Re: dt-bindings: power: supply: bq27xxx: Add monitored-battery documentation

From: H. Nikolaus Schaller
Date: Tue Aug 29 2017 - 16:09:53 EST


Hi,

> Am 29.08.2017 um 22:05 schrieb Liam Breck <liam@xxxxxxxxxxxxxxxxx>:
>
> Hi,
>
> On Tue, Aug 29, 2017 at 12:50 PM, H. Nikolaus Schaller
> <hns@xxxxxxxxxxxxx> wrote:
>> Hi Liam,
>>
>>> Am 29.08.2017 um 20:18 schrieb Liam Breck <liam@xxxxxxxxxxxxxxxxx>:
>>>
>>> Hi Nikolaus, thanks for the testing report...
>>>
>>> On Tue, Aug 29, 2017 at 7:24 AM, H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> wrote:
>>>> Hi Liam,
>>>> seems to work as expected :)
>>>>
>>>> First boot:
>>>>
>>>> [ 6.096336] bq27xxx_battery_settings
>>>> [ 6.097987] bq27xxx_battery_set_config
>>>> [ 6.097990] bq27xxx_battery_unseal
>>>> [ 6.107987] bq27xxx-battery 1-0055: update design-capacity to 6000
>>>> [ 6.107992] bq27xxx-battery 1-0055: update design-energy to 22200
>>>> [ 6.107997] bq27xxx-battery 1-0055: terminate-voltage has 3200
>>>> [ 6.382048] bq27xxx-battery 1-0055: cfgupdate 0, retries 7
>>>> [ 6.382054] bq27xxx_battery_seal
>>>>
>>>> Second boot (w/o removing battery in between):
>>>>
>>>> [ 6.008883] bq27xxx_battery_settings
>>>> [ 6.013280] bq27xxx_battery_set_config
>>>> [ 6.018761] bq27xxx_battery_unseal
>>>> [ 6.050694] bq27xxx-battery 1-0055: design-capacity has 6000
>>>> [ 6.059913] bq27xxx-battery 1-0055: design-energy has 22200
>>>> [ 6.067113] bq27xxx-battery 1-0055: terminate-voltage has 3200
>>>> [ 6.075803] bq27xxx_battery_seal
>>>
>>> I'd be interested to hear what happens after poweroff & boot (ie does
>>> it retain config)?
>>
>> second boot was simple poweroff + reboot and it changes from "update design-capacity" to "design-capacity has"
>> which IMHO means that the bq27421 did retain settings and was therefore not reprogrammed.
>
> That implies that the board is keeping the battery gauge powered
> during poweroff.

Yes, that is how hardware is designed on this system.

> That's not a problem per se, but could indicate that
> other subsystems are also powered...

Well, the power controller (Palmas) stays powered to respond to the power-on-key...

Therefore I completely removed all power as well.

>
>>>
>>>> Third boot (with removing battery in between):
>>>>
>>>> [ 6.161085] bq27xxx_battery_settings
>>>> [ 6.161162] bq27xxx_battery_set_config
>>>> [ 6.161165] bq27xxx_battery_unseal
>>>> [ 6.177904] bq27xxx-battery 1-0055: update design-capacity to 6000
>>>> [ 6.177909] bq27xxx-battery 1-0055: update design-energy to 22200
>>>> [ 6.177914] bq27xxx-battery 1-0055: terminate-voltage has 3200
>>>> [ 6.440592] bq27xxx-battery 1-0055: cfgupdate 0, retries 7
>>>> [ 6.440597] bq27xxx_battery_seal
>>
>> this was with removing all power which makes the bq27421 loosing the settings.
>> And next reboot does another "update design-capacity".
>>
>>>>
>>>> (I have added some printk to trace seal/unseal etc.)
>>>>
>>>> Values match the 6000mAh specified by DT:
>>>>
>>>> bat: battery {
>>>> compatible = "simple-battery", "pyra-battery";
>>>> voltage-min-design-microvolt = <3200000>;
>>>> energy-full-design-microwatt-hours = <22200000>;
>>>> charge-full-design-microamp-hours = <6000000>;
>>>> };
>>>>
>>>> root@letux:~# cat /sys/class/power_supply/bq27421-0/uevent
>>>> POWER_SUPPLY_NAME=bq27421-0
>>>> POWER_SUPPLY_STATUS=Discharging
>>>> POWER_SUPPLY_PRESENT=1
>>>> POWER_SUPPLY_VOLTAGE_NOW=3943000
>>>> POWER_SUPPLY_CURRENT_NOW=-634000
>>>> POWER_SUPPLY_CAPACITY=82
>>>> POWER_SUPPLY_CAPACITY_LEVEL=Normal
>>>> POWER_SUPPLY_TEMP=319
>>>> POWER_SUPPLY_TECHNOLOGY=Li-ion
>>>> POWER_SUPPLY_CHARGE_FULL=5467000
>>>> POWER_SUPPLY_CHARGE_NOW=4611000
>>>> POWER_SUPPLY_CHARGE_FULL_DESIGN=6000000
>>>> POWER_SUPPLY_MANUFACTURER=Texas Instruments
>>>> root@letux:~#
>>>>
>>>> Anything else I should test?
>>>
>>> Could you also test voltage-min-design-microvolt at 3177 to make sure
>>> that's configurable too?
>>
>> Yes:
>>
>> bat: battery {
>> compatible = "simple-battery", "pyra-battery";
>> voltage-min-design-microvolt = <3177000>;
>> energy-full-design-microwatt-hours = <22200000>;
>> charge-full-design-microamp-hours = <6000000>;
>> };
>>
>> gives
>>
>> [ 6.241009] bq27xxx_battery_settings
>> [ 6.241055] bq27xxx_battery_set_config
>> [ 6.241058] bq27xxx_battery_unseal
>> [ 6.257073] bq27xxx-battery 1-0055: update design-capacity to 6000
>> [ 6.257078] bq27xxx-battery 1-0055: update design-energy to 22200
>> [ 6.257084] bq27xxx-battery 1-0055: update terminate-voltage to 3177
>> [ 6.379230] bq27xxx_battery_seal
>>
>> So it looks good.
>
> \o/
>
>>> Sebastian just queued my series to -next. Would you be inclined to
>>> submit a new patch enabling bq27421? If so, the sooner the better
>>> since merge window is imminent :-)
>>
>> I already have a patch for that...
>
> Peering eagerly at linux-pm for said patch...

Seems to have been lost on first attempt. Will resend in some minutes.

BR,
Nikolaus