I've recently upgraded from utopic to vivid (14.10 to 15.04) and whilst there are a few small issues the main thing is that my touchpad (logitech t650) is not working as it was, specifically I can no longer use a 3 fingered swipe left or right to move backwards or forwards in a browser, or nautilus when looking through files, other than that the touchpad works fine, although it does need tweaking as it isn't as smooth to use as it was in utopic.
I have tried numerous things and had no luck, I've already upgraded the firmware by the way, the annoying thing is I can plug it into my wifes system (running 14.04) and it works perfectly with no configuration (including 3 fingered gestures), this was also the case in utopic but not for vivid, as far as I can tell it no longer supports 3 fingered gestures in vivid, I've tried programs like easytouch, touchegg and some others but all of them don't see the 3 fingered gestures, I also used geisview to see what the touchpad is capable of, and according to that it's not capable of 3 fingered gestures.
In all honesty I'm at a bit of a loss as to what it might be, so any ideas would be appreciated.
Edit :
Since writing this I have been doing some experimenting, and I have found at least for me a way to get 3 fingered swiping, I basically use it for browser navigation, but with more tweaking it might be possible to get a lot more of the touchpads functions working.
After searching I came across this – multitouch gestures it's taken a bit of messing about with, but that's more my lack of knowledge than anything else, I did have some issues when running some of the commands (specifically the make commands) turns out this might be down to glibc, but I found that using this source solved the make issues clone from here if having make issues
I still have some issues with the touchpad, but this seems to be a step in the right direction, hope it helps.
Best Answer
In kernel 3.19 (as included with Ubuntu 15.04 Vivid) the Logitech HID++ driver got rewritten to improve support for certain Logitech devices. This shifted processing of events from the hardware (the touchpad) to software (the Linux input driver stack).
This results in the Logitech T650 touchpad not sending keyboard events such as Back for three fingers. Since there is no multi-touch driver that processes gestures, you do not get the event either.
Workarounds:
A forward solution should recognize the multi-touch functionality of the Logitech T650 touchpad and then generate appropriate events for gestures.