Comment 0 for bug 1905591

Revision history for this message
Kamal Mostafa (kamalmostafa) wrote : no brightness control after update from 450 to 455

On my Lenovo X1 Extreme with GPU: NVIDIA Corporation GP107M [GeForce GTX 1050 Ti Mobile]

Updating to nvidia-driver-455 results in loss of brightness control. On boot, the laptop display brightness is somewhat less than fully bright and cannot be changed. The brightness up/down keys do pop up the gnome gui brightness widget, and /sys/class/backlight/nvidia_0/* values do change, but the actual display's brightness does not.

Problem occurs with either version of nvidia-driver-455 (the archive or the ~graphics-drivers/PPA).
 Normal functionality returns if I downgrade to any version of nvidia-driver-450.

Note also that manually applying this has no effect on the problem:
https://github.com/hugh712/nvidia-graphics-drivers/commit/bccad5ee6444dd8c5c47ba19ea0232106a1086f5

Distributor ID: Ubuntu
Description: Ubuntu 18.04.5 LTS
Release: 18.04
Codename: bionic

kernel: 5.4.0-54-generic #60~18.04.1-Ubuntu SMP Fri Nov 6 17:25:16 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

nvidia-driver-455: 455.38-0ubuntu0.18.04.1