My ACR122U207 crashed while breaking Mfoc

  [root@openpcd bin]# ./nfc-list 
   ./nfc-list uses libnfc 1.5.0 (r1121)
   Connected to NFC device: ACS ACR122U PICC Interface 00 00 / ACR122U207 - PN532 v1.6 (0x07)
   1 ISO14443A passive target(s) found:
    ATQA (SENS_RES): 00  04  
       UID (NFCID1): XX XX XX XX
      SAK (SEL_RES): 08  

[root@openpcd bin]# ./mfoc -P 500 -O myCrad_dump
    ATQA (SENS_RES): 00  04  
* UID size: single
* bit frame anticollision supported
       UID (NFCID1): XX XX XX XX
      SAK (SEL_RES): 08  
* Not compliant with ISO/IEC 14443-4
* Not compliant with ISO/IEC 18092
Fingerprinting based on ATQA & SAK values:
* Mifare Classic 1K
* Mifare Plus (4-byte UID) 2K SL1
* SmartMX with Mifare 1K emulation
[Key: ffffffffffff] -> [................]
[Key: a0a1a2a3a4a5] -> [x...............]
[Key: d3f7d3f7d3f7] -> [x...............]
[Key: 000000000000] -> [x.......nfc_initiator_init: Input/output error


[root@openpcd bin]# ./mfoc -h
Usage: mfoc [-h] [-k key]... [-P probnum] [-T tolerance] [-O output]

  h     print this help and exit
  k     try the specified key in addition to the default keys
  P     number of probes per sector, instead of default of 20
  T     nonce tolerance half-range, instead of default of 20
        (i.e., 40 for the total range, in both directions)
  O     file in which the card contents will be written (REQUIRED)

Example: mfoc -O mycard.mfd
Example: mfoc -k ffffeeeedddd -O mycard.mfd
Example: mfoc -P 50 -T 30 -O mycard.mfd

This is mfoc version 0.10.2.
For more information, run: 'man mfoc'.
[root@openpcd bin]# 


[root@openpcd drivers]# uname -a
Linux openpcd.local 2.6.38.6-26.rc1.fc15.x86_64 #1 SMP Mon May 9 20:45:15 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux
[root@openpcd drivers]# cat /etc/issue
Fedora release 15 (Lovelock)
Kernel \r on an \m (\l)