From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: I2C with bus muxes From: Ben Warren To: Kumar Gala In-Reply-To: <61F75343-B9B9-4349-A463-E39C7532A378@kernel.crashing.org> References: <1153408592.19682.39.camel@saruman.qstreams.net> <61F75343-B9B9-4349-A463-E39C7532A378@kernel.crashing.org> Content-Type: multipart/alternative; boundary="=-WrCtDF2BI0tQ3K4wSVsy" Date: Thu, 20 Jul 2006 15:01:37 -0400 Message-Id: <1153422097.19682.84.camel@saruman.qstreams.net> Mime-Version: 1.0 Cc: Linuxppc-embedded@ozlabs.org Reply-To: bwarren@qstreams.com List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --=-WrCtDF2BI0tQ3K4wSVsy Content-Type: text/plain Content-Transfer-Encoding: 7bit Way cool! Thanks a lot. I'll try it out when my hardware comes in... regards, Ben On Thu, 2006-07-20 at 13:51 -0500, Kumar Gala wrote: > On Jul 20, 2006, at 10:16 AM, Ben Warren wrote: > > > Hello, > > > > Has anyone implemented devices like the Philips PCA954x I2C bus muxes > > under the /sysfs device model? I have some optical transponders on my > > board that through the wisdom of some committee all have the same > > fixed > > I2C address. To get around this, we put them behind muxes, creating > > 'virtual' I2C busses. I imagine this could be modeled something like > > the USB hub model, but that's just a first stab. > > I'm pretty sure I submitted a set of patches for this upstream. > However there was some desire to hold off until some other changes. > > http://marc.theaimsgroup.com/?l=linux-kernel&m=114376108231285&w=2 > http://marc.theaimsgroup.com/?t=114316214100001&r=1&w=2 > > - kumar > > --=-WrCtDF2BI0tQ3K4wSVsy Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit Way cool!  Thanks a lot.  I'll try it out when my hardware comes in...

regards,
Ben

On Thu, 2006-07-20 at 13:51 -0500, Kumar Gala wrote: 
On Jul 20, 2006, at 10:16 AM, Ben Warren wrote:

> Hello,
>
> Has anyone implemented devices like the Philips PCA954x I2C bus muxes
> under the /sysfs device model?  I have some optical transponders on my
> board that through the wisdom of some committee all have the same  
> fixed
> I2C address.  To get around this, we put them behind muxes, creating
> 'virtual' I2C busses.  I imagine this could be modeled something like
> the USB hub model, but that's just a first stab.

I'm pretty sure I submitted a set of patches for this upstream.   
However there was some desire to hold off until some other changes.

http://marc.theaimsgroup.com/?l=linux-kernel&m=114376108231285&w=2
http://marc.theaimsgroup.com/?t=114316214100001&r=1&w=2

- kumar
--=-WrCtDF2BI0tQ3K4wSVsy--