diff options
Diffstat (limited to 'drivers/hwmon/lm73.c')
| -rw-r--r-- | drivers/hwmon/lm73.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/drivers/hwmon/lm73.c b/drivers/hwmon/lm73.c index 29b9030d42c..24be17608fb 100644 --- a/drivers/hwmon/lm73.c +++ b/drivers/hwmon/lm73.c @@ -150,17 +150,31 @@ static int lm73_detect(struct i2c_client *new_client, struct i2c_board_info *info) { struct i2c_adapter *adapter = new_client->adapter; - u16 id; - u8 ctrl; + int id, ctrl, conf; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) return -ENODEV; + /* + * Do as much detection as possible with byte reads first, as word + * reads can confuse other devices. + */ + ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL); + if (ctrl < 0 || (ctrl & 0x10)) + return -ENODEV; + + conf = i2c_smbus_read_byte_data(new_client, LM73_REG_CONF); + if (conf < 0 || (conf & 0x0c)) + return -ENODEV; + + id = i2c_smbus_read_byte_data(new_client, LM73_REG_ID); + if (id < 0 || id != (LM73_ID & 0xff)) + return -ENODEV; + /* Check device ID */ id = i2c_smbus_read_word_data(new_client, LM73_REG_ID); - ctrl = i2c_smbus_read_byte_data(new_client, LM73_REG_CTRL); - if ((id != LM73_ID) || (ctrl & 0x10)) + if (id < 0 || id != LM73_ID) return -ENODEV; strlcpy(info->type, "lm73", I2C_NAME_SIZE); |