KsDereferenceBusObject function

Description

Dereferences the bus Physical Device Object.

Parameters

Header [in]

Points to a header previously allocated by KsAllocateDeviceHeader that also contains the PnP device stack object.

Return value

None.

Remarks

This is used by filters that use the device header to keep track of the corresponding PnP object stack. This is normally called when closing a filter, if required by the bus for the given device. As an example, a software device would require such a call. This call matches a previous call to KsReferenceBusObject when opening the filter instance. The caller must have previously also called KsSetDevicePnpAndBaseObject in order to set the PnP device stack object. This would have been done in the PnP AddDevice function. The function calls the DereferenceDeviceObject method on the previously retrieved interface. The interface itself is released and freed when the device header is freed.