gpio: max77620: Implement .get_direction() callback

Add support for reporting the current GPIO line direction by implementing
the .get_direction() callback for the MAX77620 GPIO controller.

Signed-off-by: Diogo Ivo <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-max77620.c

···
 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
+static int max77620_gpio_get_dir(struct gpio_chip *gc, unsigned int offset)
+{
+	struct max77620_gpio *mgpio = gpiochip_get_data(gc);
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(mgpio->rmap, GPIO_REG_ADDR(offset), &val);
+	if (ret < 0) {
+		dev_err(mgpio->dev, "CNFG_GPIOx read failed: %d\n", ret);
+		return ret;
+	}
+
+	if (val & MAX77620_CNFG_GPIO_DIR_MASK)
+		return GPIO_LINE_DIRECTION_IN;
+	else
+		return GPIO_LINE_DIRECTION_OUT;
+}
+
 static int max77620_gpio_dir_input(struct gpio_chip *gc, unsigned int offset)
 {
 	struct max77620_gpio *mgpio = gpiochip_get_data(gc);
···
 
 	mgpio->gpio_chip.label = pdev->name;
 	mgpio->gpio_chip.parent = pdev->dev.parent;
+	mgpio->gpio_chip.get_direction = max77620_gpio_get_dir;
 	mgpio->gpio_chip.direction_input = max77620_gpio_dir_input;
 	mgpio->gpio_chip.get = max77620_gpio_get;
 	mgpio->gpio_chip.direction_output = max77620_gpio_dir_output;