it87: No sysfs files for disabled fans

it87: No sysfs files for disabled fans

Only create the fan attributes for enabled fan tachometers. Some
motherboards have a nice BIOS which only enables the fan inputs which
are wired to a fan header on the board. This makes the configuration
easier for the user.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 51 insertions, 32 deletions

diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index e7f14e61d6f2..0317e441ca51 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -222,6 +222,7 @@ struct it87_data {
         u8 in[9];               /* Register value */
         u8 in_max[9];           /* Register value */
         u8 in_min[9];           /* Register value */
+        u8 has_fan;             /* Bitfield, fans enabled */
         u16 fan[3];             /* Register values, possibly combined */
         u16 fan_min[3];         /* Register values, possibly combined */
         u8 temp[3];             /* Register value */
@@ -967,38 +968,51 @@ static int it87_detect(struct i2c_adapter *adapter, int address, int kind)
         device_create_file(&new_client->dev, &sensor_dev_attr_temp2_type.dev_attr);
         device_create_file(&new_client->dev, &sensor_dev_attr_temp3_type.dev_attr);
 
+        /* Do not create fan files for disabled fans */
         if (data->type == it8716) { /* 16-bit tachometers */
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan1_input16.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan2_input16.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan3_input16.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan1_min16.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan2_min16.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan3_min16.dev_attr);
+                if (data->has_fan & (1 << 0)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan1_input16.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan1_min16.dev_attr);
+                }
+                if (data->has_fan & (1 << 1)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan2_input16.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan2_min16.dev_attr);
+                }
+                if (data->has_fan & (1 << 2)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan3_input16.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan3_min16.dev_attr);
+                }
         } else {
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan1_input.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan2_input.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan3_input.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan1_min.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan2_min.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan3_min.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan1_div.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan2_div.dev_attr);
-                device_create_file(&new_client->dev,
-                                   &sensor_dev_attr_fan3_div.dev_attr);
+                if (data->has_fan & (1 << 0)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan1_input.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan1_min.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan1_div.dev_attr);
+                }
+                if (data->has_fan & (1 << 1)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan2_input.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan2_min.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan2_div.dev_attr);
+                }
+                if (data->has_fan & (1 << 2)) {
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan3_input.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan3_min.dev_attr);
+                        device_create_file(&new_client->dev,
+                                &sensor_dev_attr_fan3_div.dev_attr);
+                }
         }
 
         device_create_file(&new_client->dev, &dev_attr_alarms);
@@ -1175,11 +1189,12 @@ static void it87_init_client(struct i2c_client *client, struct it87_data *data)
                 data->fan_main_ctrl |= 0x70;
                 it87_write_value(client, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
         }
+        data->has_fan = (data->fan_main_ctrl >> 4) & 0x07;
 
         /* Set tachometers to 16-bit mode if needed */
         if (data->type == it8716) {
                 tmp = it87_read_value(client, IT87_REG_FAN_16BIT);
-                if ((tmp & 0x07) != 0x07) {
+                if (~tmp & 0x07 & data->has_fan) {
                         dev_dbg(&client->dev,
                                 "Setting fan1-3 to 16-bit mode\n");
                         it87_write_value(client, IT87_REG_FAN_16BIT,
@@ -1244,6 +1259,10 @@ static struct it87_data *it87_update_device(struct device *dev)
                 data->in_max[8] = 255;
 
                 for (i = 0; i < 3; i++) {
+                        /* Skip disabled fans */
+                        if (!(data->has_fan & (1 << i)))
+                                continue;
+
                         data->fan_min[i] =
                             it87_read_value(client, IT87_REG_FAN_MIN(i));
                         data->fan[i] = it87_read_value(client,
@@ -1266,7 +1285,7 @@ static struct it87_data *it87_update_device(struct device *dev)
                 }
 
                 /* Newer chips don't have clock dividers */
-                if (data->type != it8716) {
+                if ((data->has_fan & 0x07) && data->type != it8716) {
                         i = it87_read_value(client, IT87_REG_FAN_DIV);
                         data->fan_div[0] = i & 0x07;
                         data->fan_div[1] = (i >> 3) & 0x07;