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Subject: Re: "cell-index" vs. "index" vs. no index in I2C device nodes
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Scott Wood <scottwood@freescale.com>
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Date: Fri, 06 Jun 2008 14:13:43 +1000
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Cc: linuxppc-dev@ozlabs.org, Stefan Roese <sr@denx.de>,
	Timur Tabi <timur@freescale.com>
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On Wed, 2008-06-04 at 10:43 -0500, Scott Wood wrote:
> > I just posted a patch for the FSL I2C driver to check for cell-index.  I'm under
> > the impression that cell-index is the standard for enumerating devices in the
> > device tree.
> 
> No, it's the standard for correlating devices with portions of a shared
> register block elsewhere.  Your use in the I2C node is merely a hack to
> deal with Linux wanting to deal with indices rather than pointers,
> combined with a lack of a decent way to look up a device struct from the
> device node.

Totally agreed. cell-index should -only- be about correlating a given
device in an ASIC with some shared register (an example coming to mind
is clock control registers with one bit per cell) etc...

For the rest, well, use aliases :-)

Ben.