touchpad stops generating mouse motion after a while (focal, lenovo yoga c930)

[Chris Kuethe]

Ever since upgrading to focal from eoan, my trackpad stops tracking motion after a while. I'm just mousin' along switching apps and tabs; selecting, cutting, pasting; doing all that usual stuff and suddenly the cursor doesn't move. Tapping on the touchpad generates the expected left- or right-click events. My external mouse still works.

This has happened with kernel 5.4.0-28 and 5.4.0-29; 5.3.0-46 was working just fine.

$ lsb_release -rd
Description: Ubuntu 20.04 LTS
Release: 20.04
$ uname -a
Linux thorium 5.4.0-29-generic #33-Ubuntu SMP Wed Apr 29 14:32:27 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Messing around with the touchpad settings doesn't restore the touchpad to operation, though it can enable/disable the mouse clicks.
Suspend and resume doesn't restore the touchpad.
A reboot fixes the touchpad.

So now, I shall grudgingly reboot. :(

[Chris Kuethe (ckuethe)]

Interestingly, logging in and out again makes the trackpad work, no reboot needed.

$ dpkg -l | grep xorg
ii python3-xkit 0.5.0ubuntu4 all library for the manipulation of xorg.conf files (Python 3)
ii xorg 1:7.7+19ubuntu14 amd64 X.Org X Window System
ii xorg-docs-core 1:1.7.1-1.1 all Core documentation for the X.org X Window System
ii xorg-sgml-doctools 1:1.11-1 all Common tools for building X.Org SGML documentation
ii xserver-xorg 1:7.7+19ubuntu14 amd64 X.Org X server
ii xserver-xorg-core 2:1.20.8-2ubuntu2 amd64 Xorg X server - core server
ii xserver-xorg-input-all 1:7.7+19ubuntu14 amd64 X.Org X server -- input driver metapackage
ii xserver-xorg-input-libinput 0.29.0-1 amd64 X.Org X server -- libinput input driver
ii xserver-xorg-input-synaptics 1.9.1-1ubuntu3 amd64 Synaptics TouchPad driver for X.Org server
ii xserver-xorg-input-wacom 1:0.39.0-0ubuntu1 amd64 X.Org X server -- Wacom input driver
ii xserver-xorg-legacy 2:1.20.8-2ubuntu2 amd64 setuid root Xorg server wrapper
ii xserver-xorg-video-intel 2:2.99.917+git20200226-1 amd64 X.Org X server -- Intel i8xx, i9xx display driver

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1876863/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Chris Kuethe (ckuethe)]

I am totally guessing that it's the synaptics input package is the culprit. I don't see anything in the dmesg that would suggest the kernel is at fault.

[SB (lumumba)]

I am also affected, touchpad stops registering motion now and then. Like every 5 seconds or so.
Worked like a charm before