/* serial.h - serial device interface */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2000,2001,2002  Free Software Foundation, Inc.
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef GRUB_SERIAL_HEADER
#define GRUB_SERIAL_HEADER      1

/* Macros.  */

/* The maximum number of ports we ever try to use. */
#define SERIAL_MAX_PORTS        4

/* The offsets of UART registers.  */
#define UART_TX         0
#define UART_RX         0
#define UART_DLL        0
#define UART_IER        1
#define UART_DLH        1
#define UART_IIR        2
#define UART_FCR        2
#define UART_LCR        3
#define UART_MCR        4
#define UART_LSR        5
#define UART_MSR        6
#define UART_SR         7

/* For LSR bits.  */
#define UART_DATA_READY         0x01
#define UART_EMPTY_TRANSMITTER  0x20

/* The type of parity.  */
#define UART_NO_PARITY          0x00
#define UART_ODD_PARITY         0x08
#define UART_EVEN_PARITY        0x18

/* The type of word length.  */
#define UART_5BITS_WORD 0x00
#define UART_6BITS_WORD 0x01
#define UART_7BITS_WORD 0x02
#define UART_8BITS_WORD 0x03

/* The type of the length of stop bit.  */
#define UART_1_STOP_BIT         0x00
#define UART_2_STOP_BITS        0x04

/* the switch of DLAB.  */
#define UART_DLAB       0x80

/* Enable the FIFO.  */
#define UART_ENABLE_FIFO        0xC7

/* Turn on DTR, RTS, and OUT2.  */
#define UART_ENABLE_MODEM       0x0B

/* Arbitrary pattern to write during existence testing. */
#define UART_SR_TEST    0x4F


/* Function prototypes.  */

/* Fetch a key.  */
int serial_hw_fetch (void);

/* Put a character.  */
void serial_hw_put (int c);

/* Insert a delay.  */
void serial_hw_delay (void);

/* Return the port number for the UNITth serial device.  */
unsigned short serial_hw_get_port (int unit);

/* Initialize a serial device.  */
int serial_hw_init (unsigned short port, unsigned int speed,
                    int word_len, int parity, int stop_bit_len);

#ifdef GRUB_UTIL
/* Set the file name of a serial device (or a pty device). This is a
   function specific to the grub shell.  */
void serial_set_device (const char *device);
#endif /* GRUB_UTIL */

#endif /* ! GRUB_SERIAL_HEADER */