diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamIn.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamIn.aidl
index 98acf5f..68f1ff3 100644
--- a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamIn.aidl
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamIn.aidl
@@ -41,9 +41,13 @@
   float getMicrophoneFieldDimension();
   void setMicrophoneFieldDimension(float zoom);
   void updateMetadata(in android.hardware.audio.common.SinkMetadata sinkMetadata);
+  float[] getHwGain();
+  void setHwGain(in float[] channelGains);
   const int MIC_FIELD_DIMENSION_WIDE_ANGLE = -1;
   const int MIC_FIELD_DIMENSION_NO_ZOOM = 0;
   const int MIC_FIELD_DIMENSION_MAX_ZOOM = 1;
+  const int HW_GAIN_MIN = 0;
+  const int HW_GAIN_MAX = 1;
   @Backing(type="int") @VintfStability
   enum MicrophoneDirection {
     UNSPECIFIED = 0,
diff --git a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamOut.aidl b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamOut.aidl
index 5ea2a12..092b801 100644
--- a/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamOut.aidl
+++ b/audio/aidl/aidl_api/android.hardware.audio.core/current/android/hardware/audio/core/IStreamOut.aidl
@@ -36,4 +36,8 @@
 interface IStreamOut {
   android.hardware.audio.core.IStreamCommon getStreamCommon();
   void updateMetadata(in android.hardware.audio.common.SourceMetadata sourceMetadata);
+  float[] getHwVolume();
+  void setHwVolume(in float[] channelVolumes);
+  const int HW_VOLUME_MIN = 0;
+  const int HW_VOLUME_MAX = 1;
 }
diff --git a/audio/aidl/android/hardware/audio/core/IStreamIn.aidl b/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
index 92788a6..c2b3633 100644
--- a/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
+++ b/audio/aidl/android/hardware/audio/core/IStreamIn.aidl
@@ -131,4 +131,38 @@
      * @throws EX_ILLEGAL_STATE If the stream is closed.
      */
     void updateMetadata(in SinkMetadata sinkMetadata);
+
+    const int HW_GAIN_MIN = 0;
+    const int HW_GAIN_MAX = 1;
+    /**
+     * Retrieve current gain applied in hardware.
+     *
+     * In case when the HAL module has a gain controller, this method returns
+     * the current value of its gain for each input channel.
+     *
+     * The valid range for gain is [0.0f, 1.0f], where 1.0f corresponds to unity
+     * gain, 0.0f corresponds to full mute (see HW_GAIN_* constants).
+     *
+     * @return Current gain values for each input channel.
+     * @throws EX_ILLEGAL_STATE If the stream is closed.
+     * @throws EX_UNSUPPORTED_OPERATION If hardware gain control is not supported.
+     */
+    float[] getHwGain();
+    /**
+     * Set gain applied in hardware.
+     *
+     * In case when the HAL module has a gain controller, this method sets the
+     * current value of its gain for each input channel.
+     *
+     * The valid range for gain is [0.0f, 1.0f], where 1.0f corresponds to unity
+     * gain, 0.0f corresponds to full mute (see HW_GAIN_* constants).
+     *
+     * @param gain Gain values for each input channel.
+     * @throws EX_ILLEGAL_ARGUMENT If the number of elements in the provided
+     *                             array does not match the channel count, or
+     *                             gain values are out of range.
+     * @throws EX_ILLEGAL_STATE If the stream is closed.
+     * @throws EX_UNSUPPORTED_OPERATION If hardware gain control is not supported.
+     */
+    void setHwGain(in float[] channelGains);
 }
diff --git a/audio/aidl/android/hardware/audio/core/IStreamOut.aidl b/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
index f7fc77a..85da00d 100644
--- a/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
+++ b/audio/aidl/android/hardware/audio/core/IStreamOut.aidl
@@ -44,4 +44,46 @@
      * @throws EX_ILLEGAL_STATE If the stream is closed.
      */
     void updateMetadata(in SourceMetadata sourceMetadata);
+
+    const int HW_VOLUME_MIN = 0;
+    const int HW_VOLUME_MAX = 1;
+    /**
+     * Retrieve current attenuation applied in hardware.
+     *
+     * Hardware attenuation can be used in cases when the client can not, or is
+     * not allowed to modify the audio stream, for example because the stream is
+     * encoded.
+     *
+     * The valid range for attenuation is [0.0f, 1.0f], where 1.0f corresponds
+     * to unity gain, 0.0f corresponds to full mute (see HW_VOLUME_*
+     * constants). The returned array specifies attenuation for each output
+     * channel of the stream.
+     *
+     * Support of hardware volume control is optional.
+     *
+     * @return Current attenuation values for each output channel.
+     * @throws EX_ILLEGAL_STATE If the stream is closed.
+     * @throws EX_UNSUPPORTED_OPERATION If hardware volume control is not supported.
+     */
+    float[] getHwVolume();
+    /**
+     * Set attenuation applied in hardware.
+     *
+     * Hardware attenuation can be used in cases when the client can not, or is
+     * not allowed to modify the audio stream, for example because the stream is
+     * encoded.
+     *
+     * The valid range for attenuation is [0.0f, 1.0f], where 1.0f corresponds
+     * to unity gain, 0.0f corresponds to full mute (see HW_VOLUME_* constants).
+     *
+     * Support of hardware volume control is optional.
+     *
+     * @param channelVolumes Attenuation values for each output channel.
+     * @throws EX_ILLEGAL_ARGUMENT If the number of elements in the provided
+     *                             array does not match the channel count, or
+     *                             attenuation values are out of range.
+     * @throws EX_ILLEGAL_STATE If the stream is closed.
+     * @throws EX_UNSUPPORTED_OPERATION If hardware volume control is not supported.
+     */
+    void setHwVolume(in float[] channelVolumes);
 }
diff --git a/audio/aidl/default/Stream.cpp b/audio/aidl/default/Stream.cpp
index 424c3e4..e984091 100644
--- a/audio/aidl/default/Stream.cpp
+++ b/audio/aidl/default/Stream.cpp
@@ -658,6 +658,17 @@
     return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
 }
 
