1 /*
2  *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
3  *
4  *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
5  *  Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 #include <linux/ctype.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/workqueue.h>
25 #include <linux/blkdev.h>
26 #include <linux/mutex.h>
27 #include <linux/sysfs.h>
28 #include <linux/slab.h>
29 #include <linux/suspend.h>
30 #include <scsi/scsi.h>
31 #include "scsi_priv.h"
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi_cmnd.h>
35 #include <scsi/scsi_eh.h>
36 #include <scsi/scsi_tcq.h>
37 #include <scsi/scsi_transport.h>
38 #include <scsi/scsi_transport_spi.h>
39 
40 #define SPI_NUM_ATTRS 14	/* increase this if you add attributes */
41 #define SPI_OTHER_ATTRS 1	/* Increase this if you add "always
42 				 * on" attributes */
43 #define SPI_HOST_ATTRS	1
44 
45 #define SPI_MAX_ECHO_BUFFER_SIZE	4096
46 
47 #define DV_LOOPS	3
48 #define DV_TIMEOUT	(10*HZ)
49 #define DV_RETRIES	3	/* should only need at most
50 				 * two cc/ua clears */
51 
52 /* Our blacklist flags */
53 enum {
54 	SPI_BLIST_NOIUS = (__force blist_flags_t)0x1,
55 };
56 
57 /* blacklist table, modelled on scsi_devinfo.c */
58 static struct {
59 	char *vendor;
60 	char *model;
61 	blist_flags_t flags;
62 } spi_static_device_list[] __initdata = {
63 	{"HP", "Ultrium 3-SCSI", SPI_BLIST_NOIUS },
64 	{"IBM", "ULTRIUM-TD3", SPI_BLIST_NOIUS },
65 	{NULL, NULL, 0}
66 };
67 
68 /* Private data accessors (keep these out of the header file) */
69 #define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
70 #define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
71 
72 struct spi_internal {
73 	struct scsi_transport_template t;
74 	struct spi_function_template *f;
75 };
76 
77 #define to_spi_internal(tmpl)	container_of(tmpl, struct spi_internal, t)
78 
79 static const int ppr_to_ps[] = {
80 	/* The PPR values 0-6 are reserved, fill them in when
81 	 * the committee defines them */
82 	-1,			/* 0x00 */
83 	-1,			/* 0x01 */
84 	-1,			/* 0x02 */
85 	-1,			/* 0x03 */
86 	-1,			/* 0x04 */
87 	-1,			/* 0x05 */
88 	-1,			/* 0x06 */
89 	 3125,			/* 0x07 */
90 	 6250,			/* 0x08 */
91 	12500,			/* 0x09 */
92 	25000,			/* 0x0a */
93 	30300,			/* 0x0b */
94 	50000,			/* 0x0c */
95 };
96 /* The PPR values at which you calculate the period in ns by multiplying
97  * by 4 */
98 #define SPI_STATIC_PPR	0x0c
99 
100 static int sprint_frac(char *dest, int value, int denom)
101 {
102 	int frac = value % denom;
103 	int result = sprintf(dest, "%d", value / denom);
104 
105 	if (frac == 0)
106 		return result;
107 	dest[result++] = '.';
108 
109 	do {
110 		denom /= 10;
111 		sprintf(dest + result, "%d", frac / denom);
112 		result++;
113 		frac %= denom;
114 	} while (frac);
115 
116 	dest[result++] = '\0';
117 	return result;
118 }
119 
120 static int spi_execute(struct scsi_device *sdev, const void *cmd,
121 		       enum dma_data_direction dir,
122 		       void *buffer, unsigned bufflen,
123 		       struct scsi_sense_hdr *sshdr)
124 {
125 	int i, result;
126 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
127 	struct scsi_sense_hdr sshdr_tmp;
128 
129 	if (!sshdr)
130 		sshdr = &sshdr_tmp;
131 
132 	for(i = 0; i < DV_RETRIES; i++) {
133 		result = scsi_execute(sdev, cmd, dir, buffer, bufflen, sense,
134 				      sshdr, DV_TIMEOUT, /* retries */ 1,
135 				      REQ_FAILFAST_DEV |
136 				      REQ_FAILFAST_TRANSPORT |
137 				      REQ_FAILFAST_DRIVER,
138 				      0, NULL);
139 		if (!(driver_byte(result) & DRIVER_SENSE) ||
140 		    sshdr->sense_key != UNIT_ATTENTION)
141 			break;
142 	}
143 	return result;
144 }
145 
146 static struct {
147 	enum spi_signal_type	value;
148 	char			*name;
149 } signal_types[] = {
150 	{ SPI_SIGNAL_UNKNOWN, "unknown" },
151 	{ SPI_SIGNAL_SE, "SE" },
152 	{ SPI_SIGNAL_LVD, "LVD" },
153 	{ SPI_SIGNAL_HVD, "HVD" },
154 };
155 
156 static inline const char *spi_signal_to_string(enum spi_signal_type type)
157 {
158 	int i;
159 
160 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
161 		if (type == signal_types[i].value)
162 			return signal_types[i].name;
163 	}
164 	return NULL;
165 }
166 static inline enum spi_signal_type spi_signal_to_value(const char *name)
167 {
168 	int i, len;
169 
170 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
171 		len =  strlen(signal_types[i].name);
172 		if (strncmp(name, signal_types[i].name, len) == 0 &&
173 		    (name[len] == '\n' || name[len] == '\0'))
174 			return signal_types[i].value;
175 	}
176 	return SPI_SIGNAL_UNKNOWN;
177 }
178 
179 static int spi_host_setup(struct transport_container *tc, struct device *dev,
180 			  struct device *cdev)
181 {
182 	struct Scsi_Host *shost = dev_to_shost(dev);
183 
184 	spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
185 
186 	return 0;
187 }
188 
189 static int spi_host_configure(struct transport_container *tc,
190 			      struct device *dev,
191 			      struct device *cdev);
192 
193 static DECLARE_TRANSPORT_CLASS(spi_host_class,
194 			       "spi_host",
195 			       spi_host_setup,
196 			       NULL,
197 			       spi_host_configure);
198 
199 static int spi_host_match(struct attribute_container *cont,
200 			  struct device *dev)
201 {
202 	struct Scsi_Host *shost;
203 
204 	if (!scsi_is_host_device(dev))
205 		return 0;
206 
207 	shost = dev_to_shost(dev);
208 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
209 	    != &spi_host_class.class)
210 		return 0;
211 
212 	return &shost->transportt->host_attrs.ac == cont;
213 }
214 
215 static int spi_target_configure(struct transport_container *tc,
216 				struct device *dev,
217 				struct device *cdev);
218 
219 static int spi_device_configure(struct transport_container *tc,
220 				struct device *dev,
221 				struct device *cdev)
222 {
223 	struct scsi_device *sdev = to_scsi_device(dev);
224 	struct scsi_target *starget = sdev->sdev_target;
225 	blist_flags_t bflags;
226 
227 	bflags = scsi_get_device_flags_keyed(sdev, &sdev->inquiry[8],
228 					     &sdev->inquiry[16],
229 					     SCSI_DEVINFO_SPI);
230 
231 	/* Populate the target capability fields with the values
232 	 * gleaned from the device inquiry */
233 
234 	spi_support_sync(starget) = scsi_device_sync(sdev);
235 	spi_support_wide(starget) = scsi_device_wide(sdev);
236 	spi_support_dt(starget) = scsi_device_dt(sdev);
237 	spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
238 	spi_support_ius(starget) = scsi_device_ius(sdev);
239 	if (bflags & SPI_BLIST_NOIUS) {
240 		dev_info(dev, "Information Units disabled by blacklist\n");
241 		spi_support_ius(starget) = 0;
242 	}
243 	spi_support_qas(starget) = scsi_device_qas(sdev);
244 
245 	return 0;
246 }
247 
