Multiple issues with external monitor

Help
1

Hi y’all, I’m having some issues with an external monitor.

First off, here’s the output of kinfo:

Operating System: Fedora Linux 43
KDE Plasma Version: 6.5.5
KDE Frameworks Version: 6.22.0
Qt Version: 6.10.1
Kernel Version: 6.18.5-200.fc43.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 8 × 11th Gen Intel® Core™ i5-1145G7 @ 2.60GHz
Memory: 16 GiB of RAM (15.3 GiB usable)
Graphics Processor: Intel® Iris® Xe Graphics

Now, as for the problems:

  1. No brightness control whatsoever when using a dock.
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    If I plug the monitor directly to the computer rather than the dock, this issue does not occur.
  2. Monitor doesn’t work when closing the laptop lid. Happens regardless of using a dock or not. When connected to the monitor, I should be able to close the lid to use the monitor only, however what happens is that the monitor gets no signal and goes on standby, and upon opening the lid again, I see the login screen.
    Here are my power settings:
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    Even if I change the “When laptop lid closed” option to “Do nothing”, with or without the “Even when an external monitor is connected” checkbox, the issue still occurs.
    I looked at the journalctl logs and found the following after closing and opening the lid, if that’s any help:
jan 22 11:31:44 fedora plasmashell[2028]: There are no outputs - creating placeholder screen
jan 22 11:31:44 fedora plasmashell[2028]: requesting unexisting screen available rect -1
jan 22 11:31:51 fedora plasmashell[2028]: There are no outputs - creating placeholder screen
jan 22 11:31:51 fedora plasmashell[2028]: requesting unexisting screen available rect -1

That’s about it, any help would be much appreciated!

2

did it work once in the past ?

3

Never did as far as I know, I only got this dock just recently. It does however work fine when plugging the HDMI directly into the laptop.

4

That’s odd.. I have almost exactly your harware setup and the features you are talking about work fine for me.

Operating System: Arch Linux 
KDE Plasma Version: 6.5.5
KDE Frameworks Version: 6.22.0
Qt Version: 6.10.1
Kernel Version: 6.18.6-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 14 × Intel® Core™ Ultra 7 155U
Memory: 32 GB of RAM (30.8 GB usable)
Graphics Processor: Intel® Graphics

My monitor is connected via USB-C and my “Display Configuration” screen looks like this:

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I need to enable the “control hardware brightness with DDC/CI” for brightness control to work.

Also, I get this message about closing the lid when the monitor is connected:

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What do your screens say?

5

Nonetheless, that might be a compatibility issue outright, not a bug in Plasma.

6

Yeah the brightness thing I can attribute to getting a cheap white brand dock from Amazon, and it’s not that big a deal.

The sleep and screen locking thing is independent of that though I think, since it happens with a direct connection too. My Power and Battery panel says the exact same thing as yours: automatic, and configured not to sleep while an external monitor is connected.
Even if I manually block, the screen still locks.

By the way, my laptop is a Thinkpad, if that’s any relevant. Maybe some BIOS setting I don’t know about?

7

hmm… I have a ThinkPad X13 Gen 5, so same brand. And usually, Lenovo has been very great with Linux, haven’t used anything else for years. I bought it without preinstalled OS which as it seems, has some sort of impact on the BIOS too (or at least on the preset defaults, e.g. Secure Boot).

I will check tonight if I have some BIOS options for power management which might be about the “do not lock with external display” feature.

8

I have checked yesterday and couldn’t find anything related to this issue in my BIOS.

Did you make some progress maybe? Some new insights? Does it happen with other monitors? Do you have a LTS kernel you can try with?

9

Hi, thanks for checking on my behalf. I tried plugging my laptop to a TV and sure enough, it worked perfectly, I could close the lid just fine! So it turns out it’s a compatibility issue with my monitor I guess.
My monitor is an MSI Pro MP model for reference. I’ll try messing with the monitor settings and see if that does anything.