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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: Discussion on SOC device tree bindings
Date: Mon, 15 Jan 2007 16:42:18 +0100
To: Sascha Hauer <s.hauer@pengutronix.de>
Cc: linuxppc-dev Development <linuxppc-dev@ozlabs.org>,
	Sven Luther <sven@genesi-usa.com>
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> How about always specifying the exact name and only the exact name
> in the device tree, i.e. mpc5200-fec on mpc5200, mpc5200b-fec on
> mpc5200b and so on.

No :-)

> This way the driver can decide whether or not it's
> compatible to a device

It already can.

> and we can be sure not to overlook any
> incompatibilities. We could even decide in later kernel versions that
> two devices are too incompatible and split the driver into two.

You can already; say you have a driver that will only work
on 5200b, is will match on that, and the "plain" 5200 driver
won't get a chance to grab the device.  You have to match
for the most specific first, of course.

> There may be incompatibilities between 5200 and 5200b which we simply 
> did
> not discover yet.

If that is so, than such a 5200b-specific driver can be
created (possibly just as some special cases in the
existing 5200 driver).

Listing something in the "compatible" property doesn't mean
the device is 100% compatible, just that it's mostly compatible.
Earlier entries in there are "more compatible" ;-)


Segher