Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * drivers/base/power/wakeup.c - System wakeup events framework
4 *
5 * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
6 */
7#define pr_fmt(fmt) "PM: " fmt
8
9#include <linux/device.h>
10#include <linux/slab.h>
11#include <linux/sched/signal.h>
12#include <linux/capability.h>
13#include <linux/export.h>
14#include <linux/suspend.h>
15#include <linux/seq_file.h>
16#include <linux/debugfs.h>
17#include <linux/pm_wakeirq.h>
18#include <trace/events/power.h>
19
20#include "power.h"
21
22#define list_for_each_entry_rcu_locked(pos, head, member) \
23 list_for_each_entry_rcu(pos, head, member, \
24 srcu_read_lock_held(&wakeup_srcu))
25/*
26 * If set, the suspend/hibernate code will abort transitions to a sleep state
27 * if wakeup events are registered during or immediately before the transition.
28 */
29bool events_check_enabled __read_mostly;
30
31/* First wakeup IRQ seen by the kernel in the last cycle. */
32static unsigned int wakeup_irq[2] __read_mostly;
33static DEFINE_RAW_SPINLOCK(wakeup_irq_lock);
34
35/* If greater than 0 and the system is suspending, terminate the suspend. */
36static atomic_t pm_abort_suspend __read_mostly;
37
38/*
39 * Combined counters of registered wakeup events and wakeup events in progress.
40 * They need to be modified together atomically, so it's better to use one
41 * atomic variable to hold them both.
42 */
43static atomic_t combined_event_count = ATOMIC_INIT(0);
44
45#define IN_PROGRESS_BITS (sizeof(int) * 4)
46#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1)
47
48static void split_counters(unsigned int *cnt, unsigned int *inpr)
49{
50 unsigned int comb = atomic_read(&combined_event_count);
51
52 *cnt = (comb >> IN_PROGRESS_BITS);
53 *inpr = comb & MAX_IN_PROGRESS;
54}
55
56/* A preserved old value of the events counter. */
57static unsigned int saved_count;
58
59static DEFINE_RAW_SPINLOCK(events_lock);
60
61static void pm_wakeup_timer_fn(struct timer_list *t);
62
63static LIST_HEAD(wakeup_sources);
64
65static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
66
67DEFINE_STATIC_SRCU(wakeup_srcu);
68
69static struct wakeup_source deleted_ws = {
70 .name = "deleted",
71 .lock = __SPIN_LOCK_UNLOCKED(deleted_ws.lock),
72};
73
74static DEFINE_IDA(wakeup_ida);
75
76/**
77 * wakeup_source_create - Create a struct wakeup_source object.
78 * @name: Name of the new wakeup source.
79 */
80struct wakeup_source *wakeup_source_create(const char *name)
81{
82 struct wakeup_source *ws;
83 const char *ws_name;
84 int id;
85
86 ws = kzalloc(sizeof(*ws), GFP_KERNEL);
87 if (!ws)
88 goto err_ws;
89
90 ws_name = kstrdup_const(name, GFP_KERNEL);
91 if (!ws_name)
92 goto err_name;
93 ws->name = ws_name;
94
95 id = ida_alloc(&wakeup_ida, GFP_KERNEL);
96 if (id < 0)
97 goto err_id;
98 ws->id = id;
99
100 return ws;
101
102err_id:
103 kfree_const(ws->name);
104err_name:
105 kfree(ws);
106err_ws:
107 return NULL;
108}
109EXPORT_SYMBOL_GPL(wakeup_source_create);
110
111/*
112 * Record wakeup_source statistics being deleted into a dummy wakeup_source.
113 */
114static void wakeup_source_record(struct wakeup_source *ws)
115{
116 unsigned long flags;
117
118 spin_lock_irqsave(&deleted_ws.lock, flags);
119
120 if (ws->event_count) {
121 deleted_ws.total_time =
122 ktime_add(deleted_ws.total_time, ws->total_time);
123 deleted_ws.prevent_sleep_time =
124 ktime_add(deleted_ws.prevent_sleep_time,
125 ws->prevent_sleep_time);
126 deleted_ws.max_time =
127 ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ?
128 deleted_ws.max_time : ws->max_time;
129 deleted_ws.event_count += ws->event_count;
130 deleted_ws.active_count += ws->active_count;
131 deleted_ws.relax_count += ws->relax_count;
132 deleted_ws.expire_count += ws->expire_count;
133 deleted_ws.wakeup_count += ws->wakeup_count;
134 }
135
136 spin_unlock_irqrestore(&deleted_ws.lock, flags);
137}
138
139static void wakeup_source_free(struct wakeup_source *ws)
140{
141 ida_free(&wakeup_ida, ws->id);
142 kfree_const(ws->name);
143 kfree(ws);
144}
145
146/**
147 * wakeup_source_destroy - Destroy a struct wakeup_source object.
148 * @ws: Wakeup source to destroy.
149 *
150 * Use only for wakeup source objects created with wakeup_source_create().
151 */
152void wakeup_source_destroy(struct wakeup_source *ws)
153{
154 if (!ws)
155 return;
156
157 __pm_relax(ws);
158 wakeup_source_record(ws);
159 wakeup_source_free(ws);
160}
161EXPORT_SYMBOL_GPL(wakeup_source_destroy);
162
163/**
164 * wakeup_source_add - Add given object to the list of wakeup sources.
165 * @ws: Wakeup source object to add to the list.
166 */
167void wakeup_source_add(struct wakeup_source *ws)
168{
169 unsigned long flags;
170
171 if (WARN_ON(!ws))
172 return;
173
174 spin_lock_init(&ws->lock);
175 timer_setup(&ws->timer, pm_wakeup_timer_fn, 0);
176 ws->active = false;
177
178 raw_spin_lock_irqsave(&events_lock, flags);
179 list_add_rcu(&ws->entry, &wakeup_sources);
180 raw_spin_unlock_irqrestore(&events_lock, flags);
181}
182EXPORT_SYMBOL_GPL(wakeup_source_add);
183
184/**
185 * wakeup_source_remove - Remove given object from the wakeup sources list.
186 * @ws: Wakeup source object to remove from the list.
187 */
188void wakeup_source_remove(struct wakeup_source *ws)
189{
190 unsigned long flags;
191
192 if (WARN_ON(!ws))
193 return;
194
195 raw_spin_lock_irqsave(&events_lock, flags);
196 list_del_rcu(&ws->entry);
197 raw_spin_unlock_irqrestore(&events_lock, flags);
198 synchronize_srcu(&wakeup_srcu);
199
200 del_timer_sync(&ws->timer);
201 /*
202 * Clear timer.function to make wakeup_source_not_registered() treat
203 * this wakeup source as not registered.
204 */
205 ws->timer.function = NULL;
206}
207EXPORT_SYMBOL_GPL(wakeup_source_remove);
208
209/**
210 * wakeup_source_register - Create wakeup source and add it to the list.
211 * @dev: Device this wakeup source is associated with (or NULL if virtual).
212 * @name: Name of the wakeup source to register.
213 */
214struct wakeup_source *wakeup_source_register(struct device *dev,
215 const char *name)
216{
217 struct wakeup_source *ws;
218 int ret;
219
220 ws = wakeup_source_create(name);
221 if (ws) {
222 if (!dev || device_is_registered(dev)) {
223 ret = wakeup_source_sysfs_add(dev, ws);
224 if (ret) {
225 wakeup_source_free(ws);
226 return NULL;
227 }
228 }
229 wakeup_source_add(ws);
230 }
231 return ws;
232}
233EXPORT_SYMBOL_GPL(wakeup_source_register);
234
235/**
236 * wakeup_source_unregister - Remove wakeup source from the list and remove it.
237 * @ws: Wakeup source object to unregister.
238 */
239void wakeup_source_unregister(struct wakeup_source *ws)
240{
241 if (ws) {
242 wakeup_source_remove(ws);
243 if (ws->dev)
244 wakeup_source_sysfs_remove(ws);
245
246 wakeup_source_destroy(ws);
247 }
248}
249EXPORT_SYMBOL_GPL(wakeup_source_unregister);
250
251/**
252 * wakeup_sources_read_lock - Lock wakeup source list for read.
253 *
254 * Returns an index of srcu lock for struct wakeup_srcu.
255 * This index must be passed to the matching wakeup_sources_read_unlock().
256 */
257int wakeup_sources_read_lock(void)
258{
259 return srcu_read_lock(&wakeup_srcu);
260}
261EXPORT_SYMBOL_GPL(wakeup_sources_read_lock);
262
263/**
264 * wakeup_sources_read_unlock - Unlock wakeup source list.
265 * @idx: return value from corresponding wakeup_sources_read_lock()
266 */
267void wakeup_sources_read_unlock(int idx)
268{
269 srcu_read_unlock(&wakeup_srcu, idx);
270}
271EXPORT_SYMBOL_GPL(wakeup_sources_read_unlock);
272
273/**
274 * wakeup_sources_walk_start - Begin a walk on wakeup source list
275 *
276 * Returns first object of the list of wakeup sources.
277 *
278 * Note that to be safe, wakeup sources list needs to be locked by calling
279 * wakeup_source_read_lock() for this.
