USB Audio Device class for audio streaming over USB. More...

#include <USBAudioDeviceBase.h>

Inheritance diagram for USBAudioDeviceBase:

Public Member Functions
	USBAudioDeviceBase ()
	Default Constructor.

	USBAudioDeviceBase (USBAudioConfig cfg)
	Constructor which provides configuration at construction time.

virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.

virtual AudioInfo	audioInfo () override
	provides the actual input AudioInfo

virtual AudioInfo	audioInfoOut ()

uint16_t	audioPacketSize () const
	One isochronous USB packet size in bytes (same formula as the descriptor builder).

int	available () override
	Bytes of received audio waiting in the RX buffer.

int	availableForWrite () override
	Bytes of free space in the TX buffer.

bool	begin ()
	(Re-)start the USB audio device with the current config.

bool	begin (const USBAudioConfig &cfg)
	Apply a config and start the USB audio device.

virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.

USBAudioConfig	defaultConfig (RxTxMode mode=RXTX_MODE)
	Returns a default configuration pre-filled for the requested direction (RX_MODE, TX_MODE, or RXTX_MODE). Use TX if you write and rx if you want to read audio data. RXTX is for full duplex.

void	end ()
	Stop audio streaming and clear FIFOs. Does not disconnect USB.

virtual void	flush () override

uint8_t	getAudioCount () const
	Returns the number of audio functions (always 1).

usbd_class_driver_t const *	getClassDriver (uint8_t *count)
	Get the USB device class driver for TinyUSB integration.

uint16_t	getDescriptor (uint8_t *desc)
	Returns the audio-function descriptor block for use in tud_descriptor_configuration_cb().

uint32_t	getRxTotalBytes () const
	Total bytes received from host via OUT endpoint.

uint32_t	getRxXferCount () const
	Number of times audiod_xfer_cb fired for the OUT endpoint.

uint8_t	getTxBytesPerSample () const
	TX bytes per sample parsed from the descriptor.

uint8_t	getTxChannels () const
	TX channel count parsed from the descriptor.

uint32_t	getTxFifoReadTotal () const

uint16_t	getTxFrameBytesLast () const

uint8_t	getTxInterval () const
	TX isochronous interval (bInterval) parsed from the descriptor.

uint32_t	getTxSampleRate () const
	TX sample rate parsed from the descriptor (must be non-zero for flow control).

uint32_t	getTxXferCount () const
	Number of times audiod_xfer_cb fired for the IN endpoint.

uint32_t	getTxXferredLast () const

bool	isEpInEnabled () const
	Returns true if the IN endpoint is enabled.

bool	isEpInFlowControlEnabled () const
	Returns true if IN endpoint flow control is enabled. When on, the per-frame isochronous packet size is varied so non-integer sample-per- frame rates (e.g. 44100 Hz) are delivered at the exact average rate.

bool	isEpOutEnabled () const
	Returns true if the OUT endpoint is enabled.

bool	isFeedbackEpEnabled () const
	Returns true if the feedback endpoint is enabled. Only meaningful in pure RX (OUT-only) mode: with an IN endpoint present the host uses the TX stream as implicit feedback instead.

bool	isFifoMutexEnabled () const
	Returns true if FIFO mutex is enabled.

bool	isInterruptEpEnabled () const
	Returns true if the interrupt endpoint is enabled.

bool	isMute (uint8_t channel=0) const
	Returns the current mute state for the given channel.

bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.

bool	isStreamingActive () const
	Returns true if either IN or OUT streaming endpoint is open.

bool	isStreamingActiveRx () const
	Returns true if the host has opened the OUT (playback) stream.

bool	isStreamingActiveTx () const
	Returns true if the host has opened the IN (capture) stream.

bool	isTxXferArmed () const
	True if the initial isochronous IN transfer was armed successfully.

bool	mounted () const
	Returns true if the device is mounted by the USB host.

uint8_t	numInterfaces () const
	Total number of USB interfaces claimed by the audio function (1 AC + 1 or 2 AS), for use in the bNumInterfaces field of the configuration descriptor.

	operator bool () override
	Returns true when begin() has been called and the USB host has mounted the device.

size_t	readBytes (uint8_t *buffer, size_t bufsize)
	Receive audio data from the host (host → device, speaker/playback).

virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.

virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.

void	setAudioFeedbackFormatCorrectionCallback (std::function< bool(USBAudioDeviceBase *, uint8_t)> cb)
	Register a callback for audio feedback format correction events.

void	setAudioFeedbackParamsCallback (std::function< void(USBAudioDeviceBase , uint8_t, uint8_t, audio_feedback_params_t )> cb)
	Register a callback for audio feedback parameter events.

void	setAudioInfo (AudioInfo info) override
	Change the sample rate and notify the host.

void	setFbDoneCallback (std::function< void(USBAudioDeviceBase *, uint8_t)> cb)
	Register a callback for feedback done events.

void	setGetReqEpCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const )> cb)
	Register a callback for GET requests on an endpoint.

void	setGetReqItfCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const )> cb)
	Register a callback for GET requests on the interface.

void	setIntDoneCallback (std::function< void(USBAudioDeviceBase *, uint8_t)> cb)
	Register a callback for interrupt done events.

void	setItfCloseEpCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const )> cb)
	Register a callback for interface close endpoint events.

bool	setMute (bool m, uint8_t channel=0)
	Set the mute state for a channel and notify the host.

void	setMuteCallback (std::function< void(bool, uint8_t)> cb)
	Register a callback invoked when the host (or device) changes the mute state.

void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)

void	setReqEntityCallback (std::function< bool(USBAudioDeviceBase *, uint8_t)> cb)
	Register a callback for entity requests.

void	setReqEntityCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const , uint8_t *)> cb)
	Register a callback for entity set requests.

void	setReqEpCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const , uint8_t *)> cb)
	Register a callback for endpoint set requests.

void	setReqItfCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const , uint8_t *)> cb)
	Register a callback for interface set requests.

void	setRxDoneCallback (std::function< bool(USBAudioDeviceBase , uint8_t, audiod_function_t , uint16_t)> cb)
	Register a callback for RX done events.

void	setSampleRateCallback (std::function< void(uint32_t)> cb)
	Register a callback invoked when the host (or device) changes the sample rate.

void	setStreamingStateCallback (std::function< void(bool, bool)> cb)
	Register a callback invoked when the streaming state changes. Fires when the host opens or closes a streaming interface (SET_INTERFACE alt=1 / alt=0).

void	setTudAudioSetItfCallback (std::function< bool(USBAudioDeviceBase , uint8_t, tusb_control_request_t const )> cb)
	Register a callback for interface set requests.

void	setTxDoneCallback (std::function< bool(USBAudioDeviceBase , uint8_t, audiod_function_t )> cb)
	Register a callback for TX done events.

bool	setVolume (float vol, uint8_t channel)
	Set the volume for a channel and notify the host.

bool	setVolume (float volume) override
	sets the volume for the master channel (channel 0)

void	setVolumeCallback (std::function< void(float, uint8_t)> cb)
	Register a callback invoked when the host (or device) changes the volume.

void	setWriteBufferSize (int size)

float	volume () override
	gets the volume for the master channel (channel 0)

float	volume (uint8_t channel)
	Returns the current volume for the given channel.

size_t	write (const uint8_t *data, size_t len)
	Send audio data to the host (device → host, microphone/capture). Silently discards data when the host has not opened the capture device (alt=0) so StreamCopy doesn't report write errors before recording.

virtual size_t	write (uint8_t ch) override

virtual void	writeSilence (size_t len)
	Writes len bytes of silence (=0).

Static Public Member Functions
static USBAudioDeviceBase &	activeInstance ()
	Returns the most-recently-constructed instance (base or subclass).

Protected Member Functions
bool	activateEndpoint (uint8_t rhport, tusb_desc_endpoint_t const *desc_ep, uint8_t dir=TUSB_DIR_IN)

void	alloc_mutex ()

bool	audiod_calc_tx_packet_sz (audiod_function_t *audio)

bool	audiod_control_complete (uint8_t rhport, tusb_control_request_t const *p_request)

bool	audiod_control_request (uint8_t rhport, tusb_control_request_t const *p_request)

bool	audiod_control_xfer_cb (uint8_t rhport, uint8_t stage, tusb_control_request_t const *request)

bool	audiod_deinit (void)

bool	audiod_fb_send (audiod_function_t *audio)

bool	audiod_get_AS_interface_index (uint8_t itf, audiod_function_t audio, uint8_t idxItf, uint8_t const **pp_desc_int)

bool	audiod_get_AS_interface_index_global (uint8_t itf, uint8_t func_id, uint8_t idxItf, uint8_t const **pp_desc_int)

bool	audiod_get_interface (uint8_t rhport, tusb_control_request_t const *p_request)

void	audiod_init (void)

uint16_t	audiod_open (uint8_t rhport, tusb_desc_interface_t const *itf_desc, uint16_t max_len)

void	audiod_parse_flow_control_params (audiod_function_t audio, uint8_t const p_desc)

void	audiod_reset (uint8_t rhport)

bool	audiod_set_fb_params_freq (audiod_function_t *audio, uint32_t sample_freq, uint32_t mclk_freq)

bool	audiod_set_interface (uint8_t rhport, tusb_control_request_t const *p_request)

TU_ATTR_FAST_FUNC void	audiod_sof_isr (uint8_t rhport, uint32_t frame_count)

uint16_t	audiod_tx_packet_size_fc (audiod_function_t *audio)

bool	audiod_verify_entity_exists (uint8_t itf, uint8_t entityID, uint8_t *func_id)

bool	audiod_verify_ep_exists (uint8_t ep, uint8_t *func_id)

bool	audiod_verify_itf_exists (uint8_t itf, uint8_t *func_id)

bool	audiod_xfer_cb (uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes)
	TODO refactor control request handling to separate function and reduce nesting.

virtual bool	beginUSB ()=0
	Override in platform subclasses to register descriptors and start the USB host-controller stack (e.g. USB.begin() on ESP32). Called at the end of begin(cfg, info). The base no-op is correct for RP2040 where TinyUSB is started by the system before setup().

virtual BaseBuffer< uint8_t > &	bufferRx ()=0
	Returns the RX audio buffer. Must be overridden by subclasses.

virtual BaseBuffer< uint8_t > &	bufferTx ()=0
	Returns the TX audio buffer. Must be overridden by subclasses.

void	closeEpIn (uint8_t rhport, audiod_function_t audio, uint8_t itf, tusb_control_request_t const p_request)

void	closeEpOut (uint8_t rhport, audiod_function_t audio, uint8_t itf, tusb_control_request_t const p_request)

bool	configChanged (const USBAudioConfig &n)

uint16_t	fifoSize () const

uint16_t	getCtrlBufSz (uint8_t fn) const

uint16_t	getDescLen (uint8_t fn) const

uint16_t	getEpInSwBufSz (uint8_t fn) const

uint16_t	getEpOutSwBufSz (uint8_t fn) const

float	getVolumeExt (uint8_t channel) const
	Returns the effective volume for a per-channel index (1-based). Combines master volume (index 0) with per-channel volume and mute.

bool	handleClockSourceGet (uint8_t rhport, tusb_control_request_t const p_request, uint8_t cb)

bool	handleEndpointRequest (uint8_t rhport, tusb_control_request_t const *p_request)

bool	handleEntityRequest (uint8_t rhport, tusb_control_request_t const *p_request, uint8_t entityID)

bool	handleFeatureUnitGet (uint8_t rhport, tusb_control_request_t const p_request, uint8_t cb)

bool	handleInterfaceRequest (uint8_t rhport, tusb_control_request_t const *p_request)

bool	isFeatureUnit (uint8_t id) const
	Returns true if the given entity ID is a Feature Unit (FU1 or FU2).

bool	isUseLinearBufferRx () const

bool	isUseLinearBufferTx () const

virtual int	not_supported (int out, const char *msg="")

void	notifyAudioChange (AudioInfo info)

void	notifyStreamingState ()

bool	openEndpointsForAltSetting (uint8_t rhport, audiod_function_t *audio, uint8_t func_id, uint8_t itf, uint8_t alt)

void	openEpFeedback (audiod_function_t audio, tusb_desc_endpoint_t const desc_ep)

void	openEpIn (uint8_t rhport, audiod_function_t audio, uint8_t itf, tusb_desc_endpoint_t const desc_ep, uint8_t const *p_desc_for_params)

void	openEpOut (uint8_t rhport, audiod_function_t audio, uint8_t itf, tusb_desc_endpoint_t const desc_ep)

uint16_t	packetSize () const

template<typename T >
void	processVolume (T *data, size_t sample_count)

void	processVolume (uint8_t *data, size_t len)
	Process audio data for volume control.

void	refillReadBuffer ()
	Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read()

virtual void	resizeBuffers ()=0
	Resize the platform audio buffers. Both platforms use NBuffer-style block pools: block size = max USB packet, block count = fifo_packets. ESP32: SynchronizedNBufferRTOS (FreeRTOS queues, cross-core safe). RP2040: NBuffer (single-core, no synchronization needed).

void	sendInterruptNotification (uint8_t ctrlSel, uint8_t channel, uint8_t entityID)
	Send a UAC2 status/change notification via the AC interrupt EP.

virtual void	serviceTinyUSB ()
	Process pending USB events on platforms where the application drives the stack (RP2040, STM32, ...). Skipped when a dedicated FreeRTOS task already calls tud_task() continuously (see usb_task_active_) - tud_task() is not re-entrant; calling it from two contexts concurrently corrupts TinyUSB's internal event queue and causes random hangs.

void	setConfig (const USBAudioConfig &cfg)
	Set the USB audio configuration (use begin(cfg) instead).

void	setSampleRate (uint32_t rate)
	Device-initiated sample rate change.

void	setupFeedback (audiod_function_t *audio, uint8_t func_id, uint8_t alt)

void	tud_audio_feedback_interval_isr (uint8_t func_id, uint32_t, uint8_t frame_shift)

uint16_t	tud_audio_n_available (uint8_t func_id)

uint16_t	tud_audio_n_read (uint8_t func_id, void *buffer, uint16_t bufsize)

uint16_t	tud_audio_n_write (uint8_t func_id, const void *data, uint16_t len)

Static Protected Member Functions
static int16_t	floatToUac2 (float vol)
	Convert linear volume (0.0–1.0) to UAC2 int16 (1/256 dB). Linear mapping: 0.0 → -100 dB (min), 1.0 → 0 dB (max).

static constexpr size_t	getResetSize ()

static bool	isValidBitsPerSample (uint8_t bps)

static float	uac2ToFloat (int16_t v)
	Convert UAC2 int16 (1/256 dB) to linear volume (0.0–1.0). Linear mapping within the -100..0 dB range reported by GET_RANGE.

Protected Attributes
int	_timeout = 10

USBAudioConfig	active_config_

std::vector< audiod_function_t >	audiod_fct_

USBAudioConfig	config_

std::vector< uint16_t >	ctrl_buf_sz_

std::vector< uint16_t >	desc_len_

USBAudio2DescriptorBuilder	descr_builder {config_}

std::vector< uint16_t >	ep_in_sw_buf_sz_

std::vector< osal_mutex_def_t >	ep_out_ff_mutex_rd_

std::vector< uint16_t >	ep_out_sw_buf_sz_

std::function< void(USBAudioDeviceBase *, uint8_t func_id)>	fb_done_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const )>	get_req_ep_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const )>	get_req_itf_cb_

AudioInfo	info

std::function< void(USBAudioDeviceBase *, uint8_t rhport)>	int_done_cb_

uint8_t	int_notify_buf_ [6] = {}

bool	is_active_ = false

bool	is_notify_active = true

bool	is_started_ = false

std::vector< bool >	mute_

std::function< void(bool, uint8_t)>	mute_cb_

Vector< AudioInfoSupport * >	notify_vector

std::function< bool(USBAudioDeviceBase *, uint8_t func_id)>	req_entity_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, audiod_function_t , uint16_t xferred_bytes)>	rx_done_cb_

volatile uint32_t	rx_total_bytes_ = 0

std::function< void(uint32_t)>	sample_rate_cb_

std::function< void(bool, bool)>	streaming_state_cb_

RingBuffer< uint8_t >	tmp_in {0}

RingBuffer< uint8_t >	tmp_out {0}

std::function< bool(USBAudioDeviceBase *, uint8_t func_id)>	tud_audio_feedback_format_correction_cb_

std::function< void(USBAudioDeviceBase , uint8_t func_id, uint8_t alt_itf, audio_feedback_params_t feedback_param)>	tud_audio_feedback_params_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const p_request)>	tud_audio_set_itf_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const p_request)>	tud_audio_set_itf_close_EP_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const p_request, uint8_t *pBuff)>	tud_audio_set_req_entity_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const p_request, uint8_t *pBuff)>	tud_audio_set_req_ep_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, tusb_control_request_t const p_request, uint8_t *pBuff)>	tud_audio_set_req_itf_cb_

std::function< bool(USBAudioDeviceBase , uint8_t rhport, audiod_function_t )>	tx_done_cb_

volatile uint32_t	tx_fifo_read_total_ = 0

volatile uint16_t	tx_frame_bytes_last_ = 0

bool	tx_xfer_armed_ = false

volatile uint32_t	tx_xferred_last_ = 0

bool	usb_task_active_ = false

std::vector< float >	volume_

std::function< void(float, uint8_t)>	volume_cb_

float	volume_value = 1.0f

int	write_buffer_size = MAX_SINGLE_CHARS

volatile uint32_t	xfer_cb_rx_count_ = 0

volatile uint32_t	xfer_cb_tx_count_ = 0

Static Protected Attributes
static constexpr int16_t	kVolumeMinDb256 = -25600
	Convert AudioTools volume (0.0–1.0) to UAC2 int16 (1/256 dB). 0.0 maps to 0x8000 (silence), 1.0 maps to 0 (0 dB).

static USBAudioDeviceBase *	s_active_ = nullptr

Detailed Description

USB Audio Device class for audio streaming over USB.

This class implements a USB audio device, providing configuration, descriptor management, endpoint setup, and control request handling for audio streaming over USB. It supports multiple audio formats, feedback methods, and endpoint configurations, and is designed for use with TinyUSB or native USB on supported MCUs.

Author: Phil Schatzmann

Copyright: GPLv3

Constructor & Destructor Documentation

◆ USBAudioDeviceBase() [1/2]

USBAudioDeviceBase ( )

inline

Default Constructor.

◆ USBAudioDeviceBase() [2/2]

USBAudioDeviceBase ( USBAudioConfig cfg )

inline

Constructor which provides configuration at construction time.

Member Function Documentation

◆ activateEndpoint()

bool activateEndpoint	(	uint8_t	rhport,
		tusb_desc_endpoint_t const *	desc_ep,
		uint8_t	dir = `TUSB_DIR_IN`
	)

inlineprotected

◆ activeInstance()

static USBAudioDeviceBase & activeInstance ( )

inlinestatic

Returns the most-recently-constructed instance (base or subclass).

Set in the constructor via s_active_, so usbd_app_driver_get_cb() and the static process() trampoline can reach the right object without a singleton.

◆ addNotifyAudioChange()

virtual void addNotifyAudioChange ( AudioInfoSupport & bi )

inlinevirtualinherited

Adds target to be notified about audio changes.

Reimplemented in CodecNOP, EncodedAudioOutput, EncodedAudioStream, AACDecoderFDK, DecoderBasic, CodecChain, MP3DecoderHelix, MP3DecoderMAD, OggContainerDecoder, RTSPClient< TcpClient, UdpSocket >, Pipeline, and Pipeline::ModifyingStreamAdapter.

