uhci-q.c

usb driver for 2.6.17

			(ret == -EREMOTEIO);
	return ret;
}

static inline int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb,
		struct uhci_qh *qh)
{
	int ret;

	/* Can't have low-speed bulk transfers */
	if (urb->dev->speed == USB_SPEED_LOW)
		return -EINVAL;

	qh->skel = uhci->skel_bulk_qh;
	ret = uhci_submit_common(uhci, urb, qh);
	if (ret == 0)
		uhci_inc_fsbr(uhci, urb);
	return ret;
}

static inline int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb,
		struct uhci_qh *qh)
{
	/* USB 1.1 interrupt transfers only involve one packet per interval.
	 * Drivers can submit URBs of any length, but longer ones will need
	 * multiple intervals to complete.
	 */
	qh->skel = uhci->skelqh[__interval_to_skel(urb->interval)];
	return uhci_submit_common(uhci, urb, qh);
}

/*
 * Isochronous transfers
 */
static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
		struct uhci_qh *qh)
{
	struct uhci_td *td = NULL;	/* Since urb->number_of_packets > 0 */
	int i, frame;
	unsigned long destination, status;
	struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;

	if (urb->number_of_packets > 900)	/* 900? Why? */
		return -EFBIG;

	status = TD_CTRL_ACTIVE | TD_CTRL_IOS;
	destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe);

	/* Figure out the starting frame number */
	if (urb->transfer_flags & URB_ISO_ASAP) {
		if (list_empty(&qh->queue)) {
			uhci_get_current_frame_number(uhci);
			urb->start_frame = (uhci->frame_number + 10);

		} else {		/* Go right after the last one */
			struct urb *last_urb;

			last_urb = list_entry(qh->queue.prev,
					struct urb_priv, node)->urb;
			urb->start_frame = (last_urb->start_frame +
					last_urb->number_of_packets *
					last_urb->interval);
		}
	} else {
		/* FIXME: Sanity check */
	}
	urb->start_frame &= (UHCI_NUMFRAMES - 1);

	for (i = 0; i < urb->number_of_packets; i++) {
		td = uhci_alloc_td(uhci);
		if (!td)
			return -ENOMEM;

		uhci_add_td_to_urb(urb, td);
		uhci_fill_td(td, status, destination |
				uhci_explen(urb->iso_frame_desc[i].length),
				urb->transfer_dma +
					urb->iso_frame_desc[i].offset);
	}

	/* Set the interrupt-on-completion flag on the last packet. */
	td->status |= __constant_cpu_to_le32(TD_CTRL_IOC);

	qh->skel = uhci->skel_iso_qh;

	/* Add the TDs to the frame list */
	frame = urb->start_frame;
	list_for_each_entry(td, &urbp->td_list, list) {
		uhci_insert_td_in_frame_list(uhci, td, frame);
		frame += urb->interval;
	}

	return 0;
}

static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
{
	struct uhci_td *td;
	struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
	int status;
	int i, ret = 0;

	urb->actual_length = urb->error_count = 0;

	i = 0;
	list_for_each_entry(td, &urbp->td_list, list) {
		int actlength;
		unsigned int ctrlstat = td_status(td);

		if (ctrlstat & TD_CTRL_ACTIVE)
			return -EINPROGRESS;

		actlength = uhci_actual_length(ctrlstat);
		urb->iso_frame_desc[i].actual_length = actlength;
		urb->actual_length += actlength;

		status = uhci_map_status(uhci_status_bits(ctrlstat),
				usb_pipeout(urb->pipe));
		urb->iso_frame_desc[i].status = status;
		if (status) {
			urb->error_count++;
			ret = status;
		}

		i++;
	}

	return ret;
}

static int uhci_urb_enqueue(struct usb_hcd *hcd,
		struct usb_host_endpoint *hep,
		struct urb *urb, gfp_t mem_flags)
{
	int ret;
	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
	unsigned long flags;
	struct urb_priv *urbp;
	struct uhci_qh *qh;
	int bustime;

	spin_lock_irqsave(&uhci->lock, flags);

	ret = urb->status;
	if (ret != -EINPROGRESS)		/* URB already unlinked! */
		goto done;

	ret = -ENOMEM;
	urbp = uhci_alloc_urb_priv(uhci, urb);
	if (!urbp)
		goto done;

	if (hep->hcpriv)
		qh = (struct uhci_qh *) hep->hcpriv;
	else {
		qh = uhci_alloc_qh(uhci, urb->dev, hep);
		if (!qh)
			goto err_no_qh;
	}
	urbp->qh = qh;

	switch (usb_pipetype(urb->pipe)) {
	case PIPE_CONTROL:
		ret = uhci_submit_control(uhci, urb, qh);
		break;
	case PIPE_BULK:
		ret = uhci_submit_bulk(uhci, urb, qh);
		break;
	case PIPE_INTERRUPT:
		if (list_empty(&qh->queue)) {
			bustime = usb_check_bandwidth(urb->dev, urb);
			if (bustime < 0)
				ret = bustime;
			else {
				ret = uhci_submit_interrupt(uhci, urb, qh);
				if (ret == 0)
					usb_claim_bandwidth(urb->dev, urb, bustime, 0);
			}
		} else {	/* inherit from parent */
			struct urb_priv *eurbp;

			eurbp = list_entry(qh->queue.prev, struct urb_priv,
					node);
			urb->bandwidth = eurbp->urb->bandwidth;
			ret = uhci_submit_interrupt(uhci, urb, qh);
		}
		break;
	case PIPE_ISOCHRONOUS:
		bustime = usb_check_bandwidth(urb->dev, urb);
		if (bustime < 0) {
			ret = bustime;
			break;
		}

		ret = uhci_submit_isochronous(uhci, urb, qh);
		if (ret == 0)
			usb_claim_bandwidth(urb->dev, urb, bustime, 1);
		break;
	}
	if (ret != 0)
		goto err_submit_failed;

	/* Add this URB to the QH */
	urbp->qh = qh;
	list_add_tail(&urbp->node, &qh->queue);

	/* If the new URB is the first and only one on this QH then either
	 * the QH is new and idle or else it's unlinked and waiting to
	 * become idle, so we can activate it right away. */
	if (qh->queue.next == &urbp->node)
		uhci_activate_qh(uhci, qh);
	goto done;

err_submit_failed:
	if (qh->state == QH_STATE_IDLE)
		uhci_make_qh_idle(uhci, qh);	/* Reclaim unused QH */

err_no_qh:
	uhci_free_urb_priv(uhci, urbp);

done:
	spin_unlock_irqrestore(&uhci->lock, flags);
	return ret;
}

static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb)
{
	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
	unsigned long flags;
	struct urb_priv *urbp;

	spin_lock_irqsave(&uhci->lock, flags);
	urbp = urb->hcpriv;
	if (!urbp)			/* URB was never linked! */
		goto done;

	/* Remove Isochronous TDs from the frame list ASAP */
	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
		uhci_unlink_isochronous_tds(uhci, urb);
	uhci_unlink_qh(uhci, urbp->qh);

done:
	spin_unlock_irqrestore(&uhci->lock, flags);
	return 0;
}

/*
 * Finish unlinking an URB and give it back
 */
static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh,
		struct urb *urb, struct pt_regs *regs)
__releases(uhci->lock)
__acquires(uhci->lock)
{
	struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;

	/* Isochronous TDs get unlinked directly from the frame list */
	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS)
		uhci_unlink_isochronous_tds(uhci, urb);

	/* If the URB isn't first on its queue, adjust the link pointer
	 * of the last TD in the previous URB. */
	else if (qh->queue.next != &urbp->node) {
		struct urb_priv *purbp;
		struct uhci_td *ptd, *ltd;

		purbp = list_entry(urbp->node.prev, struct urb_priv, node);
		ptd = list_entry(purbp->td_list.prev, struct uhci_td,
				list);
		ltd = list_entry(urbp->td_list.prev, struct uhci_td,
				list);
		ptd->link = ltd->link;
	}

	/* Take the URB off the QH's queue.  If the queue is now empty,
	 * this is a perfect time for a toggle fixup. */
	list_del_init(&urbp->node);
	if (list_empty(&qh->queue) && qh->needs_fixup) {
		usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
				usb_pipeout(urb->pipe), qh->initial_toggle);
		qh->needs_fixup = 0;
	}

	uhci_dec_fsbr(uhci, urb);	/* Safe since it checks */
	uhci_free_urb_priv(uhci, urbp);

	switch (usb_pipetype(urb->pipe)) {
	case PIPE_ISOCHRONOUS:
		/* Release bandwidth for Interrupt or Isoc. transfers */
		if (urb->bandwidth)
			usb_release_bandwidth(urb->dev, urb, 1);
		break;
	case PIPE_INTERRUPT:
		/* Release bandwidth for Interrupt or Isoc. transfers */
		/* Make sure we don't release if we have a queued URB */
		if (list_empty(&qh->queue) && urb->bandwidth)
			usb_release_bandwidth(urb->dev, urb, 0);
		else
			/* bandwidth was passed on to queued URB, */
			/* so don't let usb_unlink_urb() release it */
			urb->bandwidth = 0;
		break;
	}

	spin_unlock(&uhci->lock);
	usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb, regs);
	spin_lock(&uhci->lock);

	/* If the queue is now empty, we can unlink the QH and give up its
	 * reserved bandwidth. */
	if (list_empty(&qh->queue)) {
		uhci_unlink_qh(uhci, qh);

