Bug 27812

Summary:	2.6.38-rc2: acpi backlight control missing
Product:	ACPI	Reporter:	Maciej Rutecki (maciej.rutecki)
Component:	Power-Video	Assignee:	acpi_power-video
Status:	CLOSED DUPLICATE
Severity:	normal	CC:	chris, florian, maciej.rutecki, paulo.miguel.dias, rjw, rui.zhang, thomas
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	2.6.38-rc2	Subsystem:
Regression:	Yes	Bisected commit-id:
Bug Depends on:
Bug Blocks:	27352

Description Maciej Rutecki 2011-01-29 13:57:11 UTC

Subject    : 2.6.38-rc2: acpi backlight control missing
Submitter  : Thomas Meyer <thomas@m3y3r.de>
Date       : 2011-01-22 10:49
Message-ID : 1295693349.2120.3.camel@localhost.localdomain
References : http://marc.info/?l=linux-kernel&m=129569353414755&w=2

This entry is being used for tracking a regression from 2.6.37. Please don't
close it until the problem is fixed in the mainline.

Caused by:

commit 677bd810eedce61edf15452491781ff046b92edc
Author: Zhang Rui <rui.zhang@intel.com>
Date:   Mon Dec 6 15:04:21 2010 +0800

    ACPI video: remove output switching control

First-Bad-Commit : 677bd810eedce61edf15452491781ff046b92edc

Comment 1 Paulo Dias 2011-02-01 19:30:25 UTC

I can confirm this, modpring video and output.ko doesnt activate the /proc/acpi/etc... brightness device.

this is with a hp pavilion dv7 and kernel Linux hydra 2.6.38-020638rc3-generic #201102010912 SMP Tue Feb 1 09:14:19 UTC 2011 x86_64 GNU/Linux

Comment 2 Rafael J. Wysocki 2011-02-01 23:52:32 UTC

Please test the patch in bug #27702.

Comment 3 Zhang Rui 2011-02-09 02:35:29 UTC

ping

Comment 4 Paulo Dias 2011-02-09 16:31:32 UTC

i patched kernel 2.6.38 rc4 stock with the aforementioned patch, backlight works now as expected, great job :)

Comment 5 Florian Mickler 2011-02-09 23:03:32 UTC

Thank you for reporting your issue.

*** This bug has been marked as a duplicate of bug 27702 ***

Comment 6 Florian Mickler 2011-02-09 23:04:04 UTC

Or more exactly testing the patch.