diff options
| author | Gregor Boirie <gregor.boirie@parrot.com> | 2016-09-02 20:27:46 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-09-24 10:07:38 +0200 |
| commit | dd1e7b2406492f2fc833a148d470fbc4abb5b45e (patch) | |
| tree | 1bfc5f7ad541c1806a3d4d4fba0fcf1e67c63bb5 /drivers | |
| parent | 2157e3380858613d70037b0d4c3448a694a7e458 (diff) | |
iio:core: fix IIO_VAL_FRACTIONAL sign handling
commit 171c0091837c81ed5c949fec6966bb5afff2d1cf upstream.
7985e7c100 ("iio: Introduce a new fractional value type") introduced a
new IIO_VAL_FRACTIONAL value type meant to represent rational type numbers
expressed by a numerator and denominator combination.
Formating of IIO_VAL_FRACTIONAL values relies upon do_div() usage. This
fails handling negative values properly since parameters are reevaluated
as unsigned values.
Fix this by using div_s64_rem() instead. Computed integer part will carry
properly signed value. Formatted fractional part will always be positive.
Fixes: 7985e7c100 ("iio: Introduce a new fractional value type")
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/iio/industrialio-core.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 159ede61f793..7ede941e9301 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -447,9 +447,8 @@ ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals) return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); case IIO_VAL_FRACTIONAL: tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]); - vals[1] = do_div(tmp, 1000000000LL); - vals[0] = tmp; - return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); + vals[0] = (int)div_s64_rem(tmp, 1000000000, &vals[1]); + return sprintf(buf, "%d.%09u\n", vals[0], abs(vals[1])); case IIO_VAL_FRACTIONAL_LOG2: tmp = (s64)vals[0] * 1000000000LL >> vals[1]; vals[1] = do_div(tmp, 1000000000LL); |