Support for the LED in Synaptics touchpads in Xorg

This is patched kernel module for touchpads with enable/disable LED button in left corner.

Originally patches comes from Takashi Iwai from SUSE for supporting the LED in Synaptics touchpads.

This video show how these touchpads looks like.

Upstream

Kernel sources are taken from repo.or.cz at linux-rolling-stable (or linux-6.x.y) head. Changes will be monitored and applied.

git archive --remote="git://repo.or.cz/linux.git" "linux-rolling-stable" drivers/input/mouse | tar -x

Dependencies

This module work with xf86-input-synaptics-led patched Xorg driver.

Build

Module can be build from sources and compressed by xz:

git clone https://github.com/vantu5z/synaptics-led.git
cd synaptics-led/synaptics-led/mouse
make -C "/usr/lib/modules/$(uname -r)/build" M="$PWD" psmouse.ko
xz psmouse.ko

Install

Module psmouse.ko.xz should be installed to directory:
/usr/lib/modules/<kernel_version>/extramodules/

AUR synaptics-led or synaptics-led-dkms packages can be used for Arch Linux users.
DKMS version advantage - you don't need to reinstall module manually after every kernel update.

Load

To load or reload module you can use modprobe:

sudo modprobe -r psmouse
sudo modprobe psmouse

or just reboot PC.

Wayland

Wayland use libinput and I don't know how to detect doubletap on touchpad LED. You still can toggle LED by brightnessctl but touchpad should be toggled manually.

Hyprland

This script can be used to toggle touchpad (find device name by hyprctl devices):

state=$(brightnessctl -d psmouse::synaptics g)

if [ "$state" == 0 ] || [ "$1" == "off" ] && [ "$1" != "on" ]
then
    hyprctl keyword "device[synps/2-synaptics-touchpad]:enabled" false
    brightnessctl -d psmouse::synaptics s 100%
else
    hyprctl keyword "device[synps/2-synaptics-touchpad]:enabled" true
    brightnessctl -d psmouse::synaptics s 0%
fi

And hyprland config:

bind = $mainMod, T, exec, ~/.local/bin/my_hyprland_touchpad
#bind = $mainMod, t, exec, ~/.local/bin/my_hyprland_touchpad off
#bind = $mainMod Shift, t, exec, ~/.local/bin/my_hyprland_touchpad on

Links

https://github.com/perusio/xorg-synaptics-led-support
https://github.com/mmonaco/PKGBUILDs/tree/master/synaptics-led