gpio: max730x: 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().

Cc: Roland Stigge <stigge@antcom.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-max730x.c

@@ -50,7 +50,7 @@
 
 static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
 {
-	struct max7301 *ts = container_of(chip, struct max7301, chip);
+	struct max7301 *ts = gpiochip_get_data(chip);
 	u8 *config;
 	u8 offset_bits, pin_config;
 	int ret;
@@ -92,7 +92,7 @@ static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
 static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
 				    int value)
 {
-	struct max7301 *ts = container_of(chip, struct max7301, chip);
+	struct max7301 *ts = gpiochip_get_data(chip);
 	u8 *config;
 	u8 offset_bits;
 	int ret;
@@ -120,7 +120,7 @@ static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
 
 static int max7301_get(struct gpio_chip *chip, unsigned offset)
 {
-	struct max7301 *ts = container_of(chip, struct max7301, chip);
+	struct max7301 *ts = gpiochip_get_data(chip);
 	int config, level = -EINVAL;
 
 	/* First 4 pins are unused in the controller */
@@ -148,7 +148,7 @@ static int max7301_get(struct gpio_chip *chip, unsigned offset)
 
 static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-	struct max7301 *ts = container_of(chip, struct max7301, chip);
+	struct max7301 *ts = gpiochip_get_data(chip);
 
 	/* First 4 pins are unused in the controller */
 	offset += 4;
@@ -213,7 +213,7 @@ int __max730x_probe(struct max7301 *ts)
 		}
 	}
 
-	ret = gpiochip_add(&ts->chip);
+	ret = gpiochip_add_data(&ts->chip, ts);
 	if (ret)
 		goto exit_destroy;