Re: [PATCH 2/2] power: supply: qcom_battmgr: expose CHARGE_NOW on SM8350-class firmware

[Jan-Michael Brummer <jan.brummer@tabos.org>]

Am Mittwoch, dem 02.09.2026 um 18:21 +0200 schrieb Konrad Dybcio:
> On 9/2/26 5:02 PM, Konrad Dybcio wrote:
> > On 8/29/26 7:45 AM, Jan-Michael Brummer wrote:
> > > The SM8350-class firmware does not implement a dedicated 'charge
> > > now'
> > > property. It does however report BATT_CHG_COUNTER, and on this
> > > class of
> > > firmware that value is the remaining charge in uAh rather than a
> > > monotonic counter. Measured on a Fairphone 5 with charge_full at
> > > 4116000 uAh:
> > > 
> > >   BATT_CHG_COUNTER   reported capacity   counter / charge_full
> > >   2434614            59%                 59.1%
> > >   3525354            85%                 85.6%
> > > 
> > > Map POWER_SUPPLY_PROP_CHARGE_NOW onto the same firmware property
> > > and
> > > store the value in status.capacity, which the
> > > CHARGE_NOW/ENERGY_NOW case
> > > of qcom_battmgr_bat_get_property() already reads.
> > > 
> > > Together with the preceding patch this gives userspace both the
> > > full
> > > charge and the current charge. UPower now derives an energy level
> > > and
> > > runtime estimates in both directions:
> > > 
> > >     state:               discharging      state:              
> > > charging
> > >     energy:              14.4347 Wh       energy:             
> > > 15.6003 Wh
> > >     energy-full:         16.8807 Wh       energy-full:        
> > > 18.1505 Wh
> > >     energy-rate:         3.39313 W        energy-rate:        
> > > 7.3492 W
> > >     time to empty:       4.3 hours        time to full:       
> > > 20.8 minutes
> > > 
> > > Signed-off-by: Jan-Michael Brummer <jan.brummer@tabos.org>
> > > ---
> > 
> > Ok this makes more sense now. We should still gate the other
> > property though.

Hi Konrad,

so this one is fine and can be merged? Or am i'm missing something?

> > 
> > [...]
> > 
> > > @@ -1442,7 +1445,10 @@ static void
> > > qcom_battmgr_sm8350_callback(struct qcom_battmgr *battmgr,
> > >  			battmgr->info.technology =
> > > le32_to_cpu(resp->intval.value);
> > >  			break;
> > >  		case BATT_CHG_COUNTER:
> > > -			battmgr->info.charge_count =
> > > le32_to_cpu(resp->intval.value);
> > > +			val = le32_to_cpu(resp->intval.value);
> > > +			battmgr->info.charge_count = val;
> > > +			/* the firmware reports the remaining
> > > charge here */
> > > +			battmgr->status.capacity = val;
> > 
> > Let me try and find whether we can rely on this - on newer targets
> > many properties are more or less just front-ends for vendor
> > plumbing (because there's a ton of different chargers etc.)
> 
> There's a comment saying /* remaining capacity in uAh */, so it seems
> like this should be OK
> 
> Konrad