This ports Linux commit:
| commit c5d264d4b527c96ae8903376a4b195df47b05203
| Author: Michael Walle <mich...@walle.cc>
| Date: Mon Feb 6 13:43:43 2023 +0000
|
| of: base: add of_parse_phandle_with_optional_args()
|
| Add a new variant of the of_parse_phandle_with_args() which treats the
| cells name as optional. If it's missing, it is assumed that the phandle
| has no arguments.
|
| Up until now, a nvmem node didn't have any arguments, so all the device
| trees haven't any '#*-cells' property. But there is a need for an
| additional argument for the phandle, for which we need a '#*-cells'
| property. Therefore, we need to support nvmem nodes with and without
| this property.
|
| Signed-off-by: Michael Walle <mich...@walle.cc>
| Reviewed-by: Rob Herring <r...@kernel.org>
| Signed-off-by: Srinivas Kandagatla <srinivas.kandaga...@linaro.org>
| Link:
https://lore.kernel.org/r/20230206134356.839737-10-srinivas.kandaga...@linaro.org
| Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Signed-off-by: Marco Felsch <m.fel...@pengutronix.de>
---
include/of.h | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/include/of.h b/include/of.h
index
841ab0408b19f6341e67685891bc4da4e82771c8..55ae5f369793e97abd78cd959a76d18ad17d5e3a
100644
--- a/include/of.h
+++ b/include/of.h
@@ -366,6 +366,31 @@ static inline int of_parse_phandle_with_args(const struct
device_node *np,
cell_count, index, out_args);
}
+/**
+ * of_parse_phandle_with_optional_args() - Find a node pointed by phandle in a
list
+ * @np: pointer to a device tree node containing a list
+ * @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_args: optional pointer to output arguments structure (will be filled)
+ *
+ * Same as of_parse_phandle_with_args() except that if the cells_name property
+ * is not found, cell_count of 0 is assumed.
+ *
+ * This is used to useful, if you have a phandle which didn't have arguments
+ * before and thus doesn't have a '#*-cells' property but is now migrated to
+ * having arguments while retaining backwards compatibility.
+ */
+static inline int of_parse_phandle_with_optional_args(const struct device_node
*np,
+ const char *list_name,
+ const char *cells_name,
+ int index,
+ struct of_phandle_args
*out_args)
+{
+ return __of_parse_phandle_with_args(np, list_name, cells_name,
+ 0, index, out_args);
+}
+
extern int of_count_phandle_with_args(const struct device_node *np,
const char *list_name, const char *cells_name);
--
2.39.5
