3.3.4 Library Interface

This section describes the Application Programming Interface (API) functions of the USB Audio v1.0 Host Client Driver Library.

Refer to each section for a detailed description.

Audio Device Access Functions

Name Description
USB_HOST_AUDIO_V1_AttachEventHandlerSet Sets an attach/detach event handler.
USB_HOST_AUDIO_V1_ControlEntityGetFirst Retrieves the handle to the first audio control entity.
USB_HOST_AUDIO_V1_ControlEntityGetNext Retrieves the handle to the next audio control entity.
USB_HOST_AUDIO_V1_DeviceObjHandleGet Returns the device object handle for this Audio v1.0 Device.
USB_HOST_AUDIO_V1_EntityObjectGet Retrieves the entity object for the entity ID.
USB_HOST_AUDIO_V1_EntityRequestCallbackSet Registers an audio entity request callback function with the Audio v1.0 Client Driver.
USB_HOST_AUDIO_V1_EntityTypeGet Returns the entity type of the audio control entity.
USB_HOST_AUDIO_V1_FeatureUnitChannelMuteExists Returns "true" if mute control exists for the specified channel of the feature unit.
USB_HOST_AUDIO_V1_FeatureUnitChannelMuteGet Schedules a get mute control request to the specified channel.
USB_HOST_AUDIO_V1_FeatureUnitChannelMuteSet Schedules a set mute control request to the specified channel.
USB_HOST_AUDIO_V1_FeatureUnitChannelNumbersGet Returns the number of channels.
USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeExists Returns "true" if volume control exists for the specified channel of the feature unit.
USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeGet Schedules a get current volume control request to the specified channel.
USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeRangeGet Schedules a control request to the Audio Device feature unit to get the range supported by the volume control on the specified channel.
USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeSet Schedules a set current volume control request to the specified channel.
USB_HOST_AUDIO_V1_FeatureUnitIDGet Returns ID of the Feature Unit.
USB_HOST_AUDIO_V1_FeatureUnitSourceIDGet Returns the ID of the unit or terminal to which this feature unit is connected.
USB_HOST_AUDIO_V1_TerminalAssociationGet Returns the associated terminal ID of the audio control terminal.
USB_HOST_AUDIO_V1_TerminalIDGet Returns the terminal ID of the audio control entity.
USB_HOST_AUDIO_V1_TerminalInputChannelNumbersGet Returns the number of logical output channels in the terminal's output audio channel cluster.
USB_HOST_AUDIO_V1_TerminalSourceIDGet Returns the ID of the unit or terminal to which this terminal is connected.
USB_HOST_AUDIO_V1_TerminalTypeGet Returns the terminal type of the audio control entity.

Audio Stream Access Functions

Name Description
USB_HOST_AUDIO_V1_StreamClose Closes the audio stream.
USB_HOST_AUDIO_V1_StreamEventHandlerSet Registers an event handler with the Audio v1.0 Client Driver stream.
USB_HOST_AUDIO_V1_StreamingInterfaceBitResolutionGet Returns the bit resolution of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceChannelNumbersGet Returns the number of channels of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceDirectionGet Returns the direction of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceFormatTagGet Returns the format tag of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceGetFirst Gets the first streaming interface object from the attached Audio Device.
USB_HOST_AUDIO_V1_StreamingInterfaceGetNext Gets the next streaming interface object from the attached Audio Device.
USB_HOST_AUDIO_V1_StreamingInterfaceSamplingFrequenciesGet Returns the sampling frequencies supported by the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceSamplingFrequencyTypeGet Returns the sampling frequency type of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceSet Schedules a SET_INTERFACE request to the specified audio stream.
USB_HOST_AUDIO_V1_StreamingInterfaceSettingGetFirst Gets the first streaming interface setting object within an audio streaming interface.
USB_HOST_AUDIO_V1_StreamingInterfaceSettingGetNext Gets the next streaming interface setting object within an audio streaming interface.
USB_HOST_AUDIO_V1_StreamingInterfaceSubFrameSizeGet Returns the sub-frame size of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamingInterfaceTerminalLinkGet Returns the terminal link of the specified streaming interface setting.
USB_HOST_AUDIO_V1_StreamOpen Opens the specified audio stream.
USB_HOST_AUDIO_V1_StreamRead Schedules an audio stream read request for the specified audio stream.
USB_HOST_AUDIO_V1_StreamSamplingFrequencyGet Schedules an audio stream get sampling rate request for the specified audio stream.
USB_HOST_AUDIO_V1_StreamSamplingFrequencySet Schedules an audio stream set sampling rate request for the specified audio stream.
USB_HOST_AUDIO_V1_StreamWrite Schedules an audio stream write request for the specified audio stream.

Other Functions

Name Description
USB_HOST_AUDIO_V1_FeatureUnitChannelVolumeSubRangeNumbersGet Schedules a control request to an Audio Device feature unit to get the number of sub-ranges supported by the volume control on the specified channel.
USB_HOST_AUDIO_V1_TerminalInputChannelConfigGet Returns a structure that describes the spatial location of the logical channels of in the terminal's output audio channel cluster.

Data Types and Constants

Name Description
USB_HOST_AUDIO_V1_ATTACH_EVENT_HANDLER USB Host Audio v1.0 Client Driver attach event handler function pointer type.
USB_HOST_AUDIO_V1_CONTROL_ENTITY_OBJ Defines the type of the Audio v1.0 Host control entity object.
USB_HOST_AUDIO_V1_ENTITY_REQUEST_CALLBACK USB Host Audio v1.0 class driver control transfer complete callback function pointer type.
USB_HOST_AUDIO_V1_EVENT Identifies the possible events that the Audio v1.0 Class Driver attach event handler can generate.
USB_HOST_AUDIO_V1_OBJ Defines the type of the Audio v1.0 Host client object.
USB_HOST_AUDIO_V1_REQUEST_HANDLE USB Host Audio v1.0 Client Driver request handle.
USB_HOST_AUDIO_V1_RESULT USB Host Audio v1.0 Class Driver result enumeration.
USB_HOST_AUDIO_V1_STREAM_DIRECTION USB Host Audio v1.0 Class Driver stream direction.
USB_HOST_AUDIO_V1_STREAM_EVENT Identifies the possible events that the Audio v1.0 Stream can generate.
USB_HOST_AUDIO_V1_STREAM_EVENT_HANDLER USB Host Audio v1.0 Class Driver stream event handler function pointer type.
USB_HOST_AUDIO_V1_STREAM_EVENT_INTERFACE_SET_COMPLETE_DATA USB Host Audio v1.0 class stream control event data.
USB_HOST_AUDIO_V1_STREAM_EVENT_READ_COMPLETE_DATA USB Host Audio v1.0 class stream data transfer event data.
USB_HOST_AUDIO_V1_STREAM_EVENT_RESPONSE Returns the type of the USB Host Audio v1.0 stream event handler.
USB_HOST_AUDIO_V1_STREAM_EVENT_SAMPLING_RATE_SET_COMPLETE_DATA USB Host Audio v1.0 class stream control event data.
USB_HOST_AUDIO_V1_STREAM_EVENT_WRITE_COMPLETE_DATA USB Host Audio v1.0 class stream data transfer event data.
USB_HOST_AUDIO_V1_STREAM_HANDLE Defines the type of the Audio v1.0 Host stream handle.
USB_HOST_AUDIO_V1_STREAM_TRANSFER_HANDLE USB Host Audio v1.0 Class Driver stream data transfer handle.
USB_HOST_AUDIO_V1_STREAMING_INTERFACE_OBJ Defines the type of the Audio v1.0 Host streaming interface object.
USB_HOST_AUDIO_V1_STREAMING_INTERFACE_SETTING_OBJ Defines the type of the Audio v1.0 Host streaming interface setting object.
USB_HOST_AUDIO_V1_INTERFACE USB HOST Audio v1.0 Client Driver interface.
USB_HOST_AUDIO_V1_REQUEST_HANDLE_INVALID USB Host Audio v1.0 Client Driver invalid request handle.
USB_HOST_AUDIO_V1_SAMPLING_FREQUENCIES_NUMBER This structure defines USB Host audio stream information structure.
USB_HOST_AUDIO_V1_STREAM_HANDLE_INVALID Defines Audio v1.0 Host stream invalid handle.
USB_HOST_AUDIO_V1_STREAM_TRANSFER_HANDLE_INVALID USB Host Audio v1.0 Class Driver invalid stream data transfer handle.
USB_HOST_AUDIO_V1_STREAM_EVENT_SAMPLING_RATE_GET_COMPLETE_DATA USB Host Audio v1.0 class stream control event data.