Re: Generic battery interface

Vojtech Pavlik
2006-07-28T10:11:58Z

On Fri, Jul 28, 2006 at 03:35:10AM +0300, Shem Multinymous wrote:
> On 7/28/06, Vojtech Pavlik <vojtech@suse.cz> wrote:
> > note: It's absolutely necessary to limit the API to a well usable
> > SUBSET of a superset of the features of all drivers/devices,
> > even sacrificing obscure features to keep the API sane. One
> > example would be the HID Power spec, which simply can't be
> > supported to full extent by any sane API.
>
> Non-standard functions must be handled reasonably within the
> framework, otherwise drivers will have to build duplicate interfaces.
>
> How about
> /sys/whatever/battery0/voltage for standard attributes
> and
> /sys/whatever/battery0/thinkpad/inhibit-charge-minutes
> for non-standard ones?

I think the thinkpad features actually fall into the 'standard API', if
not for any other reason, then because some 80% of kernel developers use
ThinkPads. ;)

> > + and the kernel can change the polling frequency based on power
> > saving state changes
>
> Likewise for cached attributes (query hardware only if N jiffies
> passed since last querry, other return cached value). And that way,
> hardware query frequency is never higher than what userspace actually
> needs.

--
Vojtech Pavlik
Director SuSE Labs