gpio: vx855: use gpiochip data pointer

This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-vx855.c

@@ -96,7 +96,7 @@ static inline u_int32_t gpio_o_bit(int i)
 static int vx855gpio_direction_input(struct gpio_chip *gpio,
 				     unsigned int nr)
 {
-	struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio);
+	struct vx855_gpio *vg = gpiochip_get_data(gpio);
 	unsigned long flags;
 	u_int32_t reg_out;
 
@@ -120,7 +120,7 @@ static int vx855gpio_direction_input(struct gpio_chip *gpio,
 
 static int vx855gpio_get(struct gpio_chip *gpio, unsigned int nr)
 {
-	struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio);
+	struct vx855_gpio *vg = gpiochip_get_data(gpio);
 	u_int32_t reg_in;
 	int ret = 0;
 
@@ -146,7 +146,7 @@ static int vx855gpio_get(struct gpio_chip *gpio, unsigned int nr)
 static void vx855gpio_set(struct gpio_chip *gpio, unsigned int nr,
 			  int val)
 {
-	struct vx855_gpio *vg = container_of(gpio, struct vx855_gpio, gpio);
+	struct vx855_gpio *vg = gpiochip_get_data(gpio);
 	unsigned long flags;
 	u_int32_t reg_out;
 
@@ -259,7 +259,7 @@ static int vx855gpio_probe(struct platform_device *pdev)
 
 	vx855gpio_gpio_setup(vg);
 
-	return gpiochip_add(&vg->gpio);
+	return gpiochip_add_data(&vg->gpio, vg);
 }
 
 static int vx855gpio_remove(struct platform_device *pdev)