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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#include "power.h"
27
28#define GENPD_RETRY_MAX_MS 250 /* Approximate */
29
30#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
31({ \
32 type (*__routine)(struct device *__d); \
33 type __ret = (type)0; \
34 \
35 __routine = genpd->dev_ops.callback; \
36 if (__routine) { \
37 __ret = __routine(dev); \
38 } \
39 __ret; \
40})
41
42static LIST_HEAD(gpd_list);
43static DEFINE_MUTEX(gpd_list_lock);
44
45struct genpd_lock_ops {
46 void (*lock)(struct generic_pm_domain *genpd);
47 void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
48 int (*lock_interruptible)(struct generic_pm_domain *genpd);
49 void (*unlock)(struct generic_pm_domain *genpd);
50};
51
52static void genpd_lock_mtx(struct generic_pm_domain *genpd)
53{
54 mutex_lock(&genpd->mlock);
55}
56
57static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
58 int depth)
59{
60 mutex_lock_nested(&genpd->mlock, depth);
61}
62
63static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
64{
65 return mutex_lock_interruptible(&genpd->mlock);
66}
67
68static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
69{
70 return mutex_unlock(&genpd->mlock);
71}
72
73static const struct genpd_lock_ops genpd_mtx_ops = {
74 .lock = genpd_lock_mtx,
75 .lock_nested = genpd_lock_nested_mtx,
76 .lock_interruptible = genpd_lock_interruptible_mtx,
77 .unlock = genpd_unlock_mtx,
78};
79
80static void genpd_lock_spin(struct generic_pm_domain *genpd)
81 __acquires(&genpd->slock)
82{
83 unsigned long flags;
84
85 spin_lock_irqsave(&genpd->slock, flags);
86 genpd->lock_flags = flags;
87}
88
89static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
90 int depth)
91 __acquires(&genpd->slock)
92{
93 unsigned long flags;
94
95 spin_lock_irqsave_nested(&genpd->slock, flags, depth);
96 genpd->lock_flags = flags;
97}
98
99static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
100 __acquires(&genpd->slock)
101{
102 unsigned long flags;
103
104 spin_lock_irqsave(&genpd->slock, flags);
105 genpd->lock_flags = flags;
106 return 0;
107}
108
109static void genpd_unlock_spin(struct generic_pm_domain *genpd)
110 __releases(&genpd->slock)
111{
112 spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
113}
114
115static const struct genpd_lock_ops genpd_spin_ops = {
116 .lock = genpd_lock_spin,
117 .lock_nested = genpd_lock_nested_spin,
118 .lock_interruptible = genpd_lock_interruptible_spin,
119 .unlock = genpd_unlock_spin,
120};
121
122#define genpd_lock(p) p->lock_ops->lock(p)
123#define genpd_lock_nested(p, d) p->lock_ops->lock_nested(p, d)
124#define genpd_lock_interruptible(p) p->lock_ops->lock_interruptible(p)
125#define genpd_unlock(p) p->lock_ops->unlock(p)
126
127#define genpd_status_on(genpd) (genpd->status == GENPD_STATE_ON)
128#define genpd_is_irq_safe(genpd) (genpd->flags & GENPD_FLAG_IRQ_SAFE)
129#define genpd_is_always_on(genpd) (genpd->flags & GENPD_FLAG_ALWAYS_ON)
130#define genpd_is_active_wakeup(genpd) (genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
131#define genpd_is_cpu_domain(genpd) (genpd->flags & GENPD_FLAG_CPU_DOMAIN)
132#define genpd_is_rpm_always_on(genpd) (genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
133
134static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
135 const struct generic_pm_domain *genpd)
136{
137 bool ret;
138
139 ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
140
141 /*
142 * Warn once if an IRQ safe device is attached to a domain, which
143 * callbacks are allowed to sleep. This indicates a suboptimal
144 * configuration for PM, but it doesn't matter for an always on domain.
145 */
146 if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
147 return ret;
148
149 if (ret)
150 dev_warn_once(dev, "PM domain %s will not be powered off\n",
151 genpd->name);
152
153 return ret;
154}
155
156static int genpd_runtime_suspend(struct device *dev);
157
158/*
159 * Get the generic PM domain for a particular struct device.
160 * This validates the struct device pointer, the PM domain pointer,
161 * and checks that the PM domain pointer is a real generic PM domain.
162 * Any failure results in NULL being returned.
163 */
164static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
165{
166 if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
167 return NULL;
168
169 /* A genpd's always have its ->runtime_suspend() callback assigned. */
170 if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
171 return pd_to_genpd(dev->pm_domain);
172
173 return NULL;
174}
175
176/*
177 * This should only be used where we are certain that the pm_domain
178 * attached to the device is a genpd domain.
179 */
180static struct generic_pm_domain *dev_to_genpd(struct device *dev)
181{
182 if (IS_ERR_OR_NULL(dev->pm_domain))
183 return ERR_PTR(-EINVAL);
184
185 return pd_to_genpd(dev->pm_domain);
186}
187
188static int genpd_stop_dev(const struct generic_pm_domain *genpd,
189 struct device *dev)
190{
191 return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
192}
193
194static int genpd_start_dev(const struct generic_pm_domain *genpd,
195 struct device *dev)
196{
197 return GENPD_DEV_CALLBACK(genpd, int, start, dev);
198}
199
200static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
201{
202 bool ret = false;
203
204 if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
205 ret = !!atomic_dec_and_test(&genpd->sd_count);
206
207 return ret;
208}
209
210static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
211{
212 atomic_inc(&genpd->sd_count);
213 smp_mb__after_atomic();
214}
215
216#ifdef CONFIG_DEBUG_FS
217static struct dentry *genpd_debugfs_dir;
218
219static void genpd_debug_add(struct generic_pm_domain *genpd);
220
221static void genpd_debug_remove(struct generic_pm_domain *genpd)
222{
223 struct dentry *d;
224
225 if (!genpd_debugfs_dir)
226 return;
227
228 d = debugfs_lookup(genpd->name, genpd_debugfs_dir);
229 debugfs_remove(d);
230}
231
232static void genpd_update_accounting(struct generic_pm_domain *genpd)
233{
234 u64 delta, now;
235
236 now = ktime_get_mono_fast_ns();
237 if (now <= genpd->accounting_time)
238 return;
239
240 delta = now - genpd->accounting_time;
241
242 /*
243 * If genpd->status is active, it means we are just
244 * out of off and so update the idle time and vice
245 * versa.
246 */
247 if (genpd->status == GENPD_STATE_ON)
248 genpd->states[genpd->state_idx].idle_time += delta;
249 else
250 genpd->on_time += delta;
251
252 genpd->accounting_time = now;
253}
254#else
255static inline void genpd_debug_add(struct generic_pm_domain *genpd) {}
256static inline void genpd_debug_remove(struct generic_pm_domain *genpd) {}
257static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
258#endif
259
260static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
261 unsigned int state)
262{
263 struct generic_pm_domain_data *pd_data;
264 struct pm_domain_data *pdd;
265 struct gpd_link *link;
266
267 /* New requested state is same as Max requested state */
268 if (state == genpd->performance_state)
269 return state;
270
271 /* New requested state is higher than Max requested state */
272 if (state > genpd->performance_state)
273 return state;
274
275 /* Traverse all devices within the domain */
276 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
277 pd_data = to_gpd_data(pdd);
278
279 if (pd_data->performance_state > state)
280 state = pd_data->performance_state;
281 }
282
283 /*
284 * Traverse all sub-domains within the domain. This can be
285 * done without any additional locking as the link->performance_state
286 * field is protected by the parent genpd->lock, which is already taken.
287 *
288 * Also note that link->performance_state (subdomain's performance state
289 * requirement to parent domain) is different from
290 * link->child->performance_state (current performance state requirement
291 * of the devices/sub-domains of the subdomain) and so can have a
292 * different value.
293 *
294 * Note that we also take vote from powered-off sub-domains into account
295 * as the same is done for devices right now.
296 */
297 list_for_each_entry(link, &genpd->parent_links, parent_node) {
298 if (link->performance_state > state)
299 state = link->performance_state;
300 }
301
302 return state;
303}
304
305static int genpd_xlate_performance_state(struct generic_pm_domain *genpd,
306 struct generic_pm_domain *parent,
307 unsigned int pstate)
308{
309 if (!parent->set_performance_state)
310 return pstate;
311
312 return dev_pm_opp_xlate_performance_state(genpd->opp_table,
313 parent->opp_table,
314 pstate);
315}
316
317static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
318 unsigned int state, int depth)
319{
320 struct generic_pm_domain *parent;
321 struct gpd_link *link;
322 int parent_state, ret;
323
324 if (state == genpd->performance_state)
325 return 0;
326
327 /* Propagate to parents of genpd */
328 list_for_each_entry(link, &genpd->child_links, child_node) {
329 parent = link->parent;
330
331 /* Find parent's performance state */
332 ret = genpd_xlate_performance_state(genpd, parent, state);
333 if (unlikely(ret < 0))
334 goto err;
335
336 parent_state = ret;
337
338 genpd_lock_nested(parent, depth + 1);
339
340 link->prev_performance_state = link->performance_state;
341 link->performance_state = parent_state;
342 parent_state = _genpd_reeval_performance_state(parent,
343 parent_state);
344 ret = _genpd_set_performance_state(parent, parent_state, depth + 1);
345 if (ret)
346 link->performance_state = link->prev_performance_state;
347
348 genpd_unlock(parent);
349
350 if (ret)
351 goto err;
352 }
353
354 if (genpd->set_performance_state) {
355 ret = genpd->set_performance_state(genpd, state);
356 if (ret)
357 goto err;
358 }
359
360 genpd->performance_state = state;
361 return 0;
362
363err:
364 /* Encountered an error, lets rollback */
365 list_for_each_entry_continue_reverse(link, &genpd->child_links,
366 child_node) {
367 parent = link->parent;
368
369 genpd_lock_nested(parent, depth + 1);
370
371 parent_state = link->prev_performance_state;
372 link->performance_state = parent_state;
373
374 parent_state = _genpd_reeval_performance_state(parent,
375 parent_state);
376 if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {
377 pr_err("%s: Failed to roll back to %d performance state\n",
378 parent->name, parent_state);
379 }
380
381 genpd_unlock(parent);
382 }
383
384 return ret;
385}
386
387static int genpd_set_performance_state(struct device *dev, unsigned int state)
388{
389 struct generic_pm_domain *genpd = dev_to_genpd(dev);
390 struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
391 unsigned int prev_state;
392 int ret;
393
394 prev_state = gpd_data->performance_state;
395 if (prev_state == state)
396 return 0;
397
398 gpd_data->performance_state = state;
399 state = _genpd_reeval_performance_state(genpd, state);
400
401 ret = _genpd_set_performance_state(genpd, state, 0);
402 if (ret)
403 gpd_data->performance_state = prev_state;
404
405 return ret;
406}
407
408static int genpd_drop_performance_state(struct device *dev)
409{
410 unsigned int prev_state = dev_gpd_data(dev)->performance_state;
411
412 if (!genpd_set_performance_state(dev, 0))
413 return prev_state;
414
415 return 0;
416}
417
418static void genpd_restore_performance_state(struct device *dev,
419 unsigned int state)
420{
421 if (state)
422 genpd_set_performance_state(dev, state);
423}
424
425/**
426 * dev_pm_genpd_set_performance_state- Set performance state of device's power
427 * domain.
428 *
429 * @dev: Device for which the performance-state needs to be set.
430 * @state: Target performance state of the device. This can be set as 0 when the
431 * device doesn't have any performance state constraints left (And so
432 * the device wouldn't participate anymore to find the target
433 * performance state of the genpd).
434 *
435 * It is assumed that the users guarantee that the genpd wouldn't be detached
436 * while this routine is getting called.
437 *
438 * Returns 0 on success and negative error values on failures.
439 */
440int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
441{
442 struct generic_pm_domain *genpd;
443 int ret = 0;
444
445 genpd = dev_to_genpd_safe(dev);
446 if (!genpd)
447 return -ENODEV;
448
449 if (WARN_ON(!dev->power.subsys_data ||
450 !dev->power.subsys_data->domain_data))
451 return -EINVAL;
452
453 genpd_lock(genpd);
454 if (pm_runtime_suspended(dev)) {
455 dev_gpd_data(dev)->rpm_pstate = state;
456 } else {
457 ret = genpd_set_performance_state(dev, state);
458 if (!ret)
459 dev_gpd_data(dev)->rpm_pstate = 0;
460 }
461 genpd_unlock(genpd);
462
463 return ret;
464}
465EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
466
467/**
468 * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup.
469 *
470 * @dev: Device to handle
471 * @next: impending interrupt/wakeup for the device
472 *
473 *
474 * Allow devices to inform of the next wakeup. It's assumed that the users
475 * guarantee that the genpd wouldn't be detached while this routine is getting
476 * called. Additionally, it's also assumed that @dev isn't runtime suspended
477 * (RPM_SUSPENDED)."
478 * Although devices are expected to update the next_wakeup after the end of
479 * their usecase as well, it is possible the devices themselves may not know
480 * about that, so stale @next will be ignored when powering off the domain.
481 */
482void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
483{
484 struct generic_pm_domain *genpd;
485 struct gpd_timing_data *td;
486
487 genpd = dev_to_genpd_safe(dev);
488 if (!genpd)
489 return;
490
491 td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
492 if (td)
493 td->next_wakeup = next;
494}
495EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
496
497/**
498 * dev_pm_genpd_get_next_hrtimer - Return the next_hrtimer for the genpd
499 * @dev: A device that is attached to the genpd.
500 *
501 * This routine should typically be called for a device, at the point of when a
502 * GENPD_NOTIFY_PRE_OFF notification has been sent for it.
503 *
504 * Returns the aggregated value of the genpd's next hrtimer or KTIME_MAX if no
505 * valid value have been set.
506 */
507ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev)
508{
509 struct generic_pm_domain *genpd;
510
511 genpd = dev_to_genpd_safe(dev);
512 if (!genpd)
513 return KTIME_MAX;
514
515 if (genpd->gd)
516 return genpd->gd->next_hrtimer;
517
518 return KTIME_MAX;
519}
520EXPORT_SYMBOL_GPL(dev_pm_genpd_get_next_hrtimer);
521
522static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
523{
524 unsigned int state_idx = genpd->state_idx;
525 ktime_t time_start;
526 s64 elapsed_ns;
527 int ret;
528
529 /* Notify consumers that we are about to power on. */
530 ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
531 GENPD_NOTIFY_PRE_ON,
532 GENPD_NOTIFY_OFF, NULL);
533 ret = notifier_to_errno(ret);
534 if (ret)
535 return ret;
536
537 if (!genpd->power_on)
538 goto out;
539
540 timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
541 if (!timed) {
542 ret = genpd->power_on(genpd);
543 if (ret)
544 goto err;
545
546 goto out;
547 }
548
549 time_start = ktime_get();
550 ret = genpd->power_on(genpd);
551 if (ret)
552 goto err;
553
554 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
555 if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
556 goto out;
557
558 genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
559 genpd->gd->max_off_time_changed = true;
560 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
561 genpd->name, "on", elapsed_ns);
562
563out:
564 raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
565 return 0;
566err:
567 raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
568 NULL);
569 return ret;
570}
571
572static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
573{
574 unsigned int state_idx = genpd->state_idx;
575 ktime_t time_start;
576 s64 elapsed_ns;
577 int ret;
578
579 /* Notify consumers that we are about to power off. */
580 ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
581 GENPD_NOTIFY_PRE_OFF,
582 GENPD_NOTIFY_ON, NULL);
583 ret = notifier_to_errno(ret);
584 if (ret)
585 return ret;
586
587 if (!genpd->power_off)
588 goto out;
589
590 timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
591 if (!timed) {
592 ret = genpd->power_off(genpd);
593 if (ret)
594 goto busy;
595
596 goto out;
597 }
598
599 time_start = ktime_get();
600 ret = genpd->power_off(genpd);
601 if (ret)
602 goto busy;
603
604 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
605 if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
606 goto out;
607
608 genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
609 genpd->gd->max_off_time_changed = true;
610 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
611 genpd->name, "off", elapsed_ns);
612
613out:
614 raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
615 NULL);
616 return 0;
617busy:
618 raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
619 return ret;
620}
621
622/**
623 * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
624 * @genpd: PM domain to power off.
625 *
626 * Queue up the execution of genpd_power_off() unless it's already been done
627 * before.
628 */
629static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
630{
631 queue_work(pm_wq, &genpd->power_off_work);
632}
633
634/**
635 * genpd_power_off - Remove power from a given PM domain.
636 * @genpd: PM domain to power down.
637 * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
638 * RPM status of the releated device is in an intermediate state, not yet turned
639 * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
640 * be RPM_SUSPENDED, while it tries to power off the PM domain.
641 * @depth: nesting count for lockdep.
642 *
643 * If all of the @genpd's devices have been suspended and all of its subdomains
644 * have been powered down, remove power from @genpd.
645 */
646static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
647 unsigned int depth)
648{
649 struct pm_domain_data *pdd;
650 struct gpd_link *link;
651 unsigned int not_suspended = 0;
652 int ret;
653
654 /*
655 * Do not try to power off the domain in the following situations:
656 * (1) The domain is already in the "power off" state.
657 * (2) System suspend is in progress.
658 */
659 if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
660 return 0;
661
662 /*
663 * Abort power off for the PM domain in the following situations:
664 * (1) The domain is configured as always on.
665 * (2) When the domain has a subdomain being powered on.
666 */
667 if (genpd_is_always_on(genpd) ||
668 genpd_is_rpm_always_on(genpd) ||
669 atomic_read(&genpd->sd_count) > 0)
670 return -EBUSY;
671
672 /*
673 * The children must be in their deepest (powered-off) states to allow
674 * the parent to be powered off. Note that, there's no need for
675 * additional locking, as powering on a child, requires the parent's
676 * lock to be acquired first.
677 */
678 list_for_each_entry(link, &genpd->parent_links, parent_node) {
679 struct generic_pm_domain *child = link->child;
680 if (child->state_idx < child->state_count - 1)
681 return -EBUSY;
682 }
683
684 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
685 /*
686 * Do not allow PM domain to be powered off, when an IRQ safe
687 * device is part of a non-IRQ safe domain.
688 */
689 if (!pm_runtime_suspended(pdd->dev) ||
690 irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
691 not_suspended++;
692 }
693
694 if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
695 return -EBUSY;
696
697 if (genpd->gov && genpd->gov->power_down_ok) {
698 if (!genpd->gov->power_down_ok(&genpd->domain))
699 return -EAGAIN;
700 }
701
702 /* Default to shallowest state. */
703 if (!genpd->gov)
704 genpd->state_idx = 0;
705
706 /* Don't power off, if a child domain is waiting to power on. */
707 if (atomic_read(&genpd->sd_count) > 0)
708 return -EBUSY;
709
710 ret = _genpd_power_off(genpd, true);
711 if (ret) {
712 genpd->states[genpd->state_idx].rejected++;
713 return ret;
714 }
715
716 genpd->status = GENPD_STATE_OFF;
717 genpd_update_accounting(genpd);
718 genpd->states[genpd->state_idx].usage++;
719
720 list_for_each_entry(link, &genpd->child_links, child_node) {
721 genpd_sd_counter_dec(link->parent);
722 genpd_lock_nested(link->parent, depth + 1);
723 genpd_power_off(link->parent, false, depth + 1);
724 genpd_unlock(link->parent);
725 }
726
727 return 0;
728}
729
730/**
731 * genpd_power_on - Restore power to a given PM domain and its parents.
732 * @genpd: PM domain to power up.
733 * @depth: nesting count for lockdep.
734 *
735 * Restore power to @genpd and all of its parents so that it is possible to
736 * resume a device belonging to it.
737 */
738static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
739{
740 struct gpd_link *link;
741 int ret = 0;
742
743 if (genpd_status_on(genpd))
744 return 0;
745
746 /*
747 * The list is guaranteed not to change while the loop below is being
748 * executed, unless one of the parents' .power_on() callbacks fiddles
749 * with it.
750 */
751 list_for_each_entry(link, &genpd->child_links, child_node) {
752 struct generic_pm_domain *parent = link->parent;
753
754 genpd_sd_counter_inc(parent);
755
756 genpd_lock_nested(parent, depth + 1);
757 ret = genpd_power_on(parent, depth + 1);
758 genpd_unlock(parent);
759
760 if (ret) {
761 genpd_sd_counter_dec(parent);
762 goto err;
763 }
764 }
765
766 ret = _genpd_power_on(genpd, true);
767 if (ret)
768 goto err;
769
770 genpd->status = GENPD_STATE_ON;
771 genpd_update_accounting(genpd);
772
773 return 0;
774
775 err:
776 list_for_each_entry_continue_reverse(link,
777 &genpd->child_links,
778 child_node) {
779 genpd_sd_counter_dec(link->parent);
780 genpd_lock_nested(link->parent, depth + 1);
781 genpd_power_off(link->parent, false, depth + 1);
782 genpd_unlock(link->parent);
783 }
784
785 return ret;
786}
787
788static int genpd_dev_pm_start(struct device *dev)
789{
790 struct generic_pm_domain *genpd = dev_to_genpd(dev);
791
792 return genpd_start_dev(genpd, dev);
793}
794
795static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
796 unsigned long val, void *ptr)
797{
798 struct generic_pm_domain_data *gpd_data;
799 struct device *dev;
800
801 gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
802 dev = gpd_data->base.dev;
803
804 for (;;) {
805 struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
806 struct pm_domain_data *pdd;
807 struct gpd_timing_data *td;
808
809 spin_lock_irq(&dev->power.lock);
810
811 pdd = dev->power.subsys_data ?
812 dev->power.subsys_data->domain_data : NULL;
813 if (pdd) {
814 td = to_gpd_data(pdd)->td;
815 if (td) {
816 td->constraint_changed = true;
817 genpd = dev_to_genpd(dev);
818 }
819 }
820
821 spin_unlock_irq(&dev->power.lock);
822
823 if (!IS_ERR(genpd)) {
824 genpd_lock(genpd);
825 genpd->gd->max_off_time_changed = true;
826 genpd_unlock(genpd);
827 }
828
829 dev = dev->parent;
830 if (!dev || dev->power.ignore_children)
831 break;
832 }
833
834 return NOTIFY_DONE;
835}
836
837/**
838 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
839 * @work: Work structure used for scheduling the execution of this function.
840 */
841static void genpd_power_off_work_fn(struct work_struct *work)
842{
843 struct generic_pm_domain *genpd;
844
845 genpd = container_of(work, struct generic_pm_domain, power_off_work);
846
847 genpd_lock(genpd);
848 genpd_power_off(genpd, false, 0);
849 genpd_unlock(genpd);
850}
851
852/**
853 * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
854 * @dev: Device to handle.
855 */
856static int __genpd_runtime_suspend(struct device *dev)
857{
858 int (*cb)(struct device *__dev);
859
860 if (dev->type && dev->type->pm)
861 cb = dev->type->pm->runtime_suspend;
862 else if (dev->class && dev->class->pm)
863 cb = dev->class->pm->runtime_suspend;
864 else if (dev->bus && dev->bus->pm)
865 cb = dev->bus->pm->runtime_suspend;
866 else
867 cb = NULL;
868
869 if (!cb && dev->driver && dev->driver->pm)
870 cb = dev->driver->pm->runtime_suspend;
871
872 return cb ? cb(dev) : 0;
873}
874
875/**
876 * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
877 * @dev: Device to handle.
878 */
879static int __genpd_runtime_resume(struct device *dev)
880{
881 int (*cb)(struct device *__dev);
882
883 if (dev->type && dev->type->pm)
884 cb = dev->type->pm->runtime_resume;
885 else if (dev->class && dev->class->pm)
886 cb = dev->class->pm->runtime_resume;
887 else if (dev->bus && dev->bus->pm)
888 cb = dev->bus->pm->runtime_resume;
889 else
890 cb = NULL;
891
892 if (!cb && dev->driver && dev->driver->pm)
893 cb = dev->driver->pm->runtime_resume;
894
895 return cb ? cb(dev) : 0;
896}
897
898/**
899 * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
900 * @dev: Device to suspend.
901 *
902 * Carry out a runtime suspend of a device under the assumption that its
903 * pm_domain field points to the domain member of an object of type
904 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
905 */
906static int genpd_runtime_suspend(struct device *dev)
907{
908 struct generic_pm_domain *genpd;
909 bool (*suspend_ok)(struct device *__dev);
910 struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
911 struct gpd_timing_data *td = gpd_data->td;
912 bool runtime_pm = pm_runtime_enabled(dev);
913 ktime_t time_start = 0;
914 s64 elapsed_ns;
915 int ret;
916
917 dev_dbg(dev, "%s()\n", __func__);
918
919 genpd = dev_to_genpd(dev);
920 if (IS_ERR(genpd))
921 return -EINVAL;
922
923 /*
924 * A runtime PM centric subsystem/driver may re-use the runtime PM
925 * callbacks for other purposes than runtime PM. In those scenarios
926 * runtime PM is disabled. Under these circumstances, we shall skip
927 * validating/measuring the PM QoS latency.
928 */
929 suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
930 if (runtime_pm && suspend_ok && !suspend_ok(dev))
931 return -EBUSY;
932
933 /* Measure suspend latency. */
934 if (td && runtime_pm)
935 time_start = ktime_get();
936
937 ret = __genpd_runtime_suspend(dev);
938 if (ret)
939 return ret;
940
941 ret = genpd_stop_dev(genpd, dev);
942 if (ret) {
943 __genpd_runtime_resume(dev);
944 return ret;
945 }
946
947 /* Update suspend latency value if the measured time exceeds it. */
948 if (td && runtime_pm) {
949 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
950 if (elapsed_ns > td->suspend_latency_ns) {
951 td->suspend_latency_ns = elapsed_ns;
952 dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
953 elapsed_ns);
954 genpd->gd->max_off_time_changed = true;
955 td->constraint_changed = true;
956 }
957 }
958
959 /*
960 * If power.irq_safe is set, this routine may be run with
961 * IRQs disabled, so suspend only if the PM domain also is irq_safe.
962 */
963 if (irq_safe_dev_in_sleep_domain(dev, genpd))
964 return 0;
965
966 genpd_lock(genpd);
967 genpd_power_off(genpd, true, 0);
968 gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
969 genpd_unlock(genpd);
970
971 return 0;
972}
973
974/**
975 * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
976 * @dev: Device to resume.
977 *
978 * Carry out a runtime resume of a device under the assumption that its
979 * pm_domain field points to the domain member of an object of type
980 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
981 */
982static int genpd_runtime_resume(struct device *dev)
983{
984 struct generic_pm_domain *genpd;
985 struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
986 struct gpd_timing_data *td = gpd_data->td;
987 bool timed = td && pm_runtime_enabled(dev);
988 ktime_t time_start = 0;
989 s64 elapsed_ns;
990 int ret;
991
992 dev_dbg(dev, "%s()\n", __func__);
993
994 genpd = dev_to_genpd(dev);
995 if (IS_ERR(genpd))
996 return -EINVAL;
997
998 /*
999 * As we don't power off a non IRQ safe domain, which holds
1000 * an IRQ safe device, we don't need to restore power to it.
1001 */
1002 if (irq_safe_dev_in_sleep_domain(dev, genpd))
1003 goto out;
1004
1005 genpd_lock(genpd);
1006 genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
1007 ret = genpd_power_on(genpd, 0);
1008 genpd_unlock(genpd);
1009
1010 if (ret)
1011 return ret;
1012
1013 out:
1014 /* Measure resume latency. */
1015 if (timed)
1016 time_start = ktime_get();
1017
1018 ret = genpd_start_dev(genpd, dev);
1019 if (ret)
1020 goto err_poweroff;
1021
1022 ret = __genpd_runtime_resume(dev);
1023 if (ret)
1024 goto err_stop;
1025
1026 /* Update resume latency value if the measured time exceeds it. */
1027 if (timed) {
1028 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
1029 if (elapsed_ns > td->resume_latency_ns) {
1030 td->resume_latency_ns = elapsed_ns;
1031 dev_dbg(dev, "resume latency exceeded, %lld ns\n",
1032 elapsed_ns);
1033 genpd->gd->max_off_time_changed = true;
1034 td->constraint_changed = true;
1035 }
1036 }
1037
1038 return 0;
1039
1040err_stop:
1041 genpd_stop_dev(genpd, dev);
1042err_poweroff:
1043 if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
1044 genpd_lock(genpd);
1045 genpd_power_off(genpd, true, 0);
1046 gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
1047 genpd_unlock(genpd);
1048 }
1049
1050 return ret;
1051}
1052
1053static bool pd_ignore_unused;
1054static int __init pd_ignore_unused_setup(char *__unused)
1055{
1056 pd_ignore_unused = true;
1057 return 1;
1058}
1059__setup("pd_ignore_unused", pd_ignore_unused_setup);
1060
1061/**
1062 * genpd_power_off_unused - Power off all PM domains with no devices in use.
1063 */
1064static int __init genpd_power_off_unused(void)
1065{
1066 struct generic_pm_domain *genpd;
1067
1068 if (pd_ignore_unused) {
1069 pr_warn("genpd: Not disabling unused power domains\n");
1070 return 0;
1071 }
1072
1073 mutex_lock(&gpd_list_lock);
1074
1075 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
1076 genpd_queue_power_off_work(genpd);
1077
1078 mutex_unlock(&gpd_list_lock);
1079
1080 return 0;
1081}
1082late_initcall(genpd_power_off_unused);
1083
1084#ifdef CONFIG_PM_SLEEP
1085
1086/**
1087 * genpd_sync_power_off - Synchronously power off a PM domain and its parents.
1088 * @genpd: PM domain to power off, if possible.
1089 * @use_lock: use the lock.
1090 * @depth: nesting count for lockdep.
1091 *
1092 * Check if the given PM domain can be powered off (during system suspend or
1093 * hibernation) and do that if so. Also, in that case propagate to its parents.
1094 *
1095 * This function is only called in "noirq" and "syscore" stages of system power
1096 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1097 * these cases the lock must be held.
1098 */
1099static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
1100 unsigned int depth)
1101{
1102 struct gpd_link *link;
1103
1104 if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
1105 return;
1106
1107 if (genpd->suspended_count != genpd->device_count
1108 || atomic_read(&genpd->sd_count) > 0)
1109 return;
1110
1111 /* Check that the children are in their deepest (powered-off) state. */
1112 list_for_each_entry(link, &genpd->parent_links, parent_node) {
1113 struct generic_pm_domain *child = link->child;
1114 if (child->state_idx < child->state_count - 1)
1115 return;
1116 }
1117
1118 /* Choose the deepest state when suspending */
1119 genpd->state_idx = genpd->state_count - 1;
1120 if (_genpd_power_off(genpd, false))
1121 return;
1122
1123 genpd->status = GENPD_STATE_OFF;
1124
1125 list_for_each_entry(link, &genpd->child_links, child_node) {
1126 genpd_sd_counter_dec(link->parent);
1127
1128 if (use_lock)
1129 genpd_lock_nested(link->parent, depth + 1);
1130
1131 genpd_sync_power_off(link->parent, use_lock, depth + 1);
1132
1133 if (use_lock)
1134 genpd_unlock(link->parent);
1135 }
1136}
1137
1138/**
1139 * genpd_sync_power_on - Synchronously power on a PM domain and its parents.
1140 * @genpd: PM domain to power on.
1141 * @use_lock: use the lock.
1142 * @depth: nesting count for lockdep.
1143 *
1144 * This function is only called in "noirq" and "syscore" stages of system power
1145 * transitions. The "noirq" callbacks may be executed asynchronously, thus in
1146 * these cases the lock must be held.
1147 */
1148static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
1149 unsigned int depth)
1150{
1151 struct gpd_link *link;
1152
1153 if (genpd_status_on(genpd))
1154 return;
1155
1156 list_for_each_entry(link, &genpd->child_links, child_node) {
1157 genpd_sd_counter_inc(link->parent);
1158
1159 if (use_lock)
1160 genpd_lock_nested(link->parent, depth + 1);
1161
1162 genpd_sync_power_on(link->parent, use_lock, depth + 1);
1163
1164 if (use_lock)
1165 genpd_unlock(link->parent);
1166 }
1167
1168 _genpd_power_on(genpd, false);
1169 genpd->status = GENPD_STATE_ON;
1170}
1171
1172/**
1173 * genpd_prepare - Start power transition of a device in a PM domain.
1174 * @dev: Device to start the transition of.
1175 *
1176 * Start a power transition of a device (during a system-wide power transition)
1177 * under the assumption that its pm_domain field points to the domain member of
1178 * an object of type struct generic_pm_domain representing a PM domain
1179 * consisting of I/O devices.
1180 */
1181static int genpd_prepare(struct device *dev)
1182{
1183 struct generic_pm_domain *genpd;
1184 int ret;
1185
1186 dev_dbg(dev, "%s()\n", __func__);
1187
1188 genpd = dev_to_genpd(dev);
1189 if (IS_ERR(genpd))
1190 return -EINVAL;
1191
1192 genpd_lock(genpd);
1193
1194 if (genpd->prepared_count++ == 0)
1195 genpd->suspended_count = 0;
1196
1197 genpd_unlock(genpd);
1198
1199 ret = pm_generic_prepare(dev);
1200 if (ret < 0) {
1201 genpd_lock(genpd);
1202
1203 genpd->prepared_count--;
1204
1205 genpd_unlock(genpd);
1206 }
1207
1208 /* Never return 1, as genpd don't cope with the direct_complete path. */
1209 return ret >= 0 ? 0 : ret;
1210}
1211
1212/**
1213 * genpd_finish_suspend - Completion of suspend or hibernation of device in an
1214 * I/O pm domain.
1215 * @dev: Device to suspend.
1216 * @suspend_noirq: Generic suspend_noirq callback.
1217 * @resume_noirq: Generic resume_noirq callback.
1218 *
1219 * Stop the device and remove power from the domain if all devices in it have
1220 * been stopped.
1221 */
1222static int genpd_finish_suspend(struct device *dev,
1223 int (*suspend_noirq)(struct device *dev),
1224 int (*resume_noirq)(struct device *dev))
1225{
1226 struct generic_pm_domain *genpd;
1227 int ret = 0;
1228
1229 genpd = dev_to_genpd(dev);
1230 if (IS_ERR(genpd))
1231 return -EINVAL;
1232
1233 ret = suspend_noirq(dev);
1234 if (ret)
1235 return ret;
1236
1237 if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1238 return 0;
1239
1240 if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1241 !pm_runtime_status_suspended(dev)) {
1242 ret = genpd_stop_dev(genpd, dev);
1243 if (ret) {
1244 resume_noirq(dev);
1245 return ret;
1246 }
1247 }
1248
1249 genpd_lock(genpd);
1250 genpd->suspended_count++;
1251 genpd_sync_power_off(genpd, true, 0);
1252 genpd_unlock(genpd);
1253
1254 return 0;
1255}
1256
1257/**
1258 * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1259 * @dev: Device to suspend.
1260 *
1261 * Stop the device and remove power from the domain if all devices in it have
1262 * been stopped.
1263 */
1264static int genpd_suspend_noirq(struct device *dev)
1265{
1266 dev_dbg(dev, "%s()\n", __func__);
1267
1268 return genpd_finish_suspend(dev,
1269 pm_generic_suspend_noirq,
1270 pm_generic_resume_noirq);
1271}
1272
1273/**
1274 * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
1275 * @dev: Device to resume.
1276 * @resume_noirq: Generic resume_noirq callback.
1277 *
1278 * Restore power to the device's PM domain, if necessary, and start the device.
1279 */
1280static int genpd_finish_resume(struct device *dev,
1281 int (*resume_noirq)(struct device *dev))
1282{
1283 struct generic_pm_domain *genpd;
1284 int ret;
1285
1286 dev_dbg(dev, "%s()\n", __func__);
1287
1288 genpd = dev_to_genpd(dev);
1289 if (IS_ERR(genpd))
1290 return -EINVAL;
1291
1292 if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
1293 return resume_noirq(dev);
1294
1295 genpd_lock(genpd);
1296 genpd_sync_power_on(genpd, true, 0);
1297 genpd->suspended_count--;
1298 genpd_unlock(genpd);
1299
1300 if (genpd->dev_ops.stop && genpd->dev_ops.start &&
1301 !pm_runtime_status_suspended(dev)) {
1302 ret = genpd_start_dev(genpd, dev);
1303 if (ret)
1304 return ret;
1305 }
1306
1307 return pm_generic_resume_noirq(dev);
1308}
1309
1310/**
1311 * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1312 * @dev: Device to resume.
1313 *
1314 * Restore power to the device's PM domain, if necessary, and start the device.
1315 */
1316static int genpd_resume_noirq(struct device *dev)
1317{
1318 dev_dbg(dev, "%s()\n", __func__);
1319
1320 return genpd_finish_resume(dev, pm_generic_resume_noirq);
1321}
1322
1323/**
1324 * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1325 * @dev: Device to freeze.
1326 *
1327 * Carry out a late freeze of a device under the assumption that its
1328 * pm_domain field points to the domain member of an object of type
1329 * struct generic_pm_domain representing a power domain consisting of I/O
1330 * devices.
1331 */
1332static int genpd_freeze_noirq(struct device *dev)
1333{
1334 dev_dbg(dev, "%s()\n", __func__);
1335
1336 return genpd_finish_suspend(dev,
1337 pm_generic_freeze_noirq,
1338 pm_generic_thaw_noirq);
1339}
1340
1341/**
1342 * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1343 * @dev: Device to thaw.
1344 *
1345 * Start the device, unless power has been removed from the domain already
1346 * before the system transition.
1347 */
1348static int genpd_thaw_noirq(struct device *dev)
1349{
1350 dev_dbg(dev, "%s()\n", __func__);
1351
1352 return genpd_finish_resume(dev, pm_generic_thaw_noirq);
1353}
1354
1355/**
1356 * genpd_poweroff_noirq - Completion of hibernation of device in an
1357 * I/O PM domain.
1358 * @dev: Device to poweroff.
1359 *
1360 * Stop the device and remove power from the domain if all devices in it have
1361 * been stopped.
1362 */
1363static int genpd_poweroff_noirq(struct device *dev)
1364{
1365 dev_dbg(dev, "%s()\n", __func__);
1366
1367 return genpd_finish_suspend(dev,
1368 pm_generic_poweroff_noirq,
1369 pm_generic_restore_noirq);
1370}
1371
1372/**
1373 * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1374 * @dev: Device to resume.
1375 *
1376 * Make sure the domain will be in the same power state as before the
1377 * hibernation the system is resuming from and start the device if necessary.
1378 */
1379static int genpd_restore_noirq(struct device *dev)
1380{
1381 dev_dbg(dev, "%s()\n", __func__);
1382
1383 return genpd_finish_resume(dev, pm_generic_restore_noirq);
1384}
1385
1386/**
1387 * genpd_complete - Complete power transition of a device in a power domain.
1388 * @dev: Device to complete the transition of.
1389 *
1390 * Complete a power transition of a device (during a system-wide power
1391 * transition) under the assumption that its pm_domain field points to the
1392 * domain member of an object of type struct generic_pm_domain representing
1393 * a power domain consisting of I/O devices.
1394 */
1395static void genpd_complete(struct device *dev)
1396{
1397 struct generic_pm_domain *genpd;
1398
1399 dev_dbg(dev, "%s()\n", __func__);
1400
1401 genpd = dev_to_genpd(dev);
1402 if (IS_ERR(genpd))
1403 return;
1404
1405 pm_generic_complete(dev);
1406
1407 genpd_lock(genpd);
1408
1409 genpd->prepared_count--;
1410 if (!genpd->prepared_count)
1411 genpd_queue_power_off_work(genpd);
1412
1413 genpd_unlock(genpd);
1414}
1415
1416static void genpd_switch_state(struct device *dev, bool suspend)
1417{
1418 struct generic_pm_domain *genpd;
1419 bool use_lock;
1420
1421 genpd = dev_to_genpd_safe(dev);
1422 if (!genpd)
1423 return;
1424
1425 use_lock = genpd_is_irq_safe(genpd);
1426
1427 if (use_lock)
1428 genpd_lock(genpd);
1429
1430 if (suspend) {
1431 genpd->suspended_count++;
1432 genpd_sync_power_off(genpd, use_lock, 0);
1433 } else {
1434 genpd_sync_power_on(genpd, use_lock, 0);
1435 genpd->suspended_count--;
1436 }
1437
1438 if (use_lock)
1439 genpd_unlock(genpd);
1440}
1441
1442/**
1443 * dev_pm_genpd_suspend - Synchronously try to suspend the genpd for @dev
1444 * @dev: The device that is attached to the genpd, that can be suspended.
1445 *
1446 * This routine should typically be called for a device that needs to be
1447 * suspended during the syscore suspend phase. It may also be called during
1448 * suspend-to-idle to suspend a corresponding CPU device that is attached to a
1449 * genpd.
1450 */
1451void dev_pm_genpd_suspend(struct device *dev)
1452{
1453 genpd_switch_state(dev, true);
1454}
1455EXPORT_SYMBOL_GPL(dev_pm_genpd_suspend);
1456
1457/**
1458 * dev_pm_genpd_resume - Synchronously try to resume the genpd for @dev
1459 * @dev: The device that is attached to the genpd, which needs to be resumed.
1460 *
1461 * This routine should typically be called for a device that needs to be resumed
1462 * during the syscore resume phase. It may also be called during suspend-to-idle
1463 * to resume a corresponding CPU device that is attached to a genpd.
1464 */
1465void dev_pm_genpd_resume(struct device *dev)
1466{
1467 genpd_switch_state(dev, false);
1468}
1469EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
1470
1471#else /* !CONFIG_PM_SLEEP */
1472
1473#define genpd_prepare NULL
1474#define genpd_suspend_noirq NULL
1475#define genpd_resume_noirq NULL
1476#define genpd_freeze_noirq NULL
1477#define genpd_thaw_noirq NULL
1478#define genpd_poweroff_noirq NULL
1479#define genpd_restore_noirq NULL
1480#define genpd_complete NULL
1481
1482#endif /* CONFIG_PM_SLEEP */
1483
1484static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1485 bool has_governor)
1486{
1487 struct generic_pm_domain_data *gpd_data;
1488 struct gpd_timing_data *td;
1489 int ret;
1490
1491 ret = dev_pm_get_subsys_data(dev);
1492 if (ret)
1493 return ERR_PTR(ret);
1494
1495 gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1496 if (!gpd_data) {
1497 ret = -ENOMEM;
1498 goto err_put;
1499 }
1500
1501 gpd_data->base.dev = dev;
1502 gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1503
1504 /* Allocate data used by a governor. */
1505 if (has_governor) {
1506 td = kzalloc(sizeof(*td), GFP_KERNEL);
1507 if (!td) {
1508 ret = -ENOMEM;
1509 goto err_free;
1510 }
1511
1512 td->constraint_changed = true;
1513 td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
1514 td->next_wakeup = KTIME_MAX;
1515 gpd_data->td = td;
1516 }
1517
1518 spin_lock_irq(&dev->power.lock);
1519
1520 if (dev->power.subsys_data->domain_data)
1521 ret = -EINVAL;
1522 else
1523 dev->power.subsys_data->domain_data = &gpd_data->base;
1524
1525 spin_unlock_irq(&dev->power.lock);
1526
1527 if (ret)
1528 goto err_free;
1529
1530 return gpd_data;
1531
1532 err_free:
1533 kfree(gpd_data->td);
1534 kfree(gpd_data);
1535 err_put:
1536 dev_pm_put_subsys_data(dev);
1537 return ERR_PTR(ret);
1538}
1539
1540static void genpd_free_dev_data(struct device *dev,
1541 struct generic_pm_domain_data *gpd_data)
1542{
1543 spin_lock_irq(&dev->power.lock);
1544
1545 dev->power.subsys_data->domain_data = NULL;
1546
1547 spin_unlock_irq(&dev->power.lock);
1548
1549 kfree(gpd_data->td);
1550 kfree(gpd_data);
1551 dev_pm_put_subsys_data(dev);
1552}
1553
1554static void genpd_update_cpumask(struct generic_pm_domain *genpd,
1555 int cpu, bool set, unsigned int depth)
1556{
1557 struct gpd_link *link;
1558
1559 if (!genpd_is_cpu_domain(genpd))
1560 return;
1561
1562 list_for_each_entry(link, &genpd->child_links, child_node) {
1563 struct generic_pm_domain *parent = link->parent;
1564
1565 genpd_lock_nested(parent, depth + 1);
1566 genpd_update_cpumask(parent, cpu, set, depth + 1);
1567 genpd_unlock(parent);
1568 }
1569
1570 if (set)
1571 cpumask_set_cpu(cpu, genpd->cpus);
1572 else
1573 cpumask_clear_cpu(cpu, genpd->cpus);
1574}
1575
1576static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
1577{
1578 if (cpu >= 0)
1579 genpd_update_cpumask(genpd, cpu, true, 0);
1580}
1581
1582static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
1583{
1584 if (cpu >= 0)
1585 genpd_update_cpumask(genpd, cpu, false, 0);
1586}
1587
1588static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
1589{
1590 int cpu;
1591
1592 if (!genpd_is_cpu_domain(genpd))
1593 return -1;
1594
1595 for_each_possible_cpu(cpu) {
1596 if (get_cpu_device(cpu) == dev)
1597 return cpu;
1598 }
1599
1600 return -1;
1601}
1602
1603static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1604 struct device *base_dev)
1605{
1606 struct genpd_governor_data *gd = genpd->gd;
1607 struct generic_pm_domain_data *gpd_data;
1608 int ret;
1609
1610 dev_dbg(dev, "%s()\n", __func__);
1611
1612 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1613 return -EINVAL;
1614
1615 gpd_data = genpd_alloc_dev_data(dev, gd);
1616 if (IS_ERR(gpd_data))
1617 return PTR_ERR(gpd_data);
1618
1619 gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
1620
1621 ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1622 if (ret)
1623 goto out;
1624
1625 genpd_lock(genpd);
1626
1627 genpd_set_cpumask(genpd, gpd_data->cpu);
1628 dev_pm_domain_set(dev, &genpd->domain);
1629
1630 genpd->device_count++;
1631 if (gd)
1632 gd->max_off_time_changed = true;
1633
1634 list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1635
1636 genpd_unlock(genpd);
1637 out:
1638 if (ret)
1639 genpd_free_dev_data(dev, gpd_data);
1640 else
1641 dev_pm_qos_add_notifier(dev, &gpd_data->nb,
1642 DEV_PM_QOS_RESUME_LATENCY);
1643
1644 return ret;
1645}
1646
1647/**
1648 * pm_genpd_add_device - Add a device to an I/O PM domain.
1649 * @genpd: PM domain to add the device to.
1650 * @dev: Device to be added.
1651 */
1652int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
1653{
1654 int ret;
1655
1656 mutex_lock(&gpd_list_lock);
1657 ret = genpd_add_device(genpd, dev, dev);
1658 mutex_unlock(&gpd_list_lock);
1659
1660 return ret;
1661}
1662EXPORT_SYMBOL_GPL(pm_genpd_add_device);
1663
1664static int genpd_remove_device(struct generic_pm_domain *genpd,
1665 struct device *dev)
1666{
1667 struct generic_pm_domain_data *gpd_data;
1668 struct pm_domain_data *pdd;
1669 int ret = 0;
1670
1671 dev_dbg(dev, "%s()\n", __func__);
1672
1673 pdd = dev->power.subsys_data->domain_data;
1674 gpd_data = to_gpd_data(pdd);
1675 dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
1676 DEV_PM_QOS_RESUME_LATENCY);
1677
1678 genpd_lock(genpd);
1679
1680 if (genpd->prepared_count > 0) {
1681 ret = -EAGAIN;
1682 goto out;
1683 }
1684
1685 genpd->device_count--;
1686 if (genpd->gd)
1687 genpd->gd->max_off_time_changed = true;
1688
1689 genpd_clear_cpumask(genpd, gpd_data->cpu);
1690 dev_pm_domain_set(dev, NULL);
1691
1692 list_del_init(&pdd->list_node);
1693
1694 genpd_unlock(genpd);
1695
1696 if (genpd->detach_dev)
1697 genpd->detach_dev(genpd, dev);
1698
1699 genpd_free_dev_data(dev, gpd_data);
1700
1701 return 0;
1702
1703 out:
1704 genpd_unlock(genpd);
1705 dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
1706
1707 return ret;
1708}
1709
1710/**
1711 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1712 * @dev: Device to be removed.
1713 */
1714int pm_genpd_remove_device(struct device *dev)
1715{
1716 struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
1717
1718 if (!genpd)
1719 return -EINVAL;
1720
1721 return genpd_remove_device(genpd, dev);
1722}
1723EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1724
1725/**
1726 * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev
1727 *
1728 * @dev: Device that should be associated with the notifier
1729 * @nb: The notifier block to register
1730 *
1731 * Users may call this function to add a genpd power on/off notifier for an
1732 * attached @dev. Only one notifier per device is allowed. The notifier is
1733 * sent when genpd is powering on/off the PM domain.
1734 *
1735 * It is assumed that the user guarantee that the genpd wouldn't be detached
1736 * while this routine is getting called.
1737 *
1738 * Returns 0 on success and negative error values on failures.
1739 */
1740int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb)
1741{
1742 struct generic_pm_domain *genpd;
1743 struct generic_pm_domain_data *gpd_data;
1744 int ret;
1745
1746 genpd = dev_to_genpd_safe(dev);
1747 if (!genpd)
1748 return -ENODEV;
1749
1750 if (WARN_ON(!dev->power.subsys_data ||
1751 !dev->power.subsys_data->domain_data))
1752 return -EINVAL;
1753
1754 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1755 if (gpd_data->power_nb)
1756 return -EEXIST;
1757
1758 genpd_lock(genpd);
1759 ret = raw_notifier_chain_register(&genpd->power_notifiers, nb);
1760 genpd_unlock(genpd);
1761
1762 if (ret) {
1763 dev_warn(dev, "failed to add notifier for PM domain %s\n",
1764 genpd->name);
1765 return ret;
1766 }
1767
1768 gpd_data->power_nb = nb;
1769 return 0;
1770}
1771EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier);
1772
1773/**
1774 * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev
1775 *
1776 * @dev: Device that is associated with the notifier
1777 *
1778 * Users may call this function to remove a genpd power on/off notifier for an
1779 * attached @dev.
1780 *
1781 * It is assumed that the user guarantee that the genpd wouldn't be detached
1782 * while this routine is getting called.
1783 *
1784 * Returns 0 on success and negative error values on failures.
1785 */
1786int dev_pm_genpd_remove_notifier(struct device *dev)
1787{
1788 struct generic_pm_domain *genpd;
1789 struct generic_pm_domain_data *gpd_data;
1790 int ret;
1791
1792 genpd = dev_to_genpd_safe(dev);
1793 if (!genpd)
1794 return -ENODEV;
1795
1796 if (WARN_ON(!dev->power.subsys_data ||
1797 !dev->power.subsys_data->domain_data))
1798 return -EINVAL;
1799
1800 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1801 if (!gpd_data->power_nb)
1802 return -ENODEV;
1803
1804 genpd_lock(genpd);
1805 ret = raw_notifier_chain_unregister(&genpd->power_notifiers,
1806 gpd_data->power_nb);
1807 genpd_unlock(genpd);
1808
1809 if (ret) {
1810 dev_warn(dev, "failed to remove notifier for PM domain %s\n",
1811 genpd->name);
1812 return ret;
1813 }
1814
1815 gpd_data->power_nb = NULL;
1816 return 0;
1817}
1818EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier);
1819
1820static int genpd_add_subdomain(struct generic_pm_domain *genpd,
1821 struct generic_pm_domain *subdomain)
1822{
1823 struct gpd_link *link, *itr;
1824 int ret = 0;
1825
1826 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1827 || genpd == subdomain)
1828 return -EINVAL;
1829
1830 /*
1831 * If the domain can be powered on/off in an IRQ safe
1832 * context, ensure that the subdomain can also be
1833 * powered on/off in that context.
1834 */
1835 if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
1836 WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
1837 genpd->name, subdomain->name);
1838 return -EINVAL;
1839 }
1840
1841 link = kzalloc(sizeof(*link), GFP_KERNEL);
1842 if (!link)
1843 return -ENOMEM;
1844
1845 genpd_lock(subdomain);
1846 genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1847
1848 if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
1849 ret = -EINVAL;
1850 goto out;
1851 }
1852
1853 list_for_each_entry(itr, &genpd->parent_links, parent_node) {
1854 if (itr->child == subdomain && itr->parent == genpd) {
1855 ret = -EINVAL;
1856 goto out;
1857 }
1858 }
1859
1860 link->parent = genpd;
1861 list_add_tail(&link->parent_node, &genpd->parent_links);
1862 link->child = subdomain;
1863 list_add_tail(&link->child_node, &subdomain->child_links);
1864 if (genpd_status_on(subdomain))
1865 genpd_sd_counter_inc(genpd);
1866
1867 out:
1868 genpd_unlock(genpd);
1869 genpd_unlock(subdomain);
1870 if (ret)
1871 kfree(link);
1872 return ret;
1873}
1874
1875/**
1876 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1877 * @genpd: Leader PM domain to add the subdomain to.
1878 * @subdomain: Subdomain to be added.
1879 */
1880int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1881 struct generic_pm_domain *subdomain)
1882{
1883 int ret;
1884
1885 mutex_lock(&gpd_list_lock);
1886 ret = genpd_add_subdomain(genpd, subdomain);
1887 mutex_unlock(&gpd_list_lock);
1888
1889 return ret;
1890}
1891EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1892
1893/**
1894 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1895 * @genpd: Leader PM domain to remove the subdomain from.
1896 * @subdomain: Subdomain to be removed.
1897 */
1898int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1899 struct generic_pm_domain *subdomain)
1900{
1901 struct gpd_link *l, *link;
1902 int ret = -EINVAL;
1903
1904 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1905 return -EINVAL;
1906
1907 genpd_lock(subdomain);
1908 genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
1909
1910 if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {
1911 pr_warn("%s: unable to remove subdomain %s\n",
1912 genpd->name, subdomain->name);
1913 ret = -EBUSY;
1914 goto out;
1915 }
1916
1917 list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {
1918 if (link->child != subdomain)
1919 continue;
1920
1921 list_del(&link->parent_node);
1922 list_del(&link->child_node);
1923 kfree(link);
1924 if (genpd_status_on(subdomain))
1925 genpd_sd_counter_dec(genpd);
1926
1927 ret = 0;
1928 break;
1929 }
1930
1931out:
1932 genpd_unlock(genpd);
1933 genpd_unlock(subdomain);
1934
1935 return ret;
1936}
1937EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1938
1939static void genpd_free_default_power_state(struct genpd_power_state *states,
1940 unsigned int state_count)
1941{
1942 kfree(states);
1943}
1944
1945static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
1946{
1947 struct genpd_power_state *state;
1948
1949 state = kzalloc(sizeof(*state), GFP_KERNEL);
1950 if (!state)
1951 return -ENOMEM;
1952
1953 genpd->states = state;
1954 genpd->state_count = 1;
1955 genpd->free_states = genpd_free_default_power_state;
1956
1957 return 0;
1958}
1959
1960static int genpd_alloc_data(struct generic_pm_domain *genpd)
1961{
1962 struct genpd_governor_data *gd = NULL;
1963 int ret;
1964
1965 if (genpd_is_cpu_domain(genpd) &&
1966 !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
1967 return -ENOMEM;
1968
1969 if (genpd->gov) {
1970 gd = kzalloc(sizeof(*gd), GFP_KERNEL);
1971 if (!gd) {
1972 ret = -ENOMEM;
1973 goto free;
1974 }
1975
1976 gd->max_off_time_ns = -1;
1977 gd->max_off_time_changed = true;
1978 gd->next_wakeup = KTIME_MAX;
1979 gd->next_hrtimer = KTIME_MAX;
1980 }
1981
1982 /* Use only one "off" state if there were no states declared */
1983 if (genpd->state_count == 0) {
1984 ret = genpd_set_default_power_state(genpd);
1985 if (ret)
1986 goto free;
1987 }
1988
1989 genpd->gd = gd;
1990 return 0;
1991
1992free:
1993 if (genpd_is_cpu_domain(genpd))
1994 free_cpumask_var(genpd->cpus);
1995 kfree(gd);
1996 return ret;
1997}
1998
1999static void genpd_free_data(struct generic_pm_domain *genpd)
2000{
2001 if (genpd_is_cpu_domain(genpd))
2002 free_cpumask_var(genpd->cpus);
2003 if (genpd->free_states)
2004 genpd->free_states(genpd->states, genpd->state_count);
2005 kfree(genpd->gd);
2006}
2007
2008static void genpd_lock_init(struct generic_pm_domain *genpd)
2009{
2010 if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
2011 spin_lock_init(&genpd->slock);
2012 genpd->lock_ops = &genpd_spin_ops;
2013 } else {
2014 mutex_init(&genpd->mlock);
2015 genpd->lock_ops = &genpd_mtx_ops;
2016 }
2017}
2018
2019/**
2020 * pm_genpd_init - Initialize a generic I/O PM domain object.
2021 * @genpd: PM domain object to initialize.
2022 * @gov: PM domain governor to associate with the domain (may be NULL).
2023 * @is_off: Initial value of the domain's power_is_off field.
2024 *
2025 * Returns 0 on successful initialization, else a negative error code.
2026 */
2027int pm_genpd_init(struct generic_pm_domain *genpd,
2028 struct dev_power_governor *gov, bool is_off)
2029{
2030 int ret;
2031
2032 if (IS_ERR_OR_NULL(genpd))
2033 return -EINVAL;
2034
2035 INIT_LIST_HEAD(&genpd->parent_links);
2036 INIT_LIST_HEAD(&genpd->child_links);
2037 INIT_LIST_HEAD(&genpd->dev_list);
2038 RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers);
2039 genpd_lock_init(genpd);
2040 genpd->gov = gov;
2041 INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2042 atomic_set(&genpd->sd_count, 0);
2043 genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
2044 genpd->device_count = 0;
2045 genpd->provider = NULL;
2046 genpd->has_provider = false;
2047 genpd->accounting_time = ktime_get_mono_fast_ns();
2048 genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
2049 genpd->domain.ops.runtime_resume = genpd_runtime_resume;
2050 genpd->domain.ops.prepare = genpd_prepare;
2051 genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
2052 genpd->domain.ops.resume_noirq = genpd_resume_noirq;
2053 genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
2054 genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
2055 genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
2056 genpd->domain.ops.restore_noirq = genpd_restore_noirq;
2057 genpd->domain.ops.complete = genpd_complete;
2058 genpd->domain.start = genpd_dev_pm_start;
2059
2060 if (genpd->flags & GENPD_FLAG_PM_CLK) {
2061 genpd->dev_ops.stop = pm_clk_suspend;
2062 genpd->dev_ops.start = pm_clk_resume;
2063 }
2064
2065 /* The always-on governor works better with the corresponding flag. */
2066 if (gov == &pm_domain_always_on_gov)
2067 genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
2068
2069 /* Always-on domains must be powered on at initialization. */
2070 if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
2071 !genpd_status_on(genpd)) {
2072 pr_err("always-on PM domain %s is not on\n", genpd->name);
2073 return -EINVAL;
2074 }
2075
2076 /* Multiple states but no governor doesn't make sense. */
2077 if (!gov && genpd->state_count > 1)
2078 pr_warn("%s: no governor for states\n", genpd->name);
2079
2080 ret = genpd_alloc_data(genpd);
2081 if (ret)
2082 return ret;
2083
2084 device_initialize(&genpd->dev);
2085 dev_set_name(&genpd->dev, "%s", genpd->name);
2086
2087 mutex_lock(&gpd_list_lock);
2088 list_add(&genpd->gpd_list_node, &gpd_list);
2089 mutex_unlock(&gpd_list_lock);
2090 genpd_debug_add(genpd);
2091
2092 return 0;
2093}
2094EXPORT_SYMBOL_GPL(pm_genpd_init);
2095
2096static int genpd_remove(struct generic_pm_domain *genpd)
2097{
2098 struct gpd_link *l, *link;
2099
2100 if (IS_ERR_OR_NULL(genpd))
2101 return -EINVAL;
2102
2103 genpd_lock(genpd);
2104
2105 if (genpd->has_provider) {
2106 genpd_unlock(genpd);
2107 pr_err("Provider present, unable to remove %s\n", genpd->name);
2108 return -EBUSY;
2109 }
2110
2111 if (!list_empty(&genpd->parent_links) || genpd->device_count) {
2112 genpd_unlock(genpd);
2113 pr_err("%s: unable to remove %s\n", __func__, genpd->name);
2114 return -EBUSY;
2115 }
2116
2117 list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {
2118 list_del(&link->parent_node);
2119 list_del(&link->child_node);
2120 kfree(link);
2121 }
2122
2123 list_del(&genpd->gpd_list_node);
2124 genpd_unlock(genpd);
2125 genpd_debug_remove(genpd);
2126 cancel_work_sync(&genpd->power_off_work);
2127 genpd_free_data(genpd);
2128
2129 pr_debug("%s: removed %s\n", __func__, genpd->name);
2130
2131 return 0;
2132}
2133
2134/**
2135 * pm_genpd_remove - Remove a generic I/O PM domain
2136 * @genpd: Pointer to PM domain that is to be removed.
2137 *
2138 * To remove the PM domain, this function:
2139 * - Removes the PM domain as a subdomain to any parent domains,
2140 * if it was added.
2141 * - Removes the PM domain from the list of registered PM domains.
2142 *
2143 * The PM domain will only be removed, if the associated provider has
2144 * been removed, it is not a parent to any other PM domain and has no
2145 * devices associated with it.
2146 */
2147int pm_genpd_remove(struct generic_pm_domain *genpd)
2148{
2149 int ret;
2150
2151 mutex_lock(&gpd_list_lock);
2152 ret = genpd_remove(genpd);
2153 mutex_unlock(&gpd_list_lock);
2154
2155 return ret;
2156}
2157EXPORT_SYMBOL_GPL(pm_genpd_remove);
2158
2159#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
2160
2161/*
2162 * Device Tree based PM domain providers.
2163 *
2164 * The code below implements generic device tree based PM domain providers that
2165 * bind device tree nodes with generic PM domains registered in the system.
2166 *
2167 * Any driver that registers generic PM domains and needs to support binding of
2168 * devices to these domains is supposed to register a PM domain provider, which
2169 * maps a PM domain specifier retrieved from the device tree to a PM domain.
2170 *
2171 * Two simple mapping functions have been provided for convenience:
2172 * - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
2173 * - genpd_xlate_onecell() for mapping of multiple PM domains per node by
2174 * index.
2175 */
2176
2177/**
2178 * struct of_genpd_provider - PM domain provider registration structure
2179 * @link: Entry in global list of PM domain providers
2180 * @node: Pointer to device tree node of PM domain provider
2181 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
2182 * into a PM domain.
2183 * @data: context pointer to be passed into @xlate callback
2184 */
2185struct of_genpd_provider {
2186 struct list_head link;
2187 struct device_node *node;
2188 genpd_xlate_t xlate;
2189 void *data;
2190};
2191
2192/* List of registered PM domain providers. */
2193static LIST_HEAD(of_genpd_providers);
2194/* Mutex to protect the list above. */
2195static DEFINE_MUTEX(of_genpd_mutex);
2196
2197/**
2198 * genpd_xlate_simple() - Xlate function for direct node-domain mapping
2199 * @genpdspec: OF phandle args to map into a PM domain
2200 * @data: xlate function private data - pointer to struct generic_pm_domain
2201 *
2202 * This is a generic xlate function that can be used to model PM domains that
2203 * have their own device tree nodes. The private data of xlate function needs
2204 * to be a valid pointer to struct generic_pm_domain.
2205 */
2206static struct generic_pm_domain *genpd_xlate_simple(
2207 struct of_phandle_args *genpdspec,
2208 void *data)
2209{
2210 return data;
2211}
2212
2213/**
2214 * genpd_xlate_onecell() - Xlate function using a single index.
2215 * @genpdspec: OF phandle args to map into a PM domain
2216 * @data: xlate function private data - pointer to struct genpd_onecell_data
2217 *
2218 * This is a generic xlate function that can be used to model simple PM domain
2219 * controllers that have one device tree node and provide multiple PM domains.
2220 * A single cell is used as an index into an array of PM domains specified in
2221 * the genpd_onecell_data struct when registering the provider.
2222 */
2223static struct generic_pm_domain *genpd_xlate_onecell(
2224 struct of_phandle_args *genpdspec,
2225 void *data)
2226{
2227 struct genpd_onecell_data *genpd_data = data;
2228 unsigned int idx = genpdspec->args[0];
2229
2230 if (genpdspec->args_count != 1)
2231 return ERR_PTR(-EINVAL);
2232
2233 if (idx >= genpd_data->num_domains) {
2234 pr_err("%s: invalid domain index %u\n", __func__, idx);
2235 return ERR_PTR(-EINVAL);
2236 }
2237
2238 if (!genpd_data->domains[idx])
2239 return ERR_PTR(-ENOENT);
2240
2241 return genpd_data->domains[idx];
2242}
2243
2244/**
2245 * genpd_add_provider() - Register a PM domain provider for a node
2246 * @np: Device node pointer associated with the PM domain provider.
2247 * @xlate: Callback for decoding PM domain from phandle arguments.
2248 * @data: Context pointer for @xlate callback.
2249 */
2250static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
2251 void *data)
2252{
2253 struct of_genpd_provider *cp;
2254
2255 cp = kzalloc(sizeof(*cp), GFP_KERNEL);
2256 if (!cp)
2257 return -ENOMEM;
2258
2259 cp->node = of_node_get(np);
2260 cp->data = data;
2261 cp->xlate = xlate;
2262 fwnode_dev_initialized(&np->fwnode, true);
2263
2264 mutex_lock(&of_genpd_mutex);
2265 list_add(&cp->link, &of_genpd_providers);
2266 mutex_unlock(&of_genpd_mutex);
2267 pr_debug("Added domain provider from %pOF\n", np);
2268
2269 return 0;
2270}
2271
2272static bool genpd_present(const struct generic_pm_domain *genpd)
2273{
2274 bool ret = false;
2275 const struct generic_pm_domain *gpd;
2276
2277 mutex_lock(&gpd_list_lock);
2278 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2279 if (gpd == genpd) {
2280 ret = true;
2281 break;
2282 }
2283 }
2284 mutex_unlock(&gpd_list_lock);
2285
2286 return ret;
2287}
2288
2289/**
2290 * of_genpd_add_provider_simple() - Register a simple PM domain provider
2291 * @np: Device node pointer associated with the PM domain provider.
2292 * @genpd: Pointer to PM domain associated with the PM domain provider.
2293 */
2294int of_genpd_add_provider_simple(struct device_node *np,
2295 struct generic_pm_domain *genpd)
2296{
2297 int ret;
2298
2299 if (!np || !genpd)
2300 return -EINVAL;
2301
2302 if (!genpd_present(genpd))
2303 return -EINVAL;
2304
2305 genpd->dev.of_node = np;
2306
2307 /* Parse genpd OPP table */
2308 if (genpd->set_performance_state) {
2309 ret = dev_pm_opp_of_add_table(&genpd->dev);
2310 if (ret)
2311 return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
2312
2313 /*
2314 * Save table for faster processing while setting performance
2315 * state.
2316 */
2317 genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2318 WARN_ON(IS_ERR(genpd->opp_table));
2319 }
2320
2321 ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
2322 if (ret) {
2323 if (genpd->set_performance_state) {
2324 dev_pm_opp_put_opp_table(genpd->opp_table);
2325 dev_pm_opp_of_remove_table(&genpd->dev);
2326 }
2327
2328 return ret;
2329 }
2330
2331 genpd->provider = &np->fwnode;
2332 genpd->has_provider = true;
2333
2334 return 0;
2335}
2336EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
2337
2338/**
2339 * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
2340 * @np: Device node pointer associated with the PM domain provider.
2341 * @data: Pointer to the data associated with the PM domain provider.
2342 */
2343int of_genpd_add_provider_onecell(struct device_node *np,
2344 struct genpd_onecell_data *data)
2345{
2346 struct generic_pm_domain *genpd;
2347 unsigned int i;
2348 int ret = -EINVAL;
2349
2350 if (!np || !data)
2351 return -EINVAL;
2352
2353 if (!data->xlate)
2354 data->xlate = genpd_xlate_onecell;
2355
2356 for (i = 0; i < data->num_domains; i++) {
2357 genpd = data->domains[i];
2358
2359 if (!genpd)
2360 continue;
2361 if (!genpd_present(genpd))
2362 goto error;
2363
2364 genpd->dev.of_node = np;
2365
2366 /* Parse genpd OPP table */
2367 if (genpd->set_performance_state) {
2368 ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
2369 if (ret) {
2370 dev_err_probe(&genpd->dev, ret,
2371 "Failed to add OPP table for index %d\n", i);
2372 goto error;
2373 }
2374
2375 /*
2376 * Save table for faster processing while setting
2377 * performance state.
2378 */
2379 genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
2380 WARN_ON(IS_ERR(genpd->opp_table));
2381 }
2382
2383 genpd->provider = &np->fwnode;
2384 genpd->has_provider = true;
2385 }
2386
2387 ret = genpd_add_provider(np, data->xlate, data);
2388 if (ret < 0)
2389 goto error;
2390
2391 return 0;
2392
2393error:
2394 while (i--) {
2395 genpd = data->domains[i];
2396
2397 if (!genpd)
2398 continue;
2399
2400 genpd->provider = NULL;
2401 genpd->has_provider = false;
2402
2403 if (genpd->set_performance_state) {
2404 dev_pm_opp_put_opp_table(genpd->opp_table);
2405 dev_pm_opp_of_remove_table(&genpd->dev);
2406 }
2407 }
2408
2409 return ret;
2410}
2411EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
2412
2413/**
2414 * of_genpd_del_provider() - Remove a previously registered PM domain provider
2415 * @np: Device node pointer associated with the PM domain provider
2416 */
2417void of_genpd_del_provider(struct device_node *np)
2418{
2419 struct of_genpd_provider *cp, *tmp;
2420 struct generic_pm_domain *gpd;
2421
2422 mutex_lock(&gpd_list_lock);
2423 mutex_lock(&of_genpd_mutex);
2424 list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
2425 if (cp->node == np) {
2426 /*
2427 * For each PM domain associated with the
2428 * provider, set the 'has_provider' to false
2429 * so that the PM domain can be safely removed.
2430 */
2431 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
2432 if (gpd->provider == &np->fwnode) {
2433 gpd->has_provider = false;
2434
2435 if (!gpd->set_performance_state)
2436 continue;
2437
2438 dev_pm_opp_put_opp_table(gpd->opp_table);
2439 dev_pm_opp_of_remove_table(&gpd->dev);
2440 }
2441 }
2442
2443 fwnode_dev_initialized(&cp->node->fwnode, false);
2444 list_del(&cp->link);
2445 of_node_put(cp->node);
2446 kfree(cp);
2447 break;
2448 }
2449 }
2450 mutex_unlock(&of_genpd_mutex);
2451 mutex_unlock(&gpd_list_lock);
2452}
2453EXPORT_SYMBOL_GPL(of_genpd_del_provider);
2454
2455/**
2456 * genpd_get_from_provider() - Look-up PM domain
2457 * @genpdspec: OF phandle args to use for look-up
2458 *
2459 * Looks for a PM domain provider under the node specified by @genpdspec and if
2460 * found, uses xlate function of the provider to map phandle args to a PM
2461 * domain.
2462 *
2463 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
2464 * on failure.
2465 */
2466static struct generic_pm_domain *genpd_get_from_provider(
2467 struct of_phandle_args *genpdspec)
2468{
2469 struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
2470 struct of_genpd_provider *provider;
2471
2472 if (!genpdspec)
2473 return ERR_PTR(-EINVAL);
2474
2475 mutex_lock(&of_genpd_mutex);
2476
2477 /* Check if we have such a provider in our array */
2478 list_for_each_entry(provider, &of_genpd_providers, link) {
2479 if (provider->node == genpdspec->np)
2480 genpd = provider->xlate(genpdspec, provider->data);
2481 if (!IS_ERR(genpd))
2482 break;
2483 }
2484
2485 mutex_unlock(&of_genpd_mutex);
2486
2487 return genpd;
2488}
2489
2490/**
2491 * of_genpd_add_device() - Add a device to an I/O PM domain
2492 * @genpdspec: OF phandle args to use for look-up PM domain
2493 * @dev: Device to be added.
2494 *
2495 * Looks-up an I/O PM domain based upon phandle args provided and adds
2496 * the device to the PM domain. Returns a negative error code on failure.
2497 */
2498int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
2499{
2500 struct generic_pm_domain *genpd;
2501 int ret;
2502
2503 mutex_lock(&gpd_list_lock);
2504
2505 genpd = genpd_get_from_provider(genpdspec);
2506 if (IS_ERR(genpd)) {
2507 ret = PTR_ERR(genpd);
2508 goto out;
2509 }
2510
2511 ret = genpd_add_device(genpd, dev, dev);
2512
2513out:
2514 mutex_unlock(&gpd_list_lock);
2515
2516 return ret;
2517}
2518EXPORT_SYMBOL_GPL(of_genpd_add_device);
2519
2520/**
2521 * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
2522 * @parent_spec: OF phandle args to use for parent PM domain look-up
2523 * @subdomain_spec: OF phandle args to use for subdomain look-up
2524 *
2525 * Looks-up a parent PM domain and subdomain based upon phandle args
2526 * provided and adds the subdomain to the parent PM domain. Returns a
2527 * negative error code on failure.
2528 */
2529int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
2530 struct of_phandle_args *subdomain_spec)
2531{
2532 struct generic_pm_domain *parent, *subdomain;
2533 int ret;
2534
2535 mutex_lock(&gpd_list_lock);
2536
2537 parent = genpd_get_from_provider(parent_spec);
2538 if (IS_ERR(parent)) {
2539 ret = PTR_ERR(parent);
2540 goto out;
2541 }
2542
2543 subdomain = genpd_get_from_provider(subdomain_spec);
2544 if (IS_ERR(subdomain)) {
2545 ret = PTR_ERR(subdomain);
2546 goto out;
2547 }
2548
2549 ret = genpd_add_subdomain(parent, subdomain);
2550
2551out:
2552 mutex_unlock(&gpd_list_lock);
2553
2554 return ret == -ENOENT ? -EPROBE_DEFER : ret;
2555}
2556EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
2557
2558/**
2559 * of_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
2560 * @parent_spec: OF phandle args to use for parent PM domain look-up
2561 * @subdomain_spec: OF phandle args to use for subdomain look-up
2562 *
2563 * Looks-up a parent PM domain and subdomain based upon phandle args
2564 * provided and removes the subdomain from the parent PM domain. Returns a
2565 * negative error code on failure.
2566 */
2567int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
2568 struct of_phandle_args *subdomain_spec)
2569{
2570 struct generic_pm_domain *parent, *subdomain;
2571 int ret;
2572
2573 mutex_lock(&gpd_list_lock);
2574
2575 parent = genpd_get_from_provider(parent_spec);
2576 if (IS_ERR(parent)) {
2577 ret = PTR_ERR(parent);
2578 goto out;
2579 }
2580
2581 subdomain = genpd_get_from_provider(subdomain_spec);
2582 if (IS_ERR(subdomain)) {
2583 ret = PTR_ERR(subdomain);
2584 goto out;
2585 }
2586
2587 ret = pm_genpd_remove_subdomain(parent, subdomain);
2588
2589out:
2590 mutex_unlock(&gpd_list_lock);
2591
2592 return ret;
2593}
2594EXPORT_SYMBOL_GPL(of_genpd_remove_subdomain);
2595
2596/**
2597 * of_genpd_remove_last - Remove the last PM domain registered for a provider
2598 * @np: Pointer to device node associated with provider
2599 *
2600 * Find the last PM domain that was added by a particular provider and
2601 * remove this PM domain from the list of PM domains. The provider is
2602 * identified by the 'provider' device structure that is passed. The PM
2603 * domain will only be removed, if the provider associated with domain
2604 * has been removed.
2605 *
2606 * Returns a valid pointer to struct generic_pm_domain on success or
2607 * ERR_PTR() on failure.
2608 */
2609struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
2610{
2611 struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
2612 int ret;
2613
2614 if (IS_ERR_OR_NULL(np))
2615 return ERR_PTR(-EINVAL);
2616
2617 mutex_lock(&gpd_list_lock);
2618 list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
2619 if (gpd->provider == &np->fwnode) {
2620 ret = genpd_remove(gpd);
2621 genpd = ret ? ERR_PTR(ret) : gpd;
2622 break;
2623 }
2624 }
2625 mutex_unlock(&gpd_list_lock);
2626
2627 return genpd;
2628}
2629EXPORT_SYMBOL_GPL(of_genpd_remove_last);
2630
2631static void genpd_release_dev(struct device *dev)
2632{
2633 of_node_put(dev->of_node);
2634 kfree(dev);
2635}
2636
2637static struct bus_type genpd_bus_type = {
2638 .name = "genpd",
2639};
2640
2641/**
2642 * genpd_dev_pm_detach - Detach a device from its PM domain.
2643 * @dev: Device to detach.
2644 * @power_off: Currently not used
2645 *
2646 * Try to locate a corresponding generic PM domain, which the device was
2647 * attached to previously. If such is found, the device is detached from it.
2648 */
2649static void genpd_dev_pm_detach(struct device *dev, bool power_off)
2650{
2651 struct generic_pm_domain *pd;
2652 unsigned int i;
2653 int ret = 0;
2654
2655 pd = dev_to_genpd(dev);
2656 if (IS_ERR(pd))
2657 return;
2658
2659 dev_dbg(dev, "removing from PM domain %s\n", pd->name);
2660
2661 /* Drop the default performance state */
2662 if (dev_gpd_data(dev)->default_pstate) {
2663 dev_pm_genpd_set_performance_state(dev, 0);
2664 dev_gpd_data(dev)->default_pstate = 0;
2665 }
2666
2667 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2668 ret = genpd_remove_device(pd, dev);
2669 if (ret != -EAGAIN)
2670 break;
2671
2672 mdelay(i);
2673 cond_resched();
2674 }
2675
2676 if (ret < 0) {
2677 dev_err(dev, "failed to remove from PM domain %s: %d",
2678 pd->name, ret);
2679 return;
2680 }
2681
2682 /* Check if PM domain can be powered off after removing this device. */
2683 genpd_queue_power_off_work(pd);
2684
2685 /* Unregister the device if it was created by genpd. */
2686 if (dev->bus == &genpd_bus_type)
2687 device_unregister(dev);
2688}
2689
2690static void genpd_dev_pm_sync(struct device *dev)
2691{
2692 struct generic_pm_domain *pd;
2693
2694 pd = dev_to_genpd(dev);
2695 if (IS_ERR(pd))
2696 return;
2697
2698 genpd_queue_power_off_work(pd);
2699}
2700
2701static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
2702 unsigned int index, bool power_on)
2703{
2704 struct of_phandle_args pd_args;
2705 struct generic_pm_domain *pd;
2706 int pstate;
2707 int ret;
2708
2709 ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
2710 "#power-domain-cells", index, &pd_args);
2711 if (ret < 0)
2712 return ret;
2713
2714 mutex_lock(&gpd_list_lock);
2715 pd = genpd_get_from_provider(&pd_args);
2716 of_node_put(pd_args.np);
2717 if (IS_ERR(pd)) {
2718 mutex_unlock(&gpd_list_lock);
2719 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
2720 __func__, PTR_ERR(pd));
2721 return driver_deferred_probe_check_state(base_dev);
2722 }
2723
2724 dev_dbg(dev, "adding to PM domain %s\n", pd->name);
2725
2726 ret = genpd_add_device(pd, dev, base_dev);
2727 mutex_unlock(&gpd_list_lock);
2728
2729 if (ret < 0)
2730 return dev_err_probe(dev, ret, "failed to add to PM domain %s\n", pd->name);
2731
2732 dev->pm_domain->detach = genpd_dev_pm_detach;
2733 dev->pm_domain->sync = genpd_dev_pm_sync;
2734
2735 /* Set the default performance state */
2736 pstate = of_get_required_opp_performance_state(dev->of_node, index);
2737 if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
2738 ret = pstate;
2739 goto err;
2740 } else if (pstate > 0) {
2741 ret = dev_pm_genpd_set_performance_state(dev, pstate);
2742 if (ret)
2743 goto err;
2744 dev_gpd_data(dev)->default_pstate = pstate;
2745 }
2746
2747 if (power_on) {
2748 genpd_lock(pd);
2749 ret = genpd_power_on(pd, 0);
2750 genpd_unlock(pd);
2751 }
2752
2753 if (ret) {
2754 /* Drop the default performance state */
2755 if (dev_gpd_data(dev)->default_pstate) {
2756 dev_pm_genpd_set_performance_state(dev, 0);
2757 dev_gpd_data(dev)->default_pstate = 0;
2758 }
2759
2760 genpd_remove_device(pd, dev);
2761 return -EPROBE_DEFER;
2762 }
2763
2764 return 1;
2765
2766err:
2767 dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
2768 pd->name, ret);
2769 genpd_remove_device(pd, dev);
2770 return ret;
2771}
2772
2773/**
2774 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
2775 * @dev: Device to attach.
2776 *
2777 * Parse device's OF node to find a PM domain specifier. If such is found,
2778 * attaches the device to retrieved pm_domain ops.
2779 *
2780 * Returns 1 on successfully attached PM domain, 0 when the device don't need a
2781 * PM domain or when multiple power-domains exists for it, else a negative error
2782 * code. Note that if a power-domain exists for the device, but it cannot be
2783 * found or turned on, then return -EPROBE_DEFER to ensure that the device is
2784 * not probed and to re-try again later.
2785 */
2786int genpd_dev_pm_attach(struct device *dev)
2787{
2788 if (!dev->of_node)
2789 return 0;
2790
2791 /*
2792 * Devices with multiple PM domains must be attached separately, as we
2793 * can only attach one PM domain per device.
2794 */
2795 if (of_count_phandle_with_args(dev->of_node, "power-domains",
2796 "#power-domain-cells") != 1)
2797 return 0;
2798
2799 return __genpd_dev_pm_attach(dev, dev, 0, true);
2800}
2801EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
2802
2803/**
2804 * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
2805 * @dev: The device used to lookup the PM domain.
2806 * @index: The index of the PM domain.
2807 *
2808 * Parse device's OF node to find a PM domain specifier at the provided @index.
2809 * If such is found, creates a virtual device and attaches it to the retrieved
2810 * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
2811 * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
2812 *
2813 * Returns the created virtual device if successfully attached PM domain, NULL
2814 * when the device don't need a PM domain, else an ERR_PTR() in case of
2815 * failures. If a power-domain exists for the device, but cannot be found or
2816 * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
2817 * is not probed and to re-try again later.
2818 */
2819struct device *genpd_dev_pm_attach_by_id(struct device *dev,
2820 unsigned int index)
2821{
2822 struct device *virt_dev;
2823 int num_domains;
2824 int ret;
2825
2826 if (!dev->of_node)
2827 return NULL;
2828
2829 /* Verify that the index is within a valid range. */
2830 num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
2831 "#power-domain-cells");
2832 if (index >= num_domains)
2833 return NULL;
2834
2835 /* Allocate and register device on the genpd bus. */
2836 virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
2837 if (!virt_dev)
2838 return ERR_PTR(-ENOMEM);
2839
2840 dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
2841 virt_dev->bus = &genpd_bus_type;
2842 virt_dev->release = genpd_release_dev;
2843 virt_dev->of_node = of_node_get(dev->of_node);
2844
2845 ret = device_register(virt_dev);
2846 if (ret) {
2847 put_device(virt_dev);
2848 return ERR_PTR(ret);
2849 }
2850
2851 /* Try to attach the device to the PM domain at the specified index. */
2852 ret = __genpd_dev_pm_attach(virt_dev, dev, index, false);
2853 if (ret < 1) {
2854 device_unregister(virt_dev);
2855 return ret ? ERR_PTR(ret) : NULL;
2856 }
2857
2858 pm_runtime_enable(virt_dev);
2859 genpd_queue_power_off_work(dev_to_genpd(virt_dev));
2860
2861 return virt_dev;
2862}
2863EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
2864
2865/**
2866 * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
2867 * @dev: The device used to lookup the PM domain.
2868 * @name: The name of the PM domain.
2869 *
2870 * Parse device's OF node to find a PM domain specifier using the
2871 * power-domain-names DT property. For further description see
2872 * genpd_dev_pm_attach_by_id().
2873 */
2874struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
2875{
2876 int index;
2877
2878 if (!dev->of_node)
2879 return NULL;
2880
2881 index = of_property_match_string(dev->of_node, "power-domain-names",
2882 name);
2883 if (index < 0)
2884 return NULL;
2885
2886 return genpd_dev_pm_attach_by_id(dev, index);
2887}
2888
2889static const struct of_device_id idle_state_match[] = {
2890 { .compatible = "domain-idle-state", },
2891 { }
2892};
2893
2894static int genpd_parse_state(struct genpd_power_state *genpd_state,
2895 struct device_node *state_node)
2896{
2897 int err;
2898 u32 residency;
2899 u32 entry_latency, exit_latency;
2900
2901 err = of_property_read_u32(state_node, "entry-latency-us",
2902 &entry_latency);
2903 if (err) {
2904 pr_debug(" * %pOF missing entry-latency-us property\n",
2905 state_node);
2906 return -EINVAL;
2907 }
2908
2909 err = of_property_read_u32(state_node, "exit-latency-us",
2910 &exit_latency);
2911 if (err) {
2912 pr_debug(" * %pOF missing exit-latency-us property\n",
2913 state_node);
2914 return -EINVAL;
2915 }
2916
2917 err = of_property_read_u32(state_node, "min-residency-us", &residency);
2918 if (!err)
2919 genpd_state->residency_ns = 1000 * residency;
2920
2921 genpd_state->power_on_latency_ns = 1000 * exit_latency;
2922 genpd_state->power_off_latency_ns = 1000 * entry_latency;
2923 genpd_state->fwnode = &state_node->fwnode;
2924
2925 return 0;
2926}
2927
2928static int genpd_iterate_idle_states(struct device_node *dn,
2929 struct genpd_power_state *states)
2930{
2931 int ret;
2932 struct of_phandle_iterator it;
2933 struct device_node *np;
2934 int i = 0;
2935
2936 ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
2937 if (ret <= 0)
2938 return ret == -ENOENT ? 0 : ret;
2939
2940 /* Loop over the phandles until all the requested entry is found */
2941 of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
2942 np = it.node;
2943 if (!of_match_node(idle_state_match, np))
2944 continue;
2945
2946 if (!of_device_is_available(np))
2947 continue;
2948
2949 if (states) {
2950 ret = genpd_parse_state(&states[i], np);
2951 if (ret) {
2952 pr_err("Parsing idle state node %pOF failed with err %d\n",
2953 np, ret);
2954 of_node_put(np);
2955 return ret;
2956 }
2957 }
2958 i++;
2959 }
2960
2961 return i;
2962}
2963
2964/**
2965 * of_genpd_parse_idle_states: Return array of idle states for the genpd.
2966 *
2967 * @dn: The genpd device node
2968 * @states: The pointer to which the state array will be saved.
2969 * @n: The count of elements in the array returned from this function.
2970 *
2971 * Returns the device states parsed from the OF node. The memory for the states
2972 * is allocated by this function and is the responsibility of the caller to
2973 * free the memory after use. If any or zero compatible domain idle states is
2974 * found it returns 0 and in case of errors, a negative error code is returned.
2975 */
2976int of_genpd_parse_idle_states(struct device_node *dn,
2977 struct genpd_power_state **states, int *n)
2978{
2979 struct genpd_power_state *st;
2980 int ret;
2981
2982 ret = genpd_iterate_idle_states(dn, NULL);
2983 if (ret < 0)
2984 return ret;
2985
2986 if (!ret) {
2987 *states = NULL;
2988 *n = 0;
2989 return 0;
2990 }
2991
2992 st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
2993 if (!st)
2994 return -ENOMEM;
2995
2996 ret = genpd_iterate_idle_states(dn, st);
2997 if (ret <= 0) {
2998 kfree(st);
2999 return ret < 0 ? ret : -EINVAL;
3000 }
3001
3002 *states = st;
3003 *n = ret;
3004
3005 return 0;
3006}
3007EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
3008
3009/**
3010 * pm_genpd_opp_to_performance_state - Gets performance state of the genpd from its OPP node.
3011 *
3012 * @genpd_dev: Genpd's device for which the performance-state needs to be found.
3013 * @opp: struct dev_pm_opp of the OPP for which we need to find performance
3014 * state.
3015 *
3016 * Returns performance state encoded in the OPP of the genpd. This calls
3017 * platform specific genpd->opp_to_performance_state() callback to translate
3018 * power domain OPP to performance state.
3019 *
3020 * Returns performance state on success and 0 on failure.
3021 */
3022unsigned int pm_genpd_opp_to_performance_state(struct device *genpd_dev,
3023 struct dev_pm_opp *opp)
3024{
3025 struct generic_pm_domain *genpd = NULL;
3026 int state;
3027
3028 genpd = container_of(genpd_dev, struct generic_pm_domain, dev);
3029
3030 if (unlikely(!genpd->opp_to_performance_state))
3031 return 0;
3032
3033 genpd_lock(genpd);
3034 state = genpd->opp_to_performance_state(genpd, opp);
3035 genpd_unlock(genpd);
3036
3037 return state;
3038}
3039EXPORT_SYMBOL_GPL(pm_genpd_opp_to_performance_state);
3040
3041static int __init genpd_bus_init(void)
3042{
3043 return bus_register(&genpd_bus_type);
3044}
3045core_initcall(genpd_bus_init);
3046
3047#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
3048
3049
3050/*** debugfs support ***/
3051
3052#ifdef CONFIG_DEBUG_FS
3053/*
3054 * TODO: This function is a slightly modified version of rtpm_status_show
3055 * from sysfs.c, so generalize it.
3056 */
3057static void rtpm_status_str(struct seq_file *s, struct device *dev)
3058{
3059 static const char * const status_lookup[] = {
3060 [RPM_ACTIVE] = "active",
3061 [RPM_RESUMING] = "resuming",
3062 [RPM_SUSPENDED] = "suspended",
3063 [RPM_SUSPENDING] = "suspending"
3064 };
3065 const char *p = "";
3066
3067 if (dev->power.runtime_error)
3068 p = "error";
3069 else if (dev->power.disable_depth)
3070 p = "unsupported";
3071 else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
3072 p = status_lookup[dev->power.runtime_status];
3073 else
3074 WARN_ON(1);
3075
3076 seq_printf(s, "%-25s ", p);
3077}
3078
3079static void perf_status_str(struct seq_file *s, struct device *dev)
3080{
3081 struct generic_pm_domain_data *gpd_data;
3082
3083 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
3084 seq_put_decimal_ull(s, "", gpd_data->performance_state);
3085}
3086
3087static int genpd_summary_one(struct seq_file *s,
3088 struct generic_pm_domain *genpd)
3089{
3090 static const char * const status_lookup[] = {
3091 [GENPD_STATE_ON] = "on",
3092 [GENPD_STATE_OFF] = "off"
3093 };
3094 struct pm_domain_data *pm_data;
3095 const char *kobj_path;
3096 struct gpd_link *link;
3097 char state[16];
3098 int ret;
3099
3100 ret = genpd_lock_interruptible(genpd);
3101 if (ret)
3102 return -ERESTARTSYS;
3103
3104 if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
3105 goto exit;
3106 if (!genpd_status_on(genpd))
3107 snprintf(state, sizeof(state), "%s-%u",
3108 status_lookup[genpd->status], genpd->state_idx);
3109 else
3110 snprintf(state, sizeof(state), "%s",
3111 status_lookup[genpd->status]);
3112 seq_printf(s, "%-30s %-50s %u", genpd->name, state, genpd->performance_state);
3113
3114 /*
3115 * Modifications on the list require holding locks on both
3116 * parent and child, so we are safe.
3117 * Also genpd->name is immutable.
3118 */
3119 list_for_each_entry(link, &genpd->parent_links, parent_node) {
3120 if (list_is_first(&link->parent_node, &genpd->parent_links))
3121 seq_printf(s, "\n%48s", " ");
3122 seq_printf(s, "%s", link->child->name);
3123 if (!list_is_last(&link->parent_node, &genpd->parent_links))
3124 seq_puts(s, ", ");
3125 }
3126
3127 list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
3128 kobj_path = kobject_get_path(&pm_data->dev->kobj,
3129 genpd_is_irq_safe(genpd) ?
3130 GFP_ATOMIC : GFP_KERNEL);
3131 if (kobj_path == NULL)
3132 continue;
3133
3134 seq_printf(s, "\n %-50s ", kobj_path);
3135 rtpm_status_str(s, pm_data->dev);
3136 perf_status_str(s, pm_data->dev);
3137 kfree(kobj_path);
3138 }
3139
3140 seq_puts(s, "\n");
3141exit:
3142 genpd_unlock(genpd);
3143
3144 return 0;
3145}
3146
3147static int summary_show(struct seq_file *s, void *data)
3148{
3149 struct generic_pm_domain *genpd;
3150 int ret = 0;
3151
3152 seq_puts(s, "domain status children performance\n");
3153 seq_puts(s, " /device runtime status\n");
3154 seq_puts(s, "----------------------------------------------------------------------------------------------\n");
3155
3156 ret = mutex_lock_interruptible(&gpd_list_lock);
3157 if (ret)
3158 return -ERESTARTSYS;
3159
3160 list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
3161 ret = genpd_summary_one(s, genpd);
3162 if (ret)
3163 break;
3164 }
3165 mutex_unlock(&gpd_list_lock);
3166
3167 return ret;
3168}
3169
3170static int status_show(struct seq_file *s, void *data)
3171{
3172 static const char * const status_lookup[] = {
3173 [GENPD_STATE_ON] = "on",
3174 [GENPD_STATE_OFF] = "off"
3175 };
3176
3177 struct generic_pm_domain *genpd = s->private;
3178 int ret = 0;
3179
3180 ret = genpd_lock_interruptible(genpd);
3181 if (ret)
3182 return -ERESTARTSYS;
3183
3184 if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
3185 goto exit;
3186
3187 if (genpd->status == GENPD_STATE_OFF)
3188 seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
3189 genpd->state_idx);
3190 else
3191 seq_printf(s, "%s\n", status_lookup[genpd->status]);
3192exit:
3193 genpd_unlock(genpd);
3194 return ret;
3195}
3196
3197static int sub_domains_show(struct seq_file *s, void *data)
3198{
3199 struct generic_pm_domain *genpd = s->private;
3200 struct gpd_link *link;
3201 int ret = 0;
3202
3203 ret = genpd_lock_interruptible(genpd);
3204 if (ret)
3205 return -ERESTARTSYS;
3206
3207 list_for_each_entry(link, &genpd->parent_links, parent_node)
3208 seq_printf(s, "%s\n", link->child->name);
3209
3210 genpd_unlock(genpd);
3211 return ret;
3212}
3213
3214static int idle_states_show(struct seq_file *s, void *data)
3215{
3216 struct generic_pm_domain *genpd = s->private;
3217 u64 now, delta, idle_time = 0;
3218 unsigned int i;
3219 int ret = 0;
3220
3221 ret = genpd_lock_interruptible(genpd);
3222 if (ret)
3223 return -ERESTARTSYS;
3224
3225 seq_puts(s, "State Time Spent(ms) Usage Rejected\n");
3226
3227 for (i = 0; i < genpd->state_count; i++) {
3228 idle_time += genpd->states[i].idle_time;
3229
3230 if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3231 now = ktime_get_mono_fast_ns();
3232 if (now > genpd->accounting_time) {
3233 delta = now - genpd->accounting_time;
3234 idle_time += delta;
3235 }
3236 }
3237
3238 do_div(idle_time, NSEC_PER_MSEC);
3239 seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
3240 genpd->states[i].usage, genpd->states[i].rejected);
3241 }
3242
3243 genpd_unlock(genpd);
3244 return ret;
3245}
3246
3247static int active_time_show(struct seq_file *s, void *data)
3248{
3249 struct generic_pm_domain *genpd = s->private;
3250 u64 now, on_time, delta = 0;
3251 int ret = 0;
3252
3253 ret = genpd_lock_interruptible(genpd);
3254 if (ret)
3255 return -ERESTARTSYS;
3256
3257 if (genpd->status == GENPD_STATE_ON) {
3258 now = ktime_get_mono_fast_ns();
3259 if (now > genpd->accounting_time)
3260 delta = now - genpd->accounting_time;
3261 }
3262
3263 on_time = genpd->on_time + delta;
3264 do_div(on_time, NSEC_PER_MSEC);
3265 seq_printf(s, "%llu ms\n", on_time);
3266
3267 genpd_unlock(genpd);
3268 return ret;
3269}
3270
3271static int total_idle_time_show(struct seq_file *s, void *data)
3272{
3273 struct generic_pm_domain *genpd = s->private;
3274 u64 now, delta, total = 0;
3275 unsigned int i;
3276 int ret = 0;
3277
3278 ret = genpd_lock_interruptible(genpd);
3279 if (ret)
3280 return -ERESTARTSYS;
3281
3282 for (i = 0; i < genpd->state_count; i++) {
3283 total += genpd->states[i].idle_time;
3284
3285 if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
3286 now = ktime_get_mono_fast_ns();
3287 if (now > genpd->accounting_time) {
3288 delta = now - genpd->accounting_time;
3289 total += delta;
3290 }
3291 }
3292 }
3293
3294 do_div(total, NSEC_PER_MSEC);
3295 seq_printf(s, "%llu ms\n", total);
3296
3297 genpd_unlock(genpd);
3298 return ret;
3299}
3300
3301
3302static int devices_show(struct seq_file *s, void *data)
3303{
3304 struct generic_pm_domain *genpd = s->private;
3305 struct pm_domain_data *pm_data;
3306 const char *kobj_path;
3307 int ret = 0;
3308
3309 ret = genpd_lock_interruptible(genpd);
3310 if (ret)
3311 return -ERESTARTSYS;
3312
3313 list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
3314 kobj_path = kobject_get_path(&pm_data->dev->kobj,
3315 genpd_is_irq_safe(genpd) ?
3316 GFP_ATOMIC : GFP_KERNEL);
3317 if (kobj_path == NULL)
3318 continue;
3319
3320 seq_printf(s, "%s\n", kobj_path);
3321 kfree(kobj_path);
3322 }
3323
3324 genpd_unlock(genpd);
3325 return ret;
3326}
3327
3328static int perf_state_show(struct seq_file *s, void *data)
3329{
3330 struct generic_pm_domain *genpd = s->private;
3331
3332 if (genpd_lock_interruptible(genpd))
3333 return -ERESTARTSYS;
3334
3335 seq_printf(s, "%u\n", genpd->performance_state);
3336
3337 genpd_unlock(genpd);
3338 return 0;
3339}
3340
3341DEFINE_SHOW_ATTRIBUTE(summary);
3342DEFINE_SHOW_ATTRIBUTE(status);
3343DEFINE_SHOW_ATTRIBUTE(sub_domains);
3344DEFINE_SHOW_ATTRIBUTE(idle_states);
3345DEFINE_SHOW_ATTRIBUTE(active_time);
3346DEFINE_SHOW_ATTRIBUTE(total_idle_time);
3347DEFINE_SHOW_ATTRIBUTE(devices);
3348DEFINE_SHOW_ATTRIBUTE(perf_state);
3349
3350static void genpd_debug_add(struct generic_pm_domain *genpd)
3351{
3352 struct dentry *d;
3353
3354 if (!genpd_debugfs_dir)
3355 return;
3356
3357 d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
3358
3359 debugfs_create_file("current_state", 0444,
3360 d, genpd, &status_fops);
3361 debugfs_create_file("sub_domains", 0444,
3362 d, genpd, &sub_domains_fops);
3363 debugfs_create_file("idle_states", 0444,
3364 d, genpd, &idle_states_fops);
3365 debugfs_create_file("active_time", 0444,
3366 d, genpd, &active_time_fops);
3367 debugfs_create_file("total_idle_time", 0444,
3368 d, genpd, &total_idle_time_fops);
3369 debugfs_create_file("devices", 0444,
3370 d, genpd, &devices_fops);
3371 if (genpd->set_performance_state)
3372 debugfs_create_file("perf_state", 0444,
3373 d, genpd, &perf_state_fops);
3374}
3375
3376static int __init genpd_debug_init(void)
3377{
3378 struct generic_pm_domain *genpd;
3379
3380 genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
3381
3382 debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
3383 NULL, &summary_fops);
3384
3385 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
3386 genpd_debug_add(genpd);
3387
3388 return 0;
3389}
3390late_initcall(genpd_debug_init);
3391
3392static void __exit genpd_debug_exit(void)
3393{
3394 debugfs_remove_recursive(genpd_debugfs_dir);
3395}
3396__exitcall(genpd_debug_exit);
3397#endif /* CONFIG_DEBUG_FS */
1/*
2 * drivers/base/power/domain.c - Common code related to device power domains.
3 *
4 * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
5 *
6 * This file is released under the GPLv2.
7 */
8
9#include <linux/kernel.h>
10#include <linux/io.h>
11#include <linux/pm_runtime.h>
12#include <linux/pm_domain.h>
13#include <linux/pm_qos.h>
14#include <linux/slab.h>
15#include <linux/err.h>
16#include <linux/sched.h>
17#include <linux/suspend.h>
18#include <linux/export.h>
19
20#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
21({ \
22 type (*__routine)(struct device *__d); \
23 type __ret = (type)0; \
24 \
25 __routine = genpd->dev_ops.callback; \
26 if (__routine) { \
27 __ret = __routine(dev); \
28 } else { \
29 __routine = dev_gpd_data(dev)->ops.callback; \
30 if (__routine) \
31 __ret = __routine(dev); \
32 } \
33 __ret; \
34})
35
36#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \
37({ \
38 ktime_t __start = ktime_get(); \
39 type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \
40 s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \
41 struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \
42 if (!__retval && __elapsed > __td->field) { \
43 __td->field = __elapsed; \
44 dev_dbg(dev, name " latency exceeded, new value %lld ns\n", \
45 __elapsed); \
46 genpd->max_off_time_changed = true; \
47 __td->constraint_changed = true; \
48 } \
49 __retval; \
50})
51
52static LIST_HEAD(gpd_list);
53static DEFINE_MUTEX(gpd_list_lock);
54
55static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
56{
57 struct generic_pm_domain *genpd = NULL, *gpd;
58
59 if (IS_ERR_OR_NULL(domain_name))
60 return NULL;
61
62 mutex_lock(&gpd_list_lock);
63 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
64 if (!strcmp(gpd->name, domain_name)) {
65 genpd = gpd;
66 break;
67 }
68 }
69 mutex_unlock(&gpd_list_lock);
70 return genpd;
71}
72
73#ifdef CONFIG_PM
74
75struct generic_pm_domain *dev_to_genpd(struct device *dev)
76{
77 if (IS_ERR_OR_NULL(dev->pm_domain))
78 return ERR_PTR(-EINVAL);
79
80 return pd_to_genpd(dev->pm_domain);
81}
82
83static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
84{
85 return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
86 stop_latency_ns, "stop");
87}
88
89static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
90{
91 return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
92 start_latency_ns, "start");
93}
94
95static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
96{
97 bool ret = false;
98
99 if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
100 ret = !!atomic_dec_and_test(&genpd->sd_count);
101
102 return ret;
103}
104
105static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
106{
107 atomic_inc(&genpd->sd_count);
108 smp_mb__after_atomic_inc();
109}
110
111static void genpd_acquire_lock(struct generic_pm_domain *genpd)
112{
113 DEFINE_WAIT(wait);
114
115 mutex_lock(&genpd->lock);
116 /*
117 * Wait for the domain to transition into either the active,
118 * or the power off state.
119 */
120 for (;;) {
121 prepare_to_wait(&genpd->status_wait_queue, &wait,
122 TASK_UNINTERRUPTIBLE);
123 if (genpd->status == GPD_STATE_ACTIVE
124 || genpd->status == GPD_STATE_POWER_OFF)
125 break;
126 mutex_unlock(&genpd->lock);
127
128 schedule();
129
130 mutex_lock(&genpd->lock);
131 }
132 finish_wait(&genpd->status_wait_queue, &wait);
133}
134
135static void genpd_release_lock(struct generic_pm_domain *genpd)
136{
137 mutex_unlock(&genpd->lock);
138}
139
140static void genpd_set_active(struct generic_pm_domain *genpd)
141{
142 if (genpd->resume_count == 0)
143 genpd->status = GPD_STATE_ACTIVE;
144}
145
146static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
147{
148 s64 usecs64;
149
150 if (!genpd->cpu_data)
151 return;
152
153 usecs64 = genpd->power_on_latency_ns;
154 do_div(usecs64, NSEC_PER_USEC);
155 usecs64 += genpd->cpu_data->saved_exit_latency;
156 genpd->cpu_data->idle_state->exit_latency = usecs64;
157}
158
159/**
160 * __pm_genpd_poweron - Restore power to a given PM domain and its masters.
