so make it appear as powered off to pm_genpd_sync_poweron(),
1056		 * so that it tries to power it on in case it was really off.
1057		 */
1058		genpd->status = GPD_STATE_POWER_OFF;
1059		if (genpd->suspend_power_off) {
1060			/*
1061			 * If the domain was off before the hibernation, make
1062			 * sure it will be off going forward.
1063			 */
1064			genpd_power_off(genpd, true);
1065
1066			return 0;
1067		}
 
 
 
 
 
 
1068	}
1069
1070	if (genpd->suspend_power_off)
1071		return 0;
1072
1073	pm_genpd_sync_poweron(genpd, true);
1074
1075	return genpd_start_dev(genpd, dev);
1076}
1077
1078/**
1079 * pm_genpd_complete - Complete power transition of a device in a power domain.
1080 * @dev: Device to complete the transition of.
1081 *
1082 * Complete a power transition of a device (during a system-wide power
1083 * transition) under the assumption that its pm_domain field points to the
1084 * domain member of an object of type struct generic_pm_domain representing
1085 * a power domain consisting of I/O devices.
1086 */
1087static void pm_genpd_complete(struct device *dev)
1088{
1089	struct generic_pm_domain *genpd;
1090	bool run_complete;
1091
1092	dev_dbg(dev, "%s()\n", __func__);
1093
1094	genpd = dev_to_genpd(dev);
1095	if (IS_ERR(genpd))
1096		return;
1097
1098	mutex_lock(&genpd->lock);
 
