FIXED : Just wrote my own fix with some C code.

Hi folks

I have a piece of hardware that use the ftdi_sio kernel module.
This hardware is known for working great with the 1.4.0 version only of this module.
The reason is that any later version change the DTR to "high" when changing baudrate thus won't let me "start" it right.

I found a patch for 1.4.1 here : http://lkml.org/lkml/2005/9/22/64 , but can't find a working patch for the 1.4.3 version of this module in the 2.6.16.9 kernel. It's just a few lines, it ensures that the DTR don't changes when you set the baudrate.

I've got the ftdi_sio 1.4.0 source from linux-2.6.8 (the ftdio_sio.c and ftdio_sio.h) and need help/guidance to compile this for my present system, which is Slackware 10.2 with the 2.6.16.9 kernel package found in the latest /testing (the only update so far on the system). Or if someone have the skills to get the patch working on the 1.4.3 version of the module.

Any help/guidance here will be much appreciated.

Regards

I looked at that "drivers/usb/serial/ftdi_sio.c" file in my 2.6.15.6 kernel source tree, and the patch from the link you posted already seems to have been applied in the official kernel.

Did you try a default kernel >= 2.6.15.6 yet, just to see if it works with your hardware? If it does not work, you might have another problem than the one that patch solved.

Eric

Thank you for your answer.

I've got the 2.6.16.9 (from current), which have the 1.4.3 version of ftdi_sio.
I downloaded the 2.6.15.6 and that also included the 1.4.3 version. If you say the patch still is in that version, might it be faulty in the 2.6.16.9 with the same version number?

So now I'm a bit confused since I know for a fact that linux-2.6.8 with ftdi_sio 1.4.0 is working (tested on a debian system).
So why wont it work with 1.4.3, since the patch is applied? What else might be wrong?

I know from the instructions for the hardware that the raised DTR is the behavior that keep it from not working. So any other tips?
Other dependencies in the kernel for this ftdi_sio which might do any "harm" to this DTR thing?

The output from the debian stty settings for the tty port is also the same.
Also, there is no other modules loaded for this device.

I would like to get this working in slackware. To just use debian, because it works mysteriously, would be a shame.

Another tip that might be of interest is that it also might work if I use the pcsc-lite, as a hack for this with the faulty ftdi_sio (I believe). Do anyone know of a ftdi CCID driver for the pcsc-lite?

UPDATE:

The device is supposed to work when I do the following :
stty speed 9600 < /dev/ttyUSB0
stty cs8 < /dev/ttyUSB0
stty -cstopb < /dev/ttyUSB0

Then set the DTR "high". Now, the led on the unit should be on. It's not. followed by:

echo -n "*}" > /dev/ttyUSB0, to set it in the working modus I need. The led should now give a blink. (it does)

and then set DTR "low". (And the led should still be on)

Until now, I thought that using "stty crtscts" did set the DTR to high, and stty -crtscts put DTR in low... but... that might not be the case?
Any tip on this DTR thing?

BTW: on the working debian install, non of this is needed. Just ensure that the baud rate is 9600, then send the echo *} and everything is fine. Also with these non-working units I try on my slackware system. I'm pulling my hair out here...

Again, any info, input or suggestions is more than welcome.