[Dell Inspiron 2350] could not control brightness

[Taihsiang Ho]

Dell Inspiron 2350 (CID 201305-13669) with Ubuntu 14.04.1
Linux 201305-13669 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
VGA compatible controller [0300]: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06)

Steps to reproduce this bug:
1. install Ubuntu 14.04.1
2. after installing, boot into desktop
3. dash --> brightness

Expected result:
There is an brightness slider on the brightness panel

Actual result:
There is no such slider.

More information:

/sys/class/backlight/ shows nothing

ubuntu@201305-13669:~$ ls /sys/class/backlight/
ubuntu@201305-13669:~$

---------------------------------------------------------------
ApportVersion: 2.14.1-0ubuntu3.2
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: ubuntu 1476 F.... pulseaudio
 /dev/snd/controlC1: ubuntu 1476 F.... pulseaudio
CurrentDesktop: Unity
CurrentDmesg:
 [ 15.148179] thinkpad_ec: no ThinkPad embedded controller!
 [ 17.013792] init: plymouth-upstart-bridge main process ended, respawning
 [ 17.021574] init: plymouth-upstart-bridge main process ended, respawning
 [ 17.969005] r8169 0000:03:00.0 eth0: link up
 [ 17.969013] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
DistroRelease: Ubuntu 14.04
HibernationDevice: RESUME=UUID=a6237ffe-4fa9-4ab7-9253-55430263f86f
InstallationDate: Installed on 2014-12-08 (2 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
MachineType: Dell Inc. Inspiron 2350
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-32-generic root=UUID=fe7cefb8-002c-4091-9a6e-6cab455727b5 ro rootdelay=60 quiet splash initcall_debug vt.handoff=7
ProcVersionSignature: Ubuntu 3.13.0-32.57-generic 3.13.11.4
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-32-generic N/A
 linux-backports-modules-3.13.0-32-generic N/A
 linux-firmware 1.127.5
Tags: trusty
Uname: Linux 3.13.0-32-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 09/02/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A02
dmi.board.name: 08NG84
dmi.board.vendor: Dell Inc.
dmi.board.version: X01
dmi.chassis.type: 13
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 00
dmi.modalias: dmi:bvnDellInc.:bvrA02:bd09/02/2013:svnDellInc.:pnInspiron2350:pvr00:rvnDellInc.:rn08NG84:rvrX01:cvnDellInc.:ct13:cvr00:
dmi.product.name: Inspiron 2350
dmi.product.version: 00
dmi.sys.vendor: Dell Inc.

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

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[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

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[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

apport information

[Taihsiang Ho (tai271828)]

The attachment no-brightness-bar-before-S3.png shows how the brightness control panel looks like.

[Taihsiang Ho (tai271828)]

may related to LP: #1218547

[Brad Figg (brad-figg)]

This change was made by a bot.

[Taihsiang Ho (tai271828)]

This bug may be related to LP: #1218547

[Taihsiang Ho (tai271828)]

There are buttons on the monitor of Dell Inspiron 2350 and they could control the brightness successfully.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.18 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.18-vivid/

[Brad Figg (brad-figg)]

This change was made by a bot.

[Taihsiang Ho (tai271828)]

tested CID 201305-13669 with mainline kernel

ubuntu@201305-13669:~$ uname -a
Linux 201305-13669 3.18.0-031800-generic #201412071935 SMP Mon Dec 8 00:36:34 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
ubuntu@201305-13669:~$ ls /sys/class/backlight/
ubuntu@201305-13669:~$

the issue is still there.