USB: xhci: rename driver to xhci_hcd

Naming consistency with other USB HCDs.

Signed-off-by: Alex Chiang <achiang@hp.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1916 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
new file mode 100644
index 0000000..4cb69e0
--- /dev/null
+++ b/drivers/usb/host/xhci.c
@@ -0,0 +1,1916 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+#include "xhci.h"
+
+#define DRIVER_AUTHOR "Sarah Sharp"
+#define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"
+
+/* Some 0.95 hardware can't handle the chain bit on a Link TRB being cleared */
+static int link_quirk;
+module_param(link_quirk, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(link_quirk, "Don't clear the chain bit on a link TRB");
+
+/* TODO: copied from ehci-hcd.c - can this be refactored? */
+/*
+ * handshake - spin reading hc until handshake completes or fails
+ * @ptr: address of hc register to be read
+ * @mask: bits to look at in result of read
+ * @done: value of those bits when handshake succeeds
+ * @usec: timeout in microseconds
+ *
+ * Returns negative errno, or zero on success
+ *
+ * Success happens when the "mask" bits have the specified value (hardware
+ * handshake done).  There are two failure modes:  "usec" have passed (major
+ * hardware flakeout), or the register reads as all-ones (hardware removed).
+ */
+static int handshake(struct xhci_hcd *xhci, void __iomem *ptr,
+		      u32 mask, u32 done, int usec)
+{
+	u32	result;
+
+	do {
+		result = xhci_readl(xhci, ptr);
+		if (result == ~(u32)0)		/* card removed */
+			return -ENODEV;
+		result &= mask;
+		if (result == done)
+			return 0;
+		udelay(1);
+		usec--;
+	} while (usec > 0);
+	return -ETIMEDOUT;
+}
+
+/*
+ * Disable interrupts and begin the xHCI halting process.
+ */
+void xhci_quiesce(struct xhci_hcd *xhci)
+{
+	u32 halted;
+	u32 cmd;
+	u32 mask;
+
+	mask = ~(XHCI_IRQS);
+	halted = xhci_readl(xhci, &xhci->op_regs->status) & STS_HALT;
+	if (!halted)
+		mask &= ~CMD_RUN;
+
+	cmd = xhci_readl(xhci, &xhci->op_regs->command);
+	cmd &= mask;
+	xhci_writel(xhci, cmd, &xhci->op_regs->command);
+}
+
+/*
+ * Force HC into halt state.
+ *
+ * Disable any IRQs and clear the run/stop bit.
+ * HC will complete any current and actively pipelined transactions, and
+ * should halt within 16 microframes of the run/stop bit being cleared.
+ * Read HC Halted bit in the status register to see when the HC is finished.
+ * XXX: shouldn't we set HC_STATE_HALT here somewhere?
+ */
+int xhci_halt(struct xhci_hcd *xhci)
+{
+	xhci_dbg(xhci, "// Halt the HC\n");
+	xhci_quiesce(xhci);
+
+	return handshake(xhci, &xhci->op_regs->status,
+			STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
+}
+
+/*
+ * Reset a halted HC, and set the internal HC state to HC_STATE_HALT.
+ *
+ * This resets pipelines, timers, counters, state machines, etc.
+ * Transactions will be terminated immediately, and operational registers
+ * will be set to their defaults.
+ */
+int xhci_reset(struct xhci_hcd *xhci)
+{
+	u32 command;
+	u32 state;
+
+	state = xhci_readl(xhci, &xhci->op_regs->status);
+	if ((state & STS_HALT) == 0) {
+		xhci_warn(xhci, "Host controller not halted, aborting reset.\n");
+		return 0;
+	}
+
+	xhci_dbg(xhci, "// Reset the HC\n");
+	command = xhci_readl(xhci, &xhci->op_regs->command);
+	command |= CMD_RESET;
+	xhci_writel(xhci, command, &xhci->op_regs->command);
+	/* XXX: Why does EHCI set this here?  Shouldn't other code do this? */
+	xhci_to_hcd(xhci)->state = HC_STATE_HALT;
+
+	return handshake(xhci, &xhci->op_regs->command, CMD_RESET, 0, 250 * 1000);
+}
+
+
+#if 0
+/* Set up MSI-X table for entry 0 (may claim other entries later) */
+static int xhci_setup_msix(struct xhci_hcd *xhci)
+{
+	int ret;
+	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+
+	xhci->msix_count = 0;
+	/* XXX: did I do this right?  ixgbe does kcalloc for more than one */
+	xhci->msix_entries = kmalloc(sizeof(struct msix_entry), GFP_KERNEL);
+	if (!xhci->msix_entries) {
+		xhci_err(xhci, "Failed to allocate MSI-X entries\n");
+		return -ENOMEM;
+	}
+	xhci->msix_entries[0].entry = 0;
+
+	ret = pci_enable_msix(pdev, xhci->msix_entries, xhci->msix_count);
+	if (ret) {
+		xhci_err(xhci, "Failed to enable MSI-X\n");
+		goto free_entries;
+	}
+
+	/*
+	 * Pass the xhci pointer value as the request_irq "cookie".
+	 * If more irqs are added, this will need to be unique for each one.
+	 */
+	ret = request_irq(xhci->msix_entries[0].vector, &xhci_irq, 0,
+			"xHCI", xhci_to_hcd(xhci));
+	if (ret) {
+		xhci_err(xhci, "Failed to allocate MSI-X interrupt\n");
+		goto disable_msix;
+	}
+	xhci_dbg(xhci, "Finished setting up MSI-X\n");
+	return 0;
+
+disable_msix:
+	pci_disable_msix(pdev);
+free_entries:
+	kfree(xhci->msix_entries);
+	xhci->msix_entries = NULL;
+	return ret;
+}
+
+/* XXX: code duplication; can xhci_setup_msix call this? */
+/* Free any IRQs and disable MSI-X */
+static void xhci_cleanup_msix(struct xhci_hcd *xhci)
+{
+	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+	if (!xhci->msix_entries)
+		return;
+
+	free_irq(xhci->msix_entries[0].vector, xhci);
+	pci_disable_msix(pdev);
+	kfree(xhci->msix_entries);
+	xhci->msix_entries = NULL;
+	xhci_dbg(xhci, "Finished cleaning up MSI-X\n");
+}
+#endif
+
+/*
+ * Initialize memory for HCD and xHC (one-time init).
+ *
+ * Program the PAGESIZE register, initialize the device context array, create
+ * device contexts (?), set up a command ring segment (or two?), create event
+ * ring (one for now).
+ */
+int xhci_init(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	int retval = 0;
+
+	xhci_dbg(xhci, "xhci_init\n");
+	spin_lock_init(&xhci->lock);
+	if (link_quirk) {
+		xhci_dbg(xhci, "QUIRK: Not clearing Link TRB chain bits.\n");
+		xhci->quirks |= XHCI_LINK_TRB_QUIRK;
+	} else {
+		xhci_dbg(xhci, "xHCI doesn't need link TRB QUIRK\n");
+	}
+	retval = xhci_mem_init(xhci, GFP_KERNEL);
+	xhci_dbg(xhci, "Finished xhci_init\n");
+
+	return retval;
+}
+
+/*
+ * Called in interrupt context when there might be work
+ * queued on the event ring
+ *
+ * xhci->lock must be held by caller.
+ */
+static void xhci_work(struct xhci_hcd *xhci)
+{
+	u32 temp;
+	u64 temp_64;
+
+	/*
+	 * Clear the op reg interrupt status first,
+	 * so we can receive interrupts from other MSI-X interrupters.
+	 * Write 1 to clear the interrupt status.
+	 */
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	temp |= STS_EINT;
+	xhci_writel(xhci, temp, &xhci->op_regs->status);
+	/* FIXME when MSI-X is supported and there are multiple vectors */
+	/* Clear the MSI-X event interrupt status */
+
+	/* Acknowledge the interrupt */
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	temp |= 0x3;
+	xhci_writel(xhci, temp, &xhci->ir_set->irq_pending);
+	/* Flush posted writes */
+	xhci_readl(xhci, &xhci->ir_set->irq_pending);
+
+	if (xhci->xhc_state & XHCI_STATE_DYING)
+		xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "
+				"Shouldn't IRQs be disabled?\n");
+	else
+		/* FIXME this should be a delayed service routine
+		 * that clears the EHB.
+		 */
+		xhci_handle_event(xhci);
+
+	/* Clear the event handler busy flag (RW1C); the event ring should be empty. */
+	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+	xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);
+	/* Flush posted writes -- FIXME is this necessary? */
+	xhci_readl(xhci, &xhci->ir_set->irq_pending);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * xHCI spec says we can get an interrupt, and if the HC has an error condition,
+ * we might get bad data out of the event ring.  Section 4.10.2.7 has a list of
+ * indicators of an event TRB error, but we check the status *first* to be safe.
+ */
+irqreturn_t xhci_irq(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	u32 temp, temp2;
+	union xhci_trb *trb;
+
+	spin_lock(&xhci->lock);
+	trb = xhci->event_ring->dequeue;
+	/* Check if the xHC generated the interrupt, or the irq is shared */
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	temp2 = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	if (temp == 0xffffffff && temp2 == 0xffffffff)
+		goto hw_died;
+
+	if (!(temp & STS_EINT) && !ER_IRQ_PENDING(temp2)) {
+		spin_unlock(&xhci->lock);
+		return IRQ_NONE;
+	}
+	xhci_dbg(xhci, "op reg status = %08x\n", temp);
+	xhci_dbg(xhci, "ir set irq_pending = %08x\n", temp2);
+	xhci_dbg(xhci, "Event ring dequeue ptr:\n");
+	xhci_dbg(xhci, "@%llx %08x %08x %08x %08x\n",
+			(unsigned long long)xhci_trb_virt_to_dma(xhci->event_ring->deq_seg, trb),
+			lower_32_bits(trb->link.segment_ptr),
+			upper_32_bits(trb->link.segment_ptr),
+			(unsigned int) trb->link.intr_target,
+			(unsigned int) trb->link.control);
+
+	if (temp & STS_FATAL) {
+		xhci_warn(xhci, "WARNING: Host System Error\n");
+		xhci_halt(xhci);
+hw_died:
+		xhci_to_hcd(xhci)->state = HC_STATE_HALT;
+		spin_unlock(&xhci->lock);
+		return -ESHUTDOWN;
+	}
+
+	xhci_work(xhci);
+	spin_unlock(&xhci->lock);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
+void xhci_event_ring_work(unsigned long arg)
+{
+	unsigned long flags;
+	int temp;
+	u64 temp_64;
+	struct xhci_hcd *xhci = (struct xhci_hcd *) arg;
+	int i, j;
+
+	xhci_dbg(xhci, "Poll event ring: %lu\n", jiffies);
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	xhci_dbg(xhci, "op reg status = 0x%x\n", temp);
+	if (temp == 0xffffffff || (xhci->xhc_state & XHCI_STATE_DYING)) {
+		xhci_dbg(xhci, "HW died, polling stopped.\n");
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return;
+	}
+
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	xhci_dbg(xhci, "ir_set 0 pending = 0x%x\n", temp);
+	xhci_dbg(xhci, "No-op commands handled = %d\n", xhci->noops_handled);
+	xhci_dbg(xhci, "HC error bitmask = 0x%x\n", xhci->error_bitmask);
+	xhci->error_bitmask = 0;
+	xhci_dbg(xhci, "Event ring:\n");
+	xhci_debug_segment(xhci, xhci->event_ring->deq_seg);
+	xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
+	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+	temp_64 &= ~ERST_PTR_MASK;
+	xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
+	xhci_dbg(xhci, "Command ring:\n");
+	xhci_debug_segment(xhci, xhci->cmd_ring->deq_seg);
+	xhci_dbg_ring_ptrs(xhci, xhci->cmd_ring);
+	xhci_dbg_cmd_ptrs(xhci);
+	for (i = 0; i < MAX_HC_SLOTS; ++i) {
+		if (!xhci->devs[i])
+			continue;
+		for (j = 0; j < 31; ++j) {
+			struct xhci_ring *ring = xhci->devs[i]->eps[j].ring;
+			if (!ring)
+				continue;
+			xhci_dbg(xhci, "Dev %d endpoint ring %d:\n", i, j);
+			xhci_debug_segment(xhci, ring->deq_seg);
+		}
+	}
+
+	if (xhci->noops_submitted != NUM_TEST_NOOPS)
+		if (xhci_setup_one_noop(xhci))
+			xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	if (!xhci->zombie)
+		mod_timer(&xhci->event_ring_timer, jiffies + POLL_TIMEOUT * HZ);
+	else
+		xhci_dbg(xhci, "Quit polling the event ring.\n");
+}
+#endif
+
+/*
+ * Start the HC after it was halted.
+ *
+ * This function is called by the USB core when the HC driver is added.
+ * Its opposite is xhci_stop().
+ *
+ * xhci_init() must be called once before this function can be called.
+ * Reset the HC, enable device slot contexts, program DCBAAP, and
+ * set command ring pointer and event ring pointer.
+ *
+ * Setup MSI-X vectors and enable interrupts.
+ */
+int xhci_run(struct usb_hcd *hcd)
+{
+	u32 temp;
+	u64 temp_64;
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	void (*doorbell)(struct xhci_hcd *) = NULL;
+
+	hcd->uses_new_polling = 1;
+	hcd->poll_rh = 0;
+
+	xhci_dbg(xhci, "xhci_run\n");
+#if 0	/* FIXME: MSI not setup yet */
+	/* Do this at the very last minute */
+	ret = xhci_setup_msix(xhci);
+	if (!ret)
+		return ret;
+
+	return -ENOSYS;
+#endif
+#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
+	init_timer(&xhci->event_ring_timer);
+	xhci->event_ring_timer.data = (unsigned long) xhci;
+	xhci->event_ring_timer.function = xhci_event_ring_work;
+	/* Poll the event ring */
+	xhci->event_ring_timer.expires = jiffies + POLL_TIMEOUT * HZ;
+	xhci->zombie = 0;
+	xhci_dbg(xhci, "Setting event ring polling timer\n");
+	add_timer(&xhci->event_ring_timer);
+#endif
+
+	xhci_dbg(xhci, "Command ring memory map follows:\n");
+	xhci_debug_ring(xhci, xhci->cmd_ring);
+	xhci_dbg_ring_ptrs(xhci, xhci->cmd_ring);
+	xhci_dbg_cmd_ptrs(xhci);
+
+	xhci_dbg(xhci, "ERST memory map follows:\n");
+	xhci_dbg_erst(xhci, &xhci->erst);
+	xhci_dbg(xhci, "Event ring:\n");
+	xhci_debug_ring(xhci, xhci->event_ring);
+	xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
+	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
+	temp_64 &= ~ERST_PTR_MASK;
+	xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
+
+	xhci_dbg(xhci, "// Set the interrupt modulation register\n");
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_control);
+	temp &= ~ER_IRQ_INTERVAL_MASK;
+	temp |= (u32) 160;
+	xhci_writel(xhci, temp, &xhci->ir_set->irq_control);
+
+	/* Set the HCD state before we enable the irqs */
+	hcd->state = HC_STATE_RUNNING;
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	temp |= (CMD_EIE);
+	xhci_dbg(xhci, "// Enable interrupts, cmd = 0x%x.\n",
+			temp);
+	xhci_writel(xhci, temp, &xhci->op_regs->command);
+
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	xhci_dbg(xhci, "// Enabling event ring interrupter %p by writing 0x%x to irq_pending\n",
+			xhci->ir_set, (unsigned int) ER_IRQ_ENABLE(temp));
+	xhci_writel(xhci, ER_IRQ_ENABLE(temp),
+			&xhci->ir_set->irq_pending);
+	xhci_print_ir_set(xhci, xhci->ir_set, 0);
+
+	if (NUM_TEST_NOOPS > 0)
+		doorbell = xhci_setup_one_noop(xhci);
+
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	temp |= (CMD_RUN);
+	xhci_dbg(xhci, "// Turn on HC, cmd = 0x%x.\n",
+			temp);
+	xhci_writel(xhci, temp, &xhci->op_regs->command);
+	/* Flush PCI posted writes */
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	xhci_dbg(xhci, "// @%p = 0x%x\n", &xhci->op_regs->command, temp);
+	if (doorbell)
+		(*doorbell)(xhci);
+
+	xhci_dbg(xhci, "Finished xhci_run\n");
+	return 0;
+}
+
+/*
+ * Stop xHCI driver.
+ *
+ * This function is called by the USB core when the HC driver is removed.
+ * Its opposite is xhci_run().
+ *
+ * Disable device contexts, disable IRQs, and quiesce the HC.
+ * Reset the HC, finish any completed transactions, and cleanup memory.
+ */
+void xhci_stop(struct usb_hcd *hcd)
+{
+	u32 temp;
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+	spin_lock_irq(&xhci->lock);
+	xhci_halt(xhci);
+	xhci_reset(xhci);
+	spin_unlock_irq(&xhci->lock);
+
+#if 0	/* No MSI yet */
+	xhci_cleanup_msix(xhci);
+#endif
+#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
+	/* Tell the event ring poll function not to reschedule */
+	xhci->zombie = 1;
+	del_timer_sync(&xhci->event_ring_timer);
+#endif
+
+	xhci_dbg(xhci, "// Disabling event ring interrupts\n");
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	xhci_writel(xhci, temp & ~STS_EINT, &xhci->op_regs->status);
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	xhci_writel(xhci, ER_IRQ_DISABLE(temp),
+			&xhci->ir_set->irq_pending);
+	xhci_print_ir_set(xhci, xhci->ir_set, 0);
+
+	xhci_dbg(xhci, "cleaning up memory\n");
+	xhci_mem_cleanup(xhci);
+	xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
+		    xhci_readl(xhci, &xhci->op_regs->status));
+}
+
+/*
+ * Shutdown HC (not bus-specific)
+ *
+ * This is called when the machine is rebooting or halting.  We assume that the
+ * machine will be powered off, and the HC's internal state will be reset.
