UnregisterEventCallback routine

The UnregisterEventCallback routine deletes the registration of an event callback that was previously registered by a call to RegisterEventCallback.

The function pointer type for an UnregisterEventCallback routine is defined as:

Syntax


PUNREGISTER_EVENT_CALLBACK UnregisterEventCallback;

NTSTATUS UnregisterEventCallback(
  _In_  PVOID context,
  _In_  UCHAR tag
)
{ ... }

Parameters

context [in]

Specifies the context value from the Context member of the HDAUDIO_BUS_INTERFACE, HDAUDIO_BUS_INTERFACE_V2, or HDAUDIO_BUS_INTERFACE_BDL structure.

tag [in]

Specifies the tag value that was associated with the callback by the preceding call to RegisterEventCallback.

Return value

UnregisterEventCallback returns STATUS_SUCCESS if the call succeeds in changing the DMA engines' states. Otherwise, the routine returns an appropriate error code. The following table shows a possible return status code.

Return codeDescription
STATUS_INVALID_PARAMETER

Indicates that the specified tag is not valid.

 

Remarks

Before calling this routine, the function driver is responsible for programming the codec or codecs to remove the association of the callback with the specified tag.

Requirements

Header

Hdaudio.h (include Hdaudio.h)

IRQL

PASSIVE_LEVEL

See also

HDAUDIO_BUS_INTERFACE
HDAUDIO_BUS_INTERFACE_V2
HDAUDIO_BUS_INTERFACE_BDL
RegisterEventCallback

 

 

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