From e1cf486d881d853d710e2d86a7adfc5fd260990f Mon Sep 17 00:00:00 2001 From: Alex He Date: Fri, 3 Jun 2011 15:58:25 +0800 Subject: xHCI 1.0: Force Stopped Event(FSE) FSE shall occur on the TD natural boundary. The software ep_ring dequeue pointer exceed the hardware ep_ring dequeue pointer in these cases of Table-3. As a result, the event_trb(pointed by hardware dequeue pointer) of the FSE can't be found in the current TD(pointed by software dequeue pointer). What should we do is to figured out the FSE case and skip over it. Signed-off-by: Alex He Signed-off-by: Sarah Sharp --- drivers/usb/host/xhci-ring.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'drivers/usb/host/xhci-ring.c') diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 800f417c7309..0c008497edfd 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2063,6 +2063,20 @@ static int handle_tx_event(struct xhci_hcd *xhci, /* Is this a TRB in the currently executing TD? */ event_seg = trb_in_td(ep_ring->deq_seg, ep_ring->dequeue, td->last_trb, event_dma); + + /* + * Skip the Force Stopped Event. The event_trb(event_dma) of FSE + * is not in the current TD pointed by ep_ring->dequeue because + * that the hardware dequeue pointer still at the previous TRB + * of the current TD. The previous TRB maybe a Link TD or the + * last TRB of the previous TD. The command completion handle + * will take care the rest. + */ + if (!event_seg && trb_comp_code == COMP_STOP_INVAL) { + ret = 0; + goto cleanup; + } + if (!event_seg) { if (!ep->skip || !usb_endpoint_xfer_isoc(&td->urb->ep->desc)) { -- cgit From f6ba6fe2d913da6707a71a413d6ec8ae98d6ce18 Mon Sep 17 00:00:00 2001 From: Alex He Date: Wed, 8 Jun 2011 18:34:06 +0800 Subject: xHCI 1.0: Incompatible Device Error It is one new TRB Completion Code for the xHCI spec v1.0. Asserted if the xHC detects a problem with a device that does not allow it to be successfully accessed, e.g. due to a device compliance or compatibility problem. This error may be returned by any command or transfer, and is fatal as far as the Slot is concerned. Return -EPROTO by urb->status or frame->status of ISOC for transfer case. And return -ENODEV for configure endpoint command, evaluate context command and address device command if there is an incompatible Device Error. The error codes will be sent back to the USB core to decide how to do. It's unnecessary for other commands because after the three commands run successfully means that the device has been accepted. Signed-off-by: Alex He Signed-off-by: Sarah Sharp --- drivers/usb/host/xhci-ring.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/usb/host/xhci-ring.c') diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 0c008497edfd..436332aa341b 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1733,6 +1733,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td, frame->status = -EOVERFLOW; skip_td = true; break; + case COMP_DEV_ERR: case COMP_STALL: frame->status = -EPROTO; skip_td = true; @@ -2016,6 +2017,10 @@ static int handle_tx_event(struct xhci_hcd *xhci, TRB_TO_SLOT_ID(le32_to_cpu(event->flags)), ep_index); goto cleanup; + case COMP_DEV_ERR: + xhci_warn(xhci, "WARN: detect an incompatible device"); + status = -EPROTO; + break; case COMP_MISSED_INT: /* * When encounter missed service error, one or more isoc tds -- cgit From b3df3f9c7df9a8d85e03e158d35487618a160901 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 15 Jun 2011 19:57:46 -0700 Subject: xhci: Always set urb->status to zero for isoc endpoints. When the xHCI driver encounters a Missed Service Interval event for an isochronous endpoint ring, it means the host controller skipped over one or more isochronous TDs. For TD that is skipped, skip_isoc_td() is called. This sets the frame descriptor status to -EXDEV, and also sets the value stored in the int pointed to by status to -EXDEV. If the isochronous TD happens to be the last TD in an URB, handle_tx_event() will use the status variable to give back the URB to the USB core. That means drivers will see urb->status as -EXDEV. It turns out that EHCI, UHCI, and OHCI always set urb->status to zero for an isochronous urb, regardless of what the frame status is. See itd_complete() in ehci-sched.c: } else { /* URB was too late */ desc->status = -EXDEV; } } /* handle completion now? */ if (likely ((urb_index + 1) != urb->number_of_packets)) goto done; /* ASSERT: it's really the last itd for this urb list_for_each_entry (itd, &stream->td_list, itd_list) BUG_ON (itd->urb == urb); */ /* give urb back to the driver; completion often (re)submits */ dev = urb->dev; ehci_urb_done(ehci, urb, 0); ehci_urb_done() completes the URB with the status of the third argument, which is always zero in this case. It turns out that many USB webcam drivers, such as uvcvideo, cannot handle urb->status set to a non-zero value. They will not resubmit their isochronous URBs in that case, and userspace will see a frozen video. Change the xHCI driver to be consistent with the EHCI and UHCI driver, and always set urb->status to 0 for isochronous URBs. This patch should be backported to kernels as old as 2.6.36 Signed-off-by: Sarah Sharp Cc: "Xu, Andiry" Cc: stable@kernel.org --- drivers/usb/host/xhci-ring.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'drivers/usb/host/xhci-ring.c') diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 436332aa341b..70cacbbe7fb9 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1768,9 +1768,6 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td, } } - if ((idx == urb_priv->length - 1) && *status == -EINPROGRESS) - *status = 0; - return finish_td(xhci, td, event_trb, event, ep, status, false); } @@ -1788,8 +1785,7 @@ static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td, idx = urb_priv->td_cnt; frame = &td->urb->iso_frame_desc[idx]; - /* The transfer is partly done */ - *status = -EXDEV; + /* The transfer is partly done. */ frame->status = -EXDEV; /* calc actual length */ @@ -2177,6 +2173,11 @@ cleanup: urb->transfer_buffer_length, status); spin_unlock(&xhci->lock); + /* EHCI, UHCI, and OHCI always unconditionally set the + * urb->status of an isochronous endpoint to 0. + */ + if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) + status = 0; usb_hcd_giveback_urb(bus_to_hcd(urb->dev->bus), urb, status); spin_lock(&xhci->lock); } -- cgit