Re: [PATCH 10/13] twl4030_charger: add software controlled linear charging mode.

From: Pavel Machek
Date: Tue Sep 15 2015 - 07:28:31 EST


On Thu 2015-07-30 10:11:24, NeilBrown wrote:
>
> Add a 'continuous' option for usb charging which enables
> the "linear" charging mode of the twl4030.
>
> Linear charging does a good job with not-so-reliable power sources.
> Auto mode does not work well as it switches off when voltage drops
> momentarily. Care must be taken not to over-charge.

Can you explain how the user can "care not to over-charge"?

> @@ -750,6 +784,17 @@ static int twl4030_bci_get_property(struct power_supply *psy,
> is_charging = state & TWL4030_MSTATEC_USB;
> else
> is_charging = state & TWL4030_MSTATEC_AC;
> + if (!is_charging) {
> + u8 s;
> + twl4030_bci_read(TWL4030_BCIMDEN, &s);
> + if (psy->desc->type == POWER_SUPPLY_TYPE_USB)
> + is_charging = s & 1;
> + else
> + is_charging = s & 2;
> + if (is_charging)
> + /* A little white lie */
> + state = TWL4030_MSTATEC_QUICK1;

I'm not sure... can't this white lie turn into black smoke?

Like.. normally, when battery is below something (like 3.5V) it must
not be quick-charged (because something is very wrong with it). Are
you just forcing the quick charge here?

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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