Re: [PATCHv2] Input: omap4-keypad: Add pinctrl support

From: Linus Walleij
Date: Tue Oct 23 2012 - 06:29:26 EST

On Tue, Oct 23, 2012 at 12:23 PM, Thomas Petazzoni
<thomas.petazzoni@xxxxxxxxxxxxxxxxxx> wrote:
> On Tue, 23 Oct 2012 13:03:33 +0300, Felipe Balbi wrote:
>> > But it appears that shmobile prefer to get all resources using
>> > bus notifiers.
>> >
>> > So we need to form some kind of consensus ... or live with
>> > the fact that different systems do it different ways. Which will
>> > explode the day we need to use a driver on two systems,
>> > each using the other approach :-)
>> I much prefer having drivers explicitly manage all their resources,
>> which would mean that pinctrl calls need to be done on probe() and, if
>> necessary, during suspend()/resume().
>> Using bus notifiers for that is quite a hack IMHO.
> Agreed. Just like drivers do their ioremap, request_irq and others,
> they should also request their pin resources using the pinctrl API.
> Hiding this behind a bus notifier is not nice.

So the biggest implementation of the notifier approach to resource
handling is the SH clock thing:

It's made to be generic but AFAICT only SH is using this.

So according to that paradigm most device resources should
be handled that way if I understand correctly the basic idea.

So let's get Rafael, Paul and Magnus in here to beat us up
a bit :-)

Linus Walleij
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