Provided by:
linux-doc-2.6.15_2.6.15-23.39_all 
NAME
usb_get_string - gets a string descriptor
SYNOPSIS
int usb_get_string (struct usb_device * dev, unsigned short langid,
unsigned char index, void * buf, int size);
ARGUMENTS
dev the device whose string descriptor is being retrieved
langid code for language chosen (from string descriptor zero)
index the number of the descriptor
buf where to put the string
size how big is ‘‘buf’’?
CONTEXT
!in_interrupt ()
DESCRIPTION
Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per
character, in little-endian byte order). The usb_string function will
often be a convenient way to turn these strings into kernel-printable
form.
Strings may be referenced in device, configuration, interface, or other
descriptors, and could also be used in vendor-specific ways.
This call is synchronous, and may not be used in an interrupt context.
Returns the number of bytes received on success, or else the status
code returned by the underlying usb_control_msg call.