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4/8/2010

This I/O control requests a change from one device power state to another.

Parameters

pBufIn

[in] Set to a pointer to POWER_RELATIONSHIP. This defines the target device for parent and bus drivers. Otherwise, set to NULL.

dwLenIn

[in] Size of the POWER_RELATIONSHIPstructure.

pBufOut

[in] Set to a pointer to CEDEVICE_POWER_STATE. This is the device state in which to put the device.

[out] Contains a pointer to a CEDEVICE_POWER_STATEstructure representing the adjusted device power state chosen by the driver.

dwLenOut

[out] Size of the CEDEVICE_POWER_STATEparameter.

pdwActualOut

[out] Number of bytes passed back in the pBufOutbuffer.

Return Values

TRUE indicates success. FALSE indicates failure.

Remarks

If the driver does not support the proposed device power state, it should write its adjusted device power state into pBufOut.

Power Manager sends this I/O control only to drivers that support the power management I/O controls.

All drivers that account for power must handle this I/O control.

The backlight driver must have a thread that waits for display interfaces.

The backlight driver model device driver (MDD) does this already, so OEMs should either use the MDD in backlight drivers, or refer to it for implementation details.

Your application should not call this control directly to set the device power. Instead, it should use the SetDevicePowerfunction which goes through the Power Manager.

Requirements

Header pm.h
Windows Embedded CE Windows CE .NET 4.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also