sdk/fidl/fuchsia.hardware.audio/codec.fidl

// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

library fuchsia.hardware.audio;

using zx;

/// Textual information about the codec.
struct CodecInfo {
    /// Unique identifier for the codec.
    string:UNIQUE_ID_SIZE unique_id;

    /// Name of the codec manufacturer.
    string:MAX_UI_STRING_SIZE manufacturer;

    /// Product name of the codec.
    string:MAX_UI_STRING_SIZE product_name;
};

/// Gain type of representation.
enum GainType : uint8 {
    /// Gain specified in dB, for example -103.0dB or +3.2dB.
    DECIBELS = 1;

    /// Gain specified as a percentage, for example 10.0% or 80.5%.
    PERCENT = 2;
};

/// Gain format/parameters.
table GainFormat {
    /// Specifies what the numbers for gain represent, e.g. a percentage.
    1: GainType type;

    /// Minimum gain. Must be included.
    2: float32 min_gain;

    /// Maximum gain. Must be included.
    3: float32 max_gain;

    /// Gain step in decibels, this value must not be negative, but may be zero to convey an
    /// effectively continuous range of values. Must not exceed `max_gain_db` - `min_gain_db`.
    /// Must be included.
    4: float32 gain_step;

    /// Gain mute capability. If not included, mute is not supported.
    5: bool can_mute;

    /// Automatic Gain Control (AGC) capability. If not included, AGC is not supported.
    6: bool can_agc;
};

/// For an overview see
/// [Audio Codec Interface](//docs/concepts/drivers/driver_interfaces/audio_codec.md)
protocol Codec {
    /// Resets the codec.
    /// `Reset` returns when the reset is completed. If the driver can't successfully reset the
    /// codec it will close the codec protocol channel, in this case the client may obtain a new
    /// codec protocol channel and retry.
    Reset() -> ();

    /// Retrieves textual information about the codec.
    GetInfo() -> (CodecInfo info);

    /// Stops the codec operation.
    /// `Stop` returns when stopping the codec is completed. If the driver can't successfully stop
    /// the codec it will close the codec protocol channel, in this case the client may obtain a new
    /// codec protocol channel and retry.
    Stop() -> ();

    /// Start/Re-start the codec operation.
    /// `Start` returns when starting the codec is completed. If the driver can't successfully start
    /// the codec it will close the codec protocol channel, in this case the client may obtain a new
    /// codec protocol channel and retry.
    Start() -> ();

    /// Retrieves bridgeable mode from a codec.
    IsBridgeable() -> (bool supports_bridged_mode);

    /// Sets a codec's bridged mode.  Only required if the codec supports bridged mode as specified
    /// by IsBridgeable's reply.
    SetBridgedMode(bool enable_bridged_mode);

    /// Retrieves the DAI formats supported by the codec, if not available at the time the codec
    /// may reply with an error status and the controller may retry at a later time.
    /// Retrieving multiple DaiSupportedFormats allows for cases where exclusive
    /// combinations of the parameters in DaiSupportedFormats may be supported.
    GetDaiFormats() -> (vector<DaiSupportedFormats>:MAX_COUNT_FORMATS formats)
        error zx.status;

    /// Sets the DAI format to be used in the interface between the controller and codec, if
    /// the codec is not able to support the DAI format anymore, e.g. for a removable component
    /// then the function may return an error status.
    SetDaiFormat(DaiFormat format) -> (zx.status status);

    /// Retrieves gain format.
    GetGainFormat() -> (GainFormat gain_format);

    /// Retrieves Plug Detect Capabilities.
    GetPlugDetectCapabilities() -> (PlugDetectCapabilities plug_detect_capabilities);

    /// Get the gain state via a hanging get. The driver will reply to the first `WatchGainState`
    /// sent by the client and this reply must include a `gain_db` set to 0dB or lower. The driver
    /// will not respond to subsequent client `WatchGainState` calls until the gain state changes
    /// from what was most recently reported.
    WatchGainState() -> (GainState gain_state);

    /// Client update of the gain state.
    SetGainState(GainState target_state);

    /// Get the plug detect state via a hanging get. The driver will reply to the first
    /// `WatchPlugState` sent by the client. The driver will not respond to subsequent client
    /// `WatchPlugState` calls until the plug state changes from what was most recently reported.
    WatchPlugState() -> (PlugState plug_state);
};