1 files changed, 15 insertions, 17 deletions

diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 1002befd87d5..5be09c048c5f 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -539,14 +539,14 @@ static ssize_t set_sensor(struct device *dev, struct device_attribute *attr,
 
         struct it87_data *data = dev_get_drvdata(dev);
         long val;
+        u8 reg;
 
         if (strict_strtol(buf, 10, &val) < 0)
                 return -EINVAL;
 
-        mutex_lock(&data->update_lock);
-
-        data->sensor &= ~(1 << nr);
-        data->sensor &= ~(8 << nr);
+        reg = it87_read_value(data, IT87_REG_TEMP_ENABLE);
+        reg &= ~(1 << nr);
+        reg &= ~(8 << nr);
         if (val == 2) { /* backwards compatibility */
                 dev_warn(dev, "Sensor type 2 is deprecated, please use 4 "
                          "instead\n");
@@ -554,14 +554,16 @@ static ssize_t set_sensor(struct device *dev, struct device_attribute *attr,
         }
         /* 3 = thermal diode; 4 = thermistor; 0 = disabled */
         if (val == 3)
-                data->sensor |= 1 << nr;
+                reg |= 1 << nr;
         else if (val == 4)
-                data->sensor |= 8 << nr;
-        else if (val != 0) {
-                mutex_unlock(&data->update_lock);
+                reg |= 8 << nr;
+        else if (val != 0)
                 return -EINVAL;
-        }
+
+        mutex_lock(&data->update_lock);
+        data->sensor = reg;
         it87_write_value(data, IT87_REG_TEMP_ENABLE, data->sensor);
+        data->valid = 0;        /* Force cache refresh */
         mutex_unlock(&data->update_lock);
         return count;
 }
@@ -1841,14 +1843,10 @@ static void __devinit it87_init_device(struct platform_device *pdev)
                         it87_write_value(data, IT87_REG_TEMP_HIGH(i), 127);
         }
 
-        /* Check if temperature channels are reset manually or by some reason */
-        tmp = it87_read_value(data, IT87_REG_TEMP_ENABLE);
-        if ((tmp & 0x3f) == 0) {
-                /* Temp1,Temp3=thermistor; Temp2=thermal diode */
-                tmp = (tmp & 0xc0) | 0x2a;
-                it87_write_value(data, IT87_REG_TEMP_ENABLE, tmp);
-        }
-        data->sensor = tmp;
+        /* Temperature channels are not forcibly enabled, as they can be
+         * set to two different sensor types and we can't guess which one
+         * is correct for a given system. These channels can be enabled at
+         * run-time through the temp{1-3}_type sysfs accessors if needed. */
 
         /* Check if voltage monitors are reset manually or by some reason */
         tmp = it87_read_value(data, IT87_REG_VIN_ENABLE);