From 36f05d36b03523da906cf2ae70ec31af6f57e94c Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Sun, 29 Mar 2020 16:13:10 -0700 Subject: [PATCH] usb: dwc3: gadget: Issue END_TRANSFER to retry isoc transfer After a number of unsuccessful start isoc attempts due to bus-expiry status, issue END_TRANSFER command and retry on the next XferNotReady event. Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index a6aebe5..dc03c04 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1413,7 +1413,8 @@ static int __dwc3_gadget_start_isoc(struct dwc3_ep *dep) int ret; int i; - if (list_empty(&dep->pending_list)) { + if (list_empty(&dep->pending_list) && + list_empty(&dep->started_list)) { dep->flags |= DWC3_EP_PENDING_REQUEST; return -EAGAIN; } @@ -1436,6 +1437,27 @@ static int __dwc3_gadget_start_isoc(struct dwc3_ep *dep) break; } + /* + * After a number of unsuccessful start attempts due to bus-expiry + * status, issue END_TRANSFER command and retry on the next XferNotReady + * event. + */ + if (ret == -EAGAIN) { + struct dwc3_gadget_ep_cmd_params params; + u32 cmd; + + cmd = DWC3_DEPCMD_ENDTRANSFER | + DWC3_DEPCMD_CMDIOC | + DWC3_DEPCMD_PARAM(dep->resource_index); + + dep->resource_index = 0; + memset(¶ms, 0, sizeof(params)); + + ret = dwc3_send_gadget_ep_cmd(dep, cmd, ¶ms); + if (!ret) + dep->flags |= DWC3_EP_END_TRANSFER_PENDING; + } + return ret; } @@ -2663,6 +2685,18 @@ static void dwc3_gadget_endpoint_transfer_not_ready(struct dwc3_ep *dep, const struct dwc3_event_depevt *event) { dwc3_gadget_endpoint_frame_from_event(dep, event); + + /* + * The XferNotReady event is generated only once before the endpoint + * starts. It will be generated again when END_TRANSFER command is + * issued. For some controller versions, the XferNotReady event may be + * generated while the END_TRANSFER command is still in process. Ignore + * it and wait for the next XferNotReady event after the command is + * completed. + */ + if (dep->flags & DWC3_EP_END_TRANSFER_PENDING) + return; + (void) __dwc3_gadget_start_isoc(dep); } -- 2.7.4