Brightness change is negligible or fixed. Archlinux. HP Victus

[easyapple324]

There is a problem with HP Victus brightness level in arch linux, On startup its quite dim. On searching more that it seems to be the same case in any distros on victus laptops. By default the directory in /sys/class/backlight is amdgpu_bl1 and brightness is quite low and change slightly and is reversed 0 (highest) 255 (lowest(By manually writing to file or using `light`)

When kernel parameters acpi_backlight=video is passed, the directory is acpi_video0 and brightness is max, the values can range from 0-49 but has no affect, can't decrease brightness.

Bumping: https://h30434.www3.hp.com/t5/Notebook-Video-Display-and-Touch/Lack-of-brightness-control-in-linux/m.... Exact symptoms, exact problems, I've tried all kernel params, uninstalling nvidia drivers(current state). I don't think it's Xorg problem. It's a kernel related issue, persists on plasma(wayland) and dwm(xorg).

[Raj_05]

Hi @easyapple324,

Welcome to HP Support Community.

Thank you for posting your query, I will be glad to help you.

It sounds like you're facing a common issue with AMD GPUs and backlight control on Linux, especially with newer laptops like the HP Victus series. Here’s a step-by-step approach to potentially resolve this issue.

Check Available Kernel Modules

First, ensure that the necessary kernel modules are loaded. For AMD GPUs, amdgpu is typically used. Check if it's loaded using:

lsmod | grep amdgpu

If it's not loaded, you can load it manually (though it should load automatically on boot if required).

Modify Grub Configuration

To attempt to regain control over backlight brightness, you can try modifying the GRUB configuration:

Edit the Grub configuration file. For example:

sudo nano /etc/default/grub

Find the line starting with GRUB_CMDLINE_LINUX_DEFAULT and append acpi_backlight=vendor amdgpu.backlight=0 to the existing parameters. It should look something like:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor amdgpu.backlight=0"

Save the file and exit the editor.

Update Grub:

sudo update-grub

 

Restart Your System

After updating Grub, restart your laptop to apply the changes.

Test Brightness Control

Once you're logged back in, check if you can control the brightness using your keyboard shortcuts or by writing directly to the brightness file in /sys/class/backlight.

Alternative: Install and Use light

If the above steps don't work, you can try using light, a lightweight program to control brightness:

Install light:

sudo apt-get install light

Set the brightness to a desired level (e.g., 50% brightness):

light -S 50

Adjust the percentage as needed.

By following these steps, you should be able to regain control over the brightness levels on your HP Victus laptop running Arch Linux or any other Linux distribution.

I hope this helps.

Take care and have a good day.

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!

Alden4

HP Support

[easyapple324]

Thanks for you response, I tried it, but now there doesn't seem to be a backlight file in /sys/class/backlight now (btw, in case you haven't noticed, I've uninstalled all nvidia drivers so I can get it working with amd at least)

Light also says `No backlight controlled was found, so we could not decide an automatic target` It also says I can light available lights using -L which gives caps lock, poweron etc buttons

Also what exactly does `amdgpu.backlight=0` do? And lsmod does show amdgpu already loaded

[Raj_05]

Hi @easyapple324,

Thank you for your response, 

I'm sending a private message to assist you with the next action.

Please check your Private message icon on the upper right corner of your HP Community profile Next, to your profile Name, you should see a little blue envelope, please click on it or simply click on this link.

I hope this helps! Keep me posted.

Alden4

HP Support 

[Rich1015]

I'm having the exact same issue with my HP Victus Laptop on Arcolinux (Arch based). Have you found a fix or solution to this?