Pommed and brightness control not working

**khronoslynx** · October 12th, 2010

@_mario_:
My driver must not be loaded correctly. Terminal tells me there is no such file or directory as "/sys/class/mbp_backlight/brightness"

Maybe thats the root of my problem. Any advice on checking if my driver is loaded correctly?]

Edit:
after looking through some older forum posts (From late 08/early 09) I saw a tip to try running
sudo rmmod mbp_nvidia_bl
sudo modprobe mbp_nvidia_bl

cat /sys/class/backlight/mbp_backlight/brightness

in the terminal. Problem occurred when terminal returned ERROR: Module mbp_nvidia_bl does not exist in /proc/modulesupdated it back to the latest version, and am about to restart and see if I still get said errors
I just

Edit 2:
Still nothing. Same error occurs both with echo and rmmod

**CalaverX11** · October 13th, 2010

Same issue here. I am about to re-install Maverick (now that it's in official release) and try again. After updating the RC I was unable to regain brightness control; I hadn't tried the previously-mentioned steps yet, but I will if it's still broken.

**khronoslynx** · October 14th, 2010

I now have the brightness keys to change the brightness "bar" but not the actual LCD brightness. Echoing values to /sys/class/mbp_backlight/brightness still produces the same error

**wids** · October 20th, 2010

https://bugs.launchpad.net/mactel-support/+bug/662420

**kokoklems** · December 3rd, 2010

Hello,

I have maverick (2.6.35-23-generic) installed on my alu iMac 9,1, with a nVidia graphic card: GeForce 9400.

I am struggling for 2 weeks now because I can't decrease the brightness of my screen...
I installed mbp-nvivia-bl-dkms from mactel ppa, but I am not able to load the mbp_nvidia_bl module...

Code:

sudo modprobe mbp_nvidia_bl
FATAL: Error inserting mbp_nvidia_bl (/lib/modules/2.6.35-23-generic/updates/dkms/mbp_nvidia_bl.ko): No such device

Although, my /sys/class/backlight/ directory is empty...

What should I try next?

Thank you very much guys for any help you can provide...

**_mario_** · December 3rd, 2010

Originally Posted by kokoklems

I have maverick (2.6.35-23-generic) installed on my alu iMac 9,1, with a nVidia graphic card: GeForce 9400.

the driver doesn't support iMac models and, hence, doesn't load. in fact, we don't know whether the driver works on this machine at all. i can provide a patched version, if you like to try.

ciao,
Mario

**kokoklems** · December 3rd, 2010

Indeed, I would like to give it a try if possible. Thank you for your help. Hope it will work...

**_mario_** · December 10th, 2010

Originally Posted by kokoklems

Indeed, I would like to give it a try if possible. Thank you for your help. Hope it will work...

sorry, i almost forgot this thread. but if you still like to test, i attached a small program, that implements the same interfaces the driver uses. you can compile it like this:

Code:

$ gunzip apple-backlight.cpp.gz
$ c++ apple-backlight.cpp -o apple-backlight

then run:

Code:

$ sudo ./apple-backlight <OPTIONS>

where <OPTIONS> contains which interface to test (--nvidia should work) as well as --get or --set <VALUE>.

also, did you try to use the nvidia_bl driver? please note: installing both drivers is no problem, but mbp_nvidia_bl will not auto-load anymore (which doesn't matter since it doesn't support your machine anyway).

ciao,
Mario

**pliz** · January 5th, 2011

Hi Mario, I have exactly the same problem as described in te current thread after 10.10 install on macbook pro 6.2:
sudo modprobe mbp_nvidia_bl
FATAL: Error inserting mbp_nvidia_bl (/lib/modules/2.6.35-24-generic/kernel/drivers/video/backlight/mbp_nvidia_bl.ko): No such device
and also with
nvclock -Sf 10
Unable to shadow the video bios
It seems your card isn't officialy supported in NVClock yet.
The reason can be that your card is too new.
If you want to try it anyhow [DANGEROUS], use the option -f to force the setting(s).
NVClock will then assume your card is a 'normal', it might be dangerous on other cards.
Also please email the author the pci_id of the card for further investigation.
[Get that value using the -i option].

your tool does the job correctly. Is it integrated into ubuntu already, so the keyboard brightness control works? How do I merge it into my installation (everything is up to date now)?
Thanks!