intel – Dell Venue 11 Pro 7130 vPro volume buttons and brightness

Tablet: Dell Venue 11 Pro 7130 vPro
Kernel: Linux version 5.11.0-34-generic
RAM: 3840 MB
ROM: Windows 8.1, Ubuntu 20.04.3, Android 7

My tablet is a monitor, with the ability to unfasten the keyboard with a built-in touchpad.

  1. After upgrading to Ubuntu version 20.04.3, I got a black screen and I reinstalled Ubuntu using the Grub: function “Ubuntu (source graphics)” because the normal “Ubuntu” mode did not work when installing from a USB media.
    After installation, I got into the Grub menu, went to the additional startup functions and started Ubuntu in (recovery mode).
  2. I updated the software, entered the account details and the console password. Edited Grub: sudo gedit /etc/default/grub,added a line: nomodeset, updated: sudo update-grub. Rebooted the device in normal mode.
  3. At first glance, everything seemed to work fine, except for the lack of the ability to change the screen resolutions, it was stuck at the value of 1920x1080, there are no other parameters.
  4. When I unfastened the keyboard, the volume buttons on the tablet stopped working, and I added the module intel_vbtn to the blacklist. Now the volume control buttons on the tablet work correctly.
button/volumeup VOLUP 00000080 00000000 K
button/volumedown VOLDN 00000080 00000000 K
  1. But now the screen brightness does not work, there are no brightness adjustment sliders in the tray and it does not work even on the keyboard.
video/brightnessup BRTUP 00000086 00000000 K
video/brightnessdown BRTDN 00000087 00000000 K


What would be more practical to give up, the volume buttons or the brightness ?
Perhaps, there are other options, but in the “nomodeset” mode, I’m not sure.

cat /sys/class/backlight/acpi_video0/max_brightness
cat: /sys/class/backlight/acpi_video0/max_brightness: There is no such file or directory