serial: drivers: switch ch and flag to u8

Now that the serial layer explicitly expects 'u8' for flags and
characters, propagate this type to drivers' (RX) routines.

Note that amba-pl011's, clps711x's and st-asc's 'ch' are left unchanged
because 'ch' contains not only a character, but whole status.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Hammer Hsieh <hammerh0314@gmail.com>
Acked-by: Richard GENOUD <richard.genoud@gmail.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/20230712081811.29004-11-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

34 files changed, 53 insertions, 48 deletions

diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c
index 185462fd959c..d756fcc884cb 100644
--- a/drivers/tty/serial/21285.c
+++ b/drivers/tty/serial/21285.c
@@ -117,7 +117,8 @@ static void serial21285_stop_rx(struct uart_port *port)
 static irqreturn_t serial21285_rx_chars(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	unsigned int status, ch, flag, rxs, max_count = 256;
+	unsigned int status, rxs, max_count = 256;
+	u8 ch, flag;
 
 	status = *CSR_UARTFLG;
 	while (!(status & 0x10) && max_count--) {
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 16aeb1420137..0533e75adca9 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -1706,8 +1706,7 @@ static void serial8250_enable_ms(struct uart_port *port)
 void serial8250_read_char(struct uart_8250_port *up, u16 lsr)
 {
 	struct uart_port *port = &up->port;
-	unsigned char ch;
-	char flag = TTY_NORMAL;
+	u8 ch, flag = TTY_NORMAL;
 
 	if (likely(lsr & UART_LSR_DR))
 		ch = serial_in(up, UART_RX);
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index 9f843d1cee40..6203ca1de769 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -110,8 +110,8 @@ static void altera_jtaguart_set_termios(struct uart_port *port,
 
 static void altera_jtaguart_rx_chars(struct uart_port *port)
 {
-	unsigned char ch;
 	unsigned long status;
+	u8 ch;
 
 	while ((status = readl(port->membase + ALTERA_JTAGUART_DATA_REG)) &
 	       ALTERA_JTAGUART_DATA_RVALID_MSK) {
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 9ce3d24af536..a9c41942190c 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -201,8 +201,8 @@ static void altera_uart_set_termios(struct uart_port *port,
 
 static void altera_uart_rx_chars(struct uart_port *port)
 {
-	unsigned char ch, flag;
 	unsigned short status;
+	u8 ch, flag;
 
 	while ((status = altera_uart_readl(port, ALTERA_UART_STATUS_REG)) &
 	       ALTERA_UART_STATUS_RRDY_MSK) {
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index a98fae2ca422..b5a7404cbacb 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -112,7 +112,8 @@ static void pl010_enable_ms(struct uart_port *port)
 
 static void pl010_rx_chars(struct uart_port *port)
 {
-	unsigned int status, ch, flag, rsr, max_count = 256;
+	unsigned int status, rsr, max_count = 256;
+	u8 ch, flag;
 
 	status = readb(port->membase + UART01x_FR);
 	while (UART_RX_DATA(status) && max_count--) {
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index c5c3f4674459..8bddc7470bcc 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -307,9 +307,10 @@ static void pl011_write(unsigned int val, const struct uart_amba_port *uap,
  */
 static int pl011_fifo_to_tty(struct uart_amba_port *uap)
 {
-	unsigned int ch, flag, fifotaken;
+	unsigned int ch, fifotaken;
 	int sysrq;
 	u16 status;
+	u8 flag;
 
 	for (fifotaken = 0; fifotaken != 256; fifotaken++) {
 		status = pl011_read(uap, REG_FR);
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c
index 915ee4b0d594..372db052573d 100644
--- a/drivers/tty/serial/apbuart.c
+++ b/drivers/tty/serial/apbuart.c
@@ -70,8 +70,9 @@ static void apbuart_stop_rx(struct uart_port *port)
 
 static void apbuart_rx_chars(struct uart_port *port)
 {
-	unsigned int status, ch, rsr, flag;
+	unsigned int status, rsr;
 	unsigned int max_chars = port->fifosize;
+	u8 ch, flag;
 
 	status = UART_GET_STATUS(port);
 
