of/irq: Move irq_of_parse_and_map() to common code

Merge common code between PowerPC and Microblaze.  SPARC implements
irq_of_parse_and_map(), but the implementation is different, so it
does not use this code.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>

diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
new file mode 100644
index 0000000..0e37c05
--- /dev/null
+++ b/include/linux/of_irq.h
@@ -0,0 +1,41 @@
+#ifndef __OF_IRQ_H
+#define __OF_IRQ_H
+
+#if defined(CONFIG_OF)
+struct of_irq;
+#include <linux/types.h>
+#include <linux/of.h>
+
+/*
+ * irq_of_parse_and_map() is used ba all OF enabled platforms; but SPARC
+ * implements it differently.  However, the prototype is the same for all,
+ * so declare it here regardless of the CONFIG_OF_IRQ setting.
+ */
+extern unsigned int irq_of_parse_and_map(struct device_node *node, int index);
+
+#if defined(CONFIG_OF_IRQ)
+/**
+ * of_irq - container for device_node/irq_specifier pair for an irq controller
+ * @controller: pointer to interrupt controller device tree node
+ * @size: size of interrupt specifier
+ * @specifier: array of cells @size long specifing the specific interrupt
+ *
+ * This structure is returned when an interrupt is mapped. The controller
+ * field needs to be put() after use
+ */
+#define OF_MAX_IRQ_SPEC		4 /* We handle specifiers of at most 4 cells */
+struct of_irq {
+	struct device_node *controller; /* Interrupt controller node */
+	u32 size; /* Specifier size */
+	u32 specifier[OF_MAX_IRQ_SPEC]; /* Specifier copy */
+};
+
+extern int of_irq_map_one(struct device_node *device, int index,
+			  struct of_irq *out_irq);
+extern unsigned int irq_create_of_mapping(struct device_node *controller,
+					  const u32 *intspec,
+					  unsigned int intsize);
+
+#endif /* CONFIG_OF_IRQ */
+#endif /* CONFIG_OF */
+#endif /* __OF_IRQ_H */