xref: /linux/drivers/input/joystick/sidewinder.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
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 
37 #define DRIVER_DESC	"Microsoft SideWinder joystick family driver"
38 
39 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
40 MODULE_DESCRIPTION(DRIVER_DESC);
41 MODULE_LICENSE("GPL");
42 
43 /*
44  * These are really magic values. Changing them can make a problem go away,
45  * as well as break everything.
46  */
47 
48 #undef SW_DEBUG
49 #undef SW_DEBUG_DATA
50 
51 #define SW_START	600	/* The time we wait for the first bit [600 us] */
52 #define SW_STROBE	60	/* Max time per bit [60 us] */
53 #define SW_TIMEOUT	6	/* Wait for everything to settle [6 ms] */
54 #define SW_KICK		45	/* Wait after A0 fall till kick [45 us] */
55 #define SW_END		8	/* Number of bits before end of packet to kick */
56 #define SW_FAIL		16	/* Number of packet read errors to fail and reinitialize */
57 #define SW_BAD		2	/* Number of packet read errors to switch off 3d Pro optimization */
58 #define SW_OK		64	/* Number of packet read successes to switch optimization back on */
59 #define SW_LENGTH	512	/* Max number of bits in a packet */
60 
61 #ifdef SW_DEBUG
62 #define dbg(format, arg...) printk(KERN_DEBUG __FILE__ ": " format "\n" , ## arg)
63 #else
64 #define dbg(format, arg...) do {} while (0)
65 #endif
66 
67 /*
68  * SideWinder joystick types ...
69  */
70 
71 #define SW_ID_3DP	0
72 #define SW_ID_GP	1
73 #define SW_ID_PP	2
74 #define SW_ID_FFP	3
75 #define SW_ID_FSP	4
76 #define SW_ID_FFW	5
77 
78 /*
79  * Names, buttons, axes ...
80  */
81 
82 static char *sw_name[] = {	"3D Pro", "GamePad", "Precision Pro", "Force Feedback Pro", "FreeStyle Pro",
83 				"Force Feedback Wheel" };
84 
85 static char sw_abs[][7] = {
86 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
87 	{ ABS_X, ABS_Y },
88 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
89 	{ ABS_X, ABS_Y, ABS_RZ, ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
90 	{ ABS_X, ABS_Y,         ABS_THROTTLE, ABS_HAT0X, ABS_HAT0Y },
91 	{ ABS_RX, ABS_RUDDER,   ABS_THROTTLE }};
92 
93 static char sw_bit[][7] = {
94 	{ 10, 10,  9, 10,  1,  1 },
95 	{  1,  1                 },
96 	{ 10, 10,  6,  7,  1,  1 },
97 	{ 10, 10,  6,  7,  1,  1 },
98 	{ 10, 10,  6,  1,  1     },
99 	{ 10,  7,  7,  1,  1     }};
100 
101 static short sw_btn[][12] = {
102 	{ BTN_TRIGGER, BTN_TOP, BTN_THUMB, BTN_THUMB2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_MODE },
103 	{ BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, BTN_TL, BTN_TR, BTN_START, BTN_MODE },
104 	{ BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_SELECT },
105 	{ BTN_TRIGGER, BTN_THUMB, BTN_TOP, BTN_TOP2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4, BTN_SELECT },
106 	{ BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, BTN_TL, BTN_TR, BTN_START, BTN_MODE, BTN_SELECT },
107 	{ BTN_TRIGGER, BTN_TOP, BTN_THUMB, BTN_THUMB2, BTN_BASE, BTN_BASE2, BTN_BASE3, BTN_BASE4 }};
108 
109 static struct {
110 	int x;
111 	int y;
112 } sw_hat_to_axis[] = {{ 0, 0}, { 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}};
113 
114 struct sw {
115 	struct gameport *gameport;
116 	struct input_dev dev[4];
117 	char name[64];
118 	char phys[4][32];
119 	int length;
120 	int type;
121 	int bits;
122 	int number;
123 	int fail;
124 	int ok;
125 	int reads;
126 	int bads;
127 };
128 
129 /*
130  * sw_read_packet() is a function which reads either a data packet, or an
131  * identification packet from a SideWinder joystick. The protocol is very,
132  * very, very braindamaged. Microsoft patented it in US patent #5628686.
