Every time booting to the OS, brightness is set to 100%. Could you please clarify what information you need to help support with the issue?
I attach basic information below
Device in question - Lenovo legion-5-pro-16ach6h
nvidia-smi
NVIDIA-SMI 530.41.03 Driver Version: 530.41.03 CUDA Version: 12.1
NVIDIA GeForce RTX 3070 L… Off| 00000000:01:00.0 On | N/A
cat /etc/os-release
NAME=EndeavourOS
PRETTY_NAME=EndeavourOS
ID=endeavouros
ID_LIKE=arch
BUILD_ID=2023.03.06
ANSI_COLOR=“38;2;23;147;209”
HOME_URL=‘endeavouros.com’
…
…
LOGO=endeavouros
uname -a
Linux 6.2.11-arch1-1 #1 SMP PREEMPT_DYNAMIC Thu, 13 Apr 2023 16:59:24 +0000 x86_64 GNU/Linux
after reset, these values are set:
cat /sys/class/backlight/nvidia_0/actual_brightness
10
cat /sys/class/backlight/nvidia_0/brightness
10
The brightness is saved/restored by systemd, with the systemd-backlight units.
what does that mean? Is that not part of Nvidia issue then? Can you point me where I can get more answers?
~ systemctl list-units |grep backlight
sys-devices-pci0000:00-0000:00:01.1-0000:01:00.0-backlight-nvidia_0.device loaded active plugged /sys/devices/pci0000:00/0000:00:01.1/0000:01:00.0/backlight/nvidia_0
systemd-backlight@backlight:nvidia_0.service loaded active exited Load/Save Screen Backlight Brightness of backlight:nvidia_0
system-systemd\x2dbacklight.slice loaded active active Slice /system/systemd-backlight
~ systemctl status sys-devices-pci0000:00-0000:00:01.1-0000:01:00.0-backlight-nvidia_0.device
● sys-devices-pci0000:00-0000:00:01.1-0000:01:00.0-backlight-nvidia_0.device - /sys/devices/pci0000:00/0000:00:01.1/0000:01:00.0/backlight/nvidia_0
Loaded: loaded
Active: active (plugged) since Mon 2023-04-24 22:24:21 BST; 4min 28s ago
Device: /sys/devices/pci0000:00/0000:00:01.1/0000:01:00.0/backlight/nvidia_0
~ systemctl status systemd-backlight@backlight:nvidia_0.service
● systemd-backlight@backlight:nvidia_0.service - Load/Save Screen Backlight Brightness of backlight:nvidia_0
Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
Active: active (exited) since Mon 2023-04-24 22:24:21 BST; 3min 26s ago
Docs: man:systemd-backlight@.service(8)
Process: 736 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:nvidia_0 (code=exited, status=0/SUCCESS)
Main PID: 736 (code=exited, status=0/SUCCESS)
CPU: 6ms
Apr 24 22:24:21 systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:nvidia_0…
Apr 24 22:24:21 systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:nvidia_0.
~ systemctl status system-systemd\x2dbacklight.slice
○ system-systemdx2dbacklight.slice - Slice /system/systemdx2dbacklight
Loaded: loaded
Active: inactive (dead)
Looks normal. Please check in which ways the values of cat /sys/class/backlight/nvidia_0/brightness change when you change the brightness manually.
after reboot its set to
~ cat /sys/class/backlight/nvidia_0/brightness
10
Below is the slider with the 10 value, although it appears that 10 is equal to 100%.
after moving the brightness slider to the middle, screen gets darker and the output is as follows:
~ cat /sys/class/backlight/nvidia_0/brightness
52
after moving the brightness slider to the right completely, the output is as follows (which is the same screen brightness as after reboot):
~ cat /sys/class/backlight/nvidia_0/brightness
100
the above is exactly as described here: Backlight problem · Issue #409 · NVIDIA/open-gpu-kernel-modules · GitHub
There is another value, which might be related? This appears to be 100 all the time, whenever I change the sliders:
~ ls -la /var/lib/systemd/backlight
total 12
drwxr-xr-x 2 root root 4096 Mar 14 21:46 .
drwxr-xr-x 10 root root 4096 Mar 14 21:45 …
-rw-r–r-- 1 root root 4 Mar 14 22:06 pci-0000:01:00.0:backlight:acpi_video0
~ cat /var/lib/systemd/backlight/pci-0000:01:00.0:backlight:acpi_video0
100