ARM: tegra: update GPIO chained IRQ handler to use entry/exit functions

This patch updates the Tegra gpio chained IRQ handler to use the chained
IRQ enter/exit functions in order to function correctly on primary
controllers with different methods of flow control.

This is required for the GIC to move to fasteoi interrupt handling.

Acked-by: Colin Cross <ccross@android.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm/mach-tegra/gpio.c b/arch/arm/mach-tegra/gpio.c
index 65a1aba..919d638 100644
--- a/arch/arm/mach-tegra/gpio.c
+++ b/arch/arm/mach-tegra/gpio.c
@@ -24,6 +24,8 @@
 #include <linux/io.h>
 #include <linux/gpio.h>
 
+#include <asm/mach/irq.h>
+
 #include <mach/iomap.h>
 #include <mach/suspend.h>
 
@@ -221,8 +223,9 @@
 	int port;
 	int pin;
 	int unmasked = 0;
+	struct irq_chip *chip = irq_desc_get_chip(desc);
 
-	desc->irq_data.chip->irq_ack(&desc->irq_data);
+	chained_irq_enter(chip, desc);
 
 	bank = irq_get_handler_data(irq);
 
@@ -241,7 +244,7 @@
 			 */
 			if (lvl & (0x100 << pin)) {
 				unmasked = 1;
-				desc->irq_data.chip->irq_unmask(&desc->irq_data);
+				chained_irq_exit(chip, desc);
 			}
 
 			generic_handle_irq(gpio_to_irq(gpio + pin));
@@ -249,7 +252,7 @@
 	}
 
 	if (!unmasked)
-		desc->irq_data.chip->irq_unmask(&desc->irq_data);
+		chained_irq_exit(chip, desc);
 
 }