Re: [PATCH v2 1/2] of/gpio: Define OF_GPIO_OPEN_DRAIN and OF_GPIO_OPEN_SOURCE flags.

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On Wed, Feb 12, 2014 at 4:49 AM, David Daney <ddaney.cavm@xxxxxxxxx> wrote:
> From: David Daney <david.daney@xxxxxxxxxx>
>
> When we have a GPIO pin connected to an open-drain network, we want a
> standard way of specifying this in the device tree.  So we choose bit
> 1 of the flag field to indicate open drain.
>
> A typical use case would be something like:
>
>         enum of_gpio_flags f;
>         .
>         .
>         .
>         reset_gpio = of_get_named_gpio_flags(node, "reset", 0, &f);
>         .
>         .
>         .
>         ret = gpio_request_one(reset_gpio,
>                 (f & OF_GPIO_OPEN_DRAIN) ? GPIOF_OPEN_DRAIN : 0,
>                  "reset");
>         .
>         .
>         .
>         gpio_direction_output(reset_gpio, 1);
>         gpio_set_value(reset_gpio, 0);
>         msleep(20);
>         gpio_set_value(reset_gpio, 1);
>         .
>         .
>         .
>
> Since the same arguments hold for open-source configurations, add a
> definition for OF_GPIO_OPEN_SOURCE as well.
>
> Signed-off-by: David Daney <david.daney@xxxxxxxxxx>

Reviewed-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
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