USBHID_N_TRANSFER
struct usb_config sc_config[USBHID_N_TRANSFER];
struct usb_xfer *sc_xfer[POLL_XFER(USBHID_N_TRANSFER)];
struct usbhid_xfer_ctx sc_xfer_ctx[POLL_XFER(USBHID_N_TRANSFER)];
static const struct usb_config usbhid_config[USBHID_N_TRANSFER] = {
for (n = 0; n != USBHID_N_TRANSFER; n++) {
for (n = 0; n != USBHID_N_TRANSFER; n++) {
usbd_transfer_unsetup(sc->sc_xfer, USBHID_N_TRANSFER);
sc->sc_xfer, POLL_XFER(USBHID_N_TRANSFER));
#define POLL_XFER(xfer) ((xfer) + USBHID_N_TRANSFER)