BQ25895: Why bq25890_charger.ko linux kernel module not update itself automatically when USB is connected / disconnected

Krzysztof Bracha

Part Number: BQ25895
Other Parts Discussed in Thread: BQ25890,

Tool/software:

Please see the output below.

When the kernel module is reloaded, depending on whether the USB is connected or not, it updates few of the values (POWER_SUPPLY_ONLINE, POWER_SUPPLY_STATUS, POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE).

However, unless it is reloaded it seems that these values never update.

Could you advise why the driver may not be updating the values automatically?

$ modinfo -F filename bq25890_charger
/lib/modules/4.4.194/bq25890_charger.ko
$ cat /sys/class/power_supply/bq25890-charger/uevent
POWER_SUPPLY_NAME=bq25890-charger
POWER_SUPPLY_MANUFACTURER=Texas Instruments
POWER_SUPPLY_MODEL_NAME=BQ25895
POWER_SUPPLY_STATUS=Full
POWER_SUPPLY_CHARGE_TYPE=N/A
POWER_SUPPLY_ONLINE=1
POWER_SUPPLY_HEALTH=Good
POWER_SUPPLY_CONSTANT_CHARGE_CURRENT_MAX=1088000
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE=2304000
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE_MAX=4208000
POWER_SUPPLY_CHARGE_TERM_CURRENT=64000
POWER_SUPPLY_INPUT_CURRENT_LIMIT=2100000
POWER_SUPPLY_VOLTAGE_NOW=2304000
POWER_SUPPLY_CURRENT_NOW=0
$ echo "Disconnect USB and wait 10 seconds"
Disconnect USB and wait 10 seconds
$ cat /sys/class/power_supply/bq25890-charger/uevent
POWER_SUPPLY_NAME=bq25890-charger
POWER_SUPPLY_MANUFACTURER=Texas Instruments
POWER_SUPPLY_MODEL_NAME=BQ25895
POWER_SUPPLY_STATUS=Full
POWER_SUPPLY_CHARGE_TYPE=N/A
POWER_SUPPLY_ONLINE=1
POWER_SUPPLY_HEALTH=Good
POWER_SUPPLY_CONSTANT_CHARGE_CURRENT_MAX=1088000
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE=2304000
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE_MAX=4208000
POWER_SUPPLY_CHARGE_TERM_CURRENT=64000
POWER_SUPPLY_INPUT_CURRENT_LIMIT=2100000
POWER_SUPPLY_VOLTAGE_NOW=2304000
POWER_SUPPLY_CURRENT_NOW=0
$ sudo rmmod bq25890_charger
$ sudo insmod bq25890_charger.ko
$ cat /sys/class/power_supply/bq25890-charger/uevent
POWER_SUPPLY_NAME=bq25890-charger
POWER_SUPPLY_MANUFACTURER=Texas Instruments
POWER_SUPPLY_MODEL_NAME=BQ25895
POWER_SUPPLY_STATUS=Discharging
POWER_SUPPLY_CHARGE_TYPE=N/A
POWER_SUPPLY_ONLINE=0
POWER_SUPPLY_HEALTH=Good
POWER_SUPPLY_CONSTANT_CHARGE_CURRENT_MAX=1088000
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE=0
POWER_SUPPLY_CONSTANT_CHARGE_VOLTAGE_MAX=4208000
POWER_SUPPLY_CHARGE_TERM_CURRENT=64000
POWER_SUPPLY_INPUT_CURRENT_LIMIT=2100000
POWER_SUPPLY_VOLTAGE_NOW=2304000
POWER_SUPPLY_CURRENT_NOW=0

26 days ago

0 Ning T 25 days ago

TI__Guru 51941 points

Hi,

Did you make the driver or get it somewhere else?

Thanks,

Ning

0 Krzysztof Bracha 25 days ago in reply to Ning T

Prodigy 10 points

Hello

We build the driver via buildroot, it should be the same as in the kernel version 4.4.194

Regards,

Krzysztof

0 Ning T 25 days ago in reply to Krzysztof Bracha

TI__Guru 51941 points

Hi Krzysztof,

We are unable to debug the driver code. Please refer to the link below for available driver resources as reference.

https://github.com/tibms?tab=repositories

Thanks,

Ning.

0 Krzysztof Bracha 24 days ago in reply to Ning T

Prodigy 10 points

Hello

I am sorry but I am not sure how I can resolve the problem with the repository linked. I have a few questions:

1) Could you advise what is that repository, who is the owner and what it contains?

2) Does it have a Linux driver that we could use for reading/control of BQ25895?

3) Why are you unable to debug the driver code, i.e. is the official Linux driver for the chip not supported by you?

Kind regards,

Krzysztof

0 Wyatt Keller 24 days ago in reply to Krzysztof Bracha

TI__Guru** 104010 points

Hello Krzysztof,

We don't actively support the Linux drivers, many of our chargers including BQ25890 are incorporated into the mainline and we have not gotten reports of any issues with this driver. The drivers are provided as reference.

Sincerely,

Wyatt Keller

0 Krzysztof Bracha 1 day ago

Prodigy 10 points

The driver relies on receiving an interrupt from the chip on status / state changes, see the bq25890_probe() / devm_request_threaded_irq() methods and the datasheet.

We confirmed with our HW supplier that the interrupt connection is not working as expected and therefore explained the root cause of the problem.

Power management

Power management forum

BQ25895: Why bq25890_charger.ko linux kernel module not update itself automatically when USB is connected / disconnected