Re: [PATCH 3/4] power: supply: mm8013: implement POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR_AVAILABLE

From: Thomas Weißschuh
Date: Mon Feb 05 2024 - 06:22:09 EST


On 2024-02-05 11:00:01+0100, Hans de Goede wrote:
> Hi,
>
> On 2/4/24 18:26, Thomas Weißschuh wrote:
> > The sysfs is documented to report both the current and all available
> > behaviours. For this POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR_AVAILABLE needs
> > to be implemented.
> >
> > Note that this changes the format of the sysfs file
> > (to the documented format):
> >
> > Before: "auto"
> > After: "[auto] inhibit-charge"
> >
> > Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
>
> Changing userspace API like this is never ideal, but given how
> new the mm8013 driver is and that this brings things inline
> with the docs I think that this should be fine:

I agree that it's unfortunate.

However looking at the datasheet [0] it seems to me the driver is
not correctly using the API.

Page 23 documents the flag CHG_INH as follows:

CHG_INH : Charge Inhibit When the current is more than or equal to charge
threshold current,
charge inhibit temperature (upper/lower limit) :1
charge permission temperature or the current is
less than charge threshold current :0

This is only diagnostic information and not a control-knob, which the API
was meant for.
So POWER_SUPPLY_STATUS_NOT_CHARGING seems like the better match.

> [..]

Thomas


[0] https://product.minebeamitsumi.com/en/product/category/ics/battery/fuel_gauge/parts/download/__icsFiles/afieldfile/2023/07/12/1_download_01_12.pdf