From: Liam Beguin Date: Sat, 8 Jan 2022 20:53:07 +0000 (-0500) Subject: iio: afe: rescale: use s64 for temporary scale calculations X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1cb35faea3c3ba101199b9e16561cc2328a985a1;p=linux.git iio: afe: rescale: use s64 for temporary scale calculations commit 51593106b608ae4247cc8da928813347da16d025 upstream. All four scaling coefficients can take signed values. Make tmp a signed 64-bit integer and switch to div_s64() to preserve signs during 64-bit divisions. Fixes: 8b74816b5a9a ("iio: afe: rescale: new driver") Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220108205319.2046348-5-liambeguin@gmail.com Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iio/afe/iio-rescale.c b/drivers/iio/afe/iio-rescale.c index 774eb3044edd8..271d73e420c42 100644 --- a/drivers/iio/afe/iio-rescale.c +++ b/drivers/iio/afe/iio-rescale.c @@ -39,7 +39,7 @@ static int rescale_read_raw(struct iio_dev *indio_dev, int *val, int *val2, long mask) { struct rescale *rescale = iio_priv(indio_dev); - unsigned long long tmp; + s64 tmp; int ret; switch (mask) { @@ -77,10 +77,10 @@ static int rescale_read_raw(struct iio_dev *indio_dev, *val2 = rescale->denominator; return IIO_VAL_FRACTIONAL; case IIO_VAL_FRACTIONAL_LOG2: - tmp = *val * 1000000000LL; - do_div(tmp, rescale->denominator); + tmp = (s64)*val * 1000000000LL; + tmp = div_s64(tmp, rescale->denominator); tmp *= rescale->numerator; - do_div(tmp, 1000000000LL); + tmp = div_s64(tmp, 1000000000LL); *val = tmp; return ret; default: