[PATCH] usb/dwc3: Correct cache sync issue in case of ep0 bounced

[Pratyush Anand <pratyush.anand@xxxxxx>]

In case of ep0 out, if length is not aligned to maxpacket size then we
use dwc->ep_bounce_addr for dma transfer and not request->dma. Since, we
have alreday done memcpy from dwc->ep_bounce to request->buf, so we do
not need to issue cache sync function. Infact, cache sync function will
bring wrong data in request->buf from request->dma in this scenario.

So, cache sync function must not be executed in case of ep0 bounced.

Signed-off-by: Pratyush Anand <pratyush.anand@xxxxxx>
---
 drivers/usb/dwc3/ep0.c    |    1 -
 drivers/usb/dwc3/gadget.c |    7 +++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 7b99c5a..1e88de8 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -804,7 +804,6 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 		transferred = min_t(u32, ur->length,
 				transfer_size - length);
 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
-		dwc->ep0_bounced = false;
 	} else {
 		transferred = ur->length - length;
 	}
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 800944f..4205a6c 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -263,8 +263,11 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 	if (req->request.status == -EINPROGRESS)
 		req->request.status = status;
 
-	usb_gadget_unmap_request(&dwc->gadget, &req->request,
-			req->direction);
+	if (!dwc->ep0_bounced)
+		usb_gadget_unmap_request(&dwc->gadget, &req->request,
+				req->direction);
+	else
+		dwc->ep0_bounced = false;
 
 	dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n",
 			req, dep->name, req->request.actual,
-- 
1.7.5.4

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