I've already tried many solutions I'd found on the web and none of them has worked. I'm using Ubuntu 16.04 LTS, fresh installation.
- This notebook has Intel HD Graphics 5500 and Nvidia GeForce 920M. I thought that installing the proprietary Nvidia driver would solve the issue, but it still exists. Installing
bumblebeefor Nvidia Optimus didn't solve the issue either.
- The other Fn keys like volume up, down, screen off, WiFi etc. work without any problems.
- The brightness keys work in the GRUB selection menu. They stop working immediately after the Ubuntu is selected and launched. On Windows they work perfectly fine.
acpi_listendon't detect the Fn + F5 / F6 combination at all, no matter what solution I try.
intel_backlightfolder and the brightness can be changed using the
sudo tee /sys/class/backlight/intel_backlight/brightness <<< 200command. This folder may also contain a second folder like
acpi_video0after trying some of the solutions, but the brightness setting in this folder does not have any effect.
- Generally, the brightness can be changed in settings or by using
xbacklight, the only issue is that the Fn brightness keys seems to be considered to not exist for the system. EDIT: Apparently,
xbacklightdoesn't work when the Nvidia GPU is used. It works when the Intel GPU is set in Nvidia Prime. So I guess this issue is somehow related to dual GPU setup.
Here are the solutions I've already tried and all of them failed:
- I edited
/etc/default/grubby commenting out the
GRUB_CMDLINE_LINUXline and changing the
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"line. None of the following additions has worked for me, mixed or not:
I created a
/usr/share/X11/xorg.conf.d/20-intel.conffile with the following content:
Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection
It only resulted in a black screen instead of the login screen, so I had to delete this file.
I edited the
/etc/X11/xorg.conffile to add
Option "Backlight" "intel_backlight"and
Option "RegistryDwords" "EnableBrightnessControl=1". This didn't change anything. Here's the actual content of this file:
Section "ServerLayout" Identifier "layout" Screen 0 "nvidia" Inactive "intel" EndSection Section "Device" Identifier "intel" Driver "modesetting" BusID "PCI:0@0:2:0" Option "AccelMethod" "None" Option "Backlight" "intel_backlight" EndSection Section "Screen" Identifier "intel" Device "intel" EndSection Section "Device" Identifier "nvidia" Driver "nvidia" BusID "PCI:4@0:0:0" Option "ConstrainCursor" "off" Option "RegistryDwords" "EnableBrightnessControl=1" EndSection Section "Screen" Identifier "nvidia" Device "nvidia" Option "AllowEmptyInitialConfiguration" "on" Option "IgnoreDisplayDevices" "CRT" EndSection
I can't find any other solutions, just the same as above everywhere. Thanks in advance for any help or ideas what might be a fix.