hwmon: (lm85) Don't bind to Winbond/Nuvoton WPCD377I

[cascardo/linux.git] / drivers / hwmon / lm85.c

diff --git a/drivers/hwmon/lm85.c b/drivers/hwmon/lm85.c
index b251d86..6c53d98 100644 (file)
--- a/drivers/hwmon/lm85.c
+++ b/drivers/hwmon/lm85.c
@@ -75,6 +75,8 @@ I2C_CLIENT_INSMOD_7(lm85b, lm85c, adm1027, adt7463, adt7468, emc6d100,
 #define        LM85_VERSTEP_GENERIC2           0x70
 #define        LM85_VERSTEP_LM85C              0x60
 #define        LM85_VERSTEP_LM85B              0x62
+#define        LM85_VERSTEP_LM96000_1          0x68
+#define        LM85_VERSTEP_LM96000_2          0x69
 #define        LM85_VERSTEP_ADM1027            0x60
 #define        LM85_VERSTEP_ADT7463            0x62
 #define        LM85_VERSTEP_ADT7463C           0x6A
@@ -1133,6 +1135,26 @@ static void lm85_init_client(struct i2c_client *client)
                dev_warn(&client->dev, "Device is not ready\n");
 }
 
+static int lm85_is_fake(struct i2c_client *client)
+{
+       /*
+        * Differenciate between real LM96000 and Winbond WPCD377I. The latter
+        * emulate the former except that it has no hardware monitoring function
+        * so the readings are always 0.
+        */
+       int i;
+       u8 in_temp, fan;
+
+       for (i = 0; i < 8; i++) {
+               in_temp = i2c_smbus_read_byte_data(client, 0x20 + i);
+               fan = i2c_smbus_read_byte_data(client, 0x28 + i);
+               if (in_temp != 0x00 || fan != 0xff)
+                       return 0;
+       }
+
+       return 1;
+}
+
 /* Return 0 if detection is successful, -ENODEV otherwise */
 static int lm85_detect(struct i2c_client *client, int kind,
                       struct i2c_board_info *info)
@@ -1173,6 +1195,16 @@ static int lm85_detect(struct i2c_client *client, int kind,
                        case LM85_VERSTEP_LM85B:
                                kind = lm85b;
                                break;
+                       case LM85_VERSTEP_LM96000_1:
+                       case LM85_VERSTEP_LM96000_2:
+                               /* Check for Winbond WPCD377I */
+                               if (lm85_is_fake(client)) {
+                                       dev_dbg(&adapter->dev,
+                                               "Found Winbond WPCD377I, "
+                                               "ignoring\n");
+                                       return -ENODEV;
+                               }
+                               break;
                        }
                } else if (company == LM85_COMPANY_ANALOG_DEV) {
                        switch (verstep) {