remarkable-linux/include/linux/pm_runtime.h
Rafael J. Wysocki 2f60ba706b i2c: Fix bus-level power management callbacks
There are three issues with the i2c bus type's power management
callbacks at the moment.  First, they don't include any hibernate
callbacks, although they should at least include the .restore()
callback (there's no guarantee that the driver will be present in
memory before loading the image kernel and we must restore the
pre-hibernation state of the device).  Second, the "legacy"
callbacks are not going to be invoked by the PM core since the bus
type's pm object is not NULL.  Finally, the system sleep PM
(ie. suspend/resume) callbacks don't check if the device has been
already suspended at run time, in which case they should skip
suspending it.  Also, it looks like the i2c bus type can use the
generic subsystem-level runtime PM callbacks.

For these reasons, rework the system sleep PM callbacks provided by
the i2c bus type to handle hibernation correctly and to invoke the
"legacy" callbacks for drivers that provide them.  In addition to
that make the i2c bus type use the generic subsystem-level runtime
PM callbacks.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
2010-05-10 23:09:30 +02:00

144 lines
4.6 KiB
C

/*
* pm_runtime.h - Device run-time power management helper functions.
*
* Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>
*
* This file is released under the GPLv2.
*/
#ifndef _LINUX_PM_RUNTIME_H
#define _LINUX_PM_RUNTIME_H
#include <linux/device.h>
#include <linux/pm.h>
#ifdef CONFIG_PM_RUNTIME
extern struct workqueue_struct *pm_wq;
extern int pm_runtime_idle(struct device *dev);
extern int pm_runtime_suspend(struct device *dev);
extern int pm_runtime_resume(struct device *dev);
extern int pm_request_idle(struct device *dev);
extern int pm_schedule_suspend(struct device *dev, unsigned int delay);
extern int pm_request_resume(struct device *dev);
extern int __pm_runtime_get(struct device *dev, bool sync);
extern int __pm_runtime_put(struct device *dev, bool sync);
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 int pm_generic_runtime_idle(struct device *dev);
extern int pm_generic_runtime_suspend(struct device *dev);
extern int pm_generic_runtime_resume(struct device *dev);
static inline bool pm_children_suspended(struct device *dev)
{
return dev->power.ignore_children
|| !atomic_read(&dev->power.child_count);
}
static inline void pm_suspend_ignore_children(struct device *dev, bool enable)
{
dev->power.ignore_children = enable;
}
static inline void pm_runtime_get_noresume(struct device *dev)
{
atomic_inc(&dev->power.usage_count);
}
static inline void pm_runtime_put_noidle(struct device *dev)
{
atomic_add_unless(&dev->power.usage_count, -1, 0);
}
static inline bool device_run_wake(struct device *dev)
{
return dev->power.run_wake;
}
static inline void device_set_run_wake(struct device *dev, bool enable)
{
dev->power.run_wake = enable;
}
static inline bool pm_runtime_suspended(struct device *dev)
{
return dev->power.runtime_status == RPM_SUSPENDED;
}
#else /* !CONFIG_PM_RUNTIME */
static inline int pm_runtime_idle(struct device *dev) { return -ENOSYS; }
static inline int pm_runtime_suspend(struct device *dev) { return -ENOSYS; }
static inline int pm_runtime_resume(struct device *dev) { return 0; }
static inline int pm_request_idle(struct device *dev) { return -ENOSYS; }
static inline int pm_schedule_suspend(struct device *dev, unsigned int delay)
{
return -ENOSYS;
}
static inline int pm_request_resume(struct device *dev) { return 0; }
static inline int __pm_runtime_get(struct device *dev, bool sync) { return 1; }
static inline int __pm_runtime_put(struct device *dev, bool sync) { return 0; }
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 bool pm_children_suspended(struct device *dev) { return false; }
static inline void pm_suspend_ignore_children(struct device *dev, bool en) {}
static inline void pm_runtime_get_noresume(struct device *dev) {}
static inline void pm_runtime_put_noidle(struct device *dev) {}
static inline bool device_run_wake(struct device *dev) { return false; }
static inline void device_set_run_wake(struct device *dev, bool enable) {}
static inline bool pm_runtime_suspended(struct device *dev) { return false; }
static inline int pm_generic_runtime_idle(struct device *dev) { return 0; }
static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
#endif /* !CONFIG_PM_RUNTIME */
static inline int pm_runtime_get(struct device *dev)
{
return __pm_runtime_get(dev, false);
}
static inline int pm_runtime_get_sync(struct device *dev)
{
return __pm_runtime_get(dev, true);
}
static inline int pm_runtime_put(struct device *dev)
{
return __pm_runtime_put(dev, false);
}
static inline int pm_runtime_put_sync(struct device *dev)
{
return __pm_runtime_put(dev, true);
}
static inline int pm_runtime_set_active(struct device *dev)
{
return __pm_runtime_set_status(dev, RPM_ACTIVE);
}
static inline void pm_runtime_set_suspended(struct device *dev)
{
__pm_runtime_set_status(dev, RPM_SUSPENDED);
}
static inline void pm_runtime_disable(struct device *dev)
{
__pm_runtime_disable(dev, true);
}
#endif