280 */
281struct wakeup_source *wakeup_sources_walk_start(void)
282{
283 struct list_head *ws_head = &wakeup_sources;
284
285 return list_entry_rcu(ws_head->next, struct wakeup_source, entry);
286}
287EXPORT_SYMBOL_GPL(wakeup_sources_walk_start);
288
289/**
290 * wakeup_sources_walk_next - Get next wakeup source from the list
291 * @ws: Previous wakeup source object
292 *
293 * Note that to be safe, wakeup sources list needs to be locked by calling
294 * wakeup_source_read_lock() for this.
295 */
296struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws)
297{
298 struct list_head *ws_head = &wakeup_sources;
299
300 return list_next_or_null_rcu(ws_head, &ws->entry,
301 struct wakeup_source, entry);
302}
303EXPORT_SYMBOL_GPL(wakeup_sources_walk_next);
304
305/**
306 * device_wakeup_attach - Attach a wakeup source object to a device object.
307 * @dev: Device to handle.
308 * @ws: Wakeup source object to attach to @dev.
309 *
310 * This causes @dev to be treated as a wakeup device.
311 */
312static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
313{
314 spin_lock_irq(&dev->power.lock);
315 if (dev->power.wakeup) {
316 spin_unlock_irq(&dev->power.lock);
317 return -EEXIST;
318 }
319 dev->power.wakeup = ws;
320 if (dev->power.wakeirq)
321 device_wakeup_attach_irq(dev, dev->power.wakeirq);
322 spin_unlock_irq(&dev->power.lock);
323 return 0;
324}
325
326/**
327 * device_wakeup_enable - Enable given device to be a wakeup source.
328 * @dev: Device to handle.
329 *
330 * Create a wakeup source object, register it and attach it to @dev.
331 */
332int device_wakeup_enable(struct device *dev)
333{
334 struct wakeup_source *ws;
335 int ret;
336
337 if (!dev || !dev->power.can_wakeup)
338 return -EINVAL;
339
340 if (pm_suspend_target_state != PM_SUSPEND_ON)
341 dev_dbg(dev, "Suspicious %s() during system transition!\n", __func__);
342
343 ws = wakeup_source_register(dev, dev_name(dev));
344 if (!ws)
345 return -ENOMEM;
346
347 ret = device_wakeup_attach(dev, ws);
348 if (ret)
349 wakeup_source_unregister(ws);
350
351 return ret;
352}
353EXPORT_SYMBOL_GPL(device_wakeup_enable);
354
355/**
356 * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source
357 * @dev: Device to handle
358 * @wakeirq: Device specific wakeirq entry
359 *
360 * Attach a device wakeirq to the wakeup source so the device
361 * wake IRQ can be configured automatically for suspend and
362 * resume.
363 *
364 * Call under the device's power.lock lock.
365 */
366void device_wakeup_attach_irq(struct device *dev,
367 struct wake_irq *wakeirq)
368{
369 struct wakeup_source *ws;
370
371 ws = dev->power.wakeup;
372 if (!ws)
373 return;
374
375 if (ws->wakeirq)
376 dev_err(dev, "Leftover wakeup IRQ found, overriding\n");
377
378 ws->wakeirq = wakeirq;
379}
380
381/**
382 * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source
383 * @dev: Device to handle
384 *
385 * Removes a device wakeirq from the wakeup source.
386 *
387 * Call under the device's power.lock lock.
388 */
389void device_wakeup_detach_irq(struct device *dev)
390{
391 struct wakeup_source *ws;
392
393 ws = dev->power.wakeup;
394 if (ws)
395 ws->wakeirq = NULL;
396}
397
398/**
399 * device_wakeup_arm_wake_irqs -
400 *
401 * Iterates over the list of device wakeirqs to arm them.
402 */
403void device_wakeup_arm_wake_irqs(void)
404{
405 struct wakeup_source *ws;
406 int srcuidx;
407
408 srcuidx = srcu_read_lock(&wakeup_srcu);
409 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry)
410 dev_pm_arm_wake_irq(ws->wakeirq);
411 srcu_read_unlock(&wakeup_srcu, srcuidx);
412}
413
414/**
415 * device_wakeup_disarm_wake_irqs -
416 *
417 * Iterates over the list of device wakeirqs to disarm them.
418 */
419void device_wakeup_disarm_wake_irqs(void)
420{
421 struct wakeup_source *ws;
422 int srcuidx;
423
424 srcuidx = srcu_read_lock(&wakeup_srcu);
425 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry)
426 dev_pm_disarm_wake_irq(ws->wakeirq);
427 srcu_read_unlock(&wakeup_srcu, srcuidx);
428}
429
430/**
431 * device_wakeup_detach - Detach a device's wakeup source object from it.
432 * @dev: Device to detach the wakeup source object from.
433 *
434 * After it returns, @dev will not be treated as a wakeup device any more.
435 */
436static struct wakeup_source *device_wakeup_detach(struct device *dev)
437{
438 struct wakeup_source *ws;
439
440 spin_lock_irq(&dev->power.lock);
441 ws = dev->power.wakeup;
442 dev->power.wakeup = NULL;
443 spin_unlock_irq(&dev->power.lock);
444 return ws;
445}
446
447/**
448 * device_wakeup_disable - Do not regard a device as a wakeup source any more.
449 * @dev: Device to handle.
450 *
451 * Detach the @dev's wakeup source object from it, unregister this wakeup source
452 * object and destroy it.
453 */
454void device_wakeup_disable(struct device *dev)
455{
456 struct wakeup_source *ws;
457
458 if (!dev || !dev->power.can_wakeup)
459 return;
460
461 ws = device_wakeup_detach(dev);
462 wakeup_source_unregister(ws);
463}
464EXPORT_SYMBOL_GPL(device_wakeup_disable);
465
466/**
467 * device_set_wakeup_capable - Set/reset device wakeup capability flag.
468 * @dev: Device to handle.
469 * @capable: Whether or not @dev is capable of waking up the system from sleep.
470 *
471 * If @capable is set, set the @dev's power.can_wakeup flag and add its
472 * wakeup-related attributes to sysfs. Otherwise, unset the @dev's
473 * power.can_wakeup flag and remove its wakeup-related attributes from sysfs.
474 *
475 * This function may sleep and it can't be called from any context where
476 * sleeping is not allowed.
477 */
478void device_set_wakeup_capable(struct device *dev, bool capable)
479{
480 if (!!dev->power.can_wakeup == !!capable)
481 return;
482
483 dev->power.can_wakeup = capable;
484 if (device_is_registered(dev) && !list_empty(&dev->power.entry)) {
485 if (capable) {
486 int ret = wakeup_sysfs_add(dev);
487
488 if (ret)
489 dev_info(dev, "Wakeup sysfs attributes not added\n");
490 } else {
491 wakeup_sysfs_remove(dev);
492 }
493 }
494}
495EXPORT_SYMBOL_GPL(device_set_wakeup_capable);
496
497/**
498 * device_set_wakeup_enable - Enable or disable a device to wake up the system.
499 * @dev: Device to handle.
500 * @enable: enable/disable flag
501 */
502int device_set_wakeup_enable(struct device *dev, bool enable)
503{
504 if (enable)
505 return device_wakeup_enable(dev);
506
507 device_wakeup_disable(dev);
508 return 0;
509}
510EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
511
512/**
513 * wakeup_source_not_registered - validate the given wakeup source.
514 * @ws: Wakeup source to be validated.
515 */
516static bool wakeup_source_not_registered(struct wakeup_source *ws)
517{
518 /*
519 * Use timer struct to check if the given source is initialized
520 * by wakeup_source_add.
521 */
522 return ws->timer.function != pm_wakeup_timer_fn;
523}
524
525/*
526 * The functions below use the observation that each wakeup event starts a
527 * period in which the system should not be suspended. The moment this period
528 * will end depends on how the wakeup event is going to be processed after being
529 * detected and all of the possible cases can be divided into two distinct
530 * groups.
531 *
532 * First, a wakeup event may be detected by the same functional unit that will
533 * carry out the entire processing of it and possibly will pass it to user space
534 * for further processing. In that case the functional unit that has detected
535 * the event may later "close" the "no suspend" period associated with it
536 * directly as soon as it has been dealt with. The pair of pm_stay_awake() and
537 * pm_relax(), balanced with each other, is supposed to be used in such
538 * situations.
539 *
540 * Second, a wakeup event may be detected by one functional unit and processed
541 * by another one. In that case the unit that has detected it cannot really
542 * "close" the "no suspend" period associated with it, unless it knows in
543 * advance what's going to happen to the event during processing. This
544 * knowledge, however, may not be available to it, so it can simply specify time
545 * to wait before the system can be suspended and pass it as the second
546 * argument of pm_wakeup_event().
547 *
548 * It is valid to call pm_relax() after pm_wakeup_event(), in which case the
549 * "no suspend" period will be ended either by the pm_relax(), or by the timer
550 * function executed when the timer expires, whichever comes first.
551 */
552
553/**
554 * wakeup_source_activate - Mark given wakeup source as active.
555 * @ws: Wakeup source to handle.
556 *
557 * Update the @ws' statistics and, if @ws has just been activated, notify the PM
558 * core of the event by incrementing the counter of the wakeup events being
559 * processed.
560 */
561static void wakeup_source_activate(struct wakeup_source *ws)
562{
563 unsigned int cec;
564
565 if (WARN_ONCE(wakeup_source_not_registered(ws),
566 "unregistered wakeup source\n"))
567 return;
568
569 ws->active = true;
570 ws->active_count++;
571 ws->last_time = ktime_get();
572 if (ws->autosleep_enabled)
573 ws->start_prevent_time = ws->last_time;
574
575 /* Increment the counter of events in progress. */
576 cec = atomic_inc_return(&combined_event_count);
577
578 trace_wakeup_source_activate(ws->name, cec);
579}
580
581/**
582 * wakeup_source_report_event - Report wakeup event using the given source.
583 * @ws: Wakeup source to report the event for.
584 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
585 */
586static void wakeup_source_report_event(struct wakeup_source *ws, bool hard)
587{
588 ws->event_count++;
589 /* This is racy, but the counter is approximate anyway. */
590 if (events_check_enabled)
591 ws->wakeup_count++;
592
593 if (!ws->active)
594 wakeup_source_activate(ws);
595
596 if (hard)
597 pm_system_wakeup();
598}
599
600/**
601 * __pm_stay_awake - Notify the PM core of a wakeup event.
602 * @ws: Wakeup source object associated with the source of the event.
603 *
604 * It is safe to call this function from interrupt context.
605 */
606void __pm_stay_awake(struct wakeup_source *ws)
607{
608 unsigned long flags;
609
610 if (!ws)
611 return;
612
613 spin_lock_irqsave(&ws->lock, flags);
614
615 wakeup_source_report_event(ws, false);
616 del_timer(&ws->timer);
617 ws->timer_expires = 0;
618
619 spin_unlock_irqrestore(&ws->lock, flags);
620}
621EXPORT_SYMBOL_GPL(__pm_stay_awake);
622
623/**
624 * pm_stay_awake - Notify the PM core that a wakeup event is being processed.
625 * @dev: Device the wakeup event is related to.
626 *
627 * Notify the PM core of a wakeup event (signaled by @dev) by calling
628 * __pm_stay_awake for the @dev's wakeup source object.
629 *
630 * Call this function after detecting of a wakeup event if pm_relax() is going
631 * to be called directly after processing the event (and possibly passing it to
632 * user space for further processing).
633 */
634void pm_stay_awake(struct device *dev)
635{
636 unsigned long flags;
637
638 if (!dev)
639 return;
640
641 spin_lock_irqsave(&dev->power.lock, flags);
642 __pm_stay_awake(dev->power.wakeup);
643 spin_unlock_irqrestore(&dev->power.lock, flags);
644}
645EXPORT_SYMBOL_GPL(pm_stay_awake);
646
647#ifdef CONFIG_PM_AUTOSLEEP
648static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now)
649{
650 ktime_t delta = ktime_sub(now, ws->start_prevent_time);
651 ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta);
652}
653#else
654static inline void update_prevent_sleep_time(struct wakeup_source *ws,
655 ktime_t now) {}
656#endif
657
658/**
659 * wakeup_source_deactivate - Mark given wakeup source as inactive.
660 * @ws: Wakeup source to handle.
661 *
662 * Update the @ws' statistics and notify the PM core that the wakeup source has
663 * become inactive by decrementing the counter of wakeup events being processed
664 * and incrementing the counter of registered wakeup events.
665 */
666static void wakeup_source_deactivate(struct wakeup_source *ws)
667{
668 unsigned int cnt, inpr, cec;
669 ktime_t duration;
670 ktime_t now;
671
672 ws->relax_count++;
673 /*
674 * __pm_relax() may be called directly or from a timer function.
675 * If it is called directly right after the timer function has been
676 * started, but before the timer function calls __pm_relax(), it is
677 * possible that __pm_stay_awake() will be called in the meantime and
678 * will set ws->active. Then, ws->active may be cleared immediately
679 * by the __pm_relax() called from the timer function, but in such a
680 * case ws->relax_count will be different from ws->active_count.
681 */
682 if (ws->relax_count != ws->active_count) {
683 ws->relax_count--;
684 return;
685 }
686
687 ws->active = false;
688
689 now = ktime_get();
690 duration = ktime_sub(now, ws->last_time);
691 ws->total_time = ktime_add(ws->total_time, duration);
692 if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
693 ws->max_time = duration;
694
695 ws->last_time = now;
696 del_timer(&ws->timer);
697 ws->timer_expires = 0;
698
699 if (ws->autosleep_enabled)
700 update_prevent_sleep_time(ws, now);
701
702 /*
703 * Increment the counter of registered wakeup events and decrement the
704 * counter of wakeup events in progress simultaneously.
705 */
706 cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count);
707 trace_wakeup_source_deactivate(ws->name, cec);
708
709 split_counters(&cnt, &inpr);
710 if (!inpr && waitqueue_active(&wakeup_count_wait_queue))
711 wake_up(&wakeup_count_wait_queue);
712}
713
714/**
715 * __pm_relax - Notify the PM core that processing of a wakeup event has ended.
716 * @ws: Wakeup source object associated with the source of the event.
717 *
718 * Call this function for wakeup events whose processing started with calling
719 * __pm_stay_awake().
720 *
721 * It is safe to call it from interrupt context.
722 */
723void __pm_relax(struct wakeup_source *ws)
724{
725 unsigned long flags;
726
727 if (!ws)
728 return;
729
730 spin_lock_irqsave(&ws->lock, flags);
731 if (ws->active)
732 wakeup_source_deactivate(ws);
733 spin_unlock_irqrestore(&ws->lock, flags);
734}
735EXPORT_SYMBOL_GPL(__pm_relax);
736
737/**
738 * pm_relax - Notify the PM core that processing of a wakeup event has ended.
739 * @dev: Device that signaled the event.
740 *
741 * Execute __pm_relax() for the @dev's wakeup source object.
742 */
743void pm_relax(struct device *dev)
744{
745 unsigned long flags;
746
747 if (!dev)
748 return;
749
750 spin_lock_irqsave(&dev->power.lock, flags);
751 __pm_relax(dev->power.wakeup);
752 spin_unlock_irqrestore(&dev->power.lock, flags);
753}
754EXPORT_SYMBOL_GPL(pm_relax);
755
756/**
757 * pm_wakeup_timer_fn - Delayed finalization of a wakeup event.
758 * @t: timer list
759 *
760 * Call wakeup_source_deactivate() for the wakeup source whose address is stored
761 * in @data if it is currently active and its timer has not been canceled and
762 * the expiration time of the timer is not in future.
763 */
764static void pm_wakeup_timer_fn(struct timer_list *t)
765{
766 struct wakeup_source *ws = from_timer(ws, t, timer);
767 unsigned long flags;
768
769 spin_lock_irqsave(&ws->lock, flags);
770
771 if (ws->active && ws->timer_expires
772 && time_after_eq(jiffies, ws->timer_expires)) {
773 wakeup_source_deactivate(ws);
774 ws->expire_count++;
775 }
776
777 spin_unlock_irqrestore(&ws->lock, flags);
778}
779
780/**
781 * pm_wakeup_ws_event - Notify the PM core of a wakeup event.
782 * @ws: Wakeup source object associated with the event source.
783 * @msec: Anticipated event processing time (in milliseconds).
784 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
785 *
786 * Notify the PM core of a wakeup event whose source is @ws that will take
787 * approximately @msec milliseconds to be processed by the kernel. If @ws is
788 * not active, activate it. If @msec is nonzero, set up the @ws' timer to
789 * execute pm_wakeup_timer_fn() in future.
790 *
791 * It is safe to call this function from interrupt context.
792 */
793void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard)
794{
795 unsigned long flags;
796 unsigned long expires;
797
798 if (!ws)
799 return;
800
801 spin_lock_irqsave(&ws->lock, flags);
802
803 wakeup_source_report_event(ws, hard);
804
805 if (!msec) {
806 wakeup_source_deactivate(ws);
807 goto unlock;
808 }
809
810 expires = jiffies + msecs_to_jiffies(msec);
811 if (!expires)
812 expires = 1;
813
814 if (!ws->timer_expires || time_after(expires, ws->timer_expires)) {
815 mod_timer(&ws->timer, expires);
816 ws->timer_expires = expires;
817 }
818
819 unlock:
820 spin_unlock_irqrestore(&ws->lock, flags);
821}
822EXPORT_SYMBOL_GPL(pm_wakeup_ws_event);
823
824/**
825 * pm_wakeup_dev_event - Notify the PM core of a wakeup event.
826 * @dev: Device the wakeup event is related to.
827 * @msec: Anticipated event processing time (in milliseconds).
828 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
829 *
830 * Call pm_wakeup_ws_event() for the @dev's wakeup source object.
831 */
832void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard)
833{
834 unsigned long flags;
835
836 if (!dev)
837 return;
838
839 spin_lock_irqsave(&dev->power.lock, flags);
840 pm_wakeup_ws_event(dev->power.wakeup, msec, hard);
841 spin_unlock_irqrestore(&dev->power.lock, flags);
842}
843EXPORT_SYMBOL_GPL(pm_wakeup_dev_event);
844
845void pm_print_active_wakeup_sources(void)
846{
847 struct wakeup_source *ws;
848 int srcuidx, active = 0;
849 struct wakeup_source *last_activity_ws = NULL;
850
851 srcuidx = srcu_read_lock(&wakeup_srcu);
852 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
853 if (ws->active) {
854 pm_pr_dbg("active wakeup source: %s\n", ws->name);
855 active = 1;
856 } else if (!active &&
857 (!last_activity_ws ||
858 ktime_to_ns(ws->last_time) >
859 ktime_to_ns(last_activity_ws->last_time))) {
860 last_activity_ws = ws;
861 }
862 }
863
864 if (!active && last_activity_ws)
865 pm_pr_dbg("last active wakeup source: %s\n",
866 last_activity_ws->name);
867 srcu_read_unlock(&wakeup_srcu, srcuidx);
868}
869EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources);
870
871/**
872 * pm_wakeup_pending - Check if power transition in progress should be aborted.
873 *
874 * Compare the current number of registered wakeup events with its preserved
875 * value from the past and return true if new wakeup events have been registered
876 * since the old value was stored. Also return true if the current number of
877 * wakeup events being processed is different from zero.
878 */
879bool pm_wakeup_pending(void)
880{
881 unsigned long flags;
882 bool ret = false;
883
884 raw_spin_lock_irqsave(&events_lock, flags);
885 if (events_check_enabled) {
886 unsigned int cnt, inpr;
887
888 split_counters(&cnt, &inpr);
889 ret = (cnt != saved_count || inpr > 0);
890 events_check_enabled = !ret;
891 }
892 raw_spin_unlock_irqrestore(&events_lock, flags);
893
894 if (ret) {
895 pm_pr_dbg("Wakeup pending, aborting suspend\n");
896 pm_print_active_wakeup_sources();
897 }
898
899 return ret || atomic_read(&pm_abort_suspend) > 0;
900}
901EXPORT_SYMBOL_GPL(pm_wakeup_pending);
902
903void pm_system_wakeup(void)
904{
905 atomic_inc(&pm_abort_suspend);
906 s2idle_wake();
907}
908EXPORT_SYMBOL_GPL(pm_system_wakeup);
909
910void pm_system_cancel_wakeup(void)
911{
912 atomic_dec_if_positive(&pm_abort_suspend);
913}
914
915void pm_wakeup_clear(unsigned int irq_number)
916{
917 raw_spin_lock_irq(&wakeup_irq_lock);
918
919 if (irq_number && wakeup_irq[0] == irq_number)
920 wakeup_irq[0] = wakeup_irq[1];
921 else
922 wakeup_irq[0] = 0;
923
924 wakeup_irq[1] = 0;
925
926 raw_spin_unlock_irq(&wakeup_irq_lock);
927
928 if (!irq_number)
929 atomic_set(&pm_abort_suspend, 0);
930}
931
932void pm_system_irq_wakeup(unsigned int irq_number)
933{
934 unsigned long flags;
935
936 raw_spin_lock_irqsave(&wakeup_irq_lock, flags);
937
938 if (wakeup_irq[0] == 0)
939 wakeup_irq[0] = irq_number;
940 else if (wakeup_irq[1] == 0)
941 wakeup_irq[1] = irq_number;
942 else
943 irq_number = 0;
944
945 pm_pr_dbg("Triggering wakeup from IRQ %d\n", irq_number);
946
947 raw_spin_unlock_irqrestore(&wakeup_irq_lock, flags);
948
949 if (irq_number)
950 pm_system_wakeup();
951}
952
953unsigned int pm_wakeup_irq(void)
954{
955 return wakeup_irq[0];
956}
957
958/**
959 * pm_get_wakeup_count - Read the number of registered wakeup events.
960 * @count: Address to store the value at.
961 * @block: Whether or not to block.
962 *
963 * Store the number of registered wakeup events at the address in @count. If
964 * @block is set, block until the current number of wakeup events being
965 * processed is zero.
966 *
967 * Return 'false' if the current number of wakeup events being processed is
968 * nonzero. Otherwise return 'true'.
969 */
970bool pm_get_wakeup_count(unsigned int *count, bool block)
971{
972 unsigned int cnt, inpr;
973
974 if (block) {
975 DEFINE_WAIT(wait);
976
977 for (;;) {
978 prepare_to_wait(&wakeup_count_wait_queue, &wait,
979 TASK_INTERRUPTIBLE);
980 split_counters(&cnt, &inpr);
981 if (inpr == 0 || signal_pending(current))
982 break;
983 pm_print_active_wakeup_sources();
984 schedule();
985 }
986 finish_wait(&wakeup_count_wait_queue, &wait);
987 }
988
989 split_counters(&cnt, &inpr);
990 *count = cnt;
991 return !inpr;
992}
993
994/**
995 * pm_save_wakeup_count - Save the current number of registered wakeup events.
996 * @count: Value to compare with the current number of registered wakeup events.
997 *
998 * If @count is equal to the current number of registered wakeup events and the
999 * current number of wakeup events being processed is zero, store @count as the
1000 * old number of registered wakeup events for pm_check_wakeup_events(), enable
1001 * wakeup events detection and return 'true'. Otherwise disable wakeup events
1002 * detection and return 'false'.
1003 */
1004bool pm_save_wakeup_count(unsigned int count)
1005{
1006 unsigned int cnt, inpr;
1007 unsigned long flags;
1008
1009 events_check_enabled = false;
1010 raw_spin_lock_irqsave(&events_lock, flags);
1011 split_counters(&cnt, &inpr);
1012 if (cnt == count && inpr == 0) {
1013 saved_count = count;
1014 events_check_enabled = true;
1015 }
1016 raw_spin_unlock_irqrestore(&events_lock, flags);
1017 return events_check_enabled;
1018}
1019
1020#ifdef CONFIG_PM_AUTOSLEEP
1021/**
1022 * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources.
1023 * @set: Whether to set or to clear the autosleep_enabled flags.
1024 */
1025void pm_wakep_autosleep_enabled(bool set)
1026{
1027 struct wakeup_source *ws;
1028 ktime_t now = ktime_get();
1029 int srcuidx;
1030
1031 srcuidx = srcu_read_lock(&wakeup_srcu);
1032 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
1033 spin_lock_irq(&ws->lock);
1034 if (ws->autosleep_enabled != set) {
1035 ws->autosleep_enabled = set;
1036 if (ws->active) {
1037 if (set)
1038 ws->start_prevent_time = now;
1039 else
1040 update_prevent_sleep_time(ws, now);
1041 }
1042 }
1043 spin_unlock_irq(&ws->lock);
1044 }
1045 srcu_read_unlock(&wakeup_srcu, srcuidx);
1046}
1047#endif /* CONFIG_PM_AUTOSLEEP */
1048
1049/**
1050 * print_wakeup_source_stats - Print wakeup source statistics information.
1051 * @m: seq_file to print the statistics into.
1052 * @ws: Wakeup source object to print the statistics for.
1053 */
1054static int print_wakeup_source_stats(struct seq_file *m,
1055 struct wakeup_source *ws)
1056{
1057 unsigned long flags;
1058 ktime_t total_time;
1059 ktime_t max_time;
1060 unsigned long active_count;
1061 ktime_t active_time;
1062 ktime_t prevent_sleep_time;
1063
1064 spin_lock_irqsave(&ws->lock, flags);
1065
1066 total_time = ws->total_time;
1067 max_time = ws->max_time;
1068 prevent_sleep_time = ws->prevent_sleep_time;
1069 active_count = ws->active_count;
1070 if (ws->active) {
1071 ktime_t now = ktime_get();
1072
1073 active_time = ktime_sub(now, ws->last_time);
1074 total_time = ktime_add(total_time, active_time);
1075 if (active_time > max_time)
1076 max_time = active_time;
1077
1078 if (ws->autosleep_enabled)
1079 prevent_sleep_time = ktime_add(prevent_sleep_time,
1080 ktime_sub(now, ws->start_prevent_time));
1081 } else {
1082 active_time = 0;
1083 }
1084
1085 seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n",
1086 ws->name, active_count, ws->event_count,
1087 ws->wakeup_count, ws->expire_count,
1088 ktime_to_ms(active_time), ktime_to_ms(total_time),
1089 ktime_to_ms(max_time), ktime_to_ms(ws->last_time),
1090 ktime_to_ms(prevent_sleep_time));
1091
1092 spin_unlock_irqrestore(&ws->lock, flags);
1093
1094 return 0;
1095}
1096
1097static void *wakeup_sources_stats_seq_start(struct seq_file *m,
1098 loff_t *pos)
1099{
1100 struct wakeup_source *ws;
1101 loff_t n = *pos;
1102 int *srcuidx = m->private;
1103
1104 if (n == 0) {
1105 seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"
1106 "expire_count\tactive_since\ttotal_time\tmax_time\t"
1107 "last_change\tprevent_suspend_time\n");
1108 }
1109
1110 *srcuidx = srcu_read_lock(&wakeup_srcu);
1111 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
1112 if (n-- <= 0)
1113 return ws;
1114 }
1115
1116 return NULL;
1117}
1118
1119static void *wakeup_sources_stats_seq_next(struct seq_file *m,
1120 void *v, loff_t *pos)
1121{
1122 struct wakeup_source *ws = v;
1123 struct wakeup_source *next_ws = NULL;
1124
1125 ++(*pos);
1126
1127 list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) {
1128 next_ws = ws;
1129 break;
1130 }
1131
1132 if (!next_ws)
1133 print_wakeup_source_stats(m, &deleted_ws);
1134
1135 return next_ws;
1136}
1137
1138static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v)
1139{
1140 int *srcuidx = m->private;
1141
1142 srcu_read_unlock(&wakeup_srcu, *srcuidx);
1143}
1144
1145/**
1146 * wakeup_sources_stats_seq_show - Print wakeup sources statistics information.
1147 * @m: seq_file to print the statistics into.
1148 * @v: wakeup_source of each iteration
1149 */
1150static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v)
1151{
1152 struct wakeup_source *ws = v;
1153
1154 print_wakeup_source_stats(m, ws);
1155
1156 return 0;
1157}
1158
1159static const struct seq_operations wakeup_sources_stats_seq_ops = {
1160 .start = wakeup_sources_stats_seq_start,
1161 .next = wakeup_sources_stats_seq_next,
1162 .stop = wakeup_sources_stats_seq_stop,
1163 .show = wakeup_sources_stats_seq_show,
1164};
1165
1166static int wakeup_sources_stats_open(struct inode *inode, struct file *file)
1167{
1168 return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int));
1169}
1170
1171static const struct file_operations wakeup_sources_stats_fops = {
1172 .owner = THIS_MODULE,
1173 .open = wakeup_sources_stats_open,
1174 .read = seq_read,
1175 .llseek = seq_lseek,
1176 .release = seq_release_private,
1177};
1178
1179static int __init wakeup_sources_debugfs_init(void)
1180{
1181 debugfs_create_file("wakeup_sources", 0444, NULL, NULL,
1182 &wakeup_sources_stats_fops);
1183 return 0;
1184}
1185
1186postcore_initcall(wakeup_sources_debugfs_init);
1/*
2 * drivers/base/power/wakeup.c - System wakeup events framework
3 *
4 * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5 *
6 * This file is released under the GPLv2.
7 */
8
9#include <linux/device.h>
10#include <linux/slab.h>
11#include <linux/sched.h>
12#include <linux/capability.h>
13#include <linux/export.h>
14#include <linux/suspend.h>
15#include <linux/seq_file.h>
16#include <linux/debugfs.h>
17#include <linux/pm_wakeirq.h>
18#include <trace/events/power.h>
19
20#include "power.h"
21
22/*
23 * If set, the suspend/hibernate code will abort transitions to a sleep state
24 * if wakeup events are registered during or immediately before the transition.
25 */
26bool events_check_enabled __read_mostly;
27
28/* First wakeup IRQ seen by the kernel in the last cycle. */
29unsigned int pm_wakeup_irq __read_mostly;
30
31/* If set and the system is suspending, terminate the suspend. */
32static bool pm_abort_suspend __read_mostly;
33
34/*
35 * Combined counters of registered wakeup events and wakeup events in progress.
36 * They need to be modified together atomically, so it's better to use one
37 * atomic variable to hold them both.
38 */
39static atomic_t combined_event_count = ATOMIC_INIT(0);
40
41#define IN_PROGRESS_BITS (sizeof(int) * 4)
42#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1)
43
44static void split_counters(unsigned int *cnt, unsigned int *inpr)
45{
46 unsigned int comb = atomic_read(&combined_event_count);
47
48 *cnt = (comb >> IN_PROGRESS_BITS);
49 *inpr = comb & MAX_IN_PROGRESS;
50}
51
52/* A preserved old value of the events counter. */
53static unsigned int saved_count;
54
55static DEFINE_SPINLOCK(events_lock);
56
57static void pm_wakeup_timer_fn(unsigned long data);
58
59static LIST_HEAD(wakeup_sources);
60
61static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
62
63static struct wakeup_source deleted_ws = {
64 .name = "deleted",
65 .lock = __SPIN_LOCK_UNLOCKED(deleted_ws.lock),
66};
67
68/**
69 * wakeup_source_prepare - Prepare a new wakeup source for initialization.
70 * @ws: Wakeup source to prepare.
71 * @name: Pointer to the name of the new wakeup source.
72 *
73 * Callers must ensure that the @name string won't be freed when @ws is still in
74 * use.
75 */
76void wakeup_source_prepare(struct wakeup_source *ws, const char *name)
77{
78 if (ws) {
79 memset(ws, 0, sizeof(*ws));
80 ws->name = name;
81 }
82}
83EXPORT_SYMBOL_GPL(wakeup_source_prepare);
84
85/**
86 * wakeup_source_create - Create a struct wakeup_source object.
87 * @name: Name of the new wakeup source.
88 */
89struct wakeup_source *wakeup_source_create(const char *name)
90{
91 struct wakeup_source *ws;
92
93 ws = kmalloc(sizeof(*ws), GFP_KERNEL);
94 if (!ws)
95 return NULL;
96
97 wakeup_source_prepare(ws, name ? kstrdup_const(name, GFP_KERNEL) : NULL);
98 return ws;
99}
100EXPORT_SYMBOL_GPL(wakeup_source_create);
101
102/**
103 * wakeup_source_drop - Prepare a struct wakeup_source object for destruction.
104 * @ws: Wakeup source to prepare for destruction.
105 *
106 * Callers must ensure that __pm_stay_awake() or __pm_wakeup_event() will never
107 * be run in parallel with this function for the same wakeup source object.
108 */
109void wakeup_source_drop(struct wakeup_source *ws)
110{
111 if (!ws)
112 return;
113
114 del_timer_sync(&ws->timer);
115 __pm_relax(ws);
116}
117EXPORT_SYMBOL_GPL(wakeup_source_drop);
118
119/*
120 * Record wakeup_source statistics being deleted into a dummy wakeup_source.
121 */
122static void wakeup_source_record(struct wakeup_source *ws)
123{
124 unsigned long flags;
125
126 spin_lock_irqsave(&deleted_ws.lock, flags);
127
128 if (ws->event_count) {
129 deleted_ws.total_time =
130 ktime_add(deleted_ws.total_time, ws->total_time);
131 deleted_ws.prevent_sleep_time =
132 ktime_add(deleted_ws.prevent_sleep_time,
133 ws->prevent_sleep_time);
134 deleted_ws.max_time =
135 ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ?
136 deleted_ws.max_time : ws->max_time;
137 deleted_ws.event_count += ws->event_count;
138 deleted_ws.active_count += ws->active_count;
139 deleted_ws.relax_count += ws->relax_count;
140 deleted_ws.expire_count += ws->expire_count;
141 deleted_ws.wakeup_count += ws->wakeup_count;
142 }
143
144 spin_unlock_irqrestore(&deleted_ws.lock, flags);
145}
146
147/**
148 * wakeup_source_destroy - Destroy a struct wakeup_source object.
149 * @ws: Wakeup source to destroy.
150 *
151 * Use only for wakeup source objects created with wakeup_source_create().
152 */
153void wakeup_source_destroy(struct wakeup_source *ws)
154{
155 if (!ws)
156 return;
157
158 wakeup_source_drop(ws);
159 wakeup_source_record(ws);
160 kfree_const(ws->name);
161 kfree(ws);
162}
163EXPORT_SYMBOL_GPL(wakeup_source_destroy);
164
165/**
166 * wakeup_source_add - Add given object to the list of wakeup sources.
167 * @ws: Wakeup source object to add to the list.
168 */
169void wakeup_source_add(struct wakeup_source *ws)
170{
171 unsigned long flags;
172
173 if (WARN_ON(!ws))
174 return;
175
176 spin_lock_init(&ws->lock);
177 setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws);
178 ws->active = false;
179 ws->last_time = ktime_get();
180
181 spin_lock_irqsave(&events_lock, flags);
182 list_add_rcu(&ws->entry, &wakeup_sources);
183 spin_unlock_irqrestore(&events_lock, flags);
184}
185EXPORT_SYMBOL_GPL(wakeup_source_add);
186
187/**
188 * wakeup_source_remove - Remove given object from the wakeup sources list.
189 * @ws: Wakeup source object to remove from the list.
190 */
191void wakeup_source_remove(struct wakeup_source *ws)
192{
193 unsigned long flags;
194
195 if (WARN_ON(!ws))
196 return;
197
198 spin_lock_irqsave(&events_lock, flags);
199 list_del_rcu(&ws->entry);
200 spin_unlock_irqrestore(&events_lock, flags);
201 synchronize_rcu();
202}
203EXPORT_SYMBOL_GPL(wakeup_source_remove);
204
205/**
206 * wakeup_source_register - Create wakeup source and add it to the list.
207 * @name: Name of the wakeup source to register.
208 */
209struct wakeup_source *wakeup_source_register(const char *name)
210{
211 struct wakeup_source *ws;
212
213 ws = wakeup_source_create(name);
214 if (ws)
215 wakeup_source_add(ws);
216
217 return ws;
218}
219EXPORT_SYMBOL_GPL(wakeup_source_register);
220
221/**
222 * wakeup_source_unregister - Remove wakeup source from the list and remove it.
223 * @ws: Wakeup source object to unregister.
224 */
225void wakeup_source_unregister(struct wakeup_source *ws)
226{
227 if (ws) {
228 wakeup_source_remove(ws);
229 wakeup_source_destroy(ws);
230 }
231}
232EXPORT_SYMBOL_GPL(wakeup_source_unregister);
233
234/**
235 * device_wakeup_attach - Attach a wakeup source object to a device object.
236 * @dev: Device to handle.
237 * @ws: Wakeup source object to attach to @dev.
238 *
239 * This causes @dev to be treated as a wakeup device.
240 */
241static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
242{
243 spin_lock_irq(&dev->power.lock);
244 if (dev->power.wakeup) {
245 spin_unlock_irq(&dev->power.lock);
246 return -EEXIST;
247 }
248 dev->power.wakeup = ws;
249 if (dev->power.wakeirq)
250 device_wakeup_attach_irq(dev, dev->power.wakeirq);
251 spin_unlock_irq(&dev->power.lock);
252 return 0;
253}
254
255/**
256 * device_wakeup_enable - Enable given device to be a wakeup source.
257 * @dev: Device to handle.
258 *
259 * Create a wakeup source object, register it and attach it to @dev.
260 */
261int device_wakeup_enable(struct device *dev)
262{
263 struct wakeup_source *ws;
264 int ret;
265
266 if (!dev || !dev->power.can_wakeup)
267 return -EINVAL;
268
269 ws = wakeup_source_register(dev_name(dev));
270 if (!ws)
271 return -ENOMEM;
272
273 ret = device_wakeup_attach(dev, ws);
274 if (ret)
275 wakeup_source_unregister(ws);
276
277 return ret;
278}
279EXPORT_SYMBOL_GPL(device_wakeup_enable);
280
281/**
282 * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source
283 * @dev: Device to handle
284 * @wakeirq: Device specific wakeirq entry
285 *
286 * Attach a device wakeirq to the wakeup source so the device
287 * wake IRQ can be configured automatically for suspend and
288 * resume.
289 *
290 * Call under the device's power.lock lock.
291 */
292int device_wakeup_attach_irq(struct device *dev,
293 struct wake_irq *wakeirq)
294{
295 struct wakeup_source *ws;
296
297 ws = dev->power.wakeup;
298 if (!ws) {
299 dev_err(dev, "forgot to call call device_init_wakeup?\n");
300 return -EINVAL;
301 }
302
303 if (ws->wakeirq)
304 return -EEXIST;
305
306 ws->wakeirq = wakeirq;
307 return 0;
308}
309
310/**
311 * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source
312 * @dev: Device to handle
313 *
314 * Removes a device wakeirq from the wakeup source.
315 *
316 * Call under the device's power.lock lock.
317 */
318void device_wakeup_detach_irq(struct device *dev)
319{
320 struct wakeup_source *ws;
321
322 ws = dev->power.wakeup;
323 if (ws)
324 ws->wakeirq = NULL;
325}
326
327/**
328 * device_wakeup_arm_wake_irqs(void)
329 *
330 * Itereates over the list of device wakeirqs to arm them.
331 */
332void device_wakeup_arm_wake_irqs(void)
333{
334 struct wakeup_source *ws;
335
336 rcu_read_lock();
337 list_for_each_entry_rcu(ws, &wakeup_sources, entry)
338 dev_pm_arm_wake_irq(ws->wakeirq);
339
340 rcu_read_unlock();
341}
342
343/**
344 * device_wakeup_disarm_wake_irqs(void)
345 *
346 * Itereates over the list of device wakeirqs to disarm them.
347 */
348void device_wakeup_disarm_wake_irqs(void)
349{
350 struct wakeup_source *ws;
351
352 rcu_read_lock();
353 list_for_each_entry_rcu(ws, &wakeup_sources, entry)
354 dev_pm_disarm_wake_irq(ws->wakeirq);
355
356 rcu_read_unlock();
357}
358
359/**
360 * device_wakeup_detach - Detach a device's wakeup source object from it.
361 * @dev: Device to detach the wakeup source object from.
362 *
363 * After it returns, @dev will not be treated as a wakeup device any more.
364 */
365static struct wakeup_source *device_wakeup_detach(struct device *dev)
366{
367 struct wakeup_source *ws;
368
369 spin_lock_irq(&dev->power.lock);
370 ws = dev->power.wakeup;
371 dev->power.wakeup = NULL;
372 spin_unlock_irq(&dev->power.lock);
373 return ws;
374}
375
376/**
377 * device_wakeup_disable - Do not regard a device as a wakeup source any more.
378 * @dev: Device to handle.
379 *
380 * Detach the @dev's wakeup source object from it, unregister this wakeup source
381 * object and destroy it.
382 */
383int device_wakeup_disable(struct device *dev)
384{
385 struct wakeup_source *ws;
386
387 if (!dev || !dev->power.can_wakeup)
388 return -EINVAL;
389
390 ws = device_wakeup_detach(dev);
391 wakeup_source_unregister(ws);
392 return 0;
393}
394EXPORT_SYMBOL_GPL(device_wakeup_disable);
395
396/**
397 * device_set_wakeup_capable - Set/reset device wakeup capability flag.
398 * @dev: Device to handle.
399 * @capable: Whether or not @dev is capable of waking up the system from sleep.
400 *
401 * If @capable is set, set the @dev's power.can_wakeup flag and add its
402 * wakeup-related attributes to sysfs. Otherwise, unset the @dev's
403 * power.can_wakeup flag and remove its wakeup-related attributes from sysfs.
404 *
405 * This function may sleep and it can't be called from any context where
406 * sleeping is not allowed.
407 */
408void device_set_wakeup_capable(struct device *dev, bool capable)
409{
410 if (!!dev->power.can_wakeup == !!capable)
411 return;
412
413 if (device_is_registered(dev) && !list_empty(&dev->power.entry)) {
414 if (capable) {
415 if (wakeup_sysfs_add(dev))
416 return;
417 } else {
418 wakeup_sysfs_remove(dev);
419 }
420 }
421 dev->power.can_wakeup = capable;
422}
423EXPORT_SYMBOL_GPL(device_set_wakeup_capable);
424
425/**
426 * device_init_wakeup - Device wakeup initialization.
427 * @dev: Device to handle.
428 * @enable: Whether or not to enable @dev as a wakeup device.
429 *
430 * By default, most devices should leave wakeup disabled. The exceptions are
431 * devices that everyone expects to be wakeup sources: keyboards, power buttons,
432 * possibly network interfaces, etc. Also, devices that don't generate their
433 * own wakeup requests but merely forward requests from one bus to another
434 * (like PCI bridges) should have wakeup enabled by default.
435 */
436int device_init_wakeup(struct device *dev, bool enable)
437{
438 int ret = 0;
439
440 if (!dev)
441 return -EINVAL;
442
443 if (enable) {
444 device_set_wakeup_capable(dev, true);
445 ret = device_wakeup_enable(dev);
446 } else {
447 if (dev->power.can_wakeup)
448 device_wakeup_disable(dev);
449
450 device_set_wakeup_capable(dev, false);
451 }
452
453 return ret;
454}
455EXPORT_SYMBOL_GPL(device_init_wakeup);
456
457/**
458 * device_set_wakeup_enable - Enable or disable a device to wake up the system.
459 * @dev: Device to handle.
460 */
461int device_set_wakeup_enable(struct device *dev, bool enable)
462{
463 if (!dev || !dev->power.can_wakeup)
464 return -EINVAL;
465
466 return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev);
467}
468EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
469
470/**
471 * wakeup_source_not_registered - validate the given wakeup source.
472 * @ws: Wakeup source to be validated.
473 */
474static bool wakeup_source_not_registered(struct wakeup_source *ws)
475{
476 /*
477 * Use timer struct to check if the given source is initialized
478 * by wakeup_source_add.
479 */
480 return ws->timer.function != pm_wakeup_timer_fn ||
481 ws->timer.data != (unsigned long)ws;
482}
483
484/*
485 * The functions below use the observation that each wakeup event starts a
486 * period in which the system should not be suspended. The moment this period
487 * will end depends on how the wakeup event is going to be processed after being
488 * detected and all of the possible cases can be divided into two distinct
489 * groups.
490 *
491 * First, a wakeup event may be detected by the same functional unit that will
492 * carry out the entire processing of it and possibly will pass it to user space
493 * for further processing. In that case the functional unit that has detected
494 * the event may later "close" the "no suspend" period associated with it
495 * directly as soon as it has been dealt with. The pair of pm_stay_awake() and
496 * pm_relax(), balanced with each other, is supposed to be used in such
497 * situations.
498 *
499 * Second, a wakeup event may be detected by one functional unit and processed
500 * by another one. In that case the unit that has detected it cannot really
501 * "close" the "no suspend" period associated with it, unless it knows in
502 * advance what's going to happen to the event during processing. This
503 * knowledge, however, may not be available to it, so it can simply specify time
504 * to wait before the system can be suspended and pass it as the second
505 * argument of pm_wakeup_event().
