On Fri, Sep 28, 2018 at 04:00:17PM +0200, Hans Verkuil wrote: > On 09/25/2018 12:14 PM, Sakari Ailus wrote: > > +/* V4L2 control unit prefixes */ > > +#define V4L2_CTRL_PREFIX_NANO -9 > > +#define V4L2_CTRL_PREFIX_MICRO -6 > > +#define V4L2_CTRL_PREFIX_MILLI -3 > > +#define V4L2_CTRL_PREFIX_1 0 > > I would prefer PREFIX_NONE, since there is no prefix in this case. > > I assume this prefix is only valid if the unit is not UNDEFINED and not > NONE? Why should it? The prefix is concerned with rescaling a value prior to presenting it to a user. Even a unitless quantity or a value of undefined unit can be reasonably scaled. Displaying a unit and scaling look like orthogonal concepts to me. > Is 'base' also dependent on a valid unit? (it doesn't appear to be) I'd argue it should not depend on a valid unit like the prefix. Helmut
