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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#ifndef CONFIG_SUSPEND
23suspend_state_t pm_suspend_target_state;
24#define pm_suspend_target_state (PM_SUSPEND_ON)
25#endif
26
27#define list_for_each_entry_rcu_locked(pos, head, member) \
28 list_for_each_entry_rcu(pos, head, member, \
29 srcu_read_lock_held(&wakeup_srcu))
30/*
31 * If set, the suspend/hibernate code will abort transitions to a sleep state
32 * if wakeup events are registered during or immediately before the transition.
33 */
34bool events_check_enabled __read_mostly;
35
36/* First wakeup IRQ seen by the kernel in the last cycle. */
37unsigned int pm_wakeup_irq __read_mostly;
38
39/* If greater than 0 and the system is suspending, terminate the suspend. */
40static atomic_t pm_abort_suspend __read_mostly;
41
42/*
43 * Combined counters of registered wakeup events and wakeup events in progress.
44 * They need to be modified together atomically, so it's better to use one
45 * atomic variable to hold them both.
46 */
47static atomic_t combined_event_count = ATOMIC_INIT(0);
48
49#define IN_PROGRESS_BITS (sizeof(int) * 4)
50#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1)
51
52static void split_counters(unsigned int *cnt, unsigned int *inpr)
53{
54 unsigned int comb = atomic_read(&combined_event_count);
55
56 *cnt = (comb >> IN_PROGRESS_BITS);
57 *inpr = comb & MAX_IN_PROGRESS;
58}
59
60/* A preserved old value of the events counter. */
61static unsigned int saved_count;
62
63static DEFINE_RAW_SPINLOCK(events_lock);
64
65static void pm_wakeup_timer_fn(struct timer_list *t);
66
67static LIST_HEAD(wakeup_sources);
68
69static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
70
71DEFINE_STATIC_SRCU(wakeup_srcu);
72
73static struct wakeup_source deleted_ws = {
74 .name = "deleted",
75 .lock = __SPIN_LOCK_UNLOCKED(deleted_ws.lock),
76};
77
78static DEFINE_IDA(wakeup_ida);
79
80/**
81 * wakeup_source_create - Create a struct wakeup_source object.
82 * @name: Name of the new wakeup source.
83 */
84struct wakeup_source *wakeup_source_create(const char *name)
85{
86 struct wakeup_source *ws;
87 const char *ws_name;
88 int id;
89
90 ws = kzalloc(sizeof(*ws), GFP_KERNEL);
91 if (!ws)
92 goto err_ws;
93
94 ws_name = kstrdup_const(name, GFP_KERNEL);
95 if (!ws_name)
96 goto err_name;
97 ws->name = ws_name;
98
99 id = ida_alloc(&wakeup_ida, GFP_KERNEL);
100 if (id < 0)
101 goto err_id;
102 ws->id = id;
103
104 return ws;
105
106err_id:
107 kfree_const(ws->name);
108err_name:
109 kfree(ws);
110err_ws:
111 return NULL;
112}
113EXPORT_SYMBOL_GPL(wakeup_source_create);
114
115/*
116 * Record wakeup_source statistics being deleted into a dummy wakeup_source.
117 */
118static void wakeup_source_record(struct wakeup_source *ws)
119{
120 unsigned long flags;
121
122 spin_lock_irqsave(&deleted_ws.lock, flags);
123
124 if (ws->event_count) {
125 deleted_ws.total_time =
126 ktime_add(deleted_ws.total_time, ws->total_time);
127 deleted_ws.prevent_sleep_time =
128 ktime_add(deleted_ws.prevent_sleep_time,
129 ws->prevent_sleep_time);
130 deleted_ws.max_time =
131 ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ?
132 deleted_ws.max_time : ws->max_time;
133 deleted_ws.event_count += ws->event_count;
134 deleted_ws.active_count += ws->active_count;
135 deleted_ws.relax_count += ws->relax_count;
136 deleted_ws.expire_count += ws->expire_count;
137 deleted_ws.wakeup_count += ws->wakeup_count;
138 }
139
140 spin_unlock_irqrestore(&deleted_ws.lock, flags);
141}
142
143static void wakeup_source_free(struct wakeup_source *ws)
144{
145 ida_free(&wakeup_ida, ws->id);
146 kfree_const(ws->name);
147 kfree(ws);
148}
149
150/**
151 * wakeup_source_destroy - Destroy a struct wakeup_source object.
152 * @ws: Wakeup source to destroy.
153 *
154 * Use only for wakeup source objects created with wakeup_source_create().
155 */
156void wakeup_source_destroy(struct wakeup_source *ws)
157{
158 if (!ws)
159 return;
160
161 __pm_relax(ws);
162 wakeup_source_record(ws);
163 wakeup_source_free(ws);
164}
165EXPORT_SYMBOL_GPL(wakeup_source_destroy);
166
167/**
168 * wakeup_source_add - Add given object to the list of wakeup sources.
169 * @ws: Wakeup source object to add to the list.
170 */
171void wakeup_source_add(struct wakeup_source *ws)
172{
173 unsigned long flags;
174
175 if (WARN_ON(!ws))
176 return;
177
178 spin_lock_init(&ws->lock);
179 timer_setup(&ws->timer, pm_wakeup_timer_fn, 0);
180 ws->active = false;
181
182 raw_spin_lock_irqsave(&events_lock, flags);
183 list_add_rcu(&ws->entry, &wakeup_sources);
184 raw_spin_unlock_irqrestore(&events_lock, flags);
185}
186EXPORT_SYMBOL_GPL(wakeup_source_add);
187
188/**
189 * wakeup_source_remove - Remove given object from the wakeup sources list.
190 * @ws: Wakeup source object to remove from the list.
191 */
192void wakeup_source_remove(struct wakeup_source *ws)
193{
194 unsigned long flags;
195
196 if (WARN_ON(!ws))
197 return;
198
199 raw_spin_lock_irqsave(&events_lock, flags);
200 list_del_rcu(&ws->entry);
201 raw_spin_unlock_irqrestore(&events_lock, flags);
202 synchronize_srcu(&wakeup_srcu);
203
204 del_timer_sync(&ws->timer);
205 /*
206 * Clear timer.function to make wakeup_source_not_registered() treat
207 * this wakeup source as not registered.
208 */
209 ws->timer.function = NULL;
210}
211EXPORT_SYMBOL_GPL(wakeup_source_remove);
212
213/**
214 * wakeup_source_register - Create wakeup source and add it to the list.
215 * @dev: Device this wakeup source is associated with (or NULL if virtual).
216 * @name: Name of the wakeup source to register.
217 */
218struct wakeup_source *wakeup_source_register(struct device *dev,
219 const char *name)
220{
221 struct wakeup_source *ws;
222 int ret;
223
224 ws = wakeup_source_create(name);
225 if (ws) {
226 if (!dev || device_is_registered(dev)) {
227 ret = wakeup_source_sysfs_add(dev, ws);
228 if (ret) {
229 wakeup_source_free(ws);
230 return NULL;
231 }
232 }
233 wakeup_source_add(ws);
234 }
235 return ws;
236}
237EXPORT_SYMBOL_GPL(wakeup_source_register);
238
239/**
240 * wakeup_source_unregister - Remove wakeup source from the list and remove it.
241 * @ws: Wakeup source object to unregister.
242 */
243void wakeup_source_unregister(struct wakeup_source *ws)
244{
245 if (ws) {
246 wakeup_source_remove(ws);
247 if (ws->dev)
248 wakeup_source_sysfs_remove(ws);
249
250 wakeup_source_destroy(ws);
251 }
252}
253EXPORT_SYMBOL_GPL(wakeup_source_unregister);
254
255/**
256 * wakeup_sources_read_lock - Lock wakeup source list for read.
257 *
258 * Returns an index of srcu lock for struct wakeup_srcu.
259 * This index must be passed to the matching wakeup_sources_read_unlock().
260 */
261int wakeup_sources_read_lock(void)
262{
263 return srcu_read_lock(&wakeup_srcu);
264}
265EXPORT_SYMBOL_GPL(wakeup_sources_read_lock);
266
267/**
268 * wakeup_sources_read_unlock - Unlock wakeup source list.
269 * @idx: return value from corresponding wakeup_sources_read_lock()
270 */
271void wakeup_sources_read_unlock(int idx)
272{
273 srcu_read_unlock(&wakeup_srcu, idx);
274}
275EXPORT_SYMBOL_GPL(wakeup_sources_read_unlock);
276
277/**
278 * wakeup_sources_walk_start - Begin a walk on wakeup source list
279 *
280 * Returns first object of the list of wakeup sources.
281 *
282 * Note that to be safe, wakeup sources list needs to be locked by calling
283 * wakeup_source_read_lock() for this.
284 */
285struct wakeup_source *wakeup_sources_walk_start(void)
286{
287 struct list_head *ws_head = &wakeup_sources;
288
289 return list_entry_rcu(ws_head->next, struct wakeup_source, entry);
290}
291EXPORT_SYMBOL_GPL(wakeup_sources_walk_start);
292
293/**
294 * wakeup_sources_walk_next - Get next wakeup source from the list
295 * @ws: Previous wakeup source object
296 *
297 * Note that to be safe, wakeup sources list needs to be locked by calling
298 * wakeup_source_read_lock() for this.
299 */
300struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws)
301{
302 struct list_head *ws_head = &wakeup_sources;
303
304 return list_next_or_null_rcu(ws_head, &ws->entry,
305 struct wakeup_source, entry);
306}
307EXPORT_SYMBOL_GPL(wakeup_sources_walk_next);
308
309/**
310 * device_wakeup_attach - Attach a wakeup source object to a device object.
311 * @dev: Device to handle.
312 * @ws: Wakeup source object to attach to @dev.
313 *
314 * This causes @dev to be treated as a wakeup device.
315 */
316static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
317{
318 spin_lock_irq(&dev->power.lock);
319 if (dev->power.wakeup) {
320 spin_unlock_irq(&dev->power.lock);
321 return -EEXIST;
322 }
323 dev->power.wakeup = ws;
324 if (dev->power.wakeirq)
325 device_wakeup_attach_irq(dev, dev->power.wakeirq);
326 spin_unlock_irq(&dev->power.lock);
327 return 0;
328}
329
330/**
331 * device_wakeup_enable - Enable given device to be a wakeup source.
332 * @dev: Device to handle.
333 *
334 * Create a wakeup source object, register it and attach it to @dev.
335 */
336int device_wakeup_enable(struct device *dev)
337{
338 struct wakeup_source *ws;
339 int ret;
340
341 if (!dev || !dev->power.can_wakeup)
342 return -EINVAL;
343
344 if (pm_suspend_target_state != PM_SUSPEND_ON)
345 dev_dbg(dev, "Suspicious %s() during system transition!\n", __func__);
346
347 ws = wakeup_source_register(dev, dev_name(dev));
348 if (!ws)
349 return -ENOMEM;
350
351 ret = device_wakeup_attach(dev, ws);
352 if (ret)
353 wakeup_source_unregister(ws);
354
355 return ret;
356}
357EXPORT_SYMBOL_GPL(device_wakeup_enable);
358
359/**
360 * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source
361 * @dev: Device to handle
362 * @wakeirq: Device specific wakeirq entry
363 *
364 * Attach a device wakeirq to the wakeup source so the device
365 * wake IRQ can be configured automatically for suspend and
366 * resume.
367 *
368 * Call under the device's power.lock lock.
369 */
370void device_wakeup_attach_irq(struct device *dev,
371 struct wake_irq *wakeirq)
372{
373 struct wakeup_source *ws;
374
375 ws = dev->power.wakeup;
376 if (!ws)
377 return;
378
379 if (ws->wakeirq)
380 dev_err(dev, "Leftover wakeup IRQ found, overriding\n");
381
382 ws->wakeirq = wakeirq;
383}
384
385/**
386 * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source
387 * @dev: Device to handle
388 *
389 * Removes a device wakeirq from the wakeup source.
390 *
391 * Call under the device's power.lock lock.
392 */
393void device_wakeup_detach_irq(struct device *dev)
394{
395 struct wakeup_source *ws;
396
397 ws = dev->power.wakeup;
398 if (ws)
399 ws->wakeirq = NULL;
400}
401
402/**
403 * device_wakeup_arm_wake_irqs(void)
404 *
405 * Itereates over the list of device wakeirqs to arm them.
406 */
407void device_wakeup_arm_wake_irqs(void)
408{
409 struct wakeup_source *ws;
410 int srcuidx;
411
412 srcuidx = srcu_read_lock(&wakeup_srcu);
413 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry)
414 dev_pm_arm_wake_irq(ws->wakeirq);
415 srcu_read_unlock(&wakeup_srcu, srcuidx);
416}
417
418/**
419 * device_wakeup_disarm_wake_irqs(void)
420 *
421 * Itereates over the list of device wakeirqs to disarm them.
422 */
423void device_wakeup_disarm_wake_irqs(void)
424{
425 struct wakeup_source *ws;
426 int srcuidx;
427
428 srcuidx = srcu_read_lock(&wakeup_srcu);
429 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry)
430 dev_pm_disarm_wake_irq(ws->wakeirq);
431 srcu_read_unlock(&wakeup_srcu, srcuidx);
432}
433
434/**
435 * device_wakeup_detach - Detach a device's wakeup source object from it.
436 * @dev: Device to detach the wakeup source object from.
437 *
438 * After it returns, @dev will not be treated as a wakeup device any more.
439 */
440static struct wakeup_source *device_wakeup_detach(struct device *dev)
441{
442 struct wakeup_source *ws;
443
444 spin_lock_irq(&dev->power.lock);
445 ws = dev->power.wakeup;
446 dev->power.wakeup = NULL;
447 spin_unlock_irq(&dev->power.lock);
448 return ws;
449}
450
451/**
452 * device_wakeup_disable - Do not regard a device as a wakeup source any more.
453 * @dev: Device to handle.
454 *
455 * Detach the @dev's wakeup source object from it, unregister this wakeup source
456 * object and destroy it.
457 */
458int device_wakeup_disable(struct device *dev)
459{
460 struct wakeup_source *ws;
461
462 if (!dev || !dev->power.can_wakeup)
463 return -EINVAL;
464
465 ws = device_wakeup_detach(dev);
466 wakeup_source_unregister(ws);
467 return 0;
468}
469EXPORT_SYMBOL_GPL(device_wakeup_disable);
470
471/**
472 * device_set_wakeup_capable - Set/reset device wakeup capability flag.
473 * @dev: Device to handle.
474 * @capable: Whether or not @dev is capable of waking up the system from sleep.
475 *
476 * If @capable is set, set the @dev's power.can_wakeup flag and add its
477 * wakeup-related attributes to sysfs. Otherwise, unset the @dev's
478 * power.can_wakeup flag and remove its wakeup-related attributes from sysfs.
479 *
480 * This function may sleep and it can't be called from any context where
481 * sleeping is not allowed.
482 */
483void device_set_wakeup_capable(struct device *dev, bool capable)
484{
485 if (!!dev->power.can_wakeup == !!capable)
486 return;
487
488 dev->power.can_wakeup = capable;
489 if (device_is_registered(dev) && !list_empty(&dev->power.entry)) {
490 if (capable) {
491 int ret = wakeup_sysfs_add(dev);
492
493 if (ret)
494 dev_info(dev, "Wakeup sysfs attributes not added\n");
495 } else {
496 wakeup_sysfs_remove(dev);
497 }
498 }
499}
500EXPORT_SYMBOL_GPL(device_set_wakeup_capable);
501
502/**
503 * device_init_wakeup - Device wakeup initialization.
504 * @dev: Device to handle.
505 * @enable: Whether or not to enable @dev as a wakeup device.
506 *
507 * By default, most devices should leave wakeup disabled. The exceptions are
508 * devices that everyone expects to be wakeup sources: keyboards, power buttons,
509 * possibly network interfaces, etc. Also, devices that don't generate their
510 * own wakeup requests but merely forward requests from one bus to another
511 * (like PCI bridges) should have wakeup enabled by default.
512 */
513int device_init_wakeup(struct device *dev, bool enable)
514{
515 int ret = 0;
516
517 if (!dev)
518 return -EINVAL;
519
520 if (enable) {
521 device_set_wakeup_capable(dev, true);
522 ret = device_wakeup_enable(dev);
523 } else {
524 device_wakeup_disable(dev);
525 device_set_wakeup_capable(dev, false);
526 }
527
528 return ret;
529}
530EXPORT_SYMBOL_GPL(device_init_wakeup);
531
532/**
533 * device_set_wakeup_enable - Enable or disable a device to wake up the system.
534 * @dev: Device to handle.
535 */
536int device_set_wakeup_enable(struct device *dev, bool enable)
537{
538 return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev);
539}
540EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
541
542/**
543 * wakeup_source_not_registered - validate the given wakeup source.
544 * @ws: Wakeup source to be validated.
545 */
546static bool wakeup_source_not_registered(struct wakeup_source *ws)
547{
548 /*
549 * Use timer struct to check if the given source is initialized
550 * by wakeup_source_add.
551 */
552 return ws->timer.function != pm_wakeup_timer_fn;
553}
554
555/*
556 * The functions below use the observation that each wakeup event starts a
557 * period in which the system should not be suspended. The moment this period
558 * will end depends on how the wakeup event is going to be processed after being
559 * detected and all of the possible cases can be divided into two distinct
560 * groups.
561 *
562 * First, a wakeup event may be detected by the same functional unit that will
563 * carry out the entire processing of it and possibly will pass it to user space
564 * for further processing. In that case the functional unit that has detected
565 * the event may later "close" the "no suspend" period associated with it
566 * directly as soon as it has been dealt with. The pair of pm_stay_awake() and
567 * pm_relax(), balanced with each other, is supposed to be used in such
568 * situations.
569 *
570 * Second, a wakeup event may be detected by one functional unit and processed
571 * by another one. In that case the unit that has detected it cannot really
572 * "close" the "no suspend" period associated with it, unless it knows in
573 * advance what's going to happen to the event during processing. This
574 * knowledge, however, may not be available to it, so it can simply specify time
575 * to wait before the system can be suspended and pass it as the second
576 * argument of pm_wakeup_event().
577 *
578 * It is valid to call pm_relax() after pm_wakeup_event(), in which case the
579 * "no suspend" period will be ended either by the pm_relax(), or by the timer
580 * function executed when the timer expires, whichever comes first.
581 */
582
583/**
584 * wakup_source_activate - Mark given wakeup source as active.
585 * @ws: Wakeup source to handle.
586 *
587 * Update the @ws' statistics and, if @ws has just been activated, notify the PM
588 * core of the event by incrementing the counter of of wakeup events being
589 * processed.
590 */
591static void wakeup_source_activate(struct wakeup_source *ws)
592{
593 unsigned int cec;
594
595 if (WARN_ONCE(wakeup_source_not_registered(ws),
596 "unregistered wakeup source\n"))
597 return;
598
599 ws->active = true;
600 ws->active_count++;
601 ws->last_time = ktime_get();
602 if (ws->autosleep_enabled)
603 ws->start_prevent_time = ws->last_time;
604
605 /* Increment the counter of events in progress. */
606 cec = atomic_inc_return(&combined_event_count);
607
608 trace_wakeup_source_activate(ws->name, cec);
609}
610
611/**
612 * wakeup_source_report_event - Report wakeup event using the given source.
613 * @ws: Wakeup source to report the event for.
614 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
615 */
616static void wakeup_source_report_event(struct wakeup_source *ws, bool hard)
617{
618 ws->event_count++;
619 /* This is racy, but the counter is approximate anyway. */
620 if (events_check_enabled)
621 ws->wakeup_count++;
622
623 if (!ws->active)
624 wakeup_source_activate(ws);
625
626 if (hard)
627 pm_system_wakeup();
628}
629
630/**
631 * __pm_stay_awake - Notify the PM core of a wakeup event.
632 * @ws: Wakeup source object associated with the source of the event.
633 *
634 * It is safe to call this function from interrupt context.
635 */
636void __pm_stay_awake(struct wakeup_source *ws)
637{
638 unsigned long flags;
639
640 if (!ws)
641 return;
642
643 spin_lock_irqsave(&ws->lock, flags);
644
645 wakeup_source_report_event(ws, false);
646 del_timer(&ws->timer);
647 ws->timer_expires = 0;
648
649 spin_unlock_irqrestore(&ws->lock, flags);
650}
651EXPORT_SYMBOL_GPL(__pm_stay_awake);
652
653/**
654 * pm_stay_awake - Notify the PM core that a wakeup event is being processed.
655 * @dev: Device the wakeup event is related to.
656 *
657 * Notify the PM core of a wakeup event (signaled by @dev) by calling
658 * __pm_stay_awake for the @dev's wakeup source object.
659 *
660 * Call this function after detecting of a wakeup event if pm_relax() is going
661 * to be called directly after processing the event (and possibly passing it to
662 * user space for further processing).
663 */
664void pm_stay_awake(struct device *dev)
665{
666 unsigned long flags;
667
668 if (!dev)
669 return;
670
671 spin_lock_irqsave(&dev->power.lock, flags);
672 __pm_stay_awake(dev->power.wakeup);
673 spin_unlock_irqrestore(&dev->power.lock, flags);
674}
675EXPORT_SYMBOL_GPL(pm_stay_awake);
676
677#ifdef CONFIG_PM_AUTOSLEEP
678static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now)
679{
680 ktime_t delta = ktime_sub(now, ws->start_prevent_time);
681 ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta);
682}
683#else
684static inline void update_prevent_sleep_time(struct wakeup_source *ws,
685 ktime_t now) {}
686#endif
687
688/**
689 * wakup_source_deactivate - Mark given wakeup source as inactive.
690 * @ws: Wakeup source to handle.
691 *
692 * Update the @ws' statistics and notify the PM core that the wakeup source has
693 * become inactive by decrementing the counter of wakeup events being processed
694 * and incrementing the counter of registered wakeup events.
695 */
696static void wakeup_source_deactivate(struct wakeup_source *ws)
697{
698 unsigned int cnt, inpr, cec;
699 ktime_t duration;
700 ktime_t now;
701
702 ws->relax_count++;
703 /*
704 * __pm_relax() may be called directly or from a timer function.
705 * If it is called directly right after the timer function has been
706 * started, but before the timer function calls __pm_relax(), it is
707 * possible that __pm_stay_awake() will be called in the meantime and
708 * will set ws->active. Then, ws->active may be cleared immediately
709 * by the __pm_relax() called from the timer function, but in such a
710 * case ws->relax_count will be different from ws->active_count.
711 */
712 if (ws->relax_count != ws->active_count) {
713 ws->relax_count--;
714 return;
715 }
716
717 ws->active = false;
718
719 now = ktime_get();
720 duration = ktime_sub(now, ws->last_time);
721 ws->total_time = ktime_add(ws->total_time, duration);
722 if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
723 ws->max_time = duration;
724
725 ws->last_time = now;
726 del_timer(&ws->timer);
727 ws->timer_expires = 0;
728
729 if (ws->autosleep_enabled)
730 update_prevent_sleep_time(ws, now);
731
732 /*
733 * Increment the counter of registered wakeup events and decrement the
734 * couter of wakeup events in progress simultaneously.
735 */
736 cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count);
737 trace_wakeup_source_deactivate(ws->name, cec);
738
739 split_counters(&cnt, &inpr);
740 if (!inpr && waitqueue_active(&wakeup_count_wait_queue))
741 wake_up(&wakeup_count_wait_queue);
742}
743
744/**
745 * __pm_relax - Notify the PM core that processing of a wakeup event has ended.
746 * @ws: Wakeup source object associated with the source of the event.
747 *
748 * Call this function for wakeup events whose processing started with calling
749 * __pm_stay_awake().
750 *
751 * It is safe to call it from interrupt context.
752 */
753void __pm_relax(struct wakeup_source *ws)
754{
755 unsigned long flags;
756
757 if (!ws)
758 return;
759
760 spin_lock_irqsave(&ws->lock, flags);
761 if (ws->active)
762 wakeup_source_deactivate(ws);
763 spin_unlock_irqrestore(&ws->lock, flags);
764}
765EXPORT_SYMBOL_GPL(__pm_relax);
766
767/**
768 * pm_relax - Notify the PM core that processing of a wakeup event has ended.
769 * @dev: Device that signaled the event.
770 *
771 * Execute __pm_relax() for the @dev's wakeup source object.
772 */
773void pm_relax(struct device *dev)
774{
775 unsigned long flags;
776
777 if (!dev)
778 return;
779
780 spin_lock_irqsave(&dev->power.lock, flags);
781 __pm_relax(dev->power.wakeup);
782 spin_unlock_irqrestore(&dev->power.lock, flags);
783}
784EXPORT_SYMBOL_GPL(pm_relax);
785
786/**
787 * pm_wakeup_timer_fn - Delayed finalization of a wakeup event.
788 * @data: Address of the wakeup source object associated with the event source.
789 *
790 * Call wakeup_source_deactivate() for the wakeup source whose address is stored
791 * in @data if it is currently active and its timer has not been canceled and
792 * the expiration time of the timer is not in future.
793 */
794static void pm_wakeup_timer_fn(struct timer_list *t)
795{
796 struct wakeup_source *ws = from_timer(ws, t, timer);
797 unsigned long flags;
798
799 spin_lock_irqsave(&ws->lock, flags);
800
801 if (ws->active && ws->timer_expires
802 && time_after_eq(jiffies, ws->timer_expires)) {
803 wakeup_source_deactivate(ws);
804 ws->expire_count++;
805 }
806
807 spin_unlock_irqrestore(&ws->lock, flags);
808}
809
810/**
811 * pm_wakeup_ws_event - Notify the PM core of a wakeup event.
812 * @ws: Wakeup source object associated with the event source.
813 * @msec: Anticipated event processing time (in milliseconds).
814 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
815 *
816 * Notify the PM core of a wakeup event whose source is @ws that will take
817 * approximately @msec milliseconds to be processed by the kernel. If @ws is
818 * not active, activate it. If @msec is nonzero, set up the @ws' timer to
819 * execute pm_wakeup_timer_fn() in future.
820 *
821 * It is safe to call this function from interrupt context.
822 */
823void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard)
824{
825 unsigned long flags;
826 unsigned long expires;
827
828 if (!ws)
829 return;
830
831 spin_lock_irqsave(&ws->lock, flags);
832
833 wakeup_source_report_event(ws, hard);
834
835 if (!msec) {
836 wakeup_source_deactivate(ws);
837 goto unlock;
838 }
839
840 expires = jiffies + msecs_to_jiffies(msec);
841 if (!expires)
842 expires = 1;
843
844 if (!ws->timer_expires || time_after(expires, ws->timer_expires)) {
845 mod_timer(&ws->timer, expires);
846 ws->timer_expires = expires;
847 }
848
849 unlock:
850 spin_unlock_irqrestore(&ws->lock, flags);
851}
852EXPORT_SYMBOL_GPL(pm_wakeup_ws_event);
853
854/**
855 * pm_wakeup_dev_event - Notify the PM core of a wakeup event.
