+#define STACKTDS 4
+#define TDALIGN 16
+
+int
+uhci_send_bulk(struct usb_pipe *p, int dir, void *data, int datasize)
+{
+ if (! CONFIG_USB_UHCI)
+ return -1;
+ struct uhci_pipe *pipe = container_of(p, struct uhci_pipe, pipe);
+ dprintf(7, "uhci_send_bulk qh=%p dir=%d data=%p size=%d\n"
+ , &pipe->qh, dir, data, datasize);
+ int maxpacket = GET_FLATPTR(pipe->pipe.maxpacket);
+ int lowspeed = GET_FLATPTR(pipe->pipe.speed);
+ int devaddr = (GET_FLATPTR(pipe->pipe.devaddr)
+ | (GET_FLATPTR(pipe->pipe.ep) << 7));
+ int toggle = GET_FLATPTR(pipe->toggle) ? TD_TOKEN_TOGGLE : 0;
+
+ // Allocate 4 tds on stack (16byte aligned)
+ u8 tdsbuf[sizeof(struct uhci_td) * STACKTDS + TDALIGN - 1];
+ struct uhci_td *tds = (void*)ALIGN((u32)tdsbuf, TDALIGN);
+ memset(tds, 0, sizeof(*tds) * STACKTDS);
+
+ // Enable tds
+ barrier();
+ SET_FLATPTR(pipe->qh.element, (u32)MAKE_FLATPTR(GET_SEG(SS), tds));
+
+ int tdpos = 0;
+ while (datasize) {
+ struct uhci_td *td = &tds[tdpos++ % STACKTDS];
+ int ret = wait_td(td);
+ if (ret)
+ goto fail;
+
+ int transfer = datasize;
+ if (transfer > maxpacket)
+ transfer = maxpacket;
+ struct uhci_td *nexttd_fl = MAKE_FLATPTR(GET_SEG(SS)
+ , &tds[tdpos % STACKTDS]);
+ td->link = (transfer==datasize ? UHCI_PTR_TERM : (u32)nexttd_fl);
+ td->token = (uhci_explen(transfer) | toggle
+ | (devaddr << TD_TOKEN_DEVADDR_SHIFT)
+ | (dir ? USB_PID_IN : USB_PID_OUT));
+ td->buffer = data;
+ barrier();
+ td->status = (uhci_maxerr(3) | (lowspeed ? TD_CTRL_LS : 0)
+ | TD_CTRL_ACTIVE);
+ toggle ^= TD_TOKEN_TOGGLE;
+
+ data += transfer;
+ datasize -= transfer;
+ }
+ SET_FLATPTR(pipe->toggle, !!toggle);
+ return wait_pipe(pipe, 5000);
+fail:
+ dprintf(1, "uhci_send_bulk failed\n");
+ SET_FLATPTR(pipe->qh.element, UHCI_PTR_TERM);
+ uhci_waittick(GET_FLATPTR(pipe->iobase));
+ return -1;
+}
+