Recent Nvidia drivers are not able to control screen brightness on HP Elitebook Mobile Workstation

I have an EliteBook 8560w Mobile Workstation with a Quadro 1000m GPU.

On Ubuntu 12.04 LTS with 304.88 my system works as expected.
This is also true for 310.x versions, however, they have been removed from the official repositories (or it is just the jockey driver manager too lazy to show them). Unfortunately, with 313.x and 319.x, I can not control screen brightness (FN-key operations are recognized).

I thought that the new 331.x series would solve the problem as it has the following line in the what’s new description: “Added a new NV-CONTROL attribute, NV_CTRL_BACKLIGHT_BRIGHTNESS, for controlling backlight brightness.”. However, I have red forums on the net and it turned out, that with Ubuntu 13.10 and the very latest nvidia 331.x drivers, brightness control still does not work.

Sad background story: I have replaced my AMD GPU based HP notebook to this because of bad GPU driver support (AMD Legacy card). I thought to myself that this enterprise grade notebook equipped with this serious GPU would have no such problem. And when I bought this notebook 6 months ago, I was so satisfied that everything just worked.
However, now I’m desperately waiting for a fix for this problem. I can not use OpenSuSe or Fedora as they only have newer drivers in the repositories, and the 304.x drivers (which are the legacy branch for 6/7 series) do not work. I can still use the computer with Ubuntu 12.04 LTS/304.88 drivers until 2017 April. However, the software is becoming outdated, and Steam always notifies me that I should update my drivers.

My opinion: I think that Nvidia should make sure that at least the Quadro workhorses are supported well, even under Linux. I really hope that there will be a fix for this, and I will have the chance to move on with the next LTS Ubuntu release, which is 14.04 LTS, so the next one. I hope that my purchase will last longer than only one Ubuntu distribution.

I think that my problem is a duplicate of this: https://devtalk.nvidia.com/default/topic/539462/-nvidia-319-12-brightness-controls-not-working-on-laptop-ubuntu-13-03-/

Question: Is this problem acknowledged? And if so, can we be sure that a fix will come in the near future?

New launchpad bugreport made:
https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1281019

I would like to encourage EVERYBODY who has the same problems to subscribe to that bugreport and update it with your information.

Maybe we can encourage Nvidia to put some effort in this bug which affects many users.

Thanks in advance!

I’ve found the solution. You’ve said that FN Keys are being noticed. Which is GREAT.
Let’s start with getting the ACPI Keys. Open the terminal. Type “acpi_listen”
Press FN+F5 and FN+F6
You should see something like “video/brightness BRTN 00000087 00000000” and “video/brightness BRTUP 00000086 00000000”
Now minimize the terminal for now. Go to /etc/acpi you should see “events” and “asus-keyboard-backlight.sh”
go into “events” and edit “asus-keyboard-backlight-down” as root.
You’ll see
“event=” Something here
“action=/etc/acpi/asus-keyboard-backlight.sh down”
replace the part in event with the code in terminal “acpi_listen” FN+F5
for me it would be “event=video/brightnessdown BRTDN 00000087 00000000”

Do the same with “asus-keyboard-backlight-up” but instead of the key for FN+F5 its FN+F6
Save and close them both. Now go back to “acpi” folder. You’ll see “asus-keyboard-backlight.sh”
edit it.

Change KEYS_DIR= to “KEYS_DIR=/sys/class/backlight/nvidia_backlight” I think Intel would be
“KEYS_DIR=/sys/class/backlight/intel_backlight”

I’d suggest changing the number in “VAL=((VAL-1))" to "VAL=((VAL-5))”
and do the same for the other one “VAL=((VAL+1))" -> "VAL=((VAL+5))”

also on the bottom it should say “echo $VAL | tee $KEYS_DIR/brightness”

now… SAVE IT…
open the terminal… and type. “sudo /etc/init.d/acpid restart”

This solved my Brightness problem :D Hope it solves yours too!

If you got the FN+Brightness keys working. this i think it should. My grub file has not been touched or anything.
I am running Linux Mint 17.1 on Asus G75VW with NVIDIA 660M :D

Also Since youre not running on an Asus. You might have to look for something else in “etc/acpi/events”
Might be something like “hp-keyboard-backlight-down” But it should work. As long as you have the acpi keys and all that.