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path: root/target/linux/generic-2.4/patches/228-more_usb_fixes.patch
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Index: linux-2.4.35.4/drivers/scsi/hosts.c
===================================================================
--- linux-2.4.35.4.orig/drivers/scsi/hosts.c	2007-12-15 05:19:38.686625662 +0100
+++ linux-2.4.35.4/drivers/scsi/hosts.c	2007-12-15 05:20:04.720109227 +0100
@@ -107,8 +107,21 @@
     if (shn) shn->host_registered = 0;
     /* else {} : This should not happen, we should panic here... */
     
+    /* If we are removing the last host registered, it is safe to reuse
+     * its host number (this avoids "holes" at boot time) (DB) 
+     * It is also safe to reuse those of numbers directly below which have
+     * been released earlier (to avoid some holes in numbering).
+     */
+    if(sh->host_no == max_scsi_hosts - 1) {
+	while(--max_scsi_hosts >= next_scsi_host) {
+	    shpnt = scsi_hostlist;
+	    while(shpnt && shpnt->host_no != max_scsi_hosts - 1)
+		shpnt = shpnt->next;
+	    if(shpnt)
+		break;
+	}
+    }
     next_scsi_host--;
-
     kfree((char *) sh);
 }
 
Index: linux-2.4.35.4/drivers/usb/hcd.c
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/hcd.c	2007-12-15 05:19:38.694626120 +0100
+++ linux-2.4.35.4/drivers/usb/hcd.c	2007-12-15 05:20:04.724109453 +0100
@@ -1105,7 +1105,8 @@
 		break;
 	case PIPE_BULK:
 		allowed |= USB_DISABLE_SPD | USB_QUEUE_BULK
-				| USB_ZERO_PACKET | URB_NO_INTERRUPT;
+				| USB_ZERO_PACKET | URB_NO_INTERRUPT
+		        | URB_NO_TRANSFER_DMA_MAP;
 		break;
 	case PIPE_INTERRUPT:
 		allowed |= USB_DISABLE_SPD;
@@ -1212,7 +1213,8 @@
 					urb->setup_packet,
 					sizeof (struct usb_ctrlrequest),
 					PCI_DMA_TODEVICE);
-		if (urb->transfer_buffer_length != 0)
+		if (urb->transfer_buffer_length != 0
+			&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
 			urb->transfer_dma = pci_map_single (
 					hcd->pdev,
 					urb->transfer_buffer,
Index: linux-2.4.35.4/drivers/usb/host/ehci-hcd.c
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/host/ehci-hcd.c	2007-12-15 05:19:38.702626576 +0100
+++ linux-2.4.35.4/drivers/usb/host/ehci-hcd.c	2007-12-15 05:20:04.728109682 +0100
@@ -399,6 +399,27 @@
 		ehci_mem_cleanup (ehci);
 		return retval;
 	}
+
+{
+	int misc_reg;
+	u32 vendor_id;
+	
+	pci_read_config_dword (ehci->hcd.pdev, PCI_VENDOR_ID, &vendor_id);
+	if (vendor_id == 0x31041106) {
+		/* VIA 6212 */
+		printk(KERN_INFO "EHCI: Enabling VIA 6212 workarounds\n", misc_reg);
+		pci_read_config_byte(ehci->hcd.pdev, 0x49, &misc_reg);
+		misc_reg &= ~0x20;
+		pci_write_config_byte(ehci->hcd.pdev, 0x49, misc_reg);
+		pci_read_config_byte(ehci->hcd.pdev, 0x49, &misc_reg);
+
+		pci_read_config_byte(ehci->hcd.pdev, 0x4b, &misc_reg);
+		misc_reg |= 0x20;
+		pci_write_config_byte(ehci->hcd.pdev, 0x4b, misc_reg);
+		pci_read_config_byte(ehci->hcd.pdev, 0x4b, &misc_reg);
+	}
+}
+
 	writel (INTR_MASK, &ehci->regs->intr_enable);
 	writel (ehci->periodic_dma, &ehci->regs->frame_list);
 
Index: linux-2.4.35.4/drivers/usb/host/ehci-q.c
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/host/ehci-q.c	2007-12-15 05:20:00.107846389 +0100
+++ linux-2.4.35.4/drivers/usb/host/ehci-q.c	2007-12-15 05:20:04.728109682 +0100
@@ -791,6 +791,8 @@
 			writel (cmd, &ehci->regs->command);
 			ehci->hcd.state = USB_STATE_RUNNING;
 			/* posted write need not be known to HC yet ... */
+			
+			timer_action (ehci, TIMER_IO_WATCHDOG);
 		}
 	}
 
Index: linux-2.4.35.4/drivers/usb/host/usb-uhci.c
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/host/usb-uhci.c	2007-12-15 05:19:38.714627260 +0100
+++ linux-2.4.35.4/drivers/usb/host/usb-uhci.c	2007-12-15 05:20:04.728109682 +0100
@@ -3034,6 +3034,21 @@
 	
 	pci_set_master(dev);
 
+	{
+		u8 misc_reg;
+		u32 vendor_id;
+		
+		pci_read_config_dword (dev, PCI_VENDOR_ID, &vendor_id);
+		if (vendor_id == 0x30381106) {
+			/* VIA 6212 */
+			printk(KERN_INFO "UHCI: Enabling VIA 6212 workarounds\n");
+			pci_read_config_byte(dev, 0x41, &misc_reg);
+			misc_reg &= ~0x10;
+			pci_write_config_byte(dev, 0x41, misc_reg);
+			pci_read_config_byte(dev, 0x41, &misc_reg);
+		}
+	}
+	
 	/* Search for the IO base address.. */
 	for (i = 0; i < 6; i++) {
 
Index: linux-2.4.35.4/drivers/usb/storage/transport.c
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/storage/transport.c	2007-12-15 05:19:38.722627715 +0100
+++ linux-2.4.35.4/drivers/usb/storage/transport.c	2007-12-15 05:20:04.732109911 +0100
@@ -54,6 +54,22 @@
 #include <linux/sched.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
+#include <linux/pci.h>
+#include "../hcd.h"
+
+/* These definitions mirror those in pci.h, so they can be used
+ * interchangeably with their PCI_ counterparts */
+enum dma_data_direction {
+	DMA_BIDIRECTIONAL = 0,
+	DMA_TO_DEVICE = 1,
+	DMA_FROM_DEVICE = 2,
+	DMA_NONE = 3,
+};
+
+#define dma_map_sg(d,s,n,dir) pci_map_sg(d,s,n,dir)
+#define dma_unmap_sg(d,s,n,dir) pci_unmap_sg(d,s,n,dir)
+
+
 
 /***********************************************************************
  * Helper routines
@@ -554,6 +570,543 @@
 	return US_BULK_TRANSFER_SHORT;
 }
 
+/*-------------------------------------------------------------------*/
+/**
+ * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
+ * @dev: device to which the scatterlist will be mapped
+ * @pipe: endpoint defining the mapping direction
+ * @sg: the scatterlist to unmap
+ * @n_hw_ents: the positive return value from usb_buffer_map_sg
+ *
+ * Reverses the effect of usb_buffer_map_sg().
+ */
+static void usb_buffer_unmap_sg (struct usb_device *dev, unsigned pipe,
+		struct scatterlist *sg, int n_hw_ents)
+{
+	struct usb_bus *bus;
+	struct usb_hcd *hcd;
+	struct pci_dev *pdev;
+
+	if (!dev
+			|| !(bus = dev->bus)
+			|| !(hcd = bus->hcpriv)
+			|| !(pdev = hcd->pdev)
+			|| !pdev->dma_mask)
+		return;
+
+	dma_unmap_sg (pdev, sg, n_hw_ents,
+			usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+}
+
+/**
+ * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
+ * @dev: device to which the scatterlist will be mapped
+ * @pipe: endpoint defining the mapping direction
+ * @sg: the scatterlist to map
+ * @nents: the number of entries in the scatterlist
+ *
+ * Return value is either < 0 (indicating no buffers could be mapped), or
+ * the number of DMA mapping array entries in the scatterlist.
+ *
+ * The caller is responsible for placing the resulting DMA addresses from
+ * the scatterlist into URB transfer buffer pointers, and for setting the
+ * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
+ *
+ * Top I/O rates come from queuing URBs, instead of waiting for each one
+ * to complete before starting the next I/O.   This is particularly easy
+ * to do with scatterlists.  Just allocate and submit one URB for each DMA
+ * mapping entry returned, stopping on the first error or when all succeed.
+ * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
+ *
+ * This call would normally be used when translating scatterlist requests,
+ * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
+ * may be able to coalesce mappings for improved I/O efficiency.
+ *
+ * Reverse the effect of this call with usb_buffer_unmap_sg().
+ */
+static int usb_buffer_map_sg (struct usb_device *dev, unsigned pipe,
+		struct scatterlist *sg, int nents)
+{
+	struct usb_bus		*bus;
+	struct usb_hcd *hcd;
+	struct pci_dev *pdev;
+
+	if (!dev
+			|| usb_pipecontrol (pipe)
+			|| !(bus = dev->bus)
+			|| !(hcd = bus->hcpriv)
+			|| !(pdev = hcd->pdev)
+			|| !pdev->dma_mask)
+		return -1;
+
+	// FIXME generic api broken like pci, can't report errors
+	return dma_map_sg (pdev, sg, nents,
+			usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+}
+
+static void sg_clean (struct usb_sg_request *io)
+{
+	struct usb_hcd *hcd = io->dev->bus->hcpriv;
+	struct pci_dev *pdev = hcd->pdev;
+
+	if (io->urbs) {
+		while (io->entries--)
+			usb_free_urb (io->urbs [io->entries]);
+		kfree (io->urbs);
+		io->urbs = 0;
+	}
+	if (pdev->dma_mask != 0)
+		usb_buffer_unmap_sg (io->dev, io->pipe, io->sg, io->nents);
+	io->dev = 0;
+}
+
+static void sg_complete (struct urb *urb)
+{
+	struct usb_sg_request	*io = (struct usb_sg_request *) urb->context;
+
+	spin_lock (&io->lock);
+
+	/* In 2.5 we require hcds' endpoint queues not to progress after fault
+	 * reports, until the completion callback (this!) returns.  That lets
+	 * device driver code (like this routine) unlink queued urbs first,
+	 * if it needs to, since the HC won't work on them at all.  So it's
+	 * not possible for page N+1 to overwrite page N, and so on.
+	 *
+	 * That's only for "hard" faults; "soft" faults (unlinks) sometimes
+	 * complete before the HCD can get requests away from hardware,
+	 * though never during cleanup after a hard fault.
+	 */
+	if (io->status
+			&& (io->status != -ECONNRESET
+				|| urb->status != -ECONNRESET)
+			&& urb->actual_length) {
+		US_DEBUGP("Error: %s ep%d%s scatterlist error %d/%d\n",
+			io->dev->devpath,
+			usb_pipeendpoint (urb->pipe),
+			usb_pipein (urb->pipe) ? "in" : "out",
+			urb->status, io->status);
+		// BUG ();
+	}
+
+	if (urb->status && urb->status != -ECONNRESET) {
+		int		i, found, status;
+
+		io->status = urb->status;
+
+		/* the previous urbs, and this one, completed already.
+		 * unlink pending urbs so they won't rx/tx bad data.
+		 */
+		for (i = 0, found = 0; i < io->entries; i++) {
+			if (!io->urbs [i])
+				continue;
+			if (found) {
+				status = usb_unlink_urb (io->urbs [i]);
+				if (status != -EINPROGRESS && status != -EBUSY)
+					US_DEBUGP("Error: %s, unlink --> %d\n", __FUNCTION__, status);
+			} else if (urb == io->urbs [i])
+				found = 1;
+		}
+	}
+	urb->dev = 0;
+
+	/* on the last completion, signal usb_sg_wait() */
+	io->bytes += urb->actual_length;
+	io->count--;
+	if (!io->count)
+		complete (&io->complete);
+
+	spin_unlock (&io->lock);
+}
+
+/**
+ * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request
+ * @io: request block being initialized.  until usb_sg_wait() returns,
+ *	treat this as a pointer to an opaque block of memory,
+ * @dev: the usb device that will send or receive the data
+ * @pipe: endpoint "pipe" used to transfer the data
+ * @period: polling rate for interrupt endpoints, in frames or
+ * 	(for high speed endpoints) microframes; ignored for bulk
+ * @sg: scatterlist entries
+ * @nents: how many entries in the scatterlist
+ * @length: how many bytes to send from the scatterlist, or zero to
+ * 	send every byte identified in the list.
+ * @mem_flags: SLAB_* flags affecting memory allocations in this call
+ *
+ * Returns zero for success, else a negative errno value.  This initializes a
+ * scatter/gather request, allocating resources such as I/O mappings and urb
+ * memory (except maybe memory used by USB controller drivers).
+ *
+ * The request must be issued using usb_sg_wait(), which waits for the I/O to
+ * complete (or to be canceled) and then cleans up all resources allocated by
+ * usb_sg_init().
+ *
+ * The request may be canceled with usb_sg_cancel(), either before or after
+ * usb_sg_wait() is called.
+ */
+int usb_sg_init (
+	struct usb_sg_request	*io,
+	struct usb_device	*dev,
+	unsigned		pipe, 
+	unsigned		period,
+	struct scatterlist	*sg,
+	int			nents,
+	size_t			length,
+	int			mem_flags
+)
+{
+	int			i;
+	int			urb_flags;
+	int			dma;
+	struct usb_hcd *hcd;
+
+	hcd = dev->bus->hcpriv;
+
+	if (!io || !dev || !sg
+			|| usb_pipecontrol (pipe)
+			|| usb_pipeisoc (pipe)
+			|| nents <= 0)
+		return -EINVAL;
+
+	spin_lock_init (&io->lock);
+	io->dev = dev;
+	io->pipe = pipe;
+	io->sg = sg;
+	io->nents = nents;
+
+	/* not all host controllers use DMA (like the mainstream pci ones);
+	 * they can use PIO (sl811) or be software over another transport.
+	 */
+	dma = (hcd->pdev->dma_mask != 0);
+	if (dma)
+		io->entries = usb_buffer_map_sg (dev, pipe, sg, nents);
+	else
+		io->entries = nents;
+
+	/* initialize all the urbs we'll use */
+	if (io->entries <= 0)
+		return io->entries;
+
+	io->count = 0;
+	io->urbs = kmalloc (io->entries * sizeof *io->urbs, mem_flags);
+	if (!io->urbs)
+		goto nomem;
+
+	urb_flags = USB_ASYNC_UNLINK | URB_NO_INTERRUPT | URB_NO_TRANSFER_DMA_MAP;
+	if (usb_pipein (pipe))
+		urb_flags |= URB_SHORT_NOT_OK;
+
+	for (i = 0; i < io->entries; i++, io->count = i) {
+		unsigned		len;
+
+		io->urbs [i] = usb_alloc_urb (0);
+		if (!io->urbs [i]) {
+			io->entries = i;
+			goto nomem;
+		}
+
+		io->urbs [i]->dev = 0;
+		io->urbs [i]->pipe = pipe;
+		io->urbs [i]->interval = period;
+		io->urbs [i]->transfer_flags = urb_flags;
+
+		io->urbs [i]->complete = sg_complete;
+		io->urbs [i]->context = io;
+		io->urbs [i]->status = -EINPROGRESS;
+		io->urbs [i]->actual_length = 0;
+
+		if (dma) {
+			/* hc may use _only_ transfer_dma */
+			io->urbs [i]->transfer_dma = sg_dma_address (sg + i);
+			len = sg_dma_len (sg + i);
+		} else {
+			/* hc may use _only_ transfer_buffer */
+			io->urbs [i]->transfer_buffer =
+				page_address (sg [i].page) + sg [i].offset;
+			len = sg [i].length;
+		}
+
+		if (length) {
+			len = min_t (unsigned, len, length);
+			length -= len;
+			if (length == 0)
+				io->entries = i + 1;
+		}
+		io->urbs [i]->transfer_buffer_length = len;
+	}
+	io->urbs [--i]->transfer_flags &= ~URB_NO_INTERRUPT;
+
+	/* transaction state */
+	io->status = 0;
+	io->bytes = 0;
+	init_completion (&io->complete);
+	return 0;
+
+nomem:
+	sg_clean (io);
+	return -ENOMEM;
+}
+
+/**
+ * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait()
+ * @io: request block, initialized with usb_sg_init()
+ *
+ * This stops a request after it has been started by usb_sg_wait().
+ * It can also prevents one initialized by usb_sg_init() from starting,
+ * so that call just frees resources allocated to the request.
+ */
+void usb_sg_cancel (struct usb_sg_request *io)
+{
+	unsigned long	flags;
+
+	spin_lock_irqsave (&io->lock, flags);
+
+	/* shut everything down, if it didn't already */
+	if (!io->status) {
+		int	i;
+
+		io->status = -ECONNRESET;
+		for (i = 0; i < io->entries; i++) {
+			int	retval;
+
+			if (!io->urbs [i]->dev)
+				continue;
+			retval = usb_unlink_urb (io->urbs [i]);
+			if (retval != -EINPROGRESS && retval != -EBUSY)
+				US_DEBUGP("WARNING: %s, unlink --> %d\n", __FUNCTION__, retval);
+		}
+	}
+	spin_unlock_irqrestore (&io->lock, flags);
+}
+
+/**
+ * usb_sg_wait - synchronously execute scatter/gather request
+ * @io: request block handle, as initialized with usb_sg_init().
+ * 	some fields become accessible when this call returns.
+ * Context: !in_interrupt ()
+ *
+ * This function blocks until the specified I/O operation completes.  It
+ * leverages the grouping of the related I/O requests to get good transfer
+ * rates, by queueing the requests.  At higher speeds, such queuing can
+ * significantly improve USB throughput.
+ *
+ * There are three kinds of completion for this function.
+ * (1) success, where io->status is zero.  The number of io->bytes
+ *     transferred is as requested.
+ * (2) error, where io->status is a negative errno value.  The number
+ *     of io->bytes transferred before the error is usually less
+ *     than requested, and can be nonzero.
+ * (3) cancelation, a type of error with status -ECONNRESET that
+ *     is initiated by usb_sg_cancel().
+ *
+ * When this function returns, all memory allocated through usb_sg_init() or
+ * this call will have been freed.  The request block parameter may still be
+ * passed to usb_sg_cancel(), or it may be freed.  It could also be
+ * reinitialized and then reused.
+ *
+ * Data Transfer Rates:
+ *
+ * Bulk transfers are valid for full or high speed endpoints.
+ * The best full speed data rate is 19 packets of 64 bytes each
+ * per frame, or 1216 bytes per millisecond.
+ * The best high speed data rate is 13 packets of 512 bytes each
+ * per microframe, or 52 KBytes per millisecond.
+ *
+ * The reason to use interrupt transfers through this API would most likely
+ * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond
+ * could be transferred.  That capability is less useful for low or full
+ * speed interrupt endpoints, which allow at most one packet per millisecond,
+ * of at most 8 or 64 bytes (respectively).
+ */
+void usb_sg_wait (struct usb_sg_request *io)
+{
+	int		i, entries = io->entries;
+
+	/* queue the urbs.  */
+	spin_lock_irq (&io->lock);
+	for (i = 0; i < entries && !io->status; i++) {
+		int	retval;
+
+		io->urbs [i]->dev = io->dev;
+		retval = usb_submit_urb (io->urbs [i]);
+
+		/* after we submit, let completions or cancelations fire;
+		 * we handshake using io->status.
+		 */
+		spin_unlock_irq (&io->lock);
+		switch (retval) {
+			/* maybe we retrying will recover */
+		case -ENXIO:	// hc didn't queue this one
+		case -EAGAIN:
+		case -ENOMEM:
+			io->urbs [i]->dev = 0;
+			retval = 0;
+			i--;
+			yield ();
+			break;
+
+			/* no error? continue immediately.
+			 *
+			 * NOTE: to work better with UHCI (4K I/O buffer may
+			 * need 3K of TDs) it may be good to limit how many
+			 * URBs are queued at once; N milliseconds?
+			 */
+		case 0:
+			cpu_relax ();
+			break;
+
+			/* fail any uncompleted urbs */
+		default:
+			spin_lock_irq (&io->lock);
+			io->count -= entries - i;
+			if (io->status == -EINPROGRESS)
+				io->status = retval;
+			if (io->count == 0)
+				complete (&io->complete);
+			spin_unlock_irq (&io->lock);
+
+			io->urbs [i]->dev = 0;
+			io->urbs [i]->status = retval;
+			
+			US_DEBUGP("%s, submit --> %d\n", __FUNCTION__, retval);
+			usb_sg_cancel (io);
+		}
+		spin_lock_irq (&io->lock);
+		if (retval && io->status == -ECONNRESET)
+			io->status = retval;
+	}
+	spin_unlock_irq (&io->lock);
+
+	/* OK, yes, this could be packaged as non-blocking.
+	 * So could the submit loop above ... but it's easier to
+	 * solve neither problem than to solve both!
+	 */
+	wait_for_completion (&io->complete);
+
+	sg_clean (io);
+}
+
+/*
+ * Interpret the results of a URB transfer
+ *
+ * This function prints appropriate debugging messages, clears halts on
+ * non-control endpoints, and translates the status to the corresponding
+ * USB_STOR_XFER_xxx return code.
+ */
+static int interpret_urb_result(struct us_data *us, unsigned int pipe,
+		unsigned int length, int result, unsigned int partial)
+{
+	US_DEBUGP("Status code %d; transferred %u/%u\n",
+			result, partial, length);
+	switch (result) {
+
+	/* no error code; did we send all the data? */
+	case 0:
+		if (partial != length) {
+			US_DEBUGP("-- short transfer\n");
+			return USB_STOR_XFER_SHORT;
+		}
+
+		US_DEBUGP("-- transfer complete\n");
+		return USB_STOR_XFER_GOOD;
+
+	/* stalled */
+	case -EPIPE:
+		/* for control endpoints, (used by CB[I]) a stall indicates
+		 * a failed command */
+		if (usb_pipecontrol(pipe)) {
+			US_DEBUGP("-- stall on control pipe\n");
+			return USB_STOR_XFER_STALLED;
+		}
+
+		/* for other sorts of endpoint, clear the stall */
+		US_DEBUGP("clearing endpoint halt for pipe 0x%x\n", pipe);
+		if (usb_stor_clear_halt(us, pipe) < 0)
+			return USB_STOR_XFER_ERROR;
+		return USB_STOR_XFER_STALLED;
+
+	/* timeout or excessively long NAK */
+	case -ETIMEDOUT:
+		US_DEBUGP("-- timeout or NAK\n");
+		return USB_STOR_XFER_ERROR;
+
+	/* babble - the device tried to send more than we wanted to read */
+	case -EOVERFLOW:
+		US_DEBUGP("-- babble\n");
+		return USB_STOR_XFER_LONG;
+
+	/* the transfer was cancelled by abort, disconnect, or timeout */
+	case -ECONNRESET:
+		US_DEBUGP("-- transfer cancelled\n");
+		return USB_STOR_XFER_ERROR;
+
+	/* short scatter-gather read transfer */
+	case -EREMOTEIO:
+		US_DEBUGP("-- short read transfer\n");
+		return USB_STOR_XFER_SHORT;
+
+	/* abort or disconnect in progress */
+	case -EIO:
+		US_DEBUGP("-- abort or disconnect in progress\n");
+		return USB_STOR_XFER_ERROR;
+
+	/* the catch-all error case */
+	default:
+		US_DEBUGP("-- unknown error\n");
+		return USB_STOR_XFER_ERROR;
+	}
+}
+
+/*
+ * Transfer a scatter-gather list via bulk transfer
+ *
+ * This function does basically the same thing as usb_stor_bulk_msg()
+ * above, but it uses the usbcore scatter-gather library.
+ */
+int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
+		struct scatterlist *sg, int num_sg, unsigned int length,
+		unsigned int *act_len)
+{
+	int result;
+
+	/* don't submit s-g requests during abort/disconnect processing */
+	if (us->flags & ABORTING_OR_DISCONNECTING)
+		return USB_STOR_XFER_ERROR;
+
+	/* initialize the scatter-gather request block */
+	US_DEBUGP("%s: xfer %u bytes, %d entries\n", __FUNCTION__,
+			length, num_sg);
+	result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0,
+			sg, num_sg, length, SLAB_NOIO);
+	if (result) {
+		US_DEBUGP("usb_sg_init returned %d\n", result);
+		return USB_STOR_XFER_ERROR;
+	}
+
+	/* since the block has been initialized successfully, it's now
+	 * okay to cancel it */
+	set_bit(US_FLIDX_SG_ACTIVE, &us->flags);
+
+	/* did an abort/disconnect occur during the submission? */
+	if (us->flags & ABORTING_OR_DISCONNECTING) {
+
+		/* cancel the request, if it hasn't been cancelled already */
+		if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) {
+			US_DEBUGP("-- cancelling sg request\n");
+			usb_sg_cancel(&us->current_sg);
+		}
+	}
+
+	/* wait for the completion of the transfer */
+	usb_sg_wait(&us->current_sg);
+	clear_bit(US_FLIDX_SG_ACTIVE, &us->flags);
+
+	result = us->current_sg.status;
+	if (act_len)
+		*act_len = us->current_sg.bytes;
+	return interpret_urb_result(us, pipe, length, result,
+			us->current_sg.bytes);
+}
+
 /*
  * Transfer an entire SCSI command's worth of data payload over the bulk
  * pipe.
@@ -569,6 +1122,8 @@
 	struct scatterlist *sg;
 	unsigned int total_transferred = 0;
 	unsigned int transfer_amount;
+	unsigned int partial;
+	unsigned int pipe;
 
 	/* calculate how much we want to transfer */
 	transfer_amount = usb_stor_transfer_length(srb);
@@ -585,23 +1140,34 @@
 		 * make the appropriate requests for each, until done
 		 */
 		sg = (struct scatterlist *) srb->request_buffer;
-		for (i = 0; i < srb->use_sg; i++) {
-
-			/* transfer the lesser of the next buffer or the
-			 * remaining data */
-			if (transfer_amount - total_transferred >= 
-					sg[i].length) {
-				result = usb_stor_transfer_partial(us,
-						sg[i].address, sg[i].length);
-				total_transferred += sg[i].length;
-			} else
-				result = usb_stor_transfer_partial(us,
-						sg[i].address,
-						transfer_amount - total_transferred);
-
-			/* if we get an error, end the loop here */
-			if (result)
-				break;
+		if (us->pusb_dev->speed == USB_SPEED_HIGH) {
+			/* calculate the appropriate pipe information */
+			if (us->srb->sc_data_direction == SCSI_DATA_READ)
+				pipe = usb_rcvbulkpipe(us->pusb_dev, us->ep_in);
+			else
+				pipe = usb_sndbulkpipe(us->pusb_dev, us->ep_out);
+			/* use the usb core scatter-gather primitives */
+			result = usb_stor_bulk_transfer_sglist(us, pipe,
+					sg, srb->use_sg, transfer_amount, &partial);
+		} else {
+			for (i = 0; i < srb->use_sg; i++) {
+
+				/* transfer the lesser of the next buffer or the
+				 * remaining data */
+				if (transfer_amount - total_transferred >= 
+						sg[i].length) {
+					result = usb_stor_transfer_partial(us,
+							sg[i].address, sg[i].length);
+					total_transferred += sg[i].length;
+				} else
+					result = usb_stor_transfer_partial(us,
+							sg[i].address,
+							transfer_amount - total_transferred);
+
+				/* if we get an error, end the loop here */
+				if (result)
+					break;
+			}
 		}
 	}
 	else
Index: linux-2.4.35.4/drivers/usb/storage/transport.h
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/storage/transport.h	2007-12-15 05:19:38.730628171 +0100
+++ linux-2.4.35.4/drivers/usb/storage/transport.h	2007-12-15 05:20:04.732109911 +0100
@@ -127,6 +127,16 @@
 #define US_BULK_TRANSFER_ABORTED	3  /* transfer canceled             */
 
 /*
+ * usb_stor_bulk_transfer_xxx() return codes, in order of severity
+ */
+
+#define USB_STOR_XFER_GOOD		0	/* good transfer                 */
+#define USB_STOR_XFER_SHORT		1	/* transferred less than expected */
+#define USB_STOR_XFER_STALLED	2	/* endpoint stalled              */
+#define USB_STOR_XFER_LONG		3	/* device tried to send too much */
+#define USB_STOR_XFER_ERROR		4	/* transfer died in the middle   */
+
+/*
  * Transport return codes
  */
 
Index: linux-2.4.35.4/drivers/usb/storage/usb.h
===================================================================
--- linux-2.4.35.4.orig/drivers/usb/storage/usb.h	2007-12-15 05:19:38.738628626 +0100
+++ linux-2.4.35.4/drivers/usb/storage/usb.h	2007-12-15 05:20:04.736110140 +0100
@@ -111,6 +111,60 @@
 typedef void (*proto_cmnd)(Scsi_Cmnd*, struct us_data*);
 typedef void (*extra_data_destructor)(void *);	 /* extra data destructor   */
 
+/* Dynamic flag definitions: used in set_bit() etc. */
+#define US_FLIDX_URB_ACTIVE	18  /* 0x00040000  current_urb is in use  */
+#define US_FLIDX_SG_ACTIVE	19  /* 0x00080000  current_sg is in use   */
+#define US_FLIDX_ABORTING	20  /* 0x00100000  abort is in progress   */
+#define US_FLIDX_DISCONNECTING	21  /* 0x00200000  disconnect in progress */
+#define ABORTING_OR_DISCONNECTING	((1UL << US_FLIDX_ABORTING) | \
+					 (1UL << US_FLIDX_DISCONNECTING))
+#define US_FLIDX_RESETTING	22  /* 0x00400000  device reset in progress */
+
+/* processing state machine states */
+#define US_STATE_IDLE		1
+#define US_STATE_RUNNING	2
+#define US_STATE_RESETTING	3
+#define US_STATE_ABORTING	4
+
+/**
+ * struct usb_sg_request - support for scatter/gather I/O
+ * @status: zero indicates success, else negative errno
+ * @bytes: counts bytes transferred.
+ *
+ * These requests are initialized using usb_sg_init(), and then are used
+ * as request handles passed to usb_sg_wait() or usb_sg_cancel().  Most
+ * members of the request object aren't for driver access.
+ *
+ * The status and bytecount values are valid only after usb_sg_wait()
+ * returns.  If the status is zero, then the bytecount matches the total
+ * from the request.
+ *
+ * After an error completion, drivers may need to clear a halt condition
+ * on the endpoint.
+ */
+struct usb_sg_request {
+	int			status;
+	size_t			bytes;
+
+	/* 
+	 * members below are private to usbcore,
+	 * and are not provided for driver access!
+	 */
+	spinlock_t		lock;
+
+	struct usb_device	*dev;
+	int			pipe;
+	struct scatterlist	*sg;
+	int			nents;
+
+	int			entries;
+	struct urb		**urbs;
+
+	int			count;
+	struct completion	complete;
+};
+
+
 /* we allocate one of these for every device that we remember */
 struct us_data {
 	struct us_data		*next;		 /* next device */
@@ -171,6 +225,7 @@
 	struct urb		*current_urb;	 /* non-int USB requests */
 	struct completion	current_done;	 /* the done flag        */
 	unsigned int		tag;		 /* tag for bulk CBW/CSW */
+	struct usb_sg_request	current_sg;  /* scatter-gather req.  */
 
 	/* the semaphore for sleeping the control thread */
 	struct semaphore	sema;		 /* to sleep thread on   */
Index: linux-2.4.35.4/include/linux/usb.h
===================================================================
--- linux-2.4.35.4.orig/include/linux/usb.h	2007-12-15 05:19:38.750629310 +0100
+++ linux-2.4.35.4/include/linux/usb.h	2007-12-15 05:20:04.740110367 +0100
@@ -483,6 +483,8 @@
 #define URB_NO_INTERRUPT	0x0080	/* HINT: no non-error interrupt needed */
 					/* ... less overhead for QUEUE_BULK */
 #define USB_TIMEOUT_KILLED	0x1000	// only set by HCD!
+#define URB_NO_TRANSFER_DMA_MAP	0x0400	/* urb->transfer_dma valid on submit */
+#define URB_NO_SETUP_DMA_MAP	0x0800	/* urb->setup_dma valid on submit */
 
 struct iso_packet_descriptor
 {