Enable two-finger scrolling on ALPS touchpad

First of all, to identify which touchpad you have, run

xinput list 

If it shows something like

...
↳ AlpsPS/2 ALPS GlidePoint                  id=14   [slave  pointer  (2)]
...

then you most probably do not have multitouch support. The Alps touchpads tend not to have multitouch, while they use the same driver as the Synaptic touchpads.

You can use synclient -l to obtain information on your touchpad.

Still, the definitive way to see how many fingers are supported on your touchpad, is to

1. Enable SHMConfig in your xorg.conf file
2. Run synclient -m 100, which will show in real time the status of your touchpad. The fifth column labeled f is for fingers, therefore you can see up to how many fingers you can tap at the same time.

To enable SHMConfig in xorg.conf, see http://mjg59.livejournal.com/118588.html and then add

Section "InputClass"
   Identifier "enable synaptics SHMConfig"
   MatchIsTouchpad "on"
   MatchDevicePath "/dev/input/event*"
   Option "SHMConfig" "on"
EndSection

to your xorg.conf. You can remove the above snippet once you performed your testing.

I was able to activate the two finger scrolling using the hack described by this post:

http://ubuntuforums.org/showpost.php?p=9058534&postcount=2

Unfortunately, the options get reset by some other daemon every once in a while and when the computer goes to sleep.

Hopefully someone can figure out another way to do this.

On the Sony VAIO VPCF136FM, the following command works to add edge scrolling on the ALPS touchpad in Ubuntu 12.04 (and Linux Mint 11, as an aside, if anyone cares):

Run from the terminal:

echo "options psmouse proto=imps"|sudo tee -a /etc/modprobe.d/psmouse.conf; sudo modprobe -r psmouse; sudo modprobe psmouse

Or, for readability, follow these steps instead, which do the same thing:

Create a file called "psmouse.conf" in /etc/modprobe.d:

sudo vim /etc/modprobe.d/psmouse.conf

Add the following line to this file, and save:

options psmouse proto=imps

Lastly, reload the drivers:

sudo modprobe -r psmouse
sudo modprobe psmouse

While this isn't two-finger scrolling, it's the next best thing, and the only type of touchpad scrolling that I've been able to get working on this platform. I'm pretty happy with it, and I hope it helps others.

The source was from Oscar's link: Source: [regression] Alps touchpad detected, but scrolling not working LP bug #737051, but I didn't need to install the driver or do anything else mentioned in that thread. I even undid some of the other things I tried, just to be sure the psmouse.conf file in /etc/modprobe.d is all I needed.

Also, note that this is a bit of a hack, as the touchpad is loaded as a ImPS/2 Generic Wheel Mouse, and the Touchpad tab disappears from the Mouse Settings menu. However, this is a lot less annoying than having to drag the mouse pointer to the sidebar everytime I want to scroll.

Lastly, I haven't yet rebooted on Linux Mint 11 (not that it matters much here), so the modprobe commands may need to be added to a startup script, if the edge scroll doesn't survive the reboot. However, on Ubuntu 12.04, the one that matters on AskUbuntu, the scroll continues to work even after the reboot.

I just found the dirver from an ubuntu DELL image shipped with my Latitude, check this answer: https://askubuntu.com/a/278133/65801