On Thu, Mar 29, 2018 at 01:49:02PM +0200, Teichmann, Martin wrote:

Dear Greg, dear Johan, dear list,

I'm very sorry I was a bit quick in sending you a patch for the PI
E-870 device, because it's actually wrong. Everything seemed to work
fine, until I realized that once in a while two characters were
missing. Checking dmesg I realized error messages had piled up. It
turns out, the device is not compatible with the ftdi_sio driver in
the end. I hope this can be undone...

No worries, I just sent a revert patch to Greg.

The device, however works with a usb-serial-simple driver.
Unfortunately, it is not as easy as for the E-870 to supply a patch,
as usb-serial-simple does not just contain a list of VID and PIDs, but
actually creates a new entry somewhere in /sys/bus for each vendor. I
would like to send in patch for this later, but this time properly
tested...

Try first to determine what chip this really is (e.g. by opening the
device). Chances are there's already a driver for it. Full "lsusb -v"
might also give some clues.

Thanks,
Johan