Merge tag 'driver-core-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git...

[cascardo/linux.git] / drivers / usb / dwc3 / gadget.c

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 07cc892..1dfa56a 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -783,6 +783,7 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
                req->trb = trb;
                req->trb_dma = dwc3_trb_dma_offset(dep, trb);
                req->first_trb_index = dep->trb_enqueue;
+               dep->queued_requests++;
        }
 
        dwc3_ep_inc_enq(dep);
@@ -833,8 +834,6 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 
        trb->ctrl |= DWC3_TRB_CTRL_HWO;
 
-       dep->queued_requests++;
-
        trace_dwc3_prepare_trb(dep, trb);
 }
 
@@ -1074,9 +1073,17 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
 
        list_add_tail(&req->list, &dep->pending_list);
 
-       if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
-                       dep->flags & DWC3_EP_PENDING_REQUEST) {
-               if (list_empty(&dep->started_list)) {
+       /*
+        * NOTICE: Isochronous endpoints should NEVER be prestarted. We must
+        * wait for a XferNotReady event so we will know what's the current
+        * (micro-)frame number.
+        *
+        * Without this trick, we are very, very likely gonna get Bus Expiry
+        * errors which will force us issue EndTransfer command.
+        */
+       if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
+               if ((dep->flags & DWC3_EP_PENDING_REQUEST) &&
+                               list_empty(&dep->started_list)) {
                        dwc3_stop_active_transfer(dwc, dep->number, true);
                        dep->flags = DWC3_EP_ENABLED;
                }
@@ -1861,8 +1868,11 @@ static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
        unsigned int            s_pkt = 0;
        unsigned int            trb_status;
 
-       dep->queued_requests--;
        dwc3_ep_inc_deq(dep);
+
+       if (req->trb == trb)
+               dep->queued_requests--;
+
        trace_dwc3_complete_trb(dep, trb);
 
        /*
@@ -2980,7 +2990,7 @@ err3:
        kfree(dwc->setup_buf);
 
 err2:
-       dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
+       dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
                        dwc->ep0_trb, dwc->ep0_trb_addr);
 
 err1:
@@ -3005,7 +3015,7 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
        kfree(dwc->setup_buf);
        kfree(dwc->zlp_buf);
 
-       dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
+       dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
                        dwc->ep0_trb, dwc->ep0_trb_addr);
 
        dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),