USB: xhci: Refactor code to free or cache endpoint rings.

[~andy/linux] / drivers / usb / host / xhci-mem.c

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index bffcef7a5545ec87dbdcc24cd0d43a45be401f60..1f1f8a0f2e66d3a8aa6f167384361f92f354b9a9 100644 (file)
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -198,6 +198,31 @@ fail:
        return 0;
 }
 
+void xhci_free_or_cache_endpoint_ring(struct xhci_hcd *xhci,
+               struct xhci_virt_device *virt_dev,
+               unsigned int ep_index)
+{
+       int rings_cached;
+
+       rings_cached = virt_dev->num_rings_cached;
+       if (rings_cached < XHCI_MAX_RINGS_CACHED) {
+               virt_dev->num_rings_cached++;
+               rings_cached = virt_dev->num_rings_cached;
+               virt_dev->ring_cache[rings_cached] =
+                       virt_dev->eps[ep_index].ring;
+               xhci_dbg(xhci, "Cached old ring, "
+                               "%d ring%s cached\n",
+                               rings_cached,
+                               (rings_cached > 1) ? "s" : "");
+       } else {
+               xhci_ring_free(xhci, virt_dev->eps[ep_index].ring);
+               xhci_dbg(xhci, "Ring cache full (%d rings), "
+                               "freeing ring\n",
+                               virt_dev->num_rings_cached);
+       }
+       virt_dev->eps[ep_index].ring = NULL;
+}
+
 /* Zero an endpoint ring (except for link TRBs) and move the enqueue and dequeue
  * pointers to the beginning of the ring.
  */