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Message-ID: <45EE373B.80606@iinet.net.au>
Date: Wed, 07 Mar 2007 14:53:31 +1100
From: Ben Nizette <ben.nizette@iinet.net.au>
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To: NZG <ngustavson@emacinc.com>
CC: Linux Kernel list <linux-kernel@vger.kernel.org>
Subject: Re: passing function pointers through platform devices?
References: <200703061246.29615.ngustavson@emacinc.com>
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NZG wrote:
> I'm developing an SPI- bus >MMC/SD block driver translation layer.
> As part of this layer the write protect and card detect lines need to be read.
> The method for determining the state of these lines will be board specific.
> 
> Is it appropriate to pass a function pointer through a platform device 
> (declared in the mach initialization) to implement card_available and 
> write_protect function calls?
> Or is there a cleaner way to do it?

Once the generic GPIO framework migrates upstream from -mm you should 
just pass the GPIO token from board-specific code and gpio_get_value() it.

--Ben.