 
1099
1100	run_complete = !genpd->suspend_power_off;
1101	if (--genpd->prepared_count == 0)
1102		genpd->suspend_power_off = false;
1103
1104	mutex_unlock(&genpd->lock);
1105
1106	if (run_complete) {
1107		pm_generic_complete(dev);
1108		pm_runtime_set_active(dev);
1109		pm_runtime_enable(dev);
1110		pm_request_idle(dev);
1111	}
1112}
1113
1114/**
1115 * genpd_syscore_switch - Switch power during system core suspend or resume.
1116 * @dev: Device that normally is marked as "always on" to switch power for.
1117 *
1118 * This routine may only be called during the system core (syscore) suspend or
1119 * resume phase for devices whose "always on" flags are set.
1120 */
1121static void genpd_syscore_switch(struct device *dev, bool suspend)
1122{
1123	struct generic_pm_domain *genpd;
1124
1125	genpd = dev_to_genpd(dev);
1126	if (!pm_genpd_present(genpd))
1127		return;
1128
1129	if (suspend) {
1130		genpd->suspended_count++;
1131		pm_genpd_sync_poweroff(genpd, false);
1132	} else {
1133		pm_genpd_sync_poweron(genpd, false);
1134		genpd->suspended_count--;
1135	}
1136}
1137
1138void pm_genpd_syscore_poweroff(struct device *dev)
1139{
1140	genpd_syscore_switch(dev, true);
1141}
1142EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
1143
1144void pm_genpd_syscore_poweron(struct device *dev)
1145{
1146	genpd_syscore_switch(dev, false);
1147}
1148EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1149
1150#else /* !CONFIG_PM_SLEEP */
1151
1152#define pm_genpd_prepare		NULL
1153#define pm_genpd_suspend		NULL
1154#define pm_genpd_suspend_late		NULL
1155#define pm_genpd_suspend_noirq		NULL
1156#define pm_genpd_resume_early		NULL
1157#define pm_genpd_resume_noirq		NULL
1158#define pm_genpd_resume			NULL
1159#define pm_genpd_freeze			NULL
1160#define pm_genpd_freeze_late		NULL
1161#define pm_genpd_freeze_noirq		NULL
1162#define pm_genpd_thaw_early		NULL
1163#define pm_genpd_thaw_noirq		NULL
1164#define pm_genpd_thaw			NULL
1165#define pm_genpd_restore_noirq		NULL
1166#define pm_genpd_complete		NULL
1167
1168#endif /* CONFIG_PM_SLEEP */
1169
1170static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1171					struct generic_pm_domain *genpd,
1172					struct gpd_timing_data *td)
1173{
1174	struct generic_pm_domain_data *gpd_data;
1175	int ret;
1176
1177	ret = dev_pm_get_subsys_data(dev);
1178	if (ret)
1179		return ERR_PTR(ret);
1180
1181	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1182	if (!gpd_data) {
1183		ret = -ENOMEM;
1184		goto err_put;
1185	}
1186
1187	if (td)
1188		gpd_data->td = *td;
1189
1190	gpd_data->base.dev = dev;
1191	gpd_data->td.constraint_changed = true;
1192	gpd_data->td.effective_constraint_ns = -1;
1193	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1194
1195	spin_lock_irq(&dev->power.lock);
1196
1197	if (dev->power.subsys_data->domain_data) {
1198		ret = -EINVAL;
1199		goto err_free;
1200	}
1201
1202	dev->power.subsys_data->domain_data = &gpd_data->base;
1203
1204	spin_unlock_irq(&dev->power.lock);
1205
1206	dev_pm_domain_set(dev, &genpd->domain);
1207
1208	return gpd_data;
1209
1210 err_free:
1211	spin_unlock_irq(&dev->power.lock);
1212	kfree(gpd_data);
1213 err_put:
1214	dev_pm_put_subsys_data(dev);
1215	return ERR_PTR(ret);
1216}
1217
1218static void genpd_free_dev_data(struct device *dev,
1219				struct generic_pm_domain_data *gpd_data)
1220{
1221	dev_pm_domain_set(dev, NULL);
1222
1223	spin_lock_irq(&dev->power.lock);
1224
1225	dev->power.subsys_data->domain_data = NULL;
1226
1227	spin_unlock_irq(&dev->power.lock);
1228
1229	kfree(gpd_data);
1230	dev_pm_put_subsys_data(dev);
1231}
1232
1233/**
1234 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1235 * @genpd: PM domain to add the device to.
1236 * @dev: Device to be added.
1237 * @td: Set of PM QoS timing parameters to attach to the device.
1238 */
1239int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1240			  struct gpd_timing_data *td)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1241{
1242	struct generic_pm_domain_data *gpd_data;
1243	int ret = 0;
1244
1245	dev_dbg(dev, "%s()\n", __func__);
1246
1247	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1248		return -EINVAL;
1249
1250	gpd_data = genpd_alloc_dev_data(dev, genpd, td);
1251	if (IS_ERR(gpd_data))
1252		return PTR_ERR(gpd_data);
1253
1254	mutex_lock(&genpd->lock);
1255
1256	if (genpd->prepared_count > 0) {
1257		ret = -EAGAIN;
1258		goto out;
1259	}
1260
1261	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1262	if (ret)
1263		goto out;
1264
 
 
 
 
 
1265	genpd->device_count++;
1266	genpd->max_off_time_changed = true;
1267
1268	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1269
 
1270 out:
1271	mutex_unlock(&genpd->lock);
1272
1273	if (ret)
1274		genpd_free_dev_data(dev, gpd_data);
1275	else
1276		dev_pm_qos_add_notifier(dev, &gpd_data->nb);
 
1277
1278	return ret;
1279}
1280EXPORT_SYMBOL_GPL(__pm_genpd_add_device);
1281
1282/**
1283 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1284 * @genpd: PM domain to remove the device from.
1285 * @dev: Device to be removed.
1286 */
1287int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1288			   struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
1289{
1290	struct generic_pm_domain_data *gpd_data;
1291	struct pm_domain_data *pdd;
1292	int ret = 0;
1293
1294	dev_dbg(dev, "%s()\n", __func__);
1295
1296	if (!genpd || genpd != pm_genpd_lookup_dev(dev))
1297		return -EINVAL;
1298
1299	/* The above validation also means we have existing domain_data. */
1300	pdd = dev->power.subsys_data->domain_data;
1301	gpd_data = to_gpd_data(pdd);
1302	dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
 
1303
1304	mutex_lock(&genpd->lock);
1305
1306	if (genpd->prepared_count > 0) {
1307		ret = -EAGAIN;
1308		goto out;
1309	}
1310
1311	genpd->device_count--;
1312	genpd->max_off_time_changed = true;
1313
1314	if (genpd->detach_dev)
1315		genpd->detach_dev(genpd, dev);
1316
1317	list_del_init(&pdd->list_node);
1318
1319	mutex_unlock(&genpd->lock);
 
 
 
1320
1321	genpd_free_dev_data(dev, gpd_data);
1322
1323	return 0;
1324
1325 out:
1326	mutex_unlock(&genpd->lock);
1327	dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1328
1329	return ret;
1330}
1331EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1332
1333/**
1334 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1335 * @genpd: Master PM domain to add the subdomain to.
1336 * @subdomain: Subdomain to be added.
1337 */
1338int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1339			   struct generic_pm_domain *subdomain)
 
 
 
 
 
 
 
 
 
 
 
1340{
1341	struct gpd_link *link, *itr;
1342	int ret = 0;
1343
1344	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1345	    || genpd == subdomain)
1346		return -EINVAL;
1347
 
 
 
 
 
 
 
 
 
 
 
1348	link = kzalloc(sizeof(*link), GFP_KERNEL);
1349	if (!link)
1350		return -ENOMEM;
1351
1352	mutex_lock(&subdomain->lock);
1353	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
1354
1355	if (genpd->status == GPD_STATE_POWER_OFF
1356	    &&  subdomain->status != GPD_STATE_POWER_OFF) {
1357		ret = -EINVAL;
1358		goto out;
1359	}
1360
1361	list_for_each_entry(itr, &genpd->master_links, master_node) {
1362		if (itr->slave == subdomain && itr->master == genpd) {
1363			ret = -EINVAL;
1364			goto out;
1365		}
1366	}
1367
1368	link->master = genpd;
1369	list_add_tail(&link->master_node, &genpd->master_links);
1370	link->slave = subdomain;
1371	list_add_tail(&link->slave_node, &subdomain->slave_links);
1372	if (subdomain->status != GPD_STATE_POWER_OFF)
1373		genpd_sd_counter_inc(genpd);
1374
1375 out:
1376	mutex_unlock(&genpd->lock);
1377	mutex_unlock(&subdomain->lock);
1378	if (ret)
1379		kfree(link);
1380	return ret;
1381}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1382EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1383
1384/**
1385 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1386 * @genpd: Master PM domain to remove the subdomain from.
1387 * @subdomain: Subdomain to be removed.
1388 */
1389int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1390			      struct generic_pm_domain *subdomain)
1391{
1392	struct gpd_link *link;
1393	int ret = -EINVAL;
1394
1395	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1396		return -EINVAL;
1397
1398	mutex_lock(&subdomain->lock);
1399	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
1400
1401	if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
1402		pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
1403			subdomain->name);
1404		ret = -EBUSY;
1405		goto out;
1406	}
1407
1408	list_for_each_entry(link, &genpd->master_links, master_node) {
1409		if (link->slave != subdomain)
1410			continue;
1411
1412		list_del(&link->master_node);
1413		list_del(&link->slave_node);
1414		kfree(link);
1415		if (subdomain->status != GPD_STATE_POWER_OFF)
1416			genpd_sd_counter_dec(genpd);
1417
1418		ret = 0;
1419		break;
1420	}
1421
1422out:
1423	mutex_unlock(&genpd->lock);
1424	mutex_unlock(&subdomain->lock);
1425
1426	return ret;
1427}
1428EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1429
1430/* Default device callbacks for generic PM domains. */
 
 
 
