From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Holler <holler@ahsoftware.de>
Subject: Re: [PATCH v4 1/2] gpio/omap: don't create an IRQ mapping for every
 GPIO on DT
Date: Mon, 29 Jul 2013 13:33:45 +0200
Message-ID: <51F65319.7000901@ahsoftware.de>
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To: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Cc: Javier Martinez Canillas <martinez.javier@gmail.com>, Linus Walleij <linus.walleij@linaro.org>, "Shilimkar, Santosh" <santosh.shilimkar@ti.com>, ext Tony Lindgren <tony@atomide.com>, Grant Likely <grant.likely@secretlab.ca>, Kevin Hilman <khilman@linaro.org>, Jon Hunter <jgchunter@gmail.com>, Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>, Enric Balletbo Serra <eballetbo@gmail.com>, Linux-OMAP <linux-omap@vger.kernel.org>, Florian Vaussard <florian.vaussard@epfl.ch>, Aaro Koskinen <aaro.koskinen@iki.fi>, "Krishnamoorthy, Balaji T" <balajitk@ti.com>

Am 29.07.2013 13:30, schrieb Alexander Holler:

>> So I think the driver has to be changed independently of the approach
>> for auto request GPIO used.
>
> Maybe, but that isn't much effort. I had done that in 3 minutes (ok,
> without the would be necessary #ifdef CONFIG_OF_GPIO). But you have a
> chicken and egg situation here, because you can't change drivers without
> the new patch and you can't introduce the new patch without changes to
> drivers.
>
> As I had mentioned before, another approach could be to map the irq when
> gpio_to_irq() is called. I think that would be downward compatible
> without the need for some changes in a dts.

Having send that, I had another idea: introduce a config option to 
enable/disable the new behaviour. That would make it possible to change 
drivers while not breaking compatibility, and when all are changed, the 
config option could go away.

Regards,

Alexander Holler