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]>
---
changes since v1:
        Changed -%d to -0 to make the fix clearer.
        Removed the email footer.
        Updated the commit description with an example
--
 drivers/iio/industrialio-core.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index cdcd16f1..a239fa2 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));
+               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

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