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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * drivers/base/power/main.c - Where the driver meets power management.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 *
8 * The driver model core calls device_pm_add() when a device is registered.
9 * This will initialize the embedded device_pm_info object in the device
10 * and add it to the list of power-controlled devices. sysfs entries for
11 * controlling device power management will also be added.
12 *
13 * A separate list is used for keeping track of power info, because the power
14 * domain dependencies may differ from the ancestral dependencies that the
15 * subsystem list maintains.
16 */
17
18#define pr_fmt(fmt) "PM: " fmt
19#define dev_fmt pr_fmt
20
21#include <linux/device.h>
22#include <linux/export.h>
23#include <linux/mutex.h>
24#include <linux/pm.h>
25#include <linux/pm_runtime.h>
26#include <linux/pm-trace.h>
27#include <linux/pm_wakeirq.h>
28#include <linux/interrupt.h>
29#include <linux/sched.h>
30#include <linux/sched/debug.h>
31#include <linux/async.h>
32#include <linux/suspend.h>
33#include <trace/events/power.h>
34#include <linux/cpufreq.h>
35#include <linux/cpuidle.h>
36#include <linux/devfreq.h>
37#include <linux/timer.h>
38
39#include "../base.h"
40#include "power.h"
41
42typedef int (*pm_callback_t)(struct device *);
43
44#define list_for_each_entry_rcu_locked(pos, head, member) \
45 list_for_each_entry_rcu(pos, head, member, \
46 device_links_read_lock_held())
47
48/*
49 * The entries in the dpm_list list are in a depth first order, simply
50 * because children are guaranteed to be discovered after parents, and
51 * are inserted at the back of the list on discovery.
52 *
53 * Since device_pm_add() may be called with a device lock held,
54 * we must never try to acquire a device lock while holding
55 * dpm_list_mutex.
56 */
57
58LIST_HEAD(dpm_list);
59static LIST_HEAD(dpm_prepared_list);
60static LIST_HEAD(dpm_suspended_list);
61static LIST_HEAD(dpm_late_early_list);
62static LIST_HEAD(dpm_noirq_list);
63
64struct suspend_stats suspend_stats;
65static DEFINE_MUTEX(dpm_list_mtx);
66static pm_message_t pm_transition;
67
68static int async_error;
69
70static const char *pm_verb(int event)
71{
72 switch (event) {
73 case PM_EVENT_SUSPEND:
74 return "suspend";
75 case PM_EVENT_RESUME:
76 return "resume";
77 case PM_EVENT_FREEZE:
78 return "freeze";
79 case PM_EVENT_QUIESCE:
80 return "quiesce";
81 case PM_EVENT_HIBERNATE:
82 return "hibernate";
83 case PM_EVENT_THAW:
84 return "thaw";
85 case PM_EVENT_RESTORE:
86 return "restore";
87 case PM_EVENT_RECOVER:
88 return "recover";
89 default:
90 return "(unknown PM event)";
91 }
92}
93
94/**
95 * device_pm_sleep_init - Initialize system suspend-related device fields.
96 * @dev: Device object being initialized.
97 */
98void device_pm_sleep_init(struct device *dev)
99{
100 dev->power.is_prepared = false;
101 dev->power.is_suspended = false;
102 dev->power.is_noirq_suspended = false;
103 dev->power.is_late_suspended = false;
104 init_completion(&dev->power.completion);
105 complete_all(&dev->power.completion);
106 dev->power.wakeup = NULL;
107 INIT_LIST_HEAD(&dev->power.entry);
108}
109
110/**
111 * device_pm_lock - Lock the list of active devices used by the PM core.
112 */
113void device_pm_lock(void)
114{
115 mutex_lock(&dpm_list_mtx);
116}
117
118/**
119 * device_pm_unlock - Unlock the list of active devices used by the PM core.
120 */
121void device_pm_unlock(void)
122{
123 mutex_unlock(&dpm_list_mtx);
124}
125
126/**
127 * device_pm_add - Add a device to the PM core's list of active devices.
128 * @dev: Device to add to the list.
129 */
130void device_pm_add(struct device *dev)
131{
132 /* Skip PM setup/initialization. */
133 if (device_pm_not_required(dev))
134 return;
135
136 pr_debug("Adding info for %s:%s\n",
137 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
138 device_pm_check_callbacks(dev);
139 mutex_lock(&dpm_list_mtx);
140 if (dev->parent && dev->parent->power.is_prepared)
141 dev_warn(dev, "parent %s should not be sleeping\n",
142 dev_name(dev->parent));
143 list_add_tail(&dev->power.entry, &dpm_list);
144 dev->power.in_dpm_list = true;
145 mutex_unlock(&dpm_list_mtx);
146}
147
148/**
149 * device_pm_remove - Remove a device from the PM core's list of active devices.
150 * @dev: Device to be removed from the list.
151 */
152void device_pm_remove(struct device *dev)
153{
154 if (device_pm_not_required(dev))
155 return;
156
157 pr_debug("Removing info for %s:%s\n",
158 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
159 complete_all(&dev->power.completion);
160 mutex_lock(&dpm_list_mtx);
161 list_del_init(&dev->power.entry);
162 dev->power.in_dpm_list = false;
163 mutex_unlock(&dpm_list_mtx);
164 device_wakeup_disable(dev);
165 pm_runtime_remove(dev);
166 device_pm_check_callbacks(dev);
167}
168
169/**
170 * device_pm_move_before - Move device in the PM core's list of active devices.
171 * @deva: Device to move in dpm_list.
172 * @devb: Device @deva should come before.
173 */
174void device_pm_move_before(struct device *deva, struct device *devb)
175{
176 pr_debug("Moving %s:%s before %s:%s\n",
177 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
178 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
179 /* Delete deva from dpm_list and reinsert before devb. */
180 list_move_tail(&deva->power.entry, &devb->power.entry);
181}
182
183/**
184 * device_pm_move_after - Move device in the PM core's list of active devices.
185 * @deva: Device to move in dpm_list.
186 * @devb: Device @deva should come after.
187 */
188void device_pm_move_after(struct device *deva, struct device *devb)
189{
190 pr_debug("Moving %s:%s after %s:%s\n",
191 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
192 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
193 /* Delete deva from dpm_list and reinsert after devb. */
194 list_move(&deva->power.entry, &devb->power.entry);
195}
196
197/**
198 * device_pm_move_last - Move device to end of the PM core's list of devices.
199 * @dev: Device to move in dpm_list.
200 */
201void device_pm_move_last(struct device *dev)
202{
203 pr_debug("Moving %s:%s to end of list\n",
204 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
205 list_move_tail(&dev->power.entry, &dpm_list);
206}
207
208static ktime_t initcall_debug_start(struct device *dev, void *cb)
209{
210 if (!pm_print_times_enabled)
211 return 0;
212
213 dev_info(dev, "calling %pS @ %i, parent: %s\n", cb,
214 task_pid_nr(current),
215 dev->parent ? dev_name(dev->parent) : "none");
216 return ktime_get();
217}
218
219static void initcall_debug_report(struct device *dev, ktime_t calltime,
220 void *cb, int error)
221{
222 ktime_t rettime;
223
224 if (!pm_print_times_enabled)
225 return;
226
227 rettime = ktime_get();
228 dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error,
229 (unsigned long long)ktime_us_delta(rettime, calltime));
230}
231
232/**
233 * dpm_wait - Wait for a PM operation to complete.
234 * @dev: Device to wait for.
235 * @async: If unset, wait only if the device's power.async_suspend flag is set.
236 */
237static void dpm_wait(struct device *dev, bool async)
238{
239 if (!dev)
240 return;
241
242 if (async || (pm_async_enabled && dev->power.async_suspend))
243 wait_for_completion(&dev->power.completion);
244}
245
246static int dpm_wait_fn(struct device *dev, void *async_ptr)
247{
248 dpm_wait(dev, *((bool *)async_ptr));
249 return 0;
250}
251
252static void dpm_wait_for_children(struct device *dev, bool async)
253{
254 device_for_each_child(dev, &async, dpm_wait_fn);
255}
256
257static void dpm_wait_for_suppliers(struct device *dev, bool async)
258{
259 struct device_link *link;
260 int idx;
261
262 idx = device_links_read_lock();
263
264 /*
265 * If the supplier goes away right after we've checked the link to it,
266 * we'll wait for its completion to change the state, but that's fine,
267 * because the only things that will block as a result are the SRCU
268 * callbacks freeing the link objects for the links in the list we're
269 * walking.
270 */
271 list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
272 if (READ_ONCE(link->status) != DL_STATE_DORMANT)
273 dpm_wait(link->supplier, async);
274
275 device_links_read_unlock(idx);
276}
277
278static bool dpm_wait_for_superior(struct device *dev, bool async)
279{
280 struct device *parent;
281
282 /*
283 * If the device is resumed asynchronously and the parent's callback
284 * deletes both the device and the parent itself, the parent object may
285 * be freed while this function is running, so avoid that by reference
286 * counting the parent once more unless the device has been deleted
287 * already (in which case return right away).
288 */
289 mutex_lock(&dpm_list_mtx);
290
291 if (!device_pm_initialized(dev)) {
292 mutex_unlock(&dpm_list_mtx);
293 return false;
294 }
295
296 parent = get_device(dev->parent);
297
298 mutex_unlock(&dpm_list_mtx);
299
300 dpm_wait(parent, async);
301 put_device(parent);
302
303 dpm_wait_for_suppliers(dev, async);
304
305 /*
306 * If the parent's callback has deleted the device, attempting to resume
307 * it would be invalid, so avoid doing that then.
308 */
309 return device_pm_initialized(dev);
310}
311
312static void dpm_wait_for_consumers(struct device *dev, bool async)
313{
314 struct device_link *link;
315 int idx;
316
317 idx = device_links_read_lock();
318
319 /*
320 * The status of a device link can only be changed from "dormant" by a
321 * probe, but that cannot happen during system suspend/resume. In
322 * theory it can change to "dormant" at that time, but then it is
323 * reasonable to wait for the target device anyway (eg. if it goes
324 * away, it's better to wait for it to go away completely and then
325 * continue instead of trying to continue in parallel with its
326 * unregistration).
327 */
328 list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node)
329 if (READ_ONCE(link->status) != DL_STATE_DORMANT)
330 dpm_wait(link->consumer, async);
331
332 device_links_read_unlock(idx);
333}
334
335static void dpm_wait_for_subordinate(struct device *dev, bool async)
336{
337 dpm_wait_for_children(dev, async);
338 dpm_wait_for_consumers(dev, async);
339}
340
341/**
342 * pm_op - Return the PM operation appropriate for given PM event.
343 * @ops: PM operations to choose from.
344 * @state: PM transition of the system being carried out.
345 */
346static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
347{
348 switch (state.event) {
349#ifdef CONFIG_SUSPEND
350 case PM_EVENT_SUSPEND:
351 return ops->suspend;
352 case PM_EVENT_RESUME:
353 return ops->resume;
354#endif /* CONFIG_SUSPEND */
355#ifdef CONFIG_HIBERNATE_CALLBACKS
356 case PM_EVENT_FREEZE:
357 case PM_EVENT_QUIESCE:
358 return ops->freeze;
359 case PM_EVENT_HIBERNATE:
360 return ops->poweroff;
361 case PM_EVENT_THAW:
362 case PM_EVENT_RECOVER:
363 return ops->thaw;
364 case PM_EVENT_RESTORE:
365 return ops->restore;
366#endif /* CONFIG_HIBERNATE_CALLBACKS */
367 }
368
369 return NULL;
370}
371
372/**
373 * pm_late_early_op - Return the PM operation appropriate for given PM event.
374 * @ops: PM operations to choose from.
375 * @state: PM transition of the system being carried out.
376 *
377 * Runtime PM is disabled for @dev while this function is being executed.
378 */
379static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
380 pm_message_t state)
381{
382 switch (state.event) {
383#ifdef CONFIG_SUSPEND
384 case PM_EVENT_SUSPEND:
385 return ops->suspend_late;
386 case PM_EVENT_RESUME:
387 return ops->resume_early;
388#endif /* CONFIG_SUSPEND */
389#ifdef CONFIG_HIBERNATE_CALLBACKS
390 case PM_EVENT_FREEZE:
391 case PM_EVENT_QUIESCE:
392 return ops->freeze_late;
393 case PM_EVENT_HIBERNATE:
394 return ops->poweroff_late;
395 case PM_EVENT_THAW:
396 case PM_EVENT_RECOVER:
397 return ops->thaw_early;
398 case PM_EVENT_RESTORE:
399 return ops->restore_early;
400#endif /* CONFIG_HIBERNATE_CALLBACKS */
401 }
402
403 return NULL;
404}
405
406/**
407 * pm_noirq_op - Return the PM operation appropriate for given PM event.
408 * @ops: PM operations to choose from.
409 * @state: PM transition of the system being carried out.
410 *
411 * The driver of @dev will not receive interrupts while this function is being
412 * executed.
413 */
414static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
415{
416 switch (state.event) {
417#ifdef CONFIG_SUSPEND
418 case PM_EVENT_SUSPEND:
419 return ops->suspend_noirq;
420 case PM_EVENT_RESUME:
421 return ops->resume_noirq;
422#endif /* CONFIG_SUSPEND */
423#ifdef CONFIG_HIBERNATE_CALLBACKS
424 case PM_EVENT_FREEZE:
425 case PM_EVENT_QUIESCE:
426 return ops->freeze_noirq;
427 case PM_EVENT_HIBERNATE:
428 return ops->poweroff_noirq;
429 case PM_EVENT_THAW:
430 case PM_EVENT_RECOVER:
431 return ops->thaw_noirq;
432 case PM_EVENT_RESTORE:
433 return ops->restore_noirq;
434#endif /* CONFIG_HIBERNATE_CALLBACKS */
435 }
436
437 return NULL;
438}
439
440static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info)
441{
442 dev_dbg(dev, "%s%s%s driver flags: %x\n", info, pm_verb(state.event),
443 ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
444 ", may wakeup" : "", dev->power.driver_flags);
445}
446
447static void pm_dev_err(struct device *dev, pm_message_t state, const char *info,
448 int error)
449{
450 dev_err(dev, "failed to %s%s: error %d\n", pm_verb(state.event), info,
451 error);
452}
453
454static void dpm_show_time(ktime_t starttime, pm_message_t state, int error,
455 const char *info)
456{
457 ktime_t calltime;
458 u64 usecs64;
459 int usecs;
460
461 calltime = ktime_get();
462 usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
463 do_div(usecs64, NSEC_PER_USEC);
464 usecs = usecs64;
465 if (usecs == 0)
466 usecs = 1;
467
468 pm_pr_dbg("%s%s%s of devices %s after %ld.%03ld msecs\n",
469 info ?: "", info ? " " : "", pm_verb(state.event),
470 error ? "aborted" : "complete",
471 usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
472}
473
474static int dpm_run_callback(pm_callback_t cb, struct device *dev,
475 pm_message_t state, const char *info)
476{
477 ktime_t calltime;
478 int error;
479
480 if (!cb)
481 return 0;
482
483 calltime = initcall_debug_start(dev, cb);
484
485 pm_dev_dbg(dev, state, info);
486 trace_device_pm_callback_start(dev, info, state.event);
487 error = cb(dev);
488 trace_device_pm_callback_end(dev, error);
489 suspend_report_result(cb, error);
490
491 initcall_debug_report(dev, calltime, cb, error);
492
493 return error;
494}
495
496#ifdef CONFIG_DPM_WATCHDOG
497struct dpm_watchdog {
498 struct device *dev;
499 struct task_struct *tsk;
500 struct timer_list timer;
501};
502
503#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
504 struct dpm_watchdog wd
505
506/**
507 * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
508 * @t: The timer that PM watchdog depends on.
509 *
510 * Called when a driver has timed out suspending or resuming.
511 * There's not much we can do here to recover so panic() to
512 * capture a crash-dump in pstore.
513 */
514static void dpm_watchdog_handler(struct timer_list *t)
515{
516 struct dpm_watchdog *wd = from_timer(wd, t, timer);
517
518 dev_emerg(wd->dev, "**** DPM device timeout ****\n");
519 show_stack(wd->tsk, NULL, KERN_EMERG);
520 panic("%s %s: unrecoverable failure\n",
521 dev_driver_string(wd->dev), dev_name(wd->dev));
522}
523
524/**
525 * dpm_watchdog_set - Enable pm watchdog for given device.
526 * @wd: Watchdog. Must be allocated on the stack.
527 * @dev: Device to handle.
528 */
529static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
530{
531 struct timer_list *timer = &wd->timer;
532
533 wd->dev = dev;
534 wd->tsk = current;
535
536 timer_setup_on_stack(timer, dpm_watchdog_handler, 0);
537 /* use same timeout value for both suspend and resume */
538 timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
539 add_timer(timer);
540}
541
542/**
543 * dpm_watchdog_clear - Disable suspend/resume watchdog.
544 * @wd: Watchdog to disable.
545 */
546static void dpm_watchdog_clear(struct dpm_watchdog *wd)
547{
548 struct timer_list *timer = &wd->timer;
549
550 del_timer_sync(timer);
551 destroy_timer_on_stack(timer);
552}
553#else
554#define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
555#define dpm_watchdog_set(x, y)
556#define dpm_watchdog_clear(x)
557#endif
558
559/*------------------------- Resume routines -------------------------*/
560
561/**
562 * dev_pm_skip_resume - System-wide device resume optimization check.
563 * @dev: Target device.
564 *
565 * Return:
566 * - %false if the transition under way is RESTORE.
567 * - Return value of dev_pm_skip_suspend() if the transition under way is THAW.
568 * - The logical negation of %power.must_resume otherwise (that is, when the
569 * transition under way is RESUME).
570 */
571bool dev_pm_skip_resume(struct device *dev)
572{
573 if (pm_transition.event == PM_EVENT_RESTORE)
574 return false;
575
576 if (pm_transition.event == PM_EVENT_THAW)
577 return dev_pm_skip_suspend(dev);
578
579 return !dev->power.must_resume;
580}
581
582/**
583 * device_resume_noirq - Execute a "noirq resume" callback for given device.
584 * @dev: Device to handle.
585 * @state: PM transition of the system being carried out.
586 * @async: If true, the device is being resumed asynchronously.
587 *
588 * The driver of @dev will not receive interrupts while this function is being
589 * executed.
590 */
591static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
592{
593 pm_callback_t callback = NULL;
594 const char *info = NULL;
595 bool skip_resume;
596 int error = 0;
597
598 TRACE_DEVICE(dev);
599 TRACE_RESUME(0);
600
601 if (dev->power.syscore || dev->power.direct_complete)
602 goto Out;
603
604 if (!dev->power.is_noirq_suspended)
605 goto Out;
606
607 if (!dpm_wait_for_superior(dev, async))
608 goto Out;
609
610 skip_resume = dev_pm_skip_resume(dev);
611 /*
612 * If the driver callback is skipped below or by the middle layer
613 * callback and device_resume_early() also skips the driver callback for
614 * this device later, it needs to appear as "suspended" to PM-runtime,
615 * so change its status accordingly.
616 *
617 * Otherwise, the device is going to be resumed, so set its PM-runtime
618 * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set
619 * to avoid confusing drivers that don't use it.
620 */
621 if (skip_resume)
622 pm_runtime_set_suspended(dev);
623 else if (dev_pm_skip_suspend(dev))
624 pm_runtime_set_active(dev);
625
626 if (dev->pm_domain) {
627 info = "noirq power domain ";
628 callback = pm_noirq_op(&dev->pm_domain->ops, state);
629 } else if (dev->type && dev->type->pm) {
630 info = "noirq type ";
631 callback = pm_noirq_op(dev->type->pm, state);
632 } else if (dev->class && dev->class->pm) {
633 info = "noirq class ";
634 callback = pm_noirq_op(dev->class->pm, state);
635 } else if (dev->bus && dev->bus->pm) {
636 info = "noirq bus ";
637 callback = pm_noirq_op(dev->bus->pm, state);
638 }
639 if (callback)
640 goto Run;
641
642 if (skip_resume)
643 goto Skip;
644
645 if (dev->driver && dev->driver->pm) {
646 info = "noirq driver ";
647 callback = pm_noirq_op(dev->driver->pm, state);
648 }
649
650Run:
651 error = dpm_run_callback(callback, dev, state, info);
652
653Skip:
654 dev->power.is_noirq_suspended = false;
655
656Out:
657 complete_all(&dev->power.completion);
658 TRACE_RESUME(error);
659 return error;
660}
661
662static bool is_async(struct device *dev)
663{
664 return dev->power.async_suspend && pm_async_enabled
665 && !pm_trace_is_enabled();
666}
667
668static bool dpm_async_fn(struct device *dev, async_func_t func)
669{
670 reinit_completion(&dev->power.completion);
671
672 if (is_async(dev)) {
673 get_device(dev);
674 async_schedule_dev(func, dev);
675 return true;
676 }
677
678 return false;
679}
680
681static void async_resume_noirq(void *data, async_cookie_t cookie)
682{
683 struct device *dev = (struct device *)data;
684 int error;
685
686 error = device_resume_noirq(dev, pm_transition, true);
687 if (error)
688 pm_dev_err(dev, pm_transition, " async", error);
689
690 put_device(dev);
691}
692
693static void dpm_noirq_resume_devices(pm_message_t state)
694{
695 struct device *dev;
696 ktime_t starttime = ktime_get();
697
698 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
699 mutex_lock(&dpm_list_mtx);
700 pm_transition = state;
701
702 /*
703 * Advanced the async threads upfront,
704 * in case the starting of async threads is
705 * delayed by non-async resuming devices.
706 */
707 list_for_each_entry(dev, &dpm_noirq_list, power.entry)
708 dpm_async_fn(dev, async_resume_noirq);
709
710 while (!list_empty(&dpm_noirq_list)) {
711 dev = to_device(dpm_noirq_list.next);
712 get_device(dev);
713 list_move_tail(&dev->power.entry, &dpm_late_early_list);
714 mutex_unlock(&dpm_list_mtx);
715
716 if (!is_async(dev)) {
717 int error;
718
719 error = device_resume_noirq(dev, state, false);
720 if (error) {
721 suspend_stats.failed_resume_noirq++;
722 dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
723 dpm_save_failed_dev(dev_name(dev));
724 pm_dev_err(dev, state, " noirq", error);
725 }
726 }
727
728 mutex_lock(&dpm_list_mtx);
729 put_device(dev);
730 }
731 mutex_unlock(&dpm_list_mtx);
732 async_synchronize_full();
733 dpm_show_time(starttime, state, 0, "noirq");
734 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
735}
736
737/**
738 * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
739 * @state: PM transition of the system being carried out.
740 *
741 * Invoke the "noirq" resume callbacks for all devices in dpm_noirq_list and
742 * allow device drivers' interrupt handlers to be called.
743 */
744void dpm_resume_noirq(pm_message_t state)
745{
746 dpm_noirq_resume_devices(state);
747
748 resume_device_irqs();
749 device_wakeup_disarm_wake_irqs();
750
751 cpuidle_resume();
752}
753
754/**
755 * device_resume_early - Execute an "early resume" callback for given device.
756 * @dev: Device to handle.
757 * @state: PM transition of the system being carried out.
758 * @async: If true, the device is being resumed asynchronously.
759 *
760 * Runtime PM is disabled for @dev while this function is being executed.
761 */
762static int device_resume_early(struct device *dev, pm_message_t state, bool async)
763{
764 pm_callback_t callback = NULL;
765 const char *info = NULL;
766 int error = 0;
767
768 TRACE_DEVICE(dev);
769 TRACE_RESUME(0);
770
771 if (dev->power.syscore || dev->power.direct_complete)
772 goto Out;
773
774 if (!dev->power.is_late_suspended)
775 goto Out;
776
777 if (!dpm_wait_for_superior(dev, async))
778 goto Out;
779
780 if (dev->pm_domain) {
781 info = "early power domain ";
782 callback = pm_late_early_op(&dev->pm_domain->ops, state);
783 } else if (dev->type && dev->type->pm) {
784 info = "early type ";
785 callback = pm_late_early_op(dev->type->pm, state);
786 } else if (dev->class && dev->class->pm) {
787 info = "early class ";
788 callback = pm_late_early_op(dev->class->pm, state);
789 } else if (dev->bus && dev->bus->pm) {
790 info = "early bus ";
791 callback = pm_late_early_op(dev->bus->pm, state);
792 }
793 if (callback)
794 goto Run;
795
796 if (dev_pm_skip_resume(dev))
797 goto Skip;
798
799 if (dev->driver && dev->driver->pm) {
800 info = "early driver ";
801 callback = pm_late_early_op(dev->driver->pm, state);
802 }
803
804Run:
805 error = dpm_run_callback(callback, dev, state, info);
806
807Skip:
808 dev->power.is_late_suspended = false;
809
810Out:
811 TRACE_RESUME(error);
812
813 pm_runtime_enable(dev);
814 complete_all(&dev->power.completion);
815 return error;
816}
817
818static void async_resume_early(void *data, async_cookie_t cookie)
819{
820 struct device *dev = (struct device *)data;
821 int error;
822
823 error = device_resume_early(dev, pm_transition, true);
824 if (error)
825 pm_dev_err(dev, pm_transition, " async", error);
826
827 put_device(dev);
828}
829
830/**
831 * dpm_resume_early - Execute "early resume" callbacks for all devices.
832 * @state: PM transition of the system being carried out.
833 */
834void dpm_resume_early(pm_message_t state)
835{
836 struct device *dev;
837 ktime_t starttime = ktime_get();
838
839 trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
840 mutex_lock(&dpm_list_mtx);
841 pm_transition = state;
842
843 /*
844 * Advanced the async threads upfront,
845 * in case the starting of async threads is
846 * delayed by non-async resuming devices.
847 */
848 list_for_each_entry(dev, &dpm_late_early_list, power.entry)
849 dpm_async_fn(dev, async_resume_early);
850
851 while (!list_empty(&dpm_late_early_list)) {
852 dev = to_device(dpm_late_early_list.next);
853 get_device(dev);
854 list_move_tail(&dev->power.entry, &dpm_suspended_list);
855 mutex_unlock(&dpm_list_mtx);
856
857 if (!is_async(dev)) {
858 int error;
859
860 error = device_resume_early(dev, state, false);
861 if (error) {
862 suspend_stats.failed_resume_early++;
863 dpm_save_failed_step(SUSPEND_RESUME_EARLY);
864 dpm_save_failed_dev(dev_name(dev));
865 pm_dev_err(dev, state, " early", error);
866 }
867 }
868 mutex_lock(&dpm_list_mtx);
869 put_device(dev);
870 }
871 mutex_unlock(&dpm_list_mtx);
872 async_synchronize_full();
873 dpm_show_time(starttime, state, 0, "early");
874 trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
875}
876
877/**
878 * dpm_resume_start - Execute "noirq" and "early" device callbacks.
879 * @state: PM transition of the system being carried out.
880 */
881void dpm_resume_start(pm_message_t state)
882{
883 dpm_resume_noirq(state);
884 dpm_resume_early(state);
885}
886EXPORT_SYMBOL_GPL(dpm_resume_start);
887
888/**
889 * device_resume - Execute "resume" callbacks for given device.
890 * @dev: Device to handle.
891 * @state: PM transition of the system being carried out.
892 * @async: If true, the device is being resumed asynchronously.
893 */
894static int device_resume(struct device *dev, pm_message_t state, bool async)
895{
896 pm_callback_t callback = NULL;
897 const char *info = NULL;
898 int error = 0;
899 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
900
901 TRACE_DEVICE(dev);
902 TRACE_RESUME(0);
903
904 if (dev->power.syscore)
905 goto Complete;
906
907 if (dev->power.direct_complete) {
908 /* Match the pm_runtime_disable() in __device_suspend(). */
909 pm_runtime_enable(dev);
910 goto Complete;
911 }
912
913 if (!dpm_wait_for_superior(dev, async))
914 goto Complete;
915
916 dpm_watchdog_set(&wd, dev);
917 device_lock(dev);
918
919 /*
920 * This is a fib. But we'll allow new children to be added below
921 * a resumed device, even if the device hasn't been completed yet.
