Do not samsung_backlight module for certain samsung laptops

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I purchased a new laptop whose product name is: 90X3A.  Ubuntu 10.10 supports 
backlight control out of the box without any hack.

To control the fan speed, I installed easy-slow-down-manager.  Fan control 
works great, but it seems to interfere with the existing backlight control 
function.  If I set acpi_backlight=vendor, backlight control does not work at 
all (i.e. full brightness).

Perhaps samsung_backlight module should not be loaded automatically for this 
specific model?  To work around this issue, I simply removed 
samsung_backlight.c from the build, and it fixed the problem.

Original issue reported on code.google.com by trus...@gmail.com on 30 Mar 2011 at 6:43

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One more thing: easy_wifi_kill does not work with 90X3A.

Original comment by trus...@gmail.com on 30 Mar 2011 at 6:45

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easy_backlight does work though.

Original comment by trus...@gmail.com on 30 Mar 2011 at 6:45

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For Ubuntu 10.10 option 'acpi_backlight=vendor' instructs kernel to use custom 
backlight driver; remove this option to use out of the box one.

Thank you for letting now wifi_kill does not work for you. 
Seems Samsung has changed sabi specifications for your laptop model. Cannot 
provide you with better support till I find new documentation, sorry. 

Original comment by SergeyK...@gmail.com on 4 Apr 2011 at 3:54

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No problem.  Thanks for a quick reply.

What's interesting is that the backlight control stops working when 
samsung_backlight module is loaded even if acpi_backlight is set to 'video' 
instead of 'vendor'.  It means samsung_backlight module does affect the 
brightness control even if the module is not used actually.  To fix the 
problem, samsung_backlight module should fail to load itself if product name is 
90X3A.

Original comment by trus...@gmail.com on 4 Apr 2011 at 12:15