1 /*
2 * drivers/base/power/runtime.c - Helper functions for device runtime PM
3 *
4 * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5 * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu>
6 *
7 * This file is released under the GPLv2.
8 */
9
10 #include <linux/sched.h>
11 #include <linux/export.h>
12 #include <linux/pm_runtime.h>
13 #include <trace/events/rpm.h>
14 #include "power.h"
15
16 static int rpm_resume(struct device *dev, int rpmflags);
17 static int rpm_suspend(struct device *dev, int rpmflags);
18
19 /**
20 * update_pm_runtime_accounting - Update the time accounting of power states
21 * @dev: Device to update the accounting for
22 *
23 * In order to be able to have time accounting of the various power states
24 * (as used by programs such as PowerTOP to show the effectiveness of runtime
25 * PM), we need to track the time spent in each state.
26 * update_pm_runtime_accounting must be called each time before the
27 * runtime_status field is updated, to account the time in the old state
28 * correctly.
29 */
update_pm_runtime_accounting(struct device * dev)30 void update_pm_runtime_accounting(struct device *dev)
31 {
32 unsigned long now = jiffies;
33 unsigned long delta;
34
35 delta = now - dev->power.accounting_timestamp;
36
37 dev->power.accounting_timestamp = now;
38
39 if (dev->power.disable_depth > 0)
40 return;
41
42 if (dev->power.runtime_status == RPM_SUSPENDED)
43 dev->power.suspended_jiffies += delta;
44 else
45 dev->power.active_jiffies += delta;
46 }
47
__update_runtime_status(struct device * dev,enum rpm_status status)48 static void __update_runtime_status(struct device *dev, enum rpm_status status)
49 {
50 update_pm_runtime_accounting(dev);
51 dev->power.runtime_status = status;
52 }
53
54 /**
55 * pm_runtime_deactivate_timer - Deactivate given device's suspend timer.
56 * @dev: Device to handle.
57 */
pm_runtime_deactivate_timer(struct device * dev)58 static void pm_runtime_deactivate_timer(struct device *dev)
59 {
60 if (dev->power.timer_expires > 0) {
61 del_timer(&dev->power.suspend_timer);
62 dev->power.timer_expires = 0;
63 }
64 }
65
66 /**
67 * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests.
68 * @dev: Device to handle.
69 */
pm_runtime_cancel_pending(struct device * dev)70 static void pm_runtime_cancel_pending(struct device *dev)
71 {
72 pm_runtime_deactivate_timer(dev);
73 /*
74 * In case there's a request pending, make sure its work function will
75 * return without doing anything.
76 */
77 dev->power.request = RPM_REQ_NONE;
78 }
79
80 /*
81 * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time.
82 * @dev: Device to handle.
83 *
84 * Compute the autosuspend-delay expiration time based on the device's
85 * power.last_busy time. If the delay has already expired or is disabled
86 * (negative) or the power.use_autosuspend flag isn't set, return 0.
87 * Otherwise return the expiration time in jiffies (adjusted to be nonzero).
88 *
89 * This function may be called either with or without dev->power.lock held.
90 * Either way it can be racy, since power.last_busy may be updated at any time.
91 */
pm_runtime_autosuspend_expiration(struct device * dev)92 unsigned long pm_runtime_autosuspend_expiration(struct device *dev)
93 {
94 int autosuspend_delay;
95 long elapsed;
96 unsigned long last_busy;
97 unsigned long expires = 0;
98
99 if (!dev->power.use_autosuspend)
100 goto out;
101
102 autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay);
103 if (autosuspend_delay < 0)
104 goto out;
105
106 last_busy = ACCESS_ONCE(dev->power.last_busy);
107 elapsed = jiffies - last_busy;
108 if (elapsed < 0)
109 goto out; /* jiffies has wrapped around. */
110
111 /*
112 * If the autosuspend_delay is >= 1 second, align the timer by rounding
113 * up to the nearest second.
114 */
115 expires = last_busy + msecs_to_jiffies(autosuspend_delay);
116 if (autosuspend_delay >= 1000)
117 expires = round_jiffies(expires);
118 expires += !expires;
119 if (elapsed >= expires - last_busy)
120 expires = 0; /* Already expired. */
121
122 out:
123 return expires;
124 }
125 EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration);
126
127 /**
128 * rpm_check_suspend_allowed - Test whether a device may be suspended.
129 * @dev: Device to test.
130 */
rpm_check_suspend_allowed(struct device * dev)131 static int rpm_check_suspend_allowed(struct device *dev)
132 {
133 int retval = 0;
134
135 if (dev->power.runtime_error)
136 retval = -EINVAL;
137 else if (dev->power.disable_depth > 0)
138 retval = -EACCES;
139 else if (atomic_read(&dev->power.usage_count) > 0)
140 retval = -EAGAIN;
141 else if (!pm_children_suspended(dev))
142 retval = -EBUSY;
143
144 /* Pending resume requests take precedence over suspends. */
145 else if ((dev->power.deferred_resume
146 && dev->power.runtime_status == RPM_SUSPENDING)
147 || (dev->power.request_pending
148 && dev->power.request == RPM_REQ_RESUME))
149 retval = -EAGAIN;
150 else if (dev->power.runtime_status == RPM_SUSPENDED)
151 retval = 1;
152
153 return retval;
154 }
155
156 /**
157 * __rpm_callback - Run a given runtime PM callback for a given device.
158 * @cb: Runtime PM callback to run.
159 * @dev: Device to run the callback for.
160 */
__rpm_callback(int (* cb)(struct device *),struct device * dev)161 static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
162 __releases(&dev->power.lock) __acquires(&dev->power.lock)
163 {
164 int retval;
165
166 if (dev->power.irq_safe)
167 spin_unlock(&dev->power.lock);
168 else
169 spin_unlock_irq(&dev->power.lock);
170
171 retval = cb(dev);
172
173 if (dev->power.irq_safe)
174 spin_lock(&dev->power.lock);
175 else
176 spin_lock_irq(&dev->power.lock);
177
178 return retval;
179 }
180
181 /**
182 * rpm_idle - Notify device bus type if the device can be suspended.
183 * @dev: Device to notify the bus type about.
184 * @rpmflags: Flag bits.
185 *
186 * Check if the device's runtime PM status allows it to be suspended. If
187 * another idle notification has been started earlier, return immediately. If
188 * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise
189 * run the ->runtime_idle() callback directly.
190 *
191 * This function must be called under dev->power.lock with interrupts disabled.
192 */
rpm_idle(struct device * dev,int rpmflags)193 static int rpm_idle(struct device *dev, int rpmflags)
194 {
195 int (*callback)(struct device *);
196 int retval;
197
198 trace_rpm_idle(dev, rpmflags);
199 retval = rpm_check_suspend_allowed(dev);
200 if (retval < 0)
201 ; /* Conditions are wrong. */
202
203 /* Idle notifications are allowed only in the RPM_ACTIVE state. */
204 else if (dev->power.runtime_status != RPM_ACTIVE)
205 retval = -EAGAIN;
206
207 /*
208 * Any pending request other than an idle notification takes
209 * precedence over us, except that the timer may be running.
210 */
211 else if (dev->power.request_pending &&
212 dev->power.request > RPM_REQ_IDLE)
213 retval = -EAGAIN;
214
215 /* Act as though RPM_NOWAIT is always set. */
216 else if (dev->power.idle_notification)
217 retval = -EINPROGRESS;
218 if (retval)
219 goto out;
220
221 /* Pending requests need to be canceled. */
222 dev->power.request = RPM_REQ_NONE;
223
224 if (dev->power.no_callbacks) {
225 /* Assume ->runtime_idle() callback would have suspended. */
226 retval = rpm_suspend(dev, rpmflags);
227 goto out;
228 }
229
230 /* Carry out an asynchronous or a synchronous idle notification. */
231 if (rpmflags & RPM_ASYNC) {
232 dev->power.request = RPM_REQ_IDLE;
233 if (!dev->power.request_pending) {
234 dev->power.request_pending = true;
235 queue_work(pm_wq, &dev->power.work);
236 }
237 goto out;
238 }
239
240 dev->power.idle_notification = true;
241
242 if (dev->pm_domain)
243 callback = dev->pm_domain->ops.runtime_idle;
244 else if (dev->type && dev->type->pm)
245 callback = dev->type->pm->runtime_idle;
246 else if (dev->class && dev->class->pm)
247 callback = dev->class->pm->runtime_idle;
248 else if (dev->bus && dev->bus->pm)
249 callback = dev->bus->pm->runtime_idle;
250 else
251 callback = NULL;
252
253 if (!callback && dev->driver && dev->driver->pm)
254 callback = dev->driver->pm->runtime_idle;
255
256 if (callback)
257 __rpm_callback(callback, dev);
258
259 dev->power.idle_notification = false;
260 wake_up_all(&dev->power.wait_queue);
261
262 out:
263 trace_rpm_return_int(dev, _THIS_IP_, retval);
264 return retval;
265 }
266
267 /**
268 * rpm_callback - Run a given runtime PM callback for a given device.
269 * @cb: Runtime PM callback to run.
270 * @dev: Device to run the callback for.
271 */
rpm_callback(int (* cb)(struct device *),struct device * dev)272 static int rpm_callback(int (*cb)(struct device *), struct device *dev)
273 {
274 int retval;
275
276 if (!cb)
277 return -ENOSYS;
278
279 retval = __rpm_callback(cb, dev);
280
281 dev->power.runtime_error = retval;
282 return retval != -EACCES ? retval : -EIO;
283 }
284
285 struct rpm_qos_data {
286 ktime_t time_now;
287 s64 constraint_ns;
288 };
289
290 /**
291 * rpm_update_qos_constraint - Update a given PM QoS constraint data.
292 * @dev: Device whose timing data to use.
293 * @data: PM QoS constraint data to update.
294 *
295 * Use the suspend timing data of @dev to update PM QoS constraint data pointed
296 * to by @data.
297 */
rpm_update_qos_constraint(struct device * dev,void * data)298 static int rpm_update_qos_constraint(struct device *dev, void *data)
299 {
300 struct rpm_qos_data *qos = data;
301 unsigned long flags;
302 s64 delta_ns;
303 int ret = 0;
304
305 spin_lock_irqsave(&dev->power.lock, flags);
306
307 if (dev->power.max_time_suspended_ns < 0)
308 goto out;
309
310 delta_ns = dev->power.max_time_suspended_ns -
311 ktime_to_ns(ktime_sub(qos->time_now, dev->power.suspend_time));
312 if (delta_ns <= 0) {
313 ret = -EBUSY;
314 goto out;
315 }
316
317 if (qos->constraint_ns > delta_ns || qos->constraint_ns == 0)
318 qos->constraint_ns = delta_ns;
319
320 out:
321 spin_unlock_irqrestore(&dev->power.lock, flags);
322
323 return ret;
324 }
325
326 /**
327 * rpm_suspend - Carry out runtime suspend of given device.
328 * @dev: Device to suspend.
329 * @rpmflags: Flag bits.
330 *
331 * Check if the device's runtime PM status allows it to be suspended.
332 * Cancel a pending idle notification, autosuspend or suspend. If
333 * another suspend has been started earlier, either return immediately
334 * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC
335 * flags. If the RPM_ASYNC flag is set then queue a suspend request;
336 * otherwise run the ->runtime_suspend() callback directly. When
337 * ->runtime_suspend succeeded, if a deferred resume was requested while
338 * the callback was running then carry it out, otherwise send an idle
339 * notification for its parent (if the suspend succeeded and both
340 * ignore_children of parent->power and irq_safe of dev->power are not set).
341 * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO
342 * flag is set and the next autosuspend-delay expiration time is in the
343 * future, schedule another autosuspend attempt.
344 *
345 * This function must be called under dev->power.lock with interrupts disabled.
346 */
rpm_suspend(struct device * dev,int rpmflags)347 static int rpm_suspend(struct device *dev, int rpmflags)
348 __releases(&dev->power.lock) __acquires(&dev->power.lock)
349 {
350 int (*callback)(struct device *);
351 struct device *parent = NULL;
352 struct rpm_qos_data qos;
353 int retval;
354
355 trace_rpm_suspend(dev, rpmflags);
356
357 repeat:
358 retval = rpm_check_suspend_allowed(dev);
359
360 if (retval < 0)
361 ; /* Conditions are wrong. */
362
363 /* Synchronous suspends are not allowed in the RPM_RESUMING state. */
364 else if (dev->power.runtime_status == RPM_RESUMING &&
365 !(rpmflags & RPM_ASYNC))
366 retval = -EAGAIN;
367 if (retval)
368 goto out;
369
370 /* If the autosuspend_delay time hasn't expired yet, reschedule. */
371 if ((rpmflags & RPM_AUTO)
372 && dev->power.runtime_status != RPM_SUSPENDING) {
373 unsigned long expires = pm_runtime_autosuspend_expiration(dev);
374
375 if (expires != 0) {
376 /* Pending requests need to be canceled. */
377 dev->power.request = RPM_REQ_NONE;
378
379 /*
380 * Optimization: If the timer is already running and is
381 * set to expire at or before the autosuspend delay,
382 * avoid the overhead of resetting it. Just let it
383 * expire; pm_suspend_timer_fn() will take care of the
384 * rest.
385 */
386 if (!(dev->power.timer_expires && time_before_eq(
387 dev->power.timer_expires, expires))) {
388 dev->power.timer_expires = expires;
389 mod_timer(&dev->power.suspend_timer, expires);
390 }
391 dev->power.timer_autosuspends = 1;
392 goto out;
393 }
394 }
395
396 /* Other scheduled or pending requests need to be canceled. */
397 pm_runtime_cancel_pending(dev);
398
399 if (dev->power.runtime_status == RPM_SUSPENDING) {
400 DEFINE_WAIT(wait);
401
402 if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) {
403 retval = -EINPROGRESS;
404 goto out;
405 }
406
407 if (dev->power.irq_safe) {
408 spin_unlock(&dev->power.lock);
409
410 cpu_relax();
411
412 spin_lock(&dev->power.lock);
413 goto repeat;
414 }
415
416 /* Wait for the other suspend running in parallel with us. */
417 for (;;) {
418 prepare_to_wait(&dev->power.wait_queue, &wait,
419 TASK_UNINTERRUPTIBLE);
420 if (dev->power.runtime_status != RPM_SUSPENDING)
421 break;
422
423 spin_unlock_irq(&dev->power.lock);
424
425 schedule();
426
427 spin_lock_irq(&dev->power.lock);
428 }
429 finish_wait(&dev->power.wait_queue, &wait);
430 goto repeat;
431 }
432
433 if (dev->power.no_callbacks)
434 goto no_callback; /* Assume success. */
435
436 /* Carry out an asynchronous or a synchronous suspend. */
437 if (rpmflags & RPM_ASYNC) {
438 dev->power.request = (rpmflags & RPM_AUTO) ?
439 RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND;
440 if (!dev->power.request_pending) {
441 dev->power.request_pending = true;
442 queue_work(pm_wq, &dev->power.work);
443 }
444 goto out;
445 }
446
447 qos.constraint_ns = __dev_pm_qos_read_value(dev);
448 if (qos.constraint_ns < 0) {
449 /* Negative constraint means "never suspend". */
450 retval = -EPERM;
451 goto out;
452 }
453 qos.constraint_ns *= NSEC_PER_USEC;
454 qos.time_now = ktime_get();
455
456 __update_runtime_status(dev, RPM_SUSPENDING);
457
458 if (!dev->power.ignore_children) {
459 if (dev->power.irq_safe)
460 spin_unlock(&dev->power.lock);
461 else
462 spin_unlock_irq(&dev->power.lock);
463
464 retval = device_for_each_child(dev, &qos,
465 rpm_update_qos_constraint);
466
467 if (dev->power.irq_safe)
468 spin_lock(&dev->power.lock);
469 else
470 spin_lock_irq(&dev->power.lock);
471
472 if (retval)
473 goto fail;
474 }
475
476 dev->power.suspend_time = qos.time_now;
477 dev->power.max_time_suspended_ns = qos.constraint_ns ? : -1;
478
479 if (dev->pm_domain)
480 callback = dev->pm_domain->ops.runtime_suspend;
481 else if (dev->type && dev->type->pm)
482 callback = dev->type->pm->runtime_suspend;
483 else if (dev->class && dev->class->pm)
484 callback = dev->class->pm->runtime_suspend;
485 else if (dev->bus && dev->bus->pm)
486 callback = dev->bus->pm->runtime_suspend;
487 else
488 callback = NULL;
489
490 if (!callback && dev->driver && dev->driver->pm)
491 callback = dev->driver->pm->runtime_suspend;
492
493 retval = rpm_callback(callback, dev);
494 if (retval)
495 goto fail;
496
497 no_callback:
498 __update_runtime_status(dev, RPM_SUSPENDED);
499 pm_runtime_deactivate_timer(dev);
500
501 if (dev->parent) {
502 parent = dev->parent;
503 atomic_add_unless(&parent->power.child_count, -1, 0);
504 }
505 wake_up_all(&dev->power.wait_queue);
506
507 if (dev->power.deferred_resume) {
508 dev->power.deferred_resume = false;
509 rpm_resume(dev, 0);
510 retval = -EAGAIN;
511 goto out;
512 }
513
514 /* Maybe the parent is now able to suspend. */
515 if (parent && !parent->power.ignore_children && !dev->power.irq_safe) {
516 spin_unlock(&dev->power.lock);
517
518 spin_lock(&parent->power.lock);
519 rpm_idle(parent, RPM_ASYNC);
520 spin_unlock(&parent->power.lock);
521
522 spin_lock(&dev->power.lock);
523 }
524
525 out:
526 trace_rpm_return_int(dev, _THIS_IP_, retval);
527
528 return retval;
529
530 fail:
531 __update_runtime_status(dev, RPM_ACTIVE);
532 dev->power.suspend_time = ktime_set(0, 0);
533 dev->power.max_time_suspended_ns = -1;
534 dev->power.deferred_resume = false;
535 wake_up_all(&dev->power.wait_queue);
536
537 if (retval == -EAGAIN || retval == -EBUSY) {
538 dev->power.runtime_error = 0;
539
540 /*
541 * If the callback routine failed an autosuspend, and
542 * if the last_busy time has been updated so that there
543 * is a new autosuspend expiration time, automatically
544 * reschedule another autosuspend.
545 */
546 if ((rpmflags & RPM_AUTO) &&
547 pm_runtime_autosuspend_expiration(dev) != 0)
548 goto repeat;
549 } else {
550 pm_runtime_cancel_pending(dev);
551 }
552 goto out;
553 }
554
555 /**
556 * rpm_resume - Carry out runtime resume of given device.
557 * @dev: Device to resume.
558 * @rpmflags: Flag bits.
559 *
560 * Check if the device's runtime PM status allows it to be resumed. Cancel
561 * any scheduled or pending requests. If another resume has been started
562 * earlier, either return immediately or wait for it to finish, depending on the
563 * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in
564 * parallel with this function, either tell the other process to resume after
565 * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC
566 * flag is set then queue a resume request; otherwise run the
567 * ->runtime_resume() callback directly. Queue an idle notification for the
568 * device if the resume succeeded.
569 *
570 * This function must be called under dev->power.lock with interrupts disabled.
571 */
rpm_resume(struct device * dev,int rpmflags)572 static int rpm_resume(struct device *dev, int rpmflags)
573 __releases(&dev->power.lock) __acquires(&dev->power.lock)
574 {
575 int (*callback)(struct device *);
576 struct device *parent = NULL;
577 int retval = 0;
578
579 trace_rpm_resume(dev, rpmflags);
580
581 repeat:
582 if (dev->power.runtime_error)
583 retval = -EINVAL;
584 else if (dev->power.disable_depth > 0)
585 retval = -EACCES;
586 if (retval)
587 goto out;
588
589 /*
590 * Other scheduled or pending requests need to be canceled. Small
591 * optimization: If an autosuspend timer is running, leave it running
592 * rather than cancelling it now only to restart it again in the near
593 * future.
594 */
595 dev->power.request = RPM_REQ_NONE;
596 if (!dev->power.timer_autosuspends)
597 pm_runtime_deactivate_timer(dev);
598
599 if (dev->power.runtime_status == RPM_ACTIVE) {
600 retval = 1;
601 goto out;
602 }
603
604 if (dev->power.runtime_status == RPM_RESUMING
605 || dev->power.runtime_status == RPM_SUSPENDING) {
606 DEFINE_WAIT(wait);
607
608 if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) {
609 if (dev->power.runtime_status == RPM_SUSPENDING)
610 dev->power.deferred_resume = true;
611 else
612 retval = -EINPROGRESS;
613 goto out;
614 }
615
616 if (dev->power.irq_safe) {
617 spin_unlock(&dev->power.lock);
618
619 cpu_relax();
620
621 spin_lock(&dev->power.lock);
622 goto repeat;
623 }
624
625 /* Wait for the operation carried out in parallel with us. */
626 for (;;) {
627 prepare_to_wait(&dev->power.wait_queue, &wait,
628 TASK_UNINTERRUPTIBLE);
629 if (dev->power.runtime_status != RPM_RESUMING
630 && dev->power.runtime_status != RPM_SUSPENDING)
631 break;
632
633 spin_unlock_irq(&dev->power.lock);
634
635 schedule();
636
637 spin_lock_irq(&dev->power.lock);
638 }
639 finish_wait(&dev->power.wait_queue, &wait);
640 goto repeat;
641 }
642
643 /*
644 * See if we can skip waking up the parent. This is safe only if
645 * power.no_callbacks is set, because otherwise we don't know whether
646 * the resume will actually succeed.
647 */
648 if (dev->power.no_callbacks && !parent && dev->parent) {
649 spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING);
650 if (dev->parent->power.disable_depth > 0
651 || dev->parent->power.ignore_children
652 || dev->parent->power.runtime_status == RPM_ACTIVE) {
653 atomic_inc(&dev->parent->power.child_count);
654 spin_unlock(&dev->parent->power.lock);
655 retval = 1;
656 goto no_callback; /* Assume success. */
657 }
658 spin_unlock(&dev->parent->power.lock);
659 }
660
661 /* Carry out an asynchronous or a synchronous resume. */
662 if (rpmflags & RPM_ASYNC) {
663 dev->power.request = RPM_REQ_RESUME;
664 if (!dev->power.request_pending) {
665 dev->power.request_pending = true;
666 queue_work(pm_wq, &dev->power.work);
667 }
668 retval = 0;
669 goto out;
670 }
671
672 if (!parent && dev->parent) {
673 /*
674 * Increment the parent's usage counter and resume it if
675 * necessary. Not needed if dev is irq-safe; then the
676 * parent is permanently resumed.
677 */
678 parent = dev->parent;
679 if (dev->power.irq_safe)
680 goto skip_parent;
681 spin_unlock(&dev->power.lock);
682
683 pm_runtime_get_noresume(parent);
684
685 spin_lock(&parent->power.lock);
686 /*
687 * We can resume if the parent's runtime PM is disabled or it
688 * is set to ignore children.
689 */
690 if (!parent->power.disable_depth
691 && !parent->power.ignore_children) {
692 rpm_resume(parent, 0);
693 if (parent->power.runtime_status != RPM_ACTIVE)
694 retval = -EBUSY;
695 }
696 spin_unlock(&parent->power.lock);
697
698 spin_lock(&dev->power.lock);
699 if (retval)
700 goto out;
701 goto repeat;
702 }
703 skip_parent:
704
705 if (dev->power.no_callbacks)
706 goto no_callback; /* Assume success. */
707
708 dev->power.suspend_time = ktime_set(0, 0);
709 dev->power.max_time_suspended_ns = -1;
710
711 __update_runtime_status(dev, RPM_RESUMING);
712
713 if (dev->pm_domain)
714 callback = dev->pm_domain->ops.runtime_resume;
715 else if (dev->type && dev->type->pm)
716 callback = dev->type->pm->runtime_resume;
717 else if (dev->class && dev->class->pm)
718 callback = dev->class->pm->runtime_resume;
719 else if (dev->bus && dev->bus->pm)
720 callback = dev->bus->pm->runtime_resume;
721 else
722 callback = NULL;
723
724 if (!callback && dev->driver && dev->driver->pm)
725 callback = dev->driver->pm->runtime_resume;
726
727 retval = rpm_callback(callback, dev);
728 if (retval) {
729 __update_runtime_status(dev, RPM_SUSPENDED);
730 pm_runtime_cancel_pending(dev);
731 } else {
732 no_callback:
733 __update_runtime_status(dev, RPM_ACTIVE);
734 if (parent)
735 atomic_inc(&parent->power.child_count);
736 }
737 wake_up_all(&dev->power.wait_queue);
738
739 if (retval >= 0)
740 rpm_idle(dev, RPM_ASYNC);
741
742 out:
743 if (parent && !dev->power.irq_safe) {
744 spin_unlock_irq(&dev->power.lock);
745
746 pm_runtime_put(parent);
747
748 spin_lock_irq(&dev->power.lock);
749 }
750
751 trace_rpm_return_int(dev, _THIS_IP_, retval);
752
753 return retval;
754 }
755
756 /**
757 * pm_runtime_work - Universal runtime PM work function.
758 * @work: Work structure used for scheduling the execution of this function.
759 *
760 * Use @work to get the device object the work is to be done for, determine what
761 * is to be done and execute the appropriate runtime PM function.
762 */
pm_runtime_work(struct work_struct * work)763 static void pm_runtime_work(struct work_struct *work)
764 {
765 struct device *dev = container_of(work, struct device, power.work);
766 enum rpm_request req;
767
768 spin_lock_irq(&dev->power.lock);
769
770 if (!dev->power.request_pending)
771 goto out;
772
773 req = dev->power.request;
774 dev->power.request = RPM_REQ_NONE;
775 dev->power.request_pending = false;
776
777 switch (req) {
778 case RPM_REQ_NONE:
779 break;
780 case RPM_REQ_IDLE:
781 rpm_idle(dev, RPM_NOWAIT);
782 break;
783 case RPM_REQ_SUSPEND:
784 rpm_suspend(dev, RPM_NOWAIT);
785 break;
786 case RPM_REQ_AUTOSUSPEND:
787 rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO);
788 break;
789 case RPM_REQ_RESUME:
790 rpm_resume(dev, RPM_NOWAIT);
791 break;
792 }
793
794 out:
795 spin_unlock_irq(&dev->power.lock);
796 }
797
798 /**
799 * pm_suspend_timer_fn - Timer function for pm_schedule_suspend().
800 * @data: Device pointer passed by pm_schedule_suspend().
801 *
802 * Check if the time is right and queue a suspend request.
803 */
pm_suspend_timer_fn(unsigned long data)804 static void pm_suspend_timer_fn(unsigned long data)
805 {
806 struct device *dev = (struct device *)data;
807 unsigned long flags;
808 unsigned long expires;
809
810 spin_lock_irqsave(&dev->power.lock, flags);
811
812 expires = dev->power.timer_expires;
813 /* If 'expire' is after 'jiffies' we've been called too early. */
814 if (expires > 0 && !time_after(expires, jiffies)) {
815 dev->power.timer_expires = 0;
816 rpm_suspend(dev, dev->power.timer_autosuspends ?
817 (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC);
818 }
819
820 spin_unlock_irqrestore(&dev->power.lock, flags);
821 }
822
823 /**
824 * pm_schedule_suspend - Set up a timer to submit a suspend request in future.
825 * @dev: Device to suspend.
826 * @delay: Time to wait before submitting a suspend request, in milliseconds.
827 */
pm_schedule_suspend(struct device * dev,unsigned int delay)828 int pm_schedule_suspend(struct device *dev, unsigned int delay)
829 {
830 unsigned long flags;
831 int retval;
832
833 spin_lock_irqsave(&dev->power.lock, flags);
834
835 if (!delay) {
836 retval = rpm_suspend(dev, RPM_ASYNC);
837 goto out;
838 }
839
840 retval = rpm_check_suspend_allowed(dev);
841 if (retval)
842 goto out;
843
844 /* Other scheduled or pending requests need to be canceled. */
845 pm_runtime_cancel_pending(dev);
846
847 dev->power.timer_expires = jiffies + msecs_to_jiffies(delay);
848 dev->power.timer_expires += !dev->power.timer_expires;
849 dev->power.timer_autosuspends = 0;
850 mod_timer(&dev->power.suspend_timer, dev->power.timer_expires);
851
852 out:
853 spin_unlock_irqrestore(&dev->power.lock, flags);
854
855 return retval;
856 }
857 EXPORT_SYMBOL_GPL(pm_schedule_suspend);
858
859 /**
860 * __pm_runtime_idle - Entry point for runtime idle operations.
861 * @dev: Device to send idle notification for.
862 * @rpmflags: Flag bits.
863 *
864 * If the RPM_GET_PUT flag is set, decrement the device's usage count and
865 * return immediately if it is larger than zero. Then carry out an idle
866 * notification, either synchronous or asynchronous.
867 *
868 * This routine may be called in atomic context if the RPM_ASYNC flag is set,
869 * or if pm_runtime_irq_safe() has been called.
870 */
__pm_runtime_idle(struct device * dev,int rpmflags)871 int __pm_runtime_idle(struct device *dev, int rpmflags)
872 {
873 unsigned long flags;
874 int retval;
875
876 might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
877
878 if (rpmflags & RPM_GET_PUT) {
879 if (!atomic_dec_and_test(&dev->power.usage_count))
880 return 0;
881 }
882
883 spin_lock_irqsave(&dev->power.lock, flags);
884 retval = rpm_idle(dev, rpmflags);
885 spin_unlock_irqrestore(&dev->power.lock, flags);
886
887 return retval;
888 }
889 EXPORT_SYMBOL_GPL(__pm_runtime_idle);
890
891 /**
892 * __pm_runtime_suspend - Entry point for runtime put/suspend operations.
893 * @dev: Device to suspend.
894 * @rpmflags: Flag bits.
895 *
896 * If the RPM_GET_PUT flag is set, decrement the device's usage count and
897 * return immediately if it is larger than zero. Then carry out a suspend,
898 * either synchronous or asynchronous.
899 *
900 * This routine may be called in atomic context if the RPM_ASYNC flag is set,
901 * or if pm_runtime_irq_safe() has been called.
902 */
__pm_runtime_suspend(struct device * dev,int rpmflags)903 int __pm_runtime_suspend(struct device *dev, int rpmflags)
904 {
905 unsigned long flags;
906 int retval;
907
908 might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
909
910 if (rpmflags & RPM_GET_PUT) {
911 if (!atomic_dec_and_test(&dev->power.usage_count))
912 return 0;
913 }
914
915 spin_lock_irqsave(&dev->power.lock, flags);
916 retval = rpm_suspend(dev, rpmflags);
917 spin_unlock_irqrestore(&dev->power.lock, flags);
918
919 return retval;
920 }
921 EXPORT_SYMBOL_GPL(__pm_runtime_suspend);
922
923 /**
924 * __pm_runtime_resume - Entry point for runtime resume operations.
925 * @dev: Device to resume.
926 * @rpmflags: Flag bits.
927 *
928 * If the RPM_GET_PUT flag is set, increment the device's usage count. Then
929 * carry out a resume, either synchronous or asynchronous.
930 *
931 * This routine may be called in atomic context if the RPM_ASYNC flag is set,
932 * or if pm_runtime_irq_safe() has been called.
933 */
__pm_runtime_resume(struct device * dev,int rpmflags)934 int __pm_runtime_resume(struct device *dev, int rpmflags)
935 {
936 unsigned long flags;
937 int retval;
938
939 might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
940
941 if (rpmflags & RPM_GET_PUT)
942 atomic_inc(&dev->power.usage_count);
943
944 spin_lock_irqsave(&dev->power.lock, flags);
945 retval = rpm_resume(dev, rpmflags);
946 spin_unlock_irqrestore(&dev->power.lock, flags);
947
948 return retval;
949 }
950 EXPORT_SYMBOL_GPL(__pm_runtime_resume);
951
952 /**
953 * __pm_runtime_set_status - Set runtime PM status of a device.
954 * @dev: Device to handle.
955 * @status: New runtime PM status of the device.
956 *
957 * If runtime PM of the device is disabled or its power.runtime_error field is
958 * different from zero, the status may be changed either to RPM_ACTIVE, or to
959 * RPM_SUSPENDED, as long as that reflects the actual state of the device.
960 * However, if the device has a parent and the parent is not active, and the
961 * parent's power.ignore_children flag is unset, the device's status cannot be
962 * set to RPM_ACTIVE, so -EBUSY is returned in that case.
963 *
964 * If successful, __pm_runtime_set_status() clears the power.runtime_error field
965 * and the device parent's counter of unsuspended children is modified to
966 * reflect the new status. If the new status is RPM_SUSPENDED, an idle
967 * notification request for the parent is submitted.
968 */
__pm_runtime_set_status(struct device * dev,unsigned int status)969 int __pm_runtime_set_status(struct device *dev, unsigned int status)
970 {
971 struct device *parent = dev->parent;
972 unsigned long flags;
973 bool notify_parent = false;
974 int error = 0;
975
976 if (status != RPM_ACTIVE && status != RPM_SUSPENDED)
977 return -EINVAL;
978
979 spin_lock_irqsave(&dev->power.lock, flags);
980
981 if (!dev->power.runtime_error && !dev->power.disable_depth) {
982 error = -EAGAIN;
983 goto out;
984 }
985
986 if (dev->power.runtime_status == status)
987 goto out_set;
988
989 if (status == RPM_SUSPENDED) {
990 /* It always is possible to set the status to 'suspended'. */
991 if (parent) {
992 atomic_add_unless(&parent->power.child_count, -1, 0);
993 notify_parent = !parent->power.ignore_children;
994 }
995 goto out_set;
996 }
997
998 if (parent) {
999 spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING);
1000
1001 /*
1002 * It is invalid to put an active child under a parent that is
1003 * not active, has runtime PM enabled and the
1004 * 'power.ignore_children' flag unset.
1005 */
1006 if (!parent->power.disable_depth
1007 && !parent->power.ignore_children
1008 && parent->power.runtime_status != RPM_ACTIVE)
1009 error = -EBUSY;
1010 else if (dev->power.runtime_status == RPM_SUSPENDED)
1011 atomic_inc(&parent->power.child_count);
1012
1013 spin_unlock(&parent->power.lock);
1014
1015 if (error)
1016 goto out;
1017 }
1018
1019 out_set:
1020 __update_runtime_status(dev, status);
1021 dev->power.runtime_error = 0;
1022 out:
1023 spin_unlock_irqrestore(&dev->power.lock, flags);
1024
1025 if (notify_parent)
1026 pm_request_idle(parent);
1027
1028 return error;
1029 }
1030 EXPORT_SYMBOL_GPL(__pm_runtime_set_status);
1031
1032 /**
1033 * __pm_runtime_barrier - Cancel pending requests and wait for completions.
1034 * @dev: Device to handle.
1035 *
1036 * Flush all pending requests for the device from pm_wq and wait for all
1037 * runtime PM operations involving the device in progress to complete.
1038 *
1039 * Should be called under dev->power.lock with interrupts disabled.
1040 */
__pm_runtime_barrier(struct device * dev)1041 static void __pm_runtime_barrier(struct device *dev)
1042 {
1043 pm_runtime_deactivate_timer(dev);
1044
1045 if (dev->power.request_pending) {
1046 dev->power.request = RPM_REQ_NONE;
1047 spin_unlock_irq(&dev->power.lock);
1048
1049 cancel_work_sync(&dev->power.work);
1050
1051 spin_lock_irq(&dev->power.lock);
1052 dev->power.request_pending = false;
1053 }
1054
1055 if (dev->power.runtime_status == RPM_SUSPENDING
1056 || dev->power.runtime_status == RPM_RESUMING
1057 || dev->power.idle_notification) {
1058 DEFINE_WAIT(wait);
1059
1060 /* Suspend, wake-up or idle notification in progress. */
1061 for (;;) {
1062 prepare_to_wait(&dev->power.wait_queue, &wait,
1063 TASK_UNINTERRUPTIBLE);
1064 if (dev->power.runtime_status != RPM_SUSPENDING
1065 && dev->power.runtime_status != RPM_RESUMING
1066 && !dev->power.idle_notification)
1067 break;
1068 spin_unlock_irq(&dev->power.lock);
1069
1070 schedule();
1071
1072 spin_lock_irq(&dev->power.lock);
1073 }
1074 finish_wait(&dev->power.wait_queue, &wait);
1075 }
1076 }
1077
1078 /**
1079 * pm_runtime_barrier - Flush pending requests and wait for completions.
1080 * @dev: Device to handle.
1081 *
1082 * Prevent the device from being suspended by incrementing its usage counter and
1083 * if there's a pending resume request for the device, wake the device up.
1084 * Next, make sure that all pending requests for the device have been flushed
1085 * from pm_wq and wait for all runtime PM operations involving the device in
1086 * progress to complete.
