Fedora 11: Using USB UART Devices Like FTDI FT232R

[Robert L Cochran]

If you like playing with Arduino devices, like I do, you need to have 
serial port access. These days the easiest way to do that is over USB. 
Under Fedora 11, If you plug in an FTDI FT232R uart in order to get 
serial access over USB, the resulting device could show up with these 
permissions:

# ls -al /dev/ttyUSB*
crw-rw----. 1 root dialout 188, 0 2009-05-03 10:24 /dev/ttyUSB0

To actually have access to the device, the user must become a member of 
the dialout group. Once you add yourself to the group, you log out and 
log in and access is magically granted.

This restriction is not consistent with how Fedora 10 works. I didn't 
have this problem there.

For context, here are the kernel messages I got when I plugged in the 
device:

May  3 10:24:15 deafeng3 kernel: usb 6-1: new full speed USB device 
using uhci_hcd and address 2
May  3 10:24:16 deafeng3 kernel: usb 6-1: New USB device found, 
idVendor=0403, idProduct=6001
May  3 10:24:16 deafeng3 kernel: usb 6-1: New USB device strings: Mfr=1, 
Product=2, SerialNumber=3
May  3 10:24:16 deafeng3 kernel: usb 6-1: Product: FT232R USB UART
May  3 10:24:16 deafeng3 kernel: usb 6-1: Manufacturer: FTDI
May  3 10:24:16 deafeng3 kernel: usb 6-1: SerialNumber: A8007UF2
May  3 10:24:16 deafeng3 kernel: usb 6-1: configuration #1 chosen from 1 
choice
May  3 10:24:16 deafeng3 kernel: usbcore: registered new interface 
driver usbserial
May  3 10:24:16 deafeng3 kernel: USB Serial support registered for generic
May  3 10:24:16 deafeng3 kernel: usbcore: registered new interface 
driver usbserial_generic
May  3 10:24:16 deafeng3 kernel: usbserial: USB Serial Driver core
May  3 10:24:16 deafeng3 kernel: USB Serial support registered for FTDI 
USB Serial Device
May  3 10:24:16 deafeng3 kernel: ftdi_sio 6-1:1.0: FTDI USB Serial 
Device converter detected
May  3 10:24:16 deafeng3 kernel: usb 6-1: Detected FT232RL
May  3 10:24:16 deafeng3 kernel: usb 6-1: FTDI USB Serial Device 
converter now attached to ttyUSB0
May  3 10:24:16 deafeng3 kernel: usbcore: registered new interface 
driver ftdi_sio
May  3 10:24:16 deafeng3 kernel: ftdi_sio: v1.4.3:USB FTDI Serial 
Converters Driver
May  3 10:24:16 deafeng3 NetworkManager: <info>  (ttyUSB0): ignoring due 
to lack of mobile broadband capabilties
May  3 10:37:14 deafeng3 yum: Installed: avrdude-5.5-4.fc11.x86_64
May  3 10:47:06 deafeng3 pcscd: winscard.c:309:SCardConnect() Reader 
E-Gate 0 0 Not Found
May  3 10:47:06 deafeng3 pcscd: winscard.c:309:SCardConnect() Reader 
E-Gate 0 0 Not Found
May  3 10:47:06 deafeng3 pcscd: winscard.c:309:SCardConnect() Reader 
E-Gate 0 0 Not Found
May  3 10:47:06 deafeng3 pcscd: winscard.c:309:SCardConnect() Reader 
E-Gate 0 0 Not Found


Thanks

Bob