On 05/09/16 08:59, Lars-Peter Clausen wrote: > On 09/03/2016 05:13 PM, Jonathan Cameron wrote: >> On 02/09/16 19:27, Gregor Boirie wrote: >>> 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@xxxxxxxxxx> >> >> Hi Gregor, >> >> While this looks sensible to me, I always gain an almighty headache when >> I hit the various divide functions. >> >> Lars, the fractional code was yours in the first place. >> If you have time can you sanity check this please. > > Looks good. While looking into this I noticed that we have a very similar > patch[1] in our tree, seems like somebody forgot to send that upstream. > > Reviewed-by: Lars-Peter Clausen <lars@xxxxxxxxxx> Applied to the fixes-togreg branch of iio.git and marked for stable. Good to know about the previous patch - if there was anything hiding around this I would assume that would have shaken it out by now! Thanks Jonathan > > > [1] > https://github.com/analogdevicesinc/linux/commit/1dbcdcfd0c8d3f5513572697685d9f30ba49d851 > > -- > 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