USB Devices

Universal Serial Bus (USB) devices were developed to provide a method to attach peripheral devices such as keyboards, printers, cameras, and disk drives using a common connector and interface. Furthermore, USB devices are hot-pluggable, which means they can be connected or disconnected while the system is running. The operating system automatically detects when a USB device has been connected and automatically configures the operating environment to make it available.

The Solaris 10 operating environment supports USB devices on Sun Blade, Netra, Sunfire, and x86/x64-based system. In addition, a USB interface can be added to Sun systems that may not already have one.

When hot-plugging a USB device, the device is immediately displayed in the device hierarchy. For example, a full device pathname for a USB Zip drive connected to an Ultra system would appear as follows:

/pci@1f,4000/usb@5/storage@1

A printer would look like this:

/pci@1f,4000/usb@5/hub@3/printer@1

Be careful when removing USB devices, however. If the device is being used when it is disconnected, you will get I/O errors and possible data errors. When this happens, you'll need to plug the device back in, stop the application that is using the device, and then unplug the device.

As stated in the "Volume Management" section later in this chapter, removable media such as floppy diskettes and CD-ROMs can be inserted and automatically mounted. When attaching a hot-pluggable device, it's best to restart vold after attaching the USB device as follows: pkill -HUP vold

Once vold identifies that the device has been connected, you'll see device names set up as follows:

zip1 -> /vol/dev/rdsk/c2t0d0/fat32        (USB Zip device)
zip0 -> /vol/dev/rdsk/c1t0d0/zip100       (USB Zip device)
jaz0 -> /vol/dev/rdsk/c3t0d0/jaz1gb       (USB Jaz device)

When disconnecting a USB device such as a Zip drive, unmount the device, stop vold, disconnect the device, and then restart vold as follows:

1.	Stop any application that is using the device.
2.	Unmount the USB device using the `volrmmount` command as follows: volrmmount -e zip0 or the `eject` command as follows: eject zip0 `zip0` is a nickname for the Zip device. The following nicknames are recognized: fd /dev/rdiskette fd0 /dev/rdiskette fd1 /dev/rdiskette1 diskette /dev/rdiskette diskette0 /dev/rdiskette0 diskette1 /dev/rdiskette1 rdiskette /dev/rdiskette rdiskette0 /dev/rdiskette0 rdiskette1 /dev/rdiskette1 floppy /dev/rdiskette floppy0 /dev/rdiskette0 floppy1 /dev/rdiskette1 cdrom0 /vol/dev/rdsk/cXtYdZ/label zip0 /vol/dev/rdsk/cXtYdZ/label jaz0 /vol/dev/rdsk/cXtYdZ/label rmdisk0 /vol/dev/rdsk/cXtYdZ/label The `-e` option simulates the ejection of the media. For a more up-to-date listing of nicknames that might have been added since this writing, consult the `volrmmount` man page.
3.	As root, stop `vold`: /etc/init.d/volmgt stop
4.	Disconnect the USB device.
5.	Start `vold`: /etc/init.d/volmgt start

For more information on vold and USB devices, see the section titled "Volume Management" later in this chapter .