Hibernation: prepare to enter the low power state
During hibernation we call hibernation_ops->prepare() before creating the image,
but then, before saving it, we cancel the power transition by calling
hibernation_ops->finish(). Thus prior to calling hibernation_ops->enter() we
should let the platform firmware know that we're going to enter the low power
state after all.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 77ac605..885c653 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -205,12 +205,23 @@
int hibernation_platform_enter(void)
{
+ int error;
+
if (hibernation_ops) {
kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK);
- return hibernation_ops->enter();
+ /*
+ * We have cancelled the power transition by running
+ * hibernation_ops->finish() before saving the image, so we
+ * should let the firmware know that we're going to enter the
+ * sleep state after all
+ */
+ error = hibernation_ops->prepare();
+ if (!error)
+ error = hibernation_ops->enter();
} else {
- return -ENOSYS;
+ error = -ENOSYS;
}
+ return error;
}
/**