Comment 5 for bug 1368761

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1342561

I found a workaround which should make the touchpad work in ps/2 mouse emulation mode.

https://bugzilla.redhat.com/show_bug.cgi?id=1110011

You need to add a Kernel Boot Parameter to set the flag i8042.nomux=1 psmouse.proto=bare
which will enable PS/2 Mouse Emulation mode on your touchpad.

Edit your default grub file.

sudo nano /etc/default/grub

Find the line that mentions GRUB_CMDLINE_LINUX and add the flag:

GRUB_CMDLINE_LINUX="i8042.noloop=1 psmouse.proto=bare"

Then save the file and run a grub update.

sudo grub-update

Then restart the system .

product: X750LN
Linux version 3.13.0-36-generic

Distributor ID: Ubuntu
Description: Ubuntu 14.04.1 LTS
Release: 14.04
Codename: trusty