From e7a00e4210e4cc980e3ba67ec7301af54061d14b Mon Sep 17 00:00:00 2001
From: Sebastian Reichel <sre@kernel.org>
Date: Sun, 6 Apr 2014 12:52:11 +0200
Subject: [PATCH 01/42] of: introduce of_property_read_s32

Introduce signed 32bit integer of_property_read method.

Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 include/linux/of.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/of.h b/include/linux/of.h
index 29f0adc5f3e4..30912939a610 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -760,6 +760,13 @@ static inline int of_property_read_u32(const struct device_node *np,
 	return of_property_read_u32_array(np, propname, out_value, 1);
 }
 
+static inline int of_property_read_s32(const struct device_node *np,
+				       const char *propname,
+				       s32 *out_value)
+{
+	return of_property_read_u32(np, propname, (u32*) out_value);
+}
+
 #define of_property_for_each_u32(np, propname, prop, p, u)	\
 	for (prop = of_find_property(np, propname, NULL),	\
 		p = of_prop_next_u32(prop, NULL, &u);		\

From 5063e25a302e6a83f6590d9a06bd5f6400b17430 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Fri, 3 Oct 2014 16:28:27 +0100
Subject: [PATCH 02/42] of: Eliminate of_allnodes list

The device tree structure is composed of two lists; the 'allnodes' list
which is a singly linked list containing every node in the tree, and the
child->parent structure where each parent node has a singly linked list
of children. All of the data in the allnodes list can be easily
reproduced with the parent-child lists, so of_allnodes is actually
unnecessary. Remove it entirely which saves a bit of memory and
simplifies the data structure quite a lot.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Gaurav Minocha <gaurav.minocha.os@gmail.com>
Cc: Pantelis Antoniou <pantelis@pantelis.antoniou@konsulko.com>
---
 Documentation/devicetree/of_selftest.txt | 20 +------
 Documentation/devicetree/todo.txt        |  1 -
 drivers/mfd/vexpress-sysreg.c            |  2 +-
 drivers/of/base.c                        | 53 ++++++++++--------
 drivers/of/dynamic.c                     | 13 -----
 drivers/of/fdt.c                         | 30 +++++-----
 drivers/of/pdt.c                         | 27 +++------
 drivers/of/selftest.c                    | 71 +++++++++++-------------
 include/linux/of.h                       | 11 ++--
 include/linux/of_pdt.h                   |  3 +-
 10 files changed, 98 insertions(+), 133 deletions(-)

diff --git a/Documentation/devicetree/of_selftest.txt b/Documentation/devicetree/of_selftest.txt
index 1e3d5c92b5e3..57a808b588bf 100644
--- a/Documentation/devicetree/of_selftest.txt
+++ b/Documentation/devicetree/of_selftest.txt
@@ -63,7 +63,6 @@ struct device_node {
     struct  device_node *parent;
     struct  device_node *child;
     struct  device_node *sibling;
-    struct  device_node *allnext;   /* next in list of all nodes */
     ...
  };
 
@@ -99,12 +98,6 @@ child11 -> sibling12 -> sibling13 -> sibling14 -> null
 Figure 1: Generic structure of un-flattened device tree
 
 
-*allnext: it is used to link all the nodes of DT into a list. So, for the
- above tree the list would be as follows:
-
-root->child1->child11->sibling12->sibling13->child131->sibling14->sibling2->
-child21->sibling22->sibling23->sibling3->child31->sibling32->sibling4->null
-
 Before executing OF selftest, it is required to attach the test data to
 machine's device tree (if present). So, when selftest_data_add() is called,
 at first it reads the flattened device tree data linked into the kernel image
@@ -131,11 +124,6 @@ root ('/')
  test-child01      null             null             null
 
 
-allnext list:
-
-root->testcase-data->test-child0->test-child01->test-sibling1->test-sibling2
-->test-sibling3->null
-
 Figure 2: Example test data tree to be attached to live tree.
 
 According to the scenario above, the live tree is already present so it isn't
@@ -204,8 +192,6 @@ detached and then moving up the parent nodes are removed, and eventually the
 whole tree). selftest_data_remove() calls detach_node_and_children() that uses
 of_detach_node() to detach the nodes from the live device tree.
 
-To detach a node, of_detach_node() first updates all_next linked list, by
-attaching the previous node's allnext to current node's allnext pointer. And
-then, it either updates the child pointer of given node's parent to its
-sibling or attaches the previous sibling to the given node's sibling, as
-appropriate. That is it :)
+To detach a node, of_detach_node() either updates the child pointer of given
+node's parent to its sibling or attaches the previous sibling to the given
+node's sibling, as appropriate. That is it :)
diff --git a/Documentation/devicetree/todo.txt b/Documentation/devicetree/todo.txt
index c3cf0659bd19..b5139d1de811 100644
--- a/Documentation/devicetree/todo.txt
+++ b/Documentation/devicetree/todo.txt
@@ -2,7 +2,6 @@ Todo list for devicetree:
 
 === General structure ===
 - Switch from custom lists to (h)list_head for nodes and properties structure
-- Remove of_allnodes list and iterate using list of child nodes alone
 
 === CONFIG_OF_DYNAMIC ===
 - Switch to RCU for tree updates and get rid of global spinlock
diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c
index 9e21e4fc9599..8f43ab8fd2d6 100644
--- a/drivers/mfd/vexpress-sysreg.c
+++ b/drivers/mfd/vexpress-sysreg.c
@@ -223,7 +223,7 @@ static int vexpress_sysreg_probe(struct platform_device *pdev)
 	vexpress_config_set_master(vexpress_sysreg_get_master());
 
 	/* Confirm board type against DT property, if available */
-	if (of_property_read_u32(of_allnodes, "arm,hbi", &dt_hbi) == 0) {
+	if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
 		u32 id = vexpress_get_procid(VEXPRESS_SITE_MASTER);
 		u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
 
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 3823edf2d012..1f61a908a767 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -32,8 +32,8 @@
 
 LIST_HEAD(aliases_lookup);
 
-struct device_node *of_allnodes;
-EXPORT_SYMBOL(of_allnodes);
+struct device_node *of_root;
+EXPORT_SYMBOL(of_root);
 struct device_node *of_chosen;
 struct device_node *of_aliases;
 struct device_node *of_stdout;
@@ -48,7 +48,7 @@ struct kset *of_kset;
  */
 DEFINE_MUTEX(of_mutex);
 
-/* use when traversing tree through the allnext, child, sibling,
+/* use when traversing tree through the child, sibling,
  * or parent members of struct device_node.
  */
 DEFINE_RAW_SPINLOCK(devtree_lock);
@@ -204,7 +204,7 @@ static int __init of_init(void)
 	mutex_unlock(&of_mutex);
 
 	/* Symlink in /proc as required by userspace ABI */
-	if (of_allnodes)
+	if (of_root)
 		proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
 
 	return 0;
@@ -245,6 +245,23 @@ struct property *of_find_property(const struct device_node *np,
 }
 EXPORT_SYMBOL(of_find_property);
 
+struct device_node *__of_find_all_nodes(struct device_node *prev)
+{
+	struct device_node *np;
+	if (!prev) {
+		np = of_root;
+	} else if (prev->child) {
+		np = prev->child;
+	} else {
+		/* Walk back up looking for a sibling, or the end of the structure */
+		np = prev;
+		while (np->parent && !np->sibling)
+			np = np->parent;
+		np = np->sibling; /* Might be null at the end of the tree */
+	}
+	return np;
+}
+
 /**
  * of_find_all_nodes - Get next node in global list
  * @prev:	Previous node or NULL to start iteration
@@ -259,10 +276,8 @@ struct device_node *of_find_all_nodes(struct device_node *prev)
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = prev ? prev->allnext : of_allnodes;
-	for (; np != NULL; np = np->allnext)
-		if (of_node_get(np))
-			break;
+	np = __of_find_all_nodes(prev);
+	of_node_get(np);
 	of_node_put(prev);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 	return np;
@@ -736,7 +751,7 @@ struct device_node *of_find_node_by_path(const char *path)
 	unsigned long flags;
 
 	if (strcmp(path, "/") == 0)
-		return of_node_get(of_allnodes);
+		return of_node_get(of_root);
 
 	/* The path could begin with an alias */
 	if (*path != '/') {
@@ -761,7 +776,7 @@ struct device_node *of_find_node_by_path(const char *path)
 	/* Step down the tree matching path components */
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	if (!np)
-		np = of_node_get(of_allnodes);
+		np = of_node_get(of_root);
 	while (np && *path == '/') {
 		path++; /* Increment past '/' delimiter */
 		np = __of_find_node_by_path(np, path);
@@ -790,8 +805,7 @@ struct device_node *of_find_node_by_name(struct device_node *from,
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = from ? from->allnext : of_allnodes;
-	for (; np; np = np->allnext)
+	for_each_of_allnodes_from(from, np)
 		if (np->name && (of_node_cmp(np->name, name) == 0)
 		    && of_node_get(np))
 			break;
@@ -820,8 +834,7 @@ struct device_node *of_find_node_by_type(struct device_node *from,
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = from ? from->allnext : of_allnodes;
-	for (; np; np = np->allnext)
+	for_each_of_allnodes_from(from, np)
 		if (np->type && (of_node_cmp(np->type, type) == 0)
 		    && of_node_get(np))
 			break;
@@ -852,12 +865,10 @@ struct device_node *of_find_compatible_node(struct device_node *from,
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = from ? from->allnext : of_allnodes;
-	for (; np; np = np->allnext) {
+	for_each_of_allnodes_from(from, np)
 		if (__of_device_is_compatible(np, compatible, type, NULL) &&
 		    of_node_get(np))
 			break;
-	}
 	of_node_put(from);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 	return np;
@@ -884,8 +895,7 @@ struct device_node *of_find_node_with_property(struct device_node *from,
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = from ? from->allnext : of_allnodes;
-	for (; np; np = np->allnext) {
+	for_each_of_allnodes_from(from, np) {
 		for (pp = np->properties; pp; pp = pp->next) {
 			if (of_prop_cmp(pp->name, prop_name) == 0) {
 				of_node_get(np);
@@ -967,8 +977,7 @@ struct device_node *of_find_matching_node_and_match(struct device_node *from,
 		*match = NULL;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np = from ? from->allnext : of_allnodes;
-	for (; np; np = np->allnext) {
+	for_each_of_allnodes_from(from, np) {
 		m = __of_match_node(matches, np);
 		if (m && of_node_get(np)) {
 			if (match)
@@ -1025,7 +1034,7 @@ struct device_node *of_find_node_by_phandle(phandle handle)
 		return NULL;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	for (np = of_allnodes; np; np = np->allnext)
+	for_each_of_allnodes(np)
 		if (np->phandle == handle)
 			break;
 	of_node_get(np);
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index f297891d8529..da2509d639c8 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -117,8 +117,6 @@ void __of_attach_node(struct device_node *np)
 
 	np->child = NULL;
 	np->sibling = np->parent->child;
-	np->allnext = np->parent->allnext;
-	np->parent->allnext = np;
 	np->parent->child = np;
 	of_node_clear_flag(np, OF_DETACHED);
 }
@@ -154,17 +152,6 @@ void __of_detach_node(struct device_node *np)
 	if (WARN_ON(!parent))
 		return;
 
-	if (of_allnodes == np)
-		of_allnodes = np->allnext;
-	else {
-		struct device_node *prev;
-		for (prev = of_allnodes;
-		     prev->allnext != np;
-		     prev = prev->allnext)
-			;
-		prev->allnext = np->allnext;
-	}
-
 	if (parent->child == np)
 		parent->child = np->sibling;
 	else {
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index d1ffca8b34ea..1d30b9f96466 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -145,15 +145,15 @@ static void *unflatten_dt_alloc(void **mem, unsigned long size,
  * @mem: Memory chunk to use for allocating device nodes and properties
  * @p: pointer to node in flat tree
  * @dad: Parent struct device_node
- * @allnextpp: pointer to ->allnext from last allocated device_node
  * @fpsize: Size of the node path up at the current depth.
  */
 static void * unflatten_dt_node(void *blob,
 				void *mem,
 				int *poffset,
 				struct device_node *dad,
-				struct device_node ***allnextpp,
-				unsigned long fpsize)
+				struct device_node **nodepp,
+				unsigned long fpsize,
+				bool dryrun)
 {
 	const __be32 *p;
 	struct device_node *np;
@@ -200,7 +200,7 @@ static void * unflatten_dt_node(void *blob,
 
 	np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
 				__alignof__(struct device_node));
-	if (allnextpp) {
+	if (!dryrun) {
 		char *fn;
 		of_node_init(np);
 		np->full_name = fn = ((char *)np) + sizeof(*np);
@@ -222,8 +222,6 @@ static void * unflatten_dt_node(void *blob,
 		memcpy(fn, pathp, l);
 
 		prev_pp = &np->properties;
-		**allnextpp = np;
-		*allnextpp = &np->allnext;
 		if (dad != NULL) {
 			np->parent = dad;
 			/* we temporarily use the next field as `last_child'*/
@@ -254,7 +252,7 @@ static void * unflatten_dt_node(void *blob,
 			has_name = 1;
 		pp = unflatten_dt_alloc(&mem, sizeof(struct property),
 					__alignof__(struct property));
-		if (allnextpp) {
+		if (!dryrun) {
 			/* We accept flattened tree phandles either in
 			 * ePAPR-style "phandle" properties, or the
 			 * legacy "linux,phandle" properties.  If both
@@ -296,7 +294,7 @@ static void * unflatten_dt_node(void *blob,
 		sz = (pa - ps) + 1;
 		pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
 					__alignof__(struct property));
-		if (allnextpp) {
+		if (!dryrun) {
 			pp->name = "name";
 			pp->length = sz;
 			pp->value = pp + 1;
@@ -308,7 +306,7 @@ static void * unflatten_dt_node(void *blob,
 				(char *)pp->value);
 		}
 	}
-	if (allnextpp) {
+	if (!dryrun) {
 		*prev_pp = NULL;
 		np->name = of_get_property(np, "name", NULL);
 		np->type = of_get_property(np, "device_type", NULL);
@@ -324,11 +322,13 @@ static void * unflatten_dt_node(void *blob,
 	if (depth < 0)
 		depth = 0;
 	while (*poffset > 0 && depth > old_depth)
-		mem = unflatten_dt_node(blob, mem, poffset, np, allnextpp,
-					fpsize);
+		mem = unflatten_dt_node(blob, mem, poffset, np, NULL,
+					fpsize, dryrun);
 
 	if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND)
 		pr_err("unflatten: error %d processing FDT\n", *poffset);
+	if (nodepp)
+		*nodepp = np;
 
 	return mem;
 }
@@ -352,7 +352,6 @@ static void __unflatten_device_tree(void *blob,
 	unsigned long size;
 	int start;
 	void *mem;
-	struct device_node **allnextp = mynodes;
 
 	pr_debug(" -> unflatten_device_tree()\n");
 
@@ -373,7 +372,7 @@ static void __unflatten_device_tree(void *blob,
 
 	/* First pass, scan for size */
 	start = 0;
-	size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0);
+	size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0, true);
 	size = ALIGN(size, 4);
 
 	pr_debug("  size is %lx, allocating...\n", size);
@@ -388,11 +387,10 @@ static void __unflatten_device_tree(void *blob,
 
 	/* Second pass, do actual unflattening */
 	start = 0;
-	unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
+	unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false);
 	if (be32_to_cpup(mem + size) != 0xdeadbeef)
 		pr_warning("End of tree marker overwritten: %08x\n",
 			   be32_to_cpup(mem + size));
-	*allnextp = NULL;
 
 	pr_debug(" <- unflatten_device_tree()\n");
 }
@@ -1041,7 +1039,7 @@ bool __init early_init_dt_scan(void *params)
  */
 void __init unflatten_device_tree(void)
 {
-	__unflatten_device_tree(initial_boot_params, &of_allnodes,
+	__unflatten_device_tree(initial_boot_params, &of_root,
 				early_init_dt_alloc_memory_arch);
 
 	/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
index 36b4035881b0..d2acae825af9 100644
--- a/drivers/of/pdt.c
+++ b/drivers/of/pdt.c
@@ -25,8 +25,7 @@
 
 static struct of_pdt_ops *of_pdt_prom_ops __initdata;
 
-void __initdata (*of_pdt_build_more)(struct device_node *dp,
-		struct device_node ***nextp);
+void __initdata (*of_pdt_build_more)(struct device_node *dp);
 
 #if defined(CONFIG_SPARC)
 unsigned int of_pdt_unique_id __initdata;
@@ -192,8 +191,7 @@ static struct device_node * __init of_pdt_create_node(phandle node,
 }
 
 static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
-						   phandle node,
-						   struct device_node ***nextp)
+						   phandle node)
 {
 	struct device_node *ret = NULL, *prev_sibling = NULL;
 	struct device_node *dp;
@@ -210,16 +208,12 @@ static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
 			ret = dp;
 		prev_sibling = dp;
 
-		*(*nextp) = dp;
-		*nextp = &dp->allnext;
-
 		dp->full_name = of_pdt_build_full_name(dp);
 
-		dp->child = of_pdt_build_tree(dp,
-				of_pdt_prom_ops->getchild(node), nextp);
+		dp->child = of_pdt_build_tree(dp, of_pdt_prom_ops->getchild(node));
 
 		if (of_pdt_build_more)
-			of_pdt_build_more(dp, nextp);
+			of_pdt_build_more(dp);
 
 		node = of_pdt_prom_ops->getsibling(node);
 	}
@@ -234,20 +228,17 @@ static void * __init kernel_tree_alloc(u64 size, u64 align)
 
 void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)
 {
-	struct device_node **nextp;
-
 	BUG_ON(!ops);
 	of_pdt_prom_ops = ops;
 
-	of_allnodes = of_pdt_create_node(root_node, NULL);
+	of_root = of_pdt_create_node(root_node, NULL);
 #if defined(CONFIG_SPARC)
-	of_allnodes->path_component_name = "";
+	of_root->path_component_name = "";
 #endif
-	of_allnodes->full_name = "/";
+	of_root->full_name = "/";
 
-	nextp = &of_allnodes->allnext;
-	of_allnodes->child = of_pdt_build_tree(of_allnodes,
-			of_pdt_prom_ops->getchild(of_allnodes->phandle), &nextp);
+	of_root->child = of_pdt_build_tree(of_root,
+				of_pdt_prom_ops->getchild(of_root->phandle));
 
 	/* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
 	of_alias_scan(kernel_tree_alloc);
diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index 11b873c54a77..bf7d99317a94 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -148,7 +148,7 @@ static void __init of_selftest_dynamic(void)
 
 static int __init of_selftest_check_node_linkage(struct device_node *np)
 {
-	struct device_node *child, *allnext_index = np;
+	struct device_node *child;
 	int count = 0, rc;
 
 	for_each_child_of_node(np, child) {
@@ -158,14 +158,6 @@ static int __init of_selftest_check_node_linkage(struct device_node *np)
 			return -EINVAL;
 		}
 
-		while (allnext_index && allnext_index != child)
-			allnext_index = allnext_index->allnext;
-		if (allnext_index != child) {
-			pr_err("Node %s is ordered differently in sibling and allnode lists\n",
-				 child->name);
-			return -EINVAL;
-		}
-
 		rc = of_selftest_check_node_linkage(child);
 		if (rc < 0)
 			return rc;
@@ -180,12 +172,12 @@ static void __init of_selftest_check_tree_linkage(void)
 	struct device_node *np;
 	int allnode_count = 0, child_count;
 
-	if (!of_allnodes)
+	if (!of_root)
 		return;
 
 	for_each_of_allnodes(np)
 		allnode_count++;
-	child_count = of_selftest_check_node_linkage(of_allnodes);
+	child_count = of_selftest_check_node_linkage(of_root);
 
 	selftest(child_count > 0, "Device node data structure is corrupted\n");
 	selftest(child_count == allnode_count, "allnodes list size (%i) doesn't match"
@@ -775,33 +767,29 @@ static void update_node_properties(struct device_node *np,
  */
 static int attach_node_and_children(struct device_node *np)
 {
-	struct device_node *next, *root = np, *dup;
+	struct device_node *next, *dup, *child;
 
-	/* skip root node */
-	np = np->child;
-	/* storing a copy in temporary node */
-	dup = np;
+	dup = of_find_node_by_path(np->full_name);
+	if (dup) {
+		update_node_properties(np, dup);
+		return 0;
+	}
 
-	while (dup) {
+	/* Children of the root need to be remembered for removal */
+	if (np->parent == of_root) {
 		if (WARN_ON(last_node_index >= NO_OF_NODES))
 			return -EINVAL;
-		nodes[last_node_index++] = dup;
-		dup = dup->sibling;
+		nodes[last_node_index++] = np;
 	}
-	dup = NULL;
 
-	while (np) {
-		next = np->allnext;
-		dup = of_find_node_by_path(np->full_name);
-		if (dup)
-			update_node_properties(np, dup);
-		else {
-			np->child = NULL;
-			if (np->parent == root)
-				np->parent = of_allnodes;
-			of_attach_node(np);
-		}
-		np = next;
+	child = np->child;
+	np->child = NULL;
+	np->sibling = NULL;
+	of_attach_node(np);
+	while (child) {
+		next = child->sibling;
+		attach_node_and_children(child);
+		child = next;
 	}
 
 	return 0;
@@ -846,10 +834,10 @@ static int __init selftest_data_add(void)
 		return -EINVAL;
 	}
 
-	if (!of_allnodes) {
+	if (!of_root) {
 		/* enabling flag for removing nodes */
 		selftest_live_tree = true;
-		of_allnodes = selftest_data_node;
+		of_root = selftest_data_node;
 
 		for_each_of_allnodes(np)
 			__of_attach_node_sysfs(np);
@@ -859,7 +847,14 @@ static int __init selftest_data_add(void)
 	}
 
 	/* attach the sub-tree to live tree */
-	return attach_node_and_children(selftest_data_node);
+	np = selftest_data_node->child;
+	while (np) {
+		struct device_node *next = np->sibling;
+		np->parent = of_root;
+		attach_node_and_children(np);
+		np = next;
+	}
+	return 0;
 }
 
 /**
@@ -889,10 +884,10 @@ static void selftest_data_remove(void)
 		of_node_put(of_chosen);
 		of_aliases = NULL;
 		of_chosen = NULL;
-		for_each_child_of_node(of_allnodes, np)
+		for_each_child_of_node(of_root, np)
 			detach_node_and_children(np);
-		__of_detach_node_sysfs(of_allnodes);
-		of_allnodes = NULL;
+		__of_detach_node_sysfs(of_root);
+		of_root = NULL;
 		return;
 	}
 
diff --git a/include/linux/of.h b/include/linux/of.h
index 30912939a610..f54da3b699a8 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -56,7 +56,6 @@ struct device_node {
 	struct	device_node *child;
 	struct	device_node *sibling;
 	struct	device_node *next;	/* next device of same type */
-	struct	device_node *allnext;	/* next in list of all nodes */
 	struct	kobject kobj;
 	unsigned long _flags;
 	void	*data;
@@ -108,7 +107,7 @@ static inline void of_node_put(struct device_node *node) { }
 #ifdef CONFIG_OF
 
 /* Pointer for first entry in chain of all nodes. */
-extern struct device_node *of_allnodes;
+extern struct device_node *of_root;
 extern struct device_node *of_chosen;
 extern struct device_node *of_aliases;
 extern struct device_node *of_stdout;
@@ -116,7 +115,7 @@ extern raw_spinlock_t devtree_lock;
 
 static inline bool of_have_populated_dt(void)
 {
-	return of_allnodes != NULL;
+	return of_root != NULL;
 }
 
 static inline bool of_node_is_root(const struct device_node *node)
@@ -160,6 +159,7 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag
 	clear_bit(flag, &p->_flags);
 }
 
+extern struct device_node *__of_find_all_nodes(struct device_node *prev);
 extern struct device_node *of_find_all_nodes(struct device_node *prev);
 
 /*
@@ -215,8 +215,9 @@ static inline const char *of_node_full_name(const struct device_node *np)
 	return np ? np->full_name : "<no-node>";
 }
 
-#define for_each_of_allnodes(dn) \
-	for (dn = of_allnodes; dn; dn = dn->allnext)
+#define for_each_of_allnodes_from(from, dn) \
+	for (dn = __of_find_all_nodes(from); dn; dn = __of_find_all_nodes(dn))
+#define for_each_of_allnodes(dn) for_each_of_allnodes_from(NULL, dn)
 extern struct device_node *of_find_node_by_name(struct device_node *from,
 	const char *name);
 extern struct device_node *of_find_node_by_type(struct device_node *from,
diff --git a/include/linux/of_pdt.h b/include/linux/of_pdt.h
index c65a18a0cfdf..7e09244bb679 100644
--- a/include/linux/of_pdt.h
+++ b/include/linux/of_pdt.h
@@ -39,7 +39,6 @@ extern void *prom_early_alloc(unsigned long size);
 /* for building the device tree */
 extern void of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops);
 
-extern void (*of_pdt_build_more)(struct device_node *dp,
-		struct device_node ***nextp);
+extern void (*of_pdt_build_more)(struct device_node *dp);
 
 #endif /* _LINUX_OF_PDT_H */

From 851da976dc1d72becc03e144b38c4efab9e7b361 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Tue, 4 Nov 2014 13:14:13 +0000
Subject: [PATCH 03/42] of/unittest: Remove test devices after adding them

The of_platform_populate() test cases don't remove the test devices
after they are added. Fix this by adding tests for
of_platform_depopulate().

At the same time rework the selftest() macro to return the test result
value. This makes it easy to use the macro inside an if() condition.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/selftest.c | 39 ++++++++++++++++++++++++++++-----------
 1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index bf7d99317a94..082bb2b6a5ad 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -30,15 +30,17 @@ static struct device_node *nodes[NO_OF_NODES];
 static int last_node_index;
 static bool selftest_live_tree;
 
-#define selftest(result, fmt, ...) { \
-	if (!(result)) { \
+#define selftest(result, fmt, ...) ({ \
+	bool failed = !(result); \
+	if (failed) { \
 		selftest_results.failed++; \
 		pr_err("FAIL %s():%i " fmt, __func__, __LINE__, ##__VA_ARGS__); \
 	} else { \
 		selftest_results.passed++; \
 		pr_debug("pass %s():%i\n", __func__, __LINE__); \
 	} \
-}
+	failed; \
+})
 
 static void __init of_selftest_find_node_by_name(void)
 {
@@ -694,10 +696,13 @@ static void __init of_selftest_match_node(void)
 	}
 }
 
+struct device test_bus = {
+	.init_name = "unittest-bus",
+};
 static void __init of_selftest_platform_populate(void)
 {
-	int irq;
-	struct device_node *np, *child;
+	int irq, rc;
+	struct device_node *np, *child, *grandchild;
 	struct platform_device *pdev;
 	struct of_device_id match[] = {
 		{ .compatible = "test-device", },
@@ -722,20 +727,32 @@ static void __init of_selftest_platform_populate(void)
 	irq = platform_get_irq(pdev, 0);
 	selftest(irq < 0 && irq != -EPROBE_DEFER, "device parsing error failed - %d\n", irq);
 
-	np = of_find_node_by_path("/testcase-data/platform-tests");
-	if (!np) {
-		pr_err("No testcase data in device tree\n");
+	if (selftest(np = of_find_node_by_path("/testcase-data/platform-tests"),
+		     "No testcase data in device tree\n"));
+		return;
+
+	if (selftest(!(rc = device_register(&test_bus)),
+		     "testbus registration failed; rc=%i\n", rc));
 		return;
-	}
 
 	for_each_child_of_node(np, child) {
-		struct device_node *grandchild;
-		of_platform_populate(child, match, NULL, NULL);
+		of_platform_populate(child, match, NULL, &test_bus);
 		for_each_child_of_node(child, grandchild)
 			selftest(of_find_device_by_node(grandchild),
 				 "Could not create device for node '%s'\n",
 				 grandchild->name);
 	}
+
+	of_platform_depopulate(&test_bus);
+	for_each_child_of_node(np, child) {
+		for_each_child_of_node(child, grandchild)
+			selftest(!of_find_device_by_node(grandchild),
+				 "device didn't get destroyed '%s'\n",
+				 grandchild->name);
+	}
+
+	device_unregister(&test_bus);
+	of_node_put(np);
 }
 
 /**

From 19fd74879a32fb10357e0cda9c8050f01bb3eeb8 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Tue, 4 Nov 2014 13:24:45 +0000
Subject: [PATCH 04/42] of/unittest: Rename selftest.c to unittest.c

This is unit testing code. It should use that name because it makes more
sense than 'selftest'. Rename the files to match and rename the config
variable.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/Kconfig                                            | 4 ++--
 drivers/of/Makefile                                           | 4 ++--
 drivers/of/{testcase-data => unittest-data}/testcases.dts     | 0
 .../of/{testcase-data => unittest-data}/tests-interrupts.dtsi | 0
 drivers/of/{testcase-data => unittest-data}/tests-match.dtsi  | 0
 .../of/{testcase-data => unittest-data}/tests-phandle.dtsi    | 0
 .../of/{testcase-data => unittest-data}/tests-platform.dtsi   | 0
 drivers/of/{selftest.c => unittest.c}                         | 0
 8 files changed, 4 insertions(+), 4 deletions(-)
 rename drivers/of/{testcase-data => unittest-data}/testcases.dts (100%)
 rename drivers/of/{testcase-data => unittest-data}/tests-interrupts.dtsi (100%)
 rename drivers/of/{testcase-data => unittest-data}/tests-match.dtsi (100%)
 rename drivers/of/{testcase-data => unittest-data}/tests-phandle.dtsi (100%)
 rename drivers/of/{testcase-data => unittest-data}/tests-platform.dtsi (100%)
 rename drivers/of/{selftest.c => unittest.c} (100%)

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 1a13f5b722c5..be16ce2ffd69 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -7,8 +7,8 @@ config OF
 menu "Device Tree and Open Firmware support"
 	depends on OF
 
-config OF_SELFTEST
-	bool "Device Tree Runtime self tests"
+config OF_UNITTEST
+	bool "Device Tree runtime unit tests"
 	depends on OF_IRQ && OF_EARLY_FLATTREE
 	select OF_DYNAMIC
 	select OF_RESOLVE
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index ca9209ce50cd..d90553fcd37f 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -6,8 +6,8 @@ obj-$(CONFIG_OF_PROMTREE) += pdt.o
 obj-$(CONFIG_OF_ADDRESS)  += address.o
 obj-$(CONFIG_OF_IRQ)    += irq.o
 obj-$(CONFIG_OF_NET)	+= of_net.o
-obj-$(CONFIG_OF_SELFTEST) += of_selftest.o
-of_selftest-objs := selftest.o testcase-data/testcases.dtb.o
+obj-$(CONFIG_OF_UNITTEST) += of_unittest.o
+of_unittest-objs := unittest.o unittest-data/testcases.dtb.o
 obj-$(CONFIG_OF_MDIO)	+= of_mdio.o
 obj-$(CONFIG_OF_PCI)	+= of_pci.o
 obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o
diff --git a/drivers/of/testcase-data/testcases.dts b/drivers/of/unittest-data/testcases.dts
similarity index 100%
rename from drivers/of/testcase-data/testcases.dts
rename to drivers/of/unittest-data/testcases.dts
diff --git a/drivers/of/testcase-data/tests-interrupts.dtsi b/drivers/of/unittest-data/tests-interrupts.dtsi
similarity index 100%
rename from drivers/of/testcase-data/tests-interrupts.dtsi
rename to drivers/of/unittest-data/tests-interrupts.dtsi
diff --git a/drivers/of/testcase-data/tests-match.dtsi b/drivers/of/unittest-data/tests-match.dtsi
similarity index 100%
rename from drivers/of/testcase-data/tests-match.dtsi
rename to drivers/of/unittest-data/tests-match.dtsi
diff --git a/drivers/of/testcase-data/tests-phandle.dtsi b/drivers/of/unittest-data/tests-phandle.dtsi
similarity index 100%
rename from drivers/of/testcase-data/tests-phandle.dtsi
rename to drivers/of/unittest-data/tests-phandle.dtsi
diff --git a/drivers/of/testcase-data/tests-platform.dtsi b/drivers/of/unittest-data/tests-platform.dtsi
similarity index 100%
rename from drivers/of/testcase-data/tests-platform.dtsi
rename to drivers/of/unittest-data/tests-platform.dtsi
diff --git a/drivers/of/selftest.c b/drivers/of/unittest.c
similarity index 100%
rename from drivers/of/selftest.c
rename to drivers/of/unittest.c

From b75b276bead4850c86e60747babe09be5c13d4d1 Mon Sep 17 00:00:00 2001
From: Matthias Brugger <matthias.bgg@gmail.com>
Date: Tue, 21 Oct 2014 18:27:25 +0200
Subject: [PATCH 05/42] of: Request and map make argument name constant

This patch makes the name argument from of_io_request_and_map constant.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/address.c       | 2 +-
 include/linux/of_address.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index afdb78299f61..e02828fa3acd 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -871,7 +871,7 @@ EXPORT_SYMBOL(of_iomap);
  *		return PTR_ERR(base);
  */
 void __iomem *of_io_request_and_map(struct device_node *np, int index,
-					char *name)
+					const char *name)
 {
 	struct resource res;
 	void __iomem *mem;
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index 8cb14eb393d6..d88e81be6368 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -106,7 +106,7 @@ extern int of_address_to_resource(struct device_node *dev, int index,
 				  struct resource *r);
 void __iomem *of_iomap(struct device_node *node, int index);
 void __iomem *of_io_request_and_map(struct device_node *device,
-					int index, char *name);
+					int index, const char *name);
 #else
 
 #include <linux/io.h>
@@ -123,7 +123,7 @@ static inline void __iomem *of_iomap(struct device_node *device, int index)
 }
 
 static inline void __iomem *of_io_request_and_map(struct device_node *device,
-					int index, char *name)
+					int index, const char *name)
 {
 	return IOMEM_ERR_PTR(-EINVAL);
 }

From 50ba08f301a1b0310775deeed00c9b24ba75fe8a Mon Sep 17 00:00:00 2001
From: Bjorn Helgaas <bhelgaas@google.com>
Date: Wed, 29 Oct 2014 12:15:00 -0600
Subject: [PATCH 06/42] of/fdt: Don't clear initial_boot_params if
 fdt_check_header() fails

If the device tree pointer is NULL, early_init_dt_verify() fails, leaving
initial_boot_params unchanged.  If the device tree pointer is non-NULL but
invalid, early_init_dt_verify() again fails but this time it also clears
initial_boot_params.

Leave initial_boot_params unchanged if the device tree pointer is invalid.
This doesn't fix a bug, but it makes the behavior more consistent and
easier to analyze.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/fdt.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 1d30b9f96466..535124670257 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -992,15 +992,12 @@ bool __init early_init_dt_verify(void *params)
 	if (!params)
 		return false;
 
+	/* check device tree validity */
+	if (fdt_check_header(params))
+		return false;
+
 	/* Setup flat device-tree pointer */
 	initial_boot_params = params;
-
-	/* check device tree validity */
-	if (fdt_check_header(params)) {
-		initial_boot_params = NULL;
-		return false;
-	}
-
 	return true;
 }
 

From 8cccffc52694938fc88f3d90bc7fed8460e27191 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Wed, 29 Oct 2014 17:09:32 +0100
Subject: [PATCH 07/42] of: check for size < 0 after rounding in
 early_init_dt_add_memory_arch

Memory regions passed to early_init_dt_add_memory_arch() are rounded to
PAGE_SIZE by subtracting the size of the leading fractional page from
the 'size' argument. However, size being a u64 type, if its value is
sufficiently small, the subtraction wraps around and produces a bogus
value, potentially leading to crashes.

Fix this by ignoring the memory range in such cases.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/fdt.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 535124670257..83a8e1154602 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -928,6 +928,11 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
 	const u64 phys_offset = __pa(PAGE_OFFSET);
 
 	if (!PAGE_ALIGNED(base)) {
+		if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
+			pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
+				base, base + size);
+			return;
+		}
 		size -= PAGE_SIZE - (base & ~PAGE_MASK);
 		base = PAGE_ALIGN(base);
 	}

From d94a75c13331cc00675b09d56f1a910bd53b7dd4 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Wed, 22 Oct 2014 11:44:52 +0200
Subject: [PATCH 08/42] of: Correct of_phandle_args node reference in comments

The device_node pointer in struct of_phandle_args is called "np", not
"node".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 1f61a908a767..ea3c363ef085 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1525,7 +1525,7 @@ EXPORT_SYMBOL(of_parse_phandle);
  * Returns 0 on success and fills out_args, on error returns appropriate
  * errno value.
  *
- * Caller is responsible to call of_node_put() on the returned out_args->node
+ * Caller is responsible to call of_node_put() on the returned out_args->np
  * pointer.
  *
  * Example:
@@ -1568,7 +1568,7 @@ EXPORT_SYMBOL(of_parse_phandle_with_args);
  * Returns 0 on success and fills out_args, on error returns appropriate
  * errno value.
  *
- * Caller is responsible to call of_node_put() on the returned out_args->node
+ * Caller is responsible to call of_node_put() on the returned out_args->np
  * pointer.
  *
  * Example:

From 1821dda4ae1f857f24094de88a5694e6fd9029e9 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Wed, 22 Oct 2014 11:44:53 +0200
Subject: [PATCH 09/42] of: Improve grammar for of_alias_scan() documentation

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index ea3c363ef085..3ab72f578344 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1814,14 +1814,14 @@ static void of_alias_add(struct alias_prop *ap, struct device_node *np,
 }
 
 /**
- * of_alias_scan - Scan all properties of 'aliases' node
+ * of_alias_scan - Scan all properties of the 'aliases' node
  *
- * The function scans all the properties of 'aliases' node and populate
- * the the global lookup table with the properties.  It returns the
- * number of alias_prop found, or error code in error case.
+ * The function scans all the properties of the 'aliases' node and populates
+ * the global lookup table with the properties.  It returns the
+ * number of alias properties found, or an error code in case of failure.
  *
  * @dt_alloc:	An allocator that provides a virtual address to memory
- *		for the resulting tree
+ *		for storing the resulting tree
  */
 void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 {

From c50949d3298d30f24a8eca1f9d5053f4d2b0a96e Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Wed, 22 Oct 2014 11:44:54 +0200
Subject: [PATCH 10/42] of: Grammar s/an/a/

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 3ab72f578344..8452e50f5755 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -933,7 +933,7 @@ const struct of_device_id *__of_match_node(const struct of_device_id *matches,
 }
 
 /**
- * of_match_node - Tell if an device_node has a matching of_match structure
+ * of_match_node - Tell if a device_node has a matching of_match structure
  *	@matches:	array of of device match structures to search in
  *	@node:		the of device structure to match against
  *

From c0e848d8b878c1868914de7193423cb715d49400 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Wed, 22 Oct 2014 11:44:55 +0200
Subject: [PATCH 11/42] of: Remove spaces before tabs

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 8452e50f5755..6137f18d4244 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -592,9 +592,9 @@ EXPORT_SYMBOL(of_get_parent);
  *	of_get_next_parent - Iterate to a node's parent
  *	@node:	Node to get parent of
  *
- * 	This is like of_get_parent() except that it drops the
- * 	refcount on the passed node, making it suitable for iterating
- * 	through a node's parents.
+ *	This is like of_get_parent() except that it drops the
+ *	refcount on the passed node, making it suitable for iterating
+ *	through a node's parents.
  *
  *	Returns a node pointer with refcount incremented, use
  *	of_node_put() on it when done.
@@ -1531,15 +1531,15 @@ EXPORT_SYMBOL(of_parse_phandle);
  * Example:
  *
  * phandle1: node1 {
- * 	#list-cells = <2>;
+ *	#list-cells = <2>;
  * }
  *
  * phandle2: node2 {
- * 	#list-cells = <1>;
+ *	#list-cells = <1>;
  * }
  *
  * node3 {
- * 	list = <&phandle1 1 2 &phandle2 3>;
+ *	list = <&phandle1 1 2 &phandle2 3>;
  * }
  *
  * To get a device_node of the `node2' node you may call this:
@@ -1580,7 +1580,7 @@ EXPORT_SYMBOL(of_parse_phandle_with_args);
  * }
  *
  * node3 {
- * 	list = <&phandle1 0 2 &phandle2 2 3>;
+ *	list = <&phandle1 0 2 &phandle2 2 3>;
  * }
  *
  * To get a device_node of the `node2' node you may call this:

From 5f563585ab0afa8c35b3627d65c07966f7a5080e Mon Sep 17 00:00:00 2001
From: Thierry Reding <treding@nvidia.com>
Date: Thu, 2 Oct 2014 16:01:10 +0200
Subject: [PATCH 12/42] of: Fix padding in _OF_DECLARE macro definition

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 include/linux/of.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/of.h b/include/linux/of.h
index f54da3b699a8..3c851a8f23eb 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -836,7 +836,7 @@ static inline int of_get_available_child_count(const struct device_node *np)
 		 = { .compatible = compat,				\
 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
 #else
-#define _OF_DECLARE(table, name, compat, fn, fn_type)					\
+#define _OF_DECLARE(table, name, compat, fn, fn_type)			\
 	static const struct of_device_id __of_table_##name		\
 		__attribute__((unused))					\
 		 = { .compatible = compat,				\

From 43c0767e17ac70e494b6a381b3a20be6a1a75c70 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Tue, 4 Nov 2014 10:26:26 +0000
Subject: [PATCH 13/42] of/platform: Move platform devices under
 /sys/devices/platform

Currently the devices created by drivers/of/platform.c get created at
the root of /sys/devices. This goes against the typical pattern for
sysfs where the top level /sys/devices structure contains categories of
devices, and the structure of devices is placed below that. To fix this,
make the code in drivers/of/platform.c follow the drivers/base/platform.c
behaviour, and use &platform_bus as the default parent for all new
platform_devices and amba_devices.

This change has been discussed for a long time, but nobody has actually
acted on it. Userspace code that expects to find devices under a fixed
/sys/devices/... path will be affected. It isn't /supposed/ to do that,
but if anyone complains then I'll add a default-off workaround option to
put them back into the root.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 drivers/of/platform.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 3b64d0bf5bba..7c6771986c06 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -138,7 +138,7 @@ struct platform_device *of_device_alloc(struct device_node *np,
 	}
 
 	dev->dev.of_node = of_node_get(np);
-	dev->dev.parent = parent;
+	dev->dev.parent = parent ? : &platform_bus;
 
 	if (bus_id)
 		dev_set_name(&dev->dev, "%s", bus_id);
@@ -291,7 +291,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
 
 	/* setup generic device info */
 	dev->dev.of_node = of_node_get(node);
-	dev->dev.parent = parent;
+	dev->dev.parent = parent ? : &platform_bus;
 	dev->dev.platform_data = platform_data;
 	if (bus_id)
 		dev_set_name(&dev->dev, "%s", bus_id);

From a0212ae0be5ba10b6e01b7121f86e391ae1927ae Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 14 Nov 2014 17:58:23 +1100
Subject: [PATCH 14/42] of/address: Don't throw errors on absent ranges
 properties

The core always tries to translate any "reg" property to construct the platform
device names. This results in a pile of "OF: no ranges; cannot translate" errors
in dmesg whenever we expose things like i2c devices that cannot directly translate
to the MMIO space.

Turn this into a pr_debug instead

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/address.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index e02828fa3acd..78f02f65fc48 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -477,7 +477,7 @@ static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 	ranges = of_get_property(parent, rprop, &rlen);
 #if !defined(CONFIG_PPC)
 	if (ranges == NULL) {
-		pr_err("OF: no ranges; cannot translate\n");
+		pr_debug("OF: no ranges; cannot translate\n");
 		return 1;
 	}
 #endif /* !defined(CONFIG_PPC) */

From 25c7a1de6c4b9f9eb867af4dc9215bbf9e08ef2e Mon Sep 17 00:00:00 2001
From: Kevin Cernekee <cernekee@gmail.com>
Date: Wed, 12 Nov 2014 12:54:00 -0800
Subject: [PATCH 15/42] of: Fix of_device_is_compatible() comment

This function passes back a value from __of_device_is_compatible(), which
returns a score in the range 0..11, not a bool.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 6137f18d4244..4627e0acf4ad 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -500,7 +500,7 @@ EXPORT_SYMBOL(of_device_is_compatible);
  * of_machine_is_compatible - Test root of device tree for a given compatible value
  * @compat: compatible string to look for in root node's compatible property.
  *
- * Returns true if the root node has the given value in its
+ * Returns a positive integer if the root node has the given value in its
  * compatible property.
  */
 int of_machine_is_compatible(const char *compat)

From 53a4ab96c61a34d62717b1481f6043e0b4338d74 Mon Sep 17 00:00:00 2001
From: Kevin Cernekee <cernekee@gmail.com>
Date: Wed, 12 Nov 2014 12:54:01 -0800
Subject: [PATCH 16/42] of: Change of_device_is_available() to return bool

This function can only return true or false; using a bool makes it more
obvious to the reader.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c  | 22 +++++++++++-----------
 include/linux/of.h |  6 +++---
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 4627e0acf4ad..2d5dfb8b2e65 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -522,27 +522,27 @@ EXPORT_SYMBOL(of_machine_is_compatible);
  *
  *  @device: Node to check for availability, with locks already held
  *
- *  Returns 1 if the status property is absent or set to "okay" or "ok",
- *  0 otherwise
+ *  Returns true if the status property is absent or set to "okay" or "ok",
+ *  false otherwise
  */
-static int __of_device_is_available(const struct device_node *device)
+static bool __of_device_is_available(const struct device_node *device)
 {
 	const char *status;
 	int statlen;
 
 	if (!device)
-		return 0;
+		return false;
 
 	status = __of_get_property(device, "status", &statlen);
 	if (status == NULL)
-		return 1;
+		return true;
 
 	if (statlen > 0) {
 		if (!strcmp(status, "okay") || !strcmp(status, "ok"))
-			return 1;
+			return true;
 	}
 
-	return 0;
+	return false;
 }
 
 /**
@@ -550,13 +550,13 @@ static int __of_device_is_available(const struct device_node *device)
  *
  *  @device: Node to check for availability
  *
- *  Returns 1 if the status property is absent or set to "okay" or "ok",
- *  0 otherwise
+ *  Returns true if the status property is absent or set to "okay" or "ok",
+ *  false otherwise
  */
-int of_device_is_available(const struct device_node *device)
+bool of_device_is_available(const struct device_node *device)
 {
 	unsigned long flags;
-	int res;
+	bool res;
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	res = __of_device_is_available(device);
diff --git a/include/linux/of.h b/include/linux/of.h
index 3c851a8f23eb..27635c89d8c2 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -276,7 +276,7 @@ extern int of_property_read_string_helper(struct device_node *np,
 					      const char **out_strs, size_t sz, int index);
 extern int of_device_is_compatible(const struct device_node *device,
 				   const char *);
-extern int of_device_is_available(const struct device_node *device);
+extern bool of_device_is_available(const struct device_node *device);
 extern const void *of_get_property(const struct device_node *node,
 				const char *name,
 				int *lenp);
@@ -427,9 +427,9 @@ static inline int of_device_is_compatible(const struct device_node *device,
 	return 0;
 }
 
-static inline int of_device_is_available(const struct device_node *device)
+static inline bool of_device_is_available(const struct device_node *device)
 {
-	return 0;
+	return false;
 }
 
 static inline struct property *of_find_property(const struct device_node *np,

From 08d53aa58cb162e65e25dbe31d28438657cb8e33 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Fri, 14 Nov 2014 18:05:35 +0100
Subject: [PATCH 17/42] of/fdt: export fdt blob as /sys/firmware/fdt

Create a new /sys entry '/sys/firmware/fdt' to export the FDT blob
that was passed to the kernel by the bootloader. This allows userland
applications such as kexec to access the raw binary.

The fact that this node does not reside under /sys/firmware/device-tree
is deliberate: FDT is also used on arm64 UEFI/ACPI systems to
communicate just the UEFI and ACPI entry points, but the FDT is never
unflattened and used to configure the system.

A CRC32 checksum is calculated over the entire FDT blob, and verified
at late_initcall time. The sysfs entry is instantiated only if the
checksum is valid, i.e., if the FDT blob has not been modified in the
mean time. Otherwise, a warning is printed.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/Kconfig |  1 +
 drivers/of/fdt.c   | 49 ++++++++++++++++++++++++++++------------------
 2 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index be16ce2ffd69..fbe8f8d418f7 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -23,6 +23,7 @@ config OF_FLATTREE
 	bool
 	select DTC
 	select LIBFDT
+	select CRC32
 
 config OF_EARLY_FLATTREE
 	bool
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 83a8e1154602..cb19adfb3933 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -9,6 +9,7 @@
  * version 2 as published by the Free Software Foundation.
  */
 
+#include <linux/crc32.h>
 #include <linux/kernel.h>
 #include <linux/initrd.h>
 #include <linux/memblock.h>
@@ -22,6 +23,7 @@
 #include <linux/libfdt.h>
 #include <linux/debugfs.h>
 #include <linux/serial_core.h>
+#include <linux/sysfs.h>
 
 #include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
 #include <asm/page.h>
@@ -423,6 +425,8 @@ void *initial_boot_params;
 
 #ifdef CONFIG_OF_EARLY_FLATTREE
 
+static u32 of_fdt_crc32;
+
 /**
  * res_mem_reserve_reg() - reserve all memory described in 'reg' property
  */
@@ -1003,6 +1007,8 @@ bool __init early_init_dt_verify(void *params)
 
 	/* Setup flat device-tree pointer */
 	initial_boot_params = params;
+	of_fdt_crc32 = crc32_be(~0, initial_boot_params,
+				fdt_totalsize(initial_boot_params));
 	return true;
 }
 
@@ -1080,27 +1086,32 @@ void __init unflatten_and_copy_device_tree(void)
 	unflatten_device_tree();
 }
 
-#if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
-static struct debugfs_blob_wrapper flat_dt_blob;
-
-static int __init of_flat_dt_debugfs_export_fdt(void)
+#ifdef CONFIG_SYSFS
+static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
+			       struct bin_attribute *bin_attr,
+			       char *buf, loff_t off, size_t count)
 {
-	struct dentry *d = debugfs_create_dir("device-tree", NULL);
-
-	if (!d)
-		return -ENOENT;
-
-	flat_dt_blob.data = initial_boot_params;
-	flat_dt_blob.size = fdt_totalsize(initial_boot_params);
-
-	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
-				d, &flat_dt_blob);
-	if (!d)
-		return -ENOENT;
-
-	return 0;
+	memcpy(buf, initial_boot_params + off, count);
+	return count;
 }
-module_init(of_flat_dt_debugfs_export_fdt);
+
+static int __init of_fdt_raw_init(void)
+{
+	static struct bin_attribute of_fdt_raw_attr =
+		__BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
+
+	if (!initial_boot_params)
+		return 0;
+
+	if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
+				     fdt_totalsize(initial_boot_params))) {
+		pr_warn("fdt: not creating '/sys/firmware/fdt': CRC check failed\n");
+		return 0;
+	}
+	of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
+	return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
+}
+late_initcall(of_fdt_raw_init);
 #endif
 
 #endif /* CONFIG_OF_EARLY_FLATTREE */

From 2d0747c4b68be8eb8ccfa2c538f2f5dd2ea89094 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Wed, 19 Nov 2014 22:35:39 +0000
Subject: [PATCH 18/42] of: Properly set the OF_POPULATED_BUS flag on root node

of_platform_populate() takes a subset of the device tree and turns it
into a set of platform_devices. At the same time it sets the
OF_POPULATED_BUS flag in each bus nodes so that of_platform_depopulate()
can undo the operation at a later time. However, it doesn't set the flag
on the root of the population tree which means that dynamic modifications
of the device tree at runtime will not create/destroy devices correctly.

Fix of_platform_populate() to set the OF_POPULATED_BUS flag on the node
it is called with.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Pawel Moll <pawel.moll@arm.com>
---
 drivers/of/platform.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 7c6771986c06..656cccf0e680 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -500,6 +500,7 @@ int of_platform_populate(struct device_node *root,
 		if (rc)
 			break;
 	}
+	of_node_set_flag(root, OF_POPULATED_BUS);
 
 	of_node_put(root);
 	return rc;
@@ -542,7 +543,10 @@ static int of_platform_device_destroy(struct device *dev, void *data)
  */
 void of_platform_depopulate(struct device *parent)
 {
-	device_for_each_child(parent, NULL, of_platform_device_destroy);
+	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
+		device_for_each_child(parent, NULL, of_platform_device_destroy);
+		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
+	}
 }
 EXPORT_SYMBOL_GPL(of_platform_depopulate);
 

From ef8bbd73a76197cf8362a2b43aaadc5717bd0746 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Fri, 14 Nov 2014 15:33:07 +0000
Subject: [PATCH 19/42] of: Use vargs in __of_node_alloc

The overlay code needs to construct a new full_name from the parent name
and the node name, but the current method has to allocate and then free
an temporary string which is wasteful. Fix this problem by using vargs
to pass in a format and arguments into __of_node_alloc().

At the same time remove the allocflags argument to __of_node_alloc().
The only users all use GFP_KERNEL, so there is no need to provide it as
an option. If there is ever a need later it can be added back.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/dynamic.c    | 16 ++++++++--------
 drivers/of/of_private.h |  2 +-
 drivers/of/unittest.c   |  6 +++---
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index d43f3059963b..af1b1ecd6a3d 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -274,33 +274,33 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
 /**
  * __of_node_alloc() - Create an empty device node dynamically.
  * @full_name:	Full name of the new device node
- * @allocflags:	Allocation flags (typically pass GFP_KERNEL)
  *
  * Create an empty device tree node, suitable for further modification.
  * The node data are dynamically allocated and all the node flags
  * have the OF_DYNAMIC & OF_DETACHED bits set.
  * Returns the newly allocated node or NULL on out of memory error.
  */
-struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags)
+struct device_node *__of_node_alloc(const char *fmt, ...)
 {
+	va_list vargs;
 	struct device_node *node;
 
-	node = kzalloc(sizeof(*node), allocflags);
+	node = kzalloc(sizeof(*node), GFP_KERNEL);
 	if (!node)
 		return NULL;
-
-	node->full_name = kstrdup(full_name, allocflags);
-	of_node_set_flag(node, OF_DYNAMIC);
-	of_node_set_flag(node, OF_DETACHED);
+	va_start(vargs, fmt);
+	node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs);
+	va_end(vargs);
 	if (!node->full_name)
 		goto err_free;
 
+	of_node_set_flag(node, OF_DYNAMIC);
+	of_node_set_flag(node, OF_DETACHED);
 	of_node_init(node);
 
 	return node;
 
  err_free:
-	kfree(node->full_name);
 	kfree(node);
 	return NULL;
 }
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 858e0a5d9a11..618abcad307e 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -61,7 +61,7 @@ static inline int of_property_notify(int action, struct device_node *np,
  * own the devtree lock or work on detached trees only.
  */
 struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags);
-struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags);
+__printf(1, 2) struct device_node *__of_node_alloc(const char *fmt, ...);
 
 extern const void *__of_get_property(const struct device_node *np,
 				     const char *name, int *lenp);
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 46af7019d291..7634a17af1d5 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -449,11 +449,11 @@ static void __init of_selftest_changeset(void)
 	struct of_changeset chgset;
 
 	of_changeset_init(&chgset);
-	n1 = __of_node_alloc("/testcase-data/changeset/n1", GFP_KERNEL);
+	n1 = __of_node_alloc("/testcase-data/changeset/n1");
 	selftest(n1, "testcase setup failure\n");
-	n2 = __of_node_alloc("/testcase-data/changeset/n2", GFP_KERNEL);
+	n2 = __of_node_alloc("/testcase-data/changeset/n2");
 	selftest(n2, "testcase setup failure\n");
-	n21 = __of_node_alloc("/testcase-data/changeset/n2/n21", GFP_KERNEL);
+	n21 = __of_node_alloc("/testcase-data/changeset/n2/n21");
 	selftest(n21, "testcase setup failure %p\n", n21);
 	nremove = of_find_node_by_path("/testcase-data/changeset/node-remove");
 	selftest(nremove, "testcase setup failure\n");

From e51795815ef1a7adc018cbaf05aac46e3d24eda8 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Mon, 17 Nov 2014 22:31:32 +0000
Subject: [PATCH 20/42] of: Refactor __of_node_alloc() into __of_node_dup()

Add a node argument to __of_node_alloc() and rename it to
__of_node_dup() so that it can also be used to duplicate a node with
its properties. This is important for the overlay code so that it can
create new nodes without using separate changeset items for every single
property.

At the same time rework the overlay code to use the new function and
drop the extra changeset items.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/dynamic.c    | 40 +++++++++++++++++++++++++++++-----------
 drivers/of/of_private.h |  2 +-
 drivers/of/unittest.c   | 14 ++++++++++----
 3 files changed, 40 insertions(+), 16 deletions(-)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index af1b1ecd6a3d..661ad2f5c00c 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -272,15 +272,16 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
 }
 
 /**
- * __of_node_alloc() - Create an empty device node dynamically.
- * @full_name:	Full name of the new device node
+ * __of_node_dup() - Duplicate or create an empty device node dynamically.
+ * @fmt: Format string (plus vargs) for new full name of the device node
  *
- * Create an empty device tree node, suitable for further modification.
- * The node data are dynamically allocated and all the node flags
- * have the OF_DYNAMIC & OF_DETACHED bits set.
- * Returns the newly allocated node or NULL on out of memory error.
+ * Create an device tree node, either by duplicating an empty node or by allocating
+ * an empty one suitable for further modification.  The node data are
+ * dynamically allocated and all the node flags have the OF_DYNAMIC &
+ * OF_DETACHED bits set. Returns the newly allocated node or NULL on out of
+ * memory error.
  */
-struct device_node *__of_node_alloc(const char *fmt, ...)
+struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...)
 {
 	va_list vargs;
 	struct device_node *node;
@@ -291,17 +292,34 @@ struct device_node *__of_node_alloc(const char *fmt, ...)
 	va_start(vargs, fmt);
 	node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs);
 	va_end(vargs);
-	if (!node->full_name)
-		goto err_free;
+	if (!node->full_name) {
+		kfree(node);
+		return NULL;
+	}
 
 	of_node_set_flag(node, OF_DYNAMIC);
 	of_node_set_flag(node, OF_DETACHED);
 	of_node_init(node);
 
+	/* Iterate over and duplicate all properties */
+	if (np) {
+		struct property *pp, *new_pp;
+		for_each_property_of_node(np, pp) {
+			new_pp = __of_prop_dup(pp, GFP_KERNEL);
+			if (!new_pp)
+				goto err_prop;
+			if (__of_add_property(node, new_pp)) {
+				kfree(new_pp->name);
+				kfree(new_pp->value);
+				kfree(new_pp);
+				goto err_prop;
+			}
+		}
+	}
 	return node;
 
- err_free:
-	kfree(node);
+ err_prop:
+	of_node_put(node); /* Frees the node and properties */
 	return NULL;
 }
 
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 618abcad307e..8e882e706cd8 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -61,7 +61,7 @@ static inline int of_property_notify(int action, struct device_node *np,
  * own the devtree lock or work on detached trees only.
  */
 struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags);
-__printf(1, 2) struct device_node *__of_node_alloc(const char *fmt, ...);
+__printf(2, 3) struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...);
 
 extern const void *__of_get_property(const struct device_node *np,
 				     const char *name, int *lenp);
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 7634a17af1d5..1720b039cac7 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -445,15 +445,15 @@ static void __init of_selftest_changeset(void)
 	struct property *ppadd, padd = { .name = "prop-add", .length = 0, .value = "" };
 	struct property *ppupdate, pupdate = { .name = "prop-update", .length = 5, .value = "abcd" };
 	struct property *ppremove;
-	struct device_node *n1, *n2, *n21, *nremove, *parent;
+	struct device_node *n1, *n2, *n21, *nremove, *parent, *np;
 	struct of_changeset chgset;
 
 	of_changeset_init(&chgset);
-	n1 = __of_node_alloc("/testcase-data/changeset/n1");
+	n1 = __of_node_dup(NULL, "/testcase-data/changeset/n1");
 	selftest(n1, "testcase setup failure\n");
-	n2 = __of_node_alloc("/testcase-data/changeset/n2");
+	n2 = __of_node_dup(NULL, "/testcase-data/changeset/n2");
 	selftest(n2, "testcase setup failure\n");
-	n21 = __of_node_alloc("/testcase-data/changeset/n2/n21");
+	n21 = __of_node_dup(NULL, "%s/%s", "/testcase-data/changeset/n2", "n21");
 	selftest(n21, "testcase setup failure %p\n", n21);
 	nremove = of_find_node_by_path("/testcase-data/changeset/node-remove");
 	selftest(nremove, "testcase setup failure\n");
@@ -481,6 +481,12 @@ static void __init of_selftest_changeset(void)
 	selftest(!of_changeset_apply(&chgset), "apply failed\n");
 	mutex_unlock(&of_mutex);
 
+	/* Make sure node names are constructed correctly */
+	selftest((np = of_find_node_by_path("/testcase-data/changeset/n2/n21")),
+		 "'%s' not added\n", n21->full_name);
+	if (np)
+		of_node_put(np);
+
 	mutex_lock(&of_mutex);
 	selftest(!of_changeset_revert(&chgset), "revert failed\n");
 	mutex_unlock(&of_mutex);

From da56d04c806a3e9986c66a061d7363ca3157c37b Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:33:49 +0200
Subject: [PATCH 21/42] of/resolver: Switch to new local fixups format.

The original resolver format is way too cryptic, switch
to using a tree based format that gets rid of repetitions,
is more compact and readable.

At the same time, update the selftests to using the new local fixups
format.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Squashed in testcase changes and merged similar functions]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/resolver.c                  | 128 ++++++++++++++++++++-----
 drivers/of/unittest-data/testcases.dts |  61 +++++++-----
 2 files changed, 139 insertions(+), 50 deletions(-)

diff --git a/drivers/of/resolver.c b/drivers/of/resolver.c
index aed7959f800d..640eb4cb46e3 100644
--- a/drivers/of/resolver.c
+++ b/drivers/of/resolver.c
@@ -111,7 +111,8 @@ static void __of_adjust_tree_phandles(struct device_node *node,
 		__of_adjust_tree_phandles(child, phandle_delta);
 }
 
-static int __of_adjust_phandle_ref(struct device_node *node, struct property *rprop, int value, bool is_delta)
+static int __of_adjust_phandle_ref(struct device_node *node,
+		struct property *rprop, int value)
 {
 	phandle phandle;
 	struct device_node *refnode;
@@ -181,7 +182,7 @@ static int __of_adjust_phandle_ref(struct device_node *node, struct property *rp
 			goto err_fail;
 		}
 
-		phandle = is_delta ? be32_to_cpup(sprop->value + offset) + value : value;
+		phandle = value;
 		*(__be32 *)(sprop->value + offset) = cpu_to_be32(phandle);
 	}
 
@@ -190,36 +191,97 @@ err_fail:
 	return err;
 }
 
+/* compare nodes taking into account that 'name' strips out the @ part */
+static int __of_node_name_cmp(const struct device_node *dn1,
+		const struct device_node *dn2)
+{
+	const char *n1 = strrchr(dn1->full_name, '/') ? : "/";
+	const char *n2 = strrchr(dn2->full_name, '/') ? : "/";
+
+	return of_node_cmp(n1, n2);
+}
+
 /*
  * Adjust the local phandle references by the given phandle delta.
- * Assumes the existances of a __local_fixups__ node at the root
- * of the tree. Does not take any devtree locks so make sure you
- * call this on a tree which is at the detached state.
+ * Assumes the existances of a __local_fixups__ node at the root.
+ * Assumes that __of_verify_tree_phandle_references has been called.
+ * Does not take any devtree locks so make sure you call this on a tree
+ * which is at the detached state.
  */
 static int __of_adjust_tree_phandle_references(struct device_node *node,
-		int phandle_delta)
+		struct device_node *target, int phandle_delta)
 {
-	struct device_node *child;
-	struct property *rprop;
-	int err;
+	struct device_node *child, *childtarget;
+	struct property *rprop, *sprop;
+	int err, i, count;
+	unsigned int off;
+	phandle phandle;
 
-	/* locate the symbols & fixups nodes on resolve */
-	for_each_child_of_node(node, child)
-		if (of_node_cmp(child->name, "__local_fixups__") == 0)
-			break;
-
-	/* no local fixups */
-	if (!child)
+	if (node == NULL)
 		return 0;
 
-	/* find the local fixups property */
-	for_each_property_of_node(child, rprop) {
+	for_each_property_of_node(node, rprop) {
+
 		/* skip properties added automatically */
-		if (of_prop_cmp(rprop->name, "name") == 0)
+		if (of_prop_cmp(rprop->name, "name") == 0 ||
+		    of_prop_cmp(rprop->name, "phandle") == 0 ||
+		    of_prop_cmp(rprop->name, "linux,phandle") == 0)
 			continue;
 
