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