gpiolib: of: improve gpiolib-of support of pull up/down on expanders

When using GPIO expanders attached to I2C ports, their set_config function
needs to be passed a config setting which contains options to enable pull
up or pull down bias feature.  In order to set this config properly,
the gpio parser needs to handle GPIO_PULL_UP and GPIO_PULL_DOWN.

This patch enables the flags corresponding to GPIO_PULL_UP and
GPIO_PULL_DOWN.

Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index ccc449d..2c5dd13 100644 (file)
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -344,6 +344,12 @@ struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
        if (transitory)
                lflags |= GPIO_TRANSITORY;
 
+       if (flags & OF_GPIO_PULL_UP)
+               lflags |= GPIO_PULL_UP;
+
+       if (flags & OF_GPIO_PULL_DOWN)
+               lflags |= GPIO_PULL_DOWN;
+
        ret = gpiod_configure_flags(desc, propname, lflags, dflags);
        if (ret < 0) {
                gpiod_put(desc);
@@ -585,6 +591,10 @@ static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
                *lflags |= GPIO_ACTIVE_LOW;
        if (xlate_flags & OF_GPIO_TRANSITORY)
                *lflags |= GPIO_TRANSITORY;
+       if (xlate_flags & OF_GPIO_PULL_UP)
+               *lflags |= GPIO_PULL_UP;
+       if (xlate_flags & OF_GPIO_PULL_DOWN)
+               *lflags |= GPIO_PULL_DOWN;
 
        if (of_property_read_bool(np, "input"))
                *dflags |= GPIOD_IN;