Configuring two touchpads with `synclient`

Question

I have two touchpads connected: the one built into my laptop and an Apple Magic Trackpad. I want to adjust some settings of the Magic Trackpad (MinSpeed, MaxSpeed, etc.) and the problem is that synclient adjusts settings of the built-in touchpad and doesn’t affect Magic Trackpad.

Sometimes it suddenly starts affecting the Magic Trackpad and not the laptop’s built-in one (I guess this happened when I connected Magic Trackpad after starting X, but I’m not sure).

Anyway, is there a way to reliably tell synclient which touchpad to configure?

Answer 1

Recent versions of xf86-input-synaptics are configured through XInput2 properties, and synclient just emulates the old interface on top of that. (I think it just picks the first compatible device it can find.) Therefore you can use xinput instead:

$ xinput list-props "ETPS/2 Elantech Touchpad"

$ xinput set-prop "ETPS/2 Elantech Touchpad" "Synaptics Tap Time" 180

In case of identical device names, specify the numeric device ID instead.

Note that Xorg will soon migrate from the evdev+synaptics drivers to xf86-input-libinput, which is configurable only through XInput2 (and has slightly fewer settings, by the way).

$ xinput set-prop 11 "libinput Accel Speed" 1.0