#include <u.h>#include <libc.h>#include <thread.h>#include "usb.h" intDfmt(Fmt *f){	Device *d; 	d = va_arg(f->args, Device*);	if(d == nil)		return fmtprint(f, "<null device>");	return fmtprint(f, "usb%d/%d", d->ctlrno, d->id);} voidusbfmtinit(void){	fmtinstall('D', Dfmt);}