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- /*
- * drivers/base/power/main.c - Where the driver meets power management.
- *
- * Copyright (c) 2003 Patrick Mochel
- * Copyright (c) 2003 Open Source Development Lab
- *
- * This file is released under the GPLv2
- *
- *
- * The driver model core calls device_pm_add() when a device is registered.
- * This will initialize the embedded device_pm_info object in the device
- * and add it to the list of power-controlled devices. sysfs entries for
- * controlling device power management will also be added.
- *
- * A separate list is used for keeping track of power info, because the power
- * domain dependencies may differ from the ancestral dependencies that the
- * subsystem list maintains.
- */
- #include <linux/device.h>
- #include <linux/kallsyms.h>
- #include <linux/export.h>
- #include <linux/mutex.h>
- #include <linux/pm.h>
- #include <linux/pm_runtime.h>
- #include <linux/pm-trace.h>
- #include <linux/pm_wakeirq.h>
- #include <linux/interrupt.h>
- #include <linux/sched.h>
- #include <linux/async.h>
- #include <linux/suspend.h>
- #include <trace/events/power.h>
- #include <linux/cpufreq.h>
- #include <linux/cpuidle.h>
- #include <linux/timer.h>
- #include "../base.h"
- #include "power.h"
- typedef int (*pm_callback_t)(struct device *);
- /*
- * The entries in the dpm_list list are in a depth first order, simply
- * because children are guaranteed to be discovered after parents, and
- * are inserted at the back of the list on discovery.
- *
- * Since device_pm_add() may be called with a device lock held,
- * we must never try to acquire a device lock while holding
- * dpm_list_mutex.
- */
- LIST_HEAD(dpm_list);
- static LIST_HEAD(dpm_prepared_list);
- static LIST_HEAD(dpm_suspended_list);
- static LIST_HEAD(dpm_late_early_list);
- static LIST_HEAD(dpm_noirq_list);
- struct suspend_stats suspend_stats;
- static DEFINE_MUTEX(dpm_list_mtx);
- static pm_message_t pm_transition;
- static int async_error;
- static char *pm_verb(int event)
- {
- switch (event) {
- case PM_EVENT_SUSPEND:
- return "suspend";
- case PM_EVENT_RESUME:
- return "resume";
- case PM_EVENT_FREEZE:
- return "freeze";
- case PM_EVENT_QUIESCE:
- return "quiesce";
- case PM_EVENT_HIBERNATE:
- return "hibernate";
- case PM_EVENT_THAW:
- return "thaw";
- case PM_EVENT_RESTORE:
- return "restore";
- case PM_EVENT_RECOVER:
- return "recover";
- default:
- return "(unknown PM event)";
- }
- }
- /**
- * device_pm_sleep_init - Initialize system suspend-related device fields.
- * @dev: Device object being initialized.
- */
- void device_pm_sleep_init(struct device *dev)
- {
- dev->power.is_prepared = false;
- dev->power.is_suspended = false;
- dev->power.is_noirq_suspended = false;
- dev->power.is_late_suspended = false;
- init_completion(&dev->power.completion);
- complete_all(&dev->power.completion);
- dev->power.wakeup = NULL;
- INIT_LIST_HEAD(&dev->power.entry);
- }
- /**
- * device_pm_lock - Lock the list of active devices used by the PM core.
- */
- void device_pm_lock(void)
- {
- mutex_lock(&dpm_list_mtx);
- }
- /**
- * device_pm_unlock - Unlock the list of active devices used by the PM core.
- */
- void device_pm_unlock(void)
- {
- mutex_unlock(&dpm_list_mtx);
- }
- /**
- * device_pm_add - Add a device to the PM core's list of active devices.
- * @dev: Device to add to the list.
- */
- void device_pm_add(struct device *dev)
- {
- pr_debug("PM: Adding info for %s:%s\n",
- dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
- mutex_lock(&dpm_list_mtx);
- if (dev->parent && dev->parent->power.is_prepared)
- dev_warn(dev, "parent %s should not be sleeping\n",
- dev_name(dev->parent));
- list_add_tail(&dev->power.entry, &dpm_list);
- mutex_unlock(&dpm_list_mtx);
- }
- /**
- * device_pm_remove - Remove a device from the PM core's list of active devices.
- * @dev: Device to be removed from the list.
- */
- void device_pm_remove(struct device *dev)
- {
- pr_debug("PM: Removing info for %s:%s\n",
- dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
- complete_all(&dev->power.completion);
- mutex_lock(&dpm_list_mtx);
- list_del_init(&dev->power.entry);
- mutex_unlock(&dpm_list_mtx);
- device_wakeup_disable(dev);
- pm_runtime_remove(dev);
- }
- /**
- * device_pm_move_before - Move device in the PM core's list of active devices.
- * @deva: Device to move in dpm_list.
- * @devb: Device @deva should come before.
- */
- void device_pm_move_before(struct device *deva, struct device *devb)
- {
- pr_debug("PM: Moving %s:%s before %s:%s\n",
- deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
- devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
- /* Delete deva from dpm_list and reinsert before devb. */
- list_move_tail(&deva->power.entry, &devb->power.entry);
- }
- /**
- * device_pm_move_after - Move device in the PM core's list of active devices.
- * @deva: Device to move in dpm_list.
- * @devb: Device @deva should come after.
- */
- void device_pm_move_after(struct device *deva, struct device *devb)
- {
- pr_debug("PM: Moving %s:%s after %s:%s\n",
- deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
- devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
- /* Delete deva from dpm_list and reinsert after devb. */
- list_move(&deva->power.entry, &devb->power.entry);
- }
- /**
- * device_pm_move_last - Move device to end of the PM core's list of devices.
- * @dev: Device to move in dpm_list.
- */
- void device_pm_move_last(struct device *dev)
- {
- pr_debug("PM: Moving %s:%s to end of list\n",
- dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
- list_move_tail(&dev->power.entry, &dpm_list);
- }
- static ktime_t initcall_debug_start(struct device *dev)
- {
- ktime_t calltime = ktime_set(0, 0);
- if (pm_print_times_enabled) {
- pr_info("calling %s+ @ %i, parent: %s\n",
- dev_name(dev), task_pid_nr(current),
- dev->parent ? dev_name(dev->parent) : "none");
- calltime = ktime_get();
- }
- return calltime;
- }
- static void initcall_debug_report(struct device *dev, ktime_t calltime,
- int error, pm_message_t state, char *info)
- {
- ktime_t rettime;
- s64 nsecs;
- rettime = ktime_get();
- nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime));
- if (pm_print_times_enabled) {
- pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev),
- error, (unsigned long long)nsecs >> 10);
- }
- }
- /**
- * dpm_wait - Wait for a PM operation to complete.
- * @dev: Device to wait for.
- * @async: If unset, wait only if the device's power.async_suspend flag is set.
- */
- static void dpm_wait(struct device *dev, bool async)
- {
- if (!dev)
- return;
- if (async || (pm_async_enabled && dev->power.async_suspend))
- wait_for_completion(&dev->power.completion);
- }
- static int dpm_wait_fn(struct device *dev, void *async_ptr)
- {
- dpm_wait(dev, *((bool *)async_ptr));
- return 0;
- }
- static void dpm_wait_for_children(struct device *dev, bool async)
- {
- device_for_each_child(dev, &async, dpm_wait_fn);
- }
- /**
- * pm_op - Return the PM operation appropriate for given PM event.
- * @ops: PM operations to choose from.
- * @state: PM transition of the system being carried out.
- */
- static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
- {
- switch (state.event) {
- #ifdef CONFIG_SUSPEND
- case PM_EVENT_SUSPEND:
- return ops->suspend;
- case PM_EVENT_RESUME:
- return ops->resume;
- #endif /* CONFIG_SUSPEND */
- #ifdef CONFIG_HIBERNATE_CALLBACKS
- case PM_EVENT_FREEZE:
- case PM_EVENT_QUIESCE:
- return ops->freeze;
- case PM_EVENT_HIBERNATE:
- return ops->poweroff;
- case PM_EVENT_THAW:
- case PM_EVENT_RECOVER:
- return ops->thaw;
- break;
- case PM_EVENT_RESTORE:
- return ops->restore;
- #endif /* CONFIG_HIBERNATE_CALLBACKS */
- }
- return NULL;
- }
- /**
- * pm_late_early_op - Return the PM operation appropriate for given PM event.
- * @ops: PM operations to choose from.
- * @state: PM transition of the system being carried out.
- *
- * Runtime PM is disabled for @dev while this function is being executed.
- */
- static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
- pm_message_t state)
- {
- switch (state.event) {
- #ifdef CONFIG_SUSPEND
- case PM_EVENT_SUSPEND:
- return ops->suspend_late;
- case PM_EVENT_RESUME:
- return ops->resume_early;
- #endif /* CONFIG_SUSPEND */
- #ifdef CONFIG_HIBERNATE_CALLBACKS
- case PM_EVENT_FREEZE:
- case PM_EVENT_QUIESCE:
- return ops->freeze_late;
- case PM_EVENT_HIBERNATE:
- return ops->poweroff_late;
- case PM_EVENT_THAW:
- case PM_EVENT_RECOVER:
- return ops->thaw_early;
- case PM_EVENT_RESTORE:
- return ops->restore_early;
- #endif /* CONFIG_HIBERNATE_CALLBACKS */
- }
- return NULL;
- }
- /**
- * pm_noirq_op - Return the PM operation appropriate for given PM event.
- * @ops: PM operations to choose from.
- * @state: PM transition of the system being carried out.
- *
- * The driver of @dev will not receive interrupts while this function is being
- * executed.
- */
- static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
- {
- switch (state.event) {
- #ifdef CONFIG_SUSPEND
- case PM_EVENT_SUSPEND:
- return ops->suspend_noirq;
- case PM_EVENT_RESUME:
- return ops->resume_noirq;
- #endif /* CONFIG_SUSPEND */
- #ifdef CONFIG_HIBERNATE_CALLBACKS
- case PM_EVENT_FREEZE:
- case PM_EVENT_QUIESCE:
- return ops->freeze_noirq;
- case PM_EVENT_HIBERNATE:
- return ops->poweroff_noirq;
- case PM_EVENT_THAW:
- case PM_EVENT_RECOVER:
- return ops->thaw_noirq;
- case PM_EVENT_RESTORE:
- return ops->restore_noirq;
- #endif /* CONFIG_HIBERNATE_CALLBACKS */
- }
- return NULL;
- }
- static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
- {
- dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
- ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
- ", may wakeup" : "");
- }
- static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
- int error)
- {
- printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
- dev_name(dev), pm_verb(state.event), info, error);
- }
- static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info)
- {
- ktime_t calltime;
- u64 usecs64;
- int usecs;
- calltime = ktime_get();
- usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
- do_div(usecs64, NSEC_PER_USEC);
- usecs = usecs64;
- if (usecs == 0)
- usecs = 1;
- pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n",
- info ?: "", info ? " " : "", pm_verb(state.event),
- usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
- }
- static int dpm_run_callback(pm_callback_t cb, struct device *dev,
- pm_message_t state, char *info)
- {
- ktime_t calltime;
- int error;
- if (!cb)
- return 0;
- calltime = initcall_debug_start(dev);
- pm_dev_dbg(dev, state, info);
- trace_device_pm_callback_start(dev, info, state.event);
- error = cb(dev);
- trace_device_pm_callback_end(dev, error);
- suspend_report_result(cb, error);
- initcall_debug_report(dev, calltime, error, state, info);
- return error;
- }
- #ifdef CONFIG_DPM_WATCHDOG
- struct dpm_watchdog {
- struct device *dev;
- struct task_struct *tsk;
- struct timer_list timer;
- };
- #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
- struct dpm_watchdog wd
- /**
- * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
- * @data: Watchdog object address.
- *
- * Called when a driver has timed out suspending or resuming.
- * There's not much we can do here to recover so panic() to
- * capture a crash-dump in pstore.
- */
- static void dpm_watchdog_handler(unsigned long data)
- {
- struct dpm_watchdog *wd = (void *)data;
- dev_emerg(wd->dev, "**** DPM device timeout ****\n");
- show_stack(wd->tsk, NULL);
- panic("%s %s: unrecoverable failure\n",
- dev_driver_string(wd->dev), dev_name(wd->dev));
- }
- /**
- * dpm_watchdog_set - Enable pm watchdog for given device.
- * @wd: Watchdog. Must be allocated on the stack.
- * @dev: Device to handle.
- */
- static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
- {
- struct timer_list *timer = &wd->timer;
- wd->dev = dev;
- wd->tsk = current;
- init_timer_on_stack(timer);
- /* use same timeout value for both suspend and resume */
- timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
- timer->function = dpm_watchdog_handler;
- timer->data = (unsigned long)wd;
- add_timer(timer);
- }
- /**
- * dpm_watchdog_clear - Disable suspend/resume watchdog.
- * @wd: Watchdog to disable.
- */
- static void dpm_watchdog_clear(struct dpm_watchdog *wd)
- {
- struct timer_list *timer = &wd->timer;
- del_timer_sync(timer);
- destroy_timer_on_stack(timer);
- }
- #else
- #define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
- #define dpm_watchdog_set(x, y)
- #define dpm_watchdog_clear(x)
- #endif
- /*------------------------- Resume routines -------------------------*/
- /**
- * device_resume_noirq - Execute an "early resume" callback for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being resumed asynchronously.
- *
- * The driver of @dev will not receive interrupts while this function is being
- * executed.
- */
- static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- TRACE_DEVICE(dev);
- TRACE_RESUME(0);
- if (dev->power.syscore || dev->power.direct_complete)
- goto Out;
- if (!dev->power.is_noirq_suspended)
- goto Out;
- dpm_wait(dev->parent, async);
- if (dev->pm_domain) {
- info = "noirq power domain ";
- callback = pm_noirq_op(&dev->pm_domain->ops, state);
- } else if (dev->type && dev->type->pm) {
- info = "noirq type ";
- callback = pm_noirq_op(dev->type->pm, state);
- } else if (dev->class && dev->class->pm) {
- info = "noirq class ";
- callback = pm_noirq_op(dev->class->pm, state);
- } else if (dev->bus && dev->bus->pm) {
- info = "noirq bus ";
- callback = pm_noirq_op(dev->bus->pm, state);
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "noirq driver ";
- callback = pm_noirq_op(dev->driver->pm, state);
- }
- error = dpm_run_callback(callback, dev, state, info);
- dev->power.is_noirq_suspended = false;
- Out:
- complete_all(&dev->power.completion);
- TRACE_RESUME(error);
- return error;
- }
- static bool is_async(struct device *dev)
- {
- return dev->power.async_suspend && pm_async_enabled
- && !pm_trace_is_enabled();
- }
- static void async_resume_noirq(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = device_resume_noirq(dev, pm_transition, true);
- if (error)
- pm_dev_err(dev, pm_transition, " async", error);
- put_device(dev);
- }
- /**
- * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
- * @state: PM transition of the system being carried out.
- *
- * Call the "noirq" resume handlers for all devices in dpm_noirq_list and
- * enable device drivers to receive interrupts.
- */
- void dpm_resume_noirq(pm_message_t state)
- {
- struct device *dev;
- ktime_t starttime = ktime_get();
- trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- /*
- * Advanced the async threads upfront,
- * in case the starting of async threads is
- * delayed by non-async resuming devices.
- */
- list_for_each_entry(dev, &dpm_noirq_list, power.entry) {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_resume_noirq, dev);
- }
- }
- while (!list_empty(&dpm_noirq_list)) {
- dev = to_device(dpm_noirq_list.next);
- get_device(dev);
- list_move_tail(&dev->power.entry, &dpm_late_early_list);
- mutex_unlock(&dpm_list_mtx);
- if (!is_async(dev)) {
- int error;
- error = device_resume_noirq(dev, state, false);
- if (error) {
- suspend_stats.failed_resume_noirq++;
- dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, state, " noirq", error);
- }
- }
- mutex_lock(&dpm_list_mtx);
- put_device(dev);
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- dpm_show_time(starttime, state, "noirq");
- resume_device_irqs();
- device_wakeup_disarm_wake_irqs();
- cpuidle_resume();
- trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
- }
- /**
- * device_resume_early - Execute an "early resume" callback for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being resumed asynchronously.
