fdt: Add a function to count strings
Given a device tree node and a property name, the fdt_count_strings()
function counts the number of strings found in the property value.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/include/libfdt.h b/include/libfdt.h
index a1ef1e1..cf97bf0 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -857,6 +857,15 @@
*/
int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
+/**
+ * fdt_count_strings - count the number of strings in a string list
+ * @fdt: pointer to the device tree blob
+ * @node: offset of the node
+ * @property: name of the property containing the string list
+ * @return: the number of strings in the given property
+ */
+int fdt_count_strings(const void *fdt, int node, const char *property);
+
/**********************************************************************/
/* Read-only functions (addressing related) */
/**********************************************************************/
diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c
index 36af043..cb06a9b 100644
--- a/lib/libfdt/fdt_ro.c
+++ b/lib/libfdt/fdt_ro.c
@@ -491,6 +491,26 @@
return 0;
}
+int fdt_count_strings(const void *fdt, int node, const char *property)
+{
+ int length, i, count = 0;
+ const char *list;
+
+ list = fdt_getprop(fdt, node, property, &length);
+ if (!list)
+ return -length;
+
+ for (i = 0; i < length; i++) {
+ int len = strlen(list);
+
+ list += len + 1;
+ i += len;
+ count++;
+ }
+
+ return count;
+}
+
int fdt_node_check_compatible(const void *fdt, int nodeoffset,
const char *compatible)
{