treewide: 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/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

20 files changed, 23 insertions, 26 deletions

diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 2a0e51a20e34..92c9a476defc 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -492,7 +492,7 @@ static void xencons_backend_changed(struct xenbus_device *dev,
 	case XenbusStateClosed:
 		if (dev->state == XenbusStateClosed)
 			break;
-		/* fall through - Missed the backend's CLOSING state. */
+		fallthrough;	/* Missed the backend's CLOSING state */
 	case XenbusStateClosing:
 		xenbus_frontend_closed(dev);
 		break;
diff --git a/drivers/tty/mips_ejtag_fdc.c b/drivers/tty/mips_ejtag_fdc.c
index 21e76a2ec182..a8e19b4833bf 100644
--- a/drivers/tty/mips_ejtag_fdc.c
+++ b/drivers/tty/mips_ejtag_fdc.c
@@ -243,7 +243,7 @@ done:
 		/* Fall back to a 3 byte encoding */
 		word.bytes = 3;
 		word.word &= 0x00ffffff;
-		/* Fall through */
+		fallthrough;
 	case 3:
 		/* 3 byte encoding */
 		word.word |= 0x82000000;
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 0a29a94ec438..35cf12147e39 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1584,7 +1584,7 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, const u8 *data, int clen)
 			gsm_process_modem(tty, dlci, modem, clen);
 			tty_kref_put(tty);
 		}
-		/* Fall through */
+		fallthrough;
 	case 1:		/* Line state will go via DLCI 0 controls only */
 	default:
 		tty_insert_flip_string(port, data, len);
@@ -1986,7 +1986,7 @@ static void gsm1_receive(struct gsm_mux *gsm, unsigned char c)
 		gsm->address = 0;
 		gsm->state = GSM_ADDRESS;
 		gsm->fcs = INIT_FCS;
-		/* Fall through */
+		fallthrough;
 	case GSM_ADDRESS:	/* Address continuation */
 		gsm->fcs = gsm_fcs_add(gsm->fcs, c);
 		if (gsm_read_ea(&gsm->address, c))
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index b09eac4b6d64..8e975cb29833 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -602,7 +602,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
 		case TCOFLUSH:
 			flush_tx_queue(tty);
 		}
-		/* fall through - to default */
+		fallthrough;	/* to default */
 
 	default:
 		error = n_tty_ioctl_helper(tty, file, cmd, arg);
diff --git a/drivers/tty/n_r3964.c b/drivers/tty/n_r3964.c
index f75696f0ee2d..934dd2fb2ec8 100644
--- a/drivers/tty/n_r3964.c
+++ b/drivers/tty/n_r3964.c
@@ -605,7 +605,6 @@ static void receive_char(struct r3964_info *pInfo, const unsigned char c)
 		}
 		break;
 	case R3964_WAIT_FOR_RX_REPEAT:
-		/* FALLTHROUGH */
 	case R3964_IDLE:
 		if (c == STX) {
 			/* Prevent rx_queue from overflow: */
diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c
index db88dee3a399..f8e99995eee9 100644
--- a/drivers/tty/serial/8250/8250_em.c
+++ b/drivers/tty/serial/8250/8250_em.c
@@ -39,7 +39,7 @@ static void serial8250_em_serial_out(struct uart_port *p, int offset, int value)
 		break;
 	case UART_IER: /* IER @ 0x04 */
 		value &= 0x0f; /* only 4 valid bits - not Xscale */
-		/* fall-through */
+		fallthrough;
 	case UART_DLL_EM: /* DLL @ 0x24 (+9) */
 	case UART_DLM_EM: /* DLM @ 0x28 (+9) */
 		writel(value, p->membase + (offset << 2));
diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index d1d253c4b518..31c9e83ea3cb 100644
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -255,7 +255,7 @@ static void fintek_8250_set_irq_mode(struct fintek_8250 *pdata, bool is_level)
 	case CHIP_ID_F81866:
 		sio_write_mask_reg(pdata, F81866_FIFO_CTRL, F81866_IRQ_MODE1,
 				   0);
-		/* fall through */
+		fallthrough;
 	case CHIP_ID_F81865:
 		sio_write_mask_reg(pdata, F81866_IRQ_MODE, F81866_IRQ_SHARE,
 				   F81866_IRQ_SHARE);
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 1a74d511b02a..3eb2d485eaeb 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -631,7 +631,7 @@ pci_timedia_setup(struct serial_private *priv,
 		break;
 	case 3:
 		offset = board->uart_offset;
-		/* FALLTHROUGH */
+		fallthrough;
 	case 4: /* BAR 2 */
 	case 5: /* BAR 3 */
 	case 6: /* BAR 4 */
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 09475695effd..06028da9bc6a 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -1872,7 +1872,7 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
 	switch (iir & 0x3f) {
 	case UART_IIR_RX_TIMEOUT:
 		serial8250_rx_dma_flush(up);
-		/* fall-through */
+		fallthrough;
 	case UART_IIR_RLSI:
 		return true;
 	}
diff --git a/drivers/tty/serial/8250/8250_uniphier.c b/drivers/tty/serial/8250/8250_uniphier.c
index e0b73a5402db..a2978abab0db 100644
--- a/drivers/tty/serial/8250/8250_uniphier.c
+++ b/drivers/tty/serial/8250/8250_uniphier.c
@@ -75,7 +75,7 @@ static unsigned int uniphier_serial_in(struct uart_port *p, int offset)
 		break;
 	case UART_LCR:
 		valshift = 8;
-		/* fall through */
+		fallthrough;
 	case UART_MCR:
 		offset = UNIPHIER_UART_LCR_MCR;
 		break;
@@ -101,7 +101,7 @@ static void uniphier_serial_out(struct uart_port *p, int offset, int value)
 	case UART_SCR:
 		/* No SCR for this hardware.  Use CHAR as a scratch register */
 		valshift = 8;
-		/* fall through */
+		fallthrough;
 	case UART_FCR:
 		offset = UNIPHIER_UART_CHAR_FCR;
 		break;
@@ -109,7 +109,7 @@ static void uniphier_serial_out(struct uart_port *p, int offset, int value)
 		valshift = 8;
 		/* Divisor latch access bit does not exist. */
 		value &= ~UART_LCR_DLAB;
-		/* fall through */
+		fallthrough;
 	case UART_MCR:
 		offset = UNIPHIER_UART_LCR_MCR;
 		break;
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index e43471b33710..bb5fc8bdd57a 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1845,7 +1845,7 @@ static void atmel_get_ip_name(struct uart_port *port)
 		version = atmel_uart_readl(port, ATMEL_US_VERSION);
 		switch (version) {
 		case 0x814:	/* sama5d2 */
-			/* fall through */
+			fallthrough;
 		case 0x701:	/* sama5d4 */
 			atmel_port->fidi_min = 3;
 			atmel_port->fidi_max = 65535;
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 8573fc9cb0cd..76b94d0ff586 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -587,7 +587,6 @@ static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 			transmit_chars(up, lsr);
 			break;
 		case UART_IIR_RX_TIMEOUT:
-			/* FALLTHROUGH */
 		case UART_IIR_RDI:
 			serial_omap_rdi(up, lsr);
 			break;
@@ -598,7 +597,6 @@ static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 			/* simply try again */
 			break;
 		case UART_IIR_XOFF:
-			/* FALLTHROUGH */
 		default:
 			break;
 		}
diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c
index b5ef86ae2746..85366e059258 100644
--- a/drivers/tty/serial/rda-uart.c
+++ b/drivers/tty/serial/rda-uart.c
@@ -259,7 +259,7 @@ static void rda_uart_set_termios(struct uart_port *port,
 	case CS5:
 	case CS6:
 		dev_warn(port->dev, "bit size not supported, using 7 bits\n");
-		/* Fall through */
+		fallthrough;
 	case CS7:
 		ctrl &= ~RDA_UART_DBITS_8;
 		break;
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index b87914ae6da8..bd13014a1c53 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -876,7 +876,7 @@ static irqreturn_t tegra_uart_isr(int irq, void *data)
 				tegra_uart_write(tup, ier, UART_IER);
 				break;
 			}
-			/* Fall through */
+			fallthrough;
 		case 2: /* Receive */
 			if (!tup->use_rx_pio) {
 				is_rx_start = tup->rx_in_progress;
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 3403dd790517..f797c971cd82 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2101,7 +2101,7 @@ uart_set_options(struct uart_port *port, struct console *co,
 	switch (parity) {
 	case 'o': case 'O':
 		termios.c_cflag |= PARODD;
-		/*fall through*/
+		fallthrough;
 	case 'e': case 'E':
 		termios.c_cflag |= PARENB;
 		break;
diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c
index 8ce9a7a256e5..319e5ceb6130 100644
--- a/drivers/tty/serial/sunsu.c
+++ b/drivers/tty/serial/sunsu.c
@@ -514,7 +514,7 @@ static void receive_kbd_ms_chars(struct uart_sunsu_port *up, int is_break)
 			switch (ret) {
 			case 2:
 				sunsu_change_mouse_baud(up);
-				/* fallthru */
+				fallthrough;
 			case 1:
 				break;
 
diff --git a/drivers/tty/serial/sunzilog.c b/drivers/tty/serial/sunzilog.c
index 7ea06bbc6197..001e19d7c17d 100644
--- a/drivers/tty/serial/sunzilog.c
+++ b/drivers/tty/serial/sunzilog.c
@@ -306,7 +306,7 @@ static void sunzilog_kbdms_receive_chars(struct uart_sunzilog_port *up,
 		switch (ret) {
 		case 2:
 			sunzilog_change_mouse_baud(up);
-			/* fallthru */
+			fallthrough;
 		case 1:
 			break;
 
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 2833f1418d6d..a9b1ee27183a 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -544,7 +544,7 @@ static int cdns_uart_clk_notifier_cb(struct notifier_block *nb,
 
 		cdns_uart->baud = cdns_uart_set_baud_rate(cdns_uart->port,
 				cdns_uart->baud);
-		/* fall through */
+		fallthrough;
 	case ABORT_RATE_CHANGE:
 		if (!locked)
 			spin_lock_irqsave(&cdns_uart->port->lock, flags);
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 9245fffdbceb..e18f318586ab 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -866,7 +866,7 @@ static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg)
 			ld->ops->flush_buffer(tty);
 			tty_unthrottle(tty);
 		}
-		/* fall through */
+		fallthrough;
 	case TCOFLUSH:
 		tty_driver_flush_buffer(tty);
 		break;
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index ccb533fd00a2..d8b9363b81c1 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -1553,7 +1553,7 @@ static void csi_J(struct vc_data *vc, int vpar)
 			break;
 		case 3: /* include scrollback */
 			flush_scrollback(vc);
-			/* fallthrough */
+			fallthrough;
 		case 2: /* erase whole display */
 			vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
 			count = vc->vc_cols * vc->vc_rows;
@@ -2167,7 +2167,7 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
 		lf(vc);
 		if (!is_kbd(vc, lnm))
 			return;
-		/* fall through */
+		fallthrough;
 	case 13:
 		cr(vc);
 		return;
@@ -2306,7 +2306,7 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
 			return;
 		}
 		vc->vc_priv = EPecma;
-		/* fall through */
+		fallthrough;
 	case ESgetpars:
 		if (c == ';' && vc->vc_npar < NPAR - 1) {
 			vc->vc_npar++;