Helio A22
/dev/snd
pcmC0D10p pcmC0D14p pcmC0D17p pcmC0D1c pcmC0D23p pcmC0D26c pcmC0D28p pcmC0D30c pcmC0D32c pcmC0D5c pcmC0D7p sequencer pcmC0D11p pcmC0D15c pcmC0D18c pcmC0D20p pcmC0D24p pcmC0D26p pcmC0D29p pcmC0D30p pcmC0D3c pcmC0D5p pcmC0D8p sequencer2 controlC0 pcmC0D12c pcmC0D16c pcmC0D18p pcmC0D21p pcmC0D25c pcmC0D27c pcmC0D2c pcmC0D31c pcmC0D3p pcmC0D6c pcmC0D9c timer pcmC0D0p pcmC0D13c pcmC0D17c pcmC0D19p pcmC0D22c pcmC0D25p pcmC0D28c pcmC0D2p pcmC0D31p pcmC0D4p pcmC0D6p seq
/vendor/lib/hw/audio.primary.mt6765.so
setBGSDlMute
setBGSUlMute
platform/common/hardware/audio/V3/aud_drv/AudioALSAHardware.cpp
...
// Set BGS Mute
static String8 keySet_BGS_DL_Mute = String8("Set_BGS_DL_Mute");
static String8 keySet_BGS_UL_Mute = String8("Set_BGS_UL_Mute");
// Set Phone Call Mute
static String8 keySet_SpeechCall_DL_Mute = String8("Set_SpeechCall_DL_Mute");
static String8 keySet_SpeechCall_UL_Mute = String8("Set_SpeechCall_UL_Mute");
...
// Set BGS DL Mute (true) / Unmute(false)
if (param.getInt(keySet_BGS_DL_Mute, value) == NO_ERROR)
{
param.remove(keySet_BGS_DL_Mute);
ALOGD("%s(), %s", __FUNCTION__, keyValuePairs.string());
mStreamManager->setBGSDlMute((bool)value);
}
// Set BGS UL Mute (true) / Unmute(false)
if (param.getInt(keySet_BGS_UL_Mute, value) == NO_ERROR)
{
param.remove(keySet_BGS_UL_Mute);
ALOGD("%s(), %s", __FUNCTION__, keyValuePairs.string());
mStreamManager->setBGSUlMute((bool)value);
}
// Set SpeechCall DL Mute (true) / Unmute(false)
if (param.getInt(keySet_SpeechCall_DL_Mute, value) == NO_ERROR)
{
param.remove(keySet_SpeechCall_DL_Mute);
ALOGD("%s(), %s", __FUNCTION__, keyValuePairs.string());
mSpeechPhoneCallController->setDlMute((bool)value);
}
// Set SpeechCall UL Mute (true) / Unmute(false)
if (param.getInt(keySet_SpeechCall_UL_Mute, value) == NO_ERROR)
{
param.remove(keySet_SpeechCall_UL_Mute);
ALOGD("%s(), %s", __FUNCTION__, keyValuePairs.string());
mSpeechPhoneCallController->setUlMute((bool)value);
}
platform/mt6735/hardware/audio/aud_drv/AudioALSAStreamOut.cpp
开启通话背景音：
Set_BGS_UL_Mute=0 关闭背景音上行的静音, 也就是让对方能听到
Set_SpeechCall_UL_Mute=1 打开mic上行的静音， 也就是让对方听不到这边mic的声音
Set_BGS_DL_Mute=1 开启背景音下行静音， 让自己听不到背景音
platform/mt6735/hardware/audio/aud_drv/AudioALSAStreamManager.cpp
AudioALSAStreamManager::AudioALSAStreamManager() :
mStreamOutIndex(0),
mStreamInIndex(0),
mPlaybackHandlerIndex(0),
mCaptureHandlerIndex(0),
mSpeechPhoneCallController(AudioALSASpeechPhoneCallController::getInstance()),
mFMController(AudioALSAFMController::getInstance()),
mAudioALSAVolumeController(AudioVolumeFactory::CreateAudioVolumeController()),
mSpeechDriverFactory(SpeechDriverFactory::GetInstance()),
mAudioSpeechEnhanceInfoInstance(AudioSpeechEnhanceInfo::getInstance()),
mMicMute(false),
mAudioMode(AUDIO_MODE_NORMAL),
mFilterManagerNumber(0),
mBesLoudnessStatus(false),
mBesLoudnessControlCallback(NULL),
//#ifdef MTK_VOW_SUPPORT
mAudioALSAVoiceWakeUpController(AudioALSAVoiceWakeUpController::getInstance()),
//#endif
mVoiceWakeUpNeedOn(false),
mForceDisableVoiceWakeUpForSetMode(false),
mBypassPostProcessDL(false),
mHeadsetChange(false),
mBGSDlGain(0xFF),
mBGSUlGain(0),
mBypassDualMICProcessUL(false)
{
....
