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