From: Reyad Attiyat <reyad.attiyat@xxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 4758dcd19a7d9ba9610b38fecb93f65f56f86346 upstream. This commit checks for the URB_ZERO_PACKET flag and creates an extra zero-length td if the urb transfer length is a multiple of the endpoint's max packet length. Signed-off-by: Reyad Attiyat <reyad.attiyat@xxxxxxxxx> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Cc: Oliver Neukum <oneukum@xxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- drivers/usb/host/xhci-ring.c | 66 ++++++++++++++++++++++++++++++++++---------- drivers/usb/host/xhci.c | 5 ++++ 2 files changed, 57 insertions(+), 14 deletions(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 46da2f63d07b..ad381c22e5ac 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -3193,9 +3193,11 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct xhci_td *td; struct scatterlist *sg; int num_sgs; - int trb_buff_len, this_sg_len, running_total; + int trb_buff_len, this_sg_len, running_total, ret; unsigned int total_packet_count; + bool zero_length_needed; bool first_trb; + int last_trb_num; u64 addr; bool more_trbs_coming; @@ -3211,13 +3213,27 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, total_packet_count = DIV_ROUND_UP(urb->transfer_buffer_length, usb_endpoint_maxp(&urb->ep->desc)); - trb_buff_len = prepare_transfer(xhci, xhci->devs[slot_id], + ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index, urb->stream_id, num_trbs, urb, 0, mem_flags); - if (trb_buff_len < 0) - return trb_buff_len; + if (ret < 0) + return ret; urb_priv = urb->hcpriv; + + /* Deal with URB_ZERO_PACKET - need one more td/trb */ + zero_length_needed = urb->transfer_flags & URB_ZERO_PACKET && + urb_priv->length == 2; + if (zero_length_needed) { + num_trbs++; + xhci_dbg(xhci, "Creating zero length td.\n"); + ret = prepare_transfer(xhci, xhci->devs[slot_id], + ep_index, urb->stream_id, + 1, urb, 1, mem_flags); + if (ret < 0) + return ret; + } + td = urb_priv->td[0]; /* @@ -3247,6 +3263,7 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, trb_buff_len = urb->transfer_buffer_length; first_trb = true; + last_trb_num = zero_length_needed ? 2 : 1; /* Queue the first TRB, even if it's zero-length */ do { u32 field = 0; @@ -3264,12 +3281,15 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, /* Chain all the TRBs together; clear the chain bit in the last * TRB to indicate it's the last TRB in the chain. */ - if (num_trbs > 1) { + if (num_trbs > last_trb_num) { field |= TRB_CHAIN; - } else { - /* FIXME - add check for ZERO_PACKET flag before this */ + } else if (num_trbs == last_trb_num) { td->last_trb = ep_ring->enqueue; field |= TRB_IOC; + } else if (zero_length_needed && num_trbs == 1) { + trb_buff_len = 0; + urb_priv->td[1]->last_trb = ep_ring->enqueue; + field |= TRB_IOC; } /* Only set interrupt on short packet for IN endpoints */ @@ -3331,7 +3351,7 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, if (running_total + trb_buff_len > urb->transfer_buffer_length) trb_buff_len = urb->transfer_buffer_length - running_total; - } while (running_total < urb->transfer_buffer_length); + } while (num_trbs > 0); check_trb_math(urb, num_trbs, running_total); giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id, @@ -3349,7 +3369,9 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, int num_trbs; struct xhci_generic_trb *start_trb; bool first_trb; + int last_trb_num; bool more_trbs_coming; + bool zero_length_needed; int start_cycle; u32 field, length_field; @@ -3380,7 +3402,6 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, num_trbs++; running_total += TRB_MAX_BUFF_SIZE; } - /* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */ ret = prepare_transfer(xhci, xhci->devs[slot_id], ep_index, urb->stream_id, @@ -3389,6 +3410,20 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, return ret; urb_priv = urb->hcpriv; + + /* Deal with URB_ZERO_PACKET - need one more td/trb */ + zero_length_needed = urb->transfer_flags & URB_ZERO_PACKET && + urb_priv->length == 2; + if (zero_length_needed) { + num_trbs++; + xhci_dbg(xhci, "Creating zero length td.\n"); + ret = prepare_transfer(xhci, xhci->devs[slot_id], + ep_index, urb->stream_id, + 1, urb, 1, mem_flags); + if (ret < 0) + return ret; + } + td = urb_priv->td[0]; /* @@ -3410,7 +3445,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, trb_buff_len = urb->transfer_buffer_length; first_trb = true; - + last_trb_num = zero_length_needed ? 2 : 1; /* Queue the first TRB, even if it's zero-length */ do { u32 remainder = 0; @@ -3427,12 +3462,15 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, /* Chain all the TRBs together; clear the chain bit in the last * TRB to indicate it's the last TRB in the chain. */ - if (num_trbs > 1) { + if (num_trbs > last_trb_num) { field |= TRB_CHAIN; - } else { - /* FIXME - add check for ZERO_PACKET flag before this */ + } else if (num_trbs == last_trb_num) { td->last_trb = ep_ring->enqueue; field |= TRB_IOC; + } else if (zero_length_needed && num_trbs == 1) { + trb_buff_len = 0; + urb_priv->td[1]->last_trb = ep_ring->enqueue; + field |= TRB_IOC; } /* Only set interrupt on short packet for IN endpoints */ @@ -3470,7 +3508,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, trb_buff_len = urb->transfer_buffer_length - running_total; if (trb_buff_len > TRB_MAX_BUFF_SIZE) trb_buff_len = TRB_MAX_BUFF_SIZE; - } while (running_total < urb->transfer_buffer_length); + } while (num_trbs > 0); check_trb_math(urb, num_trbs, running_total); giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id, diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 319515406b4f..3d98a3a82c79 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1319,6 +1319,11 @@ int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags) if (usb_endpoint_xfer_isoc(&urb->ep->desc)) size = urb->number_of_packets; + else if (usb_endpoint_is_bulk_out(&urb->ep->desc) && + urb->transfer_buffer_length > 0 && + urb->transfer_flags & URB_ZERO_PACKET && + !(urb->transfer_buffer_length % usb_endpoint_maxp(&urb->ep->desc))) + size = 2; else size = 1; -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html