The touchpad worked fine for me with the utopic kernel (3.16.0-30). Due to general system stability problems though I upgraded to the current vivid kernel (3.18.0-12), which seems much more stable in terms of no CPU/GPU hangs so far, though the above mentioned touchpad problems happen for me too since I use the 3.18.0-12 one.
The touchpad worked fine for me with the utopic kernel (3.16.0-30). Due to general system stability problems though I upgraded to the current vivid kernel (3.18.0-12), which seems much more stable in terms of no CPU/GPU hangs so far, though the above mentioned touchpad problems happen for me too since I use the 3.18.0-12 one.