Help answer threads with 0 replies.
Go Back > Forums > Linux Forums > Linux - Laptop and Netbook
User Name
Linux - Laptop and Netbook Having a problem installing or configuring Linux on your laptop? Need help running Linux on your netbook? This forum is for you. This forum is for any topics relating to Linux and either traditional laptops or netbooks (such as the Asus EEE PC, Everex CloudBook or MSI Wind).


  Search this Thread
Old 07-14-2009, 04:52 PM   #1
Registered: Apr 2007
Distribution: suse 10.2
Posts: 324

Rep: Reputation: 31
Question Changes to Panasonic hotkey driver invalidate the acpi handler scripts

Hi everyone,

I'm working with a Panasonic CF-18 toughbook, upgrading from a 2.6.22 to a 2.6.30 kernel, and of course certain things need to be reworked. I've figured out most problems I had in the transition, but I can't get certain acpi events to trigger properly.

Some Panasonic laptops used to require a pcc hotkey driver module found here in order for certain buttons to work, such as backlight dimming and brightening, volume buttons, etc. For them to work, the hotkey handler scripts were necessary to echo values to specific files in the /proc/acpi/pcc directory. Unfortunately this module couldn't be built for kernels after approximately 2.6.22 due to too many changes.

With recent kernel versions 2.6.29 and 2.6.30, the Panasonic hotkey driver was included in the mainline kernel under drivers/platform/x86/panasonic-laptop.c

Unfortunately this current driver doesn't use the /proc directory for its interfaces. Instead it creates the interfaces in /sys/class/backlight/panasonic

(I am only really interested in getting backlight brightness to work as I work in both indoor and outdoor environments, everything else can be accessed through the software)

I can't seem to properly modify the acpi handler scripts found on the same site as the original pcc drivers to work with the new driver. I can manually echo values between 0 (dim) and 255 (bright) to /sys/class/backlight/panasonic/brightness to change the brightness, but I can't seem to get a script to do the same for the two buttons on the laptop.

The specific interfaces inside /sys/class/backlight/panasonic/ are as follows:
actual_brightness = a read-only file that displays the current brightness value
bl_power = a read-write file that I assume controls the power to the backlight. Value currently is at 0 with screen on.
brightness = a read-write file where brightness values can be written to.
max_brightness = a read-only file that reminds us all that the max value for brightness cannot exceed 255. Its value is permanantly at 255.

If anyone can help rework the handler script for the backlight, or make a new one from scratch, I and many other Toughbook usere would surely appreciate it! Thanks in advance!

Old 07-25-2009, 05:47 PM   #2
Registered: Apr 2007
Distribution: suse 10.2
Posts: 324

Original Poster
Rep: Reputation: 31
I am respectfully bumping this topic as I've not had any suggestions. If anyone can help me with writing apropriate acpi scripts for this, I'd be very grateful.


acpi, hotkey, panasonic, toughbook

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Panasonic printer without linux driver, how to enable printing sasicherukole Linux - Newbie 1 06-29-2009 01:23 PM
Driver problem with Panasonic KXP 1150 Lord_Tenebrus Linux - Hardware 3 01-19-2006 09:47 AM
Aspire 1524, hotkey problems - can't install acerhk driver IglooGuy Linux - Laptop and Netbook 0 05-18-2005 08:38 AM
ACPI scripts ? dimgr Linux - Laptop and Netbook 2 01-04-2005 07:56 PM
ATI 7200 mobility on Panasonic toughbook CF-48x driver? Lleb_KCir Linux - Hardware 12 11-27-2004 04:42 PM > Forums > Linux Forums > Linux - Laptop and Netbook

All times are GMT -5. The time now is 11:50 PM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration