[POWERPC] ibmebus: Add device creation and bus probing based on of_device

The devtree root is now searched for devices matching a built-in whitelist
during boot, so these devices appear on the bus from the beginning.  It is
still possible to manually add/remove devices to/from the bus by using the
probe/remove sysfs interface.  Also, when a device driver registers itself,
the devtree is matched against its matchlist.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 82 insertions, 18 deletions

diff --git a/arch/powerpc/kernel/ibmebus.c b/arch/powerpc/kernel/ibmebus.c
index af21306e2ef..d21658140b6 100644
--- a/arch/powerpc/kernel/ibmebus.c
+++ b/arch/powerpc/kernel/ibmebus.c
@@ -51,6 +51,13 @@ static struct device ibmebus_bus_device = { /* fake "parent" device */
 
 struct bus_type ibmebus_bus_type;
 
+/* These devices will automatically be added to the bus during init */
+static struct of_device_id builtin_matches[] = {
+        { .compatible = "IBM,lhca" },
+        { .compatible = "IBM,lhea" },
+        {},
+};
+
 static void *ibmebus_alloc_coherent(struct device *dev,
                                     size_t size,
                                     dma_addr_t *dma_handle,
@@ -125,6 +132,67 @@ static struct dma_mapping_ops ibmebus_dma_ops = {
         .dma_supported  = ibmebus_dma_supported,
 };
 
+static int ibmebus_match_path(struct device *dev, void *data)
+{
+        struct device_node *dn = to_of_device(dev)->node;
+        return (dn->full_name &&
+                (strcasecmp((char *)data, dn->full_name) == 0));
+}
+
+static int ibmebus_match_node(struct device *dev, void *data)
+{
+        return to_of_device(dev)->node == data;
+}
+
+static int ibmebus_create_device(struct device_node *dn)
+{
+        struct of_device *dev;
+        int ret;
+
+        dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
+        if (!dev)
+                return -ENOMEM;
+
+        dev->dev.bus = &ibmebus_bus_type;
+        dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
+
+        ret = of_device_register(dev);
+        if (ret) {
+                of_device_free(dev);
+                return ret;
+        }
+
+        return 0;
+}
+
+static int ibmebus_create_devices(const struct of_device_id *matches)
+{
+        struct device_node *root, *child;
+        int ret = 0;
+
+        root = of_find_node_by_path("/");
+
+        for (child = NULL; (child = of_get_next_child(root, child)); ) {
+                if (!of_match_node(matches, child))
+                        continue;
+
+                if (bus_find_device(&ibmebus_bus_type, NULL, child,
+                                    ibmebus_match_node))
+                        continue;
+
+                ret = ibmebus_create_device(child);
+                if (ret) {
+                        printk(KERN_ERR "%s: failed to create device (%i)",
+                               __FUNCTION__, ret);
+                        of_node_put(child);
+                        break;
+                }
+        }
+
+        of_node_put(root);
+        return ret;
+}
+
 int ibmebus_register_driver(struct ibmebus_driver *drv)
 {
         return 0;
@@ -173,18 +241,6 @@ static struct device_attribute ibmebus_dev_attrs[] = {
         __ATTR_NULL
 };
 
-static int ibmebus_match_path(struct device *dev, void *data)
-{
-        int rc;
-        struct device_node *dn =
-                of_node_get(to_ibmebus_dev(dev)->ofdev.node);
-
-        rc = (dn->full_name && (strcasecmp((char*)data, dn->full_name) == 0));
-
-        of_node_put(dn);
-        return rc;
-}
-
 static char *ibmebus_chomp(const char *in, size_t count)
 {
         char *out = kmalloc(count + 1, GFP_KERNEL);
@@ -204,9 +260,8 @@ static ssize_t ibmebus_store_probe(struct bus_type *bus,
                                    const char *buf, size_t count)
 {
         struct device_node *dn = NULL;
-        struct ibmebus_dev *dev;
         char *path;
-        ssize_t rc;
+        ssize_t rc = 0;
 
         path = ibmebus_chomp(buf, count);
         if (!path)
@@ -221,9 +276,8 @@ static ssize_t ibmebus_store_probe(struct bus_type *bus,
         }
 
         if ((dn = of_find_node_by_path(path))) {
-/*              dev = ibmebus_register_device_node(dn); */
+                rc = ibmebus_create_device(dn);
                 of_node_put(dn);
-                rc = IS_ERR(dev) ? PTR_ERR(dev) : count;
         } else {
                 printk(KERN_WARNING "%s: no such device node: %s\n",
                        __FUNCTION__, path);
@@ -232,7 +286,9 @@ static ssize_t ibmebus_store_probe(struct bus_type *bus,
 
 out:
         kfree(path);
-        return rc;
+        if (rc)
+                return rc;
+        return count;
 }
 
 static ssize_t ibmebus_store_remove(struct bus_type *bus,
@@ -247,7 +303,7 @@ static ssize_t ibmebus_store_remove(struct bus_type *bus,
 
         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
                                    ibmebus_match_path))) {
-/*              ibmebus_unregister_device(dev); */
+                of_device_unregister(to_of_device(dev));
 
                 kfree(path);
                 return count;
@@ -267,6 +323,7 @@ static struct bus_attribute ibmebus_bus_attrs[] = {
 };
 
 struct bus_type ibmebus_bus_type = {
+        .uevent    = of_device_uevent,
         .dev_attrs = ibmebus_dev_attrs,
         .bus_attrs = ibmebus_bus_attrs
 };
@@ -294,6 +351,13 @@ static int __init ibmebus_bus_init(void)
                 return err;
         }
 
+        err = ibmebus_create_devices(builtin_matches);
+        if (err) {
+                device_unregister(&ibmebus_bus_device);
+                bus_unregister(&ibmebus_bus_type);
+                return err;
+        }
+
         return 0;
 }
 postcore_initcall(ibmebus_bus_init);