diff --git a/drivers/tty/goldfish.c b/drivers/tty/goldfish.c
index 5ed19a9857ad..ad13532e92fe 100644
--- a/drivers/tty/goldfish.c
+++ b/drivers/tty/goldfish.c
@@ -434,7 +434,7 @@ static int goldfish_tty_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_GOLDFISH_TTY_EARLY_CONSOLE
-static void gf_early_console_putchar(struct uart_port *port, int ch)
+static void gf_early_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	__raw_writel(ch, port->membase);
 }
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
index 8e0edb7d93fd..bd61f9372d83 100644
--- a/drivers/tty/hvc/hvc_dcc.c
+++ b/drivers/tty/hvc/hvc_dcc.c
@@ -15,7 +15,7 @@
 #define DCC_STATUS_RX		(1 << 30)
 #define DCC_STATUS_TX		(1 << 29)
 
-static void dcc_uart_console_putchar(struct uart_port *port, int ch)
+static void dcc_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (__dcc_getstatus() & DCC_STATUS_TX)
 		cpu_relax();
diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c
index 09baef4ccc39..7520cc02fd4d 100644
--- a/drivers/tty/serial/21285.c
+++ b/drivers/tty/serial/21285.c
@@ -403,7 +403,7 @@ static void serial21285_setup_ports(void)
 }
 
 #ifdef CONFIG_SERIAL_21285_CONSOLE
-static void serial21285_console_putchar(struct uart_port *port, int ch)
+static void serial21285_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (*CSR_UARTFLG & 0x20)
 		barrier();
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index c171ce6db691..e52585064565 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -86,7 +86,7 @@ static void serial8250_early_out(struct uart_port *port, int offset, int value)
 
 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 
-static void serial_putc(struct uart_port *port, int c)
+static void serial_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned int status;
 
diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
index 65402d05eff9..cff91aa03f29 100644
--- a/drivers/tty/serial/8250/8250_ingenic.c
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -52,7 +52,7 @@ static void early_out(struct uart_port *port, int offset, uint8_t value)
 	writel(value, port->membase + (offset << 2));
 }
 
-static void ingenic_early_console_putc(struct uart_port *port, int c)
+static void ingenic_early_console_putc(struct uart_port *port, unsigned char c)
 {
 	uint8_t lsr;
 
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 3b12bfc1ed67..6f24eeeb9050 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3296,7 +3296,7 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
 
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index 37bffe406b18..1c16345d0a1f 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -298,7 +298,7 @@ static struct altera_jtaguart altera_jtaguart_ports[ALTERA_JTAGUART_MAXPORTS];
 #if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE)
 
 #if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE_BYPASS)
-static void altera_jtaguart_console_putc(struct uart_port *port, int c)
+static void altera_jtaguart_console_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned long status;
 	unsigned long flags;
@@ -318,7 +318,7 @@ static void altera_jtaguart_console_putc(struct uart_port *port, int c)
 	spin_unlock_irqrestore(&port->lock, flags);
 }
 #else
-static void altera_jtaguart_console_putc(struct uart_port *port, int c)
+static void altera_jtaguart_console_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned long flags;
 
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 64a352b40197..8b749ed557c6 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -438,7 +438,7 @@ static struct altera_uart altera_uart_ports[CONFIG_SERIAL_ALTERA_UART_MAXPORTS];
 
 #if defined(CONFIG_SERIAL_ALTERA_UART_CONSOLE)
 
-static void altera_uart_console_putc(struct uart_port *port, int c)
+static void altera_uart_console_putc(struct uart_port *port, unsigned char c)
 {
 	while (!(altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
 		 ALTERA_UART_STATUS_TRDY_MSK))
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 47654073123d..896f66cacf8b 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -556,7 +556,7 @@ static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
 
-static void pl010_console_putchar(struct uart_port *port, int ch)
+static void pl010_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_amba_port *uap =
 		container_of(port, struct uart_amba_port, port);
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index ba053a68529f..51ecb050ae40 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2255,7 +2255,7 @@ static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
 
-static void pl011_console_putchar(struct uart_port *port, int ch)
+static void pl011_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
@@ -2471,7 +2471,7 @@ static struct console amba_console = {
 
 #define AMBA_CONSOLE	(&amba_console)
 
-static void qdf2400_e44_putc(struct uart_port *port, int c)
+static void qdf2400_e44_putc(struct uart_port *port, unsigned char c)
 {
 	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
 		cpu_relax();
@@ -2487,7 +2487,7 @@ static void qdf2400_e44_early_write(struct console *con, const char *s, unsigned
 	uart_console_write(&dev->port, s, n, qdf2400_e44_putc);
 }
 
-static void pl011_putc(struct uart_port *port, int c)
+static void pl011_putc(struct uart_port *port, unsigned char c)
 {
 	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
 		cpu_relax();
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c
index d8c937bdf3f9..9ef82d870ff2 100644
--- a/drivers/tty/serial/apbuart.c
+++ b/drivers/tty/serial/apbuart.c
@@ -413,7 +413,7 @@ static void apbuart_flush_fifo(struct uart_port *port)
 
 #ifdef CONFIG_SERIAL_GRLIB_GAISLER_APBUART_CONSOLE
 
-static void apbuart_console_putchar(struct uart_port *port, int ch)
+static void apbuart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	unsigned int status;
 	do {
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 8cabe50c4a33..6269dbf93546 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -613,7 +613,7 @@ static void ar933x_uart_wait_xmitr(struct ar933x_uart_port *up)
 	} while ((status & AR933X_UART_DATA_TX_CSR) == 0);
 }
 
-static void ar933x_uart_console_putchar(struct uart_port *port, int ch)
+static void ar933x_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct ar933x_uart_port *up =
 		container_of(port, struct ar933x_uart_port, port);
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 596217d10d5c..2a09e92ef9ed 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -508,7 +508,7 @@ static int arc_serial_console_setup(struct console *co, char *options)
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 
-static void arc_serial_console_putchar(struct uart_port *port, int ch)
+static void arc_serial_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (!(UART_GET_STATUS(port) & TXEMPTY))
 		cpu_relax();
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 2d09a89974a2..ab79128dbdb5 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2541,7 +2541,7 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port,
 }
 
 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
-static void atmel_console_putchar(struct uart_port *port, int ch)
+static void atmel_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
 		cpu_relax();
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
index 6471a54b616b..53b43174aa40 100644
--- a/drivers/tty/serial/bcm63xx_uart.c
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -681,7 +681,7 @@ static void wait_for_xmitr(struct uart_port *port)
 /*
  * output given char
  */
-static void bcm_console_putchar(struct uart_port *port, int ch)
+static void bcm_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	wait_for_xmitr(port);
 	bcm_uart_writel(port, ch, UART_FIFO_REG);
diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index 95abc6faa3d5..b9b66ad31a08 100644
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -348,7 +348,7 @@ static const struct uart_ops uart_clps711x_ops = {
 };
 
 #ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
-static void uart_clps711x_console_putchar(struct uart_port *port, int ch)
+static void uart_clps711x_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct clps711x_port *s = dev_get_drvdata(port->dev);
 	u32 sysflg = 0;
diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c
index 13ac36e2da4f..6d70fea76bb3 100644
--- a/drivers/tty/serial/digicolor-usart.c
+++ b/drivers/tty/serial/digicolor-usart.c
@@ -381,7 +381,7 @@ static const struct uart_ops digicolor_uart_ops = {
 	.request_port	= digicolor_uart_request_port,
 };
 
