From 7fd6592d1287046f61bfd3cda3c03cd35be490f7 Mon Sep 17 00:00:00 2001 From: Nikolaus Schulz Date: Fri, 24 Mar 2017 13:41:51 +0100 Subject: [PATCH] iio: core: Fix IIO_VAL_FRACTIONAL_LOG2 for negative values Fix formatting of negative values of type IIO_VAL_FRACTIONAL_LOG2 by switching from do_div(), which can't handle negative numbers, to div_s64_rem(). Also use shift_right for shifting, which is safe with negative values. Signed-off-by: Nikolaus Schulz Reviewed-by: Lars-Peter Clausen Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-core.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index d18ded45bedd..3ff91e02fee3 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -610,10 +610,9 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type, tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1); return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); case IIO_VAL_FRACTIONAL_LOG2: - tmp = (s64)vals[0] * 1000000000LL >> vals[1]; - tmp1 = do_div(tmp, 1000000000LL); - tmp0 = tmp; - return snprintf(buf, len, "%d.%09u", tmp0, tmp1); + tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]); + tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1); + return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); case IIO_VAL_INT_MULTIPLE: { int i; -- 2.20.1