- *
- * Runtime PM is disabled for @dev while this function is being executed.
- */
- static int device_resume_early(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- TRACE_DEVICE(dev);
- TRACE_RESUME(0);
- if (dev->power.syscore || dev->power.direct_complete)
- goto Out;
- if (!dev->power.is_late_suspended)
- goto Out;
- dpm_wait(dev->parent, async);
- if (dev->pm_domain) {
- info = "early power domain ";
- callback = pm_late_early_op(&dev->pm_domain->ops, state);
- } else if (dev->type && dev->type->pm) {
- info = "early type ";
- callback = pm_late_early_op(dev->type->pm, state);
- } else if (dev->class && dev->class->pm) {
- info = "early class ";
- callback = pm_late_early_op(dev->class->pm, state);
- } else if (dev->bus && dev->bus->pm) {
- info = "early bus ";
- callback = pm_late_early_op(dev->bus->pm, state);
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "early driver ";
- callback = pm_late_early_op(dev->driver->pm, state);
- }
- error = dpm_run_callback(callback, dev, state, info);
- dev->power.is_late_suspended = false;
- Out:
- TRACE_RESUME(error);
- pm_runtime_enable(dev);
- complete_all(&dev->power.completion);
- return error;
- }
- static void async_resume_early(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = device_resume_early(dev, pm_transition, true);
- if (error)
- pm_dev_err(dev, pm_transition, " async", error);
- put_device(dev);
- }
- /**
- * dpm_resume_early - Execute "early resume" callbacks for all devices.
- * @state: PM transition of the system being carried out.
- */
- void dpm_resume_early(pm_message_t state)
- {
- struct device *dev;
- ktime_t starttime = ktime_get();
- trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- /*
- * Advanced the async threads upfront,
- * in case the starting of async threads is
- * delayed by non-async resuming devices.
- */
- list_for_each_entry(dev, &dpm_late_early_list, power.entry) {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_resume_early, dev);
- }
- }
- while (!list_empty(&dpm_late_early_list)) {
- dev = to_device(dpm_late_early_list.next);
- get_device(dev);
- list_move_tail(&dev->power.entry, &dpm_suspended_list);
- mutex_unlock(&dpm_list_mtx);
- if (!is_async(dev)) {
- int error;
- error = device_resume_early(dev, state, false);
- if (error) {
- suspend_stats.failed_resume_early++;
- dpm_save_failed_step(SUSPEND_RESUME_EARLY);
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, state, " early", error);
- }
- }
- mutex_lock(&dpm_list_mtx);
- put_device(dev);
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- dpm_show_time(starttime, state, "early");
- trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
- }
- /**
- * dpm_resume_start - Execute "noirq" and "early" device callbacks.
- * @state: PM transition of the system being carried out.
- */
- void dpm_resume_start(pm_message_t state)
- {
- dpm_resume_noirq(state);
- dpm_resume_early(state);
- }
- EXPORT_SYMBOL_GPL(dpm_resume_start);
- /**
- * device_resume - Execute "resume" callbacks for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being resumed asynchronously.
- */
- static int device_resume(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- DECLARE_DPM_WATCHDOG_ON_STACK(wd);
- TRACE_DEVICE(dev);
- TRACE_RESUME(0);
- if (dev->power.syscore)
- goto Complete;
- if (dev->power.direct_complete) {
- /* Match the pm_runtime_disable() in __device_suspend(). */
- pm_runtime_enable(dev);
- goto Complete;
- }
- dpm_wait(dev->parent, async);
- dpm_watchdog_set(&wd, dev);
- device_lock(dev);
- /*
- * This is a fib. But we'll allow new children to be added below
- * a resumed device, even if the device hasn't been completed yet.
- */
- dev->power.is_prepared = false;
- if (!dev->power.is_suspended)
- goto Unlock;
- if (dev->pm_domain) {
- info = "power domain ";
- callback = pm_op(&dev->pm_domain->ops, state);
- goto Driver;
- }
- if (dev->type && dev->type->pm) {
- info = "type ";
- callback = pm_op(dev->type->pm, state);
- goto Driver;
- }
- if (dev->class) {
- if (dev->class->pm) {
- info = "class ";
- callback = pm_op(dev->class->pm, state);
- goto Driver;
- } else if (dev->class->resume) {
- info = "legacy class ";
- callback = dev->class->resume;
- goto End;
- }
- }
- if (dev->bus) {
- if (dev->bus->pm) {
- info = "bus ";
- callback = pm_op(dev->bus->pm, state);
- } else if (dev->bus->resume) {
- info = "legacy bus ";
- callback = dev->bus->resume;
- goto End;
- }
- }
- Driver:
- if (!callback && dev->driver && dev->driver->pm) {
- info = "driver ";
- callback = pm_op(dev->driver->pm, state);
- }
- End:
- error = dpm_run_callback(callback, dev, state, info);
- dev->power.is_suspended = false;
- Unlock:
- device_unlock(dev);
- dpm_watchdog_clear(&wd);
- Complete:
- complete_all(&dev->power.completion);
- TRACE_RESUME(error);
- return error;
- }
- static void async_resume(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = device_resume(dev, pm_transition, true);
- if (error)
- pm_dev_err(dev, pm_transition, " async", error);
- put_device(dev);
- }
- /**
- * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
- * @state: PM transition of the system being carried out.
