olpc_battery: Fix endian neutral breakage for s16 values

When the driver was updated to be endian neutral (8e9c7716c)
the signed part of the s16 values was lost.  This is because be16_to_cpu()
returns an unsigned value.  This patch casts the values back to a s16
number prior to the the implicit cast up to an int.

Signed-off-by: Richard A. Smith <richard@laptop.org>
Signed-off-by: Daniel Drake <dsd@laptop.org>
Cc: <stable@kernel.org>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
index aafc1c5..5bc1dcf 100644 (file)
--- a/drivers/power/olpc_battery.c
+++ b/drivers/power/olpc_battery.c
@@ -271,14 +271,14 @@ static int olpc_bat_get_property(struct power_supply *psy,
                if (ret)
                        return ret;
 
-               val->intval = (int)be16_to_cpu(ec_word) * 9760L / 32;
+               val->intval = (s16)be16_to_cpu(ec_word) * 9760L / 32;
                break;
        case POWER_SUPPLY_PROP_CURRENT_AVG:
                ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
                if (ret)
                        return ret;
 
-               val->intval = (int)be16_to_cpu(ec_word) * 15625L / 120;
+               val->intval = (s16)be16_to_cpu(ec_word) * 15625L / 120;
                break;
        case POWER_SUPPLY_PROP_CAPACITY:
                ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
@@ -299,7 +299,7 @@ static int olpc_bat_get_property(struct power_supply *psy,
                if (ret)
                        return ret;
 
-               val->intval = (int)be16_to_cpu(ec_word) * 100 / 256;
+               val->intval = (s16)be16_to_cpu(ec_word) * 100 / 256;
                break;
        case POWER_SUPPLY_PROP_TEMP_AMBIENT:
                ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
@@ -313,7 +313,7 @@ static int olpc_bat_get_property(struct power_supply *psy,
                if (ret)
                        return ret;
 
-               val->intval = (int)be16_to_cpu(ec_word) * 6250 / 15;
+               val->intval = (s16)be16_to_cpu(ec_word) * 6250 / 15;
                break;
        case POWER_SUPPLY_PROP_SERIAL_NUMBER:
                ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8);