922 */
923 dev->power.is_prepared = false;
924
925 if (!dev->power.is_suspended)
926 goto Unlock;
927
928 if (dev->pm_domain) {
929 info = "power domain ";
930 callback = pm_op(&dev->pm_domain->ops, state);
931 goto Driver;
932 }
933
934 if (dev->type && dev->type->pm) {
935 info = "type ";
936 callback = pm_op(dev->type->pm, state);
937 goto Driver;
938 }
939
940 if (dev->class && dev->class->pm) {
941 info = "class ";
942 callback = pm_op(dev->class->pm, state);
943 goto Driver;
944 }
945
946 if (dev->bus) {
947 if (dev->bus->pm) {
948 info = "bus ";
949 callback = pm_op(dev->bus->pm, state);
950 } else if (dev->bus->resume) {
951 info = "legacy bus ";
952 callback = dev->bus->resume;
953 goto End;
954 }
955 }
956
957 Driver:
958 if (!callback && dev->driver && dev->driver->pm) {
959 info = "driver ";
960 callback = pm_op(dev->driver->pm, state);
961 }
962
963 End:
964 error = dpm_run_callback(callback, dev, state, info);
965 dev->power.is_suspended = false;
966
967 Unlock:
968 device_unlock(dev);
969 dpm_watchdog_clear(&wd);
970
971 Complete:
972 complete_all(&dev->power.completion);
973
974 TRACE_RESUME(error);
975
976 return error;
977}
978
979static void async_resume(void *data, async_cookie_t cookie)
980{
981 struct device *dev = (struct device *)data;
982 int error;
983
984 error = device_resume(dev, pm_transition, true);
985 if (error)
986 pm_dev_err(dev, pm_transition, " async", error);
987 put_device(dev);
988}
989
990/**
991 * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
992 * @state: PM transition of the system being carried out.
993 *
994 * Execute the appropriate "resume" callback for all devices whose status
995 * indicates that they are suspended.
996 */
997void dpm_resume(pm_message_t state)
998{
999 struct device *dev;
1000 ktime_t starttime = ktime_get();
1001
1002 trace_suspend_resume(TPS("dpm_resume"), state.event, true);
1003 might_sleep();
1004
1005 mutex_lock(&dpm_list_mtx);
1006 pm_transition = state;
1007 async_error = 0;
1008
1009 list_for_each_entry(dev, &dpm_suspended_list, power.entry)
1010 dpm_async_fn(dev, async_resume);
1011
1012 while (!list_empty(&dpm_suspended_list)) {
1013 dev = to_device(dpm_suspended_list.next);
1014 get_device(dev);
1015 if (!is_async(dev)) {
1016 int error;
1017
1018 mutex_unlock(&dpm_list_mtx);
1019
1020 error = device_resume(dev, state, false);
1021 if (error) {
1022 suspend_stats.failed_resume++;
1023 dpm_save_failed_step(SUSPEND_RESUME);
1024 dpm_save_failed_dev(dev_name(dev));
1025 pm_dev_err(dev, state, "", error);
1026 }
1027
1028 mutex_lock(&dpm_list_mtx);
1029 }
1030 if (!list_empty(&dev->power.entry))
1031 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1032 put_device(dev);
1033 }
1034 mutex_unlock(&dpm_list_mtx);
1035 async_synchronize_full();
1036 dpm_show_time(starttime, state, 0, NULL);
1037
1038 cpufreq_resume();
1039 devfreq_resume();
1040 trace_suspend_resume(TPS("dpm_resume"), state.event, false);
1041}
1042
1043/**
1044 * device_complete - Complete a PM transition for given device.
1045 * @dev: Device to handle.
1046 * @state: PM transition of the system being carried out.
1047 */
1048static void device_complete(struct device *dev, pm_message_t state)
1049{
1050 void (*callback)(struct device *) = NULL;
1051 const char *info = NULL;
1052
1053 if (dev->power.syscore)
1054 return;
1055
1056 device_lock(dev);
1057
1058 if (dev->pm_domain) {
1059 info = "completing power domain ";
1060 callback = dev->pm_domain->ops.complete;
1061 } else if (dev->type && dev->type->pm) {
1062 info = "completing type ";
1063 callback = dev->type->pm->complete;
1064 } else if (dev->class && dev->class->pm) {
1065 info = "completing class ";
1066 callback = dev->class->pm->complete;
1067 } else if (dev->bus && dev->bus->pm) {
1068 info = "completing bus ";
1069 callback = dev->bus->pm->complete;
1070 }
1071
1072 if (!callback && dev->driver && dev->driver->pm) {
1073 info = "completing driver ";
1074 callback = dev->driver->pm->complete;
1075 }
1076
1077 if (callback) {
1078 pm_dev_dbg(dev, state, info);
1079 callback(dev);
1080 }
1081
1082 device_unlock(dev);
1083
1084 pm_runtime_put(dev);
1085}
1086
1087/**
1088 * dpm_complete - Complete a PM transition for all non-sysdev devices.
1089 * @state: PM transition of the system being carried out.
1090 *
1091 * Execute the ->complete() callbacks for all devices whose PM status is not
1092 * DPM_ON (this allows new devices to be registered).
1093 */
1094void dpm_complete(pm_message_t state)
1095{
1096 struct list_head list;
1097
1098 trace_suspend_resume(TPS("dpm_complete"), state.event, true);
1099 might_sleep();
1100
1101 INIT_LIST_HEAD(&list);
1102 mutex_lock(&dpm_list_mtx);
1103 while (!list_empty(&dpm_prepared_list)) {
1104 struct device *dev = to_device(dpm_prepared_list.prev);
1105
1106 get_device(dev);
1107 dev->power.is_prepared = false;
1108 list_move(&dev->power.entry, &list);
1109 mutex_unlock(&dpm_list_mtx);
1110
1111 trace_device_pm_callback_start(dev, "", state.event);
1112 device_complete(dev, state);
1113 trace_device_pm_callback_end(dev, 0);
1114
1115 mutex_lock(&dpm_list_mtx);
1116 put_device(dev);
1117 }
1118 list_splice(&list, &dpm_list);
1119 mutex_unlock(&dpm_list_mtx);
1120
1121 /* Allow device probing and trigger re-probing of deferred devices */
1122 device_unblock_probing();
1123 trace_suspend_resume(TPS("dpm_complete"), state.event, false);
1124}
1125
1126/**
1127 * dpm_resume_end - Execute "resume" callbacks and complete system transition.
1128 * @state: PM transition of the system being carried out.
1129 *
1130 * Execute "resume" callbacks for all devices and complete the PM transition of
1131 * the system.
1132 */
1133void dpm_resume_end(pm_message_t state)
1134{
1135 dpm_resume(state);
1136 dpm_complete(state);
1137}
1138EXPORT_SYMBOL_GPL(dpm_resume_end);
1139
1140
1141/*------------------------- Suspend routines -------------------------*/
1142
1143/**
1144 * resume_event - Return a "resume" message for given "suspend" sleep state.
1145 * @sleep_state: PM message representing a sleep state.
1146 *
1147 * Return a PM message representing the resume event corresponding to given
1148 * sleep state.
1149 */
1150static pm_message_t resume_event(pm_message_t sleep_state)
1151{
1152 switch (sleep_state.event) {
1153 case PM_EVENT_SUSPEND:
1154 return PMSG_RESUME;
1155 case PM_EVENT_FREEZE:
1156 case PM_EVENT_QUIESCE:
1157 return PMSG_RECOVER;
1158 case PM_EVENT_HIBERNATE:
1159 return PMSG_RESTORE;
1160 }
1161 return PMSG_ON;
1162}
1163
1164static void dpm_superior_set_must_resume(struct device *dev)
1165{
1166 struct device_link *link;
1167 int idx;
1168
1169 if (dev->parent)
1170 dev->parent->power.must_resume = true;
1171
1172 idx = device_links_read_lock();
1173
1174 list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
1175 link->supplier->power.must_resume = true;
1176
1177 device_links_read_unlock(idx);
1178}
1179
1180/**
1181 * __device_suspend_noirq - Execute a "noirq suspend" callback for given device.
1182 * @dev: Device to handle.
1183 * @state: PM transition of the system being carried out.
1184 * @async: If true, the device is being suspended asynchronously.
1185 *
1186 * The driver of @dev will not receive interrupts while this function is being
1187 * executed.
1188 */
1189static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
1190{
1191 pm_callback_t callback = NULL;
1192 const char *info = NULL;
1193 int error = 0;
1194
1195 TRACE_DEVICE(dev);
1196 TRACE_SUSPEND(0);
1197
1198 dpm_wait_for_subordinate(dev, async);
1199
1200 if (async_error)
1201 goto Complete;
1202
1203 if (dev->power.syscore || dev->power.direct_complete)
1204 goto Complete;
1205
1206 if (dev->pm_domain) {
1207 info = "noirq power domain ";
1208 callback = pm_noirq_op(&dev->pm_domain->ops, state);
1209 } else if (dev->type && dev->type->pm) {
1210 info = "noirq type ";
1211 callback = pm_noirq_op(dev->type->pm, state);
1212 } else if (dev->class && dev->class->pm) {
1213 info = "noirq class ";
1214 callback = pm_noirq_op(dev->class->pm, state);
1215 } else if (dev->bus && dev->bus->pm) {
1216 info = "noirq bus ";
1217 callback = pm_noirq_op(dev->bus->pm, state);
1218 }
1219 if (callback)
1220 goto Run;
1221
1222 if (dev_pm_skip_suspend(dev))
1223 goto Skip;
1224
1225 if (dev->driver && dev->driver->pm) {
1226 info = "noirq driver ";
1227 callback = pm_noirq_op(dev->driver->pm, state);
1228 }
1229
1230Run:
1231 error = dpm_run_callback(callback, dev, state, info);
1232 if (error) {
1233 async_error = error;
1234 goto Complete;
1235 }
1236
1237Skip:
1238 dev->power.is_noirq_suspended = true;
1239
1240 /*
1241 * Skipping the resume of devices that were in use right before the
1242 * system suspend (as indicated by their PM-runtime usage counters)
1243 * would be suboptimal. Also resume them if doing that is not allowed
1244 * to be skipped.
1245 */
1246 if (atomic_read(&dev->power.usage_count) > 1 ||
1247 !(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) &&
1248 dev->power.may_skip_resume))
1249 dev->power.must_resume = true;
1250
1251 if (dev->power.must_resume)
1252 dpm_superior_set_must_resume(dev);
1253
1254Complete:
1255 complete_all(&dev->power.completion);
1256 TRACE_SUSPEND(error);
1257 return error;
1258}
1259
1260static void async_suspend_noirq(void *data, async_cookie_t cookie)
1261{
1262 struct device *dev = (struct device *)data;
1263 int error;
1264
1265 error = __device_suspend_noirq(dev, pm_transition, true);
1266 if (error) {
1267 dpm_save_failed_dev(dev_name(dev));
1268 pm_dev_err(dev, pm_transition, " async", error);
1269 }
1270
1271 put_device(dev);
1272}
1273
1274static int device_suspend_noirq(struct device *dev)
1275{
1276 if (dpm_async_fn(dev, async_suspend_noirq))
1277 return 0;
1278
1279 return __device_suspend_noirq(dev, pm_transition, false);
1280}
1281
1282static int dpm_noirq_suspend_devices(pm_message_t state)
1283{
1284 ktime_t starttime = ktime_get();
1285 int error = 0;
1286
1287 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
1288 mutex_lock(&dpm_list_mtx);
1289 pm_transition = state;
1290 async_error = 0;
1291
1292 while (!list_empty(&dpm_late_early_list)) {
1293 struct device *dev = to_device(dpm_late_early_list.prev);
1294
1295 get_device(dev);
1296 mutex_unlock(&dpm_list_mtx);
1297
1298 error = device_suspend_noirq(dev);
1299
1300 mutex_lock(&dpm_list_mtx);
1301 if (error) {
1302 pm_dev_err(dev, state, " noirq", error);
1303 dpm_save_failed_dev(dev_name(dev));
1304 put_device(dev);
1305 break;
1306 }
1307 if (!list_empty(&dev->power.entry))
1308 list_move(&dev->power.entry, &dpm_noirq_list);
1309 put_device(dev);
1310
1311 if (async_error)
1312 break;
1313 }
1314 mutex_unlock(&dpm_list_mtx);
1315 async_synchronize_full();
1316 if (!error)
1317 error = async_error;
1318
1319 if (error) {
1320 suspend_stats.failed_suspend_noirq++;
1321 dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
1322 }
1323 dpm_show_time(starttime, state, error, "noirq");
1324 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
1325 return error;
1326}
1327
1328/**
1329 * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
1330 * @state: PM transition of the system being carried out.
1331 *
1332 * Prevent device drivers' interrupt handlers from being called and invoke
1333 * "noirq" suspend callbacks for all non-sysdev devices.
1334 */
1335int dpm_suspend_noirq(pm_message_t state)
1336{
1337 int ret;
1338
1339 cpuidle_pause();
1340
1341 device_wakeup_arm_wake_irqs();
1342 suspend_device_irqs();
1343
1344 ret = dpm_noirq_suspend_devices(state);
1345 if (ret)
1346 dpm_resume_noirq(resume_event(state));
1347
1348 return ret;
1349}
1350
1351static void dpm_propagate_wakeup_to_parent(struct device *dev)
1352{
1353 struct device *parent = dev->parent;
1354
1355 if (!parent)
1356 return;
1357
1358 spin_lock_irq(&parent->power.lock);
1359
1360 if (device_wakeup_path(dev) && !parent->power.ignore_children)
1361 parent->power.wakeup_path = true;
1362
1363 spin_unlock_irq(&parent->power.lock);
1364}
1365
1366/**
1367 * __device_suspend_late - Execute a "late suspend" callback for given device.
1368 * @dev: Device to handle.
1369 * @state: PM transition of the system being carried out.
1370 * @async: If true, the device is being suspended asynchronously.
1371 *
1372 * Runtime PM is disabled for @dev while this function is being executed.
1373 */
1374static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
1375{
1376 pm_callback_t callback = NULL;
1377 const char *info = NULL;
1378 int error = 0;
1379
1380 TRACE_DEVICE(dev);
1381 TRACE_SUSPEND(0);
1382
1383 __pm_runtime_disable(dev, false);
1384
1385 dpm_wait_for_subordinate(dev, async);
1386
1387 if (async_error)
1388 goto Complete;
1389
1390 if (pm_wakeup_pending()) {
1391 async_error = -EBUSY;
1392 goto Complete;
1393 }
1394
1395 if (dev->power.syscore || dev->power.direct_complete)
1396 goto Complete;
1397
1398 if (dev->pm_domain) {
1399 info = "late power domain ";
1400 callback = pm_late_early_op(&dev->pm_domain->ops, state);
1401 } else if (dev->type && dev->type->pm) {
1402 info = "late type ";
1403 callback = pm_late_early_op(dev->type->pm, state);
1404 } else if (dev->class && dev->class->pm) {
1405 info = "late class ";
1406 callback = pm_late_early_op(dev->class->pm, state);
1407 } else if (dev->bus && dev->bus->pm) {
1408 info = "late bus ";
1409 callback = pm_late_early_op(dev->bus->pm, state);
1410 }
1411 if (callback)
1412 goto Run;
1413
1414 if (dev_pm_skip_suspend(dev))
1415 goto Skip;
1416
1417 if (dev->driver && dev->driver->pm) {
1418 info = "late driver ";
1419 callback = pm_late_early_op(dev->driver->pm, state);
1420 }
1421
1422Run:
1423 error = dpm_run_callback(callback, dev, state, info);
1424 if (error) {
1425 async_error = error;
1426 goto Complete;
1427 }
1428 dpm_propagate_wakeup_to_parent(dev);
1429
1430Skip:
1431 dev->power.is_late_suspended = true;
1432
1433Complete:
1434 TRACE_SUSPEND(error);
1435 complete_all(&dev->power.completion);
1436 return error;
1437}
1438
1439static void async_suspend_late(void *data, async_cookie_t cookie)
1440{
1441 struct device *dev = (struct device *)data;
1442 int error;
1443
1444 error = __device_suspend_late(dev, pm_transition, true);
1445 if (error) {
1446 dpm_save_failed_dev(dev_name(dev));
1447 pm_dev_err(dev, pm_transition, " async", error);
1448 }
1449 put_device(dev);
1450}
1451
1452static int device_suspend_late(struct device *dev)
1453{
1454 if (dpm_async_fn(dev, async_suspend_late))
1455 return 0;
1456
1457 return __device_suspend_late(dev, pm_transition, false);
1458}
1459
1460/**
1461 * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
1462 * @state: PM transition of the system being carried out.
1463 */
1464int dpm_suspend_late(pm_message_t state)
1465{
1466 ktime_t starttime = ktime_get();
1467 int error = 0;
1468
1469 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
1470 mutex_lock(&dpm_list_mtx);
1471 pm_transition = state;
1472 async_error = 0;
1473
1474 while (!list_empty(&dpm_suspended_list)) {
1475 struct device *dev = to_device(dpm_suspended_list.prev);
1476
1477 get_device(dev);
1478 mutex_unlock(&dpm_list_mtx);
1479
1480 error = device_suspend_late(dev);
1481
1482 mutex_lock(&dpm_list_mtx);
1483 if (!list_empty(&dev->power.entry))
1484 list_move(&dev->power.entry, &dpm_late_early_list);
1485
1486 if (error) {
1487 pm_dev_err(dev, state, " late", error);
1488 dpm_save_failed_dev(dev_name(dev));
1489 put_device(dev);
1490 break;
1491 }
1492 put_device(dev);
1493
1494 if (async_error)
1495 break;
1496 }
1497 mutex_unlock(&dpm_list_mtx);
1498 async_synchronize_full();
1499 if (!error)
1500 error = async_error;
1501 if (error) {
1502 suspend_stats.failed_suspend_late++;
1503 dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
1504 dpm_resume_early(resume_event(state));
1505 }
1506 dpm_show_time(starttime, state, error, "late");
1507 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
1508 return error;
1509}
1510
1511/**
1512 * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
1513 * @state: PM transition of the system being carried out.
1514 */
1515int dpm_suspend_end(pm_message_t state)
1516{
1517 ktime_t starttime = ktime_get();
1518 int error;
1519
1520 error = dpm_suspend_late(state);
1521 if (error)
1522 goto out;
1523
1524 error = dpm_suspend_noirq(state);
1525 if (error)
1526 dpm_resume_early(resume_event(state));
1527
1528out:
1529 dpm_show_time(starttime, state, error, "end");
1530 return error;
1531}
1532EXPORT_SYMBOL_GPL(dpm_suspend_end);
1533
1534/**
1535 * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
1536 * @dev: Device to suspend.
1537 * @state: PM transition of the system being carried out.
1538 * @cb: Suspend callback to execute.
1539 * @info: string description of caller.
1540 */
1541static int legacy_suspend(struct device *dev, pm_message_t state,
1542 int (*cb)(struct device *dev, pm_message_t state),
1543 const char *info)
1544{
1545 int error;
1546 ktime_t calltime;
1547
1548 calltime = initcall_debug_start(dev, cb);
1549
1550 trace_device_pm_callback_start(dev, info, state.event);
1551 error = cb(dev, state);
1552 trace_device_pm_callback_end(dev, error);
1553 suspend_report_result(cb, error);
1554
1555 initcall_debug_report(dev, calltime, cb, error);
1556
1557 return error;
1558}
1559
1560static void dpm_clear_superiors_direct_complete(struct device *dev)
1561{
1562 struct device_link *link;
1563 int idx;
1564
1565 if (dev->parent) {
1566 spin_lock_irq(&dev->parent->power.lock);
1567 dev->parent->power.direct_complete = false;
1568 spin_unlock_irq(&dev->parent->power.lock);
1569 }
1570
1571 idx = device_links_read_lock();
1572
1573 list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) {
1574 spin_lock_irq(&link->supplier->power.lock);
1575 link->supplier->power.direct_complete = false;
1576 spin_unlock_irq(&link->supplier->power.lock);
1577 }
1578
1579 device_links_read_unlock(idx);
1580}
1581
1582/**
1583 * __device_suspend - Execute "suspend" callbacks for given device.
1584 * @dev: Device to handle.
1585 * @state: PM transition of the system being carried out.
1586 * @async: If true, the device is being suspended asynchronously.
1587 */
1588static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1589{
1590 pm_callback_t callback = NULL;
1591 const char *info = NULL;
1592 int error = 0;
1593 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
1594
1595 TRACE_DEVICE(dev);
1596 TRACE_SUSPEND(0);
1597
1598 dpm_wait_for_subordinate(dev, async);
1599
1600 if (async_error) {
1601 dev->power.direct_complete = false;
1602 goto Complete;
1603 }
1604
1605 /*
1606 * Wait for possible runtime PM transitions of the device in progress
1607 * to complete and if there's a runtime resume request pending for it,
1608 * resume it before proceeding with invoking the system-wide suspend
1609 * callbacks for it.
1610 *
1611 * If the system-wide suspend callbacks below change the configuration
1612 * of the device, they must disable runtime PM for it or otherwise
1613 * ensure that its runtime-resume callbacks will not be confused by that
1614 * change in case they are invoked going forward.
1615 */
1616 pm_runtime_barrier(dev);
1617
1618 if (pm_wakeup_pending()) {
1619 dev->power.direct_complete = false;
1620 async_error = -EBUSY;
1621 goto Complete;
1622 }
1623
1624 if (dev->power.syscore)
1625 goto Complete;
1626
1627 /* Avoid direct_complete to let wakeup_path propagate. */
1628 if (device_may_wakeup(dev) || device_wakeup_path(dev))
1629 dev->power.direct_complete = false;
1630
1631 if (dev->power.direct_complete) {
1632 if (pm_runtime_status_suspended(dev)) {
1633 pm_runtime_disable(dev);
1634 if (pm_runtime_status_suspended(dev)) {
1635 pm_dev_dbg(dev, state, "direct-complete ");
1636 goto Complete;
1637 }
1638
1639 pm_runtime_enable(dev);
1640 }
1641 dev->power.direct_complete = false;
1642 }
1643
1644 dev->power.may_skip_resume = true;
1645 dev->power.must_resume = !dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME);
1646
1647 dpm_watchdog_set(&wd, dev);
1648 device_lock(dev);
1649
1650 if (dev->pm_domain) {
1651 info = "power domain ";
1652 callback = pm_op(&dev->pm_domain->ops, state);
1653 goto Run;
1654 }
1655
1656 if (dev->type && dev->type->pm) {
1657 info = "type ";
1658 callback = pm_op(dev->type->pm, state);
1659 goto Run;
1660 }
1661
1662 if (dev->class && dev->class->pm) {
1663 info = "class ";
1664 callback = pm_op(dev->class->pm, state);
1665 goto Run;
1666 }
1667
1668 if (dev->bus) {
1669 if (dev->bus->pm) {
1670 info = "bus ";
1671 callback = pm_op(dev->bus->pm, state);
1672 } else if (dev->bus->suspend) {
1673 pm_dev_dbg(dev, state, "legacy bus ");
1674 error = legacy_suspend(dev, state, dev->bus->suspend,
1675 "legacy bus ");
1676 goto End;
1677 }
1678 }
1679
1680 Run:
1681 if (!callback && dev->driver && dev->driver->pm) {
1682 info = "driver ";
1683 callback = pm_op(dev->driver->pm, state);
1684 }
1685
1686 error = dpm_run_callback(callback, dev, state, info);
1687
1688 End:
1689 if (!error) {
1690 dev->power.is_suspended = true;
1691 if (device_may_wakeup(dev))
1692 dev->power.wakeup_path = true;
1693
1694 dpm_propagate_wakeup_to_parent(dev);
1695 dpm_clear_superiors_direct_complete(dev);
1696 }
1697
1698 device_unlock(dev);
1699 dpm_watchdog_clear(&wd);
1700
1701 Complete:
1702 if (error)
1703 async_error = error;
1704
1705 complete_all(&dev->power.completion);
1706 TRACE_SUSPEND(error);
1707 return error;
1708}
1709
1710static void async_suspend(void *data, async_cookie_t cookie)
1711{
1712 struct device *dev = (struct device *)data;
1713 int error;
1714
1715 error = __device_suspend(dev, pm_transition, true);
1716 if (error) {
1717 dpm_save_failed_dev(dev_name(dev));
1718 pm_dev_err(dev, pm_transition, " async", error);
1719 }
1720
1721 put_device(dev);
1722}
1723
1724static int device_suspend(struct device *dev)
1725{
1726 if (dpm_async_fn(dev, async_suspend))
1727 return 0;
1728
1729 return __device_suspend(dev, pm_transition, false);
1730}
1731
1732/**
1733 * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
1734 * @state: PM transition of the system being carried out.
1735 */
1736int dpm_suspend(pm_message_t state)
1737{
1738 ktime_t starttime = ktime_get();
1739 int error = 0;
1740
1741 trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
1742 might_sleep();
1743
1744 devfreq_suspend();
1745 cpufreq_suspend();
1746
1747 mutex_lock(&dpm_list_mtx);
1748 pm_transition = state;
1749 async_error = 0;
1750 while (!list_empty(&dpm_prepared_list)) {
1751 struct device *dev = to_device(dpm_prepared_list.prev);
1752
1753 get_device(dev);
1754 mutex_unlock(&dpm_list_mtx);
1755
1756 error = device_suspend(dev);
1757
1758 mutex_lock(&dpm_list_mtx);
1759 if (error) {
1760 pm_dev_err(dev, state, "", error);
1761 dpm_save_failed_dev(dev_name(dev));
1762 put_device(dev);
1763 break;
1764 }
1765 if (!list_empty(&dev->power.entry))
1766 list_move(&dev->power.entry, &dpm_suspended_list);
1767 put_device(dev);
1768 if (async_error)
1769 break;
1770 }
1771 mutex_unlock(&dpm_list_mtx);
1772 async_synchronize_full();
1773 if (!error)
1774 error = async_error;
1775 if (error) {
1776 suspend_stats.failed_suspend++;
1777 dpm_save_failed_step(SUSPEND_SUSPEND);
1778 }
1779 dpm_show_time(starttime, state, error, NULL);
1780 trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
1781 return error;
1782}
1783
1784/**
1785 * device_prepare - Prepare a device for system power transition.
1786 * @dev: Device to handle.
1787 * @state: PM transition of the system being carried out.
1788 *
1789 * Execute the ->prepare() callback(s) for given device. No new children of the
1790 * device may be registered after this function has returned.
1791 */
1792static int device_prepare(struct device *dev, pm_message_t state)
1793{
1794 int (*callback)(struct device *) = NULL;
1795 int ret = 0;
1796
1797 if (dev->power.syscore)
1798 return 0;
1799
1800 /*
1801 * If a device's parent goes into runtime suspend at the wrong time,
1802 * it won't be possible to resume the device. To prevent this we
1803 * block runtime suspend here, during the prepare phase, and allow
1804 * it again during the complete phase.
1805 */
1806 pm_runtime_get_noresume(dev);
1807
1808 device_lock(dev);
1809
1810 dev->power.wakeup_path = false;
1811
1812 if (dev->power.no_pm_callbacks)
1813 goto unlock;
1814
1815 if (dev->pm_domain)
1816 callback = dev->pm_domain->ops.prepare;
1817 else if (dev->type && dev->type->pm)
1818 callback = dev->type->pm->prepare;
1819 else if (dev->class && dev->class->pm)
1820 callback = dev->class->pm->prepare;
1821 else if (dev->bus && dev->bus->pm)
1822 callback = dev->bus->pm->prepare;
1823
1824 if (!callback && dev->driver && dev->driver->pm)
1825 callback = dev->driver->pm->prepare;
1826
1827 if (callback)
1828 ret = callback(dev);
1829
1830unlock:
1831 device_unlock(dev);
1832
1833 if (ret < 0) {
1834 suspend_report_result(callback, ret);
1835 pm_runtime_put(dev);
1836 return ret;
1837 }
1838 /*
1839 * A positive return value from ->prepare() means "this device appears
1840 * to be runtime-suspended and its state is fine, so if it really is
1841 * runtime-suspended, you can leave it in that state provided that you
1842 * will do the same thing with all of its descendants". This only
1843 * applies to suspend transitions, however.
1844 */
1845 spin_lock_irq(&dev->power.lock);
1846 dev->power.direct_complete = state.event == PM_EVENT_SUSPEND &&
1847 (ret > 0 || dev->power.no_pm_callbacks) &&
1848 !dev_pm_test_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE);
1849 spin_unlock_irq(&dev->power.lock);
1850 return 0;
1851}
1852
1853/**
1854 * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1855 * @state: PM transition of the system being carried out.
1856 *
1857 * Execute the ->prepare() callback(s) for all devices.
1858 */
1859int dpm_prepare(pm_message_t state)
1860{
1861 int error = 0;
1862
1863 trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
1864 might_sleep();
1865
1866 /*
1867 * Give a chance for the known devices to complete their probes, before
1868 * disable probing of devices. This sync point is important at least
1869 * at boot time + hibernation restore.
1870 */
1871 wait_for_device_probe();
1872 /*
1873 * It is unsafe if probing of devices will happen during suspend or
1874 * hibernation and system behavior will be unpredictable in this case.
1875 * So, let's prohibit device's probing here and defer their probes
1876 * instead. The normal behavior will be restored in dpm_complete().
