The class driver issues this request to indicate to a stream that it now serves as the master clock for the minidriver.
The minidriver should set one of the following as the status in the SRB:
Indicates successful completion of the command.
Indicates that the function is not supported by the minidriver.
Indicates that a hardware failure occurred.
The class driver sets the CommandData.MasterClockHandle member pointed to by pSrb to the handle for the clock object it creates to represent the master clock. The pSrb pointer points to a HW_STREAM_REQUEST_BLOCK structure.
The minidriver should retain the CommandData.MasterClockHandle field value in the SRB that points to the handle of the master clock.