[clue-tech] Hotplug scripts and usermaps

[Matt Gushee]

I seem to have a USB hotplugging problem.

The other day I bought a new Palm Pilot (3 or 4 years behind the times, 
as usual ;-), and I am trying to hot-sync it over a USB connection (I 
don't have a cradle, just a USB cable running directly from the Palm to 
the PC). On the PC side, I'm using pilot-link with the JPilot GUI, and I 
have kernel 2.6.10.

The basic issue I'm running into is permissions on the USB connection. 
If I run JPilot as root, there's no problem, but of course I don't want 
to do that. Or I can log in as root and set the permissions. But the 
trouble with that is that the device representing USB connection is 
temporary. In fact, it only comes into existence when I press the 
hot-sync button on the Palm Pilot. So when I want hot-sync as a regular 
user I have to be logged in as root on some console; I run JPilot, press 
the hot-sync button, switch to my root console, set the permissions on 
the device, then switch back to JPilot and do what I need to do ... it's 
completely bogus.

Apparently the right way to do this is with hotplug, and I have 
attempted to set this up but it's not working. Apparently a usermap and 
a device-specific script are required, so I copied and modified the ones 
that are installed for libsane, which enable the hotplug manager to 
correctly detect my USB scanner. So in /etc/hotplug/usb I have:

   pilot.usermap
   -------------
   # usb module         match_flags idVendor idProduct bcdDevice_lo \
       bcdDevice_hi bDeviceClass bDeviceSubClass bDeviceProtocol \
       bInterfaceClass bInterfaceSubClass bInterfaceProtocol driver_info
   visor   0x0003  0x0830  0x0060  0x0000  0x0000  0x00    0x00    0x00 

       0x00   0x00     0x00    0x00000000

   pilot
   -----
   #!/bin/sh

   # This file is part of sane-backends.
   #
   # This script changes the permissions and ownership of a USB device under
   # /proc/bus/usb to grant access to this device to users in the 
scanner group.
   #
   # Ownership is set to root:scanner, permissions are set to 0660.
   #
   # Arguments :
   # -----------
   # ACTION=[add|remove]
   # DEVICE=/proc/bus/usb/BBB/DDD
   # TYPE=usb

   # latest hotplug doesn't set DEVICE on 2.6.x kernels
   if [ -z "$DEVICE" ] ; then
     IF=`echo $DEVPATH | sed 's/\(bus\/usb\/devices\/\)\(.*\)-\(.*\)/\2/'`
     DEV=`echo $DEVPATH | sed 's/\(bus\/usb\/devices\/\)\(.*\)-\(.*\)/\3/'`
     DEV=`expr $DEV + 1`
     DEVICE=`printf '/proc/bus/usb/%.03d/%.03d' $IF $DEV`
   fi

   if [ "$ACTION" = "add" -a "$TYPE" = "usb" ]; then
     chown root:staff "$DEVICE"
     chmod 0660 "$DEVICE"
     chown root:staff /dev/usb/tts/1
     chmod 0660 /dev/usb/tts/1
   fi

   # That's an insecure but simple alternative
   # Everyone has access to the scanner

   # if [ "$ACTION" = "add" -a "$TYPE" = "usb" ]; then
   #  chmod 0666 "$DEVICE"
   # fi

This could be completely wrong: the only thing I'm sure of the the 
vendor and product IDs that I put in the usermap. I've checked the 
linux-hotplug project on SourceForge, manual pages, and other places, 
and there's very little documentation on how to do this stuff. At any 
rate, the permissions don't get set automatically.

I've also checked for log messages. There is a /var/log/hotplug 
directory, but it's empty. The only thing I've found that could be 
relevant is this message, which appears many times in /var/log/errors:

   Mar 18 16:18:57 $MY_HOSTNAME hal.hotplug[5011]: DEVPATH is not set

Anybody have a clue how I can fix this?

--
Matt Gushee
Englewood, CO, USA