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v6.13.7
   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/idr.h>
  11#include <linux/kernel.h>
  12#include <linux/io.h>
  13#include <linux/platform_device.h>
  14#include <linux/pm_opp.h>
  15#include <linux/pm_runtime.h>
  16#include <linux/pm_domain.h>
  17#include <linux/pm_qos.h>
  18#include <linux/pm_clock.h>
  19#include <linux/slab.h>
  20#include <linux/err.h>
  21#include <linux/sched.h>
  22#include <linux/suspend.h>
  23#include <linux/export.h>
  24#include <linux/cpu.h>
  25#include <linux/debugfs.h>
  26
  27/* Provides a unique ID for each genpd device */
  28static DEFINE_IDA(genpd_ida);
  29
  30#define GENPD_RETRY_MAX_MS	250		/* Approximate */
  31
  32#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)		\
  33({								\
  34	type (*__routine)(struct device *__d); 			\
  35	type __ret = (type)0;					\
  36								\
  37	__routine = genpd->dev_ops.callback; 			\
  38	if (__routine) {					\
  39		__ret = __routine(dev); 			\
  40	}							\
  41	__ret;							\
  42})
  43
  44static LIST_HEAD(gpd_list);
  45static DEFINE_MUTEX(gpd_list_lock);
  46
  47struct genpd_lock_ops {
  48	void (*lock)(struct generic_pm_domain *genpd);
  49	void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
  50	int (*lock_interruptible)(struct generic_pm_domain *genpd);
  51	void (*unlock)(struct generic_pm_domain *genpd);
  52};
  53
  54static void genpd_lock_mtx(struct generic_pm_domain *genpd)
  55{
  56	mutex_lock(&genpd->mlock);
  57}
  58
  59static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
  60					int depth)
  61{
  62	mutex_lock_nested(&genpd->mlock, depth);
  63}
  64
  65static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
  66{
  67	return mutex_lock_interruptible(&genpd->mlock);
  68}
  69
  70static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
  71{
  72	return mutex_unlock(&genpd->mlock);
  73}
  74
  75static const struct genpd_lock_ops genpd_mtx_ops = {
  76	.lock = genpd_lock_mtx,
  77	.lock_nested = genpd_lock_nested_mtx,
  78	.lock_interruptible = genpd_lock_interruptible_mtx,
  79	.unlock = genpd_unlock_mtx,
  80};
  81
  82static void genpd_lock_spin(struct generic_pm_domain *genpd)
  83	__acquires(&genpd->slock)
  84{
  85	unsigned long flags;
  86
  87	spin_lock_irqsave(&genpd->slock, flags);
  88	genpd->lock_flags = flags;
  89}
  90
  91static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
  92					int depth)
  93	__acquires(&genpd->slock)
  94{
  95	unsigned long flags;
  96
  97	spin_lock_irqsave_nested(&genpd->slock, flags, depth);
  98	genpd->lock_flags = flags;
  99}
 100
 101static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
 102	__acquires(&genpd->slock)
 103{
 104	unsigned long flags;
 105
 106	spin_lock_irqsave(&genpd->slock, flags);
 107	genpd->lock_flags = flags;
 108	return 0;
 109}
 110
 111static void genpd_unlock_spin(struct generic_pm_domain *genpd)
 112	__releases(&genpd->slock)
 113{
 114	spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
 115}
 116
 117static const struct genpd_lock_ops genpd_spin_ops = {
 118	.lock = genpd_lock_spin,
 119	.lock_nested = genpd_lock_nested_spin,
 120	.lock_interruptible = genpd_lock_interruptible_spin,
 121	.unlock = genpd_unlock_spin,
 122};
 123
 124static void genpd_lock_raw_spin(struct generic_pm_domain *genpd)
 125	__acquires(&genpd->raw_slock)
 126{
 127	unsigned long flags;
 128
 129	raw_spin_lock_irqsave(&genpd->raw_slock, flags);
 130	genpd->raw_lock_flags = flags;
 131}
 132
 133static void genpd_lock_nested_raw_spin(struct generic_pm_domain *genpd,
 134					int depth)
 135	__acquires(&genpd->raw_slock)
 136{
 137	unsigned long flags;
 138
 139	raw_spin_lock_irqsave_nested(&genpd->raw_slock, flags, depth);
 140	genpd->raw_lock_flags = flags;
 141}
 142
 143static int genpd_lock_interruptible_raw_spin(struct generic_pm_domain *genpd)
 144	__acquires(&genpd->raw_slock)
 145{
 146	unsigned long flags;
 147
 148	raw_spin_lock_irqsave(&genpd->raw_slock, flags);
 149	genpd->raw_lock_flags = flags;
 150	return 0;
 151}
 152
 153static void genpd_unlock_raw_spin(struct generic_pm_domain *genpd)
 154	__releases(&genpd->raw_slock)
 155{
 156	raw_spin_unlock_irqrestore(&genpd->raw_slock, genpd->raw_lock_flags);
 157}
 158
 159static const struct genpd_lock_ops genpd_raw_spin_ops = {
 160	.lock = genpd_lock_raw_spin,
 161	.lock_nested = genpd_lock_nested_raw_spin,
 162	.lock_interruptible = genpd_lock_interruptible_raw_spin,
 163	.unlock = genpd_unlock_raw_spin,
 164};
 165
 166#define genpd_lock(p)			p->lock_ops->lock(p)
 167#define genpd_lock_nested(p, d)		p->lock_ops->lock_nested(p, d)
 168#define genpd_lock_interruptible(p)	p->lock_ops->lock_interruptible(p)
 169#define genpd_unlock(p)			p->lock_ops->unlock(p)
 170
 171#define genpd_status_on(genpd)		(genpd->status == GENPD_STATE_ON)
 172#define genpd_is_irq_safe(genpd)	(genpd->flags & GENPD_FLAG_IRQ_SAFE)
 173#define genpd_is_always_on(genpd)	(genpd->flags & GENPD_FLAG_ALWAYS_ON)
 174#define genpd_is_active_wakeup(genpd)	(genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
 175#define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
 176#define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
 177#define genpd_is_opp_table_fw(genpd)	(genpd->flags & GENPD_FLAG_OPP_TABLE_FW)
 178#define genpd_is_dev_name_fw(genpd)	(genpd->flags & GENPD_FLAG_DEV_NAME_FW)
 179
 180static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
 181		const struct generic_pm_domain *genpd)
 182{
 183	bool ret;
 184
 185	ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
 186
 187	/*
 188	 * Warn once if an IRQ safe device is attached to a domain, which
 189	 * callbacks are allowed to sleep. This indicates a suboptimal
 190	 * configuration for PM, but it doesn't matter for an always on domain.
 191	 */
 192	if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
 193		return ret;
 194
 195	if (ret)
 196		dev_warn_once(dev, "PM domain %s will not be powered off\n",
 197			      dev_name(&genpd->dev));
 198
 199	return ret;
 200}
 201
 202static int genpd_runtime_suspend(struct device *dev);
 203
 204/*
 205 * Get the generic PM domain for a particular struct device.
 206 * This validates the struct device pointer, the PM domain pointer,
 207 * and checks that the PM domain pointer is a real generic PM domain.
 208 * Any failure results in NULL being returned.
 209 */
 210static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
 211{
 212	if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
 213		return NULL;
 214
 215	/* A genpd's always have its ->runtime_suspend() callback assigned. */
 216	if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
 217		return pd_to_genpd(dev->pm_domain);
 218
 219	return NULL;
 220}
 221
 222/*
 223 * This should only be used where we are certain that the pm_domain
 224 * attached to the device is a genpd domain.
 225 */
 226static struct generic_pm_domain *dev_to_genpd(struct device *dev)
 227{
 228	if (IS_ERR_OR_NULL(dev->pm_domain))
 229		return ERR_PTR(-EINVAL);
 230
 231	return pd_to_genpd(dev->pm_domain);
 232}
 233
 234struct device *dev_to_genpd_dev(struct device *dev)
 235{
 236	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 237
 238	if (IS_ERR(genpd))
 239		return ERR_CAST(genpd);
 240
 241	return &genpd->dev;
 242}
 243
 244static int genpd_stop_dev(const struct generic_pm_domain *genpd,
 245			  struct device *dev)
 246{
 247	return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
 248}
 249
 250static int genpd_start_dev(const struct generic_pm_domain *genpd,
 251			   struct device *dev)
 252{
 253	return GENPD_DEV_CALLBACK(genpd, int, start, dev);
 254}
 255
 256static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
 257{
 258	bool ret = false;
 259
 260	if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
 261		ret = !!atomic_dec_and_test(&genpd->sd_count);
 262
 263	return ret;
 264}
 265
 266static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 267{
 268	atomic_inc(&genpd->sd_count);
 269	smp_mb__after_atomic();
 270}
 271
 272#ifdef CONFIG_DEBUG_FS
 273static struct dentry *genpd_debugfs_dir;
 274
 275static void genpd_debug_add(struct generic_pm_domain *genpd);
 276
 277static void genpd_debug_remove(struct generic_pm_domain *genpd)
 278{
 279	if (!genpd_debugfs_dir)
 280		return;
 281
 282	debugfs_lookup_and_remove(dev_name(&genpd->dev), genpd_debugfs_dir);
 283}
 284
 285static void genpd_update_accounting(struct generic_pm_domain *genpd)
 286{
 287	u64 delta, now;
 288
 289	now = ktime_get_mono_fast_ns();
 290	if (now <= genpd->accounting_time)
 291		return;
 292
 293	delta = now - genpd->accounting_time;
 294
 295	/*
 296	 * If genpd->status is active, it means we are just
 297	 * out of off and so update the idle time and vice
 298	 * versa.
 299	 */
 300	if (genpd->status == GENPD_STATE_ON)
 301		genpd->states[genpd->state_idx].idle_time += delta;
 302	else
 303		genpd->on_time += delta;
 304
 305	genpd->accounting_time = now;
 306}
 307#else
 308static inline void genpd_debug_add(struct generic_pm_domain *genpd) {}
 309static inline void genpd_debug_remove(struct generic_pm_domain *genpd) {}
 310static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
 311#endif
 312
 313static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
 314					   unsigned int state)
 315{
 316	struct generic_pm_domain_data *pd_data;
 317	struct pm_domain_data *pdd;
 318	struct gpd_link *link;
 319
 320	/* New requested state is same as Max requested state */
 321	if (state == genpd->performance_state)
 322		return state;
 323
 324	/* New requested state is higher than Max requested state */
 325	if (state > genpd->performance_state)
 326		return state;
 327
 328	/* Traverse all devices within the domain */
 329	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 330		pd_data = to_gpd_data(pdd);
 331
 332		if (pd_data->performance_state > state)
 333			state = pd_data->performance_state;
 334	}
 335
 336	/*
 337	 * Traverse all sub-domains within the domain. This can be
 338	 * done without any additional locking as the link->performance_state
 339	 * field is protected by the parent genpd->lock, which is already taken.
 340	 *
 341	 * Also note that link->performance_state (subdomain's performance state
 342	 * requirement to parent domain) is different from
 343	 * link->child->performance_state (current performance state requirement
 344	 * of the devices/sub-domains of the subdomain) and so can have a
 345	 * different value.
 346	 *
 347	 * Note that we also take vote from powered-off sub-domains into account
 348	 * as the same is done for devices right now.
 349	 */
 350	list_for_each_entry(link, &genpd->parent_links, parent_node) {
 351		if (link->performance_state > state)
 352			state = link->performance_state;
 353	}
 354
 355	return state;
 356}
 357
 358static int genpd_xlate_performance_state(struct generic_pm_domain *genpd,
 359					 struct generic_pm_domain *parent,
 360					 unsigned int pstate)
 361{
 362	if (!parent->set_performance_state)
 363		return pstate;
 364
 365	return dev_pm_opp_xlate_performance_state(genpd->opp_table,
 366						  parent->opp_table,
 367						  pstate);
 368}
 369
 370static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
 371					unsigned int state, int depth);
 372
 373static void _genpd_rollback_parent_state(struct gpd_link *link, int depth)
 374{
 375	struct generic_pm_domain *parent = link->parent;
 376	int parent_state;
 377
 378	genpd_lock_nested(parent, depth + 1);
 379
 380	parent_state = link->prev_performance_state;
 381	link->performance_state = parent_state;
 382
 383	parent_state = _genpd_reeval_performance_state(parent, parent_state);
 384	if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {
 385		pr_err("%s: Failed to roll back to %d performance state\n",
 386		       parent->name, parent_state);
 387	}
 388
 389	genpd_unlock(parent);
 390}
 391
 392static int _genpd_set_parent_state(struct generic_pm_domain *genpd,
 393				   struct gpd_link *link,
 394				   unsigned int state, int depth)
 395{
 396	struct generic_pm_domain *parent = link->parent;
 
 397	int parent_state, ret;
 398
 399	/* Find parent's performance state */
 400	ret = genpd_xlate_performance_state(genpd, parent, state);
 401	if (unlikely(ret < 0))
 402		return ret;
 403
 404	parent_state = ret;
 405
 406	genpd_lock_nested(parent, depth + 1);
 407
 408	link->prev_performance_state = link->performance_state;
 409	link->performance_state = parent_state;
 
 410
 411	parent_state = _genpd_reeval_performance_state(parent, parent_state);
 412	ret = _genpd_set_performance_state(parent, parent_state, depth + 1);
 413	if (ret)
 414		link->performance_state = link->prev_performance_state;
 415
 416	genpd_unlock(parent);
 417
 418	return ret;
 419}
 420
 421static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
 422					unsigned int state, int depth)
 423{
 424	struct gpd_link *link = NULL;
 425	int ret;
 
 
 426
 427	if (state == genpd->performance_state)
 428		return 0;
 429
 430	/* When scaling up, propagate to parents first in normal order */
 431	if (state > genpd->performance_state) {
 432		list_for_each_entry(link, &genpd->child_links, child_node) {
 433			ret = _genpd_set_parent_state(genpd, link, state, depth);
 434			if (ret)
 435				goto rollback_parents_up;
 436		}
 437	}
 438
 439	if (genpd->set_performance_state) {
 440		ret = genpd->set_performance_state(genpd, state);
 441		if (ret) {
 442			if (link)
 443				goto rollback_parents_up;
 444			return ret;
 445		}
 446	}
 447
 448	/* When scaling down, propagate to parents last in reverse order */
 449	if (state < genpd->performance_state) {
 450		list_for_each_entry_reverse(link, &genpd->child_links, child_node) {
 451			ret = _genpd_set_parent_state(genpd, link, state, depth);
 452			if (ret)
 453				goto rollback_parents_down;
 454		}
 455	}
 456
 457	genpd->performance_state = state;
 458	return 0;
 459
 460rollback_parents_up:
 461	list_for_each_entry_continue_reverse(link, &genpd->child_links, child_node)
 462		_genpd_rollback_parent_state(link, depth);
 463	return ret;
 464rollback_parents_down:
 465	list_for_each_entry_continue(link, &genpd->child_links, child_node)
 466		_genpd_rollback_parent_state(link, depth);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 467	return ret;
 468}
 469
 470static int genpd_set_performance_state(struct device *dev, unsigned int state)
 471{
 472	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 473	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
 474	unsigned int prev_state;
 475	int ret;
 476
 477	prev_state = gpd_data->performance_state;
 478	if (prev_state == state)
 479		return 0;
 480
 481	gpd_data->performance_state = state;
 482	state = _genpd_reeval_performance_state(genpd, state);
 483
 484	ret = _genpd_set_performance_state(genpd, state, 0);
 485	if (ret)
 486		gpd_data->performance_state = prev_state;
 487
 488	return ret;
 489}
 490
 491static int genpd_drop_performance_state(struct device *dev)
 492{
 493	unsigned int prev_state = dev_gpd_data(dev)->performance_state;
 494
 495	if (!genpd_set_performance_state(dev, 0))
 496		return prev_state;
 497
 498	return 0;
 499}
 500
 501static void genpd_restore_performance_state(struct device *dev,
 502					    unsigned int state)
 503{
 504	if (state)
 505		genpd_set_performance_state(dev, state);
 506}
 507
 508static int genpd_dev_pm_set_performance_state(struct device *dev,
 509					      unsigned int state)
 510{
 511	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 512	int ret = 0;
 513
 514	genpd_lock(genpd);
 515	if (pm_runtime_suspended(dev)) {
 516		dev_gpd_data(dev)->rpm_pstate = state;
 517	} else {
 518		ret = genpd_set_performance_state(dev, state);
 519		if (!ret)
 520			dev_gpd_data(dev)->rpm_pstate = 0;
 521	}
 522	genpd_unlock(genpd);
 523
 524	return ret;
 525}
 526
 527/**
 528 * dev_pm_genpd_set_performance_state- Set performance state of device's power
 529 * domain.
 530 *
 531 * @dev: Device for which the performance-state needs to be set.
 532 * @state: Target performance state of the device. This can be set as 0 when the
 533 *	   device doesn't have any performance state constraints left (And so
 534 *	   the device wouldn't participate anymore to find the target
 535 *	   performance state of the genpd).
 536 *
 537 * It is assumed that the users guarantee that the genpd wouldn't be detached
 538 * while this routine is getting called.
 539 *
 540 * Returns 0 on success and negative error values on failures.
 541 */
 542int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
 543{
 544	struct generic_pm_domain *genpd;
 545
 546	genpd = dev_to_genpd_safe(dev);
 547	if (!genpd)
 548		return -ENODEV;
 549
 550	if (WARN_ON(!dev->power.subsys_data ||
 551		     !dev->power.subsys_data->domain_data))
 552		return -EINVAL;
 553
 554	return genpd_dev_pm_set_performance_state(dev, state);
 555}
 556EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
 557
 558/**
 559 * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup.
 560 *
 561 * @dev: Device to handle
 562 * @next: impending interrupt/wakeup for the device
 563 *
 564 *
 565 * Allow devices to inform of the next wakeup. It's assumed that the users
 566 * guarantee that the genpd wouldn't be detached while this routine is getting
 567 * called. Additionally, it's also assumed that @dev isn't runtime suspended
 568 * (RPM_SUSPENDED)."
 569 * Although devices are expected to update the next_wakeup after the end of
 570 * their usecase as well, it is possible the devices themselves may not know
 571 * about that, so stale @next will be ignored when powering off the domain.
 572 */
 573void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
 574{
 575	struct generic_pm_domain *genpd;
 576	struct gpd_timing_data *td;
 577
 578	genpd = dev_to_genpd_safe(dev);
 579	if (!genpd)
 580		return;
 581
 582	td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
 583	if (td)
 584		td->next_wakeup = next;
 585}
 586EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
 587
 588/**
 589 * dev_pm_genpd_get_next_hrtimer - Return the next_hrtimer for the genpd
 590 * @dev: A device that is attached to the genpd.
 591 *
 592 * This routine should typically be called for a device, at the point of when a
 593 * GENPD_NOTIFY_PRE_OFF notification has been sent for it.
 594 *
 595 * Returns the aggregated value of the genpd's next hrtimer or KTIME_MAX if no
 596 * valid value have been set.
 597 */
 598ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev)
 599{
 600	struct generic_pm_domain *genpd;
 601
 602	genpd = dev_to_genpd_safe(dev);
 603	if (!genpd)
 604		return KTIME_MAX;
 605
 606	if (genpd->gd)
 607		return genpd->gd->next_hrtimer;
 608
 609	return KTIME_MAX;
 610}
 611EXPORT_SYMBOL_GPL(dev_pm_genpd_get_next_hrtimer);
 612
 613/*
 614 * dev_pm_genpd_synced_poweroff - Next power off should be synchronous
 615 *
 616 * @dev: A device that is attached to the genpd.
 617 *
 618 * Allows a consumer of the genpd to notify the provider that the next power off
 619 * should be synchronous.
 620 *
 621 * It is assumed that the users guarantee that the genpd wouldn't be detached
 622 * while this routine is getting called.
 623 */
 624void dev_pm_genpd_synced_poweroff(struct device *dev)
 625{
 626	struct generic_pm_domain *genpd;
 627
 628	genpd = dev_to_genpd_safe(dev);
 629	if (!genpd)
 630		return;
 631
 632	genpd_lock(genpd);
 633	genpd->synced_poweroff = true;
 634	genpd_unlock(genpd);
 635}
 636EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff);
 637
 638/**
 639 * dev_pm_genpd_set_hwmode() - Set the HW mode for the device and its PM domain.
 640 *
 641 * @dev: Device for which the HW-mode should be changed.
 642 * @enable: Value to set or unset the HW-mode.
 643 *
 644 * Some PM domains can rely on HW signals to control the power for a device. To
 645 * allow a consumer driver to switch the behaviour for its device in runtime,
 646 * which may be beneficial from a latency or energy point of view, this function
 647 * may be called.
 648 *
 649 * It is assumed that the users guarantee that the genpd wouldn't be detached
 650 * while this routine is getting called.
 651 *
 652 * Return: Returns 0 on success and negative error values on failures.
 653 */
 654int dev_pm_genpd_set_hwmode(struct device *dev, bool enable)
 655{
 656	struct generic_pm_domain *genpd;
 657	int ret = 0;
 658
 659	genpd = dev_to_genpd_safe(dev);
 660	if (!genpd)
 661		return -ENODEV;
 662
 663	if (!genpd->set_hwmode_dev)
 664		return -EOPNOTSUPP;
 665
 666	genpd_lock(genpd);
 667
 668	if (dev_gpd_data(dev)->hw_mode == enable)
 669		goto out;
 670
 671	ret = genpd->set_hwmode_dev(genpd, dev, enable);
 672	if (!ret)
 673		dev_gpd_data(dev)->hw_mode = enable;
 674
 675out:
 676	genpd_unlock(genpd);
 677	return ret;
 678}
 679EXPORT_SYMBOL_GPL(dev_pm_genpd_set_hwmode);
 680
 681/**
 682 * dev_pm_genpd_get_hwmode() - Get the HW mode setting for the device.
 683 *
 684 * @dev: Device for which the current HW-mode setting should be fetched.
 685 *
 686 * This helper function allows consumer drivers to fetch the current HW mode
 687 * setting of its the device.
 688 *
 689 * It is assumed that the users guarantee that the genpd wouldn't be detached
 690 * while this routine is getting called.
 691 *
 692 * Return: Returns the HW mode setting of device from SW cached hw_mode.
 693 */
 694bool dev_pm_genpd_get_hwmode(struct device *dev)
 695{
 696	return dev_gpd_data(dev)->hw_mode;
 697}
 698EXPORT_SYMBOL_GPL(dev_pm_genpd_get_hwmode);
 699
 700static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 701{
 702	unsigned int state_idx = genpd->state_idx;
 703	ktime_t time_start;
 704	s64 elapsed_ns;
 705	int ret;
 706
 707	/* Notify consumers that we are about to power on. */
 708	ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
 709					     GENPD_NOTIFY_PRE_ON,
 710					     GENPD_NOTIFY_OFF, NULL);
 711	ret = notifier_to_errno(ret);
 712	if (ret)
 713		return ret;
 714
 715	if (!genpd->power_on)
 716		goto out;
 717
 718	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 719	if (!timed) {
 720		ret = genpd->power_on(genpd);
 721		if (ret)
 722			goto err;
 723
 724		goto out;
 725	}
 726
 727	time_start = ktime_get();
 728	ret = genpd->power_on(genpd);
 729	if (ret)
 730		goto err;
 731
 732	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 733	if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
 734		goto out;
 735
 736	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
 737	genpd->gd->max_off_time_changed = true;
 738	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 739		 dev_name(&genpd->dev), "on", elapsed_ns);
 740
 741out:
 742	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
 743	genpd->synced_poweroff = false;
 744	return 0;
 745err:
 746	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
 747				NULL);
 748	return ret;
 749}
 750
 751static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 752{
 753	unsigned int state_idx = genpd->state_idx;
 754	ktime_t time_start;
 755	s64 elapsed_ns;
 756	int ret;
 757
 758	/* Notify consumers that we are about to power off. */
 759	ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
 760					     GENPD_NOTIFY_PRE_OFF,
 761					     GENPD_NOTIFY_ON, NULL);
 762	ret = notifier_to_errno(ret);
 763	if (ret)
 764		return ret;
 765
 766	if (!genpd->power_off)
 767		goto out;
 768
 769	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 770	if (!timed) {
 771		ret = genpd->power_off(genpd);
 772		if (ret)
 773			goto busy;
 774
 775		goto out;
 776	}
 777
 778	time_start = ktime_get();
 779	ret = genpd->power_off(genpd);
 780	if (ret)
 781		goto busy;
 782
 783	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 784	if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
 785		goto out;
 786
 787	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
 788	genpd->gd->max_off_time_changed = true;
 789	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 790		 dev_name(&genpd->dev), "off", elapsed_ns);
 791
 792out:
 793	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
 794				NULL);
 795	return 0;
 796busy:
 797	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
 798	return ret;
 799}
 800
 801/**
 802 * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
 803 * @genpd: PM domain to power off.
 804 *
 805 * Queue up the execution of genpd_power_off() unless it's already been done
 806 * before.
 807 */
 808static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 809{
 810	queue_work(pm_wq, &genpd->power_off_work);
 811}
 812
 813/**
 814 * genpd_power_off - Remove power from a given PM domain.
 815 * @genpd: PM domain to power down.
 816 * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
 817 * RPM status of the releated device is in an intermediate state, not yet turned
 818 * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
 819 * be RPM_SUSPENDED, while it tries to power off the PM domain.
 820 * @depth: nesting count for lockdep.
 821 *
 822 * If all of the @genpd's devices have been suspended and all of its subdomains
 823 * have been powered down, remove power from @genpd.
 824 */
 825static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
 826			   unsigned int depth)
 827{
 828	struct pm_domain_data *pdd;
 829	struct gpd_link *link;
 830	unsigned int not_suspended = 0;
 831	int ret;
 832
 833	/*
 834	 * Do not try to power off the domain in the following situations:
 835	 * (1) The domain is already in the "power off" state.
 836	 * (2) System suspend is in progress.
 837	 */
 838	if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
 839		return 0;
 840
 841	/*
 842	 * Abort power off for the PM domain in the following situations:
 843	 * (1) The domain is configured as always on.
 844	 * (2) When the domain has a subdomain being powered on.
 845	 */
 846	if (genpd_is_always_on(genpd) ||
 847			genpd_is_rpm_always_on(genpd) ||
 848			atomic_read(&genpd->sd_count) > 0)
 849		return -EBUSY;
 850
 851	/*
 852	 * The children must be in their deepest (powered-off) states to allow
 853	 * the parent to be powered off. Note that, there's no need for
 854	 * additional locking, as powering on a child, requires the parent's
 855	 * lock to be acquired first.
 856	 */
 857	list_for_each_entry(link, &genpd->parent_links, parent_node) {
 858		struct generic_pm_domain *child = link->child;
 859		if (child->state_idx < child->state_count - 1)
 860			return -EBUSY;
 861	}
 862
 863	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 864		/*
 865		 * Do not allow PM domain to be powered off, when an IRQ safe
 866		 * device is part of a non-IRQ safe domain.
 867		 */
 868		if (!pm_runtime_suspended(pdd->dev) ||
 869			irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
 870			not_suspended++;
 871	}
 872
 873	if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
 874		return -EBUSY;
 875
 876	if (genpd->gov && genpd->gov->power_down_ok) {
 877		if (!genpd->gov->power_down_ok(&genpd->domain))
 878			return -EAGAIN;
 879	}
 880
 881	/* Default to shallowest state. */
 882	if (!genpd->gov)
 883		genpd->state_idx = 0;
 884
 885	/* Don't power off, if a child domain is waiting to power on. */
 886	if (atomic_read(&genpd->sd_count) > 0)
 887		return -EBUSY;
 888
 889	ret = _genpd_power_off(genpd, true);
 890	if (ret) {
 891		genpd->states[genpd->state_idx].rejected++;
 892		return ret;
 893	}
 894
 895	genpd->status = GENPD_STATE_OFF;
 896	genpd_update_accounting(genpd);
 897	genpd->states[genpd->state_idx].usage++;
 898
 899	list_for_each_entry(link, &genpd->child_links, child_node) {
 900		genpd_sd_counter_dec(link->parent);
 901		genpd_lock_nested(link->parent, depth + 1);
 902		genpd_power_off(link->parent, false, depth + 1);
 903		genpd_unlock(link->parent);
 904	}
 905
 906	return 0;
 907}
 908
 909/**
 910 * genpd_power_on - Restore power to a given PM domain and its parents.
 911 * @genpd: PM domain to power up.
 912 * @depth: nesting count for lockdep.
 913 *
 914 * Restore power to @genpd and all of its parents so that it is possible to
 915 * resume a device belonging to it.
 916 */
 917static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
 918{
 919	struct gpd_link *link;
 920	int ret = 0;
 921
 922	if (genpd_status_on(genpd))
 923		return 0;
 924
 925	/*
 926	 * The list is guaranteed not to change while the loop below is being
 927	 * executed, unless one of the parents' .power_on() callbacks fiddles
 928	 * with it.
 929	 */
 930	list_for_each_entry(link, &genpd->child_links, child_node) {
 931		struct generic_pm_domain *parent = link->parent;
 932
 933		genpd_sd_counter_inc(parent);
 934
 935		genpd_lock_nested(parent, depth + 1);
 936		ret = genpd_power_on(parent, depth + 1);
 937		genpd_unlock(parent);
 938
 939		if (ret) {
 940			genpd_sd_counter_dec(parent);
 941			goto err;
 942		}
 943	}
 944
 945	ret = _genpd_power_on(genpd, true);
 946	if (ret)
 947		goto err;
 948
 949	genpd->status = GENPD_STATE_ON;
 950	genpd_update_accounting(genpd);
 951
 952	return 0;
 953
 954 err:
 955	list_for_each_entry_continue_reverse(link,
 956					&genpd->child_links,
 957					child_node) {
 958		genpd_sd_counter_dec(link->parent);
 959		genpd_lock_nested(link->parent, depth + 1);
 960		genpd_power_off(link->parent, false, depth + 1);
 961		genpd_unlock(link->parent);
 962	}
 963
 964	return ret;
 965}
 966
 967static int genpd_dev_pm_start(struct device *dev)
 968{
 969	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 970
 971	return genpd_start_dev(genpd, dev);
 972}
 973
 974static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 975				     unsigned long val, void *ptr)
 976{
 977	struct generic_pm_domain_data *gpd_data;
 978	struct device *dev;
 979
 980	gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
 981	dev = gpd_data->base.dev;
 982
 983	for (;;) {
 984		struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
 985		struct pm_domain_data *pdd;
 986		struct gpd_timing_data *td;
 987
 988		spin_lock_irq(&dev->power.lock);
 989
 990		pdd = dev->power.subsys_data ?
 991				dev->power.subsys_data->domain_data : NULL;
 992		if (pdd) {
 993			td = to_gpd_data(pdd)->td;
 994			if (td) {
 995				td->constraint_changed = true;
 996				genpd = dev_to_genpd(dev);
 997			}
 998		}
 999
1000		spin_unlock_irq(&dev->power.lock);
1001
1002		if (!IS_ERR(genpd)) {
1003			genpd_lock(genpd);
1004			genpd->gd->max_off_time_changed = true;
1005			genpd_unlock(genpd);
1006		}
1007
1008		dev = dev->parent;
1009		if (!dev || dev->power.ignore_children)
1010			break;
1011	}
1012
1013	return NOTIFY_DONE;
1014}
1015
1016/**
1017 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
1018 * @work: Work structure used for scheduling the execution of this function.
1019 */
1020static void genpd_power_off_work_fn(struct work_struct *work)
1021{
1022	struct generic_pm_domain *genpd;
1023
1024	genpd = container_of(work, struct generic_pm_domain, power_off_work);
1025
1026	genpd_lock(genpd);
1027	genpd_power_off(genpd, false, 0);
1028	genpd_unlock(genpd);
1029}
1030
1031/**
1032 * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
1033 * @dev: Device to handle.
1034 */
1035static int __genpd_runtime_suspend(struct device *dev)
1036{
1037	int (*cb)(struct device *__dev);
1038
1039	if (dev->type && dev->type->pm)
1040		cb = dev->type->pm->runtime_suspend;
1041	else if (dev->class && dev->class->pm)
1042		cb = dev->class->pm->runtime_suspend;
1043	else if (dev->bus && dev->bus->pm)
1044		cb = dev->bus->pm->runtime_suspend;
1045	else
1046		cb = NULL;
1047
1048	if (!cb && dev->driver && dev->driver->pm)
1049		cb = dev->driver->pm->runtime_suspend;
1050
1051	return cb ? cb(dev) : 0;
1052}
1053
1054/**
1055 * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
1056 * @dev: Device to handle.
1057 */
1058static int __genpd_runtime_resume(struct device *dev)
1059{
1060	int (*cb)(struct device *__dev);
1061
1062	if (dev->type && dev->type->pm)
1063		cb = dev->type->pm->runtime_resume;
1064	else if (dev->class && dev->class->pm)
1065		cb = dev->class->pm->runtime_resume;
1066	else if (dev->bus && dev->bus->pm)
1067		cb = dev->bus->pm->runtime_resume;
1068	else
1069		cb = NULL;
1070
1071	if (!cb && dev->driver && dev->driver->pm)
1072		cb = dev->driver->pm->runtime_resume;
1073
1074	return cb ? cb(dev) : 0;
1075}
1076
1077/**
1078 * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
1079 * @dev: Device to suspend.
1080 *
1081 * Carry out a runtime suspend of a device under the assumption that its
1082 * pm_domain field points to the domain member of an object of type
1083 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
1084 */
1085static int genpd_runtime_suspend(struct device *dev)
1086{
1087	struct generic_pm_domain *genpd;
1088	bool (*suspend_ok)(struct device *__dev);
1089	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
1090	struct gpd_timing_data *td = gpd_data->td;
1091	bool runtime_pm = pm_runtime_enabled(dev);
1092	ktime_t time_start = 0;
1093	s64 elapsed_ns;
1094	int ret;
1095
1096	dev_dbg(dev, "%s()\n", __func__);
1097
1098	genpd = dev_to_genpd(dev);
1099	if (IS_ERR(genpd))
1100		return -EINVAL;
1101
1102	/*
1103	 * A runtime PM centric subsystem/driver may re-use the runtime PM
1104	 * callbacks for other purposes than runtime PM. In those scenarios
1105	 * runtime PM is disabled. Under these circumstances, we shall skip
1106	 * validating/measuring the PM QoS latency.
1107	 */
1108	suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
1109	if (runtime_pm && suspend_ok && !suspend_ok(dev))
1110		return -EBUSY;
1111
1112	/* Measure suspend latency. */
1113	if (td && runtime_pm)
1114		time_start = ktime_get();
1115
1116	ret = __genpd_runtime_suspend(dev);
1117	if (ret)
1118		return ret;
1119
1120	ret = genpd_stop_dev(genpd, dev);
1121	if (ret) {
1122		__genpd_runtime_resume(dev);
1123		return ret;
1124	}
1125
1126	/* Update suspend latency value if the measured time exceeds it. */
1127	if (td && runtime_pm) {
1128		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
1129		if (elapsed_ns > td->suspend_latency_ns) {
1130			td->suspend_latency_ns = elapsed_ns;
1131			dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
1132				elapsed_ns);
1133			genpd->gd->max_off_time_changed = true;
1134			td->constraint_changed = true;
1135		}
1136	}
1137
1138	/*
1139	 * If power.irq_safe is set, this routine may be run with
1140	 * IRQs disabled, so suspend only if the PM domain also is irq_safe.
1141	 */
1142	if (irq_safe_dev_in_sleep_domain(dev, genpd))
1143		return 0;
1144
1145	genpd_lock(genpd);
1146	genpd_power_off(genpd, true, 0);
1147	gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
1148	genpd_unlock(genpd);
1149
1150	return 0;
1151}
1152
1153/**
1154 * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
1155 * @dev: Device to resume.
1156 *
1157 * Carry out a runtime resume of a device under the assumption that its
1158 * pm_domain field points to the domain member of an object of type
1159 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
1160 */
1161static int genpd_runtime_resume(struct device *dev)
1162{
1163	struct generic_pm_domain *genpd;
1164	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
1165	struct gpd_timing_data *td = gpd_data->td;
1166	bool timed = td && pm_runtime_enabled(dev);
1167	ktime_t time_start = 0;
1168	s64 elapsed_ns;
1169	int ret;
1170
1171	dev_dbg(dev, "%s()\n", __func__);
1172
1173	genpd = dev_to_genpd(dev);
1174	if (IS_ERR(genpd))
1175		return -EINVAL;
1176
1177	/*
1178	 * As we don't power off a non IRQ safe domain, which holds
1179	 * an IRQ safe device, we don't need to restore power to it.
1180	 */
1181	if (irq_safe_dev_in_sleep_domain(dev, genpd))
1182		goto out;
1183
1184	genpd_lock(genpd);
1185	genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
1186	ret = genpd_power_on(genpd, 0);
1187	genpd_unlock(genpd);
1188
1189	if (ret)
1190		return ret;
1191
1192 out:
1193	/* Measure resume latency. */
1194	if (timed)
1195		time_start = ktime_get();
1196
1197	ret = genpd_start_dev(genpd, dev);
1198	if (ret)
1199		goto err_poweroff;
1200
1201	ret = __genpd_runtime_resume(dev);
1202	if (ret)
1203		goto err_stop;
1204
1205	/* Update resume latency value if the measured time exceeds it. */
1206	if (timed) {
1207		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
1208		if (elapsed_ns > td->resume_latency_ns) {
1209			td->resume_latency_ns = elapsed_ns;
1210			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
1211				elapsed_ns);
1212			genpd->gd->max_off_time_changed = true;
1213			td->constraint_changed = true;
1214		}
1215	}
1216
1217	return 0;
1218
1219err_stop:
1220	genpd_stop_dev(genpd, dev);
1221err_poweroff:
1222	if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
1223		genpd_lock(genpd);
1224		genpd_power_off(genpd, true, 0);
1225		gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
1226		genpd_unlock(genpd);
1227	}
1228
1229	return ret;
1230}
1231
1232static bool pd_ignore_unused;
1233static int __init pd_ignore_unused_setup(char *__unused)
1234{
1235	pd_ignore_unused = true;
1236	return 1;
1237}
1238__setup("pd_ignore_unused", pd_ignore_unused_setup);
1239
1240/**
1241 * genpd_power_off_unused - Power off all PM domains with no devices in use.
1242 */
1243static int __init genpd_power_off_unused(void)
1244{
1245	struct generic_pm_domain *genpd;
1246
1247	if (pd_ignore_unused) {
1248		pr_warn("genpd: Not disabling unused power domains\n");
1249		return 0;
1250	}
1251
1252	pr_info("genpd: Disabling unused power domains\n");
1253	mutex_lock(&gpd_list_lock);
1254
1255	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
1256		genpd_queue_power_off_work(genpd);
1257
1258	mutex_unlock(&gpd_list_lock);
1259
1260	return 0;
1261}
1262late_initcall_sync(genpd_power_off_unused);
1263
1264#ifdef CONFIG_PM_SLEEP
1265
1266/**
1267 * genpd_sync_power_off - Synchronously power off a PM domain and its parents.
1268 * @genpd: PM domain to power off, if possible.
1269 * @use_lock: use the lock.
1270 * @depth: nesting count for lockdep.
1271 *
1272 * Check if the given PM domain can be powered off (during system suspend or
1273 * hibernation) and do that if so.  Also, in that case propagate to its parents.
1274 *
1275 * This function is only called in "noirq" and "syscore" stages of system power
1276 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1277 * these cases the lock must be held.
1278 */
1279static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
1280				 unsigned int depth)
1281{
1282	struct gpd_link *link;
1283
1284	if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
1285		return;
1286
1287	if (genpd->suspended_count != genpd->device_count
1288	    || atomic_read(&genpd->sd_count) > 0)
1289		return;
1290
1291	/* Check that the children are in their deepest (powered-off) state. */
1292	list_for_each_entry(link, &genpd->parent_links, parent_node) {
1293		struct generic_pm_domain *child = link->child;
1294		if (child->state_idx < child->state_count - 1)
1295			return;
1296	}
1297
1298	/* Choose the deepest state when suspending */
1299	genpd->state_idx = genpd->state_count - 1;
1300	if (_genpd_power_off(genpd, false)) {
1301		genpd->states[genpd->state_idx].rejected++;
1302		return;
1303	} else {
1304		genpd->states[genpd->state_idx].usage++;
1305	}
1306
1307	genpd->status = GENPD_STATE_OFF;
1308
1309	list_for_each_entry(link, &genpd->child_links, child_node) {
1310		genpd_sd_counter_dec(link->parent);
1311
1312		if (use_lock)
1313			genpd_lock_nested(link->parent, depth + 1);
1314
1315		genpd_sync_power_off(link->parent, use_lock, depth + 1);
1316
1317		if (use_lock)
1318			genpd_unlock(link->parent);
1319	}
1320}
1321
1322/**
1323 * genpd_sync_power_on - Synchronously power on a PM domain and its parents.
1324 * @genpd: PM domain to power on.
1325 * @use_lock: use the lock.
1326 * @depth: nesting count for lockdep.
1327 *
1328 * This function is only called in "noirq" and "syscore" stages of system power
1329 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1330 * these cases the lock must be held.
1331 */
1332static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
1333				unsigned int depth)
1334{
1335	struct gpd_link *link;
1336
1337	if (genpd_status_on(genpd))
1338		return;
1339
1340	list_for_each_entry(link, &genpd->child_links, child_node) {
1341		genpd_sd_counter_inc(link->parent);
1342
1343		if (use_lock)
1344			genpd_lock_nested(link->parent, depth + 1);
1345
1346		genpd_sync_power_on(link->parent, use_lock, depth + 1);
1347
1348		if (use_lock)
1349			genpd_unlock(link->parent);
1350	}
1351
1352	_genpd_power_on(genpd, false);
1353	genpd->status = GENPD_STATE_ON;
1354}
1355
1356/**
1357 * genpd_prepare - Start power transition of a device in a PM domain.
1358 * @dev: Device to start the transition of.
1359 *
1360 * Start a power transition of a device (during a system-wide power transition)
1361 * under the assumption that its pm_domain field points to the domain member of
1362 * an object of type struct generic_pm_domain representing a PM domain
1363 * consisting of I/O devices.
1364 */
1365static int genpd_prepare(struct device *dev)
1366{
1367	struct generic_pm_domain *genpd;
1368	int ret;
1369
1370	dev_dbg(dev, "%s()\n", __func__);
1371
1372	genpd = dev_to_genpd(dev);
1373	if (IS_ERR(genpd))
1374		return -EINVAL;
1375
1376	genpd_lock(genpd);
1377	genpd->prepared_count++;
 
 
 
1378	genpd_unlock(genpd);
1379
1380	ret = pm_generic_prepare(dev);
1381	if (ret < 0) {
1382		genpd_lock(genpd);
1383
1384		genpd->prepared_count--;
1385
1386		genpd_unlock(genpd);
1387	}
1388
1389	/* Never return 1, as genpd don't cope with the direct_complete path. */
1390	return ret >= 0 ? 0 : ret;
1391}
1392
1393/**
1394 * genpd_finish_suspend - Completion of suspend or hibernation of device in an
1395 *   I/O pm domain.
1396 * @dev: Device to suspend.
1397 * @suspend_noirq: Generic suspend_noirq callback.
1398 * @resume_noirq: Generic resume_noirq callback.
1399 *
1400 * Stop the device and remove power from the domain if all devices in it have
1401 * been stopped.
1402 */
1403static int genpd_finish_suspend(struct device *dev,
1404				int (*suspend_noirq)(struct device *dev),
1405				int (*resume_noirq)(struct device *dev))
1406{
1407	struct generic_pm_domain *genpd;
1408	int ret = 0;
1409
1410	genpd = dev_to_genpd(dev);
1411	if (IS_ERR(genpd))
1412		return -EINVAL;
1413
1414	ret = suspend_noirq(dev);
1415	if (ret)
1416		return ret;
1417
1418	if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1419		return 0;
1420
1421	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1422	    !pm_runtime_status_suspended(dev)) {
1423		ret = genpd_stop_dev(genpd, dev);
1424		if (ret) {
1425			resume_noirq(dev);
1426			return ret;
1427		}
1428	}
1429
1430	genpd_lock(genpd);
1431	genpd->suspended_count++;
1432	genpd_sync_power_off(genpd, true, 0);
1433	genpd_unlock(genpd);
1434
1435	return 0;
1436}
1437
1438/**
1439 * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1440 * @dev: Device to suspend.
1441 *
1442 * Stop the device and remove power from the domain if all devices in it have
1443 * been stopped.
1444 */
1445static int genpd_suspend_noirq(struct device *dev)
1446{
1447	dev_dbg(dev, "%s()\n", __func__);
1448
1449	return genpd_finish_suspend(dev,
1450				    pm_generic_suspend_noirq,
1451				    pm_generic_resume_noirq);
1452}
1453
1454/**
1455 * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
1456 * @dev: Device to resume.
1457 * @resume_noirq: Generic resume_noirq callback.
1458 *
1459 * Restore power to the device's PM domain, if necessary, and start the device.
1460 */
1461static int genpd_finish_resume(struct device *dev,
1462			       int (*resume_noirq)(struct device *dev))
1463{
1464	struct generic_pm_domain *genpd;
1465	int ret;
1466
1467	dev_dbg(dev, "%s()\n", __func__);
1468
1469	genpd = dev_to_genpd(dev);
1470	if (IS_ERR(genpd))
1471		return -EINVAL;
1472
1473	if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1474		return resume_noirq(dev);
1475
1476	genpd_lock(genpd);
1477	genpd_sync_power_on(genpd, true, 0);
1478	genpd->suspended_count--;
1479	genpd_unlock(genpd);
1480
1481	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1482	    !pm_runtime_status_suspended(dev)) {
1483		ret = genpd_start_dev(genpd, dev);
1484		if (ret)
1485			return ret;
1486	}
1487
1488	return pm_generic_resume_noirq(dev);
1489}
1490
1491/**
1492 * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1493 * @dev: Device to resume.
1494 *
1495 * Restore power to the device's PM domain, if necessary, and start the device.
1496 */
1497static int genpd_resume_noirq(struct device *dev)
1498{
1499	dev_dbg(dev, "%s()\n", __func__);
1500
1501	return genpd_finish_resume(dev, pm_generic_resume_noirq);
1502}
1503
1504/**
1505 * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1506 * @dev: Device to freeze.
1507 *
1508 * Carry out a late freeze of a device under the assumption that its
1509 * pm_domain field points to the domain member of an object of type
1510 * struct generic_pm_domain representing a power domain consisting of I/O
1511 * devices.
1512 */
1513static int genpd_freeze_noirq(struct device *dev)
1514{
1515	dev_dbg(dev, "%s()\n", __func__);
1516
1517	return genpd_finish_suspend(dev,
1518				    pm_generic_freeze_noirq,
1519				    pm_generic_thaw_noirq);
1520}
1521
1522/**
1523 * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1524 * @dev: Device to thaw.
1525 *
1526 * Start the device, unless power has been removed from the domain already
1527 * before the system transition.
1528 */
1529static int genpd_thaw_noirq(struct device *dev)
1530{
1531	dev_dbg(dev, "%s()\n", __func__);
1532
1533	return genpd_finish_resume(dev, pm_generic_thaw_noirq);
1534}
1535
1536/**
1537 * genpd_poweroff_noirq - Completion of hibernation of device in an
1538 *   I/O PM domain.
1539 * @dev: Device to poweroff.
1540 *
1541 * Stop the device and remove power from the domain if all devices in it have
1542 * been stopped.
1543 */
1544static int genpd_poweroff_noirq(struct device *dev)
1545{
1546	dev_dbg(dev, "%s()\n", __func__);
1547
1548	return genpd_finish_suspend(dev,
1549				    pm_generic_poweroff_noirq,
1550				    pm_generic_restore_noirq);
1551}
1552
1553/**
1554 * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1555 * @dev: Device to resume.
1556 *
1557 * Make sure the domain will be in the same power state as before the
1558 * hibernation the system is resuming from and start the device if necessary.
1559 */
1560static int genpd_restore_noirq(struct device *dev)
1561{
1562	dev_dbg(dev, "%s()\n", __func__);
1563
1564	return genpd_finish_resume(dev, pm_generic_restore_noirq);
1565}
1566
1567/**
1568 * genpd_complete - Complete power transition of a device in a power domain.
1569 * @dev: Device to complete the transition of.
1570 *
1571 * Complete a power transition of a device (during a system-wide power
1572 * transition) under the assumption that its pm_domain field points to the
1573 * domain member of an object of type struct generic_pm_domain representing
1574 * a power domain consisting of I/O devices.
1575 */
1576static void genpd_complete(struct device *dev)
1577{
1578	struct generic_pm_domain *genpd;
1579
1580	dev_dbg(dev, "%s()\n", __func__);
1581
1582	genpd = dev_to_genpd(dev);
1583	if (IS_ERR(genpd))
1584		return;
1585
1586	pm_generic_complete(dev);
1587
1588	genpd_lock(genpd);
1589
1590	genpd->prepared_count--;
1591	if (!genpd->prepared_count)
1592		genpd_queue_power_off_work(genpd);
1593
1594	genpd_unlock(genpd);
1595}
1596
1597static void genpd_switch_state(struct device *dev, bool suspend)
1598{
1599	struct generic_pm_domain *genpd;
1600	bool use_lock;
1601
1602	genpd = dev_to_genpd_safe(dev);
1603	if (!genpd)
1604		return;
1605
1606	use_lock = genpd_is_irq_safe(genpd);
1607
1608	if (use_lock)
1609		genpd_lock(genpd);
1610
1611	if (suspend) {
1612		genpd->suspended_count++;
1613		genpd_sync_power_off(genpd, use_lock, 0);
1614	} else {
1615		genpd_sync_power_on(genpd, use_lock, 0);
1616		genpd->suspended_count--;
1617	}
1618
1619	if (use_lock)
1620		genpd_unlock(genpd);
1621}
1622
1623/**
1624 * dev_pm_genpd_suspend - Synchronously try to suspend the genpd for @dev
1625 * @dev: The device that is attached to the genpd, that can be suspended.
1626 *
1627 * This routine should typically be called for a device that needs to be
1628 * suspended during the syscore suspend phase. It may also be called during
1629 * suspend-to-idle to suspend a corresponding CPU device that is attached to a
1630 * genpd.
1631 */
1632void dev_pm_genpd_suspend(struct device *dev)
1633{
1634	genpd_switch_state(dev, true);
1635}
1636EXPORT_SYMBOL_GPL(dev_pm_genpd_suspend);
1637
1638/**
1639 * dev_pm_genpd_resume - Synchronously try to resume the genpd for @dev
1640 * @dev: The device that is attached to the genpd, which needs to be resumed.
1641 *
1642 * This routine should typically be called for a device that needs to be resumed
1643 * during the syscore resume phase. It may also be called during suspend-to-idle
1644 * to resume a corresponding CPU device that is attached to a genpd.
1645 */
1646void dev_pm_genpd_resume(struct device *dev)
1647{
1648	genpd_switch_state(dev, false);
1649}
1650EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
1651
1652#else /* !CONFIG_PM_SLEEP */
1653
1654#define genpd_prepare		NULL
1655#define genpd_suspend_noirq	NULL
1656#define genpd_resume_noirq	NULL
1657#define genpd_freeze_noirq	NULL
1658#define genpd_thaw_noirq	NULL
1659#define genpd_poweroff_noirq	NULL
1660#define genpd_restore_noirq	NULL
1661#define genpd_complete		NULL
1662
1663#endif /* CONFIG_PM_SLEEP */
1664
1665static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1666							   bool has_governor)
1667{
1668	struct generic_pm_domain_data *gpd_data;
1669	struct gpd_timing_data *td;
1670	int ret;
1671
1672	ret = dev_pm_get_subsys_data(dev);
1673	if (ret)
1674		return ERR_PTR(ret);
1675
1676	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1677	if (!gpd_data) {
1678		ret = -ENOMEM;
1679		goto err_put;
1680	}
1681
1682	gpd_data->base.dev = dev;
1683	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1684
1685	/* Allocate data used by a governor. */
1686	if (has_governor) {
1687		td = kzalloc(sizeof(*td), GFP_KERNEL);
1688		if (!td) {
1689			ret = -ENOMEM;
1690			goto err_free;
1691		}
1692
1693		td->constraint_changed = true;
1694		td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
1695		td->next_wakeup = KTIME_MAX;
1696		gpd_data->td = td;
1697	}
1698
1699	spin_lock_irq(&dev->power.lock);
1700
1701	if (dev->power.subsys_data->domain_data)
1702		ret = -EINVAL;
1703	else
1704		dev->power.subsys_data->domain_data = &gpd_data->base;
1705
1706	spin_unlock_irq(&dev->power.lock);
1707
1708	if (ret)
1709		goto err_free;
1710
1711	return gpd_data;
1712
1713 err_free:
1714	kfree(gpd_data->td);
1715	kfree(gpd_data);
1716 err_put:
1717	dev_pm_put_subsys_data(dev);
1718	return ERR_PTR(ret);
1719}
1720
1721static void genpd_free_dev_data(struct device *dev,
1722				struct generic_pm_domain_data *gpd_data)
1723{
1724	spin_lock_irq(&dev->power.lock);
1725
1726	dev->power.subsys_data->domain_data = NULL;
1727
1728	spin_unlock_irq(&dev->power.lock);
1729
1730	dev_pm_opp_clear_config(gpd_data->opp_token);
1731	kfree(gpd_data->td);
1732	kfree(gpd_data);
1733	dev_pm_put_subsys_data(dev);
1734}
1735
1736static void genpd_update_cpumask(struct generic_pm_domain *genpd,
1737				 int cpu, bool set, unsigned int depth)
1738{
1739	struct gpd_link *link;
1740
1741	if (!genpd_is_cpu_domain(genpd))
1742		return;
1743
1744	list_for_each_entry(link, &genpd->child_links, child_node) {
1745		struct generic_pm_domain *parent = link->parent;
1746
1747		genpd_lock_nested(parent, depth + 1);
1748		genpd_update_cpumask(parent, cpu, set, depth + 1);
1749		genpd_unlock(parent);
1750	}
1751
1752	if (set)
1753		cpumask_set_cpu(cpu, genpd->cpus);
1754	else
1755		cpumask_clear_cpu(cpu, genpd->cpus);
1756}
1757
1758static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
1759{
1760	if (cpu >= 0)
1761		genpd_update_cpumask(genpd, cpu, true, 0);
1762}
1763
1764static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
1765{
1766	if (cpu >= 0)
1767		genpd_update_cpumask(genpd, cpu, false, 0);
1768}
1769
1770static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
1771{
1772	int cpu;
1773
1774	if (!genpd_is_cpu_domain(genpd))
1775		return -1;
1776
1777	for_each_possible_cpu(cpu) {
1778		if (get_cpu_device(cpu) == dev)
1779			return cpu;
1780	}
1781
1782	return -1;
1783}
1784
1785static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1786			    struct device *base_dev)
1787{
1788	struct genpd_governor_data *gd = genpd->gd;
1789	struct generic_pm_domain_data *gpd_data;
1790	int ret;
1791
1792	dev_dbg(dev, "%s()\n", __func__);
1793
1794	gpd_data = genpd_alloc_dev_data(dev, gd);
1795	if (IS_ERR(gpd_data))
1796		return PTR_ERR(gpd_data);
1797
1798	gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
1799
1800	gpd_data->hw_mode = genpd->get_hwmode_dev ? genpd->get_hwmode_dev(genpd, dev) : false;
1801
1802	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1803	if (ret)
1804		goto out;
1805
1806	genpd_lock(genpd);
1807
1808	genpd_set_cpumask(genpd, gpd_data->cpu);
 
1809
1810	genpd->device_count++;
1811	if (gd)
1812		gd->max_off_time_changed = true;
1813
1814	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1815
1816	genpd_unlock(genpd);
1817	dev_pm_domain_set(dev, &genpd->domain);
1818 out:
1819	if (ret)
1820		genpd_free_dev_data(dev, gpd_data);
1821	else
1822		dev_pm_qos_add_notifier(dev, &gpd_data->nb,
1823					DEV_PM_QOS_RESUME_LATENCY);
1824
1825	return ret;
1826}
1827
1828/**
1829 * pm_genpd_add_device - Add a device to an I/O PM domain.
1830 * @genpd: PM domain to add the device to.
1831 * @dev: Device to be added.
1832 */
1833int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
1834{
1835	int ret;
1836
1837	if (!genpd || !dev)
1838		return -EINVAL;
1839
1840	mutex_lock(&gpd_list_lock);
1841	ret = genpd_add_device(genpd, dev, dev);
1842	mutex_unlock(&gpd_list_lock);
1843
1844	return ret;
1845}
1846EXPORT_SYMBOL_GPL(pm_genpd_add_device);
1847
1848static int genpd_remove_device(struct generic_pm_domain *genpd,
1849			       struct device *dev)
1850{
1851	struct generic_pm_domain_data *gpd_data;
1852	struct pm_domain_data *pdd;
1853	int ret = 0;
1854
1855	dev_dbg(dev, "%s()\n", __func__);
1856
1857	pdd = dev->power.subsys_data->domain_data;
1858	gpd_data = to_gpd_data(pdd);
1859	dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
1860				   DEV_PM_QOS_RESUME_LATENCY);
1861
1862	genpd_lock(genpd);
1863
1864	if (genpd->prepared_count > 0) {
1865		ret = -EAGAIN;
1866		goto out;
1867	}
1868
1869	genpd->device_count--;
1870	if (genpd->gd)
1871		genpd->gd->max_off_time_changed = true;
1872
1873	genpd_clear_cpumask(genpd, gpd_data->cpu);
 
1874
1875	list_del_init(&pdd->list_node);
1876
1877	genpd_unlock(genpd);
1878
1879	dev_pm_domain_set(dev, NULL);
1880
1881	if (genpd->detach_dev)
1882		genpd->detach_dev(genpd, dev);
1883
1884	genpd_free_dev_data(dev, gpd_data);
1885
1886	return 0;
1887
1888 out:
1889	genpd_unlock(genpd);
1890	dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
1891
1892	return ret;
1893}
1894
1895/**
1896 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1897 * @dev: Device to be removed.
1898 */
1899int pm_genpd_remove_device(struct device *dev)
1900{
1901	struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
1902
1903	if (!genpd)
1904		return -EINVAL;
1905
1906	return genpd_remove_device(genpd, dev);
1907}
1908EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1909
1910/**
1911 * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev
1912 *
1913 * @dev: Device that should be associated with the notifier
1914 * @nb: The notifier block to register
1915 *
1916 * Users may call this function to add a genpd power on/off notifier for an
1917 * attached @dev. Only one notifier per device is allowed. The notifier is
1918 * sent when genpd is powering on/off the PM domain.
1919 *
1920 * It is assumed that the user guarantee that the genpd wouldn't be detached
1921 * while this routine is getting called.
1922 *
1923 * Returns 0 on success and negative error values on failures.
1924 */
1925int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb)
1926{
1927	struct generic_pm_domain *genpd;
1928	struct generic_pm_domain_data *gpd_data;
1929	int ret;
1930
1931	genpd = dev_to_genpd_safe(dev);
1932	if (!genpd)
1933		return -ENODEV;
1934
1935	if (WARN_ON(!dev->power.subsys_data ||
1936		     !dev->power.subsys_data->domain_data))
1937		return -EINVAL;
1938
1939	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1940	if (gpd_data->power_nb)
1941		return -EEXIST;
1942
1943	genpd_lock(genpd);
1944	ret = raw_notifier_chain_register(&genpd->power_notifiers, nb);
1945	genpd_unlock(genpd);
1946
1947	if (ret) {
1948		dev_warn(dev, "failed to add notifier for PM domain %s\n",
1949			 dev_name(&genpd->dev));
1950		return ret;
1951	}
1952
1953	gpd_data->power_nb = nb;
1954	return 0;
1955}
1956EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier);
1957
1958/**
1959 * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev
1960 *
1961 * @dev: Device that is associated with the notifier
1962 *
1963 * Users may call this function to remove a genpd power on/off notifier for an
1964 * attached @dev.
1965 *
1966 * It is assumed that the user guarantee that the genpd wouldn't be detached
1967 * while this routine is getting called.
1968 *
1969 * Returns 0 on success and negative error values on failures.
1970 */
1971int dev_pm_genpd_remove_notifier(struct device *dev)
1972{
1973	struct generic_pm_domain *genpd;
1974	struct generic_pm_domain_data *gpd_data;
1975	int ret;
1976
1977	genpd = dev_to_genpd_safe(dev);
1978	if (!genpd)
1979		return -ENODEV;
1980
1981	if (WARN_ON(!dev->power.subsys_data ||
1982		     !dev->power.subsys_data->domain_data))
1983		return -EINVAL;
1984
1985	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1986	if (!gpd_data->power_nb)
1987		return -ENODEV;
1988
1989	genpd_lock(genpd);
1990	ret = raw_notifier_chain_unregister(&genpd->power_notifiers,
1991					    gpd_data->power_nb);
1992	genpd_unlock(genpd);
1993
1994	if (ret) {
1995		dev_warn(dev, "failed to remove notifier for PM domain %s\n",
1996			 dev_name(&genpd->dev));
1997		return ret;
1998	}
1999
2000	gpd_data->power_nb = NULL;
2001	return 0;
2002}
2003EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier);
2004
2005static int genpd_add_subdomain(struct generic_pm_domain *genpd,
2006			       struct generic_pm_domain *subdomain)
2007{
2008	struct gpd_link *link, *itr;
2009	int ret = 0;
2010
2011	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
2012	    || genpd == subdomain)
2013		return -EINVAL;
2014
2015	/*
2016	 * If the domain can be powered on/off in an IRQ safe
2017	 * context, ensure that the subdomain can also be
2018	 * powered on/off in that context.
2019	 */
2020	if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
2021		WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
2022		     dev_name(&genpd->dev), subdomain->name);
2023		return -EINVAL;
2024	}
2025
2026	link = kzalloc(sizeof(*link), GFP_KERNEL);
2027	if (!link)
2028		return -ENOMEM;
2029
2030	genpd_lock(subdomain);
2031	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
2032
2033	if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
2034		ret = -EINVAL;
2035		goto out;
2036	}
2037
2038	list_for_each_entry(itr, &genpd->parent_links, parent_node) {
2039		if (itr->child == subdomain && itr->parent == genpd) {
2040			ret = -EINVAL;
2041			goto out;
2042		}
2043	}
2044
2045	link->parent = genpd;
2046	list_add_tail(&link->parent_node, &genpd->parent_links);
2047	link->child = subdomain;
2048	list_add_tail(&link->child_node, &subdomain->child_links);
2049	if (genpd_status_on(subdomain))
2050		genpd_sd_counter_inc(genpd);
2051
2052 out:
2053	genpd_unlock(genpd);
2054	genpd_unlock(subdomain);
2055	if (ret)
2056		kfree(link);
2057	return ret;
2058}
2059
2060/**
2061 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
2062 * @genpd: Leader PM domain to add the subdomain to.
2063 * @subdomain: Subdomain to be added.
2064 */
2065int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
2066			   struct generic_pm_domain *subdomain)
2067{
2068	int ret;
2069
2070	mutex_lock(&gpd_list_lock);
2071	ret = genpd_add_subdomain(genpd, subdomain);
2072	mutex_unlock(&gpd_list_lock);
2073
2074	return ret;
2075}
2076EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
2077
2078/**
2079 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
2080 * @genpd: Leader PM domain to remove the subdomain from.
2081 * @subdomain: Subdomain to be removed.
2082 */
2083int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
2084			      struct generic_pm_domain *subdomain)
2085{
2086	struct gpd_link *l, *link;
2087	int ret = -EINVAL;
2088
2089	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
2090		return -EINVAL;
2091
2092	genpd_lock(subdomain);
2093	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
2094
2095	if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {
2096		pr_warn("%s: unable to remove subdomain %s\n",
2097			dev_name(&genpd->dev), subdomain->name);
2098		ret = -EBUSY;
2099		goto out;
2100	}
2101
2102	list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {
2103		if (link->child != subdomain)
2104			continue;
2105
2106		list_del(&link->parent_node);
2107		list_del(&link->child_node);
2108		kfree(link);
2109		if (genpd_status_on(subdomain))
2110			genpd_sd_counter_dec(genpd);
2111
2112		ret = 0;
2113		break;
2114	}
2115
2116out:
2117	genpd_unlock(genpd);
2118	genpd_unlock(subdomain);
2119
2120	return ret;
2121}
2122EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
2123
2124static void genpd_free_default_power_state(struct genpd_power_state *states,
2125					   unsigned int state_count)
2126{
2127	kfree(states);
2128}
2129
2130static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
2131{
2132	struct genpd_power_state *state;
2133
2134	state = kzalloc(sizeof(*state), GFP_KERNEL);
2135	if (!state)
2136		return -ENOMEM;
2137
2138	genpd->states = state;
2139	genpd->state_count = 1;
2140	genpd->free_states = genpd_free_default_power_state;
2141
2142	return 0;
2143}
2144
2145static void genpd_provider_release(struct device *dev)
2146{
2147	/* nothing to be done here */
2148}
2149
2150static int genpd_alloc_data(struct generic_pm_domain *genpd)
2151{
2152	struct genpd_governor_data *gd = NULL;
2153	int ret;
2154
2155	if (genpd_is_cpu_domain(genpd) &&
2156	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
2157		return -ENOMEM;
2158
2159	if (genpd->gov) {
2160		gd = kzalloc(sizeof(*gd), GFP_KERNEL);
2161		if (!gd) {
2162			ret = -ENOMEM;
2163			goto free;
2164		}
2165
2166		gd->max_off_time_ns = -1;
2167		gd->max_off_time_changed = true;
2168		gd->next_wakeup = KTIME_MAX;
2169		gd->next_hrtimer = KTIME_MAX;
2170	}
2171
2172	/* Use only one "off" state if there were no states declared */
2173	if (genpd->state_count == 0) {
2174		ret = genpd_set_default_power_state(genpd);
2175		if (ret)
2176			goto free;
2177	}
2178
2179	genpd->gd = gd;
2180	device_initialize(&genpd->dev);
2181	genpd->dev.release = genpd_provider_release;
2182
2183	if (!genpd_is_dev_name_fw(genpd)) {
2184		dev_set_name(&genpd->dev, "%s", genpd->name);
2185	} else {
2186		ret = ida_alloc(&genpd_ida, GFP_KERNEL);
2187		if (ret < 0)
2188			goto put;
2189
2190		genpd->device_id = ret;
2191		dev_set_name(&genpd->dev, "%s_%u", genpd->name, genpd->device_id);
2192	}
2193
2194	return 0;
2195put:
2196	put_device(&genpd->dev);
2197	if (genpd->free_states == genpd_free_default_power_state)
2198		kfree(genpd->states);
2199free:
2200	if (genpd_is_cpu_domain(genpd))
2201		free_cpumask_var(genpd->cpus);
2202	kfree(gd);
2203	return ret;
2204}
2205
2206static void genpd_free_data(struct generic_pm_domain *genpd)
2207{
2208	put_device(&genpd->dev);
2209	if (genpd->device_id != -ENXIO)
2210		ida_free(&genpd_ida, genpd->device_id);
2211	if (genpd_is_cpu_domain(genpd))
2212		free_cpumask_var(genpd->cpus);
2213	if (genpd->free_states)
2214		genpd->free_states(genpd->states, genpd->state_count);
2215	kfree(genpd->gd);
2216}
2217
2218static void genpd_lock_init(struct generic_pm_domain *genpd)
2219{
2220	if (genpd_is_cpu_domain(genpd)) {
2221		raw_spin_lock_init(&genpd->raw_slock);
2222		genpd->lock_ops = &genpd_raw_spin_ops;
2223	} else if (genpd_is_irq_safe(genpd)) {
2224		spin_lock_init(&genpd->slock);
2225		genpd->lock_ops = &genpd_spin_ops;
2226	} else {
2227		mutex_init(&genpd->mlock);
2228		genpd->lock_ops = &genpd_mtx_ops;
2229	}
2230}
2231
2232/**
2233 * pm_genpd_init - Initialize a generic I/O PM domain object.
2234 * @genpd: PM domain object to initialize.
2235 * @gov: PM domain governor to associate with the domain (may be NULL).
2236 * @is_off: Initial value of the domain's power_is_off field.
2237 *
2238 * Returns 0 on successful initialization, else a negative error code.
2239 */
2240int pm_genpd_init(struct generic_pm_domain *genpd,
2241		  struct dev_power_governor *gov, bool is_off)
2242{
2243	int ret;
2244
2245	if (IS_ERR_OR_NULL(genpd))
2246		return -EINVAL;
2247
2248	INIT_LIST_HEAD(&genpd->parent_links);
2249	INIT_LIST_HEAD(&genpd->child_links);
2250	INIT_LIST_HEAD(&genpd->dev_list);
2251	RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers);
2252	genpd_lock_init(genpd);
2253	genpd->gov = gov;
2254	INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2255	atomic_set(&genpd->sd_count, 0);
2256	genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
2257	genpd->device_count = 0;
2258	genpd->provider = NULL;
2259	genpd->device_id = -ENXIO;
2260	genpd->has_provider = false;
2261	genpd->accounting_time = ktime_get_mono_fast_ns();
2262	genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
2263	genpd->domain.ops.runtime_resume = genpd_runtime_resume;
2264	genpd->domain.ops.prepare = genpd_prepare;
2265	genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
2266	genpd->domain.ops.resume_noirq = genpd_resume_noirq;
2267	genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
2268	genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
2269	genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
2270	genpd->domain.ops.restore_noirq = genpd_restore_noirq;
2271	genpd->domain.ops.complete = genpd_complete;
2272	genpd->domain.start = genpd_dev_pm_start;
2273	genpd->domain.set_performance_state = genpd_dev_pm_set_performance_state;
2274
2275	if (genpd->flags & GENPD_FLAG_PM_CLK) {
2276		genpd->dev_ops.stop = pm_clk_suspend;
2277		genpd->dev_ops.start = pm_clk_resume;
2278	}
2279
2280	/* The always-on governor works better with the corresponding flag. */
2281	if (gov == &pm_domain_always_on_gov)
2282		genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
2283
2284	/* Always-on domains must be powered on at initialization. */
2285	if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
2286			!genpd_status_on(genpd)) {
2287		pr_err("always-on PM domain %s is not on\n", genpd->name);
2288		return -EINVAL;
2289	}
2290
2291	/* Multiple states but no governor doesn't make sense. */
2292	if (!gov && genpd->state_count > 1)
2293		pr_warn("%s: no governor for states\n", genpd->name);
2294
2295	ret = genpd_alloc_data(genpd);
2296	if (ret)
2297		return ret;
2298
 
 
 
