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/export.h>
23 #include <linux/mutex.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/resume-trace.h>
27 #include <linux/interrupt.h>
28 #include <linux/sched.h>
29 #include <linux/async.h>
30 #include <linux/suspend.h>
35 typedef int (*pm_callback_t)(struct device *);
38 * The entries in the dpm_list list are in a depth first order, simply
39 * because children are guaranteed to be discovered after parents, and
40 * are inserted at the back of the list on discovery.
42 * Since device_pm_add() may be called with a device lock held,
43 * we must never try to acquire a device lock while holding
48 LIST_HEAD(dpm_prepared_list);
49 LIST_HEAD(dpm_suspended_list);
50 LIST_HEAD(dpm_late_early_list);
51 LIST_HEAD(dpm_noirq_list);
53 struct suspend_stats suspend_stats;
54 static DEFINE_MUTEX(dpm_list_mtx);
55 static pm_message_t pm_transition;
57 static int async_error;
60 * device_pm_init - Initialize the PM-related part of a device object.
61 * @dev: Device object being initialized.
63 void device_pm_init(struct device *dev)
65 dev->power.is_prepared = false;
66 dev->power.is_suspended = false;
67 init_completion(&dev->power.completion);
68 complete_all(&dev->power.completion);
69 dev->power.wakeup = NULL;
70 spin_lock_init(&dev->power.lock);
72 INIT_LIST_HEAD(&dev->power.entry);
73 dev->power.power_state = PMSG_INVALID;
77 * device_pm_lock - Lock the list of active devices used by the PM core.
79 void device_pm_lock(void)
81 mutex_lock(&dpm_list_mtx);
85 * device_pm_unlock - Unlock the list of active devices used by the PM core.
87 void device_pm_unlock(void)
89 mutex_unlock(&dpm_list_mtx);
93 * device_pm_add - Add a device to the PM core's list of active devices.
94 * @dev: Device to add to the list.
96 void device_pm_add(struct device *dev)
98 pr_debug("PM: Adding info for %s:%s\n",
99 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
100 mutex_lock(&dpm_list_mtx);
101 if (dev->parent && dev->parent->power.is_prepared)
102 dev_warn(dev, "parent %s should not be sleeping\n",
103 dev_name(dev->parent));
104 list_add_tail(&dev->power.entry, &dpm_list);
105 dev_pm_qos_constraints_init(dev);
106 mutex_unlock(&dpm_list_mtx);
110 * device_pm_remove - Remove a device from the PM core's list of active devices.
111 * @dev: Device to be removed from the list.
113 void device_pm_remove(struct device *dev)
115 pr_debug("PM: Removing info for %s:%s\n",
116 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
117 complete_all(&dev->power.completion);
118 mutex_lock(&dpm_list_mtx);
119 dev_pm_qos_constraints_destroy(dev);
120 list_del_init(&dev->power.entry);
121 mutex_unlock(&dpm_list_mtx);
122 device_wakeup_disable(dev);
123 pm_runtime_remove(dev);
127 * device_pm_move_before - Move device in the PM core's list of active devices.
128 * @deva: Device to move in dpm_list.
129 * @devb: Device @deva should come before.
131 void device_pm_move_before(struct device *deva, struct device *devb)
133 pr_debug("PM: Moving %s:%s before %s:%s\n",
134 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
135 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
136 /* Delete deva from dpm_list and reinsert before devb. */
137 list_move_tail(&deva->power.entry, &devb->power.entry);
141 * device_pm_move_after - Move device in the PM core's list of active devices.
142 * @deva: Device to move in dpm_list.
143 * @devb: Device @deva should come after.
145 void device_pm_move_after(struct device *deva, struct device *devb)
147 pr_debug("PM: Moving %s:%s after %s:%s\n",
148 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
149 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
150 /* Delete deva from dpm_list and reinsert after devb. */
151 list_move(&deva->power.entry, &devb->power.entry);
155 * device_pm_move_last - Move device to end of the PM core's list of devices.
156 * @dev: Device to move in dpm_list.
158 void device_pm_move_last(struct device *dev)
160 pr_debug("PM: Moving %s:%s to end of list\n",
161 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
162 list_move_tail(&dev->power.entry, &dpm_list);
165 static ktime_t initcall_debug_start(struct device *dev)
167 ktime_t calltime = ktime_set(0, 0);
169 if (initcall_debug) {
170 pr_info("calling %s+ @ %i, parent: %s\n",
171 dev_name(dev), task_pid_nr(current),
172 dev->parent ? dev_name(dev->parent) : "none");
173 calltime = ktime_get();
179 static void initcall_debug_report(struct device *dev, ktime_t calltime,
182 ktime_t delta, rettime;
184 if (initcall_debug) {
185 rettime = ktime_get();
186 delta = ktime_sub(rettime, calltime);
187 pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
188 error, (unsigned long long)ktime_to_ns(delta) >> 10);
193 * dpm_wait - Wait for a PM operation to complete.
194 * @dev: Device to wait for.
195 * @async: If unset, wait only if the device's power.async_suspend flag is set.
197 static void dpm_wait(struct device *dev, bool async)
202 if (async || (pm_async_enabled && dev->power.async_suspend))
203 wait_for_completion(&dev->power.completion);
206 static int dpm_wait_fn(struct device *dev, void *async_ptr)
208 dpm_wait(dev, *((bool *)async_ptr));
212 static void dpm_wait_for_children(struct device *dev, bool async)
214 device_for_each_child(dev, &async, dpm_wait_fn);
218 * pm_op - Return the PM operation appropriate for given PM event.
219 * @ops: PM operations to choose from.
220 * @state: PM transition of the system being carried out.
222 static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
224 switch (state.event) {
225 #ifdef CONFIG_SUSPEND
226 case PM_EVENT_SUSPEND:
228 case PM_EVENT_RESUME:
230 #endif /* CONFIG_SUSPEND */
231 #ifdef CONFIG_HIBERNATE_CALLBACKS
232 case PM_EVENT_FREEZE:
233 case PM_EVENT_QUIESCE:
235 case PM_EVENT_HIBERNATE:
236 return ops->poweroff;
238 case PM_EVENT_RECOVER:
241 case PM_EVENT_RESTORE:
243 #endif /* CONFIG_HIBERNATE_CALLBACKS */
250 * pm_late_early_op - Return the PM operation appropriate for given PM event.
251 * @ops: PM operations to choose from.
252 * @state: PM transition of the system being carried out.
254 * Runtime PM is disabled for @dev while this function is being executed.
256 static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
259 switch (state.event) {
260 #ifdef CONFIG_SUSPEND
261 case PM_EVENT_SUSPEND:
262 return ops->suspend_late;
263 case PM_EVENT_RESUME:
264 return ops->resume_early;
265 #endif /* CONFIG_SUSPEND */
266 #ifdef CONFIG_HIBERNATE_CALLBACKS
267 case PM_EVENT_FREEZE:
268 case PM_EVENT_QUIESCE:
269 return ops->freeze_late;
270 case PM_EVENT_HIBERNATE:
271 return ops->poweroff_late;
273 case PM_EVENT_RECOVER:
274 return ops->thaw_early;
275 case PM_EVENT_RESTORE:
276 return ops->restore_early;
277 #endif /* CONFIG_HIBERNATE_CALLBACKS */
284 * pm_noirq_op - Return the PM operation appropriate for given PM event.
285 * @ops: PM operations to choose from.
286 * @state: PM transition of the system being carried out.
288 * The driver of @dev will not receive interrupts while this function is being
291 static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
293 switch (state.event) {
294 #ifdef CONFIG_SUSPEND
295 case PM_EVENT_SUSPEND:
296 return ops->suspend_noirq;
297 case PM_EVENT_RESUME:
298 return ops->resume_noirq;
299 #endif /* CONFIG_SUSPEND */
300 #ifdef CONFIG_HIBERNATE_CALLBACKS
301 case PM_EVENT_FREEZE:
302 case PM_EVENT_QUIESCE:
303 return ops->freeze_noirq;
304 case PM_EVENT_HIBERNATE:
305 return ops->poweroff_noirq;
307 case PM_EVENT_RECOVER:
308 return ops->thaw_noirq;
309 case PM_EVENT_RESTORE:
310 return ops->restore_noirq;
311 #endif /* CONFIG_HIBERNATE_CALLBACKS */
317 static char *pm_verb(int event)
320 case PM_EVENT_SUSPEND:
322 case PM_EVENT_RESUME:
324 case PM_EVENT_FREEZE:
326 case PM_EVENT_QUIESCE:
328 case PM_EVENT_HIBERNATE:
332 case PM_EVENT_RESTORE:
334 case PM_EVENT_RECOVER:
337 return "(unknown PM event)";
341 static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
343 dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
344 ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
345 ", may wakeup" : "");
348 static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
351 printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
352 dev_name(dev), pm_verb(state.event), info, error);
355 static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info)
361 calltime = ktime_get();
362 usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
363 do_div(usecs64, NSEC_PER_USEC);
367 pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n",
368 info ?: "", info ? " " : "", pm_verb(state.event),
369 usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
372 static int dpm_run_callback(pm_callback_t cb, struct device *dev,
373 pm_message_t state, char *info)
381 calltime = initcall_debug_start(dev);
383 pm_dev_dbg(dev, state, info);
385 suspend_report_result(cb, error);
387 initcall_debug_report(dev, calltime, error);
392 /*------------------------- Resume routines -------------------------*/
395 * device_resume_noirq - Execute an "early resume" callback for given device.
396 * @dev: Device to handle.
397 * @state: PM transition of the system being carried out.
399 * The driver of @dev will not receive interrupts while this function is being
402 static int device_resume_noirq(struct device *dev, pm_message_t state)
404 pm_callback_t callback = NULL;
411 if (dev->pm_domain) {
412 info = "noirq power domain ";
413 callback = pm_noirq_op(&dev->pm_domain->ops, state);
414 } else if (dev->type && dev->type->pm) {
415 info = "noirq type ";
416 callback = pm_noirq_op(dev->type->pm, state);
417 } else if (dev->class && dev->class->pm) {
418 info = "noirq class ";
419 callback = pm_noirq_op(dev->class->pm, state);
420 } else if (dev->bus && dev->bus->pm) {
422 callback = pm_noirq_op(dev->bus->pm, state);
425 if (!callback && dev->driver && dev->driver->pm) {
426 info = "noirq driver ";
427 callback = pm_noirq_op(dev->driver->pm, state);
430 error = dpm_run_callback(callback, dev, state, info);
437 * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
438 * @state: PM transition of the system being carried out.
440 * Call the "noirq" resume handlers for all devices in dpm_noirq_list and
441 * enable device drivers to receive interrupts.
443 static void dpm_resume_noirq(pm_message_t state)
445 ktime_t starttime = ktime_get();
447 mutex_lock(&dpm_list_mtx);
448 while (!list_empty(&dpm_noirq_list)) {
449 struct device *dev = to_device(dpm_noirq_list.next);
453 list_move_tail(&dev->power.entry, &dpm_late_early_list);
454 mutex_unlock(&dpm_list_mtx);
456 error = device_resume_noirq(dev, state);
458 suspend_stats.failed_resume_noirq++;
459 dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
460 dpm_save_failed_dev(dev_name(dev));
461 pm_dev_err(dev, state, " noirq", error);
464 mutex_lock(&dpm_list_mtx);
467 mutex_unlock(&dpm_list_mtx);
468 dpm_show_time(starttime, state, "noirq");
469 resume_device_irqs();
473 * device_resume_early - Execute an "early resume" callback for given device.
474 * @dev: Device to handle.
475 * @state: PM transition of the system being carried out.
477 * Runtime PM is disabled for @dev while this function is being executed.
479 static int device_resume_early(struct device *dev, pm_message_t state)
481 pm_callback_t callback = NULL;
488 if (dev->pm_domain) {
489 info = "early power domain ";
490 callback = pm_late_early_op(&dev->pm_domain->ops, state);
491 } else if (dev->type && dev->type->pm) {
492 info = "early type ";
493 callback = pm_late_early_op(dev->type->pm, state);
494 } else if (dev->class && dev->class->pm) {
495 info = "early class ";
496 callback = pm_late_early_op(dev->class->pm, state);
497 } else if (dev->bus && dev->bus->pm) {
499 callback = pm_late_early_op(dev->bus->pm, state);
502 if (!callback && dev->driver && dev->driver->pm) {
503 info = "early driver ";
504 callback = pm_late_early_op(dev->driver->pm, state);
507 error = dpm_run_callback(callback, dev, state, info);
514 * dpm_resume_early - Execute "early resume" callbacks for all devices.
515 * @state: PM transition of the system being carried out.
517 static void dpm_resume_early(pm_message_t state)
519 ktime_t starttime = ktime_get();
521 mutex_lock(&dpm_list_mtx);
522 while (!list_empty(&dpm_late_early_list)) {
523 struct device *dev = to_device(dpm_late_early_list.next);
527 list_move_tail(&dev->power.entry, &dpm_suspended_list);
528 mutex_unlock(&dpm_list_mtx);
530 error = device_resume_early(dev, state);
532 suspend_stats.failed_resume_early++;
533 dpm_save_failed_step(SUSPEND_RESUME_EARLY);
534 dpm_save_failed_dev(dev_name(dev));
535 pm_dev_err(dev, state, " early", error);
538 mutex_lock(&dpm_list_mtx);
541 mutex_unlock(&dpm_list_mtx);
542 dpm_show_time(starttime, state, "early");
546 * dpm_resume_start - Execute "noirq" and "early" device callbacks.
547 * @state: PM transition of the system being carried out.
549 void dpm_resume_start(pm_message_t state)
551 dpm_resume_noirq(state);
552 dpm_resume_early(state);
554 EXPORT_SYMBOL_GPL(dpm_resume_start);
557 * device_resume - Execute "resume" callbacks for given device.
558 * @dev: Device to handle.
559 * @state: PM transition of the system being carried out.
560 * @async: If true, the device is being resumed asynchronously.
562 static int device_resume(struct device *dev, pm_message_t state, bool async)
564 pm_callback_t callback = NULL;
572 dpm_wait(dev->parent, async);
576 * This is a fib. But we'll allow new children to be added below
577 * a resumed device, even if the device hasn't been completed yet.
579 dev->power.is_prepared = false;
581 if (!dev->power.is_suspended)
584 pm_runtime_enable(dev);
587 if (dev->pm_domain) {
588 info = "power domain ";
589 callback = pm_op(&dev->pm_domain->ops, state);
593 if (dev->type && dev->type->pm) {
595 callback = pm_op(dev->type->pm, state);
600 if (dev->class->pm) {
602 callback = pm_op(dev->class->pm, state);
604 } else if (dev->class->resume) {
605 info = "legacy class ";
606 callback = dev->class->resume;
614 callback = pm_op(dev->bus->pm, state);
615 } else if (dev->bus->resume) {
616 info = "legacy bus ";
617 callback = dev->bus->resume;
623 if (!callback && dev->driver && dev->driver->pm) {
625 callback = pm_op(dev->driver->pm, state);
629 error = dpm_run_callback(callback, dev, state, info);
630 dev->power.is_suspended = false;
634 complete_all(&dev->power.completion);
639 pm_runtime_put_sync(dev);
644 static void async_resume(void *data, async_cookie_t cookie)
646 struct device *dev = (struct device *)data;
649 error = device_resume(dev, pm_transition, true);
651 pm_dev_err(dev, pm_transition, " async", error);
655 static bool is_async(struct device *dev)
657 return dev->power.async_suspend && pm_async_enabled
658 && !pm_trace_is_enabled();
662 * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
663 * @state: PM transition of the system being carried out.
665 * Execute the appropriate "resume" callback for all devices whose status
666 * indicates that they are suspended.
668 void dpm_resume(pm_message_t state)
671 ktime_t starttime = ktime_get();
675 mutex_lock(&dpm_list_mtx);
676 pm_transition = state;
679 list_for_each_entry(dev, &dpm_suspended_list, power.entry) {
680 INIT_COMPLETION(dev->power.completion);
683 async_schedule(async_resume, dev);
687 while (!list_empty(&dpm_suspended_list)) {
688 dev = to_device(dpm_suspended_list.next);
690 if (!is_async(dev)) {
693 mutex_unlock(&dpm_list_mtx);
695 error = device_resume(dev, state, false);
697 suspend_stats.failed_resume++;
698 dpm_save_failed_step(SUSPEND_RESUME);
699 dpm_save_failed_dev(dev_name(dev));
700 pm_dev_err(dev, state, "", error);
703 mutex_lock(&dpm_list_mtx);
705 if (!list_empty(&dev->power.entry))
706 list_move_tail(&dev->power.entry, &dpm_prepared_list);
709 mutex_unlock(&dpm_list_mtx);
710 async_synchronize_full();
711 dpm_show_time(starttime, state, NULL);
715 * device_complete - Complete a PM transition for given device.
716 * @dev: Device to handle.
717 * @state: PM transition of the system being carried out.
719 static void device_complete(struct device *dev, pm_message_t state)
721 void (*callback)(struct device *) = NULL;
726 if (dev->pm_domain) {
727 info = "completing power domain ";
728 callback = dev->pm_domain->ops.complete;
729 } else if (dev->type && dev->type->pm) {
730 info = "completing type ";
731 callback = dev->type->pm->complete;
732 } else if (dev->class && dev->class->pm) {
733 info = "completing class ";
734 callback = dev->class->pm->complete;
735 } else if (dev->bus && dev->bus->pm) {
736 info = "completing bus ";
737 callback = dev->bus->pm->complete;
740 if (!callback && dev->driver && dev->driver->pm) {
741 info = "completing driver ";
742 callback = dev->driver->pm->complete;
746 pm_dev_dbg(dev, state, info);
754 * dpm_complete - Complete a PM transition for all non-sysdev devices.
755 * @state: PM transition of the system being carried out.
757 * Execute the ->complete() callbacks for all devices whose PM status is not
758 * DPM_ON (this allows new devices to be registered).
760 void dpm_complete(pm_message_t state)
762 struct list_head list;
766 INIT_LIST_HEAD(&list);
767 mutex_lock(&dpm_list_mtx);
768 while (!list_empty(&dpm_prepared_list)) {
769 struct device *dev = to_device(dpm_prepared_list.prev);
772 dev->power.is_prepared = false;
773 list_move(&dev->power.entry, &list);
774 mutex_unlock(&dpm_list_mtx);
776 device_complete(dev, state);
778 mutex_lock(&dpm_list_mtx);
781 list_splice(&list, &dpm_list);
782 mutex_unlock(&dpm_list_mtx);
786 * dpm_resume_end - Execute "resume" callbacks and complete system transition.
787 * @state: PM transition of the system being carried out.
789 * Execute "resume" callbacks for all devices and complete the PM transition of
792 void dpm_resume_end(pm_message_t state)
797 EXPORT_SYMBOL_GPL(dpm_resume_end);
800 /*------------------------- Suspend routines -------------------------*/
803 * resume_event - Return a "resume" message for given "suspend" sleep state.
804 * @sleep_state: PM message representing a sleep state.
806 * Return a PM message representing the resume event corresponding to given
809 static pm_message_t resume_event(pm_message_t sleep_state)
811 switch (sleep_state.event) {
812 case PM_EVENT_SUSPEND:
814 case PM_EVENT_FREEZE:
815 case PM_EVENT_QUIESCE:
817 case PM_EVENT_HIBERNATE:
824 * device_suspend_noirq - Execute a "late suspend" callback for given device.
825 * @dev: Device to handle.
826 * @state: PM transition of the system being carried out.
828 * The driver of @dev will not receive interrupts while this function is being
831 static int device_suspend_noirq(struct device *dev, pm_message_t state)
833 pm_callback_t callback = NULL;
836 if (dev->pm_domain) {
837 info = "noirq power domain ";
838 callback = pm_noirq_op(&dev->pm_domain->ops, state);
839 } else if (dev->type && dev->type->pm) {
840 info = "noirq type ";
841 callback = pm_noirq_op(dev->type->pm, state);
842 } else if (dev->class && dev->class->pm) {
843 info = "noirq class ";
844 callback = pm_noirq_op(dev->class->pm, state);
845 } else if (dev->bus && dev->bus->pm) {
847 callback = pm_noirq_op(dev->bus->pm, state);
850 if (!callback && dev->driver && dev->driver->pm) {
851 info = "noirq driver ";
852 callback = pm_noirq_op(dev->driver->pm, state);
855 return dpm_run_callback(callback, dev, state, info);
859 * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
860 * @state: PM transition of the system being carried out.
862 * Prevent device drivers from receiving interrupts and call the "noirq" suspend
863 * handlers for all non-sysdev devices.
865 static int dpm_suspend_noirq(pm_message_t state)
867 ktime_t starttime = ktime_get();
870 suspend_device_irqs();
871 mutex_lock(&dpm_list_mtx);
872 while (!list_empty(&dpm_late_early_list)) {
873 struct device *dev = to_device(dpm_late_early_list.prev);
876 mutex_unlock(&dpm_list_mtx);
878 error = device_suspend_noirq(dev, state);
880 mutex_lock(&dpm_list_mtx);
882 pm_dev_err(dev, state, " noirq", error);
883 suspend_stats.failed_suspend_noirq++;
884 dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
885 dpm_save_failed_dev(dev_name(dev));
889 if (!list_empty(&dev->power.entry))
890 list_move(&dev->power.entry, &dpm_noirq_list);
893 if (pm_wakeup_pending()) {
898 mutex_unlock(&dpm_list_mtx);
900 dpm_resume_noirq(resume_event(state));
902 dpm_show_time(starttime, state, "noirq");
907 * device_suspend_late - Execute a "late suspend" callback for given device.
908 * @dev: Device to handle.
909 * @state: PM transition of the system being carried out.
911 * Runtime PM is disabled for @dev while this function is being executed.
913 static int device_suspend_late(struct device *dev, pm_message_t state)
915 pm_callback_t callback = NULL;
918 if (dev->pm_domain) {
919 info = "late power domain ";
920 callback = pm_late_early_op(&dev->pm_domain->ops, state);
921 } else if (dev->type && dev->type->pm) {
923 callback = pm_late_early_op(dev->type->pm, state);
924 } else if (dev->class && dev->class->pm) {
925 info = "late class ";
926 callback = pm_late_early_op(dev->class->pm, state);
927 } else if (dev->bus && dev->bus->pm) {
929 callback = pm_late_early_op(dev->bus->pm, state);
932 if (!callback && dev->driver && dev->driver->pm) {
933 info = "late driver ";
934 callback = pm_late_early_op(dev->driver->pm, state);
937 return dpm_run_callback(callback, dev, state, info);
941 * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
942 * @state: PM transition of the system being carried out.
944 static int dpm_suspend_late(pm_message_t state)
946 ktime_t starttime = ktime_get();
949 mutex_lock(&dpm_list_mtx);
950 while (!list_empty(&dpm_suspended_list)) {
951 struct device *dev = to_device(dpm_suspended_list.prev);
954 mutex_unlock(&dpm_list_mtx);
956 error = device_suspend_late(dev, state);
958 mutex_lock(&dpm_list_mtx);
960 pm_dev_err(dev, state, " late", error);
961 suspend_stats.failed_suspend_late++;
962 dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
963 dpm_save_failed_dev(dev_name(dev));
967 if (!list_empty(&dev->power.entry))
968 list_move(&dev->power.entry, &dpm_late_early_list);
971 if (pm_wakeup_pending()) {
976 mutex_unlock(&dpm_list_mtx);
978 dpm_resume_early(resume_event(state));
980 dpm_show_time(starttime, state, "late");
986 * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
987 * @state: PM transition of the system being carried out.
989 int dpm_suspend_end(pm_message_t state)
991 int error = dpm_suspend_late(state);
993 return error ? : dpm_suspend_noirq(state);
995 EXPORT_SYMBOL_GPL(dpm_suspend_end);
998 * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
999 * @dev: Device to suspend.
1000 * @state: PM transition of the system being carried out.
1001 * @cb: Suspend callback to execute.
1003 static int legacy_suspend(struct device *dev, pm_message_t state,
1004 int (*cb)(struct device *dev, pm_message_t state))
1009 calltime = initcall_debug_start(dev);
1011 error = cb(dev, state);
1012 suspend_report_result(cb, error);
1014 initcall_debug_report(dev, calltime, error);
1020 * device_suspend - Execute "suspend" callbacks for given device.
1021 * @dev: Device to handle.
1022 * @state: PM transition of the system being carried out.
1023 * @async: If true, the device is being suspended asynchronously.
1025 static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1027 pm_callback_t callback = NULL;
1031 dpm_wait_for_children(dev, async);
1036 pm_runtime_get_noresume(dev);
1037 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
1038 pm_wakeup_event(dev, 0);
1040 if (pm_wakeup_pending()) {
1041 pm_runtime_put_sync(dev);
1042 async_error = -EBUSY;
1048 if (dev->pm_domain) {
1049 info = "power domain ";
1050 callback = pm_op(&dev->pm_domain->ops, state);
1054 if (dev->type && dev->type->pm) {
1056 callback = pm_op(dev->type->pm, state);
1061 if (dev->class->pm) {
1063 callback = pm_op(dev->class->pm, state);
1065 } else if (dev->class->suspend) {
1066 pm_dev_dbg(dev, state, "legacy class ");
1067 error = legacy_suspend(dev, state, dev->class->suspend);
1075 callback = pm_op(dev->bus->pm, state);
1076 } else if (dev->bus->suspend) {
1077 pm_dev_dbg(dev, state, "legacy bus ");
1078 error = legacy_suspend(dev, state, dev->bus->suspend);
1084 if (!callback && dev->driver && dev->driver->pm) {
1086 callback = pm_op(dev->driver->pm, state);
1089 error = dpm_run_callback(callback, dev, state, info);
1093 dev->power.is_suspended = true;
1094 if (dev->power.wakeup_path
1095 && dev->parent && !dev->parent->power.ignore_children)
1096 dev->parent->power.wakeup_path = true;
1100 complete_all(&dev->power.completion);
1103 pm_runtime_put_sync(dev);
1104 async_error = error;
1105 } else if (dev->power.is_suspended) {
1106 __pm_runtime_disable(dev, false);
1112 static void async_suspend(void *data, async_cookie_t cookie)
1114 struct device *dev = (struct device *)data;
1117 error = __device_suspend(dev, pm_transition, true);
1119 dpm_save_failed_dev(dev_name(dev));
1120 pm_dev_err(dev, pm_transition, " async", error);
1126 static int device_suspend(struct device *dev)
1128 INIT_COMPLETION(dev->power.completion);
1130 if (pm_async_enabled && dev->power.async_suspend) {
1132 async_schedule(async_suspend, dev);
1136 return __device_suspend(dev, pm_transition, false);
1140 * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
1141 * @state: PM transition of the system being carried out.
1143 int dpm_suspend(pm_message_t state)
1145 ktime_t starttime = ktime_get();
1150 mutex_lock(&dpm_list_mtx);
1151 pm_transition = state;
1153 while (!list_empty(&dpm_prepared_list)) {
1154 struct device *dev = to_device(dpm_prepared_list.prev);
1157 mutex_unlock(&dpm_list_mtx);
1159 error = device_suspend(dev);
1161 mutex_lock(&dpm_list_mtx);
1163 pm_dev_err(dev, state, "", error);
1164 dpm_save_failed_dev(dev_name(dev));
1168 if (!list_empty(&dev->power.entry))
1169 list_move(&dev->power.entry, &dpm_suspended_list);
1174 mutex_unlock(&dpm_list_mtx);
1175 async_synchronize_full();
1177 error = async_error;
1179 suspend_stats.failed_suspend++;
1180 dpm_save_failed_step(SUSPEND_SUSPEND);
1182 dpm_show_time(starttime, state, NULL);
1187 * device_prepare - Prepare a device for system power transition.
1188 * @dev: Device to handle.
1189 * @state: PM transition of the system being carried out.
1191 * Execute the ->prepare() callback(s) for given device. No new children of the
1192 * device may be registered after this function has returned.
1194 static int device_prepare(struct device *dev, pm_message_t state)
1196 int (*callback)(struct device *) = NULL;
1202 dev->power.wakeup_path = device_may_wakeup(dev);
1204 if (dev->pm_domain) {
1205 info = "preparing power domain ";
1206 callback = dev->pm_domain->ops.prepare;
1207 } else if (dev->type && dev->type->pm) {
1208 info = "preparing type ";
1209 callback = dev->type->pm->prepare;
1210 } else if (dev->class && dev->class->pm) {
1211 info = "preparing class ";
1212 callback = dev->class->pm->prepare;
1213 } else if (dev->bus && dev->bus->pm) {
1214 info = "preparing bus ";
1215 callback = dev->bus->pm->prepare;
1218 if (!callback && dev->driver && dev->driver->pm) {
1219 info = "preparing driver ";
1220 callback = dev->driver->pm->prepare;
1224 error = callback(dev);
1225 suspend_report_result(callback, error);
1234 * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1235 * @state: PM transition of the system being carried out.
1237 * Execute the ->prepare() callback(s) for all devices.
1239 int dpm_prepare(pm_message_t state)
1245 mutex_lock(&dpm_list_mtx);
1246 while (!list_empty(&dpm_list)) {
1247 struct device *dev = to_device(dpm_list.next);
1250 mutex_unlock(&dpm_list_mtx);
1252 error = device_prepare(dev, state);
1254 mutex_lock(&dpm_list_mtx);
1256 if (error == -EAGAIN) {
1261 printk(KERN_INFO "PM: Device %s not prepared "
1262 "for power transition: code %d\n",
1263 dev_name(dev), error);
1267 dev->power.is_prepared = true;
1268 if (!list_empty(&dev->power.entry))
1269 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1272 mutex_unlock(&dpm_list_mtx);
1277 * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1278 * @state: PM transition of the system being carried out.
1280 * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1281 * callbacks for them.
1283 int dpm_suspend_start(pm_message_t state)
1287 error = dpm_prepare(state);
1289 suspend_stats.failed_prepare++;
1290 dpm_save_failed_step(SUSPEND_PREPARE);
1292 error = dpm_suspend(state);
1295 EXPORT_SYMBOL_GPL(dpm_suspend_start);
1297 void __suspend_report_result(const char *function, void *fn, int ret)
1300 printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
1302 EXPORT_SYMBOL_GPL(__suspend_report_result);
1305 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1306 * @dev: Device to wait for.
1307 * @subordinate: Device that needs to wait for @dev.
1309 int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
1311 dpm_wait(dev, subordinate->power.async_suspend);
1314 EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);