USB: xhci: Endpoint representation refactoring.

The xhci_ring structure contained information that is really related to an
endpoint, not a ring.  This will cause problems later when endpoint
streams are supported and there are multiple rings per endpoint.

Move the endpoint state and cancellation information into a new virtual
endpoint structure, xhci_virt_ep.  The list of TRBs to be cancelled should
be per endpoint, not per ring, for easy access.  There can be only one TRB
that the endpoint stopped on after a stop endpoint command (even with
streams enabled); move the stopped TRB information into the new virtual
endpoint structure.  Also move the 31 endpoint rings and temporary ring
storage from the virtual device structure (xhci_virt_device) into the
virtual endpoint structure (xhci_virt_ep).
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/xhci-hcd.c

@@ -351,13 +351,14 @@ void xhci_event_ring_work(unsigned long arg)
 	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]) {
+		if (!xhci->devs[i])
+			continue;
 		for (j = 0; j < 31; ++j) {
-				if (xhci->devs[i]->ep_rings[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, xhci->devs[i]->ep_rings[j]->deq_seg);
-				}
-			}
+			xhci_debug_segment(xhci, ring->deq_seg);
 		}
 	}
 
@@ -778,6 +779,7 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 	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);
@@ -790,17 +792,18 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 	xhci_dbg(xhci, "Event ring:\n");
 	xhci_debug_ring(xhci, xhci->event_ring);
 	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
-	ep_ring = xhci->devs[urb->dev->slot_id]->ep_rings[ep_index];
+	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;
 
-	ep_ring->cancels_pending++;
-	list_add_tail(&td->cancelled_td_list, &ep_ring->cancelled_td_list);
+	ep->cancels_pending++;
+	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_ring->cancels_pending == 1) {
+	if (ep->cancels_pending == 1) {
 		xhci_queue_stop_endpoint(xhci, urb->dev->slot_id, ep_index);
 		xhci_ring_cmd_db(xhci);
 	}
@@ -1206,10 +1209,10 @@ int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
 	xhci_zero_in_ctx(xhci, virt_dev);
 	/* Free any old rings */
 	for (i = 1; i < 31; ++i) {
-		if (virt_dev->new_ep_rings[i]) {
-			xhci_ring_free(xhci, virt_dev->ep_rings[i]);
-			virt_dev->ep_rings[i] = virt_dev->new_ep_rings[i];
-			virt_dev->new_ep_rings[i] = NULL;
+		if (virt_dev->eps[i].new_ring) {
+			xhci_ring_free(xhci, virt_dev->eps[i].ring);
+			virt_dev->eps[i].ring = virt_dev->eps[i].new_ring;
+			virt_dev->eps[i].new_ring = NULL;
 		}
 	}
 
@@ -1236,9 +1239,9 @@ void xhci_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
 	virt_dev = xhci->devs[udev->slot_id];
 	/* Free any rings allocated for added endpoints */
 	for (i = 0; i < 31; ++i) {
-		if (virt_dev->new_ep_rings[i]) {
-			xhci_ring_free(xhci, virt_dev->new_ep_rings[i]);
-			virt_dev->new_ep_rings[i] = NULL;
+		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);
@@ -1281,17 +1284,18 @@ void xhci_setup_input_ctx_for_quirk(struct xhci_hcd *xhci,
 }
 
 void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
-		struct usb_device *udev,
-		unsigned int ep_index, struct xhci_ring *ep_ring)
+		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_ring->stopped_td,
+			ep_index, ep->stopped_td,
 			&deq_state);
 
 	/* HW with the reset endpoint quirk will use the saved dequeue state to
@@ -1299,8 +1303,7 @@ void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
 	 */
 	if (!(xhci->quirks & XHCI_RESET_EP_QUIRK)) {
 		xhci_dbg(xhci, "Queueing new dequeue state\n");
-		xhci_queue_new_dequeue_state(xhci, ep_ring,
-				udev->slot_id,
+		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
@@ -1327,7 +1330,7 @@ void xhci_endpoint_reset(struct usb_hcd *hcd,
 	unsigned int ep_index;
 	unsigned long flags;
 	int ret;
-	struct xhci_ring *ep_ring;
+	struct xhci_virt_ep *virt_ep;
 
 	xhci = hcd_to_xhci(hcd);
 	udev = (struct usb_device *) ep->hcpriv;
@@ -1337,8 +1340,8 @@ void xhci_endpoint_reset(struct usb_hcd *hcd,
 	if (!ep->hcpriv)
 		return;
 	ep_index = xhci_get_endpoint_index(&ep->desc);
-	ep_ring = xhci->devs[udev->slot_id]->ep_rings[ep_index];
-	if (!ep_ring->stopped_td) {
+	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;
@@ -1357,8 +1360,8 @@ void xhci_endpoint_reset(struct usb_hcd *hcd,
 	 * command.  Better hope that last command worked!
 	 */
 	if (!ret) {
-		xhci_cleanup_stalled_ring(xhci, udev, ep_index, ep_ring);
-		kfree(ep_ring->stopped_td);
+		xhci_cleanup_stalled_ring(xhci, udev, ep_index);
+		kfree(virt_ep->stopped_td);
 		xhci_ring_cmd_db(xhci);
 	}
 	spin_unlock_irqrestore(&xhci->lock, flags);

drivers/usb/host/xhci-mem.c

@@ -144,7 +144,6 @@ static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
 		return 0;
 
 	INIT_LIST_HEAD(&ring->td_list);
-	INIT_LIST_HEAD(&ring->cancelled_td_list);
 	if (num_segs == 0)
 		return ring;
 
@@ -265,8 +264,8 @@ void xhci_free_virt_device(struct xhci_hcd *xhci, int slot_id)
 		return;
 
 	for (i = 0; i < 31; ++i)
-		if (dev->ep_rings[i])
-			xhci_ring_free(xhci, dev->ep_rings[i]);
+		if (dev->eps[i].ring)
+			xhci_ring_free(xhci, dev->eps[i].ring);
 
 	if (dev->in_ctx)
 		xhci_free_container_ctx(xhci, dev->in_ctx);
@@ -281,6 +280,7 @@ int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id,
 		struct usb_device *udev, gfp_t flags)
 {
 	struct xhci_virt_device *dev;
+	int i;
 
 	/* Slot ID 0 is reserved */
 	if (slot_id == 0 || xhci->devs[slot_id]) {
@@ -309,9 +309,13 @@ int xhci_alloc_virt_device(struct xhci_hcd *xhci, int slot_id,
 	xhci_dbg(xhci, "Slot %d input ctx = 0x%llx (dma)\n", slot_id,
 			(unsigned long long)dev->in_ctx->dma);
 
+	/* Initialize the cancellation list for each endpoint */
+	for (i = 0; i < 31; i++)
+		INIT_LIST_HEAD(&dev->eps[i].cancelled_td_list);
+
 	/* Allocate endpoint 0 ring */
-	dev->ep_rings[0] = xhci_ring_alloc(xhci, 1, true, flags);
-	if (!dev->ep_rings[0])
+	dev->eps[0].ring = xhci_ring_alloc(xhci, 1, true, flags);
+	if (!dev->eps[0].ring)
 		goto fail;
 
 	init_completion(&dev->cmd_completion);
@@ -428,8 +432,8 @@ int xhci_setup_addressable_virt_dev(struct xhci_hcd *xhci, struct usb_device *ud
 	ep0_ctx->ep_info2 |= ERROR_COUNT(3);
 
 	ep0_ctx->deq =
-		dev->ep_rings[0]->first_seg->dma;
-	ep0_ctx->deq |= dev->ep_rings[0]->cycle_state;
+		dev->eps[0].ring->first_seg->dma;
+	ep0_ctx->deq |= dev->eps[0].ring->cycle_state;
 
 	/* Steps 7 and 8 were done in xhci_alloc_virt_device() */
 
@@ -539,10 +543,11 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
 	ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
 
