Brightness controls not working

Issues & Assistance
1

Solution at bottom

Hi everyone Day 1 CachyOS user here, and I’m running into an issue where I’m unable to increase or decrease my screen brightness from the slider, on my keyboard, and on the terminal with the light AUR. When i searched for a solution all of them came back with changing lines in /etc/default/grub, but since I’m on systemd-boot I don’t have the files, and I’m unsure what else I could change.

I was wondering what would be an equivalence to /etc/default/grub on systemd-boot so I can somehow get my screen to not blind me whenever a site is on light mode.

Reference solutions:

My hardware/software:

  • My laptop: Lenovo Legion S7 15ACH16
  • DE: KDE Plasma 6.5.4
  • Boot: systemd-boot
  • GPU1: Nvidia Geforce RTX 3060 Mobile / Max-Q
  • GPU2: AMD Radeon Vega Series / Radeon Vega Mo

My solution

Thank you to cscs for pointing me in the right direction!

So when I went to my /boot/loader/entries I had the files for linux-cachyos.conf and linux-cachyos-lts.conf and when I added acpi_backlight=nvidia_wmi_ec to the end of options it didn’t do anything.

I later installed the nvidia open driver from NVIDIA - ArchWiki and then when I went back to the folder I had a new file called linux.conf and this is where I added acpi_backlight=nvidia_wmi_ec and that solved it for me.

Hope this helps new users!

2

Hello and welcome,

If we mean

All of the boot managers have ways to do this;

3

This will not fix your brightness problem but I also got tired of light mode websites, so I wrote a little script that inverts a web page except for the images, videos and iframes.

Usage:

  1. In your bookmark toolbar, create a new bookmark
  2. Name: INVERT
  3. URL:
javascript:(function(){
  var html = document.documentElement;
  var inverted = html.style.filter === 'invert(1)';
  html.style.filter = inverted ? 'invert(0)' : 'invert(1)';
  document.querySelectorAll('img, video, iframe').forEach(el => {
    el.style.filter = inverted ? 'invert(0)' : 'invert(1)';
  });
})();

Now you can click that bookmark to get a temporary “dark mode” everywhere :grin:

4

I ended up needing to download an open driver first and then it created a new linux.conf file in my loader which is where I added acpi_backlight=nvidia_wmi_ec and it fixed it!

5

Just uninstalled DarkReader add-on because it was breaking websites and slowing things down (tested sites in incognito to see difference without add-ons) so discovering your script a few minutes later very timely, thank you!

6

For yet another alternative I may also mention the following;

Which I find to be nicer and slimmer than DarkReader .. though I still keep it off most of the time.

7

Where is this open driver you downloaded?