In case the result is -0.3252 tmp0 is 0 after the div_s64_rem, so tmp0 is non-negative which results in an output of 0.3252. Fix this by explicitly handling the negative sign ourselves. Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxxxxxxxx> --- drivers/iio/industrialio-core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 245b5844028d..18350c1959ae 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -568,6 +568,7 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type, { unsigned long long tmp; int tmp0, tmp1; + const char *sign = vals[0] < 0 ? "-" : ""; bool scale_db = false; switch (type) { @@ -593,11 +594,11 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type, tmp = 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)); + return snprintf(buf, len, "%s%u.%09u", sign, abs(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); - return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); + return snprintf(buf, len, "%s%u.%09u", sign, abs(tmp0), abs(tmp1)); case IIO_VAL_INT_MULTIPLE: { int i; -- 2.23.0