1 files changed, 104 insertions, 43 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 5d7d4e951ea4..34cf4e165877 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -226,7 +226,8 @@ static int xhci_setup_msi(struct xhci_hcd *xhci)
 static int xhci_setup_msix(struct xhci_hcd *xhci)
 {
 	int i, ret = 0;
-	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+	struct usb_hcd *hcd = xhci_to_hcd(xhci);
+	struct pci_dev *pdev = to_pci_dev(hcd->self.controller);
 
 	/*
 	 * calculate number of msi-x vectors supported.
@@ -265,6 +266,7 @@ static int xhci_setup_msix(struct xhci_hcd *xhci)
 			goto disable_msix;
 	}
 
+	hcd->msix_enabled = 1;
 	return ret;
 
 disable_msix:
@@ -280,7 +282,8 @@ free_entries:
 /* 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);
+	struct usb_hcd *hcd = xhci_to_hcd(xhci);
+	struct pci_dev *pdev = to_pci_dev(hcd->self.controller);
 
 	xhci_free_irq(xhci);
 
@@ -292,6 +295,7 @@ static void xhci_cleanup_msix(struct xhci_hcd *xhci)
 		pci_disable_msi(pdev);
 	}
 
+	hcd->msix_enabled = 0;
 	return;
 }
 
@@ -508,9 +512,10 @@ void xhci_stop(struct usb_hcd *hcd)
 	spin_lock_irq(&xhci->lock);
 	xhci_halt(xhci);
 	xhci_reset(xhci);
-	xhci_cleanup_msix(xhci);
 	spin_unlock_irq(&xhci->lock);
 
+	xhci_cleanup_msix(xhci);
+
 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
 	/* Tell the event ring poll function not to reschedule */
 	xhci->zombie = 1;
@@ -544,9 +549,10 @@ void xhci_shutdown(struct usb_hcd *hcd)
 
 	spin_lock_irq(&xhci->lock);
 	xhci_halt(xhci);
-	xhci_cleanup_msix(xhci);
 	spin_unlock_irq(&xhci->lock);
 
+	xhci_cleanup_msix(xhci);
+
 	xhci_dbg(xhci, "xhci_shutdown completed - status = %x\n",
 		    xhci_readl(xhci, &xhci->op_regs->status));
 }
@@ -577,6 +583,65 @@ static void xhci_restore_registers(struct xhci_hcd *xhci)
 	xhci_write_64(xhci, xhci->s3.erst_base, &xhci->ir_set->erst_base);
 }
 
+static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci)
+{
+	u64	val_64;
+
+	/* step 2: initialize command ring buffer */
+	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
+	val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
+		(xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
+				      xhci->cmd_ring->dequeue) &
+		 (u64) ~CMD_RING_RSVD_BITS) |
+		xhci->cmd_ring->cycle_state;
+	xhci_dbg(xhci, "// Setting command ring address to 0x%llx\n",
+			(long unsigned long) val_64);
+	xhci_write_64(xhci, val_64, &xhci->op_regs->cmd_ring);
+}
+
+/*
+ * The whole command ring must be cleared to zero when we suspend the host.
+ *
+ * The host doesn't save the command ring pointer in the suspend well, so we
+ * need to re-program it on resume.  Unfortunately, the pointer must be 64-byte
+ * aligned, because of the reserved bits in the command ring dequeue pointer
+ * register.  Therefore, we can't just set the dequeue pointer back in the
+ * middle of the ring (TRBs are 16-byte aligned).
+ */
+static void xhci_clear_command_ring(struct xhci_hcd *xhci)
+{
+	struct xhci_ring *ring;
+	struct xhci_segment *seg;
+
+	ring = xhci->cmd_ring;
+	seg = ring->deq_seg;
+	do {
+		memset(seg->trbs, 0, SEGMENT_SIZE);
+		seg = seg->next;
+	} while (seg != ring->deq_seg);
+
+	/* Reset the software enqueue and dequeue pointers */
+	ring->deq_seg = ring->first_seg;
+	ring->dequeue = ring->first_seg->trbs;
+	ring->enq_seg = ring->deq_seg;
+	ring->enqueue = ring->dequeue;
+
+	/*
+	 * Ring is now zeroed, so the HW should look for change of ownership
+	 * when the cycle bit is set to 1.
+	 */
+	ring->cycle_state = 1;
+
+	/*
+	 * Reset the hardware dequeue pointer.
+	 * Yes, this will need to be re-written after resume, but we're paranoid
+	 * and want to make sure the hardware doesn't access bogus memory
+	 * because, say, the BIOS or an SMI started the host without changing
+	 * the command ring pointers.
+	 */
+	xhci_set_cmd_ring_deq(xhci);
+}
+
 /*
  * Stop HC (not bus-specific)
  *
@@ -588,6 +653,7 @@ int xhci_suspend(struct xhci_hcd *xhci)
 	int			rc = 0;
 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
 	u32			command;
+	int			i;
 
 	spin_lock_irq(&xhci->lock);
 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
@@ -604,6 +670,7 @@ int xhci_suspend(struct xhci_hcd *xhci)
 		spin_unlock_irq(&xhci->lock);
 		return -ETIMEDOUT;
 	}
+	xhci_clear_command_ring(xhci);
 
