>From b514c9b2149448d8dc8de42572184d359d27e718 Mon Sep 17 00:00:00 2001
From: Andiry Xu <andiry.xu@xxxxxxx>
Date: Tue, 20 Apr 2010 17:18:24 +0800
Subject: [PATCH] xHCI: allocate bigger ring for isochronous endpoint
Isochronous endpoint needs a bigger size of transfer ring. Isochronous URB
consists of multiple packets, each packet needs a isoc td to carry, and
there will be multiple trbs inserted to the ring at one time. One segment
is too small for isochronous endpoints, and it will result in
room_on_ring() check failure and the URB is failed to enqueue.
Allocate bigger ring for isochronous endpoint. 8 segments should be enough.
This will be replaced with dynamic ring expansion in the future.
Signed-off-by: Andiry Xu <andiry.xu@xxxxxxx>
---
drivers/usb/host/xhci-mem.c | 14 ++++++++++++--
1 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index c09539b..ee51252 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -628,8 +628,18 @@ 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->eps[ep_index].new_ring =
- xhci_ring_alloc(xhci, 1, true, mem_flags);
+ /*
+ * Isochronous endpoint ring needs bigger size because one isoc URB
+ * carriess multiple packets and it will insert multiple tds to the
+ * ring.
+ * This should be replaced with dynamic ring resizing in the future.
+ */
+ if (usb_endpoint_xfer_isoc(&ep->desc))
+ virt_dev->eps[ep_index].new_ring =
+ xhci_ring_alloc(xhci, 8, true, mem_flags);
+ else
+ virt_dev->eps[ep_index].new_ring =
+ xhci_ring_alloc(xhci, 1, true, mem_flags);
if (!virt_dev->eps[ep_index].new_ring) {
/* Attempt to use the ring cache */
if (virt_dev->num_rings_cached == 0)
--
1.6.3.3
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