Comment 0 for bug 810093

I have a Samsung N220 plus. The backlight of the laptop often starts flickering (switching very fast between 2 brightness levels) when gnome tries to reduce the screen brightness (automatically after some time) to save power. This problem also occurs if you press more and less screen brightness at the same time.
I think it could be a problem with the sabi Bios interaction (samsung-laptop.c), because "linux on my samsung" also had this Problem with theier samsung-backlight module:
http://www.voria.org/forum/viewtopic.php?t=625&p=5148
and they solved it by interfacing the backlight via pci.
I tried to enable debug modus of samsung-laptop module, but I didn't get any more output on error. Dmesg only says (a lot of times):
ACPI: Failed to switch the brightness
I'll provide more informations if needed.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: linux-image-3.0.0-5-generic 3.0.0-5.6
ProcVersionSignature: Ubuntu 3.0.0-5.6-generic 3.0.0-rc7
Uname: Linux 3.0.0-5-generic i686
NonfreeKernelModules: wl
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
AplayDevices:
 **** List of PLAYBACK Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: flexxxv 1405 F.... pulseaudio
CRDA: Error: [Errno 2] Datei oder Verzeichnis nicht gefunden
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf0400000 irq 47'
   Mixer name : 'Realtek ALC269'
   Components : 'HDA:10ec0269,144dc072,00100004'
   Controls : 14
   Simple ctrls : 9
Date: Wed Jul 13 20:56:28 2011
HibernationDevice: RESUME=UUID=9f00b9b2-337b-4462-8157-50d16690f634
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Alpha i386 (20110705.1)
MachineType: SAMSUNG ELECTRONICS CO., LTD. N150P/N210P/N220P
ProcEnviron:
 LANGUAGE=de:en
 PATH=(custom, user)
 LANG=de_DE.UTF-8
 LC_MESSAGES=de_DE.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-5-generic root=UUID=1f2007e5-9b44-4cb5-a64a-4c2bf8dbda42 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.0.0-5-generic N/A
 linux-backports-modules-3.0.0-5-generic N/A
 linux-firmware 1.56
SourcePackage: linux
StagingDrivers: brcmsmac brcmutil
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/30/2010
dmi.bios.vendor: Phoenix Technologies Ltd.
dmi.bios.version: 01KY.M008.20100430.RHU
dmi.board.asset.tag: SAMSUNG
dmi.board.name: N150P/N210P/N220P
dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.board.version: Not Applicable
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvr01KY.M008.20100430.RHU:bd04/30/2010:svnSAMSUNGELECTRONICSCO.,LTD.:pnN150P/N210P/N220P:pvrNotApplicable:rvnSAMSUNGELECTRONICSCO.,LTD.:rnN150P/N210P/N220P:rvrNotApplicable:cvnSAMSUNGELECTRONICSCO.,LTD.:ct10:cvrN/A:
dmi.product.name: N150P/N210P/N220P
dmi.product.version: Not Applicable
dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD.