xref: /dragonfly/sys/dev/disk/vpo/immio.c (revision 3851e4b8)
1 /*-
2  * Copyright (c) 1998, 1999 Nicolas Souchu
3  * Copyright (c) 2001 Alcove - Nicolas Souchu
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD: src/sys/dev/ppbus/immio.c,v 1.10.2.3 2001/10/02 05:27:20 nsouch Exp $
28  */
29 
30 /*
31  * Iomega ZIP+ Matchmaker Parallel Port Interface driver
32  *
33  * Thanks to David Campbell work on the Linux driver and the Iomega specs
34  * Thanks to Thiebault Moeglin for the drive
35  */
36 #ifdef _KERNEL
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/module.h>
40 #include <sys/bus.h>
41 #include <sys/malloc.h>
42 
43 #endif	/* _KERNEL */
44 
45 #include "opt_vpo.h"
46 
47 #include <bus/ppbus/ppbio.h>
48 #include <bus/ppbus/ppbconf.h>
49 #include <bus/ppbus/ppb_msq.h>
50 #include "vpoio.h"
51 #include <bus/ppbus/ppb_1284.h>
52 
53 #include "ppbus_if.h"
54 
55 #define VP0_SELTMO		5000	/* select timeout */
56 #define VP0_FAST_SPINTMO	500000	/* wait status timeout */
57 #define VP0_LOW_SPINTMO		5000000	/* wait status timeout */
58 
59 #define VP0_SECTOR_SIZE	512
60 
61 /*
62  * Microcode to execute very fast I/O sequences at the lowest bus level.
63  */
64 
65 #define WAIT_RET		MS_PARAM(7, 2, MS_TYP_PTR)
66 #define WAIT_TMO		MS_PARAM(1, 0, MS_TYP_INT)
67 
68 #define DECLARE_WAIT_MICROSEQUENCE \
69 struct ppb_microseq wait_microseq[] = {					\
70 	MS_CASS(0x0c),							\
71 	MS_SET(MS_UNKNOWN),						\
72 	/* loop */							\
73 	MS_BRSET(nBUSY, 4 /* ready */),					\
74 	MS_DBRA(-2 /* loop */),						\
75 	MS_CASS(0x04),							\
76 	MS_RET(1), /* timed out */					\
77 	/* ready */							\
78 	MS_CASS(0x04),							\
79 	MS_RFETCH(MS_REG_STR, 0xb8, MS_UNKNOWN ),			\
80 	MS_RET(0) /* no error */					\
81 }
82 
83 #define SELECT_TARGET		MS_PARAM(6, 1, MS_TYP_CHA)
84 
85 #define DECLARE_SELECT_MICROSEQUENCE \
86 struct ppb_microseq select_microseq[] = {				\
87 	MS_CASS(0xc),							\
88 	/* first, check there is nothing holding onto the bus */	\
89 	MS_SET(VP0_SELTMO),						\
90 /* _loop: */								\
91 	MS_BRCLEAR(0x8, 2 /* _ready */),				\
92 	MS_DBRA(-2 /* _loop */),					\
93 	MS_RET(2),			/* bus busy */			\
94 /* _ready: */								\
95 	MS_CASS(0x4),							\
96 	MS_DASS(MS_UNKNOWN /* 0x80 | 1 << target */),			\
97 	MS_DELAY(1),							\
98 	MS_CASS(0xc),							\
99 	MS_CASS(0xd),							\
100 	/* now, wait until the drive is ready */			\
101 	MS_SET(VP0_SELTMO),						\
102 /* loop: */								\
103 	MS_BRSET(0x8, 3 /* ready */),					\
104 	MS_DBRA(-2 /* loop */),						\
105 /* error: */								\
106 	MS_CASS(0xc),							\
107 	MS_RET(VP0_ESELECT_TIMEOUT),					\
108 /* ready: */								\
109 	MS_CASS(0xc),							\
110 	MS_RET(0)							\
111 }
112 
113 static struct ppb_microseq transfer_epilog[] = {
114 	MS_CASS(0x4),
115 	MS_CASS(0xc),
116 	MS_CASS(0xe),
117 	MS_CASS(0x4),
118 	MS_RET(0)
119 };
120 
121 #define CPP_S1		MS_PARAM(10, 2, MS_TYP_PTR)
122 #define CPP_S2		MS_PARAM(13, 2, MS_TYP_PTR)
123 #define CPP_S3		MS_PARAM(16, 2, MS_TYP_PTR)
124 #define CPP_PARAM	MS_PARAM(17, 1, MS_TYP_CHA)
125 
126 #define DECLARE_CPP_MICROSEQ \
127 struct ppb_microseq cpp_microseq[] = {					\
128 	MS_CASS(0x0c), MS_DELAY(2),					\
129 	MS_DASS(0xaa), MS_DELAY(10),					\
130 	MS_DASS(0x55), MS_DELAY(10),					\
131 	MS_DASS(0x00), MS_DELAY(10),					\
132 	MS_DASS(0xff), MS_DELAY(10),					\
133 	MS_RFETCH(MS_REG_STR, 0xb8, MS_UNKNOWN /* &s1 */),		\
134 	MS_DASS(0x87), MS_DELAY(10),					\
135 	MS_RFETCH(MS_REG_STR, 0xb8, MS_UNKNOWN /* &s2 */),		\
136 	MS_DASS(0x78), MS_DELAY(10),					\
137 	MS_RFETCH(MS_REG_STR, 0x38, MS_UNKNOWN /* &s3 */),		\
138 	MS_DASS(MS_UNKNOWN /* param */),				\
139 	MS_DELAY(2),							\
140 	MS_CASS(0x0c), MS_DELAY(10),					\
141 	MS_CASS(0x0d), MS_DELAY(2),					\
142 	MS_CASS(0x0c), MS_DELAY(10),					\
143 	MS_DASS(0xff), MS_DELAY(10),					\
144 	MS_RET(0)							\
145 }
146 
147 #define NEGOTIATED_MODE		MS_PARAM(2, 1, MS_TYP_CHA)
148 
149 #define DECLARE_NEGOTIATE_MICROSEQ \
150 struct ppb_microseq negotiate_microseq[] = {				\
151 	MS_CASS(0x4),							\
152 	MS_DELAY(5),							\
153 	MS_DASS(MS_UNKNOWN /* mode */),					\
154 	MS_DELAY(100),							\
155 	MS_CASS(0x6),							\
156 	MS_DELAY(5),							\
157 	MS_BRSET(0x20, 5 /* continue */),				\
158 	MS_DELAY(5),							\
159 	MS_CASS(0x7),							\
160 	MS_DELAY(5),							\
161 	MS_CASS(0x6),							\
162 	MS_RET(VP0_ENEGOTIATE),						\
163 /* continue: */								\
164 	MS_DELAY(5),							\
165 	MS_CASS(0x7),							\
166 	MS_DELAY(5),							\
167 	MS_CASS(0x6),							\
168 	MS_RET(0)							\
169 }
170 
171 #define INB_NIBBLE_L MS_PARAM(3, 2, MS_TYP_PTR)
172 #define INB_NIBBLE_H MS_PARAM(6, 2, MS_TYP_PTR)
173 #define INB_NIBBLE_F MS_PARAM(9, 0, MS_TYP_FUN)
174 #define INB_NIBBLE_P MS_PARAM(9, 1, MS_TYP_PTR)
175 
176 /*
177  * This is the sub-microseqence for MS_GET in NIBBLE mode
178  * Retrieve the two nibbles and call the C function to generate the character
179  * and store it in the buffer (see nibble_inbyte_hook())