- *
- * Execute the appropriate "resume" callback for all devices whose status
- * indicates that they are suspended.
- */
- void dpm_resume(pm_message_t state)
- {
- struct device *dev;
- ktime_t starttime = ktime_get();
- trace_suspend_resume(TPS("dpm_resume"), state.event, true);
- might_sleep();
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- async_error = 0;
- list_for_each_entry(dev, &dpm_suspended_list, power.entry) {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_resume, dev);
- }
- }
- while (!list_empty(&dpm_suspended_list)) {
- dev = to_device(dpm_suspended_list.next);
- get_device(dev);
- if (!is_async(dev)) {
- int error;
- mutex_unlock(&dpm_list_mtx);
- error = device_resume(dev, state, false);
- if (error) {
- suspend_stats.failed_resume++;
- dpm_save_failed_step(SUSPEND_RESUME);
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, state, "", error);
- }
- mutex_lock(&dpm_list_mtx);
- }
- if (!list_empty(&dev->power.entry))
- list_move_tail(&dev->power.entry, &dpm_prepared_list);
- put_device(dev);
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- dpm_show_time(starttime, state, NULL);
- cpufreq_resume();
- trace_suspend_resume(TPS("dpm_resume"), state.event, false);
- }
- /**
- * device_complete - Complete a PM transition for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- */
- static void device_complete(struct device *dev, pm_message_t state)
- {
- void (*callback)(struct device *) = NULL;
- char *info = NULL;
- if (dev->power.syscore)
- return;
- device_lock(dev);
- if (dev->pm_domain) {
- info = "completing power domain ";
- callback = dev->pm_domain->ops.complete;
- } else if (dev->type && dev->type->pm) {
- info = "completing type ";
- callback = dev->type->pm->complete;
- } else if (dev->class && dev->class->pm) {
- info = "completing class ";
- callback = dev->class->pm->complete;
- } else if (dev->bus && dev->bus->pm) {
- info = "completing bus ";
- callback = dev->bus->pm->complete;
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "completing driver ";
- callback = dev->driver->pm->complete;
- }
- if (callback) {
- pm_dev_dbg(dev, state, info);
- callback(dev);
- }
- device_unlock(dev);
- pm_runtime_put(dev);
- }
- /**
- * dpm_complete - Complete a PM transition for all non-sysdev devices.
- * @state: PM transition of the system being carried out.
- *
- * Execute the ->complete() callbacks for all devices whose PM status is not
- * DPM_ON (this allows new devices to be registered).
- */
- void dpm_complete(pm_message_t state)
- {
- struct list_head list;
- trace_suspend_resume(TPS("dpm_complete"), state.event, true);
- might_sleep();
- INIT_LIST_HEAD(&list);
- mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_prepared_list)) {
- struct device *dev = to_device(dpm_prepared_list.prev);
- get_device(dev);
- dev->power.is_prepared = false;
- list_move(&dev->power.entry, &list);
- mutex_unlock(&dpm_list_mtx);
- trace_device_pm_callback_start(dev, "", state.event);
- device_complete(dev, state);
- trace_device_pm_callback_end(dev, 0);
- mutex_lock(&dpm_list_mtx);
- put_device(dev);
- }
- list_splice(&list, &dpm_list);
- mutex_unlock(&dpm_list_mtx);
- trace_suspend_resume(TPS("dpm_complete"), state.event, false);
- }
- /**
- * dpm_resume_end - Execute "resume" callbacks and complete system transition.
- * @state: PM transition of the system being carried out.
- *
- * Execute "resume" callbacks for all devices and complete the PM transition of
- * the system.
- */
- void dpm_resume_end(pm_message_t state)
- {
- dpm_resume(state);
- dpm_complete(state);
- }
- EXPORT_SYMBOL_GPL(dpm_resume_end);
- /*------------------------- Suspend routines -------------------------*/
- /**
- * resume_event - Return a "resume" message for given "suspend" sleep state.
- * @sleep_state: PM message representing a sleep state.
- *
- * Return a PM message representing the resume event corresponding to given
- * sleep state.
- */
- static pm_message_t resume_event(pm_message_t sleep_state)
- {
- switch (sleep_state.event) {
- case PM_EVENT_SUSPEND:
- return PMSG_RESUME;
- case PM_EVENT_FREEZE:
- case PM_EVENT_QUIESCE:
- return PMSG_RECOVER;
- case PM_EVENT_HIBERNATE:
- return PMSG_RESTORE;
- }
- return PMSG_ON;
- }
- /**
- * device_suspend_noirq - Execute a "late suspend" callback for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being suspended asynchronously.
- *
- * The driver of @dev will not receive interrupts while this function is being
- * executed.
