patch-2.4.21 linux-2.4.21/drivers/usb/hcd/ehci-q.c

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diff -urN linux-2.4.20/drivers/usb/hcd/ehci-q.c linux-2.4.21/drivers/usb/hcd/ehci-q.c
@@ -1,1004 +0,0 @@
-/*
- * Copyright (c) 2001-2002 by David Brownell
- * 
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-/* this file is part of ehci-hcd.c */
-
-/*-------------------------------------------------------------------------*/
-
-/*
- * EHCI hardware queue manipulation ... the core.  QH/QTD manipulation.
- *
- * Control, bulk, and interrupt traffic all use "qh" lists.  They list "qtd"
- * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned
- * buffers needed for the larger number).  We use one QH per endpoint, queue
- * multiple (bulk or control) urbs per endpoint.  URBs may need several qtds.
- * A scheduled interrupt qh always (for now) has one qtd, one urb.
- *
- * ISO traffic uses "ISO TD" (itd, and sitd) records, and (along with
- * interrupts) needs careful scheduling.  Performance improvements can be
- * an ongoing challenge.  That's in "ehci-sched.c".
- * 
- * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs,
- * or otherwise through transaction translators (TTs) in USB 2.0 hubs using
- * (b) special fields in qh entries or (c) split iso entries.  TTs will
- * buffer low/full speed data so the host collects it at high speed.
- */
-
-/*-------------------------------------------------------------------------*/
-
-/* fill a qtd, returning how much of the buffer we were able to queue up */
-
-static int
-qtd_fill (struct ehci_qtd *qtd, dma_addr_t buf, size_t len, int token)
-{
-	int	i, count;
-
-	/* one buffer entry per 4K ... first might be short or unaligned */
-	qtd->hw_buf [0] = cpu_to_le32 (buf);
-	count = 0x1000 - (buf & 0x0fff);	/* rest of that page */
-	if (likely (len < count))		/* ... iff needed */
-		count = len;
-	else {
-		buf +=  0x1000;
-		buf &= ~0x0fff;
-
-		/* per-qtd limit: from 16K to 20K (best alignment) */
-		for (i = 1; count < len && i < 5; i++) {
-			u64	addr = buf;
-			qtd->hw_buf [i] = cpu_to_le32 ((u32)addr);
-			qtd->hw_buf_hi [i] = cpu_to_le32 ((u32)(addr >> 32));
-			buf += 0x1000;
-			if ((count + 0x1000) < len)
-				count += 0x1000;
-			else
-				count = len;
-		}
-	}
-	qtd->hw_token = cpu_to_le32 ((count << 16) | token);
-	qtd->length = count;
-
-#if 0
-	vdbg ("  qtd_fill %p, token %8x bytes %d dma %x",
-		qtd, le32_to_cpu (qtd->hw_token), count, qtd->hw_buf [0]);
-#endif
-
-	return count;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/* update halted (but potentially linked) qh */
-
-static inline void qh_update (struct ehci_qh *qh, struct ehci_qtd *qtd)
-{
-	qh->hw_current = 0;
-	qh->hw_qtd_next = QTD_NEXT (qtd->qtd_dma);
-	qh->hw_alt_next = EHCI_LIST_END;
-
-	/* HC must see latest qtd and qh data before we clear ACTIVE+HALT */
-	wmb ();
-	qh->hw_token &= __constant_cpu_to_le32 (QTD_TOGGLE | QTD_STS_PING);
-}
-
-/*-------------------------------------------------------------------------*/
-
-static inline void qtd_copy_status (struct urb *urb, size_t length, u32 token)
-{
-	/* count IN/OUT bytes, not SETUP (even short packets) */
-	if (likely (QTD_PID (token) != 2))
-		urb->actual_length += length - QTD_LENGTH (token);
-
-	/* don't modify error codes */
-	if (unlikely (urb->status == -EINPROGRESS && (token & QTD_STS_HALT))) {
-		if (token & QTD_STS_BABBLE) {
-			/* FIXME "must" disable babbling device's port too */
-			urb->status = -EOVERFLOW;
-		} else if (token & QTD_STS_MMF) {
-			/* fs/ls interrupt xfer missed the complete-split */
-			urb->status = -EPROTO;
-		} else if (token & QTD_STS_DBE) {
-			urb->status = (QTD_PID (token) == 1) /* IN ? */
-				? -ENOSR  /* hc couldn't read data */
-				: -ECOMM; /* hc couldn't write data */
-		} else if (token & QTD_STS_XACT) {
-			/* timeout, bad crc, wrong PID, etc; retried */
-			if (QTD_CERR (token))
-				urb->status = -EPIPE;
-			else {
-				dbg ("3strikes");
-				urb->status = -EPROTO;
-			}
-		/* CERR nonzero + no errors + halt --> stall */
-		} else if (QTD_CERR (token))
-			urb->status = -EPIPE;
-		else	/* unknown */
-			urb->status = -EPROTO;
-
-		dbg ("ep %d-%s qtd token %08x --> status %d",
-			/* devpath */
-			usb_pipeendpoint (urb->pipe),
-			usb_pipein (urb->pipe) ? "in" : "out",
-			token, urb->status);
-
-		/* stall indicates some recovery action is needed */
-		if (urb->status == -EPIPE) {
-			int	pipe = urb->pipe;
-
-			if (!usb_pipecontrol (pipe))
-				usb_endpoint_halt (urb->dev,
-					usb_pipeendpoint (pipe),
-					usb_pipeout (pipe));
-			if (urb->dev->tt && !usb_pipeint (pipe)) {
-err ("must CLEAR_TT_BUFFER, hub port %d%s addr %d ep %d",
-    urb->dev->ttport, /* devpath */
-    urb->dev->tt->multi ? "" : " (all-ports TT)",
-    urb->dev->devnum, usb_pipeendpoint (urb->pipe));
-				// FIXME something (khubd?) should make the hub
-				// CLEAR_TT_BUFFER ASAP, it's blocking other
-				// fs/ls requests... hub_tt_clear_buffer() ?
-			}
-		}
-	}
-}
-
-static void ehci_urb_complete (
-	struct ehci_hcd		*ehci,
-	dma_addr_t		addr,
-	struct urb		*urb
-) {
-	if (urb->transfer_buffer_length && usb_pipein (urb->pipe))
-		pci_dma_sync_single (ehci->hcd.pdev, addr,
-			urb->transfer_buffer_length,
-			PCI_DMA_FROMDEVICE);
-
-	/* cleanse status if we saw no error */
-	if (likely (urb->status == -EINPROGRESS)) {
-		if (urb->actual_length != urb->transfer_buffer_length
-				&& (urb->transfer_flags & USB_DISABLE_SPD))
-			urb->status = -EREMOTEIO;
-		else
-			urb->status = 0;
-	}
-
-	/* only report unlinks once */
-	if (likely (urb->status != -ENOENT && urb->status != -ENOTCONN))
-		urb->complete (urb);
-}
-
-/* urb->lock ignored from here on (hcd is done with urb) */
-
-static void ehci_urb_done (
-	struct ehci_hcd		*ehci,
-	dma_addr_t		addr,
-	struct urb		*urb
-) {
-	if (urb->transfer_buffer_length)
-		pci_unmap_single (ehci->hcd.pdev,
-			addr,
-			urb->transfer_buffer_length,
-			usb_pipein (urb->pipe)
-			    ? PCI_DMA_FROMDEVICE
-			    : PCI_DMA_TODEVICE);
-	if (likely (urb->hcpriv != 0)) {
-		qh_put (ehci, (struct ehci_qh *) urb->hcpriv);
-		urb->hcpriv = 0;
-	}
-
-	if (likely (urb->status == -EINPROGRESS)) {
-		if (urb->actual_length != urb->transfer_buffer_length
-				&& (urb->transfer_flags & USB_DISABLE_SPD))
-			urb->status = -EREMOTEIO;
-		else
-			urb->status = 0;
-	}
-
-	/* hand off urb ownership */
-	usb_hcd_giveback_urb (&ehci->hcd, urb);
-}
-
-
-/*
- * Process completed qtds for a qh, issuing completions if needed.
- * When freeing:  frees qtds, unmaps buf, returns URB to driver.
- * When not freeing (queued periodic qh):  retain qtds, mapping, and urb.
- * Races up to qh->hw_current; returns number of urb completions.
- */
-static int
-qh_completions (
-	struct ehci_hcd		*ehci,
-	struct ehci_qh		*qh,
-	int			freeing
-) {
-	struct ehci_qtd		*qtd, *last;
-	struct list_head	*next, *qtd_list = &qh->qtd_list;
-	int			unlink = 0, halted = 0;
-	unsigned long		flags;
-	int			retval = 0;
-
-	spin_lock_irqsave (&ehci->lock, flags);
-	if (unlikely (list_empty (qtd_list))) {
-		spin_unlock_irqrestore (&ehci->lock, flags);
-		return retval;
-	}
-
-	/* scan QTDs till end of list, or we reach an active one */
-	for (qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list),
-			    	last = 0, next = 0;
-			next != qtd_list;
-			last = qtd, qtd = list_entry (next,
-						struct ehci_qtd, qtd_list)) {
-		struct urb	*urb = qtd->urb;
-		u32		token = 0;
-
-		/* clean up any state from previous QTD ...*/
-		if (last) {
-			if (likely (last->urb != urb)) {
-				/* complete() can reenter this HCD */
-				spin_unlock_irqrestore (&ehci->lock, flags);
-				if (likely (freeing != 0))
-					ehci_urb_done (ehci, last->buf_dma,
-						last->urb);
-				else
-					ehci_urb_complete (ehci, last->buf_dma,
-						last->urb);
-				spin_lock_irqsave (&ehci->lock, flags);
-				retval++;
-			}
-
-			/* qh overlays can have HC's old cached copies of
-			 * next qtd ptrs, if an URB was queued afterwards.
-			 */
-			if (cpu_to_le32 (last->qtd_dma) == qh->hw_current
-					&& last->hw_next != qh->hw_qtd_next) {
-				qh->hw_alt_next = last->hw_alt_next;
-				qh->hw_qtd_next = last->hw_next;
-			}
-
-			if (likely (freeing != 0))
-				ehci_qtd_free (ehci, last);
-			last = 0;
-		}
-		next = qtd->qtd_list.next;
-
-		/* QTDs at tail may be active if QH+HC are running,
-		 * or when unlinking some urbs queued to this QH
-		 */
-		token = le32_to_cpu (qtd->hw_token);
-		halted = halted
-			|| (__constant_cpu_to_le32 (QTD_STS_HALT)
-				& qh->hw_token) != 0
-			|| (ehci->hcd.state == USB_STATE_HALT)
-			|| (qh->qh_state == QH_STATE_IDLE);
-
-		/* fault: unlink the rest, since this qtd saw an error? */
-		if (unlikely ((token & QTD_STS_HALT) != 0)) {
-			freeing = unlink = 1;
-			/* status copied below */
-
-		/* QH halts only because of fault (above) or unlink (here). */
-		} else if (unlikely (halted != 0)) {
-
-			/* unlinking everything because of HC shutdown? */
-			if (ehci->hcd.state == USB_STATE_HALT) {
-				freeing = unlink = 1;
-
-			/* explicit unlink, maybe starting here? */
-			} else if (qh->qh_state == QH_STATE_IDLE
-					&& (urb->status == -ECONNRESET
-						|| urb->status == -ENOENT)) {
-				freeing = unlink = 1;
-
-			/* QH halted to unlink urbs _after_ this?  */
-			} else if (!unlink && (token & QTD_STS_ACTIVE) != 0) {
-				qtd = 0;
-				continue;
-			}
-
-			/* unlink the rest?  once we start unlinking, after
-			 * a fault or explicit unlink, we unlink all later
-			 * urbs.  usb spec requires that.
-			 */
-			if (unlink && urb->status == -EINPROGRESS)
-				urb->status = -ECONNRESET;
-
-		/* Else QH is active, so we must not modify QTDs
-		 * that HC may be working on.  No more qtds to check.
-		 */
-		} else if (unlikely ((token & QTD_STS_ACTIVE) != 0)) {
-			next = qtd_list;
-			qtd = 0;
-			continue;
-		}
-
-		spin_lock (&urb->lock);
-		qtd_copy_status (urb, qtd->length, token);
-		spin_unlock (&urb->lock);
-
-		/*
-		 * NOTE:  this won't work right with interrupt urbs that
-		 * need multiple qtds ... only the first scan of qh->qtd_list
-		 * starts at the right qtd, yet multiple scans could happen
-		 * for transfers that are scheduled across multiple uframes. 
-		 * (Such schedules are not currently allowed!)
-		 */
-		if (likely (freeing != 0))
-			list_del (&qtd->qtd_list);
-		else {
-			/* restore everything the HC could change
-			 * from an interrupt QTD
-			 */
-			qtd->hw_token = (qtd->hw_token
-					& __constant_cpu_to_le32 (0x8300))
-				| cpu_to_le32 (qtd->length << 16)
-				| __constant_cpu_to_le32 (QTD_STS_ACTIVE
-					| (EHCI_TUNE_CERR << 10));
-			qtd->hw_buf [0] &= ~__constant_cpu_to_le32 (0x0fff);
-
-			/* this offset, and the length above,
-			 * are likely wrong on QTDs #2..N
-			 */
-			qtd->hw_buf [0] |= cpu_to_le32 (0x0fff & qtd->buf_dma);
-		}
-
-#if 0
-		if (urb->status == -EINPROGRESS)
-			vdbg ("  qtd %p ok, urb %p, token %8x, len %d",
-				qtd, urb, token, urb->actual_length);
-		else
-			vdbg ("urb %p status %d, qtd %p, token %8x, len %d",
-				urb, urb->status, qtd, token,
-				urb->actual_length);
-#endif
-
-		/* SETUP for control urb? */
-		if (unlikely (QTD_PID (token) == 2))
-			pci_unmap_single (ehci->hcd.pdev,
-				qtd->buf_dma, sizeof (struct usb_ctrlrequest),
-				PCI_DMA_TODEVICE);
-	}
-
-	/* patch up list head? */
-	if (unlikely (halted && !list_empty (qtd_list))) {
-		qh_update (qh, list_entry (qtd_list->next,
-				struct ehci_qtd, qtd_list));
-	}
-	spin_unlock_irqrestore (&ehci->lock, flags);
-
-	/* last urb's completion might still need calling */
-	if (likely (last != 0)) {
-		if (likely (freeing != 0)) {
-			ehci_urb_done (ehci, last->buf_dma, last->urb);
-			ehci_qtd_free (ehci, last);
-		} else
-			ehci_urb_complete (ehci, last->buf_dma, last->urb);
-		retval++;
-	}
-	return retval;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/*
- * reverse of qh_urb_transaction:  free a list of TDs.
- * used for cleanup after errors, before HC sees an URB's TDs.
- */
-static void qtd_list_free (
-	struct ehci_hcd		*ehci,
-	struct urb		*urb,
-	struct list_head	*qtd_list
-) {
-	struct list_head	*entry, *temp;
-	int			unmapped = 0;
-
-	list_for_each_safe (entry, temp, qtd_list) {
-		struct ehci_qtd	*qtd;
-
-		qtd = list_entry (entry, struct ehci_qtd, qtd_list);
-		list_del (&qtd->qtd_list);
-		if (unmapped != 2) {
-			int	direction;
-			size_t	size;
-
-			/* for ctrl unmap twice: SETUP and DATA;
-			 * else (bulk, intr) just once: DATA
-			 */
-			if (!unmapped++ && usb_pipecontrol (urb->pipe)) {
-				direction = PCI_DMA_TODEVICE;
-				size = sizeof (struct usb_ctrlrequest);
-			} else {
-				direction = usb_pipein (urb->pipe)
-					? PCI_DMA_FROMDEVICE
-					: PCI_DMA_TODEVICE;
-				size = qtd->urb->transfer_buffer_length;
-				unmapped++;
-			}
-			if (qtd->buf_dma)
-				pci_unmap_single (ehci->hcd.pdev,
-					qtd->buf_dma,
-					size, direction);
-		}
-		ehci_qtd_free (ehci, qtd);
-	}
-}
-
-/*
- * create a list of filled qtds for this URB; won't link into qh.
- */
-static struct list_head *
-qh_urb_transaction (
-	struct ehci_hcd		*ehci,
-	struct urb		*urb,
-	struct list_head	*head,
-	int			flags
-) {
-	struct ehci_qtd		*qtd, *qtd_prev;
-	dma_addr_t		buf, map_buf;
-	int			len, maxpacket;
-	u32			token;
-
-	/*
-	 * URBs map to sequences of QTDs:  one logical transaction
-	 */
-	qtd = ehci_qtd_alloc (ehci, flags);
-	if (unlikely (!qtd))
-		return 0;
-	qtd_prev = 0;
-	list_add_tail (&qtd->qtd_list, head);
-	qtd->urb = urb;
-
-	token = QTD_STS_ACTIVE;
-	token |= (EHCI_TUNE_CERR << 10);
-	/* for split transactions, SplitXState initialized to zero */
-
-	if (usb_pipecontrol (urb->pipe)) {
-		/* control request data is passed in the "setup" pid */
-		qtd->buf_dma = pci_map_single (
-					ehci->hcd.pdev,
-					urb->setup_packet,
-					sizeof (struct usb_ctrlrequest),
-					PCI_DMA_TODEVICE);
-		if (unlikely (!qtd->buf_dma))
-			goto cleanup;
-
-		/* SETUP pid */
-		qtd_fill (qtd, qtd->buf_dma, sizeof (struct usb_ctrlrequest),
-			token | (2 /* "setup" */ << 8));
-
-		/* ... and always at least one more pid */
-		token ^= QTD_TOGGLE;
-		qtd_prev = qtd;
-		qtd = ehci_qtd_alloc (ehci, flags);
-		if (unlikely (!qtd))
-			goto cleanup;
-		qtd->urb = urb;
-		qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
-		list_add_tail (&qtd->qtd_list, head);
-	} 
-
-	/*
-	 * data transfer stage:  buffer setup
-	 */
-	len = urb->transfer_buffer_length;
-	if (likely (len > 0)) {
-		buf = map_buf = pci_map_single (ehci->hcd.pdev,
-			urb->transfer_buffer, len,
-			usb_pipein (urb->pipe)
-			    ? PCI_DMA_FROMDEVICE
-			    : PCI_DMA_TODEVICE);
-		if (unlikely (!buf))
-			goto cleanup;
-	} else
-		buf = map_buf = 0;
-
-	if (!buf || usb_pipein (urb->pipe))
-		token |= (1 /* "in" */ << 8);
-	/* else it's already initted to "out" pid (0 << 8) */
-
-	maxpacket = usb_maxpacket (urb->dev, urb->pipe,
-			usb_pipeout (urb->pipe));
-
-	/*
-	 * buffer gets wrapped in one or more qtds;
-	 * last one may be "short" (including zero len)
-	 * and may serve as a control status ack
-	 */
-	for (;;) {
-		int this_qtd_len;
-
-		qtd->urb = urb;
-		qtd->buf_dma = map_buf;
-		this_qtd_len = qtd_fill (qtd, buf, len, token);
-		len -= this_qtd_len;
-		buf += this_qtd_len;
-
-		/* qh makes control packets use qtd toggle; maybe switch it */
-		if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
-			token ^= QTD_TOGGLE;
-
-		if (likely (len <= 0))
-			break;
-
-		qtd_prev = qtd;
-		qtd = ehci_qtd_alloc (ehci, flags);
-		if (unlikely (!qtd))
-			goto cleanup;
-		qtd->urb = urb;
-		qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
-		list_add_tail (&qtd->qtd_list, head);
-	}
-
-	/*
-	 * control requests may need a terminating data "status" ack;
-	 * bulk ones may need a terminating short packet (zero length).
-	 */
-	if (likely (buf != 0)) {
-		int	one_more = 0;
-
-		if (usb_pipecontrol (urb->pipe)) {
-			one_more = 1;
-			token ^= 0x0100;	/* "in" <--> "out"  */
-			token |= QTD_TOGGLE;	/* force DATA1 */
-		} else if (usb_pipebulk (urb->pipe)
-				&& (urb->transfer_flags & USB_ZERO_PACKET)
-				&& !(urb->transfer_buffer_length % maxpacket)) {
-			one_more = 1;
-		}
-		if (one_more) {
-			qtd_prev = qtd;
-			qtd = ehci_qtd_alloc (ehci, flags);
-			if (unlikely (!qtd))
-				goto cleanup;
-			qtd->urb = urb;
-			qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
-			list_add_tail (&qtd->qtd_list, head);
-
-			/* never any data in such packets */
-			qtd_fill (qtd, 0, 0, token);
-		}
-	}
-
-	/* by default, enable interrupt on urb completion */
-	if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT)))
-		qtd->hw_token |= __constant_cpu_to_le32 (QTD_IOC);
-	return head;
-
-cleanup:
-	qtd_list_free (ehci, urb, head);
-	return 0;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/*
- * Hardware maintains data toggle (like OHCI) ... here we (re)initialize
- * the hardware data toggle in the QH, and set the pseudo-toggle in udev
- * so we can see if usb_clear_halt() was called.  NOP for control, since
- * we set up qh->hw_info1 to always use the QTD toggle bits. 
- */
-static inline void
-clear_toggle (struct usb_device *udev, int ep, int is_out, struct ehci_qh *qh)
-{
-	vdbg ("clear toggle, dev %d ep 0x%x-%s",
-		udev->devnum, ep, is_out ? "out" : "in");
-	qh->hw_token &= ~__constant_cpu_to_le32 (QTD_TOGGLE);
-	usb_settoggle (udev, ep, is_out, 1);
-}
-
-// Would be best to create all qh's from config descriptors,
-// when each interface/altsetting is established.  Unlink
-// any previous qh and cancel its urbs first; endpoints are
-// implicitly reset then (data toggle too).
-// That'd mean updating how usbcore talks to HCDs. (2.5?)
-
-
-/*
- * Each QH holds a qtd list; a QH is used for everything except iso.
- *
- * For interrupt urbs, the scheduler must set the microframe scheduling
- * mask(s) each time the QH gets scheduled.  For highspeed, that's
- * just one microframe in the s-mask.  For split interrupt transactions
- * there are additional complications: c-mask, maybe FSTNs.
- */
-static struct ehci_qh *
-ehci_qh_make (
-	struct ehci_hcd		*ehci,
-	struct urb		*urb,
-	struct list_head	*qtd_list,
-	int			flags
-) {
-	struct ehci_qh		*qh = ehci_qh_alloc (ehci, flags);
-	u32			info1 = 0, info2 = 0;
-
-	if (!qh)
-		return qh;
-
-	/*
-	 * init endpoint/device data for this QH
-	 */
-	info1 |= usb_pipeendpoint (urb->pipe) << 8;
-	info1 |= usb_pipedevice (urb->pipe) << 0;
-
-	/* using TT? */
-	switch (urb->dev->speed) {
-	case USB_SPEED_LOW:
-		info1 |= (1 << 12);	/* EPS "low" */
-		/* FALL THROUGH */
-
-	case USB_SPEED_FULL:
-		/* EPS 0 means "full" */
-		info1 |= (EHCI_TUNE_RL_TT << 28);
-		if (usb_pipecontrol (urb->pipe)) {
-			info1 |= (1 << 27);	/* for TT */
-			info1 |= 1 << 14;	/* toggle from qtd */
-		}
-		info1 |= usb_maxpacket (urb->dev, urb->pipe,
-					usb_pipeout (urb->pipe)) << 16;
-
-		info2 |= (EHCI_TUNE_MULT_TT << 30);
-		info2 |= urb->dev->ttport << 23;
-		info2 |= urb->dev->tt->hub->devnum << 16;
-
-		/* NOTE:  if (usb_pipeint (urb->pipe)) { scheduler sets c-mask }
-		 * ... and a 0.96 scheduler might use FSTN nodes too
-		 */
-		break;
-
-	case USB_SPEED_HIGH:		/* no TT involved */
-		info1 |= (2 << 12);	/* EPS "high" */
-		info1 |= (EHCI_TUNE_RL_HS << 28);
-		if (usb_pipecontrol (urb->pipe)) {
-			info1 |= 64 << 16;	/* usb2 fixed maxpacket */
-			info1 |= 1 << 14;	/* toggle from qtd */
-			info2 |= (EHCI_TUNE_MULT_HS << 30);
-		} else if (usb_pipebulk (urb->pipe)) {
-			info1 |= 512 << 16;	/* usb2 fixed maxpacket */
-			info2 |= (EHCI_TUNE_MULT_HS << 30);
-		} else {
-			u32	temp;
-			temp = usb_maxpacket (urb->dev, urb->pipe,
-						usb_pipeout (urb->pipe));
-			info1 |= (temp & 0x3ff) << 16;	/* maxpacket */
-			/* HS intr can be "high bandwidth" */
-			temp = 1 + ((temp >> 11) & 0x03);
-			info2 |= temp << 30;		/* mult */
-		}
-		break;
-	default:
-#ifdef DEBUG
-		BUG ();
-#else
-		;
-#endif
-	}
-
-	/* NOTE:  if (usb_pipeint (urb->pipe)) { scheduler sets s-mask } */
-
-	qh->qh_state = QH_STATE_IDLE;
-	qh->hw_info1 = cpu_to_le32 (info1);
-	qh->hw_info2 = cpu_to_le32 (info2);
-
-	/* initialize sw and hw queues with these qtds */
-	list_splice (qtd_list, &qh->qtd_list);
-	qh_update (qh, list_entry (qtd_list->next, struct ehci_qtd, qtd_list));
-
-	/* initialize data toggle state */
-	if (!usb_pipecontrol (urb->pipe))
-		clear_toggle (urb->dev,
-			usb_pipeendpoint (urb->pipe),
-			usb_pipeout (urb->pipe),
-			qh);
-
-	return qh;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/* move qh (and its qtds) onto async queue; maybe enable queue.  */
-
-static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
-{
-	u32		dma = QH_NEXT (qh->qh_dma);
-	struct ehci_qh	*q;
-
-	if (unlikely (!(q = ehci->async))) {
-		u32	cmd = readl (&ehci->regs->command);
-
-		/* in case a clear of CMD_ASE didn't take yet */
-		while (readl (&ehci->regs->status) & STS_ASS)
-			udelay (100);
-
-		qh->hw_info1 |= __constant_cpu_to_le32 (QH_HEAD); /* [4.8] */
-		qh->qh_next.qh = qh;
-		qh->hw_next = dma;
-		wmb ();
-		ehci->async = qh;
-		writel ((u32)qh->qh_dma, &ehci->regs->async_next);
-		cmd |= CMD_ASE | CMD_RUN;
-		writel (cmd, &ehci->regs->command);
-		ehci->hcd.state = USB_STATE_RUNNING;
-		/* posted write need not be known to HC yet ... */
-	} else {
-		/* splice right after "start" of ring */
-		qh->hw_info1 &= ~__constant_cpu_to_le32 (QH_HEAD); /* [4.8] */
-		qh->qh_next = q->qh_next;
-		qh->hw_next = q->hw_next;
-		wmb ();
-		q->qh_next.qh = qh;
-		q->hw_next = dma;
-	}
-	qh->qh_state = QH_STATE_LINKED;
-	/* qtd completions reported later by interrupt */
-}
-
-/*-------------------------------------------------------------------------*/
-
-static int
-submit_async (
-	struct ehci_hcd		*ehci,
-	struct urb		*urb,
-	struct list_head	*qtd_list,
-	int			mem_flags
-) {
-	struct ehci_qtd		*qtd;
-	struct hcd_dev		*dev;
-	int			epnum;
-	unsigned long		flags;
-	struct ehci_qh		*qh = 0;
-
-	qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
-	dev = (struct hcd_dev *)urb->dev->hcpriv;
-	epnum = usb_pipeendpoint (urb->pipe);
-	if (usb_pipein (urb->pipe))
-		epnum |= 0x10;
-
-	vdbg ("%s: submit_async urb %p len %d ep %d-%s qtd %p [qh %p]",
-		ehci->hcd.bus_name, urb, urb->transfer_buffer_length,
-		epnum & 0x0f, (epnum & 0x10) ? "in" : "out",
-		qtd, dev ? dev->ep [epnum] : (void *)~0);
-
-	spin_lock_irqsave (&ehci->lock, flags);
-
-	qh = (struct ehci_qh *) dev->ep [epnum];
-	if (likely (qh != 0)) {
-		u32	hw_next = QTD_NEXT (qtd->qtd_dma);
-
-		/* maybe patch the qh used for set_address */
-		if (unlikely (epnum == 0
-				&& le32_to_cpu (qh->hw_info1 & 0x7f) == 0))
-			qh->hw_info1 |= cpu_to_le32 (usb_pipedevice(urb->pipe));
-
-		/* is an URB is queued to this qh already? */
-		if (unlikely (!list_empty (&qh->qtd_list))) {
-			struct ehci_qtd		*last_qtd;
-			int			short_rx = 0;
-
-			/* update the last qtd's "next" pointer */
-			// dbg_qh ("non-empty qh", ehci, qh);
-			last_qtd = list_entry (qh->qtd_list.prev,
-					struct ehci_qtd, qtd_list);
-			last_qtd->hw_next = hw_next;
-
-			/* previous urb allows short rx? maybe optimize. */
-			if (!(last_qtd->urb->transfer_flags & USB_DISABLE_SPD)
-					&& (epnum & 0x10)) {
-				// only the last QTD for now
-				last_qtd->hw_alt_next = hw_next;
-				short_rx = 1;
-			}
-
-			/* Adjust any old copies in qh overlay too.
-			 * Interrupt code must cope with case of HC having it
-			 * cached, and clobbering these updates.
-			 * ... complicates getting rid of extra interrupts!
-			 */
-			if (qh->hw_current == cpu_to_le32 (last_qtd->qtd_dma)) {
-				wmb ();
-				qh->hw_qtd_next = hw_next;
-				if (short_rx)
-					qh->hw_alt_next = hw_next
-				    		| (qh->hw_alt_next & 0x1e);
-				vdbg ("queue to qh %p, patch", qh);
-			}
-
-		/* no URB queued */
-		} else {
-			// dbg_qh ("empty qh", ehci, qh);
-
-			/* NOTE: we already canceled any queued URBs
-			 * when the endpoint halted.
-			 */
-
-			/* usb_clear_halt() means qh data toggle gets reset */
-			if (usb_pipebulk (urb->pipe)
-					&& unlikely (!usb_gettoggle (urb->dev,
-						(epnum & 0x0f),
-						!(epnum & 0x10)))) {
-				clear_toggle (urb->dev,
-					epnum & 0x0f, !(epnum & 0x10), qh);
-			}
-			qh_update (qh, qtd);
-		}
-		list_splice (qtd_list, qh->qtd_list.prev);
-
-	} else {
-		/* can't sleep here, we have ehci->lock... */
-		qh = ehci_qh_make (ehci, urb, qtd_list, SLAB_ATOMIC);
-		if (likely (qh != 0)) {
-			// dbg_qh ("new qh", ehci, qh);
-			dev->ep [epnum] = qh;
-		}
-	}
-
-	/* Control/bulk operations through TTs don't need scheduling,
-	 * the HC and TT handle it when the TT has a buffer ready.
-	 */
-	if (likely (qh != 0)) {
-		urb->hcpriv = qh_get (qh);
-		if (likely (qh->qh_state == QH_STATE_IDLE))
-			qh_link_async (ehci, qh_get (qh));
-	}
-	spin_unlock_irqrestore (&ehci->lock, flags);
-	if (unlikely (qh == 0)) {
-		qtd_list_free (ehci, urb, qtd_list);
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/* the async qh for the qtds being reclaimed are now unlinked from the HC */
-/* caller must not own ehci->lock */
-
-static void end_unlink_async (struct ehci_hcd *ehci)
-{
-	struct ehci_qh		*qh = ehci->reclaim;
-
-	qh->qh_state = QH_STATE_IDLE;
-	qh->qh_next.qh = 0;
-	qh_put (ehci, qh);			// refcount from reclaim 
-	ehci->reclaim = 0;
-	ehci->reclaim_ready = 0;
-
-	qh_completions (ehci, qh, 1);
-
-	// unlink any urb should now unlink all following urbs, so that
-	// relinking only happens for urbs before the unlinked ones.
-	if (!list_empty (&qh->qtd_list)
-			&& HCD_IS_RUNNING (ehci->hcd.state))
-		qh_link_async (ehci, qh);
-	else
-		qh_put (ehci, qh);		// refcount from async list
-}
-
-
-/* makes sure the async qh will become idle */
-/* caller must own ehci->lock */
-
-static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
-{
-	int		cmd = readl (&ehci->regs->command);
-	struct ehci_qh	*prev;
-
-#ifdef DEBUG
-	if (ehci->reclaim
-			|| !ehci->async
-			|| qh->qh_state != QH_STATE_LINKED
-#ifdef CONFIG_SMP
-// this macro lies except on SMP compiles
-			|| !spin_is_locked (&ehci->lock)
-#endif
-			)
-		BUG ();
-#endif
-
-	qh->qh_state = QH_STATE_UNLINK;
-	ehci->reclaim = qh = qh_get (qh);
-
-	// dbg_qh ("start unlink", ehci, qh);
-
-	/* Remove the last QH (qhead)?  Stop async schedule first. */
-	if (unlikely (qh == ehci->async && qh->qh_next.qh == qh)) {
-		/* can't get here without STS_ASS set */
-		if (ehci->hcd.state != USB_STATE_HALT) {
-			if (cmd & CMD_PSE)
-				writel (cmd & ~CMD_ASE, &ehci->regs->command);
-			else {
-				ehci_ready (ehci);
-				while (readl (&ehci->regs->status) & STS_ASS)
-					udelay (100);
-			}
-		}
-		qh->qh_next.qh = ehci->async = 0;
-
-		ehci->reclaim_ready = 1;
-		tasklet_schedule (&ehci->tasklet);
-		return;
-	} 
-
-	if (unlikely (ehci->hcd.state == USB_STATE_HALT)) {
-		ehci->reclaim_ready = 1;
-		tasklet_schedule (&ehci->tasklet);
-		return;
-	}
-
-	prev = ehci->async;
-	while (prev->qh_next.qh != qh && prev->qh_next.qh != ehci->async)
-		prev = prev->qh_next.qh;
-#ifdef DEBUG
-	if (prev->qh_next.qh != qh)
-		BUG ();
-#endif
-
-	if (qh->hw_info1 & __constant_cpu_to_le32 (QH_HEAD)) {
-		ehci->async = prev;
-		prev->hw_info1 |= __constant_cpu_to_le32 (QH_HEAD);
-	}
-	prev->hw_next = qh->hw_next;
-	prev->qh_next = qh->qh_next;
-	wmb ();
-
-	ehci->reclaim_ready = 0;
-	cmd |= CMD_IAAD;
-	writel (cmd, &ehci->regs->command);
-	/* posted write need not be known to HC yet ... */
-}
-
-/*-------------------------------------------------------------------------*/
-
-static void scan_async (struct ehci_hcd *ehci)
-{
-	struct ehci_qh		*qh;
-	unsigned long		flags;
-
-	spin_lock_irqsave (&ehci->lock, flags);
-rescan:
-	qh = ehci->async;
-	if (likely (qh != 0)) {
-		do {
-			/* clean any finished work for this qh */
-			if (!list_empty (&qh->qtd_list)) {
-				// dbg_qh ("scan_async", ehci, qh);
-				qh = qh_get (qh);
-				spin_unlock_irqrestore (&ehci->lock, flags);
-
-				/* concurrent unlink could happen here */
-				qh_completions (ehci, qh, 1);
-
-				spin_lock_irqsave (&ehci->lock, flags);
-				qh_put (ehci, qh);
-			}
-
-			/* unlink idle entries (reduces PCI usage) */
-			if (list_empty (&qh->qtd_list) && !ehci->reclaim) {
-				if (qh->qh_next.qh != qh) {
-					// dbg ("irq/empty");
-					start_unlink_async (ehci, qh);
-				} else {
-					// FIXME:  arrange to stop
-					// after it's been idle a while.
-				}
-			}
-			qh = qh->qh_next.qh;
-			if (!qh)		/* unlinked? */
-				goto rescan;
-		} while (qh != ehci->async);
-	}
-
-	spin_unlock_irqrestore (&ehci->lock, flags);
-}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)