usbip: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-throughSigned-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200707195214.GA3932@embeddedorSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/usbip/stub_rx.c

@@ -424,7 +424,7 @@ static void masking_bogus_flags(struct urb *urb)
 	case USB_ENDPOINT_XFER_BULK:
 		if (is_out)
 			allowed |= URB_ZERO_PACKET;
-		/* FALLTHROUGH */
+		fallthrough;
 	default:			/* all non-iso endpoints */
 		if (!is_out)
 			allowed |= URB_SHORT_NOT_OK;

drivers/usb/usbip/vhci_hcd.c

@@ -508,7 +508,7 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 		case USB_PORT_FEAT_U1_TIMEOUT:
 			usbip_dbg_vhci_rh(
 				" SetPortFeature: USB_PORT_FEAT_U1_TIMEOUT\n");
-			/* Fall through */
+			fallthrough;
 		case USB_PORT_FEAT_U2_TIMEOUT:
 			usbip_dbg_vhci_rh(
 				" SetPortFeature: USB_PORT_FEAT_U2_TIMEOUT\n");
@@ -561,7 +561,7 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 				       "supported for USB 2.0 roothub\n");
 				goto error;
 			}
-			/* FALLS THROUGH */
+			fallthrough;
 		case USB_PORT_FEAT_RESET:
 			usbip_dbg_vhci_rh(
 				" SetPortFeature: USB_PORT_FEAT_RESET\n");
@@ -584,8 +584,7 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 
 			/* 50msec reset signaling */
 			vhci_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
-
-			/* FALLS THROUGH */
+			fallthrough;
 		default:
 			usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 					  wValue);

drivers/usb/usbip/vhci_rx.c

@@ -27,7 +27,7 @@ struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum)
 
 		switch (status) {
 		case -ENOENT:
-			/* fall through */
+			fallthrough;
 		case -ECONNRESET:
 			dev_dbg(&urb->dev->dev,
 				 "urb seq# %u was unlinked %ssynchronously\n",

drivers/usb/usbip/vudc_transfer.c

@@ -404,7 +404,7 @@ static void v_timer(struct timer_list *t)
 			 * for now, give unlimited bandwidth
 			 */
 			limit += urb->transfer_buffer_length;
-			/* fallthrough */
+			fallthrough;
 		default:
 treat_control_like_bulk:
 			total -= transfer(udc, urb, ep, limit);
@@ -479,7 +479,7 @@ void v_kick_timer(struct vudc *udc, unsigned long time)
 		return;
 	case VUDC_TR_IDLE:
 		t->state = VUDC_TR_RUNNING;
-		/* fallthrough */
+		fallthrough;
 	case VUDC_TR_STOPPED:
 		/* we may want to kick timer to unqueue urbs */
 		mod_timer(&t->timer, time);