1877 */
1878 device_block_probing();
1879
1880 mutex_lock(&dpm_list_mtx);
1881 while (!list_empty(&dpm_list)) {
1882 struct device *dev = to_device(dpm_list.next);
1883
1884 get_device(dev);
1885 mutex_unlock(&dpm_list_mtx);
1886
1887 trace_device_pm_callback_start(dev, "", state.event);
1888 error = device_prepare(dev, state);
1889 trace_device_pm_callback_end(dev, error);
1890
1891 mutex_lock(&dpm_list_mtx);
1892 if (error) {
1893 if (error == -EAGAIN) {
1894 put_device(dev);
1895 error = 0;
1896 continue;
1897 }
1898 dev_info(dev, "not prepared for power transition: code %d\n",
1899 error);
1900 put_device(dev);
1901 break;
1902 }
1903 dev->power.is_prepared = true;
1904 if (!list_empty(&dev->power.entry))
1905 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1906 put_device(dev);
1907 }
1908 mutex_unlock(&dpm_list_mtx);
1909 trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
1910 return error;
1911}
1912
1913/**
1914 * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1915 * @state: PM transition of the system being carried out.
1916 *
1917 * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1918 * callbacks for them.
1919 */
1920int dpm_suspend_start(pm_message_t state)
1921{
1922 ktime_t starttime = ktime_get();
1923 int error;
1924
1925 error = dpm_prepare(state);
1926 if (error) {
1927 suspend_stats.failed_prepare++;
1928 dpm_save_failed_step(SUSPEND_PREPARE);
1929 } else
1930 error = dpm_suspend(state);
1931 dpm_show_time(starttime, state, error, "start");
1932 return error;
1933}
1934EXPORT_SYMBOL_GPL(dpm_suspend_start);
1935
1936void __suspend_report_result(const char *function, void *fn, int ret)
1937{
1938 if (ret)
1939 pr_err("%s(): %pS returns %d\n", function, fn, ret);
1940}
1941EXPORT_SYMBOL_GPL(__suspend_report_result);
1942
1943/**
1944 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1945 * @subordinate: Device that needs to wait for @dev.
1946 * @dev: Device to wait for.
1947 */
1948int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
1949{
1950 dpm_wait(dev, subordinate->power.async_suspend);
1951 return async_error;
1952}
1953EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
1954
1955/**
1956 * dpm_for_each_dev - device iterator.
1957 * @data: data for the callback.
1958 * @fn: function to be called for each device.
1959 *
1960 * Iterate over devices in dpm_list, and call @fn for each device,
1961 * passing it @data.
1962 */
1963void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
1964{
1965 struct device *dev;
1966
1967 if (!fn)
1968 return;
1969
1970 device_pm_lock();
1971 list_for_each_entry(dev, &dpm_list, power.entry)
1972 fn(dev, data);
1973 device_pm_unlock();
1974}
1975EXPORT_SYMBOL_GPL(dpm_for_each_dev);
1976
1977static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
1978{
1979 if (!ops)
1980 return true;
1981
1982 return !ops->prepare &&
1983 !ops->suspend &&
1984 !ops->suspend_late &&
1985 !ops->suspend_noirq &&
1986 !ops->resume_noirq &&
1987 !ops->resume_early &&
1988 !ops->resume &&
1989 !ops->complete;
1990}
1991
1992void device_pm_check_callbacks(struct device *dev)
1993{
1994 spin_lock_irq(&dev->power.lock);
1995 dev->power.no_pm_callbacks =
1996 (!dev->bus || (pm_ops_is_empty(dev->bus->pm) &&
1997 !dev->bus->suspend && !dev->bus->resume)) &&
1998 (!dev->class || pm_ops_is_empty(dev->class->pm)) &&
1999 (!dev->type || pm_ops_is_empty(dev->type->pm)) &&
2000 (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
2001 (!dev->driver || (pm_ops_is_empty(dev->driver->pm) &&
2002 !dev->driver->suspend && !dev->driver->resume));
2003 spin_unlock_irq(&dev->power.lock);
2004}
2005
2006bool dev_pm_skip_suspend(struct device *dev)
2007{
2008 return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) &&
2009 pm_runtime_status_suspended(dev);
2010}
1/*
2 * drivers/base/power/main.c - Where the driver meets power management.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 * This file is released under the GPLv2
8 *
9 *
10 * The driver model core calls device_pm_add() when a device is registered.
11 * This will initialize the embedded device_pm_info object in the device
12 * and add it to the list of power-controlled devices. sysfs entries for
13 * controlling device power management will also be added.
14 *
15 * A separate list is used for keeping track of power info, because the power
16 * domain dependencies may differ from the ancestral dependencies that the
17 * subsystem list maintains.
18 */
19
20#include <linux/device.h>
21#include <linux/kallsyms.h>
22#include <linux/export.h>
23#include <linux/mutex.h>
24#include <linux/pm.h>
25#include <linux/pm_runtime.h>
26#include <linux/pm-trace.h>
27#include <linux/pm_wakeirq.h>
28#include <linux/interrupt.h>
29#include <linux/sched.h>
30#include <linux/async.h>
31#include <linux/suspend.h>
32#include <trace/events/power.h>
33#include <linux/cpufreq.h>
34#include <linux/cpuidle.h>
35#include <linux/timer.h>
36
37#include "../base.h"
38#include "power.h"
39
40typedef int (*pm_callback_t)(struct device *);
41
42/*
43 * The entries in the dpm_list list are in a depth first order, simply
44 * because children are guaranteed to be discovered after parents, and
45 * are inserted at the back of the list on discovery.
46 *
47 * Since device_pm_add() may be called with a device lock held,
48 * we must never try to acquire a device lock while holding
49 * dpm_list_mutex.
50 */
51
52LIST_HEAD(dpm_list);
53static LIST_HEAD(dpm_prepared_list);
54static LIST_HEAD(dpm_suspended_list);
55static LIST_HEAD(dpm_late_early_list);
56static LIST_HEAD(dpm_noirq_list);
57
58struct suspend_stats suspend_stats;
59static DEFINE_MUTEX(dpm_list_mtx);
60static pm_message_t pm_transition;
61
62static int async_error;
63
64static char *pm_verb(int event)
65{
66 switch (event) {
67 case PM_EVENT_SUSPEND:
68 return "suspend";
69 case PM_EVENT_RESUME:
70 return "resume";
71 case PM_EVENT_FREEZE:
72 return "freeze";
73 case PM_EVENT_QUIESCE:
74 return "quiesce";
75 case PM_EVENT_HIBERNATE:
76 return "hibernate";
77 case PM_EVENT_THAW:
78 return "thaw";
79 case PM_EVENT_RESTORE:
80 return "restore";
81 case PM_EVENT_RECOVER:
82 return "recover";
83 default:
84 return "(unknown PM event)";
85 }
86}
87
88/**
89 * device_pm_sleep_init - Initialize system suspend-related device fields.
90 * @dev: Device object being initialized.
91 */
92void device_pm_sleep_init(struct device *dev)
93{
94 dev->power.is_prepared = false;
95 dev->power.is_suspended = false;
96 dev->power.is_noirq_suspended = false;
97 dev->power.is_late_suspended = false;
98 init_completion(&dev->power.completion);
99 complete_all(&dev->power.completion);
100 dev->power.wakeup = NULL;
101 INIT_LIST_HEAD(&dev->power.entry);
102}
103
104/**
105 * device_pm_lock - Lock the list of active devices used by the PM core.
106 */
107void device_pm_lock(void)
108{
109 mutex_lock(&dpm_list_mtx);
110}
111
112/**
113 * device_pm_unlock - Unlock the list of active devices used by the PM core.
114 */
115void device_pm_unlock(void)
116{
117 mutex_unlock(&dpm_list_mtx);
118}
119
120/**
121 * device_pm_add - Add a device to the PM core's list of active devices.
122 * @dev: Device to add to the list.
123 */
124void device_pm_add(struct device *dev)
125{
126 pr_debug("PM: Adding info for %s:%s\n",
127 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
128 device_pm_check_callbacks(dev);
129 mutex_lock(&dpm_list_mtx);
130 if (dev->parent && dev->parent->power.is_prepared)
131 dev_warn(dev, "parent %s should not be sleeping\n",
132 dev_name(dev->parent));
133 list_add_tail(&dev->power.entry, &dpm_list);
134 mutex_unlock(&dpm_list_mtx);
135}
136
137/**
138 * device_pm_remove - Remove a device from the PM core's list of active devices.
139 * @dev: Device to be removed from the list.
140 */
141void device_pm_remove(struct device *dev)
142{
143 pr_debug("PM: Removing info for %s:%s\n",
144 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
145 complete_all(&dev->power.completion);
146 mutex_lock(&dpm_list_mtx);
147 list_del_init(&dev->power.entry);
148 mutex_unlock(&dpm_list_mtx);
149 device_wakeup_disable(dev);
150 pm_runtime_remove(dev);
151 device_pm_check_callbacks(dev);
152}
153
154/**
155 * device_pm_move_before - Move device in the PM core's list of active devices.
156 * @deva: Device to move in dpm_list.
157 * @devb: Device @deva should come before.
158 */
159void device_pm_move_before(struct device *deva, struct device *devb)
160{
161 pr_debug("PM: Moving %s:%s before %s:%s\n",
162 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
163 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
164 /* Delete deva from dpm_list and reinsert before devb. */
165 list_move_tail(&deva->power.entry, &devb->power.entry);
166}
167
168/**
169 * device_pm_move_after - Move device in the PM core's list of active devices.
170 * @deva: Device to move in dpm_list.
171 * @devb: Device @deva should come after.
172 */
173void device_pm_move_after(struct device *deva, struct device *devb)
174{
175 pr_debug("PM: Moving %s:%s after %s:%s\n",
176 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
177 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
178 /* Delete deva from dpm_list and reinsert after devb. */
179 list_move(&deva->power.entry, &devb->power.entry);
180}
181
182/**
183 * device_pm_move_last - Move device to end of the PM core's list of devices.
184 * @dev: Device to move in dpm_list.
185 */
186void device_pm_move_last(struct device *dev)
187{
188 pr_debug("PM: Moving %s:%s to end of list\n",
189 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
190 list_move_tail(&dev->power.entry, &dpm_list);
191}
192
193static ktime_t initcall_debug_start(struct device *dev)
194{
195 ktime_t calltime = ktime_set(0, 0);
196
197 if (pm_print_times_enabled) {
198 pr_info("calling %s+ @ %i, parent: %s\n",
199 dev_name(dev), task_pid_nr(current),
200 dev->parent ? dev_name(dev->parent) : "none");
201 calltime = ktime_get();
202 }
203
204 return calltime;
205}
206
207static void initcall_debug_report(struct device *dev, ktime_t calltime,
208 int error, pm_message_t state, char *info)
209{
210 ktime_t rettime;
211 s64 nsecs;
212
213 rettime = ktime_get();
214 nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime));
215
216 if (pm_print_times_enabled) {
217 pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
218 error, (unsigned long long)nsecs >> 10);
219 }
220}
221
222/**
223 * dpm_wait - Wait for a PM operation to complete.
224 * @dev: Device to wait for.
225 * @async: If unset, wait only if the device's power.async_suspend flag is set.
226 */
227static void dpm_wait(struct device *dev, bool async)
228{
229 if (!dev)
230 return;
231
232 if (async || (pm_async_enabled && dev->power.async_suspend))
233 wait_for_completion(&dev->power.completion);
234}
235
236static int dpm_wait_fn(struct device *dev, void *async_ptr)
237{
238 dpm_wait(dev, *((bool *)async_ptr));
239 return 0;
240}
241
242static void dpm_wait_for_children(struct device *dev, bool async)
243{
244 device_for_each_child(dev, &async, dpm_wait_fn);
245}
246
247/**
248 * pm_op - Return the PM operation appropriate for given PM event.
249 * @ops: PM operations to choose from.
250 * @state: PM transition of the system being carried out.
251 */
252static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
253{
254 switch (state.event) {
255#ifdef CONFIG_SUSPEND
256 case PM_EVENT_SUSPEND:
257 return ops->suspend;
258 case PM_EVENT_RESUME:
259 return ops->resume;
260#endif /* CONFIG_SUSPEND */
261#ifdef CONFIG_HIBERNATE_CALLBACKS
262 case PM_EVENT_FREEZE:
263 case PM_EVENT_QUIESCE:
264 return ops->freeze;
265 case PM_EVENT_HIBERNATE:
266 return ops->poweroff;
267 case PM_EVENT_THAW:
268 case PM_EVENT_RECOVER:
269 return ops->thaw;
270 break;
271 case PM_EVENT_RESTORE:
272 return ops->restore;
273#endif /* CONFIG_HIBERNATE_CALLBACKS */
274 }
275
276 return NULL;
277}
278
279/**
280 * pm_late_early_op - Return the PM operation appropriate for given PM event.
281 * @ops: PM operations to choose from.
282 * @state: PM transition of the system being carried out.
283 *
284 * Runtime PM is disabled for @dev while this function is being executed.
285 */
286static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
287 pm_message_t state)
288{
289 switch (state.event) {
290#ifdef CONFIG_SUSPEND
291 case PM_EVENT_SUSPEND:
292 return ops->suspend_late;
293 case PM_EVENT_RESUME:
294 return ops->resume_early;
295#endif /* CONFIG_SUSPEND */
296#ifdef CONFIG_HIBERNATE_CALLBACKS
297 case PM_EVENT_FREEZE:
298 case PM_EVENT_QUIESCE:
299 return ops->freeze_late;
300 case PM_EVENT_HIBERNATE:
301 return ops->poweroff_late;
302 case PM_EVENT_THAW:
303 case PM_EVENT_RECOVER:
304 return ops->thaw_early;
305 case PM_EVENT_RESTORE:
306 return ops->restore_early;
307#endif /* CONFIG_HIBERNATE_CALLBACKS */
308 }
309
310 return NULL;
311}
312
313/**
314 * pm_noirq_op - Return the PM operation appropriate for given PM event.
315 * @ops: PM operations to choose from.
316 * @state: PM transition of the system being carried out.
317 *
318 * The driver of @dev will not receive interrupts while this function is being
319 * executed.
320 */
321static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
322{
323 switch (state.event) {
324#ifdef CONFIG_SUSPEND
325 case PM_EVENT_SUSPEND:
326 return ops->suspend_noirq;
327 case PM_EVENT_RESUME:
328 return ops->resume_noirq;
329#endif /* CONFIG_SUSPEND */
330#ifdef CONFIG_HIBERNATE_CALLBACKS
331 case PM_EVENT_FREEZE:
332 case PM_EVENT_QUIESCE:
333 return ops->freeze_noirq;
334 case PM_EVENT_HIBERNATE:
335 return ops->poweroff_noirq;
336 case PM_EVENT_THAW:
337 case PM_EVENT_RECOVER:
338 return ops->thaw_noirq;
339 case PM_EVENT_RESTORE:
340 return ops->restore_noirq;
341#endif /* CONFIG_HIBERNATE_CALLBACKS */
342 }
343
344 return NULL;
345}
346
347static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
348{
349 dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
350 ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
351 ", may wakeup" : "");
352}
353
354static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
355 int error)
356{
357 printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
358 dev_name(dev), pm_verb(state.event), info, error);
359}
360
361static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info)
362{
363 ktime_t calltime;
364 u64 usecs64;
365 int usecs;
366
367 calltime = ktime_get();
368 usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
369 do_div(usecs64, NSEC_PER_USEC);
370 usecs = usecs64;
371 if (usecs == 0)
372 usecs = 1;
373 pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n",
374 info ?: "", info ? " " : "", pm_verb(state.event),
375 usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
376}
377
378static int dpm_run_callback(pm_callback_t cb, struct device *dev,
379 pm_message_t state, char *info)
380{
381 ktime_t calltime;
382 int error;
383
384 if (!cb)
385 return 0;
386
387 calltime = initcall_debug_start(dev);
388
389 pm_dev_dbg(dev, state, info);
390 trace_device_pm_callback_start(dev, info, state.event);
391 error = cb(dev);
392 trace_device_pm_callback_end(dev, error);
393 suspend_report_result(cb, error);
394
395 initcall_debug_report(dev, calltime, error, state, info);
396
397 return error;
398}
399
400#ifdef CONFIG_DPM_WATCHDOG
401struct dpm_watchdog {
402 struct device *dev;
403 struct task_struct *tsk;
404 struct timer_list timer;
405};
406
407#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
408 struct dpm_watchdog wd
409
410/**
411 * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
412 * @data: Watchdog object address.
413 *
414 * Called when a driver has timed out suspending or resuming.
415 * There's not much we can do here to recover so panic() to
416 * capture a crash-dump in pstore.
417 */
418static void dpm_watchdog_handler(unsigned long data)
419{
420 struct dpm_watchdog *wd = (void *)data;
421
422 dev_emerg(wd->dev, "**** DPM device timeout ****\n");
423 show_stack(wd->tsk, NULL);
424 panic("%s %s: unrecoverable failure\n",
425 dev_driver_string(wd->dev), dev_name(wd->dev));
426}
427
428/**
429 * dpm_watchdog_set - Enable pm watchdog for given device.
430 * @wd: Watchdog. Must be allocated on the stack.
431 * @dev: Device to handle.
432 */
433static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
434{
435 struct timer_list *timer = &wd->timer;
436
437 wd->dev = dev;
438 wd->tsk = current;
439
440 init_timer_on_stack(timer);
441 /* use same timeout value for both suspend and resume */
442 timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
443 timer->function = dpm_watchdog_handler;
444 timer->data = (unsigned long)wd;
445 add_timer(timer);
446}
447
448/**
449 * dpm_watchdog_clear - Disable suspend/resume watchdog.
450 * @wd: Watchdog to disable.
451 */
452static void dpm_watchdog_clear(struct dpm_watchdog *wd)
453{
454 struct timer_list *timer = &wd->timer;
455
456 del_timer_sync(timer);
457 destroy_timer_on_stack(timer);
458}
459#else
460#define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
461#define dpm_watchdog_set(x, y)
462#define dpm_watchdog_clear(x)
463#endif
464
465/*------------------------- Resume routines -------------------------*/
466
467/**
468 * device_resume_noirq - Execute an "early resume" callback for given device.
469 * @dev: Device to handle.
470 * @state: PM transition of the system being carried out.
471 * @async: If true, the device is being resumed asynchronously.
472 *
473 * The driver of @dev will not receive interrupts while this function is being
474 * executed.
475 */
476static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
477{
478 pm_callback_t callback = NULL;
479 char *info = NULL;
480 int error = 0;
481
482 TRACE_DEVICE(dev);
483 TRACE_RESUME(0);
484
485 if (dev->power.syscore || dev->power.direct_complete)
486 goto Out;
487
488 if (!dev->power.is_noirq_suspended)
489 goto Out;
490
491 dpm_wait(dev->parent, async);
492
493 if (dev->pm_domain) {
494 info = "noirq power domain ";
495 callback = pm_noirq_op(&dev->pm_domain->ops, state);
496 } else if (dev->type && dev->type->pm) {
497 info = "noirq type ";
498 callback = pm_noirq_op(dev->type->pm, state);
499 } else if (dev->class && dev->class->pm) {
500 info = "noirq class ";
501 callback = pm_noirq_op(dev->class->pm, state);
502 } else if (dev->bus && dev->bus->pm) {
503 info = "noirq bus ";
504 callback = pm_noirq_op(dev->bus->pm, state);
505 }
506
507 if (!callback && dev->driver && dev->driver->pm) {
508 info = "noirq driver ";
509 callback = pm_noirq_op(dev->driver->pm, state);
510 }
511
512 error = dpm_run_callback(callback, dev, state, info);
513 dev->power.is_noirq_suspended = false;
514
515 Out:
516 complete_all(&dev->power.completion);
517 TRACE_RESUME(error);
518 return error;
519}
520
521static bool is_async(struct device *dev)
522{
523 return dev->power.async_suspend && pm_async_enabled
524 && !pm_trace_is_enabled();
525}
526
527static void async_resume_noirq(void *data, async_cookie_t cookie)
528{
529 struct device *dev = (struct device *)data;
530 int error;
531
532 error = device_resume_noirq(dev, pm_transition, true);
533 if (error)
534 pm_dev_err(dev, pm_transition, " async", error);
535
536 put_device(dev);
537}
538
539/**
540 * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
541 * @state: PM transition of the system being carried out.
542 *
543 * Call the "noirq" resume handlers for all devices in dpm_noirq_list and
544 * enable device drivers to receive interrupts.
545 */
546void dpm_resume_noirq(pm_message_t state)
547{
548 struct device *dev;
549 ktime_t starttime = ktime_get();
550
551 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
552 mutex_lock(&dpm_list_mtx);
553 pm_transition = state;
554
555 /*
556 * Advanced the async threads upfront,
557 * in case the starting of async threads is
558 * delayed by non-async resuming devices.
559 */
560 list_for_each_entry(dev, &dpm_noirq_list, power.entry) {
561 reinit_completion(&dev->power.completion);
562 if (is_async(dev)) {
563 get_device(dev);
564 async_schedule(async_resume_noirq, dev);
565 }
566 }
567
568 while (!list_empty(&dpm_noirq_list)) {
569 dev = to_device(dpm_noirq_list.next);
570 get_device(dev);
571 list_move_tail(&dev->power.entry, &dpm_late_early_list);
572 mutex_unlock(&dpm_list_mtx);
573
574 if (!is_async(dev)) {
575 int error;
576
577 error = device_resume_noirq(dev, state, false);
578 if (error) {
579 suspend_stats.failed_resume_noirq++;
580 dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
581 dpm_save_failed_dev(dev_name(dev));
582 pm_dev_err(dev, state, " noirq", error);
583 }
584 }
585
586 mutex_lock(&dpm_list_mtx);
587 put_device(dev);
588 }
589 mutex_unlock(&dpm_list_mtx);
590 async_synchronize_full();
591 dpm_show_time(starttime, state, "noirq");
592 resume_device_irqs();
593 device_wakeup_disarm_wake_irqs();
594 cpuidle_resume();
595 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
596}
597
598/**
599 * device_resume_early - Execute an "early resume" callback for given device.
600 * @dev: Device to handle.
601 * @state: PM transition of the system being carried out.
602 * @async: If true, the device is being resumed asynchronously.
603 *
604 * Runtime PM is disabled for @dev while this function is being executed.
605 */
606static int device_resume_early(struct device *dev, pm_message_t state, bool async)
607{
608 pm_callback_t callback = NULL;
609 char *info = NULL;
610 int error = 0;
611
612 TRACE_DEVICE(dev);
613 TRACE_RESUME(0);
614
615 if (dev->power.syscore || dev->power.direct_complete)
616 goto Out;
617
618 if (!dev->power.is_late_suspended)
619 goto Out;
620
621 dpm_wait(dev->parent, async);
622
623 if (dev->pm_domain) {
624 info = "early power domain ";
625 callback = pm_late_early_op(&dev->pm_domain->ops, state);
626 } else if (dev->type && dev->type->pm) {
627 info = "early type ";
628 callback = pm_late_early_op(dev->type->pm, state);
629 } else if (dev->class && dev->class->pm) {
630 info = "early class ";
631 callback = pm_late_early_op(dev->class->pm, state);
632 } else if (dev->bus && dev->bus->pm) {
633 info = "early bus ";
634 callback = pm_late_early_op(dev->bus->pm, state);
635 }
636
637 if (!callback && dev->driver && dev->driver->pm) {
638 info = "early driver ";
639 callback = pm_late_early_op(dev->driver->pm, state);
640 }
641
642 error = dpm_run_callback(callback, dev, state, info);
643 dev->power.is_late_suspended = false;
644
645 Out:
646 TRACE_RESUME(error);
647
648 pm_runtime_enable(dev);
649 complete_all(&dev->power.completion);
650 return error;
651}
652
653static void async_resume_early(void *data, async_cookie_t cookie)
654{
655 struct device *dev = (struct device *)data;
656 int error;
657
658 error = device_resume_early(dev, pm_transition, true);
659 if (error)
660 pm_dev_err(dev, pm_transition, " async", error);
661
662 put_device(dev);
663}
664
665/**
666 * dpm_resume_early - Execute "early resume" callbacks for all devices.
667 * @state: PM transition of the system being carried out.
668 */
669void dpm_resume_early(pm_message_t state)
670{
671 struct device *dev;
672 ktime_t starttime = ktime_get();
673
674 trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
675 mutex_lock(&dpm_list_mtx);
676 pm_transition = state;
677
678 /*
679 * Advanced the async threads upfront,
680 * in case the starting of async threads is
681 * delayed by non-async resuming devices.
682 */
683 list_for_each_entry(dev, &dpm_late_early_list, power.entry) {
684 reinit_completion(&dev->power.completion);
685 if (is_async(dev)) {
686 get_device(dev);
687 async_schedule(async_resume_early, dev);
688 }
689 }
690
691 while (!list_empty(&dpm_late_early_list)) {
692 dev = to_device(dpm_late_early_list.next);
693 get_device(dev);
694 list_move_tail(&dev->power.entry, &dpm_suspended_list);
695 mutex_unlock(&dpm_list_mtx);
696
697 if (!is_async(dev)) {
698 int error;
699
700 error = device_resume_early(dev, state, false);
701 if (error) {
702 suspend_stats.failed_resume_early++;
703 dpm_save_failed_step(SUSPEND_RESUME_EARLY);
704 dpm_save_failed_dev(dev_name(dev));
705 pm_dev_err(dev, state, " early", error);
706 }
707 }
708 mutex_lock(&dpm_list_mtx);
709 put_device(dev);
710 }
711 mutex_unlock(&dpm_list_mtx);
712 async_synchronize_full();
713 dpm_show_time(starttime, state, "early");
714 trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
715}
716
717/**
718 * dpm_resume_start - Execute "noirq" and "early" device callbacks.
719 * @state: PM transition of the system being carried out.
720 */
721void dpm_resume_start(pm_message_t state)
722{
723 dpm_resume_noirq(state);
724 dpm_resume_early(state);
725}
726EXPORT_SYMBOL_GPL(dpm_resume_start);
727
728/**
729 * device_resume - Execute "resume" callbacks for given device.
730 * @dev: Device to handle.
731 * @state: PM transition of the system being carried out.
732 * @async: If true, the device is being resumed asynchronously.
733 */
734static int device_resume(struct device *dev, pm_message_t state, bool async)
735{
736 pm_callback_t callback = NULL;
737 char *info = NULL;
738 int error = 0;
739 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
740
741 TRACE_DEVICE(dev);
742 TRACE_RESUME(0);
743
744 if (dev->power.syscore)
745 goto Complete;
746
747 if (dev->power.direct_complete) {
748 /* Match the pm_runtime_disable() in __device_suspend(). */
749 pm_runtime_enable(dev);
750 goto Complete;
751 }
752
753 dpm_wait(dev->parent, async);
754 dpm_watchdog_set(&wd, dev);
755 device_lock(dev);
756
757 /*
758 * This is a fib. But we'll allow new children to be added below
759 * a resumed device, even if the device hasn't been completed yet.
760 */
761 dev->power.is_prepared = false;
762
763 if (!dev->power.is_suspended)
764 goto Unlock;
765
766 if (dev->pm_domain) {
767 info = "power domain ";
768 callback = pm_op(&dev->pm_domain->ops, state);
769 goto Driver;
770 }
771
772 if (dev->type && dev->type->pm) {
773 info = "type ";
774 callback = pm_op(dev->type->pm, state);
775 goto Driver;
776 }
777
778 if (dev->class) {
779 if (dev->class->pm) {
780 info = "class ";
781 callback = pm_op(dev->class->pm, state);
782 goto Driver;
783 } else if (dev->class->resume) {
784 info = "legacy class ";
785 callback = dev->class->resume;
786 goto End;
787 }
788 }
789
790 if (dev->bus) {
791 if (dev->bus->pm) {
792 info = "bus ";
793 callback = pm_op(dev->bus->pm, state);
794 } else if (dev->bus->resume) {
795 info = "legacy bus ";
796 callback = dev->bus->resume;
797 goto End;
798 }
799 }
800
801 Driver:
802 if (!callback && dev->driver && dev->driver->pm) {
803 info = "driver ";
804 callback = pm_op(dev->driver->pm, state);
805 }
806
807 End:
808 error = dpm_run_callback(callback, dev, state, info);
809 dev->power.is_suspended = false;
810
811 Unlock:
812 device_unlock(dev);
813 dpm_watchdog_clear(&wd);
814
815 Complete:
816 complete_all(&dev->power.completion);
817
818 TRACE_RESUME(error);
819
820 return error;
821}
822
823static void async_resume(void *data, async_cookie_t cookie)
824{
825 struct device *dev = (struct device *)data;
826 int error;
827
828 error = device_resume(dev, pm_transition, true);
829 if (error)
830 pm_dev_err(dev, pm_transition, " async", error);
831 put_device(dev);
832}
833
834/**
835 * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
836 * @state: PM transition of the system being carried out.