133  */
134 
135 static int sw_read_packet(struct gameport *gameport, unsigned char *buf, int length, int id)
136 {
137 	unsigned long flags;
138 	int timeout, bitout, sched, i, kick, start, strobe;
139 	unsigned char pending, u, v;
140 
141 	i = -id;						/* Don't care about data, only want ID */
142 	timeout = id ? gameport_time(gameport, SW_TIMEOUT * 1000) : 0; /* Set up global timeout for ID packet */
143 	kick = id ? gameport_time(gameport, SW_KICK) : 0;	/* Set up kick timeout for ID packet */
144 	start = gameport_time(gameport, SW_START);
145 	strobe = gameport_time(gameport, SW_STROBE);
146 	bitout = start;
147 	pending = 0;
148 	sched = 0;
149 
150         local_irq_save(flags);					/* Quiet, please */
151 
152 	gameport_trigger(gameport);				/* Trigger */
153 	v = gameport_read(gameport);
154 
155 	do {
156 		bitout--;
157 		u = v;
158 		v = gameport_read(gameport);
159 	} while (!(~v & u & 0x10) && (bitout > 0));		/* Wait for first falling edge on clock */
160 
161 	if (bitout > 0)
162 		bitout = strobe;				/* Extend time if not timed out */
163 
164 	while ((timeout > 0 || bitout > 0) && (i < length)) {
165 
166 		timeout--;
167 		bitout--;					/* Decrement timers */
168 		sched--;
169 
170 		u = v;
171 		v = gameport_read(gameport);
172 
173 		if ((~u & v & 0x10) && (bitout > 0)) {		/* Rising edge on clock - data bit */
174 			if (i >= 0)				/* Want this data */
175 				buf[i] = v >> 5;		/* Store it */
176 			i++;					/* Advance index */
177 			bitout = strobe;			/* Extend timeout for next bit */
178 		}
179 
180 		if (kick && (~v & u & 0x01)) {			/* Falling edge on axis 0 */
181 			sched = kick;				/* Schedule second trigger */
182 			kick = 0;				/* Don't schedule next time on falling edge */
183 			pending = 1;				/* Mark schedule */
184 		}
185 
186 		if (pending && sched < 0 && (i > -SW_END)) {	/* Second trigger time */
187 			gameport_trigger(gameport);		/* Trigger */
188 			bitout = start;				/* Long bit timeout */
189 			pending = 0;				/* Unmark schedule */
190 			timeout = 0;				/* Switch from global to bit timeouts */
191 		}
192 	}
193 
194 	local_irq_restore(flags);					/* Done - relax */
195 
196 #ifdef SW_DEBUG_DATA
197 	{
198 		int j;
199 		printk(KERN_DEBUG "sidewinder.c: Read %d triplets. [", i);
200 		for (j = 0; j < i; j++) printk("%d", buf[j]);
201 		printk("]\n");
202 	}
203 #endif
204 
205 	return i;
206 }
207 
208 /*
209  * sw_get_bits() and GB() compose bits from the triplet buffer into a __u64.
210  * Parameter 'pos' is bit number inside packet where to start at, 'num' is number
211  * of bits to be read, 'shift' is offset in the resulting __u64 to start at, bits
212  * is number of bits per triplet.
213  */
214 
215 #define GB(pos,num) sw_get_bits(buf, pos, num, sw->bits)
216 
217 static __u64 sw_get_bits(unsigned char *buf, int pos, int num, char bits)
218 {
219 	__u64 data = 0;
220 	int tri = pos % bits;						/* Start position */
221 	int i   = pos / bits;
222 	int bit = 0;
223 
224 	while (num--) {
225 		data |= (__u64)((buf[i] >> tri++) & 1) << bit++;	/* Transfer bit */
226 		if (tri == bits) {
227 			i++;						/* Next triplet */
228 			tri = 0;
229 		}
230 	}
231 
232 	return data;
233 }
234 
235 /*
236  * sw_init_digital() initializes a SideWinder 3D Pro joystick
237  * into digital mode.