856 * @dev: Device the wakeup event is related to.
857 * @msec: Anticipated event processing time (in milliseconds).
858 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
859 *
860 * Call pm_wakeup_ws_event() for the @dev's wakeup source object.
861 */
862void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard)
863{
864 unsigned long flags;
865
866 if (!dev)
867 return;
868
869 spin_lock_irqsave(&dev->power.lock, flags);
870 pm_wakeup_ws_event(dev->power.wakeup, msec, hard);
871 spin_unlock_irqrestore(&dev->power.lock, flags);
872}
873EXPORT_SYMBOL_GPL(pm_wakeup_dev_event);
874
875void pm_print_active_wakeup_sources(void)
876{
877 struct wakeup_source *ws;
878 int srcuidx, active = 0;
879 struct wakeup_source *last_activity_ws = NULL;
880
881 srcuidx = srcu_read_lock(&wakeup_srcu);
882 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
883 if (ws->active) {
884 pm_pr_dbg("active wakeup source: %s\n", ws->name);
885 active = 1;
886 } else if (!active &&
887 (!last_activity_ws ||
888 ktime_to_ns(ws->last_time) >
889 ktime_to_ns(last_activity_ws->last_time))) {
890 last_activity_ws = ws;
891 }
892 }
893
894 if (!active && last_activity_ws)
895 pm_pr_dbg("last active wakeup source: %s\n",
896 last_activity_ws->name);
897 srcu_read_unlock(&wakeup_srcu, srcuidx);
898}
899EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources);
900
901/**
902 * pm_wakeup_pending - Check if power transition in progress should be aborted.
903 *
904 * Compare the current number of registered wakeup events with its preserved
905 * value from the past and return true if new wakeup events have been registered
906 * since the old value was stored. Also return true if the current number of
907 * wakeup events being processed is different from zero.
908 */
909bool pm_wakeup_pending(void)
910{
911 unsigned long flags;
912 bool ret = false;
913
914 raw_spin_lock_irqsave(&events_lock, flags);
915 if (events_check_enabled) {
916 unsigned int cnt, inpr;
917
918 split_counters(&cnt, &inpr);
919 ret = (cnt != saved_count || inpr > 0);
920 events_check_enabled = !ret;
921 }
922 raw_spin_unlock_irqrestore(&events_lock, flags);
923
924 if (ret) {
925 pm_pr_dbg("Wakeup pending, aborting suspend\n");
926 pm_print_active_wakeup_sources();
927 }
928
929 return ret || atomic_read(&pm_abort_suspend) > 0;
930}
931
932void pm_system_wakeup(void)
933{
934 atomic_inc(&pm_abort_suspend);
935 s2idle_wake();
936}
937EXPORT_SYMBOL_GPL(pm_system_wakeup);
938
939void pm_system_cancel_wakeup(void)
940{
941 atomic_dec_if_positive(&pm_abort_suspend);
942}
943
944void pm_wakeup_clear(bool reset)
945{
946 pm_wakeup_irq = 0;
947 if (reset)
948 atomic_set(&pm_abort_suspend, 0);
949}
950
951void pm_system_irq_wakeup(unsigned int irq_number)
952{
953 if (pm_wakeup_irq == 0) {
954 pm_wakeup_irq = irq_number;
955 pm_system_wakeup();
956 }
957}
958
959/**
960 * pm_get_wakeup_count - Read the number of registered wakeup events.
961 * @count: Address to store the value at.
962 * @block: Whether or not to block.
963 *
964 * Store the number of registered wakeup events at the address in @count. If
965 * @block is set, block until the current number of wakeup events being
966 * processed is zero.
967 *
968 * Return 'false' if the current number of wakeup events being processed is
969 * nonzero. Otherwise return 'true'.
970 */
971bool pm_get_wakeup_count(unsigned int *count, bool block)
972{
973 unsigned int cnt, inpr;
974
975 if (block) {
976 DEFINE_WAIT(wait);
977
978 for (;;) {
979 prepare_to_wait(&wakeup_count_wait_queue, &wait,
980 TASK_INTERRUPTIBLE);
981 split_counters(&cnt, &inpr);
982 if (inpr == 0 || signal_pending(current))
983 break;
984 pm_print_active_wakeup_sources();
985 schedule();
986 }
987 finish_wait(&wakeup_count_wait_queue, &wait);
988 }
989
990 split_counters(&cnt, &inpr);
991 *count = cnt;
992 return !inpr;
993}
994
995/**
996 * pm_save_wakeup_count - Save the current number of registered wakeup events.
997 * @count: Value to compare with the current number of registered wakeup events.
998 *
999 * If @count is equal to the current number of registered wakeup events and the
1000 * current number of wakeup events being processed is zero, store @count as the
1001 * old number of registered wakeup events for pm_check_wakeup_events(), enable
1002 * wakeup events detection and return 'true'. Otherwise disable wakeup events
1003 * detection and return 'false'.
1004 */
1005bool pm_save_wakeup_count(unsigned int count)
1006{
1007 unsigned int cnt, inpr;
1008 unsigned long flags;
1009
1010 events_check_enabled = false;
1011 raw_spin_lock_irqsave(&events_lock, flags);
1012 split_counters(&cnt, &inpr);
1013 if (cnt == count && inpr == 0) {
1014 saved_count = count;
1015 events_check_enabled = true;
1016 }
1017 raw_spin_unlock_irqrestore(&events_lock, flags);
1018 return events_check_enabled;
1019}
1020
1021#ifdef CONFIG_PM_AUTOSLEEP
1022/**
1023 * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources.
1024 * @enabled: Whether to set or to clear the autosleep_enabled flags.
1025 */
1026void pm_wakep_autosleep_enabled(bool set)
1027{
1028 struct wakeup_source *ws;
1029 ktime_t now = ktime_get();
1030 int srcuidx;
1031
1032 srcuidx = srcu_read_lock(&wakeup_srcu);
1033 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
1034 spin_lock_irq(&ws->lock);
1035 if (ws->autosleep_enabled != set) {
1036 ws->autosleep_enabled = set;
1037 if (ws->active) {
1038 if (set)
1039 ws->start_prevent_time = now;
1040 else
1041 update_prevent_sleep_time(ws, now);
1042 }
1043 }
1044 spin_unlock_irq(&ws->lock);
1045 }
1046 srcu_read_unlock(&wakeup_srcu, srcuidx);
1047}
1048#endif /* CONFIG_PM_AUTOSLEEP */
1049
1050/**
1051 * print_wakeup_source_stats - Print wakeup source statistics information.
1052 * @m: seq_file to print the statistics into.
1053 * @ws: Wakeup source object to print the statistics for.
1054 */
1055static int print_wakeup_source_stats(struct seq_file *m,
1056 struct wakeup_source *ws)
1057{
1058 unsigned long flags;
1059 ktime_t total_time;
1060 ktime_t max_time;
1061 unsigned long active_count;
1062 ktime_t active_time;
1063 ktime_t prevent_sleep_time;
1064
1065 spin_lock_irqsave(&ws->lock, flags);
1066
1067 total_time = ws->total_time;
1068 max_time = ws->max_time;
1069 prevent_sleep_time = ws->prevent_sleep_time;
1070 active_count = ws->active_count;
1071 if (ws->active) {
1072 ktime_t now = ktime_get();
1073
1074 active_time = ktime_sub(now, ws->last_time);
1075 total_time = ktime_add(total_time, active_time);
1076 if (active_time > max_time)
1077 max_time = active_time;
1078
1079 if (ws->autosleep_enabled)
1080 prevent_sleep_time = ktime_add(prevent_sleep_time,
1081 ktime_sub(now, ws->start_prevent_time));
1082 } else {
1083 active_time = 0;
1084 }
1085
1086 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",
1087 ws->name, active_count, ws->event_count,
1088 ws->wakeup_count, ws->expire_count,
1089 ktime_to_ms(active_time), ktime_to_ms(total_time),
1090 ktime_to_ms(max_time), ktime_to_ms(ws->last_time),
1091 ktime_to_ms(prevent_sleep_time));
1092
1093 spin_unlock_irqrestore(&ws->lock, flags);
1094
1095 return 0;
1096}
1097
1098static void *wakeup_sources_stats_seq_start(struct seq_file *m,
1099 loff_t *pos)
1100{
1101 struct wakeup_source *ws;
1102 loff_t n = *pos;
1103 int *srcuidx = m->private;
1104
1105 if (n == 0) {
1106 seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"
1107 "expire_count\tactive_since\ttotal_time\tmax_time\t"
1108 "last_change\tprevent_suspend_time\n");
1109 }
1110
1111 *srcuidx = srcu_read_lock(&wakeup_srcu);
1112 list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) {
1113 if (n-- <= 0)
1114 return ws;
1115 }
1116
1117 return NULL;
1118}
1119
1120static void *wakeup_sources_stats_seq_next(struct seq_file *m,
1121 void *v, loff_t *pos)
1122{
1123 struct wakeup_source *ws = v;
1124 struct wakeup_source *next_ws = NULL;
1125
1126 ++(*pos);
1127
1128 list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) {
1129 next_ws = ws;
1130 break;
1131 }
1132
1133 if (!next_ws)
1134 print_wakeup_source_stats(m, &deleted_ws);
1135
1136 return next_ws;
1137}
1138
1139static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v)
1140{
1141 int *srcuidx = m->private;
1142
1143 srcu_read_unlock(&wakeup_srcu, *srcuidx);
1144}
1145
1146/**
1147 * wakeup_sources_stats_seq_show - Print wakeup sources statistics information.
