SystemServer.java中：
private void startOtherServices() {
// ...
traceBeginAndSlog("StartWiredAccessoryManager");
try {
// Listen for wired headset changes
inputManager.setWiredAccessoryCallbacks(
new WiredAccessoryManager(context, inputManager));//設定WiredAccessoryCallbacks
} catch (Throwable e) {
reportWtf("starting WiredAccessoryManager", e);
}
// ...
final InputManagerService inputManagerF = inputManager;
// ...
try {
// TODO(BT) Pass parameter to input manager
if (inputManagerF != null) inputManagerF.systemRunning();//調用systemRunning，這裡先記下，下面會看到用途
} catch (Throwable e) {
reportWtf("Notifying InputManagerService running", e);
}
}
先看WiredAccessoryManager對象的建立過程：
WiredAccessoryManager.java中：
構造函數：
public WiredAccessoryManager(Context context, InputManagerService inputManager) {
mContext = context;
PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "WiredAccessoryManager");
mWakeLock.setReferenceCounted(false);
mAudioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);
mInputManager = inputManager;
mUseDevInputEventForAudioJack =
context.getResources().getBoolean(R.bool.config_useDevInputEventForAudioJack);//這裡在config檔案中配置，這裡為false。
mObserver = new WiredAccessoryObserver();//建立WiredAccessoryObserver對象
IntentFilter filter = new IntentFilter(Intent.ACTION_BOOT_COMPLETED);//并且添加了開機廣播接收
filter.addAction("android.intent.action.LAUNCH_POWEROFF_ALARM");
}
看下接收開機廣播幹嘛：但是發現并沒有相關處理。
那麼看下WiredAccessoryObserver()建立時幹了什麼：
WiredAccessoryObserver是WiredAccessoryManager的内部類
public WiredAccessoryObserver() {
mUEventInfo = makeObservedUEventList();//繼續往下看
}
private List<UEventInfo> makeObservedUEventList() { //看起來就是用來擷取要監聽的UEvent
List<UEventInfo> retVal = new ArrayList<UEventInfo>();
UEventInfo uei;
// Monitor h2w
if (!mUseDevInputEventForAudioJack) {//這裡是配置的mUseDevInputEventForAudioJack是false，是以監聽h2w的UEvent事件了，如果是true，就不監聽h2w的UEvent事件了。
uei = new UEventInfo(NAME_H2W, BIT_HEADSET, BIT_HEADSET_NO_MIC, BIT_LINEOUT);//這裡就是一些耳機類型。其對應的UEvent資訊建立在UEventInfo中。
if (uei.checkSwitchExists()) {
retVal.add(uei);
} else {
Slog.w(TAG, "This kernel does not have wired headset support");
}
}
// Monitor USB
uei = new UEventInfo(NAME_USB_AUDIO, BIT_USB_HEADSET_ANLG, BIT_USB_HEADSET_DGTL, );
if (uei.checkSwitchExists()) {
retVal.add(uei);
} else {
Slog.w(TAG, "This kernel does not have usb audio support");
}
// Monitor HDMI
//
// If the kernel has support for the "hdmi_audio" switch, use that. It will be
// signalled only when the HDMI driver has a video mode configured, and the downstream
// sink indicates support for audio in its EDID.
//
// If the kernel does not have an "hdmi_audio" switch, just fall back on the older
// "hdmi" switch instead.
