Topic: ACR122U with Mac OSX: unable to claim USB interface

Hi everyone

I'm really new to this stuff and I searched the forums for this issue but the answers have been to complicated for a newbie. I'm trying to use ACR122U with Mac OSX. I installed libnfc via brew and also the latest drivers from the manufacturer.
When I run pcsctest everything is ok. But when I try to use libnfc (for example command "lsnfc") I get these error message:

error    libnfc.driver.acr122_usb    Unable to claim USB interface (Permission denied)
ERROR: Unable to connect to NFC device.

For me, it seems that libnfc is using the wrong driver but I don't know how to change it.
Hope anybody can help me.

Thanks in advance and have a nice weekend!

Re: ACR122U with Mac OSX: unable to claim USB interface

Have you solved the problem?

I have the same error on OS X El Capitan.
I have tried libnfc 1.7.1 and 1.7.0 but no change.
Can anybody help?

Here my output:
>sudo LIBNFC_LOG_LEVEL=3 nfc-list -v
Password:
debug    libnfc.config    key: [allow_intrusive_scan], value: [yes]
debug    libnfc.config    Unable to open directory: /usr/local/Cellar/libnfc/1.7.0/etc/nfc/devices.d
debug    libnfc.general    log_level is set to 3
debug    libnfc.general    allow_autoscan is set to true
debug    libnfc.general    allow_intrusive_scan is set to true
debug    libnfc.general    0 device(s) defined by user
nfc-list uses libnfc 1.7.0
debug    libnfc.general    0 device(s) found using arygon driver
debug    libnfc.general    0 device(s) found using pn532_uart driver
debug    libnfc.general    0 device(s) found using ACR122S driver
debug    libnfc.driver.acr122_usb    device found: Bus 250 Device 004 Name ACS ACR122
debug    libnfc.general    1 device(s) found using acr122_usb driver
debug    libnfc.general    1 device(s) found using acr122_pcsc driver
debug    libnfc.general    0 device(s) found using pn53x_usb driver
debug    libnfc.driver.acr122_usb    3 element(s) have been decoded from "acr122_usb:250:004"
error    libnfc.driver.acr122_usb    Unable to claim USB interface (Permission denied)
debug    libnfc.general    Unable to open "acr122_usb:250:004".
nfc-list: ERROR: Unable to open NFC device: acr122_usb:250:004
debug    libnfc.driver.acr122_pcsc    Attempt to open ACS ACR122U
debug    libnfc.driver.acr122_pcsc    PCSC connect failed
debug    libnfc.general    Unable to open "acr122_pcsc:ACS ACR122U".
nfc-list: ERROR: Unable to open NFC device: acr122_pcsc:ACS ACR122U

Re: ACR122U with Mac OSX: unable to claim USB interface

Hello,

I also get the same problem and the same messages.
How can we solve it ?

Re: ACR122U with Mac OSX: unable to claim USB interface

Hi all,

I have posted a solution for this issue here: github.com/nfc-tools/libnfc/issues/330#issuecomment-190913731

Regards,
Johan