device.
External suspend calls should never be allowed to fail in this way,
-only autosuspend calls. The driver can tell them apart by checking
-the PM_EVENT_AUTO bit in the message.event argument to the suspend
-method; this bit will be set for internal PM events (autosuspend) and
-clear for external PM events.
+only autosuspend calls. The driver can tell them apart by applying
+the PMSG_IS_AUTO() macro to the message argument to the suspend
+method; it will return True for internal PM events (autosuspend) and
+False for external PM events.
Mutual exclusion