include/linux/pm_runtime.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * pm_runtime.h - Device run-time power management helper functions.
 *
 * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>
 */

#ifndef _LINUX_PM_RUNTIME_H
#define _LINUX_PM_RUNTIME_H

#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/pm.h>

#include <linux/jiffies.h>

/* Runtime PM flag argument bits */
#define RPM_ASYNC		0x01	/* Request is asynchronous */
#define RPM_NOWAIT		0x02	/* Don't wait for concurrent
					    state change */
#define RPM_GET_PUT		0x04	/* Increment/decrement the
					    usage_count */
#define RPM_AUTO		0x08	/* Use autosuspend_delay */

#ifdef CONFIG_PM
extern struct workqueue_struct *pm_wq;

static inline bool queue_pm_work(struct work_struct *work)
{
	return queue_work(pm_wq, work);
}

extern int pm_generic_runtime_suspend(struct device *dev);
extern int pm_generic_runtime_resume(struct device *dev);
extern int pm_runtime_force_suspend(struct device *dev);
extern int pm_runtime_force_resume(struct device *dev);

extern int __pm_runtime_idle(struct device *dev, int rpmflags);
extern int __pm_runtime_suspend(struct device *dev, int rpmflags);
extern int __pm_runtime_resume(struct device *dev, int rpmflags);
extern int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count);
extern int pm_schedule_suspend(struct device *dev, unsigned int delay);
extern int __pm_runtime_set_status(struct device *dev, unsigned int status);
extern int pm_runtime_barrier(struct device *dev);
extern void pm_runtime_enable(struct device *dev);
extern void __pm_runtime_disable(struct device *dev, bool check_resume);
extern void pm_runtime_allow(struct device *dev);
extern void pm_runtime_forbid(struct device *dev);
extern void pm_runtime_no_callbacks(struct device *dev);
extern void pm_runtime_irq_safe(struct device *dev);
extern void __pm_runtime_use_autosuspend(struct device *dev, bool use);
extern void pm_runtime_set_autosuspend_delay(struct device *dev, int delay);
extern u64 pm_runtime_autosuspend_expiration(struct device *dev);
extern void pm_runtime_update_max_time_suspended(struct device *dev,
						 s64 delta_ns);
extern void pm_runtime_set_memalloc_noio(struct device *dev, bool enable);
extern void pm_runtime_get_suppliers(struct device *dev);
extern void pm_runtime_put_suppliers(struct device *dev);
extern void pm_runtime_new_link(struct device *dev);
extern void pm_runtime_drop_link(struct device_link *link);

/**
 * pm_runtime_get_if_in_use - Conditionally bump up runtime PM usage counter.
 * @dev: Target device.
 *
 * Increment the runtime PM usage counter of @dev if its runtime PM status is
 * %RPM_ACTIVE and its runtime PM usage counter is greater than 0.
 */
static inline int pm_runtime_get_if_in_use(struct device *dev)
{
	return pm_runtime_get_if_active(dev, false);
}

/**
 * pm_suspend_ignore_children - Set runtime PM behavior regarding children.
 * @dev: Target device.
 * @enable: Whether or not to ignore possible dependencies on children.
 *
 * The dependencies of @dev on its children will not be taken into account by
 * the runtime PM framework going forward if @enable is %true, or they will
 * be taken into account otherwise.
 */
static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
{
	dev->power.ignore_children = enable;
}

/**
 * pm_runtime_get_noresume - Bump up runtime PM usage counter of a device.
 * @dev: Target device.
 */
static inline void pm_runtime_get_noresume(struct device *dev)
{
	atomic_inc(&dev->power.usage_count);
}

/**
 * pm_runtime_put_noidle - Drop runtime PM usage counter of a device.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev unless it is 0 already.
 */
static inline void pm_runtime_put_noidle(struct device *dev)
{
	atomic_add_unless(&dev->power.usage_count, -1, 0);
}

/**
 * pm_runtime_suspended - Check whether or not a device is runtime-suspended.
 * @dev: Target device.
 *
 * Return %true if runtime PM is enabled for @dev and its runtime PM status is
 * %RPM_SUSPENDED, or %false otherwise.
 *
 * Note that the return value of this function can only be trusted if it is
 * called under the runtime PM lock of @dev or under conditions in which
 * runtime PM cannot be either disabled or enabled for @dev and its runtime PM
 * status cannot change.
 */
static inline bool pm_runtime_suspended(struct device *dev)
{
	return dev->power.runtime_status == RPM_SUSPENDED
		&& !dev->power.disable_depth;
}

/**
 * pm_runtime_active - Check whether or not a device is runtime-active.
 * @dev: Target device.
 *
 * Return %true if runtime PM is enabled for @dev and its runtime PM status is
 * %RPM_ACTIVE, or %false otherwise.
 *
 * Note that the return value of this function can only be trusted if it is
 * called under the runtime PM lock of @dev or under conditions in which
 * runtime PM cannot be either disabled or enabled for @dev and its runtime PM
 * status cannot change.
 */
static inline bool pm_runtime_active(struct device *dev)
{
	return dev->power.runtime_status == RPM_ACTIVE
		|| dev->power.disable_depth;
}

/**
 * pm_runtime_status_suspended - Check if runtime PM status is "suspended".
 * @dev: Target device.
 *
 * Return %true if the runtime PM status of @dev is %RPM_SUSPENDED, or %false
 * otherwise, regardless of whether or not runtime PM has been enabled for @dev.
 *
 * Note that the return value of this function can only be trusted if it is
 * called under the runtime PM lock of @dev or under conditions in which the
 * runtime PM status of @dev cannot change.
 */
static inline bool pm_runtime_status_suspended(struct device *dev)
{
	return dev->power.runtime_status == RPM_SUSPENDED;
}

/**
 * pm_runtime_enabled - Check if runtime PM is enabled.
 * @dev: Target device.
 *
 * Return %true if runtime PM is enabled for @dev or %false otherwise.
 *
 * Note that the return value of this function can only be trusted if it is
 * called under the runtime PM lock of @dev or under conditions in which
 * runtime PM cannot be either disabled or enabled for @dev.
 */
static inline bool pm_runtime_enabled(struct device *dev)
{
	return !dev->power.disable_depth;
}

/**
 * pm_runtime_has_no_callbacks - Check if runtime PM callbacks may be present.
 * @dev: Target device.
 *
 * Return %true if @dev is a special device without runtime PM callbacks or
 * %false otherwise.
 */
static inline bool pm_runtime_has_no_callbacks(struct device *dev)
{
	return dev->power.no_callbacks;
}

/**
 * pm_runtime_mark_last_busy - Update the last access time of a device.
 * @dev: Target device.
 *
 * Update the last access time of @dev used by the runtime PM autosuspend
 * mechanism to the current time as returned by ktime_get_mono_fast_ns().
 */
static inline void pm_runtime_mark_last_busy(struct device *dev)
{
	WRITE_ONCE(dev->power.last_busy, ktime_get_mono_fast_ns());
}

/**
 * pm_runtime_is_irq_safe - Check if runtime PM can work in interrupt context.
 * @dev: Target device.
 *
 * Return %true if @dev has been marked as an "IRQ-safe" device (with respect
 * to runtime PM), in which case its runtime PM callabcks can be expected to
 * work correctly when invoked from interrupt handlers.
 */
static inline bool pm_runtime_is_irq_safe(struct device *dev)
{
	return dev->power.irq_safe;
}

extern u64 pm_runtime_suspended_time(struct device *dev);

#else /* !CONFIG_PM */

static inline bool queue_pm_work(struct work_struct *work) { return false; }

static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
static inline int pm_runtime_force_suspend(struct device *dev) { return 0; }
static inline int pm_runtime_force_resume(struct device *dev) { return 0; }

static inline int __pm_runtime_idle(struct device *dev, int rpmflags)
{
	return -ENOSYS;
}
static inline int __pm_runtime_suspend(struct device *dev, int rpmflags)
{
	return -ENOSYS;
}
static inline int __pm_runtime_resume(struct device *dev, int rpmflags)
{
	return 1;
}
static inline int pm_schedule_suspend(struct device *dev, unsigned int delay)
{
	return -ENOSYS;
}
static inline int pm_runtime_get_if_in_use(struct device *dev)
{
	return -EINVAL;
}
static inline int pm_runtime_get_if_active(struct device *dev,
					   bool ign_usage_count)
{
	return -EINVAL;
}
static inline int __pm_runtime_set_status(struct device *dev,
					    unsigned int status) { return 0; }
static inline int pm_runtime_barrier(struct device *dev) { return 0; }
static inline void pm_runtime_enable(struct device *dev) {}
static inline void __pm_runtime_disable(struct device *dev, bool c) {}
static inline void pm_runtime_allow(struct device *dev) {}
static inline void pm_runtime_forbid(struct device *dev) {}

static inline void pm_suspend_ignore_children(struct device *dev, bool enable) {}
static inline void pm_runtime_get_noresume(struct device *dev) {}
static inline void pm_runtime_put_noidle(struct device *dev) {}
static inline bool pm_runtime_suspended(struct device *dev) { return false; }
static inline bool pm_runtime_active(struct device *dev) { return true; }
static inline bool pm_runtime_status_suspended(struct device *dev) { return false; }
static inline bool pm_runtime_enabled(struct device *dev) { return false; }

static inline void pm_runtime_no_callbacks(struct device *dev) {}
static inline void pm_runtime_irq_safe(struct device *dev) {}
static inline bool pm_runtime_is_irq_safe(struct device *dev) { return false; }

