clk: at91: replace prog clk round_rate with determine_rate

Implement the determine_rate callback to choose the best parent clk that
fulfills the requested rate.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c
index fd792b203eaf2fcf1ca8037a86b34247ba94e36f..eff701665f049aa5ddca08c13738bee59a62c850 100644 (file)
--- a/drivers/clk/at91/clk-programmable.c
+++ b/drivers/clk/at91/clk-programmable.c
@@ -102,40 +102,40 @@ static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
        return parent_rate >> prog->pres;
 }
 
-static long clk_programmable_round_rate(struct clk_hw *hw, unsigned long rate,
-                                       unsigned long *parent_rate)
+static long clk_programmable_determine_rate(struct clk_hw *hw,
+                                           unsigned long rate,
+                                           unsigned long *best_parent_rate,
+                                           struct clk **best_parent_clk)
 {
-       unsigned long best_rate = *parent_rate;
-       unsigned long best_diff;
-       unsigned long new_diff;
-       unsigned long cur_rate;
-       int shift = shift;
-
-       if (rate > *parent_rate)
-               return *parent_rate;
-       else
-               best_diff = *parent_rate - rate;
-
-       if (!best_diff)
-               return best_rate;
+       struct clk *parent = NULL;
+       long best_rate = -EINVAL;
+       unsigned long parent_rate;
+       unsigned long tmp_rate;
+       int shift;
+       int i;
 
-       for (shift = 1; shift < PROG_PRES_MASK; shift++) {
-               cur_rate = *parent_rate >> shift;
+       for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+               parent = clk_get_parent_by_index(hw->clk, i);
+               if (!parent)
+                       continue;
 
-               if (cur_rate > rate)
-                       new_diff = cur_rate - rate;
-               else
-                       new_diff = rate - cur_rate;
+               parent_rate = __clk_get_rate(parent);
+               for (shift = 0; shift < PROG_PRES_MASK; shift++) {
+                       tmp_rate = parent_rate >> shift;
+                       if (tmp_rate <= rate)
+                               break;
+               }
 
-               if (!new_diff)
-                       return cur_rate;
+               if (tmp_rate > rate)
+                       continue;
 
-               if (new_diff < best_diff) {
-                       best_diff = new_diff;
-                       best_rate = cur_rate;
+               if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) {
+                       best_rate = tmp_rate;
+                       *best_parent_rate = parent_rate;
+                       *best_parent_clk = parent;
                }
 
-               if (rate > cur_rate)
+               if (!best_rate)
                        break;
        }
 
@@ -228,7 +228,7 @@ static const struct clk_ops programmable_ops = {
        .prepare = clk_programmable_prepare,
        .is_prepared = clk_programmable_is_ready,
        .recalc_rate = clk_programmable_recalc_rate,
-       .round_rate = clk_programmable_round_rate,
+       .determine_rate = clk_programmable_determine_rate,
        .get_parent = clk_programmable_get_parent,
        .set_parent = clk_programmable_set_parent,
        .set_rate = clk_programmable_set_rate,