+ * Don't bother to free memory.
+ */
+void xhci_shutdown(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+	spin_lock_irq(&xhci->lock);
+	xhci_halt(xhci);
+	spin_unlock_irq(&xhci->lock);
+
+#if 0
+	xhci_cleanup_msix(xhci);
+#endif
+
+	xhci_dbg(xhci, "xhci_shutdown completed - status = %x\n",
+		    xhci_readl(xhci, &xhci->op_regs->status));
+}
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * xhci_get_endpoint_index - Used for passing endpoint bitmasks between the core and
+ * HCDs.  Find the index for an endpoint given its descriptor.  Use the return
+ * value to right shift 1 for the bitmask.
+ *
+ * Index  = (epnum * 2) + direction - 1,
+ * where direction = 0 for OUT, 1 for IN.
+ * For control endpoints, the IN index is used (OUT index is unused), so
+ * index = (epnum * 2) + direction - 1 = (epnum * 2) + 1 - 1 = (epnum * 2)
+ */
+unsigned int xhci_get_endpoint_index(struct usb_endpoint_descriptor *desc)
+{
+	unsigned int index;
+	if (usb_endpoint_xfer_control(desc))
+		index = (unsigned int) (usb_endpoint_num(desc)*2);
+	else
+		index = (unsigned int) (usb_endpoint_num(desc)*2) +
+			(usb_endpoint_dir_in(desc) ? 1 : 0) - 1;
+	return index;
+}
+
+/* Find the flag for this endpoint (for use in the control context).  Use the
+ * endpoint index to create a bitmask.  The slot context is bit 0, endpoint 0 is
+ * bit 1, etc.
+ */
+unsigned int xhci_get_endpoint_flag(struct usb_endpoint_descriptor *desc)
+{
+	return 1 << (xhci_get_endpoint_index(desc) + 1);
+}
+
+/* Find the flag for this endpoint (for use in the control context).  Use the
+ * endpoint index to create a bitmask.  The slot context is bit 0, endpoint 0 is
+ * bit 1, etc.
+ */
+unsigned int xhci_get_endpoint_flag_from_index(unsigned int ep_index)
+{
+	return 1 << (ep_index + 1);
+}
+
+/* Compute the last valid endpoint context index.  Basically, this is the
+ * endpoint index plus one.  For slot contexts with more than valid endpoint,
+ * we find the most significant bit set in the added contexts flags.
+ * e.g. ep 1 IN (with epnum 0x81) => added_ctxs = 0b1000
+ * fls(0b1000) = 4, but the endpoint context index is 3, so subtract one.
+ */
+unsigned int xhci_last_valid_endpoint(u32 added_ctxs)
+{
+	return fls(added_ctxs) - 1;
+}
+
+/* Returns 1 if the arguments are OK;
+ * returns 0 this is a root hub; returns -EINVAL for NULL pointers.
+ */
+int xhci_check_args(struct usb_hcd *hcd, struct usb_device *udev,
+		struct usb_host_endpoint *ep, int check_ep, const char *func) {
+	if (!hcd || (check_ep && !ep) || !udev) {
+		printk(KERN_DEBUG "xHCI %s called with invalid args\n",
+				func);
+		return -EINVAL;
+	}
+	if (!udev->parent) {
+		printk(KERN_DEBUG "xHCI %s called for root hub\n",
+				func);
+		return 0;
+	}
+	if (!udev->slot_id) {
+		printk(KERN_DEBUG "xHCI %s called with unaddressed device\n",
+				func);
+		return -EINVAL;
+	}
+	return 1;
+}
+
+static int xhci_configure_endpoint(struct xhci_hcd *xhci,
+		struct usb_device *udev, struct xhci_command *command,
+		bool ctx_change, bool must_succeed);
+
+/*
+ * Full speed devices may have a max packet size greater than 8 bytes, but the
+ * USB core doesn't know that until it reads the first 8 bytes of the
+ * descriptor.  If the usb_device's max packet size changes after that point,
+ * we need to issue an evaluate context command and wait on it.
+ */
+static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id,
+		unsigned int ep_index, struct urb *urb)
+{
+	struct xhci_container_ctx *in_ctx;
+	struct xhci_container_ctx *out_ctx;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_ep_ctx *ep_ctx;
+	int max_packet_size;
+	int hw_max_packet_size;
+	int ret = 0;
+
+	out_ctx = xhci->devs[slot_id]->out_ctx;
+	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
+	hw_max_packet_size = MAX_PACKET_DECODED(ep_ctx->ep_info2);
+	max_packet_size = urb->dev->ep0.desc.wMaxPacketSize;
+	if (hw_max_packet_size != max_packet_size) {
+		xhci_dbg(xhci, "Max Packet Size for ep 0 changed.\n");
+		xhci_dbg(xhci, "Max packet size in usb_device = %d\n",
+				max_packet_size);
+		xhci_dbg(xhci, "Max packet size in xHCI HW = %d\n",
+				hw_max_packet_size);
+		xhci_dbg(xhci, "Issuing evaluate context command.\n");
+
+		/* Set up the modified control endpoint 0 */
+		xhci_endpoint_copy(xhci, xhci->devs[slot_id]->in_ctx,
+				xhci->devs[slot_id]->out_ctx, ep_index);
+		in_ctx = xhci->devs[slot_id]->in_ctx;
+		ep_ctx = xhci_get_ep_ctx(xhci, in_ctx, ep_index);
+		ep_ctx->ep_info2 &= ~MAX_PACKET_MASK;
+		ep_ctx->ep_info2 |= MAX_PACKET(max_packet_size);
+
+		/* Set up the input context flags for the command */
+		/* FIXME: This won't work if a non-default control endpoint
+		 * changes max packet sizes.
+		 */
+		ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+		ctrl_ctx->add_flags = EP0_FLAG;
+		ctrl_ctx->drop_flags = 0;
+
+		xhci_dbg(xhci, "Slot %d input context\n", slot_id);
+		xhci_dbg_ctx(xhci, in_ctx, ep_index);
+		xhci_dbg(xhci, "Slot %d output context\n", slot_id);
+		xhci_dbg_ctx(xhci, out_ctx, ep_index);
+
+		ret = xhci_configure_endpoint(xhci, urb->dev, NULL,
+				true, false);
+
+		/* Clean up the input context for later use by bandwidth
+		 * functions.
+		 */
+		ctrl_ctx->add_flags = SLOT_FLAG;
+	}
+	return ret;
+}
+
+/*
+ * non-error returns are a promise to giveback() the urb later
+ * we drop ownership so next owner (or urb unlink) can get it
+ */
+int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	unsigned long flags;
+	int ret = 0;
+	unsigned int slot_id, ep_index;
+
+
+	if (!urb || xhci_check_args(hcd, urb->dev, urb->ep, true, __func__) <= 0)
+		return -EINVAL;
+
+	slot_id = urb->dev->slot_id;
+	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
+
+	if (!xhci->devs || !xhci->devs[slot_id]) {
+		if (!in_interrupt())
+			dev_warn(&urb->dev->dev, "WARN: urb submitted for dev with no Slot ID\n");
+		ret = -EINVAL;
+		goto exit;
+	}
+	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
+		if (!in_interrupt())
+			xhci_dbg(xhci, "urb submitted during PCI suspend\n");
+		ret = -ESHUTDOWN;
+		goto exit;
+	}
+	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
+		/* Check to see if the max packet size for the default control
+		 * endpoint changed during FS device enumeration
+		 */
+		if (urb->dev->speed == USB_SPEED_FULL) {
+			ret = xhci_check_maxpacket(xhci, slot_id,
+					ep_index, urb);
+			if (ret < 0)
+				return ret;
+		}
+
+		/* We have a spinlock and interrupts disabled, so we must pass
+		 * atomic context to this function, which may allocate memory.
+		 */
+		spin_lock_irqsave(&xhci->lock, flags);
+		if (xhci->xhc_state & XHCI_STATE_DYING)
+			goto dying;
+		ret = xhci_queue_ctrl_tx(xhci, GFP_ATOMIC, urb,
+				slot_id, ep_index);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+	} else if (usb_endpoint_xfer_bulk(&urb->ep->desc)) {
+		spin_lock_irqsave(&xhci->lock, flags);
+		if (xhci->xhc_state & XHCI_STATE_DYING)
+			goto dying;
+		ret = xhci_queue_bulk_tx(xhci, GFP_ATOMIC, urb,
+				slot_id, ep_index);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+	} else if (usb_endpoint_xfer_int(&urb->ep->desc)) {
+		spin_lock_irqsave(&xhci->lock, flags);
+		if (xhci->xhc_state & XHCI_STATE_DYING)
+			goto dying;
+		ret = xhci_queue_intr_tx(xhci, GFP_ATOMIC, urb,
+				slot_id, ep_index);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+	} else {
+		ret = -EINVAL;
+	}
+exit:
+	return ret;
+dying:
+	xhci_dbg(xhci, "Ep 0x%x: URB %p submitted for "
+			"non-responsive xHCI host.\n",
+			urb->ep->desc.bEndpointAddress, urb);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+	return -ESHUTDOWN;
+}
+
+/*
+ * Remove the URB's TD from the endpoint ring.  This may cause the HC to stop
+ * USB transfers, potentially stopping in the middle of a TRB buffer.  The HC
+ * should pick up where it left off in the TD, unless a Set Transfer Ring
+ * Dequeue Pointer is issued.
