Driver Access to Hardware

The following table lists all of the event callback functions that the framework device object defines, in alphabetical order. The table shows you the callback functions in which your driver can access the hardware that the callback function's WDFDEVICE handle represents. You can access the hardware because the device is in its working (D0) state.

Event callbacks functionsfor framework device objects	Is hardware accessible?
EvtDeviceArmWakeFromS0	Yes
EvtDeviceArmWakeFromSx	Yes
EvtDeviceArmWakeFromSxWithReason	Yes
EvtDeviceD0Entry	Yes
EvtDeviceD0Exit	Yes
EvtDeviceDisableWakeAtBus	Parent bus might be at D0. The device might be at D0.
EvtDeviceDisarmWakeFromS0	Yes
EvtDeviceDisarmWakeFromSx	Yes
EvtDeviceEject	No
EvtDeviceEnableWakeAtBus	Parent bus is at D0, but the device might not be.
EvtDeviceFileCreate	Maybe
EvtDeviceFilterAddResourceRequirements	No
EvtDeviceFilterRemoveResourceRequirements	No
EvtDevicePrepareHardware	Yes
EvtDeviceRelationsQuery	Yes, but the device might be in a sleeping state.
EvtDeviceReleaseHardware	No
EvtDeviceRemoveAddedResources	Yes, but resources have not been assigned to the device.
EvtDeviceResourceRequirementsQuery	No
EvtDeviceResourcesQuery	No
EvtDeviceSelfManagedIoCleanup	No
EvtDeviceSelfManagedIoFlush	No
EvtDeviceSelfManagedIoInit	Yes
EvtDeviceSelfManagedIoRestart	Yes
EvtDeviceSelfManagedIoSuspend	No, if device has been surprise-removed; otherwise, yes.
EvtDeviceSetLock	No
EvtDeviceSurpriseRemoval	No
EvtDeviceUsageNotification	Yes
EvtDeviceWakeFromS0Triggered	Yes
EvtDeviceWakeFromSxTriggered	Yes
EvtDeviceWdmIrpPreprocess	Depends on the IRP.
EvtDevicePnpStateChange	Depends on the state.
EvtDevicePowerPolicyStateChange	Depends on the state.
EvtDevicePowerStateChange	Depends on the state.