◆ alloc_mutex()

void alloc_mutex ( )

inlineprotected

◆ audiod_calc_tx_packet_sz()

bool audiod_calc_tx_packet_sz ( audiod_function_t * audio )

inlineprotected

◆ audiod_control_complete()

bool audiod_control_complete	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ audiod_control_request()

bool audiod_control_request	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ audiod_control_xfer_cb()

bool audiod_control_xfer_cb	(	uint8_t	rhport,
		uint8_t	stage,
		tusb_control_request_t const *	request
	)

inlineprotected

◆ audiod_deinit()

bool audiod_deinit ( void )

inlineprotected

◆ audiod_fb_send()

bool audiod_fb_send ( audiod_function_t * audio )

inlineprotected

◆ audiod_get_AS_interface_index()

bool audiod_get_AS_interface_index	(	uint8_t	itf,
		audiod_function_t *	audio,
		uint8_t *	idxItf,
		uint8_t const **	pp_desc_int
	)

inlineprotected

◆ audiod_get_AS_interface_index_global()

bool audiod_get_AS_interface_index_global	(	uint8_t	itf,
		uint8_t *	func_id,
		uint8_t *	idxItf,
		uint8_t const **	pp_desc_int
	)

inlineprotected

◆ audiod_get_interface()

bool audiod_get_interface	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ audiod_init()

void audiod_init ( void )

inlineprotected

◆ audiod_open()

uint16_t audiod_open	(	uint8_t	rhport,
		tusb_desc_interface_t const *	itf_desc,
		uint16_t	max_len
	)

inlineprotected

◆ audiod_parse_flow_control_params()

void audiod_parse_flow_control_params	(	audiod_function_t *	audio,
		uint8_t const *	p_desc
	)

inlineprotected

◆ audiod_reset()

void audiod_reset ( uint8_t rhport )

inlineprotected

◆ audiod_set_fb_params_freq()

bool audiod_set_fb_params_freq	(	audiod_function_t *	audio,
		uint32_t	sample_freq,
		uint32_t	mclk_freq
	)

inlineprotected

◆ audiod_set_interface()

bool audiod_set_interface	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ audiod_sof_isr()

TU_ATTR_FAST_FUNC void audiod_sof_isr	(	uint8_t	rhport,
		uint32_t	frame_count
	)

inlineprotected

◆ audiod_tx_packet_size_fc()

uint16_t audiod_tx_packet_size_fc ( audiod_function_t * audio )

inlineprotected

◆ audiod_verify_entity_exists()

bool audiod_verify_entity_exists	(	uint8_t	itf,
		uint8_t	entityID,
		uint8_t *	func_id
	)

inlineprotected

◆ audiod_verify_ep_exists()

bool audiod_verify_ep_exists	(	uint8_t	ep,
		uint8_t *	func_id
	)

inlineprotected

◆ audiod_verify_itf_exists()

bool audiod_verify_itf_exists	(	uint8_t	itf,
		uint8_t *	func_id
	)

inlineprotected

◆ audiod_xfer_cb()

bool audiod_xfer_cb	(	uint8_t	rhport,
		uint8_t	ep_addr,
		xfer_result_t	result,
		uint32_t	xferred_bytes
	)

inlineprotected

TODO refactor control request handling to separate function and reduce nesting.

◆ audioInfo()

virtual AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in JupyterAudioT< T >, MozziStream, TimerCallbackAudioStream, EncodedAudioStream, PureDataStream, AdapterAudioOutputToAudioStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and InputMerge< T >.

◆ audioInfoOut()

virtual AudioInfo audioInfoOut ( )

inlinevirtualinherited

provides the actual output AudioInfo: this is usually the same as audioInfo() unless we use a transforming stream

Reimplemented in MP3EncoderShine, PureDataStream, PWMAudioOutput< PWMDriverT >, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, Pipeline, ResampleStream, and ResampleStreamT< TInterpolator >.

◆ audioPacketSize()

uint16_t audioPacketSize ( ) const

inline

One isochronous USB packet size in bytes (same formula as the descriptor builder).

◆ available()

int available ( )

inlineoverridevirtual

Bytes of received audio waiting in the RX buffer.

Reimplemented from BaseStream.

◆ availableForWrite()

int availableForWrite ( )

inlineoverridevirtual

Bytes of free space in the TX buffer.

Reimplemented from BaseStream.

◆ begin() [1/2]

bool begin ( )

inlinevirtual

(Re-)start the USB audio device with the current config.

Safe to call more than once: descriptor building, FIFO allocation, and USB stack startup only run on the first call. Subsequent calls just push the current volume/mute/sample-rate state to the host.

Returns: true on success.

Reimplemented from BaseStream.

◆ begin() [2/2]

bool begin ( const USBAudioConfig & cfg )

inline

Apply a config and start the USB audio device.

Before the first begin() all fields may be changed freely. Once started, only the sample rate can change at runtime (via setSampleRate()); descriptor-level fields like channels, bit depth, and endpoint addresses are fixed by the USB enumeration.

Parameters

cfg	Audio configuration.

Returns: true on success.

◆ beginUSB()

virtual bool beginUSB ( )

protectedpure virtual

Override in platform subclasses to register descriptors and start the USB host-controller stack (e.g. USB.begin() on ESP32). Called at the end of begin(cfg, info). The base no-op is correct for RP2040 where TinyUSB is started by the system before setup().

Implemented in USBAudioDeviceESP32, USBAudioDeviceTinyUSB, and USBAudioDeviceTinyUSBFreeRTOS.

◆ bufferRx()

virtual BaseBuffer< uint8_t > & bufferRx ( )

protectedpure virtual

Returns the RX audio buffer. Must be overridden by subclasses.

Implemented in USBAudioDeviceESP32, USBAudioDeviceTinyUSB, and USBAudioDeviceTinyUSBFreeRTOS.

◆ bufferTx()

virtual BaseBuffer< uint8_t > & bufferTx ( )

protectedpure virtual

Returns the TX audio buffer. Must be overridden by subclasses.

Implemented in USBAudioDeviceESP32, USBAudioDeviceTinyUSB, and USBAudioDeviceTinyUSBFreeRTOS.

◆ clearNotifyAudioChange()

virtual void clearNotifyAudioChange ( )

inlinevirtualinherited

Deletes all change notify subscriptions.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

◆ closeEpIn()

void closeEpIn	(	uint8_t	rhport,
		audiod_function_t *	audio,
		uint8_t	itf,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ closeEpOut()

void closeEpOut	(	uint8_t	rhport,
		audiod_function_t *	audio,
		uint8_t	itf,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ configChanged()

bool configChanged ( const USBAudioConfig & n )

inlineprotected

◆ defaultConfig()

USBAudioConfig defaultConfig ( RxTxMode mode = RXTX_MODE )

inline

Returns a default configuration pre-filled for the requested direction (RX_MODE, TX_MODE, or RXTX_MODE). Use TX if you write and rx if you want to read audio data. RXTX is for full duplex.

Parameters

mode	Audio direction.

◆ end()

void end ( )

inlinevirtual

Stop audio streaming and clear FIFOs. Does not disconnect USB.

Reimplemented from BaseStream.

◆ fifoSize()

uint16_t fifoSize ( ) const

inlineprotected

◆ floatToUac2()

static int16_t floatToUac2 ( float vol )

inlinestaticprotected

Convert linear volume (0.0–1.0) to UAC2 int16 (1/256 dB). Linear mapping: 0.0 → -100 dB (min), 1.0 → 0 dB (max).

◆ flush()

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in PureDataStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, ReformatBaseStream, AudioStreamWrapper, ResampleStream, EncodedAudioStream, URLStream, BufferedTaskStream, I2SStream, MemoryStream, RingBufferStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and BufferedStream.

◆ getAudioCount()

uint8_t getAudioCount ( ) const

inline

Returns the number of audio functions (always 1).

◆ getClassDriver()

usbd_class_driver_t const * getClassDriver ( uint8_t * count )

inline

Get the USB device class driver for TinyUSB integration.

Parameters

count Pointer to store the number of drivers (always 1).

Returns: Pointer to the class driver structure.

◆ getCtrlBufSz()

uint16_t getCtrlBufSz ( uint8_t fn ) const

inlineprotected

◆ getDescLen()

uint16_t getDescLen ( uint8_t fn ) const

inlineprotected

◆ getDescriptor()

uint16_t getDescriptor ( uint8_t * desc )

inline

Returns the audio-function descriptor block for use in tud_descriptor_configuration_cb().

Call begin() first so that the config is known. The returned pointer points to an internal static buffer that is valid for the lifetime of the program; copy it into your configuration descriptor buffer.

Parameters

[out] len Total byte count of the returned block.

Returns: Pointer to the audio function descriptor bytes.

◆ getEpInSwBufSz()

uint16_t getEpInSwBufSz ( uint8_t fn ) const

inlineprotected

◆ getEpOutSwBufSz()

uint16_t getEpOutSwBufSz ( uint8_t fn ) const

inlineprotected

◆ getResetSize()

static constexpr size_t getResetSize ( )

inlinestaticconstexprprotected

◆ getRxTotalBytes()

uint32_t getRxTotalBytes ( ) const

inline

Total bytes received from host via OUT endpoint.

◆ getRxXferCount()

uint32_t getRxXferCount ( ) const

inline

Number of times audiod_xfer_cb fired for the OUT endpoint.

◆ getTxBytesPerSample()

uint8_t getTxBytesPerSample ( ) const

inline

TX bytes per sample parsed from the descriptor.

◆ getTxChannels()

uint8_t getTxChannels ( ) const

inline

TX channel count parsed from the descriptor.

◆ getTxFifoReadTotal()

uint32_t getTxFifoReadTotal ( ) const

inline

Total bytes read from ep_in_ff by xfer_cb (should grow at ~176KB/s for 44100Hz stereo 16-bit).

◆ getTxFrameBytesLast()

uint16_t getTxFrameBytesLast ( ) const

inline

Last frame_bytes computed by flow control (should be ~176-180 for 44100Hz).

◆ getTxInterval()

uint8_t getTxInterval ( ) const

inline

TX isochronous interval (bInterval) parsed from the descriptor.

◆ getTxSampleRate()

uint32_t getTxSampleRate ( ) const

inline

TX sample rate parsed from the descriptor (must be non-zero for flow control).

◆ getTxXferCount()

uint32_t getTxXferCount ( ) const

inline

Number of times audiod_xfer_cb fired for the IN endpoint.

◆ getTxXferredLast()

uint32_t getTxXferredLast ( ) const

inline

xferred_bytes from the previous completed transfer (what the DCD actually sent).

◆ getVolumeExt()

float getVolumeExt ( uint8_t channel ) const

inlineprotected

Returns the effective volume for a per-channel index (1-based). Combines master volume (index 0) with per-channel volume and mute.

◆ handleClockSourceGet()

bool handleClockSourceGet	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request,
		uint8_t *	cb
	)

inlineprotected

◆ handleEndpointRequest()

bool handleEndpointRequest	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ handleEntityRequest()

bool handleEntityRequest	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request,
		uint8_t	entityID
	)

inlineprotected

◆ handleFeatureUnitGet()

bool handleFeatureUnitGet	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request,
		uint8_t *	cb
	)

inlineprotected

◆ handleInterfaceRequest()

bool handleInterfaceRequest	(	uint8_t	rhport,
		tusb_control_request_t const *	p_request
	)

inlineprotected

◆ isEpInEnabled()

bool isEpInEnabled ( ) const

inline

Returns true if the IN endpoint is enabled.

◆ isEpInFlowControlEnabled()

bool isEpInFlowControlEnabled ( ) const

inline

Returns true if IN endpoint flow control is enabled. When on, the per-frame isochronous packet size is varied so non-integer sample-per- frame rates (e.g. 44100 Hz) are delivered at the exact average rate.

◆ isEpOutEnabled()

bool isEpOutEnabled ( ) const

inline

Returns true if the OUT endpoint is enabled.

◆ isFeatureUnit()

bool isFeatureUnit ( uint8_t id ) const

inlineprotected

Returns true if the given entity ID is a Feature Unit (FU1 or FU2).

◆ isFeedbackEpEnabled()

bool isFeedbackEpEnabled ( ) const

inline

Returns true if the feedback endpoint is enabled. Only meaningful in pure RX (OUT-only) mode: with an IN endpoint present the host uses the TX stream as implicit feedback instead.

◆ isFifoMutexEnabled()

bool isFifoMutexEnabled ( ) const

inline

Returns true if FIFO mutex is enabled.

◆ isInterruptEpEnabled()

bool isInterruptEpEnabled ( ) const

inline

Returns true if the interrupt endpoint is enabled.

◆ isMute()

bool isMute ( uint8_t channel = 0 ) const

inline

Returns the current mute state for the given channel.

Parameters

channel 0 = master, 1..N = per-channel.

◆ isNotifyActive()

bool isNotifyActive ( )

inlineinherited

Checks if the automatic AudioInfo update is active.

◆ isStreamingActive()

bool isStreamingActive ( ) const

inline

Returns true if either IN or OUT streaming endpoint is open.

◆ isStreamingActiveRx()

bool isStreamingActiveRx ( ) const

inline

Returns true if the host has opened the OUT (playback) stream.

◆ isStreamingActiveTx()

bool isStreamingActiveTx ( ) const

inline

Returns true if the host has opened the IN (capture) stream.

◆ isTxXferArmed()

bool isTxXferArmed ( ) const

inline

True if the initial isochronous IN transfer was armed successfully.

◆ isUseLinearBufferRx()

bool isUseLinearBufferRx ( ) const

inlineprotected

◆ isUseLinearBufferTx()

bool isUseLinearBufferTx ( ) const

inlineprotected

◆ isValidBitsPerSample()

static bool isValidBitsPerSample ( uint8_t bps )

inlinestaticprotected

◆ mounted()

bool mounted ( ) const

inline

Returns true if the device is mounted by the USB host.

◆ not_supported()

virtual int not_supported	(	int	out,
		const char *	msg = `""`
	)

inlineprotectedvirtualinherited

◆ notifyAudioChange()

void notifyAudioChange ( AudioInfo info )

inlineprotectedinherited

◆ notifyStreamingState()

void notifyStreamingState ( )

inlineprotected

◆ numInterfaces()

uint8_t numInterfaces ( ) const

inline

Total number of USB interfaces claimed by the audio function (1 AC + 1 or 2 AS), for use in the bNumInterfaces field of the configuration descriptor.

◆ openEndpointsForAltSetting()

bool openEndpointsForAltSetting	(	uint8_t	rhport,
		audiod_function_t *	audio,
		uint8_t	func_id,
		uint8_t	itf,
		uint8_t	alt
	)

inlineprotected

◆ openEpFeedback()

void openEpFeedback	(	audiod_function_t *	audio,
		tusb_desc_endpoint_t const *	desc_ep
	)

inlineprotected

◆ openEpIn()

void openEpIn	(	uint8_t	rhport,
		audiod_function_t *	audio,
		uint8_t	itf,
		tusb_desc_endpoint_t const *	desc_ep,
		uint8_t const *	p_desc_for_params
	)

inlineprotected

◆ openEpOut()

void openEpOut	(	uint8_t	rhport,
		audiod_function_t *	audio,
		uint8_t	itf,
		tusb_desc_endpoint_t const *	desc_ep
	)

inlineprotected

◆ operator bool()

operator bool ( )

inlineoverridevirtual

Returns true when begin() has been called and the USB host has mounted the device.

Reimplemented from AudioStream.

◆ packetSize()

uint16_t packetSize ( ) const

inlineprotected

◆ processVolume() [1/2]

template<typename T >

void processVolume	(	T *	data,
		size_t	sample_count
	)

inlineprotected

◆ processVolume() [2/2]

void processVolume	(	uint8_t *	data,
		size_t	len
	)

inlineprotected

Process audio data for volume control.

◆ readBytes()

size_t readBytes	(	uint8_t *	buffer,
		size_t	bufsize
	)

inlinevirtual

Receive audio data from the host (host → device, speaker/playback).

Reimplemented from AudioStream.

◆ readSilence()

virtual size_t readSilence	(	uint8_t *	buffer,
		size_t	length
	)

inlinevirtualinherited

Source to generate silence: just sets the buffer to 0.

◆ refillReadBuffer()

void refillReadBuffer ( )

inlineprotectedinherited

Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read()

◆ removeNotifyAudioChange()

virtual bool removeNotifyAudioChange ( AudioInfoSupport & bi )

inlinevirtualinherited

Removes a target in order not to be notified about audio changes.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

◆ resizeBuffers()

virtual void resizeBuffers ( )

protectedpure virtual

Resize the platform audio buffers. Both platforms use NBuffer-style block pools: block size = max USB packet, block count = fifo_packets. ESP32: SynchronizedNBufferRTOS (FreeRTOS queues, cross-core safe). RP2040: NBuffer (single-core, no synchronization needed).

Implemented in USBAudioDeviceESP32, USBAudioDeviceTinyUSB, and USBAudioDeviceTinyUSBFreeRTOS.

◆ sendInterruptNotification()

void sendInterruptNotification	(	uint8_t	ctrlSel,
		uint8_t	channel,
		uint8_t	entityID
	)

inlineprotected

Send a UAC2 status/change notification via the AC interrupt EP.

6-byte message: bInfo(1) bAttribute(1) wValue(2) wIndex(2). The host will re-query the affected control with GET_CUR.

Parameters

ctrlSel	Control selector (e.g. AUDIO_FU_CTRL_VOLUME).
channel	Channel number (0 = master).
entityID	Target entity (Feature Unit or Clock Source).

◆ serviceTinyUSB()

virtual void serviceTinyUSB ( )

inlineprotectedvirtual

Process pending USB events on platforms where the application drives the stack (RP2040, STM32, ...). Skipped when a dedicated FreeRTOS task already calls tud_task() continuously (see usb_task_active_) - tud_task() is not re-entrant; calling it from two contexts concurrently corrupts TinyUSB's internal event queue and causes random hangs.

ESP32 (see USBAudioDeviceESP32) overrides this to an empty no-op, since its own FreeRTOS task already calls tud_task() continuously.

Reimplemented in USBAudioDeviceESP32.

◆ setAudioFeedbackFormatCorrectionCallback()

void setAudioFeedbackFormatCorrectionCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t)> cb )

inline

Register a callback for audio feedback format correction events.

Parameters

cb	Callback function.

◆ setAudioFeedbackParamsCallback()

void setAudioFeedbackParamsCallback ( std::function< void(USBAudioDeviceBase *, uint8_t, uint8_t, audio_feedback_params_t *)> cb )

inline

Register a callback for audio feedback parameter events.

Parameters

cb	Callback function.

◆ setAudioInfo()

void setAudioInfo ( AudioInfo info )

inlineoverridevirtual

Change the sample rate and notify the host.

Reimplemented from AudioStream.

◆ setConfig()

void setConfig ( const USBAudioConfig & cfg )

inlineprotected

Set the USB audio configuration (use begin(cfg) instead).

◆ setFbDoneCallback()

void setFbDoneCallback ( std::function< void(USBAudioDeviceBase *, uint8_t)> cb )

inline

Register a callback for feedback done events.

Parameters

cb	Callback function.

◆ setGetReqEpCallback()

void setGetReqEpCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *)> cb )

inline

Register a callback for GET requests on an endpoint.

Parameters

cb	Callback function.

◆ setGetReqItfCallback()

void setGetReqItfCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *)> cb )

inline

Register a callback for GET requests on the interface.

Parameters

cb	Callback function.

◆ setIntDoneCallback()

void setIntDoneCallback ( std::function< void(USBAudioDeviceBase *, uint8_t)> cb )

inline

Register a callback for interrupt done events.

Parameters

cb	Callback function.

◆ setItfCloseEpCallback()

void setItfCloseEpCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *)> cb )

inline

Register a callback for interface close endpoint events.

Parameters

cb	Callback function.

◆ setMute()

bool setMute	(	bool	m,
		uint8_t	channel = `0`
	)

inline

Set the mute state for a channel and notify the host.

Parameters

m	true = muted, false = unmuted.
channel	0 = master, 1..N = per-channel.

Returns: true if the channel index was valid.

◆ setMuteCallback()

void setMuteCallback ( std::function< void(bool, uint8_t)> cb )

inline

Register a callback invoked when the host (or device) changes the mute state.

Parameters

cb	Callback receiving (bool muted, uint8_t channel).

◆ setNotifyActive()

void setNotifyActive ( bool flag )

inlineinherited

Deactivate/Reactivate automatic AudioInfo updates: (default is active)

◆ setReqEntityCallback() [1/2]

void setReqEntityCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t)> cb )

inline

Register a callback for entity requests.

Parameters

cb	Callback function.

◆ setReqEntityCallback() [2/2]

void setReqEntityCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *, uint8_t *)> cb )

inline

Register a callback for entity set requests.

Parameters

cb	Callback function.

◆ setReqEpCallback()

void setReqEpCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *, uint8_t *)> cb )

inline

Register a callback for endpoint set requests.

Parameters

cb	Callback function.

◆ setReqItfCallback()

void setReqItfCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *, uint8_t *)> cb )

inline

Register a callback for interface set requests.

Parameters

cb	Callback function.

◆ setRxDoneCallback()

void setRxDoneCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, audiod_function_t *, uint16_t)> cb )

inline

Register a callback for RX done events.

Parameters

cb	Callback function.

◆ setSampleRate()

void setSampleRate ( uint32_t rate )

inlineprotected

Device-initiated sample rate change.

Updates the internal config, fires the sample-rate callback, and notifies the host via the AC interrupt endpoint (Clock Source SAM_FREQ CUR). The host will typically re-issue SET_INTERFACE to restart streaming at the new rate.

Parameters

rate	New sample rate in Hz (should be one of the 14 rates advertised in the Clock Source GET_RANGE response).

◆ setSampleRateCallback()

void setSampleRateCallback ( std::function< void(uint32_t)> cb )

inline

Register a callback invoked when the host (or device) changes the sample rate.

Parameters

cb	Callback receiving the new rate in Hz.

◆ setStreamingStateCallback()

void setStreamingStateCallback ( std::function< void(bool, bool)> cb )

inline

Register a callback invoked when the streaming state changes. Fires when the host opens or closes a streaming interface (SET_INTERFACE alt=1 / alt=0).

Parameters

cb	Callback receiving (bool active_tx, bool active_rx).

◆ setTudAudioSetItfCallback()

void setTudAudioSetItfCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, tusb_control_request_t const *)> cb )

inline

Register a callback for interface set requests.

Parameters

cb	Callback function.

◆ setTxDoneCallback()

void setTxDoneCallback ( std::function< bool(USBAudioDeviceBase *, uint8_t, audiod_function_t *)> cb )

inline

Register a callback for TX done events.

Parameters

cb	Callback function.

◆ setupFeedback()

void setupFeedback	(	audiod_function_t *	audio,
		uint8_t	func_id,
		uint8_t	alt
	)

inlineprotected

◆ setVolume() [1/2]

bool setVolume	(	float	vol,
		uint8_t	channel
	)

inline

Set the volume for a channel and notify the host.

Parameters

vol	Volume as a float 0.0 (silence) to 1.0 (0 dB).
channel	0 = master, 1..N = per-channel.

Returns: true if the channel index was valid.

◆ setVolume() [2/2]

bool setVolume ( float volume )

inlineoverridevirtual

sets the volume for the master channel (channel 0)

Reimplemented from VolumeSupport.

◆ setVolumeCallback()

void setVolumeCallback ( std::function< void(float, uint8_t)> cb )

inline

Register a callback invoked when the host (or device) changes the volume.

Parameters

cb	Callback receiving (float volume, uint8_t channel).

◆ setWriteBufferSize()

void setWriteBufferSize ( int size )

inlineinherited

◆ tud_audio_feedback_interval_isr()

void tud_audio_feedback_interval_isr	(	uint8_t	func_id,
		uint32_t	,
		uint8_t	frame_shift
	)

inlineprotected

◆ tud_audio_n_available()

uint16_t tud_audio_n_available ( uint8_t func_id )

inlineprotected

◆ tud_audio_n_read()

uint16_t tud_audio_n_read	(	uint8_t	func_id,
		void *	buffer,
		uint16_t	bufsize
	)

inlineprotected

◆ tud_audio_n_write()

uint16_t tud_audio_n_write	(	uint8_t	func_id,
		const void *	data,
		uint16_t	len
	)

inlineprotected

◆ uac2ToFloat()

static float uac2ToFloat ( int16_t v )

inlinestaticprotected

Convert UAC2 int16 (1/256 dB) to linear volume (0.0–1.0). Linear mapping within the -100..0 dB range reported by GET_RANGE.

◆ volume() [1/2]

float volume ( )

inlineoverridevirtual

gets the volume for the master channel (channel 0)

Reimplemented from VolumeSupport.

◆ volume() [2/2]

float volume ( uint8_t channel )

inline

Returns the current volume for the given channel.

Parameters

channel 0 = master, 1..N = per-channel.

Returns: Volume as a float in the range 0.0 (silence) to 1.0 (0 dB).

◆ write() [1/2]

size_t write	(	const uint8_t *	data,
		size_t	len
	)

inlinevirtual

Send audio data to the host (device → host, microphone/capture). Silently discards data when the host has not opened the capture device (alt=0) so StreamCopy doesn't report write errors before recording.

Reimplemented from AudioStream.

◆ write() [2/2]

virtual size_t write ( uint8_t ch )

inlineoverridevirtualinherited

Reimplemented in MemoryStream, AudioStreamWrapper, BufferedTaskStream, RingBufferStream, BufferedStream, and URLStream.

◆ writeSilence()

virtual void writeSilence ( size_t len )

inlinevirtualinherited

Writes len bytes of silence (=0).

