[PATCH 2/2] pwm: iqs620a: Use 64-bit division

From: Thierry Reding
Date: Mon Jun 15 2020 - 10:16:24 EST


The PWM framework is going to change the PWM period and duty cycles to
be 64-bit unsigned integers. To avoid build errors on platforms that do
not natively support 64-bit division, use explicity 64-bit division.

Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
---
drivers/pwm/pwm-iqs620a.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/pwm/pwm-iqs620a.c b/drivers/pwm/pwm-iqs620a.c
index 674f0e238ba0..b2bb27eff623 100644
--- a/drivers/pwm/pwm-iqs620a.c
+++ b/drivers/pwm/pwm-iqs620a.c
@@ -46,7 +46,8 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
{
struct iqs620_pwm_private *iqs620_pwm;
struct iqs62x_core *iqs62x;
- int duty_scale, ret;
+ u64 duty_scale;
+ int ret;

if (state->polarity != PWM_POLARITY_NORMAL)
return -ENOTSUPP;
@@ -69,7 +70,7 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
* For lower duty cycles (e.g. 0), the PWM output is simply disabled to
* allow an external pull-down resistor to hold the GPIO3/LTX pin low.
*/
- duty_scale = state->duty_cycle * 256 / IQS620_PWM_PERIOD_NS;
+ duty_scale = div_u64(state->duty_cycle * 256, IQS620_PWM_PERIOD_NS);

mutex_lock(&iqs620_pwm->lock);

@@ -81,7 +82,7 @@ static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
}

if (duty_scale) {
- u8 duty_val = min(duty_scale - 1, 0xFF);
+ u8 duty_val = min_t(u64, duty_scale - 1, 0xff);

ret = regmap_write(iqs62x->regmap, IQS620_PWM_DUTY_CYCLE,
duty_val);
--
2.24.1