Thinkpad-ACPI Brightness Not Working 2.6.26

[DarkDexter]

I just compiled 2.6.26 kernel on Debian for my Thinkpad T61p. I've flashed the BIOS and tinkered with various things but I cannot get the brightness keys to work. They worked fine in 2.6.25 but there is some features I need in 2.6.26 that are keeping me from rolling back.

Anyone one else have this problem on the new kernel? Anyone have a solution? Specs below...

Kernel: 2.6.26
Debian Testing
NVIDIA Proprietry Driver

[DarkDexter]

Update:
I tried recompiling with Thinkpad-acpi ACPI_VIDEO off in hopes it would fix the problem. No dice. acpi_listen still reports only Brightness up and no brightness down button, it was doing this before with ACPI_VIDEO in either way.

Any one else having similar issues?

[DarkDexter]

Update:
Under 2.6.25 brightness is working as usual and running acpi_listen and pressing the brightness up and down generates no signals.

Under 2.6.26 bightness is still not working and pressing brighness up generates a signal while pressing down does not.

It would appear that 25 is preforming the right behavior. Here is the output of dmesg | grep think on 25:

Linux version 2.6.25-dexmix-thinkpad (root@DexLap-ThnkPd) (gcc version 4.2.3 (Debian 4.2.3-3)) #1 SMP Thu Apr 17 14:38:27 PDT 2008
thinkpad_acpi: ThinkPad ACPI Extras v0.19
thinkpad_acpi: http://ibm-acpi.sf.net/
thinkpad_acpi: ThinkPad BIOS 7LETB9WW (2.19 ), EC 7KHT24WW-1.08
thinkpad_acpi: Lenovo ThinkPad T61p
thinkpad_acpi: radio switch found; radios are enabled
thinkpad_acpi: standard ACPI backlight interface available, not loading native one...


and for 26:

Linux version 2.6.26-dexmix-thinkpad (root@DexLap-ThnkPd) (gcc version 4.3.1 (Debian 4.3.1-2) ) #1 SMP Thu Jul 17 21:38:49 PDT 2008
thinkpad_acpi: ThinkPad ACPI Extras v0.20
thinkpad_acpi: http://ibm-acpi.sf.net/
thinkpad_acpi: ThinkPad BIOS 7LETB9WW (2.19 ), EC 7KHT24WW-1.08
thinkpad_acpi: Lenovo ThinkPad T61p, model 6459CTO
thinkpad_acpi: radio switch found; radios are enabled
thinkpad_acpi: This ThinkPad has standard ACPI backlight brightness control, supported by the ACPI video driver
thinkpad_acpi: Disabling thinkpad-acpi brightness events by default...
Registered led device: tpacpi::thinklight
thinkpad_acpi: Lenovo BIOS switched to ACPI backlight control mode
thinkpad_acpi: standard ACPI backlight interface available, not loading native one...


Is there anyway to force 26 to behave like 25 or is this a deeper kernel bug? Any help, suggestions, or insight is highly appreciated!

[DarkDexter]

I'm starting to be convinced this is a bug in v0.20 of the thinkpad_ACPI. I'd like to submit a bug report but obviously cant use the handy reportbug in this case. What's a good formal way to submit a bug report for this so the maintainer doesn't want to kill me?

[ikke]

Cant the new bios be the source of the trouble ???

[MkIII_Supra]

What model of Thinkpad? I am having the same issue with my T61 and OpenSuSE 11.0.

[DarkDexter]

Sorry, I didn't notice I finally got some replies!

ikke: It wasn't working before or after the BIOS update, so I'm gonna consider it unrelated. When I rolled back to an older kernel it worked perfectly. So I'm assuming its a bug in the new kernel.

MkIII Supra: Thinkpad T61p. 2.5Ghz Core 2 Duo. 2GB of RAM. Nvidia Quatro Graphics. I've tried various versions of the nvidia drivers to no effect either so I'm still convince its a kernel bug.


I'm gonna be trying 2.6.26.2 today to see how it goes. Will post results.

[DarkDexter]

FIXED! The way the ACPI video works in 2.6.26 is really different so you need to add these two things to your .config

CONFIG_VIDEO_OUTPUT_CONTROL
CONFIG_ACPI_VIDEO


That will fix all the problems! Be sure to disable Thinkpad Video in the thinkpad_acpi section!

Details here: http://www.nabble.com/T61-Brightness-keys-with-2.6.26-not-working-(NVIDIA)-td18577619.html

[gamblor01]

Awesome. I am hoping IBM will approve a new work laptop for me in the near future. I just 'upgraded' from a T40 to a T42 recently, but both of them are pretty old. This one at least had a 1.6 GHz CPU (instead of 1.5) and a 5400 RPM hard drive (instead of 4200)! I really hate my 1024x768 resolution though.

If I can get IBM to approve to a T61p for me, I will definitely keep this in mind as I run Ubuntu on my work laptop!