Arch Linux

Kyrodin

Member

Registered: 2020-03-21

Posts: 8

Two conflicting touchpads with libinput/xinput

Hey all,

Hope everyone is doing well with all that's going on. I'm tring to understand and diagnose libinput with regards to my touchpad, KDE Plasma, and some apparently conflicting settings or hardware. I believe one of these shouldn't be there and I'm not sure how to go about resolving this. Should I disable a device? Which? How do I ensure KDE/Plasma is able to recognize the correct device? Do I need to be doing this all though X11 conf files?

Below are the touch pad devices as recognized by libinput:

0 0 [ ~ ] 
└── % > sudo libinput list-devices | grep -A 18 -i touch
Device:           SYNA2393:00 06CB:7A13 Touchpad
Kernel:           /dev/input/event14
Group:            6
Seat:             seat0, default
Size:             102x77mm
Capabilities:     pointer gesture
Tap-to-click:     disabled
Tap-and-drag:     enabled
Tap drag lock:    disabled
Left-handed:      disabled
Nat.scrolling:    disabled
Middle emulation: disabled
Calibration:      n/a
Scroll methods:   *two-finger edge 
Click methods:    *button-areas clickfinger 
Disable-w-typing: enabled
Accel profiles:   none
Rotation:         n/a

--
Device:           SynPS/2 Synaptics TouchPad
Kernel:           /dev/input/event10
Group:            12
Seat:             seat0, default
Size:             70x51mm
Capabilities:     pointer gesture
Tap-to-click:     disabled
Tap-and-drag:     enabled
Tap drag lock:    disabled
Left-handed:      disabled
Nat.scrolling:    disabled
Middle emulation: disabled
Calibration:      n/a
Scroll methods:   *two-finger edge 
Click methods:    *button-areas clickfinger 
Disable-w-typing: enabled
Accel profiles:   none
Rotation:         n/a

And we can see two touchpads with xinput as well (ids 18 and 13) below:

0 0 [ ~ ] 
└── % > xinput list  
⎡ Virtual core pointer                          id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad                id=18   [slave  pointer  (2)]
⎜   ↳ SYNA2393:00 06CB:7A13 Mouse               id=12   [slave  pointer  (2)]
⎜   ↳ SYNA2393:00 06CB:7A13 Touchpad            id=13   [slave  pointer  (2)]
⎣ Virtual core keyboard                         id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Power Button                              id=8    [slave  keyboard (3)]
    ↳ Sleep Button                              id=9    [slave  keyboard (3)]
    ↳ Integrated_Webcam_HD: Integrate           id=10   [slave  keyboard (3)]
    ↳ Integrated_Webcam_HD: Integrate           id=11   [slave  keyboard (3)]
    ↳ Intel HID events                          id=14   [slave  keyboard (3)]
    ↳ Intel HID 5 button array                  id=15   [slave  keyboard (3)]
    ↳ Dell WMI hotkeys                          id=16   [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=17   [slave  keyboard (3)]
    ↳ Video Bus                                 id=7    [slave  keyboard (3)]
    ↳ Video Bus                                 id=6    [slave  keyboard (3)]

Here are the two packages I have installed related to libinput: I also ensured that I don't have the xf86-input-synaptics package as detailed in the https://wiki.archlinux.org/index.php/Touchpad_Synaptics page.

0 0 [ ~ ] 
└── % > pacman -Ss libinput
extra/libinput 1.15.4-1 [installed]
    Input device management and event handling library
extra/xf86-input-libinput 0.29.0-2 (xorg-drivers) [installed]
    Generic input driver for the X.Org server based on libinput

KDE Plasma appears to be recognizing SynPS/2 Synaptics TouchPad. Settings altered through the UI impact said device and can be seen with the xinput list-props command, but don't actually take affect on my touchpad / pointer / clicks. I believe this is also related to another issue I'm experiencing with my mouse/touchpad cursor https://bbs.archlinux.org/viewtopic.php?id=253836

Of course, any help or information would be greatly appreciated.

Last edited by Kyrodin (2020-03-24 23:24:35)

eichan

Member

Registered: 2018-01-08

Posts: 31

Re: Two conflicting touchpads with libinput/xinput

Did you find a solution? I'm having a very similar problem, and as a result I can't activate 'tap-to-click' on my touchpad. The touchpad settings GUI on Plasma seems to refer to the wrong one of the two detected touchpads by libinput.

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,665

Re: Two conflicting touchpads with libinput/xinput

You should be able to xinput disable the wrong device(s). Still doesn't explain why they happen in the first place, but this helped as a quick measure.

Last edited by V1del (2020-03-30 07:02:23)

eichan

Member

Registered: 2018-01-08

Posts: 31

Re: Two conflicting touchpads with libinput/xinput

Thank you V1del that worked.

I created /etc/X11/xinit/xinitrc.d/99-touchpad-fix.sh

#!/bin/sh
[ -x /usr/bin/xinput ] &&
    xinput disable 'SynPS/2 Synaptics TouchPad'

And then

 sudo chmod a+x /etc/X11/xinit/xinitrc.d/99-touchpad-fix.sh

That's it, problem half solved.

Only half solved because as V1del says up there, still no idea why Xorg is seeing two touchpads. I struggled way too long with that issue. Now I can rest.

Last edited by eichan (2020-03-31 08:48:40)

Kyrodin

Member

Registered: 2020-03-21

Posts: 8

Re: Two conflicting touchpads with libinput/xinput

I have not, yet, discovered a fix. I suppose here's the dreaded "worst part is...". But the worst part is, the problem sometimes "fixes itself" throughout normal use. What I mean is that over the course of a few days of use eventually the correct input device becomes primary and settings like Tap-to-Click and Natural Scrolling are respected.

I can disable the device just as eichan has done, as recommended by V1del, but that doesn't seem to have an effect on which device is currently being recognized.

I will continue to observe and try to pinpoint why it "fixes itself".

sylsau

Member

Registered: 2020-08-09

Posts: 1

Website

Re: Two conflicting touchpads with libinput/xinput

Hello good sir,

Did you fix your completely problem?
So as I understand, you have just one touchpad which seems to pop twice in `xinput` under two different names and it causes conflict, right?
I'd try to look into what's happening in `/usr/share/X11/xorg.conf.d/*` and `/etc/X11/xorg.conf.d/*` and maybe add a rule to disable the 'wrong' one (I'd disable `SYNA2393:00 06CB:7A13 Touchpad`).

ameyngangal

Member

From: India

Registered: 2023-03-02

Posts: 6

Re: Two conflicting touchpads with libinput/xinput

Hello,
I don't know what causes this issue, but I've found this simple solution.
To identify which one is the actual touchpad -

 $ sudo libinput debug-events 

And start moving the mouse around
You'll see many events populate your terminal
The log will show something like this -

 event13  POINTER_MOTION          +20.539s	 -5.28/ -0.88 ( -6.00/ -1.00) 

The device that is active is the one with the matching event ID i.e. 13 in my case

I too have 2 devices listed -

 $ sudo libinput list-devices 
Device:           SYNA32B8:00 06CB:CE7D Mouse
Kernel:           /dev/input/event12
---
Device:           SYNA32B8:00 06CB:CE7D Touchpad
Kernel:           /dev/input/event13
---

Out of which

/dev/input/device12 -- doesn't seem to do anything
/dev/input/device13 -- seems to be the actual device