+ndk::ScopedAStatus StreamIn::getHwGain(std::vector<float>* _aidl_return) {
+    LOG(DEBUG) << __func__;
+    (void)_aidl_return;
+    return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+}
+
+ndk::ScopedAStatus StreamIn::setHwGain(const std::vector<float>& in_channelGains) {
+    LOG(DEBUG) << __func__ << ": gains " << ::android::internal::ToString(in_channelGains);
+    return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+}
+
 // static
 ndk::ScopedAStatus StreamOut::createInstance(const SourceMetadata& sourceMetadata,
                                              StreamContext context,
@@ -680,4 +691,15 @@
     LOG(DEBUG) << __func__;
 }
 
+ndk::ScopedAStatus StreamOut::getHwVolume(std::vector<float>* _aidl_return) {
+    LOG(DEBUG) << __func__;
+    (void)_aidl_return;
+    return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+}
+
+ndk::ScopedAStatus StreamOut::setHwVolume(const std::vector<float>& in_channelVolumes) {
+    LOG(DEBUG) << __func__ << ": gains " << ::android::internal::ToString(in_channelVolumes);
+    return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+}
+
 }  // namespace aidl::android::hardware::audio::core
diff --git a/audio/aidl/default/include/core-impl/Stream.h b/audio/aidl/default/include/core-impl/Stream.h
index 5746f9d..e8b2c54 100644
--- a/audio/aidl/default/include/core-impl/Stream.h
+++ b/audio/aidl/default/include/core-impl/Stream.h
@@ -305,6 +305,8 @@
         return StreamCommonImpl<::aidl::android::hardware::audio::common::SinkMetadata,
                                 StreamInWorker>::updateMetadata(in_sinkMetadata);
     }
+    ndk::ScopedAStatus getHwGain(std::vector<float>* _aidl_return) override;
+    ndk::ScopedAStatus setHwGain(const std::vector<float>& in_channelGains) override;
 
   public:
     static ndk::ScopedAStatus createInstance(
@@ -337,6 +339,8 @@
         return StreamCommonImpl<::aidl::android::hardware::audio::common::SourceMetadata,
                                 StreamOutWorker>::updateMetadata(in_sourceMetadata);
     }
+    ndk::ScopedAStatus getHwVolume(std::vector<float>* _aidl_return) override;
+    ndk::ScopedAStatus setHwVolume(const std::vector<float>& in_channelVolumes) override;
 
   public:
     static ndk::ScopedAStatus createInstance(
diff --git a/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp b/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
index d21b118..50fb981 100644
--- a/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
+++ b/audio/aidl/vts/VtsHalAudioCoreModuleTargetTest.cpp
@@ -82,6 +82,7 @@
 using aidl::android::media::audio::common::AudioSource;
 using aidl::android::media::audio::common::AudioUsage;
 using aidl::android::media::audio::common::Void;
+using android::hardware::audio::common::getChannelCount;
 using android::hardware::audio::common::isBitPositionFlagSet;
 using android::hardware::audio::common::isTelephonyDeviceType;
 using android::hardware::audio::common::StreamLogic;
@@ -189,6 +190,29 @@
     AudioPortConfig mConfig;
 };
 
+template <typename T>
+void GenerateTestArrays(size_t validElementCount, T validMin, T validMax,
+                        std::vector<std::vector<T>>* validValues,
+                        std::vector<std::vector<T>>* invalidValues) {
+    validValues->emplace_back(validElementCount, validMin);
+    validValues->emplace_back(validElementCount, validMax);
+    validValues->emplace_back(validElementCount, (validMin + validMax) / 2.f);
+    if (validElementCount > 0) {
+        invalidValues->emplace_back(validElementCount - 1, validMin);
+    }
+    invalidValues->emplace_back(validElementCount + 1, validMin);
+    for (auto m : {-2, -1, 2}) {
+        const auto invalidMin = m * validMin;
+        if (invalidMin < validMin || invalidMin > validMax) {
+            invalidValues->emplace_back(validElementCount, invalidMin);
+        }
+        const auto invalidMax = m * validMax;
+        if (invalidMax < validMin || invalidMax > validMax) {
+            invalidValues->emplace_back(validElementCount, invalidMax);
+        }
+    }
+}
+
 template <typename PropType, class Instance, typename Getter, typename Setter>
 void TestAccessors(Instance* inst, Getter getter, Setter setter,
                    const std::vector<PropType>& validValues,
@@ -202,13 +226,14 @@
     ASSERT_TRUE(status.isOk()) << "Unexpected status from a getter: " << status;
     *isSupported = true;
     for (const auto v : validValues) {
-        EXPECT_IS_OK((inst->*setter)(v)) << "for valid value: " << v;
+        EXPECT_IS_OK((inst->*setter)(v)) << "for a valid value: " << ::testing::PrintToString(v);
         PropType currentValue{};
         EXPECT_IS_OK((inst->*getter)(&currentValue));
         EXPECT_EQ(v, currentValue);
     }
     for (const auto v : invalidValues) {
-        EXPECT_STATUS(EX_ILLEGAL_ARGUMENT, (inst->*setter)(v)) << "for invalid value: " << v;
+        EXPECT_STATUS(EX_ILLEGAL_ARGUMENT, (inst->*setter)(v))
+                << "for an invalid value: " << ::testing::PrintToString(v);
     }
     EXPECT_IS_OK((inst->*setter)(initialValue)) << "Failed to restore the initial value";
 }
@@ -2019,6 +2044,42 @@
         }
     }
 
+    void HwGainHwVolume() {
+        const auto ports =
+                moduleConfig->getMixPorts(IOTraits<Stream>::is_input, false /*attachedOnly*/);
+        if (ports.empty()) {
+            GTEST_SKIP() << "No mix ports";
+        }
+        bool atLeastOneSupports = false;
+        for (const auto& port : ports) {
+            const auto portConfig = moduleConfig->getSingleConfigForMixPort(true, port);
+            if (!portConfig.has_value()) continue;
+            WithStream<Stream> stream(portConfig.value());
+            ASSERT_NO_FATAL_FAILURE(stream.SetUp(module.get(), kDefaultBufferSizeFrames));
+            std::vector<std::vector<float>> validValues, invalidValues;
+            bool isSupported = false;
+            if constexpr (IOTraits<Stream>::is_input) {
+                GenerateTestArrays<float>(getChannelCount(portConfig.value().channelMask.value()),
+                                          IStreamIn::HW_GAIN_MIN, IStreamIn::HW_GAIN_MAX,
+                                          &validValues, &invalidValues);
+                EXPECT_NO_FATAL_FAILURE(TestAccessors<std::vector<float>>(
+                        stream.get(), &IStreamIn::getHwGain, &IStreamIn::setHwGain, validValues,
+                        invalidValues, &isSupported));
+            } else {
+                GenerateTestArrays<float>(getChannelCount(portConfig.value().channelMask.value()),
+                                          IStreamOut::HW_VOLUME_MIN, IStreamOut::HW_VOLUME_MAX,
+                                          &validValues, &invalidValues);
+                EXPECT_NO_FATAL_FAILURE(TestAccessors<std::vector<float>>(
+                        stream.get(), &IStreamOut::getHwVolume, &IStreamOut::setHwVolume,
+                        validValues, invalidValues, &isSupported));
+            }
+            if (isSupported) atLeastOneSupports = true;
+        }
+        if (!atLeastOneSupports) {
+            GTEST_SKIP() << "Hardware gain / volume is not supported";
+        }
+    }
+
     void OpenTwiceSamePortConfigImpl(const AudioPortConfig& portConfig) {
         WithStream<Stream> stream1(portConfig);
         ASSERT_NO_FATAL_FAILURE(stream1.SetUp(module.get(), kDefaultBufferSizeFrames));
@@ -2095,6 +2156,7 @@
 TEST_IN_AND_OUT_STREAM(UpdateHwAvSyncId);
 TEST_IN_AND_OUT_STREAM(GetVendorParameters);
 TEST_IN_AND_OUT_STREAM(SetVendorParameters);
+TEST_IN_AND_OUT_STREAM(HwGainHwVolume);
 
 namespace aidl::android::hardware::audio::core {
 std::ostream& operator<<(std::ostream& os, const IStreamIn::MicrophoneDirection& md) {