1148 * @m: seq_file to print the statistics into.
1149 * @v: wakeup_source of each iteration
1150 */
1151static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v)
1152{
1153 struct wakeup_source *ws = v;
1154
1155 print_wakeup_source_stats(m, ws);
1156
1157 return 0;
1158}
1159
1160static const struct seq_operations wakeup_sources_stats_seq_ops = {
1161 .start = wakeup_sources_stats_seq_start,
1162 .next = wakeup_sources_stats_seq_next,
1163 .stop = wakeup_sources_stats_seq_stop,
1164 .show = wakeup_sources_stats_seq_show,
1165};
1166
1167static int wakeup_sources_stats_open(struct inode *inode, struct file *file)
1168{
1169 return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int));
1170}
1171
1172static const struct file_operations wakeup_sources_stats_fops = {
1173 .owner = THIS_MODULE,
1174 .open = wakeup_sources_stats_open,
1175 .read = seq_read,
1176 .llseek = seq_lseek,
1177 .release = seq_release_private,
1178};
1179
1180static int __init wakeup_sources_debugfs_init(void)
1181{
1182 debugfs_create_file("wakeup_sources", S_IRUGO, NULL, NULL,
1183 &wakeup_sources_stats_fops);
1184 return 0;
1185}
1186
1187postcore_initcall(wakeup_sources_debugfs_init);
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#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_RAW_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
75static DEFINE_IDA(wakeup_ida);
76
77/**
78 * wakeup_source_create - Create a struct wakeup_source object.
79 * @name: Name of the new wakeup source.
80 */
81struct wakeup_source *wakeup_source_create(const char *name)
82{
83 struct wakeup_source *ws;
84 const char *ws_name;
85 int id;
86
87 ws = kzalloc(sizeof(*ws), GFP_KERNEL);
88 if (!ws)
89 goto err_ws;
90
91 ws_name = kstrdup_const(name, GFP_KERNEL);
92 if (!ws_name)
93 goto err_name;
94 ws->name = ws_name;
95
96 id = ida_alloc(&wakeup_ida, GFP_KERNEL);
97 if (id < 0)
98 goto err_id;
99 ws->id = id;
100
101 return ws;
102
103err_id:
104 kfree_const(ws->name);
105err_name:
106 kfree(ws);
107err_ws:
108 return NULL;
109}
110EXPORT_SYMBOL_GPL(wakeup_source_create);
111
112/*
113 * Record wakeup_source statistics being deleted into a dummy wakeup_source.
114 */
115static void wakeup_source_record(struct wakeup_source *ws)
116{
117 unsigned long flags;
118
119 spin_lock_irqsave(&deleted_ws.lock, flags);
120
121 if (ws->event_count) {
122 deleted_ws.total_time =
123 ktime_add(deleted_ws.total_time, ws->total_time);
124 deleted_ws.prevent_sleep_time =
125 ktime_add(deleted_ws.prevent_sleep_time,
126 ws->prevent_sleep_time);
127 deleted_ws.max_time =
128 ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ?
129 deleted_ws.max_time : ws->max_time;
130 deleted_ws.event_count += ws->event_count;
131 deleted_ws.active_count += ws->active_count;
132 deleted_ws.relax_count += ws->relax_count;
133 deleted_ws.expire_count += ws->expire_count;
134 deleted_ws.wakeup_count += ws->wakeup_count;
135 }
136
137 spin_unlock_irqrestore(&deleted_ws.lock, flags);
138}
139
140static void wakeup_source_free(struct wakeup_source *ws)
141{
142 ida_free(&wakeup_ida, ws->id);
143 kfree_const(ws->name);
144 kfree(ws);
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 __pm_relax(ws);
159 wakeup_source_record(ws);
160 wakeup_source_free(ws);
161}
162EXPORT_SYMBOL_GPL(wakeup_source_destroy);
163
164/**
165 * wakeup_source_add - Add given object to the list of wakeup sources.
166 * @ws: Wakeup source object to add to the list.
167 */
168void wakeup_source_add(struct wakeup_source *ws)
169{
170 unsigned long flags;
171
172 if (WARN_ON(!ws))
173 return;
174
175 spin_lock_init(&ws->lock);
176 timer_setup(&ws->timer, pm_wakeup_timer_fn, 0);
177 ws->active = false;
178
179 raw_spin_lock_irqsave(&events_lock, flags);
180 list_add_rcu(&ws->entry, &wakeup_sources);
181 raw_spin_unlock_irqrestore(&events_lock, flags);
182}
183EXPORT_SYMBOL_GPL(wakeup_source_add);
184
185/**
186 * wakeup_source_remove - Remove given object from the wakeup sources list.
187 * @ws: Wakeup source object to remove from the list.
188 */
189void wakeup_source_remove(struct wakeup_source *ws)
190{
191 unsigned long flags;
192
193 if (WARN_ON(!ws))
194 return;
195
196 raw_spin_lock_irqsave(&events_lock, flags);
197 list_del_rcu(&ws->entry);
198 raw_spin_unlock_irqrestore(&events_lock, flags);
199 synchronize_srcu(&wakeup_srcu);
200
201 del_timer_sync(&ws->timer);
202 /*
203 * Clear timer.function to make wakeup_source_not_registered() treat
204 * this wakeup source as not registered.
205 */
206 ws->timer.function = NULL;
207}
208EXPORT_SYMBOL_GPL(wakeup_source_remove);
209
210/**
211 * wakeup_source_register - Create wakeup source and add it to the list.
212 * @dev: Device this wakeup source is associated with (or NULL if virtual).
213 * @name: Name of the wakeup source to register.
214 */
215struct wakeup_source *wakeup_source_register(struct device *dev,
216 const char *name)
217{
218 struct wakeup_source *ws;
219 int ret;
220
221 ws = wakeup_source_create(name);
222 if (ws) {
223 if (!dev || device_is_registered(dev)) {
224 ret = wakeup_source_sysfs_add(dev, ws);
225 if (ret) {
226 wakeup_source_free(ws);
227 return NULL;
228 }
229 }
230 wakeup_source_add(ws);
231 }
232 return ws;
233}
234EXPORT_SYMBOL_GPL(wakeup_source_register);
235
236/**
237 * wakeup_source_unregister - Remove wakeup source from the list and remove it.
238 * @ws: Wakeup source object to unregister.
239 */
240void wakeup_source_unregister(struct wakeup_source *ws)
241{
242 if (ws) {
243 wakeup_source_remove(ws);
244 wakeup_source_sysfs_remove(ws);
245 wakeup_source_destroy(ws);
246 }
247}
248EXPORT_SYMBOL_GPL(wakeup_source_unregister);
249
250/**
251 * device_wakeup_attach - Attach a wakeup source object to a device object.
252 * @dev: Device to handle.
253 * @ws: Wakeup source object to attach to @dev.
254 *
255 * This causes @dev to be treated as a wakeup device.
256 */
257static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
258{
259 spin_lock_irq(&dev->power.lock);
260 if (dev->power.wakeup) {
261 spin_unlock_irq(&dev->power.lock);
262 return -EEXIST;
263 }
264 dev->power.wakeup = ws;
265 if (dev->power.wakeirq)
266 device_wakeup_attach_irq(dev, dev->power.wakeirq);
267 spin_unlock_irq(&dev->power.lock);
268 return 0;
269}
270
271/**
272 * device_wakeup_enable - Enable given device to be a wakeup source.
273 * @dev: Device to handle.
274 *
275 * Create a wakeup source object, register it and attach it to @dev.
276 */
277int device_wakeup_enable(struct device *dev)
278{
279 struct wakeup_source *ws;
280 int ret;
281
282 if (!dev || !dev->power.can_wakeup)
283 return -EINVAL;
284
285 if (pm_suspend_target_state != PM_SUSPEND_ON)
286 dev_dbg(dev, "Suspicious %s() during system transition!\n", __func__);
287
288 ws = wakeup_source_register(dev, dev_name(dev));
289 if (!ws)
290 return -ENOMEM;
291
292 ret = device_wakeup_attach(dev, ws);
293 if (ret)
294 wakeup_source_unregister(ws);
295
296 return ret;
297}
298EXPORT_SYMBOL_GPL(device_wakeup_enable);
299
300/**
301 * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source
302 * @dev: Device to handle
303 * @wakeirq: Device specific wakeirq entry
304 *
305 * Attach a device wakeirq to the wakeup source so the device
306 * wake IRQ can be configured automatically for suspend and
307 * resume.