-static void digicolor_uart_console_putchar(struct uart_port *port, int ch)
+static void digicolor_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (digicolor_uart_tx_full(port))
 		cpu_relax();
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
index e9edabc5a211..2e21acf39720 100644
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
@@ -802,7 +802,7 @@ static void __init dz_init_ports(void)
  * restored.  Welcome to the world of PDP-11!
  * -------------------------------------------------------------------
  */
-static void dz_console_putchar(struct uart_port *uport, int ch)
+static void dz_console_putchar(struct uart_port *uport, unsigned char ch)
 {
 	struct dz_port *dport = to_dport(uport);
 	unsigned long flags;
diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c
index fa096c10b591..fcdec5f42376 100644
--- a/drivers/tty/serial/earlycon-arm-semihost.c
+++ b/drivers/tty/serial/earlycon-arm-semihost.c
@@ -21,7 +21,7 @@
 /*
  * Semihosting-based debug console
  */
-static void smh_putc(struct uart_port *port, int c)
+static void smh_putc(struct uart_port *port, unsigned char c)
 {
 #ifdef CONFIG_ARM64
 	asm volatile("mov  x1, %0\n"
diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c
index ce81523c3113..27afb0b74ea7 100644
--- a/drivers/tty/serial/earlycon-riscv-sbi.c
+++ b/drivers/tty/serial/earlycon-riscv-sbi.c
@@ -10,7 +10,7 @@
 #include <linux/serial_core.h>
 #include <asm/sbi.h>
 
-static void sbi_putc(struct uart_port *port, int c)
+static void sbi_putc(struct uart_port *port, unsigned char c)
 {
 	sbi_console_putchar(c);
 }
diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c
index e72cba085743..98bb0c315e13 100644
--- a/drivers/tty/serial/fsl_linflexuart.c
+++ b/drivers/tty/serial/fsl_linflexuart.c
@@ -553,7 +553,7 @@ static const struct uart_ops linflex_pops = {
 static struct uart_port *linflex_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE
-static void linflex_console_putchar(struct uart_port *port, int ch)
+static void linflex_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	unsigned long cr;
 
@@ -578,7 +578,7 @@ static void linflex_console_putchar(struct uart_port *port, int ch)
 	}
 }
 
-static void linflex_earlycon_putchar(struct uart_port *port, int ch)
+static void linflex_earlycon_putchar(struct uart_port *port, unsigned char ch)
 {
 	unsigned long flags;
 	char *ret;
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 7d90c5a530ee..87789872f400 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2333,13 +2333,13 @@ static const struct uart_ops lpuart32_pops = {
 static struct lpuart_port *lpuart_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
-static void lpuart_console_putchar(struct uart_port *port, int ch)
+static void lpuart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
 	writeb(ch, port->membase + UARTDR);
 }
 
-static void lpuart32_console_putchar(struct uart_port *port, int ch)
+static void lpuart32_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
 	lpuart32_write(port, ch, UARTDATA);
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 0b467ce8d737..fd38e6ed4fda 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1968,7 +1968,7 @@ static const struct uart_ops imx_uart_pops = {
 static struct imx_port *imx_uart_ports[UART_NR];
 
 #if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE)
-static void imx_uart_console_putchar(struct uart_port *port, int ch)
+static void imx_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct imx_port *sport = (struct imx_port *)port;
 
diff --git a/drivers/tty/serial/imx_earlycon.c b/drivers/tty/serial/imx_earlycon.c
index 795606e1a22f..7aab38b2bd8c 100644
--- a/drivers/tty/serial/imx_earlycon.c
+++ b/drivers/tty/serial/imx_earlycon.c
@@ -16,7 +16,7 @@
 #define UTS_TXFULL (1<<4) /* TxFIFO full */
 #define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
 
-static void imx_uart_console_early_putchar(struct uart_port *port, int ch)
+static void imx_uart_console_early_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (readl_relaxed(port->membase + IMX21_UTS) & UTS_TXFULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/ip22zilog.c b/drivers/tty/serial/ip22zilog.c
index f4dc5fe4ba92..655e64b26852 100644
--- a/drivers/tty/serial/ip22zilog.c
+++ b/drivers/tty/serial/ip22zilog.c
@@ -990,7 +990,7 @@ static struct zilog_layout * __init get_zs(int chip)
 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
 
 #ifdef CONFIG_SERIAL_IP22_ZILOG_CONSOLE
-static void ip22zilog_put_char(struct uart_port *port, int ch)
+static void ip22zilog_put_char(struct uart_port *port, unsigned char ch)
 {
 	struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
 	int loops = ZS_PUT_CHAR_MAX_DELAY;
diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
index 3e324d3f0a6d..a3120c3347dd 100644
--- a/drivers/tty/serial/lantiq.c
+++ b/drivers/tty/serial/lantiq.c
@@ -598,7 +598,7 @@ static const struct uart_ops lqasc_pops = {
 
 #ifdef CONFIG_SERIAL_LANTIQ_CONSOLE
 static void
-lqasc_console_putchar(struct uart_port *port, int ch)
+lqasc_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	int fifofree;
 
diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c
index 7f74bf7bdcff..328b50521f14 100644
--- a/drivers/tty/serial/liteuart.c
+++ b/drivers/tty/serial/liteuart.c
@@ -93,7 +93,7 @@ static void liteuart_timer(struct timer_list *t)
 	mod_timer(&uart->timer, jiffies + uart_poll_timeout(port));
 }
 
-static void liteuart_putchar(struct uart_port *port, int ch)
+static void liteuart_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (litex_read8(port->membase + OFF_TXFULL))
 		cpu_relax();
diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index 07c4161eb4cc..b7b489c68c36 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -122,7 +122,7 @@ static void wait_for_xmit_ready(struct uart_port *port)
 	}
 }
 
-static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
+static void lpc32xx_hsuart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	wait_for_xmit_ready(port);
 	writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 45e00d928253..2bf1c57e0981 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -513,7 +513,7 @@ static void meson_uart_enable_tx_engine(struct uart_port *port)
 	writel(val, port->membase + AML_UART_CONTROL);
 }
 
-static void meson_console_putchar(struct uart_port *port, int ch)
+static void meson_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/milbeaut_usio.c b/drivers/tty/serial/milbeaut_usio.c
index 8f2cab7f66ad..347088bb380e 100644
--- a/drivers/tty/serial/milbeaut_usio.c
+++ b/drivers/tty/serial/milbeaut_usio.c
@@ -400,7 +400,7 @@ static const struct uart_ops mlb_usio_ops = {
 
 #ifdef CONFIG_SERIAL_MILBEAUT_USIO_CONSOLE
 
-static void mlb_usio_console_putchar(struct uart_port *port, int c)
+static void mlb_usio_console_putchar(struct uart_port *port, unsigned char c)
 {
 	while (!(readb(port->membase + MLB_USIO_REG_SSR) & MLB_USIO_SSR_TDRE))
 		cpu_relax();
diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c
index 587b42f754cb..5e9429dcc51f 100644
--- a/drivers/tty/serial/mps2-uart.c
+++ b/drivers/tty/serial/mps2-uart.c
@@ -432,7 +432,7 @@ static const struct uart_ops mps2_uart_pops = {
 static DEFINE_IDR(ports_idr);
 
 #ifdef CONFIG_SERIAL_MPS2_UART_CONSOLE
-static void mps2_uart_console_putchar(struct uart_port *port, int ch)
+static void mps2_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (mps2_uart_read8(port, UARTn_STATE) & UARTn_STATE_TX_FULL)
 		cpu_relax();
@@ -484,7 +484,7 @@ static struct console mps2_uart_console = {
 
 #define MPS2_SERIAL_CONSOLE (&mps2_uart_console)
 
-static void mps2_early_putchar(struct uart_port *port, int ch)
+static void mps2_early_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (readb(port->membase + UARTn_STATE) & UARTn_STATE_TX_FULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index ab226da75f7b..b5705da31878 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -598,7 +598,7 @@ static const struct uart_ops mvebu_uart_ops = {
 