506 *
507 * It is valid to call pm_relax() after pm_wakeup_event(), in which case the
508 * "no suspend" period will be ended either by the pm_relax(), or by the timer
509 * function executed when the timer expires, whichever comes first.
510 */
511
512/**
513 * wakup_source_activate - Mark given wakeup source as active.
514 * @ws: Wakeup source to handle.
515 *
516 * Update the @ws' statistics and, if @ws has just been activated, notify the PM
517 * core of the event by incrementing the counter of of wakeup events being
518 * processed.
519 */
520static void wakeup_source_activate(struct wakeup_source *ws)
521{
522 unsigned int cec;
523
524 if (WARN_ONCE(wakeup_source_not_registered(ws),
525 "unregistered wakeup source\n"))
526 return;
527
528 /*
529 * active wakeup source should bring the system
530 * out of PM_SUSPEND_FREEZE state
531 */
532 freeze_wake();
533
534 ws->active = true;
535 ws->active_count++;
536 ws->last_time = ktime_get();
537 if (ws->autosleep_enabled)
538 ws->start_prevent_time = ws->last_time;
539
540 /* Increment the counter of events in progress. */
541 cec = atomic_inc_return(&combined_event_count);
542
543 trace_wakeup_source_activate(ws->name, cec);
544}
545
546/**
547 * wakeup_source_report_event - Report wakeup event using the given source.
548 * @ws: Wakeup source to report the event for.
549 */
550static void wakeup_source_report_event(struct wakeup_source *ws)
551{
552 ws->event_count++;
553 /* This is racy, but the counter is approximate anyway. */
554 if (events_check_enabled)
555 ws->wakeup_count++;
556
557 if (!ws->active)
558 wakeup_source_activate(ws);
559}
560
561/**
562 * __pm_stay_awake - Notify the PM core of a wakeup event.
563 * @ws: Wakeup source object associated with the source of the event.
564 *
565 * It is safe to call this function from interrupt context.
566 */
567void __pm_stay_awake(struct wakeup_source *ws)
568{
569 unsigned long flags;
570
571 if (!ws)
572 return;
573
574 spin_lock_irqsave(&ws->lock, flags);
575
576 wakeup_source_report_event(ws);
577 del_timer(&ws->timer);
578 ws->timer_expires = 0;
579
580 spin_unlock_irqrestore(&ws->lock, flags);
581}
582EXPORT_SYMBOL_GPL(__pm_stay_awake);
583
584/**
585 * pm_stay_awake - Notify the PM core that a wakeup event is being processed.
586 * @dev: Device the wakeup event is related to.
587 *
588 * Notify the PM core of a wakeup event (signaled by @dev) by calling
589 * __pm_stay_awake for the @dev's wakeup source object.
590 *
591 * Call this function after detecting of a wakeup event if pm_relax() is going
592 * to be called directly after processing the event (and possibly passing it to
593 * user space for further processing).
594 */
595void pm_stay_awake(struct device *dev)
596{
597 unsigned long flags;
598
599 if (!dev)
600 return;
601
602 spin_lock_irqsave(&dev->power.lock, flags);
603 __pm_stay_awake(dev->power.wakeup);
604 spin_unlock_irqrestore(&dev->power.lock, flags);
605}
606EXPORT_SYMBOL_GPL(pm_stay_awake);
607
608#ifdef CONFIG_PM_AUTOSLEEP
609static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now)
610{
611 ktime_t delta = ktime_sub(now, ws->start_prevent_time);
612 ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta);
613}
614#else
615static inline void update_prevent_sleep_time(struct wakeup_source *ws,
616 ktime_t now) {}
617#endif
618
619/**
620 * wakup_source_deactivate - Mark given wakeup source as inactive.
621 * @ws: Wakeup source to handle.
622 *
623 * Update the @ws' statistics and notify the PM core that the wakeup source has
624 * become inactive by decrementing the counter of wakeup events being processed
625 * and incrementing the counter of registered wakeup events.
626 */
627static void wakeup_source_deactivate(struct wakeup_source *ws)
628{
629 unsigned int cnt, inpr, cec;
630 ktime_t duration;
631 ktime_t now;
632
633 ws->relax_count++;
634 /*
635 * __pm_relax() may be called directly or from a timer function.
636 * If it is called directly right after the timer function has been
637 * started, but before the timer function calls __pm_relax(), it is
638 * possible that __pm_stay_awake() will be called in the meantime and
639 * will set ws->active. Then, ws->active may be cleared immediately
640 * by the __pm_relax() called from the timer function, but in such a
641 * case ws->relax_count will be different from ws->active_count.
642 */
643 if (ws->relax_count != ws->active_count) {
644 ws->relax_count--;
645 return;
646 }
647
648 ws->active = false;
649
650 now = ktime_get();
651 duration = ktime_sub(now, ws->last_time);
652 ws->total_time = ktime_add(ws->total_time, duration);
653 if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
654 ws->max_time = duration;
655
656 ws->last_time = now;
657 del_timer(&ws->timer);
658 ws->timer_expires = 0;
659
660 if (ws->autosleep_enabled)
661 update_prevent_sleep_time(ws, now);
662
663 /*
664 * Increment the counter of registered wakeup events and decrement the
665 * couter of wakeup events in progress simultaneously.
666 */
667 cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count);
668 trace_wakeup_source_deactivate(ws->name, cec);
669
670 split_counters(&cnt, &inpr);
671 if (!inpr && waitqueue_active(&wakeup_count_wait_queue))
672 wake_up(&wakeup_count_wait_queue);
673}
674
675/**
676 * __pm_relax - Notify the PM core that processing of a wakeup event has ended.
677 * @ws: Wakeup source object associated with the source of the event.
678 *
679 * Call this function for wakeup events whose processing started with calling
680 * __pm_stay_awake().
681 *
682 * It is safe to call it from interrupt context.
683 */
684void __pm_relax(struct wakeup_source *ws)
685{
686 unsigned long flags;
687
688 if (!ws)
689 return;
690
691 spin_lock_irqsave(&ws->lock, flags);
692 if (ws->active)
693 wakeup_source_deactivate(ws);
694 spin_unlock_irqrestore(&ws->lock, flags);
695}
696EXPORT_SYMBOL_GPL(__pm_relax);
697
698/**
699 * pm_relax - Notify the PM core that processing of a wakeup event has ended.
700 * @dev: Device that signaled the event.
701 *
702 * Execute __pm_relax() for the @dev's wakeup source object.
703 */
704void pm_relax(struct device *dev)
705{
706 unsigned long flags;
707
708 if (!dev)
709 return;
710
711 spin_lock_irqsave(&dev->power.lock, flags);
712 __pm_relax(dev->power.wakeup);
713 spin_unlock_irqrestore(&dev->power.lock, flags);
714}
715EXPORT_SYMBOL_GPL(pm_relax);
716
717/**
718 * pm_wakeup_timer_fn - Delayed finalization of a wakeup event.
719 * @data: Address of the wakeup source object associated with the event source.
720 *
721 * Call wakeup_source_deactivate() for the wakeup source whose address is stored
722 * in @data if it is currently active and its timer has not been canceled and
723 * the expiration time of the timer is not in future.
724 */
725static void pm_wakeup_timer_fn(unsigned long data)
726{
727 struct wakeup_source *ws = (struct wakeup_source *)data;
728 unsigned long flags;
729
730 spin_lock_irqsave(&ws->lock, flags);
731
732 if (ws->active && ws->timer_expires
733 && time_after_eq(jiffies, ws->timer_expires)) {
734 wakeup_source_deactivate(ws);
735 ws->expire_count++;
736 }
737
738 spin_unlock_irqrestore(&ws->lock, flags);
739}
740
741/**
742 * __pm_wakeup_event - Notify the PM core of a wakeup event.
743 * @ws: Wakeup source object associated with the event source.
744 * @msec: Anticipated event processing time (in milliseconds).
745 *
746 * Notify the PM core of a wakeup event whose source is @ws that will take
747 * approximately @msec milliseconds to be processed by the kernel. If @ws is
748 * not active, activate it. If @msec is nonzero, set up the @ws' timer to
749 * execute pm_wakeup_timer_fn() in future.
750 *
751 * It is safe to call this function from interrupt context.
752 */
753void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec)
754{
755 unsigned long flags;
756 unsigned long expires;
757
758 if (!ws)
759 return;
760
761 spin_lock_irqsave(&ws->lock, flags);
762
763 wakeup_source_report_event(ws);
764
765 if (!msec) {
766 wakeup_source_deactivate(ws);
767 goto unlock;
768 }
769
770 expires = jiffies + msecs_to_jiffies(msec);
771 if (!expires)
772 expires = 1;
773
774 if (!ws->timer_expires || time_after(expires, ws->timer_expires)) {
775 mod_timer(&ws->timer, expires);
776 ws->timer_expires = expires;
777 }
778
779 unlock:
780 spin_unlock_irqrestore(&ws->lock, flags);
781}
782EXPORT_SYMBOL_GPL(__pm_wakeup_event);
783
784
785/**
786 * pm_wakeup_event - Notify the PM core of a wakeup event.
787 * @dev: Device the wakeup event is related to.
788 * @msec: Anticipated event processing time (in milliseconds).
789 *
790 * Call __pm_wakeup_event() for the @dev's wakeup source object.
791 */
792void pm_wakeup_event(struct device *dev, unsigned int msec)
793{
794 unsigned long flags;
795
796 if (!dev)
797 return;
798
799 spin_lock_irqsave(&dev->power.lock, flags);
800 __pm_wakeup_event(dev->power.wakeup, msec);
801 spin_unlock_irqrestore(&dev->power.lock, flags);
802}
803EXPORT_SYMBOL_GPL(pm_wakeup_event);
804
805void pm_print_active_wakeup_sources(void)
806{
807 struct wakeup_source *ws;
808 int active = 0;
809 struct wakeup_source *last_activity_ws = NULL;
810
811 rcu_read_lock();
812 list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
813 if (ws->active) {
814 pr_debug("active wakeup source: %s\n", ws->name);
815 active = 1;
816 } else if (!active &&
817 (!last_activity_ws ||
818 ktime_to_ns(ws->last_time) >
819 ktime_to_ns(last_activity_ws->last_time))) {
820 last_activity_ws = ws;
821 }
822 }
823
824 if (!active && last_activity_ws)
825 pr_debug("last active wakeup source: %s\n",
826 last_activity_ws->name);
827 rcu_read_unlock();
828}
829EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources);
830
831/**
832 * pm_wakeup_pending - Check if power transition in progress should be aborted.
833 *
834 * Compare the current number of registered wakeup events with its preserved
835 * value from the past and return true if new wakeup events have been registered
836 * since the old value was stored. Also return true if the current number of
837 * wakeup events being processed is different from zero.
838 */
839bool pm_wakeup_pending(void)
840{
841 unsigned long flags;
842 bool ret = false;
843
844 spin_lock_irqsave(&events_lock, flags);
845 if (events_check_enabled) {
846 unsigned int cnt, inpr;
847
848 split_counters(&cnt, &inpr);
849 ret = (cnt != saved_count || inpr > 0);
850 events_check_enabled = !ret;
851 }
852 spin_unlock_irqrestore(&events_lock, flags);
853
854 if (ret) {
855 pr_info("PM: Wakeup pending, aborting suspend\n");
856 pm_print_active_wakeup_sources();
857 }
858
859 return ret || pm_abort_suspend;
860}
861
862void pm_system_wakeup(void)
863{
864 pm_abort_suspend = true;
865 freeze_wake();
866}
867EXPORT_SYMBOL_GPL(pm_system_wakeup);
868
869void pm_wakeup_clear(void)
870{
871 pm_abort_suspend = false;
872 pm_wakeup_irq = 0;
873}
874
875void pm_system_irq_wakeup(unsigned int irq_number)
876{
877 if (pm_wakeup_irq == 0) {
878 pm_wakeup_irq = irq_number;
879 pm_system_wakeup();
880 }
881}
882
883/**
884 * pm_get_wakeup_count - Read the number of registered wakeup events.
885 * @count: Address to store the value at.
886 * @block: Whether or not to block.
887 *
888 * Store the number of registered wakeup events at the address in @count. If
889 * @block is set, block until the current number of wakeup events being
890 * processed is zero.
891 *
892 * Return 'false' if the current number of wakeup events being processed is
893 * nonzero. Otherwise return 'true'.
894 */
895bool pm_get_wakeup_count(unsigned int *count, bool block)
896{
897 unsigned int cnt, inpr;
898
899 if (block) {
900 DEFINE_WAIT(wait);
901
902 for (;;) {
903 prepare_to_wait(&wakeup_count_wait_queue, &wait,
904 TASK_INTERRUPTIBLE);
905 split_counters(&cnt, &inpr);
906 if (inpr == 0 || signal_pending(current))
907 break;
908 pm_print_active_wakeup_sources();
909 schedule();
910 }
911 finish_wait(&wakeup_count_wait_queue, &wait);
912 }
913
914 split_counters(&cnt, &inpr);
915 *count = cnt;
916 return !inpr;
917}
918
919/**
920 * pm_save_wakeup_count - Save the current number of registered wakeup events.
921 * @count: Value to compare with the current number of registered wakeup events.
922 *
923 * If @count is equal to the current number of registered wakeup events and the
924 * current number of wakeup events being processed is zero, store @count as the
925 * old number of registered wakeup events for pm_check_wakeup_events(), enable
926 * wakeup events detection and return 'true'. Otherwise disable wakeup events
927 * detection and return 'false'.
928 */
929bool pm_save_wakeup_count(unsigned int count)
930{
931 unsigned int cnt, inpr;
932 unsigned long flags;
933
934 events_check_enabled = false;
935 spin_lock_irqsave(&events_lock, flags);
936 split_counters(&cnt, &inpr);
937 if (cnt == count && inpr == 0) {
938 saved_count = count;
939 events_check_enabled = true;
940 }
941 spin_unlock_irqrestore(&events_lock, flags);
942 return events_check_enabled;
943}
944
945#ifdef CONFIG_PM_AUTOSLEEP
946/**
947 * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources.
948 * @enabled: Whether to set or to clear the autosleep_enabled flags.
949 */
950void pm_wakep_autosleep_enabled(bool set)
951{
952 struct wakeup_source *ws;
953 ktime_t now = ktime_get();
954
955 rcu_read_lock();
956 list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
957 spin_lock_irq(&ws->lock);
958 if (ws->autosleep_enabled != set) {
959 ws->autosleep_enabled = set;
960 if (ws->active) {
961 if (set)
962 ws->start_prevent_time = now;
963 else
964 update_prevent_sleep_time(ws, now);
965 }
966 }
967 spin_unlock_irq(&ws->lock);
968 }
969 rcu_read_unlock();
970}
971#endif /* CONFIG_PM_AUTOSLEEP */
972
973static struct dentry *wakeup_sources_stats_dentry;
974
975/**
976 * print_wakeup_source_stats - Print wakeup source statistics information.
977 * @m: seq_file to print the statistics into.
978 * @ws: Wakeup source object to print the statistics for.
979 */
980static int print_wakeup_source_stats(struct seq_file *m,
981 struct wakeup_source *ws)
982{
983 unsigned long flags;
984 ktime_t total_time;
985 ktime_t max_time;
986 unsigned long active_count;
987 ktime_t active_time;
988 ktime_t prevent_sleep_time;
989
990 spin_lock_irqsave(&ws->lock, flags);
991
992 total_time = ws->total_time;
993 max_time = ws->max_time;
994 prevent_sleep_time = ws->prevent_sleep_time;
995 active_count = ws->active_count;
996 if (ws->active) {
997 ktime_t now = ktime_get();
998
999 active_time = ktime_sub(now, ws->last_time);
1000 total_time = ktime_add(total_time, active_time);
1001 if (active_time > max_time)
1002 max_time = active_time;
1003
1004 if (ws->autosleep_enabled)
1005 prevent_sleep_time = ktime_add(prevent_sleep_time,
1006 ktime_sub(now, ws->start_prevent_time));
1007 } else {
1008 active_time = 0;
1009 }
1010
1011 seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n",
1012 ws->name, active_count, ws->event_count,
1013 ws->wakeup_count, ws->expire_count,
1014 ktime_to_ms(active_time), ktime_to_ms(total_time),
1015 ktime_to_ms(max_time), ktime_to_ms(ws->last_time),
1016 ktime_to_ms(prevent_sleep_time));
1017
1018 spin_unlock_irqrestore(&ws->lock, flags);
1019
1020 return 0;
1021}
1022
1023/**
1024 * wakeup_sources_stats_show - Print wakeup sources statistics information.
1025 * @m: seq_file to print the statistics into.
1026 */
1027static int wakeup_sources_stats_show(struct seq_file *m, void *unused)
1028{
1029 struct wakeup_source *ws;
1030
1031 seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"
1032 "expire_count\tactive_since\ttotal_time\tmax_time\t"
1033 "last_change\tprevent_suspend_time\n");
1034
1035 rcu_read_lock();
1036 list_for_each_entry_rcu(ws, &wakeup_sources, entry)
1037 print_wakeup_source_stats(m, ws);
1038 rcu_read_unlock();
1039
1040 print_wakeup_source_stats(m, &deleted_ws);
1041
1042 return 0;
1043}
1044
1045static int wakeup_sources_stats_open(struct inode *inode, struct file *file)
1046{
1047 return single_open(file, wakeup_sources_stats_show, NULL);
1048}
1049
1050static const struct file_operations wakeup_sources_stats_fops = {
1051 .owner = THIS_MODULE,
1052 .open = wakeup_sources_stats_open,
1053 .read = seq_read,
1054 .llseek = seq_lseek,
1055 .release = single_release,
1056};
1057
1058static int __init wakeup_sources_debugfs_init(void)
1059{
1060 wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources",
1061 S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops);
1062 return 0;
1063}
1064
1065postcore_initcall(wakeup_sources_debugfs_init);