The subsystems or drivers having such needs can register suspend notifiers that
will be called upon the following events by the PM core:
-PM_HIBERNATION_PREPARE The system is going to hibernate or suspend, tasks will
- be frozen immediately.
+PM_HIBERNATION_PREPARE The system is going to hibernate, tasks will be frozen
+ immediately. This is different from PM_SUSPEND_PREPARE
+ below because here we do additional work between notifiers
+ and drivers freezing.
PM_POST_HIBERNATION The system memory state has been restored from a
hibernation image or an error occurred during