[PATCH][OF] Add of_device_is_available function

[Benjamin Herrenschmidt]

On Tue, 2008-02-26 at 13:34 -0800, David Miller wrote:
> From: Paul Mackerras <paulus at samba.org>
> Date: Tue, 26 Feb 2008 20:04:12 +1100
> 
> > It would probably be good to defend against the possibility that the
> > property isn't null-terminated (for example if its length is zero).
> 
> FWIW, when I pull in the device tree on sparc I eliminate any need for
> those kinds of checks by putting a '\0' at the end of every property
> blob.
> 
> I copied a lot of this code from you guys, so it wouldn't surprise
> me if ppc does this too.  :-)

I doubt we do that. Properties that contain things like ranges, or "reg"
properties are expected to be of a size that is a multiple of
#size-cells/#address-cells and I'm not sure that won't break things here
or there if they suddenly get one more byte..

Or do you mean you/we are appending that-without- changing the length
field ?

Ben.