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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 | { | |
130 | if (WARN_ON(!ws)) | |
131 | return; | |
132 | ||
7c95149b | 133 | spin_lock_init(&ws->lock); |
074037ec RW |
134 | setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws); |
135 | ws->active = false; | |
136 | ||
137 | spin_lock_irq(&events_lock); | |
138 | list_add_rcu(&ws->entry, &wakeup_sources); | |
139 | spin_unlock_irq(&events_lock); | |
074037ec RW |
140 | } |
141 | EXPORT_SYMBOL_GPL(wakeup_source_add); | |
142 | ||
143 | /** | |
144 | * wakeup_source_remove - Remove given object from the wakeup sources list. | |
145 | * @ws: Wakeup source object to remove from the list. | |
146 | */ | |
147 | void wakeup_source_remove(struct wakeup_source *ws) | |
148 | { | |
149 | if (WARN_ON(!ws)) | |
150 | return; | |
151 | ||
152 | spin_lock_irq(&events_lock); | |
153 | list_del_rcu(&ws->entry); | |
154 | spin_unlock_irq(&events_lock); | |
155 | synchronize_rcu(); | |
156 | } | |
157 | EXPORT_SYMBOL_GPL(wakeup_source_remove); | |
158 | ||
159 | /** | |
160 | * wakeup_source_register - Create wakeup source and add it to the list. | |
161 | * @name: Name of the wakeup source to register. | |
162 | */ | |
163 | struct wakeup_source *wakeup_source_register(const char *name) | |
164 | { | |
165 | struct wakeup_source *ws; | |
166 | ||
167 | ws = wakeup_source_create(name); | |
168 | if (ws) | |
169 | wakeup_source_add(ws); | |
170 | ||
171 | return ws; | |
172 | } | |
173 | EXPORT_SYMBOL_GPL(wakeup_source_register); | |
174 | ||
175 | /** | |
176 | * wakeup_source_unregister - Remove wakeup source from the list and remove it. | |
177 | * @ws: Wakeup source object to unregister. | |
178 | */ | |
179 | void wakeup_source_unregister(struct wakeup_source *ws) | |
180 | { | |
8671bbc1 RW |
181 | if (ws) { |
182 | wakeup_source_remove(ws); | |
183 | wakeup_source_destroy(ws); | |
184 | } | |
074037ec RW |
185 | } |
186 | EXPORT_SYMBOL_GPL(wakeup_source_unregister); | |
187 | ||
188 | /** | |
189 | * device_wakeup_attach - Attach a wakeup source object to a device object. | |
190 | * @dev: Device to handle. | |
191 | * @ws: Wakeup source object to attach to @dev. | |
192 | * | |
193 | * This causes @dev to be treated as a wakeup device. | |
194 | */ | |
195 | static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) | |
196 | { | |
197 | spin_lock_irq(&dev->power.lock); | |
198 | if (dev->power.wakeup) { | |
199 | spin_unlock_irq(&dev->power.lock); | |
200 | return -EEXIST; | |
201 | } | |
202 | dev->power.wakeup = ws; | |
203 | spin_unlock_irq(&dev->power.lock); | |
204 | return 0; | |
205 | } | |
206 | ||
207 | /** | |
208 | * device_wakeup_enable - Enable given device to be a wakeup source. | |
209 | * @dev: Device to handle. | |
210 | * | |
211 | * Create a wakeup source object, register it and attach it to @dev. | |
212 | */ | |
213 | int device_wakeup_enable(struct device *dev) | |
214 | { | |
215 | struct wakeup_source *ws; | |
216 | int ret; | |
217 | ||
218 | if (!dev || !dev->power.can_wakeup) | |
219 | return -EINVAL; | |
220 | ||
221 | ws = wakeup_source_register(dev_name(dev)); | |
222 | if (!ws) | |
223 | return -ENOMEM; | |
224 | ||
225 | ret = device_wakeup_attach(dev, ws); | |
226 | if (ret) | |
227 | wakeup_source_unregister(ws); | |
228 | ||
229 | return ret; | |
230 | } | |
231 | EXPORT_SYMBOL_GPL(device_wakeup_enable); | |
232 | ||
233 | /** | |
234 | * device_wakeup_detach - Detach a device's wakeup source object from it. | |
235 | * @dev: Device to detach the wakeup source object from. | |
236 | * | |
237 | * After it returns, @dev will not be treated as a wakeup device any more. | |
238 | */ | |
239 | static struct wakeup_source *device_wakeup_detach(struct device *dev) | |
240 | { | |
241 | struct wakeup_source *ws; | |
242 | ||
243 | spin_lock_irq(&dev->power.lock); | |
244 | ws = dev->power.wakeup; | |
245 | dev->power.wakeup = NULL; | |
246 | spin_unlock_irq(&dev->power.lock); | |
247 | return ws; | |
248 | } | |
249 | ||
250 | /** | |
251 | * device_wakeup_disable - Do not regard a device as a wakeup source any more. | |
252 | * @dev: Device to handle. | |
253 | * | |
254 | * Detach the @dev's wakeup source object from it, unregister this wakeup source | |
255 | * object and destroy it. | |
256 | */ | |
257 | int device_wakeup_disable(struct device *dev) | |
258 | { | |
259 | struct wakeup_source *ws; | |
260 | ||
261 | if (!dev || !dev->power.can_wakeup) | |
262 | return -EINVAL; | |
263 | ||
264 | ws = device_wakeup_detach(dev); | |
265 | if (ws) | |
266 | wakeup_source_unregister(ws); | |
267 | ||
268 | return 0; | |
269 | } | |
270 | EXPORT_SYMBOL_GPL(device_wakeup_disable); | |
271 | ||
cb8f51bd RW |
272 | /** |
273 | * device_set_wakeup_capable - Set/reset device wakeup capability flag. | |
274 | * @dev: Device to handle. | |
275 | * @capable: Whether or not @dev is capable of waking up the system from sleep. | |
276 | * | |
277 | * If @capable is set, set the @dev's power.can_wakeup flag and add its | |
278 | * wakeup-related attributes to sysfs. Otherwise, unset the @dev's | |
279 | * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. | |
280 | * | |
281 | * This function may sleep and it can't be called from any context where | |
282 | * sleeping is not allowed. | |
283 | */ | |
284 | void device_set_wakeup_capable(struct device *dev, bool capable) | |
285 | { | |
286 | if (!!dev->power.can_wakeup == !!capable) | |
287 | return; | |
288 | ||
22110faf | 289 | if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { |
cb8f51bd RW |
290 | if (capable) { |
291 | if (wakeup_sysfs_add(dev)) | |
292 | return; | |
293 | } else { | |
294 | wakeup_sysfs_remove(dev); | |
295 | } | |
296 | } | |
297 | dev->power.can_wakeup = capable; | |
298 | } | |
299 | EXPORT_SYMBOL_GPL(device_set_wakeup_capable); | |
300 | ||
074037ec RW |
301 | /** |
302 | * device_init_wakeup - Device wakeup initialization. | |
303 | * @dev: Device to handle. | |
304 | * @enable: Whether or not to enable @dev as a wakeup device. | |
305 | * | |
306 | * By default, most devices should leave wakeup disabled. The exceptions are | |
307 | * devices that everyone expects to be wakeup sources: keyboards, power buttons, | |
8f88893c AS |
308 | * possibly network interfaces, etc. Also, devices that don't generate their |
309 | * own wakeup requests but merely forward requests from one bus to another | |
310 | * (like PCI bridges) should have wakeup enabled by default. | |
074037ec RW |
311 | */ |
312 | int device_init_wakeup(struct device *dev, bool enable) | |
313 | { | |
314 | int ret = 0; | |
315 | ||
316 | if (enable) { | |
317 | device_set_wakeup_capable(dev, true); | |
318 | ret = device_wakeup_enable(dev); | |
319 | } else { | |
320 | device_set_wakeup_capable(dev, false); | |
321 | } | |
322 | ||
323 | return ret; | |
324 | } | |
325 | EXPORT_SYMBOL_GPL(device_init_wakeup); | |
326 | ||
327 | /** | |
328 | * device_set_wakeup_enable - Enable or disable a device to wake up the system. | |
329 | * @dev: Device to handle. | |
330 | */ | |
331 | int device_set_wakeup_enable(struct device *dev, bool enable) | |
332 | { | |
333 | if (!dev || !dev->power.can_wakeup) | |
334 | return -EINVAL; | |
335 | ||
336 | return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev); | |
337 | } | |
338 | EXPORT_SYMBOL_GPL(device_set_wakeup_enable); | |
4eb241e5 | 339 | |
c125e96f RW |
340 | /* |
341 | * The functions below use the observation that each wakeup event starts a | |