static inline bool pm_runtime_has_no_callbacks(struct device *dev) { return false; }
static inline void pm_runtime_mark_last_busy(struct device *dev) {}
static inline void __pm_runtime_use_autosuspend(struct device *dev,
						bool use) {}
static inline void pm_runtime_set_autosuspend_delay(struct device *dev,
						int delay) {}
static inline u64 pm_runtime_autosuspend_expiration(
				struct device *dev) { return 0; }
static inline void pm_runtime_set_memalloc_noio(struct device *dev,
						bool enable){}
static inline void pm_runtime_get_suppliers(struct device *dev) {}
static inline void pm_runtime_put_suppliers(struct device *dev) {}
static inline void pm_runtime_new_link(struct device *dev) {}
static inline void pm_runtime_drop_link(struct device_link *link) {}

#endif /* !CONFIG_PM */

/**
 * pm_runtime_idle - Conditionally set up autosuspend of a device or suspend it.
 * @dev: Target device.
 *
 * Invoke the "idle check" callback of @dev and, depending on its return value,
 * set up autosuspend of @dev or suspend it (depending on whether or not
 * autosuspend has been enabled for it).
 */
static inline int pm_runtime_idle(struct device *dev)
{
	return __pm_runtime_idle(dev, 0);
}

/**
 * pm_runtime_suspend - Suspend a device synchronously.
 * @dev: Target device.
 */
static inline int pm_runtime_suspend(struct device *dev)
{
	return __pm_runtime_suspend(dev, 0);
}

/**
 * pm_runtime_autosuspend - Set up autosuspend of a device or suspend it.
 * @dev: Target device.
 *
 * Set up autosuspend of @dev or suspend it (depending on whether or not
 * autosuspend is enabled for it) without engaging its "idle check" callback.
 */
static inline int pm_runtime_autosuspend(struct device *dev)
{
	return __pm_runtime_suspend(dev, RPM_AUTO);
}

/**
 * pm_runtime_resume - Resume a device synchronously.
 * @dev: Target device.
 */
static inline int pm_runtime_resume(struct device *dev)
{
	return __pm_runtime_resume(dev, 0);
}

/**
 * pm_request_idle - Queue up "idle check" execution for a device.
 * @dev: Target device.
 *
 * Queue up a work item to run an equivalent of pm_runtime_idle() for @dev
 * asynchronously.
 */
static inline int pm_request_idle(struct device *dev)
{
	return __pm_runtime_idle(dev, RPM_ASYNC);
}

/**
 * pm_request_resume - Queue up runtime-resume of a device.
 * @dev: Target device.
 */
static inline int pm_request_resume(struct device *dev)
{
	return __pm_runtime_resume(dev, RPM_ASYNC);
}

/**
 * pm_request_autosuspend - Queue up autosuspend of a device.
 * @dev: Target device.
 *
 * Queue up a work item to run an equivalent pm_runtime_autosuspend() for @dev
 * asynchronously.
 */
static inline int pm_request_autosuspend(struct device *dev)
{
	return __pm_runtime_suspend(dev, RPM_ASYNC | RPM_AUTO);
}

/**
 * pm_runtime_get - Bump up usage counter and queue up resume of a device.
 * @dev: Target device.
 *
 * Bump up the runtime PM usage counter of @dev and queue up a work item to
 * carry out runtime-resume of it.
 */
static inline int pm_runtime_get(struct device *dev)
{
	return __pm_runtime_resume(dev, RPM_GET_PUT | RPM_ASYNC);
}

/**
 * pm_runtime_get_sync - Bump up usage counter of a device and resume it.
 * @dev: Target device.
 *
 * Bump up the runtime PM usage counter of @dev and carry out runtime-resume of
 * it synchronously.
 *
 * The possible return values of this function are the same as for
 * pm_runtime_resume() and the runtime PM usage counter of @dev remains
 * incremented in all cases, even if it returns an error code.
 */
static inline int pm_runtime_get_sync(struct device *dev)
{
	return __pm_runtime_resume(dev, RPM_GET_PUT);
}

/**
 * pm_runtime_resume_and_get - Bump up usage counter of a device and resume it.
 * @dev: Target device.
 *
 * Resume @dev synchronously and if that is successful, increment its runtime
 * PM usage counter. Return 0 if the runtime PM usage counter of @dev has been
 * incremented or a negative error code otherwise.
 */
static inline int pm_runtime_resume_and_get(struct device *dev)
{
	int ret;

	ret = __pm_runtime_resume(dev, RPM_GET_PUT);
	if (ret < 0) {
		pm_runtime_put_noidle(dev);
		return ret;
	}

	return 0;
}

/**
 * pm_runtime_put - Drop device usage counter and queue up "idle check" if 0.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev and if it turns out to be
 * equal to 0, queue up a work item for @dev like in pm_request_idle().
 */
static inline int pm_runtime_put(struct device *dev)
{
	return __pm_runtime_idle(dev, RPM_GET_PUT | RPM_ASYNC);
}