248 static int spi_setup_transport_attrs(struct transport_container *tc,
249 				     struct device *dev,
250 				     struct device *cdev)
251 {
252 	struct scsi_target *starget = to_scsi_target(dev);
253 
254 	spi_period(starget) = -1;	/* illegal value */
255 	spi_min_period(starget) = 0;
256 	spi_offset(starget) = 0;	/* async */
257 	spi_max_offset(starget) = 255;
258 	spi_width(starget) = 0;	/* narrow */
259 	spi_max_width(starget) = 1;
260 	spi_iu(starget) = 0;	/* no IU */
261 	spi_max_iu(starget) = 1;
262 	spi_dt(starget) = 0;	/* ST */
263 	spi_qas(starget) = 0;
264 	spi_max_qas(starget) = 1;
265 	spi_wr_flow(starget) = 0;
266 	spi_rd_strm(starget) = 0;
267 	spi_rti(starget) = 0;
268 	spi_pcomp_en(starget) = 0;
269 	spi_hold_mcs(starget) = 0;
270 	spi_dv_pending(starget) = 0;
271 	spi_dv_in_progress(starget) = 0;
272 	spi_initial_dv(starget) = 0;
273 	mutex_init(&spi_dv_mutex(starget));
274 
275 	return 0;
276 }
277 
278 #define spi_transport_show_simple(field, format_string)			\
279 									\
280 static ssize_t								\
281 show_spi_transport_##field(struct device *dev, 			\
282 			   struct device_attribute *attr, char *buf)	\
283 {									\
284 	struct scsi_target *starget = transport_class_to_starget(dev);	\
285 	struct spi_transport_attrs *tp;					\
286 									\
287 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
288 	return snprintf(buf, 20, format_string, tp->field);		\
289 }
290 
291 #define spi_transport_store_simple(field, format_string)		\
292 									\
293 static ssize_t								\
294 store_spi_transport_##field(struct device *dev, 			\
295 			    struct device_attribute *attr, 		\
296 			    const char *buf, size_t count)		\
297 {									\
298 	int val;							\
299 	struct scsi_target *starget = transport_class_to_starget(dev);	\
300 	struct spi_transport_attrs *tp;					\
301 									\
302 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
303 	val = simple_strtoul(buf, NULL, 0);				\
304 	tp->field = val;						\
305 	return count;							\
306 }
307 
308 #define spi_transport_show_function(field, format_string)		\
309 									\
310 static ssize_t								\
311 show_spi_transport_##field(struct device *dev, 			\
312 			   struct device_attribute *attr, char *buf)	\
313 {									\
314 	struct scsi_target *starget = transport_class_to_starget(dev);	\
315 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
316 	struct spi_transport_attrs *tp;					\
317 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
318 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
319 	if (i->f->get_##field)						\
320 		i->f->get_##field(starget);				\
321 	return snprintf(buf, 20, format_string, tp->field);		\
322 }
323 
324 #define spi_transport_store_function(field, format_string)		\
325 static ssize_t								\
326 store_spi_transport_##field(struct device *dev, 			\
327 			    struct device_attribute *attr,		\
328 			    const char *buf, size_t count)		\
329 {									\
330 	int val;							\
331 	struct scsi_target *starget = transport_class_to_starget(dev);	\
332 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
333 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
334 									\
335 	if (!i->f->set_##field)						\
336 		return -EINVAL;						\
337 	val = simple_strtoul(buf, NULL, 0);				\
338 	i->f->set_##field(starget, val);				\
339 	return count;							\
340 }
341 
342 #define spi_transport_store_max(field, format_string)			\
343 static ssize_t								\
344 store_spi_transport_##field(struct device *dev, 			\
345 			    struct device_attribute *attr,		\
346 			    const char *buf, size_t count)		\
347 {									\
348 	int val;							\
349 	struct scsi_target *starget = transport_class_to_starget(dev);	\
350 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
351 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
352 	struct spi_transport_attrs *tp					\
353 		= (struct spi_transport_attrs *)&starget->starget_data;	\
354 									\
355 	if (i->f->set_##field)						\
356 		return -EINVAL;						\
357 	val = simple_strtoul(buf, NULL, 0);				\
358 	if (val > tp->max_##field)					\
359 		val = tp->max_##field;					\
360 	i->f->set_##field(starget, val);				\
361 	return count;							\
362 }
363 
364 #define spi_transport_rd_attr(field, format_string)			\
365 	spi_transport_show_function(field, format_string)		\
366 	spi_transport_store_function(field, format_string)		\
367 static DEVICE_ATTR(field, S_IRUGO,				\
368 		   show_spi_transport_##field,			\
369 		   store_spi_transport_##field);
370 
371 #define spi_transport_simple_attr(field, format_string)			\
372 	spi_transport_show_simple(field, format_string)			\
373 	spi_transport_store_simple(field, format_string)		\
374 static DEVICE_ATTR(field, S_IRUGO,				\
375 		   show_spi_transport_##field,			\
376 		   store_spi_transport_##field);
377 
378 #define spi_transport_max_attr(field, format_string)			\
379 	spi_transport_show_function(field, format_string)		\
380 	spi_transport_store_max(field, format_string)			\
381 	spi_transport_simple_attr(max_##field, format_string)		\
382 static DEVICE_ATTR(field, S_IRUGO,				\
383 		   show_spi_transport_##field,			\
384 		   store_spi_transport_##field);
385 
386 /* The Parallel SCSI Tranport Attributes: */
387 spi_transport_max_attr(offset, "%d\n");
388 spi_transport_max_attr(width, "%d\n");
389 spi_transport_max_attr(iu, "%d\n");
390 spi_transport_rd_attr(dt, "%d\n");
391 spi_transport_max_attr(qas, "%d\n");
392 spi_transport_rd_attr(wr_flow, "%d\n");
393 spi_transport_rd_attr(rd_strm, "%d\n");
394 spi_transport_rd_attr(rti, "%d\n");
395 spi_transport_rd_attr(pcomp_en, "%d\n");
396 spi_transport_rd_attr(hold_mcs, "%d\n");
397 
398 /* we only care about the first child device that's a real SCSI device
399  * so we return 1 to terminate the iteration when we find it */
400 static int child_iter(struct device *dev, void *data)
401 {
402 	if (!scsi_is_sdev_device(dev))
403 		return 0;
404 
405 	spi_dv_device(to_scsi_device(dev));
406 	return 1;
407 }
408 
409 static ssize_t
410 store_spi_revalidate(struct device *dev, struct device_attribute *attr,
411 		     const char *buf, size_t count)
412 {
413 	struct scsi_target *starget = transport_class_to_starget(dev);
414 
415 	device_for_each_child(&starget->dev, NULL, child_iter);
416 	return count;
417 }
418 static DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
419 
420 /* Translate the period into ns according to the current spec
421  * for SDTR/PPR messages */
422 static int period_to_str(char *buf, int period)
423 {
424 	int len, picosec;
425 
426 	if (period < 0 || period > 0xff) {
427 		picosec = -1;
428 	} else if (period <= SPI_STATIC_PPR) {
429 		picosec = ppr_to_ps[period];
430 	} else {
431 		picosec = period * 4000;
432 	}
433 
434 	if (picosec == -1) {
435 		len = sprintf(buf, "reserved");
436 	} else {
437 		len = sprint_frac(buf, picosec, 1000);
438 	}
439 
440 	return len;
441 }
442 
443 static ssize_t
444 show_spi_transport_period_helper(char *buf, int period)
445 {
446 	int len = period_to_str(buf, period);
447 	buf[len++] = '\n';
448 	buf[len] = '\0';
449 	return len;
450 }
451 
452 static ssize_t
453 store_spi_transport_period_helper(struct device *dev, const char *buf,
454 				  size_t count, int *periodp)
455 {
456 	int j, picosec, period = -1;
457 	char *endp;
458 
459 	picosec = simple_strtoul(buf, &endp, 10) * 1000;
460 	if (*endp == '.') {
461 		int mult = 100;
462 		do {
463 			endp++;
464 			if (!isdigit(*endp))
465 				break;
466 			picosec += (*endp - '0') * mult;
467 			mult /= 10;
468 		} while (mult > 0);
469 	}
470 
471 	for (j = 0; j <= SPI_STATIC_PPR; j++) {
472 		if (ppr_to_ps[j] < picosec)
473 			continue;
474 		period = j;
475 		break;
476 	}
477 
478 	if (period == -1)
479 		period = picosec / 4000;
480 
481 	if (period > 0xff)
482 		period = 0xff;
483 
484 	*periodp = period;
485 
486 	return count;
487 }
488 
489 static ssize_t
490 show_spi_transport_period(struct device *dev,
491 			  struct device_attribute *attr, char *buf)
492 {
493 	struct scsi_target *starget = transport_class_to_starget(dev);
494 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
495 	struct spi_internal *i = to_spi_internal(shost->transportt);
496 	struct spi_transport_attrs *tp =
497 		(struct spi_transport_attrs *)&starget->starget_data;
498 
499 	if (i->f->get_period)
500 		i->f->get_period(starget);
501 
502 	return show_spi_transport_period_helper(buf, tp->period);
503 }
504 
505 static ssize_t
506 store_spi_transport_period(struct device *cdev, struct device_attribute *attr,
507 			   const char *buf, size_t count)
508 {
509 	struct scsi_target *starget = transport_class_to_starget(cdev);
510 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
511 	struct spi_internal *i = to_spi_internal(shost->transportt);
512 	struct spi_transport_attrs *tp =
513 		(struct spi_transport_attrs *)&starget->starget_data;
514 	int period, retval;
515 
516 	if (!i->f->set_period)
517 		return -EINVAL;
518 
519 	retval = store_spi_transport_period_helper(cdev, buf, count, &period);
520 
521 	if (period < tp->min_period)
522 		period = tp->min_period;
523 
524 	i->f->set_period(starget, period);
525 
526 	return retval;
527 }
528 
529 static DEVICE_ATTR(period, S_IRUGO,
530 		   show_spi_transport_period,
531 		   store_spi_transport_period);
532 
533 static ssize_t
534 show_spi_transport_min_period(struct device *cdev,
535 			      struct device_attribute *attr, char *buf)
536 {
537 	struct scsi_target *starget = transport_class_to_starget(cdev);
538 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
539 	struct spi_internal *i = to_spi_internal(shost->transportt);
540 	struct spi_transport_attrs *tp =
541 		(struct spi_transport_attrs *)&starget->starget_data;
542 
543 	if (!i->f->set_period)
544 		return -EINVAL;
545 
546 	return show_spi_transport_period_helper(buf, tp->min_period);
547 }
548 
549 static ssize_t
550 store_spi_transport_min_period(struct device *cdev,
551 			       struct device_attribute *attr,
552 			       const char *buf, size_t count)
553 {
554 	struct scsi_target *starget = transport_class_to_starget(cdev);
555 	struct spi_transport_attrs *tp =
556 		(struct spi_transport_attrs *)&starget->starget_data;
557 
558 	return store_spi_transport_period_helper(cdev, buf, count,
559 						 &tp->min_period);
560 }
561 
562 
563 static DEVICE_ATTR(min_period, S_IRUGO,
564 		   show_spi_transport_min_period,
565 		   store_spi_transport_min_period);
566 
567 
568 static ssize_t show_spi_host_signalling(struct device *cdev,
569 					struct device_attribute *attr,
570 					char *buf)
571 {
572 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
573 	struct spi_internal *i = to_spi_internal(shost->transportt);
574 
575 	if (i->f->get_signalling)
576 		i->f->get_signalling(shost);
577 
578 	return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
579 }
580 static ssize_t store_spi_host_signalling(struct device *dev,
581 					 struct device_attribute *attr,
582 					 const char *buf, size_t count)
583 {
584 	struct Scsi_Host *shost = transport_class_to_shost(dev);
585 	struct spi_internal *i = to_spi_internal(shost->transportt);
586 	enum spi_signal_type type = spi_signal_to_value(buf);
587 
588 	if (!i->f->set_signalling)
589 		return -EINVAL;
590 
591 	if (type != SPI_SIGNAL_UNKNOWN)
592 		i->f->set_signalling(shost, type);
593 
594 	return count;
595 }
596 static DEVICE_ATTR(signalling, S_IRUGO,
597 		   show_spi_host_signalling,
598 		   store_spi_host_signalling);
599 
600 static ssize_t show_spi_host_width(struct device *cdev,
601 				      struct device_attribute *attr,
602 				      char *buf)
603 {
604 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
605 
606 	return sprintf(buf, "%s\n", shost->max_id == 16 ? "wide" : "narrow");
607 }
608 static DEVICE_ATTR(host_width, S_IRUGO,
609 		   show_spi_host_width, NULL);
610 
611 static ssize_t show_spi_host_hba_id(struct device *cdev,
612 				    struct device_attribute *attr,
613 				    char *buf)
614 {
615 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
616 
617 	return sprintf(buf, "%d\n", shost->this_id);
618 }
619 static DEVICE_ATTR(hba_id, S_IRUGO,
620 		   show_spi_host_hba_id, NULL);
621 
622 #define DV_SET(x, y)			\
623 	if(i->f->set_##x)		\
624 		i->f->set_##x(sdev->sdev_target, y)
625 
626 enum spi_compare_returns {
627 	SPI_COMPARE_SUCCESS,
628 	SPI_COMPARE_FAILURE,
629 	SPI_COMPARE_SKIP_TEST,
630 };
631 
632 
633 /* This is for read/write Domain Validation:  If the device supports
634  * an echo buffer, we do read/write tests to it */
635 static enum spi_compare_returns
636 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
637 			  u8 *ptr, const int retries)
638 {
639 	int len = ptr - buffer;
640 	int j, k, r, result;
641 	unsigned int pattern = 0x0000ffff;
642 	struct scsi_sense_hdr sshdr;
643 
644 	const char spi_write_buffer[] = {
645 		WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
646 	};
647 	const char spi_read_buffer[] = {
648 		READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
649 	};
650 
651 	/* set up the pattern buffer.  Doesn't matter if we spill
652 	 * slightly beyond since that's where the read buffer is */
653 	for (j = 0; j < len; ) {
654 
655 		/* fill the buffer with counting (test a) */
656 		for ( ; j < min(len, 32); j++)
657 			buffer[j] = j;
658 		k = j;
659 		/* fill the buffer with alternating words of 0x0 and
660 		 * 0xffff (test b) */
661 		for ( ; j < min(len, k + 32); j += 2) {
662 			u16 *word = (u16 *)&buffer[j];
663 
664 			*word = (j & 0x02) ? 0x0000 : 0xffff;
665 		}
666 		k = j;
667 		/* fill with crosstalk (alternating 0x5555 0xaaa)
668                  * (test c) */
669 		for ( ; j < min(len, k + 32); j += 2) {
670 			u16 *word = (u16 *)&buffer[j];
671 
672 			*word = (j & 0x02) ? 0x5555 : 0xaaaa;
673 		}
674 		k = j;
675 		/* fill with shifting bits (test d) */
676 		for ( ; j < min(len, k + 32); j += 4) {
677 			u32 *word = (unsigned int *)&buffer[j];
678 			u32 roll = (pattern & 0x80000000) ? 1 : 0;
679 
680 			*word = pattern;
681 			pattern = (pattern << 1) | roll;
682 		}
683 		/* don't bother with random data (test e) */
684 	}
685 
686 	for (r = 0; r < retries; r++) {
687 		result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
688 				     buffer, len, &sshdr);
689 		if(result || !scsi_device_online(sdev)) {
690 
691 			scsi_device_set_state(sdev, SDEV_QUIESCE);
692 			if (scsi_sense_valid(&sshdr)
693 			    && sshdr.sense_key == ILLEGAL_REQUEST
694 			    /* INVALID FIELD IN CDB */
695 			    && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
696 				/* This would mean that the drive lied
697 				 * to us about supporting an echo
698 				 * buffer (unfortunately some Western
699 				 * Digital drives do precisely this)
700 				 */
701 				return SPI_COMPARE_SKIP_TEST;
702 
703 
704 			sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
705 			return SPI_COMPARE_FAILURE;
706 		}
707 
708 		memset(ptr, 0, len);
709 		spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
710 			    ptr, len, NULL);
711 		scsi_device_set_state(sdev, SDEV_QUIESCE);
712 
713 		if (memcmp(buffer, ptr, len) != 0)
714 			return SPI_COMPARE_FAILURE;
715 	}
716 	return SPI_COMPARE_SUCCESS;
717 }
718 
719 /* This is for the simplest form of Domain Validation: a read test
720  * on the inquiry data from the device */
721 static enum spi_compare_returns
722 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
723 			      u8 *ptr, const int retries)
724 {
725 	int r, result;
726 	const int len = sdev->inquiry_len;
727 	const char spi_inquiry[] = {
728 		INQUIRY, 0, 0, 0, len, 0
729 	};
730 
731 	for (r = 0; r < retries; r++) {
732 		memset(ptr, 0, len);
733 
734 		result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
735 				     ptr, len, NULL);
736 
737 		if(result || !scsi_device_online(sdev)) {
738 			scsi_device_set_state(sdev, SDEV_QUIESCE);
739 			return SPI_COMPARE_FAILURE;
740 		}
741 
742 		/* If we don't have the inquiry data already, the
743 		 * first read gets it */
744 		if (ptr == buffer) {
745 			ptr += len;
746 			--r;
747 			continue;
748 		}
749 
750 		if (memcmp(buffer, ptr, len) != 0)
751 			/* failure */
752 			return SPI_COMPARE_FAILURE;
753 	}
754 	return SPI_COMPARE_SUCCESS;
755 }
756 
757 static enum spi_compare_returns
758 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
759 	       enum spi_compare_returns
760 	       (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
761 {
762 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
763 	struct scsi_target *starget = sdev->sdev_target;
764 	int period = 0, prevperiod = 0;
765 	enum spi_compare_returns retval;
766 
767 
768 	for (;;) {
769 		int newperiod;
770 		retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
771 
772 		if (retval == SPI_COMPARE_SUCCESS
773 		    || retval == SPI_COMPARE_SKIP_TEST)
774 			break;
775 
776 		/* OK, retrain, fallback */
777 		if (i->f->get_iu)
778 			i->f->get_iu(starget);
779 		if (i->f->get_qas)
780 			i->f->get_qas(starget);
781 		if (i->f->get_period)
782 			i->f->get_period(sdev->sdev_target);
783 
784 		/* Here's the fallback sequence; first try turning off
785 		 * IU, then QAS (if we can control them), then finally
786 		 * fall down the periods */
787 		if (i->f->set_iu && spi_iu(starget)) {
788 			starget_printk(KERN_ERR, starget, "Domain Validation Disabling Information Units\n");
789 			DV_SET(iu, 0);
790 		} else if (i->f->set_qas && spi_qas(starget)) {
791 			starget_printk(KERN_ERR, starget, "Domain Validation Disabling Quick Arbitration and Selection\n");
792 			DV_SET(qas, 0);
793 		} else {
794 			newperiod = spi_period(starget);
795 			period = newperiod > period ? newperiod : period;
796 			if (period < 0x0d)
797 				period++;
798 			else
799 				period += period >> 1;
800 
801 			if (unlikely(period > 0xff || period == prevperiod)) {
802 				/* Total failure; set to async and return */
803 				starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
804 				DV_SET(offset, 0);
805 				return SPI_COMPARE_FAILURE;
806 			}
807 			starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
808 			DV_SET(period, period);
809 			prevperiod = period;
810 		}
811 	}
812 	return retval;
813 }
814 
815 static int
816 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
817 {
818 	int l, result;
819 
820 	/* first off do a test unit ready.  This can error out
821 	 * because of reservations or some other reason.  If it
822 	 * fails, the device won't let us write to the echo buffer
823 	 * so just return failure */
824 
825 	static const char spi_test_unit_ready[] = {
826 		TEST_UNIT_READY, 0, 0, 0, 0, 0
827 	};
828 
829 	static const char spi_read_buffer_descriptor[] = {
830 		READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
831 	};
832 
833 
834 	/* We send a set of three TURs to clear any outstanding
835 	 * unit attention conditions if they exist (Otherwise the
836 	 * buffer tests won't be happy).  If the TUR still fails
837 	 * (reservation conflict, device not ready, etc) just
838 	 * skip the write tests */
839 	for (l = 0; ; l++) {
840 		result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE,
841 				     NULL, 0, NULL);
842 
843 		if(result) {
844 			if(l >= 3)
845 				return 0;
846 		} else {
847 			/* TUR succeeded */
848 			break;
849 		}
850 	}
851 
852 	result = spi_execute(sdev, spi_read_buffer_descriptor,
853 			     DMA_FROM_DEVICE, buffer, 4, NULL);
854 
855 	if (result)
856 		/* Device has no echo buffer */
857 		return 0;
858 
859 	return buffer[3] + ((buffer[2] & 0x1f) << 8);
860 }
861 
862 static void
863 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
864 {
865 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
866 	struct scsi_target *starget = sdev->sdev_target;
867 	struct Scsi_Host *shost = sdev->host;
868 	int len = sdev->inquiry_len;
869 	int min_period = spi_min_period(starget);
870 	int max_width = spi_max_width(starget);
871 	/* first set us up for narrow async */
872 	DV_SET(offset, 0);
873 	DV_SET(width, 0);
874 
875 	if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
876 	    != SPI_COMPARE_SUCCESS) {
877 		starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
878 		/* FIXME: should probably offline the device here? */
879 		return;
880 	}
881 
882 	if (!spi_support_wide(starget)) {
883 		spi_max_width(starget) = 0;
884 		max_width = 0;
885 	}
886 
887 	/* test width */
888 	if (i->f->set_width && max_width) {
889 		i->f->set_width(starget, 1);
890 
891 		if (spi_dv_device_compare_inquiry(sdev, buffer,
892 						   buffer + len,
893 						   DV_LOOPS)
894 		    != SPI_COMPARE_SUCCESS) {
895 			starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
896 			i->f->set_width(starget, 0);
897 			/* Make sure we don't force wide back on by asking
898 			 * for a transfer period that requires it */
899 			max_width = 0;
900 			if (min_period < 10)
901 				min_period = 10;
902 		}
903 	}
904 
905 	if (!i->f->set_period)
906 		return;
907 
908 	/* device can't handle synchronous */
909 	if (!spi_support_sync(starget) && !spi_support_dt(starget))
910 		return;
911 
912 	/* len == -1 is the signal that we need to ascertain the
913 	 * presence of an echo buffer before trying to use it.  len ==
914 	 * 0 means we don't have an echo buffer */
915 	len = -1;
916 
917  retry:
918 
919 	/* now set up to the maximum */
920 	DV_SET(offset, spi_max_offset(starget));
921 	DV_SET(period, min_period);
922 
923 	/* try QAS requests; this should be harmless to set if the
924 	 * target supports it */
925 	if (spi_support_qas(starget) && spi_max_qas(starget)) {
926 		DV_SET(qas, 1);
927 	} else {
928 		DV_SET(qas, 0);
929 	}
930 
931 	if (spi_support_ius(starget) && spi_max_iu(starget) &&
932 	    min_period < 9) {
933 		/* This u320 (or u640). Set IU transfers */
934 		DV_SET(iu, 1);
935 		/* Then set the optional parameters */
936 		DV_SET(rd_strm, 1);
937 		DV_SET(wr_flow, 1);
938 		DV_SET(rti, 1);
939 		if (min_period == 8)
940 			DV_SET(pcomp_en, 1);
941 	} else {
942 		DV_SET(iu, 0);
943 	}
944 
945 	/* now that we've done all this, actually check the bus
946 	 * signal type (if known).  Some devices are stupid on
947 	 * a SE bus and still claim they can try LVD only settings */
948 	if (i->f->get_signalling)
949 		i->f->get_signalling(shost);
950 	if (spi_signalling(shost) == SPI_SIGNAL_SE ||
951 	    spi_signalling(shost) == SPI_SIGNAL_HVD ||
952 	    !spi_support_dt(starget)) {
953 		DV_SET(dt, 0);
954 	} else {
955 		DV_SET(dt, 1);
956 	}
957 	/* set width last because it will pull all the other
958 	 * parameters down to required values */
959 	DV_SET(width, max_width);
960 
961 	/* Do the read only INQUIRY tests */
962 	spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
963 		       spi_dv_device_compare_inquiry);
964 	/* See if we actually managed to negotiate and sustain DT */
965 	if (i->f->get_dt)
966 		i->f->get_dt(starget);
967 
968 	/* see if the device has an echo buffer.  If it does we can do
969 	 * the SPI pattern write tests.  Because of some broken
970 	 * devices, we *only* try this on a device that has actually
971 	 * negotiated DT */
972 
973 	if (len == -1 && spi_dt(starget))
974 		len = spi_dv_device_get_echo_buffer(sdev, buffer);
975 
976 	if (len <= 0) {
977 		starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
978 		return;
979 	}
980 
981 	if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
982 		starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
983 		len = SPI_MAX_ECHO_BUFFER_SIZE;
984 	}
985 
986 	if (spi_dv_retrain(sdev, buffer, buffer + len,
987 			   spi_dv_device_echo_buffer)
988 	    == SPI_COMPARE_SKIP_TEST) {
989 		/* OK, the stupid drive can't do a write echo buffer
990 		 * test after all, fall back to the read tests */
991 		len = 0;
992 		goto retry;
993 	}
994 }
995 
996 
997 /**	spi_dv_device - Do Domain Validation on the device
998  *	@sdev:		scsi device to validate
999  *
1000  *	Performs the domain validation on the given device in the
1001  *	current execution thread.  Since DV operations may sleep,
1002  *	the current thread must have user context.  Also no SCSI
1003  *	related locks that would deadlock I/O issued by the DV may
1004  *	be held.
1005  */
1006 void
1007 spi_dv_device(struct scsi_device *sdev)
1008 {
1009 	struct scsi_target *starget = sdev->sdev_target;
1010 	u8 *buffer;
1011 	const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
1012 
1013 	/*
1014 	 * Because this function and the power management code both call
1015 	 * scsi_device_quiesce(), it is not safe to perform domain validation
1016 	 * while suspend or resume is in progress. Hence the
1017 	 * lock/unlock_system_sleep() calls.
1018 	 */
1019 	lock_system_sleep();
1020 
1021 	if (unlikely(spi_dv_in_progress(starget)))
1022 		goto unlock;
1023 
1024 	if (unlikely(scsi_device_get(sdev)))
1025 		goto unlock;
1026 
1027 	spi_dv_in_progress(starget) = 1;
1028 
1029 	buffer = kzalloc(len, GFP_KERNEL);
1030 
1031 	if (unlikely(!buffer))
1032 		goto out_put;
1033 
1034 	/* We need to verify that the actual device will quiesce; the
1035 	 * later target quiesce is just a nice to have */
1036 	if (unlikely(scsi_device_quiesce(sdev)))
1037 		goto out_free;
1038 
1039 	scsi_target_quiesce(starget);
1040 
1041 	spi_dv_pending(starget) = 1;
1042 	mutex_lock(&spi_dv_mutex(starget));
1043 
1044 	starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
1045 
1046 	spi_dv_device_internal(sdev, buffer);
1047 
1048 	starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
1049 
1050 	mutex_unlock(&spi_dv_mutex(starget));
1051 	spi_dv_pending(starget) = 0;
1052 
1053 	scsi_target_resume(starget);
1054 
1055 	spi_initial_dv(starget) = 1;
1056 
1057  out_free:
1058 	kfree(buffer);
1059  out_put:
1060 	spi_dv_in_progress(starget) = 0;
1061 	scsi_device_put(sdev);
1062 unlock:
1063 	unlock_system_sleep();
1064 }
1065 EXPORT_SYMBOL(spi_dv_device);
1066 
1067 struct work_queue_wrapper {
1068 	struct work_struct	work;
1069 	struct scsi_device	*sdev;
1070 };
1071 
1072 static void
1073 spi_dv_device_work_wrapper(struct work_struct *work)
1074 {
1075 	struct work_queue_wrapper *wqw =
1076 		container_of(work, struct work_queue_wrapper, work);
1077 	struct scsi_device *sdev = wqw->sdev;
1078 
1079 	kfree(wqw);
1080 	spi_dv_device(sdev);
1081 	spi_dv_pending(sdev->sdev_target) = 0;
1082 	scsi_device_put(sdev);
1083 }
1084 
1085 
1086 /**
1087  *	spi_schedule_dv_device - schedule domain validation to occur on the device
1088  *	@sdev:	The device to validate
1089  *
1090  *	Identical to spi_dv_device() above, except that the DV will be
1091  *	scheduled to occur in a workqueue later.  All memory allocations
1092  *	are atomic, so may be called from any context including those holding
1093  *	SCSI locks.
1094  */
1095 void
1096 spi_schedule_dv_device(struct scsi_device *sdev)
1097 {
1098 	struct work_queue_wrapper *wqw =
1099 		kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
1100 
1101 	if (unlikely(!wqw))
1102 		return;
1103 
1104 	if (unlikely(spi_dv_pending(sdev->sdev_target))) {
1105 		kfree(wqw);
1106 		return;
1107 	}
1108 	/* Set pending early (dv_device doesn't check it, only sets it) */
1109 	spi_dv_pending(sdev->sdev_target) = 1;
1110 	if (unlikely(scsi_device_get(sdev))) {
1111 		kfree(wqw);
1112 		spi_dv_pending(sdev->sdev_target) = 0;
1113 		return;
1114 	}
1115 
1116 	INIT_WORK(&wqw->work, spi_dv_device_work_wrapper);
1117 	wqw->sdev = sdev;
1118 
1119 	schedule_work(&wqw->work);
1120 }
1121 EXPORT_SYMBOL(spi_schedule_dv_device);
1122 
1123 /**
1124  * spi_display_xfer_agreement - Print the current target transfer agreement
1125  * @starget: The target for which to display the agreement
1126  *
1127  * Each SPI port is required to maintain a transfer agreement for each
1128  * other port on the bus.  This function prints a one-line summary of
1129  * the current agreement; more detailed information is available in sysfs.
1130  */
1131 void spi_display_xfer_agreement(struct scsi_target *starget)
1132 {
1133 	struct spi_transport_attrs *tp;
1134 	tp = (struct spi_transport_attrs *)&starget->starget_data;
1135 
1136 	if (tp->offset > 0 && tp->period > 0) {
1137 		unsigned int picosec, kb100;
1138 		char *scsi = "FAST-?";
1139 		char tmp[8];
1140 
1141 		if (tp->period <= SPI_STATIC_PPR) {
1142 			picosec = ppr_to_ps[tp->period];
1143 			switch (tp->period) {
1144 				case  7: scsi = "FAST-320"; break;
1145 				case  8: scsi = "FAST-160"; break;
1146 				case  9: scsi = "FAST-80"; break;
1147 				case 10:
1148 				case 11: scsi = "FAST-40"; break;
1149 				case 12: scsi = "FAST-20"; break;
1150 			}
1151 		} else {
1152 			picosec = tp->period * 4000;
1153 			if (tp->period < 25)
1154 				scsi = "FAST-20";
1155 			else if (tp->period < 50)
1156 				scsi = "FAST-10";
1157 			else
1158 				scsi = "FAST-5";
1159 		}
1160 
1161 		kb100 = (10000000 + picosec / 2) / picosec;
1162 		if (tp->width)
1163 			kb100 *= 2;
1164 		sprint_frac(tmp, picosec, 1000);
1165 
1166 		dev_info(&starget->dev,
1167 			 "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1168 			 scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1169 			 tp->dt ? "DT" : "ST",
1170 			 tp->iu ? " IU" : "",
1171 			 tp->qas  ? " QAS" : "",
1172 			 tp->rd_strm ? " RDSTRM" : "",
1173 			 tp->rti ? " RTI" : "",
1174 			 tp->wr_flow ? " WRFLOW" : "",
1175 			 tp->pcomp_en ? " PCOMP" : "",
1176 			 tp->hold_mcs ? " HMCS" : "",
1177 			 tmp, tp->offset);
1178 	} else {
1179 		dev_info(&starget->dev, "%sasynchronous\n",
1180 				tp->width ? "wide " : "");
1181 	}
1182 }
1183 EXPORT_SYMBOL(spi_display_xfer_agreement);
1184 
1185 int spi_populate_width_msg(unsigned char *msg, int width)
1186 {
1187 	msg[0] = EXTENDED_MESSAGE;
1188 	msg[1] = 2;
1189 	msg[2] = EXTENDED_WDTR;
1190 	msg[3] = width;
1191 	return 4;
1192 }
1193 EXPORT_SYMBOL_GPL(spi_populate_width_msg);
1194 
1195 int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
1196 {
1197 	msg[0] = EXTENDED_MESSAGE;
1198 	msg[1] = 3;
1199 	msg[2] = EXTENDED_SDTR;
1200 	msg[3] = period;
1201 	msg[4] = offset;
1202 	return 5;
1203 }
1204 EXPORT_SYMBOL_GPL(spi_populate_sync_msg);
1205 
1206 int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
1207 		int width, int options)
1208 {
1209 	msg[0] = EXTENDED_MESSAGE;
1210 	msg[1] = 6;
1211 	msg[2] = EXTENDED_PPR;
1212 	msg[3] = period;
1213 	msg[4] = 0;
1214 	msg[5] = offset;
1215 	msg[6] = width;
1216 	msg[7] = options;
1217 	return 8;
1218 }
1219 EXPORT_SYMBOL_GPL(spi_populate_ppr_msg);
1220 
1221 /**
1222  * spi_populate_tag_msg - place a tag message in a buffer
1223  * @msg:	pointer to the area to place the tag
1224  * @cmd:	pointer to the scsi command for the tag
1225  *
1226  * Notes:
1227  *	designed to create the correct type of tag message for the
1228  *	particular request.  Returns the size of the tag message.
1229  *	May return 0 if TCQ is disabled for this device.
1230  **/
1231 int spi_populate_tag_msg(unsigned char *msg, struct scsi_cmnd *cmd)
1232 {
1233         if (cmd->flags & SCMD_TAGGED) {
1234 		*msg++ = SIMPLE_QUEUE_TAG;
1235         	*msg++ = cmd->request->tag;
1236         	return 2;
1237 	}
1238 
1239 	return 0;
1240 }
1241 EXPORT_SYMBOL_GPL(spi_populate_tag_msg);
1242 
1243 #ifdef CONFIG_SCSI_CONSTANTS
1244 static const char * const one_byte_msgs[] = {
1245 /* 0x00 */ "Task Complete", NULL /* Extended Message */, "Save Pointers",
1246 /* 0x03 */ "Restore Pointers", "Disconnect", "Initiator Error",
1247 /* 0x06 */ "Abort Task Set", "Message Reject", "Nop", "Message Parity Error",
1248 /* 0x0a */ "Linked Command Complete", "Linked Command Complete w/flag",
1249 /* 0x0c */ "Target Reset", "Abort Task", "Clear Task Set",
1250 /* 0x0f */ "Initiate Recovery", "Release Recovery",
1251 /* 0x11 */ "Terminate Process", "Continue Task", "Target Transfer Disable",
1252 /* 0x14 */ NULL, NULL, "Clear ACA", "LUN Reset"
1253 };
1254 
1255 static const char * const two_byte_msgs[] = {
1256 /* 0x20 */ "Simple Queue Tag", "Head of Queue Tag", "Ordered Queue Tag",
1257 /* 0x23 */ "Ignore Wide Residue", "ACA"
1258 };
1259 
1260 static const char * const extended_msgs[] = {
1261 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
1262 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
1263 /* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
1264 };
1265 
1266 static void print_nego(const unsigned char *msg, int per, int off, int width)
1267 {
1268 	if (per) {
1269 		char buf[20];
1270 		period_to_str(buf, msg[per]);
1271 		printk("period = %s ns ", buf);
1272 	}
1273 
1274 	if (off)
1275 		printk("offset = %d ", msg[off]);
1276 	if (width)
1277 		printk("width = %d ", 8 << msg[width]);
1278 }
1279 
1280 static void print_ptr(const unsigned char *msg, int msb, const char *desc)
1281 {
1282 	int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
1283 			msg[msb+3];
1284 	printk("%s = %d ", desc, ptr);
1285 }
1286 
1287 int spi_print_msg(const unsigned char *msg)
1288 {
1289 	int len = 1, i;
1290 	if (msg[0] == EXTENDED_MESSAGE) {
1291 		len = 2 + msg[1];
1292 		if (len == 2)
1293 			len += 256;
1294 		if (msg[2] < ARRAY_SIZE(extended_msgs))
1295 			printk ("%s ", extended_msgs[msg[2]]);
1296 		else
1297 			printk ("Extended Message, reserved code (0x%02x) ",
1298 				(int) msg[2]);
1299 		switch (msg[2]) {
1300 		case EXTENDED_MODIFY_DATA_POINTER:
1301 			print_ptr(msg, 3, "pointer");
1302 			break;
1303 		case EXTENDED_SDTR:
1304 			print_nego(msg, 3, 4, 0);
1305 			break;
1306 		case EXTENDED_WDTR:
1307 			print_nego(msg, 0, 0, 3);
1308 			break;
1309 		case EXTENDED_PPR:
1310 			print_nego(msg, 3, 5, 6);
1311 			break;
1312 		case EXTENDED_MODIFY_BIDI_DATA_PTR:
1313 			print_ptr(msg, 3, "out");
1314 			print_ptr(msg, 7, "in");
1315 			break;
1316 		default:
1317 		for (i = 2; i < len; ++i)
1318 			printk("%02x ", msg[i]);
1319 		}
1320 	/* Identify */
1321 	} else if (msg[0] & 0x80) {
1322 		printk("Identify disconnect %sallowed %s %d ",
1323 			(msg[0] & 0x40) ? "" : "not ",
1324 			(msg[0] & 0x20) ? "target routine" : "lun",
1325 			msg[0] & 0x7);
1326 	/* Normal One byte */
1327 	} else if (msg[0] < 0x1f) {
1328 		if (msg[0] < ARRAY_SIZE(one_byte_msgs) && one_byte_msgs[msg[0]])
1329 			printk("%s ", one_byte_msgs[msg[0]]);
1330 		else
1331 			printk("reserved (%02x) ", msg[0]);
1332 	} else if (msg[0] == 0x55) {
1333 		printk("QAS Request ");
1334 	/* Two byte */
1335 	} else if (msg[0] <= 0x2f) {
1336 		if ((msg[0] - 0x20) < ARRAY_SIZE(two_byte_msgs))
1337 			printk("%s %02x ", two_byte_msgs[msg[0] - 0x20],
1338 				msg[1]);
1339 		else
1340 			printk("reserved two byte (%02x %02x) ",
1341 				msg[0], msg[1]);
1342 		len = 2;
1343 	} else
1344 		printk("reserved ");
1345 	return len;
1346 }
1347 EXPORT_SYMBOL(spi_print_msg);
1348 
1349 #else  /* ifndef CONFIG_SCSI_CONSTANTS */
1350 
1351 int spi_print_msg(const unsigned char *msg)
1352 {
1353 	int len = 1, i;
1354 
1355 	if (msg[0] == EXTENDED_MESSAGE) {
1356 		len = 2 + msg[1];
1357 		if (len == 2)
1358 			len += 256;
1359 		for (i = 0; i < len; ++i)
1360 			printk("%02x ", msg[i]);
1361 	/* Identify */
1362 	} else if (msg[0] & 0x80) {
1363 		printk("%02x ", msg[0]);
1364 	/* Normal One byte */
1365 	} else if ((msg[0] < 0x1f) || (msg[0] == 0x55)) {
1366 		printk("%02x ", msg[0]);
1367 	/* Two byte */
1368 	} else if (msg[0] <= 0x2f) {
1369 		printk("%02x %02x", msg[0], msg[1]);
1370 		len = 2;
1371 	} else
1372 		printk("%02x ", msg[0]);
1373 	return len;
1374 }
1375 EXPORT_SYMBOL(spi_print_msg);
1376 #endif /* ! CONFIG_SCSI_CONSTANTS */
1377 
1378 static int spi_device_match(struct attribute_container *cont,
1379 			    struct device *dev)
1380 {
1381 	struct scsi_device *sdev;
1382 	struct Scsi_Host *shost;
1383 	struct spi_internal *i;
1384 
1385 	if (!scsi_is_sdev_device(dev))
1386 		return 0;
1387 
1388 	sdev = to_scsi_device(dev);
1389 	shost = sdev->host;
1390 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1391 	    != &spi_host_class.class)
1392 		return 0;
1393 	/* Note: this class has no device attributes, so it has
1394 	 * no per-HBA allocation and thus we don't need to distinguish
1395 	 * the attribute containers for the device */
1396 	i = to_spi_internal(shost->transportt);
1397 	if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1398 		return 0;
1399 	return 1;
1400 }
1401 
1402 static int spi_target_match(struct attribute_container *cont,
1403 			    struct device *dev)
1404 {
1405 	struct Scsi_Host *shost;
1406 	struct scsi_target *starget;
1407 	struct spi_internal *i;
1408 
1409 	if (!scsi_is_target_device(dev))
1410 		return 0;
1411 
1412 	shost = dev_to_shost(dev->parent);
1413 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1414 	    != &spi_host_class.class)
1415 		return 0;
1416 
1417 	i = to_spi_internal(shost->transportt);
1418 	starget = to_scsi_target(dev);
1419 
1420 	if (i->f->deny_binding && i->f->deny_binding(starget))
1421 		return 0;
1422 
1423 	return &i->t.target_attrs.ac == cont;
1424 }
1425 
1426 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1427 			       "spi_transport",
1428 			       spi_setup_transport_attrs,
1429 			       NULL,
1430 			       spi_target_configure);
1431 
1432 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1433 				    spi_device_match,
1434 				    spi_device_configure);
1435 
1436 static struct attribute *host_attributes[] = {
1437 	&dev_attr_signalling.attr,
1438 	&dev_attr_host_width.attr,
1439 	&dev_attr_hba_id.attr,
1440 	NULL
1441 };
1442 
1443 static struct attribute_group host_attribute_group = {
1444 	.attrs = host_attributes,
1445 };
1446 
1447 static int spi_host_configure(struct transport_container *tc,
1448 			      struct device *dev,
1449 			      struct device *cdev)
1450 {
1451 	struct kobject *kobj = &cdev->kobj;
1452 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1453 	struct spi_internal *si = to_spi_internal(shost->transportt);
1454 	struct attribute *attr = &dev_attr_signalling.attr;
1455 	int rc = 0;
1456 
1457 	if (si->f->set_signalling)
1458 		rc = sysfs_chmod_file(kobj, attr, attr->mode | S_IWUSR);
1459 
1460 	return rc;
1461 }
1462 
1463 /* returns true if we should be showing the variable.  Also
1464  * overloads the return by setting 1<<1 if the attribute should
1465  * be writeable */
1466 #define TARGET_ATTRIBUTE_HELPER(name) \
1467 	(si->f->show_##name ? S_IRUGO : 0) | \
1468 	(si->f->set_##name ? S_IWUSR : 0)
1469 
1470 static umode_t target_attribute_is_visible(struct kobject *kobj,
1471 					  struct attribute *attr, int i)
1472 {
1473 	struct device *cdev = container_of(kobj, struct device, kobj);
