usb: gadget: 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>
Link: https://lore.kernel.org/r/20200707171500.GA13620@embeddedorSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/composite.c

@@ -72,17 +72,17 @@ function_descriptors(struct usb_function *f,
 		descriptors = f->ssp_descriptors;
 		if (descriptors)
 			break;
-		/* FALLTHROUGH */
+		fallthrough;
 	case USB_SPEED_SUPER:
 		descriptors = f->ss_descriptors;
 		if (descriptors)
 			break;
-		/* FALLTHROUGH */
+		fallthrough;
 	case USB_SPEED_HIGH:
 		descriptors = f->hs_descriptors;
 		if (descriptors)
 			break;
-		/* FALLTHROUGH */
+		fallthrough;
 	default:
 		descriptors = f->fs_descriptors;
 	}
@@ -170,20 +170,20 @@ int config_ep_by_speed_and_alt(struct usb_gadget *g,
 			want_comp_desc = 1;
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	case USB_SPEED_SUPER:
 		if (gadget_is_superspeed(g)) {
 			speed_desc = f->ss_descriptors;
 			want_comp_desc = 1;
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	case USB_SPEED_HIGH:
 		if (gadget_is_dualspeed(g)) {
 			speed_desc = f->hs_descriptors;
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	default:
 		speed_desc = f->fs_descriptors;
 	}
@@ -237,7 +237,7 @@ int config_ep_by_speed_and_alt(struct usb_gadget *g,
 		case USB_ENDPOINT_XFER_ISOC:
 			/* mult: bits 1:0 of bmAttributes */
 			_ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
-			/* fall through */
+			fallthrough;
 		case USB_ENDPOINT_XFER_BULK:
 		case USB_ENDPOINT_XFER_INT:
 			_ep->maxburst = comp_desc->bMaxBurst + 1;
@@ -1697,7 +1697,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 			if (!gadget_is_dualspeed(gadget) ||
 			    gadget->speed >= USB_SPEED_SUPER)
 				break;
-			/* FALLTHROUGH */
+			fallthrough;
 		case USB_DT_CONFIG:
 			value = config_desc(cdev, w_value);
 			if (value >= 0)

drivers/usb/gadget/function/f_fs.c

@@ -2726,7 +2726,7 @@ static void __ffs_event_add(struct ffs_data *ffs,
 	switch (type) {
 	case FUNCTIONFS_RESUME:
 		rem_type2 = FUNCTIONFS_SUSPEND;
-		/* FALL THROUGH */
+		fallthrough;
 	case FUNCTIONFS_SUSPEND:
 	case FUNCTIONFS_SETUP:
 		rem_type1 = type;

drivers/usb/gadget/function/f_hid.c

@@ -477,7 +477,7 @@ static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)
 		break;
 	default:
 		ERROR(cdev, "Set report failed %d\n", req->status);
-		/* FALLTHROUGH */
+		fallthrough;
 	case -ECONNABORTED:		/* hardware forced ep reset */
 	case -ECONNRESET:		/* request dequeued */
 	case -ESHUTDOWN:		/* disconnect from host */

drivers/usb/gadget/function/f_mass_storage.c

@@ -2039,7 +2039,7 @@ static int do_scsi_command(struct fsg_common *common)
 	case RELEASE:
 	case RESERVE:
 	case SEND_DIAGNOSTIC:
-		/* Fall through */
+		fallthrough;
 
 	default:
 unknown_cmnd:

drivers/usb/gadget/function/f_phonet.c

@@ -212,7 +212,7 @@ static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
 	case -ESHUTDOWN: /* disconnected */
 	case -ECONNRESET: /* disabled */
 		dev->stats.tx_aborted_errors++;
-		/* fall through */
+		fallthrough;
 	default:
 		dev->stats.tx_errors++;
 	}
@@ -360,7 +360,7 @@ static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
 	/* Do resubmit in these cases: */
 	case -EOVERFLOW: /* request buffer overflow */
 		dev->stats.rx_over_errors++;
-		/* fall through */
+		fallthrough;
 	default:
 		dev->stats.rx_errors++;
 		break;

drivers/usb/gadget/function/f_printer.c

@@ -285,7 +285,7 @@ static void rx_complete(struct usb_ep *ep, struct usb_request *req)
 
