Several months ago, I upgraded a Lenovo Thinkpad 11e laptop from 16.04 to 18.04. From the start, I had some issues with the mouse/trackpad (after suspend/resume, click and drag wouldn’t work properly until a full reboot, which oddly often hanged and required a hard restart), but those issues went away after a later update.
Now, however, I’ve noticed a new bug. The laptop’s trackpad becomes unresponsive when the laptop is on battery power. It works normally as long as the ac adapter is plugged in. If I unplug it, the trackpad ceases to work. If I plug it back in, it will work again. An external USB mouse continues to work normally.
Running $ cat /proc/bus/input/devices shows this, which I’m pretty sure is the touchpad:
I: Bus=001d Vendor=06cb Product=0000 Version=0000
N: Name="Synaptics s3203_ver5"
P: Phys=rmi4-00/input0
S: Sysfs=/devices/rmi4-00/input/input9
U: Uniq=
H: Handlers=mouse0 event7
B: PROP=15
B: EV=b
B: KEY=e520 10000 0 0 0 0
B: ABS=6f3800001000003
and running $ xinput --list shows
|⎡ Virtual core pointer |id=2|[master pointer (3)]|
|---|---|---|
|⎜ ↳ Virtual core XTEST pointer |id=4|[slave pointer (2)]|
|⎜ ↳ Synaptics s3203_ver5 |id=13|[slave pointer (2)]|
|⎜ ↳ PixArt USB Optical Mouse |id=14|[slave pointer (2)]|
|⎣ Virtual core keyboard |id=3|[master keyboard (2)]|
| ↳ Virtual core XTEST keyboard |id=5|[slave keyboard (3)]|
| ↳ Power Button |id=6|[slave keyboard (3)]|
| ↳ Video Bus |id=7|[slave keyboard (3)]|
| ↳ Power Button |id=8|[slave keyboard (3)]|
| ↳ Sleep Button |id=9|[slave keyboard (3)]|
| ↳ Integrated Camera: Integrated C |id=10|[slave keyboard (3)]|
| ↳ AT Translated Set 2 keyboard |id=11|[slave keyboard (3)]|
| ↳ ThinkPad Extra Buttons |id=12|[slave keyboard (3)]|
I tried booting up the laptop from an UM 16.04 usb key, and the trackpad worked normally on and off AC power, so I know it is not a hardware issue.
Has anyone had a similar issue on 18.04? Any tips on how to get the trackpad working on battery again? I’m thinking of filing a bug report, but I’m not that familiar with the process yet.