7 files changed, 81 insertions, 126 deletions

diff --git a/arch/microblaze/include/asm/prom.h b/arch/microblaze/include/asm/prom.h
index 07d1063f9aae..6c6b386cf3c6 100644
--- a/arch/microblaze/include/asm/prom.h
+++ b/arch/microblaze/include/asm/prom.h
@@ -39,10 +39,6 @@ extern struct device_node *of_chosen;
 
 extern rwlock_t devtree_lock;   /* temporary while merging */
 
-/* For updating the device tree at runtime */
-extern void of_attach_node(struct device_node *);
-extern void of_detach_node(struct device_node *);
-
 /* Other Prototypes */
 extern int early_uartlite_console(void);
 
diff --git a/arch/microblaze/kernel/prom.c b/arch/microblaze/kernel/prom.c
index cd158ef5b583..8171282a0b0d 100644
--- a/arch/microblaze/kernel/prom.c
+++ b/arch/microblaze/kernel/prom.c
@@ -197,65 +197,6 @@ struct device_node *of_find_node_by_phandle(phandle handle)
 }
 EXPORT_SYMBOL(of_find_node_by_phandle);
 
-/*
- * Plug a device node into the tree and global list.
- */
-void of_attach_node(struct device_node *np)
-{
-        unsigned long flags;
-
-        write_lock_irqsave(&devtree_lock, flags);
-        np->sibling = np->parent->child;
-        np->allnext = allnodes;
-        np->parent->child = np;
-        allnodes = np;
-        write_unlock_irqrestore(&devtree_lock, flags);
-}
-
-/*
- * "Unplug" a node from the device tree.  The caller must hold
- * a reference to the node.  The memory associated with the node
- * is not freed until its refcount goes to zero.
- */
-void of_detach_node(struct device_node *np)
-{
-        struct device_node *parent;
-        unsigned long flags;
-
-        write_lock_irqsave(&devtree_lock, flags);
-
-        parent = np->parent;
-        if (!parent)
-                goto out_unlock;
-
-        if (allnodes == np)
-                allnodes = np->allnext;
-        else {
-                struct device_node *prev;
-                for (prev = allnodes;
-                     prev->allnext != np;
-                     prev = prev->allnext)
-                        ;
-                prev->allnext = np->allnext;
-        }
-
-        if (parent->child == np)
-                parent->child = np->sibling;
-        else {
-                struct device_node *prevsib;
-                for (prevsib = np->parent->child;
-                     prevsib->sibling != np;
-                     prevsib = prevsib->sibling)
-                        ;
-                prevsib->sibling = np->sibling;
-        }
-
-        of_node_set_flag(np, OF_DETACHED);
-
-out_unlock:
-        write_unlock_irqrestore(&devtree_lock, flags);
-}
-
 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
 static struct debugfs_blob_wrapper flat_dt_blob;
 
diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
index 2ab9cbd98826..f384db815ea8 100644
--- a/arch/powerpc/include/asm/prom.h
+++ b/arch/powerpc/include/asm/prom.h
@@ -34,10 +34,6 @@ extern struct device_node *of_chosen;
 
 #define HAVE_ARCH_DEVTREE_FIXUPS
 
-/* For updating the device tree at runtime */
-extern void of_attach_node(struct device_node *);
-extern void of_detach_node(struct device_node *);
-
 #ifdef CONFIG_PPC32
 /*
  * PCI <-> OF matching functions
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 1ed2ec2ea05b..f954c718d7eb 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -817,65 +817,6 @@ struct device_node *of_find_next_cache_node(struct device_node *np)
         return NULL;
 }
 
-/*
- * Plug a device node into the tree and global list.
- */
-void of_attach_node(struct device_node *np)
-{
-        unsigned long flags;
-
-        write_lock_irqsave(&devtree_lock, flags);
-        np->sibling = np->parent->child;
-        np->allnext = allnodes;
-        np->parent->child = np;
-        allnodes = np;
-        write_unlock_irqrestore(&devtree_lock, flags);
-}
-
-/*
- * "Unplug" a node from the device tree.  The caller must hold
- * a reference to the node.  The memory associated with the node
- * is not freed until its refcount goes to zero.
- */
-void of_detach_node(struct device_node *np)
-{
-        struct device_node *parent;
-        unsigned long flags;
-
-        write_lock_irqsave(&devtree_lock, flags);
-
-        parent = np->parent;
-        if (!parent)
-                goto out_unlock;
-
-        if (allnodes == np)
-                allnodes = np->allnext;
-        else {
-                struct device_node *prev;
-                for (prev = allnodes;
-                     prev->allnext != np;
-                     prev = prev->allnext)
-                        ;
-                prev->allnext = np->allnext;
-        }
-
-        if (parent->child == np)
-                parent->child = np->sibling;
-        else {
-                struct device_node *prevsib;
-                for (prevsib = np->parent->child;
-                     prevsib->sibling != np;
-                     prevsib = prevsib->sibling)
-                        ;
-                prevsib->sibling = np->sibling;
-        }
-
-        of_node_set_flag(np, OF_DETACHED);
-
-out_unlock:
-        write_unlock_irqrestore(&devtree_lock, flags);
-}
-
 #ifdef CONFIG_PPC_PSERIES
 /*
  * Fix up the uninitialized fields in a new device node:
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 462825e03123..7cecc8fea9bd 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -2,6 +2,10 @@ config OF_FLATTREE
         bool
         depends on OF
 
+config OF_DYNAMIC
+        def_bool y
+        depends on OF && PPC_OF
+
 config OF_DEVICE
         def_bool y
         depends on OF && (SPARC || PPC_OF || MICROBLAZE)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index cf89ee6253f3..2ce58be314af 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -870,3 +870,74 @@ int prom_update_property(struct device_node *np,
 
         return 0;
 }
+
+#if defined(CONFIG_OF_DYNAMIC)
+/*
+ * Support for dynamic device trees.
+ *
+ * On some platforms, the device tree can be manipulated at runtime.
+ * The routines in this section support adding, removing and changing
+ * device tree nodes.
+ */
+
+/**
+ * of_attach_node - Plug a device node into the tree and global list.
+ */
+void of_attach_node(struct device_node *np)
+{
+        unsigned long flags;
+
+        write_lock_irqsave(&devtree_lock, flags);
+        np->sibling = np->parent->child;
+        np->allnext = allnodes;
+        np->parent->child = np;
+        allnodes = np;
+        write_unlock_irqrestore(&devtree_lock, flags);
+}
+
+/**
+ * of_detach_node - "Unplug" a node from the device tree.
+ *
+ * The caller must hold a reference to the node.  The memory associated with
+ * the node is not freed until its refcount goes to zero.
+ */
+void of_detach_node(struct device_node *np)
+{
+        struct device_node *parent;
+        unsigned long flags;
+
+        write_lock_irqsave(&devtree_lock, flags);
+
+        parent = np->parent;
+        if (!parent)
+                goto out_unlock;
+
+        if (allnodes == np)
+                allnodes = np->allnext;
+        else {
+                struct device_node *prev;
+                for (prev = allnodes;
+                     prev->allnext != np;
+                     prev = prev->allnext)
+                        ;
+                prev->allnext = np->allnext;
+        }
+
+        if (parent->child == np)
+                parent->child = np->sibling;
+        else {
+                struct device_node *prevsib;
+                for (prevsib = np->parent->child;
+                     prevsib->sibling != np;
+                     prevsib = prevsib->sibling)
+                        ;
+                prevsib->sibling = np->sibling;
+        }
+
+        of_node_set_flag(np, OF_DETACHED);
+
+out_unlock:
+        write_unlock_irqrestore(&devtree_lock, flags);
+}
+#endif /* defined(CONFIG_OF_DYNAMIC) */
+
diff --git a/include/linux/of.h b/include/linux/of.h
index dbabf86e0b7a..3cc0d7ae290e 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -184,4 +184,10 @@ extern int of_parse_phandles_with_args(struct device_node *np,
         const char *list_name, const char *cells_name, int index,
         struct device_node **out_node, const void **out_args);
 
+#if defined(CONFIG_OF_DYNAMIC)
+/* For updating the device tree at runtime */
+extern void of_attach_node(struct device_node *);
+extern void of_detach_node(struct device_node *);
+#endif
+
 #endif /* _LINUX_OF_H */