From: Andiry Xu <andiry.xu@xxxxxxx> giveback_first_trb() controls the cycle bit set of the start_trb, to ensure that the start_trb is written last and the host controller will receive a whole td at a time. However, if the ring is wrapped and cycle bit is toggled to zero, then giveback_first_trb() will be of no effect. In this case, set the cycle bit of start_trb to 1 at the beginning and clear it in giveback_first_trb(). Signed-off-by: Andiry Xu <andiry.xu@xxxxxxx> Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> --- drivers/usb/host/xhci-ring.c | 28 +++++++++++++++++++++------- 1 files changed, 21 insertions(+), 7 deletions(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 59f81b5..1ee6de9 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2421,7 +2421,10 @@ static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id, * isn't reordered. */ wmb(); - start_trb->field[3] |= start_cycle; + if (start_cycle) + start_trb->field[3] |= start_cycle; + else + start_trb->field[3] &= ~0x1; xhci_ring_ep_doorbell(xhci, slot_id, ep_index, stream_id); } @@ -2551,9 +2554,11 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, u32 remainder = 0; /* Don't change the cycle bit of the first TRB until later */ - if (first_trb) + if (first_trb) { first_trb = false; - else + if (start_cycle == 0) + field |= 0x1; + } else field |= ep_ring->cycle_state; /* Chain all the TRBs together; clear the chain bit in the last @@ -2711,9 +2716,11 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, field = 0; /* Don't change the cycle bit of the first TRB until later */ - if (first_trb) + if (first_trb) { first_trb = false; - else + if (start_cycle == 0) + field |= 0x1; + } else field |= ep_ring->cycle_state; /* Chain all the TRBs together; clear the chain bit in the last @@ -2818,13 +2825,17 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, /* Queue setup TRB - see section 6.4.1.2.1 */ /* FIXME better way to translate setup_packet into two u32 fields? */ setup = (struct usb_ctrlrequest *) urb->setup_packet; + field = 0; + field |= TRB_IDT | TRB_TYPE(TRB_SETUP); + if (start_cycle == 0) + field |= 0x1; queue_trb(xhci, ep_ring, false, true, /* FIXME endianness is probably going to bite my ass here. */ setup->bRequestType | setup->bRequest << 8 | setup->wValue << 16, setup->wIndex | setup->wLength << 16, TRB_LEN(8) | TRB_INTR_TARGET(0), /* Immediate data in pointer */ - TRB_IDT | TRB_TYPE(TRB_SETUP)); + field); /* If there's data, queue data TRBs */ field = 0; @@ -2951,7 +2962,10 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags, field |= TRB_TYPE(TRB_ISOC); /* Assume URB_ISO_ASAP is set */ field |= TRB_SIA; - if (i > 0) + if (i == 0) { + if (start_cycle == 0) + field |= 0x1; + } else field |= ep_ring->cycle_state; first_trb = false; } else { -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html