Hi @rrameshbabu,
Sorry if I am still bothering… Any news?
@rrameshbabu
Hey sorry, are u still there? I tried again every possible setting, parameter and more, also tried again other distros, kernels and live boot too..
Hi @r3aloblivion,
Tried this too.. I can see nvidia_0 under /sys/class/backlight every time and in the file
brightnessandactual_brightness
In theory, you should not see nvidia_0 if you followed my second set of instructions from my previous post, so I presume you did not successfully unload the NVIDIA driver for the experiment.
modprobe -r nvidia_drm nvidia_modeset
modprobe -r asus_nb_wmi
modprobe asus_nb_wmi
After modprobe -r nvidia_drm nvidia_modeset, make sure lsmod | grep -i nvidia returns blank output. If these commands return any errors, be sure to share. Thanks in advance.
Hi @rrameshbabu ,
If I try to unload only the specific components listed by you I get modprobe: FATAL: Module nvidia_drm is in use, but somehow I managed to unload them by unloading also the other components that were using them; the problem is that after I got black screen so couldn’t check anything. Idk if it can be useful but as I know my laptop has the iGPU hardware-locked or maybe not available at all.. If you search the model of my laptop no one has been able to fix the thing on linux.. See this link https://unix.stackexchange.com/questions/761922/pop-os-brightness-stuck-at-maximum. Thank you a lot for your time and your effort into this
@rrameshbabu Hi again after some months.. sorry if I am still bothering.. Nothing changed at all, brightness still not working :(
Hi @r3aloblivion,
I apologize for the lack of follow up. Would you mind trying the following kernel parameter and let me know what the behavior is on this laptop?
acpi_backlight=nvidia_wmi_ec
Thanks.
Rahul Rameshbabu
@rrameshbabu
I tried acpi_backlight=nvidia_wmi_ec and in sys/class/backlight the directory nvidia_0 disappeared and there was no other directory, so 0 interfaces to change the brightness.
But I have a really important update.. I tried an old version of ubuntu, the 20.02LTS, with nvidia driver 440.64 and guess what.. the brightness control was working perfectly. Then I update the driver to 470.256.02 and again brightness wasn’t working anymore. Tried either to maintain the same kernel version or to update it but the result was the same. At that point I could assure that the problem was the nvidia driver. I tried to look for some diffs between the two driver versions in the visible parameters/settings of the modules and the only noticeable diff was the missing param NVreg_EnableBacklightHandler:int but I don’t know if this has anything to do with the issue.
I’m uploading 4 files to better understand the settings of both the driver versions.
The 2 files “nvidia440.txt” and “nvidia470.txt” contains the following commands (based on the version wrote in the file name):
- $ cat /proc/driver/nvidia/params
- $ lsmod
- $ uname -a
- $ sudo lshw -c video
- $ sudo journalctl -b | grep -i “nvidia”
- $ modinfo nvidia
And the two bug reports for both versions.
Thanks a lot for all the time and the effort that you are putting to help me! I hope that with these new updates we can finally fix the issue! :). If you need anything else feel free to ask and I’ll provide you everything!
nvidia-bug-report470.log (1.2 MB)
nvidia-bug-report440.log (760.6 KB)
nvidia470.txt (41.9 KB)
nvidia440.txt (39.7 KB)
Hi @r3aloblivion ,
Still going through the logs. Can you share the output of ls /sys/class/backlight for the working case vs non-working case?
Yeah, without kernel params it’s the same in both cases
$ ls /sys/class/backlight
nvidia_0
With acpi_backlight=nvidia_wmi_ec on Arch Linux the directory is empty but on Ubuntu there is still nvidia_0. Anyway in both I can’t control brightness on driver 470
@rrameshbabu Hi sorry, do you have some news?
@rrameshbabu Hi I’m still writing.. sry.. Is there any hope to get a fix? :(