From 78c58a53c9864447f2a46d4c06dd3c2616823ad2 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 31 Aug 2011 17:12:02 +0200 Subject: [PATCH] usb: dwc3: gadget: do not map/unmap ZLP transfers If the gadget drivers sends a ZLP we are trying to map this this request which does not work on all implementations. So we simply skip mapping it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 0c934a195deb..1de4d3f87569 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -61,6 +61,11 @@ void dwc3_map_buffer_to_dma(struct dwc3_request *req) { struct dwc3 *dwc = req->dep->dwc; + if (req->request.length == 0) { + /* req->request.dma = dwc->setup_buf_addr; */ + return; + } + if (req->request.dma == DMA_ADDR_INVALID) { req->request.dma = dma_map_single(dwc->dev, req->request.buf, req->request.length, req->direction @@ -78,6 +83,11 @@ void dwc3_unmap_buffer_from_dma(struct dwc3_request *req) { struct dwc3 *dwc = req->dep->dwc; + if (req->request.length == 0) { + req->request.dma = DMA_ADDR_INVALID; + return; + } + if (req->mapped) { dma_unmap_single(dwc->dev, req->request.dma, req->request.length, req->direction -- 2.20.1