Enabling middleclick scrolling in Ubuntu for Lenovo clickpads

The short version is that if you want to enable middleclick scrolling for Lenovo clickpads in Ubuntu, do this in a terminal:

sudo add-apt-repository ppa:bjornt/evdev
sudo apt-get update
sudo apt-get dist-upgrade

The commands above should upgrade the xserver-xorg-input-evdev package, as well as remove the xserver-xorg-input-synaptics and xserver-xorg-input-all packages.

Next you need to create a file at /usr/share/X11/xorg.conf.d/90-clickpad.conf with the following contents:

Section "InputClass"
    Identifier "Clickpad"
    MatchIsTouchpad "on"
    MatchDevicePath "/dev/input/event*"
    Driver "evdev"
    # Synaptics options come here.
    Option "Clickpad" "true"
    option "EmulatedMidButtonTime" "0"
    Option "SoftButtonAreas" "65% 0 0 40% 42% 65% 0 40%"
    Option "AreaBottomEdge" "0%"

Section "InputClass"
    Identifier   "TrackPoint"
    MatchProduct "TrackPoint"
    MatchDriver  "evdev"
    Option       "EmulateWheel"       "1"
    Option       "EmulateWheelButton" "2"
    Option       "XAxisMapping"       "6 7"

The interesting options are SoftButtonAreas and AreaBottomEdge. SoftButtonAreas specifies where the buttons should be. If you want the buttons at the top, itt should generally be in the form "R 0 0 H L R 0 H", where R is where the border between the middle and right buttons, H is the height of the buttons, and L is the border between the middle and left buttons.

The AreaBottomEdge turns off the touchpad, expect for clicking. If you want to keep using the touchpad, you can instead specify AreaTopEdge, with the same value you use for H. That would enable the touchpad below the buttons.

Unfortunately, you can't specify where the left button should be, instead if occupies everything that isn't the middle or right button. This is a bit annoying, since at least I tend to touch the touchpad with my palm when reaching for the middle button, which will result in a left click being registered instead of a middle click.

I created this package because Ubuntu doesn't quite support the clickpads that come in the newer Lenovo laptops. Ubuntu does support clickpads, and with the SoftButtonAreas config settings it's possible to have three soft buttons on the clickpad where the real buttons used to be. However, what's not supported out of the box is middleclick scrolling, where you hold the middle button and scroll with the trackpoint.

The main problem is that the clickpad is driven by synaptics and the trackpoint by evdev, and they can't communicate to generate the scroll events. Bae Taegil patched the evdev driver to basically include the synaptics driver. I've taken that patch and generated a package for Ubuntu 14.04. I've only added a package for Trusty, but I could add packages for other releases if needed. I will most likely add one for Utopic, when it becomes more stable.