Today I tried to run cardserver on my favourite piece of hardware – ALIX 2d2. I used serial Phoenix reader and up-to-date OScam. I struggled a lot of time trying to force reader to communicate via serial interface, because using USB-Serial converted it worked like a charm.
Finally, after reading ALIX documentation I found this:
Due to limitations in the AMD CS5536 companion chip, the serial port only supports RXD / TXD, not the handshake signals.
So the only solution is to use native USB reader or connect serial reader through USB-Serial converter.