Ubuntu下android手机通过usb连接电脑，显示"???????????? no permissions"问题

问题现象：
$adb devices
List of devices attached
???????????? no permissions

解决方法：

1、设置usb权限
$lsusb
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 004: ID 093a:2510 Pixart Imaging, Inc. Hama Optical Mouse
Bus 002 Device 002: ID 413c:2003 Dell Computer Corp. Keyboard
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 022: ID 0fce:6146 Sony Ericsson Mobile Communications AB
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

列表中，Bus 001 Device 022: ID 0fce:6146 Sony Ericsson Mobile Communications AB. 这一行为手机的usb使用端口，记录一下，id为0fce

$sudo vim /etc/udev/rules.d/70-android.rules
加入以下内容：
SUBSYSTEM=="usb", ATTRS{idVendor}=="0fce", ATTRS{idProduct}=="6146",MODE="0666"

运行命令，重启udev：
$sudo chmod a+rx /etc/udev/rules.d/70-android.rules

$sudo service udev restart

2、拔掉usb重新连上再执行：

//重新启动adb server
$sudo ./adb kill-server

$./adb devices

$./adb root

设置完成了
$adb devices
List of devices attached
434235313151564C4D45 device