Caveat: I'm far from an advanced user. I like Ubuntu for web development and casual use, and generally try to figure things out as the need arises.
After running a routine update (apt update, apt upgrade) and later restarting my ThinkPad Yoga 11e (3rd generation, I believe), my touchpad has stopped working completely. It's listed when I run xinput list, but nothing I've tried so far has managed to restore functionality.
The touchscreen and keyboard still work as expected, and I haven't had a chance yet to test it with Ubuntu booted from a USB stick. –Edit 1: after booting from a USB stick, it appears xinput is showing the wrong device for my touchpad.
Context: at the time it stopped working, I was running 18.04.1 with Unity (ubuntu-unity-desktop), LightDM, and xserver-xorg-input-synaptics. Thinking that Unity and the synaptics driver might have something to do with it, and not getting any helpful search results with so many key phrases, I uninstalled them. Currently running with GNOME, GDM, and xserver-xorg-input-libinput.
–Edit 2: reinstalled Ubuntu and the touchpad worked, then updated and it's back to being completely unresponsive. Prior to updating, xinput list properly showed "SynPS/2 Synaptics TouchPad"; after updating, it once again shows "Synaptics s3203_ver5".
–Edit 3: wiped the drive and reinstalled 16.04. Same results: touchpad worked after installation, failed after updating. Same xinput list results. Reinstalled 18.04 again to start over, and ruled out the kernel as the problem.
Specs:
Ubuntu 18.04.1
GNOME 3.28.2
Kernel 4.15.0-39-generic
Synaptics s3203_ver5 –Edit 1: should be SynPS/2 Synaptics TouchPad
Best Answer
After recent update in 18.04.1 I also start to have issues with not working touchpad and changing brightness with keyboard, this solution for old version of ubuntu fixed it.
To be short, need to add
blacklist ideapad_laptopin your/etc/modprobe.d/blacklist.conffile.