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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> | |
13 | #include <linux/suspend.h> | |
9c034392 RW |
14 | #include <linux/seq_file.h> |
15 | #include <linux/debugfs.h> | |
074037ec RW |
16 | |
17 | #include "power.h" | |
18 | ||
19 | #define TIMEOUT 100 | |
c125e96f RW |
20 | |
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 | */ | |
25 | bool events_check_enabled; | |
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 | ||
54 | /** | |
55 | * wakeup_source_create - Create a struct wakeup_source object. | |
56 | * @name: Name of the new wakeup source. | |
57 | */ | |
58 | struct wakeup_source *wakeup_source_create(const char *name) | |
59 | { | |
60 | struct wakeup_source *ws; | |
61 | ||
62 | ws = kzalloc(sizeof(*ws), GFP_KERNEL); | |
63 | if (!ws) | |
64 | return NULL; | |
65 | ||
66 | spin_lock_init(&ws->lock); | |
67 | if (name) | |
68 | ws->name = kstrdup(name, GFP_KERNEL); | |
69 | ||
70 | return ws; | |
71 | } | |
72 | EXPORT_SYMBOL_GPL(wakeup_source_create); | |
73 | ||
74 | /** | |
75 | * wakeup_source_destroy - Destroy a struct wakeup_source object. | |
76 | * @ws: Wakeup source to destroy. | |
77 | */ | |
78 | void wakeup_source_destroy(struct wakeup_source *ws) | |
79 | { | |
80 | if (!ws) | |
81 | return; | |
82 | ||
83 | spin_lock_irq(&ws->lock); | |
84 | while (ws->active) { | |
85 | spin_unlock_irq(&ws->lock); | |
86 | ||
87 | schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT)); | |
88 | ||
89 | spin_lock_irq(&ws->lock); | |
90 | } | |
91 | spin_unlock_irq(&ws->lock); | |
92 | ||
93 | kfree(ws->name); | |
94 | kfree(ws); | |
95 | } | |
96 | EXPORT_SYMBOL_GPL(wakeup_source_destroy); | |
97 | ||
98 | /** | |
99 | * wakeup_source_add - Add given object to the list of wakeup sources. | |
100 | * @ws: Wakeup source object to add to the list. | |
101 | */ | |
102 | void wakeup_source_add(struct wakeup_source *ws) | |
103 | { | |
104 | if (WARN_ON(!ws)) | |
105 | return; | |
106 | ||
107 | setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws); | |
108 | ws->active = false; | |
109 | ||
110 | spin_lock_irq(&events_lock); | |
111 | list_add_rcu(&ws->entry, &wakeup_sources); | |
112 | spin_unlock_irq(&events_lock); | |
074037ec RW |
113 | } |
114 | EXPORT_SYMBOL_GPL(wakeup_source_add); | |
115 | ||
116 | /** | |
117 | * wakeup_source_remove - Remove given object from the wakeup sources list. | |
118 | * @ws: Wakeup source object to remove from the list. | |
119 | */ | |
120 | void wakeup_source_remove(struct wakeup_source *ws) | |
121 | { | |
122 | if (WARN_ON(!ws)) | |
123 | return; | |
124 | ||
125 | spin_lock_irq(&events_lock); | |
126 | list_del_rcu(&ws->entry); | |
127 | spin_unlock_irq(&events_lock); | |
128 | synchronize_rcu(); | |
129 | } | |
130 | EXPORT_SYMBOL_GPL(wakeup_source_remove); | |
131 | ||
132 | /** | |
133 | * wakeup_source_register - Create wakeup source and add it to the list. | |
134 | * @name: Name of the wakeup source to register. | |
135 | */ | |
136 | struct wakeup_source *wakeup_source_register(const char *name) | |
137 | { | |
138 | struct wakeup_source *ws; | |
139 | ||
140 | ws = wakeup_source_create(name); | |
141 | if (ws) | |
142 | wakeup_source_add(ws); | |
143 | ||
144 | return ws; | |
145 | } | |
146 | EXPORT_SYMBOL_GPL(wakeup_source_register); | |
147 | ||
148 | /** | |
149 | * wakeup_source_unregister - Remove wakeup source from the list and remove it. | |
150 | * @ws: Wakeup source object to unregister. | |
151 | */ | |
152 | void wakeup_source_unregister(struct wakeup_source *ws) | |
153 | { | |
154 | wakeup_source_remove(ws); | |
155 | wakeup_source_destroy(ws); | |
156 | } | |
157 | EXPORT_SYMBOL_GPL(wakeup_source_unregister); | |
158 | ||
159 | /** | |
160 | * device_wakeup_attach - Attach a wakeup source object to a device object. | |
