ARM: OMAP3+: PRM: register interrupt information from DT

Allow the PRM interrupt information to be picked up from device tree.
OMAP3 may use legacy boot and needs to be compatible with old dtbs
(without interrupt populated), for these, we use the value which is
pre-populated.

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>

arch/arm/mach-omap2/prm3xxx.c

@@ -17,6 +17,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/irq.h>
+#include <linux/of_irq.h>
 
 #include "soc.h"
 #include "common.h"
@@ -649,13 +650,30 @@ int __init omap3xxx_prm_init(void)
 	return prm_register(&omap3xxx_prm_ll_data);
 }
 
+static struct of_device_id omap3_prm_dt_match_table[] = {
+	{ .compatible = "ti,omap3-prm" },
+	{ }
+};
+
 static int omap3xxx_prm_late_init(void)
 {
 	int ret;
 
 	if (!(prm_features & PRM_HAS_IO_WAKEUP))
 		return 0;
 
+	if (of_have_populated_dt()) {
+		struct device_node *np;
+		int irq_num;
+
+		np = of_find_matching_node(NULL, omap3_prm_dt_match_table);
+		if (np) {
+			irq_num = of_irq_get(np, 0);
+			if (irq_num >= 0)
+				omap3_prcm_irq_setup.irq = irq_num;
+		}
+	}
+
 	omap3xxx_prm_enable_io_wakeup();
 	ret = omap_prcm_register_chain_handler(&omap3_prcm_irq_setup);
 	if (!ret)