 
1431
1432/**
1433 * pm_genpd_default_save_state - Default "save device state" for PM domains.
1434 * @dev: Device to handle.
1435 */
1436static int pm_genpd_default_save_state(struct device *dev)
1437{
1438	int (*cb)(struct device *__dev);
1439
1440	if (dev->type && dev->type->pm)
1441		cb = dev->type->pm->runtime_suspend;
1442	else if (dev->class && dev->class->pm)
1443		cb = dev->class->pm->runtime_suspend;
1444	else if (dev->bus && dev->bus->pm)
1445		cb = dev->bus->pm->runtime_suspend;
1446	else
1447		cb = NULL;
1448
1449	if (!cb && dev->driver && dev->driver->pm)
1450		cb = dev->driver->pm->runtime_suspend;
 
1451
1452	return cb ? cb(dev) : 0;
1453}
1454
1455/**
1456 * pm_genpd_default_restore_state - Default PM domains "restore device state".
1457 * @dev: Device to handle.
1458 */
1459static int pm_genpd_default_restore_state(struct device *dev)
1460{
1461	int (*cb)(struct device *__dev);
1462
1463	if (dev->type && dev->type->pm)
1464		cb = dev->type->pm->runtime_resume;
1465	else if (dev->class && dev->class->pm)
1466		cb = dev->class->pm->runtime_resume;
1467	else if (dev->bus && dev->bus->pm)
1468		cb = dev->bus->pm->runtime_resume;
1469	else
1470		cb = NULL;
1471
1472	if (!cb && dev->driver && dev->driver->pm)
1473		cb = dev->driver->pm->runtime_resume;
1474
1475	return cb ? cb(dev) : 0;
1476}
1477
1478/**
1479 * pm_genpd_init - Initialize a generic I/O PM domain object.
1480 * @genpd: PM domain object to initialize.
1481 * @gov: PM domain governor to associate with the domain (may be NULL).
1482 * @is_off: Initial value of the domain's power_is_off field.
 
 
1483 */
1484void pm_genpd_init(struct generic_pm_domain *genpd,
1485		   struct dev_power_governor *gov, bool is_off)
1486{
 
 
1487	if (IS_ERR_OR_NULL(genpd))
1488		return;
1489
1490	INIT_LIST_HEAD(&genpd->master_links);
1491	INIT_LIST_HEAD(&genpd->slave_links);
1492	INIT_LIST_HEAD(&genpd->dev_list);
1493	mutex_init(&genpd->lock);
1494	genpd->gov = gov;
1495	INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
1496	atomic_set(&genpd->sd_count, 0);
1497	genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
1498	genpd->device_count = 0;
1499	genpd->max_off_time_ns = -1;
1500	genpd->max_off_time_changed = true;
1501	genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
1502	genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
1503	genpd->domain.ops.prepare = pm_genpd_prepare;
1504	genpd->domain.ops.suspend = pm_genpd_suspend;
1505	genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
1506	genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
1507	genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
1508	genpd->domain.ops.resume_early = pm_genpd_resume_early;
1509	genpd->domain.ops.resume = pm_genpd_resume;
1510	genpd->domain.ops.freeze = pm_genpd_freeze;
1511	genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
1512	genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
1513	genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
1514	genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
1515	genpd->domain.ops.thaw = pm_genpd_thaw;
1516	genpd->domain.ops.poweroff = pm_genpd_suspend;
1517	genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
1518	genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
1519	genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
1520	genpd->domain.ops.restore_early = pm_genpd_resume_early;
1521	genpd->domain.ops.restore = pm_genpd_resume;
1522	genpd->domain.ops.complete = pm_genpd_complete;
1523	genpd->dev_ops.save_state = pm_genpd_default_save_state;
1524	genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
1525
1526	if (genpd->flags & GENPD_FLAG_PM_CLK) {
1527		genpd->dev_ops.stop = pm_clk_suspend;
1528		genpd->dev_ops.start = pm_clk_resume;
1529	}
1530
1531	if (genpd->state_idx >= GENPD_MAX_NUM_STATES) {
1532		pr_warn("Initial state index out of bounds.\n");
1533		genpd->state_idx = GENPD_MAX_NUM_STATES - 1;
1534	}
 