238  */
239 
240 static void sw_init_digital(struct gameport *gameport)
241 {
242 	int seq[] = { 140, 140+725, 140+300, 0 };
243 	unsigned long flags;
244 	int i, t;
245 
246         local_irq_save(flags);
247 
248 	i = 0;
249         do {
250                 gameport_trigger(gameport);			/* Trigger */
251 		t = gameport_time(gameport, SW_TIMEOUT * 1000);
252 		while ((gameport_read(gameport) & 1) && t) t--;	/* Wait for axis to fall back to 0 */
253                 udelay(seq[i]);					/* Delay magic time */
254         } while (seq[++i]);
255 
256 	gameport_trigger(gameport);				/* Last trigger */
257 
258 	local_irq_restore(flags);
259 }
260 
261 /*
262  * sw_parity() computes parity of __u64
263  */
264 
265 static int sw_parity(__u64 t)
266 {
267 	int x = t ^ (t >> 32);
268 
269 	x ^= x >> 16;
270 	x ^= x >> 8;
271 	x ^= x >> 4;
272 	x ^= x >> 2;
273 	x ^= x >> 1;
274 	return x & 1;
275 }
276 
277 /*
278  * sw_ccheck() checks synchronization bits and computes checksum of nibbles.
279  */
280 
281 static int sw_check(__u64 t)
282 {
283 	unsigned char sum = 0;
284 
285 	if ((t & 0x8080808080808080ULL) ^ 0x80)			/* Sync */
286 		return -1;
287 
288 	while (t) {						/* Sum */
289 		sum += t & 0xf;
290 		t >>= 4;
291 	}
292 
293 	return sum & 0xf;
294 }
295 
296 /*
297  * sw_parse() analyzes SideWinder joystick data, and writes the results into
298  * the axes and buttons arrays.
299  */
300 
301 static int sw_parse(unsigned char *buf, struct sw *sw)
302 {
303 	int hat, i, j;
304 	struct input_dev *dev = sw->dev;
305 
306 	switch (sw->type) {
307 
308 		case SW_ID_3DP:
309 
310 			if (sw_check(GB(0,64)) || (hat = (GB(6,1) << 3) | GB(60,3)) > 8)
311 				return -1;
312 
313 			input_report_abs(dev, ABS_X,        (GB( 3,3) << 7) | GB(16,7));
314 			input_report_abs(dev, ABS_Y,        (GB( 0,3) << 7) | GB(24,7));
315 			input_report_abs(dev, ABS_RZ,       (GB(35,2) << 7) | GB(40,7));
316 			input_report_abs(dev, ABS_THROTTLE, (GB(32,3) << 7) | GB(48,7));
317 
318 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
319 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
320 
321 			for (j = 0; j < 7; j++)
322 				input_report_key(dev, sw_btn[SW_ID_3DP][j], !GB(j+8,1));
323 
324 			input_report_key(dev, BTN_BASE4, !GB(38,1));
325 			input_report_key(dev, BTN_BASE5, !GB(37,1));
326 
327 			input_sync(dev);
328 
329 			return 0;
330 
331 		case SW_ID_GP:
332 
333 			for (i = 0; i < sw->number; i ++) {
334 
335 				if (sw_parity(GB(i*15,15)))
336 					return -1;
337 
338 				input_report_abs(dev + i, ABS_X, GB(i*15+3,1) - GB(i*15+2,1));
339 				input_report_abs(dev + i, ABS_Y, GB(i*15+0,1) - GB(i*15+1,1));
340 
341 				for (j = 0; j < 10; j++)
342 					input_report_key(dev + i, sw_btn[SW_ID_GP][j], !GB(i*15+j+4,1));
343 
344 				input_sync(dev + i);
345 			}
346 
347 			return 0;
348 
349 		case SW_ID_PP:
350 		case SW_ID_FFP:
351 
352 			if (!sw_parity(GB(0,48)) || (hat = GB(42,4)) > 8)
353 				return -1;
354 
355 			input_report_abs(dev, ABS_X,        GB( 9,10));
356 			input_report_abs(dev, ABS_Y,        GB(19,10));
357 			input_report_abs(dev, ABS_RZ,       GB(36, 6));
358 			input_report_abs(dev, ABS_THROTTLE, GB(29, 7));
359 
