xhci: refactor TRB_CONFIG_EP case into function

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_CONFIG_EP switch case, in
handle_cmd_completion(), into a fuction named xhci_handle_cmd_config_ep().

There were added two additional variables, 'add_flags' and 'drop_flags',
to reduce line length below 80 chars and improve code readability.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

drivers/usb/host/xhci-ring.c

@@ -1407,6 +1407,66 @@ static void xhci_handle_cmd_disable_slot(struct xhci_hcd *xhci, int slot_id)
 	xhci_free_virt_device(xhci, slot_id);
 }
 
+static void xhci_handle_cmd_config_ep(struct xhci_hcd *xhci, int slot_id,
+		struct xhci_event_cmd *event, u32 cmd_comp_code)
+{
+	struct xhci_virt_device *virt_dev;
+	struct xhci_input_control_ctx *ctrl_ctx;
+	unsigned int ep_index;
+	unsigned int ep_state;
+	u32 add_flags, drop_flags;
+
+	virt_dev = xhci->devs[slot_id];
+	if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
+		return;
+	/*
+	 * Configure endpoint commands can come from the USB core
+	 * configuration or alt setting changes, or because the HW
+	 * needed an extra configure endpoint command after a reset
+	 * endpoint command or streams were being configured.
+	 * If the command was for a halted endpoint, the xHCI driver
+	 * is not waiting on the configure endpoint command.
+	 */
+	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
+	if (!ctrl_ctx) {
+		xhci_warn(xhci, "Could not get input context, bad type.\n");
+		return;
+	}
+
+	add_flags = le32_to_cpu(ctrl_ctx->add_flags);
+	drop_flags = le32_to_cpu(ctrl_ctx->drop_flags);
+	/* Input ctx add_flags are the endpoint index plus one */
+	ep_index = xhci_last_valid_endpoint(add_flags) - 1;
+
+	/* A usb_set_interface() call directly after clearing a halted
+	 * condition may race on this quirky hardware.  Not worth
+	 * worrying about, since this is prototype hardware.  Not sure
+	 * if this will work for streams, but streams support was
+	 * untested on this prototype.
+	 */
+	if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
+			ep_index != (unsigned int) -1 &&
+			add_flags - SLOT_FLAG == drop_flags) {
+		ep_state = virt_dev->eps[ep_index].ep_state;
+		if (!(ep_state & EP_HALTED))
+			goto bandwidth_change;
+		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
+				"Completed config ep cmd - "
+				"last ep index = %d, state = %d",
+				ep_index, ep_state);
+		/* Clear internal halted state and restart ring(s) */
+		virt_dev->eps[ep_index].ep_state &= ~EP_HALTED;
+		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
+		return;
+	}
+bandwidth_change:
+	xhci_dbg_trace(xhci,  trace_xhci_dbg_context_change,
+			"Completed config ep cmd");
+	virt_dev->cmd_status = cmd_comp_code;
+	complete(&virt_dev->cmd_completion);
+	return;
+}
+
 static void xhci_handle_cmd_eval_ctx(struct xhci_hcd *xhci, int slot_id,
 		struct xhci_event_cmd *event, u32 cmd_comp_code)
 {
@@ -1459,10 +1519,6 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
 	int slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags));
 	u64 cmd_dma;
 	dma_addr_t cmd_dequeue_dma;
-	struct xhci_input_control_ctx *ctrl_ctx;
-	struct xhci_virt_device *virt_dev;
-	unsigned int ep_index;
-	unsigned int ep_state;
 
 	cmd_dma = le64_to_cpu(event->cmd_trb);
 	cmd_dequeue_dma = xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
@@ -1512,54 +1568,8 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
 		xhci_handle_cmd_disable_slot(xhci, slot_id);
 		break;
 	case TRB_TYPE(TRB_CONFIG_EP):
-		virt_dev = xhci->devs[slot_id];
-		if (handle_cmd_in_cmd_wait_list(xhci, virt_dev, event))
-			break;
-		/*
-		 * Configure endpoint commands can come from the USB core
-		 * configuration or alt setting changes, or because the HW
-		 * needed an extra configure endpoint command after a reset
-		 * endpoint command or streams were being configured.
-		 * If the command was for a halted endpoint, the xHCI driver
-		 * is not waiting on the configure endpoint command.
-		 */
-		ctrl_ctx = xhci_get_input_control_ctx(xhci,
-				virt_dev->in_ctx);
-		if (!ctrl_ctx) {
-			xhci_warn(xhci, "Could not get input context, bad type.\n");
-			break;
-		}
-		/* Input ctx add_flags are the endpoint index plus one */
-		ep_index = xhci_last_valid_endpoint(le32_to_cpu(ctrl_ctx->add_flags)) - 1;
-		/* A usb_set_interface() call directly after clearing a halted
-		 * condition may race on this quirky hardware.  Not worth
-		 * worrying about, since this is prototype hardware.  Not sure
-		 * if this will work for streams, but streams support was
-		 * untested on this prototype.
-		 */
-		if (xhci->quirks & XHCI_RESET_EP_QUIRK &&
-				ep_index != (unsigned int) -1 &&
-		    le32_to_cpu(ctrl_ctx->add_flags) - SLOT_FLAG ==
-		    le32_to_cpu(ctrl_ctx->drop_flags)) {
-			ep_state = xhci->devs[slot_id]->eps[ep_index].ep_state;
-			if (!(ep_state & EP_HALTED))
-				goto bandwidth_change;
-			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
-					"Completed config ep cmd - "
-					"last ep index = %d, state = %d",
-					ep_index, ep_state);
-			/* Clear internal halted state and restart ring(s) */
-			xhci->devs[slot_id]->eps[ep_index].ep_state &=
-				~EP_HALTED;
-			ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
-			break;
-		}
-bandwidth_change:
-		xhci_dbg_trace(xhci,  trace_xhci_dbg_context_change,
-				"Completed config ep cmd");
-		xhci->devs[slot_id]->cmd_status =
-			GET_COMP_CODE(le32_to_cpu(event->status));
-		complete(&xhci->devs[slot_id]->cmd_completion);
+		xhci_handle_cmd_config_ep(xhci, slot_id, event,
+				GET_COMP_CODE(le32_to_cpu(event->status)));
 		break;
 	case TRB_TYPE(TRB_EVAL_CONTEXT):
 		xhci_handle_cmd_eval_ctx(xhci, slot_id, event,