Commit d358788f authored by Russell King's avatar Russell King Committed by Russell King
Browse files

[SERIAL] kernel console should send CRLF not LFCR 



Glen Turner reported that writing LFCR rather than the more
traditional CRLF causes issues with some terminals.

Since this aflicts many serial drivers, extract the common code
to a library function (uart_console_write) and arrange for each
driver to supply a "putchar" function.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 7705a879

drivers/serial/21285.c

+7 −12
Original line number Diff line number Diff line
@@ -375,23 +375,18 @@ static void serial21285_setup_ports(void) 
}



#ifdef CONFIG_SERIAL_21285_CONSOLE

static void serial21285_console_putchar(struct uart_port *port, int ch)

{

	while (*CSR_UARTFLG & 0x20)

		barrier();

	*CSR_UARTDR = ch;

}



static void

serial21285_console_write(struct console *co, const char *s,

			  unsigned int count)

{

	int i;



	for (i = 0; i < count; i++) {

		while (*CSR_UARTFLG & 0x20)

			barrier();

		*CSR_UARTDR = s[i];

		if (s[i] == '\n') {

			while (*CSR_UARTFLG & 0x20)

				barrier();

			*CSR_UARTDR = '\r';

		}

	}

	uart_console_write(&serial21285_port, s, count, serial21285_console_putchar);

}



static void __init

drivers/serial/8250.c

+9 −17
Original line number Diff line number Diff line
@@ -2182,6 +2182,14 @@ static inline void wait_for_xmitr(struct uart_8250_port *up, int bits) 
	}

}



static void serial8250_console_putchar(struct uart_port *port, int ch)

{

	struct uart_8250_port *up = (struct uart_8250_port *)port;



	wait_for_xmitr(up, UART_LSR_THRE);

	serial_out(up, UART_TX, ch);

}



/*

 *	Print a string to the serial port trying not to disturb

 *	any possible real use of the port...
@@ -2193,7 +2201,6 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) 
{

	struct uart_8250_port *up = &serial8250_ports[co->index];

	unsigned int ier;

	int i;



	touch_nmi_watchdog();
@@ -2207,22 +2214,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) 
	else

		serial_out(up, UART_IER, 0);



	/*

	 *	Now, do each character

	 */

	for (i = 0; i < count; i++, s++) {

		wait_for_xmitr(up, UART_LSR_THRE);



		/*

		 *	Send the character out.

		 *	If a LF, also do CR...

		 */

		serial_out(up, UART_TX, *s);

		if (*s == 10) {

			wait_for_xmitr(up, UART_LSR_THRE);

			serial_out(up, UART_TX, 13);

		}

	}

	uart_console_write(&up->port, s, count, serial8250_console_putchar);



	/*

	 *	Finally, wait for transmitter to become empty

drivers/serial/8250_early.c

+2 −7
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ static void __init wait_for_xmitr(struct uart_port *port) 
	}

}



static void __init putc(struct uart_port *port, unsigned char c)

static void __init putc(struct uart_port *port, int c)

{

	wait_for_xmitr(port);

	serial_out(port, UART_TX, c);
@@ -89,12 +89,7 @@ static void __init early_uart_write(struct console *console, const char *s, unsi 
	ier = serial_in(port, UART_IER);

	serial_out(port, UART_IER, 0);



	while (*s && count-- > 0) {

		putc(port, *s);

		if (*s == '\n')

			putc(port, '\r');

		s++;

	}

	uart_console_write(port, s, count, putc);



	/* Wait for transmitter to become empty and restore the IER */

	wait_for_xmitr(port);

drivers/serial/amba-pl010.c

+8 −16
Original line number Diff line number Diff line
@@ -591,12 +591,18 @@ 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)

{

	while (!UART_TX_READY(UART_GET_FR(port)))

		barrier();

	UART_PUT_CHAR(port, ch);

}



static void

pl010_console_write(struct console *co, const char *s, unsigned int count)

{

	struct uart_port *port = &amba_ports[co->index].port;

	unsigned int status, old_cr;

	int i;



	/*

	 *	First save the CR then disable the interrupts
@@ -604,21 +610,7 @@ pl010_console_write(struct console *co, const char *s, unsigned int count) 
	old_cr = UART_GET_CR(port);

	UART_PUT_CR(port, UART01x_CR_UARTEN);



	/*

	 *	Now, do each character

	 */

	for (i = 0; i < count; i++) {

		do {

			status = UART_GET_FR(port);

		} while (!UART_TX_READY(status));

		UART_PUT_CHAR(port, s[i]);

		if (s[i] == '\n') {

			do {

				status = UART_GET_FR(port);

			} while (!UART_TX_READY(status));

			UART_PUT_CHAR(port, '\r');

		}

	}

	uart_console_write(port, s, count, pl010_console_putchar);



	/*

	 *	Finally, wait for transmitter to become empty

drivers/serial/amba-pl011.c

+5 −15
Original line number Diff line number Diff line
@@ -587,14 +587,12 @@ static struct uart_amba_port *amba_ports[UART_NR]; 


#ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE



static inline void

pl011_console_write_char(struct uart_amba_port *uap, char ch)

static void pl011_console_putchar(struct uart_port *port, int ch)

{

	unsigned int status;

	struct uart_amba_port *uap = (struct uart_amba_port *)port;



	do {

		status = readw(uap->port.membase + UART01x_FR);

	} while (status & UART01x_FR_TXFF);

	while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)

		barrier();

	writew(ch, uap->port.membase + UART01x_DR);

}
@@ -603,7 +601,6 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) 
{

	struct uart_amba_port *uap = amba_ports[co->index];

	unsigned int status, old_cr, new_cr;

	int i;



	clk_enable(uap->clk);
@@ -615,14 +612,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) 
	new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;

	writew(new_cr, uap->port.membase + UART011_CR);



	/*

	 *	Now, do each character

	 */

	for (i = 0; i < count; i++) {

		pl011_console_write_char(uap, s[i]);

		if (s[i] == '\n')

			pl011_console_write_char(uap, '\r');

	}

	uart_console_write(&uap->port, s, count, pl011_console_putchar);



	/*

	 *	Finally, wait for transmitter to become empty