Re: [PATCH 1/3] cs5535-gpio: add AMD CS5535/CS5536 GPIO driver support

[Takashi Iwai <tiwai@suse.de>]

At Thu, 20 Aug 2009 12:40:02 -0400,
Andres Salomon wrote:
> 
> On Thu, 20 Aug 2009 17:21:20 +0200
> Takashi Iwai <tiwai@suse.de> wrote:
> 
> > At Tue, 18 Aug 2009 17:53:14 -0400,
> > Andres Salomon wrote:
> > > 
> > > 
> > > This creates a CS5535/CS5536 GPIO driver which uses a gpio_chip
> > > backend (allowing GPIO users to use the generic GPIO API if
> > > desired) while also allowing architecture-specific users directly
> > > (via the cs5535_gpio_* functions).
> > 
> > Will be any user of cs5535_gpio_*() expected?  If not, it'd be better
> > not to export stuff, IMO.
> > 
> 
> The olpc-dcon driver, for one.  If desired, I can remove the exports
> for now.

Ah, OK.  If this is going to be merged soonish, it should be fine
to have the exports from the beginning.


> > > Tested on an OLPC machine.  Some Leemotes also use CS5536 (with a
> > > mips cpu), which is why this is in drivers/gpio rather than
> > > arch/x86. Currently, it conflicts with older geode GPIO support;
> > > once MFGPT support is reworked to also be more generic, the older
> > > geode code will be removed.
> > 
> > .... or you can rewrite the old driver to use the functions above?
> > Then the ugly Kconfig check can be dropped, too.  (yeah that's an
> > answer to my own question above.)
> 
> I guess in theory I could.. 
> 
> 
> > 
> > BTW CONFIG_GPIO_CS5536 and CONFIG_CS5536_GPIO are so confusing... :)
> > 
> 
> Agreed.  I'd really like CONFIG_CS5535_GPIO to go away, but first there
> needs to be a replacement.  CONFIG_CS5535_GPIO will probably also need
> to be marked DEPRECATED for a while, too, since it's a
> userspace-visible change.  I can follow up w/ a patch for that once
> people are happy w/ this current set of patches.

Agreed.  Unless the compatible feature is given, some deprecation
period would be safer.


thanks,

Takashi