837 *
838 * Execute the appropriate "resume" callback for all devices whose status
839 * indicates that they are suspended.
840 */
841void dpm_resume(pm_message_t state)
842{
843 struct device *dev;
844 ktime_t starttime = ktime_get();
845
846 trace_suspend_resume(TPS("dpm_resume"), state.event, true);
847 might_sleep();
848
849 mutex_lock(&dpm_list_mtx);
850 pm_transition = state;
851 async_error = 0;
852
853 list_for_each_entry(dev, &dpm_suspended_list, power.entry) {
854 reinit_completion(&dev->power.completion);
855 if (is_async(dev)) {
856 get_device(dev);
857 async_schedule(async_resume, dev);
858 }
859 }
860
861 while (!list_empty(&dpm_suspended_list)) {
862 dev = to_device(dpm_suspended_list.next);
863 get_device(dev);
864 if (!is_async(dev)) {
865 int error;
866
867 mutex_unlock(&dpm_list_mtx);
868
869 error = device_resume(dev, state, false);
870 if (error) {
871 suspend_stats.failed_resume++;
872 dpm_save_failed_step(SUSPEND_RESUME);
873 dpm_save_failed_dev(dev_name(dev));
874 pm_dev_err(dev, state, "", error);
875 }
876
877 mutex_lock(&dpm_list_mtx);
878 }
879 if (!list_empty(&dev->power.entry))
880 list_move_tail(&dev->power.entry, &dpm_prepared_list);
881 put_device(dev);
882 }
883 mutex_unlock(&dpm_list_mtx);
884 async_synchronize_full();
885 dpm_show_time(starttime, state, NULL);
886
887 cpufreq_resume();
888 trace_suspend_resume(TPS("dpm_resume"), state.event, false);
889}
890
891/**
892 * device_complete - Complete a PM transition for given device.
893 * @dev: Device to handle.
894 * @state: PM transition of the system being carried out.
895 */
896static void device_complete(struct device *dev, pm_message_t state)
897{
898 void (*callback)(struct device *) = NULL;
899 char *info = NULL;
900
901 if (dev->power.syscore)
902 return;
903
904 device_lock(dev);
905
906 if (dev->pm_domain) {
907 info = "completing power domain ";
908 callback = dev->pm_domain->ops.complete;
909 } else if (dev->type && dev->type->pm) {
910 info = "completing type ";
911 callback = dev->type->pm->complete;
912 } else if (dev->class && dev->class->pm) {
913 info = "completing class ";
914 callback = dev->class->pm->complete;
915 } else if (dev->bus && dev->bus->pm) {
916 info = "completing bus ";
917 callback = dev->bus->pm->complete;
918 }
919
920 if (!callback && dev->driver && dev->driver->pm) {
921 info = "completing driver ";
922 callback = dev->driver->pm->complete;
923 }
924
925 if (callback) {
926 pm_dev_dbg(dev, state, info);
927 callback(dev);
928 }
929
930 device_unlock(dev);
931
932 pm_runtime_put(dev);
933}
934
935/**
936 * dpm_complete - Complete a PM transition for all non-sysdev devices.
937 * @state: PM transition of the system being carried out.
938 *
939 * Execute the ->complete() callbacks for all devices whose PM status is not
940 * DPM_ON (this allows new devices to be registered).
941 */
942void dpm_complete(pm_message_t state)
943{
944 struct list_head list;
945
946 trace_suspend_resume(TPS("dpm_complete"), state.event, true);
947 might_sleep();
948
949 INIT_LIST_HEAD(&list);
950 mutex_lock(&dpm_list_mtx);
951 while (!list_empty(&dpm_prepared_list)) {
952 struct device *dev = to_device(dpm_prepared_list.prev);
953
954 get_device(dev);
955 dev->power.is_prepared = false;
956 list_move(&dev->power.entry, &list);
957 mutex_unlock(&dpm_list_mtx);
958
959 trace_device_pm_callback_start(dev, "", state.event);
960 device_complete(dev, state);
961 trace_device_pm_callback_end(dev, 0);
962
963 mutex_lock(&dpm_list_mtx);
964 put_device(dev);
965 }
966 list_splice(&list, &dpm_list);
967 mutex_unlock(&dpm_list_mtx);
968
969 /* Allow device probing and trigger re-probing of deferred devices */
970 device_unblock_probing();
971 trace_suspend_resume(TPS("dpm_complete"), state.event, false);
972}
973
974/**
975 * dpm_resume_end - Execute "resume" callbacks and complete system transition.
976 * @state: PM transition of the system being carried out.
977 *
978 * Execute "resume" callbacks for all devices and complete the PM transition of
979 * the system.
980 */
981void dpm_resume_end(pm_message_t state)
982{
983 dpm_resume(state);
984 dpm_complete(state);
985}
986EXPORT_SYMBOL_GPL(dpm_resume_end);
987
988
989/*------------------------- Suspend routines -------------------------*/
990
991/**
992 * resume_event - Return a "resume" message for given "suspend" sleep state.
993 * @sleep_state: PM message representing a sleep state.
994 *
995 * Return a PM message representing the resume event corresponding to given
996 * sleep state.
997 */
998static pm_message_t resume_event(pm_message_t sleep_state)
999{
1000 switch (sleep_state.event) {
1001 case PM_EVENT_SUSPEND:
1002 return PMSG_RESUME;
1003 case PM_EVENT_FREEZE:
1004 case PM_EVENT_QUIESCE:
1005 return PMSG_RECOVER;
1006 case PM_EVENT_HIBERNATE:
1007 return PMSG_RESTORE;
1008 }
1009 return PMSG_ON;
1010}
1011
1012/**
1013 * device_suspend_noirq - Execute a "late suspend" callback for given device.
1014 * @dev: Device to handle.
1015 * @state: PM transition of the system being carried out.
1016 * @async: If true, the device is being suspended asynchronously.
1017 *
1018 * The driver of @dev will not receive interrupts while this function is being
1019 * executed.
1020 */
1021static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
1022{
1023 pm_callback_t callback = NULL;
1024 char *info = NULL;
1025 int error = 0;
1026
1027 TRACE_DEVICE(dev);
1028 TRACE_SUSPEND(0);
1029
1030 if (async_error)
1031 goto Complete;
1032
1033 if (pm_wakeup_pending()) {
1034 async_error = -EBUSY;
1035 goto Complete;
1036 }
1037
1038 if (dev->power.syscore || dev->power.direct_complete)
1039 goto Complete;
1040
1041 dpm_wait_for_children(dev, async);
1042
1043 if (dev->pm_domain) {
1044 info = "noirq power domain ";
1045 callback = pm_noirq_op(&dev->pm_domain->ops, state);
1046 } else if (dev->type && dev->type->pm) {
1047 info = "noirq type ";
1048 callback = pm_noirq_op(dev->type->pm, state);
1049 } else if (dev->class && dev->class->pm) {
1050 info = "noirq class ";
1051 callback = pm_noirq_op(dev->class->pm, state);
1052 } else if (dev->bus && dev->bus->pm) {
1053 info = "noirq bus ";
1054 callback = pm_noirq_op(dev->bus->pm, state);
1055 }
1056
1057 if (!callback && dev->driver && dev->driver->pm) {
1058 info = "noirq driver ";
1059 callback = pm_noirq_op(dev->driver->pm, state);
1060 }
1061
1062 error = dpm_run_callback(callback, dev, state, info);
1063 if (!error)
1064 dev->power.is_noirq_suspended = true;
1065 else
1066 async_error = error;
1067
1068Complete:
1069 complete_all(&dev->power.completion);
1070 TRACE_SUSPEND(error);
1071 return error;
1072}
1073
1074static void async_suspend_noirq(void *data, async_cookie_t cookie)
1075{
1076 struct device *dev = (struct device *)data;
1077 int error;
1078
1079 error = __device_suspend_noirq(dev, pm_transition, true);
1080 if (error) {
1081 dpm_save_failed_dev(dev_name(dev));
1082 pm_dev_err(dev, pm_transition, " async", error);
1083 }
1084
1085 put_device(dev);
1086}
1087
1088static int device_suspend_noirq(struct device *dev)
1089{
1090 reinit_completion(&dev->power.completion);
1091
1092 if (is_async(dev)) {
1093 get_device(dev);
1094 async_schedule(async_suspend_noirq, dev);
1095 return 0;
1096 }
1097 return __device_suspend_noirq(dev, pm_transition, false);
1098}
1099
1100/**
1101 * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
1102 * @state: PM transition of the system being carried out.
1103 *
1104 * Prevent device drivers from receiving interrupts and call the "noirq" suspend
1105 * handlers for all non-sysdev devices.
1106 */
1107int dpm_suspend_noirq(pm_message_t state)
1108{
1109 ktime_t starttime = ktime_get();
1110 int error = 0;
1111
1112 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
1113 cpuidle_pause();
1114 device_wakeup_arm_wake_irqs();
1115 suspend_device_irqs();
1116 mutex_lock(&dpm_list_mtx);
1117 pm_transition = state;
1118 async_error = 0;
1119
1120 while (!list_empty(&dpm_late_early_list)) {
1121 struct device *dev = to_device(dpm_late_early_list.prev);
1122
1123 get_device(dev);
1124 mutex_unlock(&dpm_list_mtx);
1125
1126 error = device_suspend_noirq(dev);
1127
1128 mutex_lock(&dpm_list_mtx);
1129 if (error) {
1130 pm_dev_err(dev, state, " noirq", error);
1131 dpm_save_failed_dev(dev_name(dev));
1132 put_device(dev);
1133 break;
1134 }
1135 if (!list_empty(&dev->power.entry))
1136 list_move(&dev->power.entry, &dpm_noirq_list);
1137 put_device(dev);
1138
1139 if (async_error)
1140 break;
1141 }
1142 mutex_unlock(&dpm_list_mtx);
1143 async_synchronize_full();
1144 if (!error)
1145 error = async_error;
1146
1147 if (error) {
1148 suspend_stats.failed_suspend_noirq++;
1149 dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
1150 dpm_resume_noirq(resume_event(state));
1151 } else {
1152 dpm_show_time(starttime, state, "noirq");
1153 }
1154 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
1155 return error;
1156}
1157
1158/**
1159 * device_suspend_late - Execute a "late suspend" callback for given device.
1160 * @dev: Device to handle.
1161 * @state: PM transition of the system being carried out.
1162 * @async: If true, the device is being suspended asynchronously.
1163 *
1164 * Runtime PM is disabled for @dev while this function is being executed.
1165 */
1166static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
1167{
1168 pm_callback_t callback = NULL;
1169 char *info = NULL;
1170 int error = 0;
1171
1172 TRACE_DEVICE(dev);
1173 TRACE_SUSPEND(0);
1174
1175 __pm_runtime_disable(dev, false);
1176
1177 if (async_error)
1178 goto Complete;
1179
1180 if (pm_wakeup_pending()) {
1181 async_error = -EBUSY;
1182 goto Complete;
1183 }
1184
1185 if (dev->power.syscore || dev->power.direct_complete)
1186 goto Complete;
1187
1188 dpm_wait_for_children(dev, async);
1189
1190 if (dev->pm_domain) {
1191 info = "late power domain ";
1192 callback = pm_late_early_op(&dev->pm_domain->ops, state);
1193 } else if (dev->type && dev->type->pm) {
1194 info = "late type ";
1195 callback = pm_late_early_op(dev->type->pm, state);
1196 } else if (dev->class && dev->class->pm) {
1197 info = "late class ";
1198 callback = pm_late_early_op(dev->class->pm, state);
1199 } else if (dev->bus && dev->bus->pm) {
1200 info = "late bus ";
1201 callback = pm_late_early_op(dev->bus->pm, state);
1202 }
1203
1204 if (!callback && dev->driver && dev->driver->pm) {
1205 info = "late driver ";
1206 callback = pm_late_early_op(dev->driver->pm, state);
1207 }
1208
1209 error = dpm_run_callback(callback, dev, state, info);
1210 if (!error)
1211 dev->power.is_late_suspended = true;
1212 else
1213 async_error = error;
1214
1215Complete:
1216 TRACE_SUSPEND(error);
1217 complete_all(&dev->power.completion);
1218 return error;
1219}
1220
1221static void async_suspend_late(void *data, async_cookie_t cookie)
1222{
1223 struct device *dev = (struct device *)data;
1224 int error;
1225
1226 error = __device_suspend_late(dev, pm_transition, true);
1227 if (error) {
1228 dpm_save_failed_dev(dev_name(dev));
1229 pm_dev_err(dev, pm_transition, " async", error);
1230 }
1231 put_device(dev);
1232}
1233
1234static int device_suspend_late(struct device *dev)
1235{
1236 reinit_completion(&dev->power.completion);
1237
1238 if (is_async(dev)) {
1239 get_device(dev);
1240 async_schedule(async_suspend_late, dev);
1241 return 0;
1242 }
1243
1244 return __device_suspend_late(dev, pm_transition, false);
1245}
1246
1247/**
1248 * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
1249 * @state: PM transition of the system being carried out.
1250 */
1251int dpm_suspend_late(pm_message_t state)
1252{
1253 ktime_t starttime = ktime_get();
1254 int error = 0;
1255
1256 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
1257 mutex_lock(&dpm_list_mtx);
1258 pm_transition = state;
1259 async_error = 0;
1260
1261 while (!list_empty(&dpm_suspended_list)) {
1262 struct device *dev = to_device(dpm_suspended_list.prev);
1263
1264 get_device(dev);
1265 mutex_unlock(&dpm_list_mtx);
1266
1267 error = device_suspend_late(dev);
1268
1269 mutex_lock(&dpm_list_mtx);
1270 if (error) {
1271 pm_dev_err(dev, state, " late", error);
1272 dpm_save_failed_dev(dev_name(dev));
1273 put_device(dev);
1274 break;
1275 }
1276 if (!list_empty(&dev->power.entry))
1277 list_move(&dev->power.entry, &dpm_late_early_list);
1278 put_device(dev);
1279
1280 if (async_error)
1281 break;
1282 }
1283 mutex_unlock(&dpm_list_mtx);
1284 async_synchronize_full();
1285 if (!error)
1286 error = async_error;
1287 if (error) {
1288 suspend_stats.failed_suspend_late++;
1289 dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
1290 dpm_resume_early(resume_event(state));
1291 } else {
1292 dpm_show_time(starttime, state, "late");
1293 }
1294 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
1295 return error;
1296}
1297
1298/**
1299 * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
1300 * @state: PM transition of the system being carried out.