1087 *
1088 * Return value:
1089 * 1, if there was a resume request pending and the device had to be woken up,
1090 * 0, otherwise
1091 */
pm_runtime_barrier(struct device * dev)1092 int pm_runtime_barrier(struct device *dev)
1093 {
1094 int retval = 0;
1095
1096 pm_runtime_get_noresume(dev);
1097 spin_lock_irq(&dev->power.lock);
1098
1099 if (dev->power.request_pending
1100 && dev->power.request == RPM_REQ_RESUME) {
1101 rpm_resume(dev, 0);
1102 retval = 1;
1103 }
1104
1105 __pm_runtime_barrier(dev);
1106
1107 spin_unlock_irq(&dev->power.lock);
1108 pm_runtime_put_noidle(dev);
1109
1110 return retval;
1111 }
1112 EXPORT_SYMBOL_GPL(pm_runtime_barrier);
1113
1114 /**
1115 * __pm_runtime_disable - Disable runtime PM of a device.
1116 * @dev: Device to handle.
1117 * @check_resume: If set, check if there's a resume request for the device.
1118 *
1119 * Increment power.disable_depth for the device and if was zero previously,
1120 * cancel all pending runtime PM requests for the device and wait for all
1121 * operations in progress to complete. The device can be either active or
1122 * suspended after its runtime PM has been disabled.
1123 *
1124 * If @check_resume is set and there's a resume request pending when
1125 * __pm_runtime_disable() is called and power.disable_depth is zero, the
1126 * function will wake up the device before disabling its runtime PM.
1127 */
__pm_runtime_disable(struct device * dev,bool check_resume)1128 void __pm_runtime_disable(struct device *dev, bool check_resume)
1129 {
1130 spin_lock_irq(&dev->power.lock);
1131
1132 if (dev->power.disable_depth > 0) {
1133 dev->power.disable_depth++;
1134 goto out;
1135 }
1136
1137 /*
1138 * Wake up the device if there's a resume request pending, because that
1139 * means there probably is some I/O to process and disabling runtime PM
1140 * shouldn't prevent the device from processing the I/O.
1141 */
1142 if (check_resume && dev->power.request_pending
1143 && dev->power.request == RPM_REQ_RESUME) {
1144 /*
1145 * Prevent suspends and idle notifications from being carried
1146 * out after we have woken up the device.
1147 */
1148 pm_runtime_get_noresume(dev);
1149
1150 rpm_resume(dev, 0);
1151
1152 pm_runtime_put_noidle(dev);
1153 }
1154
1155 if (!dev->power.disable_depth++)
1156 __pm_runtime_barrier(dev);
1157
1158 out:
1159 spin_unlock_irq(&dev->power.lock);
1160 }
1161 EXPORT_SYMBOL_GPL(__pm_runtime_disable);
1162
1163 /**
1164 * pm_runtime_enable - Enable runtime PM of a device.
1165 * @dev: Device to handle.
1166 */
pm_runtime_enable(struct device * dev)1167 void pm_runtime_enable(struct device *dev)
1168 {
1169 unsigned long flags;
1170
1171 spin_lock_irqsave(&dev->power.lock, flags);
1172
1173 if (dev->power.disable_depth > 0)
1174 dev->power.disable_depth--;
1175 else
1176 dev_warn(dev, "Unbalanced %s!\n", __func__);
1177
1178 spin_unlock_irqrestore(&dev->power.lock, flags);
1179 }
1180 EXPORT_SYMBOL_GPL(pm_runtime_enable);
1181
1182 /**
1183 * pm_runtime_forbid - Block runtime PM of a device.
1184 * @dev: Device to handle.
1185 *
1186 * Increase the device's usage count and clear its power.runtime_auto flag,
1187 * so that it cannot be suspended at run time until pm_runtime_allow() is called
1188 * for it.
1189 */
pm_runtime_forbid(struct device * dev)1190 void pm_runtime_forbid(struct device *dev)
1191 {
1192 spin_lock_irq(&dev->power.lock);
1193 if (!dev->power.runtime_auto)
1194 goto out;
1195
1196 dev->power.runtime_auto = false;
1197 atomic_inc(&dev->power.usage_count);
1198 rpm_resume(dev, 0);
1199
1200 out:
1201 spin_unlock_irq(&dev->power.lock);
1202 }
1203 EXPORT_SYMBOL_GPL(pm_runtime_forbid);
1204
1205 /**
1206 * pm_runtime_allow - Unblock runtime PM of a device.
1207 * @dev: Device to handle.
1208 *
1209 * Decrease the device's usage count and set its power.runtime_auto flag.
1210 */
pm_runtime_allow(struct device * dev)1211 void pm_runtime_allow(struct device *dev)
1212 {
1213 spin_lock_irq(&dev->power.lock);
1214 if (dev->power.runtime_auto)
1215 goto out;
1216
1217 dev->power.runtime_auto = true;
1218 if (atomic_dec_and_test(&dev->power.usage_count))
1219 rpm_idle(dev, RPM_AUTO);
1220
1221 out:
1222 spin_unlock_irq(&dev->power.lock);
1223 }
1224 EXPORT_SYMBOL_GPL(pm_runtime_allow);
1225
1226 /**
1227 * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device.
1228 * @dev: Device to handle.
1229 *
1230 * Set the power.no_callbacks flag, which tells the PM core that this
1231 * device is power-managed through its parent and has no runtime PM
1232 * callbacks of its own. The runtime sysfs attributes will be removed.
1233 */
pm_runtime_no_callbacks(struct device * dev)1234 void pm_runtime_no_callbacks(struct device *dev)
1235 {
1236 spin_lock_irq(&dev->power.lock);
1237 dev->power.no_callbacks = 1;
1238 spin_unlock_irq(&dev->power.lock);
1239 if (device_is_registered(dev))
1240 rpm_sysfs_remove(dev);
1241 }
1242 EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks);
1243
1244 /**
1245 * pm_runtime_irq_safe - Leave interrupts disabled during callbacks.
1246 * @dev: Device to handle
1247 *
1248 * Set the power.irq_safe flag, which tells the PM core that the
1249 * ->runtime_suspend() and ->runtime_resume() callbacks for this device should
1250 * always be invoked with the spinlock held and interrupts disabled. It also
1251 * causes the parent's usage counter to be permanently incremented, preventing
1252 * the parent from runtime suspending -- otherwise an irq-safe child might have
1253 * to wait for a non-irq-safe parent.
1254 */
pm_runtime_irq_safe(struct device * dev)1255 void pm_runtime_irq_safe(struct device *dev)
1256 {
1257 if (dev->parent)
1258 pm_runtime_get_sync(dev->parent);
1259 spin_lock_irq(&dev->power.lock);
1260 dev->power.irq_safe = 1;
1261 spin_unlock_irq(&dev->power.lock);
1262 }
1263 EXPORT_SYMBOL_GPL(pm_runtime_irq_safe);
1264
1265 /**
1266 * update_autosuspend - Handle a change to a device's autosuspend settings.
1267 * @dev: Device to handle.
1268 * @old_delay: The former autosuspend_delay value.
1269 * @old_use: The former use_autosuspend value.
1270 *
1271 * Prevent runtime suspend if the new delay is negative and use_autosuspend is
1272 * set; otherwise allow it. Send an idle notification if suspends are allowed.
1273 *
1274 * This function must be called under dev->power.lock with interrupts disabled.
1275 */
update_autosuspend(struct device * dev,int old_delay,int old_use)1276 static void update_autosuspend(struct device *dev, int old_delay, int old_use)
1277 {
1278 int delay = dev->power.autosuspend_delay;
1279
1280 /* Should runtime suspend be prevented now? */
1281 if (dev->power.use_autosuspend && delay < 0) {
1282
1283 /* If it used to be allowed then prevent it. */
1284 if (!old_use || old_delay >= 0) {
1285 atomic_inc(&dev->power.usage_count);
1286 rpm_resume(dev, 0);
1287 }
1288 }
1289
1290 /* Runtime suspend should be allowed now. */
1291 else {
1292
1293 /* If it used to be prevented then allow it. */
1294 if (old_use && old_delay < 0)
1295 atomic_dec(&dev->power.usage_count);
1296
1297 /* Maybe we can autosuspend now. */
1298 rpm_idle(dev, RPM_AUTO);
1299 }
1300 }
1301
1302 /**
1303 * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value.
1304 * @dev: Device to handle.
1305 * @delay: Value of the new delay in milliseconds.
1306 *
1307 * Set the device's power.autosuspend_delay value. If it changes to negative
1308 * and the power.use_autosuspend flag is set, prevent runtime suspends. If it
1309 * changes the other way, allow runtime suspends.
1310 */
pm_runtime_set_autosuspend_delay(struct device * dev,int delay)1311 void pm_runtime_set_autosuspend_delay(struct device *dev, int delay)
1312 {
1313 int old_delay, old_use;
1314
1315 spin_lock_irq(&dev->power.lock);
1316 old_delay = dev->power.autosuspend_delay;
1317 old_use = dev->power.use_autosuspend;
1318 dev->power.autosuspend_delay = delay;
1319 update_autosuspend(dev, old_delay, old_use);
1320 spin_unlock_irq(&dev->power.lock);
1321 }
1322 EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay);
1323
1324 /**
1325 * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag.
1326 * @dev: Device to handle.
1327 * @use: New value for use_autosuspend.
1328 *
1329 * Set the device's power.use_autosuspend flag, and allow or prevent runtime
1330 * suspends as needed.
1331 */
__pm_runtime_use_autosuspend(struct device * dev,bool use)1332 void __pm_runtime_use_autosuspend(struct device *dev, bool use)
1333 {
1334 int old_delay, old_use;
1335
1336 spin_lock_irq(&dev->power.lock);
1337 old_delay = dev->power.autosuspend_delay;
1338 old_use = dev->power.use_autosuspend;
1339 dev->power.use_autosuspend = use;
1340 update_autosuspend(dev, old_delay, old_use);
1341 spin_unlock_irq(&dev->power.lock);
1342 }
1343 EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend);
1344
1345 /**
1346 * pm_runtime_init - Initialize runtime PM fields in given device object.
1347 * @dev: Device object to initialize.
1348 */
pm_runtime_init(struct device * dev)1349 void pm_runtime_init(struct device *dev)
1350 {
1351 dev->power.runtime_status = RPM_SUSPENDED;
1352 dev->power.idle_notification = false;
1353
1354 dev->power.disable_depth = 1;
1355 atomic_set(&dev->power.usage_count, 0);
1356
1357 dev->power.runtime_error = 0;
1358
1359 atomic_set(&dev->power.child_count, 0);
1360 pm_suspend_ignore_children(dev, false);
1361 dev->power.runtime_auto = true;
1362
1363 dev->power.request_pending = false;
1364 dev->power.request = RPM_REQ_NONE;
1365 dev->power.deferred_resume = false;
1366 dev->power.accounting_timestamp = jiffies;
1367 INIT_WORK(&dev->power.work, pm_runtime_work);
1368
1369 dev->power.timer_expires = 0;
1370 setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn,
1371 (unsigned long)dev);
1372
1373 dev->power.suspend_time = ktime_set(0, 0);
1374 dev->power.max_time_suspended_ns = -1;
1375
1376 init_waitqueue_head(&dev->power.wait_queue);
1377 }
1378
1379 /**
1380 * pm_runtime_remove - Prepare for removing a device from device hierarchy.
1381 * @dev: Device object being removed from device hierarchy.
1382 */
pm_runtime_remove(struct device * dev)1383 void pm_runtime_remove(struct device *dev)
1384 {
1385 __pm_runtime_disable(dev, false);
1386
1387 /* Change the status back to 'suspended' to match the initial status. */
1388 if (dev->power.runtime_status == RPM_ACTIVE)
1389 pm_runtime_set_suspended(dev);
1390 if (dev->power.irq_safe && dev->parent)
1391 pm_runtime_put_sync(dev->parent);
1392 }
1393
1394 /**
1395 * pm_runtime_update_max_time_suspended - Update device's suspend time data.
1396 * @dev: Device to handle.
1397 * @delta_ns: Value to subtract from the device's max_time_suspended_ns field.
1398 *
1399 * Update the device's power.max_time_suspended_ns field by subtracting
1400 * @delta_ns from it. The resulting value of power.max_time_suspended_ns is
1401 * never negative.
1402 */
pm_runtime_update_max_time_suspended(struct device * dev,s64 delta_ns)1403 void pm_runtime_update_max_time_suspended(struct device *dev, s64 delta_ns)
1404 {
1405 unsigned long flags;
1406
1407 spin_lock_irqsave(&dev->power.lock, flags);
1408
1409 if (delta_ns > 0 && dev->power.max_time_suspended_ns > 0) {
1410 if (dev->power.max_time_suspended_ns > delta_ns)
1411 dev->power.max_time_suspended_ns -= delta_ns;
1412 else
1413 dev->power.max_time_suspended_ns = 0;
1414 }
1415
1416 spin_unlock_irqrestore(&dev->power.lock, flags);
1417 }
1418