[PATCH RFC v9 01/20] clk: divider: Correct parent clk round rate if no bestdiv is normally found

[Liu Ying]

If no best divider is normally found, we will try to use the maximum divider.
We should not set the parent clock rate to be 1Hz by force for being rounded.
Instead, we should take the maximum divider as a base and calculate a correct
parent clock rate for being rounded.

Signed-off-by: Liu Ying <Ying.Liu at freescale.com>
---
v8->v9:
 * Rebase onto the imx-drm/next branch of Philipp Zabel's open git repository.

v7->v8:
 * None.

v6->v7:
 * None.

v5->v6:
 * None.

v4->v5:
 * None.

v3->v4:
 * None.

v2->v3:
 * None.

v1->v2:
 * None.

 drivers/clk/clk-divider.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index c0a842b..f641d4b 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -311,7 +311,8 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
 
 	if (!bestdiv) {
 		bestdiv = _get_maxdiv(divider);
-		*best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1);
+		*best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
+						MULT_ROUND_UP(rate, bestdiv));
 	}
 
 	return bestdiv;
-- 
2.1.0