308 *
309 * Call under the device's power.lock lock.
310 */
311void device_wakeup_attach_irq(struct device *dev,
312 struct wake_irq *wakeirq)
313{
314 struct wakeup_source *ws;
315
316 ws = dev->power.wakeup;
317 if (!ws)
318 return;
319
320 if (ws->wakeirq)
321 dev_err(dev, "Leftover wakeup IRQ found, overriding\n");
322
323 ws->wakeirq = wakeirq;
324}
325
326/**
327 * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source
328 * @dev: Device to handle
329 *
330 * Removes a device wakeirq from the wakeup source.
331 *
332 * Call under the device's power.lock lock.
333 */
334void device_wakeup_detach_irq(struct device *dev)
335{
336 struct wakeup_source *ws;
337
338 ws = dev->power.wakeup;
339 if (ws)
340 ws->wakeirq = NULL;
341}
342
343/**
344 * device_wakeup_arm_wake_irqs(void)
345 *
346 * Itereates over the list of device wakeirqs to arm them.
347 */
348void device_wakeup_arm_wake_irqs(void)
349{
350 struct wakeup_source *ws;
351 int srcuidx;
352
353 srcuidx = srcu_read_lock(&wakeup_srcu);
354 list_for_each_entry_rcu(ws, &wakeup_sources, entry)
355 dev_pm_arm_wake_irq(ws->wakeirq);
356 srcu_read_unlock(&wakeup_srcu, srcuidx);
357}
358
359/**
360 * device_wakeup_disarm_wake_irqs(void)
361 *
362 * Itereates over the list of device wakeirqs to disarm them.
363 */
364void device_wakeup_disarm_wake_irqs(void)
365{
366 struct wakeup_source *ws;
367 int srcuidx;
368
369 srcuidx = srcu_read_lock(&wakeup_srcu);
370 list_for_each_entry_rcu(ws, &wakeup_sources, entry)
371 dev_pm_disarm_wake_irq(ws->wakeirq);
372 srcu_read_unlock(&wakeup_srcu, srcuidx);
373}
374
375/**
376 * device_wakeup_detach - Detach a device's wakeup source object from it.
377 * @dev: Device to detach the wakeup source object from.
378 *
379 * After it returns, @dev will not be treated as a wakeup device any more.
380 */
381static struct wakeup_source *device_wakeup_detach(struct device *dev)
382{
383 struct wakeup_source *ws;
384
385 spin_lock_irq(&dev->power.lock);
386 ws = dev->power.wakeup;
387 dev->power.wakeup = NULL;
388 spin_unlock_irq(&dev->power.lock);
389 return ws;
390}
391
392/**
393 * device_wakeup_disable - Do not regard a device as a wakeup source any more.
394 * @dev: Device to handle.
395 *
396 * Detach the @dev's wakeup source object from it, unregister this wakeup source
397 * object and destroy it.
398 */
399int device_wakeup_disable(struct device *dev)
400{
401 struct wakeup_source *ws;
402
403 if (!dev || !dev->power.can_wakeup)
404 return -EINVAL;
405
406 ws = device_wakeup_detach(dev);
407 wakeup_source_unregister(ws);
408 return 0;
409}
410EXPORT_SYMBOL_GPL(device_wakeup_disable);
411
412/**
413 * device_set_wakeup_capable - Set/reset device wakeup capability flag.
414 * @dev: Device to handle.
415 * @capable: Whether or not @dev is capable of waking up the system from sleep.
416 *
417 * If @capable is set, set the @dev's power.can_wakeup flag and add its
418 * wakeup-related attributes to sysfs. Otherwise, unset the @dev's
419 * power.can_wakeup flag and remove its wakeup-related attributes from sysfs.
420 *
421 * This function may sleep and it can't be called from any context where
422 * sleeping is not allowed.
423 */
424void device_set_wakeup_capable(struct device *dev, bool capable)
425{
426 if (!!dev->power.can_wakeup == !!capable)
427 return;
428
429 dev->power.can_wakeup = capable;
430 if (device_is_registered(dev) && !list_empty(&dev->power.entry)) {
431 if (capable) {
432 int ret = wakeup_sysfs_add(dev);
433
434 if (ret)
435 dev_info(dev, "Wakeup sysfs attributes not added\n");
436 } else {
437 wakeup_sysfs_remove(dev);
438 }
439 }
440}
441EXPORT_SYMBOL_GPL(device_set_wakeup_capable);
442
443/**
444 * device_init_wakeup - Device wakeup initialization.
445 * @dev: Device to handle.
446 * @enable: Whether or not to enable @dev as a wakeup device.
447 *
448 * By default, most devices should leave wakeup disabled. The exceptions are
449 * devices that everyone expects to be wakeup sources: keyboards, power buttons,
450 * possibly network interfaces, etc. Also, devices that don't generate their
451 * own wakeup requests but merely forward requests from one bus to another
452 * (like PCI bridges) should have wakeup enabled by default.
453 */
454int device_init_wakeup(struct device *dev, bool enable)
455{
456 int ret = 0;
457
458 if (!dev)
459 return -EINVAL;
460
461 if (enable) {
462 device_set_wakeup_capable(dev, true);
463 ret = device_wakeup_enable(dev);
464 } else {
465 device_wakeup_disable(dev);
466 device_set_wakeup_capable(dev, false);
467 }
468
469 return ret;
470}
471EXPORT_SYMBOL_GPL(device_init_wakeup);
472
473/**
474 * device_set_wakeup_enable - Enable or disable a device to wake up the system.
475 * @dev: Device to handle.
476 */
477int device_set_wakeup_enable(struct device *dev, bool enable)
478{
479 return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev);
480}
481EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
482
483/**
484 * wakeup_source_not_registered - validate the given wakeup source.
485 * @ws: Wakeup source to be validated.
486 */
487static bool wakeup_source_not_registered(struct wakeup_source *ws)
488{
489 /*
490 * Use timer struct to check if the given source is initialized
491 * by wakeup_source_add.
492 */
493 return ws->timer.function != pm_wakeup_timer_fn;
494}
495
496/*
497 * The functions below use the observation that each wakeup event starts a
498 * period in which the system should not be suspended. The moment this period
499 * will end depends on how the wakeup event is going to be processed after being
500 * detected and all of the possible cases can be divided into two distinct
501 * groups.
502 *
503 * First, a wakeup event may be detected by the same functional unit that will
504 * carry out the entire processing of it and possibly will pass it to user space
505 * for further processing. In that case the functional unit that has detected
506 * the event may later "close" the "no suspend" period associated with it
507 * directly as soon as it has been dealt with. The pair of pm_stay_awake() and
508 * pm_relax(), balanced with each other, is supposed to be used in such
509 * situations.
510 *
511 * Second, a wakeup event may be detected by one functional unit and processed
512 * by another one. In that case the unit that has detected it cannot really
513 * "close" the "no suspend" period associated with it, unless it knows in
514 * advance what's going to happen to the event during processing. This
515 * knowledge, however, may not be available to it, so it can simply specify time
516 * to wait before the system can be suspended and pass it as the second
517 * argument of pm_wakeup_event().
518 *
519 * It is valid to call pm_relax() after pm_wakeup_event(), in which case the
520 * "no suspend" period will be ended either by the pm_relax(), or by the timer
521 * function executed when the timer expires, whichever comes first.
522 */
523
524/**
525 * wakup_source_activate - Mark given wakeup source as active.
526 * @ws: Wakeup source to handle.
527 *
528 * Update the @ws' statistics and, if @ws has just been activated, notify the PM
529 * core of the event by incrementing the counter of of wakeup events being
530 * processed.
531 */
532static void wakeup_source_activate(struct wakeup_source *ws)
533{
534 unsigned int cec;
535
536 if (WARN_ONCE(wakeup_source_not_registered(ws),
537 "unregistered wakeup source\n"))
538 return;
539
540 ws->active = true;
541 ws->active_count++;
542 ws->last_time = ktime_get();
543 if (ws->autosleep_enabled)
544 ws->start_prevent_time = ws->last_time;
545
546 /* Increment the counter of events in progress. */
547 cec = atomic_inc_return(&combined_event_count);
548
549 trace_wakeup_source_activate(ws->name, cec);
550}
551
552/**
553 * wakeup_source_report_event - Report wakeup event using the given source.
554 * @ws: Wakeup source to report the event for.
555 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
556 */
557static void wakeup_source_report_event(struct wakeup_source *ws, bool hard)
558{
559 ws->event_count++;
560 /* This is racy, but the counter is approximate anyway. */
561 if (events_check_enabled)
562 ws->wakeup_count++;
563
564 if (!ws->active)
565 wakeup_source_activate(ws);
566
567 if (hard)
568 pm_system_wakeup();
569}
570
571/**
572 * __pm_stay_awake - Notify the PM core of a wakeup event.
