[RESEND PATCH v4 2/3] software node: Let args be NULL in software_node_get_reference_args

[Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>]

fwnode_get_property_reference_args() may not be called with args argument
NULL and while OF already supports this. Add the missing NULL check.

The purpose is to be able to count the references.

Fixes: b06184acf751 ("software node: Add software_node_get_reference_args()")
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
 drivers/base/swnode.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 1886995a0b3a..079bd14bdedc 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -541,6 +541,9 @@ software_node_get_reference_args(const struct fwnode_handle *fwnode,
 	if (nargs > NR_FWNODE_REFERENCE_ARGS)
 		return -EINVAL;
 
+	if (!args)
+		return 0;
+
 	args->fwnode = software_node_get(refnode);
 	args->nargs = nargs;
 
-- 
2.39.2