-		err = __of_adjust_phandle_ref(node, rprop, phandle_delta, true);
-		if (err)
+		if ((rprop->length % 4) != 0 || rprop->length == 0) {
+			pr_err("%s: Illegal property (size) '%s' @%s\n",
+					__func__, rprop->name, node->full_name);
+			return -EINVAL;
+		}
+		count = rprop->length / sizeof(__be32);
+
+		/* now find the target property */
+		for_each_property_of_node(target, sprop) {
+			if (of_prop_cmp(sprop->name, rprop->name) == 0)
+				break;
+		}
+
+		if (sprop == NULL) {
+			pr_err("%s: Could not find target property '%s' @%s\n",
+					__func__, rprop->name, node->full_name);
+			return -EINVAL;
+		}
+
+		for (i = 0; i < count; i++) {
+			off = be32_to_cpu(((__be32 *)rprop->value)[i]);
+			/* make sure the offset doesn't overstep (even wrap) */
+			if (off >= sprop->length ||
+					(off + 4) > sprop->length) {
+				pr_err("%s: Illegal property '%s' @%s\n",
+						__func__, rprop->name,
+						node->full_name);
+				return -EINVAL;
+			}
+
+			if (phandle_delta) {
+				/* adjust */
+				phandle = be32_to_cpu(*(__be32 *)(sprop->value + off));
+				phandle += phandle_delta;
+				*(__be32 *)(sprop->value + off) = cpu_to_be32(phandle);
+			}
+		}
+	}
+
+	for_each_child_of_node(node, child) {
+
+		for_each_child_of_node(target, childtarget)
+			if (__of_node_name_cmp(child, childtarget) == 0)
+				break;
+
+		if (!childtarget) {
+			pr_err("%s: Could not find target child '%s' @%s\n",
+					__func__, child->name, node->full_name);
+			return -EINVAL;
+		}
+
+		err = __of_adjust_tree_phandle_references(child, childtarget,
+				phandle_delta);
+		if (err != 0)
 			return err;
 	}
 
@@ -241,7 +303,7 @@ static int __of_adjust_tree_phandle_references(struct device_node *node,
  */
 int of_resolve_phandles(struct device_node *resolve)
 {
-	struct device_node *child, *refnode;
+	struct device_node *child, *childroot, *refnode;
 	struct device_node *root_sym, *resolve_sym, *resolve_fix;
 	struct property *rprop;
 	const char *refpath;
@@ -255,9 +317,23 @@ int of_resolve_phandles(struct device_node *resolve)
 	/* first we need to adjust the phandles */
 	phandle_delta = of_get_tree_max_phandle() + 1;
 	__of_adjust_tree_phandles(resolve, phandle_delta);
-	err = __of_adjust_tree_phandle_references(resolve, phandle_delta);
-	if (err != 0)
-		return err;
+
+	/* locate the local fixups */
+	childroot = NULL;
+	for_each_child_of_node(resolve, childroot)
+		if (of_node_cmp(childroot->name, "__local_fixups__") == 0)
+			break;
+
+	if (childroot != NULL) {
+		/* resolve root is guaranteed to be the '/' */
+		err = __of_adjust_tree_phandle_references(childroot,
+				resolve, 0);
+		if (err != 0)
+			return err;
+
+		BUG_ON(__of_adjust_tree_phandle_references(childroot,
+				resolve, phandle_delta));
+	}
 
 	root_sym = NULL;
 	resolve_sym = NULL;
@@ -322,7 +398,7 @@ int of_resolve_phandles(struct device_node *resolve)
 		pr_debug("%s: %s phandle is 0x%08x\n",
 				__func__, rprop->name, phandle);
 
-		err = __of_adjust_phandle_ref(resolve, rprop, phandle, false);
+		err = __of_adjust_phandle_ref(resolve, rprop, phandle);
 		if (err)
 			break;
 	}
diff --git a/drivers/of/unittest-data/testcases.dts b/drivers/of/unittest-data/testcases.dts
index 6994e15c24bf..b6bc41b2a185 100644
--- a/drivers/of/unittest-data/testcases.dts
+++ b/drivers/of/unittest-data/testcases.dts
@@ -23,28 +23,41 @@
  * this a kernel-internal data format.
  */
 / { __local_fixups__ {
-	fixup = "/testcase-data/testcase-device2:interrupt-parent:0",
-		"/testcase-data/testcase-device1:interrupt-parent:0",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:60",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:52",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:44",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:36",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:24",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:8",
-		"/testcase-data/interrupts/interrupts-extended0:interrupts-extended:0",
-		"/testcase-data/interrupts/interrupts1:interrupt-parent:0",
-		"/testcase-data/interrupts/interrupts0:interrupt-parent:0",
-		"/testcase-data/interrupts/intmap1:interrupt-map:12",
-		"/testcase-data/interrupts/intmap0:interrupt-map:52",
-		"/testcase-data/interrupts/intmap0:interrupt-map:36",
-		"/testcase-data/interrupts/intmap0:interrupt-map:16",
-		"/testcase-data/interrupts/intmap0:interrupt-map:4",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list-bad-args:12",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list-bad-args:0",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:56",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:52",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:40",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:24",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:8",
-		"/testcase-data/phandle-tests/consumer-a:phandle-list:0";
+	testcase-data {
+		phandle-tests {
+			consumer-a {
+				phandle-list = <0x00000000 0x00000008
+						0x00000018 0x00000028
+						0x00000034 0x00000038>;
+				phandle-list-bad-args = <0x00000000 0x0000000c>;
+			};
+		};
+		interrupts {
+			intmap0 {
+				interrupt-map = <0x00000004 0x00000010
+						 0x00000024 0x00000034>;
+			};
+			intmap1 {
+				interrupt-map = <0x0000000c>;
+			};
+			interrupts0 {
+				interrupt-parent = <0x00000000>;
+			};
+			interrupts1 {
+				interrupt-parent = <0x00000000>;
+			};
+			interrupts-extended0 {
+				interrupts-extended = <0x00000000 0x00000008
+						       0x00000018 0x00000024
+						       0x0000002c 0x00000034
+						       0x0000003c>;
+			};
+		};
+		testcase-device1 {
+			interrupt-parent = <0x00000000>;
+		};
+		testcase-device2 {
+			interrupt-parent = <0x00000000>;
+		};
+	};
 }; };

From b53a2340d0d30468b7315992ba77fe188c3bc5c8 Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:33:53 +0200
Subject: [PATCH 22/42] of/reconfig: Add of_reconfig_get_state_change() of
 notifier helper.

Introduce of_reconfig_get_state_change() which allows an of notifier
to query about device state changes.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/dynamic.c | 96 ++++++++++++++++++++++++++++++++++++++++++++
 include/linux/of.h   |  7 ++++
 2 files changed, 103 insertions(+)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 661ad2f5c00c..6659c39ab3aa 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -85,6 +85,102 @@ int of_reconfig_notify(unsigned long action, void *p)
 	return notifier_to_errno(rc);
 }
 
+/*
+ * of_reconfig_get_state_change()	- Returns new state of device
+ * @action	- action of the of notifier
+ * @arg		- argument of the of notifier
+ *
+ * Returns the new state of a device based on the notifier used.
+ * Returns 0 on device going from enabled to disabled, 1 on device
+ * going from disabled to enabled and -1 on no change.
+ */
+int of_reconfig_get_state_change(unsigned long action, void *arg)
+{
+	struct device_node *dn;
+	struct property *prop, *old_prop;
+	struct of_prop_reconfig *pr;
+	int is_status, status_state, old_status_state, prev_state, new_state;
+
+	/* figure out if a device should be created or destroyed */
+	dn = NULL;
+	prop = old_prop = NULL;
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		dn = arg;
+		prop = of_find_property(dn, "status", NULL);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		pr = arg;
+		dn = pr->dn;
+		prop = pr->prop;
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		pr = arg;
+		dn = pr->dn;
+		prop = pr->prop;
+		old_prop = pr->old_prop;
+		break;
+	default:
+		return OF_RECONFIG_NO_CHANGE;
+	}
+
+	is_status = 0;
+	status_state = -1;
+	old_status_state = -1;
+	prev_state = -1;
+	new_state = -1;
+
+	if (prop && !strcmp(prop->name, "status")) {
+		is_status = 1;
+		status_state = !strcmp(prop->value, "okay") ||
+			       !strcmp(prop->value, "ok");
+		if (old_prop)
+			old_status_state = !strcmp(old_prop->value, "okay") ||
+					   !strcmp(old_prop->value, "ok");
+	}
+
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		prev_state = 0;
+		/* -1 & 0 status either missing or okay */
+		new_state = status_state != 0;
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		/* -1 & 0 status either missing or okay */
+		prev_state = status_state != 0;
+		new_state = 0;
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		if (is_status) {
+			/* no status property -> enabled (legacy) */
+			prev_state = 1;
+			new_state = status_state;
+		}
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		if (is_status) {
+			prev_state = status_state;
+			/* no status property -> enabled (legacy) */
+			new_state = 1;
+		}
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		if (is_status) {
+			prev_state = old_status_state != 0;
+			new_state = status_state != 0;
+		}
+		break;
+	}
+
+	if (prev_state == new_state)
+		return OF_RECONFIG_NO_CHANGE;
+
+	return new_state ? OF_RECONFIG_CHANGE_ADD : OF_RECONFIG_CHANGE_REMOVE;
+}
+EXPORT_SYMBOL_GPL(of_reconfig_get_state_change);
+
 int of_property_notify(int action, struct device_node *np,
 		       struct property *prop, struct property *oldprop)
 {
diff --git a/include/linux/of.h b/include/linux/of.h
index 27635c89d8c2..8e3a264c869c 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -327,6 +327,7 @@ struct of_prop_reconfig {
 extern int of_reconfig_notifier_register(struct notifier_block *);
 extern int of_reconfig_notifier_unregister(struct notifier_block *);
 extern int of_reconfig_notify(unsigned long, void *);
+extern int of_reconfig_get_state_change(unsigned long action, void *arg);
 
 extern int of_attach_node(struct device_node *);
 extern int of_detach_node(struct device_node *);
@@ -887,6 +888,12 @@ struct of_changeset {
 	struct list_head entries;
 };
 
+enum of_reconfig_change {
+	OF_RECONFIG_NO_CHANGE = 0,
+	OF_RECONFIG_CHANGE_ADD,
+	OF_RECONFIG_CHANGE_REMOVE,
+};
+
 #ifdef CONFIG_OF_DYNAMIC
 extern void of_changeset_init(struct of_changeset *ocs);
 extern void of_changeset_destroy(struct of_changeset *ocs);

From f6892d193fb9d694a1b50550649ba6e82f8abec1 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Fri, 21 Nov 2014 15:14:58 +0000
Subject: [PATCH 23/42] of/reconfig: Add empty stubs for the of_reconfig
 methods

To simplify subsystem setup code, make empty stubs for the
of_reconfig_*() methods. This is particularly useful for registering and
unregistering the notifiers so that it doesn't impact the flow of the
subsystem setup code.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 include/linux/of.h | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

diff --git a/include/linux/of.h b/include/linux/of.h
index 8e3a264c869c..b59ee21933a4 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -324,11 +324,6 @@ struct of_prop_reconfig {
 	struct property		*old_prop;
 };
 
-extern int of_reconfig_notifier_register(struct notifier_block *);
-extern int of_reconfig_notifier_unregister(struct notifier_block *);
-extern int of_reconfig_notify(unsigned long, void *);
-extern int of_reconfig_get_state_change(unsigned long action, void *arg);
-
 extern int of_attach_node(struct device_node *);
 extern int of_detach_node(struct device_node *);
 
@@ -895,6 +890,11 @@ enum of_reconfig_change {
 };
 
 #ifdef CONFIG_OF_DYNAMIC
+extern int of_reconfig_notifier_register(struct notifier_block *);
+extern int of_reconfig_notifier_unregister(struct notifier_block *);
+extern int of_reconfig_notify(unsigned long, void *);
+extern int of_reconfig_get_state_change(unsigned long action, void *arg);
+
 extern void of_changeset_init(struct of_changeset *ocs);
 extern void of_changeset_destroy(struct of_changeset *ocs);
 extern int of_changeset_apply(struct of_changeset *ocs);
@@ -932,7 +932,24 @@ static inline int of_changeset_update_property(struct of_changeset *ocs,
 {
 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
 }
-#endif
+#else /* CONFIG_OF_DYNAMIC */
+static inline int of_reconfig_notifier_register(struct notifier_block *nb)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_notify(unsigned long action, void *arg)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_get_state_change(unsigned long action, void *arg)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_OF_DYNAMIC */
 
 /* CONFIG_OF_RESOLVE api */
 extern int of_resolve_phandles(struct device_node *tree);

From 00aa37206e1a54dae61a0dba96bf2ee0938b99d7 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Fri, 14 Nov 2014 14:34:55 +0000
Subject: [PATCH 24/42] of/reconfig: Add debug output for OF_RECONFIG notifiers

Add some additional debug output to cover OF_RECONFIG notifier activity.
At the same time, refactor the changeset debug output to use the same
strings as the notifier debug output.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/dynamic.c | 48 +++++++++++++++++++++++++++++---------------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 6659c39ab3aa..cc106529dca8 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -77,10 +77,38 @@ int of_reconfig_notifier_unregister(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
 
+#ifdef DEBUG
+const char *action_names[] = {
+	[OF_RECONFIG_ATTACH_NODE] = "ATTACH_NODE",
+	[OF_RECONFIG_DETACH_NODE] = "DETACH_NODE",
+	[OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY",
+	[OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY",
+	[OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY",
+};
+#endif
+
 int of_reconfig_notify(unsigned long action, void *p)
 {
 	int rc;
+#ifdef DEBUG
+	struct device_node *dn = p;
+	struct of_prop_reconfig *pr = p;
 
+	switch (action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		pr_debug("of/notify %-15s %s\n", action_names[action],
+			dn->full_name);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		pr_debug("of/notify %-15s %s:%s\n", action_names[action],
+			pr->dn->full_name, pr->prop->name);
+		break;
+
+	}
+#endif
 	rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
 	return notifier_to_errno(rc);
 }
@@ -431,27 +459,15 @@ static void __of_changeset_entry_dump(struct of_changeset_entry *ce)
 {
 	switch (ce->action) {
 	case OF_RECONFIG_ADD_PROPERTY:
-		pr_debug("%p: %s %s/%s\n",
-			ce, "ADD_PROPERTY   ", ce->np->full_name,
-			ce->prop->name);
-		break;
 	case OF_RECONFIG_REMOVE_PROPERTY:
-		pr_debug("%p: %s %s/%s\n",
-			ce, "REMOVE_PROPERTY", ce->np->full_name,
-			ce->prop->name);
-		break;
 	case OF_RECONFIG_UPDATE_PROPERTY:
-		pr_debug("%p: %s %s/%s\n",
-			ce, "UPDATE_PROPERTY", ce->np->full_name,
-			ce->prop->name);
+		pr_debug("of/cset<%p> %-15s %s/%s\n", ce, action_names[ce->action],
+			ce->np->full_name, ce->prop->name);
 		break;
 	case OF_RECONFIG_ATTACH_NODE:
-		pr_debug("%p: %s %s\n",
-			ce, "ATTACH_NODE    ", ce->np->full_name);
-		break;
 	case OF_RECONFIG_DETACH_NODE:
-		pr_debug("%p: %s %s\n",
-			ce, "DETACH_NODE    ", ce->np->full_name);
+		pr_debug("of/cset<%p> %-15s %s\n", ce, action_names[ce->action],
+			ce->np->full_name);
 		break;
 	}
 }

From f5242e5a883bf1c1aba6bfd87b85e7dda0e62191 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Mon, 24 Nov 2014 17:58:01 +0000
Subject: [PATCH 25/42] of/reconfig: Always use the same structure for
 notifiers

The OF_RECONFIG notifier callback uses a different structure depending
on whether it is a node change or a property change. This is silly, and
not very safe. Rework the code to use the same data structure regardless
of the type of notifier.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: <linuxppc-dev@lists.ozlabs.org>
---
 arch/powerpc/mm/numa.c                        |  3 +-
 arch/powerpc/platforms/pseries/hotplug-cpu.c  |  7 ++--
 .../platforms/pseries/hotplug-memory.c        | 15 ++++---
 arch/powerpc/platforms/pseries/iommu.c        |  5 ++-
 arch/powerpc/platforms/pseries/setup.c        |  5 ++-
 drivers/crypto/nx/nx-842.c                    |  4 +-
 drivers/of/dynamic.c                          | 41 ++++++++++---------
 include/linux/of.h                            | 23 ++++++-----
 8 files changed, 54 insertions(+), 49 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index b9d1dfdbe5bb..9fe6002c1d5a 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1711,12 +1711,11 @@ static void stage_topology_update(int core_id)
 static int dt_update_callback(struct notifier_block *nb,
 				unsigned long action, void *data)
 {
-	struct of_prop_reconfig *update;
+	struct of_reconfig_data *update = data;
 	int rc = NOTIFY_DONE;
 
 	switch (action) {
 	case OF_RECONFIG_UPDATE_PROPERTY:
-		update = (struct of_prop_reconfig *)data;
 		if (!of_prop_cmp(update->dn->type, "cpu") &&
 		    !of_prop_cmp(update->prop->name, "ibm,associativity")) {
 			u32 core_id;
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 5c375f93c669..f30cf4d136a4 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -340,16 +340,17 @@ static void pseries_remove_processor(struct device_node *np)
 }
 
 static int pseries_smp_notifier(struct notifier_block *nb,
-				unsigned long action, void *node)
+				unsigned long action, void *data)
 {
+	struct of_reconfig_data *rd = data;
 	int err = 0;
 
 	switch (action) {
 	case OF_RECONFIG_ATTACH_NODE:
-		err = pseries_add_processor(node);
+		err = pseries_add_processor(rd->dn);
 		break;
 	case OF_RECONFIG_DETACH_NODE:
-		pseries_remove_processor(node);
+		pseries_remove_processor(rd->dn);
 		break;
 	}
 	return notifier_from_errno(err);
diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index 3c4c0dcd90d3..1bbb78fab530 100644
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -183,7 +183,7 @@ static int pseries_add_mem_node(struct device_node *np)
 	return (ret < 0) ? -EINVAL : 0;
 }
 
-static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
+static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
 {
 	struct of_drconf_cell *new_drmem, *old_drmem;
 	unsigned long memblock_size;
@@ -232,22 +232,21 @@ static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
 }
 
 static int pseries_memory_notifier(struct notifier_block *nb,
-				   unsigned long action, void *node)
+				   unsigned long action, void *data)
 {
-	struct of_prop_reconfig *pr;
+	struct of_reconfig_data *rd = data;
 	int err = 0;
 
 	switch (action) {
 	case OF_RECONFIG_ATTACH_NODE:
-		err = pseries_add_mem_node(node);
+		err = pseries_add_mem_node(rd->dn);
 		break;
 	case OF_RECONFIG_DETACH_NODE:
-		err = pseries_remove_mem_node(node);
+		err = pseries_remove_mem_node(rd->dn);
 		break;
 	case OF_RECONFIG_UPDATE_PROPERTY:
-		pr = (struct of_prop_reconfig *)node;
-		if (!strcmp(pr->prop->name, "ibm,dynamic-memory"))
-			err = pseries_update_drconf_memory(pr);
+		if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
+			err = pseries_update_drconf_memory(rd);
 		break;
 	}
 	return notifier_from_errno(err);
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index e32e00976a94..3e5bfdafee63 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1251,10 +1251,11 @@ static struct notifier_block iommu_mem_nb = {
 	.notifier_call = iommu_mem_notifier,
 };
 
-static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *node)
+static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *data)
 {
 	int err = NOTIFY_OK;
-	struct device_node *np = node;
+	struct of_reconfig_data *rd = data;
+	struct device_node *np = rd->dn;
 	struct pci_dn *pci = PCI_DN(np);
 	struct direct_window *window;
 
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 125c589eeef5..ed8a90022a3d 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -251,9 +251,10 @@ static void __init pseries_discover_pic(void)
 	       " interrupt-controller\n");
 }
 
-static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *node)
+static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *data)
 {
-	struct device_node *np = node;
+	struct of_reconfig_data *rd = data;
+	struct device_node *np = rd->dn;
 	struct pci_dn *pci = NULL;
 	int err = NOTIFY_OK;
 
diff --git a/drivers/crypto/nx/nx-842.c b/drivers/crypto/nx/nx-842.c
index 061407d59520..887196e9b50c 100644
--- a/drivers/crypto/nx/nx-842.c
+++ b/drivers/crypto/nx/nx-842.c
@@ -1009,9 +1009,9 @@ error_out:
  *		notifier_to_errno() to decode this value
  */
 static int nx842_OF_notifier(struct notifier_block *np, unsigned long action,
-			     void *update)
+			     void *data)
 {
-	struct of_prop_reconfig *upd = update;
+	struct of_reconfig_data *upd = data;
 	struct nx842_devdata *local_devdata;
 	struct device_node *node = NULL;
 
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index cc106529dca8..3351ef408125 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -87,18 +87,17 @@ const char *action_names[] = {
 };
 #endif
 
-int of_reconfig_notify(unsigned long action, void *p)
+int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
 {
 	int rc;
 #ifdef DEBUG
-	struct device_node *dn = p;
-	struct of_prop_reconfig *pr = p;
+	struct of_reconfig_data *pr = p;
 
 	switch (action) {
 	case OF_RECONFIG_ATTACH_NODE:
 	case OF_RECONFIG_DETACH_NODE:
 		pr_debug("of/notify %-15s %s\n", action_names[action],
-			dn->full_name);
+			pr->dn->full_name);
 		break;
 	case OF_RECONFIG_ADD_PROPERTY:
 	case OF_RECONFIG_REMOVE_PROPERTY:
@@ -122,31 +121,22 @@ int of_reconfig_notify(unsigned long action, void *p)
  * Returns 0 on device going from enabled to disabled, 1 on device
  * going from disabled to enabled and -1 on no change.
  */
-int of_reconfig_get_state_change(unsigned long action, void *arg)
+int of_reconfig_get_state_change(unsigned long action, struct of_reconfig_data *pr)
 {
-	struct device_node *dn;
-	struct property *prop, *old_prop;
-	struct of_prop_reconfig *pr;
+	struct property *prop, *old_prop = NULL;
 	int is_status, status_state, old_status_state, prev_state, new_state;
 
