[PATCH AUTOSEL 4.19 072/172] usb: dwc3: gadget: Properly handle failed kick_transfer

From: Sasha Levin
Date: Wed Jun 17 2020 - 22:02:23 EST


From: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>

[ Upstream commit 8d99087c2db863c5fa3a4a1f3cb82b3a493705ca ]

If dwc3 fails to issue START_TRANSFER/UPDATE_TRANSFER command, then we
should properly end an active transfer and give back all the started
requests. However if it's for an isoc endpoint, the failure maybe due to
bus-expiry status. In this case, don't give back the requests and wait
for the next retry.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/usb/dwc3/gadget.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 8e66954dfcd4..2f5f4ca5c0d0 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1217,6 +1217,8 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep)
}
}

+static void dwc3_gadget_ep_cleanup_cancelled_requests(struct dwc3_ep *dep);
+
static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
{
struct dwc3_gadget_ep_cmd_params params;
@@ -1253,14 +1255,20 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)

ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
if (ret < 0) {
- /*
- * FIXME we need to iterate over the list of requests
- * here and stop, unmap, free and del each of the linked
- * requests instead of what we do now.
- */
- if (req->trb)
- memset(req->trb, 0, sizeof(struct dwc3_trb));
- dwc3_gadget_del_and_unmap_request(dep, req, ret);
+ struct dwc3_request *tmp;
+
+ if (ret == -EAGAIN)
+ return ret;
+
+ dwc3_stop_active_transfer(dep, true, true);
+
+ list_for_each_entry_safe(req, tmp, &dep->started_list, list)
+ dwc3_gadget_move_cancelled_request(req);
+
+ /* If ep isn't started, then there's no end transfer pending */
+ if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+ dwc3_gadget_ep_cleanup_cancelled_requests(dep);
+
return ret;
}

--
2.25.1