[Toshiba Portege Z935-ST4N03] Intel video: Display backlight cannot be changed

[JenniferHodgdon]

On my Toshiba Portege Z935-ST4N03 laptop, the display hotkeys and display brightness settings do not work at all.

Symptoms:
1. When I use Fn F6 or Fn F7, I get a pop-up window that shows a light bulb and a slider, and the slider goes obediently up and down as I press F6/7. However, the brightness of the screen does not change as the slider indicator changes.
2. If I go into the Power Manager and set the display brightness to dim after a few seconds has passed, it doesn't dim.

So it seems to me that the hotkeys are being recognized as a method to change the display brightness, but that the operating system is unable to change the hardware's actual screen brightness... I don't think it's a hotkey problem per se.

I read through https://wiki.ubuntu.com/Kernel/Debugging/Backlight and I think I have the problem defined as:

Backlight control does not work, but there are entries in /sys/class/backlight.

Although I do not seem to have the Brightness applet on my system (I am running XFCE, so maybe that is why), but the Power Manager's brightness control is definitely not working.

This is a recent install of Ubuntu, on a newly purchased laptop, so I have no idea whether it was working in previous versions of Ubuntu, kernels, etc. Sorry.

I used the "ubuntu-bug" utility to report this bug, so I am not sure what else you need... but I am starting by attaching the Xorg log, and will attach the lspci output and other information shortly. I am also going to follow the rest of the debugging steps on the Backlight debugging page and attach the output as separate comments on this report.

$ lsb_release -rd
Description: Ubuntu 13.04
Release: 13.04

$apt-cache policy xorg
xorg:
  Installed: 1:7.7+1ubuntu4
  Candidate: 1:7.7+1ubuntu4
  Version table:
 *** 1:7.7+1ubuntu4 0
        500 http://us.archive.ubuntu.com/ubuntu/ raring/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: xorg 1:7.7+1ubuntu4
ProcVersionSignature: Ubuntu 3.8.0-27.40-generic 3.8.13.4
Uname: Linux 3.8.0-27-generic x86_64
ApportVersion: 2.9.2-0ubuntu8.1
Architecture: amd64
Date: Mon Aug 19 14:01:34 2013
InstallationDate: Installed on 2013-06-17 (62 days ago)
InstallationMedia: Xubuntu 13.04 "Raring Ringtail" - Release amd64 (20130423.1)
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)

[JenniferHodgdon (yahgrp)]

lspci output:

$ lspci
00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
00:19.0 Ethernet controller: Intel Corporation 82579V Gigabit Network Connection (rev 04)
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
00:1c.2 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 3 (rev c4)
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM76 Express Chipset LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
01:00.0 System peripheral: Ricoh Co Ltd PCIe SDXC/MMC Host Controller (rev 07)
02:00.0 Network controller: Intel Corporation Centrino Wireless-N 2230 (rev c4)

$ lspci -vvnn
00:00.0 Host bridge [0600]: Intel Corporation 3rd Gen Core processor DRAM Controller [8086:0154] (rev 09)
 Subsystem: Toshiba America Info Systems Device [1179:0001]
 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ >SERR- <PERR- INTx-
 Latency: 0
 Capabilities: <access denied>

00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
 Subsystem: Toshiba America Info Systems Device [1179:0004]
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Interrupt: pin A routed to IRQ 44
 Region 0: Memory at e0000000 (64-bit, non-prefetchable) [size=4M]
 Region 2: Memory at d0000000 (64-bit, prefetchable) [size=256M]
 Region 4: I/O ports at 2000 [size=64]
 Expansion ROM at <unassigned> [disabled]
 Capabilities: <access denied>
 Kernel driver in use: i915

00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) (prog-if 30 [XHCI])
 Subsystem: Toshiba America Info Systems Device [1179:0001]
 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Interrupt: pin A routed to IRQ 40
 Region 0: Memory at e0620000 (64-bit, non-prefetchable) [size=64K]
 Capabilities: <access denied>
 Kernel driv...

[JenniferHodgdon (yahgrp)]

I am now following the steps on https://wiki.ubuntu.com/Kernel/Debugging/Backlight

The first step was to reboot with default Linux parameters. I had been using "acpi-backlight=vendor". When I took that out and rebooted, the symptoms changed: the hotkeys no longer make the slider on the pop-up brightness widget go up and down. And they still also don't change the screen brightness.

Anyway, I'll be attaching the files requested on that page for debugging.

1. ls /sys/class/backlight > backlight

[JenniferHodgdon (yahgrp)]

2. grep -r . /proc/acpi > acpi

[JenniferHodgdon (yahgrp)]

3. sudo acpidump -o acpidump.txt

[JenniferHodgdon (yahgrp)]

4. acpixtract acpidump.txt

This produces 4 files, which I'll attach... I guess you have to do each one as a separate comment.

[JenniferHodgdon (yahgrp)]

5. iasl -d DSDT.dat

[JenniferHodgdon (yahgrp)]

6. sudo fwts > fwts

Note: the fwts file has pretty much nothing in it. I'm assuming what's wanted here is results.log.

[JenniferHodgdon (yahgrp)]

7. sudo fwts method > fwts_method

Again, the fwts_method file has pretty much anything in it. You might want to update the instructions so that they say to clear out the results.log file and attach this instead of redirecting output to fwts/fwts_method for these two commands.

[JenniferHodgdon (yahgrp)]

8. dmesg | grep 'ACPI: Video' > video

[JenniferHodgdon (yahgrp)]

9. sudo dmidecode > dmidecode.log

[JenniferHodgdon (yahgrp)]

10. cat /proc/version > version

Linux version 3.8.0-27-generic (buildd@roseapple) (gcc version 4.7.3 (Ubuntu/Linaro 4.7.3-1ubuntu1) ) #40-Ubuntu SMP Tue Jul 9 00:17:05 UTC 2013

[JenniferHodgdon (yahgrp)]

11. Rebooted with acpi_backlight=vendor (which had been my usual boot mode; symptoms noted in orginal report).

12.
$ ls /sys/class/backlight > vendorbacklight

This reports:
intel_backlight
toshiba

13. As root:
ls -la /sys/class/backlight/intel_backlight/ > lslabacklight
(attached)

[JenniferHodgdon (yahgrp)]

14. As root, I tried

echo 8 > /sys/class/backlight/intel_backlight/brightness

Voila! Finally it is doing something. This made the screen almost too dim to see.

echo 1000 > /sys/class/backlight/intel_backlight/brightness

This made the display usable again.

The next step involves rebooting again... I'll be back shortly.

[JenniferHodgdon (yahgrp)]

I have just rebooted with kernel parameter video.use_bios_initial_backlight=0 and it does not behave differently from the default boot parameters.

So... I think I've finished following all of the steps in https://wiki.ubuntu.com/Kernel/Debugging/Backlight

- I don't have a Thinkpad.
- I checked and I am not using the thinkpad_acpi kernel module.

Let me know if there is anything else I can do to debug.

In particular, I would like to test a brightness applet as mentioned on that page but I cannot located it. Any idea what package it would be in or where I would find it?

[JenniferHodgdon (yahgrp)]

Additional information:

While debugging another issue on this same laptop (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1214180) I installed and booted into the latest mainline kernel (labeled v3.11-rc6-saucy, following instructions on https://wiki.ubuntu.com/KernelMainlineBuilds

This kernel did **not** fix my brightness problems. Then again, it is probably not a kernel bug so maybe this information is not helpful, but I thought I'd post it just in case.

[penalvch (penalvch)]

JenniferHodgdon, this bug was reported a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue? If so, could you please test for this with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux REPLACE-WITH-BUG-NUMBER

Please note, given that the information from the prior release is already available, doing this on a release prior to the development one would not be helpful.

If reproducible, could you also please test the latest upstream kernel available (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-v3.13-rc7

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[JenniferHodgdon (yahgrp)]

Unfortunately, due to bug #1257817 I am unable to test Ubuntu ISO images, as of 30 days ago anyway, because I cannot boot off a USB stick with an Ubuntu ISO image on it.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1257817

So, please let me know if there is something else you would like me to test, or some other method you would like me to use for testing.

[penalvch (penalvch)]

JenniferHodgdon, thank you for your comment. Let us put on hold further testing towards live environments for now, until the boot issue you noted is resolved.

[JenniferHodgdon (yahgrp)]

I was testing some other issues today and tested this one as well.

I am currrently running Ubuntu 13.10 Saucy with kernel 3.11.0-15-generic

I can confirm that this problem still exists:
- The fn F6/F7 hot keys for brightness show the light bulb and slider but have no effect on screen brightness
- As root, I can echo numbers into /sys/class/backlight/intel_backlight/brightness to change the screen brightness up and down

So it appears the disconnect is between the hotkeys and that file. When I use the hotkeys, that file does not change. I'm assuming it should be changing?

[Carlos Reig (unstatu)]

Hi JenniferHodgon,

I had the same bug as you and I have just resolved it following these steps:

Creating the file /usr/share/X11/xorg.conf.d/80-backlight.conf and filling it with:

Section "Device"
    Identifier "Intel Graphics"
    Driver "intel"
    Option "AccelMethod" "sna"
    Option "Backlight" "intel_backlight" # use your backlight that works here
    BusID "PCI:0:2:0"
EndSection

Bassically, I have followed the steps described in the section "For the Intel HD Graphic Controllers" from https://wiki.ubuntu.com/Kernel/Debugging/Backlight (this link was reported by you, thanks ;) )

Good luck,
Carlos
Cheers

[JenniferHodgdon (yahgrp)]

Thanks Carlos Reig!

Either I didn't see that last time I visited the Debugging page, or it has been added recently.

Anyway, the solution in comment #25 worked for me.

So... it looks like something like this needs to get into Ubuntu by default for this laptop. I have no idea how that would be accomplished, but that is indeed the solution.

[Vangelis Tasoulas (cyberang3l)]

Solution in comment #25 solves the problem for me in a Toshiba Portege Z830.

Thanks!

[penalvch (penalvch)]

Vangelis Tasoulas, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Alan Pater (alan-pater)]

Symptom sometimes occurs on a R700 Toshiba when returning from sleep mode. Restarting the system restores this functionality.

I am running Ubuntu 14.04 64 bit.
~$ uname -psrv
Linux 3.13.0-29-generic #53-Ubuntu SMP Wed Jun 4 21:00:20 UTC 2014 x86_64

I could also adjust the brightness from the terminal:

~$ cat /sys/class/backlight/intel_backlight/brightness
1030

~$ grep . /sys/class/backlight/intel_backlight/*
/sys/class/backlight/intel_backlight/actual_brightness:1030
/sys/class/backlight/intel_backlight/bl_power:0
/sys/class/backlight/intel_backlight/brightness:1030
/sys/class/backlight/intel_backlight/max_brightness:4539

So, to temporarily increase the screen brightness:

~$ echo 3030 | sudo tee /sys/class/backlight/intel_backlight/brightness
3030

[penalvch (penalvch)]

Alan Pater, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Zwopper (zwopper)]

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1214148/comments/25
Comment #25 works for my R930 as well!
Thank you Carlos!