9091端口及8998端口

#打开9091端口
adb root
adb shell setprop sys.usb.config diag,serial_cdev,rmnet,adb

#打开8998端口
#adb root
#adb remount
#adb shell
#cd /system/bin/
#mv usbeng usbeng_back
#setprop persist.usb.eng 1
#setprop persist.sys.usb.config mtp

有的时候我们使用“setprop persist.usb.eng 1”不起作用，仍然无法打开QXDM端口，可以尝试用下面的方法。（包括在USER variant上开启QXDM)

Write "01" to MiscTA 2470 by using FG4, then you can get QXDM log even if USER variant.

  
  1) Shutdown the device, and connect to FG4.
  2) Click on the TA editor button on FG4.
  3) Select Misc TA from Partition drop down, and input 2470 to Unit text box.
  4) Write 01 on first byte. 
  5) Press the Write to phone button.