Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux...

[~andy/linux] / Documentation / power / basic-pm-debugging.txt

diff --git a/Documentation/power/basic-pm-debugging.txt b/Documentation/power/basic-pm-debugging.txt
index 05a7fe76232de4280b8b4ea4e6925a1b124ec780..40a4c65f380a10479a7a805d58310be97b1a2ee1 100644 (file)
--- a/Documentation/power/basic-pm-debugging.txt
+++ b/Documentation/power/basic-pm-debugging.txt
@@ -201,3 +201,27 @@ case, you may be able to search for failing drivers by following the procedure
 analogous to the one described in section 1.  If you find some failing drivers,
 you will have to unload them every time before an STR transition (ie. before
 you run s2ram), and please report the problems with them.
+
+There is a debugfs entry which shows the suspend to RAM statistics. Here is an
+example of its output.
+       # mount -t debugfs none /sys/kernel/debug
+       # cat /sys/kernel/debug/suspend_stats
+       success: 20
+       fail: 5
+       failed_freeze: 0
+       failed_prepare: 0
+       failed_suspend: 5
+       failed_suspend_noirq: 0
+       failed_resume: 0
+       failed_resume_noirq: 0
+       failures:
+         last_failed_dev:      alarm
+                               adc
+         last_failed_errno:    -16
+                               -16
+         last_failed_step:     suspend
+                               suspend
+Field success means the success number of suspend to RAM, and field fail means
+the failure number. Others are the failure number of different steps of suspend
+to RAM. suspend_stats just lists the last 2 failed devices, error number and
+failed step of suspend.