2299	mutex_lock(&gpd_list_lock);
2300	list_add(&genpd->gpd_list_node, &gpd_list);
2301	mutex_unlock(&gpd_list_lock);
2302	genpd_debug_add(genpd);
2303
2304	return 0;
2305}
2306EXPORT_SYMBOL_GPL(pm_genpd_init);
2307
2308static int genpd_remove(struct generic_pm_domain *genpd)
2309{
2310	struct gpd_link *l, *link;
2311
2312	if (IS_ERR_OR_NULL(genpd))
2313		return -EINVAL;
2314
2315	genpd_lock(genpd);
2316
2317	if (genpd->has_provider) {
2318		genpd_unlock(genpd);
2319		pr_err("Provider present, unable to remove %s\n", dev_name(&genpd->dev));
2320		return -EBUSY;
2321	}
2322
2323	if (!list_empty(&genpd->parent_links) || genpd->device_count) {
2324		genpd_unlock(genpd);
2325		pr_err("%s: unable to remove %s\n", __func__, dev_name(&genpd->dev));
2326		return -EBUSY;
2327	}
2328
2329	list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {
2330		list_del(&link->parent_node);
2331		list_del(&link->child_node);
2332		kfree(link);
2333	}
2334
2335	list_del(&genpd->gpd_list_node);
2336	genpd_unlock(genpd);
2337	genpd_debug_remove(genpd);
2338	cancel_work_sync(&genpd->power_off_work);
2339	genpd_free_data(genpd);
2340
2341	pr_debug("%s: removed %s\n", __func__, dev_name(&genpd->dev));
2342
2343	return 0;
2344}
2345
2346/**
2347 * pm_genpd_remove - Remove a generic I/O PM domain
2348 * @genpd: Pointer to PM domain that is to be removed.
2349 *
2350 * To remove the PM domain, this function:
2351 *  - Removes the PM domain as a subdomain to any parent domains,
2352 *    if it was added.
2353 *  - Removes the PM domain from the list of registered PM domains.
2354 *
2355 * The PM domain will only be removed, if the associated provider has
2356 * been removed, it is not a parent to any other PM domain and has no
2357 * devices associated with it.
2358 */
2359int pm_genpd_remove(struct generic_pm_domain *genpd)
2360{
2361	int ret;
2362
2363	mutex_lock(&gpd_list_lock);
2364	ret = genpd_remove(genpd);
2365	mutex_unlock(&gpd_list_lock);
2366
2367	return ret;
2368}
2369EXPORT_SYMBOL_GPL(pm_genpd_remove);
2370
2371#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
2372
2373/*
2374 * Device Tree based PM domain providers.
2375 *
2376 * The code below implements generic device tree based PM domain providers that
2377 * bind device tree nodes with generic PM domains registered in the system.
2378 *
2379 * Any driver that registers generic PM domains and needs to support binding of
2380 * devices to these domains is supposed to register a PM domain provider, which
2381 * maps a PM domain specifier retrieved from the device tree to a PM domain.
2382 *
2383 * Two simple mapping functions have been provided for convenience:
2384 *  - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
2385 *  - genpd_xlate_onecell() for mapping of multiple PM domains per node by
2386 *    index.
2387 */
2388
2389/**
2390 * struct of_genpd_provider - PM domain provider registration structure
2391 * @link: Entry in global list of PM domain providers
2392 * @node: Pointer to device tree node of PM domain provider
2393 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
2394 *         into a PM domain.
2395 * @data: context pointer to be passed into @xlate callback
2396 */
2397struct of_genpd_provider {
2398	struct list_head link;
2399	struct device_node *node;
2400	genpd_xlate_t xlate;
2401	void *data;
2402};
2403
2404/* List of registered PM domain providers. */
2405static LIST_HEAD(of_genpd_providers);
2406/* Mutex to protect the list above. */
2407static DEFINE_MUTEX(of_genpd_mutex);
2408
2409/**
2410 * genpd_xlate_simple() - Xlate function for direct node-domain mapping
2411 * @genpdspec: OF phandle args to map into a PM domain
2412 * @data: xlate function private data - pointer to struct generic_pm_domain
2413 *
2414 * This is a generic xlate function that can be used to model PM domains that
2415 * have their own device tree nodes. The private data of xlate function needs
2416 * to be a valid pointer to struct generic_pm_domain.
2417 */
2418static struct generic_pm_domain *genpd_xlate_simple(
2419					const struct of_phandle_args *genpdspec,
2420					void *data)
2421{
2422	return data;
2423}
2424
2425/**
2426 * genpd_xlate_onecell() - Xlate function using a single index.
2427 * @genpdspec: OF phandle args to map into a PM domain
2428 * @data: xlate function private data - pointer to struct genpd_onecell_data
2429 *
2430 * This is a generic xlate function that can be used to model simple PM domain
2431 * controllers that have one device tree node and provide multiple PM domains.
2432 * A single cell is used as an index into an array of PM domains specified in
2433 * the genpd_onecell_data struct when registering the provider.
2434 */
2435static struct generic_pm_domain *genpd_xlate_onecell(
2436					const struct of_phandle_args *genpdspec,
2437					void *data)
2438{
2439	struct genpd_onecell_data *genpd_data = data;
2440	unsigned int idx = genpdspec->args[0];
2441
2442	if (genpdspec->args_count != 1)
2443		return ERR_PTR(-EINVAL);
2444
2445	if (idx >= genpd_data->num_domains) {
2446		pr_err("%s: invalid domain index %u\n", __func__, idx);
2447		return ERR_PTR(-EINVAL);
2448	}
2449
2450	if (!genpd_data->domains[idx])
2451		return ERR_PTR(-ENOENT);
2452
2453	return genpd_data->domains[idx];
2454}
2455
2456/**
2457 * genpd_add_provider() - Register a PM domain provider for a node
2458 * @np: Device node pointer associated with the PM domain provider.
2459 * @xlate: Callback for decoding PM domain from phandle arguments.
2460 * @data: Context pointer for @xlate callback.
2461 */
2462static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
2463			      void *data)
2464{
2465	struct of_genpd_provider *cp;
2466
2467	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
2468	if (!cp)
2469		return -ENOMEM;
2470
2471	cp->node = of_node_get(np);
2472	cp->data = data;
2473	cp->xlate = xlate;
2474	fwnode_dev_initialized(&np->fwnode, true);
2475
2476	mutex_lock(&of_genpd_mutex);
2477	list_add(&cp->link, &of_genpd_providers);
2478	mutex_unlock(&of_genpd_mutex);
2479	pr_debug("Added domain provider from %pOF\n", np);
2480
2481	return 0;
2482}
2483
2484static bool genpd_present(const struct generic_pm_domain *genpd)
2485{
2486	bool ret = false;
2487	const struct generic_pm_domain *gpd;
2488
2489	mutex_lock(&gpd_list_lock);
2490	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2491		if (gpd == genpd) {
2492			ret = true;
2493			break;
2494		}
2495	}
2496	mutex_unlock(&gpd_list_lock);
2497
2498	return ret;
2499}
2500
2501/**
2502 * of_genpd_add_provider_simple() - Register a simple PM domain provider
2503 * @np: Device node pointer associated with the PM domain provider.
2504 * @genpd: Pointer to PM domain associated with the PM domain provider.
2505 */
2506int of_genpd_add_provider_simple(struct device_node *np,
2507				 struct generic_pm_domain *genpd)
2508{
2509	int ret;
2510
2511	if (!np || !genpd)
2512		return -EINVAL;
2513
2514	if (!genpd_present(genpd))
2515		return -EINVAL;
2516
2517	genpd->dev.of_node = np;
2518
2519	/* Parse genpd OPP table */
2520	if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2521		ret = dev_pm_opp_of_add_table(&genpd->dev);
2522		if (ret)
2523			return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
2524
2525		/*
2526		 * Save table for faster processing while setting performance
2527		 * state.
2528		 */
2529		genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2530		WARN_ON(IS_ERR(genpd->opp_table));
2531	}
2532
2533	ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
2534	if (ret) {
2535		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2536			dev_pm_opp_put_opp_table(genpd->opp_table);
2537			dev_pm_opp_of_remove_table(&genpd->dev);
2538		}
2539
2540		return ret;
2541	}
2542
2543	genpd->provider = &np->fwnode;
2544	genpd->has_provider = true;
2545
2546	return 0;
2547}
2548EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
2549
2550/**
2551 * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
2552 * @np: Device node pointer associated with the PM domain provider.
2553 * @data: Pointer to the data associated with the PM domain provider.
2554 */
2555int of_genpd_add_provider_onecell(struct device_node *np,
2556				  struct genpd_onecell_data *data)
2557{
2558	struct generic_pm_domain *genpd;
2559	unsigned int i;
2560	int ret = -EINVAL;
2561
2562	if (!np || !data)
2563		return -EINVAL;
2564
2565	if (!data->xlate)
2566		data->xlate = genpd_xlate_onecell;
2567
2568	for (i = 0; i < data->num_domains; i++) {
2569		genpd = data->domains[i];
2570
2571		if (!genpd)
2572			continue;
2573		if (!genpd_present(genpd))
2574			goto error;
2575
2576		genpd->dev.of_node = np;
2577
2578		/* Parse genpd OPP table */
2579		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2580			ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
2581			if (ret) {
2582				dev_err_probe(&genpd->dev, ret,
2583					      "Failed to add OPP table for index %d\n", i);
2584				goto error;
2585			}
2586
2587			/*
2588			 * Save table for faster processing while setting
2589			 * performance state.
2590			 */
2591			genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2592			WARN_ON(IS_ERR(genpd->opp_table));
2593		}
2594
2595		genpd->provider = &np->fwnode;
2596		genpd->has_provider = true;
2597	}
2598
2599	ret = genpd_add_provider(np, data->xlate, data);
2600	if (ret < 0)
2601		goto error;
2602
2603	return 0;
2604
2605error:
2606	while (i--) {
2607		genpd = data->domains[i];
2608
2609		if (!genpd)
2610			continue;
2611
2612		genpd->provider = NULL;
2613		genpd->has_provider = false;
2614
2615		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2616			dev_pm_opp_put_opp_table(genpd->opp_table);
2617			dev_pm_opp_of_remove_table(&genpd->dev);
2618		}
2619	}
2620
2621	return ret;
2622}
2623EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
2624
2625/**
2626 * of_genpd_del_provider() - Remove a previously registered PM domain provider
2627 * @np: Device node pointer associated with the PM domain provider
2628 */
2629void of_genpd_del_provider(struct device_node *np)
2630{
2631	struct of_genpd_provider *cp, *tmp;
2632	struct generic_pm_domain *gpd;
2633
2634	mutex_lock(&gpd_list_lock);
2635	mutex_lock(&of_genpd_mutex);
2636	list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
2637		if (cp->node == np) {
2638			/*
2639			 * For each PM domain associated with the
2640			 * provider, set the 'has_provider' to false
2641			 * so that the PM domain can be safely removed.
2642			 */
2643			list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2644				if (gpd->provider == &np->fwnode) {
2645					gpd->has_provider = false;
2646
2647					if (genpd_is_opp_table_fw(gpd) || !gpd->set_performance_state)
2648						continue;
2649
2650					dev_pm_opp_put_opp_table(gpd->opp_table);
2651					dev_pm_opp_of_remove_table(&gpd->dev);
2652				}
2653			}
2654
2655			fwnode_dev_initialized(&cp->node->fwnode, false);
2656			list_del(&cp->link);
2657			of_node_put(cp->node);
2658			kfree(cp);
2659			break;
2660		}
2661	}
2662	mutex_unlock(&of_genpd_mutex);
2663	mutex_unlock(&gpd_list_lock);
2664}
2665EXPORT_SYMBOL_GPL(of_genpd_del_provider);
2666
2667/**
2668 * genpd_get_from_provider() - Look-up PM domain
2669 * @genpdspec: OF phandle args to use for look-up
2670 *
2671 * Looks for a PM domain provider under the node specified by @genpdspec and if
2672 * found, uses xlate function of the provider to map phandle args to a PM
2673 * domain.
2674 *
2675 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
2676 * on failure.
2677 */
2678static struct generic_pm_domain *genpd_get_from_provider(
2679					const struct of_phandle_args *genpdspec)
2680{
2681	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
2682	struct of_genpd_provider *provider;
2683
2684	if (!genpdspec)
2685		return ERR_PTR(-EINVAL);
2686
2687	mutex_lock(&of_genpd_mutex);
2688
2689	/* Check if we have such a provider in our array */
2690	list_for_each_entry(provider, &of_genpd_providers, link) {
2691		if (provider->node == genpdspec->np)
2692			genpd = provider->xlate(genpdspec, provider->data);
2693		if (!IS_ERR(genpd))
2694			break;
2695	}
2696
2697	mutex_unlock(&of_genpd_mutex);
2698
2699	return genpd;
2700}
2701
2702/**
2703 * of_genpd_add_device() - Add a device to an I/O PM domain
2704 * @genpdspec: OF phandle args to use for look-up PM domain
2705 * @dev: Device to be added.
2706 *
2707 * Looks-up an I/O PM domain based upon phandle args provided and adds
2708 * the device to the PM domain. Returns a negative error code on failure.
2709 */
2710int of_genpd_add_device(const struct of_phandle_args *genpdspec, struct device *dev)
2711{
2712	struct generic_pm_domain *genpd;
2713	int ret;
2714
2715	if (!dev)
2716		return -EINVAL;
2717
2718	mutex_lock(&gpd_list_lock);
2719
2720	genpd = genpd_get_from_provider(genpdspec);
2721	if (IS_ERR(genpd)) {
2722		ret = PTR_ERR(genpd);
2723		goto out;
2724	}
2725
2726	ret = genpd_add_device(genpd, dev, dev);
2727
2728out:
2729	mutex_unlock(&gpd_list_lock);
2730
2731	return ret;
2732}
2733EXPORT_SYMBOL_GPL(of_genpd_add_device);
2734
2735/**
2736 * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
2737 * @parent_spec: OF phandle args to use for parent PM domain look-up
2738 * @subdomain_spec: OF phandle args to use for subdomain look-up
2739 *
2740 * Looks-up a parent PM domain and subdomain based upon phandle args
2741 * provided and adds the subdomain to the parent PM domain. Returns a
2742 * negative error code on failure.
2743 */
2744int of_genpd_add_subdomain(const struct of_phandle_args *parent_spec,
2745			   const struct of_phandle_args *subdomain_spec)
2746{
2747	struct generic_pm_domain *parent, *subdomain;
2748	int ret;
2749
2750	mutex_lock(&gpd_list_lock);
2751
2752	parent = genpd_get_from_provider(parent_spec);
2753	if (IS_ERR(parent)) {
2754		ret = PTR_ERR(parent);
2755		goto out;
2756	}
2757
2758	subdomain = genpd_get_from_provider(subdomain_spec);
2759	if (IS_ERR(subdomain)) {
2760		ret = PTR_ERR(subdomain);
2761		goto out;
2762	}
2763
2764	ret = genpd_add_subdomain(parent, subdomain);
2765
2766out:
2767	mutex_unlock(&gpd_list_lock);
2768
2769	return ret == -ENOENT ? -EPROBE_DEFER : ret;
2770}
2771EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
2772
2773/**
2774 * of_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
2775 * @parent_spec: OF phandle args to use for parent PM domain look-up
2776 * @subdomain_spec: OF phandle args to use for subdomain look-up
2777 *
2778 * Looks-up a parent PM domain and subdomain based upon phandle args
2779 * provided and removes the subdomain from the parent PM domain. Returns a
2780 * negative error code on failure.
2781 */
2782int of_genpd_remove_subdomain(const struct of_phandle_args *parent_spec,
2783			      const struct of_phandle_args *subdomain_spec)
2784{
2785	struct generic_pm_domain *parent, *subdomain;
2786	int ret;
2787
2788	mutex_lock(&gpd_list_lock);
2789
2790	parent = genpd_get_from_provider(parent_spec);
2791	if (IS_ERR(parent)) {
2792		ret = PTR_ERR(parent);
2793		goto out;
2794	}
2795
2796	subdomain = genpd_get_from_provider(subdomain_spec);
2797	if (IS_ERR(subdomain)) {
2798		ret = PTR_ERR(subdomain);
2799		goto out;
2800	}
2801
2802	ret = pm_genpd_remove_subdomain(parent, subdomain);
2803
2804out:
2805	mutex_unlock(&gpd_list_lock);
2806
2807	return ret;
2808}
2809EXPORT_SYMBOL_GPL(of_genpd_remove_subdomain);
2810
2811/**
2812 * of_genpd_remove_last - Remove the last PM domain registered for a provider
2813 * @np: Pointer to device node associated with provider
2814 *
2815 * Find the last PM domain that was added by a particular provider and
2816 * remove this PM domain from the list of PM domains. The provider is
2817 * identified by the 'provider' device structure that is passed. The PM
2818 * domain will only be removed, if the provider associated with domain
2819 * has been removed.
2820 *
2821 * Returns a valid pointer to struct generic_pm_domain on success or
2822 * ERR_PTR() on failure.
2823 */
2824struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
2825{
2826	struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
2827	int ret;
2828
2829	if (IS_ERR_OR_NULL(np))
2830		return ERR_PTR(-EINVAL);
2831
2832	mutex_lock(&gpd_list_lock);
2833	list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
2834		if (gpd->provider == &np->fwnode) {
2835			ret = genpd_remove(gpd);
2836			genpd = ret ? ERR_PTR(ret) : gpd;
2837			break;
2838		}
2839	}
2840	mutex_unlock(&gpd_list_lock);
2841
2842	return genpd;
2843}
2844EXPORT_SYMBOL_GPL(of_genpd_remove_last);
2845
2846static void genpd_release_dev(struct device *dev)
2847{
2848	of_node_put(dev->of_node);
2849	kfree(dev);
2850}
2851
2852static const struct bus_type genpd_bus_type = {
2853	.name		= "genpd",
2854};
2855
2856/**
2857 * genpd_dev_pm_detach - Detach a device from its PM domain.
2858 * @dev: Device to detach.
2859 * @power_off: Currently not used
2860 *
2861 * Try to locate a corresponding generic PM domain, which the device was
2862 * attached to previously. If such is found, the device is detached from it.
2863 */
2864static void genpd_dev_pm_detach(struct device *dev, bool power_off)
2865{
2866	struct generic_pm_domain *pd;
2867	unsigned int i;
2868	int ret = 0;
2869
2870	pd = dev_to_genpd(dev);
2871	if (IS_ERR(pd))
2872		return;
2873
2874	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
2875
2876	/* Drop the default performance state */
2877	if (dev_gpd_data(dev)->default_pstate) {
2878		dev_pm_genpd_set_performance_state(dev, 0);
2879		dev_gpd_data(dev)->default_pstate = 0;
2880	}
2881
2882	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2883		ret = genpd_remove_device(pd, dev);
2884		if (ret != -EAGAIN)
2885			break;
2886
2887		mdelay(i);
2888		cond_resched();
2889	}
2890
2891	if (ret < 0) {
2892		dev_err(dev, "failed to remove from PM domain %s: %d",
2893			pd->name, ret);
2894		return;
2895	}
2896
2897	/* Check if PM domain can be powered off after removing this device. */
2898	genpd_queue_power_off_work(pd);
2899
2900	/* Unregister the device if it was created by genpd. */
2901	if (dev->bus == &genpd_bus_type)
2902		device_unregister(dev);
2903}
2904
2905static void genpd_dev_pm_sync(struct device *dev)
2906{
2907	struct generic_pm_domain *pd;
2908
2909	pd = dev_to_genpd(dev);
2910	if (IS_ERR(pd))
2911		return;
2912
2913	genpd_queue_power_off_work(pd);
2914}
2915
2916static int genpd_set_required_opp_dev(struct device *dev,
2917				      struct device *base_dev)
2918{
2919	struct dev_pm_opp_config config = {
2920		.required_dev = dev,
2921	};
2922	int ret;
2923
2924	/* Limit support to non-providers for now. */
2925	if (of_property_present(base_dev->of_node, "#power-domain-cells"))
2926		return 0;
2927
2928	if (!dev_pm_opp_of_has_required_opp(base_dev))
2929		return 0;
2930
2931	ret = dev_pm_opp_set_config(base_dev, &config);
2932	if (ret < 0)
2933		return ret;
2934
2935	dev_gpd_data(dev)->opp_token = ret;
2936	return 0;
2937}
2938
2939static int genpd_set_required_opp(struct device *dev, unsigned int index)
2940{
2941	int ret, pstate;
2942
2943	/* Set the default performance state */
2944	pstate = of_get_required_opp_performance_state(dev->of_node, index);
2945	if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
2946		ret = pstate;
2947		goto err;
2948	} else if (pstate > 0) {
2949		ret = dev_pm_genpd_set_performance_state(dev, pstate);
2950		if (ret)
2951			goto err;
2952		dev_gpd_data(dev)->default_pstate = pstate;
2953	}
2954
2955	return 0;
2956err:
2957	dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
2958		dev_to_genpd(dev)->name, ret);
2959	return ret;
2960}
2961
2962static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
2963				 unsigned int index, unsigned int num_domains,
2964				 bool power_on)
2965{
2966	struct of_phandle_args pd_args;
2967	struct generic_pm_domain *pd;
 
2968	int ret;
2969
2970	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
2971				"#power-domain-cells", index, &pd_args);
2972	if (ret < 0)
2973		return ret;
2974
2975	mutex_lock(&gpd_list_lock);
2976	pd = genpd_get_from_provider(&pd_args);
2977	of_node_put(pd_args.np);
2978	if (IS_ERR(pd)) {
2979		mutex_unlock(&gpd_list_lock);
2980		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
2981			__func__, PTR_ERR(pd));
2982		return driver_deferred_probe_check_state(base_dev);
2983	}
2984
2985	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
2986
2987	ret = genpd_add_device(pd, dev, base_dev);
2988	mutex_unlock(&gpd_list_lock);
2989
2990	if (ret < 0)
2991		return dev_err_probe(dev, ret, "failed to add to PM domain %s\n", pd->name);
2992
2993	dev->pm_domain->detach = genpd_dev_pm_detach;
2994	dev->pm_domain->sync = genpd_dev_pm_sync;
2995
2996	/*
2997	 * For a single PM domain the index of the required OPP must be zero, so
2998	 * let's try to assign a required dev in that case. In the multiple PM
2999	 * domains case, we need platform code to specify the index.
3000	 */
3001	if (num_domains == 1) {
3002		ret = genpd_set_required_opp_dev(dev, base_dev);
3003		if (ret)
3004			goto err;
 
3005	}
3006
3007	ret = genpd_set_required_opp(dev, index);
3008	if (ret)
3009		goto err;
3010
3011	if (power_on) {
3012		genpd_lock(pd);
3013		ret = genpd_power_on(pd, 0);
3014		genpd_unlock(pd);
3015	}
3016
3017	if (ret) {
3018		/* Drop the default performance state */
3019		if (dev_gpd_data(dev)->default_pstate) {
3020			dev_pm_genpd_set_performance_state(dev, 0);
3021			dev_gpd_data(dev)->default_pstate = 0;
3022		}
3023
3024		genpd_remove_device(pd, dev);
3025		return -EPROBE_DEFER;
3026	}
3027
3028	return 1;
3029
3030err:
 
 
3031	genpd_remove_device(pd, dev);
3032	return ret;
3033}
3034
3035/**
3036 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
3037 * @dev: Device to attach.
3038 *
3039 * Parse device's OF node to find a PM domain specifier. If such is found,
3040 * attaches the device to retrieved pm_domain ops.
3041 *
3042 * Returns 1 on successfully attached PM domain, 0 when the device don't need a
3043 * PM domain or when multiple power-domains exists for it, else a negative error
3044 * code. Note that if a power-domain exists for the device, but it cannot be
3045 * found or turned on, then return -EPROBE_DEFER to ensure that the device is
3046 * not probed and to re-try again later.
3047 */
3048int genpd_dev_pm_attach(struct device *dev)
3049{
3050	if (!dev->of_node)
3051		return 0;
3052
3053	/*
3054	 * Devices with multiple PM domains must be attached separately, as we
3055	 * can only attach one PM domain per device.
3056	 */
3057	if (of_count_phandle_with_args(dev->of_node, "power-domains",
3058				       "#power-domain-cells") != 1)
3059		return 0;
3060
3061	return __genpd_dev_pm_attach(dev, dev, 0, 1, true);
3062}
3063EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
3064
3065/**
3066 * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
3067 * @dev: The device used to lookup the PM domain.
3068 * @index: The index of the PM domain.
3069 *
3070 * Parse device's OF node to find a PM domain specifier at the provided @index.
3071 * If such is found, creates a virtual device and attaches it to the retrieved
3072 * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
3073 * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
3074 *
3075 * Returns the created virtual device if successfully attached PM domain, NULL
3076 * when the device don't need a PM domain, else an ERR_PTR() in case of
3077 * failures. If a power-domain exists for the device, but cannot be found or
3078 * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
3079 * is not probed and to re-try again later.
3080 */
3081struct device *genpd_dev_pm_attach_by_id(struct device *dev,
3082					 unsigned int index)
3083{
3084	struct device *virt_dev;
3085	int num_domains;
3086	int ret;
3087
3088	if (!dev->of_node)
3089		return NULL;
3090
3091	/* Verify that the index is within a valid range. */
3092	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
3093						 "#power-domain-cells");
3094	if (index >= num_domains)
3095		return NULL;
3096
3097	/* Allocate and register device on the genpd bus. */
3098	virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
3099	if (!virt_dev)
3100		return ERR_PTR(-ENOMEM);
3101
3102	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
3103	virt_dev->bus = &genpd_bus_type;
3104	virt_dev->release = genpd_release_dev;
3105	virt_dev->of_node = of_node_get(dev->of_node);
3106
3107	ret = device_register(virt_dev);
3108	if (ret) {
3109		put_device(virt_dev);
3110		return ERR_PTR(ret);
3111	}
3112
3113	/* Try to attach the device to the PM domain at the specified index. */
3114	ret = __genpd_dev_pm_attach(virt_dev, dev, index, num_domains, false);
3115	if (ret < 1) {
3116		device_unregister(virt_dev);
3117		return ret ? ERR_PTR(ret) : NULL;
3118	}
3119
3120	pm_runtime_enable(virt_dev);
3121	genpd_queue_power_off_work(dev_to_genpd(virt_dev));
3122
3123	return virt_dev;
3124}
3125EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
3126
3127/**
3128 * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
3129 * @dev: The device used to lookup the PM domain.
3130 * @name: The name of the PM domain.
3131 *
3132 * Parse device's OF node to find a PM domain specifier using the
3133 * power-domain-names DT property. For further description see
3134 * genpd_dev_pm_attach_by_id().
3135 */
3136struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
3137{
3138	int index;
3139
3140	if (!dev->of_node)
3141		return NULL;
3142
3143	index = of_property_match_string(dev->of_node, "power-domain-names",
3144					 name);
3145	if (index < 0)
3146		return NULL;
3147
3148	return genpd_dev_pm_attach_by_id(dev, index);
3149}
3150
3151static const struct of_device_id idle_state_match[] = {
3152	{ .compatible = "domain-idle-state", },
3153	{ }
3154};
3155
3156static int genpd_parse_state(struct genpd_power_state *genpd_state,
3157				    struct device_node *state_node)
3158{
3159	int err;
3160	u32 residency;
3161	u32 entry_latency, exit_latency;
3162
3163	err = of_property_read_u32(state_node, "entry-latency-us",
3164						&entry_latency);
3165	if (err) {
3166		pr_debug(" * %pOF missing entry-latency-us property\n",
3167			 state_node);
3168		return -EINVAL;
3169	}
3170
3171	err = of_property_read_u32(state_node, "exit-latency-us",
3172						&exit_latency);
3173	if (err) {
3174		pr_debug(" * %pOF missing exit-latency-us property\n",
3175			 state_node);
3176		return -EINVAL;
3177	}
3178
3179	err = of_property_read_u32(state_node, "min-residency-us", &residency);
3180	if (!err)
3181		genpd_state->residency_ns = 1000LL * residency;
3182
3183	genpd_state->power_on_latency_ns = 1000LL * exit_latency;
3184	genpd_state->power_off_latency_ns = 1000LL * entry_latency;
3185	genpd_state->fwnode = &state_node->fwnode;
3186
3187	return 0;
3188}
3189
3190static int genpd_iterate_idle_states(struct device_node *dn,
3191				     struct genpd_power_state *states)
3192{
3193	int ret;
3194	struct of_phandle_iterator it;
3195	struct device_node *np;
3196	int i = 0;
3197
3198	ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
3199	if (ret <= 0)
3200		return ret == -ENOENT ? 0 : ret;
3201
3202	/* Loop over the phandles until all the requested entry is found */
3203	of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
3204		np = it.node;
3205		if (!of_match_node(idle_state_match, np))
3206			continue;
3207
3208		if (!of_device_is_available(np))
3209			continue;
3210
3211		if (states) {
3212			ret = genpd_parse_state(&states[i], np);
3213			if (ret) {
3214				pr_err("Parsing idle state node %pOF failed with err %d\n",
3215				       np, ret);
3216				of_node_put(np);
3217				return ret;
3218			}
3219		}
3220		i++;
3221	}
3222
3223	return i;
3224}
3225
3226/**
3227 * of_genpd_parse_idle_states: Return array of idle states for the genpd.
3228 *
3229 * @dn: The genpd device node
3230 * @states: The pointer to which the state array will be saved.
3231 * @n: The count of elements in the array returned from this function.
3232 *
3233 * Returns the device states parsed from the OF node. The memory for the states
3234 * is allocated by this function and is the responsibility of the caller to
3235 * free the memory after use. If any or zero compatible domain idle states is
3236 * found it returns 0 and in case of errors, a negative error code is returned.
3237 */
3238int of_genpd_parse_idle_states(struct device_node *dn,
3239			struct genpd_power_state **states, int *n)
3240{
3241	struct genpd_power_state *st;
3242	int ret;
3243
3244	ret = genpd_iterate_idle_states(dn, NULL);
3245	if (ret < 0)
3246		return ret;
3247
3248	if (!ret) {
3249		*states = NULL;
3250		*n = 0;
3251		return 0;
3252	}
3253
3254	st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
3255	if (!st)
3256		return -ENOMEM;
3257
3258	ret = genpd_iterate_idle_states(dn, st);
3259	if (ret <= 0) {
3260		kfree(st);
3261		return ret < 0 ? ret : -EINVAL;
3262	}
3263
3264	*states = st;
3265	*n = ret;
3266
3267	return 0;
3268}
3269EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
3270
3271static int __init genpd_bus_init(void)
3272{
3273	return bus_register(&genpd_bus_type);
3274}
3275core_initcall(genpd_bus_init);
3276
3277#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
3278
3279
3280/***        debugfs support        ***/
3281
3282#ifdef CONFIG_DEBUG_FS
3283/*
3284 * TODO: This function is a slightly modified version of rtpm_status_show
3285 * from sysfs.c, so generalize it.
3286 */
3287static void rtpm_status_str(struct seq_file *s, struct device *dev)
3288{
3289	static const char * const status_lookup[] = {
3290		[RPM_ACTIVE] = "active",
3291		[RPM_RESUMING] = "resuming",
3292		[RPM_SUSPENDED] = "suspended",
3293		[RPM_SUSPENDING] = "suspending"
3294	};
3295	const char *p = "";
3296
3297	if (dev->power.runtime_error)
3298		p = "error";
3299	else if (dev->power.disable_depth)
3300		p = "unsupported";
3301	else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
3302		p = status_lookup[dev->power.runtime_status];
3303	else
3304		WARN_ON(1);
3305
3306	seq_printf(s, "%-26s  ", p);
3307}
3308
3309static void perf_status_str(struct seq_file *s, struct device *dev)
3310{
3311	struct generic_pm_domain_data *gpd_data;
3312
3313	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
3314
3315	seq_printf(s, "%-10u  ", gpd_data->performance_state);
3316}
3317
3318static void mode_status_str(struct seq_file *s, struct device *dev)
3319{
3320	struct generic_pm_domain_data *gpd_data;
3321
3322	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
3323
3324	seq_printf(s, "%2s", gpd_data->hw_mode ? "HW" : "SW");
3325}
3326
3327static int genpd_summary_one(struct seq_file *s,
3328			struct generic_pm_domain *genpd)
3329{
3330	static const char * const status_lookup[] = {
3331		[GENPD_STATE_ON] = "on",
3332		[GENPD_STATE_OFF] = "off"
3333	};
3334	struct pm_domain_data *pm_data;
 
3335	struct gpd_link *link;
3336	char state[16];
3337	int ret;
3338
3339	ret = genpd_lock_interruptible(genpd);
3340	if (ret)
3341		return -ERESTARTSYS;
3342
3343	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
3344		goto exit;
3345	if (!genpd_status_on(genpd))
3346		snprintf(state, sizeof(state), "%s-%u",
3347			 status_lookup[genpd->status], genpd->state_idx);
3348	else
3349		snprintf(state, sizeof(state), "%s",
3350			 status_lookup[genpd->status]);
3351	seq_printf(s, "%-30s  %-30s  %u", dev_name(&genpd->dev), state, genpd->performance_state);
3352
3353	/*
3354	 * Modifications on the list require holding locks on both
3355	 * parent and child, so we are safe.
3356	 * Also the device name is immutable.
3357	 */
3358	list_for_each_entry(link, &genpd->parent_links, parent_node) {
3359		if (list_is_first(&link->parent_node, &genpd->parent_links))
3360			seq_printf(s, "\n%48s", " ");
3361		seq_printf(s, "%s", link->child->name);
3362		if (!list_is_last(&link->parent_node, &genpd->parent_links))
3363			seq_puts(s, ", ");
3364	}
3365
3366	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
3367		seq_printf(s, "\n    %-30s  ", dev_name(pm_data->dev));
 
 
 
 
 
 
3368		rtpm_status_str(s, pm_data->dev);
3369		perf_status_str(s, pm_data->dev);
3370		mode_status_str(s, pm_data->dev);
3371	}
3372
3373	seq_puts(s, "\n");
3374exit:
3375	genpd_unlock(genpd);
3376
3377	return 0;
3378}
3379
3380static int summary_show(struct seq_file *s, void *data)
3381{
3382	struct generic_pm_domain *genpd;
3383	int ret = 0;
3384
3385	seq_puts(s, "domain                          status          children        performance\n");
3386	seq_puts(s, "    /device                         runtime status                  managed by\n");
3387	seq_puts(s, "------------------------------------------------------------------------------\n");
3388
3389	ret = mutex_lock_interruptible(&gpd_list_lock);
3390	if (ret)
3391		return -ERESTARTSYS;
3392
3393	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
3394		ret = genpd_summary_one(s, genpd);
3395		if (ret)
3396			break;
3397	}
3398	mutex_unlock(&gpd_list_lock);
3399
3400	return ret;
3401}
3402
3403static int status_show(struct seq_file *s, void *data)
3404{
3405	static const char * const status_lookup[] = {
3406		[GENPD_STATE_ON] = "on",
3407		[GENPD_STATE_OFF] = "off"
3408	};
3409
3410	struct generic_pm_domain *genpd = s->private;
3411	int ret = 0;
3412
3413	ret = genpd_lock_interruptible(genpd);
3414	if (ret)
3415		return -ERESTARTSYS;
3416
3417	if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
3418		goto exit;
3419
3420	if (genpd->status == GENPD_STATE_OFF)
3421		seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
3422			genpd->state_idx);
3423	else
3424		seq_printf(s, "%s\n", status_lookup[genpd->status]);
3425exit:
3426	genpd_unlock(genpd);
3427	return ret;
3428}
3429
3430static int sub_domains_show(struct seq_file *s, void *data)
3431{
3432	struct generic_pm_domain *genpd = s->private;
3433	struct gpd_link *link;
3434	int ret = 0;
3435
3436	ret = genpd_lock_interruptible(genpd);
3437	if (ret)
3438		return -ERESTARTSYS;
3439
3440	list_for_each_entry(link, &genpd->parent_links, parent_node)
3441		seq_printf(s, "%s\n", link->child->name);
3442
3443	genpd_unlock(genpd);
3444	return ret;
3445}
3446
3447static int idle_states_show(struct seq_file *s, void *data)
3448{
3449	struct generic_pm_domain *genpd = s->private;
3450	u64 now, delta, idle_time = 0;
3451	unsigned int i;
3452	int ret = 0;
3453
3454	ret = genpd_lock_interruptible(genpd);
3455	if (ret)
3456		return -ERESTARTSYS;
3457
3458	seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
3459
3460	for (i = 0; i < genpd->state_count; i++) {
3461		idle_time += genpd->states[i].idle_time;
3462
3463		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3464			now = ktime_get_mono_fast_ns();
3465			if (now > genpd->accounting_time) {
3466				delta = now - genpd->accounting_time;
3467				idle_time += delta;
3468			}
3469		}
3470
3471		do_div(idle_time, NSEC_PER_MSEC);
3472		seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
3473			   genpd->states[i].usage, genpd->states[i].rejected);
3474	}
3475
3476	genpd_unlock(genpd);
3477	return ret;
3478}
3479
3480static int active_time_show(struct seq_file *s, void *data)
3481{
3482	struct generic_pm_domain *genpd = s->private;
3483	u64 now, on_time, delta = 0;
3484	int ret = 0;
3485
3486	ret = genpd_lock_interruptible(genpd);
3487	if (ret)
3488		return -ERESTARTSYS;
3489
3490	if (genpd->status == GENPD_STATE_ON) {
3491		now = ktime_get_mono_fast_ns();
3492		if (now > genpd->accounting_time)
3493			delta = now - genpd->accounting_time;
3494	}
3495
3496	on_time = genpd->on_time + delta;
3497	do_div(on_time, NSEC_PER_MSEC);
3498	seq_printf(s, "%llu ms\n", on_time);
3499
3500	genpd_unlock(genpd);
3501	return ret;
3502}
3503
3504static int total_idle_time_show(struct seq_file *s, void *data)
3505{
3506	struct generic_pm_domain *genpd = s->private;
3507	u64 now, delta, total = 0;
3508	unsigned int i;
3509	int ret = 0;
3510
3511	ret = genpd_lock_interruptible(genpd);
3512	if (ret)
3513		return -ERESTARTSYS;
3514
3515	for (i = 0; i < genpd->state_count; i++) {
3516		total += genpd->states[i].idle_time;
3517
3518		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3519			now = ktime_get_mono_fast_ns();
3520			if (now > genpd->accounting_time) {
3521				delta = now - genpd->accounting_time;
3522				total += delta;
3523			}
3524		}
3525	}
3526
3527	do_div(total, NSEC_PER_MSEC);
3528	seq_printf(s, "%llu ms\n", total);
3529
3530	genpd_unlock(genpd);
3531	return ret;
3532}
3533
3534
3535static int devices_show(struct seq_file *s, void *data)
3536{
3537	struct generic_pm_domain *genpd = s->private;
3538	struct pm_domain_data *pm_data;
 
