usb: dwc2: drd: fix sleeping while spinlock atomic context

If GINTSTS.CURMODE is not yet reflecting the expecting mode after calling dwc2_force_mode, we enter in the dwc2_wait_for_mode function while under spinlock atomic context. To avoid this situation, move the call to dwc2_force_mode after the spinlock atomic context. Change-Id: If30c9bf19249be8c5d07e229f4067e6d013092cb Fixes: 5ec811a6ab7b ("usb: dwc2: add DRD support with role switch and override Vbus/ID signals") Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/linux-stm32/+/173585 Reviewed-by: CITOOLS <smet-aci-reviews@lists.codex.cro.st.com> Reviewed-by: Fabrice GASNIER <fabrice.gasnier@st.com>
STMicroelectronics · mcarlin-ds · Jul 13, 2020 · Jul 21, 2020 · Jul 21, 2020 · Jul 24, 2020
commit bbb6e11690f1aa9b6a0512274b52417d4fb8d5ca
diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c
@@ -70,6 +70,7 @@ static int dwc2_drd_role_sw_set(struct device *dev, enum usb_role role)
 {
 	struct dwc2_hsotg *hsotg = dev_get_drvdata(dev);
 	unsigned long flags;
+	int already = 0;
 
 	/* Skip session not in line with dr_mode */
 	if ((role == USB_ROLE_DEVICE && hsotg->dr_mode == USB_DR_MODE_HOST) ||
@@ -88,41 +89,27 @@ static int dwc2_drd_role_sw_set(struct device *dev, enum usb_role role)
 	spin_lock_irqsave(&hsotg->lock, flags);
 
 	if (role == USB_ROLE_HOST) {
-		if (dwc2_ovr_avalid(hsotg, true))
-			goto unlock;
-
-		if (hsotg->dr_mode == USB_DR_MODE_OTG)
-			/*
-			 * This will raise a Connector ID Status Change
-			 * Interrupt - connID A
-			 */
-			dwc2_force_mode(hsotg, true);
+		already = dwc2_ovr_avalid(hsotg, true);
 	} else if (role == USB_ROLE_DEVICE) {
-		if (dwc2_ovr_bvalid(hsotg, true))
-			goto unlock;
-
-		if (hsotg->dr_mode == USB_DR_MODE_OTG)
-			/*
-			 * This will raise a Connector ID Status Change
-			 * Interrupt - connID B
-			 */
-			dwc2_force_mode(hsotg, false);
-
+		already = dwc2_ovr_bvalid(hsotg, true);
 		/* This clear DCTL.SFTDISCON bit */
 		dwc2_hsotg_core_connect(hsotg);
 	} else {
 		if (dwc2_is_device_mode(hsotg)) {
-		    if (!dwc2_ovr_bvalid(hsotg, false))
-			/* This set DCTL.SFTDISCON bit */
-			dwc2_hsotg_core_disconnect(hsotg);
+			if (!dwc2_ovr_bvalid(hsotg, false))
+				/* This set DCTL.SFTDISCON bit */
+				dwc2_hsotg_core_disconnect(hsotg);
 		} else {
 			dwc2_ovr_avalid(hsotg, false);
 		}
 	}
 
-unlock:
 	spin_unlock_irqrestore(&hsotg->lock, flags);
 
+	if (!already && hsotg->dr_mode == USB_DR_MODE_OTG)
+		/* This will raise a Connector ID Status Change Interrupt */
+		dwc2_force_mode(hsotg, role == USB_ROLE_HOST);
+
 	dev_dbg(hsotg->dev, "%s-session valid\n",
 		role == USB_ROLE_NONE ? "No" :
 		role == USB_ROLE_HOST ? "A" : "B");