From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
Subject: Re: [PATCH v3 2/8] reset: Add reset controller API
Date: Wed, 20 Feb 2013 10:10:27 -0700
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To: Philipp Zabel <p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Cc: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>, Fabio Estevam <fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org>, Mike Turquette <mturquette-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Sascha Hauer <s.hauer-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
List-Id: devicetree@vger.kernel.org

On 02/20/2013 04:04 AM, Philipp Zabel wrote:
> Hi,
> 
> Am Dienstag, den 19.02.2013, 14:39 -0700 schrieb Stephen Warren:
>> On 02/19/2013 04:35 AM, Philipp Zabel wrote:
>>> This adds a simple API for devices to request being reset
>>> by separate reset controller hardware and implements the
>>> reset signal device tree binding.

>>> +# reset controllers early, since gpu drivers might rely on them to initialize
>>> +obj-$(CONFIG_RESET_CONTROLLER)	+= reset/
>>
>> That sounds odd now. Shouldn't -EPROBE_DEFERRED sort out any ordering
>> issues?
> 
> Even so, isn't it useful to avoid the -EPROBE_DEFERRED loop when we
> expect other drivers to depend on resources provided by the reset
> controller drivers, but not the other way around?

If this Makefile ordering is solely to reduce the number of times
-EPROBE_DEFERRED is returned, it's probably fine. I just want to make
sure that the ordering isn't required to ensure correctness.

It's quite possible that in general a reset controller driver depends on
clocks, GPIOs, ... from other nodes though, so I'm not sure quite how
much this will buy us in the general case.