I.MX6 GPS Android HAL Framework 调试

                         I.MX6 GPS Android HAL Framework 调试

一、参考文章：
    android4.3 GPS定位问题
        http://blog.csdn.net/bzw073/article/details/44341943

二、修改GPS配置文件：
    1. myzr@myzr:~/myandroid/device$ grep ttymxc2 * -R
        ......
        fsl/imx6/etc/ueventd.freescale.rc:/dev/ttymxc2              0660   system     gps
        fsl/sabresd_6dq/init.rc:    symlink /dev/ttymxc2 /dev/gpsdevice
        fsl/imx5x/ueventd.freescale.rc:/dev/ttymxc2              0600   bluetooth  bluetooth
        fsl/imx53_smd/init.freescale.rc:#service hciattach /system/bin/logwrapper /system/bin/hciattach -n -s 115200 /dev/ttymxc2 ath3k 3000000 flow sleep
        fsl-proprietary/gps/Orion.ini:;ReceiverComPortName=/dev/ttymxc2
        ......
    
    2. cat fsl/imx6/etc/ueventd.freescale.rc
        ......
        /dev/ttymxc1              0660   system     gps   <----- zengjf modified
        /dev/ttya0                0660   system     gps
        /dev/ptya0                0660   system     gps
        /dev/ttya1                0660   system     gps
        /dev/ptya1                0660   system     gps
        ......
        
    3. cat fsl/sabresd_6dq/init.rc
        ......
        # Set GPS serial and reset GPIO pin
        setprop ro.kernel.android.gps /dev/ttymxc1        <----- zengjf modified
        setprop persist.gps.oacmode @f
        symlink /dev/ttymxc1 /dev/gpsdevice               <----- zengjf modified
        write /sys/class/gpio/export 60
        write /sys/class/gpio/gpio60/direction "out"
        write /sys/class/gpio/gpio60/value 1
        ......
    
    4. cat fsl-proprietary/gps/Orion.ini
        ......
        ; GPS Receiver COM Port Baud Rate for boot, 115200, 230400, 460800, 921600,     or custom
        ReceiverComPortBootSpeed=9600　　　　　　　　　　　　<----- zengjf modified
        ReceiverComPortName=/dev/ttymxc1                 <----- zengjf modified
        ......

三、修改Atheros GPS HAL代码：
    1. 代码位置：/home/myzr/myandroid/hardware/imx/libgps/athr_gps.c
    2. GPS调试，当然要打开调试功能了：
        ......
        #define  GPS_DEBUG
        /* #undef    GPS_DEBUG_TOKEN */ /* print out NMEA tokens */
        #define  GPS_DEBUG_TOKEN    /* print out NMEA tokens */
        ......
    3. 修改tty 串口默认通信波特率：
        int gps_opentty(GpsState *state)
        {
            ......
            // disable echo on serial lines
            if ( isatty( state->fd ) ) {
                struct termios  ios;
                tcgetattr( state->fd, &ios );
                bzero(&ios, sizeof(ios));
                //ios.c_cflag = B115200 | CS8 | CLOCAL | CREAD;
                ios.c_cflag = B9600 | CS8 | CLOCAL | CREAD;   <----- zengjf modified
                ios.c_iflag = IGNPAR;
                ios.c_oflag = 0;
                ios.c_lflag = 0;  /* disable ECHO, ICANON, etc... */
                tcsetattr( state->fd, TCSANOW, &ios );
                tcflush(state->fd,TCIOFLUSH);
            } 
            ......
        }

四、修改GPS LocationManagerService代码：
    1. 代码位置：/home/myzr/myandroid/frameworks/base/services/java/com/android/server/LocationManagerService.java
    2. 具体原因请参考《参考文章》
        @Override
        public void reportLocation(Location location, boolean passive) {
            checkCallerIsProvider();
        
            // 2015-11-2 zengjf modify for GPS module
            /*
            if (!location.isComplete()) {
                Log.w(TAG, "Dropping incomplete location: " + location);
                return;
            }
            */
            ......
        }

五、打开开发板GPS编译：
    1. 代码位置：/home/myzr/myandroid/device/fsl/sabresd_6dq/BoardConfig.mk
    2. 参考代码如下，没有任何修改：
        BOARD_HAVE_HARDWARE_GPS := true
        USE_ATHR_GPS_HARDWARE := true
        USE_QEMU_GPS_HARDWARE := false