diff options
authorJohannes Berg <johannes@sipsolutions.net>2007-04-30 15:09:55 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-04-30 16:40:40 -0700
commit9684e51cd157607f0727c1550e7df6e31de40808 (patch)
parentpower management: implement pm_ops.valid for everybody (diff)
power management: force pm_ops.valid callback to be assigned
This patch changes the docs and behaviour from "all states valid" to "no states valid" if no .valid callback is assigned. Users of pm_ops that only need mem sleep can assign pm_valid_only_mem without any overhead, others will require more elaborate callbacks. Now that all users of pm_ops have a .valid callback this is a safe thing to do and prevents things from getting messy again as they were before. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Pavel Machek <pavel@ucw.cz> Looks-okay-to: Rafael J. Wysocki <rjw@sisk.pl> Cc: <linux-pm@lists.linux-foundation.org> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 files changed, 8 insertions, 8 deletions
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 6035209cf31e..7a516690dcb3 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -125,12 +125,12 @@ typedef int __bitwise suspend_disk_method_t;
* struct pm_ops - Callbacks for managing platform dependent suspend states.
* @valid: Callback to determine whether the given state can be entered.
- * always valid and never passed to this call.
- * If not assigned, all suspend states are advertised as valid
- * in /sys/power/state (but can still be rejected by prepare or enter.)
- * Since new states can be added for other platforms, you should
- * assign this callback. There is a %pm_valid_only_mem function
- * available if you only implemented mem sleep.
+ * always valid and never passed to this call. If not assigned,
+ * no suspend states are valid.
+ * Valid states are advertised in /sys/power/state but can still
+ * be rejected by prepare or enter if the conditions aren't right.
+ * There is a %pm_valid_only_mem function available that can be assigned
+ * to this if you only implement mem sleep.
* @prepare: Prepare the platform for the given suspend state. Can return a
* negative error code if necessary.
diff --git a/kernel/power/main.c b/kernel/power/main.c
index f94f4e20115a..72419a3b1beb 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -198,8 +198,8 @@ static inline int valid_state(suspend_state_t state)
/* all other states need lowlevel support and need to be
* valid to the lowlevel implementation, no valid callback
- * implies that all are valid. */
- if (!pm_ops || (pm_ops->valid && !pm_ops->valid(state)))
+ * implies that none are valid. */
+ if (!pm_ops || !pm_ops->valid || !pm_ops->valid(state))
return 0;
return 1;