Re: [Ftdi-usb-sio-devel] Problems with FT245 on ttyUSB0

[G.W. H. <ft...@ju...>]

Hi there,

On Thu, 18 Apr 2013, Ryan Neve wrote:

> I'm having trouble with a FT245RL based USB-relay board. ...
> I wrote a very simple python program to test this on a Debian squeeze 
> machine: ...and nothing happened no matter how much I fiddled. ...
> I'm wondering if there might be a problem with ftdi_sio?

I'm not convinced that the current ftdi_sio driver is working properly.
I've been trying to use it and it behaves, well, strangely.  I posted
a question about it here on April 5th and there's been no reply.

> #/sbin/modprobe ftdi_sio vendor=0x403 product=0x6001 debug

I did some digging and according to the latest kernel code the methods
for enabling debug information have changed.  I don't know when, so I
don't know if it affects your kernel/modules.  The documentation in
the kernel tree still refers to the old methods of enabling debugging
which give me nothing but kernel errors and cause the module not to load.

> #dmesg | grep ftdi
> [71621.091869] ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting 
> read urb, error -1
> [74607.375564] ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting 
> read urb, error -1

I'm not sure if that's debug output or normal (problem) output.

> Ftdi has a Linux driver on their web site, but I think my kernels should be 
> new enough (2.6.33.7.2-rt30-1-686 and 2.6.18-348.3.1.el5.centos.plusPAE) to 
> not need it. If I do need it, is there a guide on how to install available?

I think they might be keeping that older version of the driver on
their site because it works, but I don't know that it works.  I
haven't got a kernel old enough to try it but until I ran into some
other more pressing issues at work, after setting up a Windows VM to
try that was next idea on my list.

FWIW this list seems to be dead.

--

73,
Ged.