Ricardo's fix got the touchpad working for me (Lenovo ThinkPad R500), but edge-scrolling was disabled. So instead I just reloaded the psmouse module (i.e. without the proto argument), after which the touchpad worked perfectly:
sudo modprobe -r psmouse
sudo modprobe psmouse
To make this fix permanent I added the following to /etc/rc.local:
/sbin/modprobe -r psmouse
/sbin/modprobe psmouse
Ricardo's fix got the touchpad working for me (Lenovo ThinkPad R500), but edge-scrolling was disabled. So instead I just reloaded the psmouse module (i.e. without the proto argument), after which the touchpad worked perfectly:
sudo modprobe -r psmouse
sudo modprobe psmouse
To make this fix permanent I added the following to /etc/rc.local:
/sbin/modprobe -r psmouse
/sbin/modprobe psmouse
See <https:/ /bugs.edge. launchpad. net/ubuntu/ +source/ linux/+ bug/191024/ comments/ 40>