Linux is detecting a pen eraser even though tablet/pen doesn't have one

sixtyfouroftheclock

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For some reason this linux is detecting an eraser when I use my tablet (it doesn't have an eraser. It's a Gaomon S620)
It's OK detecting an eraser since it's not really annoying me, but I can't use the 2nd button of my pen because this button is being detecting as the eraser. I mean I can't map this button to be the middle click (this is what I want)

1758773014157.png


I'm not really sure what the correct way to check these events is, but I'm using this
Code:
>sudo libinput debug-events | grep eraser                                                                                                                                                                                           0:43:27
 event3   TABLET_TOOL_PROXIMITY        +1.596s          42.10*/33.65*   tilt: 0.00*/0.00*       pressure: 0.00* eraser   (0, id 0) proximity-in axes:pt btn:S
 event3   TABLET_TOOL_PROXIMITY        +2.257s          42.39 /33.33    tilt: 0.00 /0.00        pressure: 0.00  eraser   (0, id 0) proximity-out

And I think this is for the tip
Code:
>sudo libinput debug-events | grep down                                                                                                                                                                                             0:50:55
 event3   TABLET_TOOL_TIP              +0.053s          72.72*/49.03*   tilt: 0.00 /0.00        pressure: 0.17* down

What should I do? I'm really lost
 


G'day @sixtyfouroftheclock and welcome to linux.org

I can't help you myself, but a couple of points to help those who may be in a position to help -

1. What distro and version are you using, eg Ubuntu 24.04 or other?
2. I am moving this to Laptops/Netbooks where tablets inquiries are best placed.

Good luck

Chris Turner
wizardfromoz
 
G'day @sixtyfouroftheclock and welcome to linux.org

I can't help you myself, but a couple of points to help those who may be in a position to help -

1. What distro and version are you using, eg Ubuntu 24.04 or other?
2. I am moving this to Laptops/Netbooks where tablets inquiries are best placed.

Good luck

Chris Turner
wizardfromoz
Thanks for answer me @wizardfromoz : )

I'm using Arch Linux on an old desktop.
I think you didn't understand my question. I'm trying to use a graphics tablet like wacom, not a laptop device nor a tablet with a display.

Let me explain my trouble again:

---
When I plug a graphics tablet (it's not a Wacom, it's a Gaomon) and press the 2nd button of my pen it's recognized as an eraser. I can't even customize this button, it's stuck as an eraser. This is not good.

It's only this button that acts weird, the rest works fine as they should.
---

Furthermore I've been using OpenTabletDriver to resolve this problem since I moved to Linux 2 years ago. However, I know Gnome is going to unsupport X11, and because of that I don't want to use OpenTabletDriver anymore. It's a great program, but my experience with it in Wayland hasn't been good with a couple problems. It works perfectly in X11.

May I ask you if something is unclear? It's annoying that I can't use the 2nd button.
 
There is a thread here, from 18 months ago which might provide you with some ideas

https://www.linux.org/threads/linux-and-gaomon-s620-the-pen-doesnt-draw.48984/

Perhaps you might have to consider using something other than Arch.

Ubuntu Desktop is GNOME based, but both Xubuntu (Xfce desktop) and Kubuntu (KDE) support X11.

CentOS 10 Stream may support the Gaomon.

Whether these will recognise the pen I cannot guess.

HTH

Wizard
 
Whether these will recognise the pen I cannot guess.
I had a look, starting from the above linked previous issue. The issue is the GAOMON vendor (and others) sell different devices with the same product ID. The combo "vendor ID : product ID" is needed by the USB subsystem to select drivers. Hence, automatic detection breaks and DE like GNOME which have integrated GUI to configure device parameters don't show the correct options (i.e. no two buttons).

This problem is independent of X11 or Wayland backend (easier to work-around in X11), i.e. I don't think another distro makes a difference (none can guess the ideal product ID to best compat, bc there is no 1:1 match).

The linked DIGImend repo in above old thread enables a work-around to use wacom drivers for the devices (different vendor) and selectively match a product. It could indeed be a good solution. Another tool to replace OpenTabletDriver for Wayland appears to be https://github.com/sezanzeb/input-remapper
 


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