[ltp] Re: [PATCH v2] Re: Battery class driver.

[Shem Multinymous]

Hi Greg,

On 11/1/06, Greg KH <greg@kroah.com> wrote:
> > The suggestions so far were:
> > 1. Append units string to the content of such attribute:
> >   /sys/.../capacity_remaining reads "16495 mW".
> > 2. Add a seprate *_units attribute saying what are units for other
> > attribute:
> >   /sys/.../capacity_units gives the units for
> >   /sys/.../capacity_{remaining,last_full,design,min,...}.
> > 3. Append the units to the attribute names:
> >   capacity_{remaining,last_full,design_min,...}:mV.
>
> No, again, one for power and one for current.  Two different files
> depending on the type of battery present.  That way there is no need to
> worry about unit issues.

I'm missing something. How is that different from option 3 above?
BTW, please note that we're talking about a large set of files that
use these units (remaining, last full, design capacity, alarm
thresholds, etc.), and not just a single attribute.

This particular alternative indeed seems cleanest for the kernel side.
The drawback is that someone in userspace who doesn't care about units
but just wants to show a status report or compute the amount of
remaining fooergy divided by the amount of a fooergy when fully
charged, like your typical battery applet, will need to parse
filenames (or try out a fixed and possibly partial list) to find out
which attribute files contain the numbers.

  Shem