I am running openocd on a Fedora Core 6 Linux box.
Everything works fine except I seem to have to run as root to make it work. Is there a way to setup my box so I don’t have to run as root ?
To use USB serial ports, I run chown /dev/ttyUSB0 and then I can use them as a regular user.
Is there something similar for this device ?
Thanks
Hi,
see this recent thread http://www.sparkfun.com/cgi-bin/phpbb/v … php?t=5676 for a discussion on how this can be achieved. I don’t know if this is going to work as is for Fedora, but you should be able to see how it’s done.
Regards,
Dominic
Thanks for the tip, Dominic. I almost have it working.
I found this page helpful.
http://www.reactivated.net/writing_udev … erminology
The thread you sent me to had the rules file named “45-ft2232.rules”. Just a heads up that that file name might not work depending what is in the later scanned files, ie those starting with a number greater than 45. In my case the general rules file for my system started with 50 and it reassigned the permissions for USB devices.
So, I renamed my file to be 55-myusb.rules and it goes as follows:
#OLIMEX Debugger
SYSFS{idProduct}==“0003”, SYSFS{idVendor}==“15ba”, MODE=“777”, OWNER=“me”, GROUP=“users”
#PL2303 USB SERIAL DEVICES
SYSFS{idProduct}==“2303”, SYSFS{idVendor}==“067b”, MODE=“664”, OWNER=“me”, GROUP=“users”
It seems to have worked, because a) the permissions work for ttyUSB* devices now, which is a great thing in itself and b) I have this in /dev/
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep00
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep02
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep04
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep81
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep83
And yet, I get this when I try to run openocd:
$ openocd -d3
Info: openocd.c:84 main(): Open On-Chip Debugger (2006-11-22 14:00 CEST)
Debug: jtag.c:1217 jtag_init():
Debug: ft2232.c:1244 ft2232_init(): ‘ft2232’ interface using FTD2XX with ‘olimex-jtag’ layout
Error: ft2232.c:1286 ft2232_init(): unable to open ftdi device: 2
If I run as root, it works fine. Is there something else I need to set other than the USB port permissions ?
/usr/lib
lrwxrwxrwx 1 root root 34 Jan 16 15:08 libftd2xx.so.0 → /usr/local/lib/libftd2x
/usr/local/lib
lrwxrwxrwx 1 root root 19 Jan 16 14:52 libftd2xx.so → libftd2xx.so.0.4.13
-rwxr-xr-x 1 root root 319466 Jan 16 14:52 libftd2xx.so.0.4.13
What am I missing ?
As I wrote in the thread Dominic pointed you to, libftd2xx operates on /proc/bus/usb/...armdeveloper:
It seems to have worked, because a) the permissions work for ttyUSB* devices now, which is a great thing in itself and b) I have this in /dev/crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep00
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep02
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep04
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep81
crwxrwxrwx 1 me users 442, 2054 Jan 18 11:52 /dev/usbdev2.7_ep83
And yet, I get this when I try to run openocd:
$ openocd -d3
Info: openocd.c:84 main(): Open On-Chip Debugger (2006-11-22 14:00 CEST)
Debug: jtag.c:1217 jtag_init():
Debug: ft2232.c:1244 ft2232_init(): ‘ft2232’ interface using FTD2XX with ‘olimex-jtag’ layout
Error: ft2232.c:1286 ft2232_init(): unable to open ftdi device: 2
If I run as root, it works fine. Is there something else I need to set other than the USB port permissions ?
Please note, this is proc, not dev. Unfortunately, I don’t know how to change owner/permissions on /proc/bus/usb/xxx via udev :-(. So I keep chown/chmod it by hand 
Please check owner/permissions on the corresponding files in the /proc hierarchy.
Darn… I missed reading about the permissions on /proc/bus/usb !
I checked the permissions on /dev/bus/usb and they are fine. But the /proc/bus/usb permissions were still root !
I did a chown on them and now I can run openocd as a regular user.
I’ll figure out how to change the proc permissions in udev and post it here later on.
Hi
This can be done with the mount options for /proc/bus/usb
The relevant lines in /etc/fstab are:
none /proc proc defaults 0 0
none /proc/bus/usb usbfs defaults,devmode=0666 0 0
Some distributions does not mount /proc/dev/usb from /etc/ fstab but from other startupfiles,
so on fc5 I had to add the following to /etc/rc.local
Remount /proc/bus/usb to make fstab options (devmode=0666) active
mount -o remount /proc/bus/usb
Of course all /proc/bus/usb ebtries are now rw which is not a problem on a single user machine.
Regards,
Magnus
I was working on the approach outlined here:
http://www.owfs.org/index.php?page=udev
I wonder if there is a way to do it directly from a udev rules file, without the script like they did it ? I don’t like the idea of modding rc.local, but maybe that is just me.
I would say that chages to udev rules that run permission granting script are more error prone and potentially more dangerous than a remonut in rc.local
I cannot say that I ever really understod the udev rules, to much magic for me.
Magnus
I guess you have a point.