[HP Compaq nx6310] Function buttons for brightness stopped working

[Marcus Pollice]

In 14.04 using kernel 3.13 the special function buttons of this HP Compaq nx6310 laptop used to work correctly. I could increase or decrease brightness, invoke the battery settings (mostly useless but it worked), switch to an external display or enter sleep mode. The key functions are invoked using Fn + the key with the designated function as listed below.

Fn + F3 - Sleep - button/sleep SBTN 00000080 00000000 K
Fn + F4 - Switch to external display - video/switchmode VMOD 00000080 00000000
Fn + F8 - Battery information - button/battery BAT 00000080 00000000 K
Fn + F9 - Brightness down - video/brightnessdown BRTDN 00000087 00000000
Fn + F10 - Brightness up - video/brightnessup BRTUP 00000086 00000000

I went through the troubleshooting steps described at https://wiki.ubuntu.com/Hotkeys/Troubleshooting. In 14.10 none of these buttons work. Using acpi_listen I found that no events are fired in 14.10, but under 14.04 these buttons do indeed fire ACPI events and thus work correctly. The ACPI events listed above are fired in 14.04 using kernel 3.13 but are not fired under 14.10 using kernel 3.16.

Using xbacklight I can still change the brightness in 14.10, if that information is of any help.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: linux-image-3.16.0-25-generic 3.16.0-25.33
ProcVersionSignature: Ubuntu 3.16.0-25.33-generic 3.16.7
Uname: Linux 3.16.0-25-generic x86_64
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: giancarlo 1921 F.... lxpanel
CRDA: Error: [Errno 2] Datei oder Verzeichnis nicht gefunden: 'iw'
CurrentDesktop: LXDE
Date: Sun Nov 30 22:24:13 2014
HibernationDevice: RESUME=UUID=207b9cef-a34d-4cbe-b903-4e129ffc1789
InstallationDate: Installed on 2014-08-25 (97 days ago)
InstallationMedia: Lubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
Lsusb:
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
MachineType: Hewlett-Packard HP Compaq nx6310 (RH334ET#ABD)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-25-generic root=UUID=a3bac2e9-23b4-4965-b4fb-322b8037fca4 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.16.0-25-generic N/A
 linux-backports-modules-3.16.0-25-generic N/A
 linux-firmware 1.138
RfKill:
 0: phy0: Wireless LAN
  Soft blocked: no
  Hard blocked: no
SourcePackage: linux
UpgradeStatus: Upgraded to utopic on 2014-11-04 (26 days ago)
dmi.bios.date: 02/21/2008
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: 68YDU Ver. F.0E
dmi.board.name: 30AA
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 58.13
dmi.chassis.asset.tag: CNU645278T
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvr68YDUVer.F.0E:bd02/21/2008:svnHewlett-Packard:pnHPCompaqnx6310(RH334ET#ABD):pvrF.0E:rvnHewlett-Packard:rn30AA:rvrKBCVersion58.13:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP Compaq nx6310 (RH334ET#ABD)
dmi.product.version: F.0E
dmi.sys.vendor: Hewlett-Packard

[Brad Figg (brad-figg)]

This change was made by a bot.

[penalvch (penalvch)]

Marcus Pollice, thank you for reporting this and helping make Ubuntu better. Could you please test the latest upstream kernel available from the very top line at the top of the page (the release names are irrelevant for testing, and please do not test the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue.

If the test 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 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 exactly shown as:
kernel-fixed-upstream-3.18-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.

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

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.

[Marcus Pollice (marcus-pollice)]

I ran a test with kernel 3.18-rc7-vivid where the problem persists. I ran another test with 3.15.10-utopic where the functionality is as it was in the 3.13 release. So I assume the issue was introduced in the 3.16 series.

[penalvch (penalvch)]

Marcus Pollice, the next step is to fully commit bisect from kernel 3.13 to 3.16 in order to identify the last good kernel commit, followed immediately by the first bad one. This will allow for a more expedited analysis of the root cause of your issue. Could you please do this following https://wiki.ubuntu.com/Kernel/KernelBisection ? Please note, finding adjacent kernel versions is not fully commit bisecting.

Thank you for your understanding.

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

[Marcus Pollice (marcus-pollice)]

The offending commit is http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f82bdd0d77b6bf0dea08a1d957ab45d503f328b1

Since the BIOS of the laptop is from 2008 (but still the latest), it is obvious that after that change it won't work anymore. It would be interesting to know why upstream wanted to exclude pre-2009.

[Marcus Pollice (marcus-pollice)]

During the bisection I came across something that may be interesting with regard to the issue. While a freshly booted kernel with the issue has the functionality non-working, after going into standby and waking up it works as it did before. I verified that also with the 3.18 release kernel. This information may later be helpful when it comes to actually fixing the issue.

[penalvch (penalvch)]

Marcus Police, and lastly could you please test the latest mainline kernel 3.19-rc1 and advise to the results?

[Marcus Pollice (marcus-pollice)]

Done, same as with 3.18.

[penalvch (penalvch)]

Marcus Pollice, the issue you are reporting is an upstream one. Could you please report this problem to the appropriate mailing list (linux-input) by following the instructions verbatim at https://wiki.ubuntu.com/Bugs/Upstream/kernel ?

Please provide a direct URL to your e-mail to the mailing list once you have made it so that it may be tracked via http://vger.kernel.org/vger-lists.html .

Thank you for your understanding.

[Marcus Pollice (marcus-pollice)]

Shouldn't it rather go to platform-driver-x86 given the hp-wmi driver seems to be the culprit as the bisection has shown?

As the instructions advise I would CC the maintainer and the committer (since it is a regression) as well.

[penalvch (penalvch)]

Marcus Pollice, while linux-input would apply here, yes, platform-driver-x86 would be a better choice.