161 | * @dev: Device to handle. | |
162 | * @ws: Wakeup source object to attach to @dev. | |
163 | * | |
164 | * This causes @dev to be treated as a wakeup device. | |
165 | */ | |
166 | static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) | |
167 | { | |
168 | spin_lock_irq(&dev->power.lock); | |
169 | if (dev->power.wakeup) { | |
170 | spin_unlock_irq(&dev->power.lock); | |
171 | return -EEXIST; | |
172 | } | |
173 | dev->power.wakeup = ws; | |
174 | spin_unlock_irq(&dev->power.lock); | |
175 | return 0; | |
176 | } | |
177 | ||
178 | /** | |
179 | * device_wakeup_enable - Enable given device to be a wakeup source. | |
180 | * @dev: Device to handle. | |
181 | * | |
182 | * Create a wakeup source object, register it and attach it to @dev. | |
183 | */ | |
184 | int device_wakeup_enable(struct device *dev) | |
185 | { | |
186 | struct wakeup_source *ws; | |
187 | int ret; | |
188 | ||
189 | if (!dev || !dev->power.can_wakeup) | |
190 | return -EINVAL; | |
191 | ||
192 | ws = wakeup_source_register(dev_name(dev)); | |
193 | if (!ws) | |
194 | return -ENOMEM; | |
195 | ||
196 | ret = device_wakeup_attach(dev, ws); | |
197 | if (ret) | |
198 | wakeup_source_unregister(ws); | |
199 | ||
200 | return ret; | |
201 | } | |
202 | EXPORT_SYMBOL_GPL(device_wakeup_enable); | |
203 | ||
204 | /** | |
205 | * device_wakeup_detach - Detach a device's wakeup source object from it. | |
206 | * @dev: Device to detach the wakeup source object from. | |
207 | * | |
208 | * After it returns, @dev will not be treated as a wakeup device any more. | |
209 | */ | |
210 | static struct wakeup_source *device_wakeup_detach(struct device *dev) | |
211 | { | |
212 | struct wakeup_source *ws; | |
213 | ||
214 | spin_lock_irq(&dev->power.lock); | |
215 | ws = dev->power.wakeup; | |
216 | dev->power.wakeup = NULL; | |
217 | spin_unlock_irq(&dev->power.lock); | |
218 | return ws; | |
219 | } | |
220 | ||
221 | /** | |
222 | * device_wakeup_disable - Do not regard a device as a wakeup source any more. | |
223 | * @dev: Device to handle. | |
224 | * | |
225 | * Detach the @dev's wakeup source object from it, unregister this wakeup source | |
226 | * object and destroy it. | |
227 | */ | |
228 | int device_wakeup_disable(struct device *dev) | |
229 | { | |
230 | struct wakeup_source *ws; | |
231 | ||
232 | if (!dev || !dev->power.can_wakeup) | |
233 | return -EINVAL; | |
234 | ||
235 | ws = device_wakeup_detach(dev); | |
236 | if (ws) | |
237 | wakeup_source_unregister(ws); | |
238 | ||
239 | return 0; | |
240 | } | |
241 | EXPORT_SYMBOL_GPL(device_wakeup_disable); | |
242 | ||
cb8f51bd RW |
243 | /** |
244 | * device_set_wakeup_capable - Set/reset device wakeup capability flag. | |
245 | * @dev: Device to handle. | |
246 | * @capable: Whether or not @dev is capable of waking up the system from sleep. | |
247 | * | |
248 | * If @capable is set, set the @dev's power.can_wakeup flag and add its | |
249 | * wakeup-related attributes to sysfs. Otherwise, unset the @dev's | |
250 | * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. | |
251 | * | |
252 | * This function may sleep and it can't be called from any context where | |
253 | * sleeping is not allowed. | |
254 | */ | |
255 | void device_set_wakeup_capable(struct device *dev, bool capable) | |
256 | { | |
257 | if (!!dev->power.can_wakeup == !!capable) | |
258 | return; | |
259 | ||
22110faf | 260 | if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { |
cb8f51bd RW |
261 | if (capable) { |
262 | if (wakeup_sysfs_add(dev)) | |
263 | return; | |
264 | } else { | |
265 | wakeup_sysfs_remove(dev); | |
266 | } | |
267 | } | |
268 | dev->power.can_wakeup = capable; | |
269 | } | |
270 | EXPORT_SYMBOL_GPL(device_set_wakeup_capable); | |
271 | ||
074037ec RW |
272 | /** |
273 | * device_init_wakeup - Device wakeup initialization. | |
274 | * @dev: Device to handle. | |
