As you may recall, at Anybots USB was the backbone of our bot.
And as no one wanted to tackle the USB, besides John and I,
it fell to me to read the Spec. John can tell you as much as I
can USB is a basket case and a bastard child.

To accomplish your task I would suggest running your
task in user space (with privileges of course). 

USB requires timing, negative-timing, fallbacks and timeouts.
It is not pretty. Perhaps in 5-10 years we can kill the
negative-timing and fallbacks, with some confidence
that USB 1.0 are no longer available and cannot be
plugged in to new devices.

timing, fallbacks and timeouts are straightforward.

negative-timing requires that you guess if a 1.0 device
might have been attached to bus. Most MFGs ignore
this, and either fuck the device or fuck the bus. Recovery
requires that your USB bus (or hub) allows you to reset it.
Which if you've fucked the bus, means you have to
guess when the device was removed and recover
in a normal method.

Hope this helps.

On Fri, 11/28/14, Alfred Perlstein <> wrote:

 Subject: Re: Question on ue devices autoconfigure versus Linux.
 To: "Jesus Monroy" <>,
 Cc: "Hans Petter Selasky" <>
 Date: Friday, November 28, 2014, 6:16 PM
 Well sure, but we have devd in
 FreeBSD for some time.  It actually does 
 handle the hot plug (sort-of...) I made a custom devd hook
 for it.
 The actual problem is that if I boot FreeBSD with the device
 plugged in 
 then devd never runs my hooks.
 That and I'm not sure if devd is even the right place... to
 put my 
 hooks, but it sure seems like it... except for the "doesn't
 show up at 
 Also really interested in knowing how the heck Linux figures
 out the IP 
 Is there some usb ethernet spec for autoconfiguring???
 On 11/28/14, 5:05 PM, Jesus Monroy wrote:
 > Alfred,
 > I usually don't get the USB mailing list in my inbox.
 > for some reason I fished this out of spam. Indicating
 to me
 > I should answer this.
 > Hot swapping has never been a strong point for BSD.
 > Basically they think, "hot swapping" means, flip a
 > mechanical switch, remove the device. They DON'T
 > think like a USB device; which is "plug in and pull"
 > - at will.
 > In the Linux world, there is an army of people that
 > attack problems like this 'ad hoc'. The BSD
 > community is far too formal to get it done in
 > any reasonable time frame.
 > In the Linux world, there are a host of "post-boot"
 > solutions, such as systemd, busd, etc. They all
 > generally trap an event, be it real (such as an IRQ),
 > network, program, or user.  This is usually
 > leverage by /proc, dmesg or similar.
 > Hope this helps.
 > FWIW: I'm living in El Paso Texas for the next 6
 > Best of Luck,
 > Jesse
 > --------------------------------------------
 > On Fri, 11/28/14, Alfred Perlstein <>
 >   Subject: Question on ue devices
 autoconfigure versus Linux.
 >   To:
 >   Cc: "Hans Petter Selasky" <>
 >   Date: Friday, November 28, 2014, 5:37
 >   Hello,
 >   We have a widget here, basically a
 "beagleclone" that runs
 >   Linux.
 >   When I plug it into an ubuntu host it
 shows up as:
 >   usb0      Link
 encap:Ethernet  HWaddr
 >   8a:18:9f:c4:a9:02
 >              inet
 >   addr: 
 >   Mask:
 >              inet6
 >   fe80::8818:9fff:fec4:a902/64
 >              UP
 >              RX
 >   errors:0 dropped:0 overruns:0 frame:0
 >              TX
 >   errors:0 dropped:0 overruns:0
 >   txqueuelen:1000
 >              RX
 >   (626.0 B)  TX bytes:10727 (10.7
 >   Requires no special setup.
 >   However on a FreeBSD machine I need to
 do this:
 >   USBDEV=$(shell dmesg | grep
 '^ugen.*LCD' | sed -E
 >   's/^ugen([0-9]+\.[0-9]+).*/\1/')
 >   # target to make the device show up on
 >   config-freebsd:
 >            usbconfig -d
 >   $(USBDEV) set_config 1
 >            sleep 5
 >            ifconfig ue0
 >  up
 >   Basically I need to grep dmesg for
 "ugen" and the string
 >   "LCD", then I
 >   need to run:
 >     usbconfig -d 3.3 set_config
 1  # (3.3 comes from
 >   dmesg)
 >     then..
 >     ifconfig ue0 inet  up
 >   Any idea why Linux can do this all
 automagically but FreeBSD
 >   needs
 >   manual help?
 >   I even tried putting some stuff into
 devd.conf, however devd
 >   doesn't
 >   seem to the right thing if the device
 is plugged in at boot
 >   time. This
 >   is because devd only seems to know
 when a device is plugged
 >   in, however
 >   it doesn't trigger events when the
 device has been present
 >   since boot.
 >   Any tips on this?  We can get
 around this with some
 >   custom rc scripts,
 >   but I was just wondering if FreeBSD
 could make it more plug
 >   and play.
 >   thanks,
 >   -Alfred
 >   _______________________________________________
 >   mailing list
 >   To unsubscribe, send any mail to ""
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