 	/* figure out if a device should be created or destroyed */
-	dn = NULL;
-	prop = old_prop = NULL;
 	switch (action) {
 	case OF_RECONFIG_ATTACH_NODE:
 	case OF_RECONFIG_DETACH_NODE:
-		dn = arg;
-		prop = of_find_property(dn, "status", NULL);
+		prop = of_find_property(pr->dn, "status", NULL);
 		break;
 	case OF_RECONFIG_ADD_PROPERTY:
 	case OF_RECONFIG_REMOVE_PROPERTY:
-		pr = arg;
-		dn = pr->dn;
 		prop = pr->prop;
 		break;
 	case OF_RECONFIG_UPDATE_PROPERTY:
-		pr = arg;
-		dn = pr->dn;
 		prop = pr->prop;
 		old_prop = pr->old_prop;
 		break;
@@ -212,7 +202,7 @@ EXPORT_SYMBOL_GPL(of_reconfig_get_state_change);
 int of_property_notify(int action, struct device_node *np,
 		       struct property *prop, struct property *oldprop)
 {
-	struct of_prop_reconfig pr;
+	struct of_reconfig_data pr;
 
 	/* only call notifiers if the node is attached */
 	if (!of_node_is_attached(np))
@@ -250,8 +240,12 @@ void __of_attach_node(struct device_node *np)
  */
 int of_attach_node(struct device_node *np)
 {
+	struct of_reconfig_data rd;
 	unsigned long flags;
 
+	memset(&rd, 0, sizeof(rd));
+	rd.dn = np;
+
 	mutex_lock(&of_mutex);
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	__of_attach_node(np);
@@ -260,7 +254,7 @@ int of_attach_node(struct device_node *np)
 	__of_attach_node_sysfs(np);
 	mutex_unlock(&of_mutex);
 
-	of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np);
+	of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, &rd);
 
 	return 0;
 }
@@ -298,9 +292,13 @@ void __of_detach_node(struct device_node *np)
  */
 int of_detach_node(struct device_node *np)
 {
+	struct of_reconfig_data rd;
 	unsigned long flags;
 	int rc = 0;
 
+	memset(&rd, 0, sizeof(rd));
+	rd.dn = np;
+
 	mutex_lock(&of_mutex);
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	__of_detach_node(np);
@@ -309,7 +307,7 @@ int of_detach_node(struct device_node *np)
 	__of_detach_node_sysfs(np);
 	mutex_unlock(&of_mutex);
 
-	of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
+	of_reconfig_notify(OF_RECONFIG_DETACH_NODE, &rd);
 
 	return rc;
 }
@@ -505,6 +503,7 @@ static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
 
 static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert)
 {
+	struct of_reconfig_data rd;
 	struct of_changeset_entry ce_inverted;
 	int ret;
 
@@ -516,7 +515,9 @@ static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool reve
 	switch (ce->action) {
 	case OF_RECONFIG_ATTACH_NODE:
 	case OF_RECONFIG_DETACH_NODE:
-		ret = of_reconfig_notify(ce->action, ce->np);
+		memset(&rd, 0, sizeof(rd));
+		rd.dn = ce->np;
+		ret = of_reconfig_notify(ce->action, &rd);
 		break;
 	case OF_RECONFIG_ADD_PROPERTY:
 	case OF_RECONFIG_REMOVE_PROPERTY:
diff --git a/include/linux/of.h b/include/linux/of.h
index b59ee21933a4..fe1dec87fd68 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -73,6 +73,12 @@ struct of_phandle_args {
 	uint32_t args[MAX_PHANDLE_ARGS];
 };
 
+struct of_reconfig_data {
+	struct device_node	*dn;
+	struct property		*prop;
+	struct property		*old_prop;
+};
+
 /* initialize a node */
 extern struct kobj_type of_node_ktype;
 static inline void of_node_init(struct device_node *node)
@@ -318,12 +324,6 @@ extern int of_update_property(struct device_node *np, struct property *newprop);
 #define OF_RECONFIG_REMOVE_PROPERTY	0x0004
 #define OF_RECONFIG_UPDATE_PROPERTY	0x0005
 
-struct of_prop_reconfig {
-	struct device_node	*dn;
-	struct property		*prop;
-	struct property		*old_prop;
-};
-
 extern int of_attach_node(struct device_node *);
 extern int of_detach_node(struct device_node *);
 
@@ -892,8 +892,9 @@ enum of_reconfig_change {
 #ifdef CONFIG_OF_DYNAMIC
 extern int of_reconfig_notifier_register(struct notifier_block *);
 extern int of_reconfig_notifier_unregister(struct notifier_block *);
-extern int of_reconfig_notify(unsigned long, void *);
-extern int of_reconfig_get_state_change(unsigned long action, void *arg);
+extern int of_reconfig_notify(unsigned long, struct of_reconfig_data *rd);
+extern int of_reconfig_get_state_change(unsigned long action,
+					struct of_reconfig_data *arg);
 
 extern void of_changeset_init(struct of_changeset *ocs);
 extern void of_changeset_destroy(struct of_changeset *ocs);
@@ -941,11 +942,13 @@ static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
 {
 	return -EINVAL;
 }
-static inline int of_reconfig_notify(unsigned long action, void *arg)
+static inline int of_reconfig_notify(unsigned long action,
+				     struct of_reconfig_data *arg)
 {
 	return -EINVAL;
 }
-static inline int of_reconfig_get_state_change(unsigned long action, void *arg)
+static inline int of_reconfig_get_state_change(unsigned long action,
+						struct of_reconfig_data *arg)
 {
 	return -EINVAL;
 }

From 801d728c10db4b28e01590b46bf1f0df930760cc Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:36:01 +0200
Subject: [PATCH 26/42] of/reconfig: Add OF_DYNAMIC notifier for
 platform_bus_type

Add OF notifier handler needed for creating/destroying platform devices
according to dynamic runtime changes in the DT live tree.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/base/platform.c     |  1 +
 drivers/of/platform.c       | 55 +++++++++++++++++++++++++++++++++++++
 include/linux/of_platform.h |  6 ++++
 3 files changed, 62 insertions(+)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index b2afc29403f9..233ececd15a3 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1006,6 +1006,7 @@ int __init platform_bus_init(void)
 	error =  bus_register(&platform_bus_type);
 	if (error)
 		device_unregister(&platform_bus);
+	of_platform_register_reconfig_notifier();
 	return error;
 }
 
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 656cccf0e680..cd87a36495be 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -550,4 +550,59 @@ void of_platform_depopulate(struct device *parent)
 }
 EXPORT_SYMBOL_GPL(of_platform_depopulate);
 
+#ifdef CONFIG_OF_DYNAMIC
+static int of_platform_notify(struct notifier_block *nb,
+				unsigned long action, void *arg)
+{
+	struct of_reconfig_data *rd = arg;
+	struct platform_device *pdev_parent, *pdev;
+	bool children_left;
+
+	switch (of_reconfig_get_state_change(action, rd)) {
+	case OF_RECONFIG_CHANGE_ADD:
+		/* verify that the parent is a bus */
+		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
+			return NOTIFY_OK;	/* not for us */
+
+		/* pdev_parent may be NULL when no bus platform device */
+		pdev_parent = of_find_device_by_node(rd->dn->parent);
+		pdev = of_platform_device_create(rd->dn, NULL,
+				pdev_parent ? &pdev_parent->dev : NULL);
+		of_dev_put(pdev_parent);
+
+		if (pdev == NULL) {
+			pr_err("%s: failed to create for '%s'\n",
+					__func__, rd->dn->full_name);
+			/* of_platform_device_create tosses the error code */
+			return notifier_from_errno(-EINVAL);
+		}
+		break;
+
+	case OF_RECONFIG_CHANGE_REMOVE:
+		/* find our device by node */
+		pdev = of_find_device_by_node(rd->dn);
+		if (pdev == NULL)
+			return NOTIFY_OK;	/* no? not meant for us */
+
+		/* unregister takes one ref away */
+		of_platform_device_destroy(&pdev->dev, &children_left);
+
+		/* and put the reference of the find */
+		of_dev_put(pdev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block platform_of_notifier = {
+	.notifier_call = of_platform_notify,
+};
+
+void of_platform_register_reconfig_notifier(void)
+{
+	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
 #endif /* CONFIG_OF_ADDRESS */
diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
index c2b0627a2317..8a860f096c35 100644
--- a/include/linux/of_platform.h
+++ b/include/linux/of_platform.h
@@ -84,4 +84,10 @@ static inline int of_platform_populate(struct device_node *root,
 static inline void of_platform_depopulate(struct device *parent) { }
 #endif
 
+#ifdef CONFIG_OF_DYNAMIC
+extern void of_platform_register_reconfig_notifier(void);
+#else
+static inline void of_platform_register_reconfig_notifier(void) { }
+#endif
+
 #endif	/* _LINUX_OF_PLATFORM_H */

From 7518b5890d8ac366faa2326ce2356ef6392ce63d Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:35:58 +0200
Subject: [PATCH 27/42] of/overlay: Introduce DT overlay support

Overlays are a method to dynamically modify part of the kernel's
device tree with dynamically loaded data. Add the core functionality to
parse, apply and remove an overlay changeset. The core functionality
takes care of managing the overlay data format and performing the add
and remove. Drivers are expected to use the overlay functionality to
support custom expansion busses commonly found on consumer development
boards like the BeagleBone or Raspberry Pi.

The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low
level work of modifying the devicetree.

Documentation about internal and APIs is provided in
	Documentation/devicetree/overlay-notes.txt

v2:
- Switch from __of_node_alloc() to __of_node_dup()
- Documentation fixups
- Remove 2-pass processing of properties
- Remove separate ov_lock; just use the DT mutex.
v1:
- Drop delete capability using '-' prefix. The '-' prefixed names
are valid properties and nodes and there is no need for it just yet.
- Do not update special properties - name & phandle ones.
- Change order of node attachment, so that the special property update
works.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 Documentation/devicetree/overlay-notes.txt | 133 +++++
 drivers/of/Kconfig                         |   7 +
 drivers/of/Makefile                        |   1 +
 drivers/of/overlay.c                       | 562 +++++++++++++++++++++
 include/linux/of.h                         |  31 ++
 5 files changed, 734 insertions(+)
 create mode 100644 Documentation/devicetree/overlay-notes.txt
 create mode 100644 drivers/of/overlay.c

diff --git a/Documentation/devicetree/overlay-notes.txt b/Documentation/devicetree/overlay-notes.txt
new file mode 100644
index 000000000000..30ae758e3eef
--- /dev/null
+++ b/Documentation/devicetree/overlay-notes.txt
@@ -0,0 +1,133 @@
+Device Tree Overlay Notes
+-------------------------
+
+This document describes the implementation of the in-kernel
+device tree overlay functionality residing in drivers/of/overlay.c and is a
+companion document to Documentation/devicetree/dt-object-internal.txt[1] &
+Documentation/devicetree/dynamic-resolution-notes.txt[2]
+
+How overlays work
+-----------------
+
+A Device Tree's overlay purpose is to modify the kernel's live tree, and
+have the modification affecting the state of the the kernel in a way that
+is reflecting the changes.
+Since the kernel mainly deals with devices, any new device node that result
+in an active device should have it created while if the device node is either
+disabled or removed all together, the affected device should be deregistered.
+
+Lets take an example where we have a foo board with the following base tree
+which is taken from [1].
+
+---- foo.dts -----------------------------------------------------------------
+	/* FOO platform */
+	/ {
+		compatible = "corp,foo";
+
+		/* shared resources */
+		res: res {
+		};
+
+		/* On chip peripherals */
+		ocp: ocp {
+			/* peripherals that are always instantiated */
+			peripheral1 { ... };
+		}
+	};
+---- foo.dts -----------------------------------------------------------------
+
+The overlay bar.dts, when loaded (and resolved as described in [2]) should
+
+---- bar.dts -----------------------------------------------------------------
+/plugin/;	/* allow undefined label references and record them */
+/ {
+	....	/* various properties for loader use; i.e. part id etc. */
+	fragment@0 {
+		target = <&ocp>;
+		__overlay__ {
+			/* bar peripheral */
+			bar {
+				compatible = "corp,bar";
+				... /* various properties and child nodes */
+			}
+		};
+	};
+};
+---- bar.dts -----------------------------------------------------------------
+
+result in foo+bar.dts
+
+---- foo+bar.dts -------------------------------------------------------------
+	/* FOO platform + bar peripheral */
+	/ {
+		compatible = "corp,foo";
+
+		/* shared resources */
+		res: res {
+		};
+
+		/* On chip peripherals */
+		ocp: ocp {
+			/* peripherals that are always instantiated */
+			peripheral1 { ... };
+
+			/* bar peripheral */
+			bar {
+				compatible = "corp,bar";
+				... /* various properties and child nodes */
+			}
+		}
+	};
+---- foo+bar.dts -------------------------------------------------------------
+
+As a result of the the overlay, a new device node (bar) has been created
+so a bar platform device will be registered and if a matching device driver
+is loaded the device will be created as expected.
+
+Overlay in-kernel API
+--------------------------------
+
+The API is quite easy to use.
+
+1. Call of_overlay_create() to create and apply an overlay. The return value
+is a cookie identifying this overlay.
+
+2. Call of_overlay_destroy() to remove and cleanup the overlay previously
+created via the call to of_overlay_create(). Removal of an overlay that
+is stacked by another will not be permitted.
+
+Finally, if you need to remove all overlays in one-go, just call
+of_overlay_destroy_all() which will remove every single one in the correct
+order.
+
+Overlay DTS Format
+------------------
+
+The DTS of an overlay should have the following format:
+
+{
+	/* ignored properties by the overlay */
+
+	fragment@0 {	/* first child node */
+
+		target=<phandle>;	/* phandle target of the overlay */
+	or
+		target-path="/path";	/* target path of the overlay */
+
+		__overlay__ {
+			property-a;	/* add property-a to the target */
+			node-a {	/* add to an existing, or create a node-a */
+				...
+			};
+		};
+	}
+	fragment@1 {	/* second child node */
+		...
+	};
+	/* more fragments follow */
+}
+
+Using the non-phandle based target method allows one to use a base DT which does
+not contain a __symbols__ node, i.e. it was not compiled with the -@ option.
+The __symbols__ node is only required for the target=<phandle> method, since it
+contains the information required to map from a phandle to a tree location.
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index fbe8f8d418f7..18b2e2539f84 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -84,4 +84,11 @@ config OF_RESERVED_MEM
 config OF_RESOLVE
 	bool
 
+config OF_OVERLAY
+	bool
+	depends on OF
+	select OF_DYNAMIC
+	select OF_DEVICE
+	select OF_RESOLVE
+
 endmenu # OF
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index d90553fcd37f..7563f36c71db 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o
 obj-$(CONFIG_OF_MTD)	+= of_mtd.o
 obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
 obj-$(CONFIG_OF_RESOLVE)  += resolver.o
+obj-$(CONFIG_OF_OVERLAY) += overlay.o
 
 CFLAGS_fdt.o = -I$(src)/../../scripts/dtc/libfdt
 CFLAGS_fdt_address.o = -I$(src)/../../scripts/dtc/libfdt
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
new file mode 100644
index 000000000000..ea63fbd228ed
--- /dev/null
+++ b/drivers/of/overlay.c
@@ -0,0 +1,562 @@
+/*
+ * Functions for working with device tree overlays
+ *
+ * Copyright (C) 2012 Pantelis Antoniou <panto@antoniou-consulting.com>
+ * Copyright (C) 2012 Texas Instruments Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+#undef DEBUG
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+
+#include "of_private.h"
+
+/**
+ * struct of_overlay_info - Holds a single overlay info
+ * @target:	target of the overlay operation
+ * @overlay:	pointer to the overlay contents node
+ *
+ * Holds a single overlay state, including all the overlay logs &
+ * records.
+ */
+struct of_overlay_info {
+	struct device_node *target;
+	struct device_node *overlay;
+};
+
+/**
+ * struct of_overlay - Holds a complete overlay transaction
+ * @node:	List on which we are located
+ * @count:	Count of ovinfo structures
+ * @ovinfo_tab:	Overlay info table (count sized)
+ * @cset:	Changeset to be used
+ *
+ * Holds a complete overlay transaction
+ */
+struct of_overlay {
+	int id;
+	struct list_head node;
+	int count;
+	struct of_overlay_info *ovinfo_tab;
+	struct of_changeset cset;
+};
+
+static int of_overlay_apply_one(struct of_overlay *ov,
+		struct device_node *target, const struct device_node *overlay);
+
+static int of_overlay_apply_single_property(struct of_overlay *ov,
+		struct device_node *target, struct property *prop)
+{
+	struct property *propn, *tprop;
+
+	/* NOTE: Multiple changes of single properties not supported */
+	tprop = of_find_property(target, prop->name, NULL);
+
+	/* special properties are not meant to be updated (silent NOP) */
+	if (of_prop_cmp(prop->name, "name") == 0 ||
+	    of_prop_cmp(prop->name, "phandle") == 0 ||
+	    of_prop_cmp(prop->name, "linux,phandle") == 0)
+		return 0;
+
+	propn = __of_prop_dup(prop, GFP_KERNEL);
+	if (propn == NULL)
+		return -ENOMEM;
+
+	/* not found? add */
+	if (tprop == NULL)
+		return of_changeset_add_property(&ov->cset, target, propn);
+
+	/* found? update */
+	return of_changeset_update_property(&ov->cset, target, propn);
+}
+
+static int of_overlay_apply_single_device_node(struct of_overlay *ov,
+		struct device_node *target, struct device_node *child)
+{
+	const char *cname;
+	struct device_node *tchild, *grandchild;
+	int ret = 0;
+
+	cname = kbasename(child->full_name);
+	if (cname == NULL)
+		return -ENOMEM;
+
+	/* NOTE: Multiple mods of created nodes not supported */
+	tchild = of_get_child_by_name(target, cname);
+	if (tchild != NULL) {
+		/* apply overlay recursively */
+		ret = of_overlay_apply_one(ov, tchild, child);
+		of_node_put(tchild);
+	} else {
+		/* create empty tree as a target */
+		tchild = __of_node_dup(child, "%s/%s", target->full_name, cname);
+		if (!tchild)
+			return -ENOMEM;
+
+		/* point to parent */
+		tchild->parent = target;
+
+		ret = of_changeset_attach_node(&ov->cset, tchild);
+		if (ret)
+			return ret;
+
+		ret = of_overlay_apply_one(ov, tchild, child);
+		if (ret)
+			return ret;
+
+		/* The properties are already copied, now do the child nodes */
+		for_each_child_of_node(child, grandchild) {
+			ret = of_overlay_apply_single_device_node(ov, tchild, grandchild);
+			if (ret) {
+				pr_err("%s: Failed to apply single node @%s/%s\n",
+					__func__, tchild->full_name,
+					grandchild->name);
+				return ret;
+			}
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * Apply a single overlay node recursively.
+ *
+ * Note that the in case of an error the target node is left
+ * in a inconsistent state. Error recovery should be performed
+ * by using the changeset.
+ */
+static int of_overlay_apply_one(struct of_overlay *ov,
+		struct device_node *target, const struct device_node *overlay)
+{
+	struct device_node *child;
+	struct property *prop;
+	int ret;
+
+	for_each_property_of_node(overlay, prop) {
+		ret = of_overlay_apply_single_property(ov, target, prop);
+		if (ret) {
+			pr_err("%s: Failed to apply prop @%s/%s\n",
+				__func__, target->full_name, prop->name);
+			return ret;
+		}
+	}
+
+	for_each_child_of_node(overlay, child) {
+		ret = of_overlay_apply_single_device_node(ov, target, child);
+		if (ret != 0) {
+			pr_err("%s: Failed to apply single node @%s/%s\n",
+					__func__, target->full_name,
+					child->name);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * of_overlay_apply() - Apply @count overlays pointed at by @ovinfo_tab
+ * @ov:		Overlay to apply
+ *
+ * Applies the overlays given, while handling all error conditions
+ * appropriately. Either the operation succeeds, or if it fails the
+ * live tree is reverted to the state before the attempt.
+ * Returns 0, or an error if the overlay attempt failed.
+ */
+static int of_overlay_apply(struct of_overlay *ov)
+{
+	int i, err;
+
+	/* first we apply the overlays atomically */
+	for (i = 0; i < ov->count; i++) {
+		struct of_overlay_info *ovinfo = &ov->ovinfo_tab[i];
+
+		err = of_overlay_apply_one(ov, ovinfo->target, ovinfo->overlay);
+		if (err != 0) {
+			pr_err("%s: overlay failed '%s'\n",
+				__func__, ovinfo->target->full_name);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Find the target node using a number of different strategies
+ * in order of preference
+ *
+ * "target" property containing the phandle of the target
+ * "target-path" property containing the path of the target
+ */
+static struct device_node *find_target_node(struct device_node *info_node)
+{
+	const char *path;
+	u32 val;
+	int ret;
+
+	/* first try to go by using the target as a phandle */
+	ret = of_property_read_u32(info_node, "target", &val);
+	if (ret == 0)
+		return of_find_node_by_phandle(val);
+
+	/* now try to locate by path */
+	ret = of_property_read_string(info_node, "target-path", &path);
+	if (ret == 0)
+		return of_find_node_by_path(path);
+
+	pr_err("%s: Failed to find target for node %p (%s)\n", __func__,
+		info_node, info_node->name);
+
+	return NULL;
+}
+
+/**
+ * of_fill_overlay_info() - Fill an overlay info structure
+ * @ov		Overlay to fill
+ * @info_node:	Device node containing the overlay
+ * @ovinfo:	Pointer to the overlay info structure to fill
+ *
+ * Fills an overlay info structure with the overlay information
+ * from a device node. This device node must have a target property
+ * which contains a phandle of the overlay target node, and an
+ * __overlay__ child node which has the overlay contents.
+ * Both ovinfo->target & ovinfo->overlay have their references taken.
+ *
+ * Returns 0 on success, or a negative error value.
+ */
+static int of_fill_overlay_info(struct of_overlay *ov,
+		struct device_node *info_node, struct of_overlay_info *ovinfo)
+{
+	ovinfo->overlay = of_get_child_by_name(info_node, "__overlay__");
+	if (ovinfo->overlay == NULL)
+		goto err_fail;
+
+	ovinfo->target = find_target_node(info_node);
+	if (ovinfo->target == NULL)
+		goto err_fail;
+
+	return 0;
+
+err_fail:
+	of_node_put(ovinfo->target);
+	of_node_put(ovinfo->overlay);
+
+	memset(ovinfo, 0, sizeof(*ovinfo));
+	return -EINVAL;
+}
+
+/**
+ * of_build_overlay_info() - Build an overlay info array
+ * @ov		Overlay to build
+ * @tree:	Device node containing all the overlays
+ *
+ * Helper function that given a tree containing overlay information,
+ * allocates and builds an overlay info array containing it, ready
+ * for use using of_overlay_apply.
+ *
+ * Returns 0 on success with the @cntp @ovinfop pointers valid,
+ * while on error a negative error value is returned.
+ */
+static int of_build_overlay_info(struct of_overlay *ov,
+		struct device_node *tree)
+{
+	struct device_node *node;
+	struct of_overlay_info *ovinfo;
+	int cnt, err;
+
+	/* worst case; every child is a node */
+	cnt = 0;
+	for_each_child_of_node(tree, node)
+		cnt++;
+
+	ovinfo = kcalloc(cnt, sizeof(*ovinfo), GFP_KERNEL);
+	if (ovinfo == NULL)
+		return -ENOMEM;
+
+	cnt = 0;
+	for_each_child_of_node(tree, node) {
+		memset(&ovinfo[cnt], 0, sizeof(*ovinfo));
+		err = of_fill_overlay_info(ov, node, &ovinfo[cnt]);
+		if (err == 0)
+			cnt++;
+	}
+
+	/* if nothing filled, return error */
+	if (cnt == 0) {
+		kfree(ovinfo);
+		return -ENODEV;
+	}
+
+	ov->count = cnt;
+	ov->ovinfo_tab = ovinfo;
+
+	return 0;
+}
+
+/**
+ * of_free_overlay_info() - Free an overlay info array
+ * @ov		Overlay to free the overlay info from
+ * @ovinfo_tab:	Array of overlay_info's to free
+ *
+ * Releases the memory of a previously allocated ovinfo array
+ * by of_build_overlay_info.
+ * Returns 0, or an error if the arguments are bogus.
+ */
+static int of_free_overlay_info(struct of_overlay *ov)
+{
+	struct of_overlay_info *ovinfo;
+	int i;
+
+	/* do it in reverse */
+	for (i = ov->count - 1; i >= 0; i--) {
+		ovinfo = &ov->ovinfo_tab[i];
+
+		of_node_put(ovinfo->target);
+		of_node_put(ovinfo->overlay);
+	}
+	kfree(ov->ovinfo_tab);
+
+	return 0;
+}
+
+static LIST_HEAD(ov_list);
+static DEFINE_IDR(ov_idr);
+
+/**
+ * of_overlay_create() - Create and apply an overlay
+ * @tree:	Device node containing all the overlays
+ *
+ * Creates and applies an overlay while also keeping track
+ * of the overlay in a list. This list can be used to prevent
+ * illegal overlay removals.
+ *
+ * Returns the id of the created overlay, or an negative error number
+ */
+int of_overlay_create(struct device_node *tree)
+{
+	struct of_overlay *ov;
+	int err, id;
+
+	/* allocate the overlay structure */
+	ov = kzalloc(sizeof(*ov), GFP_KERNEL);
+	if (ov == NULL)
+		return -ENOMEM;
+	ov->id = -1;
+
+	INIT_LIST_HEAD(&ov->node);
+
+	of_changeset_init(&ov->cset);
+
+	mutex_lock(&of_mutex);
+
+	id = idr_alloc(&ov_idr, ov, 0, 0, GFP_KERNEL);
+	if (id < 0) {
+		pr_err("%s: idr_alloc() failed for tree@%s\n",
+				__func__, tree->full_name);
+		err = id;
+		goto err_destroy_trans;
+	}
+	ov->id = id;
+
+	/* build the overlay info structures */
+	err = of_build_overlay_info(ov, tree);
+	if (err) {
+		pr_err("%s: of_build_overlay_info() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_free_idr;
+	}
+
+	/* apply the overlay */
+	err = of_overlay_apply(ov);
+	if (err) {
+		pr_err("%s: of_overlay_apply() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_abort_trans;
+	}
+
+	/* apply the changeset */
+	err = of_changeset_apply(&ov->cset);
+	if (err) {
+		pr_err("%s: of_changeset_apply() failed for tree@%s\n",
+				__func__, tree->full_name);
+		goto err_revert_overlay;
+	}
+
+	/* add to the tail of the overlay list */
+	list_add_tail(&ov->node, &ov_list);
+
+	mutex_unlock(&of_mutex);
+
+	return id;
+
+err_revert_overlay:
+err_abort_trans:
+	of_free_overlay_info(ov);
+err_free_idr:
+	idr_remove(&ov_idr, ov->id);
+err_destroy_trans:
+	of_changeset_destroy(&ov->cset);
+	kfree(ov);
+	mutex_unlock(&of_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_overlay_create);
+
+/* check whether the given node, lies under the given tree */
+static int overlay_subtree_check(struct device_node *tree,
+		struct device_node *dn)
+{
+	struct device_node *child;
+
+	/* match? */
+	if (tree == dn)
+		return 1;
+
+	for_each_child_of_node(tree, child) {
+		if (overlay_subtree_check(child, dn))
+			return 1;
+	}
+
+	return 0;
+}
+
+/* check whether this overlay is the topmost */
+static int overlay_is_topmost(struct of_overlay *ov, struct device_node *dn)
+{
+	struct of_overlay *ovt;
+	struct of_changeset_entry *ce;
+
+	list_for_each_entry_reverse(ovt, &ov_list, node) {
+		/* if we hit ourselves, we're done */
+		if (ovt == ov)
+			break;
+
+		/* check against each subtree affected by this overlay */
+		list_for_each_entry(ce, &ovt->cset.entries, node) {
+			if (overlay_subtree_check(ce->np, dn)) {
+				pr_err("%s: #%d clashes #%d @%s\n",
+					__func__, ov->id, ovt->id,
+					dn->full_name);
+				return 0;
+			}
+		}
+	}
+
+	/* overlay is topmost */
+	return 1;
+}
+
+/*
+ * We can safely remove the overlay only if it's the top-most one.
+ * Newly applied overlays are inserted at the tail of the overlay list,
+ * so a top most overlay is the one that is closest to the tail.
+ *
+ * The topmost check is done by exploiting this property. For each
+ * affected device node in the log list we check if this overlay is
+ * the one closest to the tail. If another overlay has affected this
+ * device node and is closest to the tail, then removal is not permited.
+ */
+static int overlay_removal_is_ok(struct of_overlay *ov)
+{
+	struct of_changeset_entry *ce;
+
+	list_for_each_entry(ce, &ov->cset.entries, node) {
+		if (!overlay_is_topmost(ov, ce->np)) {
+			pr_err("%s: overlay #%d is not topmost\n",
+					__func__, ov->id);
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+/**
+ * of_overlay_destroy() - Removes an overlay
+ * @id:	Overlay id number returned by a previous call to of_overlay_create
+ *
+ * Removes an overlay if it is permissible.
+ *
+ * Returns 0 on success, or an negative error number
+ */
+int of_overlay_destroy(int id)
+{
+	struct of_overlay *ov;
+	int err;
+
+	mutex_lock(&of_mutex);
+
+	ov = idr_find(&ov_idr, id);
+	if (ov == NULL) {
+		err = -ENODEV;
+		pr_err("%s: Could not find overlay #%d\n",
+				__func__, id);
+		goto out;
+	}
+
+	/* check whether the overlay is safe to remove */
+	if (!overlay_removal_is_ok(ov)) {
+		err = -EBUSY;
+		pr_err("%s: removal check failed for overlay #%d\n",
+				__func__, id);
+		goto out;
+	}
+
+
+	list_del(&ov->node);
+	of_changeset_revert(&ov->cset);
+	of_free_overlay_info(ov);
+	idr_remove(&ov_idr, id);
+	of_changeset_destroy(&ov->cset);
+	kfree(ov);
+
+	err = 0;
+
+out:
+	mutex_unlock(&of_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_overlay_destroy);
+
+/**
+ * of_overlay_destroy_all() - Removes all overlays from the system
+ *
+ * Removes all overlays from the system in the correct order.
+ *
+ * Returns 0 on success, or an negative error number
+ */
+int of_overlay_destroy_all(void)
+{
+	struct of_overlay *ov, *ovn;
+
+	mutex_lock(&of_mutex);
+
+	/* the tail of list is guaranteed to be safe to remove */
+	list_for_each_entry_safe_reverse(ov, ovn, &ov_list, node) {
+		list_del(&ov->node);
+		of_changeset_revert(&ov->cset);
+		of_free_overlay_info(ov);
+		idr_remove(&ov_idr, ov->id);
+		kfree(ov);
+	}
+
+	mutex_unlock(&of_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_overlay_destroy_all);
diff --git a/include/linux/of.h b/include/linux/of.h
index fe1dec87fd68..aa01cf5852f8 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -23,6 +23,7 @@
 #include <linux/spinlock.h>
 #include <linux/topology.h>
 #include <linux/notifier.h>
+#include <linux/list.h>
 
 #include <asm/byteorder.h>
 #include <asm/errno.h>
@@ -957,4 +958,34 @@ static inline int of_reconfig_get_state_change(unsigned long action,
 /* CONFIG_OF_RESOLVE api */
 extern int of_resolve_phandles(struct device_node *tree);
 
+/**
+ * Overlay support
+ */
+
+#ifdef CONFIG_OF_OVERLAY
+
+/* ID based overlays; the API for external users */
+int of_overlay_create(struct device_node *tree);
+int of_overlay_destroy(int id);
+int of_overlay_destroy_all(void);
+
+#else
+
+static inline int of_overlay_create(struct device_node *tree)
+{
+	return -ENOTSUPP;
+}
+
+static inline int of_overlay_destroy(int id)
+{
+	return -ENOTSUPP;
+}
+
+static inline int of_overlay_destroy_all(void)
+{
+	return -ENOTSUPP;
+}
+
+#endif
+
 #endif /* _LINUX_OF_H */

From 177d271cf3171bb6826ee5189f67dc1f7d34f1da Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:35:59 +0200
Subject: [PATCH 28/42] of/overlay: Add overlay unittests

Add unittests for OF overlays.

It tests overlay device addition/removal and whether
the apply revert sequence is correct.

Changes since V1:
* Added local fixups entries.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 .../devicetree/bindings/unittest.txt          |  14 +
 drivers/of/unittest-data/testcases.dts        |  16 +
 drivers/of/unittest-data/tests-overlay.dtsi   | 180 +++++++
 drivers/of/unittest.c                         | 481 ++++++++++++++++++
 4 files changed, 691 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/unittest.txt
 create mode 100644 drivers/of/unittest-data/tests-overlay.dtsi

diff --git a/Documentation/devicetree/bindings/unittest.txt b/Documentation/devicetree/bindings/unittest.txt
new file mode 100644
index 000000000000..0f92a22fddfa
--- /dev/null
+++ b/Documentation/devicetree/bindings/unittest.txt
@@ -0,0 +1,14 @@
+* OF selftest platform device
+
+** selftest
+
+Required properties:
+- compatible: must be "selftest"
+
+All other properties are optional.
+
+Example:
+	selftest {
+		compatible = "selftest";
+		status = "okay";
+	};
diff --git a/drivers/of/unittest-data/testcases.dts b/drivers/of/unittest-data/testcases.dts
index b6bc41b2a185..12f7c3d649c8 100644
--- a/drivers/of/unittest-data/testcases.dts
+++ b/drivers/of/unittest-data/testcases.dts
@@ -13,6 +13,7 @@
 #include "tests-interrupts.dtsi"
 #include "tests-match.dtsi"
 #include "tests-platform.dtsi"
+#include "tests-overlay.dtsi"
 
 /*
  * phandle fixup data - generated by dtc patches that aren't upstream.
@@ -59,5 +60,20 @@
 		testcase-device2 {
 			interrupt-parent = <0x00000000>;
 		};
+		overlay2 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
+		overlay3 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
+		overlay4 {
+			fragment@0 {
+				target = <0x00000000>;
+			};
+		};
 	};
 }; };
diff --git a/drivers/of/unittest-data/tests-overlay.dtsi b/drivers/of/unittest-data/tests-overlay.dtsi
new file mode 100644
index 000000000000..75976da22b2e
--- /dev/null
+++ b/drivers/of/unittest-data/tests-overlay.dtsi
@@ -0,0 +1,180 @@
+
+/ {
+	testcase-data {
+		overlay-node {
+
+			/* test bus */
+			selftestbus: test-bus {
+				compatible = "simple-bus";
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				selftest100: test-selftest100 {
+					compatible = "selftest";
+					status = "okay";
+					reg = <100>;
+				};
+
+				selftest101: test-selftest101 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <101>;
+				};
+
+				selftest0: test-selftest0 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <0>;
+				};
+
+				selftest1: test-selftest1 {
+					compatible = "selftest";
+					status = "okay";
+					reg = <1>;
+				};
+
+				selftest2: test-selftest2 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <2>;
+				};
+
+				selftest3: test-selftest3 {
+					compatible = "selftest";
+					status = "okay";
+					reg = <3>;
+				};
+
+				selftest5: test-selftest5 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <5>;
+				};
+
+				selftest6: test-selftest6 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <6>;
+				};
+
+				selftest7: test-selftest7 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <7>;
+				};
+
+				selftest8: test-selftest8 {
+					compatible = "selftest";
+					status = "disabled";
+					reg = <8>;
+				};
+			};
+		};
+
+		/* test enable using absolute target path */
+		overlay0 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest0";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test disable using absolute target path */
+		overlay1 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest1";
+				__overlay__ {
+					status = "disabled";
+				};
+			};
+		};
+
+		/* test enable using label */
+		overlay2 {
+			fragment@0 {
+				target = <&selftest2>;
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test disable using label */
+		overlay3 {
+			fragment@0 {
+				target = <&selftest3>;
+				__overlay__ {
+					status = "disabled";
+				};
+			};
+		};
+
+		/* test insertion of a full node */
+		overlay4 {
+			fragment@0 {
+				target = <&selftestbus>;
+				__overlay__ {
+
+					/* suppress DTC warning */
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					test-selftest4 {
+						compatible = "selftest";
+						status = "okay";
+						reg = <4>;
+					};
+				};
+			};
+		};
+
+		/* test overlay apply revert */
+		overlay5 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest5";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test overlays application and removal in sequence */
+		overlay6 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest6";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+		overlay7 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest7";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+
+		/* test overlays application and removal in bad sequence */
+		overlay8 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest8";
+				__overlay__ {
+					status = "okay";
+				};
+			};
+		};
+		overlay9 {
+			fragment@0 {
+				target-path = "/testcase-data/overlay-node/test-bus/test-selftest8";
+				__overlay__ {
+					property-foo = "bar";
+				};
+			};
+		};
+
+	};
+};
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 1720b039cac7..cc0c5ec5d464 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -17,6 +17,8 @@
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
 
 #include "of_private.h"
 
@@ -933,6 +935,484 @@ static void selftest_data_remove(void)
 	}
 }
 
+#ifdef CONFIG_OF_OVERLAY
+
+static int selftest_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	if (np == NULL) {
+		dev_err(dev, "No OF data for device\n");
+		return -EINVAL;
+
+	}
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	return 0;
+}
+
+static int selftest_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
+	return 0;
+}
+
+static struct of_device_id selftest_match[] = {
+	{ .compatible = "selftest", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, altera_jtaguart_match);
+
+static struct platform_driver selftest_driver = {
+	.probe			= selftest_probe,
+	.remove			= selftest_remove,
+	.driver = {
+		.name		= "selftest",
+		.owner		= THIS_MODULE,
+		.of_match_table	= of_match_ptr(selftest_match),
+	},
+};
+
+/* get the platform device instantiated at the path */
+static struct platform_device *of_path_to_platform_device(const char *path)
+{
+	struct device_node *np;
+	struct platform_device *pdev;
+
+	np = of_find_node_by_path(path);
+	if (np == NULL)
+		return NULL;
+
+	pdev = of_find_device_by_node(np);
+	of_node_put(np);
+
+	return pdev;
+}
+
+/* find out if a platform device exists at that path */
+static int of_path_platform_device_exists(const char *path)
+{
+	struct platform_device *pdev;
+
+	pdev = of_path_to_platform_device(path);
+	platform_device_put(pdev);
+	return pdev != NULL;
+}
+
+static const char *selftest_path(int nr)
+{
+	static char buf[256];
+
+	snprintf(buf, sizeof(buf) - 1,
+		"/testcase-data/overlay-node/test-bus/test-selftest%d", nr);
+	buf[sizeof(buf) - 1] = '\0';
+
+	return buf;
+}
+
+static const char *overlay_path(int nr)
+{
+	static char buf[256];
+
+	snprintf(buf, sizeof(buf) - 1,
+		"/testcase-data/overlay%d", nr);
+	buf[sizeof(buf) - 1] = '\0';
+
+	return buf;
+}
+
+static const char *bus_path = "/testcase-data/overlay-node/test-bus";
+
+static int of_selftest_apply_overlay(int selftest_nr, int overlay_nr,
+		int *overlay_id)
+{
+	struct device_node *np = NULL;
+	int ret, id = -1;
+
+	np = of_find_node_by_path(overlay_path(overlay_nr));
+	if (np == NULL) {
+		selftest(0, "could not find overlay node @\"%s\"\n",
+				overlay_path(overlay_nr));
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = of_overlay_create(np);
+	if (ret < 0) {
+		selftest(0, "could not create overlay from \"%s\"\n",
+				overlay_path(overlay_nr));
+		goto out;
+	}
+	id = ret;
+
+	ret = 0;
+
+out:
+	of_node_put(np);
+
+	if (overlay_id)
+		*overlay_id = id;
+
+	return ret;
+}
+
+/* apply an overlay while checking before and after states */
+static int of_selftest_apply_overlay_check(int overlay_nr, int selftest_nr,
+		int before, int after)
+{
+	int ret;
+
+	/* selftest device must not be in before state */
+	if (of_path_platform_device_exists(selftest_path(selftest_nr))
+			!= before) {
+		selftest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	ret = of_selftest_apply_overlay(overlay_nr, selftest_nr, NULL);
+	if (ret != 0) {
+		/* of_selftest_apply_overlay already called selftest() */
+		return ret;
+	}
+
+	/* selftest device must be to set to after state */
+	if (of_path_platform_device_exists(selftest_path(selftest_nr))
+			!= after) {
+		selftest(0, "overlay @\"%s\" failed to create @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr),
+				!after ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* apply an overlay and then revert it while checking before, after states */
+static int of_selftest_apply_revert_overlay_check(int overlay_nr,
+		int selftest_nr, int before, int after)
+{
+	int ret, ov_id;
+
+	/* selftest device must be in before state */
+	if (of_path_platform_device_exists(selftest_path(selftest_nr))
+			!= before) {
+		selftest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	/* apply the overlay */
+	ret = of_selftest_apply_overlay(overlay_nr, selftest_nr, &ov_id);
+	if (ret != 0) {
+		/* of_selftest_apply_overlay already called selftest() */
+		return ret;
+	}
+
+	/* selftest device must be in after state */
+	if (of_path_platform_device_exists(selftest_path(selftest_nr))
+			!= after) {
+		selftest(0, "overlay @\"%s\" failed to create @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr),
+				!after ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	ret = of_overlay_destroy(ov_id);
+	if (ret != 0) {
+		selftest(0, "overlay @\"%s\" failed to be destroyed @\"%s\"\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr));
+		return ret;
+	}
+
+	/* selftest device must be again in before state */
+	if (of_path_platform_device_exists(selftest_path(selftest_nr))
+			!= before) {
+		selftest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+				overlay_path(overlay_nr),
+				selftest_path(selftest_nr),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* test activation of device */
+static void of_selftest_overlay_0(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_selftest_apply_overlay_check(0, 0, 0, 1);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 0);
+}
+
+/* test deactivation of device */
+static void of_selftest_overlay_1(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_selftest_apply_overlay_check(1, 1, 1, 0);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 1);
+}
+
+/* test activation of device */
+static void of_selftest_overlay_2(void)
+{
+	int ret;
+
+	/* device should enable */
+	ret = of_selftest_apply_overlay_check(2, 2, 0, 1);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 2);
+}
+
+/* test deactivation of device */
+static void of_selftest_overlay_3(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_selftest_apply_overlay_check(3, 3, 1, 0);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 3);
+}
+
+/* test activation of a full device node */
+static void of_selftest_overlay_4(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_selftest_apply_overlay_check(4, 4, 0, 1);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 4);
+}
+
+/* test overlay apply/revert sequence */
+static void of_selftest_overlay_5(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_selftest_apply_revert_overlay_check(5, 5, 0, 1);
+	if (ret != 0)
+		return;
+
+	selftest(1, "overlay test %d passed\n", 5);
+}
+
+/* test overlay application in sequence */
+static void of_selftest_overlay_6(void)
+{
+	struct device_node *np;
+	int ret, i, ov_id[2];
+	int overlay_nr = 6, selftest_nr = 6;
+	int before = 0, after = 1;
+
+	/* selftest device must be in before state */
+	for (i = 0; i < 2; i++) {
+		if (of_path_platform_device_exists(
+					selftest_path(selftest_nr + i))
+				!= before) {
+			selftest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					selftest_path(selftest_nr + i),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	/* apply the overlays */
+	for (i = 0; i < 2; i++) {
+
+		np = of_find_node_by_path(overlay_path(overlay_nr + i));
+		if (np == NULL) {
+			selftest(0, "could not find overlay node @\"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+
+		ret = of_overlay_create(np);
+		if (ret < 0)  {
+			selftest(0, "could not create overlay from \"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+		ov_id[i] = ret;
+	}
+
+	for (i = 0; i < 2; i++) {
+		/* selftest device must be in after state */
+		if (of_path_platform_device_exists(
+					selftest_path(selftest_nr + i))
+				!= after) {
+			selftest(0, "overlay @\"%s\" failed @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					selftest_path(selftest_nr + i),
+					!after ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	for (i = 1; i >= 0; i--) {
+		ret = of_overlay_destroy(ov_id[i]);
+		if (ret != 0) {
+			selftest(0, "overlay @\"%s\" failed destroy @\"%s\"\n",
+					overlay_path(overlay_nr + i),
+					selftest_path(selftest_nr + i));
+			return;
+		}
+	}
+
+	for (i = 0; i < 2; i++) {
+		/* selftest device must be again in before state */
+		if (of_path_platform_device_exists(
+					selftest_path(selftest_nr + i))
+				!= before) {
+			selftest(0, "overlay @\"%s\" with device @\"%s\" %s\n",
+					overlay_path(overlay_nr + i),
+					selftest_path(selftest_nr + i),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	selftest(1, "overlay test %d passed\n", 6);
+}
+
+/* test overlay application in sequence */
+static void of_selftest_overlay_8(void)
+{
+	struct device_node *np;
+	int ret, i, ov_id[2];
+	int overlay_nr = 8, selftest_nr = 8;
+
+	/* we don't care about device state in this test */
+
+	/* apply the overlays */
+	for (i = 0; i < 2; i++) {
+
+		np = of_find_node_by_path(overlay_path(overlay_nr + i));
+		if (np == NULL) {
+			selftest(0, "could not find overlay node @\"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+
+		ret = of_overlay_create(np);
+		if (ret < 0)  {
+			selftest(0, "could not create overlay from \"%s\"\n",
+					overlay_path(overlay_nr + i));
+			return;
+		}
+		ov_id[i] = ret;
+	}
+
+	/* now try to remove first overlay (it should fail) */
+	ret = of_overlay_destroy(ov_id[0]);
+	if (ret == 0) {
+		selftest(0, "overlay @\"%s\" was destroyed @\"%s\"\n",
+				overlay_path(overlay_nr + 0),
+				selftest_path(selftest_nr));
+		return;
+	}
+
+	/* removing them in order should work */
+	for (i = 1; i >= 0; i--) {
+		ret = of_overlay_destroy(ov_id[i]);
+		if (ret != 0) {
+			selftest(0, "overlay @\"%s\" not destroyed @\"%s\"\n",
+					overlay_path(overlay_nr + i),
+					selftest_path(selftest_nr));
+			return;
+		}
+	}
+
+	selftest(1, "overlay test %d passed\n", 8);
+}
+
+static void __init of_selftest_overlay(void)
+{
+	struct device_node *bus_np = NULL;
+	int ret;
+
+	ret = platform_driver_register(&selftest_driver);
+	if (ret != 0) {
+		selftest(0, "could not register selftest driver\n");
+		goto out;
+	}
+
+	bus_np = of_find_node_by_path(bus_path);
+	if (bus_np == NULL) {
+		selftest(0, "could not find bus_path \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	ret = of_platform_populate(bus_np, of_default_bus_match_table,
+			NULL, NULL);
+	if (ret != 0) {
+		selftest(0, "could not populate bus @ \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	if (!of_path_platform_device_exists(selftest_path(100))) {
+		selftest(0, "could not find selftest0 @ \"%s\"\n",
+				selftest_path(100));
+		goto out;
+	}
+
+	if (of_path_platform_device_exists(selftest_path(101))) {
+		selftest(0, "selftest1 @ \"%s\" should not exist\n",
+				selftest_path(101));
+		goto out;
+	}
+
+	selftest(1, "basic infrastructure of overlays passed");
+
+	/* tests in sequence */
+	of_selftest_overlay_0();
+	of_selftest_overlay_1();
+	of_selftest_overlay_2();
+	of_selftest_overlay_3();
+	of_selftest_overlay_4();
+	of_selftest_overlay_5();
+	of_selftest_overlay_6();
+	of_selftest_overlay_8();
+
+out:
+	of_node_put(bus_np);
+}
+
+#else
+static inline void __init of_selftest_overlay(void) { }
+#endif
+
 static int __init of_selftest(void)
 {
 	struct device_node *np;
@@ -965,6 +1445,7 @@ static int __init of_selftest(void)
 	of_selftest_parse_interrupts_extended();
 	of_selftest_match_node();
 	of_selftest_platform_populate();
+	of_selftest_overlay();
 
