On Tue, Jul 20, 2010 at 04:49:32PM +0800, Andiry Xu wrote:
> >From d5408b33be2e6b0d617214229aeb8f5142273af6 Mon Sep 17 00:00:00 2001
> From: Andiry Xu <andiry.xu@xxxxxxx>
> Date: Mon, 19 Jul 2010 15:24:36 +0800
> Subject: [PATCH 09/10] 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>
Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
> ---
> 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 4e51e36..a728c19 100644
> --- a/drivers/usb/host/xhci-mem.c
> +++ b/drivers/usb/host/xhci-mem.c
> @@ -1111,8 +1111,18 @@ 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
> + * carries 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)
> --
> 1.7.0.4
>
>
>
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