mBGSDlGain 下行增益， 影响到 自己这边听到的声音大小， 最大值是0xFF(256),
mBGSUlGain 上行增益， 影响到 对方听到的声音大小， 最小值是0
所以，默认设置是 自己听得到， 对方听不到
status_t AudioALSAStreamManager::setBGSDlMute(const bool mute_on)
{
if (mute_on)
{
mBGSDlGain = 0;
}
else
{
mBGSDlGain = 0xFF;
}
ALOGD("%s(), mute_on: %d, mBGSDlGain=0x%x", __FUNCTION__, mute_on, mBGSDlGain);
return NO_ERROR;
}
．．．
status_t AudioALSAStreamManager::setBGSUlMute(const bool mute_on)
{
if (mute_on)
{
mBGSUlGain = 0;
}
else
{
mBGSUlGain = 0xFF;
}
ALOGD("%s(), mute_on: %d, mBGSUlGain=0x%x", __FUNCTION__, mute_on, mBGSUlGain);
return NO_ERROR;
}
可以通过 setBGSDlMute 函数来设置 mBGSDlGain变量的大小
hardware/audio/speech_driver/AudioALSASpeechPhoneCallController.cpp
void AudioALSASpeechPhoneCallController::setDlMute(const bool mute_on)
{
ALOGD("%s(), new mute_on = %d, old mDlMute = %d", __FUNCTION__, mute_on, mDlMute);
AudioAutoTimeoutLock _l(mLock);
mSpeechDriverFactory->GetSpeechDriver()->SetDownlinkMute(mute_on);
property_set(PROPERTY_KEY_DL_MUTE_ON, (mute_on == false) ? "0" : "1");
mDlMute = mute_on;
}
void AudioALSASpeechPhoneCallController::setUlMute(const bool mute_on)
{
ALOGD("+%s(), new mute_on = %d, old mULMute = %d", __FUNCTION__, mute_on, mUlMute);
AudioAutoTimeoutLock _l(mLock);
mSpeechDriverFactory->GetSpeechDriver()->SetUplinkSourceMute(mute_on);
property_set(PROPERTY_KEY_UL_MUTE_ON, (mute_on == false) ? "0" : "1");
mUlMute = mute_on;
}
platform/common/hardware/audio/V3/aud_drv/AudioALSAPlaybackHandlerVoice.cpp
...
status_t AudioALSAPlaybackHandlerVoice::open()
{
ALOGD("+%s(), audio_mode = %d, u8BGSUlGain = %d, u8BGSDlGain = %d", __FUNCTION__, mStreamAttributeSource->audio_mode, mStreamAttributeSource->u8BGSUlGain, mStreamAttributeSource->u8BGSDlGain);
ALOGD("%s() mStreamAttributeSource->audio_format =%d", __FUNCTION__,mStreamAttributeSource->audio_format);
// debug pcm dump
OpenPCMDump(LOG_TAG);
// HW attribute config // TODO(Harvey): query this
mStreamAttributeTarget.audio_format = AUDIO_FORMAT_PCM_16_BIT;
mStreamAttributeTarget.audio_channel_mask = mStreamAttributeSource->audio_channel_mask; // same as source stream
mStreamAttributeTarget.num_channels = android_audio_legacy::AudioSystem::popCount(mStreamAttributeTarget.audio_channel_mask);
mStreamAttributeTarget.sample_rate = ChooseTargetSampleRate(mStreamAttributeSource->sample_rate); // same as source stream
ALOGD("mStreamAttributeTarget sample_rate = %d mStreamAttributeSource sample_rate = %d",mStreamAttributeTarget.sample_rate,mStreamAttributeSource->sample_rate);
mStreamAttributeTarget.u8BGSDlGain = mStreamAttributeSource->u8BGSDlGain;
mStreamAttributeTarget.u8BGSUlGain = mStreamAttributeSource->u8BGSUlGain;
// bit conversion
initBitConverter();
// open background sound
mBGSPlayer->mBGSMutex.lock();
if (mStreamAttributeTarget.num_channels > 2)
{
mBGSPlayer->CreateBGSPlayBuffer(
mStreamAttributeTarget.sample_rate,
2,
mStreamAttributeTarget.audio_format);
}
else
{
mBGSPlayer->CreateBGSPlayBuffer(
mStreamAttributeTarget.sample_rate,
mStreamAttributeTarget.num_channels,
mStreamAttributeTarget.audio_format);
}
mBGSPlayer->Open(SpeechDriverFactory::GetInstance()->GetSpeechDriver(), mStreamAttributeTarget.u8BGSUlGain, mStreamAttributeTarget.u8BGSDlGain);
mBGSPlayer->mBGSMutex.unlock();
ALOGD("-%s()", __FUNCTION__);
return NO_ERROR;
}
....
可以看到 上下行增益 怎么传递过来的