Re: [PATCH v2 08/13] power: bq24257: Add charge type setting support

Andreas Dannenberg
2015-09-10T18:51:00Z

On Thu, Sep 10, 2015 at 04:56:22PM +0300, Laurentiu Palcu wrote:
> On Tue, Sep 08, 2015 at 07:12:32PM -0500, Andreas Dannenberg wrote:
> > The bq2425x devices support charging with a configurable charge current
> > i_chg or a specific fixed low-current in what's called Low Charge mode.
> > This patch exposes access to the Low Charge mode through a POWER_
> > SUPPLY_PROP_CHARGE_TYPE sysfs property value of POWER_SUPPLY_CHARGE_
> > TYPE_TRICKLE. It also allows to completely disable charging if desired
> > by setting the property to POWER_SUPPLY_CHARGE_TYPE_NONE. Normal
> > charging with the configured i_chg current is activated through
> > POWER_SUPPLY_CHARGE_TYPE_FAST (default).
> >
> > Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
>
> I have some questions here. Are there any cases in the wild, when
> userspace selects the charging type (apart from testing purposes)? And
> if yes, how is userspace supposed to detect/decide when to switch from
> trickle to fast?
>
> I have the strange feeling that we're adding properties that will never
> be used... Other people's opinions are welcomed too.

Hi Laurentiu. I just talked to our product people to see as to how the
underlying LOW_CHG feature would be used and they essentially said its a
legacy feature used by only one customer in the past and that it doesn't
need to get exposed in our driver. I had initially implemented it in
analogy with the bq24190_charger.c driver that exposes a somewhat
similar feature but if nobody needs it from a TI point of view I'm ok
dropping it. Unless somebody screams they want it :)

Regards,

--
Andreas Dannenberg
Texas Instruments Inc

>
> laurentiu