[PATCH RFC 4/6] net: rfkill: gpio: add device tree support

[heikki.krogerus@linux.intel.com (Heikki Krogerus)]

Hi,

On Sat, Jan 18, 2014 at 12:11:56AM +0100, Linus Walleij wrote:
> On Fri, Jan 17, 2014 at 6:43 PM, Chen-Yu Tsai <wens@csie.org> wrote:
> > On Sat, Jan 18, 2014 at 12:47 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> 
> >>> +- NAME_shutdown-gpios  : GPIO phandle to shutdown control
> >>> +                         (phandle must be the second)
> >>> +- NAME_reset-gpios     : GPIO phandle to reset control
> >>> +
> >>> +NAME must match the rfkill-name property. NAME_shutdown-gpios or
> >>> +NAME_reset-gpios, or both, must be defined.
> >>> +
> >>
> >> I don't understand this part. Why do you include the name in the
> >> gpios property, rather than just hardcoding the property strings
> >> to "shutdown-gpios" and "reset-gpios"?
> >
> > This quirk is a result of how gpiod_get_index implements device tree
> > lookup.
> 
> Why can't it just have a single property "gpios", where the first
> element is the reset GPIO and the second is the shutdown GPIO?
> 
> rfkill-gpio does this:
> 
> gpio = devm_gpiod_get_index(&pdev->dev, rfkill->reset_name, 0);
> gpio = devm_gpiod_get_index(&pdev->dev, rfkill->shutdown_name, 1);
> 
> The passed con ID name parameter is only there for the device
> tree case it seems. (ACPI ignores it.) So what about you just
> don't pass it at all and patch it to do like this instead:
> 
> gpio = devm_gpiod_get_index(&pdev->dev, NULL, 0);
> gpio = devm_gpiod_get_index(&pdev->dev, NULL, 1);
> 
> Heikki, are you OK with this change?

Yes, definitely. That is much cleaner.

Thanks,

-- 
heikki