power: supply: bq25890: Document POWER_SUPPLY_PROP_CURRENT_NOW

Document that POWER_SUPPLY_PROP_CURRENT_NOW really does refer to ADC-sampled
immediate battery charge current I_BAT , since the meaning is not clear with
all the currents which might be measured by charger chips.
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/bq25890_charger.c

@@ -588,7 +588,14 @@ static int bq25890_power_supply_get_property(struct power_supply *psy,
 		val->intval = 2304000 + ret * 20000;
 		break;
 
-	case POWER_SUPPLY_PROP_CURRENT_NOW:
+	case POWER_SUPPLY_PROP_CURRENT_NOW:	/* I_BAT now */
+		/*
+		 * This is ADC-sampled immediate charge current supplied
+		 * from charger to battery. The property name is confusing,
+		 * for clarification refer to:
+		 * Documentation/ABI/testing/sysfs-class-power
+		 * /sys/class/power_supply/<supply_name>/current_now
+		 */
 		ret = bq25890_field_read(bq, F_ICHGR); /* read measured value */
 		if (ret < 0)
 			return ret;