linux/drivers/base/power/main.c

// SPDX-License-Identifier: GPL-2.0
/*
 * drivers/base/power/main.c - Where the driver meets power management.
 *
 * Copyright (c) 2003 Patrick Mochel
 * Copyright (c) 2003 Open Source Development Lab
 *
 * 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.
 */

#define pr_fmt(fmt) …
#define dev_fmt …

#include <linux/device.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/sched/debug.h>
#include <linux/async.h>
#include <linux/suspend.h>
#include <trace/events/power.h>
#include <linux/cpufreq.h>
#include <linux/devfreq.h>
#include <linux/timer.h>

#include "../base.h"
#include "power.h"

pm_callback_t;

#define list_for_each_entry_rcu_locked(pos, head, member) …

/*
 * 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(…);
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);

static DEFINE_MUTEX(dpm_list_mtx);
static pm_message_t pm_transition;

static int async_error;

static const char *pm_verb(int event)
{ … }

/**
 * device_pm_sleep_init - Initialize system suspend-related device fields.
 * @dev: Device object being initialized.
 */
void device_pm_sleep_init(struct device *dev)
{ … }

/**
 * device_pm_lock - Lock the list of active devices used by the PM core.
 */
void device_pm_lock(void)
{ … }

/**
 * device_pm_unlock - Unlock the list of active devices used by the PM core.
 */
void device_pm_unlock(void)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

static ktime_t initcall_debug_start(struct device *dev, void *cb)
{ … }

static void initcall_debug_report(struct device *dev, ktime_t calltime,
				  void *cb, int error)
{ … }

/**
 * 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)
{ … }

static int dpm_wait_fn(struct device *dev, void *async_ptr)
{ … }

static void dpm_wait_for_children(struct device *dev, bool async)
{ … }

static void dpm_wait_for_suppliers(struct device *dev, bool async)
{ … }

static bool dpm_wait_for_superior(struct device *dev, bool async)
{ … }

static void dpm_wait_for_consumers(struct device *dev, bool async)
{ … }

static void dpm_wait_for_subordinate(struct device *dev, bool async)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info)
{ … }

static void pm_dev_err(struct device *dev, pm_message_t state, const char *info,
			int error)
{ … }

static void dpm_show_time(ktime_t starttime, pm_message_t state, int error,
			  const char *info)
{ … }

static int dpm_run_callback(pm_callback_t cb, struct device *dev,
			    pm_message_t state, const char *info)
{ … }

#ifdef CONFIG_DPM_WATCHDOG
struct dpm_watchdog { … };

#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) …

/**
 * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
 * @t: The timer that PM watchdog depends on.
 *
 * 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(struct timer_list *t)
{ … }

/**
 * 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)
{ … }

/**
 * dpm_watchdog_clear - Disable suspend/resume watchdog.
 * @wd: Watchdog to disable.
 */
static void dpm_watchdog_clear(struct dpm_watchdog *wd)
{ … }
#else
#define DECLARE_DPM_WATCHDOG_ON_STACK …
#define dpm_watchdog_set …
#define dpm_watchdog_clear …
#endif

/*------------------------- Resume routines -------------------------*/

/**
 * dev_pm_skip_resume - System-wide device resume optimization check.
 * @dev: Target device.
 *
 * Return:
 * - %false if the transition under way is RESTORE.
 * - Return value of dev_pm_skip_suspend() if the transition under way is THAW.
 * - The logical negation of %power.must_resume otherwise (that is, when the
 *   transition under way is RESUME).
 */
bool dev_pm_skip_resume(struct device *dev)
{ … }

static bool is_async(struct device *dev)
{ … }

static bool dpm_async_fn(struct device *dev, async_func_t func)
{ … }

/**
 * device_resume_noirq - Execute a "noirq 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 void device_resume_noirq(struct device *dev, pm_message_t state, bool async)
{ … }

static void async_resume_noirq(void *data, async_cookie_t cookie)
{ … }

static void dpm_noirq_resume_devices(pm_message_t state)
{ … }

/**
 * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
 * @state: PM transition of the system being carried out.
 *
 * Invoke the "noirq" resume callbacks for all devices in dpm_noirq_list and
 * allow device drivers' interrupt handlers to be called.
 */
void dpm_resume_noirq(pm_message_t state)
{ … }

/**
 * 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 void device_resume_early(struct device *dev, pm_message_t state, bool async)
{ … }

static void async_resume_early(void *data, async_cookie_t cookie)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * 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 void device_resume(struct device *dev, pm_message_t state, bool async)
{ … }

static void async_resume(void *data, async_cookie_t cookie)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);


/*------------------------- 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)
{ … }

static void dpm_superior_set_must_resume(struct device *dev)
{ … }

/**
 * device_suspend_noirq - Execute a "noirq 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)
{ … }

static void async_suspend_noirq(void *data, async_cookie_t cookie)
{ … }

static int dpm_noirq_suspend_devices(pm_message_t state)
{ … }

/**
 * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
 * @state: PM transition of the system being carried out.
 *
 * Prevent device drivers' interrupt handlers from being called and invoke
 * "noirq" suspend callbacks for all non-sysdev devices.
 */
int dpm_suspend_noirq(pm_message_t state)
{ … }

static void dpm_propagate_wakeup_to_parent(struct device *dev)
{ … }

/**
 * 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)
{ … }

static void async_suspend_late(void *data, async_cookie_t cookie)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * 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),
			  const char *info)
{ … }

static void dpm_clear_superiors_direct_complete(struct device *dev)
{ … }

/**
 * 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)
{ … }

static void async_suspend(void *data, async_cookie_t cookie)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL_GPL(…);

void __suspend_report_result(const char *function, struct device *dev, void *fn, int ret)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
 * @subordinate: Device that needs to wait for @dev.
 * @dev: Device to wait for.
 */
int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * 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 *))
{ … }
EXPORT_SYMBOL_GPL(…);

static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
{ … }

void device_pm_check_callbacks(struct device *dev)
{ … }

bool dev_pm_skip_suspend(struct device *dev)
{ … }