1 /*
2  *  Copyright (c) 1998-2005 Vojtech Pavlik
3  */
4 
5 /*
6  * Microsoft SideWinder joystick family driver for Linux
7  */
8 
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  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  * Should you need to contact me, the author, you can do so either by
25  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
26  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
27  */
28 
29 #include <linux/delay.h>
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/slab.h>
33 #include <linux/init.h>
34 #include <linux/input.h>
35 #include <linux/gameport.h>
36 #include <linux/jiffies.h>
37 
38 #define DRIVER_DESC	"Microsoft SideWinder joystick family driver"
39 
40 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
41 MODULE_DESCRIPTION(DRIVER_DESC);
42 MODULE_LICENSE("GPL");
43 
44 /*
45  * These are really magic values. Changing them can make a problem go away,
46  * as well as break everything.
47  */
48 
49 #undef SW_DEBUG
50 #undef SW_DEBUG_DATA
51 
52 #define SW_START	600	/* The time we wait for the first bit [600 us] */
53 #define SW_STROBE	60	/* Max time per bit [60 us] */
54 #define SW_TIMEOUT	6	/* Wait for everything to settle [6 ms] */
55 #define SW_KICK		45	/* Wait after A0 fall till kick [45 us] */
56 #define SW_END		8	/* Number of bits before end of packet to kick */
57 #define SW_FAIL		16	/* Number of packet read errors to fail and reinitialize */
58 #define SW_BAD		2	/* Number of packet read errors to switch off 3d Pro optimization */
59 #define SW_OK		64	/* Number of packet read successes to switch optimization back on */
60 #define SW_LENGTH	512	/* Max number of bits in a packet */
61 
62 #ifdef SW_DEBUG
63 #define dbg(format, arg...) printk(KERN_DEBUG __FILE__ ": " format "\n" , ## arg)
64 #else
65 #define dbg(format, arg...) do {} while (0)
66 #endif
67 
68 /*
69  * SideWinder joystick types ...
70  */
71 
72 #define SW_ID_3DP	0
73 #define SW_ID_GP	1
74 #define SW_ID_PP	2
75 #define SW_ID_FFP	3
76 #define SW_ID_FSP	4
77 #define SW_ID_FFW	5
78 
79 /*
80  * Names, buttons, axes ...
81  */
82 
83 static char *sw_name[] = {	"3D Pro", "GamePad", "Precision Pro", "Force Feedback Pro", "FreeStyle Pro",
84 				"Force Feedback Wheel" };
85 
86 static char sw_abs[][7] = {
87 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
88 	{ ABS_X, ABS_Y },
89 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
90 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
91 	{ ABS_X, ABS_Y,         ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
92 	{ ABS_RX, ABS_RUDDER,   ABS_THROTTLE }};
93 
94 static char sw_bit[][7] = {
95 	{ 10, 10,  9, 10,  1,  1 },
96 	{  1,  1                 },
97 	{ 10, 10,  6,  7,  1,  1 },
98 	{ 10, 10,  6,  7,  1,  1 },
99 	{ 10, 10,  6,  1,  1     },
100 	{ 10,  7,  7,  1,  1     }};
101 
102 static short sw_btn[][12] = {
103 	{ BTN_TRIGGER, BTN_TOP, BTN_THUMB, BTN_THUMB2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_MODE },
104 	{ BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, BTN_TL, BTN_TR, BTN_START, BTN_MODE },
105 	{ BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_SELECT },
106 	{ BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_SELECT },
107 	{ BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, BTN_TL, BTN_TR, BTN_START, BTN_MODE, BTN_SELECT },
108 	{ BTN_TRIGGER, BTN_TOP, BTN_THUMB, BTN_THUMB2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4 }};
109 
110 static struct {
111 	int x;
112 	int y;
113 } sw_hat_to_axis[] = {{ 0, 0}, { 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}};
114 
115 struct sw {
116 	struct gameport *gameport;
117 	struct input_dev *dev[4];
118 	char name[64];
119 	char phys[4][32];
120 	int length;
121 	int type;
122 	int bits;
123 	int number;
124 	int fail;
125 	int ok;
126 	int reads;
127 	int bads;
128 };
129 
130 /*
131  * sw_read_packet() is a function which reads either a data packet, or an
132  * identification packet from a SideWinder joystick. The protocol is very,
133  * very, very braindamaged. Microsoft patented it in US patent #5628686.
