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c125e96f RW |
1 | /* |
2 | * drivers/base/power/wakeup.c - System wakeup events framework | |
3 | * | |
4 | * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. | |
5 | * | |
6 | * This file is released under the GPLv2. | |
7 | */ | |
8 | ||
9 | #include <linux/device.h> | |
10 | #include <linux/slab.h> | |
11 | #include <linux/sched.h> | |
12 | #include <linux/capability.h> | |
1b6bc32f | 13 | #include <linux/export.h> |
c125e96f | 14 | #include <linux/suspend.h> |
9c034392 RW |
15 | #include <linux/seq_file.h> |
16 | #include <linux/debugfs.h> | |
6791e36c | 17 | #include <trace/events/power.h> |
074037ec RW |
18 | |
19 | #include "power.h" | |
20 | ||
c125e96f RW |
21 | /* |
22 | * If set, the suspend/hibernate code will abort transitions to a sleep state | |
23 | * if wakeup events are registered during or immediately before the transition. | |
24 | */ | |
30e3ce6d | 25 | bool events_check_enabled __read_mostly; |
c125e96f | 26 | |
023d3779 RW |
27 | /* |
28 | * Combined counters of registered wakeup events and wakeup events in progress. | |
29 | * They need to be modified together atomically, so it's better to use one | |
30 | * atomic variable to hold them both. | |
31 | */ | |
32 | static atomic_t combined_event_count = ATOMIC_INIT(0); | |
33 | ||
34 | #define IN_PROGRESS_BITS (sizeof(int) * 4) | |
35 | #define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1) | |
36 | ||
37 | static void split_counters(unsigned int *cnt, unsigned int *inpr) | |
38 | { | |
39 | unsigned int comb = atomic_read(&combined_event_count); | |
40 | ||
41 | *cnt = (comb >> IN_PROGRESS_BITS); | |
42 | *inpr = comb & MAX_IN_PROGRESS; | |
43 | } | |
44 | ||
45 | /* A preserved old value of the events counter. */ | |
074037ec | 46 | static unsigned int saved_count; |
c125e96f RW |
47 | |
48 | static DEFINE_SPINLOCK(events_lock); | |
49 | ||
4eb241e5 RW |
50 | static void pm_wakeup_timer_fn(unsigned long data); |
51 | ||
074037ec RW |
52 | static LIST_HEAD(wakeup_sources); |
53 | ||
60af1066 RW |
54 | static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue); |
55 | ||
8671bbc1 RW |
56 | /** |
57 | * wakeup_source_prepare - Prepare a new wakeup source for initialization. | |
58 | * @ws: Wakeup source to prepare. | |
59 | * @name: Pointer to the name of the new wakeup source. | |
60 | * | |
61 | * Callers must ensure that the @name string won't be freed when @ws is still in | |
62 | * use. | |
63 | */ | |
64 | void wakeup_source_prepare(struct wakeup_source *ws, const char *name) | |
65 | { | |
66 | if (ws) { | |
67 | memset(ws, 0, sizeof(*ws)); | |
68 | ws->name = name; | |
69 | } | |
70 | } | |
71 | EXPORT_SYMBOL_GPL(wakeup_source_prepare); | |
72 | ||
074037ec RW |
73 | /** |
74 | * wakeup_source_create - Create a struct wakeup_source object. | |
75 | * @name: Name of the new wakeup source. | |
76 | */ | |
77 | struct wakeup_source *wakeup_source_create(const char *name) | |
78 | { | |
79 | struct wakeup_source *ws; | |
80 | ||
8671bbc1 | 81 | ws = kmalloc(sizeof(*ws), GFP_KERNEL); |
074037ec RW |
82 | if (!ws) |
83 | return NULL; | |
84 | ||
8671bbc1 | 85 | wakeup_source_prepare(ws, name ? kstrdup(name, GFP_KERNEL) : NULL); |
074037ec RW |
86 | return ws; |
87 | } | |
88 | EXPORT_SYMBOL_GPL(wakeup_source_create); | |
89 | ||
90 | /** | |
8671bbc1 RW |
91 | * wakeup_source_drop - Prepare a struct wakeup_source object for destruction. |
92 | * @ws: Wakeup source to prepare for destruction. | |
d94aff87 RW |
93 | * |
94 | * Callers must ensure that __pm_stay_awake() or __pm_wakeup_event() will never | |
95 | * be run in parallel with this function for the same wakeup source object. | |
074037ec | 96 | */ |
8671bbc1 | 97 | void wakeup_source_drop(struct wakeup_source *ws) |
074037ec RW |
98 | { |
99 | if (!ws) | |
100 | return; | |
101 | ||
d94aff87 RW |
102 | del_timer_sync(&ws->timer); |
103 | __pm_relax(ws); | |
8671bbc1 RW |
104 | } |
105 | EXPORT_SYMBOL_GPL(wakeup_source_drop); | |
106 | ||
107 | /** | |
108 | * wakeup_source_destroy - Destroy a struct wakeup_source object. | |
109 | * @ws: Wakeup source to destroy. | |
110 | * | |
111 | * Use only for wakeup source objects created with wakeup_source_create(). | |
112 | */ | |
113 | void wakeup_source_destroy(struct wakeup_source *ws) | |