342 | * period in which the system should not be suspended. The moment this period | |
343 | * will end depends on how the wakeup event is going to be processed after being | |
344 | * detected and all of the possible cases can be divided into two distinct | |
345 | * groups. | |
346 | * | |
347 | * First, a wakeup event may be detected by the same functional unit that will | |
348 | * carry out the entire processing of it and possibly will pass it to user space | |
349 | * for further processing. In that case the functional unit that has detected | |
350 | * the event may later "close" the "no suspend" period associated with it | |
351 | * directly as soon as it has been dealt with. The pair of pm_stay_awake() and | |
352 | * pm_relax(), balanced with each other, is supposed to be used in such | |
353 | * situations. | |
354 | * | |
355 | * Second, a wakeup event may be detected by one functional unit and processed | |
356 | * by another one. In that case the unit that has detected it cannot really | |
357 | * "close" the "no suspend" period associated with it, unless it knows in | |
358 | * advance what's going to happen to the event during processing. This | |
359 | * knowledge, however, may not be available to it, so it can simply specify time | |
360 | * to wait before the system can be suspended and pass it as the second | |
361 | * argument of pm_wakeup_event(). | |
074037ec RW |
362 | * |
363 | * It is valid to call pm_relax() after pm_wakeup_event(), in which case the | |
364 | * "no suspend" period will be ended either by the pm_relax(), or by the timer | |
365 | * function executed when the timer expires, whichever comes first. | |
c125e96f RW |
366 | */ |
367 | ||
074037ec RW |
368 | /** |
369 | * wakup_source_activate - Mark given wakeup source as active. | |
370 | * @ws: Wakeup source to handle. | |
371 | * | |
372 | * Update the @ws' statistics and, if @ws has just been activated, notify the PM | |
373 | * core of the event by incrementing the counter of of wakeup events being | |
374 | * processed. | |
375 | */ | |
376 | static void wakeup_source_activate(struct wakeup_source *ws) | |
377 | { | |
6791e36c AH |
378 | unsigned int cec; |
379 | ||
074037ec RW |
380 | ws->active = true; |
381 | ws->active_count++; | |
074037ec RW |
382 | ws->last_time = ktime_get(); |
383 | ||
023d3779 | 384 | /* Increment the counter of events in progress. */ |
6791e36c AH |
385 | cec = atomic_inc_return(&combined_event_count); |
386 | ||
387 | trace_wakeup_source_activate(ws->name, cec); | |
074037ec RW |
388 | } |
389 | ||
30e3ce6d RW |
390 | /** |
391 | * wakeup_source_report_event - Report wakeup event using the given source. | |
392 | * @ws: Wakeup source to report the event for. | |
393 | */ | |
394 | static void wakeup_source_report_event(struct wakeup_source *ws) | |
395 | { | |
396 | ws->event_count++; | |
397 | /* This is racy, but the counter is approximate anyway. */ | |
398 | if (events_check_enabled) | |
399 | ws->wakeup_count++; | |
400 | ||
401 | if (!ws->active) | |
402 | wakeup_source_activate(ws); | |
403 | } | |
404 | ||
074037ec RW |
405 | /** |
406 | * __pm_stay_awake - Notify the PM core of a wakeup event. | |
407 | * @ws: Wakeup source object associated with the source of the event. | |
408 | * | |
409 | * It is safe to call this function from interrupt context. | |
410 | */ | |
411 | void __pm_stay_awake(struct wakeup_source *ws) | |
412 | { | |
413 | unsigned long flags; | |
414 | ||
415 | if (!ws) | |
416 | return; | |
417 | ||
418 | spin_lock_irqsave(&ws->lock, flags); | |
4782e165 | 419 | |
30e3ce6d | 420 | wakeup_source_report_event(ws); |
4782e165 RW |
421 | del_timer(&ws->timer); |
422 | ws->timer_expires = 0; | |
423 | ||
074037ec RW |
424 | spin_unlock_irqrestore(&ws->lock, flags); |
425 | } | |
426 | EXPORT_SYMBOL_GPL(__pm_stay_awake); | |
427 | ||
c125e96f RW |
428 | /** |
429 | * pm_stay_awake - Notify the PM core that a wakeup event is being processed. | |
430 | * @dev: Device the wakeup event is related to. | |
431 | * | |
074037ec RW |
432 | * Notify the PM core of a wakeup event (signaled by @dev) by calling |
433 | * __pm_stay_awake for the @dev's wakeup source object. | |
c125e96f RW |
434 | * |
435 | * Call this function after detecting of a wakeup event if pm_relax() is going | |
436 | * to be called directly after processing the event (and possibly passing it to | |
437 | * user space for further processing). | |
c125e96f RW |
438 | */ |
439 | void pm_stay_awake(struct device *dev) | |
440 | { | |
441 | unsigned long flags; | |
442 | ||
074037ec RW |
443 | if (!dev) |
444 | return; | |
c125e96f | 445 | |
074037ec RW |
446 | spin_lock_irqsave(&dev->power.lock, flags); |
447 | __pm_stay_awake(dev->power.wakeup); | |
448 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 449 | } |
074037ec | 450 | EXPORT_SYMBOL_GPL(pm_stay_awake); |
c125e96f RW |
451 | |
452 | /** | |
074037ec RW |
453 | * wakup_source_deactivate - Mark given wakeup source as inactive. |
454 | * @ws: Wakeup source to handle. | |
c125e96f | 455 | * |
074037ec RW |
456 | * Update the @ws' statistics and notify the PM core that the wakeup source has |
457 | * become inactive by decrementing the counter of wakeup events being processed | |
458 | * and incrementing the counter of registered wakeup events. | |
459 | */ | |
460 | static void wakeup_source_deactivate(struct wakeup_source *ws) | |
461 | { | |
6791e36c | 462 | unsigned int cnt, inpr, cec; |
074037ec RW |
463 | ktime_t duration; |
464 | ktime_t now; | |
465 | ||
466 | ws->relax_count++; | |
467 | /* | |
468 | * __pm_relax() may be called directly or from a timer function. | |
469 | * If it is called directly right after the timer function has been | |
470 | * started, but before the timer function calls __pm_relax(), it is | |
471 | * possible that __pm_stay_awake() will be called in the meantime and | |
472 | * will set ws->active. Then, ws->active may be cleared immediately | |
473 | * by the __pm_relax() called from the timer function, but in such a | |
474 | * case ws->relax_count will be different from ws->active_count. | |
475 | */ | |
476 | if (ws->relax_count != ws->active_count) { | |
477 | ws->relax_count--; | |
478 | return; | |
479 | } | |
480 | ||
481 | ws->active = false; | |
482 | ||
483 | now = ktime_get(); | |
484 | duration = ktime_sub(now, ws->last_time); | |
485 | ws->total_time = ktime_add(ws->total_time, duration); | |
486 | if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) | |
487 | ws->max_time = duration; | |
488 | ||
30e3ce6d | 489 | ws->last_time = now; |
074037ec | 490 | del_timer(&ws->timer); |
da863cdd | 491 | ws->timer_expires = 0; |
074037ec RW |
492 | |
493 | /* | |
023d3779 RW |
494 | * Increment the counter of registered wakeup events and decrement the |
495 | * couter of wakeup events in progress simultaneously. | |
074037ec | 496 | */ |
6791e36c AH |
497 | cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count); |
498 | trace_wakeup_source_deactivate(ws->name, cec); | |
60af1066 RW |
499 | |
500 | split_counters(&cnt, &inpr); | |
501 | if (!inpr && waitqueue_active(&wakeup_count_wait_queue)) | |
502 | wake_up(&wakeup_count_wait_queue); | |
074037ec RW |
503 | } |
504 | ||
505 | /** | |
506 | * __pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
507 | * @ws: Wakeup source object associated with the source of the event. | |
c125e96f RW |
508 | * |
509 | * Call this function for wakeup events whose processing started with calling | |
074037ec | 510 | * __pm_stay_awake(). |
c125e96f RW |
