Hi,
On Fri, Aug 10, 2012 at 01:36:42PM +0530, Pratyush Anand wrote:
> On 8/10/2012 1:07 PM, Felipe Balbi wrote:
> >Hi,
> >
> >On Fri, Aug 10, 2012 at 12:54:52PM +0530, Pratyush Anand wrote:
> >>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>
> >
> >this is very nice fix, but ...
> >
> >>---
> >> 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;
> >
> >I'm not sure this will work always, though. What if we have unaligned
> >ep0 out PLUS some started transfers on non-ep0/1 and those complete
> >before the unaligned ep0out transfer ?
>
> Yes , I think you are correct. In such scenario it might fail.
>
> >
> >You will be preventing cache sync on the non-ep0out transfer. I think
> >you need to check for ep0, something like:
> >
> >if ((dep->number == 0 && !dwc->ep0_bounced) ||
> > dep->number > 0)
> > usb_gadget_unmap_request();
> >else
> > dwc->ep0_bounced = false;
> >
> >or something similar.
> >
>
> if (dep->number == 0 && dwc->ep0_bounced)
> dwc->ep0_bounced = false;
> else
> usb_gadget_unmap_request();
>
> would be fine.
indeed. much simpler even :-)
--
balbi
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