`On Mon, Jun 07, 2021 at 05:24:44PM +0300, Andy Shevchenko wrote:> On Mon, Jun 07, 2021 at 03:33:31PM +0300, Jarkko Nikula wrote:> > On 6/3/21 7:04 PM, Andy Shevchenko wrote:> > > Sometimes it's useful to have well-defined SI metric prefix to be used> > > to self-describe the formulas or equations.> > > > > > List most popular ones in the units.h.> > ...> > > > +/* Metric prefixes in accordance with Système international (d'unités) */> > > +#define PETA	1000000000000000LL> > > +#define TERA	1000000000000LL> > > +#define GIGA	1000000000L> > > +#define MEGA	1000000L> > > +#define KILO	1000L> > > +#define HECTO	100L> > > +#define DECA	10L> > > +#define DECI	10L> > > +#define CENTI	100L> > > +#define MILLI	1000L> > > +#define MICRO	1000000L> > > +#define NANO	1000000000L> > > +#define PICO	1000000000000LL> > > +#define FEMTO	1000000000000000LL> > > > For me milli is always 1/1000.> > For me as well. Kernel does not operate with float point numbers.> That's why it's ordered like this.> > > Might lead to confusion with these defines if> > idea is to multiply with KILO but divide with MILLI?> > If the author of the hypothetical driver doesn't understand this, maybe> they can ask first, but I am an optimist here and I assume that whoever> writes the driver for a sensor / etc has a minimum education to see> what's needed for the certain case.Writing this, I think that I'm not so educated :-)What we have in I²C case is kHz * ns = 10^3 * 10^-9, so we need to divide by10^-6 to normalize the numbers. Sounds like MICRO is the correct thing to usethere.-- With Best Regards,Andy Shevchenko`