Sorry I have forgotten to change the dp loop check line in the bulk_sg function. Will resubmit. On Sun, Jun 28, 2015 at 7:36 PM, Reyad Attiyat <reyad.attiyat@xxxxxxxxx> wrote: > 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 > max packet length. > > Signed-off-by: Reyad Attiyat <reyad.attiyat@xxxxxxxxx> > --- > drivers/usb/host/xhci-ring.c | 41 ++++++++++++++++++++++++++++++++--------- > 1 file changed, 32 insertions(+), 9 deletions(-) > > diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c > index 7d34cbf..fb24099 100644 > --- a/drivers/usb/host/xhci-ring.c > +++ b/drivers/usb/host/xhci-ring.c > @@ -3040,7 +3040,9 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, > int num_sgs; > int trb_buff_len, this_sg_len, running_total; > unsigned int total_packet_count; > + bool zero_length_needed; > bool first_trb; > + int last_trb; > u64 addr; > bool more_trbs_coming; > > @@ -3056,6 +3058,14 @@ 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)); > > + /* Deal with URB_ZERO_PACKET - need one more td/trb */ > + zero_length_needed = (urb->transfer_flags & URB_ZERO_PACKET) > + && !(urb->transfer_buffer_length % usb_endpoint_maxp(&urb->ep->desc)); > + if(zero_length_needed){ > + num_trbs++; > + xhci_dbg(xhci, "Creating zero length td.\n"); > + } > + > trb_buff_len = prepare_transfer(xhci, xhci->devs[slot_id], > ep_index, urb->stream_id, > num_trbs, urb, 0, mem_flags); > @@ -3092,6 +3102,7 @@ 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 = zero_length_needed ? 2 : 1; > /* Queue the first TRB, even if it's zero-length */ > do { > u32 field = 0; > @@ -3109,12 +3120,13 @@ 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) { > field |= TRB_CHAIN; > - } else { > - /* FIXME - add check for ZERO_PACKET flag before this */ > + } else if (num_trbs == last_trb) { > td->last_trb = ep_ring->enqueue; > field |= TRB_IOC; > + } else if (zero_length_needed && num_trbs == 1) { > + trb_buff_len = 0; > } > > /* Only set interrupt on short packet for IN endpoints */ > @@ -3194,7 +3206,9 @@ 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; > bool more_trbs_coming; > + bool zero_length_needed; > int start_cycle; > u32 field, length_field; > > @@ -3225,7 +3239,14 @@ 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 */ > + > + /* Deal with URB_ZERO_PACKET - need one more td/trb */ > + zero_length_needed = (urb->transfer_flags & URB_ZERO_PACKET) > + && !(urb->transfer_buffer_length % usb_endpoint_maxp(&urb->ep->desc)); > + 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, > @@ -3255,7 +3276,7 @@ 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 = zero_length_needed ? 2 : 1; > /* Queue the first TRB, even if it's zero-length */ > do { > u32 remainder = 0; > @@ -3272,12 +3293,14 @@ 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) { > field |= TRB_CHAIN; > - } else { > - /* FIXME - add check for ZERO_PACKET flag before this */ > + } else if (num_trbs == last_trb) { > td->last_trb = ep_ring->enqueue; > field |= TRB_IOC; > + } else if (zero_length_needed && num_trbs == 1) { > + trb_buff_len = 0; > } > > /* Only set interrupt on short packet for IN endpoints */ > @@ -3315,7 +3338,7 @@ 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, > -- > 2.4.3 > -- 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