Displaylink
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DisplayLink monitors
In order to use Displaylink monitors over USB, such as the ASUS MB16AC, the displaylink driver needs to be installed:
$ services.xserver.videoDrivers = [ "displaylink" "modesetting" ];
The module `nixos/modules/hardware/video/displaylink.nix` should also work for wlroots compositors.
Since these drivers depend on binary unfree blobs, you will need to first add it to your nix-store. Go to https://www.displaylink.com/downloads/ubuntu to get the appropriate driver version and note the download URL you get after accepting the EULA. The currently expected version for the driver can be found under: https://www.synaptics.com/products/displaylink-graphics/downloads/ubuntu-5.8?filetype=exe.
Then (example):
$ nix-prefetch-url --name displaylink-600.zip https://www.synaptics.com/sites/default/files/exe_files/2024-05/DisplayLink%20USB%20Graphics%20Software%20for%20Ubuntu6.0-EXE.zip
Connecting a second external monitor
In order to add a second external monitor you can add the following to your configuration:
services.xserver.displayManager.sessionCommands = ''
${lib.getBin pkgs.xorg.xrandr}/bin/xrandr --setprovideroutputsource 2 0
'';