From a6829706ce0bae7e4623ea987a639d91a721eee2 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Sat, 27 Aug 2011 22:18:09 +0300 Subject: [PATCH] usb: dwc3: ep0: add handling for unaligned OUT transfers In case we have transfers which aren't aligned to wMaxPacketSize, we need to be careful with how we start the transfer with the HW. OUT transfers _must_ be aligned with wMaxPacketSize and in order to guarantee that, we use a bounce buffer. Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/ep0.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index a6fc5c316743..f1e0a5eb0544 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -185,10 +185,29 @@ static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep, req->epnum = dep->number; list_add_tail(&req->list, &dep->request_list); - dwc3_map_buffer_to_dma(req); + if (req->request.length == 0) { + ret = dwc3_ep0_start_trans(dwc, dep->number, + dwc->ctrl_req_addr, 0); + } else if ((req->request.length % dep->endpoint.maxpacket) + && (dep->number == 0)) { + dwc->ep0_bounced = true; + + WARN_ON(req->request.length > dep->endpoint.maxpacket); + + /* + * REVISIT in case request length is bigger than EP0 + * wMaxPacketSize, we will need two chained TRBs to handle + * the transfer. + */ + ret = dwc3_ep0_start_trans(dwc, dep->number, + dwc->ep0_bounce_addr, dep->endpoint.maxpacket); + } else { + dwc3_map_buffer_to_dma(req); + + ret = dwc3_ep0_start_trans(dwc, dep->number, + req->request.dma, req->request.length); + } - ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma, - req->request.length); if (ret < 0) { list_del(&req->list); dwc3_unmap_buffer_from_dma(req); @@ -655,8 +674,16 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc, dwc3_trb_to_nat(dwc->ep0_trb, &trb); - transferred = ur->length - trb.length; - ur->actual += transferred; + if (dwc->ep0_bounced) { + struct dwc3_ep *ep0 = dwc->eps[0]; + + transferred = min(ur->length, dep->endpoint.maxpacket - trb.length); + memcpy(ur->buf, dwc->ep0_bounce, transferred); + dwc->ep0_bounced = false; + } else { + transferred = ur->length - trb.length; + ur->actual += transferred; + } if ((epnum & 1) && ur->actual < ur->length) { /* for some reason we did not get everything out */ -- 2.20.1