573 * @ws: Wakeup source object associated with the source of the event.
574 *
575 * It is safe to call this function from interrupt context.
576 */
577void __pm_stay_awake(struct wakeup_source *ws)
578{
579 unsigned long flags;
580
581 if (!ws)
582 return;
583
584 spin_lock_irqsave(&ws->lock, flags);
585
586 wakeup_source_report_event(ws, false);
587 del_timer(&ws->timer);
588 ws->timer_expires = 0;
589
590 spin_unlock_irqrestore(&ws->lock, flags);
591}
592EXPORT_SYMBOL_GPL(__pm_stay_awake);
593
594/**
595 * pm_stay_awake - Notify the PM core that a wakeup event is being processed.
596 * @dev: Device the wakeup event is related to.
597 *
598 * Notify the PM core of a wakeup event (signaled by @dev) by calling
599 * __pm_stay_awake for the @dev's wakeup source object.
600 *
601 * Call this function after detecting of a wakeup event if pm_relax() is going
602 * to be called directly after processing the event (and possibly passing it to
603 * user space for further processing).
604 */
605void pm_stay_awake(struct device *dev)
606{
607 unsigned long flags;
608
609 if (!dev)
610 return;
611
612 spin_lock_irqsave(&dev->power.lock, flags);
613 __pm_stay_awake(dev->power.wakeup);
614 spin_unlock_irqrestore(&dev->power.lock, flags);
615}
616EXPORT_SYMBOL_GPL(pm_stay_awake);
617
618#ifdef CONFIG_PM_AUTOSLEEP
619static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now)
620{
621 ktime_t delta = ktime_sub(now, ws->start_prevent_time);
622 ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta);
623}
624#else
625static inline void update_prevent_sleep_time(struct wakeup_source *ws,
626 ktime_t now) {}
627#endif
628
629/**
630 * wakup_source_deactivate - Mark given wakeup source as inactive.
631 * @ws: Wakeup source to handle.
632 *
633 * Update the @ws' statistics and notify the PM core that the wakeup source has
634 * become inactive by decrementing the counter of wakeup events being processed
635 * and incrementing the counter of registered wakeup events.
636 */
637static void wakeup_source_deactivate(struct wakeup_source *ws)
638{
639 unsigned int cnt, inpr, cec;
640 ktime_t duration;
641 ktime_t now;
642
643 ws->relax_count++;
644 /*
645 * __pm_relax() may be called directly or from a timer function.
646 * If it is called directly right after the timer function has been
647 * started, but before the timer function calls __pm_relax(), it is
648 * possible that __pm_stay_awake() will be called in the meantime and
649 * will set ws->active. Then, ws->active may be cleared immediately
650 * by the __pm_relax() called from the timer function, but in such a
651 * case ws->relax_count will be different from ws->active_count.
652 */
653 if (ws->relax_count != ws->active_count) {
654 ws->relax_count--;
655 return;
656 }
657
658 ws->active = false;
659
660 now = ktime_get();
661 duration = ktime_sub(now, ws->last_time);
662 ws->total_time = ktime_add(ws->total_time, duration);
663 if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
664 ws->max_time = duration;
665
666 ws->last_time = now;
667 del_timer(&ws->timer);
668 ws->timer_expires = 0;
669
670 if (ws->autosleep_enabled)
671 update_prevent_sleep_time(ws, now);
672
673 /*
674 * Increment the counter of registered wakeup events and decrement the
675 * couter of wakeup events in progress simultaneously.
676 */
677 cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count);
678 trace_wakeup_source_deactivate(ws->name, cec);
679
680 split_counters(&cnt, &inpr);
681 if (!inpr && waitqueue_active(&wakeup_count_wait_queue))
682 wake_up(&wakeup_count_wait_queue);
683}
684
685/**
686 * __pm_relax - Notify the PM core that processing of a wakeup event has ended.
687 * @ws: Wakeup source object associated with the source of the event.
688 *
689 * Call this function for wakeup events whose processing started with calling
690 * __pm_stay_awake().
691 *
692 * It is safe to call it from interrupt context.
693 */
694void __pm_relax(struct wakeup_source *ws)
695{
696 unsigned long flags;
697
698 if (!ws)
699 return;
700
701 spin_lock_irqsave(&ws->lock, flags);
702 if (ws->active)
703 wakeup_source_deactivate(ws);
704 spin_unlock_irqrestore(&ws->lock, flags);
705}
706EXPORT_SYMBOL_GPL(__pm_relax);
707
708/**
709 * pm_relax - Notify the PM core that processing of a wakeup event has ended.
710 * @dev: Device that signaled the event.
711 *
712 * Execute __pm_relax() for the @dev's wakeup source object.
713 */
714void pm_relax(struct device *dev)
715{
716 unsigned long flags;
717
718 if (!dev)
719 return;
720
721 spin_lock_irqsave(&dev->power.lock, flags);
722 __pm_relax(dev->power.wakeup);
723 spin_unlock_irqrestore(&dev->power.lock, flags);
724}
725EXPORT_SYMBOL_GPL(pm_relax);
726
727/**
728 * pm_wakeup_timer_fn - Delayed finalization of a wakeup event.
729 * @data: Address of the wakeup source object associated with the event source.
730 *
731 * Call wakeup_source_deactivate() for the wakeup source whose address is stored
732 * in @data if it is currently active and its timer has not been canceled and
733 * the expiration time of the timer is not in future.
734 */
735static void pm_wakeup_timer_fn(struct timer_list *t)
736{
737 struct wakeup_source *ws = from_timer(ws, t, timer);
738 unsigned long flags;
739
740 spin_lock_irqsave(&ws->lock, flags);
741
742 if (ws->active && ws->timer_expires
743 && time_after_eq(jiffies, ws->timer_expires)) {
744 wakeup_source_deactivate(ws);
745 ws->expire_count++;
746 }
747
748 spin_unlock_irqrestore(&ws->lock, flags);
749}
750
751/**
752 * pm_wakeup_ws_event - Notify the PM core of a wakeup event.
753 * @ws: Wakeup source object associated with the event source.
754 * @msec: Anticipated event processing time (in milliseconds).
755 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
756 *
757 * Notify the PM core of a wakeup event whose source is @ws that will take
758 * approximately @msec milliseconds to be processed by the kernel. If @ws is
759 * not active, activate it. If @msec is nonzero, set up the @ws' timer to
760 * execute pm_wakeup_timer_fn() in future.
761 *
762 * It is safe to call this function from interrupt context.
763 */
764void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard)
765{
766 unsigned long flags;
767 unsigned long expires;
768
769 if (!ws)
770 return;
771
772 spin_lock_irqsave(&ws->lock, flags);
773
774 wakeup_source_report_event(ws, hard);
775
776 if (!msec) {
777 wakeup_source_deactivate(ws);
778 goto unlock;
779 }
780
781 expires = jiffies + msecs_to_jiffies(msec);
782 if (!expires)
783 expires = 1;
784
785 if (!ws->timer_expires || time_after(expires, ws->timer_expires)) {
786 mod_timer(&ws->timer, expires);
787 ws->timer_expires = expires;
788 }
789
790 unlock:
791 spin_unlock_irqrestore(&ws->lock, flags);
792}
793EXPORT_SYMBOL_GPL(pm_wakeup_ws_event);
794
795/**
796 * pm_wakeup_dev_event - Notify the PM core of a wakeup event.
797 * @dev: Device the wakeup event is related to.
798 * @msec: Anticipated event processing time (in milliseconds).
799 * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
800 *
801 * Call pm_wakeup_ws_event() for the @dev's wakeup source object.
802 */
803void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard)
804{
805 unsigned long flags;
806
807 if (!dev)
808 return;
809
810 spin_lock_irqsave(&dev->power.lock, flags);
811 pm_wakeup_ws_event(dev->power.wakeup, msec, hard);
812 spin_unlock_irqrestore(&dev->power.lock, flags);
813}
814EXPORT_SYMBOL_GPL(pm_wakeup_dev_event);
815
816void pm_print_active_wakeup_sources(void)
817{
818 struct wakeup_source *ws;
819 int srcuidx, active = 0;
820 struct wakeup_source *last_activity_ws = NULL;
821
822 srcuidx = srcu_read_lock(&wakeup_srcu);
823 list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
824 if (ws->active) {
825 pm_pr_dbg("active wakeup source: %s\n", ws->name);
826 active = 1;
827 } else if (!active &&
828 (!last_activity_ws ||
829 ktime_to_ns(ws->last_time) >
830 ktime_to_ns(last_activity_ws->last_time))) {
831 last_activity_ws = ws;
832 }
833 }
834
835 if (!active && last_activity_ws)
836 pm_pr_dbg("last active wakeup source: %s\n",
837 last_activity_ws->name);
838 srcu_read_unlock(&wakeup_srcu, srcuidx);
839}
840EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources);
841
842/**
843 * pm_wakeup_pending - Check if power transition in progress should be aborted.
