9 files changed, 209 insertions, 18 deletions

diff --git a/Documentation/ABI/testing/sysfs-firmware-ofw b/Documentation/ABI/testing/sysfs-firmware-ofw
new file mode 100644
index 000000000000..f562b188e71d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-ofw
@@ -0,0 +1,28 @@
+What:           /sys/firmware/devicetree/*
+Date:           November 2013
+Contact:        Grant Likely <grant.likely@linaro.org>
+Description:
+                When using OpenFirmware or a Flattened Device Tree to enumerate
+                hardware, the device tree structure will be exposed in this
+                directory.
+
+                It is possible for multiple device-tree directories to exist.
+                Some device drivers use a separate detached device tree which
+                have no attachment to the system tree and will appear in a
+                different subdirectory under /sys/firmware/devicetree.
+
+                Userspace must not use the /sys/firmware/devicetree/base
+                path directly, but instead should follow /proc/device-tree
+                symlink. It is possible that the absolute path will change
+                in the future, but the symlink is the stable ABI.
+
+                The /proc/device-tree symlink replaces the devicetree /proc
+                filesystem support, and has largely the same semantics and
+                should be compatible with existing userspace.
+
+                The contents of /sys/firmware/devicetree/ is a
+                hierarchy of directories, one per device tree node. The
+                directory name is the resolved path component name (node
+                name plus address). Properties are represented as files
+                in the directory. The contents of each file is the exact
+                binary data from the device tree.
diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index a8fe5aa3d34f..022b38e6a80b 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -11,7 +11,6 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/kref.h>
 #include <linux/notifier.h>
 #include <linux/spinlock.h>
 #include <linux/cpu.h>
@@ -87,7 +86,6 @@ static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
         }
 
         of_node_set_flag(dn, OF_DYNAMIC);
-        kref_init(&dn->kref);
 
         return dn;
 }
diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index f93cdf55628c..0435bb65d0aa 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -12,7 +12,6 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/kref.h>
 #include <linux/notifier.h>
 #include <linux/proc_fs.h>
 #include <linux/slab.h>
@@ -70,7 +69,6 @@ static int pSeries_reconfig_add_node(const char *path, struct property *proplist
 
         np->properties = proplist;
         of_node_set_flag(np, OF_DYNAMIC);
-        kref_init(&np->kref);
 
         np->parent = derive_parent(path);
         if (IS_ERR(np->parent)) {
diff --git a/arch/powerpc/sysdev/msi_bitmap.c b/arch/powerpc/sysdev/msi_bitmap.c
index 0968b66b4cf9..8ba60424be95 100644
--- a/arch/powerpc/sysdev/msi_bitmap.c
+++ b/arch/powerpc/sysdev/msi_bitmap.c
@@ -202,7 +202,7 @@ void __init test_of_node(void)
 
         /* There should really be a struct device_node allocator */
         memset(&of_node, 0, sizeof(of_node));
-        kref_init(&of_node.kref);
+        kref_init(&of_node.kobj.kref);
         of_node.full_name = node_name;
 
         check(0 == msi_bitmap_alloc(&bmp, size, &of_node));
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 48594f334151..3b70a468c8ab 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -23,6 +23,7 @@
 #include <linux/of.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 #include <linux/proc_fs.h>
 
 #include "of_private.h"
@@ -35,6 +36,12 @@ struct device_node *of_chosen;
 struct device_node *of_aliases;
 static struct device_node *of_stdout;
 
+static struct kset *of_kset;
+
+/*
+ * Used to protect the of_aliases; but also overloaded to hold off addition of
+ * nodes to sysfs
+ */
 DEFINE_MUTEX(of_aliases_mutex);
 
 /* use when traversing tree through the allnext, child, sibling,
@@ -92,14 +99,14 @@ int __weak of_node_to_nid(struct device_node *np)
 struct device_node *of_node_get(struct device_node *node)
 {
         if (node)
-                kref_get(&node->kref);
+                kobject_get(&node->kobj);
         return node;
 }
 EXPORT_SYMBOL(of_node_get);
 
-static inline struct device_node *kref_to_device_node(struct kref *kref)
+static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
 {
-        return container_of(kref, struct device_node, kref);
+        return container_of(kobj, struct device_node, kobj);
 }
 
 /**
@@ -109,16 +116,15 @@ static inline struct device_node *kref_to_device_node(struct kref *kref)
  *      In of_node_put() this function is passed to kref_put()
  *      as the destructor.
  */
-static void of_node_release(struct kref *kref)
+static void of_node_release(struct kobject *kobj)
 {
-        struct device_node *node = kref_to_device_node(kref);
+        struct device_node *node = kobj_to_device_node(kobj);
         struct property *prop = node->properties;
 
         /* We should never be releasing nodes that haven't been detached. */
         if (!of_node_check_flag(node, OF_DETACHED)) {
                 pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
                 dump_stack();
-                kref_init(&node->kref);
                 return;
         }
 
@@ -151,11 +157,140 @@ static void of_node_release(struct kref *kref)
 void of_node_put(struct device_node *node)
 {
         if (node)
-                kref_put(&node->kref, of_node_release);
+                kobject_put(&node->kobj);
 }
 EXPORT_SYMBOL(of_node_put);
+#else
+static void of_node_release(struct kobject *kobj)
+{
+        /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
+}
 #endif /* CONFIG_OF_DYNAMIC */
 
+struct kobj_type of_node_ktype = {
+        .release = of_node_release,
+};
+