Merge kroah.com:/home/greg/linux/BK/bleeding_edge-2.5

into kroah.com:/home/greg/linux/BK/gregkh-2.5

Documentation/DocBook/kernel-api.tmpl

@@ -299,6 +299,8 @@ KAO -->
     EHCI, OHCI, or UHCI.
     </para>
 !Edrivers/usb/core/hcd.c
+!Edrivers/usb/core/hcd-pci.c
+!Edrivers/usb/core/buffer.c
     </sect1>
 
   </chapter>

drivers/usb/core/Makefile

@@ -2,10 +2,10 @@
 # Makefile for USB Core files and filesystem
 #
 
-export-objs	:= usb.o hcd.o hcd-pci.o urb.o message.o file.o
+export-objs	:= usb.o hcd.o hcd-pci.o urb.o message.o file.o buffer.o
 
 usbcore-objs	:= usb.o usb-debug.o hub.o hcd.o urb.o message.o \
-			config.o file.o
+			config.o file.o buffer.o
 
 ifeq ($(CONFIG_PCI),y)
 	usbcore-objs	+= hcd-pci.o

drivers/usb/core/buffer.c

+/*
+ * DMA memory management for framework level HCD code (hc_driver)
+ *
+ * This implementation plugs in through generic "usb_bus" level methods,
+ * and works with real PCI, or when "pci device == null" makes sense.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+
+
+#ifdef CONFIG_USB_DEBUG
+	#define DEBUG
+#else
+	#undef DEBUG
+#endif
+
+#include <linux/usb.h>
+#include "hcd.h"
+
+
+/*
+ * DMA-Consistent Buffers
+ */
+
+/* FIXME tune these based on pool statistics ... */
+static const size_t	pool_max [HCD_BUFFER_POOLS] = {
+	32,
+	128,
+	512,
+	PAGE_SIZE / 2
+	/* bigger --> allocate pages */
+};
+
+
+/* SETUP primitives */
+
+/**
+ * hcd_buffer_create - initialize buffer pools
+ * @hcd: the bus whose buffer pools are to be initialized
+ *
+ * Call this as part of initializing a host controller that uses the pci dma
+ * memory allocators.  It initializes some pools of dma-consistent memory that
+ * will be shared by all drivers using that controller, or returns a negative
+ * errno value on error.
+ *
+ * Call hcd_buffer_destroy() to clean up after using those pools.
+ */
+int hcd_buffer_create (struct usb_hcd *hcd)
+{
+	char		name [16];
+	int 		i, size;
+
+	for (i = 0; i < HCD_BUFFER_POOLS; i++) { 
+		if (!(size = pool_max [i]))
+			continue;
+		snprintf (name, sizeof name, "buffer-%d", size);
+		hcd->pool [i] = pci_pool_create (name, hcd->pdev,
+				size, size, 0, SLAB_KERNEL);
+		if (!hcd->pool [i]) {
+			hcd_buffer_destroy (hcd);
+			return -ENOMEM;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL (hcd_buffer_create);
+
+
+/**
+ * hcd_buffer_destroy - deallocate buffer pools
+ * @hcd: the bus whose buffer pools are to be destroyed
+ *
+ * This frees the buffer pools created by hcd_buffer_create().
+ */
+void hcd_buffer_destroy (struct usb_hcd *hcd)
+{
+	int		i;
+
+	for (i = 0; i < HCD_BUFFER_POOLS; i++) { 
+		struct pci_pool		*pool = hcd->pool [i];
+		if (pool) {
+			pci_pool_destroy (pool);
+			hcd->pool [i] = 0;
+		}
+	}
+}
+EXPORT_SYMBOL (hcd_buffer_destroy);
+
+
+/* sometimes alloc/free could use kmalloc with SLAB_DMA, for
+ * better sharing and to leverage mm/slab.c intelligence.
+ */
+
+void *hcd_buffer_alloc (
+	struct usb_bus 		*bus,
+	size_t			size,
+	int			mem_flags,
+	dma_addr_t		*dma
+)
+{
+	struct usb_hcd		*hcd = bus->hcpriv;
+	int 			i;
+
+	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
+		if (size <= pool_max [i])
+			return pci_pool_alloc (hcd->pool [i], mem_flags, dma);
+	}
+	return pci_alloc_consistent (hcd->pdev, size, dma);
+}
+
+void hcd_buffer_free (
+	struct usb_bus 		*bus,
+	size_t			size,
+	void 			*addr,
+	dma_addr_t		dma
+)
+{
+	struct usb_hcd		*hcd = bus->hcpriv;
+	int 			i;
+
+	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
+		if (size <= pool_max [i]) {
+			pci_pool_free (hcd->pool [i], addr, dma);
+			return;
+		}
+	}
+	pci_free_consistent (hcd->pdev, size, addr, dma);
+}
+
+
+/*
+ * DMA-Mappings for arbitrary memory buffers
+ */
+
+int hcd_buffer_map (
+	struct usb_bus	*bus,
+	void		*addr,
+	dma_addr_t	*dma,
+	size_t		size,
+	int		direction
+) {
+	struct usb_hcd	*hcd = bus->hcpriv;
+
+	// FIXME pci_map_single() has no standard failure mode!
+	*dma = pci_map_single (hcd->pdev, addr, size,
+			(direction == USB_DIR_IN)
+				? PCI_DMA_FROMDEVICE
+				: PCI_DMA_TODEVICE);
+	return 0;
+}
+
+void hcd_buffer_dmasync (
+	struct usb_bus	*bus,
+	dma_addr_t	dma,
+	size_t		size,
+	int		direction
+) {
+	struct usb_hcd *hcd = bus->hcpriv;
+
+	pci_dma_sync_single (hcd->pdev, dma, size,
+			(direction == USB_DIR_IN)
+				? PCI_DMA_FROMDEVICE
+				: PCI_DMA_TODEVICE);
+}
+
+void hcd_buffer_unmap (
+	struct usb_bus	*bus,
+	dma_addr_t	dma,
+	size_t		size,
+	int		direction
+) {
+	struct usb_hcd *hcd = bus->hcpriv;
+
+	pci_unmap_single (hcd->pdev, dma, size,
+			(direction == USB_DIR_IN)
+				? PCI_DMA_FROMDEVICE
+				: PCI_DMA_TODEVICE);
+}
+
+
+// FIXME DMA-Mappings for struct scatterlist

drivers/usb/core/hcd-pci.c

@@ -130,10 +130,19 @@ int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
 			return retval;
 		}
 	}
-	pci_set_drvdata(dev, hcd);
+	pci_set_drvdata (dev, hcd);
 	hcd->driver = driver;
 	hcd->description = driver->description;
 	hcd->pdev = dev;
+	hcd->self.bus_name = dev->slot_name;
+	hcd->product_desc = dev->name;
+
+	if ((retval = hcd_buffer_create (hcd)) != 0) {
+clean_3:
+		driver->hcd_free (hcd);
+		goto clean_2;
+	}
+
 	info ("%s @ %s, %s", hcd->description,  dev->slot_name, dev->name);
 
 	pci_read_config_byte (dev, PCI_LATENCY_TIMER, &latency);
@@ -154,8 +163,7 @@ int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
 			!= 0) {
 		err ("request interrupt %s failed", bufp);
 		retval = -EBUSY;
-		driver->hcd_free (hcd);
-		goto clean_2;
+		goto clean_3;
 	}
 	hcd->irq = dev->irq;
 
