power management: change /sys/power/disk display

Change /sys/power/disk to display all valid modes as well as the currently
selected one in a fashion known from the LED subsystem.

This changes userspace API, but it is apparently not used much (we asked
some userspace developers)

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt
index 8c5b41bf3f36..fd5192a8fa8a 100644
--- a/Documentation/power/interface.txt
+++ b/Documentation/power/interface.txt
@@ -34,8 +34,12 @@ for 5 seconds, resume devices, unfreeze tasks and enable nonboot CPUs.  Then,
 we are able to look in the log messages and work out, for example, which code
 is being slow and which device drivers are misbehaving.
 
-Reading from this file will display what the mode is currently set
-to. Writing to this file will accept one of
+Reading from this file will display all supported modes and the currently
+selected one in brackets, for example
+
+        [shutdown] reboot test testproc
+
+Writing to this file will accept one of
 
        'platform' (only if the platform supports it)
        'shutdown'