I know, I added libsixaxis already to the code, only thing left if boot with 58Cfg USB Loader dosen't use libsixaxis. Cfg boots in cios 222 or 249 at the moment it doesn't have the capability to boot in ios58 natively so at the moment it's not possible to use a PS3 DualShock 3 inside Cfg. I'm sorry.
As supposed, Cfg uses usbstorage_starlet to access USB. I have a Cfg version that boots with ios 58 but still doesn't find anything, no USB and no SD...