@@ -168,8 +176,6 @@ int usb_hcd_pci_probe (struct pci_dev *dev, const struct pci_device_id *id)
 	usb_bus_init (&hcd->self);
 	hcd->self.op = &usb_hcd_operations;
 	hcd->self.hcpriv = (void *) hcd;
-	hcd->self.bus_name = dev->slot_name;
-	hcd->product_desc = dev->name;
 
 	INIT_LIST_HEAD (&hcd->dev_list);
 
@@ -216,6 +222,7 @@ void usb_hcd_pci_remove (struct pci_dev *dev)
 	usb_disconnect (&hub);
 
 	hcd->driver->stop (hcd);
+	hcd_buffer_destroy (hcd);
 	hcd->state = USB_STATE_HALT;
 
 	free_irq (hcd->irq, hcd);

drivers/usb/core/hcd.c

@@ -454,7 +454,6 @@ static int rh_status_urb (struct usb_hcd *hcd, struct urb *urb)
 	/* rh_timer protected by hcd_data_lock */
 	if (timer_pending (&hcd->rh_timer)
 			|| urb->status != -EINPROGRESS
-			|| !HCD_IS_RUNNING (hcd->state)
 			|| urb->transfer_buffer_length < len) {
 		dbg ("not queuing status urb, stat %d", urb->status);
 		return -EINVAL;
@@ -508,8 +507,12 @@ static void rh_report_status (unsigned long ptr)
 				BUG ();
 			}
 			spin_unlock_irqrestore (&hcd_data_lock, flags);
-		} else
+		} else {
 			spin_unlock_irqrestore (&urb->lock, flags);
+			spin_lock_irqsave (&hcd_data_lock, flags);
+			rh_status_urb (hcd, urb);
+			spin_unlock_irqrestore (&hcd_data_lock, flags);
+		}
 	} else {
 		/* this urb's been unlinked */
 		urb->hcpriv = 0;
@@ -1245,6 +1248,11 @@ struct usb_operations usb_hcd_operations = {
 	.submit_urb =		hcd_submit_urb,
 	.unlink_urb =		hcd_unlink_urb,
 	.deallocate =		hcd_free_dev,
+	.buffer_alloc =		hcd_buffer_alloc,
+	.buffer_free =		hcd_buffer_free,
+	.buffer_map =		hcd_buffer_map,
+	.buffer_dmasync =	hcd_buffer_dmasync,
+	.buffer_unmap =		hcd_buffer_unmap,
 };
 EXPORT_SYMBOL (usb_hcd_operations);
 

drivers/usb/core/hcd.h

@@ -58,6 +58,9 @@ struct usb_hcd {	/* usb_bus.hcpriv points to this */
 	atomic_t		resume_count;	/* multiple resumes issue */
 #endif
 
+#define HCD_BUFFER_POOLS	4
+	struct pci_pool		*pool [HCD_BUFFER_POOLS];
+
 	int			state;
 #	define	__ACTIVE		0x01
 #	define	__SLEEPY		0x02
@@ -109,6 +112,25 @@ struct usb_operations {
 	int (*get_frame_number) (struct usb_device *usb_dev);
 	int (*submit_urb) (struct urb *urb, int mem_flags);
 	int (*unlink_urb) (struct urb *urb);
+
+	/* allocate dma-consistent buffer for URB_DMA_NOMAPPING */
+	void *(*buffer_alloc)(struct usb_bus *bus, size_t size,
+			int mem_flags,
+			dma_addr_t *dma);
+	void (*buffer_free)(struct usb_bus *bus, size_t size,
+			void *addr, dma_addr_t dma);
+
+	int (*buffer_map) (struct usb_bus *bus,
+		void *addr, dma_addr_t *dma,
+		size_t size, int direction);
+	void (*buffer_dmasync) (struct usb_bus *bus,
+		dma_addr_t dma,
+		size_t size, int direction);
+	void (*buffer_unmap) (struct usb_bus *bus,
+		dma_addr_t dma,
+		size_t size, int direction);
+
+	// FIXME  also: buffer_sg_map (), buffer_sg_unmap ()
 };
 
 /* each driver provides one of these, and hardware init support */
@@ -181,6 +203,25 @@ extern int usb_hcd_pci_resume (struct pci_dev *dev);
 
 #endif /* CONFIG_PCI */
 
+/* pci-ish (pdev null is ok) buffer alloc/mapping support */
+int hcd_buffer_create (struct usb_hcd *hcd);
+void hcd_buffer_destroy (struct usb_hcd *hcd);
+
+void *hcd_buffer_alloc (struct usb_bus *bus, size_t size,
+	int mem_flags, dma_addr_t *dma);
+void hcd_buffer_free (struct usb_bus *bus, size_t size,
+	void *addr, dma_addr_t dma);
+
+int hcd_buffer_map (struct usb_bus *bus,
+	void *addr, dma_addr_t *dma,
+	size_t size, int direction);
+void hcd_buffer_dmasync (struct usb_bus *bus,
+	dma_addr_t dma,
+	size_t size, int direction);
+void hcd_buffer_unmap (struct usb_bus *bus,
+	dma_addr_t dma,
+	size_t size, int direction);
+
 /* generic bus glue, needed for host controllers that don't use PCI */
 extern struct usb_operations usb_hcd_operations;
 extern void usb_hcd_irq (int irq, void *__hcd, struct pt_regs *r);

drivers/usb/core/usb.c

@@ -863,9 +863,11 @@ static ssize_t show_product (struct device *dev, char *buf, size_t count, loff_t
 		return 0;
 	udev = to_usb_device (dev);
 
-	len = usb_string(udev, udev->descriptor.iProduct, buf, PAGE_SIZE); 
+	len = usb_string(udev, udev->descriptor.iProduct, buf, PAGE_SIZE);
+	if (len < 0)
+		return 0;
 	buf[len] = '\n';
-	buf[len+1] = 0x00;
+	buf[len+1] = 0;
 	return len+1;
 }
 static DEVICE_ATTR(product,"product",S_IRUGO,show_product,NULL);
@@ -881,9 +883,11 @@ show_manufacturer (struct device *dev, char *buf, size_t count, loff_t off)
 		return 0;
 	udev = to_usb_device (dev);
 
-	len = usb_string(udev, udev->descriptor.iManufacturer, buf, PAGE_SIZE); 
+	len = usb_string(udev, udev->descriptor.iManufacturer, buf, PAGE_SIZE);
+	if (len < 0)
+		return 0;
 	buf[len] = '\n';
-	buf[len+1] = 0x00;
+	buf[len+1] = 0;
 	return len+1;
 }
 static DEVICE_ATTR(manufacturer,"manufacturer",S_IRUGO,show_manufacturer,NULL);
@@ -899,9 +903,11 @@ show_serial (struct device *dev, char *buf, size_t count, loff_t off)
 		return 0;
 	udev = to_usb_device (dev);
 
-	len = usb_string(udev, udev->descriptor.iSerialNumber, buf, PAGE_SIZE); 
+	len = usb_string(udev, udev->descriptor.iSerialNumber, buf, PAGE_SIZE);
+	if (len < 0)
+		return 0;
 	buf[len] = '\n';
-	buf[len+1] = 0x00;
+	buf[len+1] = 0;
 	return len+1;
 }
 static DEVICE_ATTR(serial,"serial",S_IRUGO,show_serial,NULL);
@@ -918,13 +924,13 @@ static void usb_find_drivers(struct usb_device *dev)
 	unsigned claimed = 0;
 
 	/* FIXME should get called for each new configuration not just the
-	 * first one for a device. switching configs (or altesettings) should
+	 * first one for a device. switching configs (or altsettings) should
 	 * undo driverfs and HCD state for the previous interfaces.
 	 */
 	for (ifnum = 0; ifnum < dev->actconfig->bNumInterfaces; ifnum++) {
 		struct usb_interface *interface = &dev->actconfig->interface[ifnum];
 		struct usb_interface_descriptor *desc = interface->altsetting;
-		
+
 		/* register this interface with driverfs */
 		interface->dev.parent = &dev->dev;
 		interface->dev.bus = &usb_bus_type;
@@ -1455,6 +1461,152 @@ int usb_new_device(struct usb_device *dev)
 }
 
 
+/**
+ * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_DMA_MAP
+ * @dev: device the buffer will be used with
+ * @size: requested buffer size
+ * @mem_flags: affect whether allocation may block
+ * @dma: used to return DMA address of buffer
+ *
+ * Return value is either null (indicating no buffer could be allocated), or
+ * the cpu-space pointer to a buffer that may be used to perform DMA to the
+ * specified device.  Such cpu-space buffers are returned along with the DMA
+ * address (through the pointer provided).
+ *
+ * These buffers are used with URB_NO_DMA_MAP set in urb->transfer_flags to
+ * avoid behaviors like using "DMA bounce buffers", or tying down I/O mapping
+ * hardware for long idle periods.  The implementation varies between
+ * platforms, depending on details of how DMA will work to this device.
+ *
+ * When the buffer is no longer used, free it with usb_buffer_free().
+ */
+void *usb_buffer_alloc (
+	struct usb_device *dev,
+	size_t size,
+	int mem_flags,
+	dma_addr_t *dma
+)
+{
+	if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_alloc)
+		return 0;
+	return dev->bus->op->buffer_alloc (dev->bus, size, mem_flags, dma);
+}
+
+/**
+ * usb_buffer_free - free memory allocated with usb_buffer_alloc()
+ * @dev: device the buffer was used with
+ * @size: requested buffer size
+ * @addr: CPU address of buffer
+ * @dma: DMA address of buffer
+ *
+ * This reclaims an I/O buffer, letting it be reused.  The memory must have
+ * been allocated using usb_buffer_alloc(), and the parameters must match
+ * those provided in that allocation request. 
+ */
+void usb_buffer_free (
+	struct usb_device *dev,
+	size_t size,
+	void *addr,
+	dma_addr_t dma
+)
+{
+	if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_free)
+	    	return;
+	dev->bus->op->buffer_free (dev->bus, size, addr, dma);
+}
+
+/**
+ * usb_buffer_map - create DMA mapping(s) for an urb
+ * @urb: urb whose transfer_buffer will be mapped
+ *
+ * Return value is either null (indicating no buffer could be mapped), or
+ * the parameter.  URB_NO_DMA_MAP is added to urb->transfer_flags if the
+ * operation succeeds.
+ *
+ * This call would normally be used for an urb which is reused, perhaps
+ * as the target of a large periodic transfer, with usb_buffer_dmasync()
+ * calls to synchronize memory and dma state.  It may not be used for
+ * control requests.
+ *
+ * Reverse the effect of this call with usb_buffer_unmap().
+ */
+struct urb *usb_buffer_map (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct usb_operations	*op;
+
+	if (!urb
+			|| usb_pipecontrol (urb->pipe)
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(op = bus->op)
+			|| !op->buffer_map)
+		return 0;
+
+	if (op->buffer_map (bus,
+			urb->transfer_buffer,
+			&urb->transfer_dma,
+			urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? USB_DIR_IN
+				: USB_DIR_OUT))
+		return 0;
+	urb->transfer_flags |= URB_NO_DMA_MAP;
+	return urb;
+}
+
+/**
+ * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
+ * @urb: urb whose transfer_buffer will be synchronized
+ */
+void usb_buffer_dmasync (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct usb_operations	*op;
+
+	if (!urb
+			|| !(urb->transfer_flags & URB_NO_DMA_MAP)
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(op = bus->op)
+			|| !op->buffer_dmasync)
+		return;
+
+	op->buffer_dmasync (bus,
+			urb->transfer_dma,
+			urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? USB_DIR_IN
+				: USB_DIR_OUT);
+}
+
+/**
+ * usb_buffer_unmap - free DMA mapping(s) for an urb
+ * @urb: urb whose transfer_buffer will be unmapped
+ *
+ * Reverses the effect of usb_buffer_map().
+ */
+void usb_buffer_unmap (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct usb_operations	*op;
+
+	if (!urb
+			|| !(urb->transfer_flags & URB_NO_DMA_MAP)
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(op = bus->op)
+			|| !op->buffer_unmap)
+		return;
+
+	op->buffer_unmap (bus,
+			urb->transfer_dma,
+			urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? USB_DIR_IN
+				: USB_DIR_OUT);
+}
+
 #ifdef CONFIG_PROC_FS
 struct list_head *usb_driver_get_list(void)
 {
@@ -1534,4 +1686,11 @@ EXPORT_SYMBOL(__usb_get_extra_descriptor);
 
 EXPORT_SYMBOL(usb_get_current_frame_number);
 
+EXPORT_SYMBOL (usb_buffer_alloc);
+EXPORT_SYMBOL (usb_buffer_free);
+
+EXPORT_SYMBOL (usb_buffer_map);
+EXPORT_SYMBOL (usb_buffer_dmasync);
+EXPORT_SYMBOL (usb_buffer_unmap);
+
 MODULE_LICENSE("GPL");

drivers/usb/host/ehci-dbg.c

 /*
- * Copyright (c) 2001 by David Brownell
+ * 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
@@ -175,3 +175,215 @@ dbg_qh (char *label, struct ehci_hcd *ehci, struct ehci_qh *qh) {}
 		(status & PORT_CONNECT) ? " CONNECT" : "" \
 	    )
 
+#ifdef DEBUG
+
+#define speed_char(info1) ({ char tmp; \
+		switch (info1 & (3 << 12)) { \
+		case 0 << 12: tmp = 'f'; break; \
+		case 1 << 12: tmp = 'l'; break; \
+		case 2 << 12: tmp = 'h'; break; \
+		default: tmp = '?'; break; \
+		}; tmp; })
+
+static ssize_t
+show_async (struct device *dev, char *buf, size_t count, loff_t off)
+{
+	struct pci_dev		*pdev;
+	struct ehci_hcd		*ehci;
+	unsigned long		flags;
+	unsigned		temp, size;
+	char			*next;
+	struct ehci_qh		*qh;
+
+	if (off != 0)
+		return 0;
+
+	pdev = container_of (dev, struct pci_dev, dev);
+	ehci = container_of (pci_get_drvdata (pdev), struct ehci_hcd, hcd);
+	next = buf;
+	size = count;
+
+	/* dumps a snapshot of the async schedule.
+	 * usually empty except for long-term bulk reads, or head.
+	 * one QH per line, and TDs we know about
+	 */
+	spin_lock_irqsave (&ehci->lock, flags);
+	if (ehci->async) {
+		qh = ehci->async;
+		do {
+			u32			scratch;
+			struct list_head	*entry;
+			struct ehci_qtd		*td;
+
+			scratch = cpu_to_le32p (&qh->hw_info1);
+			temp = snprintf (next, size, "qh %p dev%d %cs ep%d",
+					qh, scratch & 0x007f,
+					speed_char (scratch),
+					(scratch >> 8) & 0x000f);
+			size -= temp;
+			next += temp;
+
+			list_for_each (entry, &qh->qtd_list) {
+				td = list_entry (entry, struct ehci_qtd,
+						qtd_list);
+				scratch = cpu_to_le32p (&td->hw_token);
+				temp = snprintf (next, size,
+						", td %p len=%d %s",
+						td, scratch >> 16,
+						({ char *tmp;
+						 switch ((scratch>>8)&0x03) {
+						 case 0: tmp = "out"; break;
+						 case 1: tmp = "in"; break;
+						 case 2: tmp = "setup"; break;
+						 default: tmp = "?"; break;
+						 } tmp;})
+						);
+				size -= temp;
+				next += temp;
+			}
+
+			temp = snprintf (next, size, "\n");
+			size -= temp;
+			next += temp;
+
+		} while ((qh = qh->qh_next.qh) != ehci->async);
+	}
+	spin_unlock_irqrestore (&ehci->lock, flags);
+
+	return count - size;
+}
+static DEVICE_ATTR (async, "sched-async", S_IRUSR, show_async, NULL);
+
+#define DBG_SCHED_LIMIT 64
+
+static ssize_t
+show_periodic (struct device *dev, char *buf, size_t count, loff_t off)
+{
+	struct pci_dev		*pdev;
+	struct ehci_hcd		*ehci;
+	unsigned long		flags;
+	union ehci_shadow	p, *seen;
+	unsigned		temp, size, seen_count;
+	char			*next;
+	unsigned		i, tag;
+
+	if (off != 0)
+		return 0;
+	if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, SLAB_ATOMIC)))
+		return 0;
+	seen_count = 0;
+
+	pdev = container_of (dev, struct pci_dev, dev);
+	ehci = container_of (pci_get_drvdata (pdev), struct ehci_hcd, hcd);
+	next = buf;
+	size = count;
+
+	temp = snprintf (next, size, "size = %d\n", ehci->periodic_size);
+	size -= temp;
+	next += temp;
+
+	/* dump a snapshot of the periodic schedule.
+	 * iso changes, interrupt usually doesn't.
+	 */
+	spin_lock_irqsave (&ehci->lock, flags);
+	for (i = 0; i < ehci->periodic_size; i++) {
+		p = ehci->pshadow [i];
+		if (!p.ptr)
+			continue;
+		tag = Q_NEXT_TYPE (ehci->periodic [i]);
+
+		temp = snprintf (next, size, "%4d: ", i);
+		size -= temp;
+		next += temp;
+
+		do {
+			switch (tag) {
+			case Q_TYPE_QH:
+				temp = snprintf (next, size, " intr-%d %p",
+						p.qh->period, p.qh);
+				size -= temp;
+				next += temp;
+				for (temp = 0; temp < seen_count; temp++) {
+					if (seen [temp].ptr == p.ptr)
+						break;
+				}
+				/* show more info the first time around */
+				if (temp == seen_count) {
+					u32	scratch = cpu_to_le32p (
+							&p.qh->hw_info1);
+
+					temp = snprintf (next, size,
+						" (%cs dev%d ep%d)",
+						speed_char (scratch),
+						scratch & 0x007f,
+						(scratch >> 8) & 0x000f);
+
+					/* FIXME TDs too */
+
+					if (seen_count < DBG_SCHED_LIMIT)
+						seen [seen_count++].qh = p.qh;
+				} else
+					temp = 0;
+				tag = Q_NEXT_TYPE (p.qh->hw_next);
+				p = p.qh->qh_next;
+				break;
+			case Q_TYPE_FSTN:
+				temp = snprintf (next, size,
+					" fstn-%8x/%p", p.fstn->hw_prev,
+					p.fstn);
+				tag = Q_NEXT_TYPE (p.fstn->hw_next);
+				p = p.fstn->fstn_next;
+				break;
+			case Q_TYPE_ITD:
+				temp = snprintf (next, size,
+					" itd/%p", p.itd);
+				tag = Q_NEXT_TYPE (p.itd->hw_next);
+				p = p.itd->itd_next;
+				break;
+			case Q_TYPE_SITD:
+				temp = snprintf (next, size,
+					" sitd/%p", p.sitd);
+				tag = Q_NEXT_TYPE (p.sitd->hw_next);
+				p = p.sitd->sitd_next;
+				break;
+			}
+			size -= temp;
+			next += temp;
+		} while (p.ptr);
+
+		temp = snprintf (next, size, "\n");
+		size -= temp;
+		next += temp;
+	}
+	spin_unlock_irqrestore (&ehci->lock, flags);
+	kfree (seen);
+
+	return count - size;
+}
+static DEVICE_ATTR (periodic, "sched-periodic", S_IRUSR, show_periodic, NULL);
+
+#undef DBG_SCHED_LIMIT
+
+static inline void create_debug_files (struct ehci_hcd *bus)
+{
+	device_create_file (&bus->hcd.pdev->dev, &dev_attr_async);
+	device_create_file (&bus->hcd.pdev->dev, &dev_attr_periodic);
+}
+
+static inline void remove_debug_files (struct ehci_hcd *bus)
+{
+	device_remove_file (&bus->hcd.pdev->dev, &dev_attr_async);
+	device_remove_file (&bus->hcd.pdev->dev, &dev_attr_periodic);
+}
+
+#else /* DEBUG */
+
+static inline void create_debug_files (struct ehci_hcd *bus)
+{
+}
+
+static inline void remove_debug_files (struct ehci_hcd *bus)
+{
+}
+
+#endif /* DEBUG */

