How do I enable changing the backlight brightness on my laptop? (Kubuntu)

Sky

5/27/24, 2:30 PM

I recently installed Kubuntu 22.04 with KDE on my Pixelbook (2017), and the backlight of the monitor either is at maximum brightness, or off.

I have tried manually changing values in /sys/class/backlight/intel_backlight/brightness, which changes the value in actual_brightness. The only time it changes my screen brightness is when it is set to 0, in which case it turns off.

I have tried changing the GRUB_CMDLINE_LINUX_DEFAULT setting in etc/default/grub to include various forms of intel_backlight=vendor, 0, default, etc., or acpi_backlight= \<various values>, and acpi_osi=linux. I then run the command sudo update-grub, followed by a reboot to no change.

Currently, my workaround is using Display Brightness Control, which allows setting the brightness below the minimum. When it is set below the minimum, it does affect the brightness, but I am unable to use the brightness keys to adjust the brightness, which I would prefer.

The brightness control does pop up on my screen when I adjust the brightness normally, showing that the software and brightness keys are responding properly, but any value between 1% and 100% appears the same. When using Display Brightness Control, the pop up shows 0% when adjusting the brightness in the adjustable region (below the usual minimum).

I have tried solutions suggested in upwards of a dozen similar questions, but none have worked, hence me creating a new question. Feel free to point me towards other posts though, in case I have missed one that may work.

0 + 2

backlight

laptop

brightness

kubuntu

screen

richbl

5/28/24, 2:55 AM

**Welcome to the Ask Ubuntu community.** First, please edit your question to include the version of the Kubuntu OS that you're running. Also, you mentioned that you tried over a dozen suggested solutions, but you don't identify which solutions you tried. I suspect you may end up getting dupes of those solutions, as you haven't really explained what specifically you tried (even links to solutions would be helpful). Thanks

Sky

5/29/24, 9:27 PM

Thank you. I have added the Kubuntu version number of 22.04. The solutions I could find largely revolved around changing the values in the etc/default/grub file, which I described in my question. I will try to find those solutions and list specifically what I have attempted.

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EN: How do I enable changing the backlight brightness on my laptop? (Kubuntu)

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