3539	int ret = 0;
3540
3541	ret = genpd_lock_interruptible(genpd);
3542	if (ret)
3543		return -ERESTARTSYS;
3544
3545	list_for_each_entry(pm_data, &genpd->dev_list, list_node)
3546		seq_printf(s, "%s\n", dev_name(pm_data->dev));
 
 
 
 
 
 
 
 
3547
3548	genpd_unlock(genpd);
3549	return ret;
3550}
3551
3552static int perf_state_show(struct seq_file *s, void *data)
3553{
3554	struct generic_pm_domain *genpd = s->private;
3555
3556	if (genpd_lock_interruptible(genpd))
3557		return -ERESTARTSYS;
3558
3559	seq_printf(s, "%u\n", genpd->performance_state);
3560
3561	genpd_unlock(genpd);
3562	return 0;
3563}
3564
3565DEFINE_SHOW_ATTRIBUTE(summary);
3566DEFINE_SHOW_ATTRIBUTE(status);
3567DEFINE_SHOW_ATTRIBUTE(sub_domains);
3568DEFINE_SHOW_ATTRIBUTE(idle_states);
3569DEFINE_SHOW_ATTRIBUTE(active_time);
3570DEFINE_SHOW_ATTRIBUTE(total_idle_time);
3571DEFINE_SHOW_ATTRIBUTE(devices);
3572DEFINE_SHOW_ATTRIBUTE(perf_state);
3573
3574static void genpd_debug_add(struct generic_pm_domain *genpd)
3575{
3576	struct dentry *d;
3577
3578	if (!genpd_debugfs_dir)
3579		return;
3580
3581	d = debugfs_create_dir(dev_name(&genpd->dev), genpd_debugfs_dir);
3582
3583	debugfs_create_file("current_state", 0444,
3584			    d, genpd, &status_fops);
3585	debugfs_create_file("sub_domains", 0444,
3586			    d, genpd, &sub_domains_fops);
3587	debugfs_create_file("idle_states", 0444,
3588			    d, genpd, &idle_states_fops);
3589	debugfs_create_file("active_time", 0444,
3590			    d, genpd, &active_time_fops);
3591	debugfs_create_file("total_idle_time", 0444,
3592			    d, genpd, &total_idle_time_fops);
3593	debugfs_create_file("devices", 0444,
3594			    d, genpd, &devices_fops);
3595	if (genpd->set_performance_state)
3596		debugfs_create_file("perf_state", 0444,
3597				    d, genpd, &perf_state_fops);
3598}
3599
3600static int __init genpd_debug_init(void)
3601{
3602	struct generic_pm_domain *genpd;
3603
3604	genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
3605
3606	debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
3607			    NULL, &summary_fops);
3608
3609	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
3610		genpd_debug_add(genpd);
3611
3612	return 0;
3613}
3614late_initcall(genpd_debug_init);
3615
3616static void __exit genpd_debug_exit(void)
3617{
3618	debugfs_remove_recursive(genpd_debugfs_dir);
3619}
3620__exitcall(genpd_debug_exit);
3621#endif /* CONFIG_DEBUG_FS */
v6.8
   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#include <linux/debugfs.h>
  25
 
 
 
  26#define GENPD_RETRY_MAX_MS	250		/* Approximate */
  27
  28#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)		\
  29({								\
  30	type (*__routine)(struct device *__d); 			\
  31	type __ret = (type)0;					\
  32								\
  33	__routine = genpd->dev_ops.callback; 			\
  34	if (__routine) {					\
  35		__ret = __routine(dev); 			\
  36	}							\
  37	__ret;							\
  38})
  39
  40static LIST_HEAD(gpd_list);
  41static DEFINE_MUTEX(gpd_list_lock);
  42
  43struct genpd_lock_ops {
  44	void (*lock)(struct generic_pm_domain *genpd);
  45	void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
  46	int (*lock_interruptible)(struct generic_pm_domain *genpd);
  47	void (*unlock)(struct generic_pm_domain *genpd);
  48};
  49
  50static void genpd_lock_mtx(struct generic_pm_domain *genpd)
  51{
  52	mutex_lock(&genpd->mlock);
  53}
  54
  55static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
  56					int depth)
  57{
  58	mutex_lock_nested(&genpd->mlock, depth);
  59}
  60
  61static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
  62{
  63	return mutex_lock_interruptible(&genpd->mlock);
  64}
  65
  66static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
  67{
  68	return mutex_unlock(&genpd->mlock);
  69}
  70
  71static const struct genpd_lock_ops genpd_mtx_ops = {
  72	.lock = genpd_lock_mtx,
  73	.lock_nested = genpd_lock_nested_mtx,
  74	.lock_interruptible = genpd_lock_interruptible_mtx,
  75	.unlock = genpd_unlock_mtx,
  76};
  77
  78static void genpd_lock_spin(struct generic_pm_domain *genpd)
  79	__acquires(&genpd->slock)
  80{
  81	unsigned long flags;
  82
  83	spin_lock_irqsave(&genpd->slock, flags);
  84	genpd->lock_flags = flags;
  85}
  86
  87static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
  88					int depth)
  89	__acquires(&genpd->slock)
  90{
  91	unsigned long flags;
  92
  93	spin_lock_irqsave_nested(&genpd->slock, flags, depth);
  94	genpd->lock_flags = flags;
  95}
  96
  97static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
  98	__acquires(&genpd->slock)
  99{
 100	unsigned long flags;
 101
 102	spin_lock_irqsave(&genpd->slock, flags);
 103	genpd->lock_flags = flags;
 104	return 0;
 105}
 106
 107static void genpd_unlock_spin(struct generic_pm_domain *genpd)
 108	__releases(&genpd->slock)
 109{
 110	spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
 111}
 112
 113static const struct genpd_lock_ops genpd_spin_ops = {
 114	.lock = genpd_lock_spin,
 115	.lock_nested = genpd_lock_nested_spin,
 116	.lock_interruptible = genpd_lock_interruptible_spin,
 117	.unlock = genpd_unlock_spin,
 118};
 119
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 120#define genpd_lock(p)			p->lock_ops->lock(p)
 121#define genpd_lock_nested(p, d)		p->lock_ops->lock_nested(p, d)
 122#define genpd_lock_interruptible(p)	p->lock_ops->lock_interruptible(p)
 123#define genpd_unlock(p)			p->lock_ops->unlock(p)
 124
 125#define genpd_status_on(genpd)		(genpd->status == GENPD_STATE_ON)
 126#define genpd_is_irq_safe(genpd)	(genpd->flags & GENPD_FLAG_IRQ_SAFE)
 127#define genpd_is_always_on(genpd)	(genpd->flags & GENPD_FLAG_ALWAYS_ON)
 128#define genpd_is_active_wakeup(genpd)	(genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
 129#define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
 130#define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
 131#define genpd_is_opp_table_fw(genpd)	(genpd->flags & GENPD_FLAG_OPP_TABLE_FW)
 
 132
 133static inline bool irq_safe_dev_in_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 domain, which
 142	 * callbacks are allowed to sleep. This indicates a suboptimal
 143	 * configuration for PM, but it doesn't matter for an always on domain.
 144	 */
 145	if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
 146		return ret;
 147
 148	if (ret)
 149		dev_warn_once(dev, "PM domain %s will not be powered off\n",
 150				genpd->name);
 151
 152	return ret;
 153}
 154
 155static int genpd_runtime_suspend(struct device *dev);
 156
 157/*
 158 * Get the generic PM domain for a particular struct device.
 159 * This validates the struct device pointer, the PM domain pointer,
 160 * and checks that the PM domain pointer is a real generic PM domain.
 161 * Any failure results in NULL being returned.
 162 */
 163static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
 164{
 165	if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
 166		return NULL;
 167
 168	/* A genpd's always have its ->runtime_suspend() callback assigned. */
 169	if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
 170		return pd_to_genpd(dev->pm_domain);
 171
 172	return NULL;
 173}
 174
 175/*
 176 * This should only be used where we are certain that the pm_domain
 177 * attached to the device is a genpd domain.
 178 */
 179static struct generic_pm_domain *dev_to_genpd(struct device *dev)
 180{
 181	if (IS_ERR_OR_NULL(dev->pm_domain))
 182		return ERR_PTR(-EINVAL);
 183
 184	return pd_to_genpd(dev->pm_domain);
 185}
 186
 
 
 
 
 
 
 
 
 
 
 187static int genpd_stop_dev(const struct generic_pm_domain *genpd,
 188			  struct device *dev)
 189{
 190	return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
 191}
 192
 193static int genpd_start_dev(const struct generic_pm_domain *genpd,
 194			   struct device *dev)
 195{
 196	return GENPD_DEV_CALLBACK(genpd, int, start, dev);
 197}
 198
 199static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
 200{
 201	bool ret = false;
 202
 203	if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
 204		ret = !!atomic_dec_and_test(&genpd->sd_count);
 205
 206	return ret;
 207}
 208
 209static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
 210{
 211	atomic_inc(&genpd->sd_count);
 212	smp_mb__after_atomic();
 213}
 214
 215#ifdef CONFIG_DEBUG_FS
 216static struct dentry *genpd_debugfs_dir;
 217
 218static void genpd_debug_add(struct generic_pm_domain *genpd);
 219
 220static void genpd_debug_remove(struct generic_pm_domain *genpd)
 221{
 222	if (!genpd_debugfs_dir)
 223		return;
 224
 225	debugfs_lookup_and_remove(genpd->name, genpd_debugfs_dir);
 226}
 227
 228static void genpd_update_accounting(struct generic_pm_domain *genpd)
 229{
 230	u64 delta, now;
 231
 232	now = ktime_get_mono_fast_ns();
 233	if (now <= genpd->accounting_time)
 234		return;
 235
 236	delta = now - genpd->accounting_time;
 237
 238	/*
 239	 * If genpd->status is active, it means we are just
 240	 * out of off and so update the idle time and vice
 241	 * versa.
 242	 */
 243	if (genpd->status == GENPD_STATE_ON)
 244		genpd->states[genpd->state_idx].idle_time += delta;
 245	else
 246		genpd->on_time += delta;
 247
 248	genpd->accounting_time = now;
 249}
 250#else
 251static inline void genpd_debug_add(struct generic_pm_domain *genpd) {}
 252static inline void genpd_debug_remove(struct generic_pm_domain *genpd) {}
 253static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
 254#endif
 255
 256static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
 257					   unsigned int state)
 258{
 259	struct generic_pm_domain_data *pd_data;
 260	struct pm_domain_data *pdd;
 261	struct gpd_link *link;
 262
 263	/* New requested state is same as Max requested state */
 264	if (state == genpd->performance_state)
 265		return state;
 266
 267	/* New requested state is higher than Max requested state */
 268	if (state > genpd->performance_state)
 269		return state;
 270
 271	/* Traverse all devices within the domain */
 272	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 273		pd_data = to_gpd_data(pdd);
 274
 275		if (pd_data->performance_state > state)
 276			state = pd_data->performance_state;
 277	}
 278
 279	/*
 280	 * Traverse all sub-domains within the domain. This can be
 281	 * done without any additional locking as the link->performance_state
 282	 * field is protected by the parent genpd->lock, which is already taken.
 283	 *
 284	 * Also note that link->performance_state (subdomain's performance state
 285	 * requirement to parent domain) is different from
 286	 * link->child->performance_state (current performance state requirement
 287	 * of the devices/sub-domains of the subdomain) and so can have a
 288	 * different value.
 289	 *
 290	 * Note that we also take vote from powered-off sub-domains into account
 291	 * as the same is done for devices right now.
 292	 */
 293	list_for_each_entry(link, &genpd->parent_links, parent_node) {
 294		if (link->performance_state > state)
 295			state = link->performance_state;
 296	}
 297
 298	return state;
 299}
 300
 301static int genpd_xlate_performance_state(struct generic_pm_domain *genpd,
 302					 struct generic_pm_domain *parent,
 303					 unsigned int pstate)
 304{
 305	if (!parent->set_performance_state)
 306		return pstate;
 307
 308	return dev_pm_opp_xlate_performance_state(genpd->opp_table,
 309						  parent->opp_table,
 310						  pstate);
 311}
 312
 313static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
 314					unsigned int state, int depth)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 315{
 316	struct generic_pm_domain *parent;
 317	struct gpd_link *link;
 318	int parent_state, ret;
 319
 320	if (state == genpd->performance_state)
 321		return 0;
 
 
 
 
 
 
 322
 323	/* Propagate to parents of genpd */
 324	list_for_each_entry(link, &genpd->child_links, child_node) {
 325		parent = link->parent;
 326
 327		/* Find parent's performance state */
 328		ret = genpd_xlate_performance_state(genpd, parent, state);
 329		if (unlikely(ret < 0))
 330			goto err;
 331
 332		parent_state = ret;
 333
 334		genpd_lock_nested(parent, depth + 1);
 
 335
 336		link->prev_performance_state = link->performance_state;
 337		link->performance_state = parent_state;
 338		parent_state = _genpd_reeval_performance_state(parent,
 339						parent_state);
 340		ret = _genpd_set_performance_state(parent, parent_state, depth + 1);
 341		if (ret)
 342			link->performance_state = link->prev_performance_state;
 343
 344		genpd_unlock(parent);
 
 345
 346		if (ret)
 347			goto err;
 
 
 
 
 
 348	}
 349
 350	if (genpd->set_performance_state) {
 351		ret = genpd->set_performance_state(genpd, state);
 352		if (ret)
 353			goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 354	}
 355
 356	genpd->performance_state = state;
 357	return 0;
 358
 359err:
 360	/* Encountered an error, lets rollback */
 361	list_for_each_entry_continue_reverse(link, &genpd->child_links,
 362					     child_node) {
 363		parent = link->parent;
 364
 365		genpd_lock_nested(parent, depth + 1);
 366
 367		parent_state = link->prev_performance_state;
 368		link->performance_state = parent_state;
 369
 370		parent_state = _genpd_reeval_performance_state(parent,
 371						parent_state);
 372		if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {
 373			pr_err("%s: Failed to roll back to %d performance state\n",
 374			       parent->name, parent_state);
 375		}
 376
 377		genpd_unlock(parent);
 378	}
 379
 380	return ret;
 381}
 382
 383static int genpd_set_performance_state(struct device *dev, unsigned int state)
 384{
 385	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 386	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
 387	unsigned int prev_state;
 388	int ret;
 389
 390	prev_state = gpd_data->performance_state;
 391	if (prev_state == state)
 392		return 0;
 393
 394	gpd_data->performance_state = state;
 395	state = _genpd_reeval_performance_state(genpd, state);
 396
 397	ret = _genpd_set_performance_state(genpd, state, 0);
 398	if (ret)
 399		gpd_data->performance_state = prev_state;
 400
 401	return ret;
 402}
 403
 404static int genpd_drop_performance_state(struct device *dev)
 405{
 406	unsigned int prev_state = dev_gpd_data(dev)->performance_state;
 407
 408	if (!genpd_set_performance_state(dev, 0))
 409		return prev_state;
 410
 411	return 0;
 412}
 413
 414static void genpd_restore_performance_state(struct device *dev,
 415					    unsigned int state)
 416{
 417	if (state)
 418		genpd_set_performance_state(dev, state);
 419}
 420
 421static int genpd_dev_pm_set_performance_state(struct device *dev,
 422					      unsigned int state)
 423{
 424	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 425	int ret = 0;
 426
 427	genpd_lock(genpd);
 428	if (pm_runtime_suspended(dev)) {
 429		dev_gpd_data(dev)->rpm_pstate = state;
 430	} else {
 431		ret = genpd_set_performance_state(dev, state);
 432		if (!ret)
 433			dev_gpd_data(dev)->rpm_pstate = 0;
 434	}
 435	genpd_unlock(genpd);
 436
 437	return ret;
 438}
 439
 440/**
 441 * dev_pm_genpd_set_performance_state- Set performance state of device's power
 442 * domain.
 443 *
 444 * @dev: Device for which the performance-state needs to be set.
 445 * @state: Target performance state of the device. This can be set as 0 when the
 446 *	   device doesn't have any performance state constraints left (And so
 447 *	   the device wouldn't participate anymore to find the target
 448 *	   performance state of the genpd).
 449 *
 450 * It is assumed that the users guarantee that the genpd wouldn't be detached
 451 * while this routine is getting called.
 452 *
 453 * Returns 0 on success and negative error values on failures.
 454 */
 455int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
 456{
 457	struct generic_pm_domain *genpd;
 458
 459	genpd = dev_to_genpd_safe(dev);
 460	if (!genpd)
 461		return -ENODEV;
 462
 463	if (WARN_ON(!dev->power.subsys_data ||
 464		     !dev->power.subsys_data->domain_data))
 465		return -EINVAL;
 466
 467	return genpd_dev_pm_set_performance_state(dev, state);
 468}
 469EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
 470
 471/**
 472 * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup.
 473 *
 474 * @dev: Device to handle
 475 * @next: impending interrupt/wakeup for the device
 476 *
 477 *
 478 * Allow devices to inform of the next wakeup. It's assumed that the users
 479 * guarantee that the genpd wouldn't be detached while this routine is getting
 480 * called. Additionally, it's also assumed that @dev isn't runtime suspended
 481 * (RPM_SUSPENDED)."
 482 * Although devices are expected to update the next_wakeup after the end of
 483 * their usecase as well, it is possible the devices themselves may not know
 484 * about that, so stale @next will be ignored when powering off the domain.
 485 */
 486void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
 487{
 488	struct generic_pm_domain *genpd;
 489	struct gpd_timing_data *td;
 490
 491	genpd = dev_to_genpd_safe(dev);
 492	if (!genpd)
 493		return;
 494
 495	td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
 496	if (td)
 497		td->next_wakeup = next;
 498}
 499EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
 500
 501/**
 502 * dev_pm_genpd_get_next_hrtimer - Return the next_hrtimer for the genpd
 503 * @dev: A device that is attached to the genpd.
 504 *
 505 * This routine should typically be called for a device, at the point of when a
 506 * GENPD_NOTIFY_PRE_OFF notification has been sent for it.
 507 *
 508 * Returns the aggregated value of the genpd's next hrtimer or KTIME_MAX if no
 509 * valid value have been set.
 510 */
 511ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev)
 512{
 513	struct generic_pm_domain *genpd;
 514
 515	genpd = dev_to_genpd_safe(dev);
 516	if (!genpd)
 517		return KTIME_MAX;
 518
 519	if (genpd->gd)
 520		return genpd->gd->next_hrtimer;
 521
 522	return KTIME_MAX;
 523}
 524EXPORT_SYMBOL_GPL(dev_pm_genpd_get_next_hrtimer);
 525
 526/*
 527 * dev_pm_genpd_synced_poweroff - Next power off should be synchronous
 528 *
 529 * @dev: A device that is attached to the genpd.
 530 *
 531 * Allows a consumer of the genpd to notify the provider that the next power off
 532 * should be synchronous.
 533 *
 534 * It is assumed that the users guarantee that the genpd wouldn't be detached
 535 * while this routine is getting called.
 536 */
 537void dev_pm_genpd_synced_poweroff(struct device *dev)
 538{
 539	struct generic_pm_domain *genpd;
 540
 541	genpd = dev_to_genpd_safe(dev);
 542	if (!genpd)
 543		return;
 544
 545	genpd_lock(genpd);
 546	genpd->synced_poweroff = true;
 547	genpd_unlock(genpd);
 548}
 549EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff);
 550
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 551static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 552{
 553	unsigned int state_idx = genpd->state_idx;
 554	ktime_t time_start;
 555	s64 elapsed_ns;
 556	int ret;
 557
 558	/* Notify consumers that we are about to power on. */
 559	ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
 560					     GENPD_NOTIFY_PRE_ON,
 561					     GENPD_NOTIFY_OFF, NULL);
 562	ret = notifier_to_errno(ret);
 563	if (ret)
 564		return ret;
 565
 566	if (!genpd->power_on)
 567		goto out;
 568
 569	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 570	if (!timed) {
 571		ret = genpd->power_on(genpd);
 572		if (ret)
 573			goto err;
 574
 575		goto out;
 576	}
 577
 578	time_start = ktime_get();
 579	ret = genpd->power_on(genpd);
 580	if (ret)
 581		goto err;
 582
 583	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 584	if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
 585		goto out;
 586
 587	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
 588	genpd->gd->max_off_time_changed = true;
 589	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 590		 genpd->name, "on", elapsed_ns);
 591
 592out:
 593	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
 594	genpd->synced_poweroff = false;
 595	return 0;
 596err:
 597	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
 598				NULL);
 599	return ret;
 600}
 601
 602static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 603{
 604	unsigned int state_idx = genpd->state_idx;
 605	ktime_t time_start;
 606	s64 elapsed_ns;
 607	int ret;
 608
 609	/* Notify consumers that we are about to power off. */
 610	ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
 611					     GENPD_NOTIFY_PRE_OFF,
 612					     GENPD_NOTIFY_ON, NULL);
 613	ret = notifier_to_errno(ret);
 614	if (ret)
 615		return ret;
 616
 617	if (!genpd->power_off)
 618		goto out;
 619
 620	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 621	if (!timed) {
 622		ret = genpd->power_off(genpd);
 623		if (ret)
 624			goto busy;
 625
 626		goto out;
 627	}
 628
 629	time_start = ktime_get();
 630	ret = genpd->power_off(genpd);
 631	if (ret)
 632		goto busy;
 633
 634	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 635	if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
 636		goto out;
 637
 638	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
 639	genpd->gd->max_off_time_changed = true;
 640	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 641		 genpd->name, "off", elapsed_ns);
 642
 643out:
 644	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
 645				NULL);
 646	return 0;
 647busy:
 648	raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
 649	return ret;
 650}
 651
 652/**
 653 * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
 654 * @genpd: PM domain to power off.
 655 *
 656 * Queue up the execution of genpd_power_off() unless it's already been done
 657 * before.
 658 */
 659static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 660{
 661	queue_work(pm_wq, &genpd->power_off_work);
 662}
 663
 664/**
 665 * genpd_power_off - Remove power from a given PM domain.
 666 * @genpd: PM domain to power down.
 667 * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
 668 * RPM status of the releated device is in an intermediate state, not yet turned
 669 * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
 670 * be RPM_SUSPENDED, while it tries to power off the PM domain.
 671 * @depth: nesting count for lockdep.
 672 *
 673 * If all of the @genpd's devices have been suspended and all of its subdomains
 674 * have been powered down, remove power from @genpd.
 675 */
 676static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
 677			   unsigned int depth)
 678{
 679	struct pm_domain_data *pdd;
 680	struct gpd_link *link;
 681	unsigned int not_suspended = 0;
 682	int ret;
 683
 684	/*
 685	 * Do not try to power off the domain in the following situations:
 686	 * (1) The domain is already in the "power off" state.
 687	 * (2) System suspend is in progress.
 688	 */
 689	if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
 690		return 0;
 691
 692	/*
 693	 * Abort power off for the PM domain in the following situations:
 694	 * (1) The domain is configured as always on.
 695	 * (2) When the domain has a subdomain being powered on.
 696	 */
 697	if (genpd_is_always_on(genpd) ||
 698			genpd_is_rpm_always_on(genpd) ||
 699			atomic_read(&genpd->sd_count) > 0)
 700		return -EBUSY;
 701
 702	/*
 703	 * The children must be in their deepest (powered-off) states to allow
 704	 * the parent to be powered off. Note that, there's no need for
 705	 * additional locking, as powering on a child, requires the parent's
 706	 * lock to be acquired first.
 707	 */
 708	list_for_each_entry(link, &genpd->parent_links, parent_node) {
 709		struct generic_pm_domain *child = link->child;
 710		if (child->state_idx < child->state_count - 1)
 711			return -EBUSY;
 712	}
 713
 714	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 715		/*
 716		 * Do not allow PM domain to be powered off, when an IRQ safe
 717		 * device is part of a non-IRQ safe domain.
 718		 */
 719		if (!pm_runtime_suspended(pdd->dev) ||
 720			irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
 721			not_suspended++;
 722	}
 723
 724	if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
 725		return -EBUSY;
 726
 727	if (genpd->gov && genpd->gov->power_down_ok) {
 728		if (!genpd->gov->power_down_ok(&genpd->domain))
 729			return -EAGAIN;
 730	}
 731
 732	/* Default to shallowest state. */
 733	if (!genpd->gov)
 734		genpd->state_idx = 0;
 735
 736	/* Don't power off, if a child domain is waiting to power on. */
 737	if (atomic_read(&genpd->sd_count) > 0)
 738		return -EBUSY;
 739
 740	ret = _genpd_power_off(genpd, true);
 741	if (ret) {
 742		genpd->states[genpd->state_idx].rejected++;
 743		return ret;
 744	}
 745
 746	genpd->status = GENPD_STATE_OFF;
 747	genpd_update_accounting(genpd);
 748	genpd->states[genpd->state_idx].usage++;
 749
 750	list_for_each_entry(link, &genpd->child_links, child_node) {
 751		genpd_sd_counter_dec(link->parent);
 752		genpd_lock_nested(link->parent, depth + 1);
 753		genpd_power_off(link->parent, false, depth + 1);
 754		genpd_unlock(link->parent);
 755	}
 756
 757	return 0;
 758}
 759
 760/**
 761 * genpd_power_on - Restore power to a given PM domain and its parents.
 762 * @genpd: PM domain to power up.
 763 * @depth: nesting count for lockdep.
 764 *
 765 * Restore power to @genpd and all of its parents so that it is possible to
 766 * resume a device belonging to it.
 767 */
 768static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
 769{
 770	struct gpd_link *link;
 771	int ret = 0;
 772
 773	if (genpd_status_on(genpd))
 774		return 0;
 775
 776	/*
 777	 * The list is guaranteed not to change while the loop below is being
 778	 * executed, unless one of the parents' .power_on() callbacks fiddles
 779	 * with it.
 780	 */
 781	list_for_each_entry(link, &genpd->child_links, child_node) {
 782		struct generic_pm_domain *parent = link->parent;
 783
 784		genpd_sd_counter_inc(parent);
 785
 786		genpd_lock_nested(parent, depth + 1);
 787		ret = genpd_power_on(parent, depth + 1);
 788		genpd_unlock(parent);
 789
 790		if (ret) {
 791			genpd_sd_counter_dec(parent);
 792			goto err;
 793		}
 794	}
 795
 796	ret = _genpd_power_on(genpd, true);
 797	if (ret)
 798		goto err;
 799
 800	genpd->status = GENPD_STATE_ON;
 801	genpd_update_accounting(genpd);
 802
 803	return 0;
 804
 805 err:
 806	list_for_each_entry_continue_reverse(link,
 807					&genpd->child_links,
 808					child_node) {
 809		genpd_sd_counter_dec(link->parent);
 810		genpd_lock_nested(link->parent, depth + 1);
 811		genpd_power_off(link->parent, false, depth + 1);
 812		genpd_unlock(link->parent);
 813	}
 814
 815	return ret;
 816}
 817
 818static int genpd_dev_pm_start(struct device *dev)
 819{
 820	struct generic_pm_domain *genpd = dev_to_genpd(dev);
 821
 822	return genpd_start_dev(genpd, dev);
 823}
 824
 825static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 826				     unsigned long val, void *ptr)
 827{
 828	struct generic_pm_domain_data *gpd_data;
 829	struct device *dev;
 830
 831	gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
 832	dev = gpd_data->base.dev;
 833
 834	for (;;) {
 835		struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
 836		struct pm_domain_data *pdd;
 837		struct gpd_timing_data *td;
 838
 839		spin_lock_irq(&dev->power.lock);
 840
 841		pdd = dev->power.subsys_data ?
 842				dev->power.subsys_data->domain_data : NULL;
 843		if (pdd) {
 844			td = to_gpd_data(pdd)->td;
 845			if (td) {
 846				td->constraint_changed = true;
 847				genpd = dev_to_genpd(dev);
 848			}
 849		}
 850
 851		spin_unlock_irq(&dev->power.lock);
 852
 853		if (!IS_ERR(genpd)) {
 854			genpd_lock(genpd);
 855			genpd->gd->max_off_time_changed = true;
 856			genpd_unlock(genpd);
 857		}
 858
 859		dev = dev->parent;
 860		if (!dev || dev->power.ignore_children)
 861			break;
 862	}
 863
 864	return NOTIFY_DONE;
 865}
 866
 867/**
 868 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 869 * @work: Work structure used for scheduling the execution of this function.
 870 */
 871static void genpd_power_off_work_fn(struct work_struct *work)
 872{
 873	struct generic_pm_domain *genpd;
 874
 875	genpd = container_of(work, struct generic_pm_domain, power_off_work);
 876
 877	genpd_lock(genpd);
 878	genpd_power_off(genpd, false, 0);
 879	genpd_unlock(genpd);
 880}
 881
 882/**
 883 * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
 884 * @dev: Device to handle.
 885 */
 886static int __genpd_runtime_suspend(struct device *dev)
 887{
 888	int (*cb)(struct device *__dev);
 889
 890	if (dev->type && dev->type->pm)
 891		cb = dev->type->pm->runtime_suspend;
 892	else if (dev->class && dev->class->pm)
 893		cb = dev->class->pm->runtime_suspend;
 894	else if (dev->bus && dev->bus->pm)
 895		cb = dev->bus->pm->runtime_suspend;
 896	else
 897		cb = NULL;
 898
 899	if (!cb && dev->driver && dev->driver->pm)
 900		cb = dev->driver->pm->runtime_suspend;
 901
 902	return cb ? cb(dev) : 0;
 903}
 904
 905/**
 906 * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
 907 * @dev: Device to handle.
 908 */
 909static int __genpd_runtime_resume(struct device *dev)
 910{
 911	int (*cb)(struct device *__dev);
 912
 913	if (dev->type && dev->type->pm)
 914		cb = dev->type->pm->runtime_resume;
 915	else if (dev->class && dev->class->pm)
 916		cb = dev->class->pm->runtime_resume;
 917	else if (dev->bus && dev->bus->pm)
 918		cb = dev->bus->pm->runtime_resume;
 919	else
 920		cb = NULL;
 921
 922	if (!cb && dev->driver && dev->driver->pm)
 923		cb = dev->driver->pm->runtime_resume;
 924
 925	return cb ? cb(dev) : 0;
 926}
 927
 928/**
 929 * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 930 * @dev: Device to suspend.
 931 *
 932 * Carry out a runtime suspend of a device under the assumption that its
 933 * pm_domain field points to the domain member of an object of type
 934 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 935 */
 936static int genpd_runtime_suspend(struct device *dev)
 937{
 938	struct generic_pm_domain *genpd;
 939	bool (*suspend_ok)(struct device *__dev);
 940	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
 941	struct gpd_timing_data *td = gpd_data->td;
 942	bool runtime_pm = pm_runtime_enabled(dev);
 943	ktime_t time_start = 0;
 944	s64 elapsed_ns;
 945	int ret;
 946
 947	dev_dbg(dev, "%s()\n", __func__);
 948
 949	genpd = dev_to_genpd(dev);
 950	if (IS_ERR(genpd))
 951		return -EINVAL;
 952
 953	/*
 954	 * A runtime PM centric subsystem/driver may re-use the runtime PM
 955	 * callbacks for other purposes than runtime PM. In those scenarios
 956	 * runtime PM is disabled. Under these circumstances, we shall skip
 957	 * validating/measuring the PM QoS latency.
 958	 */
 959	suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
 960	if (runtime_pm && suspend_ok && !suspend_ok(dev))
 961		return -EBUSY;
 962
 963	/* Measure suspend latency. */
 964	if (td && runtime_pm)
 965		time_start = ktime_get();
 966
 967	ret = __genpd_runtime_suspend(dev);
 968	if (ret)
 969		return ret;
 970
 971	ret = genpd_stop_dev(genpd, dev);
 972	if (ret) {
 973		__genpd_runtime_resume(dev);
 974		return ret;
 975	}
 976
 977	/* Update suspend latency value if the measured time exceeds it. */
 978	if (td && runtime_pm) {
 979		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 980		if (elapsed_ns > td->suspend_latency_ns) {
 981			td->suspend_latency_ns = elapsed_ns;
 982			dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
 983				elapsed_ns);
 984			genpd->gd->max_off_time_changed = true;
 985			td->constraint_changed = true;
 986		}
 987	}
 988
 989	/*
 990	 * If power.irq_safe is set, this routine may be run with
 991	 * IRQs disabled, so suspend only if the PM domain also is irq_safe.
 992	 */
 993	if (irq_safe_dev_in_sleep_domain(dev, genpd))
 994		return 0;
 995
 996	genpd_lock(genpd);
 997	genpd_power_off(genpd, true, 0);
 998	gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
 999	genpd_unlock(genpd);
1000
1001	return 0;
1002}
1003
1004/**
1005 * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
1006 * @dev: Device to resume.
1007 *
1008 * Carry out a runtime resume of a device under the assumption that its
1009 * pm_domain field points to the domain member of an object of type
1010 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
1011 */
1012static int genpd_runtime_resume(struct device *dev)
1013{
1014	struct generic_pm_domain *genpd;
1015	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
1016	struct gpd_timing_data *td = gpd_data->td;
1017	bool timed = td && pm_runtime_enabled(dev);
1018	ktime_t time_start = 0;
1019	s64 elapsed_ns;
1020	int ret;
1021
1022	dev_dbg(dev, "%s()\n", __func__);
1023
1024	genpd = dev_to_genpd(dev);
1025	if (IS_ERR(genpd))
1026		return -EINVAL;
1027
1028	/*
1029	 * As we don't power off a non IRQ safe domain, which holds
1030	 * an IRQ safe device, we don't need to restore power to it.
1031	 */
1032	if (irq_safe_dev_in_sleep_domain(dev, genpd))
1033		goto out;
1034
1035	genpd_lock(genpd);
1036	genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
1037	ret = genpd_power_on(genpd, 0);
1038	genpd_unlock(genpd);
1039
1040	if (ret)
1041		return ret;
1042
1043 out:
1044	/* Measure resume latency. */
1045	if (timed)
1046		time_start = ktime_get();
1047
1048	ret = genpd_start_dev(genpd, dev);
1049	if (ret)
1050		goto err_poweroff;
1051
1052	ret = __genpd_runtime_resume(dev);
1053	if (ret)
1054		goto err_stop;
1055
1056	/* Update resume latency value if the measured time exceeds it. */
1057	if (timed) {
1058		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
1059		if (elapsed_ns > td->resume_latency_ns) {
1060			td->resume_latency_ns = elapsed_ns;
1061			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
1062				elapsed_ns);
1063			genpd->gd->max_off_time_changed = true;
1064			td->constraint_changed = true;
1065		}
1066	}
1067
1068	return 0;
1069
1070err_stop:
1071	genpd_stop_dev(genpd, dev);
1072err_poweroff:
1073	if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
1074		genpd_lock(genpd);
1075		genpd_power_off(genpd, true, 0);
1076		gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
1077		genpd_unlock(genpd);
1078	}
1079
1080	return ret;
1081}
1082
1083static bool pd_ignore_unused;
1084static int __init pd_ignore_unused_setup(char *__unused)
1085{
1086	pd_ignore_unused = true;
1087	return 1;
1088}
1089__setup("pd_ignore_unused", pd_ignore_unused_setup);
1090
1091/**
1092 * genpd_power_off_unused - Power off all PM domains with no devices in use.
1093 */
1094static int __init genpd_power_off_unused(void)
1095{
1096	struct generic_pm_domain *genpd;
1097
1098	if (pd_ignore_unused) {
1099		pr_warn("genpd: Not disabling unused power domains\n");
1100		return 0;
1101	}
1102
 