 #ifdef CONFIG_SERIAL_MVEBU_CONSOLE
 /* Early Console */
-static void mvebu_uart_putc(struct uart_port *port, int c)
+static void mvebu_uart_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned int st;
 
@@ -659,7 +659,7 @@ static void wait_for_xmite(struct uart_port *port)
 				  (val & STAT_TX_EMP), 1, 10000);
 }
 
-static void mvebu_uart_console_putchar(struct uart_port *port, int ch)
+static void mvebu_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	wait_for_xmitr(port);
 	writel(ch, port->membase + UART_TSH(port));
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index ac45f3386e97..1944daf8593a 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -1305,7 +1305,7 @@ static const struct uart_ops mxs_auart_ops = {
 static struct mxs_auart_port *auart_port[MXS_AUART_PORTS];
 
 #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
-static void mxs_auart_console_putchar(struct uart_port *port, int ch)
+static void mxs_auart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct mxs_auart_port *s = to_auart_port(port);
 	unsigned int to = 1000;
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 0862941862c8..7074670cf81d 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1194,7 +1194,7 @@ static void omap_serial_early_out(struct uart_port *port, int offset,
 	writew(value, port->membase + offset);
 }
 
-static void omap_serial_early_putc(struct uart_port *port, int c)
+static void omap_serial_early_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned int status;
 
@@ -1238,7 +1238,7 @@ static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
 
 static struct uart_driver serial_omap_reg;
 
-static void serial_omap_console_putchar(struct uart_port *port, int ch)
+static void serial_omap_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_omap_port *up = to_uart_omap_port(port);
 
diff --git a/drivers/tty/serial/owl-uart.c b/drivers/tty/serial/owl-uart.c
index 91f1eb0058d7..5250bd7d390a 100644
--- a/drivers/tty/serial/owl-uart.c
+++ b/drivers/tty/serial/owl-uart.c
@@ -516,7 +516,7 @@ static const struct uart_ops owl_uart_ops = {
 
 #ifdef CONFIG_SERIAL_OWL_CONSOLE
 
-static void owl_console_putchar(struct uart_port *port, int ch)
+static void owl_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f0351e6f0ef6..affe71f8b50c 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1600,7 +1600,7 @@ static const struct uart_ops pch_uart_ops = {
 
 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
 
-static void pch_console_putchar(struct uart_port *port, int ch)
+static void pch_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct eg20t_port *priv =
 		container_of(port, struct eg20t_port, port);
diff --git a/drivers/tty/serial/pic32_uart.c b/drivers/tty/serial/pic32_uart.c
index 0a12fb11e698..b7a3a1b959b1 100644
--- a/drivers/tty/serial/pic32_uart.c
+++ b/drivers/tty/serial/pic32_uart.c
@@ -691,7 +691,7 @@ static const struct uart_ops pic32_uart_ops = {
 
 #ifdef CONFIG_SERIAL_PIC32_CONSOLE
 /* output given char */
-static void pic32_console_putchar(struct uart_port *port, int ch)
+static void pic32_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct pic32_sport *sport = to_pic32_sport(port);
 
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c
index 5359236b32d6..5d97c201ad88 100644
--- a/drivers/tty/serial/pmac_zilog.c
+++ b/drivers/tty/serial/pmac_zilog.c
@@ -1944,7 +1944,7 @@ static void __exit exit_pmz(void)
 
 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
 
-static void pmz_console_putchar(struct uart_port *port, int ch)
+static void pmz_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_pmac_port *uap =
 		container_of(port, struct uart_pmac_port, port);
diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c
index 30b099746a75..5d7b7e56661f 100644
--- a/drivers/tty/serial/pxa.c
+++ b/drivers/tty/serial/pxa.c
@@ -619,7 +619,7 @@ static void wait_for_xmitr(struct uart_pxa_port *up)
 	}
 }
 