844 *
845 * Compare the current number of registered wakeup events with its preserved
846 * value from the past and return true if new wakeup events have been registered
847 * since the old value was stored. Also return true if the current number of
848 * wakeup events being processed is different from zero.
849 */
850bool pm_wakeup_pending(void)
851{
852 unsigned long flags;
853 bool ret = false;
854
855 raw_spin_lock_irqsave(&events_lock, flags);
856 if (events_check_enabled) {
857 unsigned int cnt, inpr;
858
859 split_counters(&cnt, &inpr);
860 ret = (cnt != saved_count || inpr > 0);
861 events_check_enabled = !ret;
862 }
863 raw_spin_unlock_irqrestore(&events_lock, flags);
864
865 if (ret) {
866 pm_pr_dbg("Wakeup pending, aborting suspend\n");
867 pm_print_active_wakeup_sources();
868 }
869
870 return ret || atomic_read(&pm_abort_suspend) > 0;
871}
872
873void pm_system_wakeup(void)
874{
875 atomic_inc(&pm_abort_suspend);
876 s2idle_wake();
877}
878EXPORT_SYMBOL_GPL(pm_system_wakeup);
879
880void pm_system_cancel_wakeup(void)
881{
882 atomic_dec_if_positive(&pm_abort_suspend);
883}
884
885void pm_wakeup_clear(bool reset)
886{
887 pm_wakeup_irq = 0;
888 if (reset)
889 atomic_set(&pm_abort_suspend, 0);
890}
891
892void pm_system_irq_wakeup(unsigned int irq_number)
893{
894 if (pm_wakeup_irq == 0) {
895 pm_wakeup_irq = irq_number;
896 pm_system_wakeup();
897 }
898}
899
900/**
901 * pm_get_wakeup_count - Read the number of registered wakeup events.
902 * @count: Address to store the value at.
903 * @block: Whether or not to block.
904 *
905 * Store the number of registered wakeup events at the address in @count. If
906 * @block is set, block until the current number of wakeup events being
907 * processed is zero.
908 *
909 * Return 'false' if the current number of wakeup events being processed is
910 * nonzero. Otherwise return 'true'.
911 */
912bool pm_get_wakeup_count(unsigned int *count, bool block)
913{
914 unsigned int cnt, inpr;
915
916 if (block) {
917 DEFINE_WAIT(wait);
918
919 for (;;) {
920 prepare_to_wait(&wakeup_count_wait_queue, &wait,
921 TASK_INTERRUPTIBLE);
922 split_counters(&cnt, &inpr);
923 if (inpr == 0 || signal_pending(current))
924 break;
925 pm_print_active_wakeup_sources();
926 schedule();
927 }
928 finish_wait(&wakeup_count_wait_queue, &wait);
929 }
930
931 split_counters(&cnt, &inpr);
932 *count = cnt;
933 return !inpr;
934}
935
936/**
937 * pm_save_wakeup_count - Save the current number of registered wakeup events.
938 * @count: Value to compare with the current number of registered wakeup events.
939 *
940 * If @count is equal to the current number of registered wakeup events and the
941 * current number of wakeup events being processed is zero, store @count as the
942 * old number of registered wakeup events for pm_check_wakeup_events(), enable
943 * wakeup events detection and return 'true'. Otherwise disable wakeup events
944 * detection and return 'false'.
945 */
946bool pm_save_wakeup_count(unsigned int count)
947{
948 unsigned int cnt, inpr;
949 unsigned long flags;
950
951 events_check_enabled = false;
952 raw_spin_lock_irqsave(&events_lock, flags);
953 split_counters(&cnt, &inpr);
954 if (cnt == count && inpr == 0) {
955 saved_count = count;
956 events_check_enabled = true;
957 }
958 raw_spin_unlock_irqrestore(&events_lock, flags);
959 return events_check_enabled;
960}
961
962#ifdef CONFIG_PM_AUTOSLEEP
963/**
964 * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources.
965 * @enabled: Whether to set or to clear the autosleep_enabled flags.
966 */
967void pm_wakep_autosleep_enabled(bool set)
968{
969 struct wakeup_source *ws;
970 ktime_t now = ktime_get();
971 int srcuidx;
972
973 srcuidx = srcu_read_lock(&wakeup_srcu);
974 list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
975 spin_lock_irq(&ws->lock);
976 if (ws->autosleep_enabled != set) {
977 ws->autosleep_enabled = set;
978 if (ws->active) {
979 if (set)
980 ws->start_prevent_time = now;
981 else
982 update_prevent_sleep_time(ws, now);
983 }
984 }
985 spin_unlock_irq(&ws->lock);
986 }
987 srcu_read_unlock(&wakeup_srcu, srcuidx);
988}
989#endif /* CONFIG_PM_AUTOSLEEP */
990
991/**
992 * print_wakeup_source_stats - Print wakeup source statistics information.
993 * @m: seq_file to print the statistics into.
994 * @ws: Wakeup source object to print the statistics for.
995 */
996static int print_wakeup_source_stats(struct seq_file *m,
997 struct wakeup_source *ws)
998{
999 unsigned long flags;
1000 ktime_t total_time;
1001 ktime_t max_time;
1002 unsigned long active_count;
1003 ktime_t active_time;
1004 ktime_t prevent_sleep_time;
1005
1006 spin_lock_irqsave(&ws->lock, flags);
1007
1008 total_time = ws->total_time;
1009 max_time = ws->max_time;
1010 prevent_sleep_time = ws->prevent_sleep_time;
1011 active_count = ws->active_count;
1012 if (ws->active) {
1013 ktime_t now = ktime_get();
1014
1015 active_time = ktime_sub(now, ws->last_time);
1016 total_time = ktime_add(total_time, active_time);
1017 if (active_time > max_time)
1018 max_time = active_time;
1019
1020 if (ws->autosleep_enabled)
1021 prevent_sleep_time = ktime_add(prevent_sleep_time,
1022 ktime_sub(now, ws->start_prevent_time));
1023 } else {
1024 active_time = 0;
1025 }
1026
1027 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",
1028 ws->name, active_count, ws->event_count,
1029 ws->wakeup_count, ws->expire_count,
1030 ktime_to_ms(active_time), ktime_to_ms(total_time),
1031 ktime_to_ms(max_time), ktime_to_ms(ws->last_time),
1032 ktime_to_ms(prevent_sleep_time));
1033
1034 spin_unlock_irqrestore(&ws->lock, flags);
1035
1036 return 0;
1037}
1038
1039static void *wakeup_sources_stats_seq_start(struct seq_file *m,
1040 loff_t *pos)
1041{
1042 struct wakeup_source *ws;
1043 loff_t n = *pos;
1044 int *srcuidx = m->private;
1045
1046 if (n == 0) {
1047 seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"
1048 "expire_count\tactive_since\ttotal_time\tmax_time\t"
1049 "last_change\tprevent_suspend_time\n");
1050 }
1051
1052 *srcuidx = srcu_read_lock(&wakeup_srcu);
1053 list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
1054 if (n-- <= 0)
1055 return ws;
1056 }
1057
1058 return NULL;
1059}
1060
1061static void *wakeup_sources_stats_seq_next(struct seq_file *m,
1062 void *v, loff_t *pos)
1063{
1064 struct wakeup_source *ws = v;
1065 struct wakeup_source *next_ws = NULL;
1066
1067 ++(*pos);
1068
1069 list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) {
1070 next_ws = ws;
1071 break;
1072 }
1073
1074 return next_ws;
1075}
1076
1077static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v)
1078{
1079 int *srcuidx = m->private;
1080
1081 srcu_read_unlock(&wakeup_srcu, *srcuidx);
1082}
1083
1084/**
1085 * wakeup_sources_stats_seq_show - Print wakeup sources statistics information.
1086 * @m: seq_file to print the statistics into.
1087 * @v: wakeup_source of each iteration
1088 */
1089static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v)
1090{
1091 struct wakeup_source *ws = v;
1092
1093 print_wakeup_source_stats(m, ws);
1094
1095 return 0;
1096}
1097
1098static const struct seq_operations wakeup_sources_stats_seq_ops = {
1099 .start = wakeup_sources_stats_seq_start,
1100 .next = wakeup_sources_stats_seq_next,
1101 .stop = wakeup_sources_stats_seq_stop,
1102 .show = wakeup_sources_stats_seq_show,
1103};
1104
1105static int wakeup_sources_stats_open(struct inode *inode, struct file *file)
1106{
1107 return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int));
1108}
1109
1110static const struct file_operations wakeup_sources_stats_fops = {
1111 .owner = THIS_MODULE,
1112 .open = wakeup_sources_stats_open,
1113 .read = seq_read,
1114 .llseek = seq_lseek,
1115 .release = seq_release_private,
1116};
1117
1118static int __init wakeup_sources_debugfs_init(void)
1119{
1120 debugfs_create_file("wakeup_sources", S_IRUGO, NULL, NULL,
1121 &wakeup_sources_stats_fops);
1122 return 0;
1123}
1124
1125postcore_initcall(wakeup_sources_debugfs_init);