Android 耳机插入过程分析
参考链接：
https://www.jianshu.com/p/d82a8dabb3e7
初始化：
10-26 07:40:43.932 1414 1414 I SystemServer: StartWiredAccessoryManager
10-26 07:40:43.936 1414 1414 W WiredAccessoryManager: This kernel does not have usb audio support
10-26 07:40:43.937 1414 1414 W WiredAccessoryManager: This kernel does not have HDMI audio support
10-26 07:40:43.937 1414 1414 W WiredAccessoryManager: This kernel does not have DP audio support
10-26 07:40:43.937 1414 1414 D SystemServerTiming: StartWiredAccessoryManager took to complete: 6ms
10-26 07:40:46.375 1414 1414 V WiredAccessoryManager: notifyWiredAccessoryChanged: when=0 bits= mask=54
10-26 07:40:46.375 1414 1414 V WiredAccessoryManager: newName=h2w newState=0 headsetState=0 prev headsetState=0
10-26 07:40:46.375 1414 1414 E WiredAccessoryManager: No state change.
10-26 07:40:46.375 1414 1414 V WiredAccessoryManager: init()
耳机插入
10-26 11:26:48.552 1414 1684 V WiredAccessoryManager: notifyWiredAccessoryChanged: when=13604972191000 bits=SW_HEADPHONE_INSERT SW_MICROPHONE_INSERT mask=94
10-26 11:26:48.552 1414 1684 V WiredAccessoryManager: newName=h2w newState=1 headsetState=1 prev headsetState=0
10-26 11:26:48.554 1414 1684 I WiredAccessoryManager: MSG_NEW_DEVICE_STATE
10-26 11:26:48.555 1414 1414 V WiredAccessoryManager: headsetName: connected
耳机拔出
10-26 11:26:53.134 1414 1684 V WiredAccessoryManager: notifyWiredAccessoryChanged: when=13609554723000 bits= mask=94
10-26 11:26:53.134 1414 1684 V WiredAccessoryManager: newName=h2w newState=0 headsetState=0 prev headsetState=1
10-26 11:26:53.136 1414 1684 I WiredAccessoryManager: MSG_NEW_DEVICE_STATE
10-26 11:26:53.137 1414 1414 V WiredAccessoryManager: headsetName: disconnected
高通读取外设插入方式有两种：
1. UEvent：
读取/sys/class/switch/h2w/state文件等状态
2. InputEvent：
读取/dev/input/event
通过属性值,判断采用何种方式。
frameworks\base\core\res\res\values\config.xml
<bool name="config_useDevInputEventForAudioJack">true</bool>
getevent
add device 1: /dev/input/event7
name: "msm8953-snd-card-mtp Button Jack"
add device 2: /dev/input/event6
name: "msm8953-snd-card-mtp Headset Jack"
add device 3: /dev/input/event2
name: "goodix-ts"
add device 4: /dev/input/event3
name: "hbtp_vm"
could not get driver version for /dev/input/mouse0, Not a typewriter
add device 5: /dev/input/event0
name: "qpnp_pon"
could not get driver version for /dev/input/mice, Not a typewriter
add device 6: /dev/input/event1
name: "tsu6721"
add device 7: /dev/input/event4
name: "keyremap_virtual"
add device 8: /dev/input/event5
name: "gpio-keys"
插入：
/dev/input/event6: 0005 0002 00000001
/dev/input/event6: 0005 0004 00000001
/dev/input/event6: 0005 0007 00000001
/dev/input/event6: 0000 0000 00000000
拔出：
/dev/input/event6: 0005 0002 00000000
/dev/input/event6: 0005 0004 00000000
/dev/input/event6: 0005 0007 00000000
/dev/input/event6: 0000 0000 00000000
getevent -l
/dev/input/event6: EV_SW SW_HEADPHONE_INSERT 00000001
/dev/input/event6: EV_SW SW_MICROPHONE_INSERT 00000001
/dev/input/event6: EV_SW SW_JACK_PHYSICAL_INS 00000001
/dev/input/event6: EV_SYN SYN_REPORT 00000000
