Dear Maintainers,

Screen backlight is not working on my Samsung N150 with Debian 13.

After searching for possible solutions, I found a 2022 article from
Hans de Goede explaining that he changed a lot of things on the
backlight control for 6.1, so I made tests with kernel packages from
snapshot.debian.org (see
https://web.archive.org/web/20221107140732/https://hansdegoede.livejournal.com/26427.html).

Indeed, if I boot with linux-image-6.0.0-5-amd64-unsigned (6.0.10-2),
`/sys/class/backlight/intel_backlight/` exists, and I can control
screen brightness with `/sys/class/backlight/intel_backlight/brightness`.

And, if I boot with a newer kernel, from linux-image-6.1.0-0-amd64-unsigned
(6.1~rc3-1~exp1) to linux-image-6.18.3+deb14-amd64-unsigned (6.18.3-1),
`/sys/class/backlight/` only contains the directory `samsung`, which does not
allow controlling the screen.

Do not hesitate to ask if you want me to make some tests or if I can provide
more information.

Regards,
Yvan

Here is attached the data asked by Hans de Goede in his blog post. This
data has been collected while running Linux 6.0, so with a functional
backlight control.

Again, do not hesitate to ask if I can help in any way