 	/* Set up the endpoint ring */
-	virt_dev->new_ep_rings[ep_index] = xhci_ring_alloc(xhci, 1, true, mem_flags);
-	if (!virt_dev->new_ep_rings[ep_index])
+	virt_dev->eps[ep_index].new_ring =
+		xhci_ring_alloc(xhci, 1, true, mem_flags);
+	if (!virt_dev->eps[ep_index].new_ring)
 		return -ENOMEM;
-	ep_ring = virt_dev->new_ep_rings[ep_index];
+	ep_ring = virt_dev->eps[ep_index].new_ring;
 	ep_ctx->deq = ep_ring->first_seg->dma | ep_ring->cycle_state;
 
 	ep_ctx->ep_info = xhci_get_endpoint_interval(udev, ep);

drivers/usb/host/xhci.h

@@ -625,6 +625,23 @@ struct xhci_input_control_ctx {
 /* add context bitmasks */
 #define	ADD_EP(x)	(0x1 << x)
 
+struct xhci_virt_ep {
+	struct xhci_ring		*ring;
+	/* Temporary storage in case the configure endpoint command fails and we
+	 * have to restore the device state to the previous state
+	 */
+	struct xhci_ring		*new_ring;
+	unsigned int			ep_state;
+#define SET_DEQ_PENDING		(1 << 0)
+#define EP_HALTED		(1 << 1)
+	/* ----  Related to URB cancellation ---- */
+	struct list_head	cancelled_td_list;
+	unsigned int		cancels_pending;
+	/* The TRB that was last reported in a stopped endpoint ring */
+	union xhci_trb		*stopped_trb;
+	struct xhci_td		*stopped_td;
+};
+
 struct xhci_virt_device {
 	/*
 	 * Commands to the hardware are passed an "input context" that
@@ -637,13 +654,7 @@ struct xhci_virt_device {
 	struct xhci_container_ctx       *out_ctx;
 	/* Used for addressing devices and configuration changes */
 	struct xhci_container_ctx       *in_ctx;
-
-	/* FIXME when stream support is added */
-	struct xhci_ring		*ep_rings[31];
-	/* Temporary storage in case the configure endpoint command fails and we
-	 * have to restore the device state to the previous state
-	 */
-	struct xhci_ring		*new_ep_rings[31];
+	struct xhci_virt_ep		eps[31];
 	struct completion		cmd_completion;
 	/* Status of the last command issued for this device */
 	u32				cmd_status;
@@ -945,15 +956,6 @@ struct xhci_ring {
 	struct xhci_segment	*deq_seg;
 	unsigned int		deq_updates;
 	struct list_head	td_list;
-	/* ----  Related to URB cancellation ---- */
-	struct list_head	cancelled_td_list;
-	unsigned int		cancels_pending;
-	unsigned int		state;
-#define SET_DEQ_PENDING		(1 << 0)
-#define EP_HALTED		(1 << 1)
-	/* The TRB that was last reported in a stopped endpoint ring */
-	union xhci_trb		*stopped_trb;
-	struct xhci_td		*stopped_td;
 	/*
 	 * Write the cycle state into the TRB cycle field to give ownership of
 	 * the TRB to the host controller (if we are the producer), or to check
@@ -1236,11 +1238,10 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
 		unsigned int slot_id, unsigned int ep_index,
 		struct xhci_td *cur_td, struct xhci_dequeue_state *state);
 void xhci_queue_new_dequeue_state(struct xhci_hcd *xhci,
-		struct xhci_ring *ep_ring, unsigned int slot_id,
-		unsigned int ep_index, struct xhci_dequeue_state *deq_state);
+		unsigned int slot_id, unsigned int ep_index,
+		struct xhci_dequeue_state *deq_state);
 void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
-		struct usb_device *udev,
-		unsigned int ep_index, struct xhci_ring *ep_ring);
+		struct usb_device *udev, unsigned int ep_index);
 void xhci_queue_config_ep_quirk(struct xhci_hcd *xhci,
 		unsigned int slot_id, unsigned int ep_index,
 		struct xhci_dequeue_state *deq_state);