SHMobile Compatibility String Inconsistencies

On Thu, Aug 22, 2013 at 12:43:14PM +0200, Laurent Pinchart wrote:

Hi Simon,

On Thursday 22 August 2013 14:46:40 Simon Horman wrote:

quoted

Hi Laurent, Hi Guennadi, Hi All,

Olof has brought to my attention that there is some inconsistency in the way
that compatibility strings for SHMobile are named and he has asked us to
clean things up for v3.12.

Looking through arch/arm/boot/dts/ I see that we have:

1. {gpio,pfc}-r8aXXXX and;
2. r8aXXXX-sdhi

The inconsistency that Olof has asked us to resolve is that we should either
use r8aXXXX- or -r8aXXXX. Not both.

It seems to me that neither option is inherently better than the other
so we should just choose the path of least resistance to make things
consistent.

Laurent, Guennadi, do you have any opinions on if it would be easier to
change the GPIO and PFC compatibility strings; or to change the SDHI
compatibility strings?

I don't think either of the options would be significantly more complex than 
the other one.

quoted

Ideally I would like you to come to some sort of consensus and send patches.

Shouldn't the consensus be ARM-wide instead of SH-wide ? Quoting one of my 
replies to Stephen Warren from another mail thread:

My understanding from Olof is that it is fine to just make
an SH-mobile-wide decision.

quoted

In the bindings I've seen, it's more typical for the compatible value to
be ${vendor},${soc}-${unit} than ${vendor},${unit}-${soc}. I guess I
don't know how common one format or the other is though.

I'm personally fine with both. However, when using a version number, the 
format is ${vendor},${unit}-${version}. As we don't have an IP core version 
number we use the SoC name instead, so ${vendor},${unit}-${soc} would make 
sense. We should probably decide on one of the two alternatives and document 
it. 

Ok, so on the one hand ${vendor},${soc}-${unit} is more common.
But on the other hand because we use ${soc} in place of ${version} it
seems there are cases where it would make sense for use to use
${vendor},${unit}-${soc}.

I believe that the second hand trumps the first and we should go with
${vendor},${unit}-${soc} on SH-mobile as that should over all our
use-cases.

Does that sound reasonable to you?