Re: [PATCH] gpio: add flags argument to gpiod_get*() functions

From: Linus Walleij
Date: Mon Jul 28 2014 - 06:30:26 EST


On Fri, Jul 25, 2014 at 4:38 PM, Alexandre Courbot <acourbot@xxxxxxxxxx> wrote:

> The huge majority of GPIOs have their direction and initial value set
> right after being obtained by one of the gpiod_get() functions. The
> integer GPIO API had gpio_request_one() that took a convenience flags
> parameter allowing to specify an direction and value applied to the
> returned GPIO. This feature greatly simplifies client code and ensures
> errors are always handled properly.
>
> A similar feature has been requested for the gpiod API. Since setting
> the direction of a GPIO is so often the very next action done after
> obtaining its descriptor, we prefer to extend the existing functions
> instead of introducing new functions that would raise the
> number of gpiod getters to 16 (!).
>
> The drawback of this approach is that all gpiod clients need to be
> updated. To limit the pain, temporary macros are introduced that allow
> gpiod_get*() to be called with or without the extra flags argument. They
> will be removed once all consumer code has been updated.
>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> ---
> This dude can be applied harmlessly to the GPIO tree - then I will go
> after every gpiod user to update the calls to gpiod_get*() before
> removing the macros in consumer.h.

OK I trust you. Patch applied with Broonie's review tag.

Just so we don't forget how we should move forward: Alex what do
you think about adding a drivers/gpio/TODO.TXT file outlining the
overall plan of the gpiod refactoring and clean-up work?

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/