Controlling Logitech Litra Glow on CachyOS Arch
It's been a while since I got a Logitech Litra Glow USB light for my desk setup, and I wanted to control it directly from my CachyOS Arch system. Fortunately, there are some great open-source tools available in the AUR - litra and litra-autoglow. You learn something new every day. At some point I was afraid that I would never be able to control my light, but the community proved me wrong.
Installing litra
The litra package provides a command-line tool to control Logitech Litra devices. Installation is straightforward with paru:
1paru -S litra
Once installed, you can control your light with simple commands:
1litra on # Turn the light on
2litra off # Turn the light off
3litra brightness -v 50 # Set brightness (0-100)
4litra temperature -v 3500 # Set color temperature in Kelvin
You can check your connected devices with:
1litra devices

Adding litra-autoglow
To make things even better, I also installed litra-autoglow, which automatically adjusts the light based on your system's ambient light sensor or time of day:
1paru -S litra-autoglow
You can enable it as a systemd user service to have it run automatically:
1systemctl --user enable --now litra-autoglow
Permissions
If you run into permission issues accessing the USB device, you might need to add a udev rule. The litra package should handle this automatically, but if needed, you can check the device permissions:
1lsusb | grep Litra
Yaay!