1474 	struct scsi_target *starget = transport_class_to_starget(cdev);
1475 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1476 	struct spi_internal *si = to_spi_internal(shost->transportt);
1477 
1478 	if (attr == &dev_attr_period.attr &&
1479 	    spi_support_sync(starget))
1480 		return TARGET_ATTRIBUTE_HELPER(period);
1481 	else if (attr == &dev_attr_min_period.attr &&
1482 		 spi_support_sync(starget))
1483 		return TARGET_ATTRIBUTE_HELPER(period);
1484 	else if (attr == &dev_attr_offset.attr &&
1485 		 spi_support_sync(starget))
1486 		return TARGET_ATTRIBUTE_HELPER(offset);
1487 	else if (attr == &dev_attr_max_offset.attr &&
1488 		 spi_support_sync(starget))
1489 		return TARGET_ATTRIBUTE_HELPER(offset);
1490 	else if (attr == &dev_attr_width.attr &&
1491 		 spi_support_wide(starget))
1492 		return TARGET_ATTRIBUTE_HELPER(width);
1493 	else if (attr == &dev_attr_max_width.attr &&
1494 		 spi_support_wide(starget))
1495 		return TARGET_ATTRIBUTE_HELPER(width);
1496 	else if (attr == &dev_attr_iu.attr &&
1497 		 spi_support_ius(starget))
1498 		return TARGET_ATTRIBUTE_HELPER(iu);
1499 	else if (attr == &dev_attr_max_iu.attr &&
1500 		 spi_support_ius(starget))
1501 		return TARGET_ATTRIBUTE_HELPER(iu);
1502 	else if (attr == &dev_attr_dt.attr &&
1503 		 spi_support_dt(starget))
1504 		return TARGET_ATTRIBUTE_HELPER(dt);
1505 	else if (attr == &dev_attr_qas.attr &&
1506 		 spi_support_qas(starget))
1507 		return TARGET_ATTRIBUTE_HELPER(qas);
1508 	else if (attr == &dev_attr_max_qas.attr &&
1509 		 spi_support_qas(starget))
1510 		return TARGET_ATTRIBUTE_HELPER(qas);
1511 	else if (attr == &dev_attr_wr_flow.attr &&
1512 		 spi_support_ius(starget))
1513 		return TARGET_ATTRIBUTE_HELPER(wr_flow);
1514 	else if (attr == &dev_attr_rd_strm.attr &&
1515 		 spi_support_ius(starget))
1516 		return TARGET_ATTRIBUTE_HELPER(rd_strm);
1517 	else if (attr == &dev_attr_rti.attr &&
1518 		 spi_support_ius(starget))
1519 		return TARGET_ATTRIBUTE_HELPER(rti);
1520 	else if (attr == &dev_attr_pcomp_en.attr &&
1521 		 spi_support_ius(starget))
1522 		return TARGET_ATTRIBUTE_HELPER(pcomp_en);
1523 	else if (attr == &dev_attr_hold_mcs.attr &&
1524 		 spi_support_ius(starget))
1525 		return TARGET_ATTRIBUTE_HELPER(hold_mcs);
1526 	else if (attr == &dev_attr_revalidate.attr)
1527 		return S_IWUSR;
1528 
1529 	return 0;
1530 }
1531 
1532 static struct attribute *target_attributes[] = {
1533 	&dev_attr_period.attr,
1534 	&dev_attr_min_period.attr,
1535 	&dev_attr_offset.attr,
1536 	&dev_attr_max_offset.attr,
1537 	&dev_attr_width.attr,
1538 	&dev_attr_max_width.attr,
1539 	&dev_attr_iu.attr,
1540 	&dev_attr_max_iu.attr,
1541 	&dev_attr_dt.attr,
1542 	&dev_attr_qas.attr,
1543 	&dev_attr_max_qas.attr,
1544 	&dev_attr_wr_flow.attr,
1545 	&dev_attr_rd_strm.attr,
1546 	&dev_attr_rti.attr,
1547 	&dev_attr_pcomp_en.attr,
1548 	&dev_attr_hold_mcs.attr,
1549 	&dev_attr_revalidate.attr,
1550 	NULL
1551 };
1552 
1553 static struct attribute_group target_attribute_group = {
1554 	.attrs = target_attributes,
1555 	.is_visible = target_attribute_is_visible,
1556 };
1557 
1558 static int spi_target_configure(struct transport_container *tc,
1559 				struct device *dev,
1560 				struct device *cdev)
1561 {
1562 	struct kobject *kobj = &cdev->kobj;
1563 
1564 	/* force an update based on parameters read from the device */
1565 	sysfs_update_group(kobj, &target_attribute_group);
1566 
1567 	return 0;
1568 }
1569 
1570 struct scsi_transport_template *
1571 spi_attach_transport(struct spi_function_template *ft)
1572 {
1573 	struct spi_internal *i = kzalloc(sizeof(struct spi_internal),
1574 					 GFP_KERNEL);
1575 
1576 	if (unlikely(!i))
1577 		return NULL;
1578 
1579 	i->t.target_attrs.ac.class = &spi_transport_class.class;
1580 	i->t.target_attrs.ac.grp = &target_attribute_group;
1581 	i->t.target_attrs.ac.match = spi_target_match;
1582 	transport_container_register(&i->t.target_attrs);
1583 	i->t.target_size = sizeof(struct spi_transport_attrs);
1584 	i->t.host_attrs.ac.class = &spi_host_class.class;
1585 	i->t.host_attrs.ac.grp = &host_attribute_group;
1586 	i->t.host_attrs.ac.match = spi_host_match;
1587 	transport_container_register(&i->t.host_attrs);
1588 	i->t.host_size = sizeof(struct spi_host_attrs);
1589 	i->f = ft;
1590 
1591 	return &i->t;
1592 }
1593 EXPORT_SYMBOL(spi_attach_transport);
1594 
1595 void spi_release_transport(struct scsi_transport_template *t)
1596 {
1597 	struct spi_internal *i = to_spi_internal(t);
1598 
1599 	transport_container_unregister(&i->t.target_attrs);
1600 	transport_container_unregister(&i->t.host_attrs);
1601 
1602 	kfree(i);
1603 }
1604 EXPORT_SYMBOL(spi_release_transport);
1605 
1606 static __init int spi_transport_init(void)
1607 {
1608 	int error = scsi_dev_info_add_list(SCSI_DEVINFO_SPI,
1609 					   "SCSI Parallel Transport Class");
1610 	if (!error) {
1611 		int i;
1612 
1613 		for (i = 0; spi_static_device_list[i].vendor; i++)
1614 			scsi_dev_info_list_add_keyed(1,	/* compatible */
1615 						     spi_static_device_list[i].vendor,
1616 						     spi_static_device_list[i].model,
1617 						     NULL,
1618 						     spi_static_device_list[i].flags,
1619 						     SCSI_DEVINFO_SPI);
1620 	}
1621 
1622 	error = transport_class_register(&spi_transport_class);
1623 	if (error)
1624 		return error;
1625 	error = anon_transport_class_register(&spi_device_class);
1626 	return transport_class_register(&spi_host_class);
1627 }
1628 
1629 static void __exit spi_transport_exit(void)
1630 {
1631 	transport_class_unregister(&spi_transport_class);
1632 	anon_transport_class_unregister(&spi_device_class);
1633 	transport_class_unregister(&spi_host_class);
1634 	scsi_dev_info_remove_list(SCSI_DEVINFO_SPI);
1635 }
1636 
1637 MODULE_AUTHOR("Martin Hicks");
1638 MODULE_DESCRIPTION("SPI Transport Attributes");
1639 MODULE_LICENSE("GPL");
1640 
1641 module_init(spi_transport_init);
1642 module_exit(spi_transport_exit);
1643