+ *
+ * The TRBs that make up the buffers for the canceled URB will be "removed" from
+ * the ring.  Since the ring is a contiguous structure, they can't be physically
+ * removed.  Instead, there are two options:
+ *
+ *  1) If the HC is in the middle of processing the URB to be canceled, we
+ *     simply move the ring's dequeue pointer past those TRBs using the Set
+ *     Transfer Ring Dequeue Pointer command.  This will be the common case,
+ *     when drivers timeout on the last submitted URB and attempt to cancel.
+ *
+ *  2) If the HC is in the middle of a different TD, we turn the TRBs into a
+ *     series of 1-TRB transfer no-op TDs.  (No-ops shouldn't be chained.)  The
+ *     HC will need to invalidate the any TRBs it has cached after the stop
+ *     endpoint command, as noted in the xHCI 0.95 errata.
+ *
+ *  3) The TD may have completed by the time the Stop Endpoint Command
+ *     completes, so software needs to handle that case too.
+ *
+ * This function should protect against the TD enqueueing code ringing the
+ * doorbell while this code is waiting for a Stop Endpoint command to complete.
+ * It also needs to account for multiple cancellations on happening at the same
+ * time for the same endpoint.
+ *
+ * Note that this function can be called in any context, or so says
+ * usb_hcd_unlink_urb()
+ */
+int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+	unsigned long flags;
+	int ret;
+	u32 temp;
+	struct xhci_hcd *xhci;
+	struct xhci_td *td;
+	unsigned int ep_index;
+	struct xhci_ring *ep_ring;
+	struct xhci_virt_ep *ep;
+
+	xhci = hcd_to_xhci(hcd);
+	spin_lock_irqsave(&xhci->lock, flags);
+	/* Make sure the URB hasn't completed or been unlinked already */
+	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
+	if (ret || !urb->hcpriv)
+		goto done;
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	if (temp == 0xffffffff) {
+		xhci_dbg(xhci, "HW died, freeing TD.\n");
+		td = (struct xhci_td *) urb->hcpriv;
+
+		usb_hcd_unlink_urb_from_ep(hcd, urb);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, -ESHUTDOWN);
+		kfree(td);
+		return ret;
+	}
+	if (xhci->xhc_state & XHCI_STATE_DYING) {
+		xhci_dbg(xhci, "Ep 0x%x: URB %p to be canceled on "
+				"non-responsive xHCI host.\n",
+				urb->ep->desc.bEndpointAddress, urb);
+		/* Let the stop endpoint command watchdog timer (which set this
+		 * state) finish cleaning up the endpoint TD lists.  We must
+		 * have caught it in the middle of dropping a lock and giving
+		 * back an URB.
+		 */
+		goto done;
+	}
+
+	xhci_dbg(xhci, "Cancel URB %p\n", urb);
+	xhci_dbg(xhci, "Event ring:\n");
+	xhci_debug_ring(xhci, xhci->event_ring);
+	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
+	ep = &xhci->devs[urb->dev->slot_id]->eps[ep_index];
+	ep_ring = ep->ring;
+	xhci_dbg(xhci, "Endpoint ring:\n");
+	xhci_debug_ring(xhci, ep_ring);
+	td = (struct xhci_td *) urb->hcpriv;
+
+	list_add_tail(&td->cancelled_td_list, &ep->cancelled_td_list);
+	/* Queue a stop endpoint command, but only if this is
+	 * the first cancellation to be handled.
+	 */
+	if (!(ep->ep_state & EP_HALT_PENDING)) {
+		ep->ep_state |= EP_HALT_PENDING;
+		ep->stop_cmds_pending++;
+		ep->stop_cmd_timer.expires = jiffies +
+			XHCI_STOP_EP_CMD_TIMEOUT * HZ;
+		add_timer(&ep->stop_cmd_timer);
+		xhci_queue_stop_endpoint(xhci, urb->dev->slot_id, ep_index);
+		xhci_ring_cmd_db(xhci);
+	}
+done:
+	spin_unlock_irqrestore(&xhci->lock, flags);
+	return ret;
+}
+
+/* Drop an endpoint from a new bandwidth configuration for this device.
+ * Only one call to this function is allowed per endpoint before
+ * check_bandwidth() or reset_bandwidth() must be called.
+ * A call to xhci_drop_endpoint() followed by a call to xhci_add_endpoint() will
+ * add the endpoint to the schedule with possibly new parameters denoted by a
+ * different endpoint descriptor in usb_host_endpoint.
+ * A call to xhci_add_endpoint() followed by a call to xhci_drop_endpoint() is
+ * not allowed.
+ *
+ * The USB core will not allow URBs to be queued to an endpoint that is being
+ * disabled, so there's no need for mutual exclusion to protect
+ * the xhci->devs[slot_id] structure.
+ */
+int xhci_drop_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
+		struct usb_host_endpoint *ep)
+{
+	struct xhci_hcd *xhci;
+	struct xhci_container_ctx *in_ctx, *out_ctx;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+	unsigned int last_ctx;
+	unsigned int ep_index;
+	struct xhci_ep_ctx *ep_ctx;
+	u32 drop_flag;
+	u32 new_add_flags, new_drop_flags, new_slot_info;
+	int ret;
+
+	ret = xhci_check_args(hcd, udev, ep, 1, __func__);
+	if (ret <= 0)
+		return ret;
+	xhci = hcd_to_xhci(hcd);
+	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
+
+	drop_flag = xhci_get_endpoint_flag(&ep->desc);
+	if (drop_flag == SLOT_FLAG || drop_flag == EP0_FLAG) {
+		xhci_dbg(xhci, "xHCI %s - can't drop slot or ep 0 %#x\n",
+				__func__, drop_flag);
+		return 0;
+	}
+
+	if (!xhci->devs || !xhci->devs[udev->slot_id]) {
+		xhci_warn(xhci, "xHCI %s called with unaddressed device\n",
+				__func__);
+		return -EINVAL;
+	}
+
+	in_ctx = xhci->devs[udev->slot_id]->in_ctx;
+	out_ctx = xhci->devs[udev->slot_id]->out_ctx;
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+	ep_index = xhci_get_endpoint_index(&ep->desc);
+	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
+	/* If the HC already knows the endpoint is disabled,
+	 * or the HCD has noted it is disabled, ignore this request
+	 */
+	if ((ep_ctx->ep_info & EP_STATE_MASK) == EP_STATE_DISABLED ||
+			ctrl_ctx->drop_flags & xhci_get_endpoint_flag(&ep->desc)) {
+		xhci_warn(xhci, "xHCI %s called with disabled ep %p\n",
+				__func__, ep);
+		return 0;
+	}
+
+	ctrl_ctx->drop_flags |= drop_flag;
+	new_drop_flags = ctrl_ctx->drop_flags;
+
+	ctrl_ctx->add_flags &= ~drop_flag;
+	new_add_flags = ctrl_ctx->add_flags;
+
+	last_ctx = xhci_last_valid_endpoint(ctrl_ctx->add_flags);
+	slot_ctx = xhci_get_slot_ctx(xhci, in_ctx);
+	/* Update the last valid endpoint context, if we deleted the last one */
+	if ((slot_ctx->dev_info & LAST_CTX_MASK) > LAST_CTX(last_ctx)) {
+		slot_ctx->dev_info &= ~LAST_CTX_MASK;
+		slot_ctx->dev_info |= LAST_CTX(last_ctx);
+	}
+	new_slot_info = slot_ctx->dev_info;
+
+	xhci_endpoint_zero(xhci, xhci->devs[udev->slot_id], ep);
+
+	xhci_dbg(xhci, "drop ep 0x%x, slot id %d, new drop flags = %#x, new add flags = %#x, new slot info = %#x\n",
+			(unsigned int) ep->desc.bEndpointAddress,
+			udev->slot_id,
+			(unsigned int) new_drop_flags,
+			(unsigned int) new_add_flags,
+			(unsigned int) new_slot_info);
+	return 0;
+}
+
+/* Add an endpoint to a new possible bandwidth configuration for this device.
+ * Only one call to this function is allowed per endpoint before
+ * check_bandwidth() or reset_bandwidth() must be called.
+ * A call to xhci_drop_endpoint() followed by a call to xhci_add_endpoint() will
+ * add the endpoint to the schedule with possibly new parameters denoted by a
+ * different endpoint descriptor in usb_host_endpoint.
+ * A call to xhci_add_endpoint() followed by a call to xhci_drop_endpoint() is
+ * not allowed.
+ *
+ * The USB core will not allow URBs to be queued to an endpoint until the
+ * configuration or alt setting is installed in the device, so there's no need
+ * for mutual exclusion to protect the xhci->devs[slot_id] structure.
+ */
+int xhci_add_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
+		struct usb_host_endpoint *ep)
+{
+	struct xhci_hcd *xhci;
+	struct xhci_container_ctx *in_ctx, *out_ctx;
+	unsigned int ep_index;
+	struct xhci_ep_ctx *ep_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	u32 added_ctxs;
+	unsigned int last_ctx;
+	u32 new_add_flags, new_drop_flags, new_slot_info;
+	int ret = 0;
+
+	ret = xhci_check_args(hcd, udev, ep, 1, __func__);
+	if (ret <= 0) {
+		/* So we won't queue a reset ep command for a root hub */
+		ep->hcpriv = NULL;
+		return ret;
+	}
+	xhci = hcd_to_xhci(hcd);
+
+	added_ctxs = xhci_get_endpoint_flag(&ep->desc);
+	last_ctx = xhci_last_valid_endpoint(added_ctxs);
+	if (added_ctxs == SLOT_FLAG || added_ctxs == EP0_FLAG) {
+		/* FIXME when we have to issue an evaluate endpoint command to
+		 * deal with ep0 max packet size changing once we get the
+		 * descriptors
+		 */
+		xhci_dbg(xhci, "xHCI %s - can't add slot or ep 0 %#x\n",
+				__func__, added_ctxs);
+		return 0;
+	}
+
+	if (!xhci->devs || !xhci->devs[udev->slot_id]) {
+		xhci_warn(xhci, "xHCI %s called with unaddressed device\n",
+				__func__);
+		return -EINVAL;
+	}
+
+	in_ctx = xhci->devs[udev->slot_id]->in_ctx;
+	out_ctx = xhci->devs[udev->slot_id]->out_ctx;
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+	ep_index = xhci_get_endpoint_index(&ep->desc);
+	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
+	/* If the HCD has already noted the endpoint is enabled,
+	 * ignore this request.
+	 */
+	if (ctrl_ctx->add_flags & xhci_get_endpoint_flag(&ep->desc)) {
+		xhci_warn(xhci, "xHCI %s called with enabled ep %p\n",
+				__func__, ep);
+		return 0;
+	}
+
+	/*
+	 * Configuration and alternate setting changes must be done in
+	 * process context, not interrupt context (or so documenation
+	 * for usb_set_interface() and usb_set_configuration() claim).
+	 */
+	if (xhci_endpoint_init(xhci, xhci->devs[udev->slot_id],
+				udev, ep, GFP_NOIO) < 0) {
+		dev_dbg(&udev->dev, "%s - could not initialize ep %#x\n",
+				__func__, ep->desc.bEndpointAddress);
+		return -ENOMEM;
+	}
+
+	ctrl_ctx->add_flags |= added_ctxs;
+	new_add_flags = ctrl_ctx->add_flags;
+
+	/* If xhci_endpoint_disable() was called for this endpoint, but the
+	 * xHC hasn't been notified yet through the check_bandwidth() call,
+	 * this re-adds a new state for the endpoint from the new endpoint
+	 * descriptors.  We must drop and re-add this endpoint, so we leave the
+	 * drop flags alone.
+	 */
+	new_drop_flags = ctrl_ctx->drop_flags;
+
+	slot_ctx = xhci_get_slot_ctx(xhci, in_ctx);
+	/* Update the last valid endpoint context, if we just added one past */
+	if ((slot_ctx->dev_info & LAST_CTX_MASK) < LAST_CTX(last_ctx)) {
+		slot_ctx->dev_info &= ~LAST_CTX_MASK;
+		slot_ctx->dev_info |= LAST_CTX(last_ctx);
+	}
+	new_slot_info = slot_ctx->dev_info;
+
+	/* Store the usb_device pointer for later use */
+	ep->hcpriv = udev;
+
+	xhci_dbg(xhci, "add ep 0x%x, slot id %d, new drop flags = %#x, new add flags = %#x, new slot info = %#x\n",
+			(unsigned int) ep->desc.bEndpointAddress,
+			udev->slot_id,
+			(unsigned int) new_drop_flags,
+			(unsigned int) new_add_flags,
+			(unsigned int) new_slot_info);
+	return 0;
+}
+
+static void xhci_zero_in_ctx(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev)
+{
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_ep_ctx *ep_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+	int i;
+
+	/* When a device's add flag and drop flag are zero, any subsequent
+	 * configure endpoint command will leave that endpoint's state
+	 * untouched.  Make sure we don't leave any old state in the input
+	 * endpoint contexts.
+	 */
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
+	ctrl_ctx->drop_flags = 0;
+	ctrl_ctx->add_flags = 0;
+	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
+	slot_ctx->dev_info &= ~LAST_CTX_MASK;
+	/* Endpoint 0 is always valid */
+	slot_ctx->dev_info |= LAST_CTX(1);
+	for (i = 1; i < 31; ++i) {
+		ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, i);
+		ep_ctx->ep_info = 0;
+		ep_ctx->ep_info2 = 0;
+		ep_ctx->deq = 0;
+		ep_ctx->tx_info = 0;
+	}
+}
+
+static int xhci_configure_endpoint_result(struct xhci_hcd *xhci,
+		struct usb_device *udev, int *cmd_status)
+{
+	int ret;
+
+	switch (*cmd_status) {
+	case COMP_ENOMEM:
+		dev_warn(&udev->dev, "Not enough host controller resources "
+				"for new device state.\n");
+		ret = -ENOMEM;
+		/* FIXME: can we allocate more resources for the HC? */
+		break;
+	case COMP_BW_ERR:
+		dev_warn(&udev->dev, "Not enough bandwidth "
+				"for new device state.\n");
+		ret = -ENOSPC;
+		/* FIXME: can we go back to the old state? */
+		break;
+	case COMP_TRB_ERR:
+		/* the HCD set up something wrong */
+		dev_warn(&udev->dev, "ERROR: Endpoint drop flag = 0, "
+				"add flag = 1, "
+				"and endpoint is not disabled.\n");
+		ret = -EINVAL;
+		break;
+	case COMP_SUCCESS:
+		dev_dbg(&udev->dev, "Successful Endpoint Configure command\n");
+		ret = 0;
+		break;
+	default:
+		xhci_err(xhci, "ERROR: unexpected command completion "
+				"code 0x%x.\n", *cmd_status);
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int xhci_evaluate_context_result(struct xhci_hcd *xhci,
+		struct usb_device *udev, int *cmd_status)
+{
+	int ret;
+	struct xhci_virt_device *virt_dev = xhci->devs[udev->slot_id];
+
+	switch (*cmd_status) {
+	case COMP_EINVAL:
+		dev_warn(&udev->dev, "WARN: xHCI driver setup invalid evaluate "
+				"context command.\n");
+		ret = -EINVAL;
+		break;
+	case COMP_EBADSLT:
+		dev_warn(&udev->dev, "WARN: slot not enabled for"
+				"evaluate context command.\n");
+	case COMP_CTX_STATE:
+		dev_warn(&udev->dev, "WARN: invalid context state for "
+				"evaluate context command.\n");
+		xhci_dbg_ctx(xhci, virt_dev->out_ctx, 1);
+		ret = -EINVAL;
+		break;
+	case COMP_SUCCESS:
+		dev_dbg(&udev->dev, "Successful evaluate context command\n");
+		ret = 0;
+		break;
+	default:
+		xhci_err(xhci, "ERROR: unexpected command completion "
+				"code 0x%x.\n", *cmd_status);
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+/* Issue a configure endpoint command or evaluate context command
+ * and wait for it to finish.
+ */
+static int xhci_configure_endpoint(struct xhci_hcd *xhci,
+		struct usb_device *udev,
+		struct xhci_command *command,
+		bool ctx_change, bool must_succeed)
+{
+	int ret;
+	int timeleft;
+	unsigned long flags;
+	struct xhci_container_ctx *in_ctx;
+	struct completion *cmd_completion;
+	int *cmd_status;
+	struct xhci_virt_device *virt_dev;
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	virt_dev = xhci->devs[udev->slot_id];
+	if (command) {
+		in_ctx = command->in_ctx;
+		cmd_completion = command->completion;
+		cmd_status = &command->status;
+		command->command_trb = xhci->cmd_ring->enqueue;
+		list_add_tail(&command->cmd_list, &virt_dev->cmd_list);
+	} else {
+		in_ctx = virt_dev->in_ctx;
+		cmd_completion = &virt_dev->cmd_completion;
+		cmd_status = &virt_dev->cmd_status;
+	}
+
+	if (!ctx_change)
+		ret = xhci_queue_configure_endpoint(xhci, in_ctx->dma,
+				udev->slot_id, must_succeed);
+	else
+		ret = xhci_queue_evaluate_context(xhci, in_ctx->dma,
+				udev->slot_id);
+	if (ret < 0) {
+		if (command)
+			list_del(&command->cmd_list);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_dbg(xhci, "FIXME allocate a new ring segment\n");
+		return -ENOMEM;
+	}
+	xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	/* Wait for the configure endpoint command to complete */
+	timeleft = wait_for_completion_interruptible_timeout(
+			cmd_completion,
+			USB_CTRL_SET_TIMEOUT);
+	if (timeleft <= 0) {
+		xhci_warn(xhci, "%s while waiting for %s command\n",
+				timeleft == 0 ? "Timeout" : "Signal",
+				ctx_change == 0 ?
+					"configure endpoint" :
+					"evaluate context");
+		/* FIXME cancel the configure endpoint command */
+		return -ETIME;
+	}
+
+	if (!ctx_change)
+		return xhci_configure_endpoint_result(xhci, udev, cmd_status);
+	return xhci_evaluate_context_result(xhci, udev, cmd_status);
+}
+
+/* Called after one or more calls to xhci_add_endpoint() or
+ * xhci_drop_endpoint().  If this call fails, the USB core is expected
+ * to call xhci_reset_bandwidth().
+ *
+ * Since we are in the middle of changing either configuration or
+ * installing a new alt setting, the USB core won't allow URBs to be
+ * enqueued for any endpoint on the old config or interface.  Nothing
+ * else should be touching the xhci->devs[slot_id] structure, so we
+ * don't need to take the xhci->lock for manipulating that.
+ */
+int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	int i;
+	int ret = 0;
+	struct xhci_hcd *xhci;
+	struct xhci_virt_device	*virt_dev;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+
+	ret = xhci_check_args(hcd, udev, NULL, 0, __func__);
+	if (ret <= 0)
+		return ret;
+	xhci = hcd_to_xhci(hcd);
+
+	if (!udev->slot_id || !xhci->devs || !xhci->devs[udev->slot_id]) {
+		xhci_warn(xhci, "xHCI %s called with unaddressed device\n",
+				__func__);
+		return -EINVAL;
+	}
+	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
+	virt_dev = xhci->devs[udev->slot_id];
+
+	/* See section 4.6.6 - A0 = 1; A1 = D0 = D1 = 0 */
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
+	ctrl_ctx->add_flags |= SLOT_FLAG;
+	ctrl_ctx->add_flags &= ~EP0_FLAG;
+	ctrl_ctx->drop_flags &= ~SLOT_FLAG;
+	ctrl_ctx->drop_flags &= ~EP0_FLAG;
+	xhci_dbg(xhci, "New Input Control Context:\n");
+	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
+	xhci_dbg_ctx(xhci, virt_dev->in_ctx,
+			LAST_CTX_TO_EP_NUM(slot_ctx->dev_info));
+
+	ret = xhci_configure_endpoint(xhci, udev, NULL,
+			false, false);
+	if (ret) {
+		/* Callee should call reset_bandwidth() */
+		return ret;
+	}
+
+	xhci_dbg(xhci, "Output context after successful config ep cmd:\n");
+	xhci_dbg_ctx(xhci, virt_dev->out_ctx,
+			LAST_CTX_TO_EP_NUM(slot_ctx->dev_info));
+
+	xhci_zero_in_ctx(xhci, virt_dev);
+	/* Install new rings and free or cache any old rings */
+	for (i = 1; i < 31; ++i) {
+		if (!virt_dev->eps[i].new_ring)
+			continue;
+		/* Only cache or free the old ring if it exists.
+		 * It may not if this is the first add of an endpoint.
+		 */
+		if (virt_dev->eps[i].ring) {
+			xhci_free_or_cache_endpoint_ring(xhci, virt_dev, i);
+		}
+		virt_dev->eps[i].ring = virt_dev->eps[i].new_ring;
+		virt_dev->eps[i].new_ring = NULL;
+	}
+
+	return ret;
+}
+
+void xhci_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	struct xhci_hcd *xhci;
+	struct xhci_virt_device	*virt_dev;
+	int i, ret;
+
+	ret = xhci_check_args(hcd, udev, NULL, 0, __func__);
+	if (ret <= 0)
+		return;
+	xhci = hcd_to_xhci(hcd);
+
+	if (!xhci->devs || !xhci->devs[udev->slot_id]) {
+		xhci_warn(xhci, "xHCI %s called with unaddressed device\n",
+				__func__);
+		return;
+	}
+	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
+	virt_dev = xhci->devs[udev->slot_id];
+	/* Free any rings allocated for added endpoints */
+	for (i = 0; i < 31; ++i) {
+		if (virt_dev->eps[i].new_ring) {
+			xhci_ring_free(xhci, virt_dev->eps[i].new_ring);
+			virt_dev->eps[i].new_ring = NULL;
+		}
+	}
+	xhci_zero_in_ctx(xhci, virt_dev);
+}
+
+static void xhci_setup_input_ctx_for_config_ep(struct xhci_hcd *xhci,
+		struct xhci_container_ctx *in_ctx,
+		struct xhci_container_ctx *out_ctx,
+		u32 add_flags, u32 drop_flags)
+{
+	struct xhci_input_control_ctx *ctrl_ctx;
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
+	ctrl_ctx->add_flags = add_flags;
+	ctrl_ctx->drop_flags = drop_flags;
+	xhci_slot_copy(xhci, in_ctx, out_ctx);
+	ctrl_ctx->add_flags |= SLOT_FLAG;
+
+	xhci_dbg(xhci, "Input Context:\n");
+	xhci_dbg_ctx(xhci, in_ctx, xhci_last_valid_endpoint(add_flags));
+}
+
+void xhci_setup_input_ctx_for_quirk(struct xhci_hcd *xhci,
+		unsigned int slot_id, unsigned int ep_index,
+		struct xhci_dequeue_state *deq_state)
+{
+	struct xhci_container_ctx *in_ctx;
+	struct xhci_ep_ctx *ep_ctx;
+	u32 added_ctxs;
+	dma_addr_t addr;
+
+	xhci_endpoint_copy(xhci, xhci->devs[slot_id]->in_ctx,
+			xhci->devs[slot_id]->out_ctx, ep_index);
+	in_ctx = xhci->devs[slot_id]->in_ctx;
+	ep_ctx = xhci_get_ep_ctx(xhci, in_ctx, ep_index);
+	addr = xhci_trb_virt_to_dma(deq_state->new_deq_seg,
+			deq_state->new_deq_ptr);
+	if (addr == 0) {
+		xhci_warn(xhci, "WARN Cannot submit config ep after "
+				"reset ep command\n");
+		xhci_warn(xhci, "WARN deq seg = %p, deq ptr = %p\n",
+				deq_state->new_deq_seg,
+				deq_state->new_deq_ptr);
+		return;
+	}
+	ep_ctx->deq = addr | deq_state->new_cycle_state;
+
+	added_ctxs = xhci_get_endpoint_flag_from_index(ep_index);
+	xhci_setup_input_ctx_for_config_ep(xhci, xhci->devs[slot_id]->in_ctx,
+			xhci->devs[slot_id]->out_ctx, added_ctxs, added_ctxs);
+}
+
+void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
+		struct usb_device *udev, unsigned int ep_index)
+{
+	struct xhci_dequeue_state deq_state;
+	struct xhci_virt_ep *ep;
+
+	xhci_dbg(xhci, "Cleaning up stalled endpoint ring\n");
+	ep = &xhci->devs[udev->slot_id]->eps[ep_index];
+	/* We need to move the HW's dequeue pointer past this TD,
+	 * or it will attempt to resend it on the next doorbell ring.
+	 */
+	xhci_find_new_dequeue_state(xhci, udev->slot_id,
+			ep_index, ep->stopped_td,
+			&deq_state);
+
+	/* HW with the reset endpoint quirk will use the saved dequeue state to
+	 * issue a configure endpoint command later.
+	 */
+	if (!(xhci->quirks & XHCI_RESET_EP_QUIRK)) {
+		xhci_dbg(xhci, "Queueing new dequeue state\n");
+		xhci_queue_new_dequeue_state(xhci, udev->slot_id,
+				ep_index, &deq_state);
+	} else {
+		/* Better hope no one uses the input context between now and the
+		 * reset endpoint completion!
+		 */
+		xhci_dbg(xhci, "Setting up input context for "
+				"configure endpoint command\n");
+		xhci_setup_input_ctx_for_quirk(xhci, udev->slot_id,
+				ep_index, &deq_state);
+	}
+}
+
+/* Deal with stalled endpoints.  The core should have sent the control message
+ * to clear the halt condition.  However, we need to make the xHCI hardware
+ * reset its sequence number, since a device will expect a sequence number of
+ * zero after the halt condition is cleared.
