diff options
Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 33 |
1 files changed, 28 insertions, 5 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index f9b6fa3..4194f34 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2490,6 +2490,8 @@ static void queue_trb(struct xhci_hcd *xhci, struct xhci_ring *ring, static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring, u32 ep_state, unsigned int num_trbs, gfp_t mem_flags) { + unsigned int num_trbs_needed; + /* Make sure the endpoint has been added to xHC schedule */ switch (ep_state) { case EP_STATE_DISABLED: @@ -2517,11 +2519,32 @@ static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring, */ return -EINVAL; } - if (!room_on_ring(xhci, ep_ring, num_trbs)) { - /* FIXME allocate more room */ - xhci_err(xhci, "ERROR no room on ep ring\n"); - return -ENOMEM; - } + + while (1) { + if (room_on_ring(xhci, ep_ring, num_trbs)) + break; + + if (ep_ring == xhci->cmd_ring) { + xhci_err(xhci, "Do not support expand command ring\n"); + return -ENOMEM; + } + + if (ep_ring->enq_seg == ep_ring->deq_seg && + ep_ring->dequeue > ep_ring->enqueue) { + xhci_err(xhci, "Can not expand the ring while dequeue " + "pointer has not passed the link TRB\n"); + return -ENOMEM; + } + + xhci_dbg(xhci, "ERROR no room on ep ring, " + "try ring expansion\n"); + num_trbs_needed = num_trbs - ep_ring->num_trbs_free; + if (xhci_ring_expansion(xhci, ep_ring, num_trbs_needed, + mem_flags)) { + xhci_err(xhci, "Ring expansion failed\n"); + return -ENOMEM; + } + }; if (enqueue_is_link_trb(ep_ring)) { struct xhci_ring *ring = ep_ring; |
