Does Linux support this? I am trying to connect my laptop to a monitor via USB C. The laptop has two Thunderbolt ports and the monitor has support for USB C DP alt mode. I have tested the same setup on my work laptop (windows 11) and it works fine but my laptop running arch does not work. My laptop detects the monitor correctly so it shows up in the KDE plasma display configuration but the monitor is not getting any input. As far as I could tell this is supported in the kernel. Am I wrong? Am I missing some important package?

    • Cralder@lemmy.worldOPEnglish
      1·
      2 days ago

      No I don’t have that installed. Isn’t DisplayLink something completely different?

      Rebooting while connected sorta worked, but not really. When I logged in the laptop monitor went black and the external monitor was black with a white underscore at the top left as if a terminal was open. So that’s something I guess but I could not use my computer at all in this state.

      • lime!@feddit.nuEnglish
        4·
        2 days ago

        yeah displaylink is sort of a streaming feature, but evdi is a kernel module that makes the kernel aware of multiple monitors over usb (among other things), it’s required for display plug-n-play over usb in my experience.

        • progandy@feddit.org
          2·
          1 day ago

          It is not required for the displayport alternate mode of usb-c.

          It is an alternative with limited performance that is built on top of usb and does not require hardware support on the PC side.

          • lime!@feddit.nuEnglish
            1·
            1 day ago

            good to know, i’ve never managed to get it working without. what’s the recommended approach then?

            • progandy@feddit.org
              2·
              15 hours ago

              If your monitor/docking station/adapter and the computer support the DP Alternate mode, then you should use that, it should be supported directly by the kernel. Problems may occur if the port is connected to the dedicated graphics and you use the internal graphics card. In my experience it worked perfectly so I do not know any good troubleshooting steps.

              • lime!@feddit.nuEnglish
                1·
                14 hours ago

                then, maybe it was added to the kernel after i first tried it and i’ve been working with old assumptions.

      • lime!@feddit.nuEnglish
        1·
        2 days ago

        also that behavior is interesting because it means the display is detected and the computer is drawing to it but something in your environment is unstable. check the system log for previous boot to see what screwed up.