1 files changed, 87 insertions, 0 deletions

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index d9c81e93bdd0..ea87a3cf7860 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -408,6 +408,93 @@ EXPORT_SYMBOL(of_unregister_driver);
  */
 
 /**
+ * of_device_make_bus_id - Use the device node data to assign a unique name
+ * @dev: pointer to device structure that is linked to a device tree node
+ *
+ * This routine will first try using either the dcr-reg or the reg property
+ * value to derive a unique name.  As a last resort it will use the node
+ * name followed by a unique number.
+ */
+static void of_device_make_bus_id(struct device *dev)
+{
+        static atomic_t bus_no_reg_magic;
+        struct device_node *node = dev->of_node;
+        const u32 *reg;
+        u64 addr;
+        int magic;
+
+#ifdef CONFIG_PPC_DCR
+        /*
+         * If it's a DCR based device, use 'd' for native DCRs
+         * and 'D' for MMIO DCRs.
+         */
+        reg = of_get_property(node, "dcr-reg", NULL);
+        if (reg) {
+#ifdef CONFIG_PPC_DCR_NATIVE
+                dev_set_name(dev, "d%x.%s", *reg, node->name);
+#else /* CONFIG_PPC_DCR_NATIVE */
+                u64 addr = of_translate_dcr_address(node, *reg, NULL);
+                if (addr != OF_BAD_ADDR) {
+                        dev_set_name(dev, "D%llx.%s",
+                                     (unsigned long long)addr, node->name);
+                        return;
+                }
+#endif /* !CONFIG_PPC_DCR_NATIVE */
+        }
+#endif /* CONFIG_PPC_DCR */
+
+        /*
+         * For MMIO, get the physical address
+         */
+        reg = of_get_property(node, "reg", NULL);
+        if (reg) {
+                addr = of_translate_address(node, reg);
+                if (addr != OF_BAD_ADDR) {
+                        dev_set_name(dev, "%llx.%s",
+                                     (unsigned long long)addr, node->name);
+                        return;
+                }
+        }
+
+        /*
+         * No BusID, use the node name and add a globally incremented
+         * counter (and pray...)
+         */
+        magic = atomic_add_return(1, &bus_no_reg_magic);
+        dev_set_name(dev, "%s.%d", node->name, magic - 1);
+}
+
+/**
+ * of_device_alloc - Allocate and initialize an of_device
+ * @np: device node to assign to device
+ * @bus_id: Name to assign to the device.  May be null to use default name.
+ * @parent: Parent device.
+ */
+struct of_device *of_device_alloc(struct device_node *np,
+                                  const char *bus_id,
+                                  struct device *parent)
+{
+        struct of_device *dev;
+
+        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+        if (!dev)
+                return NULL;
+
+        dev->dev.of_node = of_node_get(np);
+        dev->dev.dma_mask = &dev->archdata.dma_mask;
+        dev->dev.parent = parent;
+        dev->dev.release = of_release_dev;
+
+        if (bus_id)
+                dev_set_name(&dev->dev, "%s", bus_id);
+        else
+                of_device_make_bus_id(&dev->dev);
+
+        return dev;
+}
+EXPORT_SYMBOL(of_device_alloc);
+
+/**
  * 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