有个关于蓝牙耳机的按键怎么映射到系统里面的问题，刚刚看了一下。

1）如果是HFP按键，

则是耳机是通过AT命令发送到手机侧的。

代码位于BluetoothHandsfree.java

Hang-up 命令：

 

// Hang-up command

parser.register("+CHUP", new AtCommandHandler() {
               @Override            public AtCommandResult handleActionCommand() {
                   sendURC("OK");                if (isVirtualCallInProgress()) {
                       terminateScoUsingVirtualVoiceCall();                } else {
                       if (mCM.hasActiveFgCall()) {
                           PhoneUtils.hangupActiveCall(mCM.getActiveFgCall());                    } else if (mCM.hasActiveRingingCall()) {
                           PhoneUtils.hangupRingingCall(mCM.getFirstActiveRingingCall());                    } else if (mCM.hasActiveBgCall()) {
                           PhoneUtils.hangupHoldingCall(mCM.getFirstActiveBgCall());                    }                }                return new AtCommandResult(AtCommandResult.UNSOLICITED);            }        });

 

volumn - up声音大小

 

// Speaker Gain        parser.register("+VGS", new AtCommandHandler() {
               @Override            public AtCommandResult handleSetCommand(Object[] args) {
                   // AT+VGS=
    
         in range [0,15]                if (args.length != 1 || !(args[0] instanceof Integer)) {
                       return new AtCommandResult(AtCommandResult.ERROR);                }                mScoGain = (Integer) args[0];                int flag =  mAudioManager.isBluetoothScoOn() ? AudioManager.FLAG_SHOW_UI:0;                mAudioManager.setStreamVolume(AudioManager.STREAM_BLUETOOTH_SCO, mScoGain, flag);                return new AtCommandResult(AtCommandResult.OK);            }        });
    

 

2）如果是AVRCP按键：

则在，external\bluetooth\bluez\audio\control.c

1./* operands in passthrough commands */2.#define VOL_UP_OP              0x413.#define VOL_DOWN_OP            0x424.#define MUTE_OP                0x435.#define PLAY_OP                0x446.#define STOP_OP                0x457.#define PAUSE_OP                0x468.#define RECORD_OP              0x479.#define REWIND_OP              0x4810.#define FAST_FORWARD_OP        0x4911.#define EJECT_OP                0x4a12.#define FORWARD_OP              0x4b13.#define BACKWARD_OP            0x4c

1.staticstruct{2.       constchar*name;3.        uint8_t avrcp;4.        uint16_t uinput;5.} key_map[]={6.       {
   "PLAY",                PLAY_OP,                KEY_PLAYCD },7.       {
   "STOP",                STOP_OP,                KEY_STOPCD },8.       {
   "PAUSE",               PAUSE_OP,               KEY_PAUSECD },9.       {
   "FORWARD",             FORWARD_OP,             KEY_NEXTSONG },10.       {
   "BACKWARD",            BACKWARD_OP,            KEY_PREVIOUSSONG },11.       {
   "REWIND",              REWIND_OP,              KEY_REWIND },12.       {
   "FAST  FORWARD",       FAST_FORWARD_OP,        KEY_FASTFORWARD },13.       { NULL}14.};

 

1. for(i=0;  key_map[i].name!=  NULL; i++){2.                uint8_t key_quirks;3. 4.               if((operands[0]&0x7F)!=  key_map[i].avrcp)5.                       continue;6. 7.                DBG("AVRCP: %s %s",  key_map[i].name,  status);8. 9.                key_quirks= control->key_quirks[key_map[i].avrcp];10. 11.               if(key_quirks&  QUIRK_NO_RELEASE){12.                       if(!pressed){13.                                DBG("AVRCP:  Ignoring release");14.                               break;15.                       }16. 17.                        DBG("AVRCP: treating  key press as press + release");18.                        send_key(control->uinput,  key_map[i].uinput,1);19.                        send_key(control->uinput,  key_map[i].uinput,0);20.                       break;21.               }22. 23.                send_key(control->uinput,  key_map[i].uinput,  pressed);24.               break;25.       }

 

1.staticvoid  send_key(int fd,  uint16_t key,int pressed)2.{3.       if(fd<0)4.               return;5. 6.        send_event(fd,  EV_KEY, key, pressed);7.        send_event(fd,  EV_SYN, SYN_REPORT,0);8.}