 
 
 
1535
1536	if (genpd->state_count > GENPD_MAX_NUM_STATES) {
1537		pr_warn("Limiting states to  %d\n", GENPD_MAX_NUM_STATES);
1538		genpd->state_count = GENPD_MAX_NUM_STATES;
 
 
 
 
 
 
 
1539	}
1540
1541	/* Use only one "off" state if there were no states declared */
1542	if (genpd->state_count == 0)
1543		genpd->state_count = 1;
1544
1545	mutex_lock(&gpd_list_lock);
1546	list_add(&genpd->gpd_list_node, &gpd_list);
1547	mutex_unlock(&gpd_list_lock);
 
 
1548}
1549EXPORT_SYMBOL_GPL(pm_genpd_init);
1550
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1551#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
 
1552/*
1553 * Device Tree based PM domain providers.
1554 *
1555 * The code below implements generic device tree based PM domain providers that
1556 * bind device tree nodes with generic PM domains registered in the system.
1557 *
1558 * Any driver that registers generic PM domains and needs to support binding of
1559 * devices to these domains is supposed to register a PM domain provider, which
1560 * maps a PM domain specifier retrieved from the device tree to a PM domain.
1561 *
1562 * Two simple mapping functions have been provided for convenience:
1563 *  - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
1564 *  - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
1565 *    index.
1566 */
1567
1568/**
1569 * struct of_genpd_provider - PM domain provider registration structure
1570 * @link: Entry in global list of PM domain providers
1571 * @node: Pointer to device tree node of PM domain provider
1572 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
1573 *         into a PM domain.
1574 * @data: context pointer to be passed into @xlate callback
1575 */
1576struct of_genpd_provider {
1577	struct list_head link;
1578	struct device_node *node;
1579	genpd_xlate_t xlate;
1580	void *data;
1581};
1582
1583/* List of registered PM domain providers. */
1584static LIST_HEAD(of_genpd_providers);
1585/* Mutex to protect the list above. */
1586static DEFINE_MUTEX(of_genpd_mutex);
1587
1588/**
1589 * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
1590 * @genpdspec: OF phandle args to map into a PM domain
1591 * @data: xlate function private data - pointer to struct generic_pm_domain
1592 *
1593 * This is a generic xlate function that can be used to model PM domains that
1594 * have their own device tree nodes. The private data of xlate function needs
1595 * to be a valid pointer to struct generic_pm_domain.
1596 */
1597struct generic_pm_domain *__of_genpd_xlate_simple(
1598					struct of_phandle_args *genpdspec,
1599					void *data)
1600{
1601	if (genpdspec->args_count != 0)
1602		return ERR_PTR(-EINVAL);
1603	return data;
1604}
1605EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
1606
1607/**
1608 * __of_genpd_xlate_onecell() - Xlate function using a single index.
1609 * @genpdspec: OF phandle args to map into a PM domain
1610 * @data: xlate function private data - pointer to struct genpd_onecell_data
1611 *
1612 * This is a generic xlate function that can be used to model simple PM domain
1613 * controllers that have one device tree node and provide multiple PM domains.
1614 * A single cell is used as an index into an array of PM domains specified in
1615 * the genpd_onecell_data struct when registering the provider.
1616 */
1617struct generic_pm_domain *__of_genpd_xlate_onecell(
1618					struct of_phandle_args *genpdspec,
1619					void *data)
1620{
1621	struct genpd_onecell_data *genpd_data = data;
1622	unsigned int idx = genpdspec->args[0];
1623
1624	if (genpdspec->args_count != 1)
1625		return ERR_PTR(-EINVAL);
1626
1627	if (idx >= genpd_data->num_domains) {
1628		pr_err("%s: invalid domain index %u\n", __func__, idx);
1629		return ERR_PTR(-EINVAL);
1630	}
1631
1632	if (!genpd_data->domains[idx])
1633		return ERR_PTR(-ENOENT);
1634
1635	return genpd_data->domains[idx];
1636}
1637EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
1638
1639/**
1640 * __of_genpd_add_provider() - Register a PM domain provider for a node
1641 * @np: Device node pointer associated with the PM domain provider.
1642 * @xlate: Callback for decoding PM domain from phandle arguments.
1643 * @data: Context pointer for @xlate callback.
1644 */
1645int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
1646			void *data)
1647{
1648	struct of_genpd_provider *cp;
1649
1650	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
1651	if (!cp)
1652		return -ENOMEM;
1653
1654	cp->node = of_node_get(np);
1655	cp->data = data;
1656	cp->xlate = xlate;
1657
1658	mutex_lock(&of_genpd_mutex);
1659	list_add(&cp->link, &of_genpd_providers);
1660	mutex_unlock(&of_genpd_mutex);
1661	pr_debug("Added domain provider from %s\n", np->full_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1662
1663	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1664}
1665EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
1666
1667/**
1668 * of_genpd_del_provider() - Remove a previously registered PM domain provider
1669 * @np: Device node pointer associated with the PM domain provider
1670 */
1671void of_genpd_del_provider(struct device_node *np)
1672{
1673	struct of_genpd_provider *cp;
 
1674
 
1675	mutex_lock(&of_genpd_mutex);
1676	list_for_each_entry(cp, &of_genpd_providers, link) {
1677		if (cp->node == np) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1678			list_del(&cp->link);
1679			of_node_put(cp->node);
1680			kfree(cp);
1681			break;
1682		}
1683	}
1684	mutex_unlock(&of_genpd_mutex);
 
1685}
1686EXPORT_SYMBOL_GPL(of_genpd_del_provider);
1687
1688/**
1689 * of_genpd_get_from_provider() - Look-up PM domain
1690 * @genpdspec: OF phandle args to use for look-up
1691 *
1692 * Looks for a PM domain provider under the node specified by @genpdspec and if
1693 * found, uses xlate function of the provider to map phandle args to a PM
1694 * domain.
1695 *
1696 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
1697 * on failure.
1698 */
1699struct generic_pm_domain *of_genpd_get_from_provider(
1700					struct of_phandle_args *genpdspec)
1701{
1702	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
1703	struct of_genpd_provider *provider;
1704
1705	if (!genpdspec)
1706		return ERR_PTR(-EINVAL);
1707
1708	mutex_lock(&of_genpd_mutex);
1709
1710	/* Check if we have such a provider in our array */
1711	list_for_each_entry(provider, &of_genpd_providers, link) {
1712		if (provider->node == genpdspec->np)
1713			genpd = provider->xlate(genpdspec, provider->data);
1714		if (!IS_ERR(genpd))
1715			break;
1716	}
1717
1718	mutex_unlock(&of_genpd_mutex);
1719
1720	return genpd;
1721}
1722EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1723
1724/**
1725 * genpd_dev_pm_detach - Detach a device from its PM domain.
1726 * @dev: Device to detach.
1727 * @power_off: Currently not used
1728 *
1729 * Try to locate a corresponding generic PM domain, which the device was
1730 * attached to previously. If such is found, the device is detached from it.
1731 */
1732static void genpd_dev_pm_detach(struct device *dev, bool power_off)
1733{
1734	struct generic_pm_domain *pd;
1735	unsigned int i;
1736	int ret = 0;
1737
1738	pd = pm_genpd_lookup_dev(dev);
1739	if (!pd)
1740		return;
1741
1742	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
1743
1744	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1745		ret = pm_genpd_remove_device(pd, dev);
1746		if (ret != -EAGAIN)
1747			break;
1748
1749		mdelay(i);
1750		cond_resched();
1751	}
1752
1753	if (ret < 0) {
1754		dev_err(dev, "failed to remove from PM domain %s: %d",
1755			pd->name, ret);
1756		return;
1757	}
1758
1759	/* Check if PM domain can be powered off after removing this device. */
1760	genpd_queue_power_off_work(pd);
 
 
 
 
1761}
1762
1763static void genpd_dev_pm_sync(struct device *dev)
1764{
1765	struct generic_pm_domain *pd;
1766
1767	pd = dev_to_genpd(dev);
1768	if (IS_ERR(pd))
1769		return;
1770
1771	genpd_queue_power_off_work(pd);
1772}
1773
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1774/**
1775 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
1776 * @dev: Device to attach.
1777 *
1778 * Parse device's OF node to find a PM domain specifier. If such is found,
1779 * attaches the device to retrieved pm_domain ops.
1780 *
1781 * Both generic and legacy Samsung-specific DT bindings are supported to keep
1782 * backwards compatibility with existing DTBs.
1783 *
1784 * Returns 0 on successfully attached PM domain or negative error code. Note
1785 * that if a power-domain exists for the device, but it cannot be found or
1786 * turned on, then return -EPROBE_DEFER to ensure that the device is not
1787 * probed and to re-try again later.
1788 */
1789int genpd_dev_pm_attach(struct device *dev)
1790{
1791	struct of_phandle_args pd_args;
1792	struct generic_pm_domain *pd;
1793	unsigned int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1794	int ret;
1795
1796	if (!dev->of_node)
1797		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1798
1799	if (dev->pm_domain)
1800		return -EEXIST;
1801
1802	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
1803					"#power-domain-cells", 0, &pd_args);
1804	if (ret < 0) {
1805		if (ret != -ENOENT)
1806			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1807
1808		/*
1809		 * Try legacy Samsung-specific bindings
1810		 * (for backwards compatibility of DT ABI)
1811		 */
1812		pd_args.args_count = 0;
1813		pd_args.np = of_parse_phandle(dev->of_node,
1814						"samsung,power-domain", 0);
1815		if (!pd_args.np)
1816			return -ENOENT;
1817	}
1818
1819	pd = of_genpd_get_from_provider(&pd_args);
1820	of_node_put(pd_args.np);
1821	if (IS_ERR(pd)) {
1822		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
1823			__func__, PTR_ERR(pd));
1824		return -EPROBE_DEFER;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1825	}
1826
1827	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1828
1829	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1830		ret = pm_genpd_add_device(pd, dev);
1831		if (ret != -EAGAIN)
1832			break;
1833
1834		mdelay(i);
1835		cond_resched();
 
 
1836	}
1837
1838	if (ret < 0) {
1839		dev_err(dev, "failed to add to PM domain %s: %d",
1840			pd->name, ret);
1841		goto out;
 
 
 
 
1842	}
1843
1844	dev->pm_domain->detach = genpd_dev_pm_detach;
1845	dev->pm_domain->sync = genpd_dev_pm_sync;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1846
1847	mutex_lock(&pd->lock);
1848	ret = genpd_poweron(pd, 0);
1849	mutex_unlock(&pd->lock);
1850out:
1851	return ret ? -EPROBE_DEFER : 0;
1852}
1853EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
 
