gaomon-s620.tablet file do exist but do not apply on the tablet

[kuromaku7]

• Device name: GAOMON S620

• Device model identifier:

• libwacom version: 2.16.1

• I understand that libwacom does not affect whether the device works (see Troubleshooting)

libwacom-list-local-devices output:

/dev/input/event8 (usb:256c:006d - "GAOMON Gaomon Tablet Dial") is a tablet but not supported by libwacom
/dev/input/event7 (usb:256c:006d - "GAOMON Gaomon Tablet Touch Strip") is a tablet but not supported by libwacom
/dev/input/event6 (usb:256c:006d - "GAOMON Gaomon Tablet") is a tablet but not supported by libwacom
/dev/input/event5 (usb:256c:006d - "GAOMON Gaomon Tablet") is a tablet but not supported by libwacom
Failed to find any devices known to libwacom.

For some reason, there is multiple input devices called "gaomon tablet". But none of them was recognized by libwacom.
Part of cat /proc/bus/input/devices output:

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0002/input/input8
U: Uniq=OEM02_T18e_200919
H: Handlers=mouse2 event5 
B: PROP=1
B: EV=1b
B: KEY=1c01 0 0 0 0 0
B: ABS=d000003
B: MSC=10


I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0002/input/input9
U: Uniq=OEM02_T18e_200919
H: Handlers=event6 js0 
B: PROP=0
B: EV=1b
B: KEY=800 201ff 0 0 0 0
B: ABS=3
B: MSC=10

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet Touch Strip"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0002/input/input10
U: Uniq=OEM02_T18e_200919
H: Handlers=event7 js1 
B: PROP=0
B: EV=b
B: KEY=1 0 0 0 0
B: ABS=1000000001b

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet Dial"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0002/input/input11
U: Uniq=OEM02_T18e_200919
H: Handlers=mouse3 event8 js2 
B: PROP=0
B: EV=1f
B: KEY=1 0 0 0 0
B: REL=900
B: ABS=10000000003
B: MSC=10

gaomon-s620 looks like

[Device]
Name=GAOMON S620
ModelName=
DeviceMatch=usb|256c|006d|GAOMON Gaomon Tablet Pen;usb|256c|006d|GAOMON Gaomon Tablet Pad;usb|256c|006d|GAOMON Gaomon Tablet Pen|OEM02_T18e;usb|256c|006d|GAOMON Gaomon Tablet Pad|OEM02_T18e;
Width=6
Height=4
Layout=gaomon-s620.svg
IntegratedIn=
Styli=@generic-no-eraser;

[Features]
Stylus=true
Reversible=true

[Buttons]
Left=A;B;C;D
EvdevCodes=BTN_0;BTN_1;BTN_2;BTN_3

Bug description

[whot]

See this blogpost of mine which explains why you have so many devices. What you're seeing is a UI issue, we need to figure out how to filter those better in GNOME settings but functionally it shouldn't be an issue.

libwacom does the right thing here afaict.

[whot]

no wait, I stand corrected: Failed to find any devices known to libwacom.

This shouldn't happen, the main device should still be detected but for some reason it doesn't have the Pen and/or Pad suffix that the libwacom matches require. Did this recently break?

[kuromaku7]

Did this recently break?

Yes, this is a recent problem. A couple of months ago, the buttons on my Gaomon S620 tablet worked correctly, and I was able to assign custom key combinations to them. Now, it's no longer possible. I found in GNOME's that it will define any unknown tablet as having no buttons and a pen with only two buttons. I also recall that in the settings, my tablet was previously correctly identified as "Gaomon S620," but now it only shows a generic "Gaomon Tablet."

[whot]

That would indicate a change in the kernel, the names you see are taken as-is from the kernel so an changes indicate (in this case) a change in the hid-uclogic driver in the kernel. If you can I recommend testing a kernel from when it worked to verify.

[kuromaku7]

@whot
yup, problem not occurs after downgrading to kernel-6.14.0-63.fc42

Problem appears in
6.17.4 kernel
6.16.12 kernel

[kuromaku7]

Should I fill a bug in the linux kernel repo about broken user space or it's libwacom problem?

[whot]

The kernel changed how the devices are named and we rely on that name for identification. But the device name is not really stable API for the kernel so it's not definitive who's problem it will be. What about the 6.15 kernel, can you reproduce with that? Ideally we can narrow down as much as possible to figure out what changed this.

[kuromaku7]

6.15.10 problem occurs
6.14.11 problem occurs
6.14.6 problem do not occurs
6.14.7 marked as obsolete in koji for fedora linux, unable to install
6.14.8 problem do occurs

btw, this is normal output of cat /proc/bus/input/devices when problem do not ocurs:

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet Pen"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0004/input/input11
U: Uniq=OEM02_T18e_200919
H: Handlers=mouse2 event8 
B: PROP=1
B: EV=1b
B: KEY=1c01 0 0 0 0 0
B: ABS=d000003
B: MSC=10

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet Pad"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0004/input/input12
U: Uniq=OEM02_T18e_200919
H: Handlers=event9 js0 
B: PROP=0
B: EV=1b
B: KEY=800 3ff0000000003ff 0 0 0 0
B: ABS=3
B: MSC=10

I: Bus=0003 Vendor=256c Product=006d Version=0111
N: Name="GAOMON Gaomon Tablet Touch Strip"
P: Phys=usb-0000:00:1d.0-1.5/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/0003:256C:006D.0004/input/input13
U: Uniq=OEM02_T18e_200919
H: Handlers=event10 js1 
B: PROP=0
B: EV=b
B: KEY=1 0 0 0 0
B: ABS=1000000001b

[kuromaku7]

I have renamed DeviceMatch parameter like a user in #914 by Simply replacing the old names GAOMON Gaomon Tablet Pen and GAOMON Gaomon Tablet Pad with the new GAOMON Gaomon Tablet in the gaomon-s620.tablet configuration file, loading it to /etc/libwacom, loading gaomon-s620.svg to /etc/libwacom/layouts and running libwacom-update-db /etc/libwacom. And viola, my tablet works again.
Can we create a new separated gaomon-s620.tablet file to resolve the issue and keep backward compatibility?
My config file:

gaomon-s620-new.txt