Re: [PATCH 3/3] power/ds2760_battery: use factor of 20 forrated_capacity

From: Anton Vorontsov
Date: Tue May 11 2010 - 13:47:52 EST


On Tue, May 11, 2010 at 07:25:29PM +0200, Daniel Mack wrote:
[...]
> > > /* Some batteries have their rated capacity stored a N * 10 mAh, while
> > > * others use an index into this table. */
> > > -#define RATED_CAPACITY_FACTOR 10
> > > +#define RATED_CAPACITY_FACTOR 20
> >
> > I'm a bit worried about this one.
> >
> > Shouldn't this confuse batteries that already store rated
> > capacity with factor of ten? If so, please introduce a module
> > option.
> >
> > Also, you don't update comments and module params description,
> > e.g.
> >
> > MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
> > ....
> > /* set rated capacity from module param (given in 10 * mAh) */
> >
> > Is that intentionally?
>
> Well, this parameter doesn't change, and hence the comment is left
> untouched. If it is passed as module option, it is interpreted as 10*mAh
> and converted to the internal value.
>
> You're right though about your concern about batteries that already
> stored a value given in mAh (and not as index) - this will break unless
> the module is loaded with a proper module parameter. Don't know whether
> this is acceptable.

Unfortunately, it is not. You have to do a run-time option, i.e.
module parameter (you can set up default value for this module
parameter via Kconfig symbol).

--
Anton Vorontsov
email: cbouatmailru@xxxxxxxxx
irc://irc.freenode.net/bd2
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