usb_get_string — gets a string descriptor
int usb_get_string ( | struct usb_device * | dev, |
unsigned short | langid, | |
unsigned char | index, | |
void * | buf, | |
int | size) ; |
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”?
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.