2 * drivers/base/power/main.c - Where the driver meets power management.
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
7 * This file is released under the GPLv2
10 * The driver model core calls device_pm_add() when a device is registered.
11 * This will initialize the embedded device_pm_info object in the device
12 * and add it to the list of power-controlled devices. sysfs entries for
13 * controlling device power management will also be added.
15 * A separate list is used for keeping track of power info, because the power
16 * domain dependencies may differ from the ancestral dependencies that the
17 * subsystem list maintains.
20 #include <linux/device.h>
21 #include <linux/kallsyms.h>
22 #include <linux/mutex.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/resume-trace.h>
26 #include <linux/interrupt.h>
27 #include <linux/sched.h>
28 #include <linux/async.h>
29 #include <linux/suspend.h>
35 * The entries in the dpm_list list are in a depth first order, simply
36 * because children are guaranteed to be discovered after parents, and
37 * are inserted at the back of the list on discovery.
39 * Since device_pm_add() may be called with a device lock held,
40 * we must never try to acquire a device lock while holding
45 LIST_HEAD(dpm_prepared_list
);
46 LIST_HEAD(dpm_suspended_list
);
47 LIST_HEAD(dpm_noirq_list
);
49 static DEFINE_MUTEX(dpm_list_mtx
);
50 static pm_message_t pm_transition
;
52 static int async_error
;
55 * device_pm_init - Initialize the PM-related part of a device object.
56 * @dev: Device object being initialized.
58 void device_pm_init(struct device
*dev
)
60 dev
->power
.in_suspend
= false;
61 init_completion(&dev
->power
.completion
);
62 complete_all(&dev
->power
.completion
);
63 dev
->power
.wakeup
= NULL
;
64 spin_lock_init(&dev
->power
.lock
);
66 INIT_LIST_HEAD(&dev
->power
.entry
);
70 * device_pm_lock - Lock the list of active devices used by the PM core.
72 void device_pm_lock(void)
74 mutex_lock(&dpm_list_mtx
);
78 * device_pm_unlock - Unlock the list of active devices used by the PM core.
80 void device_pm_unlock(void)
82 mutex_unlock(&dpm_list_mtx
);
86 * device_pm_add - Add a device to the PM core's list of active devices.
87 * @dev: Device to add to the list.
89 void device_pm_add(struct device
*dev
)
91 pr_debug("PM: Adding info for %s:%s\n",
92 dev
->bus
? dev
->bus
->name
: "No Bus", dev_name(dev
));
93 mutex_lock(&dpm_list_mtx
);
94 if (dev
->parent
&& dev
->parent
->power
.in_suspend
)
95 dev_warn(dev
, "parent %s should not be sleeping\n",
96 dev_name(dev
->parent
));
97 list_add_tail(&dev
->power
.entry
, &dpm_list
);
98 mutex_unlock(&dpm_list_mtx
);
102 * device_pm_remove - Remove a device from the PM core's list of active devices.
103 * @dev: Device to be removed from the list.
105 void device_pm_remove(struct device
*dev
)
107 pr_debug("PM: Removing info for %s:%s\n",
108 dev
->bus
? dev
->bus
->name
: "No Bus", dev_name(dev
));
109 complete_all(&dev
->power
.completion
);
110 mutex_lock(&dpm_list_mtx
);
111 list_del_init(&dev
->power
.entry
);
112 mutex_unlock(&dpm_list_mtx
);
113 device_wakeup_disable(dev
);
114 pm_runtime_remove(dev
);
118 * device_pm_move_before - Move device in the PM core's list of active devices.
119 * @deva: Device to move in dpm_list.
120 * @devb: Device @deva should come before.
