diff options
| author | Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com> | 2020-10-05 18:05:16 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2020-10-10 19:52:34 +0300 |
| commit | 0e7a3978a40b26b85820afe9e544f0032103f805 (patch) | |
| tree | 92c23241fd78080c32b9620bbde231e2081d3a0c /drivers/iio/industrialio-core.c | |
| parent | c5bf4d645f2d5c4c216dd690c5237d778102c848 (diff) | |
| download | linux-0e7a3978a40b26b85820afe9e544f0032103f805.tar.xz | |
iio: core: Fix IIO_VAL_FRACTIONAL calculation for negative values
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.
Reported-by: kernel test robot <lkp@intel.com> #error: uninitialized symbol tmp
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
Link: https://lore.kernel.org/r/1601910316-24111-1-git-send-email-anand.ashok.dumbre@xilinx.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/industrialio-core.c')
| -rw-r--r-- | drivers/iio/industrialio-core.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 261d3b17edc9..9955672fc16a 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -594,6 +594,7 @@ 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) { @@ -616,10 +617,13 @@ 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); |