Geode SC1100 i2c bus

[M. Warner Losh]

In message: <200702040918.37825.freebsd-hackers at dino.sk>
            Milan Obuch <freebsd-hackers at dino.sk> writes:
: On Sunday 04 February 2007 01:21, perryh at pluto.rain.com wrote:
: > > > The ACB is at the same level than Uart, so I had a look at sio
: > > > source and got a big headache. I'm not really used to drivers
: > > > nor kernel programming stuff, that's why I need your help.
: > >
: > > Why do you compare ACB and UART? In FreeBSD, sio is serial i/o
: > > controller, not superIO, maybe you are confused... ACB and UART
: > > does not have much in common...
: >
: > As I read the OP, both the ACB and the serial are in the same chip
: > (the superIO), so it would seem reasonable to expect that the method
: > of accessing the device registers in the (currently unsupported) ACB
: > might be similar to the method of accessing the device registers in
: > the (supported) serial port.
: >
: 
: You are right from the point of view 'how to access registers'. But what OP 
: wrote could be understand another way, too - he tried to modify sio to create 
: acb driver, which would not achieve the correct results. There is i2c 
: infrastructure in FreeBSD, acb driver should fit into its place there and it 
: is not that easy - I tried to understand it, but nobody could/was willing 
: to/did not care to help me understand it.

I'm happy to help you understand it.

Warner