 	/* data overrun */
 	case -EOVERFLOW:
-		/* FALLTHROUGH */
+		fallthrough;
 
 	default:
 		DBG(dev, "rx status %d\n", status);
@@ -304,7 +304,7 @@ static void tx_complete(struct usb_ep *ep, struct usb_request *req)
 	switch (req->status) {
 	default:
 		VDBG(dev, "tx err %d\n", req->status);
-		/* FALLTHROUGH */
+		fallthrough;
 	case -ECONNRESET:		/* unlink */
 	case -ESHUTDOWN:		/* disconnect etc */
 		break;
@@ -919,7 +919,7 @@ static bool gprinter_req_match(struct usb_function *f,
 		if (!w_value && !w_length &&
 		   !(USB_DIR_IN & ctrl->bRequestType))
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return false;
 	}

drivers/usb/gadget/function/f_rndis.c

@@ -426,7 +426,7 @@ static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
 		DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
 			ep->name, status,
 			req->actual, req->length);
-		/* FALLTHROUGH */
+		fallthrough;
 	case 0:
 		if (ep != rndis->notify)
 			break;

drivers/usb/gadget/function/f_tcm.c

@@ -1150,7 +1150,7 @@ static int usbg_submit_command(struct f_uas *fu,
 	default:
 		pr_debug_once("Unsupported prio_attr: %02x.\n",
 				cmd_iu->prio_attr);
-		/* fall through */
+		fallthrough;
 	case UAS_SIMPLE_TAG:
 		cmd->prio_attr = TCM_SIMPLE_TAG;
 		break;

drivers/usb/gadget/function/u_ether.c

@@ -321,7 +321,7 @@ static void rx_complete(struct usb_ep *ep, struct usb_request *req)
 	/* data overrun */
 	case -EOVERFLOW:
 		dev->net->stats.rx_over_errors++;
-		/* FALLTHROUGH */
+		fallthrough;
 
 	default:
 		dev->net->stats.rx_errors++;
@@ -444,7 +444,7 @@ static void tx_complete(struct usb_ep *ep, struct usb_request *req)
 	default:
 		dev->net->stats.tx_errors++;
 		VDBG(dev, "tx err %d\n", req->status);
-		/* FALLTHROUGH */
+		fallthrough;
 	case -ECONNRESET:		/* unlink */
 	case -ESHUTDOWN:		/* disconnect etc */
 		dev_kfree_skb_any(skb);

drivers/usb/gadget/function/u_serial.c

@@ -386,7 +386,7 @@ static void gs_rx_push(struct work_struct *work)
 			/* presumably a transient fault */
 			pr_warn("ttyGS%d: unexpected RX status %d\n",
 				port->port_num, req->status);
-			/* FALLTHROUGH */
+			fallthrough;
 		case 0:
 			/* normal completion */
 			break;
@@ -472,7 +472,7 @@ static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
 		/* presumably a transient fault */
 		pr_warn("%s: unexpected %s status %d\n",
 			__func__, ep->name, req->status);
-		/* FALL THROUGH */
+		fallthrough;
 	case 0:
 		/* normal completion */
 		gs_start_tx(port);
@@ -871,7 +871,7 @@ static void gs_console_complete_out(struct usb_ep *ep, struct usb_request *req)
 	default:
 		pr_warn("%s: unexpected %s status %d\n",
 			__func__, ep->name, req->status);
-		/* fall through */
+		fallthrough;
 	case 0:
 		/* normal completion */
 		spin_lock(&cons->lock);

drivers/usb/gadget/legacy/inode.c

@@ -312,7 +312,7 @@ get_ready_ep (unsigned f_flags, struct ep_data *epdata, bool is_write)
 	case STATE_EP_READY:			/* not configured yet */
 		if (is_write)
 			return 0;
-		// FALLTHRU
+		fallthrough;
 	case STATE_EP_UNBOUND:			/* clean disconnect */
 		break;
 	// case STATE_EP_DISABLED:		/* "can't happen" */
@@ -1084,7 +1084,7 @@ next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
 	case GADGETFS_DISCONNECT:
 		if (dev->state == STATE_DEV_SETUP)
 			dev->setup_abort = 1;
-		// FALL THROUGH
+		fallthrough;
 	case GADGETFS_CONNECT:
 		dev->ev_next = 0;
 		break;
@@ -1381,7 +1381,6 @@ gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 			make_qualifier (dev);
 			break;
 		case USB_DT_OTHER_SPEED_CONFIG:
-			// FALLTHROUGH
 		case USB_DT_CONFIG:
 			value = config_buf (dev,
 					w_value >> 8,
@@ -1718,7 +1717,7 @@ gadgetfs_suspend (struct usb_gadget *gadget)
 	case STATE_DEV_UNCONNECTED:
 		next_event (dev, GADGETFS_SUSPEND);
 		ep0_readable (dev);
-		/* FALLTHROUGH */
+		fallthrough;
 	default:
 		break;
 	}

