clk: sunxi-ng: Call divider_round_rate if we only have a single parent

The divider_get_val function that is used in our determine_rate callback
doesn't try to change the parent rate at all, while clk_divider_bestdiv,
used in divider_round_rate, does.

If we have a single parent, call divider_round_rate.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>

drivers/clk/sunxi-ng/ccu_div.c

@@ -77,6 +77,18 @@ static int ccu_div_determine_rate(struct clk_hw *hw,
 {
 	struct ccu_div *cd = hw_to_ccu_div(hw);
 
+	if (clk_hw_get_num_parents(hw) == 1) {
+		req->rate = divider_round_rate(hw, req->rate,
+					       &req->best_parent_rate,
+					       cd->div.table,
+					       cd->div.width,
+					       cd->div.flags);
+
+		req->best_parent_hw = clk_hw_get_parent(hw);
+
+		return 0;
+	}
+
 	return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
 					     req, ccu_div_round_rate, cd);
 }