USB: xhci: Refactor test for vendor-specific completion codes.

All commands that can be issued to the xHCI hardware can come back with
vendor-specific "informational" completion codes.  These are to be treated
like a successful completion code.  Refactor out the code to test for the
range of these codes and print debugging messages.

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

drivers/usb/host/xhci-ring.c

@@ -1080,6 +1080,20 @@ static int xhci_requires_manual_halt_cleanup(struct xhci_hcd *xhci,
 	return 0;
 }
 
+int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code)
+{
+	if (trb_comp_code >= 224 && trb_comp_code <= 255) {
+		/* Vendor defined "informational" completion code,
+		 * treat as not-an-error.
+		 */
+		xhci_dbg(xhci, "Vendor defined info completion code %u\n",
+				trb_comp_code);
+		xhci_dbg(xhci, "Treating code as success.\n");
+		return 1;
+	}
+	return 0;
+}
+
 /*
  * If this function returns an error condition, it means it got a Transfer
  * event with a corrupted Slot ID, Endpoint ID, or TRB DMA address.
@@ -1196,13 +1210,7 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 		status = -ENOSR;
 		break;
 	default:
-		if (trb_comp_code >= 224 && trb_comp_code <= 255) {
-			/* Vendor defined "informational" completion code,
-			 * treat as not-an-error.
-			 */
-			xhci_dbg(xhci, "Vendor defined info completion code %u\n",
-					trb_comp_code);
-			xhci_dbg(xhci, "Treating code as success.\n");
+		if (xhci_is_vendor_info_code(xhci, trb_comp_code)) {
 			status = 0;
 			break;
 		}

drivers/usb/host/xhci.h

@@ -1276,6 +1276,7 @@ dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg, union xhci_trb *trb);
 struct xhci_segment *trb_in_td(struct xhci_segment *start_seg,
 		union xhci_trb *start_trb, union xhci_trb *end_trb,
 		dma_addr_t suspect_dma);
+int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code);
 void xhci_ring_cmd_db(struct xhci_hcd *xhci);
 void *xhci_setup_one_noop(struct xhci_hcd *xhci);
 void xhci_handle_event(struct xhci_hcd *xhci);