Re: keyboard backlight working on PowerBook5,6?
On Tue, 31 May 2005 21:32:35 -0400
Barry Hawkins <email@example.com> wrote:
first for the files:
You have an 1.67GHz PowerBook G4 and keyboard illumination wont work
You had an 15" 1.25GHz PowerBook G4 with working keyboard light.
The code in pbbuttonsd controlling the keyboard illumination is rather old
and might be outdated. I have only an G3 Powerbook at hand so that I
can't do any tests myself.
Lets analyze the environment on your machine:
1. Are appropriate I2C modules loaded? According what I have read here
I would say: Yes.
2. Do all needed devices exist? /dev/i2c-0 ... i2c-n? Check this even if you used
udev or devfs.
So lets analyze if the code in pbbuttonsd should still work or if it
needs some refreshment.
1. Pbbuttonsd uses it's own i2c-dev.h and don't use the kernel version.
This is so because as I built in keyboard light support, I2C was at its
beginning and the kernel files prevent pbbuttonsd from compiling. Most
of the I2C programs uses this include file that is still part of the
- New kernel versions might have problems with this old file?
- Could you exchange it with the current kernel files and try it again?
2. Pbbuttonsd looks for the I2C Device 0x42, which is not defined in the
new kernel include files: ioctl (fd, I2C_SLAVE, 0x42)
- Did the address change in new kernel versions? Don't know how to check
3. If the above ioctl call was successful, four bytes would be read from
the device. If we receive exactly four bytes, the device is identified.
This worked in the past.
- Maybe the driver or device behaviour changed and we get more or less
than four bytes now?
You see, if we can't find a simple configuration error it could become
As I already told you I can't do any tests on this issue myself because
I don't have the right hardware. So it would be nice if someone of you
with some programming skills could do the research. I will assist as
good as I can.
The other way would be you send me your machine and I will do it. :-)