[102/289] olpc_battery: Fix endian neutral breakage for s16 values

From: Greg KH
Date: Tue Dec 07 2010 - 20:41:42 EST


2.6.36-stable review patch. If anyone has any objections, please let us know.

------------------

From: Richard A. Smith <richard@xxxxxxxxxx>

commit 7cfbb29466633e6ecdc14f76a693c8478c2b22af upstream.

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@xxxxxxxxxx>
Signed-off-by: Daniel Drake <dsd@xxxxxxxxxx>
Signed-off-by: Anton Vorontsov <cbouatmailru@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/power/olpc_battery.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/power/olpc_battery.c
+++ b/drivers/power/olpc_battery.c
@@ -271,14 +271,14 @@ static int olpc_bat_get_property(struct
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
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
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);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/