Handle the GPIOD_OPEN_DRAIN & GPIOD_OPEN_SOURCE flags to emulate open drain and open source by setting the GPIO line as input depending on the requested value.
The behaviour is taken from the Linux gpiolib.
Signed-off-by: Neil Armstrong narmstrong@baylibre.com --- drivers/gpio/gpio-uclass.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 757ab7106e..d3cea11f76 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -526,6 +526,21 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value)
if (desc->flags & GPIOD_ACTIVE_LOW) value = !value; + + /* + * Emulate open drain by not actively driving the line high or + * Emulate open source by not actively driving the line low + */ + if ((desc->flags & GPIOD_OPEN_DRAIN && value) || + (desc->flags & GPIOD_OPEN_SOURCE && !value)) + return gpio_get_ops(desc->dev)->direction_input(desc->dev, + desc->offset); + else if (desc->flags & GPIOD_OPEN_DRAIN || + desc->flags & GPIOD_OPEN_SOURCE) + return gpio_get_ops(desc->dev)->direction_output(desc->dev, + desc->offset, + value); + gpio_get_ops(desc->dev)->set_value(desc->dev, desc->offset, value); return 0; }