Messages in this thread | | | Subject | Re: [PATCH v2 1/1] usb: xhci: fix checking ep busy for CFC | From | Sergei Shtylyov <> | Date | Thu, 29 Oct 2015 15:51:42 +0300 |
| |
Hello.
On 10/29/2015 5:46 AM, Lu Baolu wrote:
> Function ep_ring_is_processing() checks the dequeue pointer > in endpoint context to know whether an endpoint is busy with > processing TRBs. This is not correct since dequeue pointer > field in an endpoint context is only valid when the endpoint > is in Halted or Stopped states. This buggy code causes audio > noise when playing sound with USB headset connected to host > controllers which support CFC (one of xhci 1.1 features). > > This patch should exist in stable kernel since v4.3. > > Reported-and-tested-by: YD Tseng <yd_tseng@asmedia.com.tw> > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > > --- > v1->v2: > Implement the logic in xhci_queue_isoc_tx_prepare() instead of > a seperated function as suggested by Mathias. > > --- > drivers/usb/host/xhci-ring.c | 32 ++++++-------------------------- > 1 file changed, 6 insertions(+), 26 deletions(-) > > diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c > index fa83625..8edc286 100644 > --- a/drivers/usb/host/xhci-ring.c > +++ b/drivers/usb/host/xhci-ring.c [...] > @@ -3983,10 +3961,12 @@ int xhci_queue_isoc_tx_prepare(struct xhci_hcd *xhci, gfp_t mem_flags, > } > > /* Calculate the start frame and put it in urb->start_frame. */ > - if (HCC_CFC(xhci->hcc_params) && > - ep_ring_is_processing(xhci, slot_id, ep_index)) { > - urb->start_frame = xep->next_frame_id; > - goto skip_start_over; > + if (HCC_CFC(xhci->hcc_params)) { > + if ((le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK) > + == EP_STATE_RUNNING && > + !list_empty(&ep_ring->td_list)) > + urb->start_frame = xep->next_frame_id; > + goto skip_start_over;
Forgot {}?
> } > > start_frame = readl(&xhci->run_regs->microframe_index);
MBR, Sergei
| |