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 @@ -2169,6 +2169,32 @@ int clk_get_phase(struct clk *clk) return clk_core_get_phase(clk->core); } +/** + * 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 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 /**