[U-Boot-Users] Using a second I2C interface

Howard, Marc Marc.Howard at KLA-Tencor.com
Fri May 12 21:37:32 CEST 2006

> On May 12, 2006, at 9:36 AM, Ben Warren wrote:
> > Hello,
> >
> > The CPU I'm using (MPC8349) has two hardware I2C interfaces, and  
> > I'd like to access the second one in U-boot.  Implementing this  
> > looks easy to me, but I don't want to reinvent the wheel if it's  
> > already been done elsewhere.  Has anyone done this?  If not, I'll  
> > follow up with a proposal.
> Depending on what you want to do, you can cheat and just change the  
> pointer to the 2nd interface.  If you want something more full  
> featured up to the command level then I think some discussion would  
> be required on how the commands should work for specifying which  
> controller to use.
> - kumar

OK, just as a suggestion how about an optional suffix on all the I2C
commands. Ex:

iprobe.2 -- discover valid I2C interfaces on controller #2.

imw.0 (or just imw) -- memory write to address on controller #0 (or the
only controller in most cases).

Seems like it wouldn't break anything to specify the controller this

Marc W. Howard

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