A serializable object, formed by a device driver and containing
characteristics (device state) of the device, is held by a device driver
and made known to a data processing system's power manager. The power
manager provides a device driver independent mechanism for saving device
state by retrieving each device driver's object containing device state
and storing the object in a location that provides for efficient and quick
retrieval. The power manager, being aware of power levels for all devices
on the system, may determine where, how and when to store objects
retrieved from the device drivers for most efficient retrieval. Upon
receiving an interrupt indicating the system should power up, the
serializable objects are retrieved by the power manager and restored to
each device driver.