360 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
361 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
362 
363 			for (j = 0; j < 9; j++)
364 				input_report_key(dev, sw_btn[SW_ID_PP][j], !GB(j,1));
365 
366 			input_sync(dev);
367 
368 			return 0;
369 
370 		case SW_ID_FSP:
371 
372 			if (!sw_parity(GB(0,43)) || (hat = GB(28,4)) > 8)
373 				return -1;
374 
375 			input_report_abs(dev, ABS_X,        GB( 0,10));
376 			input_report_abs(dev, ABS_Y,        GB(16,10));
377 			input_report_abs(dev, ABS_THROTTLE, GB(32, 6));
378 
379 			input_report_abs(dev, ABS_HAT0X, sw_hat_to_axis[hat].x);
380 			input_report_abs(dev, ABS_HAT0Y, sw_hat_to_axis[hat].y);
381 
382 			for (j = 0; j < 6; j++)
383 				input_report_key(dev, sw_btn[SW_ID_FSP][j], !GB(j+10,1));
384 
385 			input_report_key(dev, BTN_TR,     !GB(26,1));
386 			input_report_key(dev, BTN_START,  !GB(27,1));
387 			input_report_key(dev, BTN_MODE,   !GB(38,1));
388 			input_report_key(dev, BTN_SELECT, !GB(39,1));
389 
390 			input_sync(dev);
391 
392 			return 0;
393 
394 		case SW_ID_FFW:
395 
396 			if (!sw_parity(GB(0,33)))
397 				return -1;
398 
399 			input_report_abs(dev, ABS_RX,       GB( 0,10));
400 			input_report_abs(dev, ABS_RUDDER,   GB(10, 6));
401 			input_report_abs(dev, ABS_THROTTLE, GB(16, 6));
402 
403 			for (j = 0; j < 8; j++)
404 				input_report_key(dev, sw_btn[SW_ID_FFW][j], !GB(j+22,1));
405 
406 			input_sync(dev);
407 
408 			return 0;
409 	}
410 
411 	return -1;
412 }
413 
414 /*
415  * sw_read() reads SideWinder joystick data, and reinitializes
416  * the joystick in case of persistent problems. This is the function that is
417  * called from the generic code to poll the joystick.
418  */
419 
420 static int sw_read(struct sw *sw)
421 {
422 	unsigned char buf[SW_LENGTH];
423 	int i;
424 
425 	i = sw_read_packet(sw->gameport, buf, sw->length, 0);
426 
427 	if (sw->type == SW_ID_3DP && sw->length == 66 && i != 66) {		/* Broken packet, try to fix */
428 
429 		if (i == 64 && !sw_check(sw_get_bits(buf,0,64,1))) {		/* Last init failed, 1 bit mode */
430 			printk(KERN_WARNING "sidewinder.c: Joystick in wrong mode on %s"
431 				" - going to reinitialize.\n", sw->gameport->phys);
432 			sw->fail = SW_FAIL;					/* Reinitialize */
433 			i = 128;						/* Bogus value */
434 		}
435 
436 		if (i < 66 && GB(0,64) == GB(i*3-66,64))			/* 1 == 3 */
437 			i = 66;							/* Everything is fine */
438 
439 		if (i < 66 && GB(0,64) == GB(66,64))				/* 1 == 2 */
440 			i = 66;							/* Everything is fine */
441 
442 		if (i < 66 && GB(i*3-132,64) == GB(i*3-66,64)) {		/* 2 == 3 */
443 			memmove(buf, buf + i - 22, 22);				/* Move data */
444 			i = 66;							/* Carry on */
445 		}
446 	}
447 
448 	if (i == sw->length && !sw_parse(buf, sw)) {				/* Parse data */
449 
450 		sw->fail = 0;
451 		sw->ok++;
452 
453 		if (sw->type == SW_ID_3DP && sw->length == 66			/* Many packets OK */
454 			&& sw->ok > SW_OK) {
455 
456 			printk(KERN_INFO "sidewinder.c: No more trouble on %s"
457 				" - enabling optimization again.\n", sw->gameport->phys);
458 			sw->length = 22;
459 		}
460 
461 		return 0;
462 	}
463 
464 	sw->ok = 0;
465 	sw->fail++;
466 
467 	if (sw->type == SW_ID_3DP && sw->length == 22 && sw->fail > SW_BAD) {	/* Consecutive bad packets */
