alistair23-linux/include/linux/pm_wakeup.h
Ulf Hansson cf04ce7841 PM / wakeup: Add device_set_wakeup_path() helper to control wakeup path
During system suspend, a driver may find that the wakeup setting is
enabled for its device and therefore configures it to deliver system
wakeup signals.

Additionally, sometimes the driver and its device, relies on some
further consumed resource, like an irqchip or a phy for example, to
stay powered on, as to be able to deliver system wakeup signals.

In general the driver deals with this, via raising an "enable count"
of the consumed resource or via a subsystem specific API, like
irq_set_irq_wake() or enable|disable_irq_wake() for an irqchip.
However, this may not be sufficient in cases when the resource's
device may be attached to a PM domain (genpd for example) or is
handled by a non-trivial middle layer (PCI for example).

To address cases like these, the existing ->dev.power.wakeup_path
status flag is there to help.  As a matter of fact, genpd already
monitors the flag during system suspend and acts accordingly.

However, so far it has not been clear, if anybody else but the PM
core is allowed to set the ->dev.power.wakeup_path status flag,
which is required to make this work.  For this reason, introduce
a new helper function, device_set_wakeup_path() for that.

Typically, a driver that manages a resource needed in the wakeup path
should call device_set_wakeup_path() from its ->suspend() or
->suspend_late() callback.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-09 13:09:17 +01:00

229 lines
6.8 KiB
C

/*
* pm_wakeup.h - Power management wakeup interface
*
* Copyright (C) 2008 Alan Stern
* Copyright (C) 2010 Rafael J. Wysocki, Novell Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _LINUX_PM_WAKEUP_H
#define _LINUX_PM_WAKEUP_H
#ifndef _DEVICE_H_
# error "please don't include this file directly"
#endif
#include <linux/types.h>
struct wake_irq;
/**
* struct wakeup_source - Representation of wakeup sources
*
* @name: Name of the wakeup source
* @entry: Wakeup source list entry
* @lock: Wakeup source lock
* @wakeirq: Optional device specific wakeirq
* @timer: Wakeup timer list
* @timer_expires: Wakeup timer expiration
* @total_time: Total time this wakeup source has been active.
* @max_time: Maximum time this wakeup source has been continuously active.
* @last_time: Monotonic clock when the wakeup source's was touched last time.
* @prevent_sleep_time: Total time this source has been preventing autosleep.
* @event_count: Number of signaled wakeup events.
* @active_count: Number of times the wakeup source was activated.
* @relax_count: Number of times the wakeup source was deactivated.
* @expire_count: Number of times the wakeup source's timeout has expired.
* @wakeup_count: Number of times the wakeup source might abort suspend.
* @active: Status of the wakeup source.
* @has_timeout: The wakeup source has been activated with a timeout.
*/
struct wakeup_source {
const char *name;
struct list_head entry;
spinlock_t lock;
struct wake_irq *wakeirq;
struct timer_list timer;
unsigned long timer_expires;
ktime_t total_time;
ktime_t max_time;
ktime_t last_time;
ktime_t start_prevent_time;
ktime_t prevent_sleep_time;
unsigned long event_count;
unsigned long active_count;
unsigned long relax_count;
unsigned long expire_count;
unsigned long wakeup_count;
bool active:1;
bool autosleep_enabled:1;
};
#ifdef CONFIG_PM_SLEEP
/*
* Changes to device_may_wakeup take effect on the next pm state change.
*/
static inline bool device_can_wakeup(struct device *dev)
{
return dev->power.can_wakeup;
}
static inline bool device_may_wakeup(struct device *dev)
{
return dev->power.can_wakeup && !!dev->power.wakeup;
}
static inline void device_set_wakeup_path(struct device *dev)
{
dev->power.wakeup_path = true;
}
/* drivers/base/power/wakeup.c */
extern void wakeup_source_prepare(struct wakeup_source *ws, const char *name);
extern struct wakeup_source *wakeup_source_create(const char *name);
extern void wakeup_source_drop(struct wakeup_source *ws);
extern void wakeup_source_destroy(struct wakeup_source *ws);
extern void wakeup_source_add(struct wakeup_source *ws);
extern void wakeup_source_remove(struct wakeup_source *ws);
extern struct wakeup_source *wakeup_source_register(const char *name);
extern void wakeup_source_unregister(struct wakeup_source *ws);
extern int device_wakeup_enable(struct device *dev);
extern int device_wakeup_disable(struct device *dev);
extern void device_set_wakeup_capable(struct device *dev, bool capable);
extern int device_init_wakeup(struct device *dev, bool val);
extern int device_set_wakeup_enable(struct device *dev, bool enable);
extern void __pm_stay_awake(struct wakeup_source *ws);
extern void pm_stay_awake(struct device *dev);
extern void __pm_relax(struct wakeup_source *ws);
extern void pm_relax(struct device *dev);
extern void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard);
extern void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard);
#else /* !CONFIG_PM_SLEEP */
static inline void device_set_wakeup_capable(struct device *dev, bool capable)
{
dev->power.can_wakeup = capable;
}
static inline bool device_can_wakeup(struct device *dev)
{
return dev->power.can_wakeup;
}
static inline void wakeup_source_prepare(struct wakeup_source *ws,
const char *name) {}
static inline struct wakeup_source *wakeup_source_create(const char *name)
{
return NULL;
}
static inline void wakeup_source_drop(struct wakeup_source *ws) {}
static inline void wakeup_source_destroy(struct wakeup_source *ws) {}
static inline void wakeup_source_add(struct wakeup_source *ws) {}
static inline void wakeup_source_remove(struct wakeup_source *ws) {}
static inline struct wakeup_source *wakeup_source_register(const char *name)
{
return NULL;
}
static inline void wakeup_source_unregister(struct wakeup_source *ws) {}
static inline int device_wakeup_enable(struct device *dev)
{
dev->power.should_wakeup = true;
return 0;
}
static inline int device_wakeup_disable(struct device *dev)
{
dev->power.should_wakeup = false;
return 0;
}
static inline int device_set_wakeup_enable(struct device *dev, bool enable)
{
dev->power.should_wakeup = enable;
return 0;
}
static inline int device_init_wakeup(struct device *dev, bool val)
{
device_set_wakeup_capable(dev, val);
device_set_wakeup_enable(dev, val);
return 0;
}
static inline bool device_may_wakeup(struct device *dev)
{
return dev->power.can_wakeup && dev->power.should_wakeup;
}
static inline void device_set_wakeup_path(struct device *dev) {}
static inline void __pm_stay_awake(struct wakeup_source *ws) {}
static inline void pm_stay_awake(struct device *dev) {}
static inline void __pm_relax(struct wakeup_source *ws) {}
static inline void pm_relax(struct device *dev) {}
static inline void pm_wakeup_ws_event(struct wakeup_source *ws,
unsigned int msec, bool hard) {}
static inline void pm_wakeup_dev_event(struct device *dev, unsigned int msec,
bool hard) {}
#endif /* !CONFIG_PM_SLEEP */
static inline void wakeup_source_init(struct wakeup_source *ws,
const char *name)
{
wakeup_source_prepare(ws, name);
wakeup_source_add(ws);
}
static inline void wakeup_source_trash(struct wakeup_source *ws)
{
wakeup_source_remove(ws);
wakeup_source_drop(ws);
}
static inline void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec)
{
return pm_wakeup_ws_event(ws, msec, false);
}
static inline void pm_wakeup_event(struct device *dev, unsigned int msec)
{
return pm_wakeup_dev_event(dev, msec, false);
}
static inline void pm_wakeup_hard_event(struct device *dev)
{
return pm_wakeup_dev_event(dev, 0, true);
}
#endif /* _LINUX_PM_WAKEUP_H */