xref: /openbmc/linux/drivers/scsi/scsi_transport_spi.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 <scsi/scsi.h>
30 #include "scsi_priv.h"
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_cmnd.h>
34 #include <scsi/scsi_eh.h>
35 #include <scsi/scsi_transport.h>
36 #include <scsi/scsi_transport_spi.h>
37 
38 #define SPI_NUM_ATTRS 14	/* increase this if you add attributes */
39 #define SPI_OTHER_ATTRS 1	/* Increase this if you add "always
40 				 * on" attributes */
41 #define SPI_HOST_ATTRS	1
42 
43 #define SPI_MAX_ECHO_BUFFER_SIZE	4096
44 
45 #define DV_LOOPS	3
46 #define DV_TIMEOUT	(10*HZ)
47 #define DV_RETRIES	3	/* should only need at most
48 				 * two cc/ua clears */
49 
50 /* Our blacklist flags */
51 enum {
52 	SPI_BLIST_NOIUS = 0x1,
53 };
54 
55 /* blacklist table, modelled on scsi_devinfo.c */
56 static struct {
57 	char *vendor;
58 	char *model;
59 	unsigned flags;
60 } spi_static_device_list[] __initdata = {
61 	{"HP", "Ultrium 3-SCSI", SPI_BLIST_NOIUS },
62 	{"IBM", "ULTRIUM-TD3", SPI_BLIST_NOIUS },
63 	{NULL, NULL, 0}
64 };
65 
66 /* Private data accessors (keep these out of the header file) */
67 #define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
68 #define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
69 
70 struct spi_internal {
71 	struct scsi_transport_template t;
72 	struct spi_function_template *f;
73 };
74 
75 #define to_spi_internal(tmpl)	container_of(tmpl, struct spi_internal, t)
76 
77 static const int ppr_to_ps[] = {
78 	/* The PPR values 0-6 are reserved, fill them in when
79 	 * the committee defines them */
80 	-1,			/* 0x00 */
81 	-1,			/* 0x01 */
82 	-1,			/* 0x02 */
83 	-1,			/* 0x03 */
84 	-1,			/* 0x04 */
85 	-1,			/* 0x05 */
86 	-1,			/* 0x06 */
87 	 3125,			/* 0x07 */
88 	 6250,			/* 0x08 */
89 	12500,			/* 0x09 */
90 	25000,			/* 0x0a */
91 	30300,			/* 0x0b */
92 	50000,			/* 0x0c */
93 };
94 /* The PPR values at which you calculate the period in ns by multiplying
95  * by 4 */
96 #define SPI_STATIC_PPR	0x0c
97 
98 static int sprint_frac(char *dest, int value, int denom)
99 {
100 	int frac = value % denom;
101 	int result = sprintf(dest, "%d", value / denom);
102 
103 	if (frac == 0)
104 		return result;
105 	dest[result++] = '.';
106 
107 	do {
108 		denom /= 10;
109 		sprintf(dest + result, "%d", frac / denom);
110 		result++;
111 		frac %= denom;
112 	} while (frac);
113 
114 	dest[result++] = '\0';
115 	return result;
116 }
117 
118 static int spi_execute(struct scsi_device *sdev, const void *cmd,
119 		       enum dma_data_direction dir,
120 		       void *buffer, unsigned bufflen,
121 		       struct scsi_sense_hdr *sshdr)
122 {
123 	int i, result;
124 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
125 
126 	for(i = 0; i < DV_RETRIES; i++) {
127 		result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
128 				      sense, DV_TIMEOUT, /* retries */ 1,
129 				      REQ_FAILFAST_DEV |
130 				      REQ_FAILFAST_TRANSPORT |
131 				      REQ_FAILFAST_DRIVER,
132 				      NULL);
133 		if (driver_byte(result) & DRIVER_SENSE) {
134 			struct scsi_sense_hdr sshdr_tmp;
135 			if (!sshdr)
136 				sshdr = &sshdr_tmp;
137 
138 			if (scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE,
139 						 sshdr)
140 			    && sshdr->sense_key == UNIT_ATTENTION)
141 				continue;
142 		}
143 		break;
144 	}
145 	return result;
146 }
147 
148 static struct {
149 	enum spi_signal_type	value;
150 	char			*name;
151 } signal_types[] = {
152 	{ SPI_SIGNAL_UNKNOWN, "unknown" },
153 	{ SPI_SIGNAL_SE, "SE" },
154 	{ SPI_SIGNAL_LVD, "LVD" },
155 	{ SPI_SIGNAL_HVD, "HVD" },
156 };
157 
158 static inline const char *spi_signal_to_string(enum spi_signal_type type)
159 {
160 	int i;
161 
162 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
163 		if (type == signal_types[i].value)
164 			return signal_types[i].name;
165 	}
166 	return NULL;
167 }
168 static inline enum spi_signal_type spi_signal_to_value(const char *name)
169 {
170 	int i, len;
171 
172 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
173 		len =  strlen(signal_types[i].name);
174 		if (strncmp(name, signal_types[i].name, len) == 0 &&
175 		    (name[len] == '\n' || name[len] == '\0'))
176 			return signal_types[i].value;
177 	}
178 	return SPI_SIGNAL_UNKNOWN;
179 }
180 
181 static int spi_host_setup(struct transport_container *tc, struct device *dev,
182 			  struct device *cdev)
183 {
184 	struct Scsi_Host *shost = dev_to_shost(dev);
185 
186 	spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
187 
188 	return 0;
189 }
190 
191 static int spi_host_configure(struct transport_container *tc,
192 			      struct device *dev,
193 			      struct device *cdev);
194 
195 static DECLARE_TRANSPORT_CLASS(spi_host_class,
196 			       "spi_host",
197 			       spi_host_setup,
198 			       NULL,
199 			       spi_host_configure);
200 
201 static int spi_host_match(struct attribute_container *cont,
202 			  struct device *dev)
203 {
204 	struct Scsi_Host *shost;
