gpio: regmap: Always set gpio_chip get_direction

If you only have reg_dat_base set, then it is input-only; if you only
have reg_set_base set, then it is output-only. Thus, we can always set
gpio_chip get_direction to gpio_regmap_get_direction and return
GPIO_LINE_DIRECTION_IN/GPIO_LINE_DIRECTION_OUT given the respective
register base addresses configuration.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Michael Walle <michael@walle.cc>
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-regmap.c

@@ -111,6 +111,11 @@ static int gpio_regmap_get_direction(struct gpio_chip *chip,
 	unsigned int base, val, reg, mask;
 	int invert, ret;
 
+	if (gpio->reg_dat_base && !gpio->reg_set_base)
+		return GPIO_LINE_DIRECTION_IN;
+	if (gpio->reg_set_base && !gpio->reg_dat_base)
+		return GPIO_LINE_DIRECTION_OUT;
+
 	if (gpio->reg_dir_out_base) {
 		base = gpio_regmap_addr(gpio->reg_dir_out_base);
 		invert = 0;
@@ -265,8 +270,8 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 	else if (gpio->reg_set_base)
 		chip->set = gpio_regmap_set;
 
+	chip->get_direction = gpio_regmap_get_direction;
 	if (gpio->reg_dir_in_base || gpio->reg_dir_out_base) {
-		chip->get_direction = gpio_regmap_get_direction;
 		chip->direction_input = gpio_regmap_direction_input;
 		chip->direction_output = gpio_regmap_direction_output;
 	}