Hi,
try to put AIX CD volume 1 to CD-ROM drive and run "smitty cfgmgr" command. In smitty screen select to input device box "/dev/cd0 (SCSI Multimedia CD-ROM Drive)" and press enter.
This should install missing device driver. If this doesn't work driver is probably missing from your installation media. In that case you might want to seek correct driver from
IBM support website.
--Tommy