/dev/input/event6: EV_SW SW_HEADPHONE_INSERT 00000000
/dev/input/event6: EV_SW SW_MICROPHONE_INSERT 00000000
/dev/input/event6: EV_SW SW_JACK_PHYSICAL_INS 00000000
/dev/input/event6: EV_SYN SYN_REPORT 00000000
代码跟踪
frameworks\base\services\core\java\com\android\server\input\InputManagerService.java
mUseDevInputEventForAudioJack =
context.getResources().getBoolean(R.bool.config_useDevInputEventForAudioJack);
if (mUseDevInputEventForAudioJack && (switchMask & SW_JACK_BITS) != 0) {
mWiredAccessoryCallbacks.notifyWiredAccessoryChanged(whenNanos, switchValues,
switchMask);
}
frameworks\base\services\core\java\com\android\server\WiredAccessoryManager.java
public void notifyWiredAccessoryChanged(long whenNanos, int switchValues, int switchMask) {
if (LOG) Slog.v(TAG, "notifyWiredAccessoryChanged: when=" + whenNanos
+ " bits=" + switchCodeToString(switchValues, switchMask)
+ " mask=" + Integer.toHexString(switchMask));
synchronized (mLock) {
int headset;
mSwitchValues = (mSwitchValues & ~switchMask) | switchValues;
switch (mSwitchValues &
(SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT | SW_LINEOUT_INSERT_BIT)) {
case 0:
headset = 0;
break;
case SW_HEADPHONE_INSERT_BIT:
headset = BIT_HEADSET_NO_MIC;
break;
case SW_LINEOUT_INSERT_BIT:
headset = BIT_LINEOUT;
break;
case SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT:
headset = BIT_HEADSET;
break;
case SW_MICROPHONE_INSERT_BIT:
headset = BIT_HEADSET;
break;
default:
headset = 0;
break;
}
updateLocked(NAME_H2W,
(mHeadsetState & ~(BIT_HEADSET | BIT_HEADSET_NO_MIC | BIT_LINEOUT)) | headset);
}
}
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();
// 发送数据给
Log.i(TAG, "MSG_NEW_DEVICE_STATE");
Message msg = mHandler.obtainMessage(MSG_NEW_DEVICE_STATE, headsetState,
mHeadsetState, "");
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:
setDevicesState(msg.arg1, msg.arg2, (String)msg.obj);
mWakeLock.release();
break;
case MSG_SYSTEM_READY:
onSystemReady();
mWakeLock.release();
break;
}
}
};
private void setDevicesState(
int headsetState, int prevHeadsetState, String headsetName) {
synchronized (mLock) {
int allHeadsets = SUPPORTED_HEADSETS;
for (int curHeadset = 1; allHeadsets != 0; curHeadset <<= 1) {
if ((curHeadset & allHeadsets) != 0) {
setDeviceStateLocked(curHeadset, headsetState, prevHeadsetState, headsetName);
allHeadsets &= ~curHeadset;
}
}
}
}
private void setDeviceStateLocked(int headset,
int headsetState, int prevHeadsetState, String headsetName) {
if ((headsetState & headset) != (prevHeadsetState & headset)) {
int outDevice = 0;
int inDevice = 0;
int state;
if ((headsetState & headset) != 0) {
state = 1;
} else {
state = 0;
}
if (headset == BIT_HEADSET) {
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, "headsetName: " + headsetName +
(state == 1 ? " connected" : " disconnected"));
}
// 发送给audio manager.
if (outDevice != 0) {
mAudioManager.setWiredDeviceConnectionState(outDevice, state, "", headsetName);
}
if (inDevice != 0) {
mAudioManager.setWiredDeviceConnectionState(inDevice, state, "", headsetName);
}
}
}