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/pm-trace.h>
27 #include <linux/pm_wakeirq.h>
28 #include <linux/interrupt.h>
29 #include <linux/sched.h>
30 #include <linux/async.h>
31 #include <linux/suspend.h>
32 #include <trace/events/power.h>
33 #include <linux/cpufreq.h>
34 #include <linux/cpuidle.h>
35 #include <linux/timer.h>
40 typedef int (*pm_callback_t)(struct device *);
43 * The entries in the dpm_list list are in a depth first order, simply
44 * because children are guaranteed to be discovered after parents, and
45 * are inserted at the back of the list on discovery.
47 * Since device_pm_add() may be called with a device lock held,
48 * we must never try to acquire a device lock while holding
53 static LIST_HEAD(dpm_prepared_list);
54 static LIST_HEAD(dpm_suspended_list);
55 static LIST_HEAD(dpm_late_early_list);
56 static LIST_HEAD(dpm_noirq_list);
58 struct suspend_stats suspend_stats;
59 static DEFINE_MUTEX(dpm_list_mtx);
60 static pm_message_t pm_transition;
62 static void dpm_drv_timeout(unsigned long data);
63 struct dpm_drv_wd_data {
65 struct task_struct *tsk;
68 static int async_error;
70 static char *pm_verb(int event)
73 case PM_EVENT_SUSPEND:
79 case PM_EVENT_QUIESCE:
81 case PM_EVENT_HIBERNATE:
85 case PM_EVENT_RESTORE:
87 case PM_EVENT_RECOVER:
90 return "(unknown PM event)";
95 * device_pm_sleep_init - Initialize system suspend-related device fields.
96 * @dev: Device object being initialized.
98 void device_pm_sleep_init(struct device *dev)
100 dev->power.is_prepared = false;
101 dev->power.is_suspended = false;
102 dev->power.is_noirq_suspended = false;
103 dev->power.is_late_suspended = false;
104 init_completion(&dev->power.completion);
105 complete_all(&dev->power.completion);
106 dev->power.wakeup = NULL;
107 INIT_LIST_HEAD(&dev->power.entry);
111 * device_pm_lock - Lock the list of active devices used by the PM core.
113 void device_pm_lock(void)
115 mutex_lock(&dpm_list_mtx);
119 * device_pm_unlock - Unlock the list of active devices used by the PM core.
121 void device_pm_unlock(void)
123 mutex_unlock(&dpm_list_mtx);
127 * device_pm_add - Add a device to the PM core's list of active devices.
128 * @dev: Device to add to the list.
130 void device_pm_add(struct device *dev)
132 pr_debug("PM: Adding info for %s:%s\n",
133 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
134 mutex_lock(&dpm_list_mtx);
135 if (dev->parent && dev->parent->power.is_prepared)
136 dev_warn(dev, "parent %s should not be sleeping\n",
137 dev_name(dev->parent));
138 list_add_tail(&dev->power.entry, &dpm_list);
139 mutex_unlock(&dpm_list_mtx);
143 * device_pm_remove - Remove a device from the PM core's list of active devices.
144 * @dev: Device to be removed from the list.
146 void device_pm_remove(struct device *dev)
148 pr_debug("PM: Removing info for %s:%s\n",
149 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
150 complete_all(&dev->power.completion);
151 mutex_lock(&dpm_list_mtx);
152 list_del_init(&dev->power.entry);
153 mutex_unlock(&dpm_list_mtx);
154 device_wakeup_disable(dev);
155 pm_runtime_remove(dev);
159 * device_pm_move_before - Move device in the PM core's list of active devices.
160 * @deva: Device to move in dpm_list.
161 * @devb: Device @deva should come before.
163 void device_pm_move_before(struct device *deva, struct device *devb)
165 pr_debug("PM: Moving %s:%s before %s:%s\n",
166 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
167 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
168 /* Delete deva from dpm_list and reinsert before devb. */
169 list_move_tail(&deva->power.entry, &devb->power.entry);
173 * device_pm_move_after - Move device in the PM core's list of active devices.
174 * @deva: Device to move in dpm_list.
175 * @devb: Device @deva should come after.
177 void device_pm_move_after(struct device *deva, struct device *devb)
179 pr_debug("PM: Moving %s:%s after %s:%s\n",
180 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
181 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
182 /* Delete deva from dpm_list and reinsert after devb. */
183 list_move(&deva->power.entry, &devb->power.entry);
187 * device_pm_move_last - Move device to end of the PM core's list of devices.
188 * @dev: Device to move in dpm_list.
190 void device_pm_move_last(struct device *dev)
192 pr_debug("PM: Moving %s:%s to end of list\n",
193 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
194 list_move_tail(&dev->power.entry, &dpm_list);
197 static ktime_t initcall_debug_start(struct device *dev)
199 ktime_t calltime = ktime_set(0, 0);
201 if (pm_print_times_enabled) {
202 pr_info("calling %s+ @ %i, parent: %s\n",
203 dev_name(dev), task_pid_nr(current),
204 dev->parent ? dev_name(dev->parent) : "none");
205 calltime = ktime_get();
211 static void initcall_debug_report(struct device *dev, ktime_t calltime,
212 int error, pm_message_t state, char *info)
217 rettime = ktime_get();
218 nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime));
220 if (pm_print_times_enabled) {
221 pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
222 error, (unsigned long long)nsecs >> 10);
227 * dpm_wait - Wait for a PM operation to complete.
228 * @dev: Device to wait for.
229 * @async: If unset, wait only if the device's power.async_suspend flag is set.
231 static void dpm_wait(struct device *dev, bool async)
236 if (async || (pm_async_enabled && dev->power.async_suspend))
237 wait_for_completion(&dev->power.completion);
240 static int dpm_wait_fn(struct device *dev, void *async_ptr)
242 dpm_wait(dev, *((bool *)async_ptr));
246 static void dpm_wait_for_children(struct device *dev, bool async)
248 device_for_each_child(dev, &async, dpm_wait_fn);
252 * pm_op - Return the PM operation appropriate for given PM event.
253 * @ops: PM operations to choose from.
254 * @state: PM transition of the system being carried out.
256 static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
258 switch (state.event) {
259 #ifdef CONFIG_SUSPEND
260 case PM_EVENT_SUSPEND:
262 case PM_EVENT_RESUME:
264 #endif /* CONFIG_SUSPEND */
265 #ifdef CONFIG_HIBERNATE_CALLBACKS
266 case PM_EVENT_FREEZE:
267 case PM_EVENT_QUIESCE:
269 case PM_EVENT_HIBERNATE:
270 return ops->poweroff;
272 case PM_EVENT_RECOVER:
275 case PM_EVENT_RESTORE:
277 #endif /* CONFIG_HIBERNATE_CALLBACKS */
284 * pm_late_early_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 * Runtime PM is disabled for @dev while this function is being executed.
290 static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
293 switch (state.event) {
294 #ifdef CONFIG_SUSPEND
295 case PM_EVENT_SUSPEND:
296 return ops->suspend_late;
297 case PM_EVENT_RESUME:
298 return ops->resume_early;
299 #endif /* CONFIG_SUSPEND */
300 #ifdef CONFIG_HIBERNATE_CALLBACKS
301 case PM_EVENT_FREEZE:
302 case PM_EVENT_QUIESCE:
303 return ops->freeze_late;
304 case PM_EVENT_HIBERNATE:
305 return ops->poweroff_late;
307 case PM_EVENT_RECOVER:
308 return ops->thaw_early;
309 case PM_EVENT_RESTORE:
310 return ops->restore_early;
311 #endif /* CONFIG_HIBERNATE_CALLBACKS */
318 * pm_noirq_op - Return the PM operation appropriate for given PM event.
319 * @ops: PM operations to choose from.
320 * @state: PM transition of the system being carried out.
322 * The driver of @dev will not receive interrupts while this function is being
325 static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
327 switch (state.event) {
328 #ifdef CONFIG_SUSPEND
329 case PM_EVENT_SUSPEND:
330 return ops->suspend_noirq;
331 case PM_EVENT_RESUME:
332 return ops->resume_noirq;
333 #endif /* CONFIG_SUSPEND */
334 #ifdef CONFIG_HIBERNATE_CALLBACKS
335 case PM_EVENT_FREEZE:
336 case PM_EVENT_QUIESCE:
337 return ops->freeze_noirq;
338 case PM_EVENT_HIBERNATE:
339 return ops->poweroff_noirq;
341 case PM_EVENT_RECOVER:
342 return ops->thaw_noirq;
343 case PM_EVENT_RESTORE:
344 return ops->restore_noirq;
345 #endif /* CONFIG_HIBERNATE_CALLBACKS */
351 static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
353 dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
354 ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
355 ", may wakeup" : "");
358 static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
361 printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
362 dev_name(dev), pm_verb(state.event), info, error);
365 static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info)
371 calltime = ktime_get();
372 usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
373 do_div(usecs64, NSEC_PER_USEC);
377 pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n",
378 info ?: "", info ? " " : "", pm_verb(state.event),
379 usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
382 static int dpm_run_callback(pm_callback_t cb, struct device *dev,
383 pm_message_t state, char *info)
391 calltime = initcall_debug_start(dev);
393 pm_dev_dbg(dev, state, info);
394 trace_device_pm_callback_start(dev, info, state.event);
396 trace_device_pm_callback_end(dev, error);
397 suspend_report_result(cb, error);
399 initcall_debug_report(dev, calltime, error, state, info);
404 #ifdef CONFIG_DPM_WATCHDOG
405 struct dpm_watchdog {
407 struct task_struct *tsk;
408 struct timer_list timer;
411 #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
412 struct dpm_watchdog wd
415 * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
416 * @data: Watchdog object address.
418 * Called when a driver has timed out suspending or resuming.
419 * There's not much we can do here to recover so panic() to
420 * capture a crash-dump in pstore.
422 static void dpm_watchdog_handler(unsigned long data)
424 struct dpm_watchdog *wd = (void *)data;
426 dev_emerg(wd->dev, "**** DPM device timeout ****\n");
427 show_stack(wd->tsk, NULL);
428 panic("%s %s: unrecoverable failure\n",
429 dev_driver_string(wd->dev), dev_name(wd->dev));
433 * dpm_watchdog_set - Enable pm watchdog for given device.
434 * @wd: Watchdog. Must be allocated on the stack.
435 * @dev: Device to handle.
437 static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
439 struct timer_list *timer = &wd->timer;
444 init_timer_on_stack(timer);
445 /* use same timeout value for both suspend and resume */
446 timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
447 timer->function = dpm_watchdog_handler;
448 timer->data = (unsigned long)wd;
453 * dpm_watchdog_clear - Disable suspend/resume watchdog.
454 * @wd: Watchdog to disable.
456 static void dpm_watchdog_clear(struct dpm_watchdog *wd)
458 struct timer_list *timer = &wd->timer;
460 del_timer_sync(timer);
461 destroy_timer_on_stack(timer);
464 #define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
465 #define dpm_watchdog_set(x, y)
466 #define dpm_watchdog_clear(x)
469 /*------------------------- Resume routines -------------------------*/
472 * device_resume_noirq - Execute an "early resume" callback for given device.
473 * @dev: Device to handle.
474 * @state: PM transition of the system being carried out.
475 * @async: If true, the device is being resumed asynchronously.
477 * The driver of @dev will not receive interrupts while this function is being
480 static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
482 pm_callback_t callback = NULL;
489 if (dev->power.syscore || dev->power.direct_complete)
492 if (!dev->power.is_noirq_suspended)
495 dpm_wait(dev->parent, async);
497 if (dev->pm_domain) {
498 info = "noirq power domain ";
499 callback = pm_noirq_op(&dev->pm_domain->ops, state);
500 } else if (dev->type && dev->type->pm) {
501 info = "noirq type ";
502 callback = pm_noirq_op(dev->type->pm, state);
503 } else if (dev->class && dev->class->pm) {
504 info = "noirq class ";
505 callback = pm_noirq_op(dev->class->pm, state);
506 } else if (dev->bus && dev->bus->pm) {
508 callback = pm_noirq_op(dev->bus->pm, state);
511 if (!callback && dev->driver && dev->driver->pm) {
512 info = "noirq driver ";
513 callback = pm_noirq_op(dev->driver->pm, state);
516 error = dpm_run_callback(callback, dev, state, info);
517 dev->power.is_noirq_suspended = false;
520 complete_all(&dev->power.completion);
525 static bool is_async(struct device *dev)
527 return dev->power.async_suspend && pm_async_enabled
528 && !pm_trace_is_enabled();
531 static void async_resume_noirq(void *data, async_cookie_t cookie)
533 struct device *dev = (struct device *)data;
536 error = device_resume_noirq(dev, pm_transition, true);
538 pm_dev_err(dev, pm_transition, " async", error);
544 * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
545 * @state: PM transition of the system being carried out.
547 * Call the "noirq" resume handlers for all devices in dpm_noirq_list and
548 * enable device drivers to receive interrupts.
550 void dpm_resume_noirq(pm_message_t state)
553 ktime_t starttime = ktime_get();
555 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
556 mutex_lock(&dpm_list_mtx);
557 pm_transition = state;
560 * Advanced the async threads upfront,
561 * in case the starting of async threads is
562 * delayed by non-async resuming devices.
564 list_for_each_entry(dev, &dpm_noirq_list, power.entry) {
565 reinit_completion(&dev->power.completion);
568 async_schedule(async_resume_noirq, dev);
572 while (!list_empty(&dpm_noirq_list)) {
573 dev = to_device(dpm_noirq_list.next);
575 list_move_tail(&dev->power.entry, &dpm_late_early_list);
576 mutex_unlock(&dpm_list_mtx);
578 if (!is_async(dev)) {
581 error = device_resume_noirq(dev, state, false);
583 suspend_stats.failed_resume_noirq++;
584 dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
585 dpm_save_failed_dev(dev_name(dev));
586 pm_dev_err(dev, state, " noirq", error);
590 mutex_lock(&dpm_list_mtx);
593 mutex_unlock(&dpm_list_mtx);
594 async_synchronize_full();
595 dpm_show_time(starttime, state, "noirq");
596 resume_device_irqs();
597 device_wakeup_disarm_wake_irqs();
599 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
603 * device_resume_early - Execute an "early resume" callback for given device.
604 * @dev: Device to handle.
605 * @state: PM transition of the system being carried out.
606 * @async: If true, the device is being resumed asynchronously.
608 * Runtime PM is disabled for @dev while this function is being executed.
610 static int device_resume_early(struct device *dev, pm_message_t state, bool async)
612 pm_callback_t callback = NULL;
619 if (dev->power.syscore || dev->power.direct_complete)
622 if (!dev->power.is_late_suspended)
625 dpm_wait(dev->parent, async);
627 if (dev->pm_domain) {
628 info = "early power domain ";
629 callback = pm_late_early_op(&dev->pm_domain->ops, state);
630 } else if (dev->type && dev->type->pm) {
631 info = "early type ";
632 callback = pm_late_early_op(dev->type->pm, state);
633 } else if (dev->class && dev->class->pm) {
634 info = "early class ";
635 callback = pm_late_early_op(dev->class->pm, state);
636 } else if (dev->bus && dev->bus->pm) {
638 callback = pm_late_early_op(dev->bus->pm, state);
641 if (!callback && dev->driver && dev->driver->pm) {
642 info = "early driver ";
643 callback = pm_late_early_op(dev->driver->pm, state);
646 error = dpm_run_callback(callback, dev, state, info);
647 dev->power.is_late_suspended = false;
652 pm_runtime_enable(dev);
653 complete_all(&dev->power.completion);
657 static void async_resume_early(void *data, async_cookie_t cookie)
659 struct device *dev = (struct device *)data;
662 error = device_resume_early(dev, pm_transition, true);
664 pm_dev_err(dev, pm_transition, " async", error);
670 * dpm_resume_early - Execute "early resume" callbacks for all devices.
671 * @state: PM transition of the system being carried out.
673 void dpm_resume_early(pm_message_t state)
676 ktime_t starttime = ktime_get();
678 trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
679 mutex_lock(&dpm_list_mtx);
680 pm_transition = state;
683 * Advanced the async threads upfront,
684 * in case the starting of async threads is
685 * delayed by non-async resuming devices.
687 list_for_each_entry(dev, &dpm_late_early_list, power.entry) {
688 reinit_completion(&dev->power.completion);
691 async_schedule(async_resume_early, dev);
695 while (!list_empty(&dpm_late_early_list)) {
696 dev = to_device(dpm_late_early_list.next);
698 list_move_tail(&dev->power.entry, &dpm_suspended_list);
699 mutex_unlock(&dpm_list_mtx);
701 if (!is_async(dev)) {
704 error = device_resume_early(dev, state, false);
706 suspend_stats.failed_resume_early++;
707 dpm_save_failed_step(SUSPEND_RESUME_EARLY);
708 dpm_save_failed_dev(dev_name(dev));
709 pm_dev_err(dev, state, " early", error);
712 mutex_lock(&dpm_list_mtx);
715 mutex_unlock(&dpm_list_mtx);
716 async_synchronize_full();
717 dpm_show_time(starttime, state, "early");
718 trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
722 * dpm_resume_start - Execute "noirq" and "early" device callbacks.
723 * @state: PM transition of the system being carried out.
725 void dpm_resume_start(pm_message_t state)
727 dpm_resume_noirq(state);
728 dpm_resume_early(state);
730 EXPORT_SYMBOL_GPL(dpm_resume_start);
733 * device_resume - Execute "resume" callbacks for given device.
734 * @dev: Device to handle.
735 * @state: PM transition of the system being carried out.
736 * @async: If true, the device is being resumed asynchronously.
738 static int device_resume(struct device *dev, pm_message_t state, bool async)
740 pm_callback_t callback = NULL;
743 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
748 if (dev->power.syscore)
751 if (dev->power.direct_complete) {
752 /* Match the pm_runtime_disable() in __device_suspend(). */
753 pm_runtime_enable(dev);
757 dpm_wait(dev->parent, async);
758 dpm_watchdog_set(&wd, dev);
762 * This is a fib. But we'll allow new children to be added below
763 * a resumed device, even if the device hasn't been completed yet.
765 dev->power.is_prepared = false;
767 if (!dev->power.is_suspended)
770 if (dev->pm_domain) {
771 info = "power domain ";
772 callback = pm_op(&dev->pm_domain->ops, state);
776 if (dev->type && dev->type->pm) {
778 callback = pm_op(dev->type->pm, state);
783 if (dev->class->pm) {
785 callback = pm_op(dev->class->pm, state);
787 } else if (dev->class->resume) {
788 info = "legacy class ";
789 callback = dev->class->resume;
797 callback = pm_op(dev->bus->pm, state);
798 } else if (dev->bus->resume) {
799 info = "legacy bus ";
800 callback = dev->bus->resume;
806 if (!callback && dev->driver && dev->driver->pm) {
808 callback = pm_op(dev->driver->pm, state);
812 error = dpm_run_callback(callback, dev, state, info);
813 dev->power.is_suspended = false;
817 dpm_watchdog_clear(&wd);
820 complete_all(&dev->power.completion);
827 static void async_resume(void *data, async_cookie_t cookie)
829 struct device *dev = (struct device *)data;
832 error = device_resume(dev, pm_transition, true);
834 pm_dev_err(dev, pm_transition, " async", error);
839 * dpm_drv_timeout - Driver suspend / resume watchdog handler
840 * @data: struct device which timed out
842 * Called when a driver has timed out suspending or resuming.
843 * There's not much we can do here to recover so
844 * BUG() out for a crash-dump
847 static void dpm_drv_timeout(unsigned long data)
849 struct dpm_drv_wd_data *wd_data = (void *)data;
850 struct device *dev = wd_data->dev;
851 struct task_struct *tsk = wd_data->tsk;
853 printk(KERN_EMERG "**** DPM device timeout: %s (%s)\n", dev_name(dev),
854 (dev->driver ? dev->driver->name : "no driver"));
856 printk(KERN_EMERG "dpm suspend stack:\n");
857 show_stack(tsk, NULL);
863 * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
864 * @state: PM transition of the system being carried out.
866 * Execute the appropriate "resume" callback for all devices whose status
867 * indicates that they are suspended.
869 void dpm_resume(pm_message_t state)
872 ktime_t starttime = ktime_get();
874 trace_suspend_resume(TPS("dpm_resume"), state.event, true);
877 mutex_lock(&dpm_list_mtx);
878 pm_transition = state;
881 list_for_each_entry(dev, &dpm_suspended_list, power.entry) {
882 reinit_completion(&dev->power.completion);
885 async_schedule(async_resume, dev);
889 while (!list_empty(&dpm_suspended_list)) {
890 dev = to_device(dpm_suspended_list.next);
892 if (!is_async(dev)) {
895 mutex_unlock(&dpm_list_mtx);
897 error = device_resume(dev, state, false);
899 suspend_stats.failed_resume++;
900 dpm_save_failed_step(SUSPEND_RESUME);
901 dpm_save_failed_dev(dev_name(dev));
902 pm_dev_err(dev, state, "", error);
905 mutex_lock(&dpm_list_mtx);
907 if (!list_empty(&dev->power.entry))
908 list_move_tail(&dev->power.entry, &dpm_prepared_list);
911 mutex_unlock(&dpm_list_mtx);
912 async_synchronize_full();
913 dpm_show_time(starttime, state, NULL);
916 trace_suspend_resume(TPS("dpm_resume"), state.event, false);
920 * device_complete - Complete a PM transition for given device.
921 * @dev: Device to handle.
922 * @state: PM transition of the system being carried out.
924 static void device_complete(struct device *dev, pm_message_t state)
926 void (*callback)(struct device *) = NULL;
929 if (dev->power.syscore)
934 if (dev->pm_domain) {
935 info = "completing power domain ";
936 callback = dev->pm_domain->ops.complete;
937 } else if (dev->type && dev->type->pm) {
938 info = "completing type ";
939 callback = dev->type->pm->complete;
940 } else if (dev->class && dev->class->pm) {
941 info = "completing class ";
942 callback = dev->class->pm->complete;
943 } else if (dev->bus && dev->bus->pm) {
944 info = "completing bus ";
945 callback = dev->bus->pm->complete;
948 if (!callback && dev->driver && dev->driver->pm) {
949 info = "completing driver ";
950 callback = dev->driver->pm->complete;
954 pm_dev_dbg(dev, state, info);
964 * dpm_complete - Complete a PM transition for all non-sysdev devices.
965 * @state: PM transition of the system being carried out.
967 * Execute the ->complete() callbacks for all devices whose PM status is not
968 * DPM_ON (this allows new devices to be registered).
970 void dpm_complete(pm_message_t state)
972 struct list_head list;
974 trace_suspend_resume(TPS("dpm_complete"), state.event, true);
977 INIT_LIST_HEAD(&list);
978 mutex_lock(&dpm_list_mtx);
979 while (!list_empty(&dpm_prepared_list)) {
980 struct device *dev = to_device(dpm_prepared_list.prev);
983 dev->power.is_prepared = false;
984 list_move(&dev->power.entry, &list);
985 mutex_unlock(&dpm_list_mtx);
987 trace_device_pm_callback_start(dev, "", state.event);
988 device_complete(dev, state);
989 trace_device_pm_callback_end(dev, 0);
991 mutex_lock(&dpm_list_mtx);
994 list_splice(&list, &dpm_list);
995 mutex_unlock(&dpm_list_mtx);
996 trace_suspend_resume(TPS("dpm_complete"), state.event, false);
1000 * dpm_resume_end - Execute "resume" callbacks and complete system transition.
1001 * @state: PM transition of the system being carried out.
1003 * Execute "resume" callbacks for all devices and complete the PM transition of
1006 void dpm_resume_end(pm_message_t state)
1009 dpm_complete(state);
1011 EXPORT_SYMBOL_GPL(dpm_resume_end);
1014 /*------------------------- Suspend routines -------------------------*/
1017 * resume_event - Return a "resume" message for given "suspend" sleep state.
1018 * @sleep_state: PM message representing a sleep state.
1020 * Return a PM message representing the resume event corresponding to given
1023 static pm_message_t resume_event(pm_message_t sleep_state)
1025 switch (sleep_state.event) {
1026 case PM_EVENT_SUSPEND:
1028 case PM_EVENT_FREEZE:
1029 case PM_EVENT_QUIESCE:
1030 return PMSG_RECOVER;
1031 case PM_EVENT_HIBERNATE:
1032 return PMSG_RESTORE;
1038 * device_suspend_noirq - Execute a "late suspend" callback for given device.
1039 * @dev: Device to handle.
1040 * @state: PM transition of the system being carried out.
1041 * @async: If true, the device is being suspended asynchronously.
1043 * The driver of @dev will not receive interrupts while this function is being
1046 static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
1048 pm_callback_t callback = NULL;
1058 if (pm_wakeup_pending()) {
1059 async_error = -EBUSY;
1063 if (dev->power.syscore || dev->power.direct_complete)
1066 dpm_wait_for_children(dev, async);
1068 if (dev->pm_domain) {
1069 info = "noirq power domain ";
1070 callback = pm_noirq_op(&dev->pm_domain->ops, state);
1071 } else if (dev->type && dev->type->pm) {
1072 info = "noirq type ";
1073 callback = pm_noirq_op(dev->type->pm, state);
1074 } else if (dev->class && dev->class->pm) {
1075 info = "noirq class ";
1076 callback = pm_noirq_op(dev->class->pm, state);
1077 } else if (dev->bus && dev->bus->pm) {
1078 info = "noirq bus ";
1079 callback = pm_noirq_op(dev->bus->pm, state);
1082 if (!callback && dev->driver && dev->driver->pm) {
1083 info = "noirq driver ";
1084 callback = pm_noirq_op(dev->driver->pm, state);
1087 error = dpm_run_callback(callback, dev, state, info);
1089 dev->power.is_noirq_suspended = true;
1091 async_error = error;
1094 complete_all(&dev->power.completion);
1095 TRACE_SUSPEND(error);
1099 static void async_suspend_noirq(void *data, async_cookie_t cookie)
1101 struct device *dev = (struct device *)data;
1104 error = __device_suspend_noirq(dev, pm_transition, true);
1106 dpm_save_failed_dev(dev_name(dev));
1107 pm_dev_err(dev, pm_transition, " async", error);
1113 static int device_suspend_noirq(struct device *dev)
1115 reinit_completion(&dev->power.completion);
1117 if (is_async(dev)) {
1119 async_schedule(async_suspend_noirq, dev);
1122 return __device_suspend_noirq(dev, pm_transition, false);
1126 * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
1127 * @state: PM transition of the system being carried out.
1129 * Prevent device drivers from receiving interrupts and call the "noirq" suspend
1130 * handlers for all non-sysdev devices.
1132 int dpm_suspend_noirq(pm_message_t state)
1134 ktime_t starttime = ktime_get();
1137 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
1139 device_wakeup_arm_wake_irqs();
1140 suspend_device_irqs();
1141 mutex_lock(&dpm_list_mtx);
1142 pm_transition = state;
1145 while (!list_empty(&dpm_late_early_list)) {
1146 struct device *dev = to_device(dpm_late_early_list.prev);
1149 mutex_unlock(&dpm_list_mtx);
1151 error = device_suspend_noirq(dev);
1153 mutex_lock(&dpm_list_mtx);
1155 pm_dev_err(dev, state, " noirq", error);
1156 dpm_save_failed_dev(dev_name(dev));
1160 if (!list_empty(&dev->power.entry))
1161 list_move(&dev->power.entry, &dpm_noirq_list);
1167 mutex_unlock(&dpm_list_mtx);
1168 async_synchronize_full();
1170 error = async_error;
1173 suspend_stats.failed_suspend_noirq++;
1174 dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
1175 dpm_resume_noirq(resume_event(state));
1177 dpm_show_time(starttime, state, "noirq");
1179 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
1184 * device_suspend_late - Execute a "late suspend" callback for given device.
1185 * @dev: Device to handle.
1186 * @state: PM transition of the system being carried out.
1187 * @async: If true, the device is being suspended asynchronously.
1189 * Runtime PM is disabled for @dev while this function is being executed.
1191 static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
1193 pm_callback_t callback = NULL;
1200 __pm_runtime_disable(dev, false);
1205 if (pm_wakeup_pending()) {
1206 async_error = -EBUSY;
1210 if (dev->power.syscore || dev->power.direct_complete)
1213 dpm_wait_for_children(dev, async);
1215 if (dev->pm_domain) {
1216 info = "late power domain ";
1217 callback = pm_late_early_op(&dev->pm_domain->ops, state);
1218 } else if (dev->type && dev->type->pm) {
1219 info = "late type ";
1220 callback = pm_late_early_op(dev->type->pm, state);
1221 } else if (dev->class && dev->class->pm) {
1222 info = "late class ";
1223 callback = pm_late_early_op(dev->class->pm, state);
1224 } else if (dev->bus && dev->bus->pm) {
1226 callback = pm_late_early_op(dev->bus->pm, state);
1229 if (!callback && dev->driver && dev->driver->pm) {
1230 info = "late driver ";
1231 callback = pm_late_early_op(dev->driver->pm, state);
1234 error = dpm_run_callback(callback, dev, state, info);
1236 dev->power.is_late_suspended = true;
1238 async_error = error;
1241 TRACE_SUSPEND(error);
1242 complete_all(&dev->power.completion);
1246 static void async_suspend_late(void *data, async_cookie_t cookie)
1248 struct device *dev = (struct device *)data;
1251 error = __device_suspend_late(dev, pm_transition, true);
1253 dpm_save_failed_dev(dev_name(dev));
1254 pm_dev_err(dev, pm_transition, " async", error);
1259 static int device_suspend_late(struct device *dev)
1261 reinit_completion(&dev->power.completion);
1263 if (is_async(dev)) {
1265 async_schedule(async_suspend_late, dev);
1269 return __device_suspend_late(dev, pm_transition, false);
1273 * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
1274 * @state: PM transition of the system being carried out.