drivers/usb/gadget/udc/dummy_hcd.c

@@ -567,12 +567,12 @@ static int dummy_enable(struct usb_ep *_ep,
 			if (max <= 1024)
 				break;
 			/* save a return statement */
-			/* fall through */
+			fallthrough;
 		case USB_SPEED_FULL:
 			if (max <= 64)
 				break;
 			/* save a return statement */
-			/* fall through */
+			fallthrough;
 		default:
 			if (max <= 8)
 				break;
@@ -590,7 +590,7 @@ static int dummy_enable(struct usb_ep *_ep,
 			if (max <= 1024)
 				break;
 			/* save a return statement */
-			/* fall through */
+			fallthrough;
 		case USB_SPEED_FULL:
 			if (max <= 1023)
 				break;
@@ -1943,7 +1943,7 @@ static void dummy_timer(struct timer_list *t)
 			 * this almost certainly polls too fast.
 			 */
 			limit = max(limit, periodic_bytes(dum, ep));
-			/* FALLTHROUGH */
+			fallthrough;
 
 		default:
 treat_control_like_bulk:
@@ -2252,7 +2252,7 @@ static int dummy_hub_control(
 					 "supported for USB 2.0 roothub\n");
 				goto error;
 			}
-			/* FALLS THROUGH */
+			fallthrough;
 		case USB_PORT_FEAT_RESET:
 			/* if it's already enabled, disable */
 			if (hcd->speed == HCD_USB3) {
@@ -2276,7 +2276,7 @@ static int dummy_hub_control(
 			 * interval? Is it still 50msec as for HS?
 			 */
 			dum_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
-			/* FALLS THROUGH */
+			fallthrough;
 		default:
 			if (hcd->speed == HCD_USB3) {
 				if ((dum_hcd->port_status &

drivers/usb/gadget/udc/goku_udc.c

@@ -125,11 +125,14 @@ goku_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
 	max = get_unaligned_le16(&desc->wMaxPacketSize);
 	switch (max) {
 	case 64:
-		mode++; /* fall through */
+		mode++;
+		fallthrough;
 	case 32:
-		mode++; /* fall through */
+		mode++;
+		fallthrough;
 	case 16:
-		mode++; /* fall through */
+		mode++;
+		fallthrough;
 	case 8:
 		mode <<= 3;
 		break;

drivers/usb/gadget/udc/omap_udc.c

@@ -2831,7 +2831,7 @@ static int omap_udc_probe(struct platform_device *pdev)
 				type = "integrated";
 				break;
 			}
-			/* FALL THROUGH */
+			fallthrough;
 		case 3:
 		case 11:
 		case 16:
@@ -2848,7 +2848,7 @@ static int omap_udc_probe(struct platform_device *pdev)
 		case 14:			/* transceiverless */
 			if (cpu_is_omap1710())
 				goto bad_on_1710;
-			/* FALL THROUGH */
+			fallthrough;
 		case 13:
 		case 15:
 			type = "no";

drivers/usb/gadget/udc/s3c2410_udc.c

@@ -308,7 +308,7 @@ static int s3c2410_udc_write_fifo(struct s3c2410_ep *ep,
 	switch (idx) {
 	default:
 		idx = 0;
-		/* fall through */
+		fallthrough;
 	case 0:
 		fifo_reg = S3C2410_UDC_EP0_FIFO_REG;
 		break;
@@ -413,7 +413,7 @@ static int s3c2410_udc_read_fifo(struct s3c2410_ep *ep,
 	switch (idx) {
 	default:
 		idx = 0;
-		/* fall through */
+		fallthrough;
 	case 0:
 		fifo_reg = S3C2410_UDC_EP0_FIFO_REG;
 		break;

drivers/usb/gadget/udc/tegra-xudc.c

@@ -2742,7 +2742,7 @@ static void tegra_xudc_handle_transfer_event(struct tegra_xudc *xudc,
 		ep_wait_for_stopped(xudc, ep_index);
 		ep->enq_ptr = ep->deq_ptr;
 		tegra_xudc_ep_nuke(ep, -EIO);
-		/* FALLTHROUGH */
+		fallthrough;
 	case TRB_CMPL_CODE_STREAM_NUMP_ERROR:
 	case TRB_CMPL_CODE_CTRL_DIR_ERR:
 	case TRB_CMPL_CODE_INVALID_STREAM_TYPE_ERR: