1. Which kernel boot parameters, if any, have you enabled:
cat /proc/cmdline
2. What video cards/drivers are you using:
lspci -k | grep -iA2 VGA
3. What backlight interfaces do you have and what are their values:
for i in /sys/class/backlight/*; do echo $i;cat $i/brightness;cat $i/max_brightness;done
If its just an intel video card that you have, the Intel Graphics wiki suggests editing/creating /etc/X11/xorg.conf.d/20-intel.conf with the following content:
Section "Device"
Identifier "card0"
Driver "intel"
Option "Backlight" "intel_backlight"
BusID "PCI:0:2:0"
EndSection
My backlight works perfectly with "# echo 0~4882 > /sys/class/backlight/intel_backlight/brightness" but when I use hotkeys or change backlight setting in gnome nothing happens because they use /sys/class/backlight/acpi_video0/. How can I make gnome settings to use intel_backlight?
#ls /sys/class/backlight
acpi_video0 intel_backlight
With acpi_backlight=vendor
#ls /sys/class/backlight
intel_backlight sony
also try this acpi script
https://bbs.archlinux.org/viewtopic.php?id=137164
but did not work
"sorry my poor english""
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