1854#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
1855
1856
1857/***        debugfs support        ***/
1858
1859#ifdef CONFIG_PM_ADVANCED_DEBUG
1860#include <linux/pm.h>
1861#include <linux/device.h>
1862#include <linux/debugfs.h>
1863#include <linux/seq_file.h>
1864#include <linux/init.h>
1865#include <linux/kobject.h>
1866static struct dentry *pm_genpd_debugfs_dir;
1867
1868/*
1869 * TODO: This function is a slightly modified version of rtpm_status_show
1870 * from sysfs.c, so generalize it.
1871 */
1872static void rtpm_status_str(struct seq_file *s, struct device *dev)
1873{
1874	static const char * const status_lookup[] = {
1875		[RPM_ACTIVE] = "active",
1876		[RPM_RESUMING] = "resuming",
1877		[RPM_SUSPENDED] = "suspended",
1878		[RPM_SUSPENDING] = "suspending"
1879	};
1880	const char *p = "";
1881
1882	if (dev->power.runtime_error)
1883		p = "error";
1884	else if (dev->power.disable_depth)
1885		p = "unsupported";
1886	else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
1887		p = status_lookup[dev->power.runtime_status];
1888	else
1889		WARN_ON(1);
1890
1891	seq_puts(s, p);
1892}
1893
1894static int pm_genpd_summary_one(struct seq_file *s,
1895				struct generic_pm_domain *genpd)
1896{
1897	static const char * const status_lookup[] = {
1898		[GPD_STATE_ACTIVE] = "on",
1899		[GPD_STATE_POWER_OFF] = "off"
1900	};
1901	struct pm_domain_data *pm_data;
1902	const char *kobj_path;
1903	struct gpd_link *link;
1904	char state[16];
1905	int ret;
1906
1907	ret = mutex_lock_interruptible(&genpd->lock);
1908	if (ret)
1909		return -ERESTARTSYS;
1910
1911	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
1912		goto exit;
1913	if (genpd->status == GPD_STATE_POWER_OFF)
1914		snprintf(state, sizeof(state), "%s-%u",
1915			 status_lookup[genpd->status], genpd->state_idx);
1916	else
1917		snprintf(state, sizeof(state), "%s",
1918			 status_lookup[genpd->status]);
1919	seq_printf(s, "%-30s  %-15s ", genpd->name, state);
1920
1921	/*
1922	 * Modifications on the list require holding locks on both
1923	 * master and slave, so we are safe.
1924	 * Also genpd->name is immutable.
1925	 */
1926	list_for_each_entry(link, &genpd->master_links, master_node) {
1927		seq_printf(s, "%s", link->slave->name);
1928		if (!list_is_last(&link->master_node, &genpd->master_links))
1929			seq_puts(s, ", ");
1930	}
1931
1932	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
1933		kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
 
 
1934		if (kobj_path == NULL)
1935			continue;
1936
1937		seq_printf(s, "\n    %-50s  ", kobj_path);
1938		rtpm_status_str(s, pm_data->dev);
1939		kfree(kobj_path);
1940	}
1941
1942	seq_puts(s, "\n");
1943exit:
1944	mutex_unlock(&genpd->lock);
1945
1946	return 0;
1947}
1948
1949static int pm_genpd_summary_show(struct seq_file *s, void *data)
1950{
1951	struct generic_pm_domain *genpd;
1952	int ret = 0;
1953
1954	seq_puts(s, "domain                          status          slaves\n");
1955	seq_puts(s, "    /device                                             runtime status\n");
1956	seq_puts(s, "----------------------------------------------------------------------\n");
1957
1958	ret = mutex_lock_interruptible(&gpd_list_lock);
1959	if (ret)
1960		return -ERESTARTSYS;
1961
1962	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
1963		ret = pm_genpd_summary_one(s, genpd);
1964		if (ret)
1965			break;
1966	}
1967	mutex_unlock(&gpd_list_lock);
1968
1969	return ret;
1970}
1971
1972static int pm_genpd_summary_open(struct inode *inode, struct file *file)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1973{
1974	return single_open(file, pm_genpd_summary_show, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1975}
1976
1977static const struct file_operations pm_genpd_summary_fops = {
1978	.open = pm_genpd_summary_open,
1979	.read = seq_read,
1980	.llseek = seq_lseek,
1981	.release = single_release,
1982};
1983
1984static int __init pm_genpd_debug_init(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1985{
1986	struct dentry *d;
 
 
 
1987
1988	pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
 
1989
1990	if (!pm_genpd_debugfs_dir)
1991		return -ENOMEM;
1992
1993	d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
1994			pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
1995	if (!d)
1996		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
1997
1998	return 0;
1999}
2000late_initcall(pm_genpd_debug_init);
2001
2002static void __exit pm_genpd_debug_exit(void)
2003{
2004	debugfs_remove_recursive(pm_genpd_debugfs_dir);
2005}
2006__exitcall(pm_genpd_debug_exit);
2007#endif /* CONFIG_PM_ADVANCED_DEBUG */