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Commit b951c6c7 authored by Douglas Anderson's avatar Douglas Anderson Committed by Felipe Balbi
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usb: dwc2: host: Reorder things in hcd_queue.c



This no-op change just reorders a few functions in hcd_queue.c in order
to prepare for future changes.  Motivations here:

The functions dwc2_hcd_qh_free() and dwc2_hcd_qh_create() are exported
functions.  They are not called within the file.  That means that they
should be near the bottom so that they can easily call static helpers.

The function dwc2_qh_init() is only called by dwc2_hcd_qh_create() and
should move near the bottom with it.

The only reason that the dwc2_unreserve_timer_fn() timer function (and
its subroutine dwc2_do_unreserve()) were so high in the file was that
they needed to be above dwc2_qh_init().  Now that dwc2_qh_init() has
been moved down it can be moved down a bit.  A later patch will split
the reserve code out of dwc2_schedule_periodic() and the reserve
function should be near the unreserve function.  The reserve function
needs to be below dwc2_find_uframe() since it calls that.

Acked-by: default avatarJohn Youn <johnyoun@synopsys.com>
Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Tested-by: default avatarHeiko Stuebner <heiko@sntech.de>
Tested-by: default avatarStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: default avatarFelipe Balbi <balbi@kernel.org>
parent ced9eee1
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+300 −300
Original line number Diff line number Diff line
@@ -56,295 +56,6 @@
/* Wait this long before releasing periodic reservation */
#define DWC2_UNRESERVE_DELAY (msecs_to_jiffies(5))

/**
 * dwc2_do_unreserve() - Actually release the periodic reservation
 *
 * This function actually releases the periodic bandwidth that was reserved
 * by the given qh.
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH for the periodic transfer.
 */
static void dwc2_do_unreserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
	assert_spin_locked(&hsotg->lock);

	WARN_ON(!qh->unreserve_pending);

	/* No more unreserve pending--we're doing it */
	qh->unreserve_pending = false;

	if (WARN_ON(!list_empty(&qh->qh_list_entry)))
		list_del_init(&qh->qh_list_entry);

	/* Update claimed usecs per (micro)frame */
	hsotg->periodic_usecs -= qh->host_us;

	if (hsotg->core_params->uframe_sched > 0) {
		int i;

		for (i = 0; i < 8; i++) {
			hsotg->frame_usecs[i] += qh->frame_usecs[i];
			qh->frame_usecs[i] = 0;
		}
	} else {
		/* Release periodic channel reservation */
		hsotg->periodic_channels--;
	}
}

/**
 * dwc2_unreserve_timer_fn() - Timer function to release periodic reservation
 *
 * According to the kernel doc for usb_submit_urb() (specifically the part about
 * "Reserved Bandwidth Transfers"), we need to keep a reservation active as
 * long as a device driver keeps submitting.  Since we're using HCD_BH to give
 * back the URB we need to give the driver a little bit of time before we
 * release the reservation.  This worker is called after the appropriate
 * delay.
 *
 * @work: Pointer to a qh unreserve_work.
 */
static void dwc2_unreserve_timer_fn(unsigned long data)
{
	struct dwc2_qh *qh = (struct dwc2_qh *)data;
	struct dwc2_hsotg *hsotg = qh->hsotg;
	unsigned long flags;

	/*
	 * Wait for the lock, or for us to be scheduled again.  We
	 * could be scheduled again if:
	 * - We started executing but didn't get the lock yet.
	 * - A new reservation came in, but cancel didn't take effect
	 *   because we already started executing.
	 * - The timer has been kicked again.
	 * In that case cancel and wait for the next call.
	 */
	while (!spin_trylock_irqsave(&hsotg->lock, flags)) {
		if (timer_pending(&qh->unreserve_timer))
			return;
	}

	/*
	 * Might be no more unreserve pending if:
	 * - We started executing but didn't get the lock yet.
	 * - A new reservation came in, but cancel didn't take effect
	 *   because we already started executing.
	 *
	 * We can't put this in the loop above because unreserve_pending needs
	 * to be accessed under lock, so we can only check it once we got the
	 * lock.
	 */
	if (qh->unreserve_pending)
		dwc2_do_unreserve(hsotg, qh);

	spin_unlock_irqrestore(&hsotg->lock, flags);
}

/**
 * dwc2_qh_init() - Initializes a QH structure
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    The QH to init
 * @urb:   Holds the information about the device/endpoint needed to initialize
 *         the QH
 */
#define SCHEDULE_SLOP 10
static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
			 struct dwc2_hcd_urb *urb)
{
	int dev_speed, hub_addr, hub_port;
	char *speed, *type;

	dev_vdbg(hsotg->dev, "%s()\n", __func__);

	/* Initialize QH */
	qh->hsotg = hsotg;
	setup_timer(&qh->unreserve_timer, dwc2_unreserve_timer_fn,
		    (unsigned long)qh);
	qh->ep_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
	qh->ep_is_in = dwc2_hcd_is_pipe_in(&urb->pipe_info) ? 1 : 0;

	qh->data_toggle = DWC2_HC_PID_DATA0;
	qh->maxp = dwc2_hcd_get_mps(&urb->pipe_info);
	INIT_LIST_HEAD(&qh->qtd_list);
	INIT_LIST_HEAD(&qh->qh_list_entry);

	/* FS/LS Endpoint on HS Hub, NOT virtual root hub */
	dev_speed = dwc2_host_get_speed(hsotg, urb->priv);

	dwc2_host_hub_info(hsotg, urb->priv, &hub_addr, &hub_port);

	if ((dev_speed == USB_SPEED_LOW || dev_speed == USB_SPEED_FULL) &&
	    hub_addr != 0 && hub_addr != 1) {
		dev_vdbg(hsotg->dev,
			 "QH init: EP %d: TT found at hub addr %d, for port %d\n",
			 dwc2_hcd_get_ep_num(&urb->pipe_info), hub_addr,
			 hub_port);
		qh->do_split = 1;
	}

	if (qh->ep_type == USB_ENDPOINT_XFER_INT ||
	    qh->ep_type == USB_ENDPOINT_XFER_ISOC) {
		/* Compute scheduling parameters once and save them */
		u32 hprt, prtspd;

		/* Todo: Account for split transfers in the bus time */
		int bytecount =
			dwc2_hb_mult(qh->maxp) * dwc2_max_packet(qh->maxp);

		qh->host_us = NS_TO_US(usb_calc_bus_time(qh->do_split ?
			      USB_SPEED_HIGH : dev_speed, qh->ep_is_in,
			      qh->ep_type == USB_ENDPOINT_XFER_ISOC,
			      bytecount));

		/* Ensure frame_number corresponds to the reality */
		hsotg->frame_number = dwc2_hcd_get_frame_number(hsotg);
		/* Start in a slightly future (micro)frame */
		qh->next_active_frame = dwc2_frame_num_inc(hsotg->frame_number,
						     SCHEDULE_SLOP);
		qh->host_interval = urb->interval;
		dwc2_sch_dbg(hsotg, "QH=%p init nxt=%04x, fn=%04x, int=%#x\n",
			     qh, qh->next_active_frame, hsotg->frame_number,
			     qh->host_interval);
#if 0
		/* Increase interrupt polling rate for debugging */
		if (qh->ep_type == USB_ENDPOINT_XFER_INT)
			qh->host_interval = 8;
#endif
		hprt = dwc2_readl(hsotg->regs + HPRT0);
		prtspd = (hprt & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
		if (prtspd == HPRT0_SPD_HIGH_SPEED &&
		    (dev_speed == USB_SPEED_LOW ||
		     dev_speed == USB_SPEED_FULL)) {
			qh->host_interval *= 8;
			qh->next_active_frame |= 0x7;
			qh->start_split_frame = qh->next_active_frame;
			dwc2_sch_dbg(hsotg,
				     "QH=%p init*8 nxt=%04x, fn=%04x, int=%#x\n",
				     qh, qh->next_active_frame,
				     hsotg->frame_number, qh->host_interval);

