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