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

From: Alexandre Courbot
Date: Wed Jul 30 2014 - 23:44:10 EST

On Mon, Jul 28, 2014 at 7:30 PM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
> 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.

Thanks! Unfortunately it is still not in -next due to a build error...

> 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?

I have such a file locally - I'm not sure if checking it into the
kernel tree is relevant though. Sounds more like the task of a wiki
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at