Ubuntu – Ubuntu 20.04 Intel HD 615: No Brightness control or no Boot / Stuck on Boot Screen

20.04brightnessintel graphics

I just did a fresh install of Ubuntu 20.04 on my dell xps9365 with intel HD615 graphics & 4k display

1. First boot:

In the Settings > About I can see that it is using the Mesa Intel HD Graphics 615 (KBL GT2)
At this point i also have a slider to adjust my brightness.

2. First REboot:

At the first reboot its not working anymore.
It keeps hanging at splash screen. So i did some searching and added nomodeset to my grub file before booting.
It Boots up! But now i don't have my brightness slider
and i see it is using the llvmpipe drivers instead of the Mesa Intel HD Graphics 615 (KBL GT2).

I tried to change GRUB_CMDLINE_LINUX_DEFAULT to different variants:

quiet splash nomodeset video.use_native_backlight=1
quiet splash nomodeset acpi_backlight=video
quiet splash nomodeset acpi_backlight=vendor
quiet splash nomodeset acpi_backlight=native

nomodeset video.use_native_backlight=1
nomodeset acpi_backlight=video
nomodeset acpi_backlight=vendor
nomodeset acpi_backlight=native

But all give the same result: llvmpipe drivers and no brightness control.

When i was reading trough some post this is what i learned also: nomodeset disabled the drivers during boot, so you don't have a fancy splash screen. Once the machine is booted it would load the proper drivers. But for some reason it doesn't seem to be working for me.

Can someone please help?

Best Answer

I found the solution myself!

in the file : /etc/default/grub

change this line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT=""

and then

sudo update-grub