[Applies to UMDF 1.x only]
The OnReleaseHardware method notifies a driver to perform operations that are necessary when the specified hardware is no longer accessible.
- pWdfDevice [in]
A pointer to the IWDFDevice interface for the device object of the device that is no longer accessible.
OnReleaseHardware returns S_OK if the operation succeeds. Otherwise, this method returns one of the error codes that are defined in Winerror.h. Do not return HRESULT_FROM_NT(STATUS_NOT_SUPPORTED).
This method must use the HRESULT_FROM_NT macro to return a specific HRESULT value to return status to a kernel-mode client. For more information, see Supporting Kernel-mode Clients.
The OnReleaseHardware method must free resources that were allocated during the call to the driver's IPnpCallbackHardware::OnPrepareHardware method whether OnPrepareHardware succeeded or failed. Therefore, OnReleaseHardware must be able to handle the cleanup of partial resources.
For more information, see Finding and Mapping Hardware Resources in a UMDF Driver.