Arch Linux'da ekran parlaklığı uzun süredir ayarlanamıyor

[arch@veysel ~]$ inxi -SGMxx
System:
 Host: veysel Kernel: 6.5.4-arch2-1 arch: x86_64 bits: 64 compiler: gcc.
 v: 13.2.1 Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.36 wm: xfwm dm: 1: LightDM.
 2: SDDM note: stopped Distro: Arch Linux.
Machine:
 Type: Laptop System: Acer product: Extensa 5635Z v: N/A
 serial: <superuser required> Chassis: type: 10 serial: <superuser required>
 Mobo: Acer model: BA50-MV serial: <superuser required> BIOS: Phoenix.
 v: 0.3310 date: 11/20/2009
Graphics:
 Device-1: Intel Mobile 4 Series Integrated Graphics.
 vendor: Acer Incorporated ALI driver: i915 v: kernel arch: Gen-5 ports:
 active: LVDS-1 empty: DP-1, DP-2, HDMI-A-1, VGA-1 bus-ID: 00:02.0
 chip-ID: 8086:2a42
 Device-2: SuYin Video WebCam driver: uvcvideo type: USB rev: 2.0
 speed: 480 Mb/s lanes: 1 bus-ID: 8-8:3 chip-ID: 064e:a103
 Display: x11 server: X.Org v: 21.1.8 compositor: xfwm v: 4.18.0 driver: X:
 loaded: intel dri: crocus gpu: i915 display-ID: :0.0 screens: 1
 Screen-1: 0 s-res: 1366x768 s-dpi: 96.
 Monitor-1: LVDS-1 mapped: LVDS1 model: Chi Mei Opto 0x1680 res: 1366x768.
 dpi: 99 diag: 398mm (15.7")
 API: OpenGL v: 2.1 Mesa 23.1.8-arch1.1 renderer: Mesa Mobile Intel GM45.
 Express (CTG) direct-render: Yes.
[arch@veysel ~]$ ls /sys/class/backlight/
acpi_video0.
[arch@veysel ~]$

ls /sys/class/backlight/
cat /etc/X11/xorg.conf.d/20-intel.conf

acpi_video0

acpi_video0
Section "Device"
    Identifier  "Intel Graphics"
    Driver      "intel"
    Option      "Backlight"  "intel_backlight"
EndSection