Cannot change ClickPad areas in synclient/xinput

[Justin Chiu]

I have run into trouble trying to configure the ClickPad areas of the
Cypress trackpad in the Dell XPS 13. By default, if I press the left
button, I get a left click, if I press the right button, I get a right
click. I would like to change these areas (perhaps disable the right
button and/or add a middle button).

Setting in synclient the RightButtonAreaLeft/etc. does not seem to
produce a change in the area that registers a right button click.
Similarly, setting it in 50-synaptics.conf or setting it in xinput
"Synaptic Soft Button Areas" does not seem to produce a change.

Would it be possible that changing these options doesn't do anything
because the Cypress driver does not support these changes? See https://bugs.launchpad.net/ubuntu/+source/linux/+bug/978807/comments/108

I am running a fresh install of Ubuntu 13.04 (also tried on Xubuntu
13.04). Kernel 3.8.0-19 (everything else works, including backlight
and Wifi). My understanding is that I don't need to add the Sputnik
PPA because everything has been pushed into 13.04...

I confirm that synclient and xinput are accepting other options, e.g.
TouchpadOff, TapButton, ClickFinger.

Setting ClickPad to 0 does not turn the ClickPad left/right button
functionality off, too! Still, I can left and right button click in
the same trackpad areas.

Perhaps this is relevant:
I have noticed is that xinput test seems to show x,y coordinates that
correspond not to the position of a touch but to the position of the
mouse cursor on the screen (left upper corner being 0,0 and bottom
right corner being 1600,900). But synclient -m 1 (needs SHMConfig
enabled, set in 50-synaptics.conf) produces coordinates that
correspond to the touch position (bottom right corner being 1100,620).

This seems odd because the default RightButtonAreaLeft in synclient
(equivalently, the first value of Synaptics Soft Button Areas in
xinput) is set to 800 (exactly half of 1600, the x coordinate shown by
xinput when the cursor is at the right edge of the screen). Shouldn't
this be half of the right edge touch position, 550? Similarly with the
y coordinate.

Any insight would be much appreciated.