hwmon: (adm1026) Fix setting fan_div

Prevent setting fan_div from stomping on other fans that share the
same I2C register.

Signed-off-by: Gabriele Gorla <gorlik@penguintown.net>
Cc: stable@kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/adm1026.c b/drivers/hwmon/adm1026.c
index 4bf969c..6f257ce 100644
--- a/drivers/hwmon/adm1026.c
+++ b/drivers/hwmon/adm1026.c
@@ -916,7 +916,7 @@
 	int nr = sensor_attr->index;
 	struct i2c_client *client = to_i2c_client(dev);
 	struct adm1026_data *data = i2c_get_clientdata(client);
-	int val, orig_div, new_div, shift;
+	int val, orig_div, new_div;
 
 	val = simple_strtol(buf, NULL, 10);
 	new_div = DIV_TO_REG(val);
@@ -928,15 +928,17 @@
 	data->fan_div[nr] = DIV_FROM_REG(new_div);
 
 	if (nr < 4) { /* 0 <= nr < 4 */
-		shift = 2 * nr;
 		adm1026_write_value(client, ADM1026_REG_FAN_DIV_0_3,
-			((DIV_TO_REG(orig_div) & (~(0x03 << shift))) |
-			(new_div << shift)));
+				    (DIV_TO_REG(data->fan_div[0]) << 0) |
+				    (DIV_TO_REG(data->fan_div[1]) << 2) |
+				    (DIV_TO_REG(data->fan_div[2]) << 4) |
+				    (DIV_TO_REG(data->fan_div[3]) << 6));
 	} else { /* 3 < nr < 8 */
-		shift = 2 * (nr - 4);
 		adm1026_write_value(client, ADM1026_REG_FAN_DIV_4_7,
-			((DIV_TO_REG(orig_div) & (~(0x03 << (2 * shift)))) |
-			(new_div << shift)));
+				    (DIV_TO_REG(data->fan_div[4]) << 0) |
+				    (DIV_TO_REG(data->fan_div[5]) << 2) |
+				    (DIV_TO_REG(data->fan_div[6]) << 4) |
+				    (DIV_TO_REG(data->fan_div[7]) << 6));
 	}
 
 	if (data->fan_div[nr] != orig_div) {