-static void serial_pxa_console_putchar(struct uart_port *port, int ch)
+static void serial_pxa_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index aedc38893e6c..1543a6028856 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -397,7 +397,7 @@ static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
 #endif
 
 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
-static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch)
+static void qcom_geni_serial_wr_char(struct uart_port *uport, unsigned char ch)
 {
 	struct qcom_geni_private_data *private_data = uport->private_data;
 
diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c
index d550d8fa2fab..e5f1fded423a 100644
--- a/drivers/tty/serial/rda-uart.c
+++ b/drivers/tty/serial/rda-uart.c
@@ -573,7 +573,7 @@ static const struct uart_ops rda_uart_ops = {
 
 #ifdef CONFIG_SERIAL_RDA_CONSOLE
 
-static void rda_console_putchar(struct uart_port *port, int ch)
+static void rda_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
index 697b6a002a16..5fe6cccfc1ae 100644
--- a/drivers/tty/serial/sa1100.c
+++ b/drivers/tty/serial/sa1100.c
@@ -695,7 +695,7 @@ void __init sa1100_register_uart(int idx, int port)
 
 
 #ifdef CONFIG_SERIAL_SA1100_CONSOLE
-static void sa1100_console_putchar(struct uart_port *port, int ch)
+static void sa1100_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct sa1100_port *sport =
 		container_of(port, struct sa1100_port, port);
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index d002a4e48ed9..2bde7bde7116 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -2478,7 +2478,7 @@ static void s3c24xx_serial_put_poll_char(struct uart_port *port,
 #endif /* CONFIG_CONSOLE_POLL */
 
 static void
-s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
+s3c24xx_serial_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
 
@@ -2965,7 +2965,7 @@ static void samsung_early_busyuart_fifo(struct uart_port *port)
 		;
 }
 
-static void samsung_early_putc(struct uart_port *port, int c)
+static void samsung_early_putc(struct uart_port *port, unsigned char c)
 {
 	if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
 		samsung_early_busyuart_fifo(port);
diff --git a/drivers/tty/serial/sb1250-duart.c b/drivers/tty/serial/sb1250-duart.c
index 738df6d9c0d9..2cf8533ef760 100644
--- a/drivers/tty/serial/sb1250-duart.c
+++ b/drivers/tty/serial/sb1250-duart.c
@@ -820,7 +820,7 @@ static void __init sbd_probe_duarts(void)
  * console output.  The console_lock is held by the caller, so we
  * shouldn't be interrupted for more console activity.
  */
-static void sbd_console_putchar(struct uart_port *uport, int ch)
+static void sbd_console_putchar(struct uart_port *uport, unsigned char ch)
 {
 	struct sbd_port *sport = to_sport(uport);
 
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index 10cc16a71f26..c56de2e104d4 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -828,7 +828,7 @@ static const struct uart_ops sccnxp_ops = {
 };
 
 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
-static void sccnxp_console_putchar(struct uart_port *port, int c)
+static void sccnxp_console_putchar(struct uart_port *port, unsigned char c)
 {
 	int tryes = 100000;
 
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 846192a7b4bf..a1688a341411 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -1911,7 +1911,7 @@ static void uart_port_spin_lock_init(struct uart_port *port)
  */
 void uart_console_write(struct uart_port *port, const char *s,
 			unsigned int count,
-			void (*putchar)(struct uart_port *, int))
+			void (*putchar)(struct uart_port *, unsigned char))
 {
 	unsigned int i;
 
diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_txx9.c
index aaca4fe38486..b4d8c2733317 100644
--- a/drivers/tty/serial/serial_txx9.c
+++ b/drivers/tty/serial/serial_txx9.c
@@ -879,7 +879,7 @@ static void __init serial_txx9_register_ports(struct uart_driver *drv,
 
