1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   *  Copyright (c) 1998-2001 Vojtech Pavlik
4   */
5  
6  /*
7   * PDPI Lightning 4 gamecard driver for Linux.
8   */
9  
10  #include <asm/io.h>
11  #include <linux/delay.h>
12  #include <linux/errno.h>
13  #include <linux/ioport.h>
14  #include <linux/kernel.h>
15  #include <linux/module.h>
16  #include <linux/init.h>
17  #include <linux/gameport.h>
18  
19  #define L4_PORT			0x201
20  #define L4_SELECT_ANALOG	0xa4
21  #define L4_SELECT_DIGITAL	0xa5
22  #define L4_SELECT_SECONDARY	0xa6
23  #define L4_CMD_ID		0x80
24  #define L4_CMD_GETCAL		0x92
25  #define L4_CMD_SETCAL		0x93
26  #define L4_ID			0x04
27  #define L4_BUSY			0x01
28  #define L4_TIMEOUT		80	/* 80 us */
29  
30  MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
31  MODULE_DESCRIPTION("PDPI Lightning 4 gamecard driver");
32  MODULE_LICENSE("GPL");
33  
34  struct l4 {
35  	struct gameport *gameport;
36  	unsigned char port;
37  };
38  
39  static struct l4 l4_ports[8];
40  
41  /*
42   * l4_wait_ready() waits for the L4 to become ready.
43   */
44  
l4_wait_ready(void)45  static int l4_wait_ready(void)
46  {
47  	unsigned int t = L4_TIMEOUT;
48  
49  	while ((inb(L4_PORT) & L4_BUSY) && t > 0) t--;
50  	return -(t <= 0);
51  }
52  
53  /*
54   * l4_cooked_read() reads data from the Lightning 4.
55   */
56  
l4_cooked_read(struct gameport * gameport,int * axes,int * buttons)57  static int l4_cooked_read(struct gameport *gameport, int *axes, int *buttons)
58  {
59  	struct l4 *l4 = gameport->port_data;
60  	unsigned char status;
61  	int i, result = -1;
62  
63  	outb(L4_SELECT_ANALOG, L4_PORT);
64  	outb(L4_SELECT_DIGITAL + (l4->port >> 2), L4_PORT);
65  
66  	if (inb(L4_PORT) & L4_BUSY) goto fail;
67  	outb(l4->port & 3, L4_PORT);
68  
69  	if (l4_wait_ready()) goto fail;
70  	status = inb(L4_PORT);
71  
72  	for (i = 0; i < 4; i++)
73  		if (status & (1 << i)) {
74  			if (l4_wait_ready()) goto fail;
75  			axes[i] = inb(L4_PORT);
76  			if (axes[i] > 252) axes[i] = -1;
77  		}
78  
79  	if (status & 0x10) {
80  		if (l4_wait_ready()) goto fail;
81  		*buttons = inb(L4_PORT) & 0x0f;
82  	}
83  
84  	result = 0;
85  
86  fail:	outb(L4_SELECT_ANALOG, L4_PORT);
87  	return result;
88  }
89  
l4_open(struct gameport * gameport,int mode)90  static int l4_open(struct gameport *gameport, int mode)
91  {
92  	struct l4 *l4 = gameport->port_data;
93  
94          if (l4->port != 0 && mode != GAMEPORT_MODE_COOKED)
95  		return -1;
96  	outb(L4_SELECT_ANALOG, L4_PORT);
97  	return 0;
98  }
99  
100  /*
101   * l4_getcal() reads the L4 with calibration values.
102   */
103  
l4_getcal(int port,int * cal)104  static int l4_getcal(int port, int *cal)
105  {
106  	int i, result = -1;
107  
108  	outb(L4_SELECT_ANALOG, L4_PORT);
109  	outb(L4_SELECT_DIGITAL + (port >> 2), L4_PORT);
110  	if (inb(L4_PORT) & L4_BUSY)
111  		goto out;
112  
113  	outb(L4_CMD_GETCAL, L4_PORT);
114  	if (l4_wait_ready())
115  		goto out;
116  
117  	if (inb(L4_PORT) != L4_SELECT_DIGITAL + (port >> 2))
118  		goto out;
119  
120  	if (l4_wait_ready())
121  		goto out;
122          outb(port & 3, L4_PORT);
123  
124  	for (i = 0; i < 4; i++) {
125  		if (l4_wait_ready())
126  			goto out;
127  		cal[i] = inb(L4_PORT);
128  	}
129  
130  	result = 0;
131  
132  out:	outb(L4_SELECT_ANALOG, L4_PORT);
133  	return result;
134  }
135  
136  /*
137   * l4_setcal() programs the L4 with calibration values.
138   */
139  
l4_setcal(int port,int * cal)140  static int l4_setcal(int port, int *cal)
141  {
142  	int i, result = -1;
143  
144  	outb(L4_SELECT_ANALOG, L4_PORT);
145  	outb(L4_SELECT_DIGITAL + (port >> 2), L4_PORT);
146  	if (inb(L4_PORT) & L4_BUSY)
147  		goto out;
148  
149  	outb(L4_CMD_SETCAL, L4_PORT);
150  	if (l4_wait_ready())
151  		goto out;
152  
153  	if (inb(L4_PORT) != L4_SELECT_DIGITAL + (port >> 2))
154  		goto out;
155  
156  	if (l4_wait_ready())
157  		goto out;
158          outb(port & 3, L4_PORT);
159  
160  	for (i = 0; i < 4; i++) {
161  		if (l4_wait_ready())
162  			goto out;
163  		outb(cal[i], L4_PORT);
164  	}
165  
166  	result = 0;
167  
168  out:	outb(L4_SELECT_ANALOG, L4_PORT);
169  	return result;
170  }
171  
172  /*
173   * l4_calibrate() calibrates the L4 for the attached device, so
174   * that the device's resistance fits into the L4's 8-bit range.