drivers/usb/host/ehci-hcd.c

@@ -65,6 +65,8 @@
  *
  * HISTORY:
  *
+ * 2002-08-06	Handling for bulk and interrupt transfers is mostly shared;
+ *	only scheduling is different, no arbitrary limitations.
  * 2002-07-25	Sanity check PCI reads, mostly for better cardbus support,
  * 	clean up HC run state handshaking.
  * 2002-05-24	Preliminary FS/LS interrupts, using scheduling shortcuts
@@ -85,7 +87,7 @@
  * 2001-June	Works with usb-storage and NEC EHCI on 2.4
  */
 
-#define DRIVER_VERSION "2002-Jul-25"
+#define DRIVER_VERSION "2002-Aug-06"
 #define DRIVER_AUTHOR "David Brownell"
 #define DRIVER_DESC "USB 2.0 'Enhanced' Host Controller (EHCI) Driver"
 
@@ -93,6 +95,8 @@
 // #define EHCI_VERBOSE_DEBUG
 // #define have_split_iso
 
+#define INTR_AUTOMAGIC		/* to be removed later in 2.5 */
+
 /* magic numbers that can affect system performance */
 #define	EHCI_TUNE_CERR		3	/* 0-3 qtd retries; 0 == don't stop */
 #define	EHCI_TUNE_RL_HS		0	/* nak throttle; see 4.9 */
@@ -376,6 +380,8 @@ static int ehci_start (struct usb_hcd *hcd)
 		return -ENOMEM;
 	}
 
+	create_debug_files (ehci);
+
 	/*
 	 * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
 	 * are explicitly handed to companion controller(s), so no TT is
@@ -429,6 +435,8 @@ static void ehci_stop (struct usb_hcd *hcd)
 		ehci_ready (ehci);
 	ehci_reset (ehci);
 
+	remove_debug_files (ehci);
+
 	/* root hub is shut down separately (first, when possible) */
 	tasklet_disable (&ehci->tasklet);
 	ehci_tasklet ((unsigned long) ehci);
@@ -614,7 +622,8 @@ static void ehci_irq (struct usb_hcd *hcd)
  *
  * hcd-specific init for hcpriv hasn't been done yet
  *
- * NOTE:  EHCI queues control and bulk requests transparently, like OHCI.
+ * NOTE:  control, bulk, and interrupt share the same code to append TDs
+ * to a (possibly active) QH, and the same QH scanning code.
  */
 static int ehci_urb_enqueue (
 	struct usb_hcd	*hcd,
@@ -626,10 +635,11 @@ static int ehci_urb_enqueue (
 
 	urb->transfer_flags &= ~EHCI_STATE_UNLINK;
 	INIT_LIST_HEAD (&qtd_list);
-	switch (usb_pipetype (urb->pipe)) {
 
-	case PIPE_CONTROL:
-	case PIPE_BULK:
+	switch (usb_pipetype (urb->pipe)) {
+	// case PIPE_CONTROL:
+	// case PIPE_BULK:
+	default:
 		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
 			return -ENOMEM;
 		return submit_async (ehci, urb, &qtd_list, mem_flags);
@@ -649,9 +659,6 @@ static int ehci_urb_enqueue (
 		dbg ("no split iso support yet");
 		return -ENOSYS;
 #endif /* have_split_iso */
-
-	default:	/* can't happen */
-		return -ENOSYS;
 	}
 }
 
@@ -665,15 +672,16 @@ static int ehci_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
 	struct ehci_qh		*qh = (struct ehci_qh *) urb->hcpriv;
 	unsigned long		flags;
 
-	dbg ("%s urb_dequeue %p qh state %d",
-		hcd->self.bus_name, urb, qh->qh_state);
+	dbg ("%s urb_dequeue %p qh %p state %d",
+		hcd->self.bus_name, urb, qh, qh->qh_state);
 
 	switch (usb_pipetype (urb->pipe)) {
-	case PIPE_CONTROL:
-	case PIPE_BULK:
+	// case PIPE_CONTROL:
+	// case PIPE_BULK:
+	default:
 		spin_lock_irqsave (&ehci->lock, flags);
 		if (ehci->reclaim) {
-dbg ("dq: reclaim busy, %s", RUN_CONTEXT);
+			dbg ("dq: reclaim busy, %s", RUN_CONTEXT);
 			if (in_interrupt ()) {
 				spin_unlock_irqrestore (&ehci->lock, flags);
 				return -EAGAIN;
@@ -683,28 +691,43 @@ dbg ("dq: reclaim busy, %s", RUN_CONTEXT);
 					&& ehci->hcd.state != USB_STATE_HALT
 					) {
 				spin_unlock_irqrestore (&ehci->lock, flags);
-// yeech ... this could spin for up to two frames!
-dbg ("wait for dequeue: state %d, reclaim %p, hcd state %d",
-    qh->qh_state, ehci->reclaim, ehci->hcd.state
-);
-				udelay (100);
+				/* let pending unlinks complete */
+				wait_ms (1);
 				spin_lock_irqsave (&ehci->lock, flags);
 			}
 		}
 		if (qh->qh_state == QH_STATE_LINKED)
 			start_unlink_async (ehci, qh);
 		spin_unlock_irqrestore (&ehci->lock, flags);
-		return 0;
+		break;
 
