Brightness

[rygor-thomas]

Does anyone know how to fix the screen brightness ? Every time I log in to my Pc the brightness has gone back to its original setting (about 50%) which is way too bright for my old eyes!
I am using the LXQT version of Spiral Linux on a iMac of 2013 vintage with an i5 processor and 32Gb RAM.
I must congratulate the developer on a very nice distro all round.

[marwenius]

I found a solution on Reddit where one person also had a Macbook:
https://www.reddit.com/r/linuxquestions/comments/b78sta/comment/ejqd1p2/

In the terminal:

sudo nano /etc/default/grub

Find the line GRUB_CMDLINE_LINUX_DEFAULT and add the following within the quotation marks:

acpi_backlight=native

This command must be executed after saving and exiting (CTRL + S, CTRL + X):

sudo update-grub

Then restart (twice if necessary) to test whether the brightness settings are now applied.

This article also deals with this issue:
https://www.reddit.com/r/pop_os/comments/11ok9rs/amdgpu_backlight_failing_to_initialize_macbook/

[geckolinux]

Thanks a lot @marwenius for the helpful response.
Also just a note that SpiralLinux has Grub Customizer pre-installed that allows for easily changing the default kernel parameters.

[rygor-thomas]

Many thanks to you Marwenius. That solved my problem, only not in the way I was expecting, the brightness slider is still at 50% but the backlight slider is now on 0%. At least now I am not dazzled!

[rygor-thomas]

Thanks for your suggestion Marwenius. I will look into this later on and post back.