fdt: Add function to return next compatible subnode

We need to iterate through subnodes of a parent, looking only at compatible nodes. Add a utility function to do this for us. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>

fdt: Add function to return next compatible subnode
We need to iterate through subnodes of a parent, looking only at compatible nodes. Add a utility function to do this for us. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>
Simon Glass · Albert ARIBAUD
1 parent 96875e7d3b
Showing 2 changed files with 32 additions and 0 deletions Side-by-side Diff
include/fdtdec.h
lib/fdtdec.c
@@ -117,6 +117,23 @@
 		enum fdt_compat_id id);
  
 /**
+ * Find the next compatible subnode for a peripheral.
+ *
+ * Do the first call with node set to the parent and depth = 0. This
+ * function will return the offset of the next compatible node. Next time
+ * you call this function, pass the node value returned last time, with
+ * depth unchanged, and the next node will be provided.
+ *
+ * @param blob		FDT blob to use
+ * @param node		Start node for search
+ * @param id		Compatible ID to look for (enum fdt_compat_id)
+ * @param depthp	Current depth (set to 0 before first call)
+ * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
+ */
+int fdtdec_next_compatible_subnode(const void *blob, int node,
+		enum fdt_compat_id id, int *depthp);
+
+/**
  * Look up an address property in a node and return it as an address.
  * The property must hold either one address with no trailing data or
  * one address with a length. This is only tested on 32-bit machines.
@@ -133,6 +133,21 @@
 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
 }
  
+int fdtdec_next_compatible_subnode(const void *blob, int node,
+		enum fdt_compat_id id, int *depthp)
+{
+	do {
+		node = fdt_next_node(blob, node, depthp);
+	} while (*depthp > 1);
+
+	/* If this is a direct subnode, and compatible, return it */
+	if (*depthp == 1 && 0 == fdt_node_check_compatible(
+						blob, node, compat_names[id]))
+		return node;
+
+	return -FDT_ERR_NOTFOUND;
+}
+
 int fdtdec_next_alias(const void *blob, const char *name,
 		enum fdt_compat_id id, int *upto)
 {
...	...	@@ -117,6 +117,23 @@
117	117	enum fdt_compat_id id);
118	118
119	119	/**
	120	+ * Find the next compatible subnode for a peripheral.
	121	+ *
	122	+ * Do the first call with node set to the parent and depth = 0. This
	123	+ * function will return the offset of the next compatible node. Next time
	124	+ * you call this function, pass the node value returned last time, with
	125	+ * depth unchanged, and the next node will be provided.
	126	+ *
	127	+ * @param blob FDT blob to use
	128	+ * @param node Start node for search
	129	+ * @param id Compatible ID to look for (enum fdt_compat_id)
	130	+ * @param depthp Current depth (set to 0 before first call)
	131	+ * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
	132	+ */
	133	+int fdtdec_next_compatible_subnode(const void *blob, int node,
	134	+ enum fdt_compat_id id, int *depthp);
	135	+
	136	+/**
120	137	* Look up an address property in a node and return it as an address.
121	138	* The property must hold either one address with no trailing data or
122	139	* one address with a length. This is only tested on 32-bit machines.
...	...	@@ -133,6 +133,21 @@
133	133	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
134	134	}
135	135
	136	+int fdtdec_next_compatible_subnode(const void *blob, int node,
	137	+ enum fdt_compat_id id, int *depthp)
	138	+{
	139	+ do {
	140	+ node = fdt_next_node(blob, node, depthp);
	141	+ } while (*depthp > 1);
	142	+
	143	+ /* If this is a direct subnode, and compatible, return it */
	144	+ if (*depthp == 1 && 0 == fdt_node_check_compatible(
	145	+ blob, node, compat_names[id]))
	146	+ return node;
	147	+
	148	+ return -FDT_ERR_NOTFOUND;
	149	+}
	150	+
136	151	int fdtdec_next_alias(const void blob, const char name,
137	152	enum fdt_compat_id id, int *upto)
138	153	{