Module uac 

USB Audio Class (UAC) handler module.

This module provides functionality for interacting with USB Audio Class devices, including device registration, control requests, and audio streaming.

Overview

The UAC handler supports:

• Device enumeration and interface discovery
• Control requests for audio parameters (volume, mute, sampling frequency, etc.)
• Isochronous audio streaming with feedback
• String descriptor retrieval
• Range queries for supported parameter values

See the UAC specification for more details.

Usage

// Register a UAC device
let handler = UacHandler::try_register(&bus, enum_info).await?;

// Get current sampling frequency
let freq = handler.get_sampling_freq(terminal_id).await?;

// Start audio output stream. The callback is called repeatedly whenever the buffer is ready to be filled.
let mut output = handler.output()?;
output.output_stream(|buffer| {
    // Fill buffer with audio data
}).await?;

Modules

codes

USB Audio Device Class constants from UAC2 specification Based on USB Device Class Definition for Audio Devices, Release 2.0 (May 31, 2006)

descriptors

USB Audio Class (UAC) descriptor parsing and management.

Structs

Layout1ParameterBlock

Parameter block for range queries with 1-byte values.

Layout2ParameterBlock

Parameter block for range queries with 2-byte values.

Layout3ParameterBlock

Parameter block for range queries with 4-byte values.

Range1

Represents a range of 1-byte (u8) values.

Range2

Represents a range of 2-byte (u16) values.

Range4

Represents a range of 4-byte (u32) values.

UacHandler

Handler for USB Audio Class (UAC) devices, providing control and streaming functionality.

UacOut

Represents an output audio stream to a USB Audio Class (UAC) device.

Enums

RequestError

Errors that can occur during UAC request handling.

Functions

parse_feedback

Parse USB feedback endpoint response into a floating point number.