diff --git a/media/libaudioclient/AidlConversion.cpp b/media/libaudioclient/AidlConversion.cpp
index 8f3d996..fa78f43 100644
--- a/media/libaudioclient/AidlConversion.cpp
+++ b/media/libaudioclient/AidlConversion.cpp
@@ -412,10 +412,205 @@
 namespace {
 
 namespace detail {
+using AudioDevicePair = std::pair<audio_devices_t, media::AudioDeviceDescription>;
+using AudioDevicePairs = std::vector<AudioDevicePair>;
 using AudioFormatPair = std::pair<audio_format_t, media::AudioFormatDescription>;
 using AudioFormatPairs = std::vector<AudioFormatPair>;
 }
 
+media::AudioDeviceDescription make_AudioDeviceDescription(media::AudioDeviceType type,
+        const std::string& connection = "") {
+    media::AudioDeviceDescription result;
+    result.type = type;
+    result.connection = connection;
+    return result;
+}
+
+void append_AudioDeviceDescription(detail::AudioDevicePairs& pairs,
+        audio_devices_t inputType, audio_devices_t outputType,
+        media::AudioDeviceType inType, media::AudioDeviceType outType,
+        const std::string& connection = "") {
+    pairs.push_back(std::make_pair(inputType, make_AudioDeviceDescription(inType, connection)));
+    pairs.push_back(std::make_pair(outputType, make_AudioDeviceDescription(outType, connection)));
+}
+
+const detail::AudioDevicePairs& getAudioDevicePairs() {
+    static const detail::AudioDevicePairs pairs = []() {
+        detail::AudioDevicePairs pairs = {{
+            {
+                AUDIO_DEVICE_NONE, media::AudioDeviceDescription{}
+            },
+            {
+                AUDIO_DEVICE_OUT_EARPIECE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_SPEAKER_EARPIECE)
+            },
+            {
+                AUDIO_DEVICE_OUT_SPEAKER, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_SPEAKER)
+            },
+            {
+                AUDIO_DEVICE_OUT_WIRED_HEADPHONE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_HEADPHONE,
+                        media::AudioDeviceDescription::CONNECTION_ANALOG())
+            },
+            {
+                AUDIO_DEVICE_OUT_BLUETOOTH_SCO, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_DEVICE,
+                        media::AudioDeviceDescription::CONNECTION_BT_SCO())
+            },
+            {
+                AUDIO_DEVICE_OUT_BLUETOOTH_SCO_CARKIT, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_CARKIT,
+                        media::AudioDeviceDescription::CONNECTION_BT_SCO())
+            },
+            {
+                AUDIO_DEVICE_OUT_BLUETOOTH_A2DP_HEADPHONES, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_HEADPHONE,
+                        media::AudioDeviceDescription::CONNECTION_BT_A2DP())
+            },
+            {
+                AUDIO_DEVICE_OUT_BLUETOOTH_A2DP_SPEAKER, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_SPEAKER,
+                        media::AudioDeviceDescription::CONNECTION_BT_A2DP())
+            },
+            {
+                AUDIO_DEVICE_OUT_TELEPHONY_TX, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_TELEPHONY_TX)
+            },
+            {
+                AUDIO_DEVICE_OUT_AUX_LINE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_LINE_AUX)
+            },
+            {
+                AUDIO_DEVICE_OUT_SPEAKER_SAFE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_SPEAKER_SAFE)
+            },
+            {
+                AUDIO_DEVICE_OUT_HEARING_AID, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_HEARING_AID,
+                        media::AudioDeviceDescription::CONNECTION_WIRELESS())
+            },
+            {
+                AUDIO_DEVICE_OUT_ECHO_CANCELLER, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_ECHO_CANCELLER)
+            },
+            {
+                AUDIO_DEVICE_OUT_BLE_SPEAKER, make_AudioDeviceDescription(
+                        media::AudioDeviceType::OUT_SPEAKER,
+                        media::AudioDeviceDescription::CONNECTION_BT_LE())
+            },
+            // AUDIO_DEVICE_IN_AMBIENT and IN_COMMUNICATION are removed since they were deprecated.
+            {
+                AUDIO_DEVICE_IN_BUILTIN_MIC, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_MICROPHONE)
+            },
+            {
+                AUDIO_DEVICE_IN_BACK_MIC, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_MICROPHONE_BACK)
+            },
+            {
+                AUDIO_DEVICE_IN_TELEPHONY_RX, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_TELEPHONY_RX)
+            },
+            {
+                AUDIO_DEVICE_IN_TV_TUNER, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_TV_TUNER)
+            },
+            {
+                AUDIO_DEVICE_IN_LOOPBACK, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_LOOPBACK)
+            },
+            {
+                AUDIO_DEVICE_IN_BLUETOOTH_BLE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_DEVICE,
+                        media::AudioDeviceDescription::CONNECTION_BT_LE())
+            },
+            {
+                AUDIO_DEVICE_IN_ECHO_REFERENCE, make_AudioDeviceDescription(
+                        media::AudioDeviceType::IN_ECHO_REFERENCE)
+            }
+        }};
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_DEFAULT, AUDIO_DEVICE_OUT_DEFAULT,
+                media::AudioDeviceType::IN_DEFAULT, media::AudioDeviceType::OUT_DEFAULT);
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_WIRED_HEADSET, AUDIO_DEVICE_OUT_WIRED_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_ANALOG());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_BLUETOOTH_SCO_HEADSET, AUDIO_DEVICE_OUT_BLUETOOTH_SCO_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_BT_SCO());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_HDMI, AUDIO_DEVICE_OUT_HDMI,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_HDMI());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_REMOTE_SUBMIX, AUDIO_DEVICE_OUT_REMOTE_SUBMIX,
+                media::AudioDeviceType::IN_SUBMIX, media::AudioDeviceType::OUT_SUBMIX);
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_ANLG_DOCK_HEADSET, AUDIO_DEVICE_OUT_ANLG_DOCK_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_ANALOG_DOCK());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_DGTL_DOCK_HEADSET, AUDIO_DEVICE_OUT_DGTL_DOCK_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_DIGITAL_DOCK());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_USB_ACCESSORY, AUDIO_DEVICE_OUT_USB_ACCESSORY,
+                media::AudioDeviceType::IN_ACCESSORY, media::AudioDeviceType::OUT_ACCESSORY,
+                media::AudioDeviceDescription::CONNECTION_USB());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_USB_DEVICE, AUDIO_DEVICE_OUT_USB_DEVICE,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_USB());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_FM_TUNER, AUDIO_DEVICE_OUT_FM,
+                media::AudioDeviceType::IN_FM_TUNER, media::AudioDeviceType::OUT_FM);
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_LINE, AUDIO_DEVICE_OUT_LINE,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_ANALOG());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_SPDIF, AUDIO_DEVICE_OUT_SPDIF,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_SPDIF());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_BLUETOOTH_A2DP, AUDIO_DEVICE_OUT_BLUETOOTH_A2DP,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_BT_A2DP());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_IP, AUDIO_DEVICE_OUT_IP,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_IP_V4());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_BUS, AUDIO_DEVICE_OUT_BUS,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_BUS());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_PROXY, AUDIO_DEVICE_OUT_PROXY,
+                media::AudioDeviceType::IN_AFE_PROXY, media::AudioDeviceType::OUT_AFE_PROXY);
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_USB_HEADSET, AUDIO_DEVICE_OUT_USB_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_USB());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_HDMI_ARC, AUDIO_DEVICE_OUT_HDMI_ARC,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_HDMI_ARC());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_HDMI_EARC, AUDIO_DEVICE_OUT_HDMI_EARC,
+                media::AudioDeviceType::IN_DEVICE, media::AudioDeviceType::OUT_DEVICE,
+                media::AudioDeviceDescription::CONNECTION_HDMI_EARC());
+        append_AudioDeviceDescription(pairs,
+                AUDIO_DEVICE_IN_BLE_HEADSET, AUDIO_DEVICE_OUT_BLE_HEADSET,
+                media::AudioDeviceType::IN_HEADSET, media::AudioDeviceType::OUT_HEADSET,
+                media::AudioDeviceDescription::CONNECTION_BT_LE());
+        return pairs;
+    }();
+    return pairs;
+}
+
 media::AudioFormatDescription make_AudioFormatDescription(media::AudioFormatType type) {
     media::AudioFormatDescription result;
     result.type = type;
@@ -768,19 +963,55 @@
     return pairs;
 }
 
+template<typename S, typename T>
+std::unordered_map<S, T> make_DirectMap(const std::vector<std::pair<S, T>>& v) {
+    std::unordered_map<S, T> result(v.begin(), v.end());
+    LOG_ALWAYS_FATAL_IF(result.size() != v.size(), "Duplicate key elements detected");
+    return result;
+}
+
+template<typename S, typename T>
+std::unordered_map<T, S> make_ReverseMap(const std::vector<std::pair<S, T>>& v) {
+    std::unordered_map<T, S> result;
+    std::transform(v.begin(), v.end(), std::inserter(result, result.begin()),
+            [](const std::pair<S, T>& p) {
+                return std::make_pair(p.second, p.first);
+            });
+    LOG_ALWAYS_FATAL_IF(result.size() != v.size(), "Duplicate key elements detected");
+    return result;
+}
+
 }  // namespace
 
+ConversionResult<audio_devices_t> aidl2legacy_AudioDeviceDescription_audio_devices_t(
+        const media::AudioDeviceDescription& aidl) {
+    static const std::unordered_map<media::AudioDeviceDescription, audio_devices_t> m =
+            make_ReverseMap(getAudioDevicePairs());
+    if (auto it = m.find(aidl); it != m.end()) {
+        return it->second;
+    } else {
+        ALOGE("%s: no legacy audio_devices_t found for %s", __func__, aidl.toString().c_str());
+        return unexpected(BAD_VALUE);
+    }
+}
+
+ConversionResult<media::AudioDeviceDescription> legacy2aidl_audio_devices_t_AudioDeviceDescription(
+        audio_devices_t legacy) {
+    static const std::unordered_map<audio_devices_t, media::AudioDeviceDescription> m =
+            make_DirectMap(getAudioDevicePairs());
+    if (auto it = m.find(legacy); it != m.end()) {
+        return it->second;
+    } else {
+        ALOGE("%s: no AudioDeviceDescription found for legacy audio_devices_t value 0x%x",
+                __func__, legacy);
+        return unexpected(BAD_VALUE);
+    }
+}
+
 ConversionResult<audio_format_t> aidl2legacy_AudioFormatDescription_audio_format_t(
         const media::AudioFormatDescription& aidl) {
     static const std::unordered_map<media::AudioFormatDescription, audio_format_t> m =
-            [](const detail::AudioFormatPairs& f) {
-                std::unordered_map<media::AudioFormatDescription, audio_format_t> r;
-                std::transform(f.begin(), f.end(), std::inserter(r, r.begin()),
-                        [](const detail::AudioFormatPair& p) {
-                            return std::make_pair(p.second, p.first);
-                        });
-                return r;
-            }(getAudioFormatPairs());
+            make_ReverseMap(getAudioFormatPairs());
     if (auto it = m.find(aidl); it != m.end()) {
         return it->second;
     } else {
@@ -792,9 +1023,7 @@
 ConversionResult<media::AudioFormatDescription> legacy2aidl_audio_format_t_AudioFormatDescription(
         audio_format_t legacy) {
     static const std::unordered_map<audio_format_t, media::AudioFormatDescription> m =
-            [](const detail::AudioFormatPairs& f) {
-                return std::unordered_map<audio_format_t, media::AudioFormatDescription>(
-                        f.begin(), f.end()); }(getAudioFormatPairs());
+            make_DirectMap(getAudioFormatPairs());
     if (auto it = m.find(legacy); it != m.end()) {
         return it->second;
     } else {
diff --git a/media/libaudioclient/Android.bp b/media/libaudioclient/Android.bp
index 809a26b..a23c844 100644
--- a/media/libaudioclient/Android.bp
+++ b/media/libaudioclient/Android.bp
@@ -309,6 +309,8 @@
         "aidl/android/media/AudioConfigBase.aidl",
         "aidl/android/media/AudioContentType.aidl",
         "aidl/android/media/AudioDevice.aidl",
+        "aidl/android/media/AudioDeviceDescription.aidl",
+        "aidl/android/media/AudioDeviceType.aidl",
         "aidl/android/media/AudioDualMonoMode.aidl",
         "aidl/android/media/AudioEncapsulationMode.aidl",
         "aidl/android/media/AudioEncapsulationMetadataType.aidl",
