GOSUB 200 - The FTDI Device Driver 

I apologize for the interruption, but after spending a few hours on the 'net looking for a solution, I need to put down the information I've found in a spot where I can find it.  And that's right here.


If it's not broken...
With kernel 3.12, the FTDI device driver was changed to remove the ability to pass in a vendor and product ID.  The Eaton Home Heartbeat system has an FTDI USB-Serial chip embedded in it, with a product ID that's unknown to the current device driver.  

Earlier device driver releases let you overcome that by passing in the two new IDs:

root@pi# modprobe ftdi_sio vendor=0x0403 product=0xde29


That doesn't work anymore.  The correct way, as of this writing in July 2014, is to do the following. With device unplugged, go root, then:

root@pi# modprobe ftdi_sio
root@pi# echo 0403 DE29 > /sys/bus/usb-serial/drivers/ftdi_sio/new_id

These two command should execute without error and return immediately. If they do not, something else is amiss.

Try these manually at first to gain confidence that things are working.  Once you're sure, you can automate the driver configuration at boot time.

(Boot. Das Boot. Go SUB. Submarine, Das Boot. Get it? Huh???  Right???


I tell you, it all hangs together. I know at times it seems like a huge stretch, but I want you to know I take this whole 'blogging' stuff seriously!


If I didn't, I wouldn't kill hours searching for a movie poster about an obscure film with subtitles.)

Loading the FTDI Device Driver at (Das) Boot Time

You need two new files, a shell script and a udev rules file.  Create this shell script (owned by root:root) and plunk it in /etc (name it what you wish. Mine's named "hhb_ftdi.sh"

#!/bin/sh
/sbin/modprobe -r ftdi_sio
/sbin/modprobe ftdi_sio
echo 0403 de29 > /sys/bus/usb-serial/drivers/ftdi_sio/new_id

Now move into /etc/udev/rules.d and create a rules file. Mine's called "95-hhb_ftdi.rules"

# Rules for hotplugging Eaton Home Heartbest with FTDI (0x0403 0xDE29) Serial Adapter

SUBSYSTEM=="usb", ATTR{idVendor}=="0403", ATTR{idProduct}=="de29", RUN="/etc/hhb_ftdi.sh"

#

# These may be necessary to setup the correct permissions

KERNEL=="ttyUSB0", SYMLINK="hhb", GROUP="dialout", MODE="0660"

# KERNEL=="ttyUSB1", GROUP="dialout", MODE="0660"

The name of the rules file isn't too important. Just make sure it ends with ".rules".

Note the following - use "ATTR{idVendor}" not "SYSFS{idVendor}" as you'll find it out on the 'net.  ATTR has replaced SYSFS.  You'll get an error in /var/log/daemon.log stating "SYSFS{iDVendor} unknown key" or something to that effect.

Watch your "==" placement. Don't use the assignment "=" operator.  Check your spelling!

Note that this rule fires off the shell script.  Make sure the names match!  Note that I create a symbolic link, "/dev/hhb" to "/dev/ttyUSB0".  You don't have to do that if you don't want to.  In fact, start with the KERNEL line commented back out and see what you get.

Debugging udev rules is a known challenge.  Scan the kernel, syslog and daemon.log in /var/log for errors if things aren't working.

If all goes well, you're Eaton Home Heartbeat device will be ready and waiting for you on either port "/dev/ttyUSB0" or "/dev/hhb" when you reboot.