Thinkpad X220 touchpad issues

Question

I've had some issues with my touchpad that have appeared in the last day or so. The touchpad in question is one of those "buttonless" designs that instead has a single physical button under the touchpad, so that you press down on the touchpad to physically click (this is independent of tap-to-click, which I usually have turned off). The touchpad previously treated two finger clicks as right clicks, and three finger clicks as middle clicks, and has since stopped doing this. Sometimes, when I click down on the touchpad, it won't let me move the mouse cursor... this is rather intermittent, and happens some times and not others.
I've tested this under a Linut Mint live USB environment, and it works as expected there, suggesting that it isn't a hardware issue. If I enable tap-to-click, it behaves in the expected way for tapping, but not the physical clicking of the touchpad button. As far as I can remember, the desired behavior specified above was the default behavior, at least under the Gnome 3 desktop that I use. I've had a look around the wiki for info, and any of the things I've tried, such as the "MatchDevicePath" stuff, doesn't work.
Any ideas?

Answer 1

Current version of xf86-input-synaptics in Arch has the new multi touch support for clickpads (what you call butonless design on new ProBook's and ThinkPad's) using mtdev library. It differs from previous hacks which enabled support, hacks that found their way into SuSE, Ubuntu etc. releases, and this one works different.
There are two new properties you can use in your synaptics configuration now:
    Option     "ClickPad"         "true"
    Option     "SoftButtonAreas"  "3507 0 3918 0 0 0 0 0"
First enables clickpad support, and second defines what are the right button and middle button areas. The values you see in SoftButtonAreas are the ones I have been playing with so far on my own laptop. For more information read SoftButtonAreas section in man 4 synaptics.
To help you find the right values for your self here are some tricks I've been using as well. The above SoftButtonAreas values on my clickpad result in these properties being set:
$ synclient | grep -i button
    RightButtonAreaLeft     = 3507
    RightButtonAreaRight    = 0
    RightButtonAreaTop      = 3918
    RightButtonAreaBottom   = 0
    MiddleButtonAreaLeft    = 0
    MiddleButtonAreaRight   = 0
    MiddleButtonAreaTop     = 0
    MiddleButtonAreaBottom  = 0
From here you can tweak the values on the fly, until you find suitable boundaries to use for right and middle click, and then backport them into synaptics configuration:
$ synclient RightButtonAreaLeft=3300 RightButtonAreaTop=3999
Last edited by anrxc (2012-03-26 01:33:18)