Bug 508054

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SUMMARY

I recently got a Huion Kamvas 16 Pro, and wish to use all of the functionalities of the tablet, including the touchscreen slider. Issue is that the buttons and the sliders do not work unless I have the app opened. Other Linux applications do not give the touchscreen slider functionality and/or the button slider functionalities on the last button(able to either zoom in/out, brush size, scroll up/down)

Having the app opened causes the pen and cursor to have an offset of 2-3 cm. Or rather, the pen matches the cursor on the bottom-left side of the tablet, then the offset increases as you move the pen away from that position. When I attempt to do the KDE touchscreen calibration with the Huion tablet app and drivers enabled, the calibration process does not identify the tap of the pen on the tablet. Or rather, just the bottom left, top right and/or the bottom right calibration dot.

It is worth noting that using the tablet without the Huion App opened works flawlessly, but do not have the access to the slider functionality. Admittedly, I may have observed issues also with the buttons from the pen also, which I think they were reported already.

Important to note is that the Window selections in the Huion Tablet does not permit you to select the correct screen. All issues seem to be inexistent while using GNOME(as I am using it at the moment due to these specified bugs).

STEPS TO REPRODUCE
1. Install the Huion Drivers(either from the AUR repos or from the official website, or CachyOS repository)
2. Open the Huion app
3. Observe the pen-tablet cursor offset.

OBSERVED RESULT

Using the tablet with the Huion app causes a pen offset of 2-3 cm and also disable the pen buttons.

EXPECTED RESULT

Tablet should work with full functionality, and provide the touchscreen slider functionality. And pen button buttons should be functional.

SOFTWARE/OS VERSIONS
Windows: n/a
macOS: n/a
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Linux 6.15(when I tried it, not sure if latest linux kernel resolves this issue)/ KDE Plasma 6.4.4
KDE Plasma Version: 6.4.4/6.4.8
KDE Frameworks Version: unsure
Qt Version: unsure

ADDITIONAL INFORMATION

I can attempt to replicate the issue by reinstalling KDE back, if required.