1103	mutex_lock(&gpd_list_lock);
1104
1105	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
1106		genpd_queue_power_off_work(genpd);
1107
1108	mutex_unlock(&gpd_list_lock);
1109
1110	return 0;
1111}
1112late_initcall_sync(genpd_power_off_unused);
1113
1114#ifdef CONFIG_PM_SLEEP
1115
1116/**
1117 * genpd_sync_power_off - Synchronously power off a PM domain and its parents.
1118 * @genpd: PM domain to power off, if possible.
1119 * @use_lock: use the lock.
1120 * @depth: nesting count for lockdep.
1121 *
1122 * Check if the given PM domain can be powered off (during system suspend or
1123 * hibernation) and do that if so.  Also, in that case propagate to its parents.
1124 *
1125 * This function is only called in "noirq" and "syscore" stages of system power
1126 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1127 * these cases the lock must be held.
1128 */
1129static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
1130				 unsigned int depth)
1131{
1132	struct gpd_link *link;
1133
1134	if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
1135		return;
1136
1137	if (genpd->suspended_count != genpd->device_count
1138	    || atomic_read(&genpd->sd_count) > 0)
1139		return;
1140
1141	/* Check that the children are in their deepest (powered-off) state. */
1142	list_for_each_entry(link, &genpd->parent_links, parent_node) {
1143		struct generic_pm_domain *child = link->child;
1144		if (child->state_idx < child->state_count - 1)
1145			return;
1146	}
1147
1148	/* Choose the deepest state when suspending */
1149	genpd->state_idx = genpd->state_count - 1;
1150	if (_genpd_power_off(genpd, false))
 
1151		return;
 
 
 
1152
1153	genpd->status = GENPD_STATE_OFF;
1154
1155	list_for_each_entry(link, &genpd->child_links, child_node) {
1156		genpd_sd_counter_dec(link->parent);
1157
1158		if (use_lock)
1159			genpd_lock_nested(link->parent, depth + 1);
1160
1161		genpd_sync_power_off(link->parent, use_lock, depth + 1);
1162
1163		if (use_lock)
1164			genpd_unlock(link->parent);
1165	}
1166}
1167
1168/**
1169 * genpd_sync_power_on - Synchronously power on a PM domain and its parents.
1170 * @genpd: PM domain to power on.
1171 * @use_lock: use the lock.
1172 * @depth: nesting count for lockdep.
1173 *
1174 * This function is only called in "noirq" and "syscore" stages of system power
1175 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1176 * these cases the lock must be held.
1177 */
1178static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
1179				unsigned int depth)
1180{
1181	struct gpd_link *link;
1182
1183	if (genpd_status_on(genpd))
1184		return;
1185
1186	list_for_each_entry(link, &genpd->child_links, child_node) {
1187		genpd_sd_counter_inc(link->parent);
1188
1189		if (use_lock)
1190			genpd_lock_nested(link->parent, depth + 1);
1191
1192		genpd_sync_power_on(link->parent, use_lock, depth + 1);
1193
1194		if (use_lock)
1195			genpd_unlock(link->parent);
1196	}
1197
1198	_genpd_power_on(genpd, false);
1199	genpd->status = GENPD_STATE_ON;
1200}
1201
1202/**
1203 * genpd_prepare - Start power transition of a device in a PM domain.
1204 * @dev: Device to start the transition of.
1205 *
1206 * Start a power transition of a device (during a system-wide power transition)
1207 * under the assumption that its pm_domain field points to the domain member of
1208 * an object of type struct generic_pm_domain representing a PM domain
1209 * consisting of I/O devices.
1210 */
1211static int genpd_prepare(struct device *dev)
1212{
1213	struct generic_pm_domain *genpd;
1214	int ret;
1215
1216	dev_dbg(dev, "%s()\n", __func__);
1217
1218	genpd = dev_to_genpd(dev);
1219	if (IS_ERR(genpd))
1220		return -EINVAL;
1221
1222	genpd_lock(genpd);
1223
1224	if (genpd->prepared_count++ == 0)
1225		genpd->suspended_count = 0;
1226
1227	genpd_unlock(genpd);
1228
1229	ret = pm_generic_prepare(dev);
1230	if (ret < 0) {
1231		genpd_lock(genpd);
1232
1233		genpd->prepared_count--;
1234
1235		genpd_unlock(genpd);
1236	}
1237
1238	/* Never return 1, as genpd don't cope with the direct_complete path. */
1239	return ret >= 0 ? 0 : ret;
1240}
1241
1242/**
1243 * genpd_finish_suspend - Completion of suspend or hibernation of device in an
1244 *   I/O pm domain.
1245 * @dev: Device to suspend.
1246 * @suspend_noirq: Generic suspend_noirq callback.
1247 * @resume_noirq: Generic resume_noirq callback.
1248 *
1249 * Stop the device and remove power from the domain if all devices in it have
1250 * been stopped.
1251 */
1252static int genpd_finish_suspend(struct device *dev,
1253				int (*suspend_noirq)(struct device *dev),
1254				int (*resume_noirq)(struct device *dev))
1255{
1256	struct generic_pm_domain *genpd;
1257	int ret = 0;
1258
1259	genpd = dev_to_genpd(dev);
1260	if (IS_ERR(genpd))
1261		return -EINVAL;
1262
1263	ret = suspend_noirq(dev);
1264	if (ret)
1265		return ret;
1266
1267	if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1268		return 0;
1269
1270	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1271	    !pm_runtime_status_suspended(dev)) {
1272		ret = genpd_stop_dev(genpd, dev);
1273		if (ret) {
1274			resume_noirq(dev);
1275			return ret;
1276		}
1277	}
1278
1279	genpd_lock(genpd);
1280	genpd->suspended_count++;
1281	genpd_sync_power_off(genpd, true, 0);
1282	genpd_unlock(genpd);
1283
1284	return 0;
1285}
1286
1287/**
1288 * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1289 * @dev: Device to suspend.
1290 *
1291 * Stop the device and remove power from the domain if all devices in it have
1292 * been stopped.
1293 */
1294static int genpd_suspend_noirq(struct device *dev)
1295{
1296	dev_dbg(dev, "%s()\n", __func__);
1297
1298	return genpd_finish_suspend(dev,
1299				    pm_generic_suspend_noirq,
1300				    pm_generic_resume_noirq);
1301}
1302
1303/**
1304 * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
1305 * @dev: Device to resume.
1306 * @resume_noirq: Generic resume_noirq callback.
1307 *
1308 * Restore power to the device's PM domain, if necessary, and start the device.
1309 */
1310static int genpd_finish_resume(struct device *dev,
1311			       int (*resume_noirq)(struct device *dev))
1312{
1313	struct generic_pm_domain *genpd;
1314	int ret;
1315
1316	dev_dbg(dev, "%s()\n", __func__);
1317
1318	genpd = dev_to_genpd(dev);
1319	if (IS_ERR(genpd))
1320		return -EINVAL;
1321
1322	if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1323		return resume_noirq(dev);
1324
1325	genpd_lock(genpd);
1326	genpd_sync_power_on(genpd, true, 0);
1327	genpd->suspended_count--;
1328	genpd_unlock(genpd);
1329
1330	if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1331	    !pm_runtime_status_suspended(dev)) {
1332		ret = genpd_start_dev(genpd, dev);
1333		if (ret)
1334			return ret;
1335	}
1336
1337	return pm_generic_resume_noirq(dev);
1338}
1339
1340/**
1341 * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1342 * @dev: Device to resume.
1343 *
1344 * Restore power to the device's PM domain, if necessary, and start the device.
1345 */
1346static int genpd_resume_noirq(struct device *dev)
1347{
1348	dev_dbg(dev, "%s()\n", __func__);
1349
1350	return genpd_finish_resume(dev, pm_generic_resume_noirq);
1351}
1352
1353/**
1354 * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1355 * @dev: Device to freeze.
1356 *
1357 * Carry out a late freeze of a device under the assumption that its
1358 * pm_domain field points to the domain member of an object of type
1359 * struct generic_pm_domain representing a power domain consisting of I/O
1360 * devices.
1361 */
1362static int genpd_freeze_noirq(struct device *dev)
1363{
1364	dev_dbg(dev, "%s()\n", __func__);
1365
1366	return genpd_finish_suspend(dev,
1367				    pm_generic_freeze_noirq,
1368				    pm_generic_thaw_noirq);
1369}
1370
1371/**
1372 * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1373 * @dev: Device to thaw.
1374 *
1375 * Start the device, unless power has been removed from the domain already
1376 * before the system transition.
1377 */
1378static int genpd_thaw_noirq(struct device *dev)
1379{
1380	dev_dbg(dev, "%s()\n", __func__);
1381
1382	return genpd_finish_resume(dev, pm_generic_thaw_noirq);
1383}
1384
1385/**
1386 * genpd_poweroff_noirq - Completion of hibernation of device in an
1387 *   I/O PM domain.
1388 * @dev: Device to poweroff.
1389 *
1390 * Stop the device and remove power from the domain if all devices in it have
1391 * been stopped.
1392 */
1393static int genpd_poweroff_noirq(struct device *dev)
1394{
1395	dev_dbg(dev, "%s()\n", __func__);
1396
1397	return genpd_finish_suspend(dev,
1398				    pm_generic_poweroff_noirq,
1399				    pm_generic_restore_noirq);
1400}
1401
1402/**
1403 * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1404 * @dev: Device to resume.
1405 *
1406 * Make sure the domain will be in the same power state as before the
1407 * hibernation the system is resuming from and start the device if necessary.
1408 */
1409static int genpd_restore_noirq(struct device *dev)
1410{
1411	dev_dbg(dev, "%s()\n", __func__);
1412
1413	return genpd_finish_resume(dev, pm_generic_restore_noirq);
1414}
1415
1416/**
1417 * genpd_complete - Complete power transition of a device in a power domain.
1418 * @dev: Device to complete the transition of.
1419 *
1420 * Complete a power transition of a device (during a system-wide power
1421 * transition) under the assumption that its pm_domain field points to the
1422 * domain member of an object of type struct generic_pm_domain representing
1423 * a power domain consisting of I/O devices.
1424 */
1425static void genpd_complete(struct device *dev)
1426{
1427	struct generic_pm_domain *genpd;
1428
1429	dev_dbg(dev, "%s()\n", __func__);
1430
1431	genpd = dev_to_genpd(dev);
1432	if (IS_ERR(genpd))
1433		return;
1434
1435	pm_generic_complete(dev);
1436
1437	genpd_lock(genpd);
1438
1439	genpd->prepared_count--;
1440	if (!genpd->prepared_count)
1441		genpd_queue_power_off_work(genpd);
1442
1443	genpd_unlock(genpd);
1444}
1445
1446static void genpd_switch_state(struct device *dev, bool suspend)
1447{
1448	struct generic_pm_domain *genpd;
1449	bool use_lock;
1450
1451	genpd = dev_to_genpd_safe(dev);
1452	if (!genpd)
1453		return;
1454
1455	use_lock = genpd_is_irq_safe(genpd);
1456
1457	if (use_lock)
1458		genpd_lock(genpd);
1459
1460	if (suspend) {
1461		genpd->suspended_count++;
1462		genpd_sync_power_off(genpd, use_lock, 0);
1463	} else {
1464		genpd_sync_power_on(genpd, use_lock, 0);
1465		genpd->suspended_count--;
1466	}
1467
1468	if (use_lock)
1469		genpd_unlock(genpd);
1470}
1471
1472/**
1473 * dev_pm_genpd_suspend - Synchronously try to suspend the genpd for @dev
1474 * @dev: The device that is attached to the genpd, that can be suspended.
1475 *
1476 * This routine should typically be called for a device that needs to be
1477 * suspended during the syscore suspend phase. It may also be called during
1478 * suspend-to-idle to suspend a corresponding CPU device that is attached to a
1479 * genpd.
1480 */
1481void dev_pm_genpd_suspend(struct device *dev)
1482{
1483	genpd_switch_state(dev, true);
1484}
1485EXPORT_SYMBOL_GPL(dev_pm_genpd_suspend);
1486
1487/**
1488 * dev_pm_genpd_resume - Synchronously try to resume the genpd for @dev
1489 * @dev: The device that is attached to the genpd, which needs to be resumed.
1490 *
1491 * This routine should typically be called for a device that needs to be resumed
1492 * during the syscore resume phase. It may also be called during suspend-to-idle
1493 * to resume a corresponding CPU device that is attached to a genpd.
1494 */
1495void dev_pm_genpd_resume(struct device *dev)
1496{
1497	genpd_switch_state(dev, false);
1498}
1499EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
1500
1501#else /* !CONFIG_PM_SLEEP */
1502
1503#define genpd_prepare		NULL
1504#define genpd_suspend_noirq	NULL
1505#define genpd_resume_noirq	NULL
1506#define genpd_freeze_noirq	NULL
1507#define genpd_thaw_noirq	NULL
1508#define genpd_poweroff_noirq	NULL
1509#define genpd_restore_noirq	NULL
1510#define genpd_complete		NULL
1511
1512#endif /* CONFIG_PM_SLEEP */
1513
1514static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1515							   bool has_governor)
1516{
1517	struct generic_pm_domain_data *gpd_data;
1518	struct gpd_timing_data *td;
1519	int ret;
1520
1521	ret = dev_pm_get_subsys_data(dev);
1522	if (ret)
1523		return ERR_PTR(ret);
1524
1525	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1526	if (!gpd_data) {
1527		ret = -ENOMEM;
1528		goto err_put;
1529	}
1530
1531	gpd_data->base.dev = dev;
1532	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1533
1534	/* Allocate data used by a governor. */
1535	if (has_governor) {
1536		td = kzalloc(sizeof(*td), GFP_KERNEL);
1537		if (!td) {
1538			ret = -ENOMEM;
1539			goto err_free;
1540		}
1541
1542		td->constraint_changed = true;
1543		td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
1544		td->next_wakeup = KTIME_MAX;
1545		gpd_data->td = td;
1546	}
1547
1548	spin_lock_irq(&dev->power.lock);
1549
1550	if (dev->power.subsys_data->domain_data)
1551		ret = -EINVAL;
1552	else
1553		dev->power.subsys_data->domain_data = &gpd_data->base;
1554
1555	spin_unlock_irq(&dev->power.lock);
1556
1557	if (ret)
1558		goto err_free;
1559
1560	return gpd_data;
1561
1562 err_free:
1563	kfree(gpd_data->td);
1564	kfree(gpd_data);
1565 err_put:
1566	dev_pm_put_subsys_data(dev);
1567	return ERR_PTR(ret);
1568}
1569
1570static void genpd_free_dev_data(struct device *dev,
1571				struct generic_pm_domain_data *gpd_data)
1572{
1573	spin_lock_irq(&dev->power.lock);
1574
1575	dev->power.subsys_data->domain_data = NULL;
1576
1577	spin_unlock_irq(&dev->power.lock);
1578
 
1579	kfree(gpd_data->td);
1580	kfree(gpd_data);
1581	dev_pm_put_subsys_data(dev);
1582}
1583
1584static void genpd_update_cpumask(struct generic_pm_domain *genpd,
1585				 int cpu, bool set, unsigned int depth)
1586{
1587	struct gpd_link *link;
1588
1589	if (!genpd_is_cpu_domain(genpd))
1590		return;
1591
1592	list_for_each_entry(link, &genpd->child_links, child_node) {
1593		struct generic_pm_domain *parent = link->parent;
1594
1595		genpd_lock_nested(parent, depth + 1);
1596		genpd_update_cpumask(parent, cpu, set, depth + 1);
1597		genpd_unlock(parent);
1598	}
1599
1600	if (set)
1601		cpumask_set_cpu(cpu, genpd->cpus);
1602	else
1603		cpumask_clear_cpu(cpu, genpd->cpus);
1604}
1605
1606static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
1607{
1608	if (cpu >= 0)
1609		genpd_update_cpumask(genpd, cpu, true, 0);
1610}
1611
1612static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
1613{
1614	if (cpu >= 0)
1615		genpd_update_cpumask(genpd, cpu, false, 0);
1616}
1617
1618static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
1619{
1620	int cpu;
1621
1622	if (!genpd_is_cpu_domain(genpd))
1623		return -1;
1624
1625	for_each_possible_cpu(cpu) {
1626		if (get_cpu_device(cpu) == dev)
1627			return cpu;
1628	}
1629
1630	return -1;
1631}
1632
1633static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1634			    struct device *base_dev)
1635{
1636	struct genpd_governor_data *gd = genpd->gd;
1637	struct generic_pm_domain_data *gpd_data;
1638	int ret;
1639
1640	dev_dbg(dev, "%s()\n", __func__);
1641
1642	gpd_data = genpd_alloc_dev_data(dev, gd);
1643	if (IS_ERR(gpd_data))
1644		return PTR_ERR(gpd_data);
1645
1646	gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
1647
 
 
1648	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1649	if (ret)
1650		goto out;
1651
1652	genpd_lock(genpd);
1653
1654	genpd_set_cpumask(genpd, gpd_data->cpu);
1655	dev_pm_domain_set(dev, &genpd->domain);
1656
1657	genpd->device_count++;
1658	if (gd)
1659		gd->max_off_time_changed = true;
1660
1661	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1662
1663	genpd_unlock(genpd);
 
