From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Walleij <linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH 1/3] mtd: create a partition type device tree binding
Date: Sat, 14 Nov 2015 11:46:59 +0100
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To: Brian Norris <computersforpeace-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, "devicetree-spec-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <devicetree-spec-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, "linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" <linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>, "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" <linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>, "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>, Liviu Dudau <Liviu.Dudau-5wv7dgnIgG8@public.gmane.org>, =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= <zajec5-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Hauke Mehrtens <hauke-5/S+JYg5SzeELgA04lAiVw@public.gmane.org>, Michal Suchanek <hramrach-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

On Fri, Nov 13, 2015 at 11:00 PM, Brian Norris
<computersforpeace-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:

(...)
>  (2) we should define a comptible property for the hard-coded
>  partitioning case (e.g., compatible = "partitions")
(...)
> If we went with option (2), then ofpart.c could just check only for
> 'compatible = "partitions"' (or similar), and if not found bail out.

So this "hard-coded partitioning case" the case is where all partitions
are defined in the device tree as described in
Documentation/devicetree/bindings/mtd/partition.txt ?

Or is it a way to indicate that this array
static const char * const part_probe_types_def[] = {
        "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL };
in physmap_of.c should be used?

Sorry if I don't fully follow, I'm a bit stupid when it comes to the MTD
helicopter  view of the situation.... :(

> I think option (2) makes more sense. But it would require an update to
> the binding and code for 4.4, since [1] was only introduced during this
> release cycle.

Does that mean all old device trees that specify no compatible
string all of a sudden stop working? We can't break the DT ABI, so I
guess not.

A bit confused here, I can't really see what I should do with the patch...

Yours,
Linus Walleij