uac2_ops Struct Reference

USB Audio 2 application event handlers. More...

#include <usbd_uac2.h>

Data Fields
void(*	sof_cb )(const struct device *dev, void *user_data)
	Start of Frame callback.
void(*	terminal_update_cb )(const struct device *dev, uint8_t terminal, bool enabled, bool microframes, void *user_data)
	Terminal update callback.
void *(*	get_recv_buf )(const struct device *dev, uint8_t terminal, uint16_t size, void *user_data)
	Get receive buffer address.
void(*	data_recv_cb )(const struct device *dev, uint8_t terminal, void *buf, uint16_t size, void *user_data)
	Data received.
void(*	buf_release_cb )(const struct device *dev, uint8_t terminal, void *buf, void *user_data)
	Transmit buffer release callback.
uint32_t(*	feedback_cb )(const struct device *dev, uint8_t terminal, void *user_data)
	Get Explicit Feedback value.

Detailed Description

USB Audio 2 application event handlers.

Field Documentation

buf_release_cb

void(* uac2_ops::buf_release_cb) (const struct device *dev, uint8_t terminal, void *buf, void *user_data)

Transmit buffer release callback.

This function releases buffer provided in usbd_uac2_send when the class no longer needs it.

Parameters

dev	USB Audio 2 device
terminal	Output Terminal ID linked to AudioStreaming interface
buf	Buffer previously provided via usbd_uac2_send
user_data	Opaque user data pointer

data_recv_cb

void(* uac2_ops::data_recv_cb) (const struct device *dev, uint8_t terminal, void *buf, uint16_t size, void *user_data)

Data received.

This function releases buffer obtained in get_recv_buf after USB has written data to the buffer and/or no longer needs it.

Parameters

dev	USB Audio 2 device
terminal	Input Terminal ID linked to AudioStreaming interface
buf	Buffer previously obtained via get_recv_buf
size	Number of bytes written to buffer
user_data	Opaque user data pointer

feedback_cb

uint32_t(* uac2_ops::feedback_cb) (const struct device *dev, uint8_t terminal, void *user_data)

Get Explicit Feedback value.

Explicit feedback value format depends terminal connection speed. If device is High-Speed capable, it must use Q16.16 format if and only if the terminal_update_cb was called with microframes parameter set to true. On Full-Speed only devices, or if High-Speed capable device is operating at Full-Speed (microframes was false), the format is Q10.14 stored on 24 least significant bits (i.e. 8 most significant bits are ignored).

Parameters

dev	USB Audio 2 device
terminal	Input Terminal ID whose feedback should be returned
user_data	Opaque user data pointer

get_recv_buf

void *(* uac2_ops::get_recv_buf) (const struct device *dev, uint8_t terminal, uint16_t size, void *user_data)

Get receive buffer address.

USB stack calls this function to obtain receive buffer address for AudioStreaming interface. The buffer is owned by USB stack until data_recv_cb callback is called. The buffer must be sufficiently aligned and otherwise suitable for use by UDC driver.

Parameters

dev	USB Audio 2 device
terminal	Input Terminal ID linked to AudioStreaming interface
size	Maximum number of bytes USB stack will write to buffer.
user_data	Opaque user data pointer

sof_cb

void(* uac2_ops::sof_cb) (const struct device *dev, void *user_data)

Start of Frame callback.

Notifies application about SOF event on the bus.

Parameters

dev	USB Audio 2 device
user_data	Opaque user data pointer

terminal_update_cb

void(* uac2_ops::terminal_update_cb) (const struct device *dev, uint8_t terminal, bool enabled, bool microframes, void *user_data)

Terminal update callback.

Notifies application that host has enabled or disabled a terminal.

Parameters

dev	USB Audio 2 device
terminal	Terminal ID linked to AudioStreaming interface
enabled	True if host enabled terminal, False otherwise
microframes	True if USB connection speed uses microframes
user_data	Opaque user data pointer

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

• include/zephyr/usb/class/usbd_uac2.h