5 files changed, 62 insertions, 2 deletions
diff --git a/audio/4.0/IDevice.hal b/audio/4.0/IDevice.hal
index 4bc2d4db0..591e56509 100644
--- a/audio/4.0/IDevice.hal
+++ b/audio/4.0/IDevice.hal
@@ -109,6 +109,8 @@ interface IDevice {
      * @param device device type and (if needed) address.
      * @param config stream configuration.
      * @param flags additional flags.
+     * @param sourceMetadata Description of the audio that will be played.
+                             May be used by implementations to configure hardware effects.
      * @return retval operation completion status.
      * @return outStream created output stream.
      * @return suggestedConfig in case of invalid parameters, suggested config.
@@ -117,7 +119,8 @@ interface IDevice {
             AudioIoHandle ioHandle,
             DeviceAddress device,
             AudioConfig config,
-            bitfield<AudioOutputFlag> flags) generates (
+            bitfield<AudioOutputFlag> flags,
+            SourceMetadata sourceMetadata) generates (
                     Result retval,
                     IStreamOut outStream,
                     AudioConfig suggestedConfig);
@@ -132,6 +135,8 @@ interface IDevice {
      * @param config stream configuration.
      * @param flags additional flags.
      * @param source source specification.
+     * @param sinkMetadata Description of the audio that is suggested by the client.
+     *                     May be used by implementations to configure hardware effects.
      * @return retval operation completion status.
      * @return inStream in case of success, created input stream.
      * @return suggestedConfig in case of invalid parameters, suggested config.
@@ -141,7 +146,7 @@ interface IDevice {
             DeviceAddress device,
             AudioConfig config,
             bitfield<AudioInputFlag> flags,
-            AudioSource source) generates (
+            SinkMetadata sinkMetadata) generates (
                     Result retval,
                     IStreamIn inStream,
                     AudioConfig suggestedConfig);
diff --git a/audio/4.0/IStreamIn.hal b/audio/4.0/IStreamIn.hal
index ea2826ea3..3b1fd40c5 100644
--- a/audio/4.0/IStreamIn.hal
+++ b/audio/4.0/IStreamIn.hal
@@ -84,6 +84,12 @@ interface IStreamIn extends IStream {
     };
 
     /**
+     * Called when the metadata of the stream's sink has been changed.
+     * @param sinkMetadata Description of the audio that is suggested by the clients.
+     */
+    updateSinkMetadata(SinkMetadata sinkMetadata);
+
+    /**
      * Set up required transports for receiving audio buffers from the driver.
      *
      * The transport consists of three message queues:
diff --git a/audio/4.0/IStreamOut.hal b/audio/4.0/IStreamOut.hal
index 02f169730..585bffed6 100644
--- a/audio/4.0/IStreamOut.hal
+++ b/audio/4.0/IStreamOut.hal
@@ -78,6 +78,12 @@ interface IStreamOut extends IStream {
     };
 
     /**
+     * Called when the metadata of the stream's source has been changed.
+     * @param sourceMetadata Description of the audio that is played by the clients.
+     */
+    updateSourceMetadata(SourceMetadata sourceMetadata);
+
+    /**
      * Set up required transports for passing audio buffers to the driver.
      *
      * The transport consists of three message queues:
diff --git a/audio/4.0/types.hal b/audio/4.0/types.hal
index 5c95e4be2..1563b36cf 100644
--- a/audio/4.0/types.hal
+++ b/audio/4.0/types.hal
@@ -117,3 +117,36 @@ enum MessageQueueFlagBits : uint32_t {
     NOT_EMPTY = 1 << 0,
     NOT_FULL = 1 << 1
 };
+
+/** Metadata of a playback track for a StreamOut. */
+struct PlaybackTrackMetadata {
+    AudioUsage usage;
+    AudioContentType contentType;
+    /**
+     * Positive linear gain applied to the track samples. 0 being muted and 1 is no attenuation,
+     * 2 means double amplification...
+     * Must not be negative.
+     */
+    float gain;
+};
+
+/** Metadatas of the source of a StreamOut. */
+struct SourceMetadata {
+    vec<PlaybackTrackMetadata> tracks;
+};
+
+/** Metadata of a record track for a StreamIn. */
+struct RecordTrackMetadata {
+    AudioSource source;
+    /**
+     * Positive linear gain applied to the track samples. 0 being muted and 1 is no attenuation,
+     * 2 means double amplification...
+     * Must not be negative.
+     */
+    float gain;
+};
+
+/** Metadatas of the source of a StreamIn. */
+struct SinkMetadata {
+    vec<RecordTrackMetadata> tracks;
+};
diff --git a/audio/common/4.0/types.hal b/audio/common/4.0/types.hal
index e9e717366..b1c15f321 100644
--- a/audio/common/4.0/types.hal
+++ b/audio/common/4.0/types.hal
@@ -671,6 +671,16 @@ enum AudioUsage : int32_t {
     ASSISTANT                          = 16,
 };
 
+/** Type of audio generated by an application. */
+@export(name="audio_content_type_t", value_prefix="AUDIO_CONTENT_TYPE_")
+enum AudioContentType : uint32_t {
+    UNKNOWN      = 0,
+    SPEECH       = 1,
+    MUSIC        = 2,
+    MOVIE        = 3,
+    SONIFICATION = 4,
+};
+
 /**
  * Additional information about the stream passed to hardware decoders.
  */