gpio: sta2x11: 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: Alessandro Rubini <rubini@gnudd.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-sta2x11.c b/drivers/gpio/gpio-sta2x11.c
index af0be81..83af1cb 100644
--- a/drivers/gpio/gpio-sta2x11.c
+++ b/drivers/gpio/gpio-sta2x11.c
@@ -74,7 +74,7 @@
 
 static void gsta_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
 {
-	struct gsta_gpio *chip = container_of(gpio, struct gsta_gpio, gpio);
+	struct gsta_gpio *chip = gpiochip_get_data(gpio);
 	struct gsta_regs __iomem *regs = __regs(chip, nr);
 	u32 bit = __bit(nr);
 
@@ -86,7 +86,7 @@
 
 static int gsta_gpio_get(struct gpio_chip *gpio, unsigned nr)
 {
-	struct gsta_gpio *chip = container_of(gpio, struct gsta_gpio, gpio);
+	struct gsta_gpio *chip = gpiochip_get_data(gpio);
 	struct gsta_regs __iomem *regs = __regs(chip, nr);
 	u32 bit = __bit(nr);
 
@@ -96,7 +96,7 @@
 static int gsta_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
 				      int val)
 {
-	struct gsta_gpio *chip = container_of(gpio, struct gsta_gpio, gpio);
+	struct gsta_gpio *chip = gpiochip_get_data(gpio);
 	struct gsta_regs __iomem *regs = __regs(chip, nr);
 	u32 bit = __bit(nr);
 
@@ -111,7 +111,7 @@
 
 static int gsta_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
 {
-	struct gsta_gpio *chip = container_of(gpio, struct gsta_gpio, gpio);
+	struct gsta_gpio *chip = gpiochip_get_data(gpio);
 	struct gsta_regs __iomem *regs = __regs(chip, nr);
 	u32 bit = __bit(nr);
 
@@ -121,7 +121,7 @@
 
 static int gsta_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
 {
-	struct gsta_gpio *chip = container_of(gpio, struct gsta_gpio, gpio);
+	struct gsta_gpio *chip = gpiochip_get_data(gpio);
 	return chip->irq_base + offset;
 }
 
@@ -409,7 +409,7 @@
 		goto err_free_descs;
 	}
 
-	err = gpiochip_add(&chip->gpio);
+	err = gpiochip_add_data(&chip->gpio, chip);
 	if (err < 0) {
 		dev_err(&dev->dev, "sta2x11 gpio: Can't register (%i)\n",
 			-err);