---
 arch/avr32/mach-at32ap/pio.c |   73 ++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 72 insertions(+), 1 deletion(-)

Index: linux-2.6.18-avr32/arch/avr32/mach-at32ap/pio.c
===================================================================
--- linux-2.6.18-avr32.orig/arch/avr32/mach-at32ap/pio.c	2006-11-29 18:17:15.000000000 +0100
+++ linux-2.6.18-avr32/arch/avr32/mach-at32ap/pio.c	2006-11-30 11:50:27.000000000 +0100
@@ -11,6 +11,7 @@
 #include <linux/clk.h>
 #include <linux/debugfs.h>
 #include <linux/fs.h>
+#include <linux/irq.h>
 #include <linux/platform_device.h>
 
 #include <asm/gpio.h>
@@ -709,20 +710,90 @@ err_class_create:
 late_initcall(pio_init_dev);
 #endif /* CONFIG_PIO_DEV */
 
+/* Interrupt controller implementation */
+static void pio_mask_irq(unsigned int irq)
+{
+	struct pio_device *pio = get_irq_chip_data(irq);
+
+	pio_writel(pio, IDR, 1 << (irq & 0x1f));
+}
+
+static void pio_unmask_irq(unsigned int irq)
+{
+	struct pio_device *pio = get_irq_chip_data(irq);
+
+	pio_writel(pio, IER, 1 << (irq & 0x1f));
+}
+
+static int pio_set_irq_type(unsigned int irq, unsigned int flow_type)
+{
+	if (flow_type != IRQ_TYPE_NONE && flow_type != IRQ_TYPE_EDGE_BOTH)
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct irq_chip pio_irq_chip = {
+	.name		= "pio",
+	.mask		= pio_mask_irq,
+	.unmask		= pio_unmask_irq,
+	.set_type	= pio_set_irq_type,
+};
+
+static void demux_pio_irq(unsigned int irq, struct irq_desc *desc,
+			  struct pt_regs *regs)
+{
+	struct pio_device *pio = desc->handler_data;
+	struct irq_desc *ext_desc;
+	u32 status, pending;
+	unsigned int ext_irq;
+	unsigned int i;
+
+	status = pio_readl(pio, ISR);
+	pending = status & pio_readl(pio, IMR);
+
+	while (pending) {
+		i = fls(pending) - 1;
+		pending &= ~(1 << i);
+
+		ext_irq = gpio_to_irq(32 * pio_id(pio) + i);
+		ext_desc = irq_desc + ext_irq;
+		ext_desc->handle_irq(ext_irq, ext_desc, regs);
+	}
+}
+
 static int __init pio_probe(struct platform_device *pdev)
 {
 	struct pio_device *pio = NULL;
+	unsigned int i;
+	int int_irq, ext_irq;
 
 	BUG_ON(pdev->id >= MAX_NR_PIO_DEVICES);
 	pio = &pio_dev[pdev->id];
 	BUG_ON(!pio->regs);
 
-	/* TODO: Interrupts */
+	/* Set up interrupts */
+	pio_writel(pio, IDR, ~0UL);
+	pio_readl(pio, ISR);
+
+	ext_irq = gpio_to_irq(32 * pdev->id);
+	for (i = 0; i < 32; i++, ext_irq++) {
+		set_irq_chip_and_handler(ext_irq, &pio_irq_chip,
+					 handle_simple_irq);
+		set_irq_chip_data(ext_irq, pio);
+	}
+
+	int_irq = platform_get_irq(pdev, 0);
+	set_irq_chained_handler(int_irq, demux_pio_irq);
+	set_irq_data(int_irq, pio);
 
 	platform_set_drvdata(pdev, pio);
 
 	printk(KERN_INFO "%s: Atmel Port Multiplexer at 0x%p (irq %d)\n",
 	       pio->name, pio->regs, platform_get_irq(pdev, 0));
+	printk(KERN_INFO
+	       "%s: Handling 32 external IRQs, starting with IRQ %d\n",
+	       pio->name, ext_irq - 32);
 
 	return 0;
 }