		}
		dev_dbg(hsotg->dev, "interval=%d\n", qh->host_interval);
	}

	dev_vdbg(hsotg->dev, "DWC OTG HCD QH Initialized\n");
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - qh = %p\n", qh);
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Device Address = %d\n",
		 dwc2_hcd_get_dev_addr(&urb->pipe_info));
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Endpoint %d, %s\n",
		 dwc2_hcd_get_ep_num(&urb->pipe_info),
		 dwc2_hcd_is_pipe_in(&urb->pipe_info) ? "IN" : "OUT");

	qh->dev_speed = dev_speed;

	switch (dev_speed) {
	case USB_SPEED_LOW:
		speed = "low";
		break;
	case USB_SPEED_FULL:
		speed = "full";
		break;
	case USB_SPEED_HIGH:
		speed = "high";
		break;
	default:
		speed = "?";
		break;
	}
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Speed = %s\n", speed);

	switch (qh->ep_type) {
	case USB_ENDPOINT_XFER_ISOC:
		type = "isochronous";
		break;
	case USB_ENDPOINT_XFER_INT:
		type = "interrupt";
		break;
	case USB_ENDPOINT_XFER_CONTROL:
		type = "control";
		break;
	case USB_ENDPOINT_XFER_BULK:
		type = "bulk";
		break;
	default:
		type = "?";
		break;
	}

	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Type = %s\n", type);

	if (qh->ep_type == USB_ENDPOINT_XFER_INT) {
		dev_vdbg(hsotg->dev, "DWC OTG HCD QH - usecs = %d\n",
			 qh->host_us);
		dev_vdbg(hsotg->dev, "DWC OTG HCD QH - interval = %d\n",
			 qh->host_interval);
	}
}

/**
 * dwc2_hcd_qh_create() - Allocates and initializes a QH
 *
 * @hsotg:        The HCD state structure for the DWC OTG controller
 * @urb:          Holds the information about the device/endpoint needed
 *                to initialize the QH
 * @atomic_alloc: Flag to do atomic allocation if needed
 *
 * Return: Pointer to the newly allocated QH, or NULL on error
 */
struct dwc2_qh *dwc2_hcd_qh_create(struct dwc2_hsotg *hsotg,
					  struct dwc2_hcd_urb *urb,
					  gfp_t mem_flags)
{
	struct dwc2_qh *qh;

	if (!urb->priv)
		return NULL;

	/* Allocate memory */
	qh = kzalloc(sizeof(*qh), mem_flags);
	if (!qh)
		return NULL;

	dwc2_qh_init(hsotg, qh, urb);

	if (hsotg->core_params->dma_desc_enable > 0 &&
	    dwc2_hcd_qh_init_ddma(hsotg, qh, mem_flags) < 0) {
		dwc2_hcd_qh_free(hsotg, qh);
		return NULL;
	}

	return qh;
}

/**
 * dwc2_hcd_qh_free() - Frees the QH
 *
 * @hsotg: HCD instance
 * @qh:    The QH to free
 *
 * QH should already be removed from the list. QTD list should already be empty
 * if called from URB Dequeue.
 *
 * Must NOT be called with interrupt disabled or spinlock held
 */
void dwc2_hcd_qh_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
	/* Make sure any unreserve work is finished. */
	if (del_timer_sync(&qh->unreserve_timer)) {
		unsigned long flags;

		spin_lock_irqsave(&hsotg->lock, flags);
		dwc2_do_unreserve(hsotg, qh);
		spin_unlock_irqrestore(&hsotg->lock, flags);
	}

	if (qh->desc_list)
		dwc2_hcd_qh_free_ddma(hsotg, qh);
	kfree(qh);
}

/**
 * dwc2_periodic_channel_available() - Checks that a channel is available for a
 * periodic transfer
@@ -513,24 +224,109 @@ static int dwc2_find_multi_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
				continue;
		}
	}
	return -ENOSPC;
	return -ENOSPC;
}

static int dwc2_find_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
	int ret;

	if (qh->dev_speed == USB_SPEED_HIGH) {
		/* if this is a hs transaction we need a full frame */
		ret = dwc2_find_single_uframe(hsotg, qh);
	} else {
		/*
		 * if this is a fs transaction we may need a sequence
		 * of frames
		 */
		ret = dwc2_find_multi_uframe(hsotg, qh);
	}
	return ret;
}

/**
 * dwc2_do_unreserve() - Actually release the periodic reservation
 *
 * This function actually releases the periodic bandwidth that was reserved
 * by the given qh.
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH for the periodic transfer.
 */
static void dwc2_do_unreserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
	assert_spin_locked(&hsotg->lock);

	WARN_ON(!qh->unreserve_pending);

	/* No more unreserve pending--we're doing it */
	qh->unreserve_pending = false;

	if (WARN_ON(!list_empty(&qh->qh_list_entry)))
		list_del_init(&qh->qh_list_entry);

	/* Update claimed usecs per (micro)frame */
	hsotg->periodic_usecs -= qh->host_us;

	if (hsotg->core_params->uframe_sched > 0) {
		int i;

		for (i = 0; i < 8; i++) {
			hsotg->frame_usecs[i] += qh->frame_usecs[i];
			qh->frame_usecs[i] = 0;
		}
	} else {
		/* Release periodic channel reservation */
		hsotg->periodic_channels--;
	}
}

static int dwc2_find_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
/**
 * dwc2_unreserve_timer_fn() - Timer function to release periodic reservation
 *
 * According to the kernel doc for usb_submit_urb() (specifically the part about
 * "Reserved Bandwidth Transfers"), we need to keep a reservation active as
 * long as a device driver keeps submitting.  Since we're using HCD_BH to give
 * back the URB we need to give the driver a little bit of time before we
 * release the reservation.  This worker is called after the appropriate
 * delay.
 *
 * @work: Pointer to a qh unreserve_work.
 */
static void dwc2_unreserve_timer_fn(unsigned long data)
{
	int ret;
	struct dwc2_qh *qh = (struct dwc2_qh *)data;
	struct dwc2_hsotg *hsotg = qh->hsotg;
	unsigned long flags;

	if (qh->dev_speed == USB_SPEED_HIGH) {
		/* if this is a hs transaction we need a full frame */
		ret = dwc2_find_single_uframe(hsotg, qh);
	} else {
	/*
		 * if this is a fs transaction we may need a sequence
		 * of frames
	 * Wait for the lock, or for us to be scheduled again.  We
	 * could be scheduled again if:
	 * - We started executing but didn't get the lock yet.
	 * - A new reservation came in, but cancel didn't take effect
	 *   because we already started executing.
	 * - The timer has been kicked again.
	 * In that case cancel and wait for the next call.
	 */
		ret = dwc2_find_multi_uframe(hsotg, qh);
	while (!spin_trylock_irqsave(&hsotg->lock, flags)) {
		if (timer_pending(&qh->unreserve_timer))
			return;
	}
	return ret;

	/*
	 * Might be no more unreserve pending if:
	 * - We started executing but didn't get the lock yet.
	 * - A new reservation came in, but cancel didn't take effect
	 *   because we already started executing.
	 *
	 * We can't put this in the loop above because unreserve_pending needs
	 * to be accessed under lock, so we can only check it once we got the
	 * lock.
	 */
	if (qh->unreserve_pending)
		dwc2_do_unreserve(hsotg, qh);

	spin_unlock_irqrestore(&hsotg->lock, flags);
}

/**
@@ -694,6 +490,210 @@ static void dwc2_deschedule_periodic(struct dwc2_hsotg *hsotg,
	list_del_init(&qh->qh_list_entry);
}

/**
 * dwc2_qh_init() - Initializes a QH structure
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    The QH to init
 * @urb:   Holds the information about the device/endpoint needed to initialize
 *         the QH
 */
#define SCHEDULE_SLOP 10
static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
			 struct dwc2_hcd_urb *urb)
{
	int dev_speed, hub_addr, hub_port;
	char *speed, *type;

	dev_vdbg(hsotg->dev, "%s()\n", __func__);

	/* Initialize QH */
	qh->hsotg = hsotg;
	setup_timer(&qh->unreserve_timer, dwc2_unreserve_timer_fn,
		    (unsigned long)qh);
	qh->ep_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
	qh->ep_is_in = dwc2_hcd_is_pipe_in(&urb->pipe_info) ? 1 : 0;

	qh->data_toggle = DWC2_HC_PID_DATA0;
	qh->maxp = dwc2_hcd_get_mps(&urb->pipe_info);
	INIT_LIST_HEAD(&qh->qtd_list);
	INIT_LIST_HEAD(&qh->qh_list_entry);

	/* FS/LS Endpoint on HS Hub, NOT virtual root hub */
	dev_speed = dwc2_host_get_speed(hsotg, urb->priv);

	dwc2_host_hub_info(hsotg, urb->priv, &hub_addr, &hub_port);

	if ((dev_speed == USB_SPEED_LOW || dev_speed == USB_SPEED_FULL) &&
	    hub_addr != 0 && hub_addr != 1) {
		dev_vdbg(hsotg->dev,
			 "QH init: EP %d: TT found at hub addr %d, for port %d\n",
			 dwc2_hcd_get_ep_num(&urb->pipe_info), hub_addr,
			 hub_port);
		qh->do_split = 1;
	}

	if (qh->ep_type == USB_ENDPOINT_XFER_INT ||
	    qh->ep_type == USB_ENDPOINT_XFER_ISOC) {
		/* Compute scheduling parameters once and save them */
		u32 hprt, prtspd;

		/* Todo: Account for split transfers in the bus time */
		int bytecount =
			dwc2_hb_mult(qh->maxp) * dwc2_max_packet(qh->maxp);

		qh->host_us = NS_TO_US(usb_calc_bus_time(qh->do_split ?
			      USB_SPEED_HIGH : dev_speed, qh->ep_is_in,
			      qh->ep_type == USB_ENDPOINT_XFER_ISOC,
			      bytecount));

		/* Ensure frame_number corresponds to the reality */
		hsotg->frame_number = dwc2_hcd_get_frame_number(hsotg);
		/* Start in a slightly future (micro)frame */
		qh->next_active_frame = dwc2_frame_num_inc(hsotg->frame_number,
						     SCHEDULE_SLOP);
		qh->host_interval = urb->interval;
		dwc2_sch_dbg(hsotg, "QH=%p init nxt=%04x, fn=%04x, int=%#x\n",
			     qh, qh->next_active_frame, hsotg->frame_number,
			     qh->host_interval);
#if 0
		/* Increase interrupt polling rate for debugging */
		if (qh->ep_type == USB_ENDPOINT_XFER_INT)
			qh->host_interval = 8;
#endif
		hprt = dwc2_readl(hsotg->regs + HPRT0);
		prtspd = (hprt & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
		if (prtspd == HPRT0_SPD_HIGH_SPEED &&
		    (dev_speed == USB_SPEED_LOW ||
		     dev_speed == USB_SPEED_FULL)) {
			qh->host_interval *= 8;
			qh->next_active_frame |= 0x7;
			qh->start_split_frame = qh->next_active_frame;
			dwc2_sch_dbg(hsotg,
				     "QH=%p init*8 nxt=%04x, fn=%04x, int=%#x\n",
				     qh, qh->next_active_frame,
				     hsotg->frame_number, qh->host_interval);

