Brightness changing, since Kernel 6.17+

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Hello there,

I have Lenovo Legion S7 15ACH6 model 82K8006CCK. I have installed Fedora 42 with KDE like year ago (it is not Kinoite).

There then were several Kernel updates, last Kernel version where brightness changing worked correctly was 6.16.12-200 (to degree, it was working if I was running on charger, not on battery but that was fine, I think when on battery only AMD gpu was handling brightness change it did nothing but on charger NVIDIA gpu was handling brightness so it worked), then there came update to kernel 6.17 then 6.19 etc. When I am using Fn keys or panel menu slider for brightness in KDE it moves but brightness never changes actually. I tried to troubleshoot it by using acpi backlight args to grubby (like native, video, etc.), did not help at all.

Also laptop has hybrid gpu AMD iGPU+Nvidia dGPU. I have installed Nvidia driver from rpmfusion.
I did dnf versionlock kernel 6.12.16-200 so I could always return to it when there were new kernel updates but I was not aware that when I upgrade to Fedora 43 from Fedora 42 it will remove that Kernel nonetheless of versionlock (because upgrade ignores old fc42 packages or something like that what I found out). I did upgrade today as I noticed that Fedora 42 is not supported anymore.

Now I am stuck without ability to change my brightness on laptop at all. I would like to fix this issue without forcing laptop to Nvidia GPU only.
What to do, should I somehow re-download older kernel 6.12.16-200 for Fedora 43 or is there something else to try? Any help would be really appreciated.

inxi -Fzxx and fpaste --sysinfo --print output:

inxi_Fzxx_output

fpaste_sysinfo_output

2

The following post on the Arch Linux forum from Dec 5, 2025 might be useful:

[SOLVED] Legion S7 15ACH6 panel brightness does not change

And something else that might be of interest:

3

Thank you so much that you found this! Actually adding acpi_backlight=nvidia_wmi_ec with command grubby --update-kernel=DEFAULT --args "acpi_backlight=nvidia_wmi_ec" fixed it for me. It’s funny that this option for acpi_backlight I didn’t try then (didn’t know it exist either).