114 | { | |
115 | if (!ws) | |
116 | return; | |
117 | ||
118 | wakeup_source_drop(ws); | |
074037ec RW |
119 | kfree(ws->name); |
120 | kfree(ws); | |
121 | } | |
122 | EXPORT_SYMBOL_GPL(wakeup_source_destroy); | |
123 | ||
124 | /** | |
125 | * wakeup_source_add - Add given object to the list of wakeup sources. | |
126 | * @ws: Wakeup source object to add to the list. | |
127 | */ | |
128 | void wakeup_source_add(struct wakeup_source *ws) | |
129 | { | |
49550709 JS |
130 | unsigned long flags; |
131 | ||
074037ec RW |
132 | if (WARN_ON(!ws)) |
133 | return; | |
134 | ||
7c95149b | 135 | spin_lock_init(&ws->lock); |
074037ec RW |
136 | setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws); |
137 | ws->active = false; | |
b86ff982 | 138 | ws->last_time = ktime_get(); |
074037ec | 139 | |
49550709 | 140 | spin_lock_irqsave(&events_lock, flags); |
074037ec | 141 | list_add_rcu(&ws->entry, &wakeup_sources); |
49550709 | 142 | spin_unlock_irqrestore(&events_lock, flags); |
074037ec RW |
143 | } |
144 | EXPORT_SYMBOL_GPL(wakeup_source_add); | |
145 | ||
146 | /** | |
147 | * wakeup_source_remove - Remove given object from the wakeup sources list. | |
148 | * @ws: Wakeup source object to remove from the list. | |
149 | */ | |
150 | void wakeup_source_remove(struct wakeup_source *ws) | |
151 | { | |
49550709 JS |
152 | unsigned long flags; |
153 | ||
074037ec RW |
154 | if (WARN_ON(!ws)) |
155 | return; | |
156 | ||
49550709 | 157 | spin_lock_irqsave(&events_lock, flags); |
074037ec | 158 | list_del_rcu(&ws->entry); |
49550709 | 159 | spin_unlock_irqrestore(&events_lock, flags); |
074037ec RW |
160 | synchronize_rcu(); |
161 | } | |
162 | EXPORT_SYMBOL_GPL(wakeup_source_remove); | |
163 | ||
164 | /** | |
165 | * wakeup_source_register - Create wakeup source and add it to the list. | |
166 | * @name: Name of the wakeup source to register. | |
167 | */ | |
168 | struct wakeup_source *wakeup_source_register(const char *name) | |
169 | { | |
170 | struct wakeup_source *ws; | |
171 | ||
172 | ws = wakeup_source_create(name); | |
173 | if (ws) | |
174 | wakeup_source_add(ws); | |
175 | ||
176 | return ws; | |
177 | } | |
178 | EXPORT_SYMBOL_GPL(wakeup_source_register); | |
179 | ||
180 | /** | |
181 | * wakeup_source_unregister - Remove wakeup source from the list and remove it. | |
182 | * @ws: Wakeup source object to unregister. | |
183 | */ | |
184 | void wakeup_source_unregister(struct wakeup_source *ws) | |
185 | { | |
8671bbc1 RW |
186 | if (ws) { |
187 | wakeup_source_remove(ws); | |
188 | wakeup_source_destroy(ws); | |
189 | } | |
074037ec RW |
190 | } |
191 | EXPORT_SYMBOL_GPL(wakeup_source_unregister); | |
192 | ||
193 | /** | |
194 | * device_wakeup_attach - Attach a wakeup source object to a device object. | |
195 | * @dev: Device to handle. | |
196 | * @ws: Wakeup source object to attach to @dev. | |
197 | * | |
198 | * This causes @dev to be treated as a wakeup device. | |
199 | */ | |
200 | static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) | |
201 | { | |
202 | spin_lock_irq(&dev->power.lock); | |
203 | if (dev->power.wakeup) { | |
204 | spin_unlock_irq(&dev->power.lock); | |
205 | return -EEXIST; | |
206 | } | |
207 | dev->power.wakeup = ws; | |
208 | spin_unlock_irq(&dev->power.lock); | |
209 | return 0; | |
210 | } | |
211 | ||
212 | /** | |
213 | * device_wakeup_enable - Enable given device to be a wakeup source. | |
214 | * @dev: Device to handle. | |
215 | * | |
216 | * Create a wakeup source object, register it and attach it to @dev. | |
217 | */ | |
218 | int device_wakeup_enable(struct device *dev) | |
219 | { | |
220 | struct wakeup_source *ws; | |
221 | int ret; | |
222 | ||
223 | if (!dev || !dev->power.can_wakeup) | |
224 | return -EINVAL; | |
225 | ||
226 | ws = wakeup_source_register(dev_name(dev)); | |
227 | if (!ws) | |
228 | return -ENOMEM; | |
229 | ||
230 | ret = device_wakeup_attach(dev, ws); | |
231 | if (ret) | |
232 | wakeup_source_unregister(ws); | |
233 | ||
234 | return ret; | |
235 | } | |
236 | EXPORT_SYMBOL_GPL(device_wakeup_enable); | |
237 | ||
238 | /** | |
239 | * device_wakeup_detach - Detach a device's wakeup source object from it. | |
240 | * @dev: Device to detach the wakeup source object from. | |
241 | * | |