- */
- static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- TRACE_DEVICE(dev);
- TRACE_SUSPEND(0);
- dpm_wait_for_children(dev, async);
- if (async_error)
- goto Complete;
- if (pm_wakeup_pending()) {
- async_error = -EBUSY;
- goto Complete;
- }
- if (dev->power.syscore || dev->power.direct_complete)
- goto Complete;
- if (dev->pm_domain) {
- info = "noirq power domain ";
- callback = pm_noirq_op(&dev->pm_domain->ops, state);
- } else if (dev->type && dev->type->pm) {
- info = "noirq type ";
- callback = pm_noirq_op(dev->type->pm, state);
- } else if (dev->class && dev->class->pm) {
- info = "noirq class ";
- callback = pm_noirq_op(dev->class->pm, state);
- } else if (dev->bus && dev->bus->pm) {
- info = "noirq bus ";
- callback = pm_noirq_op(dev->bus->pm, state);
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "noirq driver ";
- callback = pm_noirq_op(dev->driver->pm, state);
- }
- error = dpm_run_callback(callback, dev, state, info);
- if (!error)
- dev->power.is_noirq_suspended = true;
- else
- async_error = error;
- Complete:
- complete_all(&dev->power.completion);
- TRACE_SUSPEND(error);
- return error;
- }
- static void async_suspend_noirq(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = __device_suspend_noirq(dev, pm_transition, true);
- if (error) {
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, pm_transition, " async", error);
- }
- put_device(dev);
- }
- static int device_suspend_noirq(struct device *dev)
- {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_suspend_noirq, dev);
- return 0;
- }
- return __device_suspend_noirq(dev, pm_transition, false);
- }
- /**
- * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
- * @state: PM transition of the system being carried out.
- *
- * Prevent device drivers from receiving interrupts and call the "noirq" suspend
- * handlers for all non-sysdev devices.
- */
- int dpm_suspend_noirq(pm_message_t state)
- {
- ktime_t starttime = ktime_get();
- int error = 0;
- trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
- cpuidle_pause();
- device_wakeup_arm_wake_irqs();
- suspend_device_irqs();
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- async_error = 0;
- while (!list_empty(&dpm_late_early_list)) {
- struct device *dev = to_device(dpm_late_early_list.prev);
- get_device(dev);
- mutex_unlock(&dpm_list_mtx);
- error = device_suspend_noirq(dev);
- mutex_lock(&dpm_list_mtx);
- if (error) {
- pm_dev_err(dev, state, " noirq", error);
- dpm_save_failed_dev(dev_name(dev));
- put_device(dev);
- break;
- }
- if (!list_empty(&dev->power.entry))
- list_move(&dev->power.entry, &dpm_noirq_list);
- put_device(dev);
- if (async_error)
- break;
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- if (!error)
- error = async_error;
- if (error) {
- suspend_stats.failed_suspend_noirq++;
- dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
- dpm_resume_noirq(resume_event(state));
- } else {
- dpm_show_time(starttime, state, "noirq");
- }
- trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
- return error;
- }
- /**
- * device_suspend_late - Execute a "late suspend" callback for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being suspended asynchronously.
- *
- * Runtime PM is disabled for @dev while this function is being executed.
- */
- static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- TRACE_DEVICE(dev);
- TRACE_SUSPEND(0);
- __pm_runtime_disable(dev, false);
- dpm_wait_for_children(dev, async);
- if (async_error)
- goto Complete;
- if (pm_wakeup_pending()) {
- async_error = -EBUSY;
- goto Complete;
- }
- if (dev->power.syscore || dev->power.direct_complete)
- goto Complete;
- if (dev->pm_domain) {
- info = "late power domain ";
- callback = pm_late_early_op(&dev->pm_domain->ops, state);
- } else if (dev->type && dev->type->pm) {
- info = "late type ";
- callback = pm_late_early_op(dev->type->pm, state);
- } else if (dev->class && dev->class->pm) {
- info = "late class ";
- callback = pm_late_early_op(dev->class->pm, state);
- } else if (dev->bus && dev->bus->pm) {
- info = "late bus ";
- callback = pm_late_early_op(dev->bus->pm, state);
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "late driver ";
- callback = pm_late_early_op(dev->driver->pm, state);
- }
- error = dpm_run_callback(callback, dev, state, info);
- if (!error)
- dev->power.is_late_suspended = true;
- else
- async_error = error;
- Complete:
- TRACE_SUSPEND(error);
- complete_all(&dev->power.completion);
- return error;
- }
- static void async_suspend_late(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = __device_suspend_late(dev, pm_transition, true);
- if (error) {
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, pm_transition, " async", error);
- }
- put_device(dev);
- }
- static int device_suspend_late(struct device *dev)
- {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_suspend_late, dev);
- return 0;
- }
- return __device_suspend_late(dev, pm_transition, false);
- }
- /**
- * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
- * @state: PM transition of the system being carried out.
- */
- int dpm_suspend_late(pm_message_t state)
- {
- ktime_t starttime = ktime_get();
- int error = 0;
- trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- async_error = 0;
- while (!list_empty(&dpm_suspended_list)) {
- struct device *dev = to_device(dpm_suspended_list.prev);
- get_device(dev);
- mutex_unlock(&dpm_list_mtx);
- error = device_suspend_late(dev);
- mutex_lock(&dpm_list_mtx);
- if (!list_empty(&dev->power.entry))
- list_move(&dev->power.entry, &dpm_late_early_list);
- if (error) {
- pm_dev_err(dev, state, " late", error);
- dpm_save_failed_dev(dev_name(dev));
- put_device(dev);
- break;
- }
- put_device(dev);
- if (async_error)
- break;
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- if (!error)
- error = async_error;
- if (error) {
- suspend_stats.failed_suspend_late++;
- dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
- dpm_resume_early(resume_event(state));
- } else {
- dpm_show_time(starttime, state, "late");
- }
- trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
- return error;
- }
- /**
- * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
- * @state: PM transition of the system being carried out.
