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 <anand.ashok.dumbre@xxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx> #error: uninitialized symbol tmp
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
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
