comms_msg_header
data_ptr = (u8 *)fw_desc + sizeof(struct comms_msg_header);
temp_fw_desc = vzalloc(sizeof(struct comms_msg_header) + fw_data_size);
memcpy_fromio(temp_fw_desc, src, sizeof(struct comms_msg_header) + fw_data_size);
msg->header.size = cpu_to_le16(sizeof(struct comms_msg_header));
struct comms_msg_header header;