Fn shortcuts for increase and decrease screen brightness don't work in gnome

Ask Fedora
1

Problem

fn shortcuts for increase and decrease screen brightness don’t work
Cause

Not yet known.

Related Issues

Bugzilla report: #NNNN

Workarounds

None yet.

2

Moving to Ask Fedora …

Please provide more information about your hardware. Has this worked previously with older kernels?

3

I don’t know. I’ve just installed fedora.
I’ve installed gnome extensions to solve this problem and it kinda worked (brightness bar apprared on menu and i’m able to adjust it manually. But i still can’t use fn shortcut for this, even inserting custom shorcuts for these extensions

4

Hello,
without more information we will not be able to tell anything. Gnome is able to recognize functional keys without extensions, so you should be required to install any of them. On my Fedora Workstation 39, I do not have any problems using functional keys on any of my three devices.

Therefore, you need to provide some more information, such as:

  • What is the brand and the type of your computer? Desktop or laptop? Are you using a built-in keyboard or an external keyboard?
  • Which version of Fedora are you using? 39? Earlier? What flavour? Workstation?
  • How did you install Fedora? Did you use Live image or the Netinst method?
  • Are there any errors shown when you examine the journal file? Try using journalctl --boot | grep error.
  • What functional keys are non-operable? All of them? Or just some of them?
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  • What is the brand and the type of your computer? Desktop or laptop? Are you using a built-in keyboard or an external keyboard?
    Acer Nitro 5 ; AN-515-47 ; Laptop; Built-in
    Which version of Fedora are you using? 39? Earlier? What flavour? Workstation?
    Fedora 39 Workstation
    How did you install Fedora? Did you use Live image or the Netinst method?
    Bootable pendrive
    Are there any errors shown when you examine the journal file? Try using journalctl --boot | grep error.
    Jan 24 21:41:18 fedora kernel: ACPI Error: Aborting method _SB.PCI0.AWMI.WMAA due to previous error (AE_NOT_FOUND) (20230628/psparse-529)
    Jan 24 21:41:18 fedora kernel: nvidia-wmi-ec-backlight: probe of 603E9613-EF25-4338-A3D0-C46177516DB7 failed with error -5
    Jan 24 21:41:35 fedora cupsd[1368]: REQUEST localhost - - “POST / HTTP/1.1” 200 151 Cancel-Subscription client-error-not-found
    What functional keys are non-operable? All of them? Or just some of them?
    All of them are operable, except for adjust brightness
6

This solution helped me
edit /etc/default/grub and include “acpi_backlight=native” at the end of your GRUB_CMDLINE_LINUX_DEFAULT stanza:

GRUB_CMDLINE_LINUX_DEFAULT="acpi_backlight=native"

Save your config and run “sudo grub2-mkconfig”. Reboot.

font: Lost screen backlight controls after upgrade to F37 - #3 by bouquetbouquet

Thanks, everyone

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Note that the /etc/default/grub file does not contain that line by default on fedora Workstation. Instead it is the GRUB_CMDLINE_LINUX line that should be edited.

When posting a suggested command such as “sudo grub2-mkconfig” it is much preferable to provide the full command as much as possible. sudo grub2-mkconfig -o /boot/grub2/grub.cfg which avoids ambiguity and user confusion especially with newer users.

1 Like
8

Acer Nitro AN515-47 has AMD+Nvidia graphics, so perhaps brightness is handled by AMD mechanisms and the presence of Nvidia is a source of confusion.

Please post the result from ls /sys/class/backlight/*.

Kernel parameters for screen brightness explains the ACPI mechanism and suggests acpi_backlight=vendor.