of: Add of_machine_get_match() helper

Currently, there are two helpers to match the root compatible value
against an of_device_id array:
  - of_machine_device_match() returns true if a match is found,
  - of_machine_get_match_data() returns the match data if a match is
    found.
However, there is no helper that returns the actual of_device_id
structure corresponding to the match, leading to code duplication in
various drivers.

Fix this by reworking of_machine_device_match() to return the actual
match structure, and renaming it to of_machine_get_match().
Retain the old of_machine_device_match() functionality using a cheap
static inline wrapper around the new of_machine_get_match() helper.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/14e1c03d443b1a5f210609ec3a1ebbaeab8fb3d9.1772468323.git.geert+renesas@glider.be
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

2 files changed, 13 insertions, 9 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 57420806c1a2..2a01d2a66eed 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -435,13 +435,12 @@ bool of_machine_compatible_match(const char *const *compats)
 EXPORT_SYMBOL(of_machine_compatible_match);
 
 /**
- * of_machine_device_match - Test root of device tree against a of_device_id array
+ * of_machine_get_match - Test root of device tree against an of_device_id array
  * @matches:	NULL terminated array of of_device_id match structures to search in
  *
- * Returns true if the root node has any of the given compatible values in its
- * compatible property.
+ * Returns matched entry or NULL
  */
-bool of_machine_device_match(const struct of_device_id *matches)
+const struct of_device_id *of_machine_get_match(const struct of_device_id *matches)
 {
 	struct device_node *root;
 	const struct of_device_id *match = NULL;
@@ -452,9 +451,9 @@ bool of_machine_device_match(const struct of_device_id *matches)
 		of_node_put(root);
 	}
 
-	return match != NULL;
+	return match;
 }
-EXPORT_SYMBOL(of_machine_device_match);
+EXPORT_SYMBOL(of_machine_get_match);
 
 /**
  * of_machine_get_match_data - Tell if root of device tree has a matching of_match structure
diff --git a/include/linux/of.h b/include/linux/of.h
index be6ec4916adf..b4d7d33b0ceb 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -410,7 +410,7 @@ extern int of_alias_get_id(const struct device_node *np, const char *stem);
 extern int of_alias_get_highest_id(const char *stem);
 
 bool of_machine_compatible_match(const char *const *compats);
-bool of_machine_device_match(const struct of_device_id *matches);
+const struct of_device_id *of_machine_get_match(const struct of_device_id *matches);
 const void *of_machine_get_match_data(const struct of_device_id *matches);
 
 /**
@@ -866,9 +866,9 @@ static inline bool of_machine_compatible_match(const char *const *compats)
 	return false;
 }
 
-static inline bool of_machine_device_match(const struct of_device_id *matches)
+static inline const struct of_device_id *of_machine_get_match(const struct of_device_id *matches)
 {
-	return false;
+	return NULL;
 }
 
 static inline const void *
@@ -976,6 +976,11 @@ static inline int of_numa_init(void)
 }
 #endif
 
+static inline bool of_machine_device_match(const struct of_device_id *matches)
+{
+	return of_machine_get_match(matches) != NULL;
+}
+
 static inline struct device_node *of_find_matching_node(
 	struct device_node *from,
 	const struct of_device_id *matches)