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Subject: Re: checking status semantics with compatible functions
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Grant Likely <grant.likely@secretlab.ca>
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Date: Tue, 05 Apr 2011 21:59:36 +1000
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On Wed, 2011-03-30 at 08:31 -0600, Grant Likely wrote:
> Yes, of_device_is_available() should be checked, but it should not be
> added directly to of_device_is_compatible().  I'm okay with adding
> a helper variant that does the of_device_is_compatible() check.
> 
> In that particular case, I'd also suggest using
> for_each_matching_node().

Agreed. A device might be unavailable due to how FW configured the
machine, but made later on available by the kernel, that shouldn't
impact the interface compatibility test.

Cheers,
Ben.