161 * @genpd: PM domain to power up.
162 *
163 * Restore power to @genpd and all of its masters so that it is possible to
164 * resume a device belonging to it.
165 */
166static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
167 __releases(&genpd->lock) __acquires(&genpd->lock)
168{
169 struct gpd_link *link;
170 DEFINE_WAIT(wait);
171 int ret = 0;
172
173 /* If the domain's master is being waited for, we have to wait too. */
174 for (;;) {
175 prepare_to_wait(&genpd->status_wait_queue, &wait,
176 TASK_UNINTERRUPTIBLE);
177 if (genpd->status != GPD_STATE_WAIT_MASTER)
178 break;
179 mutex_unlock(&genpd->lock);
180
181 schedule();
182
183 mutex_lock(&genpd->lock);
184 }
185 finish_wait(&genpd->status_wait_queue, &wait);
186
187 if (genpd->status == GPD_STATE_ACTIVE
188 || (genpd->prepared_count > 0 && genpd->suspend_power_off))
189 return 0;
190
191 if (genpd->status != GPD_STATE_POWER_OFF) {
192 genpd_set_active(genpd);
193 return 0;
194 }
195
196 if (genpd->cpu_data) {
197 cpuidle_pause_and_lock();
198 genpd->cpu_data->idle_state->disabled = true;
199 cpuidle_resume_and_unlock();
200 goto out;
201 }
202
203 /*
204 * The list is guaranteed not to change while the loop below is being
205 * executed, unless one of the masters' .power_on() callbacks fiddles
206 * with it.
207 */
208 list_for_each_entry(link, &genpd->slave_links, slave_node) {
209 genpd_sd_counter_inc(link->master);
210 genpd->status = GPD_STATE_WAIT_MASTER;
211
212 mutex_unlock(&genpd->lock);
213
214 ret = pm_genpd_poweron(link->master);
215
216 mutex_lock(&genpd->lock);
217
218 /*
219 * The "wait for parent" status is guaranteed not to change
220 * while the master is powering on.
221 */
222 genpd->status = GPD_STATE_POWER_OFF;
223 wake_up_all(&genpd->status_wait_queue);
224 if (ret) {
225 genpd_sd_counter_dec(link->master);
226 goto err;
227 }
228 }
229
230 if (genpd->power_on) {
231 ktime_t time_start = ktime_get();
232 s64 elapsed_ns;
233
234 ret = genpd->power_on(genpd);
235 if (ret)
236 goto err;
237
238 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
239 if (elapsed_ns > genpd->power_on_latency_ns) {
240 genpd->power_on_latency_ns = elapsed_ns;
241 genpd->max_off_time_changed = true;
242 genpd_recalc_cpu_exit_latency(genpd);
243 if (genpd->name)
244 pr_warning("%s: Power-on latency exceeded, "
245 "new value %lld ns\n", genpd->name,
246 elapsed_ns);
247 }
248 }
249
250 out:
251 genpd_set_active(genpd);
252
253 return 0;
254
255 err:
256 list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
257 genpd_sd_counter_dec(link->master);
258
259 return ret;
260}
261
262/**
263 * pm_genpd_poweron - Restore power to a given PM domain and its masters.
264 * @genpd: PM domain to power up.
265 */
266int pm_genpd_poweron(struct generic_pm_domain *genpd)
267{
268 int ret;
269
270 mutex_lock(&genpd->lock);
271 ret = __pm_genpd_poweron(genpd);
272 mutex_unlock(&genpd->lock);
273 return ret;
274}
275
276/**
277 * pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
278 * @domain_name: Name of the PM domain to power up.
279 */
280int pm_genpd_name_poweron(const char *domain_name)
281{
282 struct generic_pm_domain *genpd;
283
284 genpd = pm_genpd_lookup_name(domain_name);
285 return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
286}
287
288#endif /* CONFIG_PM */
289
290#ifdef CONFIG_PM_RUNTIME
291
292static int genpd_start_dev_no_timing(struct generic_pm_domain *genpd,
293 struct device *dev)
294{
295 return GENPD_DEV_CALLBACK(genpd, int, start, dev);
296}
297
298static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
299{
300 return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
301 save_state_latency_ns, "state save");
302}
303
304static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev)
305{
306 return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
307 restore_state_latency_ns,
308 "state restore");
309}
310
311static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
312 unsigned long val, void *ptr)
313{
314 struct generic_pm_domain_data *gpd_data;
315 struct device *dev;
316
317 gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
318
319 mutex_lock(&gpd_data->lock);
320 dev = gpd_data->base.dev;
321 if (!dev) {
322 mutex_unlock(&gpd_data->lock);
323 return NOTIFY_DONE;
324 }
325 mutex_unlock(&gpd_data->lock);
326
327 for (;;) {
328 struct generic_pm_domain *genpd;
329 struct pm_domain_data *pdd;
330
331 spin_lock_irq(&dev->power.lock);
332
333 pdd = dev->power.subsys_data ?
334 dev->power.subsys_data->domain_data : NULL;
335 if (pdd && pdd->dev) {
336 to_gpd_data(pdd)->td.constraint_changed = true;
337 genpd = dev_to_genpd(dev);
338 } else {
339 genpd = ERR_PTR(-ENODATA);
340 }
341
342 spin_unlock_irq(&dev->power.lock);
343
344 if (!IS_ERR(genpd)) {
345 mutex_lock(&genpd->lock);
346 genpd->max_off_time_changed = true;
347 mutex_unlock(&genpd->lock);
348 }
349
350 dev = dev->parent;
351 if (!dev || dev->power.ignore_children)
352 break;
353 }
354
355 return NOTIFY_DONE;
356}
357
358/**
359 * __pm_genpd_save_device - Save the pre-suspend state of a device.
360 * @pdd: Domain data of the device to save the state of.
361 * @genpd: PM domain the device belongs to.
362 */
363static int __pm_genpd_save_device(struct pm_domain_data *pdd,
364 struct generic_pm_domain *genpd)
365 __releases(&genpd->lock) __acquires(&genpd->lock)
366{
367 struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
368 struct device *dev = pdd->dev;
369 int ret = 0;
370
371 if (gpd_data->need_restore)
372 return 0;
373
374 mutex_unlock(&genpd->lock);
375
376 genpd_start_dev(genpd, dev);
377 ret = genpd_save_dev(genpd, dev);
378 genpd_stop_dev(genpd, dev);
379
380 mutex_lock(&genpd->lock);
381
382 if (!ret)
383 gpd_data->need_restore = true;
384
385 return ret;
386}
387
388/**
389 * __pm_genpd_restore_device - Restore the pre-suspend state of a device.
390 * @pdd: Domain data of the device to restore the state of.
391 * @genpd: PM domain the device belongs to.
392 */
393static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
394 struct generic_pm_domain *genpd)
395 __releases(&genpd->lock) __acquires(&genpd->lock)
396{
397 struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
398 struct device *dev = pdd->dev;
399 bool need_restore = gpd_data->need_restore;
400
401 gpd_data->need_restore = false;
402 mutex_unlock(&genpd->lock);
403
404 genpd_start_dev(genpd, dev);
405 if (need_restore)
406 genpd_restore_dev(genpd, dev);
407
408 mutex_lock(&genpd->lock);
409}
410
411/**
412 * genpd_abort_poweroff - Check if a PM domain power off should be aborted.
413 * @genpd: PM domain to check.
414 *
415 * Return true if a PM domain's status changed to GPD_STATE_ACTIVE during
416 * a "power off" operation, which means that a "power on" has occured in the
417 * meantime, or if its resume_count field is different from zero, which means
418 * that one of its devices has been resumed in the meantime.
419 */
420static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
421{
422 return genpd->status == GPD_STATE_WAIT_MASTER
423 || genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
424}
425
426/**
427 * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
428 * @genpd: PM domait to power off.
429 *
430 * Queue up the execution of pm_genpd_poweroff() unless it's already been done
431 * before.
432 */
433void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
434{
435 queue_work(pm_wq, &genpd->power_off_work);
436}
437
438/**
439 * pm_genpd_poweroff - Remove power from a given PM domain.
440 * @genpd: PM domain to power down.
441 *
442 * If all of the @genpd's devices have been suspended and all of its subdomains
443 * have been powered down, run the runtime suspend callbacks provided by all of
444 * the @genpd's devices' drivers and remove power from @genpd.
445 */
446static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
447 __releases(&genpd->lock) __acquires(&genpd->lock)
448{
449 struct pm_domain_data *pdd;
450 struct gpd_link *link;
451 unsigned int not_suspended;
452 int ret = 0;
453
454 start:
455 /*
456 * Do not try to power off the domain in the following situations:
457 * (1) The domain is already in the "power off" state.
458 * (2) The domain is waiting for its master to power up.
459 * (3) One of the domain's devices is being resumed right now.
460 * (4) System suspend is in progress.
461 */
462 if (genpd->status == GPD_STATE_POWER_OFF
463 || genpd->status == GPD_STATE_WAIT_MASTER
464 || genpd->resume_count > 0 || genpd->prepared_count > 0)
465 return 0;
466
467 if (atomic_read(&genpd->sd_count) > 0)
468 return -EBUSY;
469
470 not_suspended = 0;
471 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
472 enum pm_qos_flags_status stat;
473
474 stat = dev_pm_qos_flags(pdd->dev,
475 PM_QOS_FLAG_NO_POWER_OFF
476 | PM_QOS_FLAG_REMOTE_WAKEUP);
477 if (stat > PM_QOS_FLAGS_NONE)
478 return -EBUSY;
479
480 if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
481 || pdd->dev->power.irq_safe))
482 not_suspended++;
483 }
484
485 if (not_suspended > genpd->in_progress)
486 return -EBUSY;
487
488 if (genpd->poweroff_task) {
489 /*
490 * Another instance of pm_genpd_poweroff() is executing
491 * callbacks, so tell it to start over and return.
492 */
493 genpd->status = GPD_STATE_REPEAT;
494 return 0;
495 }
496
497 if (genpd->gov && genpd->gov->power_down_ok) {
498 if (!genpd->gov->power_down_ok(&genpd->domain))
499 return -EAGAIN;
500 }
501
502 genpd->status = GPD_STATE_BUSY;
503 genpd->poweroff_task = current;
504
505 list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
506 ret = atomic_read(&genpd->sd_count) == 0 ?
507 __pm_genpd_save_device(pdd, genpd) : -EBUSY;
508
509 if (genpd_abort_poweroff(genpd))
510 goto out;
511
512 if (ret) {
513 genpd_set_active(genpd);
514 goto out;
515 }
516
517 if (genpd->status == GPD_STATE_REPEAT) {
518 genpd->poweroff_task = NULL;
519 goto start;
520 }
521 }
522
523 if (genpd->cpu_data) {
524 /*
525 * If cpu_data is set, cpuidle should turn the domain off when
526 * the CPU in it is idle. In that case we don't decrement the
527 * subdomain counts of the master domains, so that power is not
528 * removed from the current domain prematurely as a result of
529 * cutting off the masters' power.
530 */
531 genpd->status = GPD_STATE_POWER_OFF;
532 cpuidle_pause_and_lock();
533 genpd->cpu_data->idle_state->disabled = false;
534 cpuidle_resume_and_unlock();
535 goto out;
536 }
537
538 if (genpd->power_off) {
539 ktime_t time_start;
540 s64 elapsed_ns;
541
542 if (atomic_read(&genpd->sd_count) > 0) {
543 ret = -EBUSY;
544 goto out;
545 }
546
547 time_start = ktime_get();
548
549 /*
550 * If sd_count > 0 at this point, one of the subdomains hasn't
551 * managed to call pm_genpd_poweron() for the master yet after
552 * incrementing it. In that case pm_genpd_poweron() will wait
553 * for us to drop the lock, so we can call .power_off() and let
554 * the pm_genpd_poweron() restore power for us (this shouldn't
555 * happen very often).
556 */
557 ret = genpd->power_off(genpd);
558 if (ret == -EBUSY) {
559 genpd_set_active(genpd);
560 goto out;
561 }
562
563 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
564 if (elapsed_ns > genpd->power_off_latency_ns) {
565 genpd->power_off_latency_ns = elapsed_ns;
566 genpd->max_off_time_changed = true;
567 if (genpd->name)
568 pr_warning("%s: Power-off latency exceeded, "
569 "new value %lld ns\n", genpd->name,
570 elapsed_ns);
571 }
572 }
573
574 genpd->status = GPD_STATE_POWER_OFF;
575
576 list_for_each_entry(link, &genpd->slave_links, slave_node) {
577 genpd_sd_counter_dec(link->master);
578 genpd_queue_power_off_work(link->master);
579 }
580
581 out:
582 genpd->poweroff_task = NULL;
583 wake_up_all(&genpd->status_wait_queue);
584 return ret;
585}
586
587/**
588 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
589 * @work: Work structure used for scheduling the execution of this function.
590 */
591static void genpd_power_off_work_fn(struct work_struct *work)
592{
593 struct generic_pm_domain *genpd;
594
595 genpd = container_of(work, struct generic_pm_domain, power_off_work);
596
597 genpd_acquire_lock(genpd);
598 pm_genpd_poweroff(genpd);
599 genpd_release_lock(genpd);
600}
601
602/**
603 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
604 * @dev: Device to suspend.
605 *
606 * Carry out a runtime suspend of a device under the assumption that its
607 * pm_domain field points to the domain member of an object of type
608 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
609 */
610static int pm_genpd_runtime_suspend(struct device *dev)
611{
612 struct generic_pm_domain *genpd;
613 bool (*stop_ok)(struct device *__dev);
614 int ret;
615
616 dev_dbg(dev, "%s()\n", __func__);
617
618 genpd = dev_to_genpd(dev);
619 if (IS_ERR(genpd))
620 return -EINVAL;
621
622 might_sleep_if(!genpd->dev_irq_safe);
623
624 stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
625 if (stop_ok && !stop_ok(dev))
626 return -EBUSY;
627
628 ret = genpd_stop_dev(genpd, dev);
629 if (ret)
630 return ret;
631
632 /*
633 * If power.irq_safe is set, this routine will be run with interrupts
634 * off, so it can't use mutexes.
635 */
636 if (dev->power.irq_safe)
637 return 0;
638
639 mutex_lock(&genpd->lock);
640 genpd->in_progress++;
641 pm_genpd_poweroff(genpd);
642 genpd->in_progress--;
643 mutex_unlock(&genpd->lock);
644
645 return 0;
646}
647
648/**
649 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
650 * @dev: Device to resume.
651 *
652 * Carry out a runtime resume of a device under the assumption that its
653 * pm_domain field points to the domain member of an object of type
654 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
655 */
656static int pm_genpd_runtime_resume(struct device *dev)
657{
658 struct generic_pm_domain *genpd;
659 DEFINE_WAIT(wait);
660 int ret;
661
662 dev_dbg(dev, "%s()\n", __func__);
663
664 genpd = dev_to_genpd(dev);
665 if (IS_ERR(genpd))
666 return -EINVAL;
667
668 might_sleep_if(!genpd->dev_irq_safe);
669
670 /* If power.irq_safe, the PM domain is never powered off. */
671 if (dev->power.irq_safe)
672 return genpd_start_dev_no_timing(genpd, dev);
673
674 mutex_lock(&genpd->lock);
675 ret = __pm_genpd_poweron(genpd);
676 if (ret) {
677 mutex_unlock(&genpd->lock);
678 return ret;
679 }
680 genpd->status = GPD_STATE_BUSY;
681 genpd->resume_count++;
682 for (;;) {
683 prepare_to_wait(&genpd->status_wait_queue, &wait,
684 TASK_UNINTERRUPTIBLE);
685 /*
686 * If current is the powering off task, we have been called
687 * reentrantly from one of the device callbacks, so we should
688 * not wait.
689 */
690 if (!genpd->poweroff_task || genpd->poweroff_task == current)
691 break;
692 mutex_unlock(&genpd->lock);
693
694 schedule();
695
696 mutex_lock(&genpd->lock);
697 }
698 finish_wait(&genpd->status_wait_queue, &wait);
699 __pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
700 genpd->resume_count--;
701 genpd_set_active(genpd);
702 wake_up_all(&genpd->status_wait_queue);
703 mutex_unlock(&genpd->lock);
704
705 return 0;
706}
707
708static bool pd_ignore_unused;
709static int __init pd_ignore_unused_setup(char *__unused)
710{
711 pd_ignore_unused = true;
712 return 1;
713}
714__setup("pd_ignore_unused", pd_ignore_unused_setup);
715
716/**
717 * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
718 */
719void pm_genpd_poweroff_unused(void)
720{
721 struct generic_pm_domain *genpd;
722
723 if (pd_ignore_unused) {
724 pr_warn("genpd: Not disabling unused power domains\n");
725 return;
726 }
727
728 mutex_lock(&gpd_list_lock);
729
730 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
731 genpd_queue_power_off_work(genpd);
732
733 mutex_unlock(&gpd_list_lock);
734}
735
736#else
737
738static inline int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
739 unsigned long val, void *ptr)
740{
741 return NOTIFY_DONE;
742}
743
744static inline void genpd_power_off_work_fn(struct work_struct *work) {}
745
746#define pm_genpd_runtime_suspend NULL
747#define pm_genpd_runtime_resume NULL
748
749#endif /* CONFIG_PM_RUNTIME */
750
751#ifdef CONFIG_PM_SLEEP
752
753/**
754 * pm_genpd_present - Check if the given PM domain has been initialized.
755 * @genpd: PM domain to check.
756 */
757static bool pm_genpd_present(struct generic_pm_domain *genpd)
758{
759 struct generic_pm_domain *gpd;
760
761 if (IS_ERR_OR_NULL(genpd))
762 return false;
763
764 list_for_each_entry(gpd, &gpd_list, gpd_list_node)
765 if (gpd == genpd)
766 return true;
767
768 return false;
769}
770
771static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
772 struct device *dev)
773{
774 return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
775}
776
777static int genpd_suspend_dev(struct generic_pm_domain *genpd, struct device *dev)
778{
779 return GENPD_DEV_CALLBACK(genpd, int, suspend, dev);
780}
781
782static int genpd_suspend_late(struct generic_pm_domain *genpd, struct device *dev)
783{
784 return GENPD_DEV_CALLBACK(genpd, int, suspend_late, dev);
785}
786
787static int genpd_resume_early(struct generic_pm_domain *genpd, struct device *dev)
788{
789 return GENPD_DEV_CALLBACK(genpd, int, resume_early, dev);
790}
791
792static int genpd_resume_dev(struct generic_pm_domain *genpd, struct device *dev)
793{
794 return GENPD_DEV_CALLBACK(genpd, int, resume, dev);
795}
796
797static int genpd_freeze_dev(struct generic_pm_domain *genpd, struct device *dev)
798{
799 return GENPD_DEV_CALLBACK(genpd, int, freeze, dev);
800}
801
802static int genpd_freeze_late(struct generic_pm_domain *genpd, struct device *dev)
803{
804 return GENPD_DEV_CALLBACK(genpd, int, freeze_late, dev);
805}
806
807static int genpd_thaw_early(struct generic_pm_domain *genpd, struct device *dev)
808{
809 return GENPD_DEV_CALLBACK(genpd, int, thaw_early, dev);
810}
811
812static int genpd_thaw_dev(struct generic_pm_domain *genpd, struct device *dev)
813{
814 return GENPD_DEV_CALLBACK(genpd, int, thaw, dev);
815}
816
817/**
818 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
819 * @genpd: PM domain to power off, if possible.
820 *
821 * Check if the given PM domain can be powered off (during system suspend or
822 * hibernation) and do that if so. Also, in that case propagate to its masters.
823 *
824 * This function is only called in "noirq" and "syscore" stages of system power
825 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
826 * executed sequentially, so it is guaranteed that it will never run twice in
827 * parallel).
828 */
829static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
830{
831 struct gpd_link *link;
832
833 if (genpd->status == GPD_STATE_POWER_OFF)
834 return;
835
836 if (genpd->suspended_count != genpd->device_count
837 || atomic_read(&genpd->sd_count) > 0)
838 return;
839
840 if (genpd->power_off)
841 genpd->power_off(genpd);
842
843 genpd->status = GPD_STATE_POWER_OFF;
844
845 list_for_each_entry(link, &genpd->slave_links, slave_node) {
846 genpd_sd_counter_dec(link->master);
847 pm_genpd_sync_poweroff(link->master);
848 }
849}
850
851/**
852 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
853 * @genpd: PM domain to power on.
854 *
855 * This function is only called in "noirq" and "syscore" stages of system power
856 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
857 * executed sequentially, so it is guaranteed that it will never run twice in
858 * parallel).
