diff options
| author | Neil Armstrong | 2020-05-05 10:43:17 +0200 |
|---|---|---|
| committer | Neil Armstrong | 2020-05-11 15:12:53 +0200 |
| commit | 47bd533e9dd0f967ff7b62f3edfd6c97131e1501 (patch) | |
| tree | 2454f95a2f6666d56fa3351f78fdad2cb435cda0 /drivers | |
| parent | 375d79cdbb6bdeaa9bc10dd34c3b22dd6838d4f3 (diff) | |
gpio: emulate open drain & open source in dm_gpio_set_value()
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>
Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpio/gpio-uclass.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 757ab7106ee..d3cea11f76e 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; } |