242 | * After it returns, @dev will not be treated as a wakeup device any more. | |
243 | */ | |
244 | static struct wakeup_source *device_wakeup_detach(struct device *dev) | |
245 | { | |
246 | struct wakeup_source *ws; | |
247 | ||
248 | spin_lock_irq(&dev->power.lock); | |
249 | ws = dev->power.wakeup; | |
250 | dev->power.wakeup = NULL; | |
251 | spin_unlock_irq(&dev->power.lock); | |
252 | return ws; | |
253 | } | |
254 | ||
255 | /** | |
256 | * device_wakeup_disable - Do not regard a device as a wakeup source any more. | |
257 | * @dev: Device to handle. | |
258 | * | |
259 | * Detach the @dev's wakeup source object from it, unregister this wakeup source | |
260 | * object and destroy it. | |
261 | */ | |
262 | int device_wakeup_disable(struct device *dev) | |
263 | { | |
264 | struct wakeup_source *ws; | |
265 | ||
266 | if (!dev || !dev->power.can_wakeup) | |
267 | return -EINVAL; | |
268 | ||
269 | ws = device_wakeup_detach(dev); | |
270 | if (ws) | |
271 | wakeup_source_unregister(ws); | |
272 | ||
273 | return 0; | |
274 | } | |
275 | EXPORT_SYMBOL_GPL(device_wakeup_disable); | |
276 | ||
cb8f51bd RW |
277 | /** |
278 | * device_set_wakeup_capable - Set/reset device wakeup capability flag. | |
279 | * @dev: Device to handle. | |
280 | * @capable: Whether or not @dev is capable of waking up the system from sleep. | |
281 | * | |
282 | * If @capable is set, set the @dev's power.can_wakeup flag and add its | |
283 | * wakeup-related attributes to sysfs. Otherwise, unset the @dev's | |
284 | * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. | |
285 | * | |
286 | * This function may sleep and it can't be called from any context where | |
287 | * sleeping is not allowed. | |
288 | */ | |
289 | void device_set_wakeup_capable(struct device *dev, bool capable) | |
290 | { | |
291 | if (!!dev->power.can_wakeup == !!capable) | |
292 | return; | |
293 | ||
22110faf | 294 | if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { |
cb8f51bd RW |
295 | if (capable) { |
296 | if (wakeup_sysfs_add(dev)) | |
297 | return; | |
298 | } else { | |
299 | wakeup_sysfs_remove(dev); | |
300 | } | |
301 | } | |
302 | dev->power.can_wakeup = capable; | |
303 | } | |
304 | EXPORT_SYMBOL_GPL(device_set_wakeup_capable); | |
305 | ||
074037ec RW |
306 | /** |
307 | * device_init_wakeup - Device wakeup initialization. | |
308 | * @dev: Device to handle. | |
309 | * @enable: Whether or not to enable @dev as a wakeup device. | |
310 | * | |
311 | * By default, most devices should leave wakeup disabled. The exceptions are | |
312 | * devices that everyone expects to be wakeup sources: keyboards, power buttons, | |
8f88893c AS |
313 | * possibly network interfaces, etc. Also, devices that don't generate their |
314 | * own wakeup requests but merely forward requests from one bus to another | |
315 | * (like PCI bridges) should have wakeup enabled by default. | |
074037ec RW |
316 | */ |
317 | int device_init_wakeup(struct device *dev, bool enable) | |
318 | { | |
319 | int ret = 0; | |
320 | ||
321 | if (enable) { | |
322 | device_set_wakeup_capable(dev, true); | |
323 | ret = device_wakeup_enable(dev); | |
324 | } else { | |
325 | device_set_wakeup_capable(dev, false); | |
326 | } | |
327 | ||
328 | return ret; | |
329 | } | |
330 | EXPORT_SYMBOL_GPL(device_init_wakeup); | |
331 | ||
332 | /** | |
333 | * device_set_wakeup_enable - Enable or disable a device to wake up the system. | |
334 | * @dev: Device to handle. | |
335 | */ | |
336 | int device_set_wakeup_enable(struct device *dev, bool enable) | |
337 | { | |
338 | if (!dev || !dev->power.can_wakeup) | |
339 | return -EINVAL; | |
340 | ||
341 | return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev); | |
342 | } | |
343 | EXPORT_SYMBOL_GPL(device_set_wakeup_enable); | |
4eb241e5 | 344 | |
c125e96f RW |
345 | /* |
346 | * The functions below use the observation that each wakeup event starts a | |
347 | * period in which the system should not be suspended. The moment this period | |
348 | * will end depends on how the wakeup event is going to be processed after being | |
349 | * detected and all of the possible cases can be divided into two distinct | |
350 | * groups. | |
351 | * | |
352 | * First, a wakeup event may be detected by the same functional unit that will | |