468 
469 		printk(KERN_INFO "sidewinder.c: Many bit errors on %s"
470 			" - disabling optimization.\n", sw->gameport->phys);
471 		sw->length = 66;
472 	}
473 
474 	if (sw->fail < SW_FAIL)
475 		return -1;							/* Not enough, don't reinitialize yet */
476 
477 	printk(KERN_WARNING "sidewinder.c: Too many bit errors on %s"
478 		" - reinitializing joystick.\n", sw->gameport->phys);
479 
480 	if (!i && sw->type == SW_ID_3DP) {					/* 3D Pro can be in analog mode */
481 		mdelay(3 * SW_TIMEOUT);
482 		sw_init_digital(sw->gameport);
483 	}
484 
485 	mdelay(SW_TIMEOUT);
486 	i = sw_read_packet(sw->gameport, buf, SW_LENGTH, 0);			/* Read normal data packet */
487 	mdelay(SW_TIMEOUT);
488 	sw_read_packet(sw->gameport, buf, SW_LENGTH, i);			/* Read ID packet, this initializes the stick */
489 
490 	sw->fail = SW_FAIL;
491 
492 	return -1;
493 }
494 
495 static void sw_poll(struct gameport *gameport)
496 {
497 	struct sw *sw = gameport_get_drvdata(gameport);
498 
499 	sw->reads++;
500 	if (sw_read(sw))
501 		sw->bads++;
502 }
503 
504 static int sw_open(struct input_dev *dev)
505 {
506 	struct sw *sw = dev->private;
507 
508 	gameport_start_polling(sw->gameport);
509 	return 0;
510 }
511 
512 static void sw_close(struct input_dev *dev)
513 {
514 	struct sw *sw = dev->private;
515 
516 	gameport_stop_polling(sw->gameport);
517 }
518 
519 /*
520  * sw_print_packet() prints the contents of a SideWinder packet.
521  */
522 
523 static void sw_print_packet(char *name, int length, unsigned char *buf, char bits)
524 {
525 	int i;
526 
527 	printk(KERN_INFO "sidewinder.c: %s packet, %d bits. [", name, length);
528 	for (i = (((length + 3) >> 2) - 1); i >= 0; i--)
529 		printk("%x", (int)sw_get_bits(buf, i << 2, 4, bits));
530 	printk("]\n");
531 }
532 
533 /*
534  * sw_3dp_id() translates the 3DP id into a human legible string.
535  * Unfortunately I don't know how to do this for the other SW types.
536  */
537 
538 static void sw_3dp_id(unsigned char *buf, char *comment)
539 {
540 	int i;
541 	char pnp[8], rev[9];
542 
543 	for (i = 0; i < 7; i++)						/* ASCII PnP ID */
544 		pnp[i] = sw_get_bits(buf, 24+8*i, 8, 1);
545 
546 	for (i = 0; i < 8; i++)						/* ASCII firmware revision */
547 		rev[i] = sw_get_bits(buf, 88+8*i, 8, 1);
548 
549 	pnp[7] = rev[8] = 0;
550 
551 	sprintf(comment, " [PnP %d.%02d id %s rev %s]",
552 		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |		/* Two 6-bit values */
553 			sw_get_bits(buf, 16, 6, 1)) / 100,
554 		(int) ((sw_get_bits(buf, 8, 6, 1) << 6) |
555 			sw_get_bits(buf, 16, 6, 1)) % 100,
556 		 pnp, rev);
557 }
558 
559 /*
560  * sw_guess_mode() checks the upper two button bits for toggling -
561  * indication of that the joystick is in 3-bit mode. This is documented
562  * behavior for 3DP ID packet, and for example the FSP does this in
563  * normal packets instead. Fun ...
564  */
565 
566 static int sw_guess_mode(unsigned char *buf, int len)
567 {
568 	int i;
569 	unsigned char xor = 0;
570 
571 	for (i = 1; i < len; i++)
572 		xor |= (buf[i - 1] ^ buf[i]) & 6;
573 
574 	return !!xor * 2 + 1;
575 }
576 
577 /*
578  * sw_connect() probes for SideWinder type joysticks.
579  */
580 
581 static int sw_connect(struct gameport *gameport, struct gameport_driver *drv)
582 {
583 	struct sw *sw;
584 	int i, j, k, l;
585 	int err;
586 	unsigned char *buf = NULL;	/* [SW_LENGTH] */
587 	unsigned char *idbuf = NULL;	/* [SW_LENGTH] */
588 	unsigned char m = 1;
589 	char comment[40];
590 
591 	comment[0] = 0;
592 
593 	sw = kzalloc(sizeof(struct sw), GFP_KERNEL);
594 	buf = kmalloc(SW_LENGTH, GFP_KERNEL);
595 	idbuf = kmalloc(SW_LENGTH, GFP_KERNEL);
596 	if (!sw || !buf || !idbuf) {
597 		err = -ENOMEM;
598 		goto fail1;
599 	}
600 
601 	sw->gameport = gameport;
602 
603 	gameport_set_drvdata(gameport, sw);
604 
605 	err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
606 	if (err)
607 		goto fail1;
608 
609 	dbg("Init 0: Opened %s, io %#x, speed %d",
610 		gameport->phys, gameport->io, gameport->speed);
611 
612 	i = sw_read_packet(gameport, buf, SW_LENGTH, 0);		/* Read normal packet */
613 	msleep(SW_TIMEOUT);
614 	dbg("Init 1: Mode %d. Length %d.", m , i);
615 
616 	if (!i) {							/* No data. 3d Pro analog mode? */
617 		sw_init_digital(gameport);				/* Switch to digital */
618 		msleep(SW_TIMEOUT);
619 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Retry reading packet */
620 		msleep(SW_TIMEOUT);
621 		dbg("Init 1b: Length %d.", i);
622 		if (!i) {						/* No data -> FAIL */
623 			err = -ENODEV;
624 			goto fail2;
625 		}
626 	}
627 
628 	j = sw_read_packet(gameport, idbuf, SW_LENGTH, i);		/* Read ID. This initializes the stick */
629 	m |= sw_guess_mode(idbuf, j);					/* ID packet should carry mode info [3DP] */
630 	dbg("Init 2: Mode %d. ID Length %d.", m, j);
631 
632 	if (j <= 0) {							/* Read ID failed. Happens in 1-bit mode on PP */
633 		msleep(SW_TIMEOUT);
634 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Retry reading packet */
635 		m |= sw_guess_mode(buf, i);
636 		dbg("Init 2b: Mode %d. Length %d.", m, i);
637 		if (!i) {
638 			err = -ENODEV;
639 			goto fail2;
640 		}
641 		msleep(SW_TIMEOUT);
642 		j = sw_read_packet(gameport, idbuf, SW_LENGTH, i);	/* Retry reading ID */
643 		dbg("Init 2c: ID Length %d.", j);
644 	}
645 
646 	sw->type = -1;
647 	k = SW_FAIL;							/* Try SW_FAIL times */
648 	l = 0;
649 
650 	do {
651 		k--;
652 		msleep(SW_TIMEOUT);
653 		i = sw_read_packet(gameport, buf, SW_LENGTH, 0);	/* Read data packet */
654 		dbg("Init 3: Mode %d. Length %d. Last %d. Tries %d.", m, i, l, k);
655 
656 		if (i > l) {						/* Longer? As we can only lose bits, it makes */
657 									/* no sense to try detection for a packet shorter */
658 			l = i;						/* than the previous one */
659 
660 			sw->number = 1;
661 			sw->gameport = gameport;
662 			sw->length = i;
663 			sw->bits = m;
664 
665 			dbg("Init 3a: Case %d.\n", i * m);
666 
667 			switch (i * m) {
668 				case 60:
669 					sw->number++;
670 				case 45:				/* Ambiguous packet length */
671 					if (j <= 40) {			/* ID length less or eq 40 -> FSP */
672 				case 43:
673 						sw->type = SW_ID_FSP;
674 						break;
675 					}
676 					sw->number++;
677 				case 30:
678 					sw->number++;
679 				case 15:
680 					sw->type = SW_ID_GP;
681 					break;
682 				case 33:
683 				case 31:
684 					sw->type = SW_ID_FFW;
685 					break;
686 				case 48:				/* Ambiguous */
687 					if (j == 14) {			/* ID length 14*3 -> FFP */
688 						sw->type = SW_ID_FFP;
689 						sprintf(comment, " [AC %s]", sw_get_bits(idbuf,38,1,3) ? "off" : "on");
690 					} else
691 					sw->type = SW_ID_PP;
692 					break;
693 				case 66:
694 					sw->bits = 3;
695 				case 198:
696 					sw->length = 22;
697 				case 64:
698 					sw->type = SW_ID_3DP;
699 					if (j == 160) sw_3dp_id(idbuf, comment);
700 					break;
701 			}
702 		}
703 
704 	} while (k && sw->type == -1);
705 
706 	if (sw->type == -1) {
707 		printk(KERN_WARNING "sidewinder.c: unknown joystick device detected "
708 			"on %s, contact <vojtech@ucw.cz>\n", gameport->phys);
709 		sw_print_packet("ID", j * 3, idbuf, 3);
710 		sw_print_packet("Data", i * m, buf, m);
711 		err = -ENODEV;
712 		goto fail2;
713 	}
714 
715 #ifdef SW_DEBUG
716 	sw_print_packet("ID", j * 3, idbuf, 3);
717 	sw_print_packet("Data", i * m, buf, m);
718 #endif
719 
720 	gameport_set_poll_handler(gameport, sw_poll);
721 	gameport_set_poll_interval(gameport, 20);
722 
723 	k = i;
724 	l = j;
725 
726 	for (i = 0; i < sw->number; i++) {
727 		int bits, code;
728 
729 		sprintf(sw->name, "Microsoft SideWinder %s", sw_name[sw->type]);
730 		sprintf(sw->phys[i], "%s/input%d", gameport->phys, i);
731 
732 		sw->dev[i].private = sw;
733 
734 		sw->dev[i].open = sw_open;
735 		sw->dev[i].close = sw_close;
736 
737 		sw->dev[i].name = sw->name;
738 		sw->dev[i].phys = sw->phys[i];
739 		sw->dev[i].id.bustype = BUS_GAMEPORT;
740 		sw->dev[i].id.vendor = GAMEPORT_ID_VENDOR_MICROSOFT;
741 		sw->dev[i].id.product = sw->type;
742 		sw->dev[i].id.version = 0x0100;
743 
744 		sw->dev[i].evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
745 
746 		for (j = 0; (bits = sw_bit[sw->type][j]); j++) {
747 			code = sw_abs[sw->type][j];
748 			set_bit(code, sw->dev[i].absbit);
749 			sw->dev[i].absmax[code] = (1 << bits) - 1;
750 			sw->dev[i].absmin[code] = (bits == 1) ? -1 : 0;
751 			sw->dev[i].absfuzz[code] = ((bits >> 1) >= 2) ? (1 << ((bits >> 1) - 2)) : 0;
752 			if (code != ABS_THROTTLE)
753 				sw->dev[i].absflat[code] = (bits >= 5) ? (1 << (bits - 5)) : 0;
754 		}
755 
756 		for (j = 0; (code = sw_btn[sw->type][j]); j++)
757 			set_bit(code, sw->dev[i].keybit);
758 
759 		input_register_device(sw->dev + i);
760 		printk(KERN_INFO "input: %s%s on %s [%d-bit id %d data %d]\n",
761 			sw->name, comment, gameport->phys, m, l, k);
762 	}
763 
764 	return 0;
765 
766 fail2:	gameport_close(gameport);
767 fail1:	gameport_set_drvdata(gameport, NULL);
768 	kfree(sw);
769 	kfree(buf);
770 	kfree(idbuf);
771 	return err;
772 }
773 
774 static void sw_disconnect(struct gameport *gameport)
775 {
776 	struct sw *sw = gameport_get_drvdata(gameport);
777 	int i;
778 
779 	for (i = 0; i < sw->number; i++)
780 		input_unregister_device(sw->dev + i);
781 	gameport_close(gameport);
782 	gameport_set_drvdata(gameport, NULL);
783 	kfree(sw);
784 }
785 
786 static struct gameport_driver sw_drv = {
787 	.driver		= {
788 		.name	= "sidewinder",
789 	},
790 	.description	= DRIVER_DESC,
791 	.connect	= sw_connect,
792 	.disconnect	= sw_disconnect,
793 };
794 
795 static int __init sw_init(void)
796 {
797 	gameport_register_driver(&sw_drv);
798 	return 0;
799 }
800 
801 static void __exit sw_exit(void)
802 {
803 	gameport_unregister_driver(&sw_drv);
804 }
805 
806 module_init(sw_init);
807 module_exit(sw_exit);
808