Merge tag 'usb-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
"Here are a number of USB driver fixes for 3.12-rc3.

These are all for host controller issues that have been reported, and
there's a fix for an annoying error message that gets printed every
time you remove a USB 3 device from the system that's been bugging me
for a while"

* tag 'usb-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: dwc3: add support for Merrifield
USB: fsl/ehci: fix failure of checking PHY_CLK_VALID during reinitialization
USB: Fix breakage in ffs_fs_mount()
fsl/usb: Resolve PHY_CLK_VLD instability issue for ULPI phy
usb/core/devio.c: Don't reject control message to endpoint with wrong direction bit
usb: chipidea: USB_CHIPIDEA should depend on HAS_DMA
usb: chipidea: udc: free pending TD at removal procedure
usb: chipidea: imx: Add usb_phy_shutdown at probe's error path
usb: chipidea: Fix memleak for ci->hw_bank.regmap when removal
usb: chipidea: udc: fix the oops after rmmod gadget
USB: fix PM config symbol in uhci-hcd, ehci-hcd, and xhci-hcd
USB: OHCI: accept very late isochronous URBs
USB: UHCI: accept very late isochronous URBs
USB: iMX21: accept very late isochronous URBs
usbcore: check usb device's state before sending a Set SEL control transfer
xhci: Fix race between ep halt and URB cancellation
usb: Fix xHCI host issues on remote wakeup.
xhci: Ensure a command structure points to the correct trb on the command ring
xhci: Fix oops happening after address device timeout

drivers/usb/chipidea/Kconfig

···
 config USB_CHIPIDEA
 	tristate "ChipIdea Highspeed Dual Role Controller"
-	depends on (USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || (!USB_EHCI_HCD && USB_GADGET)
+	depends on ((USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || (!USB_EHCI_HCD && USB_GADGET)) && HAS_DMA
 	help
 	  Say Y here if your system has a dual role high speed USB
 	  controller based on ChipIdea silicon IP. Currently, only the

drivers/usb/chipidea/ci_hdrc_imx.c

···
 		if (ret) {
 			dev_err(&pdev->dev, "usbmisc init failed, ret=%d\n",
 					ret);
-			goto err_clk;
+			goto err_phy;
 		}
 	}
 
···
 		dev_err(&pdev->dev,
 			"Can't register ci_hdrc platform device, err=%d\n",
 			ret);
-		goto err_clk;
+		goto err_phy;
 	}
 
 	if (data->usbmisc_data) {
···
 
 disable_device:
 	ci_hdrc_remove_device(data->ci_pdev);
+err_phy:
+	if (data->phy)
+		usb_phy_shutdown(data->phy);
 err_clk:
 	clk_disable_unprepare(data->clk);
 	return ret;

drivers/usb/chipidea/core.c

···
 	dbg_remove_files(ci);
 	free_irq(ci->irq, ci);
 	ci_role_destroy(ci);
+	kfree(ci->hw_bank.regmap);
 
 	return 0;
 }

drivers/usb/chipidea/udc.c

···
 	for (i = 0; i < ci->hw_ep_max; i++) {
 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
 
+		if (hwep->pending_td)
+			free_pending_td(hwep);
 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
 	}
 }
···
 		if (ci->platdata->notify_event)
 			ci->platdata->notify_event(ci,
 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
-		ci->driver = NULL;
 		spin_unlock_irqrestore(&ci->lock, flags);
 		_gadget_stop_activity(&ci->gadget);
 		spin_lock_irqsave(&ci->lock, flags);
 		pm_runtime_put(&ci->gadget.dev);
 	}
 
+	ci->driver = NULL;
 	spin_unlock_irqrestore(&ci->lock, flags);
 
 	return 0;

drivers/usb/core/devio.c

···
 		if ((index & ~USB_DIR_IN) == 0)
 			return 0;
 		ret = findintfep(ps->dev, index);
+		if (ret < 0) {
+			/*
+			 * Some not fully compliant Win apps seem to get
+			 * index wrong and have the endpoint number here
+			 * rather than the endpoint address (with the
+			 * correct direction). Win does let this through,
+			 * so we'll not reject it here but leave it to
+			 * the device to not break KVM. But we warn.
+			 */
+			ret = findintfep(ps->dev, index ^ 0x80);
+			if (ret >= 0)
+				dev_info(&ps->dev->dev,
+					"%s: process %i (%s) requesting ep %02x but needs %02x\n",
+					__func__, task_pid_nr(current),
+					current->comm, index, index ^ 0x80);
+		}
 		if (ret >= 0)
 			ret = checkintf(ps, ret);
 		break;

drivers/usb/core/hub.c

···
 	unsigned long long u2_pel;
 	int ret;
 
+	if (udev->state != USB_STATE_CONFIGURED)
+		return 0;
+
 	/* Convert SEL and PEL stored in ns to us */
 	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
 	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);

drivers/usb/dwc3/dwc3-pci.c

···
 #define PCI_VENDOR_ID_SYNOPSYS		0x16c3
 #define PCI_DEVICE_ID_SYNOPSYS_HAPSUSB3	0xabcd
 #define PCI_DEVICE_ID_INTEL_BYT		0x0f37
+#define PCI_DEVICE_ID_INTEL_MRFLD	0x119e
 
 struct dwc3_pci {
 	struct device		*dev;
···
 				PCI_DEVICE_ID_SYNOPSYS_HAPSUSB3),
 	},
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BYT), },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_MRFLD), },
 	{  }	/* Terminating Entry */
 };
 MODULE_DEVICE_TABLE(pci, dwc3_pci_id_table);

drivers/usb/gadget/f_fs.c

···
 	struct ffs_file_perms perms;
 	umode_t root_mode;
 	const char *dev_name;
-	union {
-		/* set by ffs_fs_mount(), read by ffs_sb_fill() */
-		void *private_data;
-		/* set by ffs_sb_fill(), read by ffs_fs_mount */
-		struct ffs_data *ffs_data;
-	};
+	struct ffs_data *ffs_data;
 };
 
 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
 {
 	struct ffs_sb_fill_data *data = _data;
 	struct inode	*inode;
-	struct ffs_data	*ffs;
+	struct ffs_data	*ffs = data->ffs_data;
 
 	ENTER();
 
-	/* Initialise data */
-	ffs = ffs_data_new();
-	if (unlikely(!ffs))
-		goto Enomem;
-
 	ffs->sb              = sb;
-	ffs->dev_name        = kstrdup(data->dev_name, GFP_KERNEL);
-	if (unlikely(!ffs->dev_name))
-		goto Enomem;
-	ffs->file_perms      = data->perms;
-	ffs->private_data    = data->private_data;
-
-	/* used by the caller of this function */
-	data->ffs_data       = ffs;
-
+	data->ffs_data       = NULL;
 	sb->s_fs_info        = ffs;
 	sb->s_blocksize      = PAGE_CACHE_SIZE;
 	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
···
 				  &data->perms);
 	sb->s_root = d_make_root(inode);
 	if (unlikely(!sb->s_root))
-		goto Enomem;
+		return -ENOMEM;
 
 	/* EP0 file */
 	if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
 					 &ffs_ep0_operations, NULL)))
-		goto Enomem;
+		return -ENOMEM;
 
 	return 0;
-
-Enomem:
-	return -ENOMEM;
 }
 
 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
···
 	struct dentry *rv;
 	int ret;
 	void *ffs_dev;
+	struct ffs_data	*ffs;
 
 	ENTER();
 
···
 	if (unlikely(ret < 0))
 		return ERR_PTR(ret);
 
+	ffs = ffs_data_new();
+	if (unlikely(!ffs))
+		return ERR_PTR(-ENOMEM);
+	ffs->file_perms = data.perms;
+
+	ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
+	if (unlikely(!ffs->dev_name)) {
+		ffs_data_put(ffs);
+		return ERR_PTR(-ENOMEM);
+	}
+
 	ffs_dev = functionfs_acquire_dev_callback(dev_name);
-	if (IS_ERR(ffs_dev))
-		return ffs_dev;
+	if (IS_ERR(ffs_dev)) {
+		ffs_data_put(ffs);
+		return ERR_CAST(ffs_dev);
+	}
+	ffs->private_data = ffs_dev;
+	data.ffs_data = ffs;
 
-	data.dev_name = dev_name;
-	data.private_data = ffs_dev;
 	rv = mount_nodev(t, flags, &data, ffs_sb_fill);
-
-	/* data.ffs_data is set by ffs_sb_fill */
-	if (IS_ERR(rv))
+	if (IS_ERR(rv) && data.ffs_data) {
 		functionfs_release_dev_callback(data.ffs_data);
-
+		ffs_data_put(data.ffs_data);
+	}
 	return rv;
 }
 

drivers/usb/host/ehci-fsl.c

···
 	}
 
 	/* Enable USB controller, 83xx or 8536 */
-	if (pdata->have_sysif_regs)
+	if (pdata->have_sysif_regs && pdata->controller_ver < FSL_USB_VER_1_6)
 		setbits32(hcd->regs + FSL_SOC_USB_CTRL, 0x4);
 
 	/* Don't need to set host mode here. It will be done by tdi_reset() */
···
 	case FSL_USB2_PHY_ULPI:
 		if (pdata->have_sysif_regs && pdata->controller_ver) {
 			/* controller version 1.6 or above */
+			clrbits32(non_ehci + FSL_SOC_USB_CTRL, UTMI_PHY_EN);
 			setbits32(non_ehci + FSL_SOC_USB_CTRL,
-					ULPI_PHY_CLK_SEL);
-			/*
-			 * Due to controller issue of PHY_CLK_VALID in ULPI
-			 * mode, we set USB_CTRL_USB_EN before checking
-			 * PHY_CLK_VALID, otherwise PHY_CLK_VALID doesn't work.
-			 */
-			clrsetbits_be32(non_ehci + FSL_SOC_USB_CTRL,
-					UTMI_PHY_EN, USB_CTRL_USB_EN);
+				ULPI_PHY_CLK_SEL | USB_CTRL_USB_EN);
 		}
 		portsc |= PORT_PTS_ULPI;
 		break;
···
 	if (pdata->have_sysif_regs && pdata->controller_ver &&
 	    (phy_mode == FSL_USB2_PHY_ULPI)) {
 		/* check PHY_CLK_VALID to get phy clk valid */
-		if (!spin_event_timeout(in_be32(non_ehci + FSL_SOC_USB_CTRL) &
-				PHY_CLK_VALID, FSL_USB_PHY_CLK_TIMEOUT, 0)) {
+		if (!(spin_event_timeout(in_be32(non_ehci + FSL_SOC_USB_CTRL) &
+				PHY_CLK_VALID, FSL_USB_PHY_CLK_TIMEOUT, 0) ||
+				in_be32(non_ehci + FSL_SOC_USB_PRICTRL))) {
 			printk(KERN_WARNING "fsl-ehci: USB PHY clock invalid\n");
 			return -EINVAL;
 		}

drivers/usb/host/ehci-pci.c

···
 	.remove =	usb_hcd_pci_remove,
 	.shutdown = 	usb_hcd_pci_shutdown,
 
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
 	.driver =	{
 		.pm =	&usb_hcd_pci_pm_ops
 	},

drivers/usb/host/imx21-hcd.c

···
 			i = DIV_ROUND_UP(wrap_frame(
 					cur_frame - urb->start_frame),
 					urb->interval);
-			if (urb->transfer_flags & URB_ISO_ASAP) {
+
+			/* Treat underruns as if URB_ISO_ASAP was set */
+			if ((urb->transfer_flags & URB_ISO_ASAP) ||
+					i >= urb->number_of_packets) {
 				urb->start_frame = wrap_frame(urb->start_frame
 						+ i * urb->interval);
 				i = 0;
-			} else if (i >= urb->number_of_packets) {
-				ret = -EXDEV;
-				goto alloc_dmem_failed;
 			}
 		}
 	}

drivers/usb/host/ohci-hcd.c

···
 			frame &= ~(ed->interval - 1);
 			frame |= ed->branch;
 			urb->start_frame = frame;
+			ed->last_iso = frame + ed->interval * (size - 1);
 		}
 	} else if (ed->type == PIPE_ISOCHRONOUS) {
 		u16	next = ohci_frame_no(ohci) + 1;
 		u16	frame = ed->last_iso + ed->interval;
+		u16	length = ed->interval * (size - 1);
 
 		/* Behind the scheduling threshold? */
 		if (unlikely(tick_before(frame, next))) {
 
-			/* USB_ISO_ASAP: Round up to the first available slot */
+			/* URB_ISO_ASAP: Round up to the first available slot */
 			if (urb->transfer_flags & URB_ISO_ASAP) {
 				frame += (next - frame + ed->interval - 1) &
 						-ed->interval;
 
 			/*
-			 * Not ASAP: Use the next slot in the stream.  If
-			 * the entire URB falls before the threshold, fail.
+			 * Not ASAP: Use the next slot in the stream,
+			 * no matter what.
 			 */
 			} else {
-				if (tick_before(frame + ed->interval *
-					(urb->number_of_packets - 1), next)) {
-					retval = -EXDEV;
-					usb_hcd_unlink_urb_from_ep(hcd, urb);
-					goto fail;
-				}
-
 				/*
 				 * Some OHCI hardware doesn't handle late TDs
 				 * correctly.  After retiring them it proceeds
···
 				urb_priv->td_cnt = DIV_ROUND_UP(
 						(u16) (next - frame),
 						ed->interval);
+				if (urb_priv->td_cnt >= urb_priv->length) {
+					++urb_priv->td_cnt;	/* Mark it */
+					ohci_dbg(ohci, "iso underrun %p (%u+%u < %u)\n",
+							urb, frame, length,
+							next);
+				}
 			}
 		}
 		urb->start_frame = frame;
+		ed->last_iso = frame + length;
 	}
 
 	/* fill the TDs and link them to the ed; and

drivers/usb/host/ohci-q.c

···
 __releases(ohci->lock)
 __acquires(ohci->lock)
 {
-	 struct device *dev = ohci_to_hcd(ohci)->self.controller;
+	struct device *dev = ohci_to_hcd(ohci)->self.controller;
+	struct usb_host_endpoint *ep = urb->ep;
+	struct urb_priv *urb_priv;
+
 	// ASSERT (urb->hcpriv != 0);
 
+ restart:
 	urb_free_priv (ohci, urb->hcpriv);
 	urb->hcpriv = NULL;
 	if (likely(status == -EINPROGRESS))
···
 			&& ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0) {
 		ohci->hc_control &= ~(OHCI_CTRL_PLE|OHCI_CTRL_IE);
 		ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
+	}
+
+	/*
+	 * An isochronous URB that is sumitted too late won't have any TDs
+	 * (marked by the fact that the td_cnt value is larger than the
+	 * actual number of TDs).  If the next URB on this endpoint is like
+	 * that, give it back now.
+	 */
+	if (!list_empty(&ep->urb_list)) {
+		urb = list_first_entry(&ep->urb_list, struct urb, urb_list);
+		urb_priv = urb->hcpriv;
+		if (urb_priv->td_cnt > urb_priv->length) {
+			status = 0;
+			goto restart;
+		}
 	}
 }
 
···
 		td->hwCBP = cpu_to_hc32 (ohci, data & 0xFFFFF000);
 		*ohci_hwPSWp(ohci, td, 0) = cpu_to_hc16 (ohci,
 						(data & 0x0FFF) | 0xE000);
-		td->ed->last_iso = info & 0xffff;
 	} else {
 		td->hwCBP = cpu_to_hc32 (ohci, data);
 	}
···
 			urb_priv->td_cnt++;
 
 			/* if URB is done, clean up */
-			if (urb_priv->td_cnt == urb_priv->length) {
+			if (urb_priv->td_cnt >= urb_priv->length) {
 				modified = completed = 1;
 				finish_urb(ohci, urb, 0);
 			}
···
 	urb_priv->td_cnt++;
 
 	/* If all this urb's TDs are done, call complete() */
-	if (urb_priv->td_cnt == urb_priv->length)
+	if (urb_priv->td_cnt >= urb_priv->length)
 		finish_urb(ohci, urb, status);
 
 	/* clean schedule:  unlink EDs that are no longer busy */

drivers/usb/host/uhci-pci.c

···
 	.remove =	usb_hcd_pci_remove,
 	.shutdown =	uhci_shutdown,
 
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
 	.driver =	{
 		.pm =	&usb_hcd_pci_pm_ops
 	},

drivers/usb/host/uhci-q.c

···
 		}
 
 		/* Fell behind? */
-		if (uhci_frame_before_eq(frame, next)) {
+		if (!uhci_frame_before_eq(next, frame)) {
 
 			/* USB_ISO_ASAP: Round up to the first available slot */
 			if (urb->transfer_flags & URB_ISO_ASAP)
···
 						-qh->period;
 
 			/*
-			 * Not ASAP: Use the next slot in the stream.  If
-			 * the entire URB falls before the threshold, fail.
+			 * Not ASAP: Use the next slot in the stream,
+			 * no matter what.
 			 */
 			else if (!uhci_frame_before_eq(next,
 					frame + (urb->number_of_packets - 1) *
 						qh->period))
-				return -EXDEV;
+				dev_dbg(uhci_dev(uhci), "iso underrun %p (%u+%u < %u)\n",
+						urb, frame,
+						(urb->number_of_packets - 1) *
+							qh->period,
+						next);
 		}
 	}
 

drivers/usb/host/xhci-hub.c

···
 		if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue)
 			xhci_queue_stop_endpoint(xhci, slot_id, i, suspend);
 	}
-	cmd->command_trb = xhci->cmd_ring->enqueue;
+	cmd->command_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 	list_add_tail(&cmd->cmd_list, &virt_dev->cmd_list);
 	xhci_queue_stop_endpoint(xhci, slot_id, 0, suspend);
 	xhci_ring_cmd_db(xhci);
···
  *  - Mark a port as being done with device resume,
  *    and ring the endpoint doorbells.
  *  - Stop the Synopsys redriver Compliance Mode polling.
+ *  - Drop and reacquire the xHCI lock, in order to wait for port resume.
  */
 static u32 xhci_get_port_status(struct usb_hcd *hcd,
 		struct xhci_bus_state *bus_state,
 		__le32 __iomem **port_array,
-		u16 wIndex, u32 raw_port_status)
+		u16 wIndex, u32 raw_port_status,
+		unsigned long flags)
+	__releases(&xhci->lock)
+	__acquires(&xhci->lock)
 {
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 	u32 status = 0;
···
 			return 0xffffffff;
 		if (time_after_eq(jiffies,
 					bus_state->resume_done[wIndex])) {
+			int time_left;
+
 			xhci_dbg(xhci, "Resume USB2 port %d\n",
 					wIndex + 1);
 			bus_state->resume_done[wIndex] = 0;
 			clear_bit(wIndex, &bus_state->resuming_ports);
+
+			set_bit(wIndex, &bus_state->rexit_ports);
 			xhci_set_link_state(xhci, port_array, wIndex,
 					XDEV_U0);
-			xhci_dbg(xhci, "set port %d resume\n",
-					wIndex + 1);
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-					wIndex + 1);
-			if (!slot_id) {
-				xhci_dbg(xhci, "slot_id is zero\n");
-				return 0xffffffff;
+
+			spin_unlock_irqrestore(&xhci->lock, flags);
+			time_left = wait_for_completion_timeout(
+					&bus_state->rexit_done[wIndex],
+					msecs_to_jiffies(
+						XHCI_MAX_REXIT_TIMEOUT));
+			spin_lock_irqsave(&xhci->lock, flags);
+
+			if (time_left) {
+				slot_id = xhci_find_slot_id_by_port(hcd,
+						xhci, wIndex + 1);
+				if (!slot_id) {
+					xhci_dbg(xhci, "slot_id is zero\n");
+					return 0xffffffff;
+				}
+				xhci_ring_device(xhci, slot_id);
+			} else {
+				int port_status = xhci_readl(xhci,
+						port_array[wIndex]);
+				xhci_warn(xhci, "Port resume took longer than %i msec, port status = 0x%x\n",
+						XHCI_MAX_REXIT_TIMEOUT,
+						port_status);
+				status |= USB_PORT_STAT_SUSPEND;
+				clear_bit(wIndex, &bus_state->rexit_ports);
 			}
-			xhci_ring_device(xhci, slot_id);
+
 			bus_state->port_c_suspend |= 1 << wIndex;
 			bus_state->suspended_ports &= ~(1 << wIndex);
 		} else {
···
 			break;
 		}
 		status = xhci_get_port_status(hcd, bus_state, port_array,
-				wIndex, temp);
+				wIndex, temp, flags);
 		if (status == 0xffffffff)
 			goto error;
 

drivers/usb/host/xhci-mem.c

···
 	for (i = 0; i < USB_MAXCHILDREN; ++i) {
 		xhci->bus_state[0].resume_done[i] = 0;
 		xhci->bus_state[1].resume_done[i] = 0;
+		/* Only the USB 2.0 completions will ever be used. */
+		init_completion(&xhci->bus_state[1].rexit_done[i]);
 	}
 
 	if (scratchpad_alloc(xhci, flags))

drivers/usb/host/xhci-pci.c

···
 	/* suspend and resume implemented later */
 
 	.shutdown = 	usb_hcd_pci_shutdown,
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
 	.driver = {
 		.pm = &usb_hcd_pci_pm_ops
 	},

drivers/usb/host/xhci-ring.c

···
 	return TRB_TYPE_LINK_LE32(link->control);
 }
 
+union xhci_trb *xhci_find_next_enqueue(struct xhci_ring *ring)
+{
+	/* Enqueue pointer can be left pointing to the link TRB,
+	 * we must handle that
+	 */
+	if (TRB_TYPE_LINK_LE32(ring->enqueue->link.control))
+		return ring->enq_seg->next->trbs;
+	return ring->enqueue;
+}
+
 /* Updates trb to point to the next TRB in the ring, and updates seg if the next
  * TRB is in a new segment.  This does not skip over link TRBs, and it does not
  * effect the ring dequeue or enqueue pointers.
···
 		/* Otherwise ring the doorbell(s) to restart queued transfers */
 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
 	}
-	ep->stopped_td = NULL;
-	ep->stopped_trb = NULL;
+
+	/* Clear stopped_td and stopped_trb if endpoint is not halted */
+	if (!(ep->ep_state & EP_HALTED)) {
+		ep->stopped_td = NULL;
+		ep->stopped_trb = NULL;
+	}
 
 	/*
 	 * Drop the lock and complete the URBs in the cancelled TD list.
···
 			inc_deq(xhci, xhci->cmd_ring);
 			return;
 		}
+		/* There is no command to handle if we get a stop event when the
+		 * command ring is empty, event->cmd_trb points to the next
+		 * unset command
+		 */
+		if (xhci->cmd_ring->dequeue == xhci->cmd_ring->enqueue)
+			return;
 	}
 
 	switch (le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3])
···
 			bogus_port_status = true;
 			goto cleanup;
 		}
+	}
+
+	/*
+	 * Check to see if xhci-hub.c is waiting on RExit to U0 transition (or
+	 * RExit to a disconnect state).  If so, let the the driver know it's
+	 * out of the RExit state.
+	 */
+	if (!DEV_SUPERSPEED(temp) &&
+			test_and_clear_bit(faked_port_index,
+				&bus_state->rexit_ports)) {
+		complete(&bus_state->rexit_done[faked_port_index]);
+		bogus_port_status = true;
+		goto cleanup;
 	}
 
 	if (hcd->speed != HCD_USB3)

drivers/usb/host/xhci.c

···
 	if (command) {
 		cmd_completion = command->completion;
 		cmd_status = &command->status;
-		command->command_trb = xhci->cmd_ring->enqueue;
-
-		/* Enqueue pointer can be left pointing to the link TRB,
-		 * we must handle that
-		 */
-		if (TRB_TYPE_LINK_LE32(command->command_trb->link.control))
-			command->command_trb =
-				xhci->cmd_ring->enq_seg->next->trbs;
-
+		command->command_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 		list_add_tail(&command->cmd_list, &virt_dev->cmd_list);
 	} else {
 		cmd_completion = &virt_dev->cmd_completion;
···
 	}
 	init_completion(cmd_completion);
 
-	cmd_trb = xhci->cmd_ring->dequeue;
+	cmd_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 	if (!ctx_change)
 		ret = xhci_queue_configure_endpoint(xhci, in_ctx->dma,
 				udev->slot_id, must_succeed);
···
 
 	/* 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;
-
-	/* Enqueue pointer can be left pointing to the link TRB,
-	 * we must handle that
-	 */
-	if (TRB_TYPE_LINK_LE32(reset_device_cmd->command_trb->link.control))
-		reset_device_cmd->command_trb =
-			xhci->cmd_ring->enq_seg->next->trbs;
+	reset_device_cmd->command_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 
 	list_add_tail(&reset_device_cmd->cmd_list, &virt_dev->cmd_list);
 	ret = xhci_queue_reset_device(xhci, slot_id);
···
 	union xhci_trb *cmd_trb;
 
 	spin_lock_irqsave(&xhci->lock, flags);
-	cmd_trb = xhci->cmd_ring->dequeue;
+	cmd_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 	ret = xhci_queue_slot_control(xhci, TRB_ENABLE_SLOT, 0);
 	if (ret) {
 		spin_unlock_irqrestore(&xhci->lock, flags);
···
 				slot_ctx->dev_info >> 27);
 
 	spin_lock_irqsave(&xhci->lock, flags);
-	cmd_trb = xhci->cmd_ring->dequeue;
+	cmd_trb = xhci_find_next_enqueue(xhci->cmd_ring);
 	ret = xhci_queue_address_device(xhci, virt_dev->in_ctx->dma,
 					udev->slot_id);
 	if (ret) {

drivers/usb/host/xhci.h

···
 	unsigned long		resume_done[USB_MAXCHILDREN];
 	/* which ports have started to resume */
 	unsigned long		resuming_ports;
+	/* Which ports are waiting on RExit to U0 transition. */
+	unsigned long		rexit_ports;
+	struct completion	rexit_done[USB_MAXCHILDREN];
 };
+
+
+/*
+ * It can take up to 20 ms to transition from RExit to U0 on the
+ * Intel Lynx Point LP xHCI host.
+ */
+#define	XHCI_MAX_REXIT_TIMEOUT	(20 * 1000)
 
 static inline unsigned int hcd_index(struct usb_hcd *hcd)
 {
···
 		union xhci_trb *cmd_trb);
 void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id,
 		unsigned int ep_index, unsigned int stream_id);
+union xhci_trb *xhci_find_next_enqueue(struct xhci_ring *ring);
 
 /* xHCI roothub code */
 void xhci_set_link_state(struct xhci_hcd *xhci, __le32 __iomem **port_array,