[PATCH v3] of: property: Increase NR_FWNODE_REFERENCE_ARGS

[Zijun Hu]

From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>

Currently, the following two macros have different values:

// The maximal argument count for firmware node reference
 #define NR_FWNODE_REFERENCE_ARGS	8
// The maximal argument count for DT node reference
 #define MAX_PHANDLE_ARGS 16

It may cause firmware node reference's argument count out of range if
directly assign DT node reference's argument count to firmware's.

drivers/of/property.c:of_fwnode_get_reference_args() is doing the direct
assignment, so may cause firmware's argument count @args->nargs got out
of range, namely, in [9, 16].

Fix by increasing NR_FWNODE_REFERENCE_ARGS to 16 to meet DT requirement.

Fixes: 3e3119d3088f ("device property: Introduce fwnode_property_get_reference_args")
Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
---
May remove MAX_PHANDLE_ARGS and use NR_FWNODE_REFERENCE_ARGS instead later.
---
Changes in v3:
- Remove RFC, correct title and commit message.
- Link to v2: https://lore.kernel.org/r/20250114-fix_arg_count-v2-1-efa35ee6572b@xxxxxxxxxxx

Changes in v2:
- Increase macro @NR_FWNODE_REFERENCE_ARGS to align with @MAX_PHANDLE_ARGS.
- Correct fix tag and send as RFC patch.
- Link to v1: https://lore.kernel.org/r/20250109-of_core_fix-v4-7-db8a72415b8c@xxxxxxxxxxx
---
 include/linux/fwnode.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 0731994b9d7c832cae8a30063f3a64194e4f19aa..6fa0a268d53827a376d7f258c6194a2a088e4325 100644
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -91,7 +91,7 @@ struct fwnode_endpoint {
 #define SWNODE_GRAPH_PORT_NAME_FMT		"port@%u"
 #define SWNODE_GRAPH_ENDPOINT_NAME_FMT		"endpoint@%u"
 
-#define NR_FWNODE_REFERENCE_ARGS	8
+#define NR_FWNODE_REFERENCE_ARGS	16
 
 /**
  * struct fwnode_reference_args - Fwnode reference with additional arguments

---
base-commit: 40fc0083a9dbcf2e81b1506274cb541f84d022ed
change-id: 20250114-fix_arg_count-73feae90fccb

Best regards,
-- 
Zijun Hu <quic_zijuhu@xxxxxxxxxxx>