EMC2305_REG_FAN_DRIVE
ret = i2c_smbus_write_byte_data(client, EMC2305_REG_FAN_DRIVE(cdev_idx), val);
ret = i2c_smbus_write_byte_data(client, EMC2305_REG_FAN_DRIVE(i), val);
return i2c_smbus_read_byte_data(client, EMC2305_REG_FAN_DRIVE(channel));
ret = i2c_smbus_write_byte_data(client, EMC2305_REG_FAN_DRIVE(channel), val);