On Mon, Nov 26, 2018 at 06:30:04PM -0800, Linus Torvalds wrote: > On Thu, Nov 22, 2018 at 3:28 PM Peter Hutterer <peter.hutterer@xxxxxxxxx> wrote: > > > > The device sends hi-res values of 4, so it should end up as REL_WHEEL_HI_RES > > 30. We are getting 28 instead which doesn't add up to a nice 120. > > I think you're just doing the math in the wrong order. > > Why don't you just do > > update = val * 120 / multiplier > > which gives you the expected "30". > > It seems you have done the "120 / multiplier" too early, and you force > that value into "wheel_factor". Don't. Do all the calculations > (including all the accumulated ones) in the original values, and only > do the "multiply by 120 and divide by multiplier" at the very end. that's such a simple solution that it almost explains why I didn't think of it... Thanks! Cheers, Peter
