open_pipe
.open_pipe = dwc2_open,
.open_pipe = ehci_open,
.open_pipe = ohci_open,
.open_pipe = uhci_open,
err = dev->bus->methods->open_pipe(p);
usbd_status (*open_pipe)(struct usbd_pipe *);
.open_pipe = xhci_pipe_open,
fd = open_pipe(path);
static int open_pipe(char *);