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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: New fsl device bindings file
Date: Sat, 5 Jul 2008 01:12:31 +0200
To: Matt Sealey <matt@genesi-usa.com>
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>> 	/* deprecated; */
>> 	device_type =3D "i2c";
>
> How about "deprecated but kept for compatibility with true Open=20
> Firmware
> implementations"?

Well, except a flat tree isn't compatible with OF at all here.
A "device_type" promises a certain interface; a flat tree doesn't
even have the "open" method.  =46rom the OF base spec:

	=93device_type=94 S

	Standard property name to specify the implemented interface.

	prop-encoded-array: Text string encoded with encode-string.

	Specifies the =93device type=94 of this package, thus implying a
	specific set of package class methods implemented by this
	package.

> Seriously, you can't have a binding for "OF" and then cut out that=20
> part of the
> standard at a whim.

Nothing is cut out.  There never was a device binding for device_type
i2c; creating one would be a considerable effort, and since flat tree
users wouldn't use it anyway, you can't be seriously suggesting they
should do this.

> It should be there (at least for those parts which are
> governed by a client interface API, like display, serial etc.

Huh?  Nothing in the client interface mentions display or serial
as far as I know.

> but cutting it off takes away all it's meaning,

So what?  There _is_ no "real" device interface, when a flat tree is
used.

> plus Linux implementations STILL keep searching
> that property along with "compatible",

That's a bug.


Segher