Same problem on an Asus UX331U. In Ubuntu 18.04 setting kbd backlight worked, it's broken in Ubuntu 18.10.
Oct 1 17:43:19 avis gsd-power[2143]: gsd_power_backlight_abs_to_percentage: assertion 'max > min' failed i am able to manually control the backlight on the shell using sudo tee /sys/class/leds/asus\:\:kbd_backlight/brightness <<< 3 (replace 3 with [0..3] for brightness levels) ----------------------------------- rephlex@avis:[/proc]: ls /sys/class/leds/ asus::kbd_backlight asus::lightbar asus-wireless::airplane input4::capslock input4::numlock input4::scrolllock phy0-led ----------------------------------- root@avis:/sys/class/backlight# ls -la /sys/class/backlight/intel_backlight lrwxrwxrwx 1 root root 0 Okt 1 17:44 /sys/class/backlight/intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight root@avis:/sys/class/backlight# ls -la /sys/class/backlight/ insgesamt 0 drwxr-xr-x 2 root root 0 Okt 1 17:44 . drwxr-xr-x 70 root root 0 Okt 1 17:40 .. lrwxrwxrwx 1 root root 0 Okt 1 17:44 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight ------------------------------------ -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/1788021 Title: changing keyborad brightness doesn't work Status in gnome-settings-daemon package in Ubuntu: New Bug description: Checking 'journalctl' I get this error message: <date> <hostname> gsd-power[1924]: gsd_power_backlight_abs_to_percentage: assertion 'max > min' failed Running on an Asus UX490UA (7th-gen Intel CPU), and before upgrading to 18.10 everything worked fine ProblemType: Bug DistroRelease: Ubuntu 18.10 Package: gnome-settings-daemon 3.29.90.1-1~ubuntu1 ProcVersionSignature: Ubuntu 4.17.0-7.8-generic 4.17.12 Uname: Linux 4.17.0-7-generic x86_64 ApportVersion: 2.20.10-0ubuntu7 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Mon Aug 20 21:22:13 2018 InstallationDate: Installed on 2018-08-15 (5 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) SourcePackage: gnome-settings-daemon UpgradeStatus: Upgraded to cosmic on 2018-08-20 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-settings-daemon/+bug/1788021/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