Member Data Documentation

◆ _timeout

int _timeout = 10

protectedinherited

◆ active_config_

USBAudioConfig active_config_

protected

◆ audiod_fct_

std::vector<audiod_function_t> audiod_fct_

protected

◆ config_

USBAudioConfig config_

protected

◆ ctrl_buf_sz_

std::vector<uint16_t> ctrl_buf_sz_

protected

◆ desc_len_

std::vector<uint16_t> desc_len_

protected

◆ descr_builder

USBAudio2DescriptorBuilder descr_builder {config_}

protected

◆ ep_in_sw_buf_sz_

std::vector<uint16_t> ep_in_sw_buf_sz_

protected

◆ ep_out_ff_mutex_rd_

std::vector<osal_mutex_def_t> ep_out_ff_mutex_rd_

protected

◆ ep_out_sw_buf_sz_

std::vector<uint16_t> ep_out_sw_buf_sz_

protected

◆ fb_done_cb_

std::function<void(USBAudioDeviceBase*, uint8_t func_id)> fb_done_cb_

protected

◆ get_req_ep_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const*)> get_req_ep_cb_

protected

◆ get_req_itf_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const*)> get_req_itf_cb_

protected

◆ info

AudioInfo info

protectedinherited

◆ int_done_cb_

std::function<void(USBAudioDeviceBase*, uint8_t rhport)> int_done_cb_

protected

◆ int_notify_buf_

uint8_t int_notify_buf_[6] = {}

protected

◆ is_active_

bool is_active_ = false

protected

◆ is_notify_active

bool is_notify_active = true

protectedinherited

◆ is_started_

bool is_started_ = false

protected

◆ kVolumeMinDb256

constexpr int16_t kVolumeMinDb256 = -25600

staticconstexprprotected

Convert AudioTools volume (0.0–1.0) to UAC2 int16 (1/256 dB). 0.0 maps to 0x8000 (silence), 1.0 maps to 0 (0 dB).

◆ mute_

std::vector<bool> mute_

protected

◆ mute_cb_

std::function<void(bool, uint8_t)> mute_cb_

protected

◆ notify_vector

Vector<AudioInfoSupport*> notify_vector

protectedinherited

◆ req_entity_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t func_id)> req_entity_cb_

protected

◆ rx_done_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, audiod_function_t*, uint16_t xferred_bytes)> rx_done_cb_

protected

◆ rx_total_bytes_

volatile uint32_t rx_total_bytes_ = 0

protected

◆ s_active_

USBAudioDeviceBase* s_active_ = nullptr

inlinestaticprotected

◆ sample_rate_cb_

std::function<void(uint32_t)> sample_rate_cb_

protected

◆ streaming_state_cb_

std::function<void(bool, bool)> streaming_state_cb_

protected

◆ tmp_in

RingBuffer<uint8_t> tmp_in {0}

protectedinherited

◆ tmp_out

RingBuffer<uint8_t> tmp_out {0}

protectedinherited

◆ tud_audio_feedback_format_correction_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t func_id)> tud_audio_feedback_format_correction_cb_

protected

◆ tud_audio_feedback_params_cb_

std::function<void(USBAudioDeviceBase*, uint8_t func_id, uint8_t alt_itf, audio_feedback_params_t* feedback_param)> tud_audio_feedback_params_cb_

protected

◆ tud_audio_set_itf_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const* p_request)> tud_audio_set_itf_cb_

protected

◆ tud_audio_set_itf_close_EP_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const* p_request)> tud_audio_set_itf_close_EP_cb_

protected

◆ tud_audio_set_req_entity_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const* p_request, uint8_t* pBuff)> tud_audio_set_req_entity_cb_

protected

◆ tud_audio_set_req_ep_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const* p_request, uint8_t* pBuff)> tud_audio_set_req_ep_cb_

protected

◆ tud_audio_set_req_itf_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, tusb_control_request_t const* p_request, uint8_t* pBuff)> tud_audio_set_req_itf_cb_

protected

◆ tx_done_cb_

std::function<bool(USBAudioDeviceBase*, uint8_t rhport, audiod_function_t*)> tx_done_cb_

protected

◆ tx_fifo_read_total_

volatile uint32_t tx_fifo_read_total_ = 0

protected

◆ tx_frame_bytes_last_

volatile uint16_t tx_frame_bytes_last_ = 0

protected

◆ tx_xfer_armed_

bool tx_xfer_armed_ = false

protected

◆ tx_xferred_last_

volatile uint32_t tx_xferred_last_ = 0

protected

◆ usb_task_active_

bool usb_task_active_ = false

protected

◆ volume_

std::vector<float> volume_

protected

◆ volume_cb_

std::function<void(float, uint8_t)> volume_cb_

protected

◆ volume_value

float volume_value = 1.0f

protectedinherited

◆ write_buffer_size

int write_buffer_size = MAX_SINGLE_CHARS

protectedinherited

◆ xfer_cb_rx_count_

volatile uint32_t xfer_cb_rx_count_ = 0

protected

◆ xfer_cb_tx_count_

volatile uint32_t xfer_cb_tx_count_ = 0

protected

The documentation for this class was generated from the following file:

src/AudioTools/Communication/USB/USBAudioDeviceBase.h

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ USBAudioDeviceBase() [1/2]

◆ USBAudioDeviceBase() [2/2]

Member Function Documentation

◆ activateEndpoint()

◆ activeInstance()

◆ addNotifyAudioChange()

◆ alloc_mutex()

◆ audiod_calc_tx_packet_sz()

◆ audiod_control_complete()

◆ audiod_control_request()

◆ audiod_control_xfer_cb()

◆ audiod_deinit()

◆ audiod_fb_send()

◆ audiod_get_AS_interface_index()

◆ audiod_get_AS_interface_index_global()

◆ audiod_get_interface()

◆ audiod_init()

◆ audiod_open()

◆ audiod_parse_flow_control_params()

◆ audiod_reset()

◆ audiod_set_fb_params_freq()

◆ audiod_set_interface()

◆ audiod_sof_isr()

◆ audiod_tx_packet_size_fc()

◆ audiod_verify_entity_exists()

◆ audiod_verify_ep_exists()

◆ audiod_verify_itf_exists()

◆ audiod_xfer_cb()

◆ audioInfo()

◆ audioInfoOut()

◆ audioPacketSize()

◆ available()

◆ availableForWrite()

◆ begin() [1/2]

◆ begin() [2/2]

◆ beginUSB()

◆ bufferRx()

◆ bufferTx()

◆ clearNotifyAudioChange()

◆ closeEpIn()

◆ closeEpOut()

◆ configChanged()

◆ defaultConfig()

◆ end()

◆ fifoSize()

◆ floatToUac2()

◆ flush()

◆ getAudioCount()

◆ getClassDriver()

◆ getCtrlBufSz()

◆ getDescLen()

◆ getDescriptor()

◆ getEpInSwBufSz()

◆ getEpOutSwBufSz()

◆ getResetSize()

◆ getRxTotalBytes()

◆ getRxXferCount()

◆ getTxBytesPerSample()

◆ getTxChannels()

◆ getTxFifoReadTotal()

◆ getTxFrameBytesLast()

◆ getTxInterval()

◆ getTxSampleRate()

◆ getTxXferCount()

◆ getTxXferredLast()

◆ getVolumeExt()

◆ handleClockSourceGet()

◆ handleEndpointRequest()

◆ handleEntityRequest()

◆ handleFeatureUnitGet()

◆ handleInterfaceRequest()

◆ isEpInEnabled()