lwmi_attr_id
lwmi_attr_id(LWMI_DEVICE_ID_FAN, LWMI_FEATURE_ID_FAN_TEST, \
lwmi_attr_id(LWMI_DEVICE_ID_FAN, LWMI_FEATURE_ID_FAN_RPM, \
lwmi_attr_id(LWMI_DEVICE_ID_PSU, feat, \
return lwmi_attr_id(attr->device_id, attr->feature_id, mode, attr->type_id);