From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [PATCH 09/10] xen: arm: Drop
 device_tree_node_compatible
Date: Wed, 18 Jun 2014 16:20:02 +0100
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To: Julien Grall <julien.grall@linaro.org>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Naresh Bhat <naresh.bhat@linaro.org>, tim@xen.org, xen-devel@lists.xen.org, Roy Franz <roy.franz@linaro.org>, Fu Wei <fu.wei@linaro.org>
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On Wed, 2014-06-18 at 15:57 +0100, Julien Grall wrote:
> On 06/18/2014 03:47 PM, Ian Campbell wrote:
> > On Wed, 2014-06-18 at 15:43 +0100, Stefano Stabellini wrote:
> >> On Mon, 16 Jun 2014, Ian Campbell wrote:
> >>> Instead use fdt_node_check_compatible from libfdt.
> >>
> >> Unfortunately the two functions are not equivalent:
> >> fdt_node_check_compatible uses memcmp while device_tree_node_compatible
> >> uses strcasecmp that ignores cases.
> > 
> > I hadn't spotted this.
> > 
> > They can't both be spec complaint I think. I expect
> > fdt_node_check_compatible (from libfdt) is more likely to be the one
> > which is correct.
> 
> In dt_device_is_compatible we use strcasecmp as Linux does.
> 
> For Linux, it looks like the use a less restrictive way in generic code
> (i.e strcasecmp) and more restrictive on SPARC (i.e strcmp)
> 
> I can't find anything in the spec to say which one is better. But I
> think we want to stay compatible with Linux we have to keep
> device_tree_node_compatible and use it in place of
> fdt_node_check_compatible.

Urk, what a mess.

This patch was pretty tangential to the series, I'll just drop it.

Ian.


> We could also modify the latter function for our convenience.
> 
> Regards.
>