Driver Support for Dynamic Subdevices

The code example in Subdevice Creation shows how to use the PcRegisterSubdevice routine to register a subdevice. The Sysvad sample driver, which is discussed in Sample Audio Drivers, shows how to use the PcRegisterPhysicalConnection routine to register the physical connections between subdevices that are contained in the same audio adapter.

The IUnregisterSubdevice and IUnregisterPhysicalConnection interfaces complement the PcRegisterXxx routines. These interfaces contain methods that the sample driver uses to "unregister" devices that were previously registered by calls to the PcRegisterXxx routines. As mentioned previously, these two interfaces are available in Windows Server 2003 with SP1 and later and Windows XP with SP2, but not in earlier Windows versions.