[SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

TheFrostyFungai · 2024-06-17 10:28:43

Hello everyone,

I'm having an issue with my ThinkPad where the Ctrl and Alt keys are not being detected in KDE Plasma (Wayland) on my Arch Linux installation.

Here are the details of my setup and the steps I've taken so far:

System Information:

Laptop Model: ThinkPad T430
OS: Arch Linux (latest updates applied)
Desktop Environment: KDE Plasma (Wayland)

Problem Description:
The Ctrl and Alt keys do not seem to register any input when pressed. This issue occurs specifically in the KDE Plasma (Wayland) session. Both keys work fine in other desktop environments like X11.

Steps Taken So Far:

Checked the keyboard settings in KDE System Settings, but found no issues.
Tried different keyboard layouts to see if that resolves the issue.
Looked through relevant logs (e.g., journalctl, dmesg) but didn't find anything that stood out.

I tried xev & showkey. both dont show up any events for these keys.

If anyone has encountered a similar issue or has suggestions on how to troubleshoot this further, your help would be greatly appreciated.

EDIT* I thought I should mention the keyboard sequence (left to right) = Fn, Ctrl, Win, Alt, [Space], Alt, PrtSc, Ctrl

Thank you

Last edited by TheFrostyFungai (2024-06-19 07:47:32)

polyfish0 · 2024-06-17 13:33:45

Do you have enabled the FN/CTRL swap in your BIOS enabled without knowing it?

TheFrostyFungai · 2024-06-17 13:55:18

I had checked that BIOS option as it is not enabled. Thanks for replying though. Im at a loss as to why these button events are not triggered.

seth · 2024-06-18 16:33:19

Please don't DM me for attention.

This issue occurs specifically in the KDE Plasma (Wayland) session. Both keys work fine in other desktop environments like X11.

To be absolutely clear: this includes plasma on X11? Keys work as expected there as well?
Also ctrl and alt by themselves don't do a lot - how excatly do you measure their disfunction? (Some specific shortcut)?
Does KDEs shortcut assignment UI pick them up?
Does ctrl+alt+F3 still allow you to change the VT?

I tried xev & showkey. both dont show up any events for these keys.

What you want to look at are

sudo libinput debug-events
sudo evtest

xev reports on xwayland and showkey is for the console.
Since it works in X11 sessions I'll bet your right arm that at least evtest will produce output?

Tried different keyboard layouts to see if that resolves the issue.

How do you set those?

TheFrostyFungai · 2024-06-18 19:33:19

Sorry I just really wanted your attention.

To be absolutely clear: this includes plasma on X11? Keys work as expected there as well?

Just to be clear I am an absolute noob. And no not X11 on plasma. but perfectly on other X11 distros I dare not mention here.

Also ctrl and alt by themselves don't do a lot - how excatly do you measure their disfunction? (Some specific shortcut)?

I'm measuring the dysfunction of the Ctrl and Alt keys by attempting to use common shortcuts (e.g., Ctrl+C for copy, Ctrl+Alt+T for opening a terminal)

Does KDEs shortcut assignment UI pick them up?

No

Does ctrl+alt+F3 still allow you to change the VT?

No

What you want to look at are
sudo libinput debug-events

Nothing

sudo evtest

Nothing

xev reports on xwayland and showkey is for the console.
Since it works in X11 sessions I'll bet your right arm that at least evtest will produce output?

I wish but no

Tried different keyboard layouts to see if that resolves the issue.
How do you set those?

Via both the KDE UI settings and the terminal

Last edited by TheFrostyFungai (2024-06-18 19:37:23)

seth · 2024-06-18 19:49:42

but perfectly on other X11 distros I dare not mention here.

So you didn't test it on your arch installation with some other desktop environment but on some completely different (live?) distro?

attempting to use common shortcuts

Is a rather fragile test.
Boot the multi-user.target (2nd link below) and there run "sudo evtest", select the proper device (test everyone that looks relevant) and press the left control key - do you get any response and is it KEY_LEFTCTRL?

TheFrostyFungai · 2024-06-18 20:20:30

So you didn't test it on your arch installation with some other desktop environment but on some completely different (live?) distro?

Well only live distro was tails and it was happy with the keys. I tend to do physical installs, they all work no issue.

Boot the multi-user.target (2nd link below) and there run "sudo evtest", select the proper device (test everyone that looks relevant) and press the left control key - do you get any response and is it KEY_LEFTCTRL?

Forgive my ignorance this command does require a device parameter. I chose 5 for “Extra Buttons”. and also tried "3" for AT translated set 2 keyboard. I see nothing for the L or R Ctrl keys under this condition. However to verify im running this I selected left arrow key and I was provided with
Type 4(EV_MSC) code 4 (MS_SCAN) value cb, type 1 (EV_KEY_, code 105 (KEY_LEFT), value 0

seth · 2024-06-18 20:26:08

So the key doesn't make it into evdev - try the behavior of the LTS kernel.

TheFrostyFungai · 2024-06-18 20:36:08

I installed the linux-lts and linux-firmware-lts just now. booted into terminal for LTS. tried the above and now im stuck as I cant use Ctrl+C to kill the test.

Just done a hard reset. but it is odd the kernel knows other specific keys such as Mute, Vol up/down, Pwr btn etc which are outside of the main keyboard range.

Last edited by TheFrostyFungai (2024-06-18 20:36:50)

seth · 2024-06-18 20:38:33

There's no "linux-firmware-lts", what exact distro are you running?

TheFrostyFungai · 2024-06-18 20:39:07

I have zero issues with Arch KDE wayland on my gaming rig or my other desktop. Its just my Thinkpad T430 and I do like this machine.

TheFrostyFungai · 2024-06-18 20:39:37

There's no "linux-firmware-lts", what exact distro are you running?

Sorry I mean "linux-lts linux-lts-headers"
and for the record I can install Mint, Ubuntu, Fedora out of box with no key concerns on the T430

Last edited by TheFrostyFungai (2024-06-18 20:41:46)

seth · 2024-06-18 20:40:31

tried the above and now im stuck as I cant use Ctrl+C to kill the test

Errr… you could on the main kernel??

TheFrostyFungai · 2024-06-18 20:42:26

I could but I was upset

seth · 2024-06-18 21:03:10

What means the ctrl key works on the main kernel??
Do you have an external keyboard you can attach so you can use the system in a more sensible way?

If it's not the kernel, the most likely contender is udev/systemd - try to downgrade that.
Also when was the last time you ran a different/working distro on the system? (To rule out an emerging HW problem since your descritptions so far do not really add up to a deterministic behavior)

TheFrostyFungai · 2024-06-19 05:43:04

It didnt work on the main Kernel

When I plug in external keyboard everything is fine.

udev/systemd - try to downgrade that.

This is something I havnt tried yet and will later today.

As you mentioned I will also test for any HW fault by installing another distro.

Many thanks for your support so far it is appreciated

TheFrostyFungai · 2024-06-19 07:44:47

You were right Seth it was a hardware fault. In truth I was running mint just before I installed Arch and everything was fine.
I reverted back to mint to test and same outcome

Happened a few people it seems
https://forums.lenovo.com/t5/Lenovo-Ide … -p/5077095

I reseated the keyboard ribbon but still these keys dont work. The ribbon looks fine, no cracks or hard bends. Anyway ill go look into bios updates, or purchase another keyboard for this model.

Im very sorry to waste time here. I assumed it was a layout or an install error on my behalf as they worked fine before I moved onto this latest distro.

Thank you for your support

Arch Linux

#1 2024-06-17 10:28:43

[SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#2 2024-06-17 13:33:45

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#3 2024-06-17 13:55:18

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#4 2024-06-18 16:33:19

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#5 2024-06-18 19:33:19

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#6 2024-06-18 19:49:42

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#7 2024-06-18 20:20:30

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#8 2024-06-18 20:26:08

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#9 2024-06-18 20:36:08

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#10 2024-06-18 20:38:33

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#11 2024-06-18 20:39:07

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#12 2024-06-18 20:39:37

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#13 2024-06-18 20:40:31

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#14 2024-06-18 20:42:26

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#15 2024-06-18 21:03:10

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#16 2024-06-19 05:43:04

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

#17 2024-06-19 07:44:47

Re: [SOLVED] Ctrl and Alt Keys Not Detected in KDE Plasma (Wayland)

Board footer