353 | * carry out the entire processing of it and possibly will pass it to user space | |
354 | * for further processing. In that case the functional unit that has detected | |
355 | * the event may later "close" the "no suspend" period associated with it | |
356 | * directly as soon as it has been dealt with. The pair of pm_stay_awake() and | |
357 | * pm_relax(), balanced with each other, is supposed to be used in such | |
358 | * situations. | |
359 | * | |
360 | * Second, a wakeup event may be detected by one functional unit and processed | |
361 | * by another one. In that case the unit that has detected it cannot really | |
362 | * "close" the "no suspend" period associated with it, unless it knows in | |
363 | * advance what's going to happen to the event during processing. This | |
364 | * knowledge, however, may not be available to it, so it can simply specify time | |
365 | * to wait before the system can be suspended and pass it as the second | |
366 | * argument of pm_wakeup_event(). | |
074037ec RW |
367 | * |
368 | * It is valid to call pm_relax() after pm_wakeup_event(), in which case the | |
369 | * "no suspend" period will be ended either by the pm_relax(), or by the timer | |
370 | * function executed when the timer expires, whichever comes first. | |
c125e96f RW |
371 | */ |
372 | ||
074037ec RW |
373 | /** |
374 | * wakup_source_activate - Mark given wakeup source as active. | |
375 | * @ws: Wakeup source to handle. | |
376 | * | |
377 | * Update the @ws' statistics and, if @ws has just been activated, notify the PM | |
378 | * core of the event by incrementing the counter of of wakeup events being | |
379 | * processed. | |
380 | */ | |
381 | static void wakeup_source_activate(struct wakeup_source *ws) | |
382 | { | |
6791e36c AH |
383 | unsigned int cec; |
384 | ||
074037ec RW |
385 | ws->active = true; |
386 | ws->active_count++; | |
074037ec | 387 | ws->last_time = ktime_get(); |
55850945 RW |
388 | if (ws->autosleep_enabled) |
389 | ws->start_prevent_time = ws->last_time; | |
074037ec | 390 | |
023d3779 | 391 | /* Increment the counter of events in progress. */ |
6791e36c AH |
392 | cec = atomic_inc_return(&combined_event_count); |
393 | ||
394 | trace_wakeup_source_activate(ws->name, cec); | |
074037ec RW |
395 | } |
396 | ||
30e3ce6d RW |
397 | /** |
398 | * wakeup_source_report_event - Report wakeup event using the given source. | |
399 | * @ws: Wakeup source to report the event for. | |
400 | */ | |
401 | static void wakeup_source_report_event(struct wakeup_source *ws) | |
402 | { | |
403 | ws->event_count++; | |
404 | /* This is racy, but the counter is approximate anyway. */ | |
405 | if (events_check_enabled) | |
406 | ws->wakeup_count++; | |
407 | ||
408 | if (!ws->active) | |
409 | wakeup_source_activate(ws); | |
410 | } | |
411 | ||
074037ec RW |
412 | /** |
413 | * __pm_stay_awake - Notify the PM core of a wakeup event. | |
414 | * @ws: Wakeup source object associated with the source of the event. | |
415 | * | |
416 | * It is safe to call this function from interrupt context. | |
417 | */ | |
418 | void __pm_stay_awake(struct wakeup_source *ws) | |
419 | { | |
420 | unsigned long flags; | |
421 | ||
422 | if (!ws) | |
423 | return; | |
424 | ||
425 | spin_lock_irqsave(&ws->lock, flags); | |
4782e165 | 426 | |
30e3ce6d | 427 | wakeup_source_report_event(ws); |
4782e165 RW |
428 | del_timer(&ws->timer); |
429 | ws->timer_expires = 0; | |
430 | ||
074037ec RW |
431 | spin_unlock_irqrestore(&ws->lock, flags); |
432 | } | |
433 | EXPORT_SYMBOL_GPL(__pm_stay_awake); | |
434 | ||
c125e96f RW |
435 | /** |
436 | * pm_stay_awake - Notify the PM core that a wakeup event is being processed. | |
437 | * @dev: Device the wakeup event is related to. | |
438 | * | |
074037ec RW |
439 | * Notify the PM core of a wakeup event (signaled by @dev) by calling |
440 | * __pm_stay_awake for the @dev's wakeup source object. | |
c125e96f RW |
441 | * |
442 | * Call this function after detecting of a wakeup event if pm_relax() is going | |
443 | * to be called directly after processing the event (and possibly passing it to | |
444 | * user space for further processing). | |
c125e96f RW |
445 | */ |
446 | void pm_stay_awake(struct device *dev) | |
447 | { | |
448 | unsigned long flags; | |
449 | ||
074037ec RW |
450 | if (!dev) |
451 | return; | |
c125e96f | 452 | |
074037ec RW |
453 | spin_lock_irqsave(&dev->power.lock, flags); |
454 | __pm_stay_awake(dev->power.wakeup); | |
455 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 456 | } |
074037ec | 457 | EXPORT_SYMBOL_GPL(pm_stay_awake); |
c125e96f | 458 | |
55850945 RW |
459 | #ifdef CONFIG_PM_AUTOSLEEP |
460 | static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now) | |
461 | { | |
462 | ktime_t delta = ktime_sub(now, ws->start_prevent_time); | |
463 | ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta); | |
464 | } | |
465 | #else | |
466 | static inline void update_prevent_sleep_time(struct wakeup_source *ws, | |
467 | ktime_t now) {} | |
468 | #endif | |
469 | ||
c125e96f | 470 | /** |
074037ec RW |
471 | * wakup_source_deactivate - Mark given wakeup source as inactive. |
472 | * @ws: Wakeup source to handle. | |
c125e96f | 473 | * |
074037ec RW |
474 | * Update the @ws' statistics and notify the PM core that the wakeup source has |
475 | * become inactive by decrementing the counter of wakeup events being processed | |
476 | * and incrementing the counter of registered wakeup events. | |
477 | */ | |
478 | static void wakeup_source_deactivate(struct wakeup_source *ws) | |
479 | { | |
6791e36c | 480 | unsigned int cnt, inpr, cec; |
074037ec RW |
481 | ktime_t duration; |
482 | ktime_t now; | |
483 | ||
484 | ws->relax_count++; | |
485 | /* | |
486 | * __pm_relax() may be called directly or from a timer function. | |
487 | * If it is called directly right after the timer function has been | |
488 | * started, but before the timer function calls __pm_relax(), it is | |
489 | * possible that __pm_stay_awake() will be called in the meantime and | |
490 | * will set ws->active. Then, ws->active may be cleared immediately | |
491 | * by the __pm_relax() called from the timer function, but in such a | |
492 | * case ws->relax_count will be different from ws->active_count. | |
493 | */ | |
494 | if (ws->relax_count != ws->active_count) { | |
495 | ws->relax_count--; | |
496 | return; | |
497 | } | |
498 | ||
499 | ws->active = false; | |
500 | ||
501 | now = ktime_get(); | |
502 | duration = ktime_sub(now, ws->last_time); | |
503 | ws->total_time = ktime_add(ws->total_time, duration); | |
504 | if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) | |
505 | ws->max_time = duration; | |
506 | ||
30e3ce6d | 507 | ws->last_time = now; |
074037ec | 508 | del_timer(&ws->timer); |
da863cdd | 509 | ws->timer_expires = 0; |
074037ec | 510 | |
55850945 RW |
511 | if (ws->autosleep_enabled) |
512 | update_prevent_sleep_time(ws, now); | |
513 | ||
074037ec | 514 | /* |
023d3779 RW |
515 | * Increment the counter of registered wakeup events and decrement the |
516 | * couter of wakeup events in progress simultaneously. | |
074037ec | 517 | */ |
6791e36c AH |
518 | cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count); |
519 | trace_wakeup_source_deactivate(ws->name, cec); | |
60af1066 RW |
520 | |
521 | split_counters(&cnt, &inpr); | |
522 | if (!inpr && waitqueue_active(&wakeup_count_wait_queue)) | |
523 | wake_up(&wakeup_count_wait_queue); | |
074037ec RW |
524 | } |
525 | ||
526 | /** | |
527 | * __pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
528 | * @ws: Wakeup source object associated with the source of the event. | |
c125e96f RW |
529 | * |
530 | * Call this function for wakeup events whose processing started with calling | |
074037ec | 531 | * __pm_stay_awake(). |
c125e96f RW |
532 | * |
533 | * It is safe to call it from interrupt context. | |
534 | */ | |
074037ec | 535 | void __pm_relax(struct wakeup_source *ws) |
c125e96f RW |
536 | { |
537 | unsigned long flags; | |
538 | ||
074037ec RW |
539 | if (!ws) |
540 | return; | |
541 | ||
542 | spin_lock_irqsave(&ws->lock, flags); | |
543 | if (ws->active) | |
544 | wakeup_source_deactivate(ws); | |
545 | spin_unlock_irqrestore(&ws->lock, flags); | |
546 | } | |
547 | EXPORT_SYMBOL_GPL(__pm_relax); | |
548 | ||
549 | /** | |
550 | * pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
551 | * @dev: Device that signaled the event. | |
552 | * | |
553 | * Execute __pm_relax() for the @dev's wakeup source object. | |
554 | */ | |
555 | void pm_relax(struct device *dev) | |
556 | { | |
557 | unsigned long flags; | |
