Subject: Re: SMBus implementation
To: Nicolas Joly <>
From: Jared D. McNeill <>
List: tech-kern
Date: 10/31/2005 18:02:38
On Mon, 2005-10-31 at 22:44 +0100, Nicolas Joly wrote:
> On Tue, Oct 25, 2005 at 08:07:01PM -0300, Jared D. McNeill wrote:
> > So I was bored, and decided to whip up some SMBus support code. Feedback
> > would be great.
> > 
> > What's there:
> > 	FreeBSD-compatible /dev/smb* devices.
> > 	Support for the VIA VT8235 SMBus controller (on PCI-ISA bridge).
> > What's not:
> > 	No ability to attach hw drivers to the smbus device.
> > 	Maybe tie it in a bit tighter with the i2c stuff?
> > 
> > If you're feeling dangerous, the code is available here:
> >
> I wonder if SMBus detection code can be shared with viapm(4).
> The VT82C686A Power Management Controller, and probably others,
> includes a similar SMBus interface controller.

Yeah, that's the plan. The current state of viapcib is that it doesn't
quite work right (on my hardware, at least), and I haven't been able to
figure out why yet. Reads from all addresses look the same to me; it's
as if the 'set address' register is busted on the VT8235. I've been told
that this code works when copy/pasted to viapm.

Once I get the host controller code working here, then I'll split it out
so it can be shared.