pinctrl: meson: implement the gpio_chip get_direction callback

Implement the get_direction callback so we read the direction from the
actual GPIO controller register. This is recommended by the gpio_chip
kernel doc.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20200417183349.1283092-2-martin.blumenstingl@googlemail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/meson/pinctrl-meson.c

@@ -549,6 +549,18 @@ static const struct pinconf_ops meson_pinconf_ops = {
 	.is_generic		= true,
 };
 
+static int meson_gpio_get_direction(struct gpio_chip *chip, unsigned gpio)
+{
+	struct meson_pinctrl *pc = gpiochip_get_data(chip);
+	int ret;
+
+	ret = meson_pinconf_get_output(pc, gpio);
+	if (ret < 0)
+		return ret;
+
+	return ret ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
 static int meson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 {
 	return meson_pinconf_set_output(gpiochip_get_data(chip), gpio, false);
@@ -591,6 +603,7 @@ static int meson_gpiolib_register(struct meson_pinctrl *pc)
 	pc->chip.parent = pc->dev;
 	pc->chip.request = gpiochip_generic_request;
 	pc->chip.free = gpiochip_generic_free;
+	pc->chip.get_direction = meson_gpio_get_direction;
 	pc->chip.direction_input = meson_gpio_direction_input;
 	pc->chip.direction_output = meson_gpio_direction_output;
 	pc->chip.get = meson_gpio_get;