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!