of: of_parse_phandles_with_args() learns to differentiate 'hole' cells
Given this list (contains three gpio specifiers, one of which is a hole):
gpios = <&phandle1 1 2 3
0 /* a hole */
&phandle2 4 5 6>;
of_parse_phandles_with_args() would report -ENOENT for the `hole'
specifier item, the same error value is used to report the end of the
list, for example.
Sometimes we want to differentiate holes from real errors -- for
example when we want to count all the [syntax correct] specifiers.
With this patch of_parse_phandles_with_args() will report -EEXITS when
somebody requested to parse a hole.
Also, make the out_{node,args} arguments optional, when counting we
don't really need the out values.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/drivers/of/base.c b/drivers/of/base.c
index cf04d4d..cd17092 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -499,8 +499,8 @@
* @list_name: property name that contains a list
* @cells_name: property name that specifies phandles' arguments count
* @index: index of a phandle to parse out
- * @out_node: pointer to device_node struct pointer (will be filled)
- * @out_args: pointer to arguments pointer (will be filled)
+ * @out_node: optional pointer to device_node struct pointer (will be filled)
+ * @out_args: optional pointer to arguments pointer (will be filled)
*
* This function is useful to parse lists of phandles and their arguments.
* Returns 0 on success and fills out_node and out_args, on error returns
@@ -534,7 +534,7 @@
int size;
int cur_index = 0;
struct device_node *node = NULL;
- const void *args;
+ const void *args = NULL;
list = of_get_property(np, list_name, &size);
if (!list) {
@@ -580,16 +580,26 @@
of_node_put(node);
node = NULL;
+ args = NULL;
cur_index++;
}
if (!node) {
- ret = -ENOENT;
+ /*
+ * args w/o node indicates that the loop above has stopped at
+ * the 'hole' cell. Report this differently.
+ */
+ if (args)
+ ret = -EEXIST;
+ else
+ ret = -ENOENT;
goto err0;
}
- *out_node = node;
- *out_args = args;
+ if (out_node)
+ *out_node = node;
+ if (out_args)
+ *out_args = args;
return 0;
err1: