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Date: Fri, 21 May 2010 06:23:12 -0700 (PDT)
From: David Brownell <david-b@pacbell.net>
Subject: Re: [PATCH 1/5] gpiolib: introduce set_debounce method
To: felipe.balbi@nokia.com
Cc: "Balbi Felipe \(Nokia-D/Helsinki\)" <felipe.balbi@nokia.com>,
       Mark Brown <broonie@opensource.wolfsonmicro.com>,
       Linux OMAP Mailing List <linux-omap@vger.kernel.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Tony Lindgren <tony@atomide.com>,
       Andrew Morton <akpm@linux-foundation.org>
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> > Not all GPIOs have hardware debounce though, so
> offering this
> > capability sort of begs the question of where/how to
> provide a software debounce mechanism too...
> 
> how about adding a flag for supported features and if that
> hardware doesn't support we simply return,

Presense of a debounce method would suffice when gpiolib is
in use (vs direct implementation of the API provided by gpiolib).


> or fallback to
> software emulation if chosen by the user. 

ISTR that if you look back to the original discussion about
GPIO debouncing, you will find such a software implementation;
and maybe such an integration ...