511 | * |
512 | * It is safe to call it from interrupt context. | |
513 | */ | |
074037ec | 514 | void __pm_relax(struct wakeup_source *ws) |
c125e96f RW |
515 | { |
516 | unsigned long flags; | |
517 | ||
074037ec RW |
518 | if (!ws) |
519 | return; | |
520 | ||
521 | spin_lock_irqsave(&ws->lock, flags); | |
522 | if (ws->active) | |
523 | wakeup_source_deactivate(ws); | |
524 | spin_unlock_irqrestore(&ws->lock, flags); | |
525 | } | |
526 | EXPORT_SYMBOL_GPL(__pm_relax); | |
527 | ||
528 | /** | |
529 | * pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
530 | * @dev: Device that signaled the event. | |
531 | * | |
532 | * Execute __pm_relax() for the @dev's wakeup source object. | |
533 | */ | |
534 | void pm_relax(struct device *dev) | |
535 | { | |
536 | unsigned long flags; | |
537 | ||
538 | if (!dev) | |
539 | return; | |
540 | ||
541 | spin_lock_irqsave(&dev->power.lock, flags); | |
542 | __pm_relax(dev->power.wakeup); | |
543 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 544 | } |
074037ec | 545 | EXPORT_SYMBOL_GPL(pm_relax); |
c125e96f RW |
546 | |
547 | /** | |
4eb241e5 | 548 | * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. |
074037ec | 549 | * @data: Address of the wakeup source object associated with the event source. |
c125e96f | 550 | * |
da863cdd RW |
551 | * Call wakeup_source_deactivate() for the wakeup source whose address is stored |
552 | * in @data if it is currently active and its timer has not been canceled and | |
553 | * the expiration time of the timer is not in future. | |
c125e96f | 554 | */ |
4eb241e5 | 555 | static void pm_wakeup_timer_fn(unsigned long data) |
074037ec | 556 | { |
da863cdd RW |
557 | struct wakeup_source *ws = (struct wakeup_source *)data; |
558 | unsigned long flags; | |
559 | ||
560 | spin_lock_irqsave(&ws->lock, flags); | |
561 | ||
562 | if (ws->active && ws->timer_expires | |
30e3ce6d | 563 | && time_after_eq(jiffies, ws->timer_expires)) { |
da863cdd | 564 | wakeup_source_deactivate(ws); |
30e3ce6d RW |
565 | ws->expire_count++; |
566 | } | |
da863cdd RW |
567 | |
568 | spin_unlock_irqrestore(&ws->lock, flags); | |
074037ec RW |
569 | } |
570 | ||
571 | /** | |
572 | * __pm_wakeup_event - Notify the PM core of a wakeup event. | |
573 | * @ws: Wakeup source object associated with the event source. | |
574 | * @msec: Anticipated event processing time (in milliseconds). | |
575 | * | |
576 | * Notify the PM core of a wakeup event whose source is @ws that will take | |
577 | * approximately @msec milliseconds to be processed by the kernel. If @ws is | |
578 | * not active, activate it. If @msec is nonzero, set up the @ws' timer to | |
579 | * execute pm_wakeup_timer_fn() in future. | |
580 | * | |
581 | * It is safe to call this function from interrupt context. | |
582 | */ | |
583 | void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) | |
c125e96f | 584 | { |
4eb241e5 | 585 | unsigned long flags; |
074037ec | 586 | unsigned long expires; |
c125e96f | 587 | |
074037ec RW |
588 | if (!ws) |
589 | return; | |
590 | ||
591 | spin_lock_irqsave(&ws->lock, flags); | |
592 | ||
30e3ce6d | 593 | wakeup_source_report_event(ws); |
074037ec RW |
594 | |
595 | if (!msec) { | |
596 | wakeup_source_deactivate(ws); | |
597 | goto unlock; | |
4eb241e5 | 598 | } |
074037ec RW |
599 | |
600 | expires = jiffies + msecs_to_jiffies(msec); | |
601 | if (!expires) | |
602 | expires = 1; | |
603 | ||
4782e165 | 604 | if (!ws->timer_expires || time_after(expires, ws->timer_expires)) { |
074037ec RW |
605 | mod_timer(&ws->timer, expires); |
606 | ws->timer_expires = expires; | |
607 | } | |
608 | ||
609 | unlock: | |
610 | spin_unlock_irqrestore(&ws->lock, flags); | |
c125e96f | 611 | } |
074037ec RW |
612 | EXPORT_SYMBOL_GPL(__pm_wakeup_event); |
613 | ||
c125e96f RW |
614 | |
615 | /** | |
616 | * pm_wakeup_event - Notify the PM core of a wakeup event. | |
617 | * @dev: Device the wakeup event is related to. | |
618 | * @msec: Anticipated event processing time (in milliseconds). | |
619 | * | |
074037ec | 620 | * Call __pm_wakeup_event() for the @dev's wakeup source object. |
c125e96f RW |
621 | */ |
622 | void pm_wakeup_event(struct device *dev, unsigned int msec) | |
623 | { | |
624 | unsigned long flags; | |
c125e96f | 625 | |
074037ec RW |
626 | if (!dev) |
627 | return; | |
c125e96f | 628 | |
074037ec RW |
629 | spin_lock_irqsave(&dev->power.lock, flags); |
630 | __pm_wakeup_event(dev->power.wakeup, msec); | |
631 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
632 | } | |
633 | EXPORT_SYMBOL_GPL(pm_wakeup_event); | |
4eb241e5 | 634 | |
c125e96f | 635 | /** |
a2867e08 | 636 | * pm_wakeup_pending - Check if power transition in progress should be aborted. |
c125e96f RW |
637 | * |
638 | * Compare the current number of registered wakeup events with its preserved | |
a2867e08 RW |
639 | * value from the past and return true if new wakeup events have been registered |
640 | * since the old value was stored. Also return true if the current number of | |
641 | * wakeup events being processed is different from zero. | |
c125e96f | 642 | */ |
a2867e08 | 643 | bool pm_wakeup_pending(void) |
c125e96f RW |
644 | { |
645 | unsigned long flags; | |
a2867e08 | 646 | bool ret = false; |
c125e96f RW |
647 | |
648 | spin_lock_irqsave(&events_lock, flags); | |
649 | if (events_check_enabled) { | |
023d3779 RW |
650 | unsigned int cnt, inpr; |
651 | ||
652 | split_counters(&cnt, &inpr); | |
653 | ret = (cnt != saved_count || inpr > 0); | |
a2867e08 | 654 | events_check_enabled = !ret; |
c125e96f RW |
655 | } |
656 | spin_unlock_irqrestore(&events_lock, flags); | |
657 | return ret; | |
658 | } | |
659 | ||
660 | /** | |
661 | * pm_get_wakeup_count - Read the number of registered wakeup events. | |
662 | * @count: Address to store the value at. | |
7483b4a4 | 663 | * @block: Whether or not to block. |
c125e96f | 664 | * |
7483b4a4 RW |
665 | * Store the number of registered wakeup events at the address in @count. If |
666 | * @block is set, block until the current number of wakeup events being | |
667 | * processed is zero. | |
c125e96f | 668 | * |
7483b4a4 RW |
669 | * Return 'false' if the current number of wakeup events being processed is |
670 | * nonzero. Otherwise return 'true'. | |
c125e96f | 671 | */ |
7483b4a4 | 672 | bool pm_get_wakeup_count(unsigned int *count, bool block) |
c125e96f | 673 | { |
023d3779 | 674 | unsigned int cnt, inpr; |
c125e96f | 675 | |
7483b4a4 RW |
676 | if (block) { |
677 | DEFINE_WAIT(wait); | |
678 | ||
679 | for (;;) { | |
680 | prepare_to_wait(&wakeup_count_wait_queue, &wait, | |
681 | TASK_INTERRUPTIBLE); | |
682 | split_counters(&cnt, &inpr); | |
683 | if (inpr == 0 || signal_pending(current)) | |
684 | break; | |
60af1066 | 685 | |
7483b4a4 RW |
686 | schedule(); |
687 | } | |
688 | finish_wait(&wakeup_count_wait_queue, &wait); | |
c125e96f | 689 | } |
074037ec | 690 | |
023d3779 RW |
691 | split_counters(&cnt, &inpr); |
692 | *count = cnt; | |
693 | return !inpr; | |
c125e96f RW |
694 | } |
695 | ||
696 | /** | |
697 | * pm_save_wakeup_count - Save the current number of registered wakeup events. | |
698 | * @count: Value to compare with the current number of registered wakeup events. | |
699 | * | |
700 | * If @count is equal to the current number of registered wakeup events and the | |
701 | * current number of wakeup events being processed is zero, store @count as the | |
378eef99 RW |
702 | * old number of registered wakeup events for pm_check_wakeup_events(), enable |
703 | * wakeup events detection and return 'true'. Otherwise disable wakeup events | |
704 | * detection and return 'false'. | |
c125e96f | 705 | */ |
074037ec | 706 | bool pm_save_wakeup_count(unsigned int count) |
c125e96f | 707 | { |
023d3779 | 708 | unsigned int cnt, inpr; |
c125e96f | 709 | |
378eef99 | 710 | events_check_enabled = false; |
c125e96f | 711 | spin_lock_irq(&events_lock); |
023d3779 RW |
712 | split_counters(&cnt, &inpr); |
713 | if (cnt == count && inpr == 0) { | |
074037ec | 714 | saved_count = count; |
c125e96f | 715 | events_check_enabled = true; |
c125e96f RW |
716 | } |
717 | spin_unlock_irq(&events_lock); | |
378eef99 | 718 | return events_check_enabled; |
c125e96f | 719 | } |
9c034392 RW |
720 | |
721 | static struct dentry *wakeup_sources_stats_dentry; | |
722 | ||
723 | /** | |
724 | * print_wakeup_source_stats - Print wakeup source statistics information. | |
725 | * @m: seq_file to print the statistics into. | |
726 | * @ws: Wakeup source object to print the statistics for. | |
727 | */ | |
728 | static int print_wakeup_source_stats(struct seq_file *m, | |
729 | struct wakeup_source *ws) | |
730 | { | |
731 | unsigned long flags; | |
732 | ktime_t total_time; | |
733 | ktime_t max_time; | |
734 | unsigned long active_count; | |
735 | ktime_t active_time; | |
736 | int ret; | |
737 | ||
738 | spin_lock_irqsave(&ws->lock, flags); | |
739 | ||
740 | total_time = ws->total_time; | |
741 | max_time = ws->max_time; | |
742 | active_count = ws->active_count; | |
743 | if (ws->active) { | |
744 | active_time = ktime_sub(ktime_get(), ws->last_time); | |
745 | total_time = ktime_add(total_time, active_time); | |
746 | if (active_time.tv64 > max_time.tv64) | |
747 | max_time = active_time; | |
748 | } else { | |
749 | active_time = ktime_set(0, 0); | |
750 | } | |
751 | ||
30e3ce6d | 752 | ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t" |
9c034392 | 753 | "%lld\t\t%lld\t\t%lld\t\t%lld\n", |
30e3ce6d RW |
754 | ws->name, active_count, ws->event_count, |
755 | ws->wakeup_count, ws->expire_count, | |
9c034392 RW |
756 | ktime_to_ms(active_time), ktime_to_ms(total_time), |
757 | ktime_to_ms(max_time), ktime_to_ms(ws->last_time)); | |
758 | ||
759 | spin_unlock_irqrestore(&ws->lock, flags); | |
760 | ||
761 | return ret; | |
762 | } | |
763 | ||
764 | /** | |
765 | * wakeup_sources_stats_show - Print wakeup sources statistics information. | |
766 | * @m: seq_file to print the statistics into. | |
767 | */ | |
768 | static int wakeup_sources_stats_show(struct seq_file *m, void *unused) | |
769 | { | |
770 | struct wakeup_source *ws; | |
771 | ||
30e3ce6d RW |
772 | seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t" |
773 | "expire_count\tactive_since\ttotal_time\tmax_time\t" | |
774 | "last_change\n"); | |
9c034392 RW |
775 | |
776 | rcu_read_lock(); | |
777 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) | |
778 | print_wakeup_source_stats(m, ws); | |
779 | rcu_read_unlock(); | |
780 | ||
781 | return 0; | |
782 | } | |
783 | ||
784 | static int wakeup_sources_stats_open(struct inode *inode, struct file *file) | |
785 | { | |
786 | return single_open(file, wakeup_sources_stats_show, NULL); | |
787 | } | |
788 | ||
789 | static const struct file_operations wakeup_sources_stats_fops = { | |
790 | .owner = THIS_MODULE, | |
791 | .open = wakeup_sources_stats_open, | |
792 | .read = seq_read, | |
793 | .llseek = seq_lseek, | |
794 | .release = single_release, | |
795 | }; | |
796 | ||
797 | static int __init wakeup_sources_debugfs_init(void) | |
798 | { | |
799 | wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources", | |
800 | S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops); | |
801 | return 0; | |
802 | } | |
803 | ||
804 | postcore_initcall(wakeup_sources_debugfs_init); |