Suspend: Invoke suspend notifications after console switch

In order to fix APM emulation it is necessary to enable apm-emulation
notifications for suspends triggered in various ways via the suspend
notifiers.  However, this will cause the systems using APM emulation
to lock up between X being needed to switch away from the VT and X
already waiting for resume in the APM ioctl.

This patch moves the console switch (if enabled) before the suspend
notification (and after the resume notification) to avoid this issue.

Signed-off-by: Johannes Berg <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Len Brown <[email protected]>

kernel/power/main.c

@@ -175,12 +175,12 @@ static int suspend_prepare(void)
 	if (!suspend_ops || !suspend_ops->enter)
 		return -EPERM;
 
+	pm_prepare_console();
+
 	error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
 	if (error)
 		goto Finish;
 
-	pm_prepare_console();
-
 	if (suspend_freeze_processes()) {
 		error = -EAGAIN;
 		goto Thaw;
@@ -200,9 +200,9 @@ static int suspend_prepare(void)
 
  Thaw:
 	suspend_thaw_processes();
-	pm_restore_console();
  Finish:
 	pm_notifier_call_chain(PM_POST_SUSPEND);
+	pm_restore_console();
 	return error;
 }
 
@@ -309,8 +309,8 @@ int suspend_devices_and_enter(suspend_state_t state)
 static void suspend_finish(void)
 {
 	suspend_thaw_processes();
-	pm_restore_console();
 	pm_notifier_call_chain(PM_POST_SUSPEND);
+	pm_restore_console();
 }