134  */
135 
136 static int sw_read_packet(struct gameport *gameport, unsigned char *buf, int length, int id)
137 {
138 	unsigned long flags;
139 	int timeout, bitout, sched, i, kick, start, strobe;
140 	unsigned char pending, u, v;
141 
142 	i = -id;						/* Don't care about data, only want ID */
143 	timeout = id ? gameport_time(gameport, SW_TIMEOUT * 1000) : 0; /* Set up global timeout for ID packet */
144 	kick = id ? gameport_time(gameport, SW_KICK) : 0;	/* Set up kick timeout for ID packet */
145 	start = gameport_time(gameport, SW_START);
146 	strobe = gameport_time(gameport, SW_STROBE);
147 	bitout = start;
148 	pending = 0;
149 	sched = 0;
150 
151         local_irq_save(flags);					/* Quiet, please */
152 
153 	gameport_trigger(gameport);				/* Trigger */
154 	v = gameport_read(gameport);
155 
156 	do {
157 		bitout--;
158 		u = v;
159 		v = gameport_read(gameport);
160 	} while (!(~v & u & 0x10) && (bitout > 0));		/* Wait for first falling edge on clock */
161 
162 	if (bitout > 0)
163 		bitout = strobe;				/* Extend time if not timed out */
164 
165 	while ((timeout > 0 || bitout > 0) && (i < length)) {
166 
167 		timeout--;
168 		bitout--;					/* Decrement timers */
169 		sched--;
170 
171 		u = v;
172 		v = gameport_read(gameport);
173 
174 		if ((~u & v & 0x10) && (bitout > 0)) {		/* Rising edge on clock - data bit */
175 			if (i >= 0)				/* Want this data */
176 				buf[i] = v >> 5;		/* Store it */
177 			i++;					/* Advance index */
178 			bitout = strobe;			/* Extend timeout for next bit */
179 		}
180 
181 		if (kick && (~v & u & 0x01)) {			/* Falling edge on axis 0 */
182 			sched = kick;				/* Schedule second trigger */
183 			kick = 0;				/* Don't schedule next time on falling edge */
184 			pending = 1;				/* Mark schedule */
185 		}
186 
187 		if (pending && sched < 0 && (i > -SW_END)) {	/* Second trigger time */
188 			gameport_trigger(gameport);		/* Trigger */
189 			bitout = start;				/* Long bit timeout */
190 			pending = 0;				/* Unmark schedule */
191 			timeout = 0;				/* Switch from global to bit timeouts */
192 		}
193 	}
194 
195 	local_irq_restore(flags);					/* Done - relax */
196 
197 #ifdef SW_DEBUG_DATA
198 	{
199 		int j;
200 		printk(KERN_DEBUG "sidewinder.c: Read %d triplets. [", i);
201 		for (j = 0; j < i; j++) printk("%d", buf[j]);
202 		printk("]\n");
203 	}
204 #endif
205 
206 	return i;
207 }
208 
209 /*
210  * sw_get_bits() and GB() compose bits from the triplet buffer into a __u64.
211  * Parameter 'pos' is bit number inside packet where to start at, 'num' is number
212  * of bits to be read, 'shift' is offset in the resulting __u64 to start at, bits
213  * is number of bits per triplet.
214  */
215 
216 #define GB(pos,num) sw_get_bits(buf, pos, num, sw->bits)
217 
218 static __u64 sw_get_bits(unsigned char *buf, int pos, int num, char bits)
219 {
220 	__u64 data = 0;
221 	int tri = pos % bits;						/* Start position */
222 	int i   = pos / bits;
223 	int bit = 0;
224 
225 	while (num--) {
226 		data |= (__u64)((buf[i] >> tri++) & 1) << bit++;	/* Transfer bit */
227 		if (tri == bits) {
228 			i++;						/* Next triplet */
229 			tri = 0;
230 		}
231 	}
232 
233 	return data;
234 }
235 
236 /*
237  * sw_init_digital() initializes a SideWinder 3D Pro joystick
238  * into digital mode.
239  */
240 
241 static void sw_init_digital(struct gameport *gameport)
242 {
243 	int seq[] = { 140, 140+725, 140+300, 0 };
244 	unsigned long flags;
245 	int i, t;
246 
247         local_irq_save(flags);
248 
249 	i = 0;
250         do {
251                 gameport_trigger(gameport);			/* Trigger */
252 		t = gameport_time(gameport, SW_TIMEOUT * 1000);
253 		while ((gameport_read(gameport) & 1) && t) t--;	/* Wait for axis to fall back to 0 */
254                 udelay(seq[i]);					/* Delay magic time */
255         } while (seq[++i]);
256 
257 	gameport_trigger(gameport);				/* Last trigger */
258 
259 	local_irq_restore(flags);
260 }
261 
262 /*
263  * sw_parity() computes parity of __u64
264  */
265 
266 static int sw_parity(__u64 t)
267 {
268 	int x = t ^ (t >> 32);
269 
270 	x ^= x >> 16;
271 	x ^= x >> 8;
272 	x ^= x >> 4;
273 	x ^= x >> 2;
274 	x ^= x >> 1;
275 	return x & 1;
276 }
277 
278 /*
279  * sw_ccheck() checks synchronization bits and computes checksum of nibbles.
280  */
281 
282 static int sw_check(__u64 t)
283 {
284 	unsigned char sum = 0;
285 
286 	if ((t & 0x8080808080808080ULL) ^ 0x80)			/* Sync */
287 		return -1;
288 
289 	while (t) {						/* Sum */
290 		sum += t & 0xf;
291 		t >>= 4;
292 	}
293 
294 	return sum & 0xf;
295 }
296 
297 /*
298  * sw_parse() analyzes SideWinder joystick data, and writes the results into
299  * the axes and buttons arrays.
300  */
301 
302 static int sw_parse(unsigned char *buf, struct sw *sw)
303 {
304 	int hat, i, j;
305 	struct input_dev *dev;
306 
307 	switch (sw->type) {
308 
309 		case SW_ID_3DP:
310 
311 			if (sw_check(GB(0,64)) || (hat = (GB(6,1) << 3) | GB(60,3)) > 8)
312 				return -1;
313 
314 			dev = sw->dev[0];
315 
316 			input_report_abs(dev, ABS_X,        (GB( 3,3) << 7) | GB(16,7));
317 			input_report_abs(dev, ABS_Y,        (GB( 0,3) << 7) | GB(24,7));
318 			input_report_abs(dev, ABS_RZ,       (GB(35,2) << 7) | GB(40,7));
319 			input_report_abs(dev, ABS_THROTTLE, (GB(32,3) << 7) | GB(48,7));
320 
321 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
322 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
323 
324 			for (j = 0; j < 7; j++)
325 				input_report_key(dev, sw_btn[SW_ID_3DP][j], !GB(j+8,1));
326 
327 			input_report_key(dev, BTN_BASE4, !GB(38,1));
328 			input_report_key(dev, BTN_BASE5, !GB(37,1));
329 
330 			input_sync(dev);
331 
332 			return 0;
333 
334 		case SW_ID_GP:
335 
336 			for (i = 0; i < sw->number; i ++) {
337 
338 				if (sw_parity(GB(i*15,15)))
339 					return -1;
340 
341 				input_report_abs(sw->dev[i], ABS_X, GB(i*15+3,1) - GB(i*15+2,1));
342 				input_report_abs(sw->dev[i], ABS_Y, GB(i*15+0,1) - GB(i*15+1,1));
343 
344 				for (j = 0; j < 10; j++)
345 					input_report_key(sw->dev[i], sw_btn[SW_ID_GP][j], !GB(i*15+j+4,1));
346 
347 				input_sync(sw->dev[i]);
348 			}
349 
350 			return 0;
351 
352 		case SW_ID_PP:
353 		case SW_ID_FFP:
354 
355 			if (!sw_parity(GB(0,48)) || (hat = GB(42,4)) > 8)
356 				return -1;
357 
358 			dev = sw->dev[0];
359 			input_report_abs(dev, ABS_X,        GB( 9,10));
360 			input_report_abs(dev, ABS_Y,        GB(19,10));
361 			input_report_abs(dev, ABS_RZ,       GB(36, 6));
362 			input_report_abs(dev, ABS_THROTTLE, GB(29, 7));
363 
