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