 	/* step 3: save registers */
 	xhci_save_registers(xhci);
@@ -617,10 +684,15 @@ int xhci_suspend(struct xhci_hcd *xhci)
 		spin_unlock_irq(&xhci->lock);
 		return -ETIMEDOUT;
 	}
-	/* step 5: remove core well power */
-	xhci_cleanup_msix(xhci);
 	spin_unlock_irq(&xhci->lock);
 
+	/* step 5: remove core well power */
+	/* synchronize irq when using MSI-X */
+	if (xhci->msix_entries) {
+		for (i = 0; i < xhci->msix_count; i++)
+			synchronize_irq(xhci->msix_entries[i].vector);
+	}
+
 	return rc;
 }
 
@@ -634,8 +706,6 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 {
 	u32			command, temp = 0;
 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
-	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
-	u64	val_64;
 	int	old_state, retval;
 
 	old_state = hcd->state;
@@ -648,15 +718,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		/* step 1: restore register */
 		xhci_restore_registers(xhci);
 		/* step 2: initialize command ring buffer */
-		val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
-		val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
-			 (xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
-					       xhci->cmd_ring->dequeue) &
-			 (u64) ~CMD_RING_RSVD_BITS) |
-			 xhci->cmd_ring->cycle_state;
-		xhci_dbg(xhci, "// Setting command ring address to 0x%llx\n",
-				(long unsigned long) val_64);
-		xhci_write_64(xhci, val_64, &xhci->op_regs->cmd_ring);
+		xhci_set_cmd_ring_deq(xhci);
 		/* step 3: restore state and start state*/
 		/* step 3: set CRS flag */
 		command = xhci_readl(xhci, &xhci->op_regs->command);
@@ -678,9 +740,8 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		xhci_dbg(xhci, "Stop HCD\n");
 		xhci_halt(xhci);
 		xhci_reset(xhci);
-		if (hibernated)
-			xhci_cleanup_msix(xhci);
 		spin_unlock_irq(&xhci->lock);
+		xhci_cleanup_msix(xhci);
 
 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
 		/* Tell the event ring poll function not to reschedule */
@@ -714,28 +775,6 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		return retval;
 	}
 
-	/* Re-setup MSI-X */
-	if (hcd->irq)
-		free_irq(hcd->irq, hcd);
-	hcd->irq = -1;
-
-	retval = xhci_setup_msix(xhci);
-	if (retval)
-		/* fall back to msi*/
-		retval = xhci_setup_msi(xhci);
-
-	if (retval) {
-		/* fall back to legacy interrupt*/
-		retval = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,
-					hcd->irq_descr, hcd);
-		if (retval) {
-			xhci_err(xhci, "request interrupt %d failed\n",
-					pdev->irq);
-			return retval;
-		}
-		hcd->irq = pdev->irq;
-	}
-
 	/* step 4: set Run/Stop bit */
 	command = xhci_readl(xhci, &xhci->op_regs->command);
 	command |= CMD_RUN;
@@ -1496,6 +1535,15 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
 		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 ((command->command_trb->link.control & TRB_TYPE_BITMASK)
+				== TRB_TYPE(TRB_LINK))
+			command->command_trb =
+				xhci->cmd_ring->enq_seg->next->trbs;
+
 		list_add_tail(&command->cmd_list, &virt_dev->cmd_list);
 	} else {
 		in_ctx = virt_dev->in_ctx;
@@ -2219,6 +2267,15 @@ int xhci_discover_or_reset_device(struct usb_hcd *hcd, struct usb_device *udev)
 	/* 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 ((reset_device_cmd->command_trb->link.control & TRB_TYPE_BITMASK)
+			== TRB_TYPE(TRB_LINK))
+		reset_device_cmd->command_trb =
+			xhci->cmd_ring->enq_seg->next->trbs;
+
 	list_add_tail(&reset_device_cmd->cmd_list, &virt_dev->cmd_list);
 	ret = xhci_queue_reset_device(xhci, slot_id);
 	if (ret) {
@@ -2374,8 +2431,12 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
 		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)) {
+	/* xhci_alloc_virt_device() does not touch rings; no need to lock.
+	 * Use GFP_NOIO, since this function can be called from
+	 * xhci_discover_or_reset_device(), which may be called as part of
+	 * mass storage driver error handling.
+	 */
+	if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_NOIO)) {
 		/* 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);