[PATCH] introduce .valid callback for pm_ops

Add pm_ops.valid callback, so only the available pm states show in
/sys/power/state.  And this also makes an earlier states error report at
enter_state before we do actual suspend/resume.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Acked-by: Pavel Machek<pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/pm.h b/include/linux/pm.h
index c61d5de837ef..1514098d156d 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -170,6 +170,7 @@ typedef int __bitwise suspend_disk_method_t;
 
 struct pm_ops {
         suspend_disk_method_t pm_disk_mode;
+        int (*valid)(suspend_state_t state);
         int (*prepare)(suspend_state_t state);
         int (*enter)(suspend_state_t state);
         int (*finish)(suspend_state_t state);