feat(usb): Prepare embassy-usb for USB Audio, and add USB Audio Class 1.0 (playback only)

embassy-usb/src/class/mod.rs

@@ -3,4 +3,5 @@ pub mod cdc_acm;
 pub mod cdc_ncm;
 pub mod hid;
 pub mod midi;
+pub mod uac1;
 pub mod web_usb;

embassy-usb/src/class/uac1/class_codes.rs

@@ -0,0 +1,151 @@
+//! Audio Device Class Codes as defined in Universal Serial Bus Device Class
+//! Definition for Audio Devices, Release 1.0, Appendix A and Universal Serial
+//! Bus Device Class Definition for Audio Data Formats, Release 1.0, Appendix
+//! A.1.1 (Audio Data Format Type I Codes)
+#![allow(dead_code)]
+
+/// The current version of the ADC specification (1.0)
+pub const ADC_VERSION: u16 = 0x0100;
+
+/// The current version of the USB device (1.0)
+pub const DEVICE_VERSION: u16 = 0x0100;
+
+/// Audio Interface Class Code
+pub const USB_AUDIO_CLASS: u8 = 0x01;
+
+// Audio Interface Subclass Codes
+pub const USB_UNDEFINED_SUBCLASS: u8 = 0x00;
+pub const USB_AUDIOCONTROL_SUBCLASS: u8 = 0x01;
+pub const USB_AUDIOSTREAMING_SUBCLASS: u8 = 0x02;
+pub const USB_MIDISTREAMING_SUBCLASS: u8 = 0x03;
+
+// Audio Protocol Code
+pub const PROTOCOL_NONE: u8 = 0x00;
+
+// Audio Class-Specific Descriptor Types
+pub const CS_UNDEFINED: u8 = 0x20;
+pub const CS_DEVICE: u8 = 0x21;
+pub const CS_CONFIGURATION: u8 = 0x22;
+pub const CS_STRING: u8 = 0x23;
+pub const CS_INTERFACE: u8 = 0x24;
+pub const CS_ENDPOINT: u8 = 0x25;
+
+// Descriptor Subtype
+pub const AC_DESCRIPTOR_UNDEFINED: u8 = 0x00;
+pub const HEADER_SUBTYPE: u8 = 0x01;
+pub const INPUT_TERMINAL: u8 = 0x02;
+pub const OUTPUT_TERMINAL: u8 = 0x03;
+pub const MIXER_UNIT: u8 = 0x04;
+pub const SELECTOR_UNIT: u8 = 0x05;
+pub const FEATURE_UNIT: u8 = 0x06;
+pub const PROCESSING_UNIT: u8 = 0x07;
+pub const EXTENSION_UNIT: u8 = 0x08;
+
+// Audio Class-Specific AS Interface Descriptor Subtypes
+pub const AS_DESCRIPTOR_UNDEFINED: u8 = 0x00;
+pub const AS_GENERAL: u8 = 0x01;
+pub const FORMAT_TYPE: u8 = 0x02;
+pub const FORMAT_SPECIFIC: u8 = 0x03;
+
+// Processing Unit Process Types
+pub const PROCESS_UNDEFINED: u16 = 0x00;
+pub const UP_DOWNMIX_PROCESS: u16 = 0x01;
+pub const DOLBY_PROLOGIC_PROCESS: u16 = 0x02;
+pub const DDD_STEREO_EXTENDER_PROCESS: u16 = 0x03;
+pub const REVERBERATION_PROCESS: u16 = 0x04;
+pub const CHORUS_PROCESS: u16 = 0x05;
+pub const DYN_RANGE_COMP_PROCESS: u16 = 0x06;
+
+// Audio Class-Specific Endpoint Descriptor Subtypes
+pub const EP_DESCRIPTOR_UNDEFINED: u8 = 0x00;
+pub const EP_GENERAL: u8 = 0x01;
+
+// Audio Class-Specific Request Codes
+pub const REQUEST_CODE_UNDEFINED: u8 = 0x00;
+pub const SET_CUR: u8 = 0x01;
+pub const GET_CUR: u8 = 0x81;
+pub const SET_MIN: u8 = 0x02;
+pub const GET_MIN: u8 = 0x82;
+pub const SET_MAX: u8 = 0x03;
+pub const GET_MAX: u8 = 0x83;
+pub const SET_RES: u8 = 0x04;
+pub const GET_RES: u8 = 0x84;
+pub const SET_MEM: u8 = 0x05;
+pub const GET_MEM: u8 = 0x85;
+pub const GET_STAT: u8 = 0xFF;
+
+// Terminal Control Selectors
+pub const TE_CONTROL_UNDEFINED: u8 = 0x00;
+pub const COPY_PROTECT_CONTROL: u8 = 0x01;
+
+// Feature Unit Control Selectors
+pub const FU_CONTROL_UNDEFINED: u8 = 0x00;
+pub const MUTE_CONTROL: u8 = 0x01;
+pub const VOLUME_CONTROL: u8 = 0x02;
+pub const BASS_CONTROL: u8 = 0x03;
+pub const MID_CONTROL: u8 = 0x04;
+pub const TREBLE_CONTROL: u8 = 0x05;
+pub const GRAPHIC_EQUALIZER_CONTROL: u8 = 0x06;
+pub const AUTOMATIC_GAIN_CONTROL: u8 = 0x07;
+pub const DELAY_CONTROL: u8 = 0x08;
+pub const BASS_BOOST_CONTROL: u8 = 0x09;
+pub const LOUDNESS_CONTROL: u8 = 0x0A;
+
+// Up/Down-mix Processing Unit Control Selectors
+pub const UD_CONTROL_UNDEFINED: u8 = 0x00;
+pub const UD_ENABLE_CONTROL: u8 = 0x01;
+pub const UD_MODE_SELECT_CONTROL: u8 = 0x02;
+
+// Dolby Prologic Processing Unit Control Selectors
+pub const DP_CONTROL_UNDEFINED: u8 = 0x00;
+pub const DP_ENABLE_CONTROL: u8 = 0x01;
+pub const DP_MODE_SELECT_CONTROL: u8 = 0x2;
+
+// 3D Stereo Extender Processing Unit Control Selectors
+pub const DDD_CONTROL_UNDEFINED: u8 = 0x00;
+pub const DDD_ENABLE_CONTROL: u8 = 0x01;
+pub const DDD_SPACIOUSNESS_CONTROL: u8 = 0x03;
+
+// Reverberation Processing Unit Control Selectors
+pub const RV_CONTROL_UNDEFINED: u8 = 0x00;
+pub const RV_ENABLE_CONTROL: u8 = 0x01;
+pub const REVERB_LEVEL_CONTROL: u8 = 0x02;
+pub const REVERB_TIME_CONTROL: u8 = 0x03;
+pub const REVERB_FEEDBACK_CONTROL: u8 = 0x04;
+
+// Chorus Processing Unit Control Selectors
+pub const CH_CONTROL_UNDEFINED: u8 = 0x00;
+pub const CH_ENABLE_CONTROL: u8 = 0x01;
+pub const CHORUS_LEVEL_CONTROL: u8 = 0x02;
+pub const CHORUS_RATE_CONTROL: u8 = 0x03;
+pub const CHORUS_DEPTH_CONTROL: u8 = 0x04;
+
+// Dynamic Range Compressor Processing Unit Control Selectors
+pub const DR_CONTROL_UNDEFINED: u8 = 0x00;
+pub const DR_ENABLE_CONTROL: u8 = 0x01;
+pub const COMPRESSION_RATE_CONTROL: u8 = 0x02;
+pub const MAXAMPL_CONTROL: u8 = 0x03;
+pub const THRESHOLD_CONTROL: u8 = 0x04;
+pub const ATTACK_TIME: u8 = 0x05;
+pub const RELEASE_TIME: u8 = 0x06;
+
+// Extension Unit Control Selectors
+pub const XU_CONTROL_UNDEFINED: u16 = 0x00;
+pub const XU_ENABLE_CONTROL: u16 = 0x01;
+
+// Endpoint Control Selectors
+pub const EP_CONTROL_UNDEFINED: u8 = 0x00;
+pub const SAMPLING_FREQ_CONTROL: u8 = 0x01;
+pub const PITCH_CONTROL: u8 = 0x02;
+
+// Format Type Codes
+pub const FORMAT_TYPE_UNDEFINED: u8 = 0x00;
+pub const FORMAT_TYPE_I: u8 = 0x01;
+
+// Audio Data Format Type I Codes
+pub const TYPE_I_UNDEFINED: u16 = 0x0000;
+pub const PCM: u16 = 0x0001;
+pub const PCM8: u16 = 0x0002;
+pub const IEEE_FLOAT: u16 = 0x0003;
+pub const ALAW: u16 = 0x0004;
+pub const MULAW: u16 = 0x0005;