+ * Context: in_interrupt
+ */
+void xhci_endpoint_reset(struct usb_hcd *hcd,
+		struct usb_host_endpoint *ep)
+{
+	struct xhci_hcd *xhci;
+	struct usb_device *udev;
+	unsigned int ep_index;
+	unsigned long flags;
+	int ret;
+	struct xhci_virt_ep *virt_ep;
+
+	xhci = hcd_to_xhci(hcd);
+	udev = (struct usb_device *) ep->hcpriv;
+	/* Called with a root hub endpoint (or an endpoint that wasn't added
+	 * with xhci_add_endpoint()
+	 */
+	if (!ep->hcpriv)
+		return;
+	ep_index = xhci_get_endpoint_index(&ep->desc);
+	virt_ep = &xhci->devs[udev->slot_id]->eps[ep_index];
+	if (!virt_ep->stopped_td) {
+		xhci_dbg(xhci, "Endpoint 0x%x not halted, refusing to reset.\n",
+				ep->desc.bEndpointAddress);
+		return;
+	}
+	if (usb_endpoint_xfer_control(&ep->desc)) {
+		xhci_dbg(xhci, "Control endpoint stall already handled.\n");
+		return;
+	}
+
+	xhci_dbg(xhci, "Queueing reset endpoint command\n");
+	spin_lock_irqsave(&xhci->lock, flags);
+	ret = xhci_queue_reset_ep(xhci, udev->slot_id, ep_index);
+	/*
+	 * Can't change the ring dequeue pointer until it's transitioned to the
+	 * stopped state, which is only upon a successful reset endpoint
+	 * command.  Better hope that last command worked!
+	 */
+	if (!ret) {
+		xhci_cleanup_stalled_ring(xhci, udev, ep_index);
+		kfree(virt_ep->stopped_td);
+		xhci_ring_cmd_db(xhci);
+	}
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	if (ret)
+		xhci_warn(xhci, "FIXME allocate a new ring segment\n");
+}
+
+/*
+ * This submits a Reset Device Command, which will set the device state to 0,
+ * set the device address to 0, and disable all the endpoints except the default
+ * control endpoint.  The USB core should come back and call
+ * xhci_address_device(), and then re-set up the configuration.  If this is
+ * called because of a usb_reset_and_verify_device(), then the old alternate
+ * settings will be re-installed through the normal bandwidth allocation
+ * functions.
+ *
+ * Wait for the Reset Device command to finish.  Remove all structures
+ * associated with the endpoints that were disabled.  Clear the input device
+ * structure?  Cache the rings?  Reset the control endpoint 0 max packet size?
+ */
+int xhci_reset_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	int ret, i;
+	unsigned long flags;
+	struct xhci_hcd *xhci;
+	unsigned int slot_id;
+	struct xhci_virt_device *virt_dev;
+	struct xhci_command *reset_device_cmd;
+	int timeleft;
+	int last_freed_endpoint;
+
+	ret = xhci_check_args(hcd, udev, NULL, 0, __func__);
+	if (ret <= 0)
+		return ret;
+	xhci = hcd_to_xhci(hcd);
+	slot_id = udev->slot_id;
+	virt_dev = xhci->devs[slot_id];
+	if (!virt_dev) {
+		xhci_dbg(xhci, "%s called with invalid slot ID %u\n",
+				__func__, slot_id);
+		return -EINVAL;
+	}
+
+	xhci_dbg(xhci, "Resetting device with slot ID %u\n", slot_id);
+	/* Allocate the command structure that holds the struct completion.
+	 * Assume we're in process context, since the normal device reset
+	 * process has to wait for the device anyway.  Storage devices are
+	 * reset as part of error handling, so use GFP_NOIO instead of
+	 * GFP_KERNEL.
+	 */
+	reset_device_cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO);
+	if (!reset_device_cmd) {
+		xhci_dbg(xhci, "Couldn't allocate command structure.\n");
+		return -ENOMEM;
+	}
+
+	/* Attempt to submit the Reset Device command to the command ring */
+	spin_lock_irqsave(&xhci->lock, flags);
+	reset_device_cmd->command_trb = xhci->cmd_ring->enqueue;
+	list_add_tail(&reset_device_cmd->cmd_list, &virt_dev->cmd_list);
+	ret = xhci_queue_reset_device(xhci, slot_id);
+	if (ret) {
+		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
+		list_del(&reset_device_cmd->cmd_list);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		goto command_cleanup;
+	}
+	xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	/* Wait for the Reset Device command to finish */
+	timeleft = wait_for_completion_interruptible_timeout(
+			reset_device_cmd->completion,
+			USB_CTRL_SET_TIMEOUT);
+	if (timeleft <= 0) {
+		xhci_warn(xhci, "%s while waiting for reset device command\n",
+				timeleft == 0 ? "Timeout" : "Signal");
+		spin_lock_irqsave(&xhci->lock, flags);
+		/* The timeout might have raced with the event ring handler, so
+		 * only delete from the list if the item isn't poisoned.
+		 */
+		if (reset_device_cmd->cmd_list.next != LIST_POISON1)
+			list_del(&reset_device_cmd->cmd_list);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		ret = -ETIME;
+		goto command_cleanup;
+	}
+
+	/* The Reset Device command can't fail, according to the 0.95/0.96 spec,
+	 * unless we tried to reset a slot ID that wasn't enabled,
+	 * or the device wasn't in the addressed or configured state.
+	 */
+	ret = reset_device_cmd->status;
+	switch (ret) {
+	case COMP_EBADSLT: /* 0.95 completion code for bad slot ID */
+	case COMP_CTX_STATE: /* 0.96 completion code for same thing */
+		xhci_info(xhci, "Can't reset device (slot ID %u) in %s state\n",
+				slot_id,
+				xhci_get_slot_state(xhci, virt_dev->out_ctx));
+		xhci_info(xhci, "Not freeing device rings.\n");
+		/* Don't treat this as an error.  May change my mind later. */
+		ret = 0;
+		goto command_cleanup;
+	case COMP_SUCCESS:
+		xhci_dbg(xhci, "Successful reset device command.\n");
+		break;
+	default:
+		if (xhci_is_vendor_info_code(xhci, ret))
+			break;
+		xhci_warn(xhci, "Unknown completion code %u for "
+				"reset device command.\n", ret);
+		ret = -EINVAL;
+		goto command_cleanup;
+	}
+
+	/* Everything but endpoint 0 is disabled, so free or cache the rings. */
+	last_freed_endpoint = 1;
+	for (i = 1; i < 31; ++i) {
+		if (!virt_dev->eps[i].ring)
+			continue;
+		xhci_free_or_cache_endpoint_ring(xhci, virt_dev, i);
+		last_freed_endpoint = i;
+	}
+	xhci_dbg(xhci, "Output context after successful reset device cmd:\n");
+	xhci_dbg_ctx(xhci, virt_dev->out_ctx, last_freed_endpoint);
+	ret = 0;
+
+command_cleanup:
+	xhci_free_command(xhci, reset_device_cmd);
+	return ret;
+}
+
+/*
+ * At this point, the struct usb_device is about to go away, the device has
+ * disconnected, and all traffic has been stopped and the endpoints have been
+ * disabled.  Free any HC data structures associated with that device.
+ */
+void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	struct xhci_virt_device *virt_dev;
+	unsigned long flags;
+	u32 state;
+	int i;
+
+	if (udev->slot_id == 0)
+		return;
+	virt_dev = xhci->devs[udev->slot_id];
+	if (!virt_dev)
+		return;
+
+	/* Stop any wayward timer functions (which may grab the lock) */
+	for (i = 0; i < 31; ++i) {
+		virt_dev->eps[i].ep_state &= ~EP_HALT_PENDING;
+		del_timer_sync(&virt_dev->eps[i].stop_cmd_timer);
+	}
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	/* Don't disable the slot if the host controller is dead. */
+	state = xhci_readl(xhci, &xhci->op_regs->status);
+	if (state == 0xffffffff || (xhci->xhc_state & XHCI_STATE_DYING)) {
+		xhci_free_virt_device(xhci, udev->slot_id);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return;
+	}
+
+	if (xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id)) {
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
+		return;
+	}
+	xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+	/*
+	 * Event command completion handler will free any data structures
+	 * associated with the slot.  XXX Can free sleep?
+	 */
+}
+
+/*
+ * Returns 0 if the xHC ran out of device slots, the Enable Slot command
+ * timed out, or allocating memory failed.  Returns 1 on success.
+ */
+int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	unsigned long flags;
+	int timeleft;
+	int ret;
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	ret = xhci_queue_slot_control(xhci, TRB_ENABLE_SLOT, 0);
+	if (ret) {
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
+		return 0;
+	}
+	xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	/* XXX: how much time for xHC slot assignment? */
+	timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev,
+			USB_CTRL_SET_TIMEOUT);
+	if (timeleft <= 0) {
+		xhci_warn(xhci, "%s while waiting for a slot\n",
+				timeleft == 0 ? "Timeout" : "Signal");
+		/* FIXME cancel the enable slot request */
+		return 0;
+	}
+
+	if (!xhci->slot_id) {
+		xhci_err(xhci, "Error while assigning device slot ID\n");
+		return 0;
+	}
+	/* xhci_alloc_virt_device() does not touch rings; no need to lock */
+	if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_KERNEL)) {
+		/* Disable slot, if we can do it without mem alloc */
+		xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n");
+		spin_lock_irqsave(&xhci->lock, flags);
+		if (!xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id))
+			xhci_ring_cmd_db(xhci);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return 0;
+	}
+	udev->slot_id = xhci->slot_id;
+	/* Is this a LS or FS device under a HS hub? */
+	/* Hub or peripherial? */
+	return 1;
+}
+
+/*
+ * Issue an Address Device command (which will issue a SetAddress request to
+ * the device).
+ * We should be protected by the usb_address0_mutex in khubd's hub_port_init, so
+ * we should only issue and wait on one address command at the same time.
+ *
+ * We add one to the device address issued by the hardware because the USB core
+ * uses address 1 for the root hubs (even though they're not really devices).
+ */
+int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+	unsigned long flags;
+	int timeleft;
+	struct xhci_virt_device *virt_dev;
+	int ret = 0;
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	struct xhci_slot_ctx *slot_ctx;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	u64 temp_64;
+
+	if (!udev->slot_id) {
+		xhci_dbg(xhci, "Bad Slot ID %d\n", udev->slot_id);
+		return -EINVAL;
+	}
+
+	virt_dev = xhci->devs[udev->slot_id];
+
+	/* If this is a Set Address to an unconfigured device, setup ep 0 */
+	if (!udev->config)
+		xhci_setup_addressable_virt_dev(xhci, udev);
+	/* Otherwise, assume the core has the device configured how it wants */
+	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
+	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	ret = xhci_queue_address_device(xhci, virt_dev->in_ctx->dma,
+					udev->slot_id);
+	if (ret) {
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
+		return ret;
+	}
+	xhci_ring_cmd_db(xhci);
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	/* ctrl tx can take up to 5 sec; XXX: need more time for xHC? */
+	timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev,
+			USB_CTRL_SET_TIMEOUT);
+	/* FIXME: From section 4.3.4: "Software shall be responsible for timing
+	 * the SetAddress() "recovery interval" required by USB and aborting the
+	 * command on a timeout.
+	 */
+	if (timeleft <= 0) {
+		xhci_warn(xhci, "%s while waiting for a slot\n",
+				timeleft == 0 ? "Timeout" : "Signal");
+		/* FIXME cancel the address device command */
+		return -ETIME;
+	}
+
+	switch (virt_dev->cmd_status) {
+	case COMP_CTX_STATE:
+	case COMP_EBADSLT:
+		xhci_err(xhci, "Setup ERROR: address device command for slot %d.\n",
+				udev->slot_id);
+		ret = -EINVAL;
+		break;
+	case COMP_TX_ERR:
+		dev_warn(&udev->dev, "Device not responding to set address.\n");
+		ret = -EPROTO;
+		break;
+	case COMP_SUCCESS:
+		xhci_dbg(xhci, "Successful Address Device command\n");
+		break;
+	default:
+		xhci_err(xhci, "ERROR: unexpected command completion "
+				"code 0x%x.\n", virt_dev->cmd_status);
+		xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
+		xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
+		ret = -EINVAL;
+		break;
+	}
+	if (ret) {
+		return ret;
+	}
+	temp_64 = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
+	xhci_dbg(xhci, "Op regs DCBAA ptr = %#016llx\n", temp_64);
+	xhci_dbg(xhci, "Slot ID %d dcbaa entry @%p = %#016llx\n",
+			udev->slot_id,
+			&xhci->dcbaa->dev_context_ptrs[udev->slot_id],
+			(unsigned long long)
+				xhci->dcbaa->dev_context_ptrs[udev->slot_id]);
+	xhci_dbg(xhci, "Output Context DMA address = %#08llx\n",
+			(unsigned long long)virt_dev->out_ctx->dma);
+	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
+	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
+	xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
+	xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
+	/*
+	 * USB core uses address 1 for the roothubs, so we add one to the
+	 * address given back to us by the HC.
+	 */
+	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
+	udev->devnum = (slot_ctx->dev_state & DEV_ADDR_MASK) + 1;
+	/* Zero the input context control for later use */
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
+	ctrl_ctx->add_flags = 0;
+	ctrl_ctx->drop_flags = 0;
+
+	xhci_dbg(xhci, "Device address = %d\n", udev->devnum);
+	/* XXX Meh, not sure if anyone else but choose_address uses this. */
+	set_bit(udev->devnum, udev->bus->devmap.devicemap);
+
+	return 0;
+}
+
+/* Once a hub descriptor is fetched for a device, we need to update the xHC's
+ * internal data structures for the device.
+ */
+int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
+			struct usb_tt *tt, gfp_t mem_flags)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	struct xhci_virt_device *vdev;
+	struct xhci_command *config_cmd;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	struct xhci_slot_ctx *slot_ctx;
+	unsigned long flags;
+	unsigned think_time;
+	int ret;
+
+	/* Ignore root hubs */
+	if (!hdev->parent)
+		return 0;
+
+	vdev = xhci->devs[hdev->slot_id];
+	if (!vdev) {
+		xhci_warn(xhci, "Cannot update hub desc for unknown device.\n");
+		return -EINVAL;
+	}
+	config_cmd = xhci_alloc_command(xhci, true, true, mem_flags);
+	if (!config_cmd) {
+		xhci_dbg(xhci, "Could not allocate xHCI command structure.\n");
+		return -ENOMEM;
+	}
+
+	spin_lock_irqsave(&xhci->lock, flags);
+	xhci_slot_copy(xhci, config_cmd->in_ctx, vdev->out_ctx);
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, config_cmd->in_ctx);
+	ctrl_ctx->add_flags |= SLOT_FLAG;
+	slot_ctx = xhci_get_slot_ctx(xhci, config_cmd->in_ctx);
+	slot_ctx->dev_info |= DEV_HUB;
+	if (tt->multi)
+		slot_ctx->dev_info |= DEV_MTT;
+	if (xhci->hci_version > 0x95) {
+		xhci_dbg(xhci, "xHCI version %x needs hub "
+				"TT think time and number of ports\n",
+				(unsigned int) xhci->hci_version);
+		slot_ctx->dev_info2 |= XHCI_MAX_PORTS(hdev->maxchild);
+		/* Set TT think time - convert from ns to FS bit times.
+		 * 0 = 8 FS bit times, 1 = 16 FS bit times,
+		 * 2 = 24 FS bit times, 3 = 32 FS bit times.
+		 */
+		think_time = tt->think_time;
+		if (think_time != 0)
+			think_time = (think_time / 666) - 1;
+		slot_ctx->tt_info |= TT_THINK_TIME(think_time);
+	} else {
+		xhci_dbg(xhci, "xHCI version %x doesn't need hub "
+				"TT think time or number of ports\n",
+				(unsigned int) xhci->hci_version);
+	}
+	slot_ctx->dev_state = 0;
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	xhci_dbg(xhci, "Set up %s for hub device.\n",
+			(xhci->hci_version > 0x95) ?
+			"configure endpoint" : "evaluate context");
+	xhci_dbg(xhci, "Slot %u Input Context:\n", hdev->slot_id);
+	xhci_dbg_ctx(xhci, config_cmd->in_ctx, 0);
+
+	/* Issue and wait for the configure endpoint or
+	 * evaluate context command.
+	 */
+	if (xhci->hci_version > 0x95)
+		ret = xhci_configure_endpoint(xhci, hdev, config_cmd,
+				false, false);
+	else
+		ret = xhci_configure_endpoint(xhci, hdev, config_cmd,
+				true, false);
+
+	xhci_dbg(xhci, "Slot %u Output Context:\n", hdev->slot_id);
+	xhci_dbg_ctx(xhci, vdev->out_ctx, 0);
+
+	xhci_free_command(xhci, config_cmd);
+	return ret;
+}
+
+int xhci_get_frame(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	/* EHCI mods by the periodic size.  Why? */
+	return xhci_readl(xhci, &xhci->run_regs->microframe_index) >> 3;
+}
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_LICENSE("GPL");
+
+static int __init xhci_hcd_init(void)
+{
+#ifdef CONFIG_PCI
+	int retval = 0;
+
+	retval = xhci_register_pci();
+
+	if (retval < 0) {
+		printk(KERN_DEBUG "Problem registering PCI driver.");
+		return retval;
+	}
+#endif
+	/*
+	 * Check the compiler generated sizes of structures that must be laid
+	 * out in specific ways for hardware access.
+	 */
+	BUILD_BUG_ON(sizeof(struct xhci_doorbell_array) != 256*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_slot_ctx) != 8*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_ep_ctx) != 8*32/8);
+	/* xhci_device_control has eight fields, and also
+	 * embeds one xhci_slot_ctx and 31 xhci_ep_ctx
+	 */
+	BUILD_BUG_ON(sizeof(struct xhci_stream_ctx) != 4*32/8);
+	BUILD_BUG_ON(sizeof(union xhci_trb) != 4*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_erst_entry) != 4*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_cap_regs) != 7*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_intr_reg) != 8*32/8);
+	/* xhci_run_regs has eight fields and embeds 128 xhci_intr_regs */
+	BUILD_BUG_ON(sizeof(struct xhci_run_regs) != (8+8*128)*32/8);
+	BUILD_BUG_ON(sizeof(struct xhci_doorbell_array) != 256*32/8);
+	return 0;
+}
+module_init(xhci_hcd_init);
+
+static void __exit xhci_hcd_cleanup(void)
+{
+#ifdef CONFIG_PCI
+	xhci_unregister_pci();
+#endif
+}
+module_exit(xhci_hcd_cleanup);