3 files changed, 35 insertions, 5 deletions

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 6615f641b34f..5d642660fd15 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -218,7 +218,7 @@ out:
 	return ret;
 }
 
-static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
+void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
 {
 	struct dwc3_ep		*dep;
 
@@ -1088,13 +1088,18 @@ void dwc3_ep0_send_delayed_status(struct dwc3 *dwc)
 	__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
 }
 
-static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
+void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
 {
 	struct dwc3_gadget_ep_cmd_params params;
 	u32			cmd;
 	int			ret;
 
-	if (!dep->resource_index)
+	/*
+	 * For status/DATA OUT stage, TRB will be queued on ep0 out
+	 * endpoint for which resource index is zero. Hence allow
+	 * queuing ENDXFER command for ep0 out endpoint.
+	 */
+	if (!dep->resource_index && dep->number)
 		return;
 
 	cmd = DWC3_DEPCMD_ENDTRANSFER;
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 4f54f0ef21df..8c366fa82105 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -882,12 +882,13 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep, unsigned int action)
 		reg |= DWC3_DALEPENA_EP(dep->number);
 		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 
+		dep->trb_dequeue = 0;
+		dep->trb_enqueue = 0;
+
 		if (usb_endpoint_xfer_control(desc))
 			goto out;
 
 		/* Initialize the TRB ring */
-		dep->trb_dequeue = 0;
-		dep->trb_enqueue = 0;
 		memset(dep->trb_pool, 0,
 		       sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
 
@@ -2741,6 +2742,7 @@ static int __dwc3_gadget_start(struct dwc3 *dwc)
 
 	/* begin to receive SETUP packets */
 	dwc->ep0state = EP0_SETUP_PHASE;
+	dwc->ep0_bounced = false;
 	dwc->link_state = DWC3_LINK_STATE_SS_DIS;
 	dwc->delayed_status = false;
 	dwc3_ep0_out_start(dwc);
@@ -3820,6 +3822,27 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
 	}
 
 	dwc3_reset_gadget(dwc);
+
+	/*
+	 * From SNPS databook section 8.1.2, the EP0 should be in setup
+	 * phase. So ensure that EP0 is in setup phase by issuing a stall
+	 * and restart if EP0 is not in setup phase.
+	 */
+	if (dwc->ep0state != EP0_SETUP_PHASE) {
+		unsigned int	dir;
+
+		dir = !!dwc->ep0_expect_in;
+		if (dwc->ep0state == EP0_DATA_PHASE)
+			dwc3_ep0_end_control_data(dwc, dwc->eps[dir]);
+		else
+			dwc3_ep0_end_control_data(dwc, dwc->eps[!dir]);
+
+		dwc->eps[0]->trb_enqueue = 0;
+		dwc->eps[1]->trb_enqueue = 0;
+
+		dwc3_ep0_stall_and_restart(dwc);
+	}
+
 	/*
 	 * In the Synopsis DesignWare Cores USB3 Databook Rev. 3.30a
 	 * Section 4.1.2 Table 4-2, it states that during a USB reset, the SW
diff --git a/drivers/usb/dwc3/gadget.h b/drivers/usb/dwc3/gadget.h
index f763380e672e..55a56cf67d73 100644
--- a/drivers/usb/dwc3/gadget.h
+++ b/drivers/usb/dwc3/gadget.h
@@ -110,6 +110,8 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 void dwc3_ep0_interrupt(struct dwc3 *dwc,
 		const struct dwc3_event_depevt *event);
 void dwc3_ep0_out_start(struct dwc3 *dwc);
+void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep);
+void dwc3_ep0_stall_and_restart(struct dwc3 *dwc);
 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value);
 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value);
 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,