Trackballs over mice for me (except for gaming), thumb trackballs specifically, I like those best. The one thing I need is scroll-via-ball. Had this working on Windows via AutoHotkey with a smooth scrolling script, but that doesn’t carry over to Linux. Luckily KDE DE (Desktop Environment) has a core implementation for this. Here’s how I set it up.

How to do it?

Hardware identification

Identify your device, in my case is the logitech 575

# Check Logitech ERGO M575
cat /proc/bus/input/devices | grep -A 10 -B 2 -i "M575"

Output:

Vendor=046d Product=4096  # unique VID:PID
Name="Logitech ERGO M575"
Handlers=event9 mouse1

qdbus6 (Plasma Wayland)

# Find qdbus6
find /usr -name qdbus* 2>/dev/null
# → /usr/lib/qt6/bin/qdbus6 (Plasma 6)

Enable scroll with a custom button, went with the right button, tried middle click first and hated it, right felt more intuitive.

# Your M575 (event26 in my case)
# BTN_RIGHT

qdbus-qt6 org.kde.KWin /org/kde/KWin/InputDevice/event26 org.kde.KWin.InputDevice.scrollButton 273

Make it persistent at the user level:

kwriteconfig6 --file kcminputrc --group "Mouse" --key "ScrollButton" 273

Extra notes

#TODO in my fork of AutoHotkey, added an update so another click (besides right button) raises/lowers volume, haven’t gotten to porting that to Linux yet.