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 835903488acb..ad4ae19b6ce3 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -205,7 +205,7 @@ static void arc_serial_rx_chars(struct uart_port *port, unsigned int status)
 	 * controller, which is indeed the Rx-FIFO.
 	 */
 	do {
-		unsigned int ch, flg = TTY_NORMAL;
+		u8 ch, flg = TTY_NORMAL;
 
 		/*
 		 * This could be an Rx Intr for err (no data),
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 3467a875641a..ec54436969dc 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1516,8 +1516,8 @@ static void atmel_rx_from_ring(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	struct circ_buf *ring = &atmel_port->rx_ring;
-	unsigned int flg;
 	unsigned int status;
+	u8 flg;
 
 	while (ring->head != ring->tail) {
 		struct atmel_uart_char c;
diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index e49bc4019b50..be8b8788d2e2 100644
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -92,8 +92,9 @@ static irqreturn_t uart_clps711x_int_rx(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
 	struct clps711x_port *s = dev_get_drvdata(port->dev);
-	unsigned int status, flg;
+	unsigned int status;
 	u16 ch;
+	u8 flg;
 
 	for (;;) {
 		u32 sysflg = 0;
diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c
index ed197705f7ee..128b5479e813 100644
--- a/drivers/tty/serial/digicolor-usart.c
+++ b/drivers/tty/serial/digicolor-usart.c
@@ -136,8 +136,7 @@ static void digicolor_uart_rx(struct uart_port *port)
 	spin_lock_irqsave(&port->lock, flags);
 
 	while (1) {
-		u8 status, ch;
-		unsigned int ch_flag;
+		u8 status, ch, ch_flag;
 
 		if (digicolor_uart_rx_empty(port))
 			break;
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
index 6b7ed7f2f3ca..667f52e83277 100644
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
@@ -181,8 +181,8 @@ static inline void dz_receive_chars(struct dz_mux *mux)
 	struct dz_port *dport = &mux->dport[0];
 	struct uart_icount *icount;
 	int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
-	unsigned char ch, flag;
 	u16 status;
+	u8 ch, flag;
 	int i;
 
 	while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
diff --git a/drivers/tty/serial/ip22zilog.c b/drivers/tty/serial/ip22zilog.c
index b1f27e168135..845ff706bc59 100644
--- a/drivers/tty/serial/ip22zilog.c
+++ b/drivers/tty/serial/ip22zilog.c
@@ -248,8 +248,8 @@ static void ip22zilog_maybe_update_regs(struct uart_ip22zilog_port *up,
 static bool ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
 						  struct zilog_channel *channel)
 {
-	unsigned char ch, flag;
 	unsigned int r1;
+	u8 ch, flag;
 	bool push = up->port.state != NULL;
 
 	for (;;) {
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index 86dcbff8faa3..5efb2b593be3 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -215,8 +215,9 @@ static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx)
 
 static int max3100_handlerx(struct max3100_port *s, u16 rx)
 {
-	unsigned int ch, flg, status = 0;
+	unsigned int status = 0;
 	int ret = 0, cts;
+	u8 ch, flg;
 
 	if (rx & MAX3100_R && s->rx_enabled) {
 		dev_dbg(&s->spi->dev, "%s\n", __func__);
diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 997e39449766..416d553b73a7 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -669,7 +669,8 @@ static void max310x_batch_read(struct uart_port *port, u8 *rxbuf, unsigned int l
 static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen)
 {
 	struct max310x_one *one = to_max310x_port(port);
-	unsigned int sts, ch, flag, i;
+	unsigned int sts, i;
+	u8 ch, flag;
 
 	if (port->read_status_mask == MAX310X_LSR_RXOVR_BIT) {
 		/* We are just reading, happily ignoring any error conditions.
diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index 3239babe12a4..1666ce012e5e 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -281,7 +281,7 @@ static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
 static void mcf_rx_chars(struct mcf_uart *pp)
 {
 	struct uart_port *port = &pp->port;
-	unsigned char status, ch, flag;
+	u8 status, ch, flag;
 
 	while ((status = readb(port->membase + MCFUART_USR)) & MCFUART_USR_RXREADY) {
 		ch = readb(port->membase + MCFUART_URB);
diff --git a/drivers/tty/serial/milbeaut_usio.c b/drivers/tty/serial/milbeaut_usio.c
index 44988a2941b8..70a910085e93 100644
--- a/drivers/tty/serial/milbeaut_usio.c
+++ b/drivers/tty/serial/milbeaut_usio.c
@@ -148,8 +148,7 @@ static void mlb_usio_enable_ms(struct uart_port *port)
 static void mlb_usio_rx_chars(struct uart_port *port)
 {
 	struct tty_port *ttyport = &port->state->port;
-	unsigned long flag = 0;
-	char ch = 0;
+	u8 flag = 0, ch = 0;
 	u8 status;
 	int max_count = 2;
 
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index a368f4293967..2ef10997df18 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -616,9 +616,8 @@ static void mxs_auart_tx_chars(struct mxs_auart_port *s)
 
 static void mxs_auart_rx_char(struct mxs_auart_port *s)
 {
-	int flag;
 	u32 stat;
-	u8 c;
+	u8 c, flag;
 
 	c = mxs_read(s, REG_DATA);
 	stat = mxs_read(s, REG_STAT);
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 16ab7ea07fa3..2c11870fa894 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -442,7 +442,7 @@ static unsigned int check_modem_status(struct uart_omap_port *up)
 
 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 {
-	unsigned int flag;
+	u8 flag;
 
 	/*
 	 * Read one data character out to avoid stalling the receiver according
@@ -498,7 +498,7 @@ static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 
 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
 {
-	unsigned char ch = 0;
+	u8 ch;
 
 	if (!(lsr & UART_LSR_DR))
 		return;
diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c
index 444fa4b654ac..73c60f5ea027 100644
--- a/drivers/tty/serial/pxa.c
+++ b/drivers/tty/serial/pxa.c
@@ -90,7 +90,7 @@ static void serial_pxa_stop_rx(struct uart_port *port)
 
 static inline void receive_chars(struct uart_pxa_port *up, int *status)
 {
-	unsigned int ch, flag;
+	u8 ch, flag;
 	int max_count = 256;
 
 	do {
diff --git a/drivers/tty/serial/rp2.c b/drivers/tty/serial/rp2.c
index 749b873a5d99..de220ac8ca54 100644
--- a/drivers/tty/serial/rp2.c
+++ b/drivers/tty/serial/rp2.c
@@ -401,14 +401,14 @@ static void rp2_rx_chars(struct rp2_uart_port *up)
 
 	for (; bytes != 0; bytes--) {
 		u32 byte = readw(up->base + RP2_DATA_BYTE) | RP2_DUMMY_READ;
-		char ch = byte & 0xff;
+		u8 ch = byte & 0xff;
 
 		if (likely(!(byte & RP2_DATA_BYTE_EXCEPTION_MASK))) {
 			if (!uart_handle_sysrq_char(&up->port, ch))
 				uart_insert_char(&up->port, byte, 0, ch,
 						 TTY_NORMAL);
 		} else {
-			char flag = TTY_NORMAL;
+			u8 flag = TTY_NORMAL;
 
 			if (byte & RP2_DATA_BYTE_BREAK_m)
 				flag = TTY_BREAK;
diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
index 55107bbc00ce..ad011f1e2f4d 100644
--- a/drivers/tty/serial/sa1100.c
+++ b/drivers/tty/serial/sa1100.c
@@ -180,7 +180,8 @@ static void sa1100_enable_ms(struct uart_port *port)
 static void
 sa1100_rx_chars(struct sa1100_port *sport)
 {
-	unsigned int status, ch, flg;
+	unsigned int status;
+	u8 ch, flg;
 
 	status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
 		 UTSR0_TO_SM(UART_GET_UTSR0(sport));
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index b29e9dfd81a6..aa4a184f4a6c 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -759,9 +759,10 @@ finish:
 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
 {
 	struct uart_port *port = &ourport->port;
-	unsigned int ufcon, ch, flag, ufstat, uerstat;
+	unsigned int ufcon, ufstat, uerstat;
 	unsigned int fifocnt = 0;
 	int max_count = port->fifosize;
+	u8 ch, flag;
 
 	while (max_count-- > 0) {
 		/*
diff --git a/drivers/tty/serial/sb1250-duart.c b/drivers/tty/serial/sb1250-duart.c
index b6de0dc51f29..f3cd69346482 100644
--- a/drivers/tty/serial/sb1250-duart.c
+++ b/drivers/tty/serial/sb1250-duart.c
@@ -331,8 +331,9 @@ static void sbd_receive_chars(struct sbd_port *sport)
 {
 	struct uart_port *uport = &sport->port;
 	struct uart_icount *icount;
-	unsigned int status, ch, flag;
+	unsigned int status;
 	int count;
+	u8 ch, flag;
 
 	for (count = 16; count; count--) {
 		status = read_sbdchn(sport, R_DUART_STATUS);
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 2e7e7c409cf2..cfffc730ba34 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -578,8 +578,9 @@ static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
 				unsigned int iir)
 {
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
-	unsigned int lsr = 0, ch, flag, bytes_read, i;
+	unsigned int lsr = 0, bytes_read, i;
 	bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
+	u8 ch, flag;
 
 	if (unlikely(rxlen >= sizeof(s->buf))) {
 		dev_warn_ratelimited(port->dev,
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index 4f2fc5f7bb19..31ee46eba580 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -383,8 +383,7 @@ static void sccnxp_set_bit(struct uart_port *port, int sig, int state)
 
 static void sccnxp_handle_rx(struct uart_port *port)
 {
-	u8 sr;
-	unsigned int ch, flag;
+	u8 sr, ch, flag;
 
 	for (;;) {
 		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 1cf08b33456c..813ae97159c4 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -434,10 +434,10 @@ static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud)
 	return 0;
 }
 
-static char tegra_uart_decode_rx_error(struct tegra_uart_port *tup,
+static u8 tegra_uart_decode_rx_error(struct tegra_uart_port *tup,
 			unsigned long lsr)
 {
-	char flag = TTY_NORMAL;
+	u8 flag = TTY_NORMAL;
 
 	if (unlikely(lsr & TEGRA_UART_LSR_ANY)) {
 		if (lsr & UART_LSR_OE) {
@@ -642,9 +642,8 @@ static void tegra_uart_handle_rx_pio(struct tegra_uart_port *tup,
 		struct tty_port *port)
 {
 	do {
-		char flag = TTY_NORMAL;
 		unsigned long lsr = 0;
-		unsigned char ch;
+		u8 ch, flag = TTY_NORMAL;
 
 		lsr = tegra_uart_read(tup, UART_LSR);
 		if (!(lsr & UART_LSR_DR))
diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_txx9.c
index eab387b01e36..be08fb6f749c 100644
--- a/drivers/tty/serial/serial_txx9.c
+++ b/drivers/tty/serial/serial_txx9.c
@@ -246,11 +246,10 @@ static void serial_txx9_initialize(struct uart_port *up)
 static inline void
 receive_chars(struct uart_port *up, unsigned int *status)
 {
-	unsigned char ch;
 	unsigned int disr = *status;
 	int max_count = 256;
-	char flag;
 	unsigned int next_ignore_status_mask;
+	u8 ch, flag;
 
 	do {
 		ch = sio_in(up, TXX9_SIRFIFO);
diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c
index 1f565a216e74..c00080f12cab 100644
--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -402,9 +402,9 @@ static char __ssp_receive_char(struct sifive_serial_port *ssp, char *is_empty)
  */
 static void __ssp_receive_chars(struct sifive_serial_port *ssp)
 {
-	unsigned char ch;
 	char is_empty;
 	int c;
+	u8 ch;
 
 	for (c = SIFIVE_RX_FIFO_DEPTH; c > 0; --c) {
 		ch = __ssp_receive_char(ssp, &is_empty);
diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index b58f51296ace..8f6fd1cd91d7 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -558,7 +558,7 @@ static void sprd_break_ctl(struct uart_port *port, int break_state)
 }
 
 static int handle_lsr_errors(struct uart_port *port,
-			     unsigned int *flag,
+			     u8 *flag,
 			     unsigned int *lsr)
 {
 	int ret = 0;
@@ -594,7 +594,8 @@ static inline void sprd_rx(struct uart_port *port)
 	struct sprd_uart_port *sp = container_of(port, struct sprd_uart_port,
 						 port);
 	struct tty_port *tty = &port->state->port;
-	unsigned int ch, flag, lsr, max_count = SPRD_TIMEOUT;
+	unsigned int lsr, max_count = SPRD_TIMEOUT;
+	u8 ch, flag;
 
 	if (sp->rx_dma.enable) {
 		sprd_uart_dma_irq(port);
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index aa471c9c24d9..387bc69bb1fe 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -250,7 +250,7 @@ static void asc_receive_chars(struct uart_port *port)
 	struct tty_port *tport = &port->state->port;
 	unsigned long status, mode;
 	unsigned long c = 0;
-	char flag;
+	u8 flag;
 	bool ignore_pe = false;
 
 	/*
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index e9e11a259621..be47cd343cf6 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -321,7 +321,7 @@ static bool stm32_usart_pending_rx_pio(struct uart_port *port, u32 *sr)
 	return false;
 }
 
-static unsigned long stm32_usart_get_char_pio(struct uart_port *port)
+static u8 stm32_usart_get_char_pio(struct uart_port *port)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
@@ -338,10 +338,9 @@ static unsigned int stm32_usart_receive_chars_pio(struct uart_port *port)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
-	unsigned long c;
 	unsigned int size = 0;
 	u32 sr;
-	char flag;
+	u8 c, flag;
 
 	while (stm32_usart_pending_rx_pio(port, &sr)) {
 		sr |= USART_SR_DUMMY_RX;
diff --git a/drivers/tty/serial/sunplus-uart.c b/drivers/tty/serial/sunplus-uart.c
index 727942c43c45..3aacd5eb414c 100644
--- a/drivers/tty/serial/sunplus-uart.c
+++ b/drivers/tty/serial/sunplus-uart.c
@@ -231,7 +231,7 @@ static void transmit_chars(struct uart_port *port)
 static void receive_chars(struct uart_port *port)
 {
 	unsigned int lsr = readl(port->membase + SUP_UART_LSR);
-	unsigned int ch, flag;
+	u8 ch, flag;
 
 	do {
 		ch = readl(port->membase + SUP_UART_DATA);
diff --git a/drivers/tty/serial/zs.c b/drivers/tty/serial/zs.c
index 730c648e32ff..65ca4da6e368 100644
--- a/drivers/tty/serial/zs.c
+++ b/drivers/tty/serial/zs.c
@@ -539,8 +539,9 @@ static void zs_receive_chars(struct zs_port *zport)
 	struct uart_port *uport = &zport->port;
 	struct zs_scc *scc = zport->scc;
 	struct uart_icount *icount;
-	unsigned int avail, status, ch, flag;
+	unsigned int avail, status;
 	int count;
+	u8 ch, flag;
 
 	for (count = 16; count; count--) {
 		spin_lock(&scc->zlock);