diff --git a/media/libaudioclient/aidl/android/media/AudioDeviceDescription.aidl b/media/libaudioclient/aidl/android/media/AudioDeviceDescription.aidl
new file mode 100644
index 0000000..f7548b9
--- /dev/null
+++ b/media/libaudioclient/aidl/android/media/AudioDeviceDescription.aidl
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.media;
+
+import android.media.AudioDeviceType;
+
+parcelable AudioDeviceDescription {
+    /**
+     * Type and directionality of the device. For bidirectional audio devices
+     * two descriptions need to be created, having the same value for
+     * the 'connection' field.
+     *
+     * See 'AudioDeviceType' for the list of supported values.
+     */
+    AudioDeviceType type = AudioDeviceType.NONE;
+    /**
+     * Specifies the type of the connection of the device to the audio system.
+     * Usually it's some kind of a communication protocol, e.g. Bluetooth SCO or
+     * USB. There is a list of connection types recognized by the framework,
+     * defined using 'CONNECTION_' constants. Vendors can add their own
+     * connection types with "vx.<vendor>." prefix.
+     *
+     * When the 'connection' field is left empty and 'type != NONE | DEFAULT',
+     * it is assumed that the device is permanently attached to the audio
+     * system, e.g. a built-in speaker or microphone.
+     *
+     * The 'connection' field must be left empty if 'type' is 'NONE' or
+     * '{IN|OUT}_DEFAULT'.
+     */
+    @utf8InCpp String connection;
+    /**
+     * Analog connection, for example, via 3.5 mm analog jack.
+     */
+    const @utf8InCpp String CONNECTION_ANALOG = "analog";
+    /**
+     * Low-End (Analog) Desk Dock.
+     */
+    const @utf8InCpp String CONNECTION_ANALOG_DOCK = "analog-dock";
+    /**
+     * Bluetooth A2DP connection.
+     */
+    const @utf8InCpp String CONNECTION_BT_A2DP = "bt-a2dp";
+    /**
+     * Bluetooth Low Energy (LE) connection.
+     */
+    const @utf8InCpp String CONNECTION_BT_LE = "bt-le";
+    /**
+     * Bluetooth SCO connection.
+     */
+    const @utf8InCpp String CONNECTION_BT_SCO = "bt-sco";
+    /**
+     * Bus connection. Mostly used in automotive scenarios.
+     */
+    const @utf8InCpp String CONNECTION_BUS = "bus";
+    /**
+     * High-End (Digital) Desk Dock.
+     */
+    const @utf8InCpp String CONNECTION_DIGITAL_DOCK = "digital-dock";
+    /**
+     * HDMI connection.
+     */
+    const @utf8InCpp String CONNECTION_HDMI = "hdmi";
+    /**
+     * HDMI ARC connection.
+     */
+    const @utf8InCpp String CONNECTION_HDMI_ARC = "hdmi-arc";
+    /**
+     * HDMI eARC connection.
+     */
+    const @utf8InCpp String CONNECTION_HDMI_EARC = "hdmi-earc";
+    /**
+     * IP v4 connection.
+     */
+    const @utf8InCpp String CONNECTION_IP_V4 = "ip-v4";
+    /**
+     * SPDIF connection.
+     */
+    const @utf8InCpp String CONNECTION_SPDIF = "spdif";
+    /**
+     * A wireless connection when the actual protocol is unspecified.
+     */
+    const @utf8InCpp String CONNECTION_WIRELESS = "wireless";
+    /**
+     * USB connection.
+     */
+    const @utf8InCpp String CONNECTION_USB = "usb";
+}
diff --git a/media/libaudioclient/aidl/android/media/AudioDeviceType.aidl b/media/libaudioclient/aidl/android/media/AudioDeviceType.aidl
new file mode 100644
index 0000000..4da9fd6
--- /dev/null
+++ b/media/libaudioclient/aidl/android/media/AudioDeviceType.aidl
@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.media;
+
+/**
+ * The type of the audio device. Only used as part of 'AudioDeviceDescription'
+ * structure.
+ *
+ * Types are divided into "input" and "output" categories. Audio devices that
+ * have both audio input and output, for example, headsets, are represented by a
+ * pair of input and output device types.
+ *
+ * The 'AudioDeviceType' intentionally binds together directionality and 'kind'
+ * of the device to avoid making them fully orthogonal. This is because not all
+ * types of devices are bidirectional, for example, speakers can only be used
+ * for output and microphones can only be used for input (at least, in the
+ * context of the audio framework).
+ */
+@Backing(type="int")
+enum AudioDeviceType {
+    /**
+     * "None" type is a "null" value. All fields of 'AudioDeviceDescription'
+     * must have default / empty / null values.
+     */
+    NONE = 0,
+    /**
+     * The "default" device is used when the client does not have any
+     * preference for a particular device.
+     */
+    IN_DEFAULT = 1,
+    /**
+     * A device implementing Android Open Accessory protocol.
+     */
+    IN_ACCESSORY = 2,
+    /**
+     * Input from a DSP front-end proxy device.
+     */
+    IN_AFE_PROXY = 3,
+    /**
+     * Used when only the connection protocol is known, e.g. a "HDMI Device."
+     */
+    IN_DEVICE = 4,
+    /**
+     * A device providing reference input for echo canceller.
+     */
+    IN_ECHO_REFERENCE = 5,
+    /**
+     * FM Tuner input.
+     */
+    IN_FM_TUNER = 6,
+    /**
+     * A microphone of a headset.
+     */
+    IN_HEADSET = 7,
+    /**
+     * Loopback input.
+     */
+    IN_LOOPBACK = 8,
+    /**
+     * The main microphone (the frontal mic on mobile devices).
+     */
+    IN_MICROPHONE = 9,
+    /**
+     * The secondary microphone (the back mic on mobile devices).
+     */
+    IN_MICROPHONE_BACK = 10,
+    /**
+     * Input from a submix of other streams.
+     */
+    IN_SUBMIX = 11,
+    /**
+     * Audio received via the telephone line.
+     */
+    IN_TELEPHONY_RX = 12,
+    /**
+     * TV Tuner audio input.
+     */
+    IN_TV_TUNER = 13,
+    /**
+     * The "default" device is used when the client does not have any
+     * preference for a particular device.
+     */
+    OUT_DEFAULT = 129,
+    /**
+     * A device implementing Android Open Accessory protocol.
+     */
+    OUT_ACCESSORY = 130,
+    /**
+     * Output from a DSP front-end proxy device.
+     */
+    OUT_AFE_PROXY = 131,
+    /**
+     * Car audio system.
+     */
+    OUT_CARKIT = 132,
+    /**
+     * Used when only the connection protocol is known, e.g. a "HDMI Device."
+     */
+    OUT_DEVICE = 133,
+    /**
+     * The echo canceller device.
+     */
+    OUT_ECHO_CANCELLER = 134,
+    /**
+     * The FM Tuner device.
+     */
+    OUT_FM = 135,
+    /**
+     * Headphones.
+     */
+    OUT_HEADPHONE = 136,
+    /**
+     * Headphones of a headset.
+     */
+    OUT_HEADSET = 137,
+    /**
+     * Hearing aid.
+     */
+    OUT_HEARING_AID = 138,
+    /**
+     * Secondary line level output.
+     */
+    OUT_LINE_AUX = 139,
+    /**
+     * The main speaker.
+     */
+    OUT_SPEAKER = 140,
+    /**
+     * The speaker of a mobile device in the case when it is close to the ear.
+     */
+    OUT_SPEAKER_EARPIECE = 141,
+    /**
+     * The main speaker with overload / overheating protection.
+     */
+    OUT_SPEAKER_SAFE = 142,
+    /**
+     * Output into a submix.
+     */
+    OUT_SUBMIX = 143,
+    /**
+     * Output into a telephone line.
+     */
+    OUT_TELEPHONY_TX = 144,
+}
diff --git a/media/libaudioclient/include/media/AidlConversion.h b/media/libaudioclient/include/media/AidlConversion.h
index 305dbc3..422d94f 100644
--- a/media/libaudioclient/include/media/AidlConversion.h
+++ b/media/libaudioclient/include/media/AidlConversion.h
@@ -25,6 +25,7 @@
 #include <android/media/AudioClient.h>
 #include <android/media/AudioConfig.h>
 #include <android/media/AudioConfigBase.h>
+#include <android/media/AudioDeviceDescription.h>
 #include <android/media/AudioDualMonoMode.h>
 #include <android/media/AudioEncapsulationMode.h>
 #include <android/media/AudioEncapsulationMetadataType.h>
@@ -139,6 +140,11 @@
 ConversionResult<media::AudioFormatSys> legacy2aidl_audio_format_t_AudioFormat(
         audio_format_t legacy);
 
