NAME
usb_gadget_frame_number - returns the current frame number
SYNOPSIS
int usb_gadget_frame_number (struct usb_gadget * gadget);
ARGUMENTS
gadget controller that reports the frame number
DESCRIPTION
Returns the usb frame number, normally eleven bits from a SOF packet,
or negative errno if this device doesn’t support this capability.
AUTHOR
David Brownell <dbrownell@users.sourceforge.net>.