[U-Boot] [PATCH 02/23] fdt: Add a function to get the index of a string

Thierry Reding
2014-08-18T07:16:15Z

From: Thierry Reding <treding@nvidia.com>

Given a device tree node and a property name, the fdt_get_string_index()
function will look up a given string in the string list contained in the
property's value and return its index.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
include/libfdt.h | 11 +++++++++++
lib/libfdt/fdt_ro.c | 28 ++++++++++++++++++++++++++++
2 files changed, 39 insertions(+)

diff --git a/include/libfdt.h b/include/libfdt.h
index e7f991b388cf..4d7fb2681669 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -857,6 +857,17 @@ int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
*/
int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);

+/**
+ * fdt_get_string_index - get the index of a string 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
+ * @string: string to look up in the string list
+ * @return the index of the string or negative on error
+ */
+int fdt_get_string_index(const void *fdt, int node, const char *property,
+ const char *string);
+
/**********************************************************************/
/* Read-only functions (addressing related) */
/**********************************************************************/
diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c
index 17cd11333c1e..f211c64ca7ca 100644
--- a/lib/libfdt/fdt_ro.c
+++ b/lib/libfdt/fdt_ro.c
@@ -14,6 +14,8 @@

#include "libfdt_internal.h"

+#define max(x, y) (((x) < (y)) ? (y) : (x))
+
static int _fdt_nodename_eq(const void *fdt, int offset,
const char *s, int len)
{
@@ -491,6 +493,32 @@ int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
return 0;
}

+int fdt_get_string_index(const void *fdt, int node, const char *property,
+ const char *string)
+{
+ const char *list, *end;
+ int len, index = 0;
+
+ list = fdt_getprop(fdt, node, property, &len);
+ if (!list)
+ return len;
+
+ end = list + len;
+
+ while (list < end) {
+ int n = strlen(string);
+ int m = strlen(list);
+
+ if (n == m && memcmp(list, string, n) == 0)
+ return index;
+
+ list += max(n, m) + 1;
+ index++;
+ }
+
+ return -FDT_ERR_NOTFOUND;
+}
+
int fdt_node_check_compatible(const void *fdt, int nodeoffset,
const char *compatible)
{
--
2.0.4