/* * (C) Copyright 2003 * Martin Krause, TQ-Systems GmbH, <martin.krause@tqs.de> * * Based on cpu/arm920t/serial.c, by Gary Jennejohn * (C) Copyright 2002 Gary Jennejohn, DENX Software Engineering, <gj@denx.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA * */#include <common.h>#include <s3c2400.h>#include "rs485.h"static void rs485_setbrg (void);static void rs485_cfgio (void);static void set_rs485re(unsigned char rs485re_state);static void set_rs485de(unsigned char rs485de_state);static void rs485_setbrg (void);#ifdef	NOT_USEDstatic void trab_rs485_disable_tx(void);static void trab_rs485_disable_rx(void);#endif#define UART_NR	S3C24X0_UART1/* CPLD-Register for controlling TRAB hardware functions */#define CPLD_RS485_RE           ((volatile unsigned long *)0x04028000)static void rs485_setbrg (void){	S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR);	int i;	unsigned int reg = 0;	/* value is calculated so : (int)(PCLK/16./baudrate) -1 */	/* reg = (33000000 / (16 * gd->baudrate)) - 1; */	reg = (33000000 / (16 * 38400)) - 1;	/* FIFO enable, Tx/Rx FIFO clear */	uart->UFCON = 0x07;	uart->UMCON = 0x0;	/* Normal,No parity,1 stop,8 bit */	uart->ULCON = 0x3;	/*	 * tx=level,rx=edge,disable timeout int.,enable rx error int.,	 * normal,interrupt or polling	 */	uart->UCON = 0x245;	uart->UBRDIV = reg;	for (i = 0; i < 100; i++);}static void rs485_cfgio (void){	S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();	gpio->PFCON &= ~(0x3 << 2);	gpio->PFCON |=  (0x2 << 2); /* configure GPF1 as RXD1 */	gpio->PFCON &= ~(0x3 << 6);	gpio->PFCON |=  (0x2 << 6); /* configure GPF3 as TXD1 */	gpio->PFUP |= (1 << 1); /* disable pullup on GPF1 */	gpio->PFUP |= (1 << 3); /* disable pullup on GPF3 */	gpio->PACON &= ~(1 << 11); /* set GPA11 (RS485_DE) to output */}/* * Initialise the rs485 port with the given baudrate. The settings * are always 8 data bits, no parity, 1 stop bit, no start bits. * */int rs485_init (void){	rs485_cfgio ();	rs485_setbrg ();	return (0);}/* * Read a single byte from the rs485 port. Returns 1 on success, 0 * otherwise. When the function is succesfull, the character read is * written into its argument c. */int rs485_getc (void){	S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR);	/* wait for character to arrive */	while (!(uart->UTRSTAT & 0x1));	return uart->URXH & 0xff;}/* * Output a single byte to the rs485 port. */void rs485_putc (const char c){	S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR);	/* wait for room in the tx FIFO */	while (!(uart->UTRSTAT & 0x2));	uart->UTXH = c;	/* If \n, also do \r */	if (c == '\n')		rs485_putc ('\r');}/* * Test whether a character is in the RX buffer */int rs485_tstc (void){	S3C24X0_UART * const uart = S3C24X0_GetBase_UART(UART_NR);	return uart->UTRSTAT & 0x1;}void rs485_puts (const char *s){	while (*s) {		rs485_putc (*s++);	}}/* * State table: *	RE	DE	Result *	1	1	XMIT *	0	0	RCV *	1	0	Shutdown *//* function that controls the receiver enable for the rs485 *//* rs485re_state reflects the level (0/1) of the RE pin */static void set_rs485re(unsigned char rs485re_state){	if(rs485re_state)		*CPLD_RS485_RE = 0x010000;	else		*CPLD_RS485_RE = 0x0;}/* function that controls the sender enable for the rs485 *//* rs485de_state reflects the level (0/1) of the DE pin */static void set_rs485de(unsigned char rs485de_state){	S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();	/* This is on PORT A bit 11 */	if(rs485de_state)		gpio->PADAT |= (1 << 11);	else		gpio->PADAT &= ~(1 << 11);}void trab_rs485_enable_tx(void){	set_rs485de(1);	set_rs485re(1);}void trab_rs485_enable_rx(void){	set_rs485re(0);	set_rs485de(0);}#ifdef	NOT_USEDstatic void trab_rs485_disable_tx(void){	set_rs485de(0);}static void trab_rs485_disable_rx(void){	set_rs485re(1);}#endif