122 void device_pm_move_before(struct device
*deva
, struct device
*devb
)
124 pr_debug("PM: Moving %s:%s before %s:%s\n",
125 deva
->bus
? deva
->bus
->name
: "No Bus", dev_name(deva
),
126 devb
->bus
? devb
->bus
->name
: "No Bus", dev_name(devb
));
127 /* Delete deva from dpm_list and reinsert before devb. */
128 list_move_tail(&deva
->power
.entry
, &devb
->power
.entry
);
132 * device_pm_move_after - Move device in the PM core's list of active devices.
133 * @deva: Device to move in dpm_list.
134 * @devb: Device @deva should come after.
136 void device_pm_move_after(struct device
*deva
, struct device
*devb
)
138 pr_debug("PM: Moving %s:%s after %s:%s\n",
139 deva
->bus
? deva
->bus
->name
: "No Bus", dev_name(deva
),
140 devb
->bus
? devb
->bus
->name
: "No Bus", dev_name(devb
));
141 /* Delete deva from dpm_list and reinsert after devb. */
142 list_move(&deva
->power
.entry
, &devb
->power
.entry
);
146 * device_pm_move_last - Move device to end of the PM core's list of devices.
147 * @dev: Device to move in dpm_list.
149 void device_pm_move_last(struct device
*dev
)
151 pr_debug("PM: Moving %s:%s to end of list\n",
152 dev
->bus
? dev
->bus
->name
: "No Bus", dev_name(dev
));
153 list_move_tail(&dev
->power
.entry
, &dpm_list
);
156 static ktime_t
initcall_debug_start(struct device
*dev
)
158 ktime_t calltime
= ktime_set(0, 0);
160 if (initcall_debug
) {
161 pr_info("calling %s+ @ %i\n",
162 dev_name(dev
), task_pid_nr(current
));
163 calltime
= ktime_get();
169 static void initcall_debug_report(struct device
*dev
, ktime_t calltime
,
172 ktime_t delta
, rettime
;
174 if (initcall_debug
) {
175 rettime
= ktime_get();
176 delta
= ktime_sub(rettime
, calltime
);
177 pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev
),
178 error
, (unsigned long long)ktime_to_ns(delta
) >> 10);
183 * dpm_wait - Wait for a PM operation to complete.
184 * @dev: Device to wait for.
185 * @async: If unset, wait only if the device's power.async_suspend flag is set.
187 static void dpm_wait(struct device
*dev
, bool async
)
192 if (async
|| (pm_async_enabled
&& dev
->power
.async_suspend
))
193 wait_for_completion(&dev
->power
.completion
);
196 static int dpm_wait_fn(struct device
*dev
, void *async_ptr
)
198 dpm_wait(dev
, *((bool *)async_ptr
));
202 static void dpm_wait_for_children(struct device
*dev
, bool async
)
204 device_for_each_child(dev
, &async
, dpm_wait_fn
);
208 * pm_op - Execute the PM operation appropriate for given PM event.
209 * @dev: Device to handle.
210 * @ops: PM operations to choose from.
211 * @state: PM transition of the system being carried out.
213 static int pm_op(struct device
*dev
,
214 const struct dev_pm_ops
*ops
,
220 calltime
= initcall_debug_start(dev
);
222 switch (state
.event
) {
223 #ifdef CONFIG_SUSPEND
224 case PM_EVENT_SUSPEND
:
226 error
= ops
->suspend(dev
);
227 suspend_report_result(ops
->suspend
, error
);
230 case PM_EVENT_RESUME
:
232 error
= ops
->resume(dev
);
233 suspend_report_result(ops
->resume
, error
);
236 #endif /* CONFIG_SUSPEND */
237 #ifdef CONFIG_HIBERNATE_CALLBACKS
238 case PM_EVENT_FREEZE
:
239 case PM_EVENT_QUIESCE
:
241 error
= ops
->freeze(dev
);
242 suspend_report_result(ops
->freeze
, error
);
245 case PM_EVENT_HIBERNATE
:
247 error
= ops
->poweroff(dev
);
248 suspend_report_result(ops
->poweroff
, error
);
252 case PM_EVENT_RECOVER
:
254 error
= ops
->thaw(dev
);
255 suspend_report_result(ops
->thaw
, error
);
258 case PM_EVENT_RESTORE
:
260 error
= ops
->restore(dev
);
261 suspend_report_result(ops
->restore
, error
);
264 #endif /* CONFIG_HIBERNATE_CALLBACKS */
269 initcall_debug_report(dev
, calltime
, error
);
275 * pm_noirq_op - Execute the PM operation appropriate for given PM event.
