OMAP: omap_device: make all devices a child of a new parent device

In order to help differentiate omap_devices from normal
platform_devices, make them all a parent of a new common parent
device.

Then, in order to determine if a platform_device is also an
omap_device, checking the parent is all that is needed.

Users of this feature are the runtime PM core for OMAP, where we need
to know if a device being passed in is an omap_device or not in order
to know whether to call the omap_device API with it.

In addition, all omap_devices will now show up under /sys/devices/omap
instead of /sys/devices/platform
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/plat-omap/include/plat/omap_device.h

@@ -36,6 +36,8 @@
 
 #include <plat/omap_hwmod.h>
 
+extern struct device omap_device_parent;
+
 /* omap_device._state values */
 #define OMAP_DEVICE_STATE_UNKNOWN	0
 #define OMAP_DEVICE_STATE_ENABLED	1

arch/arm/plat-omap/omap_device.c

@@ -465,6 +465,7 @@ int omap_device_register(struct omap_device *od)
 {
 	pr_debug("omap_device: %s: registering\n", od->pdev.name);
 
+	od->pdev.dev.parent = &omap_device_parent;
 	return platform_device_register(&od->pdev);
 }
 
@@ -737,3 +738,14 @@ int omap_device_enable_clocks(struct omap_device *od)
 	/* XXX pass along return value here? */
 	return 0;
 }
+
+struct device omap_device_parent = {
+	.init_name	= "omap",
+	.parent         = &platform_bus,
+};
+
+static int __init omap_device_init(void)
+{
+	return device_register(&omap_device_parent);
+}
+core_initcall(omap_device_init);