		/* Bandwidth stuff not yet implemented */
	}
}

/*
 * Scan the URBs in a QH's queue
 */
#define QH_FINISHED_UNLINKING(qh)			\
		(qh->state == QH_STATE_UNLINKING &&	\
		uhci->frame_number + uhci->is_stopped != qh->unlink_frame)

static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh,
		struct pt_regs *regs)
{
	struct urb_priv *urbp;
	struct urb *urb;
	int status;

	while (!list_empty(&qh->queue)) {
		urbp = list_entry(qh->queue.next, struct urb_priv, node);
		urb = urbp->urb;

		switch (usb_pipetype(urb->pipe)) {
		case PIPE_CONTROL:
			status = uhci_result_control(uhci, urb);
			break;
		case PIPE_ISOCHRONOUS:
			status = uhci_result_isochronous(uhci, urb);
			break;
		default:	/* PIPE_BULK or PIPE_INTERRUPT */
			status = uhci_result_common(uhci, urb);
			break;
		}
		if (status == -EINPROGRESS)
			break;

		spin_lock(&urb->lock);
		if (urb->status == -EINPROGRESS)	/* Not dequeued */
			urb->status = status;
		else
			status = -ECONNRESET;
		spin_unlock(&urb->lock);

		/* Dequeued but completed URBs can't be given back unless
		 * the QH is stopped or has finished unlinking. */
		if (status == -ECONNRESET &&
				!(qh->is_stopped || QH_FINISHED_UNLINKING(qh)))
			return;

		uhci_giveback_urb(uhci, qh, urb, regs);
		if (qh->is_stopped)
			break;
	}

	/* If the QH is neither stopped nor finished unlinking (normal case),
	 * our work here is done. */
 restart:
	if (!(qh->is_stopped || QH_FINISHED_UNLINKING(qh)))
		return;

	/* Otherwise give back each of the dequeued URBs */
	list_for_each_entry(urbp, &qh->queue, node) {
		urb = urbp->urb;
		if (urb->status != -EINPROGRESS) {
			uhci_save_toggle(qh, urb);
			uhci_giveback_urb(uhci, qh, urb, regs);
			goto restart;
		}
	}
	qh->is_stopped = 0;

	/* There are no more dequeued URBs.  If there are still URBs on the
	 * queue, the QH can now be re-activated. */
	if (!list_empty(&qh->queue)) {
		if (qh->needs_fixup)
			uhci_fixup_toggles(qh, 0);
		uhci_activate_qh(uhci, qh);
	}

	/* The queue is empty.  The QH can become idle if it is fully
	 * unlinked. */
	else if (QH_FINISHED_UNLINKING(qh))
		uhci_make_qh_idle(uhci, qh);
}

static void uhci_free_pending_tds(struct uhci_hcd *uhci)
{
	struct uhci_td *td, *tmp;

	list_for_each_entry_safe(td, tmp, &uhci->td_remove_list, remove_list) {
		list_del_init(&td->remove_list);

		uhci_free_td(uhci, td);
	}
}

/*
 * Process events in the schedule, but only in one thread at a time
 */
static void uhci_scan_schedule(struct uhci_hcd *uhci, struct pt_regs *regs)
{
	int i;
	struct uhci_qh *qh;

	/* Don't allow re-entrant calls */
	if (uhci->scan_in_progress) {
		uhci->need_rescan = 1;
		return;
	}
	uhci->scan_in_progress = 1;
 rescan:
	uhci->need_rescan = 0;

	uhci_clear_next_interrupt(uhci);
	uhci_get_current_frame_number(uhci);

	if (uhci->frame_number + uhci->is_stopped != uhci->td_remove_age)
		uhci_free_pending_tds(uhci);

	/* Go through all the QH queues and process the URBs in each one */
	for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
		uhci->next_qh = list_entry(uhci->skelqh[i]->node.next,
				struct uhci_qh, node);
		while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
			uhci->next_qh = list_entry(qh->node.next,
					struct uhci_qh, node);
			uhci_scan_qh(uhci, qh, regs);
		}
	}

	if (uhci->need_rescan)
		goto rescan;
	uhci->scan_in_progress = 0;

	/* If the controller is stopped, we can finish these off right now */
	if (uhci->is_stopped)
		uhci_free_pending_tds(uhci);

	if (list_empty(&uhci->td_remove_list) &&
			list_empty(&uhci->skel_unlink_qh->node))
		uhci_clear_next_interrupt(uhci);
	else
		uhci_set_next_interrupt(uhci);
}

static void check_fsbr(struct uhci_hcd *uhci)
{
	/* For now, don't scan URBs for FSBR timeouts.
	 * Add it back in later... */

	/* Really disable FSBR */
	if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
		uhci->fsbrtimeout = 0;
		uhci->skel_term_qh->link = UHCI_PTR_TERM;
	}
}