 	/* removing selftest data from live tree */
 	selftest_data_remove();

From a430a3455f2c48995e06b359a82a1109a419e9ef Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:36:02 +0200
Subject: [PATCH 29/42] i2c/of: Factor out Devicetree registration code

Dynamically inserting i2c client device nodes requires the use
of a single device registration method. Factor out the loop body of
of_i2c_register_devices() so that it can be called for individual
device_nodes instead of for all the children of a node.

Note: The diff of this commit looks far more complicated than it
actually is due the indentation being changed for a large block of code.
When viewed using the diff -w flag to ignore whitespace changes it can
be seen that the change is actually quite simple.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Made new function static and removed changes to header]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
---
 drivers/i2c/i2c-core.c | 101 ++++++++++++++++++++++-------------------
 1 file changed, 54 insertions(+), 47 deletions(-)

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index f43b4e11647a..15ba6185dba5 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -49,6 +49,7 @@
 #include <linux/acpi.h>
 #include <linux/jump_label.h>
 #include <asm/uaccess.h>
+#include <linux/err.h>
 
 #include "i2c-core.h"
 
@@ -1368,9 +1369,59 @@ static void i2c_scan_static_board_info(struct i2c_adapter *adapter)
 /* OF support code */
 
 #if IS_ENABLED(CONFIG_OF)
+static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
+						 struct device_node *node)
+{
+	struct i2c_client *result;
+	struct i2c_board_info info = {};
+	struct dev_archdata dev_ad = {};
+	const __be32 *addr;
+	int len;
+
+	dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
+
+	if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
+		dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
+			node->full_name);
+		return ERR_PTR(-EINVAL);
+	}
+
+	addr = of_get_property(node, "reg", &len);
+	if (!addr || (len < sizeof(int))) {
+		dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
+			node->full_name);
+		return ERR_PTR(-EINVAL);
+	}
+
+	info.addr = be32_to_cpup(addr);
+	if (info.addr > (1 << 10) - 1) {
+		dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
+			info.addr, node->full_name);
+		return ERR_PTR(-EINVAL);
+	}
+
+	info.irq = irq_of_parse_and_map(node, 0);
+	info.of_node = of_node_get(node);
+	info.archdata = &dev_ad;
+
+	if (of_get_property(node, "wakeup-source", NULL))
+		info.flags |= I2C_CLIENT_WAKE;
+
+	request_module("%s%s", I2C_MODULE_PREFIX, info.type);
+
+	result = i2c_new_device(adap, &info);
+	if (result == NULL) {
+		dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
+			node->full_name);
+		of_node_put(node);
+		irq_dispose_mapping(info.irq);
+		return ERR_PTR(-EINVAL);
+	}
+	return result;
+}
+
 static void of_i2c_register_devices(struct i2c_adapter *adap)
 {
-	void *result;
 	struct device_node *node;
 
 	/* Only register child devices if the adapter has a node pointer set */
@@ -1379,52 +1430,8 @@ static void of_i2c_register_devices(struct i2c_adapter *adap)
 
 	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
 
-	for_each_available_child_of_node(adap->dev.of_node, node) {
-		struct i2c_board_info info = {};
-		struct dev_archdata dev_ad = {};
-		const __be32 *addr;
-		int len;
-
-		dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
-
-		if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
-			dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
-				node->full_name);
-			continue;
-		}
-
-		addr = of_get_property(node, "reg", &len);
-		if (!addr || (len < sizeof(int))) {
-			dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
-				node->full_name);
-			continue;
-		}
-
-		info.addr = be32_to_cpup(addr);
-		if (info.addr > (1 << 10) - 1) {
-			dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
-				info.addr, node->full_name);
-			continue;
-		}
-
-		info.irq = irq_of_parse_and_map(node, 0);
-		info.of_node = of_node_get(node);
-		info.archdata = &dev_ad;
-
-		if (of_get_property(node, "wakeup-source", NULL))
-			info.flags |= I2C_CLIENT_WAKE;
-
-		request_module("%s%s", I2C_MODULE_PREFIX, info.type);
-
-		result = i2c_new_device(adap, &info);
-		if (result == NULL) {
-			dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
-				node->full_name);
-			of_node_put(node);
-			irq_dispose_mapping(info.irq);
-			continue;
-		}
-	}
+	for_each_available_child_of_node(adap->dev.of_node, node)
+		of_i2c_register_device(adap, node);
 }
 
 static int of_dev_node_match(struct device *dev, void *data)

From ea7513bbc04170f1cbf42953187a4d8b731c71c4 Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:36:03 +0200
Subject: [PATCH 30/42] i2c/of: Add OF_RECONFIG notifier handler

CONFIG_OF_DYNAMIC enables runtime changes to the device tree which in
turn may trigger addition or removal of devices from Linux. Add an
OF_RECONFIG notifier handler to receive tree change events and to
creating or destroy i2c devices as required.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: clean up #ifdefs and drop unneeded error handling]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
---
 drivers/i2c/i2c-core.c | 52 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 15ba6185dba5..d8afd3f28ca4 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1951,6 +1951,52 @@ void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg)
 }
 EXPORT_SYMBOL(i2c_clients_command);
 
+#if IS_ENABLED(CONFIG_OF_DYNAMIC)
+static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
+			 void *arg)
+{
+	struct of_reconfig_data *rd = arg;
+	struct i2c_adapter *adap;
+	struct i2c_client *client;
+
+	switch (of_reconfig_get_state_change(action, rd)) {
+	case OF_RECONFIG_CHANGE_ADD:
+		adap = of_find_i2c_adapter_by_node(rd->dn->parent);
+		if (adap == NULL)
+			return NOTIFY_OK;	/* not for us */
+
+		client = of_i2c_register_device(adap, rd->dn);
+		put_device(&adap->dev);
+
+		if (IS_ERR(client)) {
+			pr_err("%s: failed to create for '%s'\n",
+					__func__, rd->dn->full_name);
+			return notifier_from_errno(PTR_ERR(client));
+		}
+		break;
+	case OF_RECONFIG_CHANGE_REMOVE:
+		/* find our device by node */
+		client = of_find_i2c_device_by_node(rd->dn);
+		if (client == NULL)
+			return NOTIFY_OK;	/* no? not meant for us */
+
+		/* unregister takes one ref away */
+		i2c_unregister_device(client);
+
+		/* and put the reference of the find */
+		put_device(&client->dev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+static struct notifier_block i2c_of_notifier = {
+	.notifier_call = of_i2c_notify,
+};
+#else
+extern struct notifier_block i2c_of_notifier;
+#endif /* CONFIG_OF_DYNAMIC */
+
 static int __init i2c_init(void)
 {
 	int retval;
@@ -1968,6 +2014,10 @@ static int __init i2c_init(void)
 	retval = i2c_add_driver(&dummy_driver);
 	if (retval)
 		goto class_err;
+
+	if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+		WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier));
+
 	return 0;
 
 class_err:
@@ -1981,6 +2031,8 @@ bus_err:
 
 static void __exit i2c_exit(void)
 {
+	if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+		WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier));
 	i2c_del_driver(&dummy_driver);
 #ifdef CONFIG_I2C_COMPAT
 	class_compat_unregister(i2c_adapter_compat_class);

From aff5e3f89a0b07e7edf9243f913378cc27e4110d Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Wed, 29 Oct 2014 10:40:37 +0200
Subject: [PATCH 31/42] spi/of: Create new device registration method and
 accessors

Dynamically inserting spi device nodes requires the use of a single
device registration method. Refactor the existing
of_register_spi_devices() to split out the core functionality for a
single device into a separate function; of_register_spi_device(). This
function will be used by the OF_DYNAMIC overlay code to make live
modifications to the tree.

Methods to lookup a device/master using a device node are added
as well, of_find_spi_master_by_node() & of_find_spi_device_by_node().

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely] Split patch into two pieces for clarity
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>
---
 drivers/spi/spi.c | 222 ++++++++++++++++++++++++----------------------
 1 file changed, 118 insertions(+), 104 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index ebcb33df2eb2..a3557c57d4f7 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1220,6 +1220,121 @@ err_init_queue:
 /*-------------------------------------------------------------------------*/
 
 #if defined(CONFIG_OF)
+static struct spi_device *
+of_register_spi_device(struct spi_master *master, struct device_node *nc)
+{
+	struct spi_device *spi;
+	int rc;
+	u32 value;
+
+	/* Alloc an spi_device */
+	spi = spi_alloc_device(master);
+	if (!spi) {
+		dev_err(&master->dev, "spi_device alloc error for %s\n",
+			nc->full_name);
+		rc = -ENOMEM;
+		goto err_out;
+	}
+
+	/* Select device driver */
+	rc = of_modalias_node(nc, spi->modalias,
+				sizeof(spi->modalias));
+	if (rc < 0) {
+		dev_err(&master->dev, "cannot find modalias for %s\n",
+			nc->full_name);
+		goto err_out;
+	}
+
+	/* Device address */
+	rc = of_property_read_u32(nc, "reg", &value);
+	if (rc) {
+		dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
+			nc->full_name, rc);
+		goto err_out;
+	}
+	spi->chip_select = value;
+
+	/* Mode (clock phase/polarity/etc.) */
+	if (of_find_property(nc, "spi-cpha", NULL))
+		spi->mode |= SPI_CPHA;
+	if (of_find_property(nc, "spi-cpol", NULL))
+		spi->mode |= SPI_CPOL;
+	if (of_find_property(nc, "spi-cs-high", NULL))
+		spi->mode |= SPI_CS_HIGH;
+	if (of_find_property(nc, "spi-3wire", NULL))
+		spi->mode |= SPI_3WIRE;
+	if (of_find_property(nc, "spi-lsb-first", NULL))
+		spi->mode |= SPI_LSB_FIRST;
+
+	/* Device DUAL/QUAD mode */
+	if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
+		switch (value) {
+		case 1:
+			break;
+		case 2:
+			spi->mode |= SPI_TX_DUAL;
+			break;
+		case 4:
+			spi->mode |= SPI_TX_QUAD;
+			break;
+		default:
+			dev_warn(&master->dev,
+				"spi-tx-bus-width %d not supported\n",
+				value);
+			break;
+		}
+	}
+
+	if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) {
+		switch (value) {
+		case 1:
+			break;
+		case 2:
+			spi->mode |= SPI_RX_DUAL;
+			break;
+		case 4:
+			spi->mode |= SPI_RX_QUAD;
+			break;
+		default:
+			dev_warn(&master->dev,
+				"spi-rx-bus-width %d not supported\n",
+				value);
+			break;
+		}
+	}
+
+	/* Device speed */
+	rc = of_property_read_u32(nc, "spi-max-frequency", &value);
+	if (rc) {
+		dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n",
+			nc->full_name, rc);
+		goto err_out;
+	}
+	spi->max_speed_hz = value;
+
+	/* IRQ */
+	spi->irq = irq_of_parse_and_map(nc, 0);
+
+	/* Store a pointer to the node in the device structure */
+	of_node_get(nc);
+	spi->dev.of_node = nc;
+
+	/* Register the new device */
+	request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias);
+	rc = spi_add_device(spi);
+	if (rc) {
+		dev_err(&master->dev, "spi_device register error %s\n",
+			nc->full_name);
+		goto err_out;
+	}
+
+	return spi;
+
+err_out:
+	spi_dev_put(spi);
+	return ERR_PTR(rc);
+}
+
 /**
  * of_register_spi_devices() - Register child devices onto the SPI bus
  * @master:	Pointer to spi_master device
@@ -1231,116 +1346,15 @@ static void of_register_spi_devices(struct spi_master *master)
 {
 	struct spi_device *spi;
 	struct device_node *nc;
-	int rc;
-	u32 value;
 
 	if (!master->dev.of_node)
 		return;
 
 	for_each_available_child_of_node(master->dev.of_node, nc) {
-		/* Alloc an spi_device */
-		spi = spi_alloc_device(master);
-		if (!spi) {
-			dev_err(&master->dev, "spi_device alloc error for %s\n",
+		spi = of_register_spi_device(master, nc);
+		if (IS_ERR(spi))
+			dev_warn(&master->dev, "Failed to create SPI device for %s\n",
 				nc->full_name);
-			spi_dev_put(spi);
-			continue;
-		}
-
-		/* Select device driver */
-		if (of_modalias_node(nc, spi->modalias,
-				     sizeof(spi->modalias)) < 0) {
-			dev_err(&master->dev, "cannot find modalias for %s\n",
-				nc->full_name);
-			spi_dev_put(spi);
-			continue;
-		}
-
-		/* Device address */
-		rc = of_property_read_u32(nc, "reg", &value);
-		if (rc) {
-			dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
-				nc->full_name, rc);
-			spi_dev_put(spi);
-			continue;
-		}
-		spi->chip_select = value;
-
-		/* Mode (clock phase/polarity/etc.) */
-		if (of_find_property(nc, "spi-cpha", NULL))
-			spi->mode |= SPI_CPHA;
-		if (of_find_property(nc, "spi-cpol", NULL))
-			spi->mode |= SPI_CPOL;
-		if (of_find_property(nc, "spi-cs-high", NULL))
-			spi->mode |= SPI_CS_HIGH;
-		if (of_find_property(nc, "spi-3wire", NULL))
-			spi->mode |= SPI_3WIRE;
-		if (of_find_property(nc, "spi-lsb-first", NULL))
-			spi->mode |= SPI_LSB_FIRST;
-
-		/* Device DUAL/QUAD mode */
-		if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
-			switch (value) {
-			case 1:
-				break;
-			case 2:
-				spi->mode |= SPI_TX_DUAL;
-				break;
-			case 4:
-				spi->mode |= SPI_TX_QUAD;
-				break;
-			default:
-				dev_warn(&master->dev,
-					 "spi-tx-bus-width %d not supported\n",
-					 value);
-				break;
-			}
-		}
-
-		if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) {
-			switch (value) {
-			case 1:
-				break;
-			case 2:
-				spi->mode |= SPI_RX_DUAL;
-				break;
-			case 4:
-				spi->mode |= SPI_RX_QUAD;
-				break;
-			default:
-				dev_warn(&master->dev,
-					 "spi-rx-bus-width %d not supported\n",
-					 value);
-				break;
-			}
-		}
-
-		/* Device speed */
-		rc = of_property_read_u32(nc, "spi-max-frequency", &value);
-		if (rc) {
-			dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n",
-				nc->full_name, rc);
-			spi_dev_put(spi);
-			continue;
-		}
-		spi->max_speed_hz = value;
-
-		/* IRQ */
-		spi->irq = irq_of_parse_and_map(nc, 0);
-
-		/* Store a pointer to the node in the device structure */
-		of_node_get(nc);
-		spi->dev.of_node = nc;
-
-		/* Register the new device */
-		request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias);
-		rc = spi_add_device(spi);
-		if (rc) {
-			dev_err(&master->dev, "spi_device register error %s\n",
-				nc->full_name);
-			spi_dev_put(spi);
-		}
-
 	}
 }
 #else

From ce79d54ae447d65117303ca9f61ffe9dcbc2465d Mon Sep 17 00:00:00 2001
From: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Date: Tue, 28 Oct 2014 22:36:05 +0200
Subject: [PATCH 32/42] spi/of: Add OF notifier handler

Add OF notifier handler needed for creating/destroying spi devices
according to dynamic runtime changes in the DT live tree. This code is
enabled when CONFIG_OF_DYNAMIC is selected.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: <linux-spi@vger.kernel.org>
---
 drivers/spi/spi.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index a3557c57d4f7..bf1cab0fad66 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2317,6 +2317,86 @@ EXPORT_SYMBOL_GPL(spi_write_then_read);
 
 /*-------------------------------------------------------------------------*/
 
+#if IS_ENABLED(CONFIG_OF_DYNAMIC)
+static int __spi_of_device_match(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+/* must call put_device() when done with returned spi_device device */
+static struct spi_device *of_find_spi_device_by_node(struct device_node *node)
+{
+	struct device *dev = bus_find_device(&spi_bus_type, NULL, node,
+						__spi_of_device_match);
+	return dev ? to_spi_device(dev) : NULL;
+}
+
+static int __spi_of_master_match(struct device *dev, const void *data)
+{
+	return dev->of_node == data;
+}
+
+/* the spi masters are not using spi_bus, so we find it with another way */
+static struct spi_master *of_find_spi_master_by_node(struct device_node *node)
+{
+	struct device *dev;
+
+	dev = class_find_device(&spi_master_class, NULL, node,
+				__spi_of_master_match);
+	if (!dev)
+		return NULL;
+
+	/* reference got in class_find_device */
+	return container_of(dev, struct spi_master, dev);
+}
+
+static int of_spi_notify(struct notifier_block *nb, unsigned long action,
+			 void *arg)
+{
+	struct of_reconfig_data *rd = arg;
+	struct spi_master *master;
+	struct spi_device *spi;
+
+	switch (of_reconfig_get_state_change(action, arg)) {
+	case OF_RECONFIG_CHANGE_ADD:
+		master = of_find_spi_master_by_node(rd->dn->parent);
+		if (master == NULL)
+			return NOTIFY_OK;	/* not for us */
+
+		spi = of_register_spi_device(master, rd->dn);
+		put_device(&master->dev);
+
+		if (IS_ERR(spi)) {
+			pr_err("%s: failed to create for '%s'\n",
+					__func__, rd->dn->full_name);
+			return notifier_from_errno(PTR_ERR(spi));
+		}
+		break;
+
+	case OF_RECONFIG_CHANGE_REMOVE:
+		/* find our device by node */
+		spi = of_find_spi_device_by_node(rd->dn);
+		if (spi == NULL)
+			return NOTIFY_OK;	/* no? not meant for us */
+
+		/* unregister takes one ref away */
+		spi_unregister_device(spi);
+
+		/* and put the reference of the find */
+		put_device(&spi->dev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block spi_of_notifier = {
+	.notifier_call = of_spi_notify,
+};
+#else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
+extern struct notifier_block spi_of_notifier;
+#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
+
 static int __init spi_init(void)
 {
 	int	status;
@@ -2334,6 +2414,10 @@ static int __init spi_init(void)
 	status = class_register(&spi_master_class);
 	if (status < 0)
 		goto err2;
+
+	if (IS_ENABLED(CONFIG_OF))
+		WARN_ON(of_reconfig_notifier_register(&spi_of_notifier));
+
 	return 0;
 
 err2:

From 65d473b8007b4ef9f2a5e52f39c52d2141dfd421 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Wed, 26 Nov 2014 15:19:43 +0000
Subject: [PATCH 33/42] of: remove select of non-existant OF_DEVICE config
 symbol

The OF_OVERLAY option selects OF_DEVICE, but OF_DEVICE was removed in
commit ba166e900b, "of: remove CONFIG_OF_DEVICE". Remove the unnecessary
select.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
---
 drivers/of/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 18b2e2539f84..b5e0c873d4e1 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -88,7 +88,6 @@ config OF_OVERLAY
 	bool
 	depends on OF
 	select OF_DYNAMIC
-	select OF_DEVICE
 	select OF_RESOLVE
 
 endmenu # OF

From e99010edb37f5d5bca6a4d4b78d74cddfc0fc5a4 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Fri, 21 Nov 2014 13:23:09 +0100
Subject: [PATCH 34/42] of: base, fix of_property_read_string_helper kernel-doc

It referenced of_property_read_string_util whereas the function name
is of_property_read_string_helper.

