of/device: Merge of_platform_bus_probe()

Merge common code between PowerPC and microblaze.  This patch merges
the code that scans the tree and registers devices.  The functions
merged are of_platform_bus_probe(), of_platform_bus_create(), and
of_platform_device_create().

This patch also move the of_default_bus_ids[] table out of a Microblaze
header file and makes it non-static.  The device ids table isn't merged
because powerpc and microblaze use different default data.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
CC: Michal Simek <monstr@monstr.eu>
CC: Grant Likely <grant.likely@secretlab.ca>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: microblaze-uclinux@itee.uq.edu.au
CC: linuxppc-dev@ozlabs.org

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 7dacc1e..d9c81e9 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -14,6 +14,7 @@
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/device.h>
+#include <linux/dma-mapping.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
 
@@ -396,3 +397,145 @@
 	driver_unregister(&drv->driver);
 }
 EXPORT_SYMBOL(of_unregister_driver);
+
+#if !defined(CONFIG_SPARC)
+/*
+ * The following routines scan a subtree and registers a device for
+ * each applicable node.
+ *
+ * Note: sparc doesn't use these routines because it has a different
+ * mechanism for creating devices from device tree nodes.
+ */
+
+/**
+ * of_platform_device_create - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @bus_id: name to assign device
+ * @parent: Linux device model parent device.
+ */
+struct of_device *of_platform_device_create(struct device_node *np,
+					    const char *bus_id,
+					    struct device *parent)
+{
+	struct of_device *dev;
+
+	dev = of_device_alloc(np, bus_id, parent);
+	if (!dev)
+		return NULL;
+
+	dev->archdata.dma_mask = 0xffffffffUL;
+	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+	dev->dev.bus = &of_platform_bus_type;
+
+	/* We do not fill the DMA ops for platform devices by default.
+	 * This is currently the responsibility of the platform code
+	 * to do such, possibly using a device notifier
+	 */
+
+	if (of_device_register(dev) != 0) {
+		of_device_free(dev);
+		return NULL;
+	}
+
+	return dev;
+}
+EXPORT_SYMBOL(of_platform_device_create);
+
+/**
+ * of_platform_bus_create - Create an OF device for a bus node and all its
+ * children. Optionally recursively instantiate matching busses.
+ * @bus: device node of the bus to instantiate
+ * @matches: match table, NULL to use the default, OF_NO_DEEP_PROBE to
+ * disallow recursive creation of child busses
+ */
+static int of_platform_bus_create(const struct device_node *bus,
+				  const struct of_device_id *matches,
+				  struct device *parent)
+{
+	struct device_node *child;
+	struct of_device *dev;
+	int rc = 0;
+
+	for_each_child_of_node(bus, child) {
+		pr_debug("   create child: %s\n", child->full_name);
+		dev = of_platform_device_create(child, NULL, parent);
+		if (dev == NULL)
+			rc = -ENOMEM;
+		else if (!of_match_node(matches, child))
+			continue;
+		if (rc == 0) {
+			pr_debug("   and sub busses\n");
+			rc = of_platform_bus_create(child, matches, &dev->dev);
+		}
+		if (rc) {
+			of_node_put(child);
+			break;
+		}
+	}
+	return rc;
+}
+
+/**
+ * of_platform_bus_probe - Probe the device-tree for platform busses
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table, NULL to use the default
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * Note that children of the provided root are not instantiated as devices
+ * unless the specified root itself matches the bus list and is not NULL.
+ */
+int of_platform_bus_probe(struct device_node *root,
+			  const struct of_device_id *matches,
+			  struct device *parent)
+{
+	struct device_node *child;
+	struct of_device *dev;
+	int rc = 0;
+
+	if (matches == NULL)
+		matches = of_default_bus_ids;
+	if (matches == OF_NO_DEEP_PROBE)
+		return -EINVAL;
+	if (root == NULL)
+		root = of_find_node_by_path("/");
+	else
+		of_node_get(root);
+
+	pr_debug("of_platform_bus_probe()\n");
+	pr_debug(" starting at: %s\n", root->full_name);
+
+	/* Do a self check of bus type, if there's a match, create
+	 * children
+	 */
+	if (of_match_node(matches, root)) {
+		pr_debug(" root match, create all sub devices\n");
+		dev = of_platform_device_create(root, NULL, parent);
+		if (dev == NULL) {
+			rc = -ENOMEM;
+			goto bail;
+		}
+		pr_debug(" create all sub busses\n");
+		rc = of_platform_bus_create(root, matches, &dev->dev);
+		goto bail;
+	}
+	for_each_child_of_node(root, child) {
+		if (!of_match_node(matches, child))
+			continue;
+
+		pr_debug("  match: %s\n", child->full_name);
+		dev = of_platform_device_create(child, NULL, parent);
+		if (dev == NULL)
+			rc = -ENOMEM;
+		else
+			rc = of_platform_bus_create(child, matches, &dev->dev);
+		if (rc) {
+			of_node_put(child);
+			break;
+		}
+	}
+ bail:
+	of_node_put(root);
+	return rc;
+}
+EXPORT_SYMBOL(of_platform_bus_probe);
+#endif /* !CONFIG_SPARC */