- */
- int dpm_suspend_end(pm_message_t state)
- {
- int error = dpm_suspend_late(state);
- if (error)
- return error;
- error = dpm_suspend_noirq(state);
- if (error) {
- dpm_resume_early(resume_event(state));
- return error;
- }
- return 0;
- }
- EXPORT_SYMBOL_GPL(dpm_suspend_end);
- /**
- * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
- * @dev: Device to suspend.
- * @state: PM transition of the system being carried out.
- * @cb: Suspend callback to execute.
- * @info: string description of caller.
- */
- static int legacy_suspend(struct device *dev, pm_message_t state,
- int (*cb)(struct device *dev, pm_message_t state),
- char *info)
- {
- int error;
- ktime_t calltime;
- calltime = initcall_debug_start(dev);
- trace_device_pm_callback_start(dev, info, state.event);
- error = cb(dev, state);
- trace_device_pm_callback_end(dev, error);
- suspend_report_result(cb, error);
- initcall_debug_report(dev, calltime, error, state, info);
- return error;
- }
- /**
- * device_suspend - Execute "suspend" callbacks for given device.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- * @async: If true, the device is being suspended asynchronously.
- */
- static int __device_suspend(struct device *dev, pm_message_t state, bool async)
- {
- pm_callback_t callback = NULL;
- char *info = NULL;
- int error = 0;
- DECLARE_DPM_WATCHDOG_ON_STACK(wd);
- TRACE_DEVICE(dev);
- TRACE_SUSPEND(0);
- dpm_wait_for_children(dev, async);
- if (async_error) {
- dev->power.direct_complete = false;
- goto Complete;
- }
- /*
- * If a device configured to wake up the system from sleep states
- * has been suspended at run time and there's a resume request pending
- * for it, this is equivalent to the device signaling wakeup, so the
- * system suspend operation should be aborted.
- */
- if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
- pm_wakeup_event(dev, 0);
- if (pm_wakeup_pending()) {
- dev->power.direct_complete = false;
- async_error = -EBUSY;
- goto Complete;
- }
- if (dev->power.syscore)
- goto Complete;
- if (dev->power.direct_complete) {
- if (pm_runtime_status_suspended(dev)) {
- pm_runtime_disable(dev);
- if (pm_runtime_status_suspended(dev))
- goto Complete;
- pm_runtime_enable(dev);
- }
- dev->power.direct_complete = false;
- }
- dpm_watchdog_set(&wd, dev);
- device_lock(dev);
- if (dev->pm_domain) {
- info = "power domain ";
- callback = pm_op(&dev->pm_domain->ops, state);
- goto Run;
- }
- if (dev->type && dev->type->pm) {
- info = "type ";
- callback = pm_op(dev->type->pm, state);
- goto Run;
- }
- if (dev->class) {
- if (dev->class->pm) {
- info = "class ";
- callback = pm_op(dev->class->pm, state);
- goto Run;
- } else if (dev->class->suspend) {
- pm_dev_dbg(dev, state, "legacy class ");
- error = legacy_suspend(dev, state, dev->class->suspend,
- "legacy class ");
- goto End;
- }
- }
- if (dev->bus) {
- if (dev->bus->pm) {
- info = "bus ";
- callback = pm_op(dev->bus->pm, state);
- } else if (dev->bus->suspend) {
- pm_dev_dbg(dev, state, "legacy bus ");
- error = legacy_suspend(dev, state, dev->bus->suspend,
- "legacy bus ");
- goto End;
- }
- }
- Run:
- if (!callback && dev->driver && dev->driver->pm) {
- info = "driver ";
- callback = pm_op(dev->driver->pm, state);
- }
- error = dpm_run_callback(callback, dev, state, info);
- End:
- if (!error) {
- struct device *parent = dev->parent;
- dev->power.is_suspended = true;
- if (parent) {
- spin_lock_irq(&parent->power.lock);
- dev->parent->power.direct_complete = false;
- if (dev->power.wakeup_path
- && !dev->parent->power.ignore_children)
- dev->parent->power.wakeup_path = true;
- spin_unlock_irq(&parent->power.lock);
- }
- }
- device_unlock(dev);
- dpm_watchdog_clear(&wd);
- Complete:
- complete_all(&dev->power.completion);
- if (error)
- async_error = error;
- TRACE_SUSPEND(error);
- return error;
- }
- static void async_suspend(void *data, async_cookie_t cookie)
- {
- struct device *dev = (struct device *)data;
- int error;
- error = __device_suspend(dev, pm_transition, true);
- if (error) {
- dpm_save_failed_dev(dev_name(dev));
- pm_dev_err(dev, pm_transition, " async", error);
- }
- put_device(dev);
- }
- static int device_suspend(struct device *dev)
- {
- reinit_completion(&dev->power.completion);
- if (is_async(dev)) {
- get_device(dev);
- async_schedule(async_suspend, dev);
- return 0;
- }
- return __device_suspend(dev, pm_transition, false);
- }
- /**
- * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
- * @state: PM transition of the system being carried out.
