sispmctl – using it as non root

Hello,
in my article sispmctl I worked as root all the time. I would prefer to use “sispmctl” as normal user (and without sudo). My solution is to change the group of the entry for the power outlet in /dev/usbdev* to “plugdev”.

(By the way, this “hack” was created and tested on a Debian Lenny system.)

Check if the user is a member of the group plugdev:

crissa@unseen:~$ grep crissa /etc/group
[...]
plugdev:x:46:crissa
[...]

If your user isn’t a member of the group “plugdev” you can add him with “adduser plugdev”.

Get more information about the power outlet:

unseen:~# lsusb -v
[...]
Bus 001 Device 027: ID 04b4:fd13 Cypress Semiconductor Corp. 
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0         8
  idVendor           0x04b4 Cypress Semiconductor Corp.
  idProduct          0xfd13
  bcdDevice            1.01
  iManufacturer           1 Gembird Electronics
  iProduct                2 Gembird Silver Shield PM
 [...]

The ipVendor and idProduct can be used to identify the power outlet.

Add an entry to the file local.rules in the directory /etc/udev/rules.d:

# 20110105 crissa  sispmctl
SYSTEM=="usb", ATTRS{idVendor}=="04b4", ATTRS{idProduct}=="fd13", GROUP="plugdev"

# eof

I prefer to create an extra file for my own entries.

Restart udev to load the new udev rules:

unseen:~# /etc/init.d/udev restart
Stopping the hotplug events dispatcher: udevd.
Starting the hotplug events dispatcher: udevd.

Check /dev/usbdev* for a plugdev entry:

unseen:~# ls -l /dev/usbdev* | grep plugdev

Plug in the power outlet and check again:

unseen:~# ls -l /dev/usbdev* | grep plugdev
crw-rw---- 1 root plugdev 252, 8 2011-01-05 22:22 /dev/usbdev1.28_ep00

The final test as (non root) user:

crissa@unseen:~$ sispmctl -m all
Accessing Gembird #0 USB device 028
Power supply status is: off
Power supply status is: off
Power supply status is: off
Power supply status is: off
crissa@unseen:~$ sispmctl -o 1
Accessing Gembird #0 USB device 028
Switched outlet 1 on
crissa@unseen:~$ sispmctl -m all
Accessing Gembird #0 USB device 028
Power supply status is: on
Power supply status is: off
Power supply status is: off
Power supply status is: off

Feel free to create a new group (maybe “sispmctl”) for the power outlet user. I don’t need an extra group so the group “plugdev” is fine with me, at least for now.
Bye, Tore