diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 54 |
1 files changed, 2 insertions, 52 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 55fc0c3..6bfbd80 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2929,58 +2929,8 @@ static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring, } while (1) { - if (room_on_ring(xhci, ep_ring, num_trbs)) { - union xhci_trb *trb = ep_ring->enqueue; - unsigned int usable = ep_ring->enq_seg->trbs + - TRBS_PER_SEGMENT - 1 - trb; - u32 nop_cmd; - - /* - * Section 4.11.7.1 TD Fragments states that a link - * TRB must only occur at the boundary between - * data bursts (eg 512 bytes for 480M). - * While it is possible to split a large fragment - * we don't know the size yet. - * Simplest solution is to fill the trb before the - * LINK with nop commands. - */ - if (num_trbs == 1 || num_trbs <= usable || usable == 0) - break; - - if (ep_ring->type != TYPE_BULK) - /* - * While isoc transfers might have a buffer that - * crosses a 64k boundary it is unlikely. - * Since we can't add NOPs without generating - * gaps in the traffic just hope it never - * happens at the end of the ring. - * This could be fixed by writing a LINK TRB - * instead of the first NOP - however the - * TRB_TYPE_LINK_LE32() calls would all need - * changing to check the ring length. - */ - break; - - if (num_trbs >= TRBS_PER_SEGMENT) { - xhci_err(xhci, "Too many fragments %d, max %d\n", - num_trbs, TRBS_PER_SEGMENT - 1); - return -ENOMEM; - } - - nop_cmd = cpu_to_le32(TRB_TYPE(TRB_TR_NOOP) | - ep_ring->cycle_state); - ep_ring->num_trbs_free -= usable; - do { - trb->generic.field[0] = 0; - trb->generic.field[1] = 0; - trb->generic.field[2] = 0; - trb->generic.field[3] = nop_cmd; - trb++; - } while (--usable); - ep_ring->enqueue = trb; - if (room_on_ring(xhci, ep_ring, num_trbs)) - break; - } + 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"); |