gpio: pl061: use chained_irq_* functions in irq handler

Use chained_irq_enter/exit helper functions instead of direct pointer
accesses. This is needed for generic irq chip conversion.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Linus Walleij <linus.ml.walleij@gmail.com>

drivers/gpio/gpio-pl061.c

@@ -23,6 +23,7 @@
 #include <linux/amba/bus.h>
 #include <linux/amba/pl061.h>
 #include <linux/slab.h>
+#include <asm/mach/irq.h>
 
 #define GPIODIR 0x400
 #define GPIOIS  0x404
@@ -211,8 +212,9 @@ static void pl061_irq_handler(unsigned irq, struct irq_desc *desc)
 	struct list_head *chip_list = irq_get_handler_data(irq);
 	struct list_head *ptr;
 	struct pl061_gpio *chip;
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
 
-	desc->irq_data.chip->irq_ack(&desc->irq_data);
+	chained_irq_enter(irqchip, desc);
 	list_for_each(ptr, chip_list) {
 		unsigned long pending;
 		int offset;
@@ -227,7 +229,7 @@ static void pl061_irq_handler(unsigned irq, struct irq_desc *desc)
 		for_each_set_bit(offset, &pending, PL061_GPIO_NR)
 			generic_handle_irq(pl061_to_irq(&chip->gc, offset));
 	}
-	desc->irq_data.chip->irq_unmask(&desc->irq_data);
+	chained_irq_exit(irqchip, desc);
 }
 
 static int pl061_probe(struct amba_device *dev, const struct amba_id *id)