yes, this is wrong. Also, the logic would be broken as the two apis do_div() and div64_u64 return values are completely different. Thanks, Jyoti On Mon, Feb 14, 2022 at 3:01 AM Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: > > On Sun, 13 Feb 2022 19:54:01 +0100 > Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> wrote: > > > Le 13/02/2022 à 19:50, Christophe JAILLET a écrit : > > > Le 13/02/2022 à 18:59, Jonathan Cameron a écrit : > > >> On Wed, 9 Feb 2022 00:37:53 -0800 > > >> Qing Wang <wangqing-DGpbCiVdSXo@xxxxxxxxxxxxxxxx> wrote: > > >> > > >>> From: Wang Qing <wangqing-DGpbCiVdSXo@xxxxxxxxxxxxxxxx> > > >>> > > >>> do_div() does a 64-by-32 division. > > >>> When the divisor is u64, do_div() truncates it to 32 bits, this means it > > >>> can test non-zero and be truncated to zero for division. > > >>> > > >>> fix do_div.cocci warning: > > >>> do_div() does a 64-by-32 division, please consider using div64_u64 > > >>> instead. > > >>> > > >>> Signed-off-by: Wang Qing <wangqing-DGpbCiVdSXo@xxxxxxxxxxxxxxxx> > > >> These look correct to me. Jyoti, please could give these a sanity check? > > >> > > > > > > This is wrong. > > > > > > See [1]. > > > > > > CJ > > > > > > [1]: > > > https://lore.kernel.org/linux-kernel/20211117112559.jix3hmx7uwqmuryg-bIcnvbaLZ9MEGnE8C9+IrQ@xxxxxxxxxxxxxxxx/ > > > > Broken link, sorry: > > > > [1] > > https://lore.kernel.org/linux-kernel/20211117112559.jix3hmx7uwqmuryg@xxxxxxxxxxxxxx/ > > > oops. Thanks for the heads up. I'd forgotten the slightly odd convention > around do_div > > Jonathan > > > > > > > > > > >> Thanks, > > >> > > >> Jonathan > > >> > > >>> --- > > >>> drivers/iio/common/scmi_sensors/scmi_iio.c | 10 +++++----- > > >>> 1 file changed, 5 insertions(+), 5 deletions(-) > > >>> > > >>> diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c > > >>> b/drivers/iio/common/scmi_sensors/scmi_iio.c > > >>> index d538bf3..d6df5da > > >>> --- a/drivers/iio/common/scmi_sensors/scmi_iio.c > > >>> +++ b/drivers/iio/common/scmi_sensors/scmi_iio.c > > >>> @@ -160,7 +160,7 @@ static int scmi_iio_set_odr_val(struct iio_dev > > >>> *iio_dev, int val, int val2) > > >>> mult = scnprintf(buf, sizeof(buf), "%llu", sf) - 1; > > >>> sec = int_pow(10, mult) * UHZ_PER_HZ; > > >>> - do_div(sec, uHz); > > >>> + div64_u64(sec, uHz); > > >>> if (sec == 0) { > > >>> dev_err(&iio_dev->dev, > > >>> "Trying to set invalid sensor update value for sensor %s", > > >>> @@ -237,10 +237,10 @@ static void convert_ns_to_freq(u64 interval_ns, > > >>> u64 *hz, u64 *uhz) > > >>> u64 rem, freq; > > >>> freq = NSEC_PER_SEC; > > >>> - rem = do_div(freq, interval_ns); > > >>> + rem = div64_u64(freq, interval_ns); > > >>> *hz = freq; > > >>> *uhz = rem * 1000000UL; > > >>> - do_div(*uhz, interval_ns); > > >>> + div64_u64(*uhz, interval_ns); > > >>> } > > >>> static int scmi_iio_get_odr_val(struct iio_dev *iio_dev, int *val, > > >>> int *val2) > > >>> @@ -266,7 +266,7 @@ static int scmi_iio_get_odr_val(struct iio_dev > > >>> *iio_dev, int *val, int *val2) > > >>> mult = SCMI_SENS_CFG_GET_UPDATE_EXP(sensor_config); > > >>> if (mult < 0) { > > >>> sensor_interval_mult = int_pow(10, abs(mult)); > > >>> - do_div(sensor_update_interval, sensor_interval_mult); > > >>> + div64_u64(sensor_update_interval, sensor_interval_mult); > > >>> } else { > > >>> sensor_interval_mult = int_pow(10, mult); > > >>> sensor_update_interval = > > >>> @@ -500,7 +500,7 @@ static u64 scmi_iio_convert_interval_to_ns(u32 val) > > >>> mult = SCMI_SENS_INTVL_GET_EXP(val); > > >>> if (mult < 0) { > > >>> sensor_interval_mult = int_pow(10, abs(mult)); > > >>> - do_div(sensor_update_interval, sensor_interval_mult); > > >>> + div64_u64(sensor_update_interval, sensor_interval_mult); > > >>> } else { > > >>> sensor_interval_mult = int_pow(10, mult); > > >>> sensor_update_interval = > > >> > > >> > > > > > > > > >