180  */
181 
182 #define DECLARE_NIBBLE_INBYTE_SUBMICROSEQ \
183 struct ppb_microseq nibble_inbyte_submicroseq[] = {			\
184 	MS_CASS(0x4),							\
185 /* loop: */								\
186 	MS_CASS(0x6),							\
187 	MS_DELAY(1),							\
188 	MS_RFETCH(MS_REG_STR, MS_FETCH_ALL, MS_UNKNOWN /* low nibble */),\
189 	MS_CASS(0x5),							\
190 	MS_DELAY(1),							\
191 	MS_RFETCH(MS_REG_STR, MS_FETCH_ALL, MS_UNKNOWN /* high nibble */),\
192 	MS_CASS(0x4),							\
193 	MS_DELAY(1),							\
194 	/* do a C call to format the received nibbles */		\
195 	MS_C_CALL(MS_UNKNOWN /* C hook */, MS_UNKNOWN /* param */),	\
196 	MS_DBRA(-7 /* loop */),						\
197 	MS_RET(0)							\
198 }
199 
200 static struct ppb_microseq reset_microseq[] = {
201 	MS_CASS(0x04),
202 	MS_DASS(0x40),
203 	MS_DELAY(1),
204 	MS_CASS(0x0c),
205 	MS_CASS(0x0d),
206 	MS_DELAY(50),
207 	MS_CASS(0x0c),
208 	MS_CASS(0x04),
209 	MS_RET(0)
210 };
211 
212 /*
213  * nibble_inbyte_hook()
214  *
215  * Formats high and low nibble into a character
216  */
217 static int
218 nibble_inbyte_hook (void *p, char *ptr)
219 {
220 	struct vpo_nibble *s = (struct vpo_nibble *)p;
221 
222 	/* increment the buffer pointer */
223 	*ptr = ((s->l >> 4) & 0x0f) + (s->h & 0xf0);
224 
225 	return (0);
226 }
227 
228 /*
229  * This is the sub-microseqence for MS_GET in PS2 mode
230  */
231 static struct ppb_microseq ps2_inbyte_submicroseq[] = {
232 	  MS_CASS(0x4),
233 
234 /* loop: */
235 	  MS_CASS(PCD | 0x6),
236 	  MS_RFETCH_P(1, MS_REG_DTR, MS_FETCH_ALL),
237 	  MS_CASS(PCD | 0x5),
238 	  MS_DBRA(-4 /* loop */),
239 
240 	  MS_RET(0)
241 };
242 
243 /*
244  * This is the sub-microsequence for MS_PUT in both NIBBLE and PS2 modes
245  */
246 static struct ppb_microseq spp_outbyte_submicroseq[] = {
247 	  MS_CASS(0x4),
248 
249 /* loop: */
250 	  MS_RASSERT_P(1, MS_REG_DTR),
251 	  MS_CASS(0x5),
252 	  MS_DBRA(0),				/* decrement counter */
253 	  MS_RASSERT_P(1, MS_REG_DTR),
254 	  MS_CASS(0x0),
255 	  MS_DBRA(-6 /* loop */),
256 
257 	  /* return from the put call */
258 	  MS_CASS(0x4),
259 	  MS_RET(0)
260 };
261 
262 /* EPP 1.7 microsequences, ptr and len set at runtime */
263 static struct ppb_microseq epp17_outstr[] = {
264 	  MS_CASS(0x4),
265 	  MS_RASSERT_P(MS_ACCUM, MS_REG_EPP_D),
266 	  MS_CASS(0xc),
267 	  MS_RET(0),
268 };
269 
270 static struct ppb_microseq epp17_instr[] = {
271 	  MS_CASS(PCD | 0x4),
272 	  MS_RFETCH_P(MS_ACCUM, MS_REG_EPP_D, MS_FETCH_ALL),
273 	  MS_CASS(PCD | 0xc),
274 	  MS_RET(0),
275 };
276 
277 static int
278 imm_disconnect(struct vpoio_data *vpo, int *connected, int release_bus)
279 {
280 	DECLARE_CPP_MICROSEQ;
281 
282 	device_t ppbus = device_get_parent(vpo->vpo_dev);
283 	char s1, s2, s3;
284 	int ret;
285 
286 	/* all should be ok */
287 	if (connected)
288 		*connected = 0;
289 
290 	ppb_MS_init_msq(cpp_microseq, 4, CPP_S1, (void *)&s1,
291 			CPP_S2, (void *)&s2, CPP_S3, (void *)&s3,
292 			CPP_PARAM, 0x30);
293 
294 	ppb_MS_microseq(ppbus, vpo->vpo_dev, cpp_microseq, &ret);
295 
296 	if ((s1 != (char)0xb8 || s2 != (char)0x18 || s3 != (char)0x38)) {
297 		if (bootverbose)
298 			kprintf("imm%d: (disconnect) s1=0x%x s2=0x%x, s3=0x%x\n",
299 				vpo->vpo_unit, s1 & 0xff, s2 & 0xff, s3 & 0xff);
300 		if (connected)
301 			*connected = VP0_ECONNECT;
302 	}
303 
304 	if (release_bus)
305 		return (ppb_release_bus(ppbus, vpo->vpo_dev));
306 	else
307 		return (0);
308 }
309 
310 /*
311  * how	: PPB_WAIT or PPB_DONTWAIT
312  */
313 static int
314 imm_connect(struct vpoio_data *vpo, int how, int *disconnected, int request_bus)
315 {
316 	DECLARE_CPP_MICROSEQ;
317 
318 	device_t ppbus = device_get_parent(vpo->vpo_dev);
319 	char s1, s2, s3;
320 	int error;
321 	int ret;
322 
323 	/* all should be ok */
324 	if (disconnected)
325 		*disconnected = 0;
326 
327 	if (request_bus)
328 		if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, how)))
329 			return (error);
330 
331 	ppb_MS_init_msq(cpp_microseq, 3, CPP_S1, (void *)&s1,
332 			CPP_S2, (void *)&s2, CPP_S3, (void *)&s3);
333 
334 	/* select device 0 in compatible mode */
335 	ppb_MS_init_msq(cpp_microseq, 1, CPP_PARAM, 0xe0);
336 	ppb_MS_microseq(ppbus, vpo->vpo_dev, cpp_microseq, &ret);
337 
338 	/* disconnect all devices */
339 	ppb_MS_init_msq(cpp_microseq, 1, CPP_PARAM, 0x30);
340 	ppb_MS_microseq(ppbus, vpo->vpo_dev, cpp_microseq, &ret);
341 
342 	if (PPB_IN_EPP_MODE(ppbus))
343 		ppb_MS_init_msq(cpp_microseq, 1, CPP_PARAM, 0x28);
344 	else
345 		ppb_MS_init_msq(cpp_microseq, 1, CPP_PARAM, 0xe0);
346 
347 	ppb_MS_microseq(ppbus, vpo->vpo_dev, cpp_microseq, &ret);
348 
349 	if ((s1 != (char)0xb8 || s2 != (char)0x18 || s3 != (char)0x30)) {
350 		if (bootverbose)
351 			kprintf("imm%d: (connect) s1=0x%x s2=0x%x, s3=0x%x\n",
352 				vpo->vpo_unit, s1 & 0xff, s2 & 0xff, s3 & 0xff);
353 		if (disconnected)
354 			*disconnected = VP0_ECONNECT;
355 	}
356 
357 	return (0);
358 }
359 
360 /*
361  * imm_detect()
362  *
363  * Detect and initialise the VP0 adapter.
364  */
365 static int
366 imm_detect(struct vpoio_data *vpo)
367 {
368 	device_t ppbus = device_get_parent(vpo->vpo_dev);
369 	int error;
370 
371 	if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, PPB_DONTWAIT)))
372 		return (error);
373 
374 	/* disconnect the drive, keep the bus */
375 	imm_disconnect(vpo, NULL, 0);
376 
377 	vpo->vpo_mode_found = VP0_MODE_UNDEFINED;
378 	error = 1;
379 
380 	/* try to enter EPP mode since vpoio failure put the bus in NIBBLE */
381 	if (ppb_set_mode(ppbus, PPB_EPP) != -1) {
382 		imm_connect(vpo, PPB_DONTWAIT, &error, 0);
383 	}
384 
385 	/* if connection failed try PS/2 then NIBBLE modes */
386 	if (error) {
387 		if (ppb_set_mode(ppbus, PPB_PS2) != -1) {
388 			imm_connect(vpo, PPB_DONTWAIT, &error, 0);
389 		}
390 		if (error) {
391 			if (ppb_set_mode(ppbus, PPB_NIBBLE) != -1) {
392 				imm_connect(vpo, PPB_DONTWAIT, &error, 0);
393 				if (error)
394 					goto error;
395 				vpo->vpo_mode_found = VP0_MODE_NIBBLE;
396 			} else {
397 				kprintf("imm%d: NIBBLE mode unavailable!\n", vpo->vpo_unit);
398 				goto error;
399 			}
400 		} else {
401 			vpo->vpo_mode_found = VP0_MODE_PS2;
402 		}
403 	} else {
404 		vpo->vpo_mode_found = VP0_MODE_EPP;
405 	}
406 
407 	/* send SCSI reset signal */
408 	ppb_MS_microseq(ppbus, vpo->vpo_dev, reset_microseq, NULL);
409 
410 	/* release the bus now */
411 	imm_disconnect(vpo, &error, 1);
412 
413 	/* ensure we are disconnected or daisy chained peripheral
414 	 * may cause serious problem to the disk */
415 
416 	if (error) {
417 		if (bootverbose)
418 			kprintf("imm%d: can't disconnect from the drive\n",
419 				vpo->vpo_unit);
420 		goto error;
421 	}
422 
423 	return (0);
424 
425 error:
426 	ppb_release_bus(ppbus, vpo->vpo_dev);
427 	return (VP0_EINITFAILED);
428 }
429 
430 /*
431  * imm_outstr()
432  */
433 static int
434 imm_outstr(struct vpoio_data *vpo, char *_buffer, int _size)
435 {
436 	union ppb_insarg buffer = { .c = _buffer };
437 	union ppb_insarg size = { .i = _size };
438 	union ppb_insarg unknown = { .i = MS_UNKNOWN };
439 	device_t ppbus = device_get_parent(vpo->vpo_dev);
440 	int error = 0;
441 
442 	if (PPB_IN_EPP_MODE(ppbus))
443 		ppb_reset_epp_timeout(ppbus);
444 
445 	ppb_MS_exec(ppbus, vpo->vpo_dev, MS_OP_PUT, buffer, size, unknown,
446 	    &error);
447 
448 	return (error);
449 }
450 
451 /*
452  * imm_instr()
453  */
454 static int
455 imm_instr(struct vpoio_data *vpo, char *_buffer, int _size)
456 {
457 	union ppb_insarg buffer = { .c = _buffer };
458 	union ppb_insarg size = { .i = _size };
459 	union ppb_insarg unknown = { .i = MS_UNKNOWN };
460 	device_t ppbus = device_get_parent(vpo->vpo_dev);
461 	int error = 0;
462 
463 	if (PPB_IN_EPP_MODE(ppbus))
464 		ppb_reset_epp_timeout(ppbus);
465 
466 	ppb_MS_exec(ppbus, vpo->vpo_dev, MS_OP_GET, buffer, size, unknown,
467 	    &error);
468 
469 	return (error);
470 }
471 
472 static char
473 imm_select(struct vpoio_data *vpo, int initiator, int target)
474 {
475 	DECLARE_SELECT_MICROSEQUENCE;
476 	device_t ppbus = device_get_parent(vpo->vpo_dev);
477 	int ret;
478 
479 	/* initialize the select microsequence */
480 	ppb_MS_init_msq(select_microseq, 1,
481 			SELECT_TARGET, 1 << initiator | 1 << target);
482 
483 	ppb_MS_microseq(ppbus, vpo->vpo_dev, select_microseq, &ret);
484 
485 	return (ret);
486 }
487 
488 /*
489  * imm_wait()
490  *
491  * H_SELIN must be low.
492  *
493  */
494 static char
495 imm_wait(struct vpoio_data *vpo, int tmo)
496 {
497 	DECLARE_WAIT_MICROSEQUENCE;
498 
499 	device_t ppbus = device_get_parent(vpo->vpo_dev);
500 	int ret, err;
501 
502 	/*
503 	 * Return some status information.
504 	 * Semantics :	0x88 = ZIP+ wants more data
505 	 *		0x98 = ZIP+ wants to send more data
506 	 *		0xa8 = ZIP+ wants command
507 	 *		0xb8 = end of transfer, ZIP+ is sending status
508 	 */
509 
510 	ppb_MS_init_msq(wait_microseq, 2,
511 			WAIT_RET, (void *)&ret,
512 			WAIT_TMO, tmo);
513 
514 	ppb_MS_microseq(ppbus, vpo->vpo_dev, wait_microseq, &err);
515 
516 	if (err)
517 		return (0);			   /* command timed out */
518 
519 	return(ret);
520 }
521 
522 static int
523 imm_negotiate(struct vpoio_data *vpo)
524 {
525 	DECLARE_NEGOTIATE_MICROSEQ;
526 	device_t ppbus = device_get_parent(vpo->vpo_dev);
527 	int negotiate_mode;
528 	int ret;
529 
530 	if (PPB_IN_NIBBLE_MODE(ppbus))
531 		negotiate_mode = 0;
532 	else if (PPB_IN_PS2_MODE(ppbus))
533 		negotiate_mode = 1;
534 	else
535 		return (0);
536 
537 #if 0 /* XXX use standalone code not to depend on ppb_1284 code yet */
538 	ret = ppb_1284_negotiate(ppbus, negotiate_mode);
539 
540 	if (ret)
541 		return (VP0_ENEGOTIATE);
542 #endif
543 
544 	ppb_MS_init_msq(negotiate_microseq, 1,
545 			NEGOTIATED_MODE, negotiate_mode);
546 
547 	ppb_MS_microseq(ppbus, vpo->vpo_dev, negotiate_microseq, &ret);
548 
549 	return (ret);
550 }
551 
552 /*
553  * imm_probe()
554  *
555  * Low level probe of vpo device
556  *
557  */
558 int
559 imm_probe(device_t dev, struct vpoio_data *vpo)
560 {
561 	int error;
562 
563 	/* ppbus dependent initialisation */
564 	vpo->vpo_dev = dev;
565 
566 	/* now, try to initialise the drive */
567 	if ((error = imm_detect(vpo))) {
568 		return (error);
569 	}
570 
571 	return (0);
572 }
573 
574 /*
575  * imm_attach()
576  *
577  * Low level attachment of vpo device
578  *
579  */
580 int
581 imm_attach(struct vpoio_data *vpo)
582 {
583 	DECLARE_NIBBLE_INBYTE_SUBMICROSEQ;
584 	device_t ppbus = device_get_parent(vpo->vpo_dev);
585 	int error = 0;
586 
587 	/*
588 	 * Initialize microsequence code
589 	 */
590 	vpo->vpo_nibble_inbyte_msq = kmalloc(sizeof(nibble_inbyte_submicroseq),
591 						M_DEVBUF, M_WAITOK);
592 
593 	bcopy((void *)nibble_inbyte_submicroseq,
594 		(void *)vpo->vpo_nibble_inbyte_msq,
595 		sizeof(nibble_inbyte_submicroseq));
596 
597 	ppb_MS_init_msq(vpo->vpo_nibble_inbyte_msq, 4,
598 		INB_NIBBLE_H, (void *)&(vpo)->vpo_nibble.h,
599 		INB_NIBBLE_L, (void *)&(vpo)->vpo_nibble.l,
600 		INB_NIBBLE_F, nibble_inbyte_hook,
601 		INB_NIBBLE_P, (void *)&(vpo)->vpo_nibble);
602 
603 	/*
604 	 * Initialize mode dependent in/out microsequences
605 	 */
606 	if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, PPB_WAIT)))
607 	    goto error;
608 
609 	/* ppbus automatically restore the last mode entered during detection */
610 	switch (vpo->vpo_mode_found) {
611 	case VP0_MODE_EPP:
612 		ppb_MS_GET_init(ppbus, vpo->vpo_dev, epp17_instr);
613 		ppb_MS_PUT_init(ppbus, vpo->vpo_dev, epp17_outstr);
614 		kprintf("imm%d: EPP mode\n", vpo->vpo_unit);
615 		break;
616 	case VP0_MODE_PS2:
617 		ppb_MS_GET_init(ppbus, vpo->vpo_dev, ps2_inbyte_submicroseq);
618 		ppb_MS_PUT_init(ppbus, vpo->vpo_dev, spp_outbyte_submicroseq);
619 		kprintf("imm%d: PS2 mode\n", vpo->vpo_unit);
620 		break;
621 	case VP0_MODE_NIBBLE:
622 		ppb_MS_GET_init(ppbus, vpo->vpo_dev, vpo->vpo_nibble_inbyte_msq);
623 		ppb_MS_PUT_init(ppbus, vpo->vpo_dev, spp_outbyte_submicroseq);
624 		kprintf("imm%d: NIBBLE mode\n", vpo->vpo_unit);
625 		break;
626 	default:
627 		panic("imm: unknown mode %d", vpo->vpo_mode_found);
628 	}
629 
630 	ppb_release_bus(ppbus, vpo->vpo_dev);
631  error:
632 	return (error);
633 }
634 
635 /*
636  * imm_reset_bus()
637  *
638  */
639 int
640 imm_reset_bus(struct vpoio_data *vpo)
641 {
642 	device_t ppbus = device_get_parent(vpo->vpo_dev);
643 	int disconnected;
644 
645 	/* first, connect to the drive and request the bus */
646 	imm_connect(vpo, PPB_WAIT|PPB_INTR, &disconnected, 1);
647 
648 	if (!disconnected) {
649 
650 		/* reset the SCSI bus */
651 		ppb_MS_microseq(ppbus, vpo->vpo_dev, reset_microseq, NULL);
652 
653 		/* then disconnect */
654 		imm_disconnect(vpo, NULL, 1);
655 	}
656 
657 	return (0);
658 }
659 
660 /*
661  * imm_do_scsi()
662  *
663  * Send an SCSI command
664  *
665  */
666 int
667 imm_do_scsi(struct vpoio_data *vpo, int host, int target, char *command,
668 		int clen, char *buffer, int blen, int *result, int *count,
669 		int *ret)
670 {
671 	device_t ppbus = device_get_parent(vpo->vpo_dev);
672 	char r;
673 	char l, h = 0;
674 	int len, error = 0, not_connected = 0;
675 	int k;
676 	int negotiated = 0;
677 
678 	/*
679 	 * enter disk state, allocate the ppbus
680 	 *
681 	 * XXX
682 	 * Should we allow this call to be interruptible?
683 	 * The only way to report the interruption is to return
684 	 * EIO to upper SCSI code :^(
685 	 */
686 	if ((error = imm_connect(vpo, PPB_WAIT|PPB_INTR, &not_connected, 1)))
687 		return (error);
688 
689 	if (not_connected) {
690 		*ret = VP0_ECONNECT; goto error;
691 	}
692 
693 	/*
694 	 * Select the drive ...
