In the !CONFIG_OF case, replace the of_match_node() macro implementation
by a static function. This ensures drivers calling of_match_node() can
be COMPILE_TESTed.
include/linux/of.h declares of_match_node() like this:
#ifdef CONFIG_OF
extern const struct of_device_id *of_match_node(
const struct of_device_id *matches, const struct device_node *node);
#else
#define of_match_node(_matches, _node) NULL
#endif
When used inside an expression, those two implementations behave truly
differently. The macro implementation has (at least) two pitfalls:
- Arguments are removed by the preprocessor meaning they do not appear
to the compiler. This can give "defined but not used" warnings.
- The returned value type is (void *)
versus (const struct of_device_id *).
It works okay if the value is stored in a variable, thanks to C's
implicit void pointer casting rules. It causes build errors if used
like `of_match_data(...)->data`.
Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
---
include/linux/of.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/linux/of.h b/include/linux/of.h
index a0bedd038a05..f973ae119504 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -891,7 +891,13 @@ static inline const void *of_device_get_match_data(const struct device *dev)
}
#define of_match_ptr(_ptr) NULL
-#define of_match_node(_matches, _node) NULL
+
+static inline const struct of_device_id *of_match_node(
+ const struct of_device_id *matches, const struct device_node *node)
+{
+ return NULL;
+}
+
#endif /* CONFIG_OF */
/* Default string compare functions, Allow arch asm/prom.h to override */
---
base-commit: 256abd8e550ce977b728be79a74e1729438b4948
change-id: 20240708-of-match-node-ad30140a0a9c
Best regards,
--
Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
