Implementation of Function-Specific Interfaces
A typical audio adapter card contains a collection of audio hardware functions, which the adapter driver can expose to the WDM audio system through a corresponding collection of IMiniportXxx interfaces. All IMiniportXxx interfaces inherit from IMiniport. Each type of miniport interface--wave, MIDI, topology, and so on--encapsulates a miniport driver for controlling a particular type of audio function on an adapter card. A driver can also expose several instances of the same miniport interface to represent multiple instances of the same (or similar) hardware functions.
For more information, see Miniport Interfaces.