 	case PIPE_INTERRUPT:
-		intr_deschedule (ehci, urb->start_frame, qh,
-			(urb->dev->speed == USB_SPEED_HIGH)
-			    ? urb->interval
-			    : (urb->interval << 3));
-		if (ehci->hcd.state == USB_STATE_HALT)
-			urb->status = -ESHUTDOWN;
-		qh_completions (ehci, qh, 1);
-		return 0;
+		if (qh->qh_state == QH_STATE_LINKED) {
+			/* messy, can spin or block a microframe ... */
+			intr_deschedule (ehci, qh, 1);
+			/* qh_state == IDLE */
+		}
+		qh_completions (ehci, qh);
+
+		/* reschedule QH iff another request is queued */
+		if (!list_empty (&qh->qtd_list)
+				&& HCD_IS_RUNNING (ehci->hcd.state)) {
+			int status;
+
+			spin_lock_irqsave (&ehci->lock, flags);
+			status = qh_schedule (ehci, qh);
+			spin_unlock_irqrestore (&ehci->lock, flags);
+
+			if (status != 0) {
+				// shouldn't happen often, but ...
+				// FIXME kill those tds' urbs
+				err ("can't reschedule qh %p, err %d",
+					qh, status);
+			}
+			return status;
+		}
+
+		break;
 
 	case PIPE_ISOCHRONOUS:
 		// itd or sitd ...
@@ -712,9 +735,9 @@ dbg ("wait for dequeue: state %d, reclaim %p, hcd state %d",
 		// wait till next completion, do it then.
 		// completion irqs can wait up to 1024 msec,
 		urb->transfer_flags |= EHCI_STATE_UNLINK;
-		return 0;
+		break;
 	}
-	return -EINVAL;
+	return 0;
 }
 
 /*-------------------------------------------------------------------------*/
@@ -728,6 +751,7 @@ static void ehci_free_config (struct usb_hcd *hcd, struct usb_device *udev)
 	int			i;
 	unsigned long		flags;
 
+	/* ASSERT:  no requests/urbs are still linked (so no TDs) */
 	/* ASSERT:  nobody can be submitting urbs for this any more */
 
 	dbg ("%s: free_config devnum %d", hcd->self.bus_name, udev->devnum);
@@ -736,34 +760,57 @@ static void ehci_free_config (struct usb_hcd *hcd, struct usb_device *udev)
 	for (i = 0; i < 32; i++) {
 		if (dev->ep [i]) {
 			struct ehci_qh		*qh;
+			char			*why;
 
 			/* dev->ep never has ITDs or SITDs */
 			qh = (struct ehci_qh *) dev->ep [i];
-			vdbg ("free_config, ep 0x%02x qh %p", i, qh);
-			if (!list_empty (&qh->qtd_list)) {
-				dbg ("ep 0x%02x qh %p not empty!", i, qh);
+
+			/* detect/report non-recoverable errors */
+			if (in_interrupt ()) 
+				why = "disconnect() didn't";
+			else if ((qh->hw_info2 & cpu_to_le32 (0xffff)) != 0
+					&& qh->qh_state != QH_STATE_IDLE)
+				why = "(active periodic)";
+			else
+				why = 0;
+			if (why) {
+				err ("dev %s-%s ep %d-%s error: %s",
+					hcd->self.bus_name, udev->devpath,
+					i & 0xf, (i & 0x10) ? "IN" : "OUT",
+					why);
 				BUG ();
 			}
-			dev->ep [i] = 0;
 
-			/* wait_ms() won't spin here -- we're a thread */
+			dev->ep [i] = 0;
+			if (qh->qh_state == QH_STATE_IDLE)
+				goto idle;
+			dbg ("free_config, async ep 0x%02x qh %p", i, qh);
+
+			/* scan_async() empties the ring as it does its work,
+			 * using IAA, but doesn't (yet?) turn it off.  if it
+			 * doesn't empty this qh, likely it's the last entry.
+			 */
 			while (qh->qh_state == QH_STATE_LINKED
 					&& ehci->reclaim
 					&& ehci->hcd.state != USB_STATE_HALT
 					) {
 				spin_unlock_irqrestore (&ehci->lock, flags);
+				/* wait_ms() won't spin, we're a thread;
+				 * and we know IRQ+tasklet can progress
+				 */
 				wait_ms (1);
 				spin_lock_irqsave (&ehci->lock, flags);
 			}
-			if (qh->qh_state == QH_STATE_LINKED) {
+			if (qh->qh_state == QH_STATE_LINKED)
 				start_unlink_async (ehci, qh);
-				while (qh->qh_state != QH_STATE_IDLE) {
-					spin_unlock_irqrestore (&ehci->lock,
-						flags);
-					wait_ms (1);
-					spin_lock_irqsave (&ehci->lock, flags);
-				}
+			while (qh->qh_state != QH_STATE_IDLE
+					&& ehci->hcd.state != USB_STATE_HALT) {
+				spin_unlock_irqrestore (&ehci->lock,
+					flags);
+				wait_ms (1);
+				spin_lock_irqsave (&ehci->lock, flags);
 			}
+idle:
 			qh_put (ehci, qh);
 		}
 	}

drivers/usb/host/ehci.h

@@ -50,7 +50,7 @@ struct ehci_hcd {			/* one per controller */
 
 	union ehci_shadow	*pshadow;	/* mirror hw periodic table */
 	int			next_uframe;	/* scan periodic, start here */
-	unsigned		periodic_urbs;	/* how many urbs scheduled? */
+	unsigned		periodic_sched;	/* periodic activity count */
 
 	/* deferred work from IRQ, etc */
 	struct tasklet_struct	tasklet;
@@ -72,7 +72,7 @@ struct ehci_hcd {			/* one per controller */
 };
 
 /* unwrap an HCD pointer to get an EHCI_HCD pointer */ 
-#define hcd_to_ehci(hcd_ptr) list_entry(hcd_ptr, struct ehci_hcd, hcd)
+#define hcd_to_ehci(hcd_ptr) container_of(hcd_ptr, struct ehci_hcd, hcd)
 
 /* NOTE:  urb->transfer_flags expected to not use this bit !!! */
 #define EHCI_STATE_UNLINK	0x8000		/* urb being unlinked */
@@ -287,12 +287,20 @@ struct ehci_qh {
 	struct list_head	qtd_list;	/* sw qtd list */
 
 	atomic_t		refcount;
-	unsigned short		usecs;		/* intr bandwidth */
-	unsigned short		c_usecs;	/* ... split completion bw */
-	short			qh_state;
+
+	u8			qh_state;
 #define	QH_STATE_LINKED		1		/* HC sees this */
 #define	QH_STATE_UNLINK		2		/* HC may still see this */
 #define	QH_STATE_IDLE		3		/* HC doesn't see this */
+
+	/* periodic schedule info */
+	u8			usecs;		/* intr bandwidth */
+	u8			gap_uf;		/* uframes split/csplit gap */
+	u8			c_usecs;	/* ... split completion bw */
+	unsigned short		period;		/* polling interval */
+	unsigned short		start;		/* where polling starts */
+#define NO_FRAME ((unsigned short)~0)			/* pick new start */
+
 } __attribute__ ((aligned (32)));
 
 /*-------------------------------------------------------------------------*/

drivers/usb/host/ohci-q.c

@@ -938,7 +938,7 @@ static void finish_unlinks (struct ohci_hcd *ohci, u16 tick)
 		/* ED's now officially unlinked, hc doesn't see */
 		ed->state = ED_IDLE;
 		ed->hwINFO &= ~ED_SKIP;
-		ed->hwHeadP &= ~cpu_to_le32 (ED_H);
+		ed->hwHeadP &= ~ED_H;
 		ed->hwNextED = 0;
 
 		/* but if there's work queued, reschedule */

drivers/usb/net/cdc-ether.c

-// Portions of this file taken from 
+// Portions of this file taken from
 // Petko Manolov - Petkan (petkan@dce.bg)
 // from his driver pegasus.c
 
@@ -1170,23 +1170,20 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 	if (rc)	{
 		// Nope we couldn't find one we liked.
 		// This device was not meant for us to control.
-		kfree( ether_dev );
-		return	NULL;
+		goto error_all;
 	}
 
-	// Now that we FOUND a configuration. let's try to make the 
+	// Now that we FOUND a configuration. let's try to make the
 	// device go into it.
 	if ( usb_set_configuration( usb, ether_dev->bConfigurationValue ) ) {
 		err("usb_set_configuration() failed");
-		kfree( ether_dev );
-		return NULL;
+		goto error_all;
 	}
 
 	// Now set the communication interface up as required.
 	if (usb_set_interface(usb, ether_dev->comm_bInterfaceNumber, ether_dev->comm_bAlternateSetting)) {
 		err("usb_set_interface() failed");
-		kfree( ether_dev );
-		return NULL;
+		goto error_all;
 	}
 
 	// Only turn traffic on right now if we must...
@@ -1194,23 +1191,21 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 		// We found an alternate setting for the data
 		// interface that allows us to turn off traffic.
 		// We should use it.
-		if (usb_set_interface( usb, 
-		                       ether_dev->data_bInterfaceNumber, 
+		if (usb_set_interface( usb,
+		                       ether_dev->data_bInterfaceNumber,
 		                       ether_dev->data_bAlternateSetting_without_traffic)) {
 			err("usb_set_interface() failed");
-			kfree( ether_dev );
-			return NULL;
+			goto error_all;
 		}
 	} else	{
 		// We didn't find an alternate setting for the data
 		// interface that would let us turn off traffic.
 		// Oh well, let's go ahead and do what we must...
-		if (usb_set_interface( usb, 
-		                       ether_dev->data_bInterfaceNumber, 
+		if (usb_set_interface( usb,
+		                       ether_dev->data_bInterfaceNumber,
 		                       ether_dev->data_bAlternateSetting_with_traffic)) {
 			err("usb_set_interface() failed");
-			kfree( ether_dev );
-			return NULL;
+			goto error_all;
 		}
 	}
 
@@ -1220,8 +1215,7 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 		// Hmm...  The kernel is not sharing today...
 		// Fine, we didn't want it anyway...
 		err( "Unable to initialize ethernet device" );
-		kfree( ether_dev );
-		return	NULL;
+		goto error_all;
 	}
 
 	// Now that we have an ethernet device, let's set it up
@@ -1241,7 +1235,7 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 	// We'll keep track of this information for later...
 	ether_dev->usb = usb;
 	ether_dev->net = net;
-	
+
 	// and don't forget the MAC address.
 	set_ethernet_addr( ether_dev );
 
@@ -1249,12 +1243,12 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 	log_device_info( ether_dev );
 
 	// I claim this interface to be a CDC Ethernet Networking device
-	usb_driver_claim_interface( &CDCEther_driver, 
-	                            &(usb->config[ether_dev->configuration_num].interface[ether_dev->comm_interface]), 
+	usb_driver_claim_interface( &CDCEther_driver,
+	                            &(usb->config[ether_dev->configuration_num].interface[ether_dev->comm_interface]),
 	                            ether_dev );
 	// I claim this interface to be a CDC Ethernet Networking device
-	usb_driver_claim_interface( &CDCEther_driver, 
-	                            &(usb->config[ether_dev->configuration_num].interface[ether_dev->data_interface]), 
+	usb_driver_claim_interface( &CDCEther_driver,
+	                            &(usb->config[ether_dev->configuration_num].interface[ether_dev->data_interface]),
 	                            ether_dev );
 
 	// Does this REALLY do anything???
@@ -1265,6 +1259,14 @@ static void * CDCEther_probe( struct usb_device *usb, unsigned int ifnum,
 
 	// Okay, we are finally done...
 	return NULL;
+
+	// bailing out with our tail between our knees
+error_all:
+	usb_free_urb(ether_dev->tx_urb);
+	usb_free_urb(ether_dev->rx_urb);
+	usb_free_urb(ether_dev->intr_urb);
+	kfree( ether_dev );
+	return	NULL;
 }
 
 

drivers/usb/storage/scsiglue.c

@@ -147,7 +147,8 @@ static int queuecommand( Scsi_Cmnd *srb , void (*done)(Scsi_Cmnd *))
 	srb->host_scribble = (unsigned char *)us;
 