/**
 * pm_runtime_put_autosuspend - Drop device usage counter and queue autosuspend if 0.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev and if it turns out to be
 * equal to 0, queue up a work item for @dev like in pm_request_autosuspend().
 */
static inline int pm_runtime_put_autosuspend(struct device *dev)
{
	return __pm_runtime_suspend(dev,
	    RPM_GET_PUT | RPM_ASYNC | RPM_AUTO);
}

/**
 * pm_runtime_put_sync - Drop device usage counter and run "idle check" if 0.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev and if it turns out to be
 * equal to 0, invoke the "idle check" callback of @dev and, depending on its
 * return value, set up autosuspend of @dev or suspend it (depending on whether
 * or not autosuspend has been enabled for it).
 *
 * The possible return values of this function are the same as for
 * pm_runtime_idle() and the runtime PM usage counter of @dev remains
 * decremented in all cases, even if it returns an error code.
 */
static inline int pm_runtime_put_sync(struct device *dev)
{
	return __pm_runtime_idle(dev, RPM_GET_PUT);
}

/**
 * pm_runtime_put_sync_suspend - Drop device usage counter and suspend if 0.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev and if it turns out to be
 * equal to 0, carry out runtime-suspend of @dev synchronously.
 *
 * The possible return values of this function are the same as for
 * pm_runtime_suspend() and the runtime PM usage counter of @dev remains
 * decremented in all cases, even if it returns an error code.
 */
static inline int pm_runtime_put_sync_suspend(struct device *dev)
{
	return __pm_runtime_suspend(dev, RPM_GET_PUT);
}

/**
 * pm_runtime_put_sync_autosuspend - Drop device usage counter and autosuspend if 0.
 * @dev: Target device.
 *
 * Decrement the runtime PM usage counter of @dev and if it turns out to be
 * equal to 0, set up autosuspend of @dev or suspend it synchronously (depending
 * on whether or not autosuspend has been enabled for it).
 *
 * The possible return values of this function are the same as for
 * pm_runtime_autosuspend() and the runtime PM usage counter of @dev remains
 * decremented in all cases, even if it returns an error code.
 */
static inline int pm_runtime_put_sync_autosuspend(struct device *dev)
{
	return __pm_runtime_suspend(dev, RPM_GET_PUT | RPM_AUTO);
}

/**
 * pm_runtime_set_active - Set runtime PM status to "active".
 * @dev: Target device.
 *
 * Set the runtime PM status of @dev to %RPM_ACTIVE and ensure that dependencies
 * of it will be taken into account.
 *
 * It is not valid to call this function for devices with runtime PM enabled.
 */
static inline int pm_runtime_set_active(struct device *dev)
{
	return __pm_runtime_set_status(dev, RPM_ACTIVE);
}

/**
 * pm_runtime_set_suspended - Set runtime PM status to "suspended".
 * @dev: Target device.
 *
 * Set the runtime PM status of @dev to %RPM_SUSPENDED and ensure that
 * dependencies of it will be taken into account.
 *
 * It is not valid to call this function for devices with runtime PM enabled.
 */
static inline int pm_runtime_set_suspended(struct device *dev)
{
	return __pm_runtime_set_status(dev, RPM_SUSPENDED);
}

/**
 * pm_runtime_disable - Disable runtime PM for a device.
 * @dev: Target device.
 *
 * Prevent the runtime PM framework from working with @dev (by incrementing its
 * "blocking" counter).
 *
 * For each invocation of this function for @dev there must be a matching
 * pm_runtime_enable() call in order for runtime PM to be enabled for it.
 */
static inline void pm_runtime_disable(struct device *dev)
{
	__pm_runtime_disable(dev, true);
}

/**
 * pm_runtime_use_autosuspend - Allow autosuspend to be used for a device.
 * @dev: Target device.
 *
 * Allow the runtime PM autosuspend mechanism to be used for @dev whenever
 * requested (or "autosuspend" will be handled as direct runtime-suspend for
 * it).
 */
static inline void pm_runtime_use_autosuspend(struct device *dev)
{
	__pm_runtime_use_autosuspend(dev, true);
}

/**
 * pm_runtime_dont_use_autosuspend - Prevent autosuspend from being used.
 * @dev: Target device.
 *
 * Prevent the runtime PM autosuspend mechanism from being used for @dev which
 * means that "autosuspend" will be handled as direct runtime-suspend for it
 * going forward.
 */
static inline void pm_runtime_dont_use_autosuspend(struct device *dev)
{
	__pm_runtime_use_autosuspend(dev, false);
}

#endif