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infyquest

Member

Registered: 2012-11-20

Posts: 3

Brighness issue with dell e1705 laptop

I am using Dell E1705 laptop with nvidia Geforce Go 7900 GS with Linux Kernel 3.6.6 and nouveau 1.0.4

I am unable to change the brightness on the laptop. I believe I might go blind if the situation continues for long.

I have tried changing the acpi_backlight, it does not work

currently the directory in   /sys/class/backlight/ is acpi_video0

the values for actual_brightness is 4, brightness is 4 and max_brightness is 7

I cannot set these value of actual_brightness manually

I believe there is a backlight issue with kernel or nouveau

I need a solution for this....or i will become blind, my eyes are already stressed/strained

mhertz

Member

From: Denmark

Registered: 2010-06-19

Posts: 681

Re: Brighness issue with dell e1705 laptop

Try as root(not with sudo!):

echo 1 > /sys/class/backlight/acpi_video0/brightness

change the 1 to whatever you want...

Also try adding 'acpi_osi=Linux' kernel parameter, which on some systems can make the function keys for brightness work...

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: Brighness issue with dell e1705 laptop

Hopefully Gentoo wiki article will show info about why your BIOS isn't cooperating.

Also try Nvidia's driver instead of nouveau, to see if there's an improvement.

infyquest

Member

Registered: 2012-11-20

Posts: 3

Re: Brighness issue with dell e1705 laptop

Try as root(not with sudo!):

echo 1 > /sys/class/backlight/acpi_video0/brightness

change the 1 to whatever you want...

Also try adding 'acpi_osi=Linux' kernel parameter, which on some systems can make the function keys for brightness work...

tried does not work.
In the first case, it goes bright and turns back to normal, all in 1 sec.
the second one does not work,

I would try to get the acpi dump and modify it
any help would be appreciated

infyquest

Member

Registered: 2012-11-20

Posts: 3

Re: Brighness issue with dell e1705 laptop

$ dmesg|grep 'ACPI: Video'
[   22.200400] ACPI: Video Device [VID] (multi-head: yes  rom: no  post: no)
$ lspci |grep VGA
01:00.0 VGA compatible controller: NVIDIA Corporation G71 [GeForce Go 7900 GS] (rev a1)
how do i attach my dsdt file, I see that my VID devices are on 0x00 and 0x00020000 address