54.6 UDEV

udev, udev, udev, udev, udev, udev, udev, udev, udev, udev hotplug

A problem that plagued earlier versions of the GNU/Linux kernel was that each time a USB device (and other devices) was connected a different mount point would be assigned. This issue was addressed in the 2.6 kernels using udev, udev, udev, udev, udev, udev, udev, udev, udev, udev with hotplug. With udev, udev, udev, udev, udev, udev, udev, udev, udev, udev, naming rules (e.g., in /etc/udev/rules.d/local.rules) are used to provide stable names for use in /etc/fstab. Udev, Udev, Udev, Udev, Udev, Udev, Udev, Udev, Udev, Udev uses information exported by the kernel drivers to the sysfs filesystem (usually mounted on /sys) to identify specific devices and to then associate them with specific names in /dev.

The key to using udev, udev, udev, udev, udev, udev, udev, udev, udev, udev is with the rules that are defined to identify and distinguish the different USB devices that may be connected. A tutorial for writing udev rules is available from http://www.reactivated.net/udevrules.php.

The first step is to identify the USB device in some way. The udevinfo command can be used to identify a device path, which can then be used to identify information about the device on that path. For example, to identify a specific Flash Memory device which is recognised in GNU/Linux as a SCSI device, connect the device and run the command:

  $ udevinfo -a -p $(udevinfo -q path -n /dev/sdc)

The /dev/sdc path here is whatever the dmesg command identifies. Select some identifying piece of information, like the product identifier (the line that starts with SYSFS\{product\=}), and add that to /etc/udev/rules.d/local.rules (each rule must be on a single line).

54.6.1 Flash Memory

On one line in /etc/udev/rules.d/local.rules:

  BUS=="usb", KERNEL=="sd?1", SYSFS{product}=="USB FLASH DISK", 
  NAME="%k", SYMLINK=""usbkey"

Then restart udev:

  $ sudo restart udev

Add a suitable entry to /etc/fstab:

  /dev/usbkey   /media/usbkey   auto    user,defaults       0   0

Be sure the mount point /media/usbkey exists:

  $ sudo mkdir /media/usbkey

An alternative name might be:

  BUS=="usb", KERNEL=="sd?1", SYSFS_serial=="07381C501259", NAME="usb/key%n"

54.6.2 Camera

  $ udevinfo -a -p /block/sdc
  $ sudo emacs -nw /etc/udev/rules.d/local.rules
  BUS=="usb", KERNEL=="sd?1", SYSFS{product}=="hp photosmart 320", 
  NAME="%k", SYMLINK="photosmart"
  $ sudo emacs -nw /etc/fstab
  /dev/photosmart /media/photosmart auto user,defaults  0   0
  $ sudo mkdir /media/photosmart
  $ wajig restart udev

A Nikon Coolpix E5200 camera:

  $ udevinfo -a -p /block/sdc
  $ sudo emacs -nw /etc/udev/rules.d/local.rules
  BUS=="usb", KERNEL=="sd?1", SYSFS{product}=="NIKON DSC E5200", 
  NAME="%k", SYMLINK="nikon"
  $ sudo emacs -nw /etc/fstab
  /dev/nikon /media/nikon auto user,defaults    0   0
  $ sudo mkdir /media/nikon
  $ wajig restart udev

For some reason /dev/sdc1 is not created when the camera is plugged in (/dev/sdc is). But after an attempt to mount /dev/sdc, /dev/sdc1 comes into existence (even though the mount command fails with a request to specify the filesystem type). After installing the gnome-volume-manager /dev/sdc1 started being created.

54.6.3 iPod

The following udev rule will create a symbolic link called ipod in /dev/ to the data partition on an iPod when it is plugged in:

  BUS=="scsi", SYSFS{model}=="iPod", KERNEL=="sd?3", NAME="%k", SYMLINK="ipod"

54.6.4 Card Reader

For a card reader they usually do not provide media change information and so the kernel can not generate a hotplug event for udev. In this situation you can use the all_partitions property for the NAME. To get access to a CF slot on a specific multi-card reader:

  BUS=="scsi", SYSFS{vendor}=="Zynet*", SYSFS{model}=="USB Storage-CFC*", 

54.6.5 MP3 Player iRiver H340

An iRiver H300 Series MP3/ogg HDD player (H340):

  $ udevinfo -a -p /block/sdc | grep product
    SYSFS{product}="iRiver H300 Series"
    SYSFS{product}="Intel Corp. 82801EB/ER ..."
  $ sudo emacs -nw /etc/udev/rules.d/local.rules
  BUS=="usb", KERNEL=="sd?1", SYSFS{product}=="iRiver H300 Series", 
  NAME="%k", SYMLINK="iriver"
  $ sudo emacs -nw /etc/fstab
  /dev/iriver /media/iriver auto users,defaults     0   0
  $ sudo mkdir /media/iriver
  $ wajig restart udev
  $ mount /media/iriver iRiver ifp796

Initial connect to USB did not report anything in dmesg. By looking at /proc/bus/usb/devices found:

  T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 26 Spd=480 MxCh= 0
  D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
  P:  Vendor=4102 ProdID=1007 Rev= 0.01
  S:  Manufacturer=iRiver Limited.
  S:  Product=IFP-700 HIGH SPEED
  C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA
  I:  If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
  E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

It was being found but there is no Driver! As I understand this means that the firmware is using the Managed firmware.

So instead install ifp-line and run as root:

  $ wajig install ifp-line
  $ ifp ls
  Device is busy.  (I was unable to claim its interface.)
  $ sudo ifp ls
  f iRiver, Catch the digital flow!.mp3   (size 1988608)

This works just fine! with commands to manage the iRiver from the command line.

A decent graphics interface is ifp-manager:

  $ wget http://optusnet.dl.sourceforge.net/sourceforge/ifp-manager/ifp-manager0_2_0.tar.bz2
  $ tar xvf ifp-manager0_2_0.tar.bz2
  $ cd ifp-manager0.2.0/
  $ sudo ./ifpmanager.pl

Another graphical interface is provided by ifp-gnome. The interface is good but the functionality is limited. Seems if you select a folder of albums belonging to an artist, only the first album gets uploaded.

  $ wget http://optusnet.dl.sourceforge.net/sourceforge/ifp-gnome/ifp-gnome_0.5-ubuntu1_noarch.deb
  $ wajig install ifp-gnome_0.5-ubuntu1_noarch.deb 
  $ sudo ifp-gnome

To allow a user access to the ifp:

  $ wajig install pmp-common
  $ sudo adduser kayon plugdev

54.6.6 Ethernet Cards

 KERNEL=="eth*", SYSFS{address}=="00:00:de:ad:be:ef", NAME="eth0"
 KERNEL=="eth*", SYSFS{address}=="00:00:fe:ed:ba:be", NAME="eth1"

54.6.7 Examples

A bunch of examples from Rogrio Brito:

  # USB Key Drive: "Leading Driver Co.,LTD.", "USB Mass Storage Device" 
  BUS=="usb", SYSFS{idProduct}=="2317", SYSFS{idVendor}=="067b",
  NAME="usb/key%n", SYMLINK="sda%n"

  # Printer: "DeskJet 840C", "BR1391S0WNKV" 
  BUS=="usb", SYSFS{idProduct}=="0604", SYSFS{idVendor}=="03f0",
  NAME="usb/lp%n", SYMLINK="hp_lp"

  # iPod 
  BUS=="ieee1394", SYSFS{model_name_kv}=="iPod", NAME="ipod%n"

  # HD in Firewire Enclosure 
  BUS=="scsi", SYSFS{vendor}=="QUANTUM*", SYSFS{model}=="FIREBALLlct15 30", 

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