1664 out:
1665	if (ret)
1666		genpd_free_dev_data(dev, gpd_data);
1667	else
1668		dev_pm_qos_add_notifier(dev, &gpd_data->nb,
1669					DEV_PM_QOS_RESUME_LATENCY);
1670
1671	return ret;
1672}
1673
1674/**
1675 * pm_genpd_add_device - Add a device to an I/O PM domain.
1676 * @genpd: PM domain to add the device to.
1677 * @dev: Device to be added.
1678 */
1679int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
1680{
1681	int ret;
1682
1683	if (!genpd || !dev)
1684		return -EINVAL;
1685
1686	mutex_lock(&gpd_list_lock);
1687	ret = genpd_add_device(genpd, dev, dev);
1688	mutex_unlock(&gpd_list_lock);
1689
1690	return ret;
1691}
1692EXPORT_SYMBOL_GPL(pm_genpd_add_device);
1693
1694static int genpd_remove_device(struct generic_pm_domain *genpd,
1695			       struct device *dev)
1696{
1697	struct generic_pm_domain_data *gpd_data;
1698	struct pm_domain_data *pdd;
1699	int ret = 0;
1700
1701	dev_dbg(dev, "%s()\n", __func__);
1702
1703	pdd = dev->power.subsys_data->domain_data;
1704	gpd_data = to_gpd_data(pdd);
1705	dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
1706				   DEV_PM_QOS_RESUME_LATENCY);
1707
1708	genpd_lock(genpd);
1709
1710	if (genpd->prepared_count > 0) {
1711		ret = -EAGAIN;
1712		goto out;
1713	}
1714
1715	genpd->device_count--;
1716	if (genpd->gd)
1717		genpd->gd->max_off_time_changed = true;
1718
1719	genpd_clear_cpumask(genpd, gpd_data->cpu);
1720	dev_pm_domain_set(dev, NULL);
1721
1722	list_del_init(&pdd->list_node);
1723
1724	genpd_unlock(genpd);
1725
 
 
1726	if (genpd->detach_dev)
1727		genpd->detach_dev(genpd, dev);
1728
1729	genpd_free_dev_data(dev, gpd_data);
1730
1731	return 0;
1732
1733 out:
1734	genpd_unlock(genpd);
1735	dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
1736
1737	return ret;
1738}
1739
1740/**
1741 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1742 * @dev: Device to be removed.
1743 */
1744int pm_genpd_remove_device(struct device *dev)
1745{
1746	struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
1747
1748	if (!genpd)
1749		return -EINVAL;
1750
1751	return genpd_remove_device(genpd, dev);
1752}
1753EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1754
1755/**
1756 * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev
1757 *
1758 * @dev: Device that should be associated with the notifier
1759 * @nb: The notifier block to register
1760 *
1761 * Users may call this function to add a genpd power on/off notifier for an
1762 * attached @dev. Only one notifier per device is allowed. The notifier is
1763 * sent when genpd is powering on/off the PM domain.
1764 *
1765 * It is assumed that the user guarantee that the genpd wouldn't be detached
1766 * while this routine is getting called.
1767 *
1768 * Returns 0 on success and negative error values on failures.
1769 */
1770int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb)
1771{
1772	struct generic_pm_domain *genpd;
1773	struct generic_pm_domain_data *gpd_data;
1774	int ret;
1775
1776	genpd = dev_to_genpd_safe(dev);
1777	if (!genpd)
1778		return -ENODEV;
1779
1780	if (WARN_ON(!dev->power.subsys_data ||
1781		     !dev->power.subsys_data->domain_data))
1782		return -EINVAL;
1783
1784	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1785	if (gpd_data->power_nb)
1786		return -EEXIST;
1787
1788	genpd_lock(genpd);
1789	ret = raw_notifier_chain_register(&genpd->power_notifiers, nb);
1790	genpd_unlock(genpd);
1791
1792	if (ret) {
1793		dev_warn(dev, "failed to add notifier for PM domain %s\n",
1794			 genpd->name);
1795		return ret;
1796	}
1797
1798	gpd_data->power_nb = nb;
1799	return 0;
1800}
1801EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier);
1802
1803/**
1804 * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev
1805 *
1806 * @dev: Device that is associated with the notifier
1807 *
1808 * Users may call this function to remove a genpd power on/off notifier for an
1809 * attached @dev.
1810 *
1811 * It is assumed that the user guarantee that the genpd wouldn't be detached
1812 * while this routine is getting called.
1813 *
1814 * Returns 0 on success and negative error values on failures.
1815 */
1816int dev_pm_genpd_remove_notifier(struct device *dev)
1817{
1818	struct generic_pm_domain *genpd;
1819	struct generic_pm_domain_data *gpd_data;
1820	int ret;
1821
1822	genpd = dev_to_genpd_safe(dev);
1823	if (!genpd)
1824		return -ENODEV;
1825
1826	if (WARN_ON(!dev->power.subsys_data ||
1827		     !dev->power.subsys_data->domain_data))
1828		return -EINVAL;
1829
1830	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1831	if (!gpd_data->power_nb)
1832		return -ENODEV;
1833
1834	genpd_lock(genpd);
1835	ret = raw_notifier_chain_unregister(&genpd->power_notifiers,
1836					    gpd_data->power_nb);
1837	genpd_unlock(genpd);
1838
1839	if (ret) {
1840		dev_warn(dev, "failed to remove notifier for PM domain %s\n",
1841			 genpd->name);
1842		return ret;
1843	}
1844
1845	gpd_data->power_nb = NULL;
1846	return 0;
1847}
1848EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier);
1849
1850static int genpd_add_subdomain(struct generic_pm_domain *genpd,
1851			       struct generic_pm_domain *subdomain)
1852{
1853	struct gpd_link *link, *itr;
1854	int ret = 0;
1855
1856	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1857	    || genpd == subdomain)
1858		return -EINVAL;
1859
1860	/*
1861	 * If the domain can be powered on/off in an IRQ safe
1862	 * context, ensure that the subdomain can also be
1863	 * powered on/off in that context.
1864	 */
1865	if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
1866		WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
1867				genpd->name, subdomain->name);
1868		return -EINVAL;
1869	}
1870
1871	link = kzalloc(sizeof(*link), GFP_KERNEL);
1872	if (!link)
1873		return -ENOMEM;
1874
1875	genpd_lock(subdomain);
1876	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1877
1878	if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
1879		ret = -EINVAL;
1880		goto out;
1881	}
1882
1883	list_for_each_entry(itr, &genpd->parent_links, parent_node) {
1884		if (itr->child == subdomain && itr->parent == genpd) {
1885			ret = -EINVAL;
1886			goto out;
1887		}
1888	}
1889
1890	link->parent = genpd;
1891	list_add_tail(&link->parent_node, &genpd->parent_links);
1892	link->child = subdomain;
1893	list_add_tail(&link->child_node, &subdomain->child_links);
1894	if (genpd_status_on(subdomain))
1895		genpd_sd_counter_inc(genpd);
1896
1897 out:
1898	genpd_unlock(genpd);
1899	genpd_unlock(subdomain);
1900	if (ret)
1901		kfree(link);
1902	return ret;
1903}
1904
1905/**
1906 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1907 * @genpd: Leader PM domain to add the subdomain to.
1908 * @subdomain: Subdomain to be added.
1909 */
1910int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1911			   struct generic_pm_domain *subdomain)
1912{
1913	int ret;
1914
1915	mutex_lock(&gpd_list_lock);
1916	ret = genpd_add_subdomain(genpd, subdomain);
1917	mutex_unlock(&gpd_list_lock);
1918
1919	return ret;
1920}
1921EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1922
1923/**
1924 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1925 * @genpd: Leader PM domain to remove the subdomain from.
1926 * @subdomain: Subdomain to be removed.
1927 */
1928int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1929			      struct generic_pm_domain *subdomain)
1930{
1931	struct gpd_link *l, *link;
1932	int ret = -EINVAL;
1933
1934	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1935		return -EINVAL;
1936
1937	genpd_lock(subdomain);
1938	genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1939
1940	if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {
1941		pr_warn("%s: unable to remove subdomain %s\n",
1942			genpd->name, subdomain->name);
1943		ret = -EBUSY;
1944		goto out;
1945	}
1946
1947	list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {
1948		if (link->child != subdomain)
1949			continue;
1950
1951		list_del(&link->parent_node);
1952		list_del(&link->child_node);
1953		kfree(link);
1954		if (genpd_status_on(subdomain))
1955			genpd_sd_counter_dec(genpd);
1956
1957		ret = 0;
1958		break;
1959	}
1960
1961out:
1962	genpd_unlock(genpd);
1963	genpd_unlock(subdomain);
1964
1965	return ret;
1966}
1967EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1968
1969static void genpd_free_default_power_state(struct genpd_power_state *states,
1970					   unsigned int state_count)
1971{
1972	kfree(states);
1973}
1974
1975static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
1976{
1977	struct genpd_power_state *state;
1978
1979	state = kzalloc(sizeof(*state), GFP_KERNEL);
1980	if (!state)
1981		return -ENOMEM;
1982
1983	genpd->states = state;
1984	genpd->state_count = 1;
1985	genpd->free_states = genpd_free_default_power_state;
1986
1987	return 0;
1988}
1989
 
 
 
 
 
1990static int genpd_alloc_data(struct generic_pm_domain *genpd)
1991{
1992	struct genpd_governor_data *gd = NULL;
1993	int ret;
1994
1995	if (genpd_is_cpu_domain(genpd) &&
1996	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
1997		return -ENOMEM;
1998
1999	if (genpd->gov) {
2000		gd = kzalloc(sizeof(*gd), GFP_KERNEL);
2001		if (!gd) {
2002			ret = -ENOMEM;
2003			goto free;
2004		}
2005
2006		gd->max_off_time_ns = -1;
2007		gd->max_off_time_changed = true;
2008		gd->next_wakeup = KTIME_MAX;
2009		gd->next_hrtimer = KTIME_MAX;
2010	}
2011
2012	/* Use only one "off" state if there were no states declared */
2013	if (genpd->state_count == 0) {
2014		ret = genpd_set_default_power_state(genpd);
2015		if (ret)
2016			goto free;
2017	}
2018
2019	genpd->gd = gd;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2020	return 0;
2021
 
 
 
2022free:
2023	if (genpd_is_cpu_domain(genpd))
2024		free_cpumask_var(genpd->cpus);
2025	kfree(gd);
2026	return ret;
2027}
2028
2029static void genpd_free_data(struct generic_pm_domain *genpd)
2030{
 
 
 
2031	if (genpd_is_cpu_domain(genpd))
2032		free_cpumask_var(genpd->cpus);
2033	if (genpd->free_states)
2034		genpd->free_states(genpd->states, genpd->state_count);
2035	kfree(genpd->gd);
2036}
2037
2038static void genpd_lock_init(struct generic_pm_domain *genpd)
2039{
2040	if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
 
 
 
2041		spin_lock_init(&genpd->slock);
2042		genpd->lock_ops = &genpd_spin_ops;
2043	} else {
2044		mutex_init(&genpd->mlock);
2045		genpd->lock_ops = &genpd_mtx_ops;
2046	}
2047}
2048
2049/**
2050 * pm_genpd_init - Initialize a generic I/O PM domain object.
2051 * @genpd: PM domain object to initialize.
2052 * @gov: PM domain governor to associate with the domain (may be NULL).
2053 * @is_off: Initial value of the domain's power_is_off field.
2054 *
2055 * Returns 0 on successful initialization, else a negative error code.
2056 */
2057int pm_genpd_init(struct generic_pm_domain *genpd,
2058		  struct dev_power_governor *gov, bool is_off)
2059{
2060	int ret;
2061
2062	if (IS_ERR_OR_NULL(genpd))
2063		return -EINVAL;
2064
2065	INIT_LIST_HEAD(&genpd->parent_links);
2066	INIT_LIST_HEAD(&genpd->child_links);
2067	INIT_LIST_HEAD(&genpd->dev_list);
2068	RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers);
2069	genpd_lock_init(genpd);
2070	genpd->gov = gov;
2071	INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2072	atomic_set(&genpd->sd_count, 0);
2073	genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
2074	genpd->device_count = 0;
2075	genpd->provider = NULL;
 
2076	genpd->has_provider = false;
2077	genpd->accounting_time = ktime_get_mono_fast_ns();
2078	genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
2079	genpd->domain.ops.runtime_resume = genpd_runtime_resume;
2080	genpd->domain.ops.prepare = genpd_prepare;
2081	genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
2082	genpd->domain.ops.resume_noirq = genpd_resume_noirq;
2083	genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
2084	genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
2085	genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
2086	genpd->domain.ops.restore_noirq = genpd_restore_noirq;
2087	genpd->domain.ops.complete = genpd_complete;
2088	genpd->domain.start = genpd_dev_pm_start;
2089	genpd->domain.set_performance_state = genpd_dev_pm_set_performance_state;
2090
2091	if (genpd->flags & GENPD_FLAG_PM_CLK) {
2092		genpd->dev_ops.stop = pm_clk_suspend;
2093		genpd->dev_ops.start = pm_clk_resume;
2094	}
2095
2096	/* The always-on governor works better with the corresponding flag. */
2097	if (gov == &pm_domain_always_on_gov)
2098		genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
2099
2100	/* Always-on domains must be powered on at initialization. */
2101	if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
2102			!genpd_status_on(genpd)) {
2103		pr_err("always-on PM domain %s is not on\n", genpd->name);
2104		return -EINVAL;
2105	}
2106
2107	/* Multiple states but no governor doesn't make sense. */
2108	if (!gov && genpd->state_count > 1)
2109		pr_warn("%s: no governor for states\n", genpd->name);
2110
2111	ret = genpd_alloc_data(genpd);
2112	if (ret)
2113		return ret;
2114
2115	device_initialize(&genpd->dev);
2116	dev_set_name(&genpd->dev, "%s", genpd->name);
2117
2118	mutex_lock(&gpd_list_lock);
2119	list_add(&genpd->gpd_list_node, &gpd_list);
2120	mutex_unlock(&gpd_list_lock);
2121	genpd_debug_add(genpd);
2122
2123	return 0;
2124}
2125EXPORT_SYMBOL_GPL(pm_genpd_init);
2126
2127static int genpd_remove(struct generic_pm_domain *genpd)
2128{
2129	struct gpd_link *l, *link;
2130
2131	if (IS_ERR_OR_NULL(genpd))
2132		return -EINVAL;
2133
2134	genpd_lock(genpd);
2135
2136	if (genpd->has_provider) {
2137		genpd_unlock(genpd);
2138		pr_err("Provider present, unable to remove %s\n", genpd->name);
2139		return -EBUSY;
2140	}
2141
2142	if (!list_empty(&genpd->parent_links) || genpd->device_count) {
2143		genpd_unlock(genpd);
2144		pr_err("%s: unable to remove %s\n", __func__, genpd->name);
2145		return -EBUSY;
2146	}
2147
2148	list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {
2149		list_del(&link->parent_node);
2150		list_del(&link->child_node);
2151		kfree(link);
2152	}
2153
2154	list_del(&genpd->gpd_list_node);
2155	genpd_unlock(genpd);
2156	genpd_debug_remove(genpd);
2157	cancel_work_sync(&genpd->power_off_work);
2158	genpd_free_data(genpd);
2159
2160	pr_debug("%s: removed %s\n", __func__, genpd->name);
2161
2162	return 0;
2163}
2164
2165/**
2166 * pm_genpd_remove - Remove a generic I/O PM domain
2167 * @genpd: Pointer to PM domain that is to be removed.
2168 *
2169 * To remove the PM domain, this function:
2170 *  - Removes the PM domain as a subdomain to any parent domains,
2171 *    if it was added.
2172 *  - Removes the PM domain from the list of registered PM domains.
2173 *
2174 * The PM domain will only be removed, if the associated provider has
2175 * been removed, it is not a parent to any other PM domain and has no
2176 * devices associated with it.
2177 */
2178int pm_genpd_remove(struct generic_pm_domain *genpd)
2179{
2180	int ret;
2181
2182	mutex_lock(&gpd_list_lock);
2183	ret = genpd_remove(genpd);
2184	mutex_unlock(&gpd_list_lock);
2185
2186	return ret;
2187}
2188EXPORT_SYMBOL_GPL(pm_genpd_remove);
2189
2190#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
2191
2192/*
2193 * Device Tree based PM domain providers.
2194 *
2195 * The code below implements generic device tree based PM domain providers that
2196 * bind device tree nodes with generic PM domains registered in the system.
2197 *
2198 * Any driver that registers generic PM domains and needs to support binding of
2199 * devices to these domains is supposed to register a PM domain provider, which
2200 * maps a PM domain specifier retrieved from the device tree to a PM domain.
2201 *
2202 * Two simple mapping functions have been provided for convenience:
2203 *  - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
2204 *  - genpd_xlate_onecell() for mapping of multiple PM domains per node by
2205 *    index.
2206 */
2207
2208/**
2209 * struct of_genpd_provider - PM domain provider registration structure
2210 * @link: Entry in global list of PM domain providers
2211 * @node: Pointer to device tree node of PM domain provider
2212 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
2213 *         into a PM domain.
2214 * @data: context pointer to be passed into @xlate callback
2215 */
2216struct of_genpd_provider {
2217	struct list_head link;
2218	struct device_node *node;
2219	genpd_xlate_t xlate;
2220	void *data;
2221};
2222
2223/* List of registered PM domain providers. */
2224static LIST_HEAD(of_genpd_providers);
2225/* Mutex to protect the list above. */
2226static DEFINE_MUTEX(of_genpd_mutex);
2227
2228/**
2229 * genpd_xlate_simple() - Xlate function for direct node-domain mapping
2230 * @genpdspec: OF phandle args to map into a PM domain
2231 * @data: xlate function private data - pointer to struct generic_pm_domain
2232 *
2233 * This is a generic xlate function that can be used to model PM domains that
2234 * have their own device tree nodes. The private data of xlate function needs
2235 * to be a valid pointer to struct generic_pm_domain.
2236 */
2237static struct generic_pm_domain *genpd_xlate_simple(
2238					struct of_phandle_args *genpdspec,
2239					void *data)
2240{
2241	return data;
2242}
2243
2244/**
2245 * genpd_xlate_onecell() - Xlate function using a single index.
2246 * @genpdspec: OF phandle args to map into a PM domain
2247 * @data: xlate function private data - pointer to struct genpd_onecell_data
2248 *
2249 * This is a generic xlate function that can be used to model simple PM domain
2250 * controllers that have one device tree node and provide multiple PM domains.
2251 * A single cell is used as an index into an array of PM domains specified in
2252 * the genpd_onecell_data struct when registering the provider.
2253 */
2254static struct generic_pm_domain *genpd_xlate_onecell(
2255					struct of_phandle_args *genpdspec,
2256					void *data)
2257{
2258	struct genpd_onecell_data *genpd_data = data;
2259	unsigned int idx = genpdspec->args[0];
2260
2261	if (genpdspec->args_count != 1)
2262		return ERR_PTR(-EINVAL);
2263
2264	if (idx >= genpd_data->num_domains) {
2265		pr_err("%s: invalid domain index %u\n", __func__, idx);
2266		return ERR_PTR(-EINVAL);
2267	}
2268
2269	if (!genpd_data->domains[idx])
2270		return ERR_PTR(-ENOENT);
2271
2272	return genpd_data->domains[idx];
2273}
2274
2275/**
2276 * genpd_add_provider() - Register a PM domain provider for a node
2277 * @np: Device node pointer associated with the PM domain provider.
2278 * @xlate: Callback for decoding PM domain from phandle arguments.
2279 * @data: Context pointer for @xlate callback.
2280 */
2281static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
2282			      void *data)
2283{
2284	struct of_genpd_provider *cp;
2285
2286	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
2287	if (!cp)
2288		return -ENOMEM;
2289
2290	cp->node = of_node_get(np);
2291	cp->data = data;
2292	cp->xlate = xlate;
2293	fwnode_dev_initialized(&np->fwnode, true);
2294
2295	mutex_lock(&of_genpd_mutex);
2296	list_add(&cp->link, &of_genpd_providers);
2297	mutex_unlock(&of_genpd_mutex);
2298	pr_debug("Added domain provider from %pOF\n", np);
2299
2300	return 0;
2301}
2302
2303static bool genpd_present(const struct generic_pm_domain *genpd)
2304{
2305	bool ret = false;
2306	const struct generic_pm_domain *gpd;
2307
2308	mutex_lock(&gpd_list_lock);
2309	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2310		if (gpd == genpd) {
2311			ret = true;
2312			break;
2313		}
2314	}
2315	mutex_unlock(&gpd_list_lock);
2316
2317	return ret;
2318}
2319
2320/**
2321 * of_genpd_add_provider_simple() - Register a simple PM domain provider
2322 * @np: Device node pointer associated with the PM domain provider.
2323 * @genpd: Pointer to PM domain associated with the PM domain provider.
2324 */
2325int of_genpd_add_provider_simple(struct device_node *np,
2326				 struct generic_pm_domain *genpd)
2327{
2328	int ret;
2329
2330	if (!np || !genpd)
2331		return -EINVAL;
2332
2333	if (!genpd_present(genpd))
2334		return -EINVAL;
2335
2336	genpd->dev.of_node = np;
2337
2338	/* Parse genpd OPP table */
2339	if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2340		ret = dev_pm_opp_of_add_table(&genpd->dev);
2341		if (ret)
2342			return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
2343
2344		/*
2345		 * Save table for faster processing while setting performance
2346		 * state.
2347		 */
2348		genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2349		WARN_ON(IS_ERR(genpd->opp_table));
2350	}
2351
2352	ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
2353	if (ret) {
2354		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2355			dev_pm_opp_put_opp_table(genpd->opp_table);
2356			dev_pm_opp_of_remove_table(&genpd->dev);
2357		}
2358
2359		return ret;
2360	}
2361
2362	genpd->provider = &np->fwnode;
2363	genpd->has_provider = true;
2364
2365	return 0;
2366}
2367EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
2368
2369/**
2370 * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
2371 * @np: Device node pointer associated with the PM domain provider.
2372 * @data: Pointer to the data associated with the PM domain provider.
2373 */
2374int of_genpd_add_provider_onecell(struct device_node *np,
2375				  struct genpd_onecell_data *data)
2376{
2377	struct generic_pm_domain *genpd;
2378	unsigned int i;
2379	int ret = -EINVAL;
2380
2381	if (!np || !data)
2382		return -EINVAL;
2383
2384	if (!data->xlate)
2385		data->xlate = genpd_xlate_onecell;
2386
2387	for (i = 0; i < data->num_domains; i++) {
2388		genpd = data->domains[i];
2389
2390		if (!genpd)
2391			continue;
2392		if (!genpd_present(genpd))
2393			goto error;
2394
2395		genpd->dev.of_node = np;
2396
2397		/* Parse genpd OPP table */
2398		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2399			ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
2400			if (ret) {
2401				dev_err_probe(&genpd->dev, ret,
2402					      "Failed to add OPP table for index %d\n", i);
2403				goto error;
2404			}
2405
2406			/*
2407			 * Save table for faster processing while setting
2408			 * performance state.
2409			 */
2410			genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2411			WARN_ON(IS_ERR(genpd->opp_table));
2412		}
2413
2414		genpd->provider = &np->fwnode;
2415		genpd->has_provider = true;
2416	}
2417
2418	ret = genpd_add_provider(np, data->xlate, data);
2419	if (ret < 0)
2420		goto error;
2421
2422	return 0;
2423
2424error:
2425	while (i--) {
2426		genpd = data->domains[i];
2427
2428		if (!genpd)
2429			continue;
2430
2431		genpd->provider = NULL;
2432		genpd->has_provider = false;
2433
2434		if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
2435			dev_pm_opp_put_opp_table(genpd->opp_table);
2436			dev_pm_opp_of_remove_table(&genpd->dev);
2437		}
2438	}
2439
2440	return ret;
2441}
2442EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
2443
2444/**
2445 * of_genpd_del_provider() - Remove a previously registered PM domain provider
2446 * @np: Device node pointer associated with the PM domain provider
2447 */
2448void of_genpd_del_provider(struct device_node *np)
2449{
2450	struct of_genpd_provider *cp, *tmp;
2451	struct generic_pm_domain *gpd;
2452
2453	mutex_lock(&gpd_list_lock);
2454	mutex_lock(&of_genpd_mutex);
2455	list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
2456		if (cp->node == np) {
2457			/*
2458			 * For each PM domain associated with the
2459			 * provider, set the 'has_provider' to false
2460			 * so that the PM domain can be safely removed.
2461			 */
2462			list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2463				if (gpd->provider == &np->fwnode) {
2464					gpd->has_provider = false;
2465
2466					if (genpd_is_opp_table_fw(gpd) || !gpd->set_performance_state)
2467						continue;
2468
2469					dev_pm_opp_put_opp_table(gpd->opp_table);
2470					dev_pm_opp_of_remove_table(&gpd->dev);
2471				}
2472			}
2473
2474			fwnode_dev_initialized(&cp->node->fwnode, false);
2475			list_del(&cp->link);
2476			of_node_put(cp->node);
2477			kfree(cp);
2478			break;
2479		}
2480	}
2481	mutex_unlock(&of_genpd_mutex);
2482	mutex_unlock(&gpd_list_lock);
2483}
2484EXPORT_SYMBOL_GPL(of_genpd_del_provider);
2485
2486/**
2487 * genpd_get_from_provider() - Look-up PM domain
2488 * @genpdspec: OF phandle args to use for look-up
2489 *
2490 * Looks for a PM domain provider under the node specified by @genpdspec and if
2491 * found, uses xlate function of the provider to map phandle args to a PM
2492 * domain.
2493 *
2494 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
2495 * on failure.
2496 */
2497static struct generic_pm_domain *genpd_get_from_provider(
2498					struct of_phandle_args *genpdspec)
2499{
2500	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
2501	struct of_genpd_provider *provider;
2502
2503	if (!genpdspec)
2504		return ERR_PTR(-EINVAL);
2505
2506	mutex_lock(&of_genpd_mutex);
2507
2508	/* Check if we have such a provider in our array */
2509	list_for_each_entry(provider, &of_genpd_providers, link) {
2510		if (provider->node == genpdspec->np)
2511			genpd = provider->xlate(genpdspec, provider->data);
2512		if (!IS_ERR(genpd))
2513			break;
2514	}
2515
2516	mutex_unlock(&of_genpd_mutex);
2517
2518	return genpd;
2519}
2520
2521/**
2522 * of_genpd_add_device() - Add a device to an I/O PM domain
2523 * @genpdspec: OF phandle args to use for look-up PM domain
2524 * @dev: Device to be added.
2525 *
2526 * Looks-up an I/O PM domain based upon phandle args provided and adds
2527 * the device to the PM domain. Returns a negative error code on failure.
2528 */
2529int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
2530{
2531	struct generic_pm_domain *genpd;
2532	int ret;
2533
2534	if (!dev)
2535		return -EINVAL;
2536
2537	mutex_lock(&gpd_list_lock);
2538
2539	genpd = genpd_get_from_provider(genpdspec);
2540	if (IS_ERR(genpd)) {
2541		ret = PTR_ERR(genpd);
2542		goto out;
2543	}
2544
2545	ret = genpd_add_device(genpd, dev, dev);
2546
2547out:
2548	mutex_unlock(&gpd_list_lock);
2549
2550	return ret;
2551}
2552EXPORT_SYMBOL_GPL(of_genpd_add_device);
2553
2554/**
2555 * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
2556 * @parent_spec: OF phandle args to use for parent PM domain look-up
2557 * @subdomain_spec: OF phandle args to use for subdomain look-up
2558 *
2559 * Looks-up a parent PM domain and subdomain based upon phandle args
2560 * provided and adds the subdomain to the parent PM domain. Returns a
2561 * negative error code on failure.
2562 */
2563int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
2564			   struct of_phandle_args *subdomain_spec)
2565{
2566	struct generic_pm_domain *parent, *subdomain;
2567	int ret;
2568
2569	mutex_lock(&gpd_list_lock);
2570
2571	parent = genpd_get_from_provider(parent_spec);
2572	if (IS_ERR(parent)) {
2573		ret = PTR_ERR(parent);
2574		goto out;
2575	}
2576
2577	subdomain = genpd_get_from_provider(subdomain_spec);
2578	if (IS_ERR(subdomain)) {
2579		ret = PTR_ERR(subdomain);
2580		goto out;
2581	}
2582
2583	ret = genpd_add_subdomain(parent, subdomain);
2584
2585out:
2586	mutex_unlock(&gpd_list_lock);
2587
2588	return ret == -ENOENT ? -EPROBE_DEFER : ret;
2589}
2590EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
2591
2592/**
2593 * of_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
2594 * @parent_spec: OF phandle args to use for parent PM domain look-up
2595 * @subdomain_spec: OF phandle args to use for subdomain look-up
2596 *
2597 * Looks-up a parent PM domain and subdomain based upon phandle args
2598 * provided and removes the subdomain from the parent PM domain. Returns a
2599 * negative error code on failure.
2600 */
2601int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
2602			      struct of_phandle_args *subdomain_spec)
2603{
2604	struct generic_pm_domain *parent, *subdomain;
2605	int ret;
2606
2607	mutex_lock(&gpd_list_lock);
2608
2609	parent = genpd_get_from_provider(parent_spec);
2610	if (IS_ERR(parent)) {
2611		ret = PTR_ERR(parent);
2612		goto out;
2613	}
2614
2615	subdomain = genpd_get_from_provider(subdomain_spec);
2616	if (IS_ERR(subdomain)) {
2617		ret = PTR_ERR(subdomain);
2618		goto out;
2619	}
2620
2621	ret = pm_genpd_remove_subdomain(parent, subdomain);
2622
2623out:
2624	mutex_unlock(&gpd_list_lock);
2625
2626	return ret;
2627}
2628EXPORT_SYMBOL_GPL(of_genpd_remove_subdomain);
2629
2630/**
2631 * of_genpd_remove_last - Remove the last PM domain registered for a provider
2632 * @np: Pointer to device node associated with provider
2633 *
2634 * Find the last PM domain that was added by a particular provider and
2635 * remove this PM domain from the list of PM domains. The provider is
2636 * identified by the 'provider' device structure that is passed. The PM
2637 * domain will only be removed, if the provider associated with domain
2638 * has been removed.
2639 *
2640 * Returns a valid pointer to struct generic_pm_domain on success or
2641 * ERR_PTR() on failure.
2642 */
2643struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
2644{
2645	struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
2646	int ret;
2647
2648	if (IS_ERR_OR_NULL(np))
2649		return ERR_PTR(-EINVAL);
2650
2651	mutex_lock(&gpd_list_lock);
2652	list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
2653		if (gpd->provider == &np->fwnode) {
2654			ret = genpd_remove(gpd);
2655			genpd = ret ? ERR_PTR(ret) : gpd;
2656			break;
2657		}
2658	}
2659	mutex_unlock(&gpd_list_lock);
2660
2661	return genpd;
2662}
2663EXPORT_SYMBOL_GPL(of_genpd_remove_last);
2664
2665static void genpd_release_dev(struct device *dev)
2666{
2667	of_node_put(dev->of_node);
2668	kfree(dev);
2669}
2670
2671static const struct bus_type genpd_bus_type = {
2672	.name		= "genpd",
2673};
2674
2675/**
2676 * genpd_dev_pm_detach - Detach a device from its PM domain.
2677 * @dev: Device to detach.
2678 * @power_off: Currently not used
2679 *
2680 * Try to locate a corresponding generic PM domain, which the device was
2681 * attached to previously. If such is found, the device is detached from it.
2682 */
2683static void genpd_dev_pm_detach(struct device *dev, bool power_off)
2684{
2685	struct generic_pm_domain *pd;
2686	unsigned int i;
2687	int ret = 0;
2688
2689	pd = dev_to_genpd(dev);
2690	if (IS_ERR(pd))
2691		return;
2692
2693	dev_dbg(dev, "removing from PM domain %s\n", pd->name);
2694
2695	/* Drop the default performance state */
2696	if (dev_gpd_data(dev)->default_pstate) {
2697		dev_pm_genpd_set_performance_state(dev, 0);
2698		dev_gpd_data(dev)->default_pstate = 0;
2699	}
2700
2701	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2702		ret = genpd_remove_device(pd, dev);
2703		if (ret != -EAGAIN)
2704			break;
2705
2706		mdelay(i);
2707		cond_resched();
2708	}
2709
2710	if (ret < 0) {
2711		dev_err(dev, "failed to remove from PM domain %s: %d",
2712			pd->name, ret);
2713		return;
2714	}
2715
2716	/* Check if PM domain can be powered off after removing this device. */
2717	genpd_queue_power_off_work(pd);
2718
2719	/* Unregister the device if it was created by genpd. */
2720	if (dev->bus == &genpd_bus_type)
2721		device_unregister(dev);
2722}
2723
2724static void genpd_dev_pm_sync(struct device *dev)
2725{
2726	struct generic_pm_domain *pd;
2727
2728	pd = dev_to_genpd(dev);
2729	if (IS_ERR(pd))
2730		return;
2731
2732	genpd_queue_power_off_work(pd);
2733}
2734
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2735static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
2736				 unsigned int index, bool power_on)
 
2737{
2738	struct of_phandle_args pd_args;
2739	struct generic_pm_domain *pd;
2740	int pstate;
2741	int ret;
2742
2743	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
2744				"#power-domain-cells", index, &pd_args);
2745	if (ret < 0)
2746		return ret;
2747
2748	mutex_lock(&gpd_list_lock);
2749	pd = genpd_get_from_provider(&pd_args);
2750	of_node_put(pd_args.np);
2751	if (IS_ERR(pd)) {
2752		mutex_unlock(&gpd_list_lock);
2753		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
2754			__func__, PTR_ERR(pd));
2755		return driver_deferred_probe_check_state(base_dev);
2756	}
2757
2758	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
2759
2760	ret = genpd_add_device(pd, dev, base_dev);
2761	mutex_unlock(&gpd_list_lock);
2762
2763	if (ret < 0)
2764		return dev_err_probe(dev, ret, "failed to add to PM domain %s\n", pd->name);
2765
2766	dev->pm_domain->detach = genpd_dev_pm_detach;
2767	dev->pm_domain->sync = genpd_dev_pm_sync;
2768
2769	/* Set the default performance state */
2770	pstate = of_get_required_opp_performance_state(dev->of_node, index);
2771	if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
2772		ret = pstate;
2773		goto err;
2774	} else if (pstate > 0) {
2775		ret = dev_pm_genpd_set_performance_state(dev, pstate);
2776		if (ret)
2777			goto err;
2778		dev_gpd_data(dev)->default_pstate = pstate;
2779	}
2780
 
 
 
 
2781	if (power_on) {
2782		genpd_lock(pd);
2783		ret = genpd_power_on(pd, 0);
2784		genpd_unlock(pd);
2785	}
2786
2787	if (ret) {
2788		/* Drop the default performance state */
2789		if (dev_gpd_data(dev)->default_pstate) {
2790			dev_pm_genpd_set_performance_state(dev, 0);
2791			dev_gpd_data(dev)->default_pstate = 0;
2792		}
2793
2794		genpd_remove_device(pd, dev);
2795		return -EPROBE_DEFER;
2796	}
2797
2798	return 1;
2799
2800err:
2801	dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
2802		pd->name, ret);
2803	genpd_remove_device(pd, dev);
2804	return ret;
2805}
2806
2807/**
2808 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
2809 * @dev: Device to attach.
2810 *
2811 * Parse device's OF node to find a PM domain specifier. If such is found,
2812 * attaches the device to retrieved pm_domain ops.
2813 *
2814 * Returns 1 on successfully attached PM domain, 0 when the device don't need a
2815 * PM domain or when multiple power-domains exists for it, else a negative error
2816 * code. Note that if a power-domain exists for the device, but it cannot be
2817 * found or turned on, then return -EPROBE_DEFER to ensure that the device is
2818 * not probed and to re-try again later.
2819 */
2820int genpd_dev_pm_attach(struct device *dev)
2821{
2822	if (!dev->of_node)
2823		return 0;
2824
2825	/*
2826	 * Devices with multiple PM domains must be attached separately, as we
2827	 * can only attach one PM domain per device.
2828	 */
2829	if (of_count_phandle_with_args(dev->of_node, "power-domains",
2830				       "#power-domain-cells") != 1)
2831		return 0;
2832
2833	return __genpd_dev_pm_attach(dev, dev, 0, true);
2834}
2835EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
2836
2837/**
2838 * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
2839 * @dev: The device used to lookup the PM domain.
2840 * @index: The index of the PM domain.
2841 *
2842 * Parse device's OF node to find a PM domain specifier at the provided @index.
2843 * If such is found, creates a virtual device and attaches it to the retrieved
2844 * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
2845 * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
2846 *
2847 * Returns the created virtual device if successfully attached PM domain, NULL
2848 * when the device don't need a PM domain, else an ERR_PTR() in case of
2849 * failures. If a power-domain exists for the device, but cannot be found or
2850 * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
2851 * is not probed and to re-try again later.
2852 */
2853struct device *genpd_dev_pm_attach_by_id(struct device *dev,
2854					 unsigned int index)
2855{
2856	struct device *virt_dev;
2857	int num_domains;
2858	int ret;
2859
2860	if (!dev->of_node)
2861		return NULL;
2862
2863	/* Verify that the index is within a valid range. */
2864	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
2865						 "#power-domain-cells");
2866	if (index >= num_domains)
2867		return NULL;
2868
2869	/* Allocate and register device on the genpd bus. */
2870	virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
2871	if (!virt_dev)
2872		return ERR_PTR(-ENOMEM);
2873
2874	dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
2875	virt_dev->bus = &genpd_bus_type;
2876	virt_dev->release = genpd_release_dev;
2877	virt_dev->of_node = of_node_get(dev->of_node);
2878
2879	ret = device_register(virt_dev);
2880	if (ret) {
2881		put_device(virt_dev);
2882		return ERR_PTR(ret);
2883	}
2884
2885	/* Try to attach the device to the PM domain at the specified index. */
2886	ret = __genpd_dev_pm_attach(virt_dev, dev, index, false);
2887	if (ret < 1) {
2888		device_unregister(virt_dev);
2889		return ret ? ERR_PTR(ret) : NULL;
2890	}
2891
2892	pm_runtime_enable(virt_dev);
2893	genpd_queue_power_off_work(dev_to_genpd(virt_dev));
2894
2895	return virt_dev;
2896}
2897EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
2898
2899/**
2900 * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
2901 * @dev: The device used to lookup the PM domain.
2902 * @name: The name of the PM domain.
2903 *
2904 * Parse device's OF node to find a PM domain specifier using the
2905 * power-domain-names DT property. For further description see
2906 * genpd_dev_pm_attach_by_id().
2907 */
2908struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
2909{
2910	int index;
2911
2912	if (!dev->of_node)
2913		return NULL;
2914
2915	index = of_property_match_string(dev->of_node, "power-domain-names",
2916					 name);
2917	if (index < 0)
2918		return NULL;
2919
2920	return genpd_dev_pm_attach_by_id(dev, index);
2921}
2922
2923static const struct of_device_id idle_state_match[] = {
2924	{ .compatible = "domain-idle-state", },
2925	{ }
2926};
2927
2928static int genpd_parse_state(struct genpd_power_state *genpd_state,
2929				    struct device_node *state_node)
2930{
2931	int err;
2932	u32 residency;
2933	u32 entry_latency, exit_latency;
2934
2935	err = of_property_read_u32(state_node, "entry-latency-us",
2936						&entry_latency);
2937	if (err) {
2938		pr_debug(" * %pOF missing entry-latency-us property\n",
2939			 state_node);
2940		return -EINVAL;
2941	}
2942
2943	err = of_property_read_u32(state_node, "exit-latency-us",
2944						&exit_latency);
2945	if (err) {
2946		pr_debug(" * %pOF missing exit-latency-us property\n",
2947			 state_node);
2948		return -EINVAL;
2949	}
2950
2951	err = of_property_read_u32(state_node, "min-residency-us", &residency);
2952	if (!err)
2953		genpd_state->residency_ns = 1000LL * residency;
2954
2955	genpd_state->power_on_latency_ns = 1000LL * exit_latency;
2956	genpd_state->power_off_latency_ns = 1000LL * entry_latency;
2957	genpd_state->fwnode = &state_node->fwnode;
2958
2959	return 0;
2960}
2961
2962static int genpd_iterate_idle_states(struct device_node *dn,
2963				     struct genpd_power_state *states)
2964{
2965	int ret;
2966	struct of_phandle_iterator it;
2967	struct device_node *np;
2968	int i = 0;
2969
2970	ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
2971	if (ret <= 0)
2972		return ret == -ENOENT ? 0 : ret;
2973
2974	/* Loop over the phandles until all the requested entry is found */
2975	of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
2976		np = it.node;
2977		if (!of_match_node(idle_state_match, np))
2978			continue;
2979
2980		if (!of_device_is_available(np))
2981			continue;
2982
2983		if (states) {
2984			ret = genpd_parse_state(&states[i], np);
2985			if (ret) {
2986				pr_err("Parsing idle state node %pOF failed with err %d\n",
2987				       np, ret);
2988				of_node_put(np);
2989				return ret;
2990			}
2991		}
2992		i++;
2993	}
2994
2995	return i;
2996}
2997
2998/**
2999 * of_genpd_parse_idle_states: Return array of idle states for the genpd.
3000 *
3001 * @dn: The genpd device node
3002 * @states: The pointer to which the state array will be saved.
3003 * @n: The count of elements in the array returned from this function.
3004 *
3005 * Returns the device states parsed from the OF node. The memory for the states
3006 * is allocated by this function and is the responsibility of the caller to
3007 * free the memory after use. If any or zero compatible domain idle states is
3008 * found it returns 0 and in case of errors, a negative error code is returned.
3009 */
3010int of_genpd_parse_idle_states(struct device_node *dn,
3011			struct genpd_power_state **states, int *n)
3012{
3013	struct genpd_power_state *st;
3014	int ret;
3015
3016	ret = genpd_iterate_idle_states(dn, NULL);
3017	if (ret < 0)
3018		return ret;
3019
3020	if (!ret) {
3021		*states = NULL;
3022		*n = 0;
3023		return 0;
3024	}
3025
3026	st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
3027	if (!st)
3028		return -ENOMEM;
3029
3030	ret = genpd_iterate_idle_states(dn, st);
3031	if (ret <= 0) {
3032		kfree(st);
3033		return ret < 0 ? ret : -EINVAL;
3034	}
3035
3036	*states = st;
3037	*n = ret;
3038
3039	return 0;
3040}
3041EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
3042
3043static int __init genpd_bus_init(void)
3044{
3045	return bus_register(&genpd_bus_type);
3046}
3047core_initcall(genpd_bus_init);
3048
3049#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
3050
3051
3052/***        debugfs support        ***/
3053
3054#ifdef CONFIG_DEBUG_FS
3055/*
3056 * TODO: This function is a slightly modified version of rtpm_status_show
3057 * from sysfs.c, so generalize it.
3058 */
3059static void rtpm_status_str(struct seq_file *s, struct device *dev)
3060{
3061	static const char * const status_lookup[] = {
3062		[RPM_ACTIVE] = "active",
3063		[RPM_RESUMING] = "resuming",
3064		[RPM_SUSPENDED] = "suspended",
3065		[RPM_SUSPENDING] = "suspending"
3066	};
3067	const char *p = "";
3068
3069	if (dev->power.runtime_error)
3070		p = "error";
3071	else if (dev->power.disable_depth)
3072		p = "unsupported";
3073	else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
3074		p = status_lookup[dev->power.runtime_status];
3075	else
3076		WARN_ON(1);
3077
3078	seq_printf(s, "%-25s  ", p);
3079}
3080
3081static void perf_status_str(struct seq_file *s, struct device *dev)
3082{
3083	struct generic_pm_domain_data *gpd_data;
3084
3085	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
3086	seq_put_decimal_ull(s, "", gpd_data->performance_state);
 
 
 
 
 
 
 
 
 
 
3087}
3088
3089static int genpd_summary_one(struct seq_file *s,
3090			struct generic_pm_domain *genpd)
3091{
3092	static const char * const status_lookup[] = {
3093		[GENPD_STATE_ON] = "on",
3094		[GENPD_STATE_OFF] = "off"
3095	};
3096	struct pm_domain_data *pm_data;
3097	const char *kobj_path;
3098	struct gpd_link *link;
3099	char state[16];
3100	int ret;
3101
3102	ret = genpd_lock_interruptible(genpd);
3103	if (ret)
3104		return -ERESTARTSYS;
3105
3106	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
3107		goto exit;
3108	if (!genpd_status_on(genpd))
3109		snprintf(state, sizeof(state), "%s-%u",
3110			 status_lookup[genpd->status], genpd->state_idx);
3111	else
3112		snprintf(state, sizeof(state), "%s",
3113			 status_lookup[genpd->status]);
3114	seq_printf(s, "%-30s  %-50s %u", genpd->name, state, genpd->performance_state);
3115
3116	/*
3117	 * Modifications on the list require holding locks on both
3118	 * parent and child, so we are safe.
3119	 * Also genpd->name is immutable.
3120	 */
3121	list_for_each_entry(link, &genpd->parent_links, parent_node) {
3122		if (list_is_first(&link->parent_node, &genpd->parent_links))
3123			seq_printf(s, "\n%48s", " ");
3124		seq_printf(s, "%s", link->child->name);
3125		if (!list_is_last(&link->parent_node, &genpd->parent_links))
3126			seq_puts(s, ", ");
3127	}
3128
3129	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
3130		kobj_path = kobject_get_path(&pm_data->dev->kobj,
3131				genpd_is_irq_safe(genpd) ?
3132				GFP_ATOMIC : GFP_KERNEL);
3133		if (kobj_path == NULL)
3134			continue;
3135
3136		seq_printf(s, "\n    %-50s  ", kobj_path);
3137		rtpm_status_str(s, pm_data->dev);
3138		perf_status_str(s, pm_data->dev);
3139		kfree(kobj_path);
3140	}
3141
3142	seq_puts(s, "\n");
3143exit:
3144	genpd_unlock(genpd);
3145
3146	return 0;
3147}
3148
3149static int summary_show(struct seq_file *s, void *data)
3150{
3151	struct generic_pm_domain *genpd;
3152	int ret = 0;
3153
3154	seq_puts(s, "domain                          status          children                           performance\n");
3155	seq_puts(s, "    /device                                             runtime status\n");
3156	seq_puts(s, "----------------------------------------------------------------------------------------------\n");
3157
3158	ret = mutex_lock_interruptible(&gpd_list_lock);
3159	if (ret)
3160		return -ERESTARTSYS;
3161
3162	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
3163		ret = genpd_summary_one(s, genpd);
3164		if (ret)
3165			break;
3166	}
3167	mutex_unlock(&gpd_list_lock);
3168
3169	return ret;
3170}
3171
3172static int status_show(struct seq_file *s, void *data)
3173{
3174	static const char * const status_lookup[] = {
3175		[GENPD_STATE_ON] = "on",
3176		[GENPD_STATE_OFF] = "off"
3177	};
3178
3179	struct generic_pm_domain *genpd = s->private;
3180	int ret = 0;
3181
3182	ret = genpd_lock_interruptible(genpd);
3183	if (ret)
3184		return -ERESTARTSYS;
3185
3186	if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
3187		goto exit;
3188
3189	if (genpd->status == GENPD_STATE_OFF)
3190		seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
3191			genpd->state_idx);
3192	else
3193		seq_printf(s, "%s\n", status_lookup[genpd->status]);
3194exit:
3195	genpd_unlock(genpd);
3196	return ret;
3197}
3198
3199static int sub_domains_show(struct seq_file *s, void *data)
3200{
3201	struct generic_pm_domain *genpd = s->private;
3202	struct gpd_link *link;
3203	int ret = 0;
3204
3205	ret = genpd_lock_interruptible(genpd);
3206	if (ret)
3207		return -ERESTARTSYS;
3208
3209	list_for_each_entry(link, &genpd->parent_links, parent_node)
3210		seq_printf(s, "%s\n", link->child->name);
3211
3212	genpd_unlock(genpd);
3213	return ret;
3214}
3215
3216static int idle_states_show(struct seq_file *s, void *data)
3217{
3218	struct generic_pm_domain *genpd = s->private;
3219	u64 now, delta, idle_time = 0;
3220	unsigned int i;
3221	int ret = 0;
3222
3223	ret = genpd_lock_interruptible(genpd);
3224	if (ret)
3225		return -ERESTARTSYS;
3226
3227	seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
3228
3229	for (i = 0; i < genpd->state_count; i++) {
3230		idle_time += genpd->states[i].idle_time;
3231
3232		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3233			now = ktime_get_mono_fast_ns();
3234			if (now > genpd->accounting_time) {
3235				delta = now - genpd->accounting_time;
3236				idle_time += delta;
3237			}
3238		}
3239
3240		do_div(idle_time, NSEC_PER_MSEC);
3241		seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
3242			   genpd->states[i].usage, genpd->states[i].rejected);
3243	}
3244
3245	genpd_unlock(genpd);
3246	return ret;
3247}
3248
3249static int active_time_show(struct seq_file *s, void *data)
3250{
3251	struct generic_pm_domain *genpd = s->private;
3252	u64 now, on_time, delta = 0;
3253	int ret = 0;
3254
3255	ret = genpd_lock_interruptible(genpd);
3256	if (ret)
3257		return -ERESTARTSYS;
3258
3259	if (genpd->status == GENPD_STATE_ON) {
3260		now = ktime_get_mono_fast_ns();
3261		if (now > genpd->accounting_time)
3262			delta = now - genpd->accounting_time;
3263	}
3264
3265	on_time = genpd->on_time + delta;
3266	do_div(on_time, NSEC_PER_MSEC);
3267	seq_printf(s, "%llu ms\n", on_time);
3268
3269	genpd_unlock(genpd);
3270	return ret;
3271}
3272
3273static int total_idle_time_show(struct seq_file *s, void *data)
3274{
3275	struct generic_pm_domain *genpd = s->private;
3276	u64 now, delta, total = 0;
3277	unsigned int i;
3278	int ret = 0;
3279
3280	ret = genpd_lock_interruptible(genpd);
3281	if (ret)
3282		return -ERESTARTSYS;
3283
3284	for (i = 0; i < genpd->state_count; i++) {
3285		total += genpd->states[i].idle_time;
3286
3287		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3288			now = ktime_get_mono_fast_ns();
3289			if (now > genpd->accounting_time) {
3290				delta = now - genpd->accounting_time;
3291				total += delta;
3292			}
3293		}
3294	}
3295
3296	do_div(total, NSEC_PER_MSEC);
3297	seq_printf(s, "%llu ms\n", total);
3298
3299	genpd_unlock(genpd);
3300	return ret;
3301}
3302
3303
3304static int devices_show(struct seq_file *s, void *data)
3305{
3306	struct generic_pm_domain *genpd = s->private;
3307	struct pm_domain_data *pm_data;
3308	const char *kobj_path;
3309	int ret = 0;
3310
3311	ret = genpd_lock_interruptible(genpd);
3312	if (ret)
3313		return -ERESTARTSYS;
3314
3315	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
3316		kobj_path = kobject_get_path(&pm_data->dev->kobj,
3317				genpd_is_irq_safe(genpd) ?
3318				GFP_ATOMIC : GFP_KERNEL);
3319		if (kobj_path == NULL)
3320			continue;
3321
3322		seq_printf(s, "%s\n", kobj_path);
3323		kfree(kobj_path);
3324	}
3325
3326	genpd_unlock(genpd);
3327	return ret;
3328}
3329
3330static int perf_state_show(struct seq_file *s, void *data)
3331{
3332	struct generic_pm_domain *genpd = s->private;
3333
3334	if (genpd_lock_interruptible(genpd))
3335		return -ERESTARTSYS;
3336
3337	seq_printf(s, "%u\n", genpd->performance_state);
3338
3339	genpd_unlock(genpd);
3340	return 0;
3341}
3342
3343DEFINE_SHOW_ATTRIBUTE(summary);
3344DEFINE_SHOW_ATTRIBUTE(status);
3345DEFINE_SHOW_ATTRIBUTE(sub_domains);
3346DEFINE_SHOW_ATTRIBUTE(idle_states);
3347DEFINE_SHOW_ATTRIBUTE(active_time);
3348DEFINE_SHOW_ATTRIBUTE(total_idle_time);
3349DEFINE_SHOW_ATTRIBUTE(devices);
3350DEFINE_SHOW_ATTRIBUTE(perf_state);
3351
3352static void genpd_debug_add(struct generic_pm_domain *genpd)
3353{
3354	struct dentry *d;
3355
3356	if (!genpd_debugfs_dir)
3357		return;
3358
3359	d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
3360
3361	debugfs_create_file("current_state", 0444,
3362			    d, genpd, &status_fops);
3363	debugfs_create_file("sub_domains", 0444,
3364			    d, genpd, &sub_domains_fops);
3365	debugfs_create_file("idle_states", 0444,
3366			    d, genpd, &idle_states_fops);
3367	debugfs_create_file("active_time", 0444,
3368			    d, genpd, &active_time_fops);
3369	debugfs_create_file("total_idle_time", 0444,
3370			    d, genpd, &total_idle_time_fops);
3371	debugfs_create_file("devices", 0444,
3372			    d, genpd, &devices_fops);
3373	if (genpd->set_performance_state)
3374		debugfs_create_file("perf_state", 0444,
3375				    d, genpd, &perf_state_fops);
3376}
3377
3378static int __init genpd_debug_init(void)
3379{
3380	struct generic_pm_domain *genpd;
3381
3382	genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
3383
3384	debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
3385			    NULL, &summary_fops);
3386
3387	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
3388		genpd_debug_add(genpd);
3389
3390	return 0;
3391}
3392late_initcall(genpd_debug_init);
3393
3394static void __exit genpd_debug_exit(void)
3395{
3396	debugfs_remove_recursive(genpd_debugfs_dir);
3397}
3398__exitcall(genpd_debug_exit);
3399#endif /* CONFIG_DEBUG_FS */