gpio: altera: 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: Tien Hock Loh <thloh@altera.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c
index 84a20af..2aeaebd 100644
--- a/drivers/gpio/gpio-altera.c
+++ b/drivers/gpio/gpio-altera.c
@@ -42,11 +42,6 @@
 	int mapped_irq;
 };
 
-static struct altera_gpio_chip *to_altera(struct gpio_chip *gc)
-{
-	return container_of(gc, struct altera_gpio_chip, mmchip.gc);
-}
-
 static void altera_gpio_irq_unmask(struct irq_data *d)
 {
 	struct altera_gpio_chip *altera_gc;
@@ -54,7 +49,7 @@
 	unsigned long flags;
 	u32 intmask;
 
-	altera_gc = to_altera(irq_data_get_irq_chip_data(d));
+	altera_gc = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 	mm_gc = &altera_gc->mmchip;
 
 	spin_lock_irqsave(&altera_gc->gpio_lock, flags);
@@ -72,7 +67,7 @@
 	unsigned long flags;
 	u32 intmask;
 
-	altera_gc = to_altera(irq_data_get_irq_chip_data(d));
+	altera_gc = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 	mm_gc = &altera_gc->mmchip;
 
 	spin_lock_irqsave(&altera_gc->gpio_lock, flags);
@@ -92,7 +87,7 @@
 {
 	struct altera_gpio_chip *altera_gc;
 
-	altera_gc = to_altera(irq_data_get_irq_chip_data(d));
+	altera_gc = gpiochip_get_data(irq_data_get_irq_chip_data(d));
 
 	if (type == IRQ_TYPE_NONE)
 		return 0;
@@ -145,7 +140,7 @@
 	unsigned int data_reg;
 
 	mm_gc = to_of_mm_gpio_chip(gc);
-	chip = container_of(mm_gc, struct altera_gpio_chip, mmchip);
+	chip = gpiochip_get_data(gc);
 
 	spin_lock_irqsave(&chip->gpio_lock, flags);
 	data_reg = readl(mm_gc->regs + ALTERA_GPIO_DATA);
@@ -165,7 +160,7 @@
 	unsigned int gpio_ddr;
 
 	mm_gc = to_of_mm_gpio_chip(gc);
-	chip = container_of(mm_gc, struct altera_gpio_chip, mmchip);
+	chip = gpiochip_get_data(gc);
 
 	spin_lock_irqsave(&chip->gpio_lock, flags);
 	/* Set pin as input, assumes software controlled IP */
@@ -186,7 +181,7 @@
 	unsigned int data_reg, gpio_ddr;
 
 	mm_gc = to_of_mm_gpio_chip(gc);
-	chip = container_of(mm_gc, struct altera_gpio_chip, mmchip);
+	chip = gpiochip_get_data(gc);
 
 	spin_lock_irqsave(&chip->gpio_lock, flags);
 	/* Sets the GPIO value */
@@ -215,7 +210,7 @@
 	unsigned long status;
 	int i;
 
-	altera_gc = to_altera(irq_desc_get_handler_data(desc));
+	altera_gc = gpiochip_get_data(irq_desc_get_handler_data(desc));
 	chip = irq_desc_get_chip(desc);
 	mm_gc = &altera_gc->mmchip;
 	irqdomain = altera_gc->mmchip.gc.irqdomain;
@@ -244,7 +239,7 @@
 	unsigned long status;
 	int i;
 
-	altera_gc = to_altera(irq_desc_get_handler_data(desc));
+	altera_gc = gpiochip_get_data(irq_desc_get_handler_data(desc));
 	chip = irq_desc_get_chip(desc);
 	mm_gc = &altera_gc->mmchip;
 	irqdomain = altera_gc->mmchip.gc.irqdomain;
@@ -292,7 +287,7 @@
 	altera_gc->mmchip.gc.owner		= THIS_MODULE;
 	altera_gc->mmchip.gc.parent		= &pdev->dev;
 
-	ret = of_mm_gpiochip_add(node, &altera_gc->mmchip);
+	ret = of_mm_gpiochip_add_data(node, &altera_gc->mmchip, altera_gc);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n");
 		return ret;