From 21c3ee93867694e8c7382ff77b4645b50d3233e9 Mon Sep 17 00:00:00 2001 From: Igor Kotrasinski Date: Tue, 15 Sep 2015 16:55:29 +0200 Subject: [PATCH] usb: gadget: dummy_hcd: emulate sending zlp in packet logic currently, when a zlp flag is set and an urb/usb_request buffer is filled without a short packet, transfer() leaves its status at -EINPROGRESS and does not rescan for short packet. In a scenario where ep.maxpacket bytes are copied, URB_ZERO_PACKET is set, urb buffer is filled and usb_request buffer is not, transfer() returns with an urb with -EINPROGRESS status, which dummy_hcd treats as incomplete transfer. Check for zlp and rescan appropriately. Signed-off-by: Igor Kotrasinski Signed-off-by: Felipe Balbi --- drivers/usb/gadget/udc/dummy_hcd.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c index 1379ad40d864..93b38f88e7b2 100644 --- a/drivers/usb/gadget/udc/dummy_hcd.c +++ b/drivers/usb/gadget/udc/dummy_hcd.c @@ -1429,15 +1429,24 @@ top: req->req.status = 0; } - /* many requests terminate without a short packet */ + /* + * many requests terminate without a short packet. + * send a zlp if demanded by flags. + */ } else { - if (req->req.length == req->req.actual - && !req->req.zero) - req->req.status = 0; - if (urb->transfer_buffer_length == urb->actual_length - && !(urb->transfer_flags - & URB_ZERO_PACKET)) - *status = 0; + if (req->req.length == req->req.actual) { + if (req->req.zero && to_host) + rescan = 1; + else + req->req.status = 0; + } + if (urb->transfer_buffer_length == urb->actual_length) { + if (urb->transfer_flags & URB_ZERO_PACKET && + !to_host) + rescan = 1; + else + *status = 0; + } } /* device side completion --> continuable */ -- 2.20.1