From b2580877b599f94730d8d174e0d83cb89217e2d6 Mon Sep 17 00:00:00 2001 From: Brecht Neyrinck Date: Wed, 6 May 2015 09:57:48 +0200 Subject: [PATCH] bugfix i.mx6 pwm: prevent overflow of period_c * duty_ns Prevent overflow by casting duty_ns to ull first. This bug came up when trying to create a 200 Hz PWM Signed-off-by: Brecht Neyrinck Acked-by: Heiko Schocher --- drivers/pwm/pwm-imx-util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-imx-util.c b/drivers/pwm/pwm-imx-util.c index f1d0b35..79d86028 100644 --- a/drivers/pwm/pwm-imx-util.c +++ b/drivers/pwm/pwm-imx-util.c @@ -56,7 +56,7 @@ int pwm_imx_get_parms(int period_ns, int duty_ns, unsigned long *period_c, *prescale = *period_c / 0x10000 + 1; *period_c /= *prescale; - c = (unsigned long long)(*period_c * duty_ns); + c = *period_c * (unsigned long long)duty_ns; do_div(c, period_ns); *duty_c = c;