Bug 488045

Summary:	Touch screen locks up within a handful of inputs (Microsoft Surface Pro 7, NixOS)
Product:	[Plasma] kwin	Reporter:	m1vri31c
Component:	input	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DOWNSTREAM
Severity:	major	CC:	aleixpol, m1vri31c, nate, notmart
Priority:	NOR
Version:	6.0.5
Target Milestone:	---
Platform:	NixOS
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description m1vri31c 2024-06-05 02:13:06 UTC

SUMMARY
Touch screen stops working after just a few inputs. To fix this issue you must use the mouse. I have had the issue with no apps open other than the desktop and the widgets I have. It happens so often the touchscreen is unusable.

I think what is happening is that the touch input becomes “sticky”, with some touches being held after you release your finger, or some sort of invisible mouse cursor freezing. This get reset by mouse input. But it’s hard to tell exactly what is going on.

https://bugs.kde.org/show_bug.cgi?id=438551 looks similar but seems far less severe and is reported as a Dolphin bug.

STEPS TO REPRODUCE
1. Use touchscreen for short amount of time. As far as I can tell any type of touch input can randomly cause the bug, with no discernible pattern
2. Move or click mouse to reset the touchscreen.

OBSERVED RESULT
Touch screen stops receiving input or at least becomes so unresponsive so it seems that way. Sometimes it seems like only the touch input for the window or app you are using stops working but after a moment the whole touchscreen locks up anyway, and I haven't been able to reproduce this.

EXPECTED RESULT


SOFTWARE/OS VERSIONS
NixOS 24.11 (unstable channel)
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.2.0 
Qt Version: 6.7.1

ADDITIONAL INFORMATION
Microsoft SP7 uses the IPTS drivers, and requires a special kernel.

Comment 1 Marco Martin 2024-06-06 11:26:02 UTC

looks like driver issues, does this happen only on plasma?

Comment 2 m1vri31c 2024-06-07 05:17:06 UTC

(In reply to Marco Martin from comment #1)
> looks like driver issues, does this happen only on plasma?

I could not reproduce the issue in Gnome, but that does not mean it doesn't exist, especially since I went back to Plasma and immediately used the touchscreen longer than I've ever been able to in an unbroken tablet mode session and have not encountered the previously VERY common issue since. I guess that's always the way with bugs. Unless uninstalling and reinstalling Plasma has fixed the issue, in which case I will know in a few days if it hasn't happened, and will add a comment saying so.

Comment 3 m1vri31c 2024-06-17 09:05:33 UTC

It seems like uninstalling and re-installing Plasma fixed the issue (very weird especially considering how NixOS works). Worth noting I still get the issue if the Surface keyboard cover is plugged in and the device is on its side but that surely is a driver issue – unplugging and reconnecting the keyboard fixes the touchscreen in that case.

Comment 4 Nate Graham 2024-06-17 13:54:58 UTC

Cool, maybe it was caused by something deeper in the stack.