276 * @dev: Device to handle.
277 * @ops: PM operations to choose from.
278 * @state: PM transition of the system being carried out.
280 * The driver of @dev will not receive interrupts while this function is being
283 static int pm_noirq_op(struct device
*dev
,
284 const struct dev_pm_ops
*ops
,
288 ktime_t calltime
= ktime_set(0, 0), delta
, rettime
;
290 if (initcall_debug
) {
291 pr_info("calling %s+ @ %i, parent: %s\n",
292 dev_name(dev
), task_pid_nr(current
),
293 dev
->parent
? dev_name(dev
->parent
) : "none");
294 calltime
= ktime_get();
297 switch (state
.event
) {
298 #ifdef CONFIG_SUSPEND
299 case PM_EVENT_SUSPEND
:
300 if (ops
->suspend_noirq
) {
301 error
= ops
->suspend_noirq(dev
);
302 suspend_report_result(ops
->suspend_noirq
, error
);
305 case PM_EVENT_RESUME
:
306 if (ops
->resume_noirq
) {
307 error
= ops
->resume_noirq(dev
);
308 suspend_report_result(ops
->resume_noirq
, error
);
311 #endif /* CONFIG_SUSPEND */
312 #ifdef CONFIG_HIBERNATE_CALLBACKS
313 case PM_EVENT_FREEZE
:
314 case PM_EVENT_QUIESCE
:
315 if (ops
->freeze_noirq
) {
316 error
= ops
->freeze_noirq(dev
);
317 suspend_report_result(ops
->freeze_noirq
, error
);
320 case PM_EVENT_HIBERNATE
:
321 if (ops
->poweroff_noirq
) {
322 error
= ops
->poweroff_noirq(dev
);
323 suspend_report_result(ops
->poweroff_noirq
, error
);
327 case PM_EVENT_RECOVER
:
328 if (ops
->thaw_noirq
) {
329 error
= ops
->thaw_noirq(dev
);
330 suspend_report_result(ops
->thaw_noirq
, error
);
333 case PM_EVENT_RESTORE
:
334 if (ops
->restore_noirq
) {
335 error
= ops
->restore_noirq(dev
);
336 suspend_report_result(ops
->restore_noirq
, error
);
339 #endif /* CONFIG_HIBERNATE_CALLBACKS */
344 if (initcall_debug
) {
345 rettime
= ktime_get();
346 delta
= ktime_sub(rettime
, calltime
);
347 printk("initcall %s_i+ returned %d after %Ld usecs\n",
348 dev_name(dev
), error
,
349 (unsigned long long)ktime_to_ns(delta
) >> 10);
355 static char *pm_verb(int event
)
358 case PM_EVENT_SUSPEND
:
360 case PM_EVENT_RESUME
:
362 case PM_EVENT_FREEZE
:
364 case PM_EVENT_QUIESCE
:
366 case PM_EVENT_HIBERNATE
:
370 case PM_EVENT_RESTORE
:
372 case PM_EVENT_RECOVER
:
375 return "(unknown PM event)";
379 static void pm_dev_dbg(struct device
*dev
, pm_message_t state
, char *info
)
381 dev_dbg(dev
, "%s%s%s\n", info
, pm_verb(state
.event
),
382 ((state
.event
& PM_EVENT_SLEEP
) && device_may_wakeup(dev
)) ?
383 ", may wakeup" : "");
386 static void pm_dev_err(struct device
*dev
, pm_message_t state
, char *info
,
389 printk(KERN_ERR
"PM: Device %s failed to %s%s: error %d\n",
390 dev_name(dev
), pm_verb(state
.event
), info
, error
);
393 static void dpm_show_time(ktime_t starttime
, pm_message_t state
, char *info
)
399 calltime
= ktime_get();
400 usecs64
= ktime_to_ns(ktime_sub(calltime
, starttime
));
401 do_div(usecs64
, NSEC_PER_USEC
);
405 pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n",
406 info
?: "", info
? " " : "", pm_verb(state
.event
),
407 usecs
/ USEC_PER_MSEC
, usecs
% USEC_PER_MSEC
);
410 /*------------------------- Resume routines -------------------------*/
413 * device_resume_noirq - Execute an "early resume" callback for given device.
414 * @dev: Device to handle.
415 * @state: PM transition of the system being carried out.
417 * The driver of @dev will not receive interrupts while this function is being
420 static int device_resume_noirq(struct device
*dev
, pm_message_t state
)
427 if (dev
->pwr_domain
) {
428 pm_dev_dbg(dev
, state
, "EARLY power domain ");
429 error
= pm_noirq_op(dev
, &dev
->pwr_domain
->ops
, state
);
430 } else if (dev
->type
&& dev
->type
->pm
) {
431 pm_dev_dbg(dev
, state
, "EARLY type ");
432 error
= pm_noirq_op(dev
, dev
->type
->pm
, state
);
433 } else if (dev
->class && dev
->class->pm
) {
434 pm_dev_dbg(dev
, state
, "EARLY class ");
435 error
= pm_noirq_op(dev
, dev
->class->pm
, state
);
436 } else if (dev
->bus
&& dev
->bus
->pm
) {
437 pm_dev_dbg(dev
, state
, "EARLY ");
438 error
= pm_noirq_op(dev
, dev
->bus
->pm
, state
);
446 * dpm_resume_noirq - Execute "early resume" callbacks for non-sysdev devices.
447 * @state: PM transition of the system being carried out.
449 * Call the "noirq" resume handlers for all devices marked as DPM_OFF_IRQ and
450 * enable device drivers to receive interrupts.
452 void dpm_resume_noirq(pm_message_t state
)
454 ktime_t starttime
= ktime_get();
456 mutex_lock(&dpm_list_mtx
);
457 while (!list_empty(&dpm_noirq_list
)) {
458 struct device
*dev
= to_device(dpm_noirq_list
.next
);
462 list_move_tail(&dev
->power
.entry
, &dpm_suspended_list
);
463 mutex_unlock(&dpm_list_mtx
);
465 error
= device_resume_noirq(dev
, state
);
467 pm_dev_err(dev
, state
, " early", error
);
469 mutex_lock(&dpm_list_mtx
);
472 mutex_unlock(&dpm_list_mtx
);
473 dpm_show_time(starttime
, state
, "early");
474 resume_device_irqs();
476 EXPORT_SYMBOL_GPL(dpm_resume_noirq
);
479 * legacy_resume - Execute a legacy (bus or class) resume callback for device.
480 * @dev: Device to resume.
481 * @cb: Resume callback to execute.
483 static int legacy_resume(struct device
*dev
, int (*cb
)(struct device
*dev
))
488 calltime
= initcall_debug_start(dev
);
491 suspend_report_result(cb
, error
);
493 initcall_debug_report(dev
, calltime
, error
);
499 * device_resume - Execute "resume" callbacks for given device.
500 * @dev: Device to handle.
501 * @state: PM transition of the system being carried out.
502 * @async: If true, the device is being resumed asynchronously.
504 static int device_resume(struct device
*dev
, pm_message_t state
, bool async
)
511 dpm_wait(dev
->parent
, async
);
514 dev
->power
.in_suspend
= false;
516 if (dev
->pwr_domain
) {
517 pm_dev_dbg(dev
, state
, "power domain ");
518 error
= pm_op(dev
, &dev
->pwr_domain
->ops
, state
);
522 if (dev
->type
&& dev
->type
->pm
) {
523 pm_dev_dbg(dev
, state
, "type ");
524 error
= pm_op(dev
, dev
->type
->pm
, state
);
529 if (dev
->class->pm
) {
530 pm_dev_dbg(dev
, state
, "class ");
531 error
= pm_op(dev
, dev
->class->pm
, state
);
533 } else if (dev
->class->resume
) {
534 pm_dev_dbg(dev
, state
, "legacy class ");
535 error
= legacy_resume(dev
, dev
->class->resume
);
542 pm_dev_dbg(dev
, state
, "");
543 error
= pm_op(dev
, dev
->bus
->pm
, state
);
544 } else if (dev
->bus
->resume
) {
545 pm_dev_dbg(dev
, state
, "legacy ");
546 error
= legacy_resume(dev
, dev
->bus
->resume
);
552 complete_all(&dev
->power
.completion
);
558 static void async_resume(void *data
, async_cookie_t cookie
)
560 struct device
*dev
= (struct device
*)data
;
563 error
= device_resume(dev
, pm_transition
, true);
565 pm_dev_err(dev
, pm_transition
, " async", error
);
569 static bool is_async(struct device
*dev
)
571 return dev
->power
.async_suspend
&& pm_async_enabled
572 && !pm_trace_is_enabled();
576 * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
577 * @state: PM transition of the system being carried out.
579 * Execute the appropriate "resume" callback for all devices whose status
580 * indicates that they are suspended.
582 void dpm_resume(pm_message_t state
)
585 ktime_t starttime
= ktime_get();
589 mutex_lock(&dpm_list_mtx
);
590 pm_transition
= state
;
593 list_for_each_entry(dev
, &dpm_suspended_list
, power
.entry
) {
594 INIT_COMPLETION(dev
->power
.completion
);
597 async_schedule(async_resume
, dev
);
601 while (!list_empty(&dpm_suspended_list
)) {
602 dev
= to_device(dpm_suspended_list
.next
);
604 if (!is_async(dev
)) {
607 mutex_unlock(&dpm_list_mtx
);
609 error
= device_resume(dev
, state
, false);
611 pm_dev_err(dev
, state
, "", error
);
613 mutex_lock(&dpm_list_mtx
);
615 if (!list_empty(&dev
->power
.entry
))
616 list_move_tail(&dev
->power
.entry
, &dpm_prepared_list
);
619 mutex_unlock(&dpm_list_mtx
);
620 async_synchronize_full();
621 dpm_show_time(starttime
, state
, NULL
);
625 * device_complete - Complete a PM transition for given device.
626 * @dev: Device to handle.
627 * @state: PM transition of the system being carried out.
629 static void device_complete(struct device
*dev
, pm_message_t state
)
633 if (dev
->pwr_domain
) {
634 pm_dev_dbg(dev
, state
, "completing power domain ");
635 if (dev
->pwr_domain
->ops
.complete
)
636 dev
->pwr_domain
->ops
.complete(dev
);
637 } else if (dev
->type
&& dev
->type
->pm
) {
638 pm_dev_dbg(dev
, state
, "completing type ");
639 if (dev
->type
->pm
->complete
)
640 dev
->type
->pm
->complete(dev
);
641 } else if (dev
->class && dev
->class->pm
) {
642 pm_dev_dbg(dev
, state
, "completing class ");
643 if (dev
->class->pm
->complete
)
644 dev
->class->pm
->complete(dev
);
645 } else if (dev
->bus
&& dev
->bus
->pm
) {
646 pm_dev_dbg(dev
, state
, "completing ");
647 if (dev
->bus
->pm
->complete
)
648 dev
->bus
->pm
->complete(dev
);
655 * dpm_complete - Complete a PM transition for all non-sysdev devices.
656 * @state: PM transition of the system being carried out.
658 * Execute the ->complete() callbacks for all devices whose PM status is not
659 * DPM_ON (this allows new devices to be registered).
661 void dpm_complete(pm_message_t state
)
663 struct list_head list
;
667 INIT_LIST_HEAD(&list
);
668 mutex_lock(&dpm_list_mtx
);
669 while (!list_empty(&dpm_prepared_list
)) {
670 struct device
*dev
= to_device(dpm_prepared_list
.prev
);
673 dev
->power
.in_suspend
= false;
674 list_move(&dev
->power
.entry
, &list
);
675 mutex_unlock(&dpm_list_mtx
);
677 device_complete(dev
, state
);
679 mutex_lock(&dpm_list_mtx
);
682 list_splice(&list
, &dpm_list
);
683 mutex_unlock(&dpm_list_mtx
);
687 * dpm_resume_end - Execute "resume" callbacks and complete system transition.
688 * @state: PM transition of the system being carried out.
690 * Execute "resume" callbacks for all devices and complete the PM transition of
693 void dpm_resume_end(pm_message_t state
)
698 EXPORT_SYMBOL_GPL(dpm_resume_end
);
701 /*------------------------- Suspend routines -------------------------*/
704 * resume_event - Return a "resume" message for given "suspend" sleep state.
705 * @sleep_state: PM message representing a sleep state.
707 * Return a PM message representing the resume event corresponding to given
710 static pm_message_t
resume_event(pm_message_t sleep_state
)
712 switch (sleep_state
.event
) {
713 case PM_EVENT_SUSPEND
:
715 case PM_EVENT_FREEZE
:
716 case PM_EVENT_QUIESCE
:
718 case PM_EVENT_HIBERNATE
:
725 * device_suspend_noirq - Execute a "late suspend" callback for given device.
726 * @dev: Device to handle.
727 * @state: PM transition of the system being carried out.
729 * The driver of @dev will not receive interrupts while this function is being
732 static int device_suspend_noirq(struct device
*dev
, pm_message_t state
)
736 if (dev
->pwr_domain
) {
737 pm_dev_dbg(dev
, state
, "LATE power domain ");
738 error
= pm_noirq_op(dev
, &dev
->pwr_domain
->ops
, state
);
741 } else if (dev
->type
&& dev
->type
->pm
) {
742 pm_dev_dbg(dev
, state
, "LATE type ");
743 error
= pm_noirq_op(dev
, dev
->type
->pm
, state
);
746 } else if (dev
->class && dev
->class->pm
) {
747 pm_dev_dbg(dev
, state
, "LATE class ");
748 error
= pm_noirq_op(dev
, dev
->class->pm
, state
);
751 } else if (dev
->bus
&& dev
->bus
->pm
) {
752 pm_dev_dbg(dev
, state
, "LATE ");
753 error
= pm_noirq_op(dev
, dev
->bus
->pm
, state
);
762 * dpm_suspend_noirq - Execute "late suspend" callbacks for non-sysdev devices.
763 * @state: PM transition of the system being carried out.
765 * Prevent device drivers from receiving interrupts and call the "noirq" suspend
766 * handlers for all non-sysdev devices.
768 int dpm_suspend_noirq(pm_message_t state
)
770 ktime_t starttime
= ktime_get();
773 suspend_device_irqs();
774 mutex_lock(&dpm_list_mtx
);
775 while (!list_empty(&dpm_suspended_list
)) {
776 struct device
*dev
= to_device(dpm_suspended_list
.prev
);
779 mutex_unlock(&dpm_list_mtx
);
781 error
= device_suspend_noirq(dev
, state
);
783 mutex_lock(&dpm_list_mtx
);
785 pm_dev_err(dev
, state
, " late", error
);
789 if (!list_empty(&dev
->power
.entry
))
790 list_move(&dev
->power
.entry
, &dpm_noirq_list
);
793 mutex_unlock(&dpm_list_mtx
);
795 dpm_resume_noirq(resume_event(state
));
797 dpm_show_time(starttime
, state
, "late");
800 EXPORT_SYMBOL_GPL(dpm_suspend_noirq
);
803 * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
804 * @dev: Device to suspend.
805 * @state: PM transition of the system being carried out.
806 * @cb: Suspend callback to execute.
808 static int legacy_suspend(struct device
*dev
, pm_message_t state
,
809 int (*cb
)(struct device
*dev
, pm_message_t state
))
814 calltime
= initcall_debug_start(dev
);
816 error
= cb(dev
, state
);
817 suspend_report_result(cb
, error
);
819 initcall_debug_report(dev
, calltime
, error
);
825 * device_suspend - Execute "suspend" callbacks for given device.
826 * @dev: Device to handle.
827 * @state: PM transition of the system being carried out.
828 * @async: If true, the device is being suspended asynchronously.
830 static int __device_suspend(struct device
*dev
, pm_message_t state
, bool async
)
834 dpm_wait_for_children(dev
, async
);
840 if (pm_wakeup_pending()) {
841 async_error
= -EBUSY
;
845 if (dev
->pwr_domain
) {
846 pm_dev_dbg(dev
, state
, "power domain ");
847 error
= pm_op(dev
, &dev
->pwr_domain
->ops
, state
);
851 if (dev
->type
&& dev
->type
->pm
) {
852 pm_dev_dbg(dev
, state
, "type ");
853 error
= pm_op(dev
, dev
->type
->pm
, state
);
858 if (dev
->class->pm
) {
859 pm_dev_dbg(dev
, state
, "class ");
860 error
= pm_op(dev
, dev
->class->pm
, state
);
862 } else if (dev
->class->suspend
) {
863 pm_dev_dbg(dev
, state
, "legacy class ");
864 error
= legacy_suspend(dev
, state
, dev
->class->suspend
);
871 pm_dev_dbg(dev
, state
, "");
872 error
= pm_op(dev
, dev
->bus
->pm
, state
);
873 } else if (dev
->bus
->suspend
) {
874 pm_dev_dbg(dev
, state
, "legacy ");
875 error
= legacy_suspend(dev
, state
, dev
->bus
->suspend
);
881 complete_all(&dev
->power
.completion
);
889 static void async_suspend(void *data
, async_cookie_t cookie
)
891 struct device
*dev
= (struct device
*)data
;
894 error
= __device_suspend(dev
, pm_transition
, true);
896 pm_dev_err(dev
, pm_transition
, " async", error
);
901 static int device_suspend(struct device
*dev
)
903 INIT_COMPLETION(dev
->power
.completion
);
905 if (pm_async_enabled
&& dev
->power
.async_suspend
) {
907 async_schedule(async_suspend
, dev
);
911 return __device_suspend(dev
, pm_transition
, false);
915 * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
916 * @state: PM transition of the system being carried out.
918 int dpm_suspend(pm_message_t state
)
920 ktime_t starttime
= ktime_get();
925 mutex_lock(&dpm_list_mtx
);
926 pm_transition
= state
;
928 while (!list_empty(&dpm_prepared_list
)) {
929 struct device
*dev
= to_device(dpm_prepared_list
.prev
);
932 mutex_unlock(&dpm_list_mtx
);
934 error
= device_suspend(dev
);
936 mutex_lock(&dpm_list_mtx
);
938 pm_dev_err(dev
, state
, "", error
);
942 if (!list_empty(&dev
->power
.entry
))
943 list_move(&dev
->power
.entry
, &dpm_suspended_list
);
948 mutex_unlock(&dpm_list_mtx
);
949 async_synchronize_full();
953 dpm_show_time(starttime
, state
, NULL
);
958 * device_prepare - Prepare a device for system power transition.
959 * @dev: Device to handle.
960 * @state: PM transition of the system being carried out.
962 * Execute the ->prepare() callback(s) for given device. No new children of the
963 * device may be registered after this function has returned.
965 static int device_prepare(struct device
*dev
, pm_message_t state
)
971 if (dev
->pwr_domain
) {
972 pm_dev_dbg(dev
, state
, "preparing power domain ");
973 if (dev
->pwr_domain
->ops
.prepare
)
974 error
= dev
->pwr_domain
->ops
.prepare(dev
);
975 suspend_report_result(dev
->pwr_domain
->ops
.prepare
, error
);
978 } else if (dev
->type
&& dev
->type
->pm
) {
979 pm_dev_dbg(dev
, state
, "preparing type ");
980 if (dev
->type
->pm
->prepare
)
981 error
= dev
->type
->pm
->prepare(dev
);
982 suspend_report_result(dev
->type
->pm
->prepare
, error
);
985 } else if (dev
->class && dev
->class->pm
) {
986 pm_dev_dbg(dev
, state
, "preparing class ");
987 if (dev
->class->pm
->prepare
)
988 error
= dev
->class->pm
->prepare(dev
);
989 suspend_report_result(dev
->class->pm
->prepare
, error
);
992 } else if (dev
->bus
&& dev
->bus
->pm
) {
993 pm_dev_dbg(dev
, state
, "preparing ");
994 if (dev
->bus
->pm
->prepare
)
995 error
= dev
->bus
->pm
->prepare(dev
);
996 suspend_report_result(dev
->bus
->pm
->prepare
, error
);
1006 * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1007 * @state: PM transition of the system being carried out.
1009 * Execute the ->prepare() callback(s) for all devices.
1011 int dpm_prepare(pm_message_t state
)
1017 mutex_lock(&dpm_list_mtx
);
1018 while (!list_empty(&dpm_list
)) {
1019 struct device
*dev
= to_device(dpm_list
.next
);
1022 mutex_unlock(&dpm_list_mtx
);
1024 pm_runtime_get_noresume(dev
);
1025 if (pm_runtime_barrier(dev
) && device_may_wakeup(dev
))
1026 pm_wakeup_event(dev
, 0);
1028 pm_runtime_put_sync(dev
);
1029 error
= pm_wakeup_pending() ?
1030 -EBUSY
: device_prepare(dev
, state
);
1032 mutex_lock(&dpm_list_mtx
);
1034 if (error
== -EAGAIN
) {
1039 printk(KERN_INFO
"PM: Device %s not prepared "
1040 "for power transition: code %d\n",
1041 dev_name(dev
), error
);
1045 dev
->power
.in_suspend
= true;
1046 if (!list_empty(&dev
->power
.entry
))
1047 list_move_tail(&dev
->power
.entry
, &dpm_prepared_list
);
1050 mutex_unlock(&dpm_list_mtx
);
1055 * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1056 * @state: PM transition of the system being carried out.
1058 * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1059 * callbacks for them.
1061 int dpm_suspend_start(pm_message_t state
)
1065 error
= dpm_prepare(state
);
1067 error
= dpm_suspend(state
);
1070 EXPORT_SYMBOL_GPL(dpm_suspend_start
);
1072 void __suspend_report_result(const char *function
, void *fn
, int ret
)
1075 printk(KERN_ERR
"%s(): %pF returns %d\n", function
, fn
, ret
);
1077 EXPORT_SYMBOL_GPL(__suspend_report_result
);
1080 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1081 * @dev: Device to wait for.
1082 * @subordinate: Device that needs to wait for @dev.
1084 int device_pm_wait_for_dev(struct device
*subordinate
, struct device
*dev
)
1086 dpm_wait(dev
, subordinate
->power
.async_suspend
);
1089 EXPORT_SYMBOL_GPL(device_pm_wait_for_dev
);