Introduced in a87fa1d81a9fb5e9adca9820e16008c40ad09f33 (of: Fix
overflow bug in string property parsing functions). Found out when
reviewing the stable 3.12 queue.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 2d5dfb8b2e65..99bc95e83d09 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1326,7 +1326,7 @@ int of_property_match_string(struct device_node *np, const char *propname,
 EXPORT_SYMBOL_GPL(of_property_match_string);
 
 /**
- * of_property_read_string_util() - Utility helper for parsing string properties
+ * of_property_read_string_helper() - Utility helper for parsing string properties
  * @np:		device node from which the property value is to be read.
  * @propname:	name of the property to be searched.
  * @out_strs:	output array of string pointers.

From a81a6c654bbe129af529d11b4763367af90d1152 Mon Sep 17 00:00:00 2001
From: Linus Walleij <linus.walleij@linaro.org>
Date: Mon, 12 May 2014 11:37:17 +0200
Subject: [PATCH 35/42] ARM: dt: fix up PL011 device tree bindings

Make the map match the reality, the current binding text is
nonsense:

- The clock required for the clocking of the serial port
  must come first and is not optional (as the driver will
  otherwise proceed to grab and use the apb_pclk as uartclk),
  and the apb_pclk that clocks the logic must come second
  as the code will retrieve the first clock by index,
  whereas the PrimeCell but will explicitly look for
  "apb_pclk" so this can be specified later, as it is
  looked up by name.

- The pin control state "default" is the only mandated
  state, the sleep state is entirely optional.

We also add an example to avoid further confusion.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 .../devicetree/bindings/serial/pl011.txt      | 28 +++++++++++++++++--
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/serial/pl011.txt b/Documentation/devicetree/bindings/serial/pl011.txt
index 5d2e840ae65c..52464918cfe2 100644
--- a/Documentation/devicetree/bindings/serial/pl011.txt
+++ b/Documentation/devicetree/bindings/serial/pl011.txt
@@ -6,12 +6,34 @@ Required properties:
 - interrupts: exactly one interrupt specifier
 
 Optional properties:
-- pinctrl: When present, must have one state named "sleep"
-	   and one state named "default"
-- clocks:  When present, must refer to exactly one clock named
+- pinctrl: When present, must have one state named "default",
+	   and may contain a second name named "sleep". The former
+	   state sets up pins for ordinary operation whereas
+	   the latter state will put the associated pins to sleep
+	   when the UART is unused
+- clocks:  When present, the first clock listed must correspond to
+	   the clock named UARTCLK on the IP block, i.e. the clock
+	   to the external serial line, whereas the second clock
+	   must correspond to the PCLK clocking the internal logic
+	   of the block. Just listing one clock (the first one) is
+	   deprecated.
+- clocks-names: When present, the first clock listed must be named
+	   "uartclk" and the second clock listed must be named
 	   "apb_pclk"
 - dmas:	   When present, may have one or two dma channels.
 	   The first one must be named "rx", the second one
 	   must be named "tx".
 
 See also bindings/arm/primecell.txt
+
+Example:
+
+uart@80120000 {
+	compatible = "arm,pl011", "arm,primecell";
+	reg = <0x80120000 0x1000>;
+	interrupts = <0 11 IRQ_TYPE_LEVEL_HIGH>;
+	dmas = <&dma 13 0 0x2>, <&dma 13 0 0x0>;
+	dma-names = "rx", "tx";
+	clocks = <&foo_clk>, <&bar_clk>;
+	clock-names = "uartclk", "apb_pclk";
+};

From 63ebecc03d2f18411da51a0981bd63818bbd0b54 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Thu, 27 Nov 2014 23:57:22 +0000
Subject: [PATCH 36/42] of: Remove unneeded and incorrect MODULE_DEVICE_TABLE

The unittest code has a MODULE_DEVICE_TABLE that isn't needed by any of
the unittests, and isn't even correct. Remove it.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
---
 drivers/of/unittest.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index cc0c5ec5d464..7a7ae07d592f 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -965,7 +965,6 @@ static struct of_device_id selftest_match[] = {
 	{ .compatible = "selftest", },
 	{},
 };
-MODULE_DEVICE_TABLE(of, altera_jtaguart_match);
 
 static struct platform_driver selftest_driver = {
 	.probe			= selftest_probe,

From 2a9d832cc9aae21ea827520fef635b6c49a06c6d Mon Sep 17 00:00:00 2001
From: Leif Lindholm <leif.lindholm@linaro.org>
Date: Thu, 27 Nov 2014 17:56:05 +0000
Subject: [PATCH 37/42] of: Add bindings for chosen node, stdout-path

Add a global binding for the chosen node.  Include a description of the
stdout-path, and an explicit statement on its extra options in the
context of a UART console.

Opening description stolen from www.devicetree.org, and part of the
remaining text provided by Mark Rutland.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
[grant.likely: remove reference to uart_parse_options]
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 Documentation/devicetree/bindings/chosen.txt | 46 ++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/chosen.txt

diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt
new file mode 100644
index 000000000000..ed838f453f7a
--- /dev/null
+++ b/Documentation/devicetree/bindings/chosen.txt
@@ -0,0 +1,46 @@
+The chosen node
+---------------
+
+The chosen node does not represent a real device, but serves as a place
+for passing data between firmware and the operating system, like boot
+arguments. Data in the chosen node does not represent the hardware.
+
+
+stdout-path property
+--------------------
+
+Device trees may specify the device to be used for boot console output
+with a stdout-path property under /chosen, as described in ePAPR, e.g.
+
+/ {
+	chosen {
+		stdout-path = "/serial@f00:115200";
+	};
+
+	serial@f00 {
+		compatible = "vendor,some-uart";
+		reg = <0xf00 0x10>;
+	};
+};
+
+If the character ":" is present in the value, this terminates the path.
+The meaning of any characters following the ":" is device-specific, and
+must be specified in the relevant binding documentation.
+
+For UART devices, the preferred binding is a string in the form:
+
+	<baud>{<parity>{<bits>{<flow>}}}
+
+where
+
+	baud	- baud rate in decimal
+	parity	- 'n' (none), 'o', (odd) or 'e' (even)
+	bits	- number of data bits
+	flow	- 'r' (rts)
+
+For example: 115200n8r
+
+Implementation note: Linux will look for the property "linux,stdout-path" or
+on PowerPC "stdout" if "stdout-path" is not found.  However, the
+"linux,stdout-path" and "stdout" properties are deprecated. New platforms
+should only use the "stdout-path" property.

From 75c28c09af99a0db0ccd8b4395469761aa736543 Mon Sep 17 00:00:00 2001
From: Leif Lindholm <leif.lindholm@linaro.org>
Date: Fri, 28 Nov 2014 11:34:28 +0000
Subject: [PATCH 38/42] of: add optional options parameter to
 of_find_node_by_path()

Update of_find_node_by_path():
1) Rename function to of_find_node_opts_by_path(), adding an optional
   pointer argument. Provide a static inline wrapper version of
   of_find_node_by_path() which calls the new function with NULL as
   the optional argument.
2) Ignore any part of the path beyond and including the ':' separator.
3) Set the new provided pointer argument to the beginning of the string
   following the ':' separator.
4: Add tests.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c     | 20 ++++++++++++++++----
 drivers/of/unittest.c | 30 ++++++++++++++++++++++++++++++
 include/linux/of.h    | 14 +++++++++++++-
 3 files changed, 59 insertions(+), 5 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 99bc95e83d09..bdf051d0a7e6 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -714,10 +714,15 @@ static struct device_node *__of_find_node_by_path(struct device_node *parent,
 {
 	struct device_node *child;
 	int len = strchrnul(path, '/') - path;
+	int term;
 
 	if (!len)
 		return NULL;
 
+	term = strchrnul(path, ':') - path;
+	if (term < len)
+		len = term;
+
 	__for_each_child_of_node(parent, child) {
 		const char *name = strrchr(child->full_name, '/');
 		if (WARN(!name, "malformed device_node %s\n", child->full_name))
@@ -730,11 +735,14 @@ static struct device_node *__of_find_node_by_path(struct device_node *parent,
 }
 
 /**
- *	of_find_node_by_path - Find a node matching a full OF path
+ *	of_find_node_opts_by_path - Find a node matching a full OF path
  *	@path: Either the full path to match, or if the path does not
  *	       start with '/', the name of a property of the /aliases
  *	       node (an alias).  In the case of an alias, the node
  *	       matching the alias' value will be returned.
+ *	@opts: Address of a pointer into which to store the start of
+ *	       an options string appended to the end of the path with
+ *	       a ':' separator.
  *
  *	Valid paths:
  *		/foo/bar	Full path
@@ -744,11 +752,15 @@ static struct device_node *__of_find_node_by_path(struct device_node *parent,
  *	Returns a node pointer with refcount incremented, use
  *	of_node_put() on it when done.
  */
-struct device_node *of_find_node_by_path(const char *path)
+struct device_node *of_find_node_opts_by_path(const char *path, const char **opts)
 {
 	struct device_node *np = NULL;
 	struct property *pp;
 	unsigned long flags;
+	const char *separator = strchr(path, ':');
+
+	if (opts)
+		*opts = separator ? separator + 1 : NULL;
 
 	if (strcmp(path, "/") == 0)
 		return of_node_get(of_root);
@@ -756,7 +768,7 @@ struct device_node *of_find_node_by_path(const char *path)
 	/* The path could begin with an alias */
 	if (*path != '/') {
 		char *p = strchrnul(path, '/');
-		int len = p - path;
+		int len = separator ? separator - path : p - path;
 
 		/* of_aliases must not be NULL */
 		if (!of_aliases)
@@ -785,7 +797,7 @@ struct device_node *of_find_node_by_path(const char *path)
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 	return np;
 }
-EXPORT_SYMBOL(of_find_node_by_path);
+EXPORT_SYMBOL(of_find_node_opts_by_path);
 
 /**
  *	of_find_node_by_name - Find a node by its "name" property
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 7a7ae07d592f..1807a0458648 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -47,6 +47,7 @@ static bool selftest_live_tree;
 static void __init of_selftest_find_node_by_name(void)
 {
 	struct device_node *np;
+	const char *options;
 
 	np = of_find_node_by_path("/testcase-data");
 	selftest(np && !strcmp("/testcase-data", np->full_name),
@@ -87,6 +88,35 @@ static void __init of_selftest_find_node_by_name(void)
 	np = of_find_node_by_path("testcase-alias/missing-path");
 	selftest(!np, "non-existent alias with relative path returned node %s\n", np->full_name);
 	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", &options);
+	selftest(np && !strcmp("testoption", options),
+		 "option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", NULL);
+	selftest(np, "NULL option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption",
+				       &options);
+	selftest(np && !strcmp("testaliasoption", options),
+		 "option alias path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption", NULL);
+	selftest(np, "NULL option alias path test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("testcase-alias", &options);
+	selftest(np && !options, "option clearing test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("/", &options);
+	selftest(np && !options, "option clearing root node test failed\n");
+	of_node_put(np);
 }
 
 static void __init of_selftest_dynamic(void)
diff --git a/include/linux/of.h b/include/linux/of.h
index aa01cf5852f8..8b021db3e16e 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -236,7 +236,13 @@ extern struct device_node *of_find_matching_node_and_match(
 	const struct of_device_id *matches,
 	const struct of_device_id **match);
 
-extern struct device_node *of_find_node_by_path(const char *path);
+extern struct device_node *of_find_node_opts_by_path(const char *path,
+	const char **opts);
+static inline struct device_node *of_find_node_by_path(const char *path)
+{
+	return of_find_node_opts_by_path(path, NULL);
+}
+
 extern struct device_node *of_find_node_by_phandle(phandle handle);
 extern struct device_node *of_get_parent(const struct device_node *node);
 extern struct device_node *of_get_next_parent(struct device_node *node);
@@ -383,6 +389,12 @@ static inline struct device_node *of_find_node_by_path(const char *path)
 	return NULL;
 }
 
+static inline struct device_node *of_find_node_opts_by_path(const char *path,
+	const char **opts)
+{
+	return NULL;
+}
+
 static inline struct device_node *of_get_parent(const struct device_node *node)
 {
 	return NULL;

From 7914a7c5651a51617d952e8fa745000ed8c4f001 Mon Sep 17 00:00:00 2001
From: Leif Lindholm <leif.lindholm@linaro.org>
Date: Thu, 27 Nov 2014 17:56:07 +0000
Subject: [PATCH 39/42] of: support passing console options with stdout-path

Support specifying console options (like with console=ttyXN,<options>)
by appending them to the stdout-path property after a separating ':'.

Example:
        stdout-path = "uart0:115200";

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
[grant.likely: minor rework to shorten the diffstat]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/base.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index bdf051d0a7e6..f2be7c860cf2 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -37,6 +37,7 @@ EXPORT_SYMBOL(of_root);
 struct device_node *of_chosen;
 struct device_node *of_aliases;
 struct device_node *of_stdout;
+static const char *of_stdout_options;
 
 struct kset *of_kset;
 
@@ -1852,7 +1853,7 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 		if (IS_ENABLED(CONFIG_PPC) && !name)
 			name = of_get_property(of_aliases, "stdout", NULL);
 		if (name)
-			of_stdout = of_find_node_by_path(name);
+			of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
 	}
 
 	if (!of_aliases)
@@ -1978,7 +1979,8 @@ bool of_console_check(struct device_node *dn, char *name, int index)
 {
 	if (!dn || dn != of_stdout || console_set_on_cmdline)
 		return false;
-	return !add_preferred_console(name, index, NULL);
+	return !add_preferred_console(name, index,
+				      kstrdup(of_stdout_options, GFP_KERNEL));
 }
 EXPORT_SYMBOL_GPL(of_console_check);
 

From 5267720e7515f0fadf4cdef68dccafc18d48c806 Mon Sep 17 00:00:00 2001
From: Fabio Estevam <fabio.estevam@freescale.com>
Date: Wed, 26 Nov 2014 20:13:57 -0200
Subject: [PATCH 40/42] spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y

Since commit ce79d54ae447d651173 ("spi/of: Add OF notifier handler") the
following warning is seen on a imx53 system that has CONFIG_OF_DYNAMIC=n:

[    0.048119] ------------[ cut here ]------------
[    0.048146] WARNING: CPU: 0 PID: 1 at drivers/spi/spi.c:2419 spi_init+0x60/0xa8()
[    0.048158] Modules linked in:
[    0.048183] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.18.0-rc6-next-20141126-00003-g9388e85 #2080
[    0.048193] Hardware name: Freescale i.MX53 (Device Tree Support)
[    0.048203] Backtrace:
[    0.048235] [<80011f74>] (dump_backtrace) from [<80012110>] (show_stack+0x18/0x1c)
[    0.048246]  r6:00000973 r5:00000000 r4:00000000 r3:00000000
[    0.048284] [<800120f8>] (show_stack) from [<806b3ad8>] (dump_stack+0x88/0xa4)
[    0.048312] [<806b3a50>] (dump_stack) from [<8002a55c>] (warn_slowpath_common+0x80/0xbc)
[    0.048320]  r5:8096cfcc r4:00000000
[    0.048343] [<8002a4dc>] (warn_slowpath_common) from [<8002a5bc>] (warn_slowpath_null+0x24/0x2c)
[    0.048354]  r8:8096cf6c r7:809355ec r6:ddcd7c00 r5:812029e4 r4:00000000
[    0.048389] [<8002a598>] (warn_slowpath_null) from [<8096cfcc>] (spi_init+0x60/0xa8)
[    0.048405] [<8096cf6c>] (spi_init) from [<80008a7c>] (do_one_initcall+0x88/0x1e0)
[    0.048415]  r5:8099e018 r4:8099e018
[    0.048438] [<800089f4>] (do_one_initcall) from [<80935e38>] (kernel_init_freeable+0x110/0x1e0)
[    0.048448]  r10:80980700 r9:809806e4 r8:000000cc r7:809355ec r6:809f8940 r5:00000002
[    0.048478]  r4:8098d744
[    0.048508] [<80935d28>] (kernel_init_freeable) from [<806ae574>] (kernel_init+0x10/0xf4)
[    0.048517]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:806ae564
[    0.048547]  r4:00000000
[    0.048565] [<806ae564>] (kernel_init) from [<8000ed68>] (ret_from_fork+0x14/0x2c)
[    0.048574]  r4:00000000 r3:00000000
[    0.048616] ---[ end trace 405a65d177dae4fd ]---

Only check of_reconfig_notifier_register() in the CONFIG_OF_DYNAMIC=y case,
as intended by commit ce79d54ae447d65.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/spi/spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index bf1cab0fad66..cf4ed29c7ee6 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2415,7 +2415,7 @@ static int __init spi_init(void)
 	if (status < 0)
 		goto err2;
 
-	if (IS_ENABLED(CONFIG_OF))
+	if (IS_ENABLED(CONFIG_OF_DYNAMIC))
 		WARN_ON(of_reconfig_notifier_register(&spi_of_notifier));
 
 	return 0;

From 70161ff336674ecfd20614a9c0c61cb17a6e9e83 Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@linaro.org>
Date: Fri, 28 Nov 2014 16:03:33 +0000
Subject: [PATCH 41/42] of: Drop ->next pointer from struct device_node

The ->next pointer in struct device_node is a hanger-on from when it was
used to iterate over the whole tree by a particular device_type property
value. Those days are long over, but the fdt unflattening code still
uses it to put nodes in the unflattened tree into the same order as node
in the flat tree. By reworking the unflattening code to reverse the list
after unflattening all the children of a node, the pointer can be
dropped which gives a small amount of memory savings.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Frank Rowand <frank.rowand@sonymobile.com>
Cc: Gaurav Minocha <gaurav.minocha.os@gmail.com>
---
 drivers/of/fdt.c   | 24 ++++++++++++++++++------
 include/linux/of.h |  1 -
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 7f6ee31d5650..a41f9fdb1aa0 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -226,12 +226,8 @@ static void * unflatten_dt_node(void *blob,
 		prev_pp = &np->properties;
 		if (dad != NULL) {
 			np->parent = dad;
-			/* we temporarily use the next field as `last_child'*/
-			if (dad->next == NULL)
-				dad->child = np;
-			else
-				dad->next->sibling = np;
-			dad->next = np;
+			np->sibling = dad->child;
+			dad->child = np;
 		}
 	}
 	/* process properties */
@@ -329,6 +325,22 @@ static void * unflatten_dt_node(void *blob,
 
 	if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND)
 		pr_err("unflatten: error %d processing FDT\n", *poffset);
+
+	/*
+	 * Reverse the child list. Some drivers assumes node order matches .dts
+	 * node order
+	 */
+	if (!dryrun && np->child) {
+		struct device_node *child = np->child;
+		np->child = NULL;
+		while (child) {
+			struct device_node *next = child->sibling;
+			child->sibling = np->child;
+			np->child = child;
+			child = next;
+		}
+	}
+
 	if (nodepp)
 		*nodepp = np;
 
diff --git a/include/linux/of.h b/include/linux/of.h
index 8b021db3e16e..3f0f0ffbd5e5 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -56,7 +56,6 @@ struct device_node {
 	struct	device_node *parent;
 	struct	device_node *child;
 	struct	device_node *sibling;
-	struct	device_node *next;	/* next device of same type */
 	struct	kobject kobj;
 	unsigned long _flags;
 	void	*data;

From c46ca3c8310b61d253a39ff1375ea97912794cd1 Mon Sep 17 00:00:00 2001
From: Markus Elfring <elfring@users.sourceforge.net>
Date: Tue, 2 Dec 2014 13:54:00 +0100
Subject: [PATCH 42/42] of: Delete unnecessary check before calling
 "of_node_put()"

The of_node_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
 drivers/of/unittest.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 1807a0458648..844838e11ef1 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -516,8 +516,7 @@ static void __init of_selftest_changeset(void)
 	/* Make sure node names are constructed correctly */
 	selftest((np = of_find_node_by_path("/testcase-data/changeset/n2/n21")),
 		 "'%s' not added\n", n21->full_name);
-	if (np)
-		of_node_put(np);
+	of_node_put(np);
 
 	mutex_lock(&of_mutex);
 	selftest(!of_changeset_revert(&chgset), "revert failed\n");