1301 */
1302int dpm_suspend_end(pm_message_t state)
1303{
1304 int error = dpm_suspend_late(state);
1305 if (error)
1306 return error;
1307
1308 error = dpm_suspend_noirq(state);
1309 if (error) {
1310 dpm_resume_early(resume_event(state));
1311 return error;
1312 }
1313
1314 return 0;
1315}
1316EXPORT_SYMBOL_GPL(dpm_suspend_end);
1317
1318/**
1319 * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
1320 * @dev: Device to suspend.
1321 * @state: PM transition of the system being carried out.
1322 * @cb: Suspend callback to execute.
1323 * @info: string description of caller.
1324 */
1325static int legacy_suspend(struct device *dev, pm_message_t state,
1326 int (*cb)(struct device *dev, pm_message_t state),
1327 char *info)
1328{
1329 int error;
1330 ktime_t calltime;
1331
1332 calltime = initcall_debug_start(dev);
1333
1334 trace_device_pm_callback_start(dev, info, state.event);
1335 error = cb(dev, state);
1336 trace_device_pm_callback_end(dev, error);
1337 suspend_report_result(cb, error);
1338
1339 initcall_debug_report(dev, calltime, error, state, info);
1340
1341 return error;
1342}
1343
1344/**
1345 * device_suspend - Execute "suspend" callbacks for given device.
1346 * @dev: Device to handle.
1347 * @state: PM transition of the system being carried out.
1348 * @async: If true, the device is being suspended asynchronously.
1349 */
1350static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1351{
1352 pm_callback_t callback = NULL;
1353 char *info = NULL;
1354 int error = 0;
1355 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
1356
1357 TRACE_DEVICE(dev);
1358 TRACE_SUSPEND(0);
1359
1360 dpm_wait_for_children(dev, async);
1361
1362 if (async_error)
1363 goto Complete;
1364
1365 /*
1366 * If a device configured to wake up the system from sleep states
1367 * has been suspended at run time and there's a resume request pending
1368 * for it, this is equivalent to the device signaling wakeup, so the
1369 * system suspend operation should be aborted.
1370 */
1371 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
1372 pm_wakeup_event(dev, 0);
1373
1374 if (pm_wakeup_pending()) {
1375 async_error = -EBUSY;
1376 goto Complete;
1377 }
1378
1379 if (dev->power.syscore)
1380 goto Complete;
1381
1382 if (dev->power.direct_complete) {
1383 if (pm_runtime_status_suspended(dev)) {
1384 pm_runtime_disable(dev);
1385 if (pm_runtime_status_suspended(dev))
1386 goto Complete;
1387
1388 pm_runtime_enable(dev);
1389 }
1390 dev->power.direct_complete = false;
1391 }
1392
1393 dpm_watchdog_set(&wd, dev);
1394 device_lock(dev);
1395
1396 if (dev->pm_domain) {
1397 info = "power domain ";
1398 callback = pm_op(&dev->pm_domain->ops, state);
1399 goto Run;
1400 }
1401
1402 if (dev->type && dev->type->pm) {
1403 info = "type ";
1404 callback = pm_op(dev->type->pm, state);
1405 goto Run;
1406 }
1407
1408 if (dev->class) {
1409 if (dev->class->pm) {
1410 info = "class ";
1411 callback = pm_op(dev->class->pm, state);
1412 goto Run;
1413 } else if (dev->class->suspend) {
1414 pm_dev_dbg(dev, state, "legacy class ");
1415 error = legacy_suspend(dev, state, dev->class->suspend,
1416 "legacy class ");
1417 goto End;
1418 }
1419 }
1420
1421 if (dev->bus) {
1422 if (dev->bus->pm) {
1423 info = "bus ";
1424 callback = pm_op(dev->bus->pm, state);
1425 } else if (dev->bus->suspend) {
1426 pm_dev_dbg(dev, state, "legacy bus ");
1427 error = legacy_suspend(dev, state, dev->bus->suspend,
1428 "legacy bus ");
1429 goto End;
1430 }
1431 }
1432
1433 Run:
1434 if (!callback && dev->driver && dev->driver->pm) {
1435 info = "driver ";
1436 callback = pm_op(dev->driver->pm, state);
1437 }
1438
1439 error = dpm_run_callback(callback, dev, state, info);
1440
1441 End:
1442 if (!error) {
1443 struct device *parent = dev->parent;
1444
1445 dev->power.is_suspended = true;
1446 if (parent) {
1447 spin_lock_irq(&parent->power.lock);
1448
1449 dev->parent->power.direct_complete = false;
1450 if (dev->power.wakeup_path
1451 && !dev->parent->power.ignore_children)
1452 dev->parent->power.wakeup_path = true;
1453
1454 spin_unlock_irq(&parent->power.lock);
1455 }
1456 }
1457
1458 device_unlock(dev);
1459 dpm_watchdog_clear(&wd);
1460
1461 Complete:
1462 complete_all(&dev->power.completion);
1463 if (error)
1464 async_error = error;
1465
1466 TRACE_SUSPEND(error);
1467 return error;
1468}
1469
1470static void async_suspend(void *data, async_cookie_t cookie)
1471{
1472 struct device *dev = (struct device *)data;
1473 int error;
1474
1475 error = __device_suspend(dev, pm_transition, true);
1476 if (error) {
1477 dpm_save_failed_dev(dev_name(dev));
1478 pm_dev_err(dev, pm_transition, " async", error);
1479 }
1480
1481 put_device(dev);
1482}
1483
1484static int device_suspend(struct device *dev)
1485{
1486 reinit_completion(&dev->power.completion);
1487
1488 if (is_async(dev)) {
1489 get_device(dev);
1490 async_schedule(async_suspend, dev);
1491 return 0;
1492 }
1493
1494 return __device_suspend(dev, pm_transition, false);
1495}
1496
1497/**
1498 * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
1499 * @state: PM transition of the system being carried out.
1500 */
1501int dpm_suspend(pm_message_t state)
1502{
1503 ktime_t starttime = ktime_get();
1504 int error = 0;
1505
1506 trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
1507 might_sleep();
1508
1509 cpufreq_suspend();
1510
1511 mutex_lock(&dpm_list_mtx);
1512 pm_transition = state;
1513 async_error = 0;
1514 while (!list_empty(&dpm_prepared_list)) {
1515 struct device *dev = to_device(dpm_prepared_list.prev);
1516
1517 get_device(dev);
1518 mutex_unlock(&dpm_list_mtx);
1519
1520 error = device_suspend(dev);
1521
1522 mutex_lock(&dpm_list_mtx);
1523 if (error) {
1524 pm_dev_err(dev, state, "", error);
1525 dpm_save_failed_dev(dev_name(dev));
1526 put_device(dev);
1527 break;
1528 }
1529 if (!list_empty(&dev->power.entry))
1530 list_move(&dev->power.entry, &dpm_suspended_list);
1531 put_device(dev);
1532 if (async_error)
1533 break;
1534 }
1535 mutex_unlock(&dpm_list_mtx);
1536 async_synchronize_full();
1537 if (!error)
1538 error = async_error;
1539 if (error) {
1540 suspend_stats.failed_suspend++;
1541 dpm_save_failed_step(SUSPEND_SUSPEND);
1542 } else
1543 dpm_show_time(starttime, state, NULL);
1544 trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
1545 return error;
1546}
1547
1548/**
1549 * device_prepare - Prepare a device for system power transition.
1550 * @dev: Device to handle.
1551 * @state: PM transition of the system being carried out.
1552 *
1553 * Execute the ->prepare() callback(s) for given device. No new children of the
1554 * device may be registered after this function has returned.
1555 */
1556static int device_prepare(struct device *dev, pm_message_t state)
1557{
1558 int (*callback)(struct device *) = NULL;
1559 char *info = NULL;
1560 int ret = 0;
1561
1562 if (dev->power.syscore)
1563 return 0;
1564
1565 /*
1566 * If a device's parent goes into runtime suspend at the wrong time,
1567 * it won't be possible to resume the device. To prevent this we
1568 * block runtime suspend here, during the prepare phase, and allow
1569 * it again during the complete phase.
1570 */
1571 pm_runtime_get_noresume(dev);
1572
1573 device_lock(dev);
1574
1575 dev->power.wakeup_path = device_may_wakeup(dev);
1576
1577 if (dev->power.no_pm_callbacks) {
1578 ret = 1; /* Let device go direct_complete */
1579 goto unlock;
1580 }
1581
1582 if (dev->pm_domain) {
1583 info = "preparing power domain ";
1584 callback = dev->pm_domain->ops.prepare;
1585 } else if (dev->type && dev->type->pm) {
1586 info = "preparing type ";
1587 callback = dev->type->pm->prepare;
1588 } else if (dev->class && dev->class->pm) {
1589 info = "preparing class ";
1590 callback = dev->class->pm->prepare;
1591 } else if (dev->bus && dev->bus->pm) {
1592 info = "preparing bus ";
1593 callback = dev->bus->pm->prepare;
1594 }
1595
1596 if (!callback && dev->driver && dev->driver->pm) {
1597 info = "preparing driver ";
1598 callback = dev->driver->pm->prepare;
1599 }
1600
1601 if (callback)
1602 ret = callback(dev);
1603
1604unlock:
1605 device_unlock(dev);
1606
1607 if (ret < 0) {
1608 suspend_report_result(callback, ret);
1609 pm_runtime_put(dev);
1610 return ret;
1611 }
1612 /*
1613 * A positive return value from ->prepare() means "this device appears
1614 * to be runtime-suspended and its state is fine, so if it really is
1615 * runtime-suspended, you can leave it in that state provided that you
1616 * will do the same thing with all of its descendants". This only
1617 * applies to suspend transitions, however.
1618 */
1619 spin_lock_irq(&dev->power.lock);
1620 dev->power.direct_complete = ret > 0 && state.event == PM_EVENT_SUSPEND;
1621 spin_unlock_irq(&dev->power.lock);
1622 return 0;
1623}
1624
1625/**
1626 * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1627 * @state: PM transition of the system being carried out.
1628 *
1629 * Execute the ->prepare() callback(s) for all devices.
1630 */
1631int dpm_prepare(pm_message_t state)
1632{
1633 int error = 0;
1634
1635 trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
1636 might_sleep();
1637
1638 /*
1639 * Give a chance for the known devices to complete their probes, before
1640 * disable probing of devices. This sync point is important at least
1641 * at boot time + hibernation restore.
1642 */
1643 wait_for_device_probe();
1644 /*
1645 * It is unsafe if probing of devices will happen during suspend or
1646 * hibernation and system behavior will be unpredictable in this case.
1647 * So, let's prohibit device's probing here and defer their probes
1648 * instead. The normal behavior will be restored in dpm_complete().
1649 */
1650 device_block_probing();
1651
1652 mutex_lock(&dpm_list_mtx);
1653 while (!list_empty(&dpm_list)) {
1654 struct device *dev = to_device(dpm_list.next);
1655
1656 get_device(dev);
1657 mutex_unlock(&dpm_list_mtx);
1658
1659 trace_device_pm_callback_start(dev, "", state.event);
1660 error = device_prepare(dev, state);
1661 trace_device_pm_callback_end(dev, error);
1662
1663 mutex_lock(&dpm_list_mtx);
1664 if (error) {
1665 if (error == -EAGAIN) {
1666 put_device(dev);
1667 error = 0;
1668 continue;
1669 }
1670 printk(KERN_INFO "PM: Device %s not prepared "
1671 "for power transition: code %d\n",
1672 dev_name(dev), error);
1673 put_device(dev);
1674 break;
1675 }
1676 dev->power.is_prepared = true;
1677 if (!list_empty(&dev->power.entry))
1678 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1679 put_device(dev);
1680 }
1681 mutex_unlock(&dpm_list_mtx);
1682 trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
1683 return error;
1684}
1685
1686/**
1687 * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1688 * @state: PM transition of the system being carried out.
1689 *
1690 * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1691 * callbacks for them.
1692 */
1693int dpm_suspend_start(pm_message_t state)
1694{
1695 int error;
1696
1697 error = dpm_prepare(state);
1698 if (error) {
1699 suspend_stats.failed_prepare++;
1700 dpm_save_failed_step(SUSPEND_PREPARE);
1701 } else
1702 error = dpm_suspend(state);
1703 return error;
1704}
1705EXPORT_SYMBOL_GPL(dpm_suspend_start);
1706
1707void __suspend_report_result(const char *function, void *fn, int ret)
1708{
1709 if (ret)
1710 printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
1711}
1712EXPORT_SYMBOL_GPL(__suspend_report_result);
1713
1714/**
1715 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1716 * @dev: Device to wait for.
1717 * @subordinate: Device that needs to wait for @dev.
1718 */
1719int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
1720{
1721 dpm_wait(dev, subordinate->power.async_suspend);
1722 return async_error;
1723}
1724EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
1725
1726/**
1727 * dpm_for_each_dev - device iterator.
1728 * @data: data for the callback.
1729 * @fn: function to be called for each device.
1730 *
1731 * Iterate over devices in dpm_list, and call @fn for each device,
1732 * passing it @data.
1733 */
1734void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
1735{
1736 struct device *dev;
1737
1738 if (!fn)
1739 return;
1740
1741 device_pm_lock();
1742 list_for_each_entry(dev, &dpm_list, power.entry)
1743 fn(dev, data);
1744 device_pm_unlock();
1745}
1746EXPORT_SYMBOL_GPL(dpm_for_each_dev);
1747
1748static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
1749{
1750 if (!ops)
1751 return true;
1752
1753 return !ops->prepare &&
1754 !ops->suspend &&
1755 !ops->suspend_late &&
1756 !ops->suspend_noirq &&
1757 !ops->resume_noirq &&
1758 !ops->resume_early &&
1759 !ops->resume &&
1760 !ops->complete;
1761}
1762
1763void device_pm_check_callbacks(struct device *dev)
1764{
1765 spin_lock_irq(&dev->power.lock);
1766 dev->power.no_pm_callbacks =
1767 (!dev->bus || pm_ops_is_empty(dev->bus->pm)) &&
1768 (!dev->class || pm_ops_is_empty(dev->class->pm)) &&
1769 (!dev->type || pm_ops_is_empty(dev->type->pm)) &&
1770 (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
1771 (!dev->driver || pm_ops_is_empty(dev->driver->pm));
1772 spin_unlock_irq(&dev->power.lock);
1773}