Notebook Ambient Light Sensor Disfunction

[1nxr0x]

When attempting to run Ubuntu or it's variants on an Asus notebook which has an ambient light sensor, the sensor does not work correctly and the screen remains too dim to be productive or truly usable. My particular Asus notebook that is affected by this bug is a model M50Sv.

There are various proposed fixes published on the net, but they all either do not work as described, or they are only temporary and do not carry over ofter re-booting.

This bug essentially makes using Ubuntu and it's variants utterly impractical and unproductive. The eye strain caused by this bug is unbearable.

This bug is accruing on other makes and models of notebooks which incorporate an ambient light sensor as well.

[Karim A. Nassar (karimofthecrop)]

Me too on asus main board. I can provide diagnostics for a developer, if I knew what to provide....

[Karim A. Nassar (karimofthecrop)]

The workaround that works for me is: http://ubuntuforums.org/showthread.php?t=666372

[Adi Roiban (adiroiban)]

Can you specify what Ubuntu and kernel version are you using

[Karim A. Nassar (karimofthecrop)]

ubuntu 8.04

root@wiggly:~# uname -a
Linux wiggly 2.6.24-19-generic #1 SMP Wed Aug 20 22:56:21 UTC 2008 i686
GNU/Linux

On Tue, Sep 16, 2008 at 03:04, Adi Roiban <email address hidden> wrote:

> Can you specify what Ubuntu and kernel version are you using
>
> ** Changed in: linux (Ubuntu)
> Sourcepackagename: None => linux
>
> --
> Notebook Ambient Light Sensor Disfunction
> https://bugs.launchpad.net/bugs/251278
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Darlan Cavalcante (darcamo)]

I can confirm this bug on an Asus M70 notebook.

After desactivating the light sensor with
echo 0 > /sys/devices/platform/asus-laptop/ls_switch
I can change the brightness with the notebook keys, but I have to desactivate the light sensor everytime I reboot.

Ideally, there should be possible to change the brightness with the light sensor activated and the configuration should be remembered after a reboot.

Is it possible to at least desactivate the light sensor by default while the problem is not fixed so that users do not need to google around how to change brightness? It is better not to have the light sensor working than not been able to change brightness (with a too dark defalt value).

[Darlan Cavalcante (darcamo)]

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/219463
and
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/222171
seen to be duplicates of this bug.

[penalvch (penalvch)]

1nxr0x, 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? Can you try with the latest development release of Ubuntu? ISO CD images are available from http://cdimage.ubuntu.com/releases/ .

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

apport-collect -p linux <replace-with-bug-number>

Also, if you could test the latest upstream kernel available that would be great. It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag. This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text.

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'.

Please let us know your results. Thanks in advance.

[Launchpad Janitor (janitor)]

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

[Tessa (unit3)]

Just updating this bug, since I'm running into it on my UX302LG. It looks like it should be fixed in future kernel releases, so it'd be useful to know if the patches mentioned here are actually in the next Ubuntu release (14.10):

https://bugzilla.kernel.org/show_bug.cgi?id=70421

In the mean time, the alternate driver from github seems to work:

https://github.com/danieleds/Asus-Zenbook-Ambient-Light-Sensor-Controller

[penalvch (penalvch)]

Graeme, 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 the default Ubuntu 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.

As well, please do not announce in this report you created a new bug report.

Thank you for your understanding.

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