Arch Linux

toxa

Member

Registered: 2023-07-23

Posts: 3

Black screen until screen brightness is changed on a laptop

My laptop is Asus Zenbook 15 oled (UM3504DA), using latest stable kernel 6.6.7

when I start Hyprland from TTY or SDDM the screen turns off.
I can blindly start alacritty and type "brightnessctl s 60" which fixes it.
If I just type "brightnessctl" while the screen is off, it outputs previously used brightness value != 0.
If I press Super+M (exit hyprland by default) screen turns off again.

same with KDE Plasma (wayland), screen turns on when I press fn+f3 (change brightness)
KDE Plasma (X11) works fine.

I have SDDM enabled, it works fine unless I exit hyprland.

toxa

Member

Registered: 2023-07-23

Posts: 3

Re: Black screen until screen brightness is changed on a laptop

Issue is not present on linux-lts, but I need 6.6.7 because it has sound quirk for my device

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,900

Re: Black screen until screen brightness is changed on a laptop

If the kernel changelog is anything to go by, this is likely fixed in 6.6.8

commit c7f6e836e675683e704a40e68eded505bdc30428
Author: Mario Limonciello <mario.limonciello@amd.com>
Date:   Wed Dec 6 12:08:26 2023 -0600

    drm/amd/display: Restore guard against default backlight value < 1 nit
   
    commit b96ab339ee50470d13a1faa6ad94d2218a7cd49f upstream.
   
    Mark reports that brightness is not restored after Xorg dpms screen blank.
   
    This behavior was introduced by commit d9e865826c20 ("drm/amd/display:
    Simplify brightness initialization") which dropped the cached backlight
    value in display code, but also removed code for when the default value
    read back was less than 1 nit.
   
    Restore this code so that the backlight brightness is restored to the
    correct default value in this circumstance.
   
    Reported-by: Mark Herbert <mark.herbert42@gmail.com>
    Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3031
    Cc: stable@vger.kernel.org
    Cc: Camille Cho <camille.cho@amd.com>
    Cc: Krunoslav Kovac <krunoslav.kovac@amd.com>
    Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
    Fixes: d9e865826c20 ("drm/amd/display: Simplify brightness initialization")
    Acked-by: Alex Deucher <alexander.deucher@amd.com>
    Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>