558 | ||
559 | if (!dev) | |
560 | return; | |
561 | ||
562 | spin_lock_irqsave(&dev->power.lock, flags); | |
563 | __pm_relax(dev->power.wakeup); | |
564 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 565 | } |
074037ec | 566 | EXPORT_SYMBOL_GPL(pm_relax); |
c125e96f RW |
567 | |
568 | /** | |
4eb241e5 | 569 | * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. |
074037ec | 570 | * @data: Address of the wakeup source object associated with the event source. |
c125e96f | 571 | * |
da863cdd RW |
572 | * Call wakeup_source_deactivate() for the wakeup source whose address is stored |
573 | * in @data if it is currently active and its timer has not been canceled and | |
574 | * the expiration time of the timer is not in future. | |
c125e96f | 575 | */ |
4eb241e5 | 576 | static void pm_wakeup_timer_fn(unsigned long data) |
074037ec | 577 | { |
da863cdd RW |
578 | struct wakeup_source *ws = (struct wakeup_source *)data; |
579 | unsigned long flags; | |
580 | ||
581 | spin_lock_irqsave(&ws->lock, flags); | |
582 | ||
583 | if (ws->active && ws->timer_expires | |
30e3ce6d | 584 | && time_after_eq(jiffies, ws->timer_expires)) { |
da863cdd | 585 | wakeup_source_deactivate(ws); |
30e3ce6d RW |
586 | ws->expire_count++; |
587 | } | |
da863cdd RW |
588 | |
589 | spin_unlock_irqrestore(&ws->lock, flags); | |
074037ec RW |
590 | } |
591 | ||
592 | /** | |
593 | * __pm_wakeup_event - Notify the PM core of a wakeup event. | |
594 | * @ws: Wakeup source object associated with the event source. | |
595 | * @msec: Anticipated event processing time (in milliseconds). | |
596 | * | |
597 | * Notify the PM core of a wakeup event whose source is @ws that will take | |
598 | * approximately @msec milliseconds to be processed by the kernel. If @ws is | |
599 | * not active, activate it. If @msec is nonzero, set up the @ws' timer to | |
600 | * execute pm_wakeup_timer_fn() in future. | |
601 | * | |
602 | * It is safe to call this function from interrupt context. | |
603 | */ | |
604 | void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) | |
c125e96f | 605 | { |
4eb241e5 | 606 | unsigned long flags; |
074037ec | 607 | unsigned long expires; |
c125e96f | 608 | |
074037ec RW |
609 | if (!ws) |
610 | return; | |
611 | ||
612 | spin_lock_irqsave(&ws->lock, flags); | |
613 | ||
30e3ce6d | 614 | wakeup_source_report_event(ws); |
074037ec RW |
615 | |
616 | if (!msec) { | |
617 | wakeup_source_deactivate(ws); | |
618 | goto unlock; | |
4eb241e5 | 619 | } |
074037ec RW |
620 | |
621 | expires = jiffies + msecs_to_jiffies(msec); | |
622 | if (!expires) | |
623 | expires = 1; | |
624 | ||
4782e165 | 625 | if (!ws->timer_expires || time_after(expires, ws->timer_expires)) { |
074037ec RW |
626 | mod_timer(&ws->timer, expires); |
627 | ws->timer_expires = expires; | |
628 | } | |
629 | ||
630 | unlock: | |
631 | spin_unlock_irqrestore(&ws->lock, flags); | |
c125e96f | 632 | } |
074037ec RW |
633 | EXPORT_SYMBOL_GPL(__pm_wakeup_event); |
634 | ||
c125e96f RW |
635 | |
636 | /** | |
637 | * pm_wakeup_event - Notify the PM core of a wakeup event. | |
638 | * @dev: Device the wakeup event is related to. | |
639 | * @msec: Anticipated event processing time (in milliseconds). | |
640 | * | |
074037ec | 641 | * Call __pm_wakeup_event() for the @dev's wakeup source object. |
c125e96f RW |
642 | */ |
643 | void pm_wakeup_event(struct device *dev, unsigned int msec) | |
644 | { | |
645 | unsigned long flags; | |
c125e96f | 646 | |
074037ec RW |
647 | if (!dev) |
648 | return; | |
c125e96f | 649 | |
074037ec RW |
650 | spin_lock_irqsave(&dev->power.lock, flags); |
651 | __pm_wakeup_event(dev->power.wakeup, msec); | |
652 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
653 | } | |
654 | EXPORT_SYMBOL_GPL(pm_wakeup_event); | |
4eb241e5 | 655 | |
a938da06 TP |
656 | static void print_active_wakeup_sources(void) |
657 | { | |
658 | struct wakeup_source *ws; | |
659 | int active = 0; | |
660 | struct wakeup_source *last_activity_ws = NULL; | |
661 | ||
662 | rcu_read_lock(); | |
663 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) { | |
664 | if (ws->active) { | |
665 | pr_info("active wakeup source: %s\n", ws->name); | |
666 | active = 1; | |
667 | } else if (!active && | |
668 | (!last_activity_ws || | |
669 | ktime_to_ns(ws->last_time) > | |
