On Thu, 20 Aug 2020 11:09:44 -0700 Anand Ashok Dumbre <[email protected]> wrote:
> This patch fixes IIO_VAL_FRACTIONAL calculation for negative > values where the exponent is 0. > > Signed-off-by: Anand Ashok Dumbre <[email protected]> Hi, I would thrown in an example for this description. Also useful to know if there is a existing driver that is broken and hence we need to backport this. If that is the case, please try to figure out an appropriate fixes tag. Comments inline + the email footer issue needs sorting out. Thanks, Jonathan > --- > drivers/iio/industrialio-core.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c > index f72c2dc..cd43b17 100644 > --- a/drivers/iio/industrialio-core.c > +++ b/drivers/iio/industrialio-core.c > @@ -554,6 +554,7 @@ static ssize_t __iio_format_value(char *buf, size_t len, > unsigned int type, > { > unsigned long long tmp; > int tmp0, tmp1; > + s64 tmp2; > bool scale_db = false; > > switch (type) { > @@ -576,10 +577,13 @@ static ssize_t __iio_format_value(char *buf, size_t > len, unsigned int type, > else > return snprintf(buf, len, "%d.%09u", vals[0], > vals[1]); > case IIO_VAL_FRACTIONAL: > - tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]); > + tmp2 = div_s64((s64)vals[0] * 1000000000LL, vals[1]); > tmp1 = vals[1]; > - tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1); > - return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); > + tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1); > + if ((tmp2 < 0) && (tmp0 == 0)) > + return snprintf(buf, len, "-%d.%09u", tmp0, > abs(tmp1)); Given tmp0 == 0, this might be clearer as return snprintf(buf, len, "-0.%09u", abs(tmp1)); > + else > + return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); > case IIO_VAL_FRACTIONAL_LOG2: > tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]); > tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1); > -- > 2.7.4 > > This email and any attachments are intended for the sole use of the named > recipient(s) and contain(s) confidential information that may be proprietary, > privileged or copyrighted under applicable law. If you are not the intended > recipient, do not read, copy, or forward this email message or any > attachments. Delete this email message and any attachments immediately. As Andy said, this footer is a problem...
