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Date: Wed, 24 Feb 2010 11:21:26 -0800
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 13/14] Regulators: wm8400 - cleanup platform driver data
 handling
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On Wed, Feb 24, 2010 at 07:14:03PM +0000, Mark Brown wrote:
> On Wed, Feb 24, 2010 at 11:02:34AM -0800, Dmitry Torokhov wrote:
> > On Wed, Feb 24, 2010 at 10:25:49AM +0000, Mark Brown wrote:
> 
> > > Nack due to this change - this change would make it impossible for
> > > callers to actually call the function.  Note that nothing including only
> > > wm8400.h even has a struct declaration, much less defniition, for struct
> > > wm8400.
> 
> > If you notice I added forward declaration of "struct wm8400" to wm8400.h
> > thus users can pass around pointer to the structure.
> 
> This doesn't help unless you also provide a way for users to obtain a
> struct wm8400.

Why would they need it? Only code that creates instances of wm8400 needs
to know the definition of the sturcture, the rest can simply pass the
pointer around.

I guess there is disconnect between us and I do not see any users of
wm8400_register_regulator() in linux-next... Is there another tree I
could peek at?

> 
> > I really think we should refrain from passing naked 'struct device *'
> > pointers as much as possible since it is error prone. Otherwise
> > wm8400_register_regulator has no way of ensuting that passed  'dev' is
> > indeed wm8400.
> 
> Right, there's no type safety here (and this whole method of registering
> regulators is fairly deprecated anyway in favour of just straight
> platform data) but really it doesn't buy us much - the users get exactly
> the struct device they need to use passed in to them, there's really
> very little chance for them to get confused about what they're talking
> about.

-- 
Dmitry
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