275 | * @enable: Whether or not to enable @dev as a wakeup device. | |
276 | * | |
277 | * By default, most devices should leave wakeup disabled. The exceptions are | |
278 | * devices that everyone expects to be wakeup sources: keyboards, power buttons, | |
8f88893c AS |
279 | * possibly network interfaces, etc. Also, devices that don't generate their |
280 | * own wakeup requests but merely forward requests from one bus to another | |
281 | * (like PCI bridges) should have wakeup enabled by default. | |
074037ec RW |
282 | */ |
283 | int device_init_wakeup(struct device *dev, bool enable) | |
284 | { | |
285 | int ret = 0; | |
286 | ||
287 | if (enable) { | |
288 | device_set_wakeup_capable(dev, true); | |
289 | ret = device_wakeup_enable(dev); | |
290 | } else { | |
291 | device_set_wakeup_capable(dev, false); | |
292 | } | |
293 | ||
294 | return ret; | |
295 | } | |
296 | EXPORT_SYMBOL_GPL(device_init_wakeup); | |
297 | ||
298 | /** | |
299 | * device_set_wakeup_enable - Enable or disable a device to wake up the system. | |
300 | * @dev: Device to handle. | |
301 | */ | |
302 | int device_set_wakeup_enable(struct device *dev, bool enable) | |
303 | { | |
304 | if (!dev || !dev->power.can_wakeup) | |
305 | return -EINVAL; | |
306 | ||
307 | return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev); | |
308 | } | |
309 | EXPORT_SYMBOL_GPL(device_set_wakeup_enable); | |
4eb241e5 | 310 | |
c125e96f RW |
311 | /* |
312 | * The functions below use the observation that each wakeup event starts a | |
313 | * period in which the system should not be suspended. The moment this period | |
314 | * will end depends on how the wakeup event is going to be processed after being | |
315 | * detected and all of the possible cases can be divided into two distinct | |
316 | * groups. | |
317 | * | |
318 | * First, a wakeup event may be detected by the same functional unit that will | |
319 | * carry out the entire processing of it and possibly will pass it to user space | |
320 | * for further processing. In that case the functional unit that has detected | |
321 | * the event may later "close" the "no suspend" period associated with it | |
322 | * directly as soon as it has been dealt with. The pair of pm_stay_awake() and | |
323 | * pm_relax(), balanced with each other, is supposed to be used in such | |
324 | * situations. | |
325 | * | |
326 | * Second, a wakeup event may be detected by one functional unit and processed | |
327 | * by another one. In that case the unit that has detected it cannot really | |
328 | * "close" the "no suspend" period associated with it, unless it knows in | |
329 | * advance what's going to happen to the event during processing. This | |
330 | * knowledge, however, may not be available to it, so it can simply specify time | |
331 | * to wait before the system can be suspended and pass it as the second | |
332 | * argument of pm_wakeup_event(). | |
074037ec RW |
333 | * |
334 | * It is valid to call pm_relax() after pm_wakeup_event(), in which case the | |
335 | * "no suspend" period will be ended either by the pm_relax(), or by the timer | |
336 | * function executed when the timer expires, whichever comes first. | |
c125e96f RW |
337 | */ |
338 | ||
074037ec RW |
339 | /** |
340 | * wakup_source_activate - Mark given wakeup source as active. | |
341 | * @ws: Wakeup source to handle. | |
342 | * | |
343 | * Update the @ws' statistics and, if @ws has just been activated, notify the PM | |
344 | * core of the event by incrementing the counter of of wakeup events being | |
345 | * processed. | |
346 | */ | |
347 | static void wakeup_source_activate(struct wakeup_source *ws) | |
348 | { | |
349 | ws->active = true; | |
350 | ws->active_count++; | |
351 | ws->timer_expires = jiffies; | |
352 | ws->last_time = ktime_get(); | |
353 | ||
023d3779 RW |
354 | /* Increment the counter of events in progress. */ |
355 | atomic_inc(&combined_event_count); | |
074037ec RW |
356 | } |
357 | ||
358 | /** | |
359 | * __pm_stay_awake - Notify the PM core of a wakeup event. | |
360 | * @ws: Wakeup source object associated with the source of the event. | |
361 | * | |
362 | * It is safe to call this function from interrupt context. | |
363 | */ | |
364 | void __pm_stay_awake(struct wakeup_source *ws) | |
365 | { | |
366 | unsigned long flags; | |
367 | ||
368 | if (!ws) | |
369 | return; | |
370 | ||
371 | spin_lock_irqsave(&ws->lock, flags); | |
372 | ws->event_count++; | |
373 | if (!ws->active) | |
374 | wakeup_source_activate(ws); | |
375 | spin_unlock_irqrestore(&ws->lock, flags); | |
376 | } | |
377 | EXPORT_SYMBOL_GPL(__pm_stay_awake); | |
378 | ||
c125e96f RW |
379 | /** |
380 | * pm_stay_awake - Notify the PM core that a wakeup event is being processed. | |
381 | * @dev: Device the wakeup event is related to. | |
382 | * | |
074037ec RW |
383 | * Notify the PM core of a wakeup event (signaled by @dev) by calling |
384 | * __pm_stay_awake for the @dev's wakeup source object. | |
c125e96f RW |
385 | * |
386 | * Call this function after detecting of a wakeup event if pm_relax() is going | |
387 | * to be called directly after processing the event (and possibly passing it to | |
388 | * user space for further processing). | |
c125e96f RW |
389 | */ |
390 | void pm_stay_awake(struct device *dev) | |
391 | { | |
392 | unsigned long flags; | |
393 | ||
074037ec RW |
394 | if (!dev) |
395 | return; | |
c125e96f | 396 | |
074037ec RW |
397 | spin_lock_irqsave(&dev->power.lock, flags); |
398 | __pm_stay_awake(dev->power.wakeup); | |
399 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 400 | } |
074037ec | 401 | EXPORT_SYMBOL_GPL(pm_stay_awake); |
c125e96f RW |
402 | |
403 | /** | |
074037ec RW |
404 | * wakup_source_deactivate - Mark given wakeup source as inactive. |
405 | * @ws: Wakeup source to handle. | |
c125e96f | 406 | * |
074037ec RW |
407 | * Update the @ws' statistics and notify the PM core that the wakeup source has |
408 | * become inactive by decrementing the counter of wakeup events being processed | |
409 | * and incrementing the counter of registered wakeup events. | |
410 | */ | |
411 | static void wakeup_source_deactivate(struct wakeup_source *ws) | |
412 | { | |
413 | ktime_t duration; | |
414 | ktime_t now; | |
415 | ||
416 | ws->relax_count++; | |
417 | /* | |
418 | * __pm_relax() may be called directly or from a timer function. | |
419 | * If it is called directly right after the timer function has been | |
420 | * started, but before the timer function calls __pm_relax(), it is | |
421 | * possible that __pm_stay_awake() will be called in the meantime and | |
422 | * will set ws->active. Then, ws->active may be cleared immediately | |
423 | * by the __pm_relax() called from the timer function, but in such a | |
424 | * case ws->relax_count will be different from ws->active_count. | |
425 | */ | |
426 | if (ws->relax_count != ws->active_count) { | |
427 | ws->relax_count--; | |
428 | return; | |
429 | } | |
430 | ||
431 | ws->active = false; | |
432 | ||
433 | now = ktime_get(); | |
434 | duration = ktime_sub(now, ws->last_time); | |
435 | ws->total_time = ktime_add(ws->total_time, duration); | |
436 | if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) | |
437 | ws->max_time = duration; | |
438 | ||
439 | del_timer(&ws->timer); | |
440 | ||
441 | /* | |
023d3779 RW |
442 | * Increment the counter of registered wakeup events and decrement the |
443 | * couter of wakeup events in progress simultaneously. | |
074037ec | 444 | */ |
023d3779 | 445 | atomic_add(MAX_IN_PROGRESS, &combined_event_count); |
074037ec RW |
446 | } |
447 | ||
448 | /** | |
449 | * __pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
450 | * @ws: Wakeup source object associated with the source of the event. | |
c125e96f RW |
451 | * |
452 | * Call this function for wakeup events whose processing started with calling | |
074037ec | 453 | * __pm_stay_awake(). |
c125e96f RW |
454 | * |
455 | * It is safe to call it from interrupt context. | |
456 | */ | |
074037ec | 457 | void __pm_relax(struct wakeup_source *ws) |
c125e96f RW |
458 | { |
459 | unsigned long flags; | |
460 | ||
074037ec RW |
461 | if (!ws) |
462 | return; | |
463 | ||
464 | spin_lock_irqsave(&ws->lock, flags); | |
465 | if (ws->active) | |
466 | wakeup_source_deactivate(ws); | |
467 | spin_unlock_irqrestore(&ws->lock, flags); | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(__pm_relax); | |
470 | ||
471 | /** | |
472 | * pm_relax - Notify the PM core that processing of a wakeup event has ended. | |
473 | * @dev: Device that signaled the event. | |
474 | * | |
475 | * Execute __pm_relax() for the @dev's wakeup source object. | |
476 | */ | |
477 | void pm_relax(struct device *dev) | |
478 | { | |
479 | unsigned long flags; | |
480 | ||
481 | if (!dev) | |
482 | return; | |
483 | ||
484 | spin_lock_irqsave(&dev->power.lock, flags); | |
485 | __pm_relax(dev->power.wakeup); | |
486 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
c125e96f | 487 | } |
074037ec | 488 | EXPORT_SYMBOL_GPL(pm_relax); |
c125e96f RW |
489 | |
490 | /** | |
4eb241e5 | 491 | * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. |
074037ec | 492 | * @data: Address of the wakeup source object associated with the event source. |
c125e96f | 493 | * |
074037ec | 494 | * Call __pm_relax() for the wakeup source whose address is stored in @data. |
c125e96f | 495 | */ |
4eb241e5 | 496 | static void pm_wakeup_timer_fn(unsigned long data) |
074037ec RW |
497 | { |
498 | __pm_relax((struct wakeup_source *)data); | |
499 | } | |
500 | ||
501 | /** | |
502 | * __pm_wakeup_event - Notify the PM core of a wakeup event. | |
503 | * @ws: Wakeup source object associated with the event source. | |
504 | * @msec: Anticipated event processing time (in milliseconds). | |
505 | * | |
506 | * Notify the PM core of a wakeup event whose source is @ws that will take | |
507 | * approximately @msec milliseconds to be processed by the kernel. If @ws is | |
508 | * not active, activate it. If @msec is nonzero, set up the @ws' timer to | |
509 | * execute pm_wakeup_timer_fn() in future. | |
510 | * | |
511 | * It is safe to call this function from interrupt context. | |
512 | */ | |
513 | void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) | |
c125e96f | 514 | { |
4eb241e5 | 515 | unsigned long flags; |
074037ec | 516 | unsigned long expires; |
c125e96f | 517 | |
074037ec RW |
518 | if (!ws) |
519 | return; | |
520 | ||
521 | spin_lock_irqsave(&ws->lock, flags); | |
522 | ||
523 | ws->event_count++; | |
524 | if (!ws->active) | |
525 | wakeup_source_activate(ws); | |
526 | ||
527 | if (!msec) { | |
528 | wakeup_source_deactivate(ws); | |
529 | goto unlock; | |
4eb241e5 | 530 | } |
074037ec RW |
531 | |
532 | expires = jiffies + msecs_to_jiffies(msec); | |
533 | if (!expires) | |
534 | expires = 1; | |
535 | ||
536 | if (time_after(expires, ws->timer_expires)) { | |
537 | mod_timer(&ws->timer, expires); | |
538 | ws->timer_expires = expires; | |
539 | } | |
540 | ||
541 | unlock: | |
542 | spin_unlock_irqrestore(&ws->lock, flags); | |
c125e96f | 543 | } |
074037ec RW |
544 | EXPORT_SYMBOL_GPL(__pm_wakeup_event); |
545 | ||
c125e96f RW |
546 | |
547 | /** | |
548 | * pm_wakeup_event - Notify the PM core of a wakeup event. | |
549 | * @dev: Device the wakeup event is related to. | |
550 | * @msec: Anticipated event processing time (in milliseconds). | |
551 | * | |
074037ec | 552 | * Call __pm_wakeup_event() for the @dev's wakeup source object. |
c125e96f RW |
553 | */ |
554 | void pm_wakeup_event(struct device *dev, unsigned int msec) | |
555 | { | |
556 | unsigned long flags; | |
c125e96f | 557 | |
074037ec RW |
558 | if (!dev) |
559 | return; | |
c125e96f | 560 | |
074037ec RW |
561 | spin_lock_irqsave(&dev->power.lock, flags); |
562 | __pm_wakeup_event(dev->power.wakeup, msec); | |
563 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
564 | } | |
565 | EXPORT_SYMBOL_GPL(pm_wakeup_event); | |
4eb241e5 | 566 | |
074037ec RW |
567 | /** |
568 | * pm_wakeup_update_hit_counts - Update hit counts of all active wakeup sources. | |
569 | */ | |
570 | static void pm_wakeup_update_hit_counts(void) | |
571 | { | |
572 | unsigned long flags; | |
573 | struct wakeup_source *ws; | |
4eb241e5 | 574 | |
074037ec RW |
575 | rcu_read_lock(); |
576 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) { | |
577 | spin_lock_irqsave(&ws->lock, flags); | |
578 | if (ws->active) | |
579 | ws->hit_count++; | |
580 | spin_unlock_irqrestore(&ws->lock, flags); | |
c125e96f | 581 | } |
074037ec | 582 | rcu_read_unlock(); |
c125e96f RW |
583 | } |
584 | ||
585 | /** | |
a2867e08 | 586 | * pm_wakeup_pending - Check if power transition in progress should be aborted. |
c125e96f RW |
587 | * |
588 | * Compare the current number of registered wakeup events with its preserved | |
a2867e08 RW |
589 | * value from the past and return true if new wakeup events have been registered |
590 | * since the old value was stored. Also return true if the current number of | |
591 | * wakeup events being processed is different from zero. | |
c125e96f | 592 | */ |
a2867e08 | 593 | bool pm_wakeup_pending(void) |
c125e96f RW |
594 | { |
595 | unsigned long flags; | |
a2867e08 | 596 | bool ret = false; |
c125e96f RW |
597 | |
598 | spin_lock_irqsave(&events_lock, flags); | |
599 | if (events_check_enabled) { | |
023d3779 RW |
600 | unsigned int cnt, inpr; |
601 | ||
602 | split_counters(&cnt, &inpr); | |
603 | ret = (cnt != saved_count || inpr > 0); | |
a2867e08 | 604 | events_check_enabled = !ret; |
c125e96f RW |
605 | } |
606 | spin_unlock_irqrestore(&events_lock, flags); | |
a2867e08 | 607 | if (ret) |
074037ec | 608 | pm_wakeup_update_hit_counts(); |
c125e96f RW |
609 | return ret; |
610 | } | |
611 | ||
612 | /** | |
613 | * pm_get_wakeup_count - Read the number of registered wakeup events. | |
614 | * @count: Address to store the value at. | |
615 | * | |
616 | * Store the number of registered wakeup events at the address in @count. Block | |
617 | * if the current number of wakeup events being processed is nonzero. | |
618 | * | |
790c7885 | 619 | * Return 'false' if the wait for the number of wakeup events being processed to |
c125e96f | 620 | * drop down to zero has been interrupted by a signal (and the current number |
790c7885 | 621 | * of wakeup events being processed is still nonzero). Otherwise return 'true'. |
c125e96f | 622 | */ |
074037ec | 623 | bool pm_get_wakeup_count(unsigned int *count) |
c125e96f | 624 | { |
023d3779 | 625 | unsigned int cnt, inpr; |
c125e96f | 626 | |
023d3779 RW |
627 | for (;;) { |
628 | split_counters(&cnt, &inpr); | |
629 | if (inpr == 0 || signal_pending(current)) | |
630 | break; | |
074037ec RW |
631 | pm_wakeup_update_hit_counts(); |
632 | schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT)); | |
c125e96f | 633 | } |
074037ec | 634 | |
023d3779 RW |
635 | split_counters(&cnt, &inpr); |
636 | *count = cnt; | |
637 | return !inpr; | |
c125e96f RW |
638 | } |
639 | ||
640 | /** | |
641 | * pm_save_wakeup_count - Save the current number of registered wakeup events. | |
642 | * @count: Value to compare with the current number of registered wakeup events. | |
643 | * | |
644 | * If @count is equal to the current number of registered wakeup events and the | |
645 | * current number of wakeup events being processed is zero, store @count as the | |
378eef99 RW |
646 | * old number of registered wakeup events for pm_check_wakeup_events(), enable |
647 | * wakeup events detection and return 'true'. Otherwise disable wakeup events | |
648 | * detection and return 'false'. | |
c125e96f | 649 | */ |
074037ec | 650 | bool pm_save_wakeup_count(unsigned int count) |
c125e96f | 651 | { |
023d3779 | 652 | unsigned int cnt, inpr; |
c125e96f | 653 | |
378eef99 | 654 | events_check_enabled = false; |
c125e96f | 655 | spin_lock_irq(&events_lock); |
023d3779 RW |
656 | split_counters(&cnt, &inpr); |
657 | if (cnt == count && inpr == 0) { | |
074037ec | 658 | saved_count = count; |
c125e96f | 659 | events_check_enabled = true; |
c125e96f RW |
660 | } |
661 | spin_unlock_irq(&events_lock); | |
378eef99 | 662 | if (!events_check_enabled) |
074037ec | 663 | pm_wakeup_update_hit_counts(); |
378eef99 | 664 | return events_check_enabled; |
c125e96f | 665 | } |
9c034392 RW |
666 | |
667 | static struct dentry *wakeup_sources_stats_dentry; | |
668 | ||
669 | /** | |
670 | * print_wakeup_source_stats - Print wakeup source statistics information. | |
671 | * @m: seq_file to print the statistics into. | |
672 | * @ws: Wakeup source object to print the statistics for. | |
673 | */ | |
674 | static int print_wakeup_source_stats(struct seq_file *m, | |
675 | struct wakeup_source *ws) | |
676 | { | |
677 | unsigned long flags; | |
678 | ktime_t total_time; | |
679 | ktime_t max_time; | |
680 | unsigned long active_count; | |
681 | ktime_t active_time; | |
682 | int ret; | |
683 | ||
684 | spin_lock_irqsave(&ws->lock, flags); | |
685 | ||
686 | total_time = ws->total_time; | |
687 | max_time = ws->max_time; | |
688 | active_count = ws->active_count; | |
689 | if (ws->active) { | |
690 | active_time = ktime_sub(ktime_get(), ws->last_time); | |
691 | total_time = ktime_add(total_time, active_time); | |
692 | if (active_time.tv64 > max_time.tv64) | |
693 | max_time = active_time; | |
694 | } else { | |
695 | active_time = ktime_set(0, 0); | |
696 | } | |
697 | ||
698 | ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t" | |
699 | "%lld\t\t%lld\t\t%lld\t\t%lld\n", | |
700 | ws->name, active_count, ws->event_count, ws->hit_count, | |
701 | ktime_to_ms(active_time), ktime_to_ms(total_time), | |
702 | ktime_to_ms(max_time), ktime_to_ms(ws->last_time)); | |
703 | ||
704 | spin_unlock_irqrestore(&ws->lock, flags); | |
705 | ||
706 | return ret; | |
707 | } | |
708 | ||
709 | /** | |
710 | * wakeup_sources_stats_show - Print wakeup sources statistics information. | |
711 | * @m: seq_file to print the statistics into. | |
712 | */ | |
713 | static int wakeup_sources_stats_show(struct seq_file *m, void *unused) | |
714 | { | |
715 | struct wakeup_source *ws; | |
716 | ||
717 | seq_puts(m, "name\t\tactive_count\tevent_count\thit_count\t" | |
718 | "active_since\ttotal_time\tmax_time\tlast_change\n"); | |
719 | ||
720 | rcu_read_lock(); | |
721 | list_for_each_entry_rcu(ws, &wakeup_sources, entry) | |
722 | print_wakeup_source_stats(m, ws); | |
723 | rcu_read_unlock(); | |
724 | ||
725 | return 0; | |
726 | } | |
727 | ||
728 | static int wakeup_sources_stats_open(struct inode *inode, struct file *file) | |
729 | { | |
730 | return single_open(file, wakeup_sources_stats_show, NULL); | |
731 | } | |
732 | ||
733 | static const struct file_operations wakeup_sources_stats_fops = { | |
734 | .owner = THIS_MODULE, | |
735 | .open = wakeup_sources_stats_open, | |
736 | .read = seq_read, | |
737 | .llseek = seq_lseek, | |
738 | .release = single_release, | |
739 | }; | |
740 | ||
741 | static int __init wakeup_sources_debugfs_init(void) | |
742 | { | |
743 | wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources", | |
744 | S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops); | |
745 | return 0; | |
746 | } | |
747 | ||
748 | postcore_initcall(wakeup_sources_debugfs_init); |