gpio: wm831x: 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: patches@opensource.wolfsonmicro.com
Cc: Mark Brown <broonie@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-wm831x.c

@@ -30,14 +30,9 @@ struct wm831x_gpio {
 	struct gpio_chip gpio_chip;
 };
 
-static inline struct wm831x_gpio *to_wm831x_gpio(struct gpio_chip *chip)
-{
-	return container_of(chip, struct wm831x_gpio, gpio_chip);
-}
-
 static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int val = WM831X_GPN_DIR;
 
@@ -51,7 +46,7 @@ static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 
 static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int ret;
 
@@ -67,7 +62,7 @@ static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
 
 static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 
 	wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
@@ -77,7 +72,7 @@ static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 static int wm831x_gpio_direction_out(struct gpio_chip *chip,
 				     unsigned offset, int value)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int val = 0;
 	int ret;
@@ -99,7 +94,7 @@ static int wm831x_gpio_direction_out(struct gpio_chip *chip,
 
 static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 
 	return irq_create_mapping(wm831x->irq_domain,
@@ -109,7 +104,7 @@ static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
 				    unsigned debounce)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int reg = WM831X_GPIO1_CONTROL + offset;
 	int ret, fn;
@@ -140,7 +135,7 @@ static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
 #ifdef CONFIG_DEBUG_FS
 static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 {
-	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int i, tristated;
 
@@ -264,7 +259,7 @@ static int wm831x_gpio_probe(struct platform_device *pdev)
 	else
 		wm831x_gpio->gpio_chip.base = -1;
 
-	ret = gpiochip_add(&wm831x_gpio->gpio_chip);
+	ret = gpiochip_add_data(&wm831x_gpio->gpio_chip, wm831x_gpio);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 		return ret;