On 4.13 kernels I cannot change brightness of my display. Other users of the same laptop model also have the issue. Using kernel 4.10 the problem doesn't happen and brightness can be changed using hardware buttons(fn+f5, fn+f6). On 4.13 I cannot find any settings that would allow me to change brightness.
On 4.13 linux always starts with really dimmed screen which makes the computer hard to use in any kind of daylight, even indoors.
lsb_release -rd:
Description: Ubuntu 16.04.3 LTS
Release: 16.04
uname -a:
Linux redacted-ThinkPad-P51 4.13.0-32-generic #35~16.04.1-Ubuntu SMP Thu Jan 25 10:13:43 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
(also happens in any earlier version of 4.13, I need to revert up to 4.10 in order for it to work)
Hardware:
Lenovo ThinkPad P51 15.6"
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.13.0-32-generic 4.13.0-32.35~16.04.1
ProcVersionSignature: Ubuntu 4.13.0-32.35~16.04.1-generic 4.13.13
Uname: Linux 4.13.0-32-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
CurrentDesktop: Unity
Date: Tue Feb 20 09:00:09 2018
InstallationDate: Installed on 2017-10-03 (139 days ago)
InstallationMedia: Ubuntu 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
SourcePackage: linux-hwe
UpgradeStatus: No upgrade log present (probably fresh install)
---
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: lchr 2877 F.... pulseaudio
/dev/snd/controlC1: lchr 2877 F.... pulseaudio
CurrentDesktop: ubuntu:GNOME
DistroRelease: Ubuntu 18.04
InstallationDate: Installed on 2018-04-04 (41 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20180105.1)
MachineType: LENOVO 20HJS1NW00
NonfreeKernelModules: nvidia_modeset nvidia
Package: linux (not installed)
ProcEnviron:
TERM=xterm-256color
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=pl_PL.UTF-8
SHELL=/bin/bash
ProcFB: 0 EFI VGA
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-20-generic root=UUID=3afbbc52-6d66-4597-a1f2-6254d9f44643 ro quiet splash vt.handoff=1
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
RelatedPackageVersions:
linux-restricted-modules-4.15.0-20-generic N/A
linux-backports-modules-4.15.0-20-generic N/A
linux-firmware 1.173
Tags: bionic
Uname: Linux 4.15.0-20-generic x86_64
UpgradeStatus: Upgraded to bionic on 2018-05-11 (5 days ago)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 07/24/2017
dmi.bios.vendor: LENOVO
dmi.bios.version: N1UET37W (1.11 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20HJS1NW00
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN1UET37W(1.11):bd07/24/2017:svnLENOVO:pn20HJS1NW00:pvrThinkPadP51:rvnLENOVO:rn20HJS1NW00:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad P51
dmi.product.name: 20HJS1NW00
dmi.product.version: ThinkPad P51
dmi.sys.vendor: LENOVO
This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1750513
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.