From 760f9dc129d41a76934d149ccc762590006a6f6a Mon Sep 17 00:00:00 2001 From: Reyad Attiyat Date: Thu, 6 Aug 2015 19:23:58 +0300 Subject: [PATCH] usb: xhci: Add support for URB_ZERO_PACKET to bulk/sg transfers 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 Signed-off-by: Mathias Nyman Cc: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- 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 fe223cfaab0b..4ba6974dd4b6 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -3167,9 +3167,11 @@ 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; @@ -3185,13 +3187,27 @@ 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]; /* @@ -3221,6 +3237,7 @@ 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; @@ -3238,12 +3255,15 @@ 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 */ @@ -3305,7 +3325,7 @@ 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, @@ -3323,7 +3343,9 @@ 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; @@ -3354,7 +3376,6 @@ 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, @@ -3363,6 +3384,20 @@ 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]; /* @@ -3384,7 +3419,7 @@ 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; @@ -3401,12 +3436,15 @@ 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 */ @@ -3444,7 +3482,7 @@ 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 1a22d186bef7..a3431e90345f 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1300,6 +1300,11 @@ 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; -- 2.20.1