Merge branch 'fix/asoc' into for-linus

[pandora-kernel.git] / Documentation / ABI / testing / sysfs-power

diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 2875f1f..194ca44 100644 (file)
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -99,9 +99,38 @@ Description:
 
                dmesg -s 1000000 | grep 'hash matches'
 
+               If you do not get any matches (or they appear to be false
+               positives), it is possible that the last PM event point
+               referred to a device created by a loadable kernel module.  In
+               this case cat /sys/power/pm_trace_dev_match (see below) after
+               your system is started up and the kernel modules are loaded.
+
                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_trace_dev_match
+Date:          October 2010
+Contact:       James Hogan <james@albanarts.com>
+Description:
+               The /sys/power/pm_trace_dev_match file contains the name of the
+               device associated with the last PM event point saved in the RTC
+               across reboots when pm_trace has been used.  More precisely it
+               contains the list of current devices (including those
+               registered by loadable kernel modules since boot) which match
+               the device hash in the RTC at boot, with a newline after each
+               one.
+
+               The advantage of this file over the hash matches printed to the
+               kernel log (see /sys/power/pm_trace), is that it includes
+               devices created after boot by loadable kernel modules.
+
+               Due to the small hash size necessary to fit in the RTC, it is
+               possible that more than one device matches the hash, in which
+               case further investigation is required to determine which
+               device is causing the problem.  Note that genuine RTC clock
+               values (such as when pm_trace has not been used), can still
+               match a device and output it's name here.
+
 What:          /sys/power/pm_async
 Date:          January 2009
 Contact:       Rafael J. Wysocki <rjw@sisk.pl>