diff options
Diffstat (limited to 'drivers/usb/host/xhci-hcd.c')
| -rw-r--r-- | drivers/usb/host/xhci-hcd.c | 32 |
1 files changed, 27 insertions, 5 deletions
diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c index 0d5a8564ed1..5e92c72df64 100644 --- a/drivers/usb/host/xhci-hcd.c +++ b/drivers/usb/host/xhci-hcd.c @@ -1262,13 +1262,35 @@ int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev) LAST_CTX_TO_EP_NUM(slot_ctx->dev_info)); xhci_zero_in_ctx(xhci, virt_dev); - /* Free any old rings */ + /* Install new rings and free or cache any old rings */ for (i = 1; i < 31; ++i) { - 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; + int rings_cached; + + if (!virt_dev->eps[i].new_ring) + continue; + /* Only cache or free the old ring if it exists. + * It may not if this is the first add of an endpoint. + */ + if (virt_dev->eps[i].ring) { + 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[i].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[i].ring); + xhci_dbg(xhci, "Ring cache full (%d rings), " + "freeing ring\n", + virt_dev->num_rings_cached); + } } + virt_dev->eps[i].ring = virt_dev->eps[i].new_ring; + virt_dev->eps[i].new_ring = NULL; } return ret; |