+ConversionResult<audio_devices_t> aidl2legacy_AudioDeviceDescription_audio_devices_t(
+        const media::AudioDeviceDescription& aidl);
+ConversionResult<media::AudioDeviceDescription> legacy2aidl_audio_devices_t_AudioDeviceDescription(
+        audio_devices_t legacy);
+
 ConversionResult<audio_format_t> aidl2legacy_AudioFormatDescription_audio_format_t(
         const media::AudioFormatDescription& aidl);
 ConversionResult<media::AudioFormatDescription> legacy2aidl_audio_format_t_AudioFormatDescription(
diff --git a/media/libaudioclient/include/media/AudioCommonTypes.h b/media/libaudioclient/include/media/AudioCommonTypes.h
index 607b99c..613d6bd 100644
--- a/media/libaudioclient/include/media/AudioCommonTypes.h
+++ b/media/libaudioclient/include/media/AudioCommonTypes.h
@@ -19,6 +19,7 @@
 
 #include <functional>
 
+#include <android/media/AudioDeviceDescription.h>
 #include <android/media/AudioFormatDescription.h>
 #include <binder/Parcelable.h>
 #include <system/audio.h>
@@ -36,9 +37,18 @@
 
 namespace std {
 
-// Note: when extending AudioFormatDescription we need to account for the
+// Note: when extending Audio{Device|Format}Description we need to account for the
 // possibility of comparison between different versions of it, e.g. a HAL
 // may be using a previous version of the AIDL interface.
+template<> struct hash<android::media::AudioDeviceDescription>
+{
+    std::size_t operator()(const android::media::AudioDeviceDescription& add) const noexcept {
+        return hash_combine(
+                std::hash<android::media::AudioDeviceType>{}(add.type),
+                std::hash<std::string>{}(add.connection));
+    }
+};
+
 template<> struct hash<android::media::AudioFormatDescription>
 {
     std::size_t operator()(const android::media::AudioFormatDescription& afd) const noexcept {
diff --git a/media/libaudioclient/tests/audio_aidl_legacy_conversion_tests.cpp b/media/libaudioclient/tests/audio_aidl_legacy_conversion_tests.cpp
index e4bc9f0..ca609ab 100644
--- a/media/libaudioclient/tests/audio_aidl_legacy_conversion_tests.cpp
+++ b/media/libaudioclient/tests/audio_aidl_legacy_conversion_tests.cpp
@@ -24,10 +24,44 @@
 
 namespace {
 
-size_t afdHash(const media::AudioFormatDescription& afd) {
+size_t hash(const media::AudioDeviceDescription& add) {
+    return std::hash<media::AudioDeviceDescription>{}(add);
+}
+
+size_t hash(const media::AudioFormatDescription& afd) {
     return std::hash<media::AudioFormatDescription>{}(afd);
 }
 
+media::AudioDeviceDescription make_AudioDeviceDescription(media::AudioDeviceType type,
+        const std::string& connection = "") {
+    media::AudioDeviceDescription result;
+    result.type = type;
+    result.connection = connection;
+    return result;
+}
+
+media::AudioDeviceDescription make_ADD_None() {
+    return media::AudioDeviceDescription{};
+}
+
+media::AudioDeviceDescription make_ADD_DefaultIn() {
+    return make_AudioDeviceDescription(media::AudioDeviceType::IN_DEFAULT);
+}
+
+media::AudioDeviceDescription make_ADD_DefaultOut() {
+    return make_AudioDeviceDescription(media::AudioDeviceType::OUT_DEFAULT);
+}
+
+media::AudioDeviceDescription make_ADD_WiredHeadset() {
+    return make_AudioDeviceDescription(media::AudioDeviceType::OUT_HEADSET,
+            media::AudioDeviceDescription::CONNECTION_ANALOG());
+}
+
+media::AudioDeviceDescription make_ADD_BtScoHeadset() {
+    return make_AudioDeviceDescription(media::AudioDeviceType::OUT_HEADSET,
+            media::AudioDeviceDescription::CONNECTION_BT_SCO());
+}
+
 media::AudioFormatDescription make_AudioFormatDescription(media::AudioFormatType type) {
     media::AudioFormatDescription result;
     result.type = type;
@@ -53,6 +87,10 @@
     return result;
 }
 
+media::AudioFormatDescription make_AFD_Default() {
+    return media::AudioFormatDescription{};
+}
+
 media::AudioFormatDescription make_AFD_Invalid() {
     return make_AudioFormatDescription(media::AudioFormatType::SYS_RESERVED_INVALID);
 }
@@ -77,25 +115,53 @@
 
