i2c: Fix probing of FSC hardware monitoring chips

[karo-tx-linux.git] / drivers / i2c / i2c-core.c

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index b9306b1a6baa0e0f30d5777e3eb5782020aa0560..5105126225c3c05b694c85d751c60114db4df922 100644 (file)
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1264,12 +1264,23 @@ static int i2c_detect_address(struct i2c_client *temp_client,
                return 0;
 
        /* Make sure there is something at this address */
-       if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) < 0)
-               return 0;
+       if (addr == 0x73 && (adapter->class & I2C_CLASS_HWMON)) {
+               /* Special probe for FSC hwmon chips */
+               union i2c_smbus_data dummy;
 
-       /* Prevent 24RF08 corruption */
-       if ((addr & ~0x0f) == 0x50)
-               i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL);
+               if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_READ, 0,
+                                  I2C_SMBUS_BYTE_DATA, &dummy) < 0)
+                       return 0;
+       } else {
+               if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
+                                  I2C_SMBUS_QUICK, NULL) < 0)
+                       return 0;
+
+               /* Prevent 24RF08 corruption */
+               if ((addr & ~0x0f) == 0x50)
+                       i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
+                                      I2C_SMBUS_QUICK, NULL);
+       }
 
        /* Finally call the custom detection function */
        memset(&info, 0, sizeof(struct i2c_board_info));