Problem with USB serial in linux emulation

Morgan Wesström freebsd-questions at
Thu Jan 14 18:40:27 UTC 2010

Dear list.

I have an USB smartcard reader that emulates a serial port. It uses the
uftdi.ko kernel module and creates the following device nodes when
plugged in. System is FreeBSD 7.2-RELEASE-p3 amd64.

crw-rw----  1 uucp  dialer    0, 110 Jan 14 19:27 /dev/cuaU0
crw-rw----  1 uucp  dialer    0, 111 Jan  7 14:01 /dev/cuaU0.init
crw-rw----  1 uucp  dialer    0, 112 Jan  7 14:01 /dev/cuaU0.lock
crw-------  1 root  wheel     0, 107 Jan 14 19:25 /dev/ttyU0
crw-------  1 root  wheel     0, 108 Jan  7 14:01 /dev/ttyU0.init
crw-------  1 root  wheel     0, 109 Jan  7 14:01 /dev/ttyU0.lock

dmesg output:

ucom0: <FTDI USB <-> Serial, class 0/0, rev 1.10/4.00, addr 2> on uhub5

I'm trying to access it with a linux program and the program initializes
and manages to read at least some basic info from the card but any
further communication with the card results in the following message
regardless of what device node I use:

linux_sys_futex: unknown op 265

Same software and reader works on a pure linux machine.

Does anyone have any hints on what I can do to try to track this problem
down? Some clarification on what the difference is between cuaU0 and
ttyU0 would be appreciated too and which of them I should use primarily.


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