 }  // namespace
 
-// Verify that two independently constructed AFDs have the same hash.
-// This ensures that regardless of whether the AFD instance originates
-// from, it can be correctly compared to other AFD instance. Thus,
+// Verify that two independently constructed ADDs/AFDs have the same hash.
+// This ensures that regardless of whether the ADD/AFD instance originates
+// from, it can be correctly compared to other ADD/AFD instance. Thus,
 // for example, a 16-bit integer format description provided by HAL
 // is identical to the same format description constructed by the framework.
-TEST(audio_aidl_legacy_conversion_tests, AudioFormatDescriptionHashIdentity) {
-    EXPECT_EQ(afdHash(make_AFD_Invalid()), afdHash(make_AFD_Invalid()));
-    EXPECT_EQ(afdHash(media::AudioFormatDescription{}), afdHash(media::AudioFormatDescription{}));
-    EXPECT_EQ(afdHash(make_AFD_Pcm16Bit()), afdHash(make_AFD_Pcm16Bit()));
-    EXPECT_NE(afdHash(media::AudioFormatDescription{}), afdHash(make_AFD_Invalid()));
-    EXPECT_NE(afdHash(media::AudioFormatDescription{}), afdHash(make_AFD_Pcm16Bit()));
-    EXPECT_EQ(afdHash(make_AFD_Bitstream()), afdHash(make_AFD_Bitstream()));
-    EXPECT_NE(afdHash(make_AFD_Pcm16Bit()), afdHash(make_AFD_Bitstream()));
-    EXPECT_EQ(afdHash(make_AFD_Encap()), afdHash(make_AFD_Encap()));
-    EXPECT_NE(afdHash(make_AFD_Pcm16Bit()), afdHash(make_AFD_Encap()));
-    EXPECT_EQ(afdHash(make_AFD_Encap_with_Enc()), afdHash(make_AFD_Encap_with_Enc()));
-    EXPECT_NE(afdHash(make_AFD_Encap()), afdHash(make_AFD_Encap_with_Enc()));
+class HashIdentityTest : public ::testing::Test {
+  public:
+    template<typename T> void verifyHashIdentity(const std::vector<std::function<T()>>& valueGens) {
+        for (size_t i = 0; i < valueGens.size(); ++i) {
+            for (size_t j = 0; j < valueGens.size(); ++j) {
+                if (i == j) {
+                    EXPECT_EQ(hash(valueGens[i]()), hash(valueGens[i]())) << i;
+                } else {
+                    EXPECT_NE(hash(valueGens[i]()), hash(valueGens[j]())) << i << ", " << j;
+                }
+            }
+        }
+    }
+};
+
+TEST_F(HashIdentityTest, AudioDeviceDescriptionHashIdentity) {
+    verifyHashIdentity<media::AudioDeviceDescription>({
+            make_ADD_None, make_ADD_DefaultIn, make_ADD_DefaultOut, make_ADD_WiredHeadset,
+            make_ADD_BtScoHeadset});
 }
 
+TEST_F(HashIdentityTest, AudioFormatDescriptionHashIdentity) {
+    verifyHashIdentity<media::AudioFormatDescription>({
+            make_AFD_Default, make_AFD_Invalid, make_AFD_Pcm16Bit, make_AFD_Bitstream,
+            make_AFD_Encap, make_AFD_Encap_with_Enc});
+}
+
+class AudioDeviceDescriptionRoundTripTest :
+        public testing::TestWithParam<media::AudioDeviceDescription> {};
+TEST_P(AudioDeviceDescriptionRoundTripTest, Aidl2Legacy2Aidl) {
+    const auto initial = GetParam();
+    auto conv = aidl2legacy_AudioDeviceDescription_audio_devices_t(initial);
+    ASSERT_TRUE(conv.ok());
+    auto convBack = legacy2aidl_audio_devices_t_AudioDeviceDescription(conv.value());
+    ASSERT_TRUE(convBack.ok());
+    EXPECT_EQ(initial, convBack.value());
+}
+INSTANTIATE_TEST_SUITE_P(AudioDeviceDescriptionRoundTrip,
+        AudioDeviceDescriptionRoundTripTest,
+        testing::Values(media::AudioDeviceDescription{}, make_ADD_DefaultIn(),
+                make_ADD_DefaultOut(), make_ADD_WiredHeadset(), make_ADD_BtScoHeadset()));
+
 class AudioFormatDescriptionRoundTripTest :
         public testing::TestWithParam<media::AudioFormatDescription> {};
 TEST_P(AudioFormatDescriptionRoundTripTest, Aidl2Legacy2Aidl) {