clk: fix possible null pointer dereference

The commit 646cafc6 (clk: Change clk_ops->determine_rate to
return a clk_hw as the best parent) opens a possibility for
null pointer dereference, fix this.

Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index f4963b7d4e17d41b6a6553854c5250a7e90bfdef..d48ac71c6c8b173793a31e95ebaa93749e883a76 100644 (file)
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1366,7 +1366,7 @@ static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate)
                new_rate = clk->ops->determine_rate(clk->hw, rate,
                                                    &best_parent_rate,
                                                    &parent_hw);
-               parent = parent_hw->clk;
+               parent = parent_hw ? parent_hw->clk : NULL;
        } else if (clk->ops->round_rate) {
                new_rate = clk->ops->round_rate(clk->hw, rate,
                                                &best_parent_rate);