I can do that but im using the same kernel 3.19. and have the same problem..
maybe I'll reinstall this computer fist don't know what I've done with it.
It's poorly or experimental configured so I'll think you get a better
report if this computer were more default configured.

My idea of the problem is that some acpi backligt driver is not
communicating with the hp_wmi driver.
the hp_wmi driver need to bee updated I think. there is a lot of other key
not working in the hp_wmi module and sometimes random output.

2015-08-03 4:22 GMT+02:00 Chris <email address hidden>:

> For report, see :
>  https://bugs.launchpad.net/ubuntu/+source/linux-lts-utopic/+bug/1480747
>
> An idea of problem?
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1448485
>
> Title:
>   [Compaq Presario CQ60-300EO Notebook PC] kernel doesn't recognize
>   backlight fn keys
>
> Status in linux package in Ubuntu:
>   Incomplete
>
> Bug description:
>   I'm using Ubuntu 15.04 and fn+f7 and fn+f8 use to lower and higher the
> brightness of the screen.
>   In slackware using kernel 3.14.33 those keys works and give output from
> acpi_listen.
>   In kernel 3.16 to 4.0 those keys don't work and acpi_listen outputs
> nothing.
>
>   I expected fn+f7 and fn+f8 to work
>
>   https://bugzilla.kernel.org/show_bug.cgi?id=60670
>   This bug my be related
>
>   This is my first bug report.
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 15.04
>   Package: linux-image-3.19.0-15-generic 3.19.0-15.15 [modified:
> boot/vmlinuz-3.19.0-15-generic]
>   ProcVersionSignature: Ubuntu 3.19.0-15.15-lowlatency 3.19.3
>   Uname: Linux 3.19.0-15-lowlatency x86_64
>   ApportVersion: 2.17.2-0ubuntu1
>   Architecture: amd64
>   AudioDevicesInUse:
>    USER        PID ACCESS COMMAND
>    /dev/snd/controlC0:  marbangens   1334 F.... pulseaudio
>   CurrentDesktop: Unity
>   Date: Sat Apr 25 17:04:30 2015
>   HibernationDevice: RESUME=UUID=22f95b90-3ec0-4b6d-9e76-13042dc0a290
>   InstallationDate: Installed on 2015-04-23 (1 days ago)
>   InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
>   MachineType: Hewlett-Packard Compaq Presario CQ60 Notebook PC
>   ProcFB: 0 nouveaufb
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-15-lowlatency
> root=UUID=d4f39d6b-137e-4248-81cb-ce920cdee909 ro quiet splash vt.handoff=7
>   RelatedPackageVersions:
>    linux-restricted-modules-3.19.0-15-lowlatency N/A
>    linux-backports-modules-3.19.0-15-lowlatency  N/A
>    linux-firmware                                1.143
>   RfKill:
>    0: phy0: Wireless LAN
>         Soft blocked: no
>         Hard blocked: no
>   SourcePackage: linux
>   UdevLog: Error: [Errno 2] Filen eller katalogen finns inte:
> '/var/log/udev'
>   UpgradeStatus: No upgrade log present (probably fresh install)
>   dmi.bios.date: 08/18/2009
>   dmi.bios.vendor: Hewlett-Packard
>   dmi.bios.version: F.54
>   dmi.board.name: 303C
>   dmi.board.vendor: Wistron
>   dmi.board.version: 08.60
>   dmi.chassis.type: 10
>   dmi.chassis.vendor: Wistron
>   dmi.chassis.version: N/A
>   dmi.modalias:
> dmi:bvnHewlett-Packard:bvrF.54:bd08/18/2009:svnHewlett-Packard:pnCompaqPresarioCQ60NotebookPC:pvrF.54:rvnWistron:rn303C:rvr08.60:cvnWistron:ct10:cvrN/A:
>   dmi.product.name: Compaq Presario CQ60 Notebook PC
>   dmi.product.version: F.54
>   dmi.sys.vendor: Hewlett-Packard
>
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>