hwmon: (lm90) Support the extra resolution bits of MAX6657

The Maxim MAX6657, MAX6658 and MAX6659 have extra resolution bits for
the local temperature measurement. Let the lm90 driver read them and
export them to user-space.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Martyn Welch <martyn.welch@gefanuc.com>

1 files changed, 33 insertions, 21 deletions

diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index 73a1c622fb7a..16b99e0bdff0 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -149,6 +149,10 @@ I2C_CLIENT_INSMOD_7(lm90, adm1032, lm99, lm86, max6657, adt7461, max6680);
 #define LM90_REG_R_TCRIT_HYST           0x21
 #define LM90_REG_W_TCRIT_HYST           0x21
 
+/* MAX6657-specific registers */
+
+#define MAX6657_REG_R_LOCAL_TEMPL       0x11
+
 /*
  * Conversions and various macros
  * For local temperatures and limits, critical limits and the hysteresis
@@ -239,15 +243,15 @@ struct lm90_data {
         int kind;
 
         /* registers values */
-        s8 temp8[5];    /* 0: local input
-                           1: local low limit
-                           2: local high limit
-                           3: local critical limit
-                           4: remote critical limit */
-        s16 temp11[4];  /* 0: remote input
+        s8 temp8[4];    /* 0: local low limit
+                           1: local high limit
+                           2: local critical limit
+                           3: remote critical limit */
+        s16 temp11[5];  /* 0: remote input
                            1: remote low limit
                            2: remote high limit
-                           3: remote offset (except max6657) */
+                           3: remote offset (except max6657)
+                           4: local input */
         u8 temp_hyst;
         u8 alarms; /* bitvector */
 };
@@ -285,7 +289,7 @@ static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr,
                 data->temp8[nr] = TEMP1_TO_REG_ADT7461(val);
         else
                 data->temp8[nr] = TEMP1_TO_REG(val);
-        i2c_smbus_write_byte_data(client, reg[nr - 1], data->temp8[nr]);
+        i2c_smbus_write_byte_data(client, reg[nr], data->temp8[nr]);
         mutex_unlock(&data->update_lock);
         return count;
 }
@@ -347,7 +351,7 @@ static ssize_t set_temphyst(struct device *dev, struct device_attribute *dummy,
         long hyst;
 
         mutex_lock(&data->update_lock);
-        hyst = TEMP1_FROM_REG(data->temp8[3]) - val;
+        hyst = TEMP1_FROM_REG(data->temp8[2]) - val;
         i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
                                   HYST_TO_REG(hyst));
         mutex_unlock(&data->update_lock);
@@ -371,23 +375,23 @@ static ssize_t show_alarm(struct device *dev, struct device_attribute
         return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 }
 
-static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp8, NULL, 0);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp11, NULL, 4);
 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp11, NULL, 0);
 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp8,
-        set_temp8, 1);
+        set_temp8, 0);
 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp11,
         set_temp11, 1);
 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp8,
-        set_temp8, 2);
+        set_temp8, 1);
 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp11,
         set_temp11, 2);
 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp8,
-        set_temp8, 3);
+        set_temp8, 2);
 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp8,
-        set_temp8, 4);
+        set_temp8, 3);
 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temphyst,
-        set_temphyst, 3);
-static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temphyst, NULL, 4);
+        set_temphyst, 2);
+static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temphyst, NULL, 3);
 static SENSOR_DEVICE_ATTR(temp2_offset, S_IWUSR | S_IRUGO, show_temp11,
         set_temp11, 3);
 
@@ -779,13 +783,21 @@ static struct lm90_data *lm90_update_device(struct device *dev)
                 u8 h, l;
 
                 dev_dbg(&client->dev, "Updating lm90 data.\n");
-                lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP, &data->temp8[0]);
-                lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[1]);
-                lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH, &data->temp8[2]);
-                lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT, &data->temp8[3]);
-                lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT, &data->temp8[4]);
+                lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[0]);
+                lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH, &data->temp8[1]);
+                lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT, &data->temp8[2]);
+                lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT, &data->temp8[3]);
                 lm90_read_reg(client, LM90_REG_R_TCRIT_HYST, &data->temp_hyst);
 
+                if (data->kind == max6657) {
+                        lm90_read16(client, LM90_REG_R_LOCAL_TEMP,
+                                    MAX6657_REG_R_LOCAL_TEMPL,
+                                    &data->temp11[4]);
+                } else {
+                        if (lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP,
+                                          &h) == 0)
+                                data->temp11[4] = h << 8;
+                }
                 lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
                             LM90_REG_R_REMOTE_TEMPL, &data->temp11[0]);