[34-longterm 031/209] olpc_battery: Fix endian neutral breakage for s16 values

From: Paul Gortmaker
Date: Thu Apr 14 2011 - 13:46:06 EST


From: Richard A. Smith <richard@xxxxxxxxxx>

=====================================================================
| This is a commit scheduled for the next v2.6.34 longterm release. |
| If you see a problem with using this for longterm, please comment.|
=====================================================================

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: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
drivers/power/olpc_battery.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
index 8fefe5a..4b38eaa 100644
--- 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);
--
1.7.4.4

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