On 02/04/17 11:09, Lars-Peter Clausen wrote: > On 04/02/2017 11:26 AM, Jonathan Cameron wrote: >> On 25/03/17 18:03, Jonathan Cameron wrote: >>> On 24/03/17 12:41, Nikolaus Schulz wrote: >>>> 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 <nikolaus.schulz@xxxxxxxxxxxxxxxxx> >>>> Cc: stable@xxxxxxxxxxxxxxx >>> Looks sane to me, but I'd like to give others time to comment on this >>> just in case there is some odd condition neither of us has thought of! >>> >>> Give me a poke if we get nothing else for a few weeks. >> Lars, I think this might have been your magic in the first place. >> >> Could you sanity check this one please. It's in the category of very >> risky of both Nikolaus and I have missed something! > > It's the same as this: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/iio/industrialio-core.c?id=171c0091837c81ed5c949fec6966bb5afff2d1cf > > Should be OK. > > Reviewed-by: Lars-Peter Clausen <lars@xxxxxxxxxx> Good point. I'd not thought to check and had forgotten that one. Applied to the fixes-togreg branch. Thanks, Jonathan > >> >> Thanks, >> >> Jonathan >>> >>> Jonathan >>>> --- >>>> 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 d18ded4..3ff91e0 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; >>>> >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >