[PATCH 03/14] pwm: rockchip: Fix period and duty_cycle approximation

Boris Brezillon
2016-06-03T08:23:01Z

The current implementation always round down the duty and period
values, while it would be better to round them to the closest integer.

Signed-off-by: Boris Brezillon <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
---
drivers/pwm/pwm-rockchip.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c
index 7d9cc90..68d72ce 100644
--- a/drivers/pwm/pwm-rockchip.c
+++ b/drivers/pwm/pwm-rockchip.c
@@ -114,12 +114,11 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
* default prescaler value for all practical clock rate values.
*/
div = clk_rate * period_ns;
- do_div(div, pc->data->prescaler * NSEC_PER_SEC);
- period = div;
+ period = DIV_ROUND_CLOSEST_ULL(div,
+ pc->data->prescaler * NSEC_PER_SEC);

div = clk_rate * duty_ns;
- do_div(div, pc->data->prescaler * NSEC_PER_SEC);
- duty = div;
+ duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);

ret = clk_enable(pc->clk);
if (ret)
--
2.7.4