clk: composite: improve rate_hw sanity check logic

The function pointer population and sanity checking logic got a bit ugly
with the advent of the .determine_rate callback. Clean it up.

Signed-off-by: Mike Turquette <mturquette@linaro.org>

diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c
index faf7c32..b9355da 100644 (file)
--- a/drivers/clk/clk-composite.c
+++ b/drivers/clk/clk-composite.c
@@ -226,21 +226,27 @@ struct clk *clk_register_composite(struct device *dev, const char *name,
                        clk = ERR_PTR(-EINVAL);
                        goto err;
                }
+               clk_composite_ops->recalc_rate = clk_composite_recalc_rate;
 
-               /* .round_rate is a prerequisite for .set_rate */
-               if (rate_ops->round_rate) {
-                       clk_composite_ops->round_rate = clk_composite_round_rate;
-                       if (rate_ops->set_rate) {
-                               clk_composite_ops->set_rate = clk_composite_set_rate;
-                       }
+               if (rate_ops->determine_rate)
+                       clk_composite_ops->determine_rate =
+                               clk_composite_determine_rate;
+               else if (rate_ops->round_rate)
+                       clk_composite_ops->round_rate =
+                               clk_composite_round_rate;
+
+               /* .set_rate requires either .round_rate or .determine_rate */
+               if (rate_ops->set_rate) {
+                       if (rate_ops->determine_rate || rate_ops->round_rate)
+                               clk_composite_ops->set_rate =
+                                               clk_composite_set_rate;
+                       else
+                               WARN(1, "%s: missing round_rate op is required\n",
+                                               __func__);
                }
 
                composite->rate_hw = rate_hw;
                composite->rate_ops = rate_ops;
-               clk_composite_ops->recalc_rate = clk_composite_recalc_rate;
-               if (rate_ops->determine_rate ||
-                   (rate_ops->round_rate && clk_composite_ops->set_parent))
-                       clk_composite_ops->determine_rate = clk_composite_determine_rate;
        }
 
        if (gate_hw && gate_ops) {