linux USB issues

May 06, 2013, 09:12:36 pm

Hello,

I've got an older OLS device (v1.01) that has sat unused for a while. When I went to pull it out over the weekend I found that my present computer is very unhappy with it.

After some initial problems involving the modem-manager and a kernel oops, I found this page: http://dangerousprototypes.com/docs/Log ... uide#Linux
I was able to add the udev rule and avoid the problem with modem-manager.

Now, however, I still get two devices showing up when I plug the OLS into my machine, /dev/ttyUSB1 and /dev/ttyUSB2.

dmesg shows that are some issues with the ftdi driver, most interestingly (I think) is "Unable to read latency timer: -32".
It seems odd to me that this device would use the ftdi driver anyway, since the usb stack is running natively on the PIC as far as I know.

Output from dmesg:

Code: [Select]

[ 1297.730651] usb 2-1.5.4: new full speed USB device using ehci_hcd and address 11
[ 1297.844002] usb 2-1.5.4: configuration #1 chosen from 1 choice
[ 1297.844679] ftdi_sio 2-1.5.4:1.0: FTDI USB Serial Device converter detected
[ 1297.844716] usb 2-1.5.4: Detected FT2232C
[ 1297.844719] usb 2-1.5.4: Number of endpoints 1
[ 1297.844723] usb 2-1.5.4: Endpoint 1 MaxPacketSize 8
[ 1297.844726] usb 2-1.5.4: Setting MaxPacketSize 8
[ 1297.844870] ftdi_sio ttyUSB1: Unable to read latency timer: -32
[ 1297.844928] usb 2-1.5.4: FTDI USB Serial Device converter now attached to ttyUSB1
[ 1297.845014] ftdi_sio 2-1.5.4:1.1: FTDI USB Serial Device converter detected
[ 1297.845036] usb 2-1.5.4: Detected FT2232C
[ 1297.845038] usb 2-1.5.4: Number of endpoints 2
[ 1297.845040] usb 2-1.5.4: Endpoint 1 MaxPacketSize 64
[ 1297.845042] usb 2-1.5.4: Endpoint 2 MaxPacketSize 64
[ 1297.845044] usb 2-1.5.4: Setting MaxPacketSize 64
[ 1297.845245] ftdi_sio ttyUSB2: Unable to read latency timer: -32
[ 1297.845303] usb 2-1.5.4: FTDI USB Serial Device converter now attached to ttyUSB2
[ 1297.877859] ftdi_sio ttyUSB2: Unable to write latency timer: -32
[ 1297.878337] ftdi_sio ttyUSB2: ftdi_set_termios FAILED to set databits/stopbits/parity
[ 1297.878585] ftdi_sio ttyUSB2: ftdi_set_termios urb failed to set baudrate
[ 1297.879085] ftdi_sio ttyUSB2: urb failed to clear flow control
[ 1297.879584] ftdi_sio ttyUSB2: ftdi_set_termios urb failed to set baudrate
[ 1297.879833] ftdi_sio ttyUSB2: urb failed to clear flow control
[ 1297.880088] ftdi_sio ttyUSB2: ftdi_set_termios error from disable flowcontrol urb
[ 1297.880582] ftdi_sio ttyUSB2: urb failed to clear flow control
[ 1297.979943] ftdi_sio ttyUSB2: ftdi_set_termios urb failed to set baudrate
[ 1297.980561] ftdi_sio ttyUSB2: urb failed to clear flow control
[ 1310.512118] ftdi_sio ttyUSB2: error from flowcontrol urb
[ 1393.179458] usb 2-1.5.4: USB disconnect, address 11
[ 1393.179609] ftdi_sio ttyUSB1: FTDI USB Serial Device converter now disconnected from ttyUSB1
[ 1393.179624] ftdi_sio 2-1.5.4:1.0: device disconnected
[ 1393.179735] ftdi_sio ttyUSB2: FTDI USB Serial Device converter now disconnected from ttyUSB2
[ 1393.179748] ftdi_sio 2-1.5.4:1.1: device disconnected

Anyone have any suggestions?
-Matt

Re: linux USB issues

Reply #1 – July 04, 2013, 11:18:13 pm

This certainly looks wrong (that the logic sniffer gets identified as a FTDI rs232 device). Well, it is wrong actually.
This looks like an old linux kernel. What kernel is/was this? My bet is that upgrading to something more recent
will straighten things out unless your udev setup has been strangely customized. It is odd that the vendor and
device id stuff is not getting displayed, which is what I see with my setup (Fedora 18 with a 3.9.6 kernel).
My logic sniffer gets set up as ttyACM0.

And yes I see this is a several month old post (that nobody answered?), but I just joined the forum today.

Re: linux USB issues

Reply #2 – July 08, 2013, 09:00:34 am

Very strange. The OLS is a USB CDC (virtual serial) device. It should be assigned the default system driver and not anything FTDI related.