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Date:   Tue, 12 May 2020 17:39:38 -0700
From:   Guru Das Srinagesh <>
        Thierry Reding <>,
        Uwe Kleine-K├Ânig 
Cc:     Subbaraman Narayanamurthy <>,
        David Collins <>,, Joe Perches <>,
        Stephen Boyd <>,
        Lee Jones <>,
        Arnd Bergmann <>,
        Geert Uytterhoeven <>,
        Guenter Roeck <>,
        Daniel Thompson <>,
        Dan Carpenter <>,,
        Guru Das Srinagesh <>
Subject: [RESEND PATCH v14 04/11] pwm: clps711x: Cast period to u32 before use as divisor

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 <>
 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;
+	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

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