输入子系统由输入子驱动层(input driver)，系统核心层(input core)和事件处理层(Event Handler)三部分组成。一个输入事件，比如滑动触摸屏都是通过input driver -> input core -> event handler -> user space 到达用户空间传给应用程序。
X server默认使用 libinput 驱动(xf86-input-libinput) 处理输入设备，xf86-input-evdev 和相关驱动是后备方案。配置文件是 /usr/share/X11/xorg.conf.d/ 中的
10-evdev.conf
和
40-libinput.conf
Udev由 systemd 通过 xorg-server提供，会自动检测硬件，使用 evdev 或 libinput 处理设备的输入.
Input Devices
/dev/input
Input Drivers
xserver-xorg-input-all 驱动包
xserver-xorg-input-evdev 键盘，触摸屏
xserver-xorg-input-vmmouse 鼠标
xserver-xorg-input-wacom 数位板/触摸板
其他
xserver-xorg-input-libinput 键盘
xserver-xorg-input-synaptics 触摸板 (即将弃用)
xserver-xorg-input-joystick 遥杆
xserver-xorg-input-mtrack 触摸板 （推荐使用）
xserver-xorg-input-mutrack 触摸板 (年久失修)
xserver-xorg-input-void 空输入设备
xserver-xorg-input-xwiimote Wii设备
xserver-xorg-input-acecad 绘图板
Input Conf
/etc/X11/xorg.conf
/usr/share/X11/xorg.conf.d/
/usr/share/X11/xkb
Input Log
/var/log/Xorg.0.log
linux下的触摸手势方案挺多，早先的touchegg，后来的libinput-gestures, 以及最近gebaar-libinput。当然紧跟libinput上有的xf86-input-mtrack配置更简单。
debian系列用户直接安装对应的驱动包即可，当然也可以手动编译安装最新的版本，地址在文末
apt-get install xserver-xorg-input-mtrack
xinput list
查看自己的触控板标识以及支持情况，比如我的
renothing@desktop:~[master]$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ ETPS/2 Elantech Touchpad id=12 [slave pointer (2)]
⎜ ↳ Logitech USB Optical Mouse id=9 [slave pointer (2)]
xinput list 12
Reporting 7 classes:
Class originated from: 12. Type: XIButtonClass
Buttons supported: 7
Button labels: "Button Left" "Button Middle" "Button Right" "Button Wheel Up" "Button Wheel Down" "Button Horiz Wheel Left" "Button Horiz Wheel Right"
Button state:
Class originated from: 12. Type: XIValuatorClass
Detail for Valuator 0:
Label: Rel X
Range: -1.000000 - -1.000000
Resolution: 0 units/m
Mode: relative
Class originated from: 12. Type: XIValuatorClass
...
懒得做说明，直接贴配置文件
/etc/X11/xorg.conf.d/10-mtrack.conf
：
Section "InputClass"
Identifier "ETPS/2 Elantech Touchpad"
MatchIsTouchpad "true"
Driver "mtrack"
MatchDevicePath "/dev/input/event*"
Option "Sensitivity" "1.1"
Option "FingerHigh" "5"
Option "FingerLow" "5"
Option "IgnoreThumb" "true"
Option "ThumbRatio" "70"
Option "ThumbSize" "25"
Option "IgnorePalm" "true"
# This ignores tap-to-click, which causes more problems than benefit in my experience
Option "TapButton1" "0"
Option "TapButton2" "0"
Option "TapButton3" "0"
# If you want a middle-click, then "ClickFinger2" should be value "2"
Option "ClickFinger1" "1"
Option "ClickFinger2" "1"
Option "ClickFinger3" "3"
Option "ButtonMoveEmulate" "true"
Option "ButtonIntegrated" "true"
Option "ButtonEnable" "true"
# "ButtonZonesEnable" means that your trackpad gets divided into three equal sections, where clicking any third of the touchpad sends the click code in "ClickFingerX". Since I didn't
want middle-click, the left two thirds of my touchpad are left click, and the right third is right click:
Option "ButtonZonesEnable" "false"
Option "ClickTime" "25"
# Ensures that bottom 5% of touchpad doesn't register taps
Option "EdgeBottomSize" "5"
Option "SwipeLeftButton" "8"
Option "SwipeRightButton" "9"
Option "SwipeUpButton" "0"
Option "SwipeDownButton" "0"
Option "SwipeDistance" "700"
# ScrollCoast makes touchpad feel a bit more Mac-like, although it coasts in chunks and isn't relative to speed at which two finger scroll was happening
Option "ScrollCoastDuration" "600"
Option "ScrollCoastEnableSpeed" "0.05"
# This sets up Macbook-like natural scroll. If you want to scroll down by swiping your fingers down, reverse the "5" and the "4" here:
Option "ScrollUpButton" "5"
Option "ScrollDownButton" "4"
Option "ScrollLeftButton" "7"
Option "ScrollRightButton" "6"
# Without this option set to a high value, there are types of click+hold-and-move functionality (most easily reproed by click and then move up-right) that get ignored
Option "Hold1Move1StationaryMaxMove" "1000"
# Smaller ScrollDistance translates to faster scrolling. ScrollDistance of 10 scrolls a long page in one swipe.
Option "ScrollDistance" "22"
Option "ScrollClickTime" "12"
Option "ScrollSensitivity" "0"
EndSection
具体配置选项请参考官网手册：https://github.com/p2rkw/xf86-input-mtrack
参考：