Re: [PATCH] gpiolib: Add gpio_detect, gpio_debounce and gpio_alt_func features to GPIOLIB

[Florian Fainelli <florian@openwrt.org>]

Le Monday 15 June 2009 13:19:16 Alek Du, vous avez écrit :
> On Mon, 15 Jun 2009 18:02:53 +0800
>
> Mark Brown <broonie@opensource.wolfsonmicro.com> wrote:
> > On Mon, Jun 15, 2009 at 10:50:23AM +0100, Ben Dooks wrote:
> > > On Mon, Jun 15, 2009 at 05:15:02PM +0800, Alek Du wrote:
> > > > * gpio_alt_func is to set pin as alternative function or GPIO.
> > >
> > > gpio_alt_func is feature creep, I don't really belive this is the
> > > best place to put it as it will be difficult to actually make this
> > > generic for all gpio platforms.
> >
> > Since the proposed API just passes a value through to the driver for the
> > GPIO chip it looks generic enough - each chip can define whatever set of
> > constants it likes.  I'd expect a large proportion of driver specific
> > APIs would end up just the same.
> >
> > Given the number of manufacturers that don't use a separate term like
> > the PXA MFP for the alternative functions of their GPIOs it makes sense
> > to have a gpiolib API for this.  Without one you end up having each
> > driver needing to add its own API, and since the pins are just referred
> > to as GPIOs in the documentation the API will have that in the name and
> > look like it ought to be connected with gpiolib.
>
> Mark,
> Thanks for the comments. I do believe that API would benefit some GPIO
> device drivers. I'm preparing a GPIO driver for one Intel IOH that has GPIO
> block needs that API.

This is indeed useful, RB532 in the MIPS tree also has an alternate function 
setting feature.