Fn + F11 F12 for bightness not working

[sahlouls]

Hi,
After applying the script (maybe before), I can't adjust the brightness anymore.
Any help on how to fix it ?
Thanks

[JackHack96]

This is not related to the script, because it doesn't do anything related to hotkeys.
Does the brightness slider in the settings works?

[sahlouls]

The brightness slider in the settings is not working 😞
For some googling, there are two reasons:

• nouveau.modeset=0 config in GRUB_CMDLINE_LINUX_DEFAULT
• switching to nvidia mode

I'm not sure which is the real cause.

[floturcocantsee]

Are you using the 9570 or the new OLED model? OLED panels aren't controlled by the xbacklight daemon and need an external tool.

[sahlouls]

@floturcocantsee no OLED screen

[JackHack96]

I can't reproduce the bug unfortunately, I have the 9570 with FHD screen...
I would first uninstall all nvidia related things with a strong
sudo apt autoremove --purge nvidia*
Then I would try reinstalling the latest driver which is the 435:
sudo apt install nvidia-driver-435

If it doesn't change anything, I would start fiddling with GRUB and for example delete the nouveau.modeset=0, but it may cause errors...

[notthebee]

I found that I can still control brightness with brightnessctl (available in Ubuntu repositories).
What I personally did is map brightness control keys to brightnessctl s 2000- and brightnessctl s +2000 respectively.
However, by default GNOME doesn't allow mapping media keys, so you will have to change a couple of values in dconf:

dconf write /org/gnome/settings-daemon/plugins/media-keys/screen-brightness-down-static "['']"
dconf write /org/gnome/settings-daemon/plugins/media-keys/screen-brightness-up-static "['']"

After you've done that, reboot and you should be able to map brightness keys.

Alternatively, setting acpi_backlight=native kernel parameter also let me control the brightness in GNOME with no additional tweaks, so maybe that's worth trying out.

[ababino]

Hi,
Same problem here with Ubuntu 19.04. I solved it adding acpi_backlight=native and thinkpad-acpi.brightness_enable=1 to GRUB_CMDLINE_LINUX_DEFAULT. Don't forget to run sudo update-grub for the changes to take effect.

I hope this is useful.

[JackHack96]

Hi,
Same problem here with Ubuntu 19.04. I solved it adding acpi_backlight=native and thinkpad-acpi.brightness_enable=1 to GRUB_CMDLINE_LINUX_DEFAULT. Don't forget to run sudo update-grub for the changes to take effect.

I hope this is useful.

Thank you, I'll report it in the wiki!

[sahlouls]

Thanks @ababino, with this config, the brightness control is working again.
Thanks @JackHack96 for updating the wiki page !