364 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
365 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
366 
367 			for (j = 0; j < 9; j++)
368 				input_report_key(dev, sw_btn[SW_ID_PP][j], !GB(j,1));
369 
370 			input_sync(dev);
371 
372 			return 0;
373 
374 		case SW_ID_FSP:
375 
376 			if (!sw_parity(GB(0,43)) || (hat = GB(28,4)) > 8)
377 				return -1;
378 
379 			dev = sw->dev[0];
380 			input_report_abs(dev, ABS_X,        GB( 0,10));
381 			input_report_abs(dev, ABS_Y,        GB(16,10));
382 			input_report_abs(dev, ABS_THROTTLE, GB(32, 6));
383 
384 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
385 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
386 
387 			for (j = 0; j < 6; j++)
388 				input_report_key(dev, sw_btn[SW_ID_FSP][j], !GB(j+10,1));
389 
390 			input_report_key(dev, BTN_TR,     !GB(26,1));
391 			input_report_key(dev, BTN_START,  !GB(27,1));
392 			input_report_key(dev, BTN_MODE,   !GB(38,1));
393 			input_report_key(dev, BTN_SELECT, !GB(39,1));
394 
395 			input_sync(dev);
396 
397 			return 0;
398 
399 		case SW_ID_FFW:
400 
401 			if (!sw_parity(GB(0,33)))
402 				return -1;
403 
404 			dev = sw->dev[0];
405 			input_report_abs(dev, ABS_RX,       GB( 0,10));
406 			input_report_abs(dev, ABS_RUDDER,   GB(10, 6));
407 			input_report_abs(dev, ABS_THROTTLE, GB(16, 6));
408 
409 			for (j = 0; j < 8; j++)
410 				input_report_key(dev, sw_btn[SW_ID_FFW][j], !GB(j+22,1));
411 
412 			input_sync(dev);
413 
414 			return 0;
415 	}
416 
417 	return -1;
418 }
419 
420 /*
421  * sw_read() reads SideWinder joystick data, and reinitializes
422  * the joystick in case of persistent problems. This is the function that is
423  * called from the generic code to poll the joystick.
424  */
425 
426 static int sw_read(struct sw *sw)
427 {
428 	unsigned char buf[SW_LENGTH];
429 	int i;
430 
431 	i = sw_read_packet(sw->gameport, buf, sw->length, 0);
432 
433 	if (sw->type == SW_ID_3DP && sw->length == 66 && i != 66) {		/* Broken packet, try to fix */
434 
435 		if (i == 64 && !sw_check(sw_get_bits(buf,0,64,1))) {		/* Last init failed, 1 bit mode */
436 			printk(KERN_WARNING "sidewinder.c: Joystick in wrong mode on %s"
437 				" - going to reinitialize.\n", sw->gameport->phys);
438 			sw->fail = SW_FAIL;					/* Reinitialize */
439 			i = 128;						/* Bogus value */
440 		}
441 
442 		if (i < 66 && GB(0,64) == GB(i*3-66,64))			/* 1 == 3 */
443 			i = 66;							/* Everything is fine */
444 
445 		if (i < 66 && GB(0,64) == GB(66,64))				/* 1 == 2 */
446 			i = 66;							/* Everything is fine */
447 
448 		if (i < 66 && GB(i*3-132,64) == GB(i*3-66,64)) {		/* 2 == 3 */
449 			memmove(buf, buf + i - 22, 22);				/* Move data */
450 			i = 66;							/* Carry on */
451 		}
452 	}
453 
454 	if (i == sw->length && !sw_parse(buf, sw)) {				/* Parse data */
455 
456 		sw->fail = 0;
457 		sw->ok++;
458 
459 		if (sw->type == SW_ID_3DP && sw->length == 66			/* Many packets OK */
460 			&& sw->ok > SW_OK) {
461 
462 			printk(KERN_INFO "sidewinder.c: No more trouble on %s"
463 				" - enabling optimization again.\n", sw->gameport->phys);
464 			sw->length = 22;
465 		}
466 
467 		return 0;
468 	}
469 
470 	sw->ok = 0;
471 	sw->fail++;
472 
473 	if (sw->type == SW_ID_3DP && sw->length == 22 && sw->fail > SW_BAD) {	/* Consecutive bad packets */
474 
475 		printk(KERN_INFO "sidewinder.c: Many bit errors on %s"
476 			" - disabling optimization.\n", sw->gameport->phys);
477 		sw->length = 66;
478 	}
479 
480 	if (sw->fail < SW_FAIL)
481 		return -1;							/* Not enough, don't reinitialize yet */
482 
483 	printk(KERN_WARNING "sidewinder.c: Too many bit errors on %s"
484 		" - reinitializing joystick.\n", sw->gameport->phys);
485 
486 	if (!i && sw->type == SW_ID_3DP) {					/* 3D Pro can be in analog mode */
487 		mdelay(3 * SW_TIMEOUT);
488 		sw_init_digital(sw->gameport);
489 	}
490 
491 	mdelay(SW_TIMEOUT);
492 	i = sw_read_packet(sw->gameport, buf, SW_LENGTH, 0);			/* Read normal data packet */
493 	mdelay(SW_TIMEOUT);
494 	sw_read_packet(sw->gameport, buf, SW_LENGTH, i);			/* Read ID packet, this initializes the stick */
495 
496 	sw->fail = SW_FAIL;
497 
498 	return -1;
499 }
500 
501 static void sw_poll(struct gameport *gameport)
502 {
503 	struct sw *sw = gameport_get_drvdata(gameport);
504 
505 	sw->reads++;
506 	if (sw_read(sw))
507 		sw->bads++;
508 }
509 
510 static int sw_open(struct input_dev *dev)
511 {
512 	struct sw *sw = input_get_drvdata(dev);
513 
514 	gameport_start_polling(sw->gameport);
515 	return 0;
516 }
517 
518 static void sw_close(struct input_dev *dev)
519 {
520 	struct sw *sw = input_get_drvdata(dev);
521 
522 	gameport_stop_polling(sw->gameport);
523 }
524 
525 /*
526  * sw_print_packet() prints the contents of a SideWinder packet.
527  */
528 
529 static void sw_print_packet(char *name, int length, unsigned char *buf, char bits)
530 {
531 	int i;
532 
533 	printk(KERN_INFO "sidewinder.c: %s packet, %d bits. [", name, length);
534 	for (i = (((length + 3) >> 2) - 1); i >= 0; i--)
535 		printk("%x", (int)sw_get_bits(buf, i << 2, 4, bits));
536 	printk("]\n");
537 }
538 
539 /*
540  * sw_3dp_id() translates the 3DP id into a human legible string.
541  * Unfortunately I don't know how to do this for the other SW types.
542  */
543 
544 static void sw_3dp_id(unsigned char *buf, char *comment, size_t size)
545 {
546 	int i;
547 	char pnp[8], rev[9];
548 
549 	for (i = 0; i < 7; i++)						/* ASCII PnP ID */
550 		pnp[i] = sw_get_bits(buf, 24+8*i, 8, 1);
551 
552 	for (i = 0; i < 8; i++)						/* ASCII firmware revision */
553 		rev[i] = sw_get_bits(buf, 88+8*i, 8, 1);
554 
555 	pnp[7] = rev[8] = 0;
556 
557 	snprintf(comment, size, " [PnP %d.%02d id %s rev %s]",
558 		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |		/* Two 6-bit values */
559 			sw_get_bits(buf, 16, 6, 1)) / 100,
560 		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |
561 			sw_get_bits(buf, 16, 6, 1)) % 100,
562 		 pnp, rev);
563 }
564 
565 /*
566  * sw_guess_mode() checks the upper two button bits for toggling -
567  * indication of that the joystick is in 3-bit mode. This is documented
568  * behavior for 3DP ID packet, and for example the FSP does this in
569  * normal packets instead. Fun ...
570  */
571 
572 static int sw_guess_mode(unsigned char *buf, int len)
573 {
574 	int i;
575 	unsigned char xor = 0;
576 
577 	for (i = 1; i < len; i++)
578 		xor |= (buf[i - 1] ^ buf[i]) & 6;
579 
580 	return !!xor * 2 + 1;
581 }
582 
583 /*
584  * sw_connect() probes for SideWinder type joysticks.
585  */
586 
587 static int sw_connect(struct gameport *gameport, struct gameport_driver *drv)
588 {
589 	struct sw *sw;
590 	struct input_dev *input_dev;
591 	int i, j, k, l;
592 	int err = 0;
593 	unsigned char *buf = NULL;	/* [SW_LENGTH] */
594 	unsigned char *idbuf = NULL;	/* [SW_LENGTH] */
595 	unsigned char m = 1;
596 	char comment[40];
597 
598 	comment[0] = 0;
599 
600 	sw = kzalloc(sizeof(struct sw), GFP_KERNEL);
601 	buf = kmalloc(SW_LENGTH, GFP_KERNEL);
602 	idbuf = kmalloc(SW_LENGTH, GFP_KERNEL);
603 	if (!sw || !buf || !idbuf) {
604 		err = -ENOMEM;
605 		goto fail1;
606 	}
607 
608 	sw->gameport = gameport;
609 
610 	gameport_set_drvdata(gameport, sw);
611 
612 	err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
613 	if (err)
614 		goto fail1;
615 
616 	dbg("Init 0: Opened %s, io %#x, speed %d",
617 		gameport->phys, gameport->io, gameport->speed);
618 
619 	i = sw_read_packet(gameport, buf, SW_LENGTH, 0);		/* Read normal packet */
620 	msleep(SW_TIMEOUT);
621 	dbg("Init 1: Mode %d. Length %d.", m , i);
622 
623 	if (!i) {							/* No data. 3d Pro analog mode? */
624 		sw_init_digital(gameport);				/* Switch to digital */
625 		msleep(SW_TIMEOUT);
626 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Retry reading packet */
627 		msleep(SW_TIMEOUT);
628 		dbg("Init 1b: Length %d.", i);
629 		if (!i) {						/* No data -> FAIL */
630 			err = -ENODEV;
631 			goto fail2;
632 		}
633 	}
634 
635 	j = sw_read_packet(gameport, idbuf, SW_LENGTH, i);		/* Read ID. This initializes the stick */
636 	m |= sw_guess_mode(idbuf, j);					/* ID packet should carry mode info [3DP] */
637 	dbg("Init 2: Mode %d. ID Length %d.", m, j);
638 
639 	if (j <= 0) {							/* Read ID failed. Happens in 1-bit mode on PP */
640 		msleep(SW_TIMEOUT);
641 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Retry reading packet */
642 		m |= sw_guess_mode(buf, i);
643 		dbg("Init 2b: Mode %d. Length %d.", m, i);
644 		if (!i) {
645 			err = -ENODEV;
646 			goto fail2;
647 		}
648 		msleep(SW_TIMEOUT);
649 		j = sw_read_packet(gameport, idbuf, SW_LENGTH, i);	/* Retry reading ID */
650 		dbg("Init 2c: ID Length %d.", j);
651 	}
652 
653 	sw->type = -1;
654 	k = SW_FAIL;							/* Try SW_FAIL times */
655 	l = 0;
656 
657 	do {
658 		k--;
659 		msleep(SW_TIMEOUT);
660 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Read data packet */
661 		dbg("Init 3: Mode %d. Length %d. Last %d. Tries %d.", m, i, l, k);
662 
663 		if (i > l) {						/* Longer? As we can only lose bits, it makes */
664 									/* no sense to try detection for a packet shorter */
665 			l = i;						/* than the previous one */
666 
667 			sw->number = 1;
668 			sw->gameport = gameport;
669 			sw->length = i;
670 			sw->bits = m;
671 
672 			dbg("Init 3a: Case %d.\n", i * m);
673 
674 			switch (i * m) {
675 				case 60:
676 					sw->number++;
677 				case 45:				/* Ambiguous packet length */
678 					if (j <= 40) {			/* ID length less or eq 40 -> FSP */
679 				case 43:
680 						sw->type = SW_ID_FSP;
681 						break;
682 					}
683 					sw->number++;
684 				case 30:
685 					sw->number++;
686 				case 15:
687 					sw->type = SW_ID_GP;
688 					break;
689 				case 33:
690 				case 31:
691 					sw->type = SW_ID_FFW;
692 					break;
693 				case 48:				/* Ambiguous */
694 					if (j == 14) {			/* ID length 14*3 -> FFP */
695 						sw->type = SW_ID_FFP;
696 						sprintf(comment, " [AC %s]", sw_get_bits(idbuf,38,1,3) ? "off" : "on");
697 					} else
698 						sw->type = SW_ID_PP;
699 					break;
700 				case 66:
701 					sw->bits = 3;
702 				case 198:
703 					sw->length = 22;
704 				case 64:
705 					sw->type = SW_ID_3DP;
706 					if (j == 160)
707 						sw_3dp_id(idbuf, comment, sizeof(comment));
708 					break;
709 			}
710 		}
711 
712 	} while (k && sw->type == -1);
713 
714 	if (sw->type == -1) {
715 		printk(KERN_WARNING "sidewinder.c: unknown joystick device detected "
716 			"on %s, contact <vojtech@ucw.cz>\n", gameport->phys);
717 		sw_print_packet("ID", j * 3, idbuf, 3);
718 		sw_print_packet("Data", i * m, buf, m);
719 		err = -ENODEV;
720 		goto fail2;
721 	}
722 
723 #ifdef SW_DEBUG
724 	sw_print_packet("ID", j * 3, idbuf, 3);
725 	sw_print_packet("Data", i * m, buf, m);
726 #endif
727 
728 	gameport_set_poll_handler(gameport, sw_poll);
729 	gameport_set_poll_interval(gameport, 20);
730 
731 	k = i;
732 	l = j;
733 
734 	for (i = 0; i < sw->number; i++) {
735 		int bits, code;
736 
737 		snprintf(sw->name, sizeof(sw->name),
738 			 "Microsoft SideWinder %s", sw_name[sw->type]);
739 		snprintf(sw->phys[i], sizeof(sw->phys[i]),
740 			 "%s/input%d", gameport->phys, i);
741 
742 		sw->dev[i] = input_dev = input_allocate_device();
743 		if (!input_dev) {
744 			err = -ENOMEM;
745 			goto fail3;
746 		}
747 
748 		input_dev->name = sw->name;
749 		input_dev->phys = sw->phys[i];
750 		input_dev->id.bustype = BUS_GAMEPORT;
751 		input_dev->id.vendor = GAMEPORT_ID_VENDOR_MICROSOFT;
752 		input_dev->id.product = sw->type;
753 		input_dev->id.version = 0x0100;
754 		input_dev->dev.parent = &gameport->dev;
755 
756 		input_set_drvdata(input_dev, sw);
757 
758 		input_dev->open = sw_open;
759 		input_dev->close = sw_close;
760 
761 		input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
762 
763 		for (j = 0; (bits = sw_bit[sw->type][j]); j++) {
764 			int min, max, fuzz, flat;
765 
766 			code = sw_abs[sw->type][j];
767 			min = bits == 1 ? -1 : 0;
768 			max = (1 << bits) - 1;
769 			fuzz = (bits >> 1) >= 2 ? 1 << ((bits >> 1) - 2) : 0;
770 			flat = code == ABS_THROTTLE || bits < 5 ?
771 				0 : 1 << (bits - 5);
772 
773 			input_set_abs_params(input_dev, code,
774 					     min, max, fuzz, flat);
775 		}
776 
777 		for (j = 0; (code = sw_btn[sw->type][j]); j++)
778 			__set_bit(code, input_dev->keybit);
779 
780 		dbg("%s%s [%d-bit id %d data %d]\n", sw->name, comment, m, l, k);
781 
782 		err = input_register_device(sw->dev[i]);
783 		if (err)
784 			goto fail4;
785 	}
786 
787  out:	kfree(buf);
788 	kfree(idbuf);
789 
790 	return err;
791 
792  fail4:	input_free_device(sw->dev[i]);
793  fail3:	while (--i >= 0)
794 		input_unregister_device(sw->dev[i]);
795  fail2:	gameport_close(gameport);
796  fail1:	gameport_set_drvdata(gameport, NULL);
797 	kfree(sw);
798 	goto out;
799 }
800 
801 static void sw_disconnect(struct gameport *gameport)
802 {
803 	struct sw *sw = gameport_get_drvdata(gameport);
804 	int i;
805 
806 	for (i = 0; i < sw->number; i++)
807 		input_unregister_device(sw->dev[i]);
808 	gameport_close(gameport);
809 	gameport_set_drvdata(gameport, NULL);
810 	kfree(sw);
811 }
812 
813 static struct gameport_driver sw_drv = {
814 	.driver		= {
815 		.name	= "sidewinder",
816 		.owner	= THIS_MODULE,
817 	},
818 	.description	= DRIVER_DESC,
819 	.connect	= sw_connect,
820 	.disconnect	= sw_disconnect,
821 };
822 
823 static int __init sw_init(void)
824 {
825 	return gameport_register_driver(&sw_drv);
826 }
827 
828 static void __exit sw_exit(void)
829 {
830 	gameport_unregister_driver(&sw_drv);
831 }
832 
833 module_init(sw_init);
834 module_exit(sw_exit);
835