Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h
index 3319535..78c3a31 100644
--- a/drivers/pinctrl/pinmux.h
+++ b/drivers/pinctrl/pinmux.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Internal interface between the core pin control system and the
  * pinmux portions
@@ -7,8 +8,6 @@
  * Based on bits of regulator core, gpio core and clk core
  *
  * Author: Linus Walleij <linus.walleij@linaro.org>
- *
- * License terms: GNU General Public License (GPL) version 2
  */
 #ifdef CONFIG_PINMUX
 
@@ -16,6 +15,8 @@
 
 int pinmux_validate_map(const struct pinctrl_map *map, int i);
 
+bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev, unsigned pin);
+
 int pinmux_request_gpio(struct pinctrl_dev *pctldev,
 			struct pinctrl_gpio_range *range,
 			unsigned pin, unsigned gpio);
@@ -43,6 +44,12 @@
 	return 0;
 }
 
+static inline bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev,
+					       unsigned pin)
+{
+	return true;
+}
+
 static inline int pinmux_request_gpio(struct pinctrl_dev *pctldev,
 			struct pinctrl_gpio_range *range,
 			unsigned pin, unsigned gpio)