1/*
2 * BK Id: SCCS/s.ns16550.c 1.16 03/13/02 09:17:06 trini
3 */
4/*
5 * COM1 NS16550 support
6 */
7
8#include <linux/config.h>
9#include <linux/serialP.h>
10#include <linux/serial_reg.h>
11#include <asm/serial.h>
12
13#define SERIAL_BAUD	9600
14
15extern void outb(int port, unsigned char val);
16extern unsigned char inb(int port);
17extern unsigned long ISA_io;
18
19static struct serial_state rs_table[RS_TABLE_SIZE] = {
20	SERIAL_PORT_DFNS	/* Defined in <asm/serial.h> */
21};
22
23static int shift;
24
25unsigned long serial_init(int chan, void *ignored)
26{
27	unsigned long com_port;
28	unsigned char lcr, dlm;
29
30	/* We need to find out which type io we're expecting.  If it's
31	 * 'SERIAL_IO_PORT', we get an offset from the isa_io_base.
32	 * If it's 'SERIAL_IO_MEM', we can the exact location.  -- Tom */
33	switch (rs_table[chan].io_type) {
34		case SERIAL_IO_PORT:
35			com_port = rs_table[chan].port;
36			break;
37		case SERIAL_IO_MEM:
38			com_port = (unsigned long)rs_table[chan].iomem_base;
39			break;
40		default:
41			/* We can't deal with it. */
42			return -1;
43	}
44
45	/* How far apart the registers are. */
46	shift = rs_table[chan].iomem_reg_shift;
47
48	/* save the LCR */
49	lcr = inb(com_port + (UART_LCR << shift));
50	/* Access baud rate */
51	outb(com_port + (UART_LCR << shift), 0x80);
52	dlm = inb(com_port + (UART_DLM << shift));
53	/*
54	 * Test if serial port is unconfigured.
55	 * We assume that no-one uses less than 110 baud or
56	 * less than 7 bits per character these days.
57	 *  -- paulus.
58	 */
59
60	if ((dlm <= 4) && (lcr & 2))
61		/* port is configured, put the old LCR back */
62		outb(com_port + (UART_LCR << shift), lcr);
63	else {
64		/* Input clock. */
65		outb(com_port + (UART_DLL << shift),
66		     (BASE_BAUD / SERIAL_BAUD) & 0xFF);
67		outb(com_port + (UART_DLM << shift),
68		     (BASE_BAUD / SERIAL_BAUD) >> 8);
69		/* 8 data, 1 stop, no parity */
70		outb(com_port + (UART_LCR << shift), 0x03);
71		/* RTS/DTR */
72		outb(com_port + (UART_MCR << shift), 0x03);
73	}
74	/* Clear & enable FIFOs */
75	outb(com_port + (UART_FCR << shift), 0x07);
76
77	return (com_port);
78}
79
80void
81serial_putc(unsigned long com_port, unsigned char c)
82{
83	while ((inb(com_port + (UART_LSR << shift)) & UART_LSR_THRE) == 0)
84		;
85	outb(com_port, c);
86}
87
88unsigned char
89serial_getc(unsigned long com_port)
90{
91	while ((inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) == 0)
92		;
93	return inb(com_port);
94}
95
96int
97serial_tstc(unsigned long com_port)
98{
99	return ((inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) != 0);
100}
101
102void
103serial_close(unsigned long com_port)
104{
105}
106