[PATCH 1/2] clk: Check that composite clock's div has set_rate()

[Igor Prusov]

It's possible for composite clocks to have a divider that does not
implement set_rate() operation. For example, sandbox_clk_composite()
registers composite clock with a divider that only has get_rate().
Currently clk_composite_set_rate() only checks thate rate_ops are
present, so for sandbox it will cause NULL dereference during
clk_set_rate().

This patch adds rate_ops->set_rate check tp clk_composite_set_rate().

Signed-off-by: Igor Prusov <ivprusov at salutedevices.com>
---

 drivers/clk/clk-composite.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c
index 6eb2b8133a..d2e5a1ae40 100644
--- a/drivers/clk/clk-composite.c
+++ b/drivers/clk/clk-composite.c
@@ -66,7 +66,7 @@ static ulong clk_composite_set_rate(struct clk *clk, unsigned long rate)
 	const struct clk_ops *rate_ops = composite->rate_ops;
 	struct clk *clk_rate = composite->rate;
 
-	if (rate && rate_ops)
+	if (rate && rate_ops && rate_ops->set_rate)
 		return rate_ops->set_rate(clk_rate, rate);
 	else
 		return clk_get_rate(clk);
-- 
2.34.1