Bug 737108

Summary: Backlight on Samsung N127 laptop blinks after update to kernel-2.6.40.3
Product: [Fedora] Fedora Reporter: Kirin Yuri <kirin.yuri>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: low Docs Contact:
Priority: unspecified    
Version: 15CC: gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, mangoo, yann
Target Milestone: ---   
Target Release: ---   
Hardware: i686   
OS: Linux   
Whiteboard:
Fixed In Version: kernel-2.6.41.1-1.fc15 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-11-17 18:28:36 EST Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Description Kirin Yuri 2011-09-09 12:11:32 EDT
Description of problem:
After update to kernel-2.6.40.3-0.fc15.i686 a backlight of my laptop Samsung N127 starts to blink after authorization in KDM. Difference between nice-working kernel-2.6.40-4.fc15.i686 and kernel-2.6.40.3-0.fc15.i686 is samsung_laptop kernel module. /var/log/messages is full off:
"samsung_laptop: SABI set command 0x01 failed with completion flag 0xaa and data 0xff"

Version-Release number of selected component (if applicable):
kernel-2.6.40.4-5.fc15.i686
kernel-2.6.40.3-0.fc15.i686

How reproducible:
Every boot.

Steps to Reproduce:
1. Get Samsung N127 laptop
2. Install Fedora 15 and update kernel to kernel-2.6.40.3
3. Install KDE and log into KDM.
  
Actual results:
Backlight starts to blink few times in a second. After a some time it stops, but starts again after manual brightness regulation.

Expected results:
Backlight not blinks.
Comment 1 Tomasz Chmielewski 2011-09-13 08:16:42 EDT
I see exactly the same behaviour (blinking) on Samsung N130.
Comment 2 Chuck Ebbert 2011-09-14 06:05:51 EDT
The fix for this seems to have fallen into a black hole:

https://lkml.org/lkml/2011/4/20/1
https://lkml.org/lkml/2011/5/11/548
Comment 3 Chuck Ebbert 2011-10-24 21:39:16 EDT
See:
https://bugzilla.redhat.com/show_bug.cgi?id=747560#c3

for some possible workarounds.
Comment 4 Chuck Ebbert 2011-10-24 22:42:18 EDT
Patch from comment 2 has been applied to the f15 kernel and should be in the next update (probably 2.6.40.8).
Comment 5 Fedora Update System 2011-10-27 10:12:40 EDT
kernel-2.6.40.8-2.fc15 has been submitted as an update for Fedora 15.
https://admin.fedoraproject.org/updates/kernel-2.6.40.8-2.fc15
Comment 6 Fedora Update System 2011-10-29 20:35:25 EDT
Package kernel-2.6.40.8-2.fc15:
* should fix your issue,
* was pushed to the Fedora 15 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing kernel-2.6.40.8-2.fc15'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2011-15108
then log in and leave karma (feedback).
Comment 7 Yann Droneaud 2011-10-31 11:31:21 EDT
(In reply to comment #6)
> Package kernel-2.6.40.8-2.fc15
> * should fix your issue,

It doesn't fix flickering problem reported in bug 747560 (on Samsung n210).
Comment 8 Fedora Update System 2011-11-01 15:58:51 EDT
kernel-2.6.40.8-4.fc15 has been submitted as an update for Fedora 15.
https://admin.fedoraproject.org/updates/kernel-2.6.40.8-4.fc15
Comment 9 Tomasz Chmielewski 2011-11-01 16:28:52 EDT
BTW, was this pushed to the upstream kernel (the coming 3.2-rc*, or is there already perhaps)?
Comment 10 Josh Boyer 2011-11-02 12:15:56 EDT
(In reply to comment #9)
> BTW, was this pushed to the upstream kernel (the coming 3.2-rc*, or is there
> already perhaps)?

Yes, it's in Linus' tree already.
Comment 11 Fedora Update System 2011-11-11 19:07:55 EST
kernel-2.6.41.1-1.fc15 has been submitted as an update for Fedora 15.
https://admin.fedoraproject.org/updates/kernel-2.6.41.1-1.fc15
Comment 12 Fedora Update System 2011-11-17 18:28:36 EST
kernel-2.6.41.1-1.fc15 has been pushed to the Fedora 15 stable repository.  If problems still persist, please make note of it in this bug report.