power: supply: rk817: Change rk817_chg_cur_to_reg to int

Change return value of rk817_chg_cur_to_reg from u8 to int. If the
function fails to find a suitable value it returns a -EINVAL, but
defined as a u8 it would not return correctly. Additionally, change
defined variable that stores return value from u8 to int.

Fixes: 11cb8da0 ("power: supply: Add charger driver for Rockchip RK817")
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/rk817_charger.c

@@ -121,7 +121,7 @@ struct rk817_charger {
 #define ADC_TO_CHARGE_UAH(adc_value, res_div)	\
 	(adc_value / 3600 * 172 / res_div)
 
-static u8 rk817_chg_cur_to_reg(u32 chg_cur_ma)
+static int rk817_chg_cur_to_reg(u32 chg_cur_ma)
 {
 	if (chg_cur_ma >= 3500)
 		return CHG_3_5A;
@@ -864,8 +864,8 @@ static int rk817_battery_init(struct rk817_charger *charger,
 {
 	struct rk808 *rk808 = charger->rk808;
 	u32 tmp, max_chg_vol_mv, max_chg_cur_ma;
-	u8 max_chg_vol_reg, chg_term_i_reg, max_chg_cur_reg;
-	int ret, chg_term_ma;
+	u8 max_chg_vol_reg, chg_term_i_reg;
+	int ret, chg_term_ma, max_chg_cur_reg;
 	u8 bulk_reg[2];
 
 	/* Get initial plug state */