Bug 511936 - Dual touchscreen laptop with touchscreens that have identical device name, vendor ID, and product ID won't map touchscreens uniquely in kcminputrc, requiring remapping on restart
Summary: Dual touchscreen laptop with touchscreens that have identical device name, ve...
Status: REPORTED
Alias: None
Product: kwin
Classification: Plasma
Component: input (other bugs)
Version First Reported In: 6.4.5
Platform: EndeavourOS Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2025-11-10 23:09 UTC by pds3.14
Modified: 2025-11-10 23:09 UTC (History)
1 user (show)

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Description pds3.14 2025-11-10 23:09:31 UTC 
SUMMARY
Vendor id, device name, and product ID are used to specify devices in kcminputrc, which means that identical libinput device names, VIDs, and PIDs cause devices not to be mapped correctly in kcminputrc (though as of KDE 6.5 they are mapped correctly in the GUI settings tool for that session and that session only).

Udev and hwdb rules related to libinput do not seem to resolve the issue

STEPS TO REPRODUCE
1. Find a machine with two identical touchscreens with the same name, VID, PID
2. Note they are mapped incorrectly to displays.
3. Map them correctly in the GUI system settings
4. Restart the device, sleep, or log out and log back in.
5. Note they are mapped incorrectly to displays.

OBSERVED RESULT
KDE Plasma 6.5.2 consistently correctly remaps the touchscreens to the display when using the GUI system settings but not when reading from the kcminputrc it created

EXPECTED RESULT
KDE Plasma 6.5.2 consistently remaps the touchscreens to the display when using the GUI system settings and reading from the kcminputrc it created

SOFTWARE/OS VERSIONS
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: 6.17.7-arch1-1 (64-bit)
KDE Plasma Version: 6.5.2
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0

ADDITIONAL INFORMATION
Wayland and EndeavorOS