Commit 0416e494 authored Aug 10, 2012 by Pratyush Anand Committed by Felipe Balbi Sep 06, 2012

usb: dwc3: ep0: correct cache sync issue in case of ep0_bounced

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->ep0_bounce to request->buf, so we do not need to
issue cache sync function. In fact, 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.

Cc: <stable@vger.kernel.org> # v3.4 v3.5
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

parent ea0e6276

drivers/usb/dwc3/ep0.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -720,7 +720,6 @@ 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;
		}

drivers/usb/dwc3/gadget.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -263,6 +263,9 @@ void dwc3_gadget_giveback(struct dwc3_ep dep, struct dwc3_request req,
		if (req->request.status == -EINPROGRESS)
		req->request.status = status;

		if (dwc->ep0_bounced && dep->number == 0)
		dwc->ep0_bounced = false;
		else
		usb_gadget_unmap_request(&dwc->gadget, &req->request,
		req->direction);

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