[ltp] Re: Generic battery interface

[Pavel Machek]

Hi!

> >Here's one approach: use a syscall (e.g., ioctl) saying "block until
> >there's new data on this fd, or N milliseconds have passed, whichever
> >is *later*". This way each client declares the update rate it wants
> >and can change it on the fly. The driver sees all the requests and can
> >perform the minimum hardware quering -- for example, it won't query
> >the hardware at all if no client has submitted a request with
> >parameter N more than N milliseconds go. And there's no excessive work
> >or interrupts. Some (simple) kernel code infrastructure is needed to
> >help drivers manage the pending requests.
> 
> Here's a rough sketch for the userspace side of a continuous function
> sampling interface. It handles the blocking a bit better than the
> above proposal, in that it lets you easily handle multiple readouts.
> It's agnostic about /dev vs. /sys.

Looks good to me.

> I'm not getting into the kernel side for now; it's doable, and with
> proper infrastructure (e.g., at the sysfs level) can be elegant and
> efficient.

I guess that hwmon people would like this, anyway...

Are there any plans at merging tp_smapi, BTW? After fixing few minor
details (like removing " mV" from files)... it looks like it would fit
into hwmon infrastructure rather nicely.
								Pavel
-- 
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