[U-Boot] [PATCH 01/13] fdt: Add a function to look up a /chosen property

Simon Glass
2015-08-29T15:10:10Z

It is sometimes useful to find a property in the chosen node. Add a function
for this.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

include/fdtdec.h | 11 ++++++++++-
lib/fdtdec.c | 15 ++++++++++-----
2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/include/fdtdec.h b/include/fdtdec.h
index 0cb6fa0..2049d12 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -534,7 +534,16 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
int *seqp);

/**
- * Get the offset of the given chosen node
+ * Get a property from the /chosen node
+ *
+ * @param blob Device tree blob (if NULL, then NULL is returned)
+ * @param name Property name to look up
+ * @return Value of property, or NULL if it does not exist
+ */
+const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
+
+/**
+ * Get the offset of the given /chosen node
*
* This looks up a property in /chosen containing the path to another node,
* then finds the offset of that node.
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 81b54f8..38888de 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -529,16 +529,21 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
return -ENOENT;
}

-int fdtdec_get_chosen_node(const void *blob, const char *name)
+const char *fdtdec_get_chosen_prop(const void *blob, const char *name)
{
- const char *prop;
int chosen_node;
- int len;

if (!blob)
- return -FDT_ERR_NOTFOUND;
+ return NULL;
chosen_node = fdt_path_offset(blob, "/chosen");
- prop = fdt_getprop(blob, chosen_node, name, &len);
+ return fdt_getprop(blob, chosen_node, name, NULL);
+}
+
+int fdtdec_get_chosen_node(const void *blob, const char *name)
+{
+ const char *prop;
+
+ prop = fdtdec_get_chosen_prop(blob, name);
if (!prop)
return -FDT_ERR_NOTFOUND;
return fdt_path_offset(blob, prop);
--
2.5.0.457.gab17608