Bug 293047

Summary:	sys-kernel/gentoo-sources: Samsung N510 / nvidia ION display backlight control not working
Product:	Gentoo Linux	Reporter:	Jens Stutte <jens>
Component:	[OLD] Core system	Assignee:	Gentoo Kernel Bug Wranglers and Kernel Maintainers <kernel>
Status:	RESOLVED NEEDINFO
Severity:	normal	CC:	brezell
Priority:	High
Version:	unspecified
Hardware:	x86
OS:	Linux
URL:	http://bbs.archlinux.org/viewtopic.php?pid=655144
Whiteboard:
Package list:		Runtime testing required:	---

Description Jens Stutte 2009-11-13 15:52:41 UTC

The kernel does not create any /proc/acpi/video folder for the nvidia ION chipset. As a consequence, backlight control will not work.

For details and a patch vs. vanilla kernel, please refer to the Arch linux forum entry I pasted under URL.


Reproducible: Always

Steps to Reproduce:
1. Buy Samsung N510 (or other ION netbook)
2. Install gentoo, install nvidia drivers
3. check /proc/acpi/video

Actual Results:  
/proc/acpi/video is empty


As a patch seems to already exist, I would be glad if the patchset of gentoo-sources could include this one.

Comment 1 Jens Stutte 2009-11-13 15:54:00 UTC

I forgot to mention: This happens both with kernel 2.6.30-r8 as with 2.6.31.r2.

Comment 2 Jens Stutte 2009-11-16 08:48:47 UTC

I applied this patch successfully on 2.6.31-r2 kernel tree (but I'v seen that video.c and video_detect.c are equal also in 2.6.30-r8), now backlight control works for me. Obviously I do not know, if this may break something for anyone else.

Comment 3 Jens Stutte 2009-11-24 13:18:50 UTC

It also seems that ubuntu karmic already includes this patch in its default kernel. At least on ubuntu karmic the backlight control works, as reported by others.

Comment 4 Brezell 2009-11-26 23:31:11 UTC

FWIW - just patched my gentoo-sources 2.6.31-gentoo-r5 with the patch mentioned in the archlinux forum, and now backlight control works with kde 4.3.1. 
Fn+Up/Dn keys for brightness control don'twork yet, but that's unrelated to this issue.

Comment 5 Jens Stutte 2009-11-27 13:21:12 UTC

(In reply to comment #4)
> FWIW - just patched my gentoo-sources 2.6.31-gentoo-r5 with the patch mentioned
> in the archlinux forum, and now backlight control works with kde 4.3.1. 
> Fn+Up/Dn keys for brightness control don'twork yet, but that's unrelated to
> this issue.
> 

OT: For hints on the function key problems you may try the tips for NC10 in this forum: http://www.voria.org/forum/. I had not yet the time to check it out, though.

Comment 6 Wormo (RETIRED) gentoo-dev

2009-11-30 02:35:13 UTC

Thanks for the pointer to patch for this issue, assigning to kernel team.

Comment 7 Mike Pagano gentoo-dev

2009-12-07 14:00:51 UTC

We'll keep on eye on this and wait for the fix to make upstream development kernel repository.

Comment 8 Mike Pagano gentoo-dev

2010-01-11 01:04:21 UTC

It looks like the patch reference is in linux-2.6.32.  Can you test with that one and let us know the results.

Comment 9 Jens Stutte 2010-02-05 09:49:49 UTC

(In reply to comment #8)
> It looks like the patch reference is in linux-2.6.32.  Can you test with that
> one and let us know the results.
> 

Sorry, I am very short of time in this period. I will try it ASAP.

Comment 10 Jens Stutte 2010-02-09 21:16:05 UTC

OK, I finally found the time to test. gentoo-sources-2.6.32-r4 does the job. (probably any 2.6.32 kernel will do). Thanx!

Comment 11 Jens Stutte 2010-02-09 21:18:01 UTC

(In reply to comment #10)
> OK, I finally found the time to test. gentoo-sources-2.6.32-r4 does the job.
> (probably any 2.6.32 kernel will do). Thanx!
> 
PS: To me it's closed then, but I'm not familiar with your habits here so I left it RESOLVED NEEDINFO by now.