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Date: Tue, 30 Oct 2007 13:38:50 -0600
From: "Grant Likely" <grant.likely@secretlab.ca>
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To: "Yoder Stuart-B08248" <stuart.yoder@freescale.com>
Subject: Re: RFC: replace device_type with new "class" property?
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On 10/30/07, Yoder Stuart-B08248 <stuart.yoder@freescale.com> wrote:
> Another good reason for device_type-- it helps
> distinguish between two similar classes of devices.
> Both "open-pic" and "isa-pic" look very similar but
> have different encodings of their interrupt cells.
> Without a device_type it may be difficult or impossible
> to distinguish them unless the "name" and
> "compatible" are luckily clear enough.

I don't think you want to go down that path.  If your compatible list
does not uniquely describe what the device is (followed by a list of
devices it is compatible with); then it is not specific enough.  It's
fine for a device driver to go looking at other properties to get more
details; but drivers should primarily bind on the compatible list.

In other words; device_type and/or class are a coarser grained
description of the device than the compatible list.  If you match on
compatible; why would there be any need at all to look at 'name',
'device_type' or the proposed 'class' properties?

Cheers,
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely@secretlab.ca
(403) 399-0195