====== Disable notebook touchpad in GNU/Linx ======

Following this recipe you can disable or enable the touchpad of your **GNU/Linux notebook** using the **command line**. I used it to control the touchpad of my **Teclast F6**, where the Fn key to disable the touchpad does not work.

Install the **xinput** Debian package and run the following to list the X input devices:

<code>
xinput list
⎡ Virtual core pointer                          id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Logitech USB Receiver Consumer Control    id=8    [slave  pointer  (2)]
⎜   ↳ Logitech USB Receiver                     id=15   [slave  pointer  (2)]
⎜   ↳ SYNA3602:00 0911:5288 Touchpad            id=11   [slave  pointer  (2)]
⎣ Virtual core keyboard                         id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Video Bus                                 id=6    [slave  keyboard (3)]
    ↳ Power Button                              id=7    [slave  keyboard (3)]
    ↳ SHUNCCM2MP: SHUNCCM2MP                    id=10   [slave  keyboard (3)]
    ↳ Intel HID events                          id=12   [slave  keyboard (3)]
    ↳ Intel HID 5 button array                  id=13   [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=14   [slave  keyboard (3)]
    ↳ Logitech USB Receiver Consumer Control    id=9    [slave  keyboard (3)]
</code>

The ask more info about input the touchpad (ID #11 in the above example):

<code>
niccolo@ithaca:~$ xinput list-props 11    
Device 'SYNA3602:00 0911:5288 Touchpad':
        Device Enabled (154):   1
        Coordinate Transformation Matrix (156): 1.000000, ...
        Device Accel Profile (286):     1
        ...
</code>

The **Device Enabled** property has ID #154, we can disable it:

<code>
xinput set-prop 11 154 0
</code>

Replace the **zero** with **1** to re-enable it.

===== Mapping Fn+ESC on the Teclast F6 =====

The ESC key on the **Teclast F6 notebook** has the blue label indicating that the shortcut **Fn+ESC** should trigger the **touchpad toggle** function, but it does not work in GNU/Linux.

Using the **evtest** tool we can see that the Fn+ESC keys produces three events, i.e. it is the same as pressing three keys together:

<code>
Event: time 1620808296.082667, -------------- SYN_REPORT ------------
Event: time 1620808298.469045, type 4 (EV_MSC), code 4 (MSC_SCAN), value 1d
Event: time 1620808298.469045, type 1 (EV_KEY), code 29 (KEY_LEFTCTRL), value 1
Event: time 1620808298.469045, -------------- SYN_REPORT ------------
Event: time 1620808298.471997, type 4 (EV_MSC), code 4 (MSC_SCAN), value db
Event: time 1620808298.471997, type 1 (EV_KEY), code 125 (KEY_LEFTMETA), value 1
Event: time 1620808298.471997, -------------- SYN_REPORT ------------
Event: time 1620808298.473572, type 4 (EV_MSC), code 4 (MSC_SCAN), value 76
Event: time 1620808298.473572, type 1 (EV_KEY), code 85 (KEY_ZENKAKUHANKAKU), value 1
</code>

The keys are **Left Control**, **Left Meta** (also known as //Left Windows Logo// key) and the key used to toggle from Zenkaku (full-width) to Hankaku (half-width) Japanese character spacing :-O

Using **udev** I remapped the ''ZENKAKUHANKAKU'' key to the more useable **ESC** (see this page about **[[remap_keyboard_keys#customize_events_using_udev|customize udev events]]**):

<file>
evdev:atkbd:dmi:*
 KEYBOARD_KEY_76=esc
</file>

If you are interested, I have a more complete configuration file which I use also to swap the **Fn key** behaviour on function keys (I want them to work as first option, instead of multimedia buttons). See this page about **[[remap_keyboard_keys#configuration_example_for_the_teclast_f6_notebook|rempapping keyboard keys]]**.

Finally, using the XFCE **Settings** => **Keyboard**, I associated the **Ctrl+Super+Escape** keyboard shortcut (where //Super// means //Left Windows Logo//) to the following shell script **/usr/local/bin/touchpad-toggle**:

<code bash>
#!/bin/sh
STATE="$(xinput --list-props 11 | egrep '^\s+Device Enabled' | rev | awk '{print $1}')"
set_on() {
    xinput set-prop 11 154 1
    echo "Touchpad enabled"
}
set_off() {
    xinput set-prop 11 154 0
    echo "Touchpad disabled (pass \"1\" as first option to re-enable it)"
}
case "$1" in
    on|yes|1)
        set_on
        ;;
    off|no|0)
        set_off
        ;;
    *)
        if [ "$STATE" -eq "1" ]; then
            set_off
        else
            set_on
        fi
        ;;
esac
</code>

**NOTICE**: I usually use the **Left Windows Logo** key as the **compose key**, to type international characters. Unfortunately the compose key cannot be used into an XFCE keyboard shortcut, so I changed my compose key to the **Menu key** (the one at the right of the space).
===== Web References =====

  * **[[https://www.nico.schottelius.org/blog/xorg-disable-touchpad-with-xinput/| How to disable the touchpad in Xorg with xinput]]**