 	/* enqueue the command */
-	BUG_ON(atomic_read(&us->sm_state) != US_STATE_IDLE || us->srb != NULL);
+	BUG_ON(atomic_read(&us->sm_state) != US_STATE_IDLE);
+	BUG_ON(us->srb != NULL);
 	srb->scsi_done = done;
 	us->srb = srb;
 

include/linux/usb.h

@@ -734,6 +734,7 @@ extern void usb_deregister_dev(int num_minors, int start_minor);
  */
 #define URB_SHORT_NOT_OK	0x0001	/* report short reads as errors */
 #define USB_ISO_ASAP		0x0002	/* iso-only, urb->start_frame ignored */
+#define URB_NO_DMA_MAP		0x0004	/* urb->*_dma are valid on submit */
 #define USB_ASYNC_UNLINK	0x0008	/* usb_unlink_urb() returns asap */
 #define USB_NO_FSBR		0x0020	/* UHCI-specific */
 #define USB_ZERO_PACKET		0x0040	/* Finish bulk OUTs with short packet */
@@ -771,11 +772,15 @@ typedef void (*usb_complete_t)(struct urb *);
  * @transfer_flags: A variety of flags may be used to affect how URB
  *	submission, unlinking, or operation are handled.  Different
  *	kinds of URB can use different flags.
- * @transfer_buffer: For non-iso transfers, this identifies the buffer
- *	to (or from) which the I/O request will be performed.  This
- *	buffer must be suitable for DMA; allocate it with kmalloc()
+ * @transfer_buffer:  This identifies the buffer to (or from) which
+ * 	the I/O request will be performed (unless URB_NO_DMA_MAP is set).
+ *	This buffer must be suitable for DMA; allocate it with kmalloc()
  *	or equivalent.  For transfers to "in" endpoints, contents of
- *	this buffer will be modified.
+ *	this buffer will be modified.  This buffer is used for data
+ *	phases of control transfers.
+ * @transfer_dma: When transfer_flags includes URB_NO_DMA_MAP, the device
+ * 	driver is saying that it provided this DMA address, which the host
+ * 	controller driver should use instead of the transfer_buffer.
  * @transfer_buffer_length: How big is transfer_buffer.  The transfer may
  *	be broken up into chunks according to the current maximum packet
  *	size for the endpoint, which is a function of the configuration
@@ -789,6 +794,11 @@ typedef void (*usb_complete_t)(struct urb *);
  * @setup_packet: Only used for control transfers, this points to eight bytes
  *	of setup data.  Control transfers always start by sending this data
  *	to the device.  Then transfer_buffer is read or written, if needed.
+ *	(Not used when URB_NO_DMA_MAP is set.)
+ * @setup_dma: For control transfers with URB_NO_DMA_MAP set, the device
+ * 	driver has provided this DMA address for the setup packet.  The
+ * 	host controller driver should use instead of setup_buffer.
+ * 	If there is a data phase, its buffer is identified by transfer_dma.
  * @start_frame: Returns the initial frame for interrupt or isochronous
  *	transfers.
  * @number_of_packets: Lists the number of ISO transfer buffers.
@@ -811,6 +821,23 @@ typedef void (*usb_complete_t)(struct urb *);
  * are submitted using usb_submit_urb(), and pending requests may be canceled
  * using usb_unlink_urb().
  *
+ * Data Transfer Buffers:
+ *
+ * Normally drivers provide I/O buffers allocated with kmalloc() or otherwise
+ * taken from the general page pool.  That is provided by transfer_buffer
+ * (control requests also use setup_packet), and host controller drivers
+ * perform a dma mapping (and unmapping) for each buffer transferred.  Those
+ * mapping operations can be expensive on some platforms (such using a dma
+ * bounce buffer), although they're cheap on commodity x86 and ppc hardware.
+ *
+ * Alternatively, drivers may pass the URB_NO_DMA_MAP transfer flag, which
+ * tells the host controller driver that no such mapping is needed since
+ * the device driver is DMA-aware.  For example, they might allocate a DMA
+ * buffer with usb_buffer_alloc(), or call usb_buffer_map().
+ * When this transfer flag is provided, host controller drivers will use the
+ * dma addresses found in the transfer_dma and/or setup_dma fields rather than
+ * determing a dma address themselves.
+ *
  * Initialization:
  *
  * All URBs submitted must initialize dev, pipe,
@@ -818,10 +845,10 @@ typedef void (*usb_complete_t)(struct urb *);
  * The USB_ASYNC_UNLINK transfer flag affects later invocations of
  * the usb_unlink_urb() routine.
  *
- * All non-isochronous URBs must also initialize 
+ * All URBs must also initialize 
  * transfer_buffer and transfer_buffer_length.  They may provide the
  * URB_SHORT_NOT_OK transfer flag, indicating that short reads are
- * to be treated as errors.
+ * to be treated as errors; that flag is invalid for write requests.
  *
  * Bulk URBs may
  * use the USB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
@@ -896,10 +923,12 @@ struct urb
 	int status;			/* (return) non-ISO status */
 	unsigned int transfer_flags;	/* (in) URB_SHORT_NOT_OK | ...*/
 	void *transfer_buffer;		/* (in) associated data buffer */
+	dma_addr_t transfer_dma;	/* (in) dma addr for transfer_buffer */
 	int transfer_buffer_length;	/* (in) data buffer length */
 	int actual_length;		/* (return) actual transfer length */
 	int bandwidth;			/* bandwidth for INT/ISO request */
 	unsigned char *setup_packet;	/* (in) setup packet (control only) */
+	dma_addr_t setup_dma;		/* (in) dma addr for setup_packet */
 	int start_frame;		/* (modify) start frame (INT/ISO) */
 	int number_of_packets;		/* (in) number of ISO packets */
 	int interval;			/* (in) transfer interval (INT/ISO) */
@@ -910,6 +939,8 @@ struct urb
 	struct usb_iso_packet_descriptor iso_frame_desc[0];	/* (in) ISO ONLY */
 };
 
+/* -------------------------------------------------------------------------- */
+
 /**
  * usb_fill_control_urb - initializes a control urb
  * @urb: pointer to the urb to initialize.
@@ -1032,6 +1063,16 @@ extern struct urb *usb_get_urb(struct urb *urb);
 extern int usb_submit_urb(struct urb *urb, int mem_flags);
 extern int usb_unlink_urb(struct urb *urb);
 
+#define HAVE_USB_BUFFERS
+void *usb_buffer_alloc (struct usb_device *dev, size_t size,
+	int mem_flags, dma_addr_t *dma);
+void usb_buffer_free (struct usb_device *dev, size_t size,
+	void *addr, dma_addr_t dma);
+
+struct urb *usb_buffer_map (struct urb *urb);
+void usb_buffer_dmasync (struct urb *urb);
+void usb_buffer_unmap (struct urb *urb);
+
 /*-------------------------------------------------------------------*
  *                         SYNCHRONOUS CALL SUPPORT                  *
  *-------------------------------------------------------------------*/