Bug 8918 - backlight brightness does not change
Summary: backlight brightness does not change
Status: RESOLVED DUPLICATE of bug 7299
Alias: None
Product: Mageia
Classification: Unclassified
Component: RPM Packages (show other bugs)
Version: Cauldron
Hardware: All Linux
Priority: Normal normal
Target Milestone: ---
Assignee: Thomas Backlund
QA Contact:
URL:
Whiteboard:
Keywords: UPSTREAM
Depends on:
Blocks:
 
Reported: 2013-01-31 21:17 CET by José Jorge
Modified: 2013-07-24 12:09 CEST (History)
1 user (show)

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Source RPM: kernel
CVE:
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Description José Jorge 2013-01-31 21:17:45 CET 
While brightness worked with MGA2, with MGA3 kernel 3.8 it does not anymore.
This is because the kernel tells acpi that it is Windows8 : adding the following text to grub kernel line fixes the bug.

acpi_osi="!Windows 2012"

Now can we blacklist this in MGA3 kernels like int his bug report?

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1098216/comments/22
Comment 1 José Jorge 2013-01-31 21:20:45 CET 
To make it clear, this is a BIOS bug, as 

/sys/class/backlight/acpi_video0/max_brightness indicates 7 with bug workaround, hile it indicates 100 without. Only levels 1 to 7 change backlight brightness.
Manuel Hiebel 2013-02-01 01:07:51 CET

Keywords: (none) => UPSTREAM
Assignee: bugsquad => tmb

Comment 2 Oleg Kitain 2013-07-20 11:12:32 CEST 
Is there any difference between this and bug 7299?

CC: (none) => oktain

Comment 3 José Jorge 2013-07-24 12:09:08 CEST 
It seems not, except the workaround was different.

*** This bug has been marked as a duplicate of bug 7299 ***

Status: NEW => RESOLVED
Resolution: (none) => DUPLICATE
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