一、framework层
1. APP调用 AudioManager 的 adjustStreamVolume() 接口实现在： frameworks\base\services\core\java\com\android\server\audio\AudioService.java
在判断当前是系统静音操作时，调用 HdmiOutAudioMute Native接口：
if (isMuteAdjust) {
boolean state;
if (direction == AudioManager.ADJUST_TOGGLE_MUTE) {
state = !streamState.mIsMuted;
} else {
state = direction == AudioManager.ADJUST_MUTE;
}
if (streamTypeAlias == AudioSystem.STREAM_MUSIC) {
setSystemAudioMute(state);
/*lxl 20191206 add patch begin*/
PowerManagerService.nativeSetHdmiOutAudioMute(state);
/*lxl 20191130 add patch end*/
}
for (int stream = ; stream < mStreamStates.length; stream++) {
if (streamTypeAlias == mStreamVolumeAlias[stream]) {
if (!(readCameraSoundForced()
&& (mStreamStates[stream].getStreamType()
== AudioSystem.STREAM_SYSTEM_ENFORCED))) {
mStreamStates[stream].mute(state);
}
}
}
}2. nativeSetHdmiOutAudioMute 接口声明在： frameworks\base\services\core\java\com\android\server\power\PowerManagerService.java
public static native boolean nativeSetHdmiOutAudioMute(boolean onOff);
二、Native层
1.frameworks\base\services\core\jni\com_android_server_power_PowerManagerService.cpp 中实现了 nativeSetHdmiOutAudioMute() 方法：
static jboolean nativeSetHdmiOutAudioMute(JNIEnv *env, jclass clazz, jboolean onOff){
std::lock_guard<std::mutex> lock(gPowerHalMutex);
if (getInputHal()) {
Return<bool> ret = gInputHal->setHdmiOutAudioMute(onOff);
if (!ret.isOk()) {
ALOGE("Failed to SetHdmiOutAudioMute.");
return false;
}
return ret;
}
ALOGE("Failed to SetHdmiOutAudioMute input hal is null.");
return false;
}Native方法的声明和注册：
static const JNINativeMethod gPowerManagerServiceMethods[] = {
/* name, signature, funcPtr */
......
{"nativeSetHdmiOutAudioMute", "(Z)Z",
(void*) nativeSetHdmiOutAudioMute },
......
}int register_android_server_PowerManagerService(JNIEnv* env) {
int res = jniRegisterNativeMethods(env, "com/android/server/power/PowerManagerService",
gPowerManagerServiceMethods, NELEM(gPowerManagerServiceMethods));
(void) res; // Faked use when LOG_NDEBUG.
LOG_FATAL_IF(res < , "Unable to register native methods.");
// Callbacks
jclass clazz;
FIND_CLASS(clazz, "com/android/server/power/PowerManagerService");
GET_METHOD_ID(gPowerManagerServiceClassInfo.userActivityFromNative, clazz,
"userActivityFromNative", "(JII)V");
// Initialize
for (int i = ; i <= USER_ACTIVITY_EVENT_LAST; i++) {
gLastEventTime[i] = LLONG_MIN;
}
gPowerManagerServiceObj = NULL;
return ;
}2. 上面 gInputHal->setHdmiOutAudioMute(onOff); 调用是通过HIDL调用HAL层接口， Service的获取：
bool getInputHal(){
if (gInputHal == nullptr){
gInputHal = IMstarTvInput::getService();
if (gInputHal == nullptr) {
ALOGD("Load input HAL service fail");
return -;
}
}
return gInputHal != nullptr;
}三、HAL层
1 HIDL接口定义 vendor\mstar\hardware\interfaces\tv\input\1.0\IMstarTvInput.hal，继承于 TvInput ：
interface IMstarTvInput
extends [email protected]::ITvInput {
@callflow(next="*")
//EpgManager function(31/32)
...
setHdmiOutAudioMute(bool bEnable)
generates (bool result);
...
}
2. 接口的定义 vendor\mstar\hardware\interfaces\tv\input\1.0\default\TvInput.h, TvInput 又继承于 IMstarTvInput ：
struct TvInput : public IMstarTvInput {
TvInput(mstar_tv_input_device_t* device);
~TvInput();
/*mstar tv interface*/
...
Return<bool> setHdmiOutAudioMute(bool bEnable);
...
}3. 具体的方法实现在 vendor\mstar\hardware\interfaces\tv\input\1.0\default\TvInput_TvManager.cpp
Return<bool> TvInput::setHdmiOutAudioMute(bool bEnable){
return mDevice->TvManager_dev->setHdmiOutAudioMute(bEnable);
}系统静音的方法实现便在另外文件：vendor\mstar\hardware\interfaces\tv\input\1.0\default\TvInput_AudioManager.cpp
4. 其中 mDevice->TvManager_dev->setHdmiOutAudioMute() 方法的定义在：vendor\mstar\hardware\interfaces\tv\input\1.0\default\mstarTvInput_TvManager_dev.h
#ifndef MSTAR_TV_INPUT_TvManager_H
#define MSTAR_TV_INPUT_TvManager_H
#include <mstar/hardware/tv/input/1.0/ITvManagerType.h>
#include "tvmanager/TvManager.h"
using ::mstar::hardware::tv::input::V1_0::ITvManagerType;
typedef struct mstar_TvManager_dev {
......
bool (*setHdmiOutAudioMute)(bool bEnable);
......
}
5. 其方法实现在 vendor\mstar\hardware\tv_input\mstar_tv_input_TvManager.cpp
bool mstar_tv_input_TvManager::setHdmiOutAudioMute(bool bEnable){
return g_pTvManagerImpl->setHdmiOutAudioMute(bEnable);
}g_pTvManagerImpl 是通过 TvManager 转换所得：
void mstar_tv_input_TvManager::registerTvManagerInstance(sp<TvManager> &ptr) {
g_pTvManagerImpl=ptr;
}6. TvManager 的接口定义在 vendor\mstar\common\libraries\tvapi\hidl_wrapper\tvmanager\TvManager.h
class TvManager : virtual public RefBase
{
public:
TvManager();
~TvManager(); static sp<TvManager> connect();
void HIDLconnect();
static void disconnect(); status_t setListener(const sp<TvManagerListener>& listener); ...
static bool setHdmiOutAudioMute(bool bEnable);
... }
7. 方法实现在 vendor\mstar\supernova\projects\tvos\tvmanager\libtvmanager\TvManager.cpp：
bool TvManager::setHdmiOutAudioMute(bool bOnOff)
{
ALOGV("TvManager setHdmiOutAudioMute\n");
return getITvManager()->setHdmiOutAudioMute(bOnOff);
}
后面就跳跃到 mstar 的 supernova 层。
四、Supernova层
1. TvManager 的 setHdmiOutAudioMute 实现在 vendor\mstar\supernova\projects\tvos\tvmanager\libtvmanagerservice\
bool TvManagerService::Client::setHdmiOutAudioMute(bool bOnOff){
TVOS_API_ESTIMATE_START()
TVOS_API_ESTIMATE_START(LOCK)
Mutex::Autolock lock(m_FuncLock);
TVOS_API_ESTIMATE_END(LOCK)
ALOGV("TvManagerService::Client::setHdmiOutAudioMute\n");
bool ret = FALSE;
ret = MSrv_Control::GetInstance()->setHdmiOutAudioMute(bOnOff);
TVOS_API_ESTIMATE_END()
return ret;
}2. 最终方法实现在vendor\mstar\supernova\projects\tvos\tvmanager\libtvmanagerservice\TvManagerService.cpp，后面便是通过I2C接口对HDMI控制器的操作。
bool TvManagerService::Client::setHdmiOutAudioMute(bool bOnOff){
TVOS_API_ESTIMATE_START()
TVOS_API_ESTIMATE_START(LOCK)
Mutex::Autolock lock(m_FuncLock);
TVOS_API_ESTIMATE_END(LOCK)
ALOGV("TvManagerService::Client::setHdmiOutAudioMute\n");
bool ret = FALSE;
ret = MSrv_Control::GetInstance()->setHdmiOutAudioMute(bOnOff);
TVOS_API_ESTIMATE_END()
return ret;
}