 #ifdef CONFIG_SERIAL_TXX9_CONSOLE
 
-static void serial_txx9_console_putchar(struct uart_port *port, int ch)
+static void serial_txx9_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_txx9_port *up = to_uart_txx9_port(port);
 
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index b610b27893a8..738093c7b255 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2957,7 +2957,7 @@ static void sci_cleanup_single(struct sci_port *port)
 
 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
-static void serial_console_putchar(struct uart_port *port, int ch)
+static void serial_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	sci_poll_put_char(port, ch);
 }
diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c
index b79900d0e91a..f5ac14c384c4 100644
--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -756,7 +756,7 @@ static void sifive_serial_poll_put_char(struct uart_port *port,
  */
 
 #ifdef CONFIG_SERIAL_EARLYCON
-static void early_sifive_serial_putc(struct uart_port *port, int c)
+static void early_sifive_serial_putc(struct uart_port *port, unsigned char c)
 {
 	while (__ssp_early_readl(port, SIFIVE_SERIAL_TXDATA_OFFS) &
 	       SIFIVE_SERIAL_TXDATA_FULL_MASK)
@@ -800,7 +800,7 @@ OF_EARLYCON_DECLARE(sifive, "sifive,fu540-c000-uart0",
 
 static struct sifive_serial_port *sifive_serial_console_ports[SIFIVE_SERIAL_MAX_PORTS];
 
-static void sifive_serial_console_putchar(struct uart_port *port, int ch)
+static void sifive_serial_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
 
diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index 9a7ae6384edf..4329b9c9cbf0 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -984,7 +984,7 @@ static void wait_for_xmitr(struct uart_port *port)
 	} while (status & SPRD_TX_FIFO_CNT_MASK);
 }
 
-static void sprd_console_putchar(struct uart_port *port, int ch)
+static void sprd_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	wait_for_xmitr(port);
 	serial_out(port, SPRD_TXD, ch);
@@ -1058,7 +1058,7 @@ console_initcall(sprd_serial_console_init);
 #define SPRD_CONSOLE	(&sprd_console)
 
 /* Support for earlycon */
-static void sprd_putc(struct uart_port *port, int c)
+static void sprd_putc(struct uart_port *port, unsigned char c)
 {
 	unsigned int timeout = SPRD_TIMEOUT;
 
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index 87e480cc8206..d7fd692286cf 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -854,7 +854,7 @@ static int asc_serial_resume(struct device *dev)
 /*----------------------------------------------------------------------*/
 
 #ifdef CONFIG_SERIAL_ST_ASC_CONSOLE
-static void asc_console_putchar(struct uart_port *port, int ch)
+static void asc_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	unsigned int timeout = 1000000;
 
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 1b3a611ac39e..87b5cd4c9743 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -1641,7 +1641,7 @@ static int stm32_usart_serial_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_SERIAL_STM32_CONSOLE
-static void stm32_usart_console_putchar(struct uart_port *port, int ch)
+static void stm32_usart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c
index 98b2f4fb9a99..c31389114b86 100644
--- a/drivers/tty/serial/sunsu.c
+++ b/drivers/tty/serial/sunsu.c
@@ -1281,7 +1281,7 @@ static void wait_for_xmitr(struct uart_sunsu_port *up)
 	}
 }
 
-static void sunsu_console_putchar(struct uart_port *port, int ch)
+static void sunsu_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct uart_sunsu_port *up =
 		container_of(port, struct uart_sunsu_port, port);
diff --git a/drivers/tty/serial/sunzilog.c b/drivers/tty/serial/sunzilog.c
index b714b00d2dad..c14275d83b0b 100644
--- a/drivers/tty/serial/sunzilog.c
+++ b/drivers/tty/serial/sunzilog.c
@@ -100,7 +100,7 @@ struct uart_sunzilog_port {
 #endif
 };
 
-static void sunzilog_putchar(struct uart_port *port, int ch);
+static void sunzilog_putchar(struct uart_port *port, unsigned char ch);
 
 #define ZILOG_CHANNEL_FROM_PORT(PORT)	((struct zilog_channel __iomem *)((PORT)->membase))
 #define UART_ZILOG(PORT)		((struct uart_sunzilog_port *)(PORT))
@@ -1125,7 +1125,7 @@ static void sunzilog_free_tables(void)
 
 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
 
-static void __maybe_unused sunzilog_putchar(struct uart_port *port, int ch)
+static void __maybe_unused sunzilog_putchar(struct uart_port *port, unsigned char ch)
 {
 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
 	int loops = ZS_PUT_CHAR_MAX_DELAY;
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index e1fa52d31474..007db67292a2 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -482,7 +482,7 @@ static void ulite_console_wait_tx(struct uart_port *port)
 			 "timeout waiting for TX buffer empty\n");
 }
 
-static void ulite_console_putchar(struct uart_port *port, int ch)
+static void ulite_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	ulite_console_wait_tx(port);
 	uart_out32(ch, ULITE_TX, port);
@@ -558,7 +558,7 @@ static struct console ulite_console = {
 	.data	= &ulite_uart_driver,
 };
 
-static void early_uartlite_putc(struct uart_port *port, int c)
+static void early_uartlite_putc(struct uart_port *port, unsigned char c)
 {
 	/*
 	 * Limit how many times we'll spin waiting for TX FIFO status.
diff --git a/drivers/tty/serial/vr41xx_siu.c b/drivers/tty/serial/vr41xx_siu.c
index 647198b1e2b9..6b303af5ee54 100644
--- a/drivers/tty/serial/vr41xx_siu.c
+++ b/drivers/tty/serial/vr41xx_siu.c
@@ -743,7 +743,7 @@ static void wait_for_xmitr(struct uart_port *port)
 	}
 }
 
-static void siu_console_putchar(struct uart_port *port, int ch)
+static void siu_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	wait_for_xmitr(port);
 	siu_write(port, UART_TX, ch);
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index 9adfe3dc970f..6f08136ce78a 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -484,7 +484,7 @@ static void wait_for_xmitr(struct uart_port *port)
 	} while (status & 0x10);
 }
 
-static void vt8500_console_putchar(struct uart_port *port, int c)
+static void vt8500_console_putchar(struct uart_port *port, unsigned char c)
 {
 	wait_for_xmitr(port);
 	writeb(c, port->membase + VT8500_TXFIFO);
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index d5e243908d9f..250a1d888eeb 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1142,7 +1142,7 @@ static struct uart_driver cdns_uart_uart_driver;
  * @port: Handle to the uart port structure
  * @ch: Character to be written
  */
-static void cdns_uart_console_putchar(struct uart_port *port, int ch)
+static void cdns_uart_console_putchar(struct uart_port *port, unsigned char ch)
 {
 	while (readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/zs.c b/drivers/tty/serial/zs.c
index 4b4f604646a7..70969bf9d82c 100644
--- a/drivers/tty/serial/zs.c
+++ b/drivers/tty/serial/zs.c
@@ -1124,7 +1124,7 @@ static int __init zs_probe_sccs(void)
 
 
 #ifdef CONFIG_SERIAL_ZS_CONSOLE
-static void zs_console_putchar(struct uart_port *uport, int ch)
+static void zs_console_putchar(struct uart_port *uport, unsigned char ch)
 {
 	struct zs_port *zport = to_zport(uport);
 	struct zs_scc *scc = zport->scc;
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 31f7fe527395..14ae35f68abb 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -399,7 +399,7 @@ int uart_set_options(struct uart_port *port, struct console *co, int baud,
 struct tty_driver *uart_console_device(struct console *co, int *index);
 void uart_console_write(struct uart_port *port, const char *s,
 			unsigned int count,
-			void (*putchar)(struct uart_port *, int));
+			void (*putchar)(struct uart_port *, unsigned char));
 
 /*
  * Port/driver registration/removal
