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