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Date: Thu, 5 Jun 2008 13:56:25 -0500
From: Josh Boyer <jwboyer@linux.vnet.ibm.com>
To: "Grant Likely" <grant.likely@secretlab.ca>
Subject: Re: "cell-index" vs. "index" vs. no index in I2C device nodes
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Cc: Scott Wood <scottwood@freescale.com>, linuxppc-dev@ozlabs.org,
	Stefan Roese <sr@denx.de>, Timur Tabi <timur@freescale.com>
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On Thu, 5 Jun 2008 12:46:39 -0600
"Grant Likely" <grant.likely@secretlab.ca> wrote:

> > (And I'm talking about I2C, not DMA.  I don't care about DMA because
> > this conversation will go off into the weeds if we start talking about
> > cell-index and every possible device out there.)
> 
> I need to disagree here.  Behavior should never be dependent on device
> tree order.  It should be absolutely fine for devices to be probed in
> a different order and different bus ids to be assigned.

Meh.  I'll begrudgingly agree.

> In Timur's case, it is absolutely appropriate to use cell-index and/or
> a phandle to make sure it gets the correct DMA registers (which is
> what cell-index is intended to solve).  It is not appropriate to
> depend on that same number to also be the logical i2c bus number.

Hence "index" would be a better fit for the latter then, yes?

josh