On Thu, Jan 26, 2017 at 5:55 PM, Maxime Ripard
[off-list ref] wrote:

Hi Chen-Yu,

On Tue, Jan 24, 2017 at 10:32:20AM +0800, Chen-Yu Tsai wrote:

quoted

The determine_rate helper used ccu_mux_helper_adjust_parent_for_prediv()
to adjust the parent_rate to account for pre-dividers, but then passed
the pristine parent clock rate from clk_hw_get_rate() to the round()
callback, thereby ignoring the pre-divider adjustment. In addition,
it was saving the adjusted parent rate back into struct
clk_rate_request.

This patch fixes this by saving the pristine parent clock rate, and
adding a copy that is adjusted and passed to the round() callback.
The pristine copy, if it is the best solution, would be saved back
to struct clk_rate_request.

Signed-off-by: Chen-Yu Tsai <redacted>
---
 drivers/clk/sunxi-ng/ccu_mux.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/sunxi-ng/ccu_mux.c b/drivers/clk/sunxi-ng/ccu_mux.c
index 858a48621631..3445041894e7 100644
--- a/drivers/clk/sunxi-ng/ccu_mux.c
+++ b/drivers/clk/sunxi-ng/ccu_mux.c

@@ -71,7 +71,7 @@ int ccu_mux_helper_determine_rate(struct ccu_common *common,
      unsigned int i;

      for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
-             unsigned long tmp_rate, parent_rate;
+             unsigned long tmp_rate, parent_rate, adj_parent_rate;
              struct clk_hw *parent;

              parent = clk_hw_get_parent_by_index(hw, i);

@@ -79,10 +79,11 @@ int ccu_mux_helper_determine_rate(struct ccu_common *common,
                      continue;

              parent_rate = clk_hw_get_rate(parent);
+             adj_parent_rate = parent_rate;
              ccu_mux_helper_adjust_parent_for_prediv(common, cm, i,
-                                                     &parent_rate);
+                                                     &adj_parent_rate);

-             tmp_rate = round(cm, clk_hw_get_rate(parent), req->rate, data);
+             tmp_rate = round(cm, parent_rate, req->rate, data);

Shouldn't you use the adjusted rate here too?

You're right. Thanks!

ChenYu