audio: Add methods for controlling hw volume

Add the following methods:
 - IStreamIn.get/setHwGain;
 - IStreamOut.get/setHwVolume.

Bug: 205884982
Test: atest VtsHalAudioCoreTargetTest
Change-Id: I8fc48c15a9211b5f0bf8bb4b5b0e50d414b859c2
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