695 	 */
696 	if ((*ret = imm_select(vpo,host,target)))
697 		goto error;
698 
699 	/*
700 	 * Send the command ...
701 	 */
702 	for (k = 0; k < clen; k+=2) {
703 		if (imm_wait(vpo, VP0_FAST_SPINTMO) != (char)0xa8) {
704 			*ret = VP0_ECMD_TIMEOUT;
705 			goto error;
706 		}
707 		if (imm_outstr(vpo, &command[k], 2)) {
708 			*ret = VP0_EPPDATA_TIMEOUT;
709 			goto error;
710 		}
711 	}
712 
713 	if (!(r = imm_wait(vpo, VP0_LOW_SPINTMO))) {
714 		*ret = VP0_ESTATUS_TIMEOUT; goto error;
715 	}
716 
717 	if ((r & 0x30) == 0x10) {
718 		if (imm_negotiate(vpo)) {
719 			*ret = VP0_ENEGOTIATE;
720 			goto error;
721 		} else
722 			negotiated = 1;
723 	}
724 
725 	/*
726 	 * Complete transfer ...
727 	 */
728 	*count = 0;
729 	for (;;) {
730 
731 		if (!(r = imm_wait(vpo, VP0_LOW_SPINTMO))) {
732 			*ret = VP0_ESTATUS_TIMEOUT; goto error;
733 		}
734 
735 		/* stop when the ZIP+ wants to send status */
736 		if (r == (char)0xb8)
737 			break;
738 
739 		if (*count >= blen) {
740 			*ret = VP0_EDATA_OVERFLOW;
741 			goto error;
742 		}
743 
744 		/* ZIP+ wants to send data? */
745 		if (r == (char)0x88) {
746 			len = (((blen - *count) >= VP0_SECTOR_SIZE)) ?
747 				VP0_SECTOR_SIZE : 2;
748 
749 			error = imm_outstr(vpo, &buffer[*count], len);
750 		} else {
751 			if (!PPB_IN_EPP_MODE(ppbus))
752 				len = 1;
753 			else
754 				len = (((blen - *count) >= VP0_SECTOR_SIZE)) ?
755 					VP0_SECTOR_SIZE : 1;
756 
757 			error = imm_instr(vpo, &buffer[*count], len);
758 		}
759 
760 		if (error) {
761 			*ret = error;
762 			goto error;
763 		}
764 
765 		*count += len;
766 	}
767 
768 	if ((PPB_IN_NIBBLE_MODE(ppbus) ||
769 			PPB_IN_PS2_MODE(ppbus)) && negotiated)
770 		ppb_MS_microseq(ppbus, vpo->vpo_dev, transfer_epilog, NULL);
771 
772 	/*
773 	 * Retrieve status ...
774 	 */
775 	if (imm_negotiate(vpo)) {
776 		*ret = VP0_ENEGOTIATE;
777 		goto error;
778 	} else
779 		negotiated = 1;
780 
781 	if (imm_instr(vpo, &l, 1)) {
782 		*ret = VP0_EOTHER; goto error;
783 	}
784 
785 	/* check if the ZIP+ wants to send more status */
786 	if (imm_wait(vpo, VP0_FAST_SPINTMO) == (char)0xb8)
787 		if (imm_instr(vpo, &h, 1)) {
788 			*ret = VP0_EOTHER+2; goto error;
789 		}
790 
791 	/* Experience showed that we should discard this */
792 	if (h == -1)
793 		h = 0;
794 
795 	*result = ((int) h << 8) | ((int) l & 0xff);
796 
797 error:
798 	if ((PPB_IN_NIBBLE_MODE(ppbus) ||
799 			PPB_IN_PS2_MODE(ppbus)) && negotiated)
800 		ppb_MS_microseq(ppbus, vpo->vpo_dev, transfer_epilog, NULL);
801 
802 	/* return to printer state, release the ppbus */
803 	imm_disconnect(vpo, NULL, 1);
804 
805 	return (0);
806 }
807