I'm on an E7240 running 12.04 LTS (anxiously awaiting my employeer to certify 14.04 with all our internal tools and what-not) and I have this problem. I'm pretty sure it happens because my middle and ring fingers accidentally touch the top edge of the pad while my pointer finger is moving the cursor. I can reproduce this on purpose by running "xinput --test [device number]" and watching the events while I do the following:
- Touch the pad near the middle or bottom. The cursor moves slightly as my finger wiggles around. - Without removing the first finger, touch the pad again with a second finger above the first finger. The cursor shoots up to a[1]=0 (which is the y position). - Without removing the first finger, remove the second (top) finger. The cursor shoots back down to a[1]=<some large number> Sometimes it takes it all the way to the bottom of the screen, sometimes it goes back to where it was, or somewhere else. I haven't been able to figure out how it decides what to go back to. With this, while I touching with my pointer finger and my middle or ring finger accidentally touch the pad at the top, the cursor shoots where I don't want it. Then when my middle/ring finger leaves the pad (usually because I started cursing (get it?) at my cursor), it shoots back down again somewhere completely arbitrary. Similarly: - Touch the bad near the top. - Without removing the top finger, touch somewhere near the bottom. The cursor doesn't (yet) move. - Lift the top finger. The cursor shoots to the bottom. - Put down the top finger again, without lifting the bottom. The cursor shoots back up again. You can make the cursor shoot up and down just by keeping your bottom finger down and tapping the top finger. The cursor follows the top finger no matter what you do. Interestingly, this does NOT happen from side-to-side. Two touches side-by-side trigger the multi-touch gestures and don't move the cursor. If we could just get it so that going from single touch to multi-touch top-to-bottom doesn't actually move the cursor, that would be grand. Thank you very much for all your help. :-) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1272624 Title: [Dell Latitude E7440] 14.04 Touchpad causing mouse pointer to spuriously jump around screen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1272624/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
