Run script on USB Ethernet gadget plugged in

[yukky]

Hello,

Hardware: RT-N66U
Firmware: 380.62

I am trying to connect a Raspberry Pi Zero device as an Ethernet gadget via the USB port on the router. Everything works, except I need to manually put the usb0 interface up and add it to the br0 bridge. How can I automate this?

When plugging in the device:

usb 1-1.2: new high speed USB device using ehci_hcd and address 5
hub 1-1:1.0: unable to enumerate USB device on port 2
usb 1-1.2: new high speed USB device using ehci_hcd and address 6
hub 1-1:1.0: unable to enumerate USB device on port 2
usb 1-1.2: new high speed USB device using ehci_hcd and address 7
usb 1-1.2: configuration #1 chosen from 2 choices
usb0: register 'cdc_ether' at usb-0000:00:04.1-1.2, CDC Ethernet Device, 06:b2:42:13:0d:a2

commands I would like to run upon device registered

ifconfig usb0 up
brctl addif br0 usb0

The commands need to be re-run everytime the USB gadget is plugged in/out.

What would be the best way to automate this, or is there a way to have this configuration persist?

 

[yukky]

I'm also seeing this, so I'm not sure if I should be in promiscuous mode or not...

device usb0 entered promiscuous mode
br0: port 5(usb0) entering listening state
br0: port 5(usb0) entering learning state
br0: topology change detected, propagating
br0: port 5(usb0) entering forwarding state

 

[Fitz Mutch]

I'm not sure if I should be in promiscuous mode

I think promiscuous mode is normal. See this:

dmesg|grep prom

 

[yukky]

Right, everything is in promiscuous mode.

Any clue about running a script on USB connect? Perhaps via hotplug2?

 

[sfx2000]

Hotplug would be the best option, IMHO, and then build a rule in the /etc/hotplug.d/iface directory...

OpenWRT has a nice hotwo over in their wiki that might be helpful

https://wiki.openwrt.org/doc/techref/hotplug

 

[john9527]

There's an undocumented (deprecated) function to run scripts via hotplug. It may be enough to do what you need. See this post....you want bullet 3
http://www.snbforums.com/threads/using-entware-optware-on-stock-firmware.8715/

 

[yukky]

Thanks john9527. I can see this is still in the codebase:
https://github.com/RMerl/asuswrt-merlin/search?utf8=✓&q=script_usbhotplug
and looks to be an example here:
http://www.snbforums.com/threads/laserjet-1020-on-rt-ac87u.19983/
.. and hey, thats your post !

Maybe a good idea to just have script_usbhotplug to run a script from /jffs/ so its easily visible in the filesystem.

 

[yukky]

I've got everything working now!

I didn't have any luck with script_usbhotplug in nvram

/jffs/scripts/init-start

#!/bin/sh

# Replace hotplug2 rules with our own, and restart hotplug2
ln -sf /jffs/hotplug2.rules /etc/hotplug2.rules
killall hotplug2

/jffs/hotplug2.rules
line added for SUBSYSTEM == net

DEVPATH is set, ACTION == add {
makedev /dev/%DEVICENAME% 0644
}
SUBSYSTEM ~~ ^(usb|tty|block|scsi_generic)$, ACTION == remove {
remove /dev/%DEVICENAME%
}
MODALIAS is set, ACTION == add {
exec /sbin/modprobe -q %MODALIAS% ;
}
SUBSYSTEM == usb, DEVICENAME ~~ ^([1-3]-[1-3][:.0-9]*+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_usb_interface %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == usb, DEVICENAME ~~ ^(lp[0-9]+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_lp %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == tty, DEVICENAME ~~ ^(ttyUSB[0-9]+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_tty %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == tty, DEVICENAME ~~ ^(ttyACM[0-9]+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_tty %DEVICENAME% %ACTION% ;
}
DEVICENAME ~~ ^(sg[0-9]+)$, ACTION == add {
exec /sbin/asus_sg %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == block, DEVICENAME ~~ ^(sr[0-9]+)$, ACTION == add {
exec /sbin/asus_sr %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == block, DEVICENAME ~~ ^(sd[a-z][0-9]*+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_sd %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == block, DEVICENAME ~~ ^(mmcblk[0-9]p[0-9]*+)$, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_mmc %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == usb, DEVICENAME == usbbcm, ACTION ~~ ^(add|remove)$ {
exec /sbin/asus_usbbcm %DEVICENAME% %ACTION% ;
}
SUBSYSTEM == net, ACTION is set {
exec /sbin/hotplug %SUBSYSTEM% ;
exec /jffs/scripts/script_hotplug.sh ;
}
SUBSYSTEM == misc, DEVICENAME ~~ ^(tun|tap)$, DEVPATH is set, ACTION == add {
exec mkdir -p -m 0777 /dev/net ;
symlink /dev/%DEVICENAME% /dev/net/%DEVICENAME%
}

/jffs/scripts/script_hotplug.sh

#!/bin/sh

echo $(date)" Action: "$ACTION" Product: "$PRODUCT" Interface: "$INTERFACE >> /tmp/hotplug.log

if [ "${INTERFACE}" = "usb0" ]; then
  if [ "${ACTION}" = "add" ]; then
    ifconfig usb0 up
    brctl addif br0 usb0
  fi
fi

Thanks for the help all!

 

[sfx2000]

I've got everything working now!

good to hear... thanks for sharing, and to the collective on the specifics..

 

[Fitz Mutch]

Is there a unique ID for the USB device? How would I recognize a specific USB device?

 

[yukky]

Is there a unique ID for the USB device? How would I recognize a specific USB device?

You can check the line that gets added to /tmp/hotplug.log, however in my case with the USB ethernet gadget, I only get:

Fri Sep 30 19:44:12 DST 2016 Action: add Product:  Interface: usb0
Fri Sep 30 19:53:33 DST 2016 Action: remove Product:  Interface: usb0

$PRODUCT is unfortunately blank for me.

The OpenWrt Hotplug wiki page says you can try to grab this information:

logger -t DEBUG "hotplug usb: action='$ACTION' devicename='$DEVICENAME' devname='$DEVNAME' devpath='$DEVPATH' product='$PRODUCT' type='$TYPE' interface='$INTERFACE'"