Public bug reported: The screen brightness cannot be changed. It is always at maximum. Strangely enough, it happened once or twice (seemingly randomly) that I was able to change it, but after a reboot the brightness was again stuck in max.
My machine is a Lenovo T14s ThinkPad with AMD Ryzen 5 PRO 4650U with Radeon Graphics. I installed the drivers I found in the AMD site ('amdgpu-pro-18.40-697810-ubuntu-18.04' and 'amdgpu-pro-20.40-1147287-ubuntu-18.04'), but the issue remains (although it fixed the issue of not recognizing external monitor). I tried Ubuntu 20.04, but I get the same behavior. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: linux-image-5.4.0-52-generic 5.4.0-52.57~18.04.1 ProcVersionSignature: Ubuntu 5.4.0-52.57~18.04.1-generic 5.4.65 Uname: Linux 5.4.0-52-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.18 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Thu Oct 29 11:35:16 2020 InstallationDate: Installed on 2020-10-22 (6 days ago) InstallationMedia: Ubuntu 18.04.5 LTS "Bionic Beaver" - Release amd64 (20200806.1) SourcePackage: linux-signed-hwe-5.4 UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: linux-signed-hwe-5.4 (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug bionic -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1902035 Title: Screen brightness cannot be changed in Lenovo T14s with AMD Ryzen 5 PRO 4650U with Radeon Graphics To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe-5.4/+bug/1902035/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs