Implement volume control on default audio HAL
Implemented volume control based on setting audio port config.
Bug: 336370745
Test: atest VtsHalAudioCoreTargetTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:122597a5e96c873239540a53523caf67fe806d90)
Merged-In: Ia590974e61aa3a1c3f70afdb54ce87c85e9a1b3c
Change-Id: Ia590974e61aa3a1c3f70afdb54ce87c85e9a1b3c
diff --git a/audio/aidl/default/alsa/Utils.cpp b/audio/aidl/default/alsa/Utils.cpp
index 8eaf162..10374f2 100644
--- a/audio/aidl/default/alsa/Utils.cpp
+++ b/audio/aidl/default/alsa/Utils.cpp
@@ -22,6 +22,8 @@
#include <aidl/android/media/audio/common/AudioFormatType.h>
#include <aidl/android/media/audio/common/PcmType.h>
#include <android-base/logging.h>
+#include <audio_utils/primitives.h>
+#include <cutils/compiler.h>
#include "Utils.h"
#include "core-impl/utils.h"
@@ -343,4 +345,68 @@
return findValueOrDefault(getAudioFormatDescriptorToPcmFormatMap(), aidl, PCM_FORMAT_INVALID);
}
+void applyGain(void* buffer, float gain, size_t bytesToTransfer, enum pcm_format pcmFormat,
+ int channelCount) {
+ if (channelCount != 1 && channelCount != 2) {
+ LOG(WARNING) << __func__ << ": unsupported channel count " << channelCount;
+ return;
+ }
+ if (!getPcmFormatToAudioFormatDescMap().contains(pcmFormat)) {
+ LOG(WARNING) << __func__ << ": unsupported pcm format " << pcmFormat;
+ return;
+ }
+ const float unityGainFloat = 1.0f;
+ if (std::abs(gain - unityGainFloat) < 1e-6) {
+ return;
+ }
+ int numFrames;
+ switch (pcmFormat) {
+ case PCM_FORMAT_S16_LE: {
+ const uint16_t unityGainQ4_12 = u4_12_from_float(unityGainFloat);
+ const uint16_t vl = u4_12_from_float(gain);
+ const uint32_t vrl = (vl << 16) | vl;
+ if (channelCount == 2) {
+ numFrames = bytesToTransfer / sizeof(uint32_t);
+ uint32_t* intBuffer = (uint32_t*)buffer;
+ if (CC_UNLIKELY(vl > unityGainQ4_12)) {
+ // volume is boosted, so we might need to clamp even though
+ // we process only one track.
+ do {
+ int32_t l = mulRL(1, *intBuffer, vrl) >> 12;
+ int32_t r = mulRL(0, *intBuffer, vrl) >> 12;
+ l = clamp16(l);
+ r = clamp16(r);
+ *intBuffer++ = (r << 16) | (l & 0xFFFF);
+ } while (--numFrames);
+ } else {
+ do {
+ int32_t l = mulRL(1, *intBuffer, vrl) >> 12;
+ int32_t r = mulRL(0, *intBuffer, vrl) >> 12;
+ *intBuffer++ = (r << 16) | (l & 0xFFFF);
+ } while (--numFrames);
+ }
+ } else {
+ numFrames = bytesToTransfer / sizeof(uint16_t);
+ int16_t* intBuffer = (int16_t*)buffer;
+ if (CC_UNLIKELY(vl > unityGainQ4_12)) {
+ // volume is boosted, so we might need to clamp even though
+ // we process only one track.
+ do {
+ int32_t mono = mulRL(1, *intBuffer, vrl) >> 12;
+ *intBuffer++ = clamp16(mono);
+ } while (--numFrames);
+ } else {
+ do {
+ int32_t mono = mulRL(1, *intBuffer, vrl) >> 12;
+ *intBuffer++ = static_cast<int16_t>(mono & 0xFFFF);
+ } while (--numFrames);
+ }
+ }
+ } break;
+ default:
+ // TODO(336370745): Implement gain for other supported formats
+ break;
+ }
+}
+
} // namespace aidl::android::hardware::audio::core::alsa