670 | ktime_to_ns(last_activity_ws->last_time))) { | |
671 | last_activity_ws = ws; | |
672 | } | |
673 | } | |
674 | ||
675 | if (!active && last_activity_ws) | |
676 | pr_info("last active wakeup source: %s\n", | |
677 | last_activity_ws->name); | |
678 | rcu_read_unlock(); | |
679 | } | |
680 | ||
c125e96f | 681 | /** |
a2867e08 | 682 | * pm_wakeup_pending - Check if power transition in progress should be aborted. |
c125e96f RW |
683 | * |
684 | * Compare the current number of registered wakeup events with its preserved | |
a2867e08 RW |
685 | * value from the past and return true if new wakeup events have been registered |
686 | * since the old value was stored. Also return true if the current number of | |
687 | * wakeup events being processed is different from zero. | |
c125e96f | 688 | */ |
a2867e08 | 689 | bool pm_wakeup_pending(void) |
c125e96f RW |
690 | { |
691 | unsigned long flags; | |
a2867e08 | 692 | bool ret = false; |
c125e96f RW |
693 | |
694 | spin_lock_irqsave(&events_lock, flags); | |
695 | if (events_check_enabled) { | |
023d3779 RW |
696 | unsigned int cnt, inpr; |
697 | ||
698 | split_counters(&cnt, &inpr); | |
699 | ret = (cnt != saved_count || inpr > 0); | |
a2867e08 | 700 | events_check_enabled = !ret; |
c125e96f RW |
701 | } |
702 | spin_unlock_irqrestore(&events_lock, flags); | |
a938da06 TP |
703 | |
704 | if (ret) | |
705 | print_active_wakeup_sources(); | |
706 | ||
c125e96f RW |
707 | return ret; |
708 | } | |
709 | ||
710 | /** | |
711 | * pm_get_wakeup_count - Read the number of registered wakeup events. | |
712 | * @count: Address to store the value at. | |
7483b4a4 | 713 | * @block: Whether or not to block. |
c125e96f | 714 | * |
7483b4a4 RW |
715 | * Store the number of registered wakeup events at the address in @count. If |
716 | * @block is set, block until the current number of wakeup events being | |
717 | * processed is zero. | |
c125e96f | 718 | * |
7483b4a4 RW |
719 | * Return 'false' if the current number of wakeup events being processed is |
720 | * nonzero. Otherwise return 'true'. | |
c125e96f | 721 | */ |
7483b4a4 | 722 | bool pm_get_wakeup_count(unsigned int *count, bool block) |
c125e96f | 723 | { |
023d3779 | 724 | unsigned int cnt, inpr; |
c125e96f | 725 | |
7483b4a4 RW |
726 | if (block) { |
727 | DEFINE_WAIT(wait); | |
728 | ||
729 | for (;;) { | |
730 | prepare_to_wait(&wakeup_count_wait_queue, &wait, | |
731 | TASK_INTERRUPTIBLE); | |
732 | split_counters(&cnt, &inpr); | |
733 | if (inpr == 0 || signal_pending(current)) | |
734 | break; | |
60af1066 | 735 | |
7483b4a4 RW |
736 | schedule(); |
737 | } | |
738 | finish_wait(&wakeup_count_wait_queue, &wait); | |
c125e96f | 739 | } |
074037ec | 740 | |
023d3779 RW |
741 | split_counters(&cnt, &inpr); |
742 | *count = cnt; | |
743 | return !inpr; | |
c125e96f RW |
744 | } |
745 | ||
746 | /** | |
747 | * pm_save_wakeup_count - Save the current number of registered wakeup events. | |
748 | * @count: Value to compare with the current number of registered wakeup events. | |
749 | * | |
750 | * If @count is equal to the current number of registered wakeup events and the | |
751 | * current number of wakeup events being processed is zero, store @count as the | |
378eef99 RW |
752 | * old number of registered wakeup events for pm_check_wakeup_events(), enable |
753 | * wakeup events detection and return 'true'. Otherwise disable wakeup events | |
754 | * detection and return 'false'. | |
c125e96f | 755 | */ |
074037ec | 756 | bool pm_save_wakeup_count(unsigned int count) |
c125e96f | 757 | { |
023d3779 | 758 | unsigned int cnt, inpr; |
49550709 | 759 | unsigned long flags; |
c125e96f | 760 | |
378eef99 | 761 | events_check_enabled = false; |
49550709 | 762 | spin_lock_irqsave(&events_lock, flags); |
023d3779 RW |
763 | split_counters(&cnt, &inpr); |
764 | if (cnt == count && inpr == 0) { | |
074037ec | 765 | saved_count = count; |
c125e96f | 766 | events_check_enabled = true; |
c125e96f | 767 | } |
49550709 | 768 | spin_unlock_irqrestore(&events_lock, flags); |
378eef99 | 769 | return events_check_enabled; |
c125e96f | 770 | } |
9c034392 | 771 | |
55850945 RW |
772 | #ifdef CONFIG_PM_AUTOSLEEP |
773 | /** | |
774 | * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources. | |
775 | * @enabled: Whether to set or to clear the autosleep_enabled flags. | |
776 | */ | |
777 | void pm_wakep_autosleep_enabled(bool set) | |
778 | { | |
779 | struct wakeup_source *ws; | |
780 | ktime_t now = ktime_get(); | |
781 | ||
782 | rcu_read_lock(); | |
783 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) { | |
784 | spin_lock_irq(&ws->lock); | |
785 | if (ws->autosleep_enabled != set) { | |
786 | ws->autosleep_enabled = set; | |
787 | if (ws->active) { | |
788 | if (set) | |
789 | ws->start_prevent_time = now; | |
790 | else | |
791 | update_prevent_sleep_time(ws, now); | |
792 | } | |
793 | } | |
794 | spin_unlock_irq(&ws->lock); | |
795 | } | |
796 | rcu_read_unlock(); | |
797 | } | |
798 | #endif /* CONFIG_PM_AUTOSLEEP */ | |
799 | ||
9c034392 RW |
800 | static struct dentry *wakeup_sources_stats_dentry; |
801 | ||
802 | /** | |
803 | * print_wakeup_source_stats - Print wakeup source statistics information. | |
804 | * @m: seq_file to print the statistics into. | |
805 | * @ws: Wakeup source object to print the statistics for. | |
806 | */ | |
807 | static int print_wakeup_source_stats(struct seq_file *m, | |
808 | struct wakeup_source *ws) | |
809 | { | |
810 | unsigned long flags; | |
811 | ktime_t total_time; | |
812 | ktime_t max_time; | |
813 | unsigned long active_count; | |
814 | ktime_t active_time; | |
55850945 | 815 | ktime_t prevent_sleep_time; |
9c034392 RW |
816 | int ret; |
817 | ||
818 | spin_lock_irqsave(&ws->lock, flags); | |
819 | ||
820 | total_time = ws->total_time; | |
821 | max_time = ws->max_time; | |
55850945 | 822 | prevent_sleep_time = ws->prevent_sleep_time; |
9c034392 RW |
823 | active_count = ws->active_count; |
824 | if (ws->active) { | |
55850945 RW |
825 | ktime_t now = ktime_get(); |
826 | ||
827 | active_time = ktime_sub(now, ws->last_time); | |
9c034392 RW |
828 | total_time = ktime_add(total_time, active_time); |
829 | if (active_time.tv64 > max_time.tv64) | |
830 | max_time = active_time; | |
55850945 RW |
831 | |
832 | if (ws->autosleep_enabled) | |
833 | prevent_sleep_time = ktime_add(prevent_sleep_time, | |
834 | ktime_sub(now, ws->start_prevent_time)); | |
9c034392 RW |
835 | } else { |
836 | active_time = ktime_set(0, 0); | |
837 | } | |
838 | ||
30e3ce6d | 839 | ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t" |
55850945 | 840 | "%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n", |
30e3ce6d RW |
841 | ws->name, active_count, ws->event_count, |
842 | ws->wakeup_count, ws->expire_count, | |
9c034392 | 843 | ktime_to_ms(active_time), ktime_to_ms(total_time), |
55850945 RW |
844 | ktime_to_ms(max_time), ktime_to_ms(ws->last_time), |
845 | ktime_to_ms(prevent_sleep_time)); | |
9c034392 RW |
846 | |
847 | spin_unlock_irqrestore(&ws->lock, flags); | |
848 | ||
849 | return ret; | |
850 | } | |
851 | ||
852 | /** | |
853 | * wakeup_sources_stats_show - Print wakeup sources statistics information. | |
854 | * @m: seq_file to print the statistics into. | |
855 | */ | |
856 | static int wakeup_sources_stats_show(struct seq_file *m, void *unused) | |
857 | { | |
858 | struct wakeup_source *ws; | |
859 | ||
30e3ce6d RW |
860 | seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t" |
861 | "expire_count\tactive_since\ttotal_time\tmax_time\t" | |
55850945 | 862 | "last_change\tprevent_suspend_time\n"); |
9c034392 RW |
863 | |
864 | rcu_read_lock(); | |
865 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) | |
866 | print_wakeup_source_stats(m, ws); | |
867 | rcu_read_unlock(); | |
868 | ||
869 | return 0; | |
870 | } | |
871 | ||
872 | static int wakeup_sources_stats_open(struct inode *inode, struct file *file) | |
873 | { | |
874 | return single_open(file, wakeup_sources_stats_show, NULL); | |
875 | } | |
876 | ||
877 | static const struct file_operations wakeup_sources_stats_fops = { | |
878 | .owner = THIS_MODULE, | |
879 | .open = wakeup_sources_stats_open, | |
880 | .read = seq_read, | |
881 | .llseek = seq_lseek, | |
882 | .release = single_release, | |
883 | }; | |
884 | ||
885 | static int __init wakeup_sources_debugfs_init(void) | |
886 | { | |
887 | wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources", | |
888 | S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops); | |
889 | return 0; | |
890 | } | |
891 | ||
892 | postcore_initcall(wakeup_sources_debugfs_init); |