mfd: sm501: 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: Ben Dooks <ben@fluff.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/sm501.c

@@ -879,11 +879,6 @@ static int sm501_register_display(struct sm501_devdata *sm,
 
 #ifdef CONFIG_MFD_SM501_GPIO
 
-static inline struct sm501_gpio_chip *to_sm501_gpio(struct gpio_chip *gc)
-{
-	return container_of(gc, struct sm501_gpio_chip, gpio);
-}
-
 static inline struct sm501_devdata *sm501_gpio_to_dev(struct sm501_gpio *gpio)
 {
 	return container_of(gpio, struct sm501_devdata, gpio);
@@ -892,7 +887,7 @@ static inline struct sm501_devdata *sm501_gpio_to_dev(struct sm501_gpio *gpio)
 static int sm501_gpio_get(struct gpio_chip *chip, unsigned offset)
 
 {
-	struct sm501_gpio_chip *smgpio = to_sm501_gpio(chip);
+	struct sm501_gpio_chip *smgpio = gpiochip_get_data(chip);
 	unsigned long result;
 
 	result = smc501_readl(smgpio->regbase + SM501_GPIO_DATA_LOW);
@@ -923,7 +918,7 @@ static void sm501_gpio_ensure_gpio(struct sm501_gpio_chip *smchip,
 static void sm501_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 
 {
-	struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+	struct sm501_gpio_chip *smchip = gpiochip_get_data(chip);
 	struct sm501_gpio *smgpio = smchip->ourgpio;
 	unsigned long bit = 1 << offset;
 	void __iomem *regs = smchip->regbase;
@@ -948,7 +943,7 @@ static void sm501_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 
 static int sm501_gpio_input(struct gpio_chip *chip, unsigned offset)
 {
-	struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+	struct sm501_gpio_chip *smchip = gpiochip_get_data(chip);
 	struct sm501_gpio *smgpio = smchip->ourgpio;
 	void __iomem *regs = smchip->regbase;
 	unsigned long bit = 1 << offset;
@@ -974,7 +969,7 @@ static int sm501_gpio_input(struct gpio_chip *chip, unsigned offset)
 static int sm501_gpio_output(struct gpio_chip *chip,
 			     unsigned offset, int value)
 {
-	struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+	struct sm501_gpio_chip *smchip = gpiochip_get_data(chip);
 	struct sm501_gpio *smgpio = smchip->ourgpio;
 	unsigned long bit = 1 << offset;
 	void __iomem *regs = smchip->regbase;
@@ -1039,7 +1034,7 @@ static int sm501_gpio_register_chip(struct sm501_devdata *sm,
 	gchip->base   = base;
 	chip->ourgpio = gpio;
 
-	return gpiochip_add(gchip);
+	return gpiochip_add_data(gchip, chip);
 }
 
 static int sm501_register_gpio(struct sm501_devdata *sm)