LCD backlight does not turn off in X.org using xset with S3 Savage

[Ashley Hooper]

Binary package hint: xserver-xorg-driver-savage

(I have been lurking on various other Launchpad bugs for some time but now as it seems this bug is appearing in various X.org drivers, and Launchpad bugs are being logged for each specific X.org driver, I'm going to add my driver here)

The backlight has not switched off on my Toshiba Portege 3480CT for several Ubuntu versions. This is a concern for me as it is needlessly wasting energy, and my battery power when I'm not on AC mains.

The backlight is controllable via vbetool, i.e. "sudo vbetool dpms off", "standby" etc all work properly.
[lspci]
00:00.0 Host bridge [0600]: Intel Corporation 82440MX Host Bridge [8086:7194] (rev 01)
     Subsystem: Toshiba America Info Systems Device [1179:0001]
00:04.0 VGA compatible controller [0300]: S3 Inc. 86C270-294 Savage/IX-MV [5333:8c12] (rev 13)
     Subsystem: Toshiba America Info Systems Device [1179:0001]

[Bart Kroon (tarmack)]

I'm afraid the problem is in the way laptops cope with backlight management. Usualy the video chip is not the one signaling the backlight off but the bios deals with powermanagement. This is the reason why vbetool does work and DPMS from X.org doesn't, vbetool uses realmode but X.org isn't able to do this as it runs with the wrong permissions.

Please correct me if i'm wrong, this is just what my conclusion is from what i have seen.

I do have the same problem on a savage chip in a Toshiba Satallite 4200 series.
BTW I'm running Hardy upgraded from Gutsy

[Bart Kroon (tarmack)]

Coming to think of it, perhaps this should be a HAL bug. As far as I understand the HAL daemon is responsible for most of the power management and in my opinion should be the one to deal with panel power management too.

This is just my two cents, kick me if you don't agree.

[Bryce Harrington (bryce)]

Hi ash-hooper,

Thank you for taking the time to report this bug and helping to make Ubuntu better. You reported this bug a while ago and there hasn't been any activity in it recently. We were wondering is this still an issue for you? Can you try with the latest development release of Ubuntu? (ISOs are available from cdimage.ubuntu.com)

If it remains an issue, could you also attach a new /var/log/Xorg.0.log?
Thanks in advance.

The output of lspci -vvnn would also be worth having.

[Ashley Hooper (ash-hooper)]

xset dpms force off
xset dpms force standby
etc...

...all still fail to switch off the backlight on my notebook. I have done numerous fresh installs of Ubuntu since the problem first appeared with Feisty Fawn, and have tested with both Hardy Heron & Intrepid Ibex.

Here is the 2nd of the 2 files you asked for.

For anyone with the same problem, there's an interesting page with a possible workaround here:

http://www.shallowsky.com/linux/x-screen-blanking.html

[etali (etali)]

Is this still an issue for you in 9.04 or 9.10?

[Ashley Hooper (ash-hooper)]

Yes, the backlight has never worked on my S3 Savage since about Hoary
Hedgehog :(

I have tried everything and have to write fancy scripts that call
vbetool, which is not user-friendly or conveient... and it only
works then if I close the laptop lid anyway,...

On Sat, Dec 12, 2009 at 4:13 PM, etali <email address hidden> wrote:
> Is this still an issue for you in 9.04 or 9.10?
>
> --
> LCD backlight does not turn off in X.org using xset with S3 Savage
> https://bugs.launchpad.net/bugs/158404
> You received this bug notification because you are a direct subscriber
> of the bug.
>

[Bryce Harrington (bryce)]

[This is an automatic notification.]

Hi Ashley,

This bug was reported against an earlier version of Ubuntu, can you
test if it still occurs on Lucid?

Please note we also provide technical support for older versions of
Ubuntu, but not in the bug tracker. Instead, to raise the issue through
normal support channels, please see:

    http://www.ubuntu.com/support

If you are the original reporter and can still reproduce the issue on
Lucid, please run the following command to refresh the report:

  apport-collect 158404

If you are not the original reporter, please file a new bug report, so
we can work with you as the original reporter instead (you can reference
bug 158404 in your report if you think it may be related):

  ubuntu-bug xorg

If by chance you can no longer reproduce the issue on Lucid or if you
feel it is no longer relevant, please mark the bug report 'Fix Released'
or 'Invalid' as appropriate, at the following URL:

  https://bugs.launchpad.net/ubuntu/+bug/158404

[Ashley Hooper (ash-hooper)]

Hello Bryce. I don't hold out much hope of this bug being fixed anytime soon, and probably won't have access to my laptop to test it for some months.

When I have time and access to my laptop again, I will be pursuing this matter again. This is likely to be in a few months' time.

[rusivi2 (rusivi2-deactivatedaccount)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The package your reporting is updated and the issue should be reproducible with the live environment of the Desktop CD development release - Maverick Meerkat. It would help us greatly if you could test with it so we can work on getting it fixed in the next release of Ubuntu. You can find more about the development release at http://www.ubuntu.com/testing/. Thanks again and we appreciate your help.

[Launchpad Janitor (janitor)]

[Expired for xserver-xorg-video-savage (Ubuntu) because there has been no activity for 60 days.]