Hi Geert-san, > From: Geert Uytterhoeven, Sent: Monday, June 3, 2019 8:05 PM <snip> > > > > +{ > > > > + unsigned long periods, delays; > > > > + > > > > + periods = DIV_ROUND_UP(priv->clk_rate, cycles); > > > > > > Shouldn't the above be a division with rounding down (i.e. a plain C > > > division), instead of a division with rounding up? > > > > I have no idea which is the correct way (rounding down vs rounding up here). > > At least, I tried to use rounding down before submitting patch and then > > the result seemed the same. So, I submitted this patch with rounding up > > (because the next step also used rounding up...). > > If you round up periods, it will decrease the delay, which may become > too small. > If you round up delays, it will increase the delay, which doesn't hurt. Thank you for your explanation in detail! I understood it. Best regards, Yoshihiro Shimoda