[PATCH 03/14] pwm: rockchip: Fix period and duty_cycle approximation
From: Boris Brezillon <hidden>
Date: 2016-06-03 08:29:10
Also in:
linux-arm-kernel, linux-pwm, linux-rockchip, lkml
Subsystem:
arm/rockchip soc support, pwm subsystem, the rest · Maintainers:
Heiko Stuebner, Uwe Kleine-König, Linus Torvalds
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