Hi,

On Tue, Aug 01, 2017 at 10:55:26PM +0200, Marek Belisko wrote:
> From: Marek Belisko <marek.belisko@gmail.com>
> 
> Signed-off-by: Marek Belisko <marek.belisko@gmail.com>
> ---
>  drivers/power/supply/generic-adc-battery.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/power/supply/generic-adc-battery.c b/drivers/power/supply/generic-adc-battery.c
> index 0d27b59..9ce51d2 100644
> --- a/drivers/power/supply/generic-adc-battery.c
> +++ b/drivers/power/supply/generic-adc-battery.c
> @@ -24,6 +24,7 @@
>  #include <linux/iio/types.h>
>  #include <linux/power/generic-adc-battery.h>
>  #include <linux/of_gpio.h>
> +#include <linux/power/generic-fuel-gauge.h>
>  
>  #define JITTER_DEFAULT 10 /* hope 10ms is enough */
>  
> @@ -81,6 +82,7 @@ static const enum power_supply_property gab_props[] = {
>  	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
>  	POWER_SUPPLY_PROP_MODEL_NAME,
>  	POWER_SUPPLY_PROP_TEMP,
> +	POWER_SUPPLY_PROP_CAPACITY,
>  };
>  
>  /*
> @@ -202,6 +204,18 @@ static int gab_get_property(struct power_supply *psy,
>  	case POWER_SUPPLY_PROP_MODEL_NAME:
>  		val->strval = bat_info->name;
>  		break;
> +	case POWER_SUPPLY_PROP_CAPACITY:
> +		{
> +		int ret, curr, voltage;
> +
> +		ret = read_channel(adc_bat, POWER_SUPPLY_PROP_CURRENT_NOW, &curr);
> +		ret |= read_channel(adc_bat, POWER_SUPPLY_PROP_VOLTAGE_NOW, &voltage);
> +		if (ret < 0)
> +			goto err;
> +
> +		val->intval = fuel_level_LiIon(voltage, curr, 10);
> +		}
> +		break;
>  	default:
>  		return -EINVAL;
>  	}

Without patch description: See Last Question in

Documentation/power/power_supply_class.txt

-- Sebastian