记录一下AudioPolicy初始化过程。
frameworks\av\media\audioserver\audioserver.rc
service audioserver /system/bin/audioserver
class main
user audioserver
# media gid needed for /dev/fm (radio) and for /data/misc/media (tee)
group audio camera drmrpc inet media mediadrm net_bt net_bt_admin net_bw_acct oem_2901
ioprio rt 4
writepid /dev/cpuset/foreground/tasks /dev/stune/foreground/tasks
onrestart restart audio-hal-2-0
frameworks\av\media\audioserver\main_audioserver.cpp
int main(int argc __unused, char **argv)
AudioFlinger::instantiate();
AudioPolicyService::instantiate();
frameworks\av\services\audiopolicy\service\AudioPolicyService.cpp
void AudioPolicyService::onFirstRef()
{
{
Mutex::Autolock _l(mLock);
// start tone playback thread
mTonePlaybackThread = new AudioCommandThread(String8("ApmTone"), this);
// start audio commands thread
mAudioCommandThread = new AudioCommandThread(String8("ApmAudio"), this);
// start output activity command thread
mOutputCommandThread = new AudioCommandThread(String8("ApmOutput"), this);
mAudioPolicyClient = new AudioPolicyClient(this);
mAudioPolicyManager = createAudioPolicyManager(mAudioPolicyClient); // 创建AudioPolicyManager
}
// load audio processing modules
spaudioPolicyEffects = new AudioPolicyEffects(); // 加载声音效果文件
{
Mutex::Autolock _l(mLock);
mAudioPolicyEffects = audioPolicyEffects;
}
}
// 加载声音效果
AudioPolicyEffects::AudioPolicyEffects()
{
status_t loadResult = loadAudioEffectXmlConfig();
if (loadResult < 0) {
ALOGW("Failed to load XML effect configuration, fallback to .conf");
// load automatic audio effect modules
if (access(AUDIO_EFFECT_VENDOR_CONFIG_FILE, R_OK) == 0) {
loadAudioEffectConfig(AUDIO_EFFECT_VENDOR_CONFIG_FILE);
} else if (access(AUDIO_EFFECT_DEFAULT_CONFIG_FILE, R_OK) == 0) {
loadAudioEffectConfig(AUDIO_EFFECT_DEFAULT_CONFIG_FILE);
}
} else if (loadResult > 0) {
ALOGE("Effect config is partially invalid, skipped %d elements", loadResult);
}
}
system\media\audio\include\system\audio_effects\audio_effects_conf.h
#define AUDIO_EFFECT_DEFAULT_CONFIG_FILE "/system/etc/audio_effects.conf"
#define AUDIO_EFFECT_VENDOR_CONFIG_FILE "/vendor/etc/audio_effects.conf"
frameworks\av\services\audiopolicy\manager\AudioPolicyFactory.cpp
extern "C" AudioPolicyInterface* createAudioPolicyManager(
AudioPolicyClientInterface *clientInterface)
{
return new AudioPolicyManager(clientInterface);
}
AudioPolicyManager创建：
初始化主要读取xml文件，获取可以支持的设备类型，采样率等参数。
frameworks\av\services\audiopolicy\managerdefault\AudioPolicyManager.cpp
AudioPolicyManager::AudioPolicyManager(AudioPolicyClientInterface *clientInterface)
:
#ifdef AUDIO_POLICY_TEST
Thread(false),
#endif //AUDIO_POLICY_TEST
mLimitRingtoneVolume(false), mLastVoiceVolume(-1.0f),
mA2dpSuspended(false),
mAudioPortGeneration(1),
mBeaconMuteRefCount(0),
mBeaconPlayingRefCount(0),
mBeaconMuted(false),
mTtsOutputAvailable(false),
mMasterMono(false),
mMusicEffectOutput(AUDIO_IO_HANDLE_NONE),
mHasComputedSoundTriggerSupportsConcurrentCapture(false)
{
mUidCached = getuid();
mpClientInterface = clientInterface;
// TODO: remove when legacy conf file is removed. true on devices that use DRC on the
// DEVICE_CATEGORY_SPEAKER path to boost soft sounds, used to adjust volume curves accordingly.
// Note: remove also speaker_drc_enabled from global configuration of XML config file.
bool speakerDrcEnabled = false;
//hardware\qcom\audio\configs\msm8953\msm8953.mk
//USE_XML_AUDIO_POLICY_CONF := 1
#ifdef USE_XML_AUDIO_POLICY_CONF
// 设置声音曲线
mVolumeCurves = new VolumeCurvesCollection();
AudioPolicyConfig config(mHwModules, mAvailableOutputDevices, mAvailableInputDevices,
mDefaultOutputDevice, speakerDrcEnabled,
static_cast(mVolumeCurves));
// 解析文件audio_policy_configuration.xml
if (deserializeAudioPolicyXmlConfig(config) != NO_ERROR) {
#else
mVolumeCurves = new StreamDescriptorCollection();
AudioPolicyConfig config(mHwModules, mAvailableOutputDevices, mAvailableInputDevices,
mDefaultOutputDevice, speakerDrcEnabled);
// #define AUDIO_POLICY_CONFIG_FILE "/system/etc/audio_policy.conf"
// #define AUDIO_POLICY_VENDOR_CONFIG_FILE "/vendor/etc/audio_policy.conf"
if ((ConfigParsingUtils::loadConfig(AUDIO_POLICY_VENDOR_CONFIG_FILE, config) != NO_ERROR) &&
(ConfigParsingUtils::loadConfig(AUDIO_POLICY_CONFIG_FILE, config) != NO_ERROR)) {
#endif
ALOGE("could not load audio policy configuration file, setting defaults");
config.setDefault();
}
// must be done after reading the policy (since conditionned by Speaker Drc Enabling)
mVolumeCurves->initializeVolumeCurves(speakerDrcEnabled);
// Once policy config has been parsed, retrieve an instance of the engine and initialize it.
audio_policy::EngineInstance *engineInstance = audio_policy::EngineInstance::getInstance();
if (!engineInstance) {
ALOGE("%s: Could not get an instance of policy engine", __FUNCTION__);
return;
}
// Retrieve the Policy Manager Interface
mEngine = engineInstance->queryInterface();
if (mEngine == NULL) {
ALOGE("%s: Failed to get Policy Engine Interface", __FUNCTION__);
return;
}
mEngine->setObserver(this);
status_t status = mEngine->initCheck();
(void) status;
ALOG_ASSERT(status == NO_ERROR, "Policy engine not initialized(err=%d)", status);
// mAvailableOutputDevices and mAvailableInputDevices now contain all attached devices
// open all output streams needed to access attached devices
audio_devices_t outputDeviceTypes = mAvailableOutputDevices.types();
audio_devices_t inputDeviceTypes = mAvailableInputDevices.types() & ~AUDIO_DEVICE_BIT_IN;
for (size_t i = 0; i < mHwModules.size(); i++) {
mHwModules[i]->mHandle = mpClientInterface->loadHwModule(mHwModules[i]->getName());
ALOGE("Liutao %s: mHwModules.name: %s", __FUNCTION__, mHwModules[i]->getName());
/*
打印出的模块名 // 对应xml的mudule.
AudioPolicyManager: mHwModules.name: primary
AudioPolicyManager: mHwModules.name: a2dp
AudioPolicyManager: mHwModules.name: usb
AudioPolicyManager: mHwModules.name: r_submix
*/
if (mHwModules[i]->mHandle == 0) {
ALOGW("could not open HW module %s", mHwModules[i]->getName());
continue;
}
// open all output streams needed to access attached devices
// except for direct output streams that are only opened when they are actually
// required by an app.
// This also validates mAvailableOutputDevices list
// 对应xml的profile
for (size_t j = 0; j < mHwModules[i]->mOutputProfiles.size(); j++)
{
const sp outProfile = mHwModules[i]->mOutputProfiles[j];
// ALOGE("Liutao %s: mOutputProfile.name: %s", __FUNCTION__, mHwModules[i]->mOutputProfiles.getName());
if (!outProfile->hasSupportedDevices()) {
ALOGW("Output profile contains no device on module %s", mHwModules[i]->getName());
continue;
}
if ((outProfile->getFlags() & AUDIO_OUTPUT_FLAG_TTS) != 0) {
mTtsOutputAvailable = true;
}
if ((outProfile->getFlags() & AUDIO_OUTPUT_FLAG_DIRECT) != 0) {
continue;
}
audio_devices_t profileType = outProfile->getSupportedDevicesType();
if ((profileType & mDefaultOutputDevice->type()) != AUDIO_DEVICE_NONE) {
profileType = mDefaultOutputDevice->type();
} else {
// chose first device present in profile's SupportedDevices also part of
// outputDeviceTypes
profileType = outProfile->getSupportedDeviceForType(outputDeviceTypes);
}
if ((profileType & outputDeviceTypes) == 0) {
continue;
}
sp outputDesc = new SwAudioOutputDescriptor(outProfile,
mpClientInterface);
const DeviceVector &supportedDevices = outProfile->getSupportedDevices();
const DeviceVector &devicesForType = supportedDevices.getDevicesFromType(profileType);
String8 address = devicesForType.size() > 0 ? devicesForType.itemAt(0)->mAddress
: String8("");
outputDesc->mDevice = profileType;
audio_config_t config = AUDIO_CONFIG_INITIALIZER;
config.sample_rate = outputDesc->mSamplingRate;
config.channel_mask = outputDesc->mChannelMask;
config.format = outputDesc->mFormat;
audio_io_handle_t output = AUDIO_IO_HANDLE_NONE;
status_t status = mpClientInterface->openOutput(outProfile->getModuleHandle(),
&output,
&config,
&outputDesc->mDevice,
address,
&outputDesc->mLatency,
outputDesc->mFlags);
if (status != NO_ERROR) {
ALOGW("Cannot open output stream for device %08x on hw module %s",
outputDesc->mDevice,
mHwModules[i]->getName());
} else {
outputDesc->mSamplingRate = config.sample_rate;
outputDesc->mChannelMask = config.channel_mask;
outputDesc->mFormat = config.format;
for (size_t k = 0; k < supportedDevices.size(); k++) {
ssize_t index = mAvailableOutputDevices.indexOf(supportedDevices[k]);
// give a valid ID to an attached device once confirmed it is reachable
if (index >= 0 && !mAvailableOutputDevices[index]->isAttached()) {
mAvailableOutputDevices[index]->attach(mHwModules[i]);
}
}
if (mPrimaryOutput == 0 &&
outProfile->getFlags() & AUDIO_OUTPUT_FLAG_PRIMARY) {
mPrimaryOutput = outputDesc;
}
addOutput(output, outputDesc);
setOutputDevice(outputDesc,
outputDesc->mDevice,
true,
0,
NULL,
address.string());
}
}
...
// config文件解析
#define AUDIO_POLICY_XML_CONFIG_FILE_PATH_MAX_LENGTH 128
#define AUDIO_POLICY_XML_CONFIG_FILE_NAME "audio_policy_configuration.xml"
#ifdef USE_XML_AUDIO_POLICY_CONF
// Treblized audio policy xml config will be located in /odm/etc or /vendor/etc.
static const char *kConfigLocationList[] =
{"/odm/etc", "/vendor/etc/audio", "/vendor/etc", "/system/etc"};
static const int kConfigLocationListSize =
(sizeof(kConfigLocationList) / sizeof(kConfigLocationList[0]));
static status_t deserializeAudioPolicyXmlConfig(AudioPolicyConfig &config) {
char audioPolicyXmlConfigFile[AUDIO_POLICY_XML_CONFIG_FILE_PATH_MAX_LENGTH];
status_t ret;
for (int i = 0; i < kConfigLocationListSize; i++) {
PolicySerializer serializer;
snprintf(audioPolicyXmlConfigFile,
sizeof(audioPolicyXmlConfigFile),
"%s/%s",
kConfigLocationList[i],
AUDIO_POLICY_XML_CONFIG_FILE_NAME);
ret = serializer.deserialize(audioPolicyXmlConfigFile, config);
if (ret == NO_ERROR) {
break;
}
}
return ret;
}
#endif
audio_policy_configuration.xml文件
- Earpiece
- Speaker
- Telephony Tx
- Built-In Mic
- Built-In Back Mic
- FM Tuner
- Telephony Rx
Speaker
Shenzhen，2018-8-30