- */
- int dpm_suspend(pm_message_t state)
- {
- ktime_t starttime = ktime_get();
- int error = 0;
- trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
- might_sleep();
- cpufreq_suspend();
- mutex_lock(&dpm_list_mtx);
- pm_transition = state;
- async_error = 0;
- while (!list_empty(&dpm_prepared_list)) {
- struct device *dev = to_device(dpm_prepared_list.prev);
- get_device(dev);
- mutex_unlock(&dpm_list_mtx);
- error = device_suspend(dev);
- mutex_lock(&dpm_list_mtx);
- if (error) {
- pm_dev_err(dev, state, "", error);
- dpm_save_failed_dev(dev_name(dev));
- put_device(dev);
- break;
- }
- if (!list_empty(&dev->power.entry))
- list_move(&dev->power.entry, &dpm_suspended_list);
- put_device(dev);
- if (async_error)
- break;
- }
- mutex_unlock(&dpm_list_mtx);
- async_synchronize_full();
- if (!error)
- error = async_error;
- if (error) {
- suspend_stats.failed_suspend++;
- dpm_save_failed_step(SUSPEND_SUSPEND);
- } else
- dpm_show_time(starttime, state, NULL);
- trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
- return error;
- }
- /**
- * device_prepare - Prepare a device for system power transition.
- * @dev: Device to handle.
- * @state: PM transition of the system being carried out.
- *
- * Execute the ->prepare() callback(s) for given device. No new children of the
- * device may be registered after this function has returned.
- */
- static int device_prepare(struct device *dev, pm_message_t state)
- {
- int (*callback)(struct device *) = NULL;
- char *info = NULL;
- int ret = 0;
- if (dev->power.syscore)
- return 0;
- /*
- * If a device's parent goes into runtime suspend at the wrong time,
- * it won't be possible to resume the device. To prevent this we
- * block runtime suspend here, during the prepare phase, and allow
- * it again during the complete phase.
- */
- pm_runtime_get_noresume(dev);
- device_lock(dev);
- dev->power.wakeup_path = device_may_wakeup(dev);
- if (dev->pm_domain) {
- info = "preparing power domain ";
- callback = dev->pm_domain->ops.prepare;
- } else if (dev->type && dev->type->pm) {
- info = "preparing type ";
- callback = dev->type->pm->prepare;
- } else if (dev->class && dev->class->pm) {
- info = "preparing class ";
- callback = dev->class->pm->prepare;
- } else if (dev->bus && dev->bus->pm) {
- info = "preparing bus ";
- callback = dev->bus->pm->prepare;
- }
- if (!callback && dev->driver && dev->driver->pm) {
- info = "preparing driver ";
- callback = dev->driver->pm->prepare;
- }
- if (callback)
- ret = callback(dev);
- device_unlock(dev);
- if (ret < 0) {
- suspend_report_result(callback, ret);
- pm_runtime_put(dev);
- return ret;
- }
- /*
- * A positive return value from ->prepare() means "this device appears
- * to be runtime-suspended and its state is fine, so if it really is
- * runtime-suspended, you can leave it in that state provided that you
- * will do the same thing with all of its descendants". This only
- * applies to suspend transitions, however.
- */
- spin_lock_irq(&dev->power.lock);
- dev->power.direct_complete = ret > 0 && state.event == PM_EVENT_SUSPEND;
- spin_unlock_irq(&dev->power.lock);
- return 0;
- }
- /**
- * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
- * @state: PM transition of the system being carried out.
- *
- * Execute the ->prepare() callback(s) for all devices.
- */
- int dpm_prepare(pm_message_t state)
- {
- int error = 0;
- trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
- might_sleep();
- mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_list)) {
- struct device *dev = to_device(dpm_list.next);
- get_device(dev);
- mutex_unlock(&dpm_list_mtx);
- trace_device_pm_callback_start(dev, "", state.event);
- error = device_prepare(dev, state);
- trace_device_pm_callback_end(dev, error);
- mutex_lock(&dpm_list_mtx);
- if (error) {
- if (error == -EAGAIN) {
- put_device(dev);
- error = 0;
- continue;
- }
- printk(KERN_INFO "PM: Device %s not prepared "
- "for power transition: code %d\n",
- dev_name(dev), error);
- put_device(dev);
- break;
- }
- dev->power.is_prepared = true;
- if (!list_empty(&dev->power.entry))
- list_move_tail(&dev->power.entry, &dpm_prepared_list);
- put_device(dev);
- }
- mutex_unlock(&dpm_list_mtx);
- trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
- return error;
- }
- /**
- * dpm_suspend_start - Prepare devices for PM transition and suspend them.
- * @state: PM transition of the system being carried out.
- *
- * Prepare all non-sysdev devices for system PM transition and execute "suspend"
- * callbacks for them.
- */
- int dpm_suspend_start(pm_message_t state)
- {
- int error;
- error = dpm_prepare(state);
- if (error) {
- suspend_stats.failed_prepare++;
- dpm_save_failed_step(SUSPEND_PREPARE);
- } else
- error = dpm_suspend(state);
- return error;
- }
- EXPORT_SYMBOL_GPL(dpm_suspend_start);
- void __suspend_report_result(const char *function, void *fn, int ret)
- {
- if (ret)
- printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
- }
- EXPORT_SYMBOL_GPL(__suspend_report_result);
- /**
- * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
- * @dev: Device to wait for.
- * @subordinate: Device that needs to wait for @dev.
- */
- int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
- {
- dpm_wait(dev, subordinate->power.async_suspend);
- return async_error;
- }
- EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
- /**
- * dpm_for_each_dev - device iterator.
- * @data: data for the callback.
- * @fn: function to be called for each device.
- *
- * Iterate over devices in dpm_list, and call @fn for each device,
- * passing it @data.
- */
- void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
- {
- struct device *dev;
- if (!fn)
- return;
- device_pm_lock();
- list_for_each_entry(dev, &dpm_list, power.entry)
- fn(dev, data);
- device_pm_unlock();
- }
- EXPORT_SYMBOL_GPL(dpm_for_each_dev);
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