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

From: Alexandre Courbot
Date: Tue Feb 11 2014 - 21:21:16 EST


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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