max17042_battery: Support CHARGE_COUNTER power supply attribute

This patch adds the support for CHARGE_COUNTER power supply attribute
to max17042/47 driver.

Note:QH(Charge Counter) register is not documented in max17042 the Spec.
Signed-off-by: NRamakrishna Pallala <ramakrishna.pallala@intel.com>
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>

drivers/power/max17042_battery.c

@@ -113,6 +113,7 @@ static enum power_supply_property max17042_battery_props[] = {
 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
 	POWER_SUPPLY_PROP_CAPACITY,
 	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_COUNTER,
 	POWER_SUPPLY_PROP_TEMP,
 	POWER_SUPPLY_PROP_CURRENT_NOW,
 	POWER_SUPPLY_PROP_CURRENT_AVG,
@@ -199,6 +200,13 @@ static int max17042_get_property(struct power_supply *psy,
 		if (ret < 0)
 			return ret;
 
+		val->intval = ret * 1000 / 2;
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
+		ret = max17042_read_reg(chip->client, MAX17042_QH);
+		if (ret < 0)
+			return ret;
+
 		val->intval = ret * 1000 / 2;
 		break;
 	case POWER_SUPPLY_PROP_TEMP: