[PATCH 4.9 106/206] hwmon: (amc6821) sign extension temperature

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

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

From: Jared Bents <jared.bents@xxxxxxxxxxxxxxxxxxx>

commit 4538bfbf2d9f1fc48c07ac0cc0ee58716fe7fe96 upstream.

Converts the unsigned temperature values from the i2c read
to be sign extended as defined in the datasheet so that
negative temperatures are properly read.

Fixes: 28e6274d8fa67 ("hwmon: (amc6821) Avoid forward declaration")
Signed-off-by: Jared Bents <jared.bents@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Matt Weber <matthew.weber@xxxxxxxxxxxxxxxxxxx>
[groeck: Dropped unnecessary continuation line]
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/hwmon/amc6821.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -188,8 +188,8 @@ static struct amc6821_data *amc6821_upda
 			!data->valid) {
 
 		for (i = 0; i < TEMP_IDX_LEN; i++)
-			data->temp[i] = i2c_smbus_read_byte_data(client,
-				temp_reg[i]);
+			data->temp[i] = (int8_t)i2c_smbus_read_byte_data(
+				client, temp_reg[i]);
 
 		data->stat1 = i2c_smbus_read_byte_data(client,
 			AMC6821_REG_STAT1);