Subject: Re: RFC: new device types in the device tree (RE: [PATCH] powerpc: Add EDAC platform devices for 85xx)

From: David Gibson <[email-masked]>
Date: Wed, 2 May 2007 11:19:57 +1000

On Wed, May 02, 2007 at 02:34:45AM +0200, Segher Boessenkool wrote:
> >> "name" = "memory-controller"
> >> "compatible" = "fsl,85xx-memory-controller"
> >> (or a more specific 85xx model if the controller
> >> isn't identical across those chips)
> >> No "device_type" at all, since there is no binding
> >> for this kind of device.
> >
> > Is "no device_type" really the approach that should be
> > taken?
> 
> Yes.
> 
> > booting-without-of.txt currently reads:
> >
> >    Every node which actually represents an actual device
> >    (that is, a node which isn't only a virtual "container"
> >    for more nodes, like "/cpus" is) is also required to
> >    have a "device_type" property indicating the type of
> >    node
> 
> That is wrong, IMNSHO.

I tend to agree. Device drivers should generally be searching on the
"compatible" property, not "device_type".  Defining new device_type
values isn't really of any use to the kernel, so we should just avoid
it.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson