On Wed, May 20, 2020 at 03:55:57PM -0700, Guru Das Srinagesh wrote: > Since the PWM framework is switching struct pwm_args.period's datatype > to u64, prepare for this transition by typecasting it to u32. > > Also, since the dividend is still a 32-bit number, any divisor greater > than the numerator will cause the quotient to be zero, so return 0 in > that case to efficiently skip the division. > > Signed-off-by: Guru Das Srinagesh <[email protected]> > --- > drivers/pwm/pwm-clps711x.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/pwm/pwm-clps711x.c b/drivers/pwm/pwm-clps711x.c > index 924d39a..da771b1 100644 > --- a/drivers/pwm/pwm-clps711x.c > +++ b/drivers/pwm/pwm-clps711x.c > @@ -43,7 +43,10 @@ static void clps711x_pwm_update_val(struct clps711x_chip > *priv, u32 n, u32 v) > static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v) > { > /* Duty cycle 0..15 max */ > - return DIV_ROUND_CLOSEST(v * 0xf, pwm->args.period); > + if (pwm->args.period > (v * 0xf)) > + return 0;
This doesn't look right to me. DIV_ROUND_CLOSEST() does rounded division and the short circuit doesn't implement that. Daniel. > + > + return DIV_ROUND_CLOSEST(v * 0xf, (u32)pwm->args.period); > } > > static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device > *pwm) > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >
