Unable to adjust brightness

[Mark Reeves]

I have an Intel NUC that's otherwise running Ubuntu 15.10 great! It's hooked up to a ViewSonic monitor via mini-DV / DVI.

The brightness controls are disabled on the monitor.

xbacklight does nothing. And I don't have the Brightness slider in Brightness & Lock.

I've been poking around, and have seen where to create a file in xorg.conf.d. The problem is, I have an empty /sys/class/backlight dir.

Per the following, I'm submitting a support ticket:

https://askubuntu.com/questions/577539/dell-chromebook-11-unable-to-set-backlight-and-sys-class-backlight-folder-is/578497#578497

I'd like to be able to increase the brightness on my screen.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: linux-image-4.2.0-19-generic 4.2.0-19.23
ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6
Uname: Linux 4.2.0-19-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: mark 2213 F.... pulseaudio
 /dev/snd/controlC0: mark 2213 F.... pulseaudio
CurrentDesktop: Unity
Date: Wed Dec 2 15:24:39 2015
HibernationDevice: RESUME=UUID=475f89b0-71dc-465f-997e-e88d611d948d
InstallationDate: Installed on 2015-11-24 (7 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.2.0-19-generic.efi.signed root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-4.2.0-19-generic N/A
 linux-backports-modules-4.2.0-19-generic N/A
 linux-firmware 1.149.2
SourcePackage: linux
UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/12/2015
dmi.bios.vendor: Intel Corporation
dmi.bios.version: RYBDWi35.86A.0350.2015.0812.1722
dmi.board.name: NUC5i5RYB
dmi.board.vendor: Intel Corporation
dmi.board.version: H40999-504
dmi.chassis.type: 3
dmi.modalias: dmi:bvnIntelCorporation:bvrRYBDWi35.86A.0350.2015.0812.1722:bd08/12/2015:svn:pn:pvr:rvnIntelCorporation:rnNUC5i5RYB:rvrH40999-504:cvn:ct3:cvr:

[Brad Figg (brad-figg)]

This change was made by a bot.

[Mark Reeves (mjr-w)]

Thanks, Christopher!

I successfully ran the BIOS update. I still do not see the Brightness slider control, or any files in /sys/class/backlight.

As requested, here are the results of the provided command:

RYBDWi35.86A.0352.2015.1130.1011
11/30/2015

Side note: Intel's F7 BIOS Flash Update was very straightforward, and not documented on the Ubuntu page provided: http://www.intel.com/support/motherboards/desktop/sb/CS-034499.htm

Mark

[Mark Reeves (mjr-w)]

Monitor controls also remain disabled following the BIOS update.

[penalvch (penalvch)]

Mark Reeves, could you please test the latest upstream kernel available from the very top line at the top of the page from http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D (the release names are irrelevant for testing, and please do not test the daily folder)? Install instructions are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds . This will allow additional upstream developers to examine the issue.

If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-X.Y-rcZ

Where X, and Y are the first two numbers of the kernel version, and Z is the release candidate number if it exists.

If the mainline kernel does not fix the issue, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-X.Y-rcZ

Please note, an error to install the kernel does not fit the criteria of kernel-bug-exists-upstream.

Once testing of the latest upstream kernel is complete, please mark this report's Status as Confirmed. Please let us know your results.

Thank you for your understanding.

[Mark Reeves (mjr-w)]

Thanks for the quick reply! I'm not technically disinclined to take these steps to further troubleshoot the issue, but am wary of undertaking steps this week that may result in being unable to "boot into the OS". Is this the only way to verify a fix? This is a primary development machine and a busy week here.

Mark

[penalvch (penalvch)]

Mark Reeves, it's not imperative you test this week, as this would be at your convenience.

However, when you do have time, you would have options:
1) Install Ubuntu to a different partition and then test this there.
2) Backup, or clone the primary install.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]