175   */
176  
l4_calibrate(struct gameport * gameport,int * axes,int * max)177  static int l4_calibrate(struct gameport *gameport, int *axes, int *max)
178  {
179  	int i, t;
180  	int cal[4];
181  	struct l4 *l4 = gameport->port_data;
182  
183  	if (l4_getcal(l4->port, cal))
184  		return -1;
185  
186  	for (i = 0; i < 4; i++) {
187  		t = (max[i] * cal[i]) / 200;
188  		t = (t < 1) ? 1 : ((t > 255) ? 255 : t);
189  		axes[i] = (axes[i] < 0) ? -1 : (axes[i] * cal[i]) / t;
190  		axes[i] = (axes[i] > 252) ? 252 : axes[i];
191  		cal[i] = t;
192  	}
193  
194  	if (l4_setcal(l4->port, cal))
195  		return -1;
196  
197  	return 0;
198  }
199  
l4_create_ports(int card_no)200  static int __init l4_create_ports(int card_no)
201  {
202  	struct l4 *l4;
203  	struct gameport *port;
204  	int i, idx;
205  
206  	for (i = 0; i < 4; i++) {
207  
208  		idx = card_no * 4 + i;
209  		l4 = &l4_ports[idx];
210  
211  		if (!(l4->gameport = port = gameport_allocate_port())) {
212  			printk(KERN_ERR "lightning: Memory allocation failed\n");
213  			while (--i >= 0) {
214  				gameport_free_port(l4->gameport);
215  				l4->gameport = NULL;
216  			}
217  			return -ENOMEM;
218  		}
219  		l4->port = idx;
220  
221  		port->port_data = l4;
222  		port->open = l4_open;
223  		port->cooked_read = l4_cooked_read;
224  		port->calibrate = l4_calibrate;
225  
226  		gameport_set_name(port, "PDPI Lightning 4");
227  		gameport_set_phys(port, "isa%04x/gameport%d", L4_PORT, idx);
228  
229  		if (idx == 0)
230  			port->io = L4_PORT;
231  	}
232  
233  	return 0;
234  }
235  
l4_add_card(int card_no)236  static int __init l4_add_card(int card_no)
237  {
238  	int cal[4] = { 255, 255, 255, 255 };
239  	int i, rev, result;
240  	struct l4 *l4;
241  
242  	outb(L4_SELECT_ANALOG, L4_PORT);
243  	outb(L4_SELECT_DIGITAL + card_no, L4_PORT);
244  
245  	if (inb(L4_PORT) & L4_BUSY)
246  		return -1;
247  	outb(L4_CMD_ID, L4_PORT);
248  
249  	if (l4_wait_ready())
250  		return -1;
251  
252  	if (inb(L4_PORT) != L4_SELECT_DIGITAL + card_no)
253  		return -1;
254  
255  	if (l4_wait_ready())
256  		return -1;
257  	if (inb(L4_PORT) != L4_ID)
258  		return -1;
259  
260  	if (l4_wait_ready())
261  		return -1;
262  	rev = inb(L4_PORT);
263  
264  	if (!rev)
265  		return -1;
266  
267  	result = l4_create_ports(card_no);
268  	if (result)
269  		return result;
270  
271  	printk(KERN_INFO "gameport: PDPI Lightning 4 %s card v%d.%d at %#x\n",
272  		card_no ? "secondary" : "primary", rev >> 4, rev, L4_PORT);
273  
274  	for (i = 0; i < 4; i++) {
275  		l4 = &l4_ports[card_no * 4 + i];
276  
277  		if (rev > 0x28)		/* on 2.9+ the setcal command works correctly */
278  			l4_setcal(l4->port, cal);
279  		gameport_register_port(l4->gameport);
280  	}
281  
282  	return 0;
283  }
284  
l4_init(void)285  static int __init l4_init(void)
286  {
287  	int i, cards = 0;
288  
289  	if (!request_region(L4_PORT, 1, "lightning"))
290  		return -EBUSY;
291  
292  	for (i = 0; i < 2; i++)
293  		if (l4_add_card(i) == 0)
294  			cards++;
295  
296  	outb(L4_SELECT_ANALOG, L4_PORT);
297  
298  	if (!cards) {
299  		release_region(L4_PORT, 1);
300  		return -ENODEV;
301  	}
302  
303  	return 0;
304  }
305  
l4_exit(void)306  static void __exit l4_exit(void)
307  {
308  	int i;
309  	int cal[4] = { 59, 59, 59, 59 };
310  
311  	for (i = 0; i < 8; i++)
312  		if (l4_ports[i].gameport) {
313  			l4_setcal(l4_ports[i].port, cal);
314  			gameport_unregister_port(l4_ports[i].gameport);
315  		}
316  
317  	outb(L4_SELECT_ANALOG, L4_PORT);
318  	release_region(L4_PORT, 1);
319  }
320  
321  module_init(l4_init);
322  module_exit(l4_exit);
323