From 1c9e86c933eaf0bcd579f26453f76e1114a8d834 Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Thu, 24 Sep 2020 01:21:43 -0700 Subject: [PATCH] usb: dwc3: ep0: Fix ZLP for OUT ep0 requests commit 66706077dc89c66a4777a4c6298273816afb848c upstream. The current ZLP handling for ep0 requests is only for control IN requests. For OUT direction, DWC3 needs to check and setup for MPS alignment. Usually, control OUT requests can indicate its transfer size via the wLength field of the control message. So usb_request->zero is usually not needed for OUT direction. To handle ZLP OUT for control endpoint, make sure the TRB is MPS size. Cc: stable@vger.kernel.org Fixes: c7fcdeb2627c ("usb: dwc3: ep0: simplify EP0 state machine") Fixes: d6e5a549cc4d ("usb: dwc3: simplify ZLP handling") Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/ep0.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index 6dee4dabc0a43..697656aad6ea7 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -942,12 +942,16 @@ static void dwc3_ep0_xfer_complete(struct dwc3 *dwc, static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, struct dwc3_ep *dep, struct dwc3_request *req) { + unsigned int trb_length = 0; int ret; req->direction = !!dep->number; if (req->request.length == 0) { - dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0, + if (!req->direction) + trb_length = dep->endpoint.maxpacket; + + dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, trb_length, DWC3_TRBCTL_CONTROL_DATA, false); ret = dwc3_ep0_start_trans(dep); } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) @@ -994,9 +998,12 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1]; + if (!req->direction) + trb_length = dep->endpoint.maxpacket; + /* Now prepare one extra TRB to align transfer size */ dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, - 0, DWC3_TRBCTL_CONTROL_DATA, + trb_length, DWC3_TRBCTL_CONTROL_DATA, false); ret = dwc3_ep0_start_trans(dep); } else {