2 files changed, 44 insertions, 0 deletions

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b9f85fc2ce3f..237f23f68bfc 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2170,6 +2170,32 @@ int clk_get_phase(struct clk *clk)
 }
 
 /**
+ * clk_is_match - check if two clk's point to the same hardware clock
+ * @p: clk compared against q
+ * @q: clk compared against p
+ *
+ * Returns true if the two struct clk pointers both point to the same hardware
+ * clock node. Put differently, returns true if struct clk *p and struct clk *q
+ * share the same struct clk_core object.
+ *
+ * Returns false otherwise. Note that two NULL clks are treated as matching.
+ */
+bool clk_is_match(const struct clk *p, const struct clk *q)
+{
+        /* trivial case: identical struct clk's or both NULL */
+        if (p == q)
+                return true;
+
+        /* true if clk->core pointers match. Avoid derefing garbage */
+        if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
+                if (p->core == q->core)
+                        return true;
+
+        return false;
+}
+EXPORT_SYMBOL_GPL(clk_is_match);
+
+/**
  * __clk_init - initialize the data structures in a struct clk
  * @dev:        device initializing this clk, placeholder for now
  * @clk:        clk being initialized
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 8381bbfbc308..68c16a6bedb3 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -125,6 +125,19 @@ int clk_set_phase(struct clk *clk, int degrees);
  */
 int clk_get_phase(struct clk *clk);
 
+/**
+ * clk_is_match - check if two clk's point to the same hardware clock
+ * @p: clk compared against q
+ * @q: clk compared against p
+ *
+ * Returns true if the two struct clk pointers both point to the same hardware
+ * clock node. Put differently, returns true if struct clk *p and struct clk *q
+ * share the same struct clk_core object.
+ *
+ * Returns false otherwise. Note that two NULL clks are treated as matching.
+ */
+bool clk_is_match(const struct clk *p, const struct clk *q);
+
 #else
 
 static inline long clk_get_accuracy(struct clk *clk)
@@ -142,6 +155,11 @@ static inline long clk_get_phase(struct clk *clk)
         return -ENOTSUPP;
 }
 
+static inline bool clk_is_match(const struct clk *p, const struct clk *q)
+{
+        return p == q;
+}
+
 #endif
 
 /**