859 */
860static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd)
861{
862 struct gpd_link *link;
863
864 if (genpd->status != GPD_STATE_POWER_OFF)
865 return;
866
867 list_for_each_entry(link, &genpd->slave_links, slave_node) {
868 pm_genpd_sync_poweron(link->master);
869 genpd_sd_counter_inc(link->master);
870 }
871
872 if (genpd->power_on)
873 genpd->power_on(genpd);
874
875 genpd->status = GPD_STATE_ACTIVE;
876}
877
878/**
879 * resume_needed - Check whether to resume a device before system suspend.
880 * @dev: Device to check.
881 * @genpd: PM domain the device belongs to.
882 *
883 * There are two cases in which a device that can wake up the system from sleep
884 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
885 * to wake up the system and it has to remain active for this purpose while the
886 * system is in the sleep state and (2) if the device is not enabled to wake up
887 * the system from sleep states and it generally doesn't generate wakeup signals
888 * by itself (those signals are generated on its behalf by other parts of the
889 * system). In the latter case it may be necessary to reconfigure the device's
890 * wakeup settings during system suspend, because it may have been set up to
891 * signal remote wakeup from the system's working state as needed by runtime PM.
892 * Return 'true' in either of the above cases.
893 */
894static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
895{
896 bool active_wakeup;
897
898 if (!device_can_wakeup(dev))
899 return false;
900
901 active_wakeup = genpd_dev_active_wakeup(genpd, dev);
902 return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
903}
904
905/**
906 * pm_genpd_prepare - Start power transition of a device in a PM domain.
907 * @dev: Device to start the transition of.
908 *
909 * Start a power transition of a device (during a system-wide power transition)
910 * under the assumption that its pm_domain field points to the domain member of
911 * an object of type struct generic_pm_domain representing a PM domain
912 * consisting of I/O devices.
913 */
914static int pm_genpd_prepare(struct device *dev)
915{
916 struct generic_pm_domain *genpd;
917 int ret;
918
919 dev_dbg(dev, "%s()\n", __func__);
920
921 genpd = dev_to_genpd(dev);
922 if (IS_ERR(genpd))
923 return -EINVAL;
924
925 /*
926 * If a wakeup request is pending for the device, it should be woken up
927 * at this point and a system wakeup event should be reported if it's
928 * set up to wake up the system from sleep states.
929 */
930 pm_runtime_get_noresume(dev);
931 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
932 pm_wakeup_event(dev, 0);
933
934 if (pm_wakeup_pending()) {
935 pm_runtime_put(dev);
936 return -EBUSY;
937 }
938
939 if (resume_needed(dev, genpd))
940 pm_runtime_resume(dev);
941
942 genpd_acquire_lock(genpd);
943
944 if (genpd->prepared_count++ == 0) {
945 genpd->suspended_count = 0;
946 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
947 }
948
949 genpd_release_lock(genpd);
950
951 if (genpd->suspend_power_off) {
952 pm_runtime_put_noidle(dev);
953 return 0;
954 }
955
956 /*
957 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
958 * so pm_genpd_poweron() will return immediately, but if the device
959 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
960 * to make it operational.
961 */
962 pm_runtime_resume(dev);
963 __pm_runtime_disable(dev, false);
964
965 ret = pm_generic_prepare(dev);
966 if (ret) {
967 mutex_lock(&genpd->lock);
968
969 if (--genpd->prepared_count == 0)
970 genpd->suspend_power_off = false;
971
972 mutex_unlock(&genpd->lock);
973 pm_runtime_enable(dev);
974 }
975
976 pm_runtime_put(dev);
977 return ret;
978}
979
980/**
981 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
982 * @dev: Device to suspend.
983 *
984 * Suspend a device under the assumption that its pm_domain field points to the
985 * domain member of an object of type struct generic_pm_domain representing
986 * a PM domain consisting of I/O devices.
987 */
988static int pm_genpd_suspend(struct device *dev)
989{
990 struct generic_pm_domain *genpd;
991
992 dev_dbg(dev, "%s()\n", __func__);
993
994 genpd = dev_to_genpd(dev);
995 if (IS_ERR(genpd))
996 return -EINVAL;
997
998 return genpd->suspend_power_off ? 0 : genpd_suspend_dev(genpd, dev);
999}
1000
1001/**
1002 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
1003 * @dev: Device to suspend.
1004 *
1005 * Carry out a late suspend of a device under the assumption that its
1006 * pm_domain field points to the domain member of an object of type
1007 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
1008 */
1009static int pm_genpd_suspend_late(struct device *dev)
1010{
1011 struct generic_pm_domain *genpd;
1012
1013 dev_dbg(dev, "%s()\n", __func__);
1014
1015 genpd = dev_to_genpd(dev);
1016 if (IS_ERR(genpd))
1017 return -EINVAL;
1018
1019 return genpd->suspend_power_off ? 0 : genpd_suspend_late(genpd, dev);
1020}
1021
1022/**
1023 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
1024 * @dev: Device to suspend.
1025 *
1026 * Stop the device and remove power from the domain if all devices in it have
1027 * been stopped.
1028 */
1029static int pm_genpd_suspend_noirq(struct device *dev)
1030{
1031 struct generic_pm_domain *genpd;
1032
1033 dev_dbg(dev, "%s()\n", __func__);
1034
1035 genpd = dev_to_genpd(dev);
1036 if (IS_ERR(genpd))
1037 return -EINVAL;
1038
1039 if (genpd->suspend_power_off
1040 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1041 return 0;
1042
1043 genpd_stop_dev(genpd, dev);
1044
1045 /*
1046 * Since all of the "noirq" callbacks are executed sequentially, it is
1047 * guaranteed that this function will never run twice in parallel for
1048 * the same PM domain, so it is not necessary to use locking here.
1049 */
1050 genpd->suspended_count++;
1051 pm_genpd_sync_poweroff(genpd);
1052
1053 return 0;
1054}
1055
1056/**
1057 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1058 * @dev: Device to resume.
1059 *
1060 * Restore power to the device's PM domain, if necessary, and start the device.
1061 */
1062static int pm_genpd_resume_noirq(struct device *dev)
1063{
1064 struct generic_pm_domain *genpd;
1065
1066 dev_dbg(dev, "%s()\n", __func__);
1067
1068 genpd = dev_to_genpd(dev);
1069 if (IS_ERR(genpd))
1070 return -EINVAL;
1071
1072 if (genpd->suspend_power_off
1073 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1074 return 0;
1075
1076 /*
1077 * Since all of the "noirq" callbacks are executed sequentially, it is
1078 * guaranteed that this function will never run twice in parallel for
1079 * the same PM domain, so it is not necessary to use locking here.
1080 */
1081 pm_genpd_sync_poweron(genpd);
1082 genpd->suspended_count--;
1083
1084 return genpd_start_dev(genpd, dev);
1085}
1086
1087/**
1088 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
1089 * @dev: Device to resume.
1090 *
1091 * Carry out an early resume of a device under the assumption that its
1092 * pm_domain field points to the domain member of an object of type
1093 * struct generic_pm_domain representing a power domain consisting of I/O
1094 * devices.
1095 */
1096static int pm_genpd_resume_early(struct device *dev)
1097{
1098 struct generic_pm_domain *genpd;
1099
1100 dev_dbg(dev, "%s()\n", __func__);
1101
1102 genpd = dev_to_genpd(dev);
1103 if (IS_ERR(genpd))
1104 return -EINVAL;
1105
1106 return genpd->suspend_power_off ? 0 : genpd_resume_early(genpd, dev);
1107}
1108
1109/**
1110 * pm_genpd_resume - Resume of device in an I/O PM domain.
1111 * @dev: Device to resume.
1112 *
1113 * Resume a device under the assumption that its pm_domain field points to the
1114 * domain member of an object of type struct generic_pm_domain representing
1115 * a power domain consisting of I/O devices.
1116 */
1117static int pm_genpd_resume(struct device *dev)
1118{
1119 struct generic_pm_domain *genpd;
1120
1121 dev_dbg(dev, "%s()\n", __func__);
1122
1123 genpd = dev_to_genpd(dev);
1124 if (IS_ERR(genpd))
1125 return -EINVAL;
1126
1127 return genpd->suspend_power_off ? 0 : genpd_resume_dev(genpd, dev);
1128}
1129
1130/**
1131 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
1132 * @dev: Device to freeze.
1133 *
1134 * Freeze a device under the assumption that its pm_domain field points to the
1135 * domain member of an object of type struct generic_pm_domain representing
1136 * a power domain consisting of I/O devices.
1137 */
1138static int pm_genpd_freeze(struct device *dev)
1139{
1140 struct generic_pm_domain *genpd;
1141
1142 dev_dbg(dev, "%s()\n", __func__);
1143
1144 genpd = dev_to_genpd(dev);
1145 if (IS_ERR(genpd))
1146 return -EINVAL;
1147
1148 return genpd->suspend_power_off ? 0 : genpd_freeze_dev(genpd, dev);
1149}
1150
1151/**
1152 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
1153 * @dev: Device to freeze.
1154 *
1155 * Carry out a late freeze of a device under the assumption that its
1156 * pm_domain field points to the domain member of an object of type
1157 * struct generic_pm_domain representing a power domain consisting of I/O
1158 * devices.
1159 */
1160static int pm_genpd_freeze_late(struct device *dev)
1161{
1162 struct generic_pm_domain *genpd;
1163
1164 dev_dbg(dev, "%s()\n", __func__);
1165
1166 genpd = dev_to_genpd(dev);
1167 if (IS_ERR(genpd))
1168 return -EINVAL;
1169
1170 return genpd->suspend_power_off ? 0 : genpd_freeze_late(genpd, dev);
1171}
1172
1173/**
1174 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1175 * @dev: Device to freeze.
1176 *
1177 * Carry out a late freeze of a device under the assumption that its
1178 * pm_domain field points to the domain member of an object of type
1179 * struct generic_pm_domain representing a power domain consisting of I/O
1180 * devices.
1181 */
1182static int pm_genpd_freeze_noirq(struct device *dev)
1183{
1184 struct generic_pm_domain *genpd;
1185
1186 dev_dbg(dev, "%s()\n", __func__);
1187
1188 genpd = dev_to_genpd(dev);
1189 if (IS_ERR(genpd))
1190 return -EINVAL;
1191
1192 return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
1193}
1194
1195/**
1196 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1197 * @dev: Device to thaw.
1198 *
1199 * Start the device, unless power has been removed from the domain already
1200 * before the system transition.
1201 */
1202static int pm_genpd_thaw_noirq(struct device *dev)
1203{
1204 struct generic_pm_domain *genpd;
1205
1206 dev_dbg(dev, "%s()\n", __func__);
1207
1208 genpd = dev_to_genpd(dev);
1209 if (IS_ERR(genpd))
1210 return -EINVAL;
1211
1212 return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
1213}
1214
1215/**
1216 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
1217 * @dev: Device to thaw.
1218 *
1219 * Carry out an early thaw of a device under the assumption that its
1220 * pm_domain field points to the domain member of an object of type
1221 * struct generic_pm_domain representing a power domain consisting of I/O
1222 * devices.
1223 */
1224static int pm_genpd_thaw_early(struct device *dev)
1225{
1226 struct generic_pm_domain *genpd;
1227
1228 dev_dbg(dev, "%s()\n", __func__);
1229
1230 genpd = dev_to_genpd(dev);
1231 if (IS_ERR(genpd))
1232 return -EINVAL;
1233
1234 return genpd->suspend_power_off ? 0 : genpd_thaw_early(genpd, dev);
1235}
1236
1237/**
1238 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1239 * @dev: Device to thaw.
1240 *
1241 * Thaw a device under the assumption that its pm_domain field points to the
1242 * domain member of an object of type struct generic_pm_domain representing
1243 * a power domain consisting of I/O devices.
1244 */
1245static int pm_genpd_thaw(struct device *dev)
1246{
1247 struct generic_pm_domain *genpd;
1248
1249 dev_dbg(dev, "%s()\n", __func__);
1250
1251 genpd = dev_to_genpd(dev);
1252 if (IS_ERR(genpd))
1253 return -EINVAL;
1254
1255 return genpd->suspend_power_off ? 0 : genpd_thaw_dev(genpd, dev);
1256}
1257
1258/**
1259 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1260 * @dev: Device to resume.
1261 *
1262 * Make sure the domain will be in the same power state as before the
1263 * hibernation the system is resuming from and start the device if necessary.
1264 */
1265static int pm_genpd_restore_noirq(struct device *dev)
1266{
1267 struct generic_pm_domain *genpd;
1268
1269 dev_dbg(dev, "%s()\n", __func__);
1270
1271 genpd = dev_to_genpd(dev);
1272 if (IS_ERR(genpd))
1273 return -EINVAL;
1274
1275 /*
1276 * Since all of the "noirq" callbacks are executed sequentially, it is
1277 * guaranteed that this function will never run twice in parallel for
1278 * the same PM domain, so it is not necessary to use locking here.
1279 *
1280 * At this point suspended_count == 0 means we are being run for the
1281 * first time for the given domain in the present cycle.
1282 */
1283 if (genpd->suspended_count++ == 0) {
1284 /*
1285 * The boot kernel might put the domain into arbitrary state,
1286 * so make it appear as powered off to pm_genpd_sync_poweron(),
1287 * so that it tries to power it on in case it was really off.
1288 */
1289 genpd->status = GPD_STATE_POWER_OFF;
1290 if (genpd->suspend_power_off) {
1291 /*
1292 * If the domain was off before the hibernation, make
1293 * sure it will be off going forward.
1294 */
1295 if (genpd->power_off)
1296 genpd->power_off(genpd);
1297
1298 return 0;
1299 }
1300 }
1301
1302 if (genpd->suspend_power_off)
1303 return 0;
1304
1305 pm_genpd_sync_poweron(genpd);
1306
1307 return genpd_start_dev(genpd, dev);
1308}
1309
1310/**
1311 * pm_genpd_complete - Complete power transition of a device in a power domain.
1312 * @dev: Device to complete the transition of.
1313 *
1314 * Complete a power transition of a device (during a system-wide power
1315 * transition) under the assumption that its pm_domain field points to the
1316 * domain member of an object of type struct generic_pm_domain representing
1317 * a power domain consisting of I/O devices.
1318 */
1319static void pm_genpd_complete(struct device *dev)
1320{
1321 struct generic_pm_domain *genpd;
1322 bool run_complete;
1323
1324 dev_dbg(dev, "%s()\n", __func__);
1325
1326 genpd = dev_to_genpd(dev);
1327 if (IS_ERR(genpd))
1328 return;
1329
1330 mutex_lock(&genpd->lock);
1331
1332 run_complete = !genpd->suspend_power_off;
1333 if (--genpd->prepared_count == 0)
1334 genpd->suspend_power_off = false;
1335
1336 mutex_unlock(&genpd->lock);
1337
1338 if (run_complete) {
1339 pm_generic_complete(dev);
1340 pm_runtime_set_active(dev);
1341 pm_runtime_enable(dev);
1342 pm_request_idle(dev);
1343 }
1344}
1345
1346/**
1347 * pm_genpd_syscore_switch - Switch power during system core suspend or resume.
1348 * @dev: Device that normally is marked as "always on" to switch power for.
1349 *
1350 * This routine may only be called during the system core (syscore) suspend or
1351 * resume phase for devices whose "always on" flags are set.
1352 */
1353void pm_genpd_syscore_switch(struct device *dev, bool suspend)
1354{
1355 struct generic_pm_domain *genpd;
1356
1357 genpd = dev_to_genpd(dev);
1358 if (!pm_genpd_present(genpd))
1359 return;
1360
1361 if (suspend) {
1362 genpd->suspended_count++;
1363 pm_genpd_sync_poweroff(genpd);
1364 } else {
1365 pm_genpd_sync_poweron(genpd);
1366 genpd->suspended_count--;
1367 }
1368}
1369EXPORT_SYMBOL_GPL(pm_genpd_syscore_switch);
1370
1371#else
1372
1373#define pm_genpd_prepare NULL
1374#define pm_genpd_suspend NULL
1375#define pm_genpd_suspend_late NULL
1376#define pm_genpd_suspend_noirq NULL
1377#define pm_genpd_resume_early NULL
1378#define pm_genpd_resume_noirq NULL
1379#define pm_genpd_resume NULL
1380#define pm_genpd_freeze NULL
1381#define pm_genpd_freeze_late NULL
1382#define pm_genpd_freeze_noirq NULL
1383#define pm_genpd_thaw_early NULL
1384#define pm_genpd_thaw_noirq NULL
1385#define pm_genpd_thaw NULL
1386#define pm_genpd_restore_noirq NULL
1387#define pm_genpd_complete NULL
1388
1389#endif /* CONFIG_PM_SLEEP */
1390
1391static struct generic_pm_domain_data *__pm_genpd_alloc_dev_data(struct device *dev)
1392{
1393 struct generic_pm_domain_data *gpd_data;
1394
1395 gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1396 if (!gpd_data)
1397 return NULL;
1398
1399 mutex_init(&gpd_data->lock);
1400 gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1401 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1402 return gpd_data;
1403}
1404
1405static void __pm_genpd_free_dev_data(struct device *dev,
1406 struct generic_pm_domain_data *gpd_data)
1407{
1408 dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1409 kfree(gpd_data);
1410}
1411
1412/**
1413 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1414 * @genpd: PM domain to add the device to.
1415 * @dev: Device to be added.
1416 * @td: Set of PM QoS timing parameters to attach to the device.
1417 */
1418int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1419 struct gpd_timing_data *td)
1420{
1421 struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1422 struct pm_domain_data *pdd;
1423 int ret = 0;
1424
1425 dev_dbg(dev, "%s()\n", __func__);
1426
1427 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1428 return -EINVAL;
1429
1430 gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1431 if (!gpd_data_new)
1432 return -ENOMEM;
1433
1434 genpd_acquire_lock(genpd);
1435
1436 if (genpd->prepared_count > 0) {
1437 ret = -EAGAIN;
1438 goto out;
1439 }
1440
1441 list_for_each_entry(pdd, &genpd->dev_list, list_node)
1442 if (pdd->dev == dev) {
1443 ret = -EINVAL;
1444 goto out;
1445 }
1446
1447 ret = dev_pm_get_subsys_data(dev);
1448 if (ret)
1449 goto out;
1450
1451 genpd->device_count++;
1452 genpd->max_off_time_changed = true;
1453
1454 spin_lock_irq(&dev->power.lock);
1455
1456 dev->pm_domain = &genpd->domain;
1457 if (dev->power.subsys_data->domain_data) {
1458 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1459 } else {
1460 gpd_data = gpd_data_new;
1461 dev->power.subsys_data->domain_data = &gpd_data->base;
1462 }
1463 gpd_data->refcount++;
1464 if (td)
1465 gpd_data->td = *td;
1466
1467 spin_unlock_irq(&dev->power.lock);
1468
1469 mutex_lock(&gpd_data->lock);
1470 gpd_data->base.dev = dev;
1471 list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1472 gpd_data->need_restore = genpd->status == GPD_STATE_POWER_OFF;
1473 gpd_data->td.constraint_changed = true;
1474 gpd_data->td.effective_constraint_ns = -1;
1475 mutex_unlock(&gpd_data->lock);
1476
1477 out:
1478 genpd_release_lock(genpd);
1479
1480 if (gpd_data != gpd_data_new)
1481 __pm_genpd_free_dev_data(dev, gpd_data_new);
1482
1483 return ret;
1484}
1485
1486/**
1487 * __pm_genpd_of_add_device - Add a device to an I/O PM domain.
1488 * @genpd_node: Device tree node pointer representing a PM domain to which the
1489 * the device is added to.
1490 * @dev: Device to be added.
1491 * @td: Set of PM QoS timing parameters to attach to the device.
1492 */
1493int __pm_genpd_of_add_device(struct device_node *genpd_node, struct device *dev,
1494 struct gpd_timing_data *td)
1495{
1496 struct generic_pm_domain *genpd = NULL, *gpd;
1497
1498 dev_dbg(dev, "%s()\n", __func__);
1499
1500 if (IS_ERR_OR_NULL(genpd_node) || IS_ERR_OR_NULL(dev))
1501 return -EINVAL;
1502
1503 mutex_lock(&gpd_list_lock);
1504 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1505 if (gpd->of_node == genpd_node) {
1506 genpd = gpd;
1507 break;
1508 }
1509 }
1510 mutex_unlock(&gpd_list_lock);
1511
1512 if (!genpd)
1513 return -EINVAL;
1514
1515 return __pm_genpd_add_device(genpd, dev, td);
1516}
1517
1518
1519/**
1520 * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
1521 * @domain_name: Name of the PM domain to add the device to.
1522 * @dev: Device to be added.
1523 * @td: Set of PM QoS timing parameters to attach to the device.
1524 */
1525int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
1526 struct gpd_timing_data *td)
1527{
1528 return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
1529}
1530
1531/**
1532 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1533 * @genpd: PM domain to remove the device from.
1534 * @dev: Device to be removed.
1535 */
1536int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1537 struct device *dev)
1538{
1539 struct generic_pm_domain_data *gpd_data;
1540 struct pm_domain_data *pdd;
1541 bool remove = false;
1542 int ret = 0;
1543
1544 dev_dbg(dev, "%s()\n", __func__);
1545
1546 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)
1547 || IS_ERR_OR_NULL(dev->pm_domain)
1548 || pd_to_genpd(dev->pm_domain) != genpd)
1549 return -EINVAL;
1550
1551 genpd_acquire_lock(genpd);
1552
1553 if (genpd->prepared_count > 0) {
1554 ret = -EAGAIN;
1555 goto out;
1556 }
1557
1558 genpd->device_count--;
1559 genpd->max_off_time_changed = true;
1560
1561 spin_lock_irq(&dev->power.lock);
1562
1563 dev->pm_domain = NULL;
1564 pdd = dev->power.subsys_data->domain_data;
1565 list_del_init(&pdd->list_node);
1566 gpd_data = to_gpd_data(pdd);
1567 if (--gpd_data->refcount == 0) {
1568 dev->power.subsys_data->domain_data = NULL;
1569 remove = true;
1570 }
1571
1572 spin_unlock_irq(&dev->power.lock);
1573
1574 mutex_lock(&gpd_data->lock);
1575 pdd->dev = NULL;
1576 mutex_unlock(&gpd_data->lock);
1577
1578 genpd_release_lock(genpd);
1579
1580 dev_pm_put_subsys_data(dev);
1581 if (remove)
1582 __pm_genpd_free_dev_data(dev, gpd_data);
1583
1584 return 0;
1585
1586 out:
1587 genpd_release_lock(genpd);
1588
1589 return ret;
1590}
1591
1592/**
1593 * pm_genpd_dev_need_restore - Set/unset the device's "need restore" flag.
1594 * @dev: Device to set/unset the flag for.
1595 * @val: The new value of the device's "need restore" flag.
1596 */
1597void pm_genpd_dev_need_restore(struct device *dev, bool val)
1598{
1599 struct pm_subsys_data *psd;
1600 unsigned long flags;
1601
1602 spin_lock_irqsave(&dev->power.lock, flags);
1603
1604 psd = dev_to_psd(dev);
1605 if (psd && psd->domain_data)
1606 to_gpd_data(psd->domain_data)->need_restore = val;
1607
1608 spin_unlock_irqrestore(&dev->power.lock, flags);
1609}
1610EXPORT_SYMBOL_GPL(pm_genpd_dev_need_restore);
1611
1612/**
1613 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1614 * @genpd: Master PM domain to add the subdomain to.
1615 * @subdomain: Subdomain to be added.
1616 */
1617int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1618 struct generic_pm_domain *subdomain)
1619{
1620 struct gpd_link *link;
1621 int ret = 0;
1622
1623 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1624 || genpd == subdomain)
1625 return -EINVAL;
1626
1627 start:
1628 genpd_acquire_lock(genpd);
1629 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1630
1631 if (subdomain->status != GPD_STATE_POWER_OFF
1632 && subdomain->status != GPD_STATE_ACTIVE) {
1633 mutex_unlock(&subdomain->lock);
1634 genpd_release_lock(genpd);
1635 goto start;
1636 }
1637
1638 if (genpd->status == GPD_STATE_POWER_OFF
1639 && subdomain->status != GPD_STATE_POWER_OFF) {
1640 ret = -EINVAL;
1641 goto out;
1642 }
1643
1644 list_for_each_entry(link, &genpd->master_links, master_node) {
1645 if (link->slave == subdomain && link->master == genpd) {
1646 ret = -EINVAL;
1647 goto out;
1648 }
1649 }
1650
1651 link = kzalloc(sizeof(*link), GFP_KERNEL);
1652 if (!link) {
1653 ret = -ENOMEM;
1654 goto out;
1655 }
1656 link->master = genpd;
1657 list_add_tail(&link->master_node, &genpd->master_links);
1658 link->slave = subdomain;
1659 list_add_tail(&link->slave_node, &subdomain->slave_links);
1660 if (subdomain->status != GPD_STATE_POWER_OFF)
1661 genpd_sd_counter_inc(genpd);
1662
1663 out:
1664 mutex_unlock(&subdomain->lock);
1665 genpd_release_lock(genpd);
1666
1667 return ret;
1668}
1669
1670/**
1671 * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
1672 * @master_name: Name of the master PM domain to add the subdomain to.
1673 * @subdomain_name: Name of the subdomain to be added.
1674 */
1675int pm_genpd_add_subdomain_names(const char *master_name,
1676 const char *subdomain_name)
1677{
1678 struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
1679
1680 if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
1681 return -EINVAL;
1682
1683 mutex_lock(&gpd_list_lock);
1684 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1685 if (!master && !strcmp(gpd->name, master_name))
1686 master = gpd;
1687
1688 if (!subdomain && !strcmp(gpd->name, subdomain_name))
1689 subdomain = gpd;
1690
1691 if (master && subdomain)
1692 break;
1693 }
1694 mutex_unlock(&gpd_list_lock);
1695
1696 return pm_genpd_add_subdomain(master, subdomain);
1697}
1698
1699/**
1700 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1701 * @genpd: Master PM domain to remove the subdomain from.
1702 * @subdomain: Subdomain to be removed.
1703 */
1704int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1705 struct generic_pm_domain *subdomain)
1706{
1707 struct gpd_link *link;
1708 int ret = -EINVAL;
1709
1710 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1711 return -EINVAL;
1712
1713 start:
1714 genpd_acquire_lock(genpd);
1715
1716 list_for_each_entry(link, &genpd->master_links, master_node) {
1717 if (link->slave != subdomain)
1718 continue;
1719
1720 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1721
1722 if (subdomain->status != GPD_STATE_POWER_OFF
1723 && subdomain->status != GPD_STATE_ACTIVE) {
1724 mutex_unlock(&subdomain->lock);
1725 genpd_release_lock(genpd);
1726 goto start;
1727 }
1728
1729 list_del(&link->master_node);
1730 list_del(&link->slave_node);
1731 kfree(link);
1732 if (subdomain->status != GPD_STATE_POWER_OFF)
1733 genpd_sd_counter_dec(genpd);
1734
1735 mutex_unlock(&subdomain->lock);
1736
1737 ret = 0;
1738 break;
1739 }
1740
1741 genpd_release_lock(genpd);
1742
1743 return ret;
1744}
1745
1746/**
1747 * pm_genpd_add_callbacks - Add PM domain callbacks to a given device.
1748 * @dev: Device to add the callbacks to.
1749 * @ops: Set of callbacks to add.
1750 * @td: Timing data to add to the device along with the callbacks (optional).
1751 *
1752 * Every call to this routine should be balanced with a call to
1753 * __pm_genpd_remove_callbacks() and they must not be nested.
1754 */
1755int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops,
1756 struct gpd_timing_data *td)
1757{
1758 struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
1759 int ret = 0;
1760
1761 if (!(dev && ops))
1762 return -EINVAL;
1763
1764 gpd_data_new = __pm_genpd_alloc_dev_data(dev);
1765 if (!gpd_data_new)
1766 return -ENOMEM;
1767
1768 pm_runtime_disable(dev);
1769 device_pm_lock();
1770
1771 ret = dev_pm_get_subsys_data(dev);
1772 if (ret)
1773 goto out;
1774
1775 spin_lock_irq(&dev->power.lock);
1776
1777 if (dev->power.subsys_data->domain_data) {
1778 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1779 } else {
1780 gpd_data = gpd_data_new;
1781 dev->power.subsys_data->domain_data = &gpd_data->base;
1782 }
1783 gpd_data->refcount++;
1784 gpd_data->ops = *ops;
1785 if (td)
1786 gpd_data->td = *td;
1787
1788 spin_unlock_irq(&dev->power.lock);
1789
1790 out:
1791 device_pm_unlock();
1792 pm_runtime_enable(dev);
1793
1794 if (gpd_data != gpd_data_new)
1795 __pm_genpd_free_dev_data(dev, gpd_data_new);
1796
1797 return ret;
1798}
1799EXPORT_SYMBOL_GPL(pm_genpd_add_callbacks);
1800
1801/**
1802 * __pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device.
1803 * @dev: Device to remove the callbacks from.
1804 * @clear_td: If set, clear the device's timing data too.
1805 *
1806 * This routine can only be called after pm_genpd_add_callbacks().
1807 */
1808int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td)
1809{
1810 struct generic_pm_domain_data *gpd_data = NULL;
1811 bool remove = false;
1812 int ret = 0;
1813
1814 if (!(dev && dev->power.subsys_data))
1815 return -EINVAL;
1816
1817 pm_runtime_disable(dev);
1818 device_pm_lock();
1819
1820 spin_lock_irq(&dev->power.lock);
1821
1822 if (dev->power.subsys_data->domain_data) {
1823 gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
1824 gpd_data->ops = (struct gpd_dev_ops){ NULL };
1825 if (clear_td)
1826 gpd_data->td = (struct gpd_timing_data){ 0 };
1827
1828 if (--gpd_data->refcount == 0) {
1829 dev->power.subsys_data->domain_data = NULL;
1830 remove = true;
1831 }
1832 } else {
1833 ret = -EINVAL;
1834 }
1835
1836 spin_unlock_irq(&dev->power.lock);
1837
1838 device_pm_unlock();
1839 pm_runtime_enable(dev);
1840
1841 if (ret)
1842 return ret;
1843
1844 dev_pm_put_subsys_data(dev);
1845 if (remove)
1846 __pm_genpd_free_dev_data(dev, gpd_data);
1847
1848 return 0;
1849}
1850EXPORT_SYMBOL_GPL(__pm_genpd_remove_callbacks);
1851
1852/**
1853 * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
1854 * @genpd: PM domain to be connected with cpuidle.
1855 * @state: cpuidle state this domain can disable/enable.
1856 *
1857 * Make a PM domain behave as though it contained a CPU core, that is, instead
1858 * of calling its power down routine it will enable the given cpuidle state so
1859 * that the cpuidle subsystem can power it down (if possible and desirable).
1860 */
1861int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
1862{
1863 struct cpuidle_driver *cpuidle_drv;
1864 struct gpd_cpu_data *cpu_data;
1865 struct cpuidle_state *idle_state;
1866 int ret = 0;
1867
1868 if (IS_ERR_OR_NULL(genpd) || state < 0)
1869 return -EINVAL;
1870
1871 genpd_acquire_lock(genpd);
1872
1873 if (genpd->cpu_data) {
1874 ret = -EEXIST;
1875 goto out;
1876 }
1877 cpu_data = kzalloc(sizeof(*cpu_data), GFP_KERNEL);
1878 if (!cpu_data) {
1879 ret = -ENOMEM;
1880 goto out;
1881 }
1882 cpuidle_drv = cpuidle_driver_ref();
1883 if (!cpuidle_drv) {
1884 ret = -ENODEV;
1885 goto err_drv;
1886 }
1887 if (cpuidle_drv->state_count <= state) {
1888 ret = -EINVAL;
1889 goto err;
1890 }
1891 idle_state = &cpuidle_drv->states[state];
1892 if (!idle_state->disabled) {
1893 ret = -EAGAIN;
1894 goto err;
1895 }
1896 cpu_data->idle_state = idle_state;
1897 cpu_data->saved_exit_latency = idle_state->exit_latency;
1898 genpd->cpu_data = cpu_data;
1899 genpd_recalc_cpu_exit_latency(genpd);
1900
1901 out:
1902 genpd_release_lock(genpd);
1903 return ret;
1904
1905 err:
1906 cpuidle_driver_unref();
1907
1908 err_drv:
1909 kfree(cpu_data);
1910 goto out;
1911}
1912
1913/**
1914 * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
1915 * @name: Name of the domain to connect to cpuidle.
1916 * @state: cpuidle state this domain can manipulate.
1917 */
1918int pm_genpd_name_attach_cpuidle(const char *name, int state)
1919{
1920 return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
1921}
1922
1923/**
1924 * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
1925 * @genpd: PM domain to remove the cpuidle connection from.
1926 *
1927 * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
1928 * given PM domain.
1929 */
1930int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
1931{
1932 struct gpd_cpu_data *cpu_data;
1933 struct cpuidle_state *idle_state;
1934 int ret = 0;
1935
1936 if (IS_ERR_OR_NULL(genpd))
1937 return -EINVAL;
1938
1939 genpd_acquire_lock(genpd);
1940
1941 cpu_data = genpd->cpu_data;
1942 if (!cpu_data) {
1943 ret = -ENODEV;
1944 goto out;
1945 }
1946 idle_state = cpu_data->idle_state;
1947 if (!idle_state->disabled) {
1948 ret = -EAGAIN;
1949 goto out;
1950 }
1951 idle_state->exit_latency = cpu_data->saved_exit_latency;
1952 cpuidle_driver_unref();
1953 genpd->cpu_data = NULL;
1954 kfree(cpu_data);
1955
1956 out:
1957 genpd_release_lock(genpd);
1958 return ret;
1959}
1960
1961/**
1962 * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
1963 * @name: Name of the domain to disconnect cpuidle from.
1964 */
1965int pm_genpd_name_detach_cpuidle(const char *name)
1966{
1967 return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
1968}
1969
1970/* Default device callbacks for generic PM domains. */
1971
1972/**
1973 * pm_genpd_default_save_state - Default "save device state" for PM domians.
1974 * @dev: Device to handle.
1975 */
1976static int pm_genpd_default_save_state(struct device *dev)
1977{
1978 int (*cb)(struct device *__dev);
1979
1980 cb = dev_gpd_data(dev)->ops.save_state;
1981 if (cb)
1982 return cb(dev);
1983
1984 if (dev->type && dev->type->pm)
1985 cb = dev->type->pm->runtime_suspend;
1986 else if (dev->class && dev->class->pm)
1987 cb = dev->class->pm->runtime_suspend;
1988 else if (dev->bus && dev->bus->pm)
1989 cb = dev->bus->pm->runtime_suspend;
1990 else
1991 cb = NULL;
1992
1993 if (!cb && dev->driver && dev->driver->pm)
1994 cb = dev->driver->pm->runtime_suspend;
1995
1996 return cb ? cb(dev) : 0;
1997}
1998
1999/**
2000 * pm_genpd_default_restore_state - Default PM domians "restore device state".
2001 * @dev: Device to handle.
2002 */
2003static int pm_genpd_default_restore_state(struct device *dev)
2004{
2005 int (*cb)(struct device *__dev);
2006
2007 cb = dev_gpd_data(dev)->ops.restore_state;
2008 if (cb)
2009 return cb(dev);
2010
2011 if (dev->type && dev->type->pm)
2012 cb = dev->type->pm->runtime_resume;
2013 else if (dev->class && dev->class->pm)
2014 cb = dev->class->pm->runtime_resume;
2015 else if (dev->bus && dev->bus->pm)
2016 cb = dev->bus->pm->runtime_resume;
2017 else
2018 cb = NULL;
2019
2020 if (!cb && dev->driver && dev->driver->pm)
2021 cb = dev->driver->pm->runtime_resume;
2022
2023 return cb ? cb(dev) : 0;
2024}
2025
2026#ifdef CONFIG_PM_SLEEP
2027
2028/**
2029 * pm_genpd_default_suspend - Default "device suspend" for PM domians.
2030 * @dev: Device to handle.
2031 */
2032static int pm_genpd_default_suspend(struct device *dev)
2033{
2034 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend;
2035
2036 return cb ? cb(dev) : pm_generic_suspend(dev);
2037}
2038
2039/**
2040 * pm_genpd_default_suspend_late - Default "late device suspend" for PM domians.
2041 * @dev: Device to handle.
2042 */
2043static int pm_genpd_default_suspend_late(struct device *dev)
2044{
2045 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend_late;
2046
2047 return cb ? cb(dev) : pm_generic_suspend_late(dev);
2048}
2049
2050/**
2051 * pm_genpd_default_resume_early - Default "early device resume" for PM domians.
2052 * @dev: Device to handle.
2053 */
2054static int pm_genpd_default_resume_early(struct device *dev)
2055{
2056 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume_early;
2057
2058 return cb ? cb(dev) : pm_generic_resume_early(dev);
2059}
2060
2061/**
2062 * pm_genpd_default_resume - Default "device resume" for PM domians.
2063 * @dev: Device to handle.
2064 */
2065static int pm_genpd_default_resume(struct device *dev)
2066{
2067 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume;
2068
2069 return cb ? cb(dev) : pm_generic_resume(dev);
2070}
2071
2072/**
2073 * pm_genpd_default_freeze - Default "device freeze" for PM domians.
2074 * @dev: Device to handle.
2075 */
2076static int pm_genpd_default_freeze(struct device *dev)
2077{
2078 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze;
2079
2080 return cb ? cb(dev) : pm_generic_freeze(dev);
2081}
2082
2083/**
2084 * pm_genpd_default_freeze_late - Default "late device freeze" for PM domians.
2085 * @dev: Device to handle.
2086 */
2087static int pm_genpd_default_freeze_late(struct device *dev)
2088{
2089 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late;
2090
2091 return cb ? cb(dev) : pm_generic_freeze_late(dev);
2092}
2093
2094/**
2095 * pm_genpd_default_thaw_early - Default "early device thaw" for PM domians.
2096 * @dev: Device to handle.
2097 */
2098static int pm_genpd_default_thaw_early(struct device *dev)
2099{
2100 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early;
2101
2102 return cb ? cb(dev) : pm_generic_thaw_early(dev);
2103}
2104
2105/**
2106 * pm_genpd_default_thaw - Default "device thaw" for PM domians.
2107 * @dev: Device to handle.
2108 */
2109static int pm_genpd_default_thaw(struct device *dev)
2110{
2111 int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw;
2112
2113 return cb ? cb(dev) : pm_generic_thaw(dev);
2114}
2115
2116#else /* !CONFIG_PM_SLEEP */
2117
2118#define pm_genpd_default_suspend NULL
2119#define pm_genpd_default_suspend_late NULL
2120#define pm_genpd_default_resume_early NULL
2121#define pm_genpd_default_resume NULL
2122#define pm_genpd_default_freeze NULL
2123#define pm_genpd_default_freeze_late NULL
2124#define pm_genpd_default_thaw_early NULL
2125#define pm_genpd_default_thaw NULL
2126
2127#endif /* !CONFIG_PM_SLEEP */
2128
2129/**
2130 * pm_genpd_init - Initialize a generic I/O PM domain object.
2131 * @genpd: PM domain object to initialize.
2132 * @gov: PM domain governor to associate with the domain (may be NULL).
2133 * @is_off: Initial value of the domain's power_is_off field.
2134 */
2135void pm_genpd_init(struct generic_pm_domain *genpd,
2136 struct dev_power_governor *gov, bool is_off)
2137{
2138 if (IS_ERR_OR_NULL(genpd))
2139 return;
2140
2141 INIT_LIST_HEAD(&genpd->master_links);
2142 INIT_LIST_HEAD(&genpd->slave_links);
2143 INIT_LIST_HEAD(&genpd->dev_list);
2144 mutex_init(&genpd->lock);
2145 genpd->gov = gov;
2146 INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
2147 genpd->in_progress = 0;
2148 atomic_set(&genpd->sd_count, 0);
2149 genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
2150 init_waitqueue_head(&genpd->status_wait_queue);
2151 genpd->poweroff_task = NULL;
2152 genpd->resume_count = 0;
2153 genpd->device_count = 0;
2154 genpd->max_off_time_ns = -1;
2155 genpd->max_off_time_changed = true;
2156 genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
2157 genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
2158 genpd->domain.ops.prepare = pm_genpd_prepare;
2159 genpd->domain.ops.suspend = pm_genpd_suspend;
2160 genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
2161 genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
2162 genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
2163 genpd->domain.ops.resume_early = pm_genpd_resume_early;
2164 genpd->domain.ops.resume = pm_genpd_resume;
2165 genpd->domain.ops.freeze = pm_genpd_freeze;
2166 genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
2167 genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
2168 genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
2169 genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
2170 genpd->domain.ops.thaw = pm_genpd_thaw;
2171 genpd->domain.ops.poweroff = pm_genpd_suspend;
2172 genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
2173 genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
2174 genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
2175 genpd->domain.ops.restore_early = pm_genpd_resume_early;
2176 genpd->domain.ops.restore = pm_genpd_resume;
2177 genpd->domain.ops.complete = pm_genpd_complete;
2178 genpd->dev_ops.save_state = pm_genpd_default_save_state;
2179 genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
2180 genpd->dev_ops.suspend = pm_genpd_default_suspend;
2181 genpd->dev_ops.suspend_late = pm_genpd_default_suspend_late;
2182 genpd->dev_ops.resume_early = pm_genpd_default_resume_early;
2183 genpd->dev_ops.resume = pm_genpd_default_resume;
2184 genpd->dev_ops.freeze = pm_genpd_default_freeze;
2185 genpd->dev_ops.freeze_late = pm_genpd_default_freeze_late;
2186 genpd->dev_ops.thaw_early = pm_genpd_default_thaw_early;
2187 genpd->dev_ops.thaw = pm_genpd_default_thaw;
2188 mutex_lock(&gpd_list_lock);
2189 list_add(&genpd->gpd_list_node, &gpd_list);
2190 mutex_unlock(&gpd_list_lock);
2191}