diff --git a/drivers/tty/serial/serial_mctrl_gpio.h b/drivers/tty/serial/serial_mctrl_gpio.h
index b7d3cca48ede..1b2ff503b2c2 100644
--- a/drivers/tty/serial/serial_mctrl_gpio.h
+++ b/drivers/tty/serial/serial_mctrl_gpio.h
@@ -114,19 +114,19 @@ static inline
 struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
 				      enum mctrl_gpio_idx gidx)
 {
-	return ERR_PTR(-ENOSYS);
+	return NULL;
 }
 
 static inline
 struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
 {
-	return ERR_PTR(-ENOSYS);
+	return NULL;
 }
 
 static inline
 struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
 {
-	return ERR_PTR(-ENOSYS);
+	return NULL;
 }
 
 static inline