1 /*
2  * altera-lpt.c
3  *
4  * altera FPGA driver
5  *
6  * Copyright (C) Altera Corporation 1998-2001
7  * Copyright (C) 2010 NetUP Inc.
8  * Copyright (C) 2010 Abylay Ospan <aospan@netup.ru>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 #include <linux/io.h>
27 #include <linux/kernel.h>
28 #include "altera-exprt.h"
29 
30 static int lpt_hardware_initialized;
31 
32 static void byteblaster_write(int port, int data)
33 {
34 	outb((u8)data, (u16)(port + 0x378));
35 };
36 
37 static int byteblaster_read(int port)
38 {
39 	int data = 0;
40 	data = inb((u16)(port + 0x378));
41 	return data & 0xff;
42 };
43 
44 int netup_jtag_io_lpt(void *device, int tms, int tdi, int read_tdo)
45 {
46 	int data = 0;
47 	int tdo = 0;
48 	int initial_lpt_ctrl = 0;
49 
50 	if (!lpt_hardware_initialized) {
51 		initial_lpt_ctrl = byteblaster_read(2);
52 		byteblaster_write(2, (initial_lpt_ctrl | 0x02) & 0xdf);
53 		lpt_hardware_initialized = 1;
54 	}
55 
56 	data = ((tdi ? 0x40 : 0) | (tms ? 0x02 : 0));
57 
58 	byteblaster_write(0, data);
59 
60 	if (read_tdo) {
61 		tdo = byteblaster_read(1);
62 		tdo = ((tdo & 0x80) ? 0 : 1);
63 	}
64 
65 	byteblaster_write(0, data | 0x01);
66 
67 	byteblaster_write(0, data);
68 
69 	return tdo;
70 }
71