PM: Add a switch for disabling/enabling asynchronous suspend/resume
Add sysfs attribute /sys/power/pm_async allowing the user space to
disable/enable asynchronous suspend/resume of devices.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index dcff4d0..d6a801f 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -101,3 +101,16 @@
CAUTION: Using it will cause your machine's real-time (CMOS)
clock to be set to a random invalid time after a resume.
+
+What: /sys/power/pm_async
+Date: January 2009
+Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Description:
+ The /sys/power/pm_async file controls the switch allowing the
+ user space to enable or disable asynchronous suspend and resume
+ of devices. If enabled, this feature will cause some device
+ drivers' suspend and resume callbacks to be executed in parallel
+ with each other and with the main suspend thread. It is enabled
+ if this file contains "1", which is the default. It may be
+ disabled by writing "0" to this file, in which case all devices
+ will be suspended and resumed synchronously.