Since people have been reaching this blog from Google, I might as well say this once and for all instead of in individual emails. It seems as though the touchpad is supposed to be fully supported in Linux kernel 3.18. Debian Jessie, which I'm using, only runs 3.16 as of now.
I could compile 3.18 myself, but I don't feel like I have the time to get
into that right now.
#debian promises that kernel version 4.0 will
be backported Soon™, at which point the touchpad should start working perfectly
even in Debian Jessie.
If you are running anything more modern, like, I don't know, Arch Linux, it's probably already working for you.
Update! The 4.0 kernel has been backported to Jessie, and the touchpad indeed works as it is supposed to. Rejoice!