diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 541d32c00cbc..91ec3232d630 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -46,7 +46,7 @@ static struct opp_device *_find_opp_dev(const struct device *dev,
 	return NULL;
 }
 
-struct opp_table *_find_opp_table_unlocked(struct device *dev)
+static struct opp_table *_find_opp_table_unlocked(struct device *dev)
 {
 	struct opp_table *opp_table;