Freeing UART on Raspberry pi

[chriskyp]

hello to all of you,
this is my first post on this site, which so far i have learned much!!
I have a small-big problem though.
i am using one of the guides to start using my NFC reader on my Pi from this link:
https://learn.adafruit.com/adafruit-nfc ... -on-the-pi
when i do the alterations on cmdline.txt and inittab i restart my Pi only to see that
vfs cannot open root device (null) or unknown-block(0 0) and freezes can make it boot or anything,
i have been googling around and there is no clear solution on that problem.
at the end i formatted my SD card and install Raspbian again. I am currently doing my Final Year Project
which is due in a week or so and i am stuck here, lost almost all my data and for nothing.
Could you please help me with this? why is this happening??

[chriskyp]

is there a solution using i2c??

[adafruit_support_mike]

Post the contents of your /boot/cmdline.txt file and we'll see what we can find.

[chriskyp]

first of all thank you for your reply...
i finally did it! but now all i get is:
pn53x_check_communication: Timeout
nfc-poll: ERROR: Unable to open NFC device.