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Date: Wed, 3 Sep 2014 17:37:07 +0200
From: Johan Hovold <johan@kernel.org>
To: Octavian Purdila <octavian.purdila@intel.com>
Cc: Johan Hovold <johan@kernel.org>, Lee Jones <lee.jones@linaro.org>,
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        Daniel Baluta <daniel.baluta@intel.com>,
        Laurentiu Palcu <laurentiu.palcu@intel.com>
Subject: Re: [PATCH v2 1/3] mfd: add support for Diolan DLN-2 devices
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On Wed, Sep 03, 2014 at 04:39:48PM +0300, Octavian Purdila wrote:
> On Tue, Sep 2, 2014 at 6:23 PM, Johan Hovold <johan@kernel.org> wrote:

> > That should be possible using the regmap bus read and write operations.
> 
> I took a closer look on the regmap bus read/write operations and I
> think they are not fit for what we need in the driver. The driver uses
> a request/response model which, IMHO, does not fit well with a
> register read/write API. Yes, maybe we can emulate it, but why do
> that?
> 
> >> (Also creating a regmap class for a particular device seems over
> >> engineering since nobody else is going to use it)
> >
> > Possibly, but it would allow subdrivers to be implemented using a
> > standard interface and also provide register caching for free.
> 
> Using a standard interface is nice, but I think that using the right
> interface type is more important. This hardware does not use registers
> but a messages to communicate with the OS.

You might be right, and as I mentioned, I haven't looked that closely at
the protocol yet. I'll take a look at your updated I/O interface and how
you use it.

Johan