embassy-usb/src/class/uac1/mod.rs

@@ -0,0 +1,134 @@
+//! USB Audio Class 1.0 implementations for different applications.
+//!
+//! Contains:
+//! - The `speaker` class with a single audio streaming interface (host to device)
+
+pub mod speaker;
+
+mod class_codes;
+mod terminal_type;
+
+/// The maximum supported audio channel index (corresponds to `Top`).
+/// FIXME: Use `core::mem::variant_count(...)` when stabilized.
+const MAX_AUDIO_CHANNEL_INDEX: usize = 12;
+
+/// The maximum number of supported audio channels.
+///
+/// Includes all twelve channels from `Channel`, plus the Master channel.
+const MAX_AUDIO_CHANNEL_COUNT: usize = MAX_AUDIO_CHANNEL_INDEX + 1;
+
+/// USB Audio Channel
+#[derive(Debug, Clone, Copy, PartialEq)]
+#[allow(missing_docs)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub enum Channel {
+    LeftFront,
+    RightFront,
+    CenterFront,
+    Lfe,
+    LeftSurround,
+    RightSurround,
+    LeftOfCenter,
+    RightOfCenter,
+    Surround,
+    SideLeft,
+    SideRight,
+    Top,
+}
+
+impl Channel {
+    /// Map a `Channel` to its corresponding USB Audio `ChannelConfig`.
+    fn get_channel_config(&self) -> ChannelConfig {
+        match self {
+            Channel::LeftFront => ChannelConfig::LeftFront,
+            Channel::RightFront => ChannelConfig::RightFront,
+            Channel::CenterFront => ChannelConfig::CenterFront,
+            Channel::Lfe => ChannelConfig::Lfe,
+            Channel::LeftSurround => ChannelConfig::LeftSurround,
+            Channel::RightSurround => ChannelConfig::RightSurround,
+            Channel::LeftOfCenter => ChannelConfig::LeftOfCenter,
+            Channel::RightOfCenter => ChannelConfig::RightOfCenter,
+            Channel::Surround => ChannelConfig::Surround,
+            Channel::SideLeft => ChannelConfig::SideLeft,
+            Channel::SideRight => ChannelConfig::SideRight,
+            Channel::Top => ChannelConfig::Top,
+        }
+    }
+}
+
+/// USB Audio Channel configuration
+#[repr(u16)]
+#[non_exhaustive]
+// #[derive(Copy, Clone, Eq, PartialEq, Debug)]
+enum ChannelConfig {
+    None = 0x0000,
+    LeftFront = 0x0001,
+    RightFront = 0x0002,
+    CenterFront = 0x0004,
+    Lfe = 0x0008,
+    LeftSurround = 0x0010,
+    RightSurround = 0x0020,
+    LeftOfCenter = 0x0040,
+    RightOfCenter = 0x0080,
+    Surround = 0x0100,
+    SideLeft = 0x0200,
+    SideRight = 0x0400,
+    Top = 0x0800,
+}
+
+impl From<ChannelConfig> for u16 {
+    fn from(t: ChannelConfig) -> u16 {
+        t as u16
+    }
+}
+
+/// Feedback period adjustment `bRefresh` [UAC 3.7.2.2]
+///
+/// From the specification: "A new Ff value is available every 2^(10 – P) frames with P ranging from 1 to 9. The
+/// bRefresh field of the synch standard endpoint descriptor is used to report the exponent (10-P) to the Host."
+///
+/// This means:
+/// - 512 ms (2^9 frames) to 2 ms (2^1 frames) for USB full-speed
+/// - 64 ms (2^9 microframes) to 0.25 ms (2^1 microframes) for USB high-speed
+#[repr(u8)]
+#[allow(missing_docs)]
+#[derive(Clone, Copy)]
+pub enum FeedbackRefresh {
+    Period2Frames = 1,
+    Period4Frames = 2,
+    Period8Frames = 3,
+    Period16Frames = 4,
+    Period32Frames = 5,
+    Period64Frames = 6,
+    Period128Frames = 7,
+    Period256Frames = 8,
+    Period512Frames = 9,
+}
+
+impl FeedbackRefresh {
+    /// Gets the number of frames, after which a new feedback frame is returned.
+    pub const fn frame_count(&self) -> usize {
+        1 << (*self as usize)
+    }
+}
+
+/// Audio sample width.
+///
+/// Stored in number of bytes per sample.
+#[repr(u8)]
+#[derive(Clone, Copy)]
+pub enum SampleWidth {
+    /// 16 bit audio
+    Width2Byte = 2,
+    /// 24 bit audio
+    Width3Byte = 3,
+    /// 32 bit audio
+    Width4Byte = 4,
+}
+
+impl SampleWidth {
+    /// Get the audio sample resolution in number of bit.
+    pub const fn in_bit(self) -> usize {
+        8 * self as usize
+    }
+}