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authorRafael J. Wysocki <rjw@sisk.pl>2012-04-29 22:53:22 +0200
committerRafael J. Wysocki <rjw@sisk.pl>2012-05-01 21:25:38 +0200
commit7483b4a4d9abf9dcf1ffe6e805ead2847ec3264e (patch)
treed03af746dc3be6480580ec569e0c2d708031f0bd /kernel/power/power.h
parent6791e36c4a40e8930e08669e60077eea6770c429 (diff)
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PM / Sleep: Implement opportunistic sleep, v2
Introduce a mechanism by which the kernel can trigger global transitions to a sleep state chosen by user space if there are no active wakeup sources. It consists of a new sysfs attribute, /sys/power/autosleep, that can be written one of the strings returned by reads from /sys/power/state, an ordered workqueue and a work item carrying out the "suspend" operations. If a string representing the system's sleep state is written to /sys/power/autosleep, the work item triggering transitions to that state is queued up and it requeues itself after every execution until user space writes "off" to /sys/power/autosleep. That work item enables the detection of wakeup events using the functions already defined in drivers/base/power/wakeup.c (with one small modification) and calls either pm_suspend(), or hibernate() to put the system into a sleep state. If a wakeup event is reported while the transition is in progress, it will abort the transition and the "system suspend" work item will be queued up again. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'kernel/power/power.h')
-rw-r--r--kernel/power/power.h18
1 files changed, 18 insertions, 0 deletions
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 98f3622d7407..4cf80fa115d9 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -264,3 +264,21 @@ static inline void suspend_thaw_processes(void)
{
}
#endif
+
+#ifdef CONFIG_PM_AUTOSLEEP
+
+/* kernel/power/autosleep.c */
+extern int pm_autosleep_init(void);
+extern int pm_autosleep_lock(void);
+extern void pm_autosleep_unlock(void);
+extern suspend_state_t pm_autosleep_state(void);
+extern int pm_autosleep_set_state(suspend_state_t state);
+
+#else /* !CONFIG_PM_AUTOSLEEP */
+
+static inline int pm_autosleep_init(void) { return 0; }
+static inline int pm_autosleep_lock(void) { return 0; }
+static inline void pm_autosleep_unlock(void) {}
+static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
+
+#endif /* !CONFIG_PM_AUTOSLEEP */