Fixes IIO_VAL_FRACTIONAL for case when the result is negative and exponent is 0.
example: if the result is -0.75, tmp0 will be 0 and tmp1 = 75 This causes the output to lose sign because of %d in snprintf which works for tmp0 <= -1. Signed-off-by: Anand Ashok Dumbre <[email protected]> Reported-by: kernel test robot <[email protected]> #error: uninitialized symbol tmp Reported-by: Dan Carpenter <[email protected]> --- Changes in v3: Fixed a bug caught by kernel test robot and used correct variable --- 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 cdcd16f1..ffd5176 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -592,6 +592,7 @@ 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) { @@ -614,10 +615,13 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type, else return scnprintf(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 scnprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); + tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1); + if ((tmp2 < 0) && (tmp0 == 0)) + 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