1276 int dpm_suspend_late(pm_message_t state)
1278 ktime_t starttime = ktime_get();
1281 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
1282 mutex_lock(&dpm_list_mtx);
1283 pm_transition = state;
1286 while (!list_empty(&dpm_suspended_list)) {
1287 struct device *dev = to_device(dpm_suspended_list.prev);
1290 mutex_unlock(&dpm_list_mtx);
1292 error = device_suspend_late(dev);
1294 mutex_lock(&dpm_list_mtx);
1296 pm_dev_err(dev, state, " late", error);
1297 dpm_save_failed_dev(dev_name(dev));
1301 if (!list_empty(&dev->power.entry))
1302 list_move(&dev->power.entry, &dpm_late_early_list);
1308 mutex_unlock(&dpm_list_mtx);
1309 async_synchronize_full();
1311 error = async_error;
1313 suspend_stats.failed_suspend_late++;
1314 dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
1315 dpm_resume_early(resume_event(state));
1317 dpm_show_time(starttime, state, "late");
1319 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
1324 * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
1325 * @state: PM transition of the system being carried out.
1327 int dpm_suspend_end(pm_message_t state)
1329 int error = dpm_suspend_late(state);
1333 error = dpm_suspend_noirq(state);
1335 dpm_resume_early(resume_event(state));
1341 EXPORT_SYMBOL_GPL(dpm_suspend_end);
1344 * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
1345 * @dev: Device to suspend.
1346 * @state: PM transition of the system being carried out.
1347 * @cb: Suspend callback to execute.
1348 * @info: string description of caller.
1350 static int legacy_suspend(struct device *dev, pm_message_t state,
1351 int (*cb)(struct device *dev, pm_message_t state),
1357 calltime = initcall_debug_start(dev);
1359 trace_device_pm_callback_start(dev, info, state.event);
1360 error = cb(dev, state);
1361 trace_device_pm_callback_end(dev, error);
1362 suspend_report_result(cb, error);
1364 initcall_debug_report(dev, calltime, error, state, info);
1370 * device_suspend - Execute "suspend" callbacks for given device.
1371 * @dev: Device to handle.
1372 * @state: PM transition of the system being carried out.
1373 * @async: If true, the device is being suspended asynchronously.
1375 static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1377 pm_callback_t callback = NULL;
1380 struct timer_list timer;
1381 struct dpm_drv_wd_data data;
1382 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
1387 dpm_wait_for_children(dev, async);
1393 * If a device configured to wake up the system from sleep states
1394 * has been suspended at run time and there's a resume request pending
1395 * for it, this is equivalent to the device signaling wakeup, so the
1396 * system suspend operation should be aborted.
1398 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
1399 pm_wakeup_event(dev, 0);
1401 if (pm_wakeup_pending()) {
1402 async_error = -EBUSY;
1406 if (dev->power.syscore)
1410 data.tsk = get_current();
1411 init_timer_on_stack(&timer);
1412 timer.expires = jiffies + HZ * 12;
1413 timer.function = dpm_drv_timeout;
1414 timer.data = (unsigned long)&data;
1417 if (dev->power.direct_complete) {
1418 if (pm_runtime_status_suspended(dev)) {
1419 pm_runtime_disable(dev);
1420 if (pm_runtime_status_suspended(dev))
1423 pm_runtime_enable(dev);
1425 dev->power.direct_complete = false;
1428 dpm_watchdog_set(&wd, dev);
1431 if (dev->pm_domain) {
1432 info = "power domain ";
1433 callback = pm_op(&dev->pm_domain->ops, state);
1437 if (dev->type && dev->type->pm) {
1439 callback = pm_op(dev->type->pm, state);
1444 if (dev->class->pm) {
1446 callback = pm_op(dev->class->pm, state);
1448 } else if (dev->class->suspend) {
1449 pm_dev_dbg(dev, state, "legacy class ");
1450 error = legacy_suspend(dev, state, dev->class->suspend,
1459 callback = pm_op(dev->bus->pm, state);
1460 } else if (dev->bus->suspend) {
1461 pm_dev_dbg(dev, state, "legacy bus ");
1462 error = legacy_suspend(dev, state, dev->bus->suspend,
1469 if (!callback && dev->driver && dev->driver->pm) {
1471 callback = pm_op(dev->driver->pm, state);
1474 error = dpm_run_callback(callback, dev, state, info);
1478 struct device *parent = dev->parent;
1480 dev->power.is_suspended = true;
1482 spin_lock_irq(&parent->power.lock);
1484 dev->parent->power.direct_complete = false;
1485 if (dev->power.wakeup_path
1486 && !dev->parent->power.ignore_children)
1487 dev->parent->power.wakeup_path = true;
1489 spin_unlock_irq(&parent->power.lock);
1494 dpm_watchdog_clear(&wd);
1496 del_timer_sync(&timer);
1497 destroy_timer_on_stack(&timer);
1500 complete_all(&dev->power.completion);
1502 async_error = error;
1504 TRACE_SUSPEND(error);
1508 static void async_suspend(void *data, async_cookie_t cookie)
1510 struct device *dev = (struct device *)data;
1513 error = __device_suspend(dev, pm_transition, true);
1515 dpm_save_failed_dev(dev_name(dev));
1516 pm_dev_err(dev, pm_transition, " async", error);
1522 static int device_suspend(struct device *dev)
1524 reinit_completion(&dev->power.completion);
1526 if (is_async(dev)) {
1528 async_schedule(async_suspend, dev);
1532 return __device_suspend(dev, pm_transition, false);
1536 * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
1537 * @state: PM transition of the system being carried out.
1539 int dpm_suspend(pm_message_t state)
1541 ktime_t starttime = ktime_get();
1544 trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
1549 mutex_lock(&dpm_list_mtx);
1550 pm_transition = state;
1552 while (!list_empty(&dpm_prepared_list)) {
1553 struct device *dev = to_device(dpm_prepared_list.prev);
1556 mutex_unlock(&dpm_list_mtx);
1558 error = device_suspend(dev);
1560 mutex_lock(&dpm_list_mtx);
1562 pm_dev_err(dev, state, "", error);
1563 dpm_save_failed_dev(dev_name(dev));
1567 if (!list_empty(&dev->power.entry))
1568 list_move(&dev->power.entry, &dpm_suspended_list);
1573 mutex_unlock(&dpm_list_mtx);
1574 async_synchronize_full();
1576 error = async_error;
1578 suspend_stats.failed_suspend++;
1579 dpm_save_failed_step(SUSPEND_SUSPEND);
1581 dpm_show_time(starttime, state, NULL);
1582 trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
1587 * device_prepare - Prepare a device for system power transition.
1588 * @dev: Device to handle.
1589 * @state: PM transition of the system being carried out.
1591 * Execute the ->prepare() callback(s) for given device. No new children of the
1592 * device may be registered after this function has returned.
1594 static int device_prepare(struct device *dev, pm_message_t state)
1596 int (*callback)(struct device *) = NULL;
1600 if (dev->power.syscore)
1604 * If a device's parent goes into runtime suspend at the wrong time,
1605 * it won't be possible to resume the device. To prevent this we
1606 * block runtime suspend here, during the prepare phase, and allow
1607 * it again during the complete phase.
1609 pm_runtime_get_noresume(dev);
1613 dev->power.wakeup_path = device_may_wakeup(dev);
1615 if (dev->pm_domain) {
1616 info = "preparing power domain ";
1617 callback = dev->pm_domain->ops.prepare;
1618 } else if (dev->type && dev->type->pm) {
1619 info = "preparing type ";
1620 callback = dev->type->pm->prepare;
1621 } else if (dev->class && dev->class->pm) {
1622 info = "preparing class ";
1623 callback = dev->class->pm->prepare;
1624 } else if (dev->bus && dev->bus->pm) {
1625 info = "preparing bus ";
1626 callback = dev->bus->pm->prepare;
1629 if (!callback && dev->driver && dev->driver->pm) {
1630 info = "preparing driver ";
1631 callback = dev->driver->pm->prepare;
1635 ret = callback(dev);
1640 suspend_report_result(callback, ret);
1641 pm_runtime_put(dev);
1645 * A positive return value from ->prepare() means "this device appears
1646 * to be runtime-suspended and its state is fine, so if it really is
1647 * runtime-suspended, you can leave it in that state provided that you
1648 * will do the same thing with all of its descendants". This only
1649 * applies to suspend transitions, however.
1651 spin_lock_irq(&dev->power.lock);
1652 dev->power.direct_complete = ret > 0 && state.event == PM_EVENT_SUSPEND;
1653 spin_unlock_irq(&dev->power.lock);
1658 * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1659 * @state: PM transition of the system being carried out.
1661 * Execute the ->prepare() callback(s) for all devices.
1663 int dpm_prepare(pm_message_t state)
1667 trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
1670 mutex_lock(&dpm_list_mtx);
1671 while (!list_empty(&dpm_list)) {
1672 struct device *dev = to_device(dpm_list.next);
1675 mutex_unlock(&dpm_list_mtx);
1677 trace_device_pm_callback_start(dev, "", state.event);
1678 error = device_prepare(dev, state);
1679 trace_device_pm_callback_end(dev, error);
1681 mutex_lock(&dpm_list_mtx);
1683 if (error == -EAGAIN) {
1688 printk(KERN_INFO "PM: Device %s not prepared "
1689 "for power transition: code %d\n",
1690 dev_name(dev), error);
1694 dev->power.is_prepared = true;
1695 if (!list_empty(&dev->power.entry))
1696 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1699 mutex_unlock(&dpm_list_mtx);
1700 trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
1705 * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1706 * @state: PM transition of the system being carried out.
1708 * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1709 * callbacks for them.
1711 int dpm_suspend_start(pm_message_t state)
1715 error = dpm_prepare(state);
1717 suspend_stats.failed_prepare++;
1718 dpm_save_failed_step(SUSPEND_PREPARE);
1720 error = dpm_suspend(state);
1723 EXPORT_SYMBOL_GPL(dpm_suspend_start);
1725 void __suspend_report_result(const char *function, void *fn, int ret)
1728 printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
1730 EXPORT_SYMBOL_GPL(__suspend_report_result);
1733 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1734 * @dev: Device to wait for.
1735 * @subordinate: Device that needs to wait for @dev.
1737 int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
1739 dpm_wait(dev, subordinate->power.async_suspend);
1742 EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
1745 * dpm_for_each_dev - device iterator.
1746 * @data: data for the callback.
1747 * @fn: function to be called for each device.
1749 * Iterate over devices in dpm_list, and call @fn for each device,
1752 void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
1760 list_for_each_entry(dev, &dpm_list, power.entry)
1764 EXPORT_SYMBOL_GPL(dpm_for_each_dev);