Re: [U-Boot] [PATCH] bugfix i.mx6 pwm: prevent overflow of period_c * duty_ns by casting duty_ns to ull first. This bug came up when trying to create a 200 Hz PWM.

Hello Brecht Neyrinck,

Am 27.04.2015 14:11, schrieb Brecht Neyrinck:

---

drivers/pwm/pwm-imx-util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) mode change 100644 => 100755 drivers/pwm/pwm-imx-util.c

diff --git a/drivers/pwm/pwm-imx-util.c b/drivers/pwm/pwm-imx-util.c index f1d0b35..777a8bf 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;

Thanks for this ... Hmm... this code is directly from linux drivers/pwm/pwm-imx.c ... Do you have running a linux on your hw? Could you verify this in linux too?

Thanks!

Acked-by: Heiko Schocher hs@denx.de

bye, Heiko

do_div(c, period_ns); *duty_c = c;