Use top mic by default, default top mic

vendor/mediatek/proprietary/hardware/audio/common/V3/aud_drv/AudioALSAHardware.cpp

source code

if (param.getInt(keySET_MIC_CHOOSE, value) ==NO_ERROR) {
       param.remove(keySET_MIC_CHOOSE);
       ALOGD("+%s(): %s", __FUNCTION__,"setBuiltInMicSpecificType");
       if(value==2){
           AudioALSAHardwareResourceManager::getInstance()->setBuiltInMicSpecificType(BUILTIN_MIC_MIC2_ONLY);
       }else if(value==1){
           AudioALSAHardwareResourceManager::getInstance()->setBuiltInMicSpecificType(BUILTIN_MIC_MIC1_ONLY);
       }else{
           AudioALSAHardwareResourceManager::getInstance()->setBuiltInMicSpecificType(BUILTIN_MIC_DEFAULT);
       }
    }

Change this else to mic2, which is the top microphone

AudioALSAHardwareResourceManager::getInstance()->setBuiltInMicSpecificType(BUILTIN_MIC_MIC2_ONLY);

Then wherever you can receive the boot broadcast or in finshbooting in the AcitivityManagerService just after boot, set the value to 0 and let it go to else:

For example ./override/vendor/mediatek/proprietary/packages/apps/MtkSettings/src/com/mediatek/settings/network/RoamingSettingsReceiver.java

Static broadcast acceptance. This has the action of receiving the boot broadcast

join in

import android.media.AudioManager;
 
AudioManager mAudioManager = (AudioManager) sContext.getSystemService(Context.AUDIO_SERVICE);
       mAudioManager.setParameters("ForceUseSpecificMic=0");

The string written by this parameter, why use this,

in AudioALSAHardware.cpp

here is

if(param.getInt(keySET_MIC_CHOOSE, value) == NO_ERROR) {

This defines

//Dual Mic use only one mic

static String8 keySET_MIC_CHOOSE =String8("ForceUseSpecificMic");