hwmon: (lm63) Consider LM64 temperature offset

LM64 has 16 degrees Celsius temperature offset on all
remote sensor registers.
This was not considered When LM64 support was added to lm63.c.

Signed-off-by: Dirk Eibach <eibach@gdsys.de>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: stable@kernel.org

1 files changed, 47 insertions, 12 deletions

diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
index 776aeb3019d2..508cb291f71b 100644
--- a/drivers/hwmon/lm63.c
+++ b/drivers/hwmon/lm63.c
@@ -98,6 +98,9 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };
  * value, it uses signed 8-bit values with LSB = 1 degree Celsius.
  * For remote temperature, low and high limits, it uses signed 11-bit values
  * with LSB = 0.125 degree Celsius, left-justified in 16-bit registers.
+ * For LM64 the actual remote diode temperature is 16 degree Celsius higher
+ * than the register reading. Remote temperature setpoints have to be
+ * adapted accordingly.
  */
 
 #define FAN_FROM_REG(reg)       ((reg) == 0xFFFC || (reg) == 0 ? 0 : \
@@ -165,6 +168,8 @@ struct lm63_data {
         struct mutex update_lock;
         char valid; /* zero until following fields are valid */
         unsigned long last_updated; /* in jiffies */
+        int kind;
+        int temp2_offset;
 
         /* registers values */
         u8 config, config_fan;
@@ -247,16 +252,34 @@ static ssize_t show_pwm1_enable(struct device *dev, struct device_attribute *dum
         return sprintf(buf, "%d\n", data->config_fan & 0x20 ? 1 : 2);
 }
 
-static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
-                          char *buf)
+/*
+ * There are 8bit registers for both local(temp1) and remote(temp2) sensor.
+ * For remote sensor registers temp2_offset has to be considered,
+ * for local sensor it must not.
+ * So we need separate 8bit accessors for local and remote sensor.
+ */
+static ssize_t show_local_temp8(struct device *dev,
+                                struct device_attribute *devattr,
+                                char *buf)
 {
         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
         struct lm63_data *data = lm63_update_device(dev);
         return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[attr->index]));
 }
 
-static ssize_t set_temp8(struct device *dev, struct device_attribute *dummy,
-                         const char *buf, size_t count)
+static ssize_t show_remote_temp8(struct device *dev,
+                                 struct device_attribute *devattr,
+                                 char *buf)
+{
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+        struct lm63_data *data = lm63_update_device(dev);
+        return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[attr->index])
+                       + data->temp2_offset);
+}
+
+static ssize_t set_local_temp8(struct device *dev,
+                               struct device_attribute *dummy,
+                               const char *buf, size_t count)
 {
         struct i2c_client *client = to_i2c_client(dev);
         struct lm63_data *data = i2c_get_clientdata(client);
@@ -274,7 +297,8 @@ static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
 {
         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
         struct lm63_data *data = lm63_update_device(dev);
-        return sprintf(buf, "%d\n", TEMP11_FROM_REG(data->temp11[attr->index]));
+        return sprintf(buf, "%d\n", TEMP11_FROM_REG(data->temp11[attr->index])
+                       + data->temp2_offset);
 }
 
 static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
@@ -294,7 +318,7 @@ static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
         int nr = attr->index;
 
         mutex_lock(&data->update_lock);
-        data->temp11[nr] = TEMP11_TO_REG(val);
+        data->temp11[nr] = TEMP11_TO_REG(val - data->temp2_offset);
         i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2],
                                   data->temp11[nr] >> 8);
         i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2 + 1],
@@ -310,6 +334,7 @@ static ssize_t show_temp2_crit_hyst(struct device *dev, struct device_attribute
 {
         struct lm63_data *data = lm63_update_device(dev);
         return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[2])
+                       + data->temp2_offset
                        - TEMP8_FROM_REG(data->temp2_crit_hyst));
 }
 
@@ -324,7 +349,7 @@ static ssize_t set_temp2_crit_hyst(struct device *dev, struct device_attribute *
         long hyst;
 
         mutex_lock(&data->update_lock);
-        hyst = TEMP8_FROM_REG(data->temp8[2]) - val;
+        hyst = TEMP8_FROM_REG(data->temp8[2]) + data->temp2_offset - val;
         i2c_smbus_write_byte_data(client, LM63_REG_REMOTE_TCRIT_HYST,
                                   HYST_TO_REG(hyst));
         mutex_unlock(&data->update_lock);
@@ -355,16 +380,21 @@ static SENSOR_DEVICE_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan,
 static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm1, set_pwm1);
 static DEVICE_ATTR(pwm1_enable, S_IRUGO, show_pwm1_enable, NULL);
 
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp8, NULL, 0);
-static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp8,
-        set_temp8, 1);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_local_temp8, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_local_temp8,
+        set_local_temp8, 1);
 
 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp11, NULL, 0);
 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp11,
         set_temp11, 1);
 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp11,
         set_temp11, 2);
-static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp8, NULL, 2);
+/*
+ * On LM63, temp2_crit can be set only once, which should be job
+ * of the bootloader.
+ */
+static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_remote_temp8,
+        NULL, 2);
 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp2_crit_hyst,
         set_temp2_crit_hyst);
 
@@ -479,7 +509,12 @@ static int lm63_probe(struct i2c_client *new_client,
         data->valid = 0;
         mutex_init(&data->update_lock);
 
-        /* Initialize the LM63 chip */
+        /* Set the device type */
+        data->kind = id->driver_data;
+        if (data->kind == lm64)
+                data->temp2_offset = 16000;
+
+        /* Initialize chip */
         lm63_init_client(new_client);
 
         /* Register sysfs hooks */