uei = new UEventInfo(NAME_HDMI_AUDIO, BIT_HDMI_AUDIO, , );
if (uei.checkSwitchExists()) {
retVal.add(uei);
} else {
uei = new UEventInfo(NAME_HDMI, BIT_HDMI_AUDIO, , );
if (uei.checkSwitchExists()) {
retVal.add(uei);
} else {
Slog.w(TAG, "This kernel does not have HDMI audio support");
}
}
return retVal;
}
下面看下UEventInfo：也是WiredAccessoryManager的内部類，裡面指出了監聽的節點。getDevPath()與getSwitchStatePath()。
private final class UEventInfo {
private final String mDevName;
private final int mState1Bits;
private final int mState2Bits;
private final int mStateNbits;
public UEventInfo(String devName, int state1Bits, int state2Bits, int stateNbits) {
mDevName = devName;
mState1Bits = state1Bits;
mState2Bits = state2Bits;
mStateNbits = stateNbits;
}
public String getDevName() { return mDevName; }
public String getDevPath() {
return String.format(Locale.US, "/devices/virtual/switch/%s", mDevName);
}
public String getSwitchStatePath() {
return String.format(Locale.US, "/sys/class/switch/%s/state", mDevName);//UEvent事件狀态切換資訊儲存在該節點中。
}
public boolean checkSwitchExists() {
File f = new File(getSwitchStatePath());
return f.exists();
}
public int computeNewHeadsetState(int headsetState, int switchState) {//UEvent事件觸發時執行，修改音頻設定參數。
int preserveMask = ~(mState1Bits | mState2Bits | mStateNbits);
int setBits = ((switchState == ) ? mState1Bits :
((switchState == ) ? mState2Bits :
((switchState == mStateNbits) ? mStateNbits : )));
if (switchState == ) {
num_hs_pole = "num_hs_pole=5";//這裡參數代表的含義是什麼？
setBits = mState1Bits;
} else if (switchState == ) {
num_hs_pole = "num_hs_pole=4";//這裡參數代表的含義是什麼？
} else {
num_hs_pole = "NA";
}
return ((headsetState & preserveMask) | setBits);
}
}
}
現在這個WiredAccessoryObserver是建立了，那它是什麼啟動監聽的呢？
我們已經看完了WiredAccessoryManager對象的建立過程
再看setWiredAccessoryCallbacks過程，看看是不是在這個過程中啟動的監聽：
在InputManagerService.java中：
public void setWiredAccessoryCallbacks(WiredAccessoryCallbacks callbacks) {
mWiredAccessoryCallbacks = callbacks;//就是這麼一句，僅僅是賦個值。那就看下mWiredAccessoryCallbacks用到了哪裡？
}
搜了一下：
第一處：
// Native callback.
//這裡是一個private的方法，外部是沒法調用的，在類中也沒有調用該方法的地方，那這個Native callback是什麼意思？native層可以回調到這個方法？
private void notifySwitch(long whenNanos, int switchValues, int switchMask) {
if (DEBUG) {
Slog.d(TAG, "notifySwitch: values=" + Integer.toHexString(switchValues)
+ ", mask=" + Integer.toHexString(switchMask));
}
Log.d("qdd", "notifySwitch: values=" + Integer.toHexString(switchValues)
+ ", mask=" + Integer.toHexString(switchMask));
if ((switchMask & SW_LID_BIT) != ) {
final boolean lidOpen = ((switchValues & SW_LID_BIT) == );
mWindowManagerCallbacks.notifyLidSwitchChanged(whenNanos, lidOpen);
}
if ((switchMask & SW_CAMERA_LENS_COVER_BIT) != ) {
final boolean lensCovered = ((switchValues & SW_CAMERA_LENS_COVER_BIT) != );
mWindowManagerCallbacks.notifyCameraLensCoverSwitchChanged(whenNanos, lensCovered);
}
if (mUseDevInputEventForAudioJack && (switchMask & SW_JACK_BITS) != ) {
Log.d("qdd", "notifySwitch: notifyWiredAccessoryChanged");
//這裡回調notifyWiredAccessoryChanged方法，進去看下這個方法是幹嘛的？是處理耳機狀态改變的。而且config中配置mUseDevInputEventForAudioJack為false。
mWiredAccessoryCallbacks.notifyWiredAccessoryChanged(whenNanos, switchValues,switchMask);
}
if ((switchMask & SW_TABLET_MODE_BIT) != ) {
SomeArgs args = SomeArgs.obtain();
args.argi1 = (int) (whenNanos & );
args.argi2 = (int) (whenNanos >> );
args.arg1 = Boolean.valueOf((switchValues & SW_TABLET_MODE_BIT) != );
mHandler.obtainMessage(MSG_DELIVER_TABLET_MODE_CHANGED,args).sendToTarget();
}
}
第二處：
public void systemRunning() {//這個就是上面systemserver中設定完WiredAccessoryCallbacks後調用的。
if (DEBUG) {
Slog.d(TAG, "System ready.");
}
mNotificationManager = (NotificationManager)mContext.getSystemService(Context.NOTIFICATION_SERVICE);
mSystemReady = true;
IntentFilter filter = new IntentFilter(Intent.ACTION_PACKAGE_ADDED);
filter.addAction(Intent.ACTION_PACKAGE_REMOVED);
filter.addAction(Intent.ACTION_PACKAGE_CHANGED);
filter.addAction(Intent.ACTION_PACKAGE_REPLACED);
filter.addDataScheme("package");
mContext.registerReceiver(new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
updateKeyboardLayouts();
}
}, filter, null, mHandler);
filter = new IntentFilter(BluetoothDevice.ACTION_ALIAS_CHANGED);
mContext.registerReceiver(new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
reloadDeviceAliases();
}
}, filter, null, mHandler);
mHandler.sendEmptyMessage(MSG_RELOAD_DEVICE_ALIASES);
mHandler.sendEmptyMessage(MSG_UPDATE_KEYBOARD_LAYOUTS);
if (mWiredAccessoryCallbacks != null) {
mWiredAccessoryCallbacks.systemReady();//調用systemReady()方法；繼續看下幹嘛的？
}
///M:[ALPS01762006]Delay the keyboard change notification until NotificationBar is ready @{
synchronized (mInputDevicesLock) {
if (!mPendingMessages.isEmpty()) {
Slog.d(TAG, "Input Manager has " + mPendingMessages.size() + " pending messages");
for (int i = ; i < mPendingMessages.size() ; i++) {
mPendingMessages.get(i).sendToTarget();
}
mPendingMessages.clear();
}
}
/// @}
}
WiredAccessoryManager.java中：
@Override
public void systemReady() {
synchronized (mLock) {
mWakeLock.acquire();
Log.d("qdd","systemReady --- sendmessage ---MSG_SYSTEM_READY");
Message msg = mHandler.obtainMessage(MSG_SYSTEM_READY, , , null);//發送消息，繼續跟
mHandler.sendMessage(msg);
}
}
private final Handler mHandler = new Handler(Looper.myLooper(), null, true) {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_NEW_DEVICE_STATE:
Log.d("qdd","wiredAccessoryManager --- mHandler -- MSG_NEW_DEVICE_STATE --->setDevicesState : arg1 = " + msg.arg1 + ";arg2 = " + msg.arg2 + ";obj = " + (String)msg.obj);
setDevicesState(msg.arg1, msg.arg2, (String)msg.obj);
mWakeLock.release();
break;
case MSG_SYSTEM_READY:
Log.d("qdd","wiredAccessoryManager --- mHandler -- MSG_SYSTEM_READY --->onSystemReady");
onSystemReady();//再繼續跟
mWakeLock.release();
break;
}
}
};
private void onSystemReady() {
if (mUseDevInputEventForAudioJack) {//config中配置這裡為false。
int switchValues = ;
if (mInputManager.getSwitchState(-, InputDevice.SOURCE_ANY, SW_HEADPHONE_INSERT) == ) {
switchValues |= SW_HEADPHONE_INSERT_BIT;
}
if (mInputManager.getSwitchState(-, InputDevice.SOURCE_ANY, SW_MICROPHONE_INSERT) == ) {
switchValues |= SW_MICROPHONE_INSERT_BIT;
}
if (mInputManager.getSwitchState(-, InputDevice.SOURCE_ANY, SW_LINEOUT_INSERT) == ) {
switchValues |= SW_LINEOUT_INSERT_BIT;
}
Log.d("qdd","wiredAccessoryManager --- onSystemReady --> notifyWiredAccessoryChanged switchValues = " + switchValues);
notifyWiredAccessoryChanged(, switchValues,SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT | SW_LINEOUT_INSERT_BIT);
}
Log.d("qdd","wiredAccessoryManager --- onSystemReady --> mObserver.init()");
mObserver.init();//很好，這裡看到mObserver了，跟下去。
}
void init() {
synchronized (mLock) {
if (LOG) Slog.v(TAG, "init()");
char[] buffer = new char[];
for (int i = ; i < mUEventInfo.size(); ++i) {
UEventInfo uei = mUEventInfo.get(i);
try {
int curState;
FileReader file = new FileReader(uei.getSwitchStatePath());
int len = file.read(buffer, , );
file.close();
curState = Integer.parseInt((new String(buffer, , len)).trim());
if (curState > ) {
Log.d("qdd","wiredAccessoryManager --- WiredAccessoryObserver -- init -->updateStateLocked");
updateStateLocked(uei.getDevPath(), uei.getDevName(), curState);
}
} catch (FileNotFoundException e) {
Slog.w(TAG, uei.getSwitchStatePath() +" not found while attempting to determine initial switch state");
} catch (Exception e) {
Slog.e(TAG, "" , e);
}
}
}
// At any given time accessories could be inserted
// one on the board, one on the dock and one on HDMI:
// observe three UEVENTs
for (int i = ; i < mUEventInfo.size(); ++i) {
UEventInfo uei = mUEventInfo.get(i);
startObserving("DEVPATH="+uei.getDevPath());//是的，有了，這裡就是開始監聽耳機的UEvent事件了。
}
}
開啟監聽的過程就這樣理清了，接下來看下監聽是怎麼處理的：
WiredAccessoryObserver中的回調方法：
@Override
public void onUEvent(UEventObserver.UEvent event) {
if (LOG) Slog.v(TAG, "Headset UEVENT: " + event.toString());
try {
String devPath = event.get("DEVPATH");
String name = event.get("SWITCH_NAME");
int state = Integer.parseInt(event.get("SWITCH_STATE"));//擷取切換的狀态
synchronized (mLock) {
Log.d("qdd","wiredAccessoryManager --- onUEvent -->updateStateLocked");
updateStateLocked(devPath, name, state);//更新狀态，跟進去看下怎麼處理的
}
} catch (NumberFormatException e) {
Slog.e(TAG, "Could not parse switch state from event " + event);
}
}
private void updateStateLocked(String devPath, String name, int state) {
for (int i = ; i < mUEventInfo.size(); ++i) {
UEventInfo uei = mUEventInfo.get(i);
Log.d("qdd","wiredAccessoryManager --- updateStateLocked : devPath = " + devPath + " ; uei.getDevPath() = " + uei.getDevPath() + " ; ---> updateLocked");
if (devPath.equals(uei.getDevPath())) {
updateLocked(name, uei.computeNewHeadsetState(mHeadsetState, state));//繼續跟
return;
}
}
}
/**
* Compare the existing headset state with the new state and pass along accordingly. Note
* that this only supports a single headset at a time. Inserting both a usb and jacked headset
* results in support for the last one plugged in. Similarly, unplugging either is seen as
* unplugging all.
*
* @param newName One of the NAME_xxx variables defined above.
* @param newState 0 or one of the BIT_xxx variables defined above.
*/
private void updateLocked(String newName, int newState) {
// Retain only relevant bits
int headsetState = newState & SUPPORTED_HEADSETS;
int usb_headset_anlg = headsetState & BIT_USB_HEADSET_ANLG;
int usb_headset_dgtl = headsetState & BIT_USB_HEADSET_DGTL;
int h2w_headset = headsetState & (BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT);
boolean h2wStateChange = true;
boolean usbStateChange = true;
if (LOG) Slog.v(TAG, "newName=" + newName
+ " newState=" + newState
+ " headsetState=" + headsetState
+ " prev headsetState=" + mHeadsetState);
if (mHeadsetState == headsetState) {
Log.e(TAG, "No state change.");
return;
}
// reject all suspect transitions: only accept state changes from:
// - a: 0 headset to 1 headset
// - b: 1 headset to 0 headset
if (h2w_headset == (BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT)) {
Log.e(TAG, "Invalid combination, unsetting h2w flag");
h2wStateChange = false;
}
// - c: 0 usb headset to 1 usb headset
// - d: 1 usb headset to 0 usb headset
if (usb_headset_anlg == BIT_USB_HEADSET_ANLG && usb_headset_dgtl == BIT_USB_HEADSET_DGTL) {
Log.e(TAG, "Invalid combination, unsetting usb flag");
usbStateChange = false;
}
if (!h2wStateChange && !usbStateChange) {
Log.e(TAG, "invalid transition, returning ...");
return;
}
mWakeLock.acquire();
Log.i(TAG, "MSG_NEW_DEVICE_STATE");
Log.i("qdd", "updateLocked --- sendmessage --- MSG_NEW_DEVICE_STATE");
Message msg = mHandler.obtainMessage(MSG_NEW_DEVICE_STATE, headsetState,mHeadsetState, "");//又是消息，繼續跟。
mHandler.sendMessage(msg);
mHeadsetState = headsetState;
}
private final Handler mHandler = new Handler(Looper.myLooper(), null, true) {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_NEW_DEVICE_STATE:
Log.d("qdd","wiredAccessoryManager --- mHandler -- MSG_NEW_DEVICE_STATE --->setDevicesState : arg1 = " + msg.arg1 + ";arg2 = " + msg.arg2 + ";obj = " + (String)msg.obj);
setDevicesState(msg.arg1, msg.arg2, (String)msg.obj);//繼續跟
mWakeLock.release();
break;
case MSG_SYSTEM_READY:
Log.d("qdd","wiredAccessoryManager --- mHandler -- MSG_SYSTEM_READY --->onSystemReady");
onSystemReady();
mWakeLock.release();
break;
}
}
};
private void setDevicesState(int headsetState, int prevHeadsetState, String headsetName) {
synchronized (mLock) {
int allHeadsets = SUPPORTED_HEADSETS;
for (int curHeadset = ; allHeadsets != ; curHeadset <<= ) {
if ((curHeadset & allHeadsets) != ) {
setDeviceStateLocked(curHeadset, headsetState, prevHeadsetState, headsetName);//繼續，繼續
allHeadsets &= ~curHeadset;
}
}
}
}
private void setDeviceStateLocked(int headset,int headsetState, int prevHeadsetState, String headsetName) {
if ((headsetState & headset) != (prevHeadsetState & headset)) {
int outDevice = ;
int inDevice = ;
int state;
if ((headsetState & headset) != ) {
state = ;
} else {
state = ;
}
if (headset == BIT_HEADSET) {//這裡就是根據耳機的類型，設定相應的音頻輸入和輸出裝置了
outDevice = AudioManager.DEVICE_OUT_WIRED_HEADSET;
inDevice = AudioManager.DEVICE_IN_WIRED_HEADSET;
} else if (headset == BIT_HEADSET_NO_MIC){
outDevice = AudioManager.DEVICE_OUT_WIRED_HEADPHONE;
} else if (headset == BIT_LINEOUT){
outDevice = AudioManager.DEVICE_OUT_LINE;
} else if (headset == BIT_USB_HEADSET_ANLG) {
outDevice = AudioManager.DEVICE_OUT_ANLG_DOCK_HEADSET;
} else if (headset == BIT_USB_HEADSET_DGTL) {
outDevice = AudioManager.DEVICE_OUT_DGTL_DOCK_HEADSET;
} else if (headset == BIT_HDMI_AUDIO) {
outDevice = AudioManager.DEVICE_OUT_HDMI;
} else {
Slog.e(TAG, "setDeviceState() invalid headset type: "+headset);
return;
}
if (LOG)
Slog.v(TAG, "device "+ headsetName+((state == ) ? " connected" : " disconnected"));
//ALPS00708321:add for AB=00->01, set device BIT_HEADSET will ingore and music will pause when plug in
// headset complete,so need delay to confirm set device BIT_HEADSET to Audio
if (prevHeadsetState == BIT_HEADSET_NO_MIC && headsetState == BIT_HEADSET && state == ) {
try {
Thread.sleep();
} catch (InterruptedException e) {
// Ingore
}
}
Log.d(TAG, "WiredHeadset num_hs_pole is " + num_hs_pole);
if (state == ){
if (num_hs_pole != "NA")
mAudioManager.setParameters(num_hs_pole);//這個參數是幹什麼的？跟到C++的代碼，看不懂了
}
if (outDevice != ) {
mAudioManager.setWiredDeviceConnectionState(outDevice, state, "", headsetName);//連接配接輸出裝置
}
if (inDevice != ) {
mAudioManager.setWiredDeviceConnectionState(inDevice, state, "", headsetName);//連接配接輸入裝置，繼續跟下，看看這個方法做什麼的。
}
illegal_state = getIllegalHeadset();
if ( == illegal_state) {
mHandler.postDelayed(new Runnable() {
public void run() {
illegal_state = getIllegalHeadset();
if ( == illegal_state) {
Slog.d(TAG, "show illegal Headset msg+++++++++++++");
showheadsetToast();
illegal_state = ;
} else {
Slog.d(TAG, "don't show illegal Headset msg+++++++++++++");
illegal_state = ;
}
}
}, );
//illegal_state = 0;
}
}
}
最後調用的是AudioService.java中的setWiredDeviceConnectionState方法：
public void setWiredDeviceConnectionState(int type, int state, String address, String name,String caller) {
synchronized (mConnectedDevices) {
if (DEBUG_DEVICES) {
Slog.i(TAG, "setWiredDeviceConnectionState(" + state + " nm: " + name + " addr:" + address + ")");
}
int delay = checkSendBecomingNoisyIntent(type, state);
queueMsgUnderWakeLock(mAudioHandler,
MSG_SET_WIRED_DEVICE_CONNECTION_STATE, //handler處理，跟這個消息
,
,
new WiredDeviceConnectionState(type, state, address, name, caller),
delay);
}
}
@Override
public void handleMessage(Message msg) {
// ...
case MSG_SET_WIRED_DEVICE_CONNECTION_STATE:
{ WiredDeviceConnectionState connectState = (WiredDeviceConnectionState)msg.obj;
onSetWiredDeviceConnectionState(connectState.mType, connectState.mState,
connectState.mAddress, connectState.mName, connectState.mCaller); //跟下去；
mAudioEventWakeLock.release();
}
break;
// ...
}
private void onSetWiredDeviceConnectionState(int device, int state, String address,String deviceName, String caller) {
if (DEBUG_DEVICES) {
Slog.i(TAG, "onSetWiredDeviceConnectionState(dev:" + Integer.toHexString(device)
+ " state:" + Integer.toHexString(state)
+ " address:" + address
+ " deviceName:" + deviceName
+ " caller: " + caller + ");");
}
synchronized (mConnectedDevices) {
Log.d(TAG, "onSetWiredDeviceConnectionState:" + "device:" + device + ",state:" + state);
/**
* M: do not broadcast if headset is connected for ALPS00850163 @{
*/
boolean shouldNotify = true;
if ((state == ) && ((device == AudioSystem.DEVICE_OUT_WIRED_HEADSET) ||
(device == AudioSystem.DEVICE_OUT_WIRED_HEADPHONE) ||
(device == AudioSystem.DEVICE_OUT_LINE))) {
/**
* M: do not setForceUse if headset is connected for
* ALPS00657344 @{
*/
boolean isHeadphoneOff = (device == AudioSystem.DEVICE_OUT_WIRED_HEADPHONE);
boolean isHeadsetOn = mConnectedDevices.containsKey(new StringBuilder().append("0x")
.append(AudioSystem.DEVICE_OUT_WIRED_HEADSET).append(":").toString());
if (isHeadphoneOff && isHeadsetOn) {
shouldNotify = false;
Log.d(TAG, "onSetWiredDeviceConnectionState() no need to setForceUse");
}
if (shouldNotify) {
// @}
setBluetoothA2dpOnInt(true);
/// M: ALPS00657344 @{
}
/** @} */
}
boolean isUsb = ((device & ~AudioSystem.DEVICE_OUT_ALL_USB) == ) ||
(((device & AudioSystem.DEVICE_BIT_IN) != ) &&
((device & ~AudioSystem.DEVICE_IN_ALL_USB) == ));
if (!handleDeviceConnection(state == , device, address, deviceName)) {
// change of connection state failed, bailout
return;
}
if (state != ) {
if ((device == AudioSystem.DEVICE_OUT_WIRED_HEADSET) ||
(device == AudioSystem.DEVICE_OUT_WIRED_HEADPHONE) ||
(device == AudioSystem.DEVICE_OUT_LINE)) {
setBluetoothA2dpOnInt(false);
}
if ((device & mSafeMediaVolumeDevices) != ) {
sendMsg(mAudioHandler,
MSG_CHECK_MUSIC_ACTIVE,
SENDMSG_REPLACE,
,
,
caller,
MUSIC_ACTIVE_POLL_PERIOD_MS);
}
// Television devices without CEC service apply software volume on HDMI output
if (isPlatformTelevision() && ((device & AudioSystem.DEVICE_OUT_HDMI) != )) {
mFixedVolumeDevices |= AudioSystem.DEVICE_OUT_HDMI;
checkAllFixedVolumeDevices();
if (mHdmiManager != null) {
synchronized (mHdmiManager) {
if (mHdmiPlaybackClient != null) {
mHdmiCecSink = false;
mHdmiPlaybackClient.queryDisplayStatus(mHdmiDisplayStatusCallback);
}
}
}
}
} else {
if (isPlatformTelevision() && ((device & AudioSystem.DEVICE_OUT_HDMI) != )) {
if (mHdmiManager != null) {
synchronized (mHdmiManager) {
mHdmiCecSink = false;
}
}
}
}
if (!isUsb && device != AudioSystem.DEVICE_IN_WIRED_HEADSET) {
//可以看到耳機插入，這裡發送廣播給上層app去接收。systemui會接收該廣播，顯示耳機插入圖示。當然可以繼續往下跟。直到sendbroadcast。
sendDeviceConnectionIntent(device, state, address, deviceName, shouldNotify);
}
}
}
問題來了，framework這邊是監聽UEvent事件。那麼kernel那邊是怎麼傳遞UEvent事件的？何時寫那個event節點？
在kernel下面的Accdet.c和Switch_class.c檔案中，但是看不懂。下面看下正常的log資訊。(一次插拔)
上層log：
main.log:
Line : - :: D AudioHeadSetMessager: /sys/class/switch/h2w/state =>
//這個是上層列印節點資訊，為表示沒插耳機。但是這個資訊并不是實時的，有觸發條件才列印這個資訊。
Line : - :: I WiredAccessoryManager: MSG_NEW_DEVICE_STATE
Line : - :: D WiredAccessoryManager: WiredHeadset num_hs_pole is num_hs_pole= //耳機插入後，設定音頻回路
Line : - :: D AudioHeadSetMessager: /sys/class/switch/h2w/state =>
Line : - :: I WiredAccessoryManager: MSG_NEW_DEVICE_STATE
Line : - :: D WiredAccessoryManager: WiredHeadset num_hs_pole is NA //耳機拔出。
sys.log:(UEVENT事件)
Line : - :: V WiredAccessoryManager: Headset UEVENT: {SUBSYSTEM=switch, SEQNUM=2534, ACTION=change, SWITCH_STATE=1, SWITCH_NAME=h2w, DEVPATH=/devices/virtual/switch/h2w}
Line : - :: V WiredAccessoryManager: Headset UEVENT: {SUBSYSTEM=switch, SEQNUM=2535, ACTION=change, SWITCH_STATE=0, SWITCH_NAME=h2w, DEVPATH=/devices/virtual/switch/h2w}
kernel.log:
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state= //目前耳機狀态
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state=
Line : - :: D [ ]-()[:display_idle_de][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state=
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]ACC EINT func :plug-in, cur_eint_state =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]ACC EINT func :plug-in, cur_eint_state =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet hardware init
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet hardware init
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet hardware init
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: enable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: enable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: enable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]enable_irq !!!!!!
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]enable_irq !!!!!! //耳機插入使能中斷，下面中斷處理
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [accdet_int_handler]....
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [accdet_int_handler]....
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:pmic_thread][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet interrupt happen:[Plug_out]current AB =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet interrupt happen:[Plug_out]current AB =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]accdet interrupt happen:[Plug_out]current AB =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]check_cable_type:Clear interrupt:Done[]!
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]check_cable_type:Clear interrupt:Done[]!
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]cable type:[Headset_mic], status switch:[Plug_out]->[Headset_plug_in]
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]cable type:[Headset_mic], status switch:[Plug_out]->[Headset_plug_in]
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [accdet] set state in cable_type status
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [accdet] set state in cable_type status //kernel 處理耳機插入完畢
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]Enter accdet_eint_func !!!!!!
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state= //耳機拔出了
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state=
Line : - :: D [ ]-()[:swapper/][name:accdet&]: [Accdet]accdet_eint_func after cur_eint_state=
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]ACC EINT func :plug-out, cur_eint_state =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]ACC EINT func :plug-out, cur_eint_state =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]clear_accdet_interrupt: ACCDET_IRQ_STS =
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: disable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: disable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: accdet: disable_accdet
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [accdet] set state in cable_type = NO_DEVICE //耳機拔出了
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [accdet] set state in cable_type = NO_DEVICE
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]enable_irq !!!!!!
Line : - :: D [ ] ()[:kworker/u8:][name:accdet&]: [Accdet]enable_irq !!!!!!
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