确认安装了libinput的输入驱动，这样应该就好了吧。

没有触摸板 是点指+左右键

在libinput驱动出来前是需要专门的配置来用指点杆和中键模拟滚动的，下面是配置文件：

Wheel Emulation

New file /etc/X11/xorg.conf.d/10-wheel-emulation.conf

   # Accelerometer device, posts data through ABS_X/ABS_Y, making X unusable
   # http://bugs.freedesktop.org/show_bug.cgi?id=22442
   Section "InputClass"
       Identifier "Trackpoint Wheel Emulation"
       MatchProduct "TPPS/2 IBM TrackPoint|DualPoint Stick|Synaptics Inc. Composite TouchPad / TrackPoint|ThinkPad USB Keyboard with TrackPoint|USB Trackpoint pointing device"
       MatchDevicePath   "/dev/input/event*"
       Option      "EmulateWheel"      "true
       Option      "EmulateWheelButton"   "2"
       Option      "Emulate3Buttons"   "false"
       Option      "XAxisMapping"      "6 7"
       Option      "YAxisMapping"      "4 5"
   EndSection

但是libinput驱动出来后，就不需要了，除非你的笔记本太新，内核缺乏支持，那么没办法了。

libinput (简体中文)

sudo apt-get install libinput-tools

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