Handling System Power State Requests
All drivers must be able to respond to system power state requests if the system is to sleep, hibernate, and wake successfully. A driver for a device changes the device power state for the device in response to system power state requests.
If any driver does not support system power management, individual devices can sleep and wake, but the power manager cannot put the system as a whole into a sleeping state.
The following topics cover details of handling system power state requests: