Brightness Adjustment

Discussion in 'Linux Compatibility and Software' started by TriBeard, Jun 9, 2017.

  1. TriBeard

    TriBeard Notebook Consultant

    Reputations:
    21
    Messages:
    188
    Likes Received:
    16
    Trophy Points:
    31
    I have a dell 7710, and I just installed Korora 25 on it. This problem was also present under generic Fedora, but I prefer Cinnamon to Gnome.

    The issue is that the brightness fn keys don't work. It appears as though they're changing the value in the wrong file. In my /sys/class/backlight I have a folder for amd_gpu and intel_backlight. I can see the fn keys adjusting the value in the amd_gpu/brightness file, but this does nothing. If I change the values manually in the intel_backlight/brightness file the brightness of the screen changes. Is there any way to remap this?
     
  2. Primes

    Primes Notebook Deity

    Reputations:
    676
    Messages:
    1,596
    Likes Received:
    533
    Trophy Points:
    131
    Just a thought, have you tried setting acpi_backlight=vendor on the boot command line?
     
    krisguy and steberg like this.
  3. TriBeard

    TriBeard Notebook Consultant

    Reputations:
    21
    Messages:
    188
    Likes Received:
    16
    Trophy Points:
    31
    I tried that to no avail. I also have tried to use the dconf-editor to edit "backlight-helper-force" and "backlight-helper-preference-order" but it doesn't seem to make a difference what they're set as, the brightness still doesn't change.
     
  4. Vasudev

    Vasudev Notebook Prophet

    Reputations:
    3,024
    Messages:
    6,132
    Likes Received:
    3,927
    Trophy Points:
    431
    Does Korora 25 come with kernel version 4.8.x, if its lower say 4.4 I'd advise you to upgrade to 4.8 to get better support for skylake models and battery life improvements.
     
  5. TriBeard

    TriBeard Notebook Consultant

    Reputations:
    21
    Messages:
    188
    Likes Received:
    16
    Trophy Points:
    31
    I just checked, and the live usb is on version 4.8. I'm installing again (I had switched to a different distro to test) and I will see if updating the kernel makes any difference. Brightness adjustment works on linux Mint 18.2, Antergos (Arch Linux), and Ubuntu 17.04 as well.
     
  6. Vasudev

    Vasudev Notebook Prophet

    Reputations:
    3,024
    Messages:
    6,132
    Likes Received:
    3,927
    Trophy Points:
    431
    Try Ubuntu/Xubuntu LTS version 16.04.2, it comes with 4.8 kernel. Sometimes, brightness on LiveCD works and after installing the brightness doesn't work. Though, its a rare case.
     
  7. TriBeard

    TriBeard Notebook Consultant

    Reputations:
    21
    Messages:
    188
    Likes Received:
    16
    Trophy Points:
    31
    Oddly enough, it didn't work with 17.04 when installed actually. I thought it would because it worked with mint, but it was a no go. That said, I installed the Fedora 26 beta, and it's working just fine there once it's updated to current. I really prefer fedora to ubuntu anyway, so I think I'll just stay here, at least for now. Thanks for the suggestions and the help.
     
  8. Vasudev

    Vasudev Notebook Prophet

    Reputations:
    3,024
    Messages:
    6,132
    Likes Received:
    3,927
    Trophy Points:
    431
    Sorry to hear that. Now, I sound like a company representative, Haha. If you want to try Ubuntu 16, make sure the NV driver you choose must be v375 or greater.
     
  9. DeadLink404

    DeadLink404 Newbie

    Reputations:
    0
    Messages:
    6
    Likes Received:
    2
    Trophy Points:
    5
    Have you tried putting the line
    Option "backlight" "intel_backlight"
    in the xorg conf section for the intel gpu?
     
  10. alarawany

    alarawany Newbie

    Reputations:
    0
    Messages:
    1
    Likes Received:
    0
    Trophy Points:
    5
    option backlight...
     
Loading...

Share This Page