Bug 31402

Summary:	Diminished brightness at startup
Product:	Drivers	Reporter:	Guilherme Salazar (guilhermesalazar)
Component:	Video(DRI - Intel)	Assignee:	drivers_video-dri-intel (drivers_video-dri-intel)
Status:	RESOLVED CODE_FIX
Severity:	normal	CC:	akpm, daniel, florian, jbarnes, maciej.rutecki, mjg59-kernel, rjw
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	2.6.38	Subsystem:
Regression:	Yes	Bisected commit-id:
Bug Depends on:
Bug Blocks:	27352

Description Guilherme Salazar 2011-03-18 16:29:12 UTC

Hi,
I've installed the latest kernel version to test the news. But I've a problem with this version.
When I turn on my laptop the brightness appears diminished. If I go to the bios setup and restart, everything works fine.
Now I'm using version 2.6.37.4 without any problem.

So, I don't know what information details do you need to help me. But the video device is a Intel Integrated Graphics (i5 series), and the module is the i915.
If additional information is needed, I'll send it.

Thank you very much for your attention.
Sorry for my poor english.

Comment 1 Matthew Garrett 2011-03-18 21:36:05 UTC

I suspect this was the change to the combined mode backlight handling - I think it's a problem with i915 rather than anything in the general backlight or acpi code.

Comment 2 Guilherme Salazar 2011-03-20 14:28:34 UTC

Does anyone have any idea that might help?
I'm using a DELL Inspiron 15R Laptop, and as I said a Intel Integrated Graphics (Processor Intel Core i5).

I'm excited to test the news of this version.
Thank you! :)

Comment 3 Rafael J. Wysocki 2011-03-27 22:59:46 UTC

On Monday, March 28, 2011, Guilherme Salazar wrote:
> Hello,
> first I would like to thank everyone who work in kernel development.
> 
> I've installed the version 2.6.38 and this bug appears. After a lot of
> trying,
> I've installed back the version 2.6.37-4. On last week, I installed the
> new 2.6.38-1, and the bug remains. Now I'm running the 2.6.37-5 with no
> problem.

Comment 4 Guilherme Salazar 2011-03-28 03:03:30 UTC

Still in 2.6.38-2.

I am ready to help you find the problem. Just tell me what to do.
I suspect that I'm doing something wrong way.
I'll compile again and post results here.


Good week for all.

Comment 5 Guilherme Salazar 2011-04-01 04:18:06 UTC

Hello.
Like I said, I've tested it again and the problem wasn't solved, unfortunately. Is it possible that it is because I'm using a config file of 2.6.37 version?



Cheers! :)

Comment 6 Guilherme Salazar 2011-04-01 05:03:00 UTC

An interesting detail is that even with this problem the function keys work. Thus, I can change the brightness during boot. I've tested now with 2.6.39-rc1 too.

Comment 7 Guilherme Salazar 2011-05-02 22:55:57 UTC

I have tested 2.6.38.5 and the problem stills chasing me.

Comment 8 Florian Mickler 2011-05-10 18:25:47 UTC

Maybe you are hitting the same issue as bug #31522 ? 
So you could try the patch from https://patchwork.kernel.org/patch/743162/
and see if it works for you too.

Comment 9 Guilherme Salazar 2011-05-11 03:37:51 UTC

Hi Florian,
I've tested it, but doesn't work for me.

Thanks anyway.

Comment 10 Daniel Vetter 2012-03-25 13:36:43 UTC

Please retest with 3.3 and report back whether this is still an issue for you. Thanks.

Comment 11 Jesse Barnes 2012-04-18 21:05:34 UTC

Please re-open if this is still an issue.