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
byteblaster_write(int port,int data)32 static void byteblaster_write(int port, int data)
33 {
34 outb((u8)data, (u16)(port + 0x378));
35 };
36
byteblaster_read(int port)37 static int byteblaster_read(int port)
38 {
39 int data = 0;
40 data = inb((u16)(port + 0x378));
41 return data & 0xff;
42 };
43
netup_jtag_io_lpt(void * device,int tms,int tdi,int read_tdo)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