		}
		dev_dbg(hsotg->dev, "interval=%d\n", qh->host_interval);
	}

	dev_vdbg(hsotg->dev, "DWC OTG HCD QH Initialized\n");
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - qh = %p\n", qh);
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Device Address = %d\n",
		 dwc2_hcd_get_dev_addr(&urb->pipe_info));
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Endpoint %d, %s\n",
		 dwc2_hcd_get_ep_num(&urb->pipe_info),
		 dwc2_hcd_is_pipe_in(&urb->pipe_info) ? "IN" : "OUT");

	qh->dev_speed = dev_speed;

	switch (dev_speed) {
	case USB_SPEED_LOW:
		speed = "low";
		break;
	case USB_SPEED_FULL:
		speed = "full";
		break;
	case USB_SPEED_HIGH:
		speed = "high";
		break;
	default:
		speed = "?";
		break;
	}
	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Speed = %s\n", speed);

	switch (qh->ep_type) {
	case USB_ENDPOINT_XFER_ISOC:
		type = "isochronous";
		break;
	case USB_ENDPOINT_XFER_INT:
		type = "interrupt";
		break;
	case USB_ENDPOINT_XFER_CONTROL:
		type = "control";
		break;
	case USB_ENDPOINT_XFER_BULK:
		type = "bulk";
		break;
	default:
		type = "?";
		break;
	}

	dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Type = %s\n", type);

	if (qh->ep_type == USB_ENDPOINT_XFER_INT) {
		dev_vdbg(hsotg->dev, "DWC OTG HCD QH - usecs = %d\n",
			 qh->host_us);
		dev_vdbg(hsotg->dev, "DWC OTG HCD QH - interval = %d\n",
			 qh->host_interval);
	}
}

/**
 * dwc2_hcd_qh_create() - Allocates and initializes a QH
 *
 * @hsotg:        The HCD state structure for the DWC OTG controller
 * @urb:          Holds the information about the device/endpoint needed
 *                to initialize the QH
 * @atomic_alloc: Flag to do atomic allocation if needed
 *
 * Return: Pointer to the newly allocated QH, or NULL on error
 */
struct dwc2_qh *dwc2_hcd_qh_create(struct dwc2_hsotg *hsotg,
					  struct dwc2_hcd_urb *urb,
					  gfp_t mem_flags)
{
	struct dwc2_qh *qh;

	if (!urb->priv)
		return NULL;

	/* Allocate memory */
	qh = kzalloc(sizeof(*qh), mem_flags);
	if (!qh)
		return NULL;

	dwc2_qh_init(hsotg, qh, urb);

	if (hsotg->core_params->dma_desc_enable > 0 &&
	    dwc2_hcd_qh_init_ddma(hsotg, qh, mem_flags) < 0) {
		dwc2_hcd_qh_free(hsotg, qh);
		return NULL;
	}

	return qh;
}

/**
 * dwc2_hcd_qh_free() - Frees the QH
 *
 * @hsotg: HCD instance
 * @qh:    The QH to free
 *
 * QH should already be removed from the list. QTD list should already be empty
 * if called from URB Dequeue.
 *
 * Must NOT be called with interrupt disabled or spinlock held
 */
void dwc2_hcd_qh_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
	/* Make sure any unreserve work is finished. */
	if (del_timer_sync(&qh->unreserve_timer)) {
		unsigned long flags;

		spin_lock_irqsave(&hsotg->lock, flags);
		dwc2_do_unreserve(hsotg, qh);
		spin_unlock_irqrestore(&hsotg->lock, flags);
	}

	if (qh->desc_list)
		dwc2_hcd_qh_free_ddma(hsotg, qh);
	kfree(qh);
}

/**
 * dwc2_hcd_qh_add() - Adds a QH to either the non periodic or periodic
 * schedule if it is not already in the schedule. If the QH is already in