More on hotplug issue w/HAL

[Matthew Mastracci]

> Ok, the conclusion seemed to be that i2c_adapter class devices bridges
> between the PCI and i2c bus (much like PCI devices that USB
> controllers), so we should probably change how HAL handles i2c_adaptors
> to it corresponds to how other other bridge devices are handled.
> 
> Basically, since they are class devices they should just merge
> properties into the PCI device (the silicon) they belong to. This would
> amount to adding the capability i2c_adapter to that device and setting
> the property i2c_adaptor.name to the name we get from sysfs.
> 
> This is completely analogue to what the properties merged into the PCI
> device being a USB controller, see

Ahh...  okay.  This makes much more sense to me.  

>  http://freedesktop.org/~david/hal-pci-usb.png
> 
> note that this PCI device got the capability serial_controller.usb. This
> would conclude handling of i2c_adapter devices. You would probably put
> this in files linux_class_i2c_adaptor.[ch]

Sure- I started writing an I2C class driver but I wasn't sure if it was
necessary.  I can see now where this class driver fits into sysfs.

> In addition, we should check for i2c devices (which are physical
> devices) and attach them to the proper parent i2c_adaptor. Do you have
> any i2c devices in your sysfs tree? I don't have any :-/ (need to find
> my tv tuner card). This could go in existing files linux_i2c.[ch].

I have a number of them.  You probably have one or two on your
motherboard.  In fact, your SMBus AMD756 adapter is an I2C adapter.  You
just need to modprobe a few I2C devices and they should appear
underneath.  Unfortunately, there's no way to know what you have unless
you just modprobe them all, one by one.

I would try the w83781d driver to start.  If not, just modprobe all of
the .ko's in /lib/modules/__/drivers/i2c/chips until you get a few in
your tree.  :)

> Seems doable?

Yep!  Thanks (and to gregkh too) for clearing up my sysfs confusion.  I
think this should go in pretty smoothly.

-- 
Matthew Mastracci <matt at aclaro.com>