205 
206 	if (!scsi_is_host_device(dev))
207 		return 0;
208 
209 	shost = dev_to_shost(dev);
210 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
211 	    != &spi_host_class.class)
212 		return 0;
213 
214 	return &shost->transportt->host_attrs.ac == cont;
215 }
216 
217 static int spi_target_configure(struct transport_container *tc,
218 				struct device *dev,
219 				struct device *cdev);
220 
221 static int spi_device_configure(struct transport_container *tc,
222 				struct device *dev,
223 				struct device *cdev)
224 {
225 	struct scsi_device *sdev = to_scsi_device(dev);
226 	struct scsi_target *starget = sdev->sdev_target;
227 	unsigned 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 #define DV_SET(x, y)			\
601 	if(i->f->set_##x)		\
602 		i->f->set_##x(sdev->sdev_target, y)
603 
604 enum spi_compare_returns {
605 	SPI_COMPARE_SUCCESS,
606 	SPI_COMPARE_FAILURE,
607 	SPI_COMPARE_SKIP_TEST,
608 };
609 
610 
611 /* This is for read/write Domain Validation:  If the device supports
612  * an echo buffer, we do read/write tests to it */
613 static enum spi_compare_returns
614 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
615 			  u8 *ptr, const int retries)
616 {
617 	int len = ptr - buffer;
618 	int j, k, r, result;
619 	unsigned int pattern = 0x0000ffff;
620 	struct scsi_sense_hdr sshdr;
621 
622 	const char spi_write_buffer[] = {
623 		WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
624 	};
625 	const char spi_read_buffer[] = {
626 		READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
627 	};
628 
629 	/* set up the pattern buffer.  Doesn't matter if we spill
630 	 * slightly beyond since that's where the read buffer is */
631 	for (j = 0; j < len; ) {
632 
633 		/* fill the buffer with counting (test a) */
634 		for ( ; j < min(len, 32); j++)
635 			buffer[j] = j;
636 		k = j;
637 		/* fill the buffer with alternating words of 0x0 and
638 		 * 0xffff (test b) */
639 		for ( ; j < min(len, k + 32); j += 2) {
640 			u16 *word = (u16 *)&buffer[j];
641 
642 			*word = (j & 0x02) ? 0x0000 : 0xffff;
643 		}
644 		k = j;
645 		/* fill with crosstalk (alternating 0x5555 0xaaa)
646                  * (test c) */
647 		for ( ; j < min(len, k + 32); j += 2) {
648 			u16 *word = (u16 *)&buffer[j];
649 
650 			*word = (j & 0x02) ? 0x5555 : 0xaaaa;
651 		}
652 		k = j;
653 		/* fill with shifting bits (test d) */
654 		for ( ; j < min(len, k + 32); j += 4) {
655 			u32 *word = (unsigned int *)&buffer[j];
656 			u32 roll = (pattern & 0x80000000) ? 1 : 0;
657 
658 			*word = pattern;
659 			pattern = (pattern << 1) | roll;
660 		}
661 		/* don't bother with random data (test e) */
662 	}
663 
664 	for (r = 0; r < retries; r++) {
665 		result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
666 				     buffer, len, &sshdr);
667 		if(result || !scsi_device_online(sdev)) {
668 
669 			scsi_device_set_state(sdev, SDEV_QUIESCE);
670 			if (scsi_sense_valid(&sshdr)
671 			    && sshdr.sense_key == ILLEGAL_REQUEST
672 			    /* INVALID FIELD IN CDB */
673 			    && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
674 				/* This would mean that the drive lied
675 				 * to us about supporting an echo
676 				 * buffer (unfortunately some Western
677 				 * Digital drives do precisely this)
678 				 */
679 				return SPI_COMPARE_SKIP_TEST;
680 
681 
682 			sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
683 			return SPI_COMPARE_FAILURE;
684 		}
685 
686 		memset(ptr, 0, len);
687 		spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
688 			    ptr, len, NULL);
689 		scsi_device_set_state(sdev, SDEV_QUIESCE);
690 
691 		if (memcmp(buffer, ptr, len) != 0)
692 			return SPI_COMPARE_FAILURE;
693 	}
694 	return SPI_COMPARE_SUCCESS;
695 }
696 
697 /* This is for the simplest form of Domain Validation: a read test
698  * on the inquiry data from the device */
699 static enum spi_compare_returns
700 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
701 			      u8 *ptr, const int retries)
702 {
703 	int r, result;
704 	const int len = sdev->inquiry_len;
705 	const char spi_inquiry[] = {
706 		INQUIRY, 0, 0, 0, len, 0
707 	};
708 
709 	for (r = 0; r < retries; r++) {
710 		memset(ptr, 0, len);
711 
712 		result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
713 				     ptr, len, NULL);
714 
715 		if(result || !scsi_device_online(sdev)) {
716 			scsi_device_set_state(sdev, SDEV_QUIESCE);
717 			return SPI_COMPARE_FAILURE;
718 		}
719 
720 		/* If we don't have the inquiry data already, the
721 		 * first read gets it */
722 		if (ptr == buffer) {
723 			ptr += len;
724 			--r;
725 			continue;
726 		}
727 
728 		if (memcmp(buffer, ptr, len) != 0)
729 			/* failure */
730 			return SPI_COMPARE_FAILURE;
731 	}
732 	return SPI_COMPARE_SUCCESS;
733 }
734 
735 static enum spi_compare_returns
736 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
737 	       enum spi_compare_returns
738 	       (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
739 {
740 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
741 	struct scsi_target *starget = sdev->sdev_target;
742 	int period = 0, prevperiod = 0;
743 	enum spi_compare_returns retval;
744 
745 
746 	for (;;) {
747 		int newperiod;
748 		retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
749 
750 		if (retval == SPI_COMPARE_SUCCESS
751 		    || retval == SPI_COMPARE_SKIP_TEST)
752 			break;
753 
754 		/* OK, retrain, fallback */
755 		if (i->f->get_iu)
756 			i->f->get_iu(starget);
757 		if (i->f->get_qas)
758 			i->f->get_qas(starget);
759 		if (i->f->get_period)
760 			i->f->get_period(sdev->sdev_target);
761 
762 		/* Here's the fallback sequence; first try turning off
763 		 * IU, then QAS (if we can control them), then finally
764 		 * fall down the periods */
765 		if (i->f->set_iu && spi_iu(starget)) {
766 			starget_printk(KERN_ERR, starget, "Domain Validation Disabing Information Units\n");
767 			DV_SET(iu, 0);
768 		} else if (i->f->set_qas && spi_qas(starget)) {
769 			starget_printk(KERN_ERR, starget, "Domain Validation Disabing Quick Arbitration and Selection\n");
770 			DV_SET(qas, 0);
771 		} else {
772 			newperiod = spi_period(starget);
773 			period = newperiod > period ? newperiod : period;
774 			if (period < 0x0d)
775 				period++;
776 			else
777 				period += period >> 1;
778 
779 			if (unlikely(period > 0xff || period == prevperiod)) {
780 				/* Total failure; set to async and return */
781 				starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
782 				DV_SET(offset, 0);
783 				return SPI_COMPARE_FAILURE;
784 			}
785 			starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
786 			DV_SET(period, period);
787 			prevperiod = period;
788 		}
789 	}
790 	return retval;
791 }
792 
793 static int
794 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
795 {
796 	int l, result;
797 
798 	/* first off do a test unit ready.  This can error out
799 	 * because of reservations or some other reason.  If it
800 	 * fails, the device won't let us write to the echo buffer
801 	 * so just return failure */
802 
803 	const char spi_test_unit_ready[] = {
804 		TEST_UNIT_READY, 0, 0, 0, 0, 0
805 	};
806 
807 	const char spi_read_buffer_descriptor[] = {
808 		READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
809 	};
810 
811 
812 	/* We send a set of three TURs to clear any outstanding
813 	 * unit attention conditions if they exist (Otherwise the
814 	 * buffer tests won't be happy).  If the TUR still fails
815 	 * (reservation conflict, device not ready, etc) just
816 	 * skip the write tests */
817 	for (l = 0; ; l++) {
818 		result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE,
819 				     NULL, 0, NULL);
820 
821 		if(result) {
822 			if(l >= 3)
823 				return 0;
824 		} else {
825 			/* TUR succeeded */
826 			break;
827 		}
828 	}
829 
830 	result = spi_execute(sdev, spi_read_buffer_descriptor,
831 			     DMA_FROM_DEVICE, buffer, 4, NULL);
832 
833 	if (result)
834 		/* Device has no echo buffer */
835 		return 0;
836 
837 	return buffer[3] + ((buffer[2] & 0x1f) << 8);
838 }
839 
840 static void
841 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
842 {
843 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
844 	struct scsi_target *starget = sdev->sdev_target;
845 	struct Scsi_Host *shost = sdev->host;
846 	int len = sdev->inquiry_len;
847 	int min_period = spi_min_period(starget);
848 	int max_width = spi_max_width(starget);
849 	/* first set us up for narrow async */
850 	DV_SET(offset, 0);
851 	DV_SET(width, 0);
852 
853 	if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
854 	    != SPI_COMPARE_SUCCESS) {
855 		starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
856 		/* FIXME: should probably offline the device here? */
857 		return;
858 	}
859 
860 	if (!spi_support_wide(starget)) {
861 		spi_max_width(starget) = 0;
862 		max_width = 0;
863 	}
864 
865 	/* test width */
866 	if (i->f->set_width && max_width) {
867 		i->f->set_width(starget, 1);
868 
869 		if (spi_dv_device_compare_inquiry(sdev, buffer,
870 						   buffer + len,
871 						   DV_LOOPS)
872 		    != SPI_COMPARE_SUCCESS) {
873 			starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
874 			i->f->set_width(starget, 0);
875 			/* Make sure we don't force wide back on by asking
876 			 * for a transfer period that requires it */
877 			max_width = 0;
878 			if (min_period < 10)
879 				min_period = 10;
880 		}
881 	}
882 
883 	if (!i->f->set_period)
884 		return;
885 
886 	/* device can't handle synchronous */
887 	if (!spi_support_sync(starget) && !spi_support_dt(starget))
888 		return;
889 
890 	/* len == -1 is the signal that we need to ascertain the
891 	 * presence of an echo buffer before trying to use it.  len ==
892 	 * 0 means we don't have an echo buffer */
893 	len = -1;
894 
895  retry:
896 
897 	/* now set up to the maximum */
898 	DV_SET(offset, spi_max_offset(starget));
899 	DV_SET(period, min_period);
900 
901 	/* try QAS requests; this should be harmless to set if the
902 	 * target supports it */
903 	if (spi_support_qas(starget) && spi_max_qas(starget)) {
904 		DV_SET(qas, 1);
905 	} else {
906 		DV_SET(qas, 0);
907 	}
908 
909 	if (spi_support_ius(starget) && spi_max_iu(starget) &&
910 	    min_period < 9) {
911 		/* This u320 (or u640). Set IU transfers */
912 		DV_SET(iu, 1);
913 		/* Then set the optional parameters */
914 		DV_SET(rd_strm, 1);
915 		DV_SET(wr_flow, 1);
916 		DV_SET(rti, 1);
917 		if (min_period == 8)
918 			DV_SET(pcomp_en, 1);
919 	} else {
920 		DV_SET(iu, 0);
921 	}
922 
923 	/* now that we've done all this, actually check the bus
924 	 * signal type (if known).  Some devices are stupid on
925 	 * a SE bus and still claim they can try LVD only settings */
926 	if (i->f->get_signalling)
927 		i->f->get_signalling(shost);
928 	if (spi_signalling(shost) == SPI_SIGNAL_SE ||
929 	    spi_signalling(shost) == SPI_SIGNAL_HVD ||
930 	    !spi_support_dt(starget)) {
931 		DV_SET(dt, 0);
932 	} else {
933 		DV_SET(dt, 1);
934 	}
935 	/* set width last because it will pull all the other
936 	 * parameters down to required values */
937 	DV_SET(width, max_width);
938 
939 	/* Do the read only INQUIRY tests */
940 	spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
941 		       spi_dv_device_compare_inquiry);
942 	/* See if we actually managed to negotiate and sustain DT */
943 	if (i->f->get_dt)
944 		i->f->get_dt(starget);
945 
946 	/* see if the device has an echo buffer.  If it does we can do
947 	 * the SPI pattern write tests.  Because of some broken
948 	 * devices, we *only* try this on a device that has actually
949 	 * negotiated DT */
950 
951 	if (len == -1 && spi_dt(starget))
952 		len = spi_dv_device_get_echo_buffer(sdev, buffer);
953 
954 	if (len <= 0) {
955 		starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
956 		return;
957 	}
958 
959 	if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
960 		starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
961 		len = SPI_MAX_ECHO_BUFFER_SIZE;
962 	}
963 
964 	if (spi_dv_retrain(sdev, buffer, buffer + len,
965 			   spi_dv_device_echo_buffer)
966 	    == SPI_COMPARE_SKIP_TEST) {
967 		/* OK, the stupid drive can't do a write echo buffer
968 		 * test after all, fall back to the read tests */
969 		len = 0;
970 		goto retry;
971 	}
972 }
973 
974 
975 /**	spi_dv_device - Do Domain Validation on the device
976  *	@sdev:		scsi device to validate
977  *
978  *	Performs the domain validation on the given device in the
979  *	current execution thread.  Since DV operations may sleep,
980  *	the current thread must have user context.  Also no SCSI
981  *	related locks that would deadlock I/O issued by the DV may
982  *	be held.
983  */
984 void
985 spi_dv_device(struct scsi_device *sdev)
986 {
987 	struct scsi_target *starget = sdev->sdev_target;
988 	u8 *buffer;
989 	const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
990 
991 	if (unlikely(scsi_device_get(sdev)))
992 		return;
993 
994 	if (unlikely(spi_dv_in_progress(starget)))
995 		return;
996 	spi_dv_in_progress(starget) = 1;
997 
998 	buffer = kzalloc(len, GFP_KERNEL);
999 
1000 	if (unlikely(!buffer))
1001 		goto out_put;
1002 
1003 	/* We need to verify that the actual device will quiesce; the
1004 	 * later target quiesce is just a nice to have */
1005 	if (unlikely(scsi_device_quiesce(sdev)))
1006 		goto out_free;
1007 
1008 	scsi_target_quiesce(starget);
1009 
1010 	spi_dv_pending(starget) = 1;
1011 	mutex_lock(&spi_dv_mutex(starget));
1012 
1013 	starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
1014 
1015 	spi_dv_device_internal(sdev, buffer);
1016 
1017 	starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
1018 
1019 	mutex_unlock(&spi_dv_mutex(starget));
1020 	spi_dv_pending(starget) = 0;
1021 
1022 	scsi_target_resume(starget);
1023 
1024 	spi_initial_dv(starget) = 1;
1025 
1026  out_free:
1027 	kfree(buffer);
1028  out_put:
1029 	spi_dv_in_progress(starget) = 0;
1030 	scsi_device_put(sdev);
1031 }
1032 EXPORT_SYMBOL(spi_dv_device);
1033 
1034 struct work_queue_wrapper {
1035 	struct work_struct	work;
1036 	struct scsi_device	*sdev;
1037 };
1038 
1039 static void
1040 spi_dv_device_work_wrapper(struct work_struct *work)
1041 {
1042 	struct work_queue_wrapper *wqw =
1043 		container_of(work, struct work_queue_wrapper, work);
1044 	struct scsi_device *sdev = wqw->sdev;
1045 
1046 	kfree(wqw);
1047 	spi_dv_device(sdev);
1048 	spi_dv_pending(sdev->sdev_target) = 0;
1049 	scsi_device_put(sdev);
1050 }
1051 
1052 
1053 /**
1054  *	spi_schedule_dv_device - schedule domain validation to occur on the device
1055  *	@sdev:	The device to validate
1056  *
1057  *	Identical to spi_dv_device() above, except that the DV will be
1058  *	scheduled to occur in a workqueue later.  All memory allocations
1059  *	are atomic, so may be called from any context including those holding
1060  *	SCSI locks.
1061  */
1062 void
1063 spi_schedule_dv_device(struct scsi_device *sdev)
1064 {
1065 	struct work_queue_wrapper *wqw =
1066 		kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
1067 
1068 	if (unlikely(!wqw))
1069 		return;
1070 
1071 	if (unlikely(spi_dv_pending(sdev->sdev_target))) {
1072 		kfree(wqw);
1073 		return;
1074 	}
1075 	/* Set pending early (dv_device doesn't check it, only sets it) */
1076 	spi_dv_pending(sdev->sdev_target) = 1;
1077 	if (unlikely(scsi_device_get(sdev))) {
1078 		kfree(wqw);
1079 		spi_dv_pending(sdev->sdev_target) = 0;
1080 		return;
1081 	}
1082 
1083 	INIT_WORK(&wqw->work, spi_dv_device_work_wrapper);
1084 	wqw->sdev = sdev;
1085 
1086 	schedule_work(&wqw->work);
1087 }
1088 EXPORT_SYMBOL(spi_schedule_dv_device);
1089 
1090 /**
1091  * spi_display_xfer_agreement - Print the current target transfer agreement
1092  * @starget: The target for which to display the agreement
1093  *
1094  * Each SPI port is required to maintain a transfer agreement for each
1095  * other port on the bus.  This function prints a one-line summary of
1096  * the current agreement; more detailed information is available in sysfs.
1097  */
1098 void spi_display_xfer_agreement(struct scsi_target *starget)
1099 {
1100 	struct spi_transport_attrs *tp;
1101 	tp = (struct spi_transport_attrs *)&starget->starget_data;
1102 
1103 	if (tp->offset > 0 && tp->period > 0) {
1104 		unsigned int picosec, kb100;
1105 		char *scsi = "FAST-?";
1106 		char tmp[8];
1107 
1108 		if (tp->period <= SPI_STATIC_PPR) {
1109 			picosec = ppr_to_ps[tp->period];
1110 			switch (tp->period) {
1111 				case  7: scsi = "FAST-320"; break;
1112 				case  8: scsi = "FAST-160"; break;
1113 				case  9: scsi = "FAST-80"; break;
1114 				case 10:
1115 				case 11: scsi = "FAST-40"; break;
1116 				case 12: scsi = "FAST-20"; break;
1117 			}
1118 		} else {
1119 			picosec = tp->period * 4000;
1120 			if (tp->period < 25)
1121 				scsi = "FAST-20";
1122 			else if (tp->period < 50)
1123 				scsi = "FAST-10";
1124 			else
1125 				scsi = "FAST-5";
1126 		}
1127 
1128 		kb100 = (10000000 + picosec / 2) / picosec;
1129 		if (tp->width)
1130 			kb100 *= 2;
1131 		sprint_frac(tmp, picosec, 1000);
1132 
1133 		dev_info(&starget->dev,
1134 			 "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1135 			 scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1136 			 tp->dt ? "DT" : "ST",
1137 			 tp->iu ? " IU" : "",
1138 			 tp->qas  ? " QAS" : "",
1139 			 tp->rd_strm ? " RDSTRM" : "",
1140 			 tp->rti ? " RTI" : "",
1141 			 tp->wr_flow ? " WRFLOW" : "",
1142 			 tp->pcomp_en ? " PCOMP" : "",
1143 			 tp->hold_mcs ? " HMCS" : "",
1144 			 tmp, tp->offset);
1145 	} else {
1146 		dev_info(&starget->dev, "%sasynchronous\n",
1147 				tp->width ? "wide " : "");
1148 	}
1149 }
1150 EXPORT_SYMBOL(spi_display_xfer_agreement);
1151 
1152 int spi_populate_width_msg(unsigned char *msg, int width)
1153 {
1154 	msg[0] = EXTENDED_MESSAGE;
1155 	msg[1] = 2;
1156 	msg[2] = EXTENDED_WDTR;
1157 	msg[3] = width;
1158 	return 4;
1159 }
1160 EXPORT_SYMBOL_GPL(spi_populate_width_msg);
1161 
1162 int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
1163 {
1164 	msg[0] = EXTENDED_MESSAGE;
1165 	msg[1] = 3;
1166 	msg[2] = EXTENDED_SDTR;
1167 	msg[3] = period;
1168 	msg[4] = offset;
1169 	return 5;
1170 }
1171 EXPORT_SYMBOL_GPL(spi_populate_sync_msg);
1172 
1173 int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
1174 		int width, int options)
1175 {
1176 	msg[0] = EXTENDED_MESSAGE;
1177 	msg[1] = 6;
1178 	msg[2] = EXTENDED_PPR;
1179 	msg[3] = period;
1180 	msg[4] = 0;
1181 	msg[5] = offset;
1182 	msg[6] = width;
1183 	msg[7] = options;
1184 	return 8;
1185 }
1186 EXPORT_SYMBOL_GPL(spi_populate_ppr_msg);
1187 
1188 #ifdef CONFIG_SCSI_CONSTANTS
1189 static const char * const one_byte_msgs[] = {
1190 /* 0x00 */ "Task Complete", NULL /* Extended Message */, "Save Pointers",
1191 /* 0x03 */ "Restore Pointers", "Disconnect", "Initiator Error",
1192 /* 0x06 */ "Abort Task Set", "Message Reject", "Nop", "Message Parity Error",
1193 /* 0x0a */ "Linked Command Complete", "Linked Command Complete w/flag",
1194 /* 0x0c */ "Target Reset", "Abort Task", "Clear Task Set",
1195 /* 0x0f */ "Initiate Recovery", "Release Recovery",
1196 /* 0x11 */ "Terminate Process", "Continue Task", "Target Transfer Disable",
1197 /* 0x14 */ NULL, NULL, "Clear ACA", "LUN Reset"
1198 };
1199 
1200 static const char * const two_byte_msgs[] = {
1201 /* 0x20 */ "Simple Queue Tag", "Head of Queue Tag", "Ordered Queue Tag",
1202 /* 0x23 */ "Ignore Wide Residue", "ACA"
1203 };
1204 
1205 static const char * const extended_msgs[] = {
1206 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
1207 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
1208 /* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
1209 };
1210 
1211 static void print_nego(const unsigned char *msg, int per, int off, int width)
1212 {
1213 	if (per) {
1214 		char buf[20];
1215 		period_to_str(buf, msg[per]);
1216 		printk("period = %s ns ", buf);
1217 	}
1218 
1219 	if (off)
1220 		printk("offset = %d ", msg[off]);
1221 	if (width)
1222 		printk("width = %d ", 8 << msg[width]);
1223 }
1224 
1225 static void print_ptr(const unsigned char *msg, int msb, const char *desc)
1226 {
1227 	int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
1228 			msg[msb+3];
1229 	printk("%s = %d ", desc, ptr);
1230 }
1231 
1232 int spi_print_msg(const unsigned char *msg)
1233 {
1234 	int len = 1, i;
1235 	if (msg[0] == EXTENDED_MESSAGE) {
1236 		len = 2 + msg[1];
1237 		if (len == 2)
1238 			len += 256;
1239 		if (msg[2] < ARRAY_SIZE(extended_msgs))
1240 			printk ("%s ", extended_msgs[msg[2]]);
1241 		else
1242 			printk ("Extended Message, reserved code (0x%02x) ",
1243 				(int) msg[2]);
1244 		switch (msg[2]) {
1245 		case EXTENDED_MODIFY_DATA_POINTER:
1246 			print_ptr(msg, 3, "pointer");
1247 			break;
1248 		case EXTENDED_SDTR:
1249 			print_nego(msg, 3, 4, 0);
1250 			break;
1251 		case EXTENDED_WDTR:
1252 			print_nego(msg, 0, 0, 3);
1253 			break;
1254 		case EXTENDED_PPR:
1255 			print_nego(msg, 3, 5, 6);
1256 			break;
1257 		case EXTENDED_MODIFY_BIDI_DATA_PTR:
1258 			print_ptr(msg, 3, "out");
1259 			print_ptr(msg, 7, "in");
1260 			break;
1261 		default:
1262 		for (i = 2; i < len; ++i)
1263 			printk("%02x ", msg[i]);
1264 		}
1265 	/* Identify */
1266 	} else if (msg[0] & 0x80) {
1267 		printk("Identify disconnect %sallowed %s %d ",
1268 			(msg[0] & 0x40) ? "" : "not ",
1269 			(msg[0] & 0x20) ? "target routine" : "lun",
1270 			msg[0] & 0x7);
1271 	/* Normal One byte */
1272 	} else if (msg[0] < 0x1f) {
1273 		if (msg[0] < ARRAY_SIZE(one_byte_msgs) && one_byte_msgs[msg[0]])
1274 			printk("%s ", one_byte_msgs[msg[0]]);
1275 		else
1276 			printk("reserved (%02x) ", msg[0]);
1277 	} else if (msg[0] == 0x55) {
1278 		printk("QAS Request ");
1279 	/* Two byte */
1280 	} else if (msg[0] <= 0x2f) {
1281 		if ((msg[0] - 0x20) < ARRAY_SIZE(two_byte_msgs))
1282 			printk("%s %02x ", two_byte_msgs[msg[0] - 0x20],
1283 				msg[1]);
1284 		else
1285 			printk("reserved two byte (%02x %02x) ",
1286 				msg[0], msg[1]);
1287 		len = 2;
1288 	} else
1289 		printk("reserved ");
1290 	return len;
1291 }
1292 EXPORT_SYMBOL(spi_print_msg);
1293 
1294 #else  /* ifndef CONFIG_SCSI_CONSTANTS */
1295 
1296 int spi_print_msg(const unsigned char *msg)
1297 {
1298 	int len = 1, i;
1299 
1300 	if (msg[0] == EXTENDED_MESSAGE) {
1301 		len = 2 + msg[1];
1302 		if (len == 2)
1303 			len += 256;
1304 		for (i = 0; i < len; ++i)
1305 			printk("%02x ", msg[i]);
1306 	/* Identify */
1307 	} else if (msg[0] & 0x80) {
1308 		printk("%02x ", msg[0]);
1309 	/* Normal One byte */
1310 	} else if ((msg[0] < 0x1f) || (msg[0] == 0x55)) {
1311 		printk("%02x ", msg[0]);
1312 	/* Two byte */
1313 	} else if (msg[0] <= 0x2f) {
1314 		printk("%02x %02x", msg[0], msg[1]);
1315 		len = 2;
1316 	} else
1317 		printk("%02x ", msg[0]);
1318 	return len;
1319 }
1320 EXPORT_SYMBOL(spi_print_msg);
1321 #endif /* ! CONFIG_SCSI_CONSTANTS */
1322 
1323 static int spi_device_match(struct attribute_container *cont,
1324 			    struct device *dev)
1325 {
1326 	struct scsi_device *sdev;
1327 	struct Scsi_Host *shost;
1328 	struct spi_internal *i;
1329 
1330 	if (!scsi_is_sdev_device(dev))
1331 		return 0;
1332 
1333 	sdev = to_scsi_device(dev);
1334 	shost = sdev->host;
1335 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1336 	    != &spi_host_class.class)
1337 		return 0;
1338 	/* Note: this class has no device attributes, so it has
1339 	 * no per-HBA allocation and thus we don't need to distinguish
1340 	 * the attribute containers for the device */
1341 	i = to_spi_internal(shost->transportt);
1342 	if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1343 		return 0;
1344 	return 1;
1345 }
1346 
1347 static int spi_target_match(struct attribute_container *cont,
1348 			    struct device *dev)
1349 {
1350 	struct Scsi_Host *shost;
1351 	struct scsi_target *starget;
1352 	struct spi_internal *i;
1353 
1354 	if (!scsi_is_target_device(dev))
1355 		return 0;
1356 
1357 	shost = dev_to_shost(dev->parent);
1358 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1359 	    != &spi_host_class.class)
1360 		return 0;
1361 
1362 	i = to_spi_internal(shost->transportt);
1363 	starget = to_scsi_target(dev);
1364 
1365 	if (i->f->deny_binding && i->f->deny_binding(starget))
1366 		return 0;
1367 
1368 	return &i->t.target_attrs.ac == cont;
1369 }
1370 
1371 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1372 			       "spi_transport",
1373 			       spi_setup_transport_attrs,
1374 			       NULL,
1375 			       spi_target_configure);
1376 
1377 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1378 				    spi_device_match,
1379 				    spi_device_configure);
1380 
1381 static struct attribute *host_attributes[] = {
1382 	&dev_attr_signalling.attr,
1383 	NULL
1384 };
1385 
1386 static struct attribute_group host_attribute_group = {
1387 	.attrs = host_attributes,
1388 };
1389 
1390 static int spi_host_configure(struct transport_container *tc,
1391 			      struct device *dev,
1392 			      struct device *cdev)
1393 {
1394 	struct kobject *kobj = &cdev->kobj;
1395 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1396 	struct spi_internal *si = to_spi_internal(shost->transportt);
1397 	struct attribute *attr = &dev_attr_signalling.attr;
1398 	int rc = 0;
1399 
1400 	if (si->f->set_signalling)
1401 		rc = sysfs_chmod_file(kobj, attr, attr->mode | S_IWUSR);
1402 
1403 	return rc;
1404 }
1405 
1406 /* returns true if we should be showing the variable.  Also
1407  * overloads the return by setting 1<<1 if the attribute should
1408  * be writeable */
1409 #define TARGET_ATTRIBUTE_HELPER(name) \
1410 	(si->f->show_##name ? S_IRUGO : 0) | \
1411 	(si->f->set_##name ? S_IWUSR : 0)
1412 
1413 static mode_t target_attribute_is_visible(struct kobject *kobj,
1414 					  struct attribute *attr, int i)
1415 {
1416 	struct device *cdev = container_of(kobj, struct device, kobj);
1417 	struct scsi_target *starget = transport_class_to_starget(cdev);
1418 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1419 	struct spi_internal *si = to_spi_internal(shost->transportt);
1420 
1421 	if (attr == &dev_attr_period.attr &&
1422 	    spi_support_sync(starget))
1423 		return TARGET_ATTRIBUTE_HELPER(period);
1424 	else if (attr == &dev_attr_min_period.attr &&
1425 		 spi_support_sync(starget))
1426 		return TARGET_ATTRIBUTE_HELPER(period);
1427 	else if (attr == &dev_attr_offset.attr &&
1428 		 spi_support_sync(starget))
1429 		return TARGET_ATTRIBUTE_HELPER(offset);
1430 	else if (attr == &dev_attr_max_offset.attr &&
1431 		 spi_support_sync(starget))
1432 		return TARGET_ATTRIBUTE_HELPER(offset);
1433 	else if (attr == &dev_attr_width.attr &&
1434 		 spi_support_wide(starget))
1435 		return TARGET_ATTRIBUTE_HELPER(width);
1436 	else if (attr == &dev_attr_max_width.attr &&
1437 		 spi_support_wide(starget))
1438 		return TARGET_ATTRIBUTE_HELPER(width);
1439 	else if (attr == &dev_attr_iu.attr &&
1440 		 spi_support_ius(starget))
1441 		return TARGET_ATTRIBUTE_HELPER(iu);
1442 	else if (attr == &dev_attr_max_iu.attr &&
1443 		 spi_support_ius(starget))
1444 		return TARGET_ATTRIBUTE_HELPER(iu);
1445 	else if (attr == &dev_attr_dt.attr &&
1446 		 spi_support_dt(starget))
1447 		return TARGET_ATTRIBUTE_HELPER(dt);
1448 	else if (attr == &dev_attr_qas.attr &&
1449 		 spi_support_qas(starget))
1450 		return TARGET_ATTRIBUTE_HELPER(qas);
1451 	else if (attr == &dev_attr_max_qas.attr &&
1452 		 spi_support_qas(starget))
1453 		return TARGET_ATTRIBUTE_HELPER(qas);
1454 	else if (attr == &dev_attr_wr_flow.attr &&
1455 		 spi_support_ius(starget))
1456 		return TARGET_ATTRIBUTE_HELPER(wr_flow);
1457 	else if (attr == &dev_attr_rd_strm.attr &&
1458 		 spi_support_ius(starget))
1459 		return TARGET_ATTRIBUTE_HELPER(rd_strm);
1460 	else if (attr == &dev_attr_rti.attr &&
1461 		 spi_support_ius(starget))
1462 		return TARGET_ATTRIBUTE_HELPER(rti);
1463 	else if (attr == &dev_attr_pcomp_en.attr &&
1464 		 spi_support_ius(starget))
1465 		return TARGET_ATTRIBUTE_HELPER(pcomp_en);
1466 	else if (attr == &dev_attr_hold_mcs.attr &&
1467 		 spi_support_ius(starget))
1468 		return TARGET_ATTRIBUTE_HELPER(hold_mcs);
1469 	else if (attr == &dev_attr_revalidate.attr)
1470 		return S_IWUSR;
1471 
1472 	return 0;
1473 }
1474 
1475 static struct attribute *target_attributes[] = {
1476 	&dev_attr_period.attr,
1477 	&dev_attr_min_period.attr,
1478 	&dev_attr_offset.attr,
1479 	&dev_attr_max_offset.attr,
1480 	&dev_attr_width.attr,
1481 	&dev_attr_max_width.attr,
1482 	&dev_attr_iu.attr,
1483 	&dev_attr_max_iu.attr,
1484 	&dev_attr_dt.attr,
1485 	&dev_attr_qas.attr,
1486 	&dev_attr_max_qas.attr,
1487 	&dev_attr_wr_flow.attr,
1488 	&dev_attr_rd_strm.attr,
1489 	&dev_attr_rti.attr,
1490 	&dev_attr_pcomp_en.attr,
1491 	&dev_attr_hold_mcs.attr,
1492 	&dev_attr_revalidate.attr,
1493 	NULL
1494 };
1495 
1496 static struct attribute_group target_attribute_group = {
1497 	.attrs = target_attributes,
1498 	.is_visible = target_attribute_is_visible,
1499 };
1500 
1501 static int spi_target_configure(struct transport_container *tc,
1502 				struct device *dev,
1503 				struct device *cdev)
1504 {
1505 	struct kobject *kobj = &cdev->kobj;
1506 
1507 	/* force an update based on parameters read from the device */
1508 	sysfs_update_group(kobj, &target_attribute_group);
1509 
1510 	return 0;
1511 }
1512 
1513 struct scsi_transport_template *
1514 spi_attach_transport(struct spi_function_template *ft)
1515 {
1516 	struct spi_internal *i = kzalloc(sizeof(struct spi_internal),
1517 					 GFP_KERNEL);
1518 
1519 	if (unlikely(!i))
1520 		return NULL;
1521 
1522 	i->t.target_attrs.ac.class = &spi_transport_class.class;
1523 	i->t.target_attrs.ac.grp = &target_attribute_group;
1524 	i->t.target_attrs.ac.match = spi_target_match;
1525 	transport_container_register(&i->t.target_attrs);
1526 	i->t.target_size = sizeof(struct spi_transport_attrs);
1527 	i->t.host_attrs.ac.class = &spi_host_class.class;
1528 	i->t.host_attrs.ac.grp = &host_attribute_group;
1529 	i->t.host_attrs.ac.match = spi_host_match;
1530 	transport_container_register(&i->t.host_attrs);
1531 	i->t.host_size = sizeof(struct spi_host_attrs);
1532 	i->f = ft;
1533 
1534 	return &i->t;
1535 }
1536 EXPORT_SYMBOL(spi_attach_transport);
1537 
1538 void spi_release_transport(struct scsi_transport_template *t)
1539 {
1540 	struct spi_internal *i = to_spi_internal(t);
1541 
1542 	transport_container_unregister(&i->t.target_attrs);
1543 	transport_container_unregister(&i->t.host_attrs);
1544 
1545 	kfree(i);
1546 }
1547 EXPORT_SYMBOL(spi_release_transport);
1548 
1549 static __init int spi_transport_init(void)
1550 {
1551 	int error = scsi_dev_info_add_list(SCSI_DEVINFO_SPI,
1552 					   "SCSI Parallel Transport Class");
1553 	if (!error) {
1554 		int i;
1555 
1556 		for (i = 0; spi_static_device_list[i].vendor; i++)
1557 			scsi_dev_info_list_add_keyed(1,	/* compatible */
1558 						     spi_static_device_list[i].vendor,
1559 						     spi_static_device_list[i].model,
1560 						     NULL,
1561 						     spi_static_device_list[i].flags,
1562 						     SCSI_DEVINFO_SPI);
1563 	}
1564 
1565 	error = transport_class_register(&spi_transport_class);
1566 	if (error)
1567 		return error;
1568 	error = anon_transport_class_register(&spi_device_class);
1569 	return transport_class_register(&spi_host_class);
1570 }
1571 
1572 static void __exit spi_transport_exit(void)
1573 {
1574 	transport_class_unregister(&spi_transport_class);
1575 	anon_transport_class_unregister(&spi_device_class);
1576 	transport_class_unregister(&spi_host_class);
1577 	scsi_dev_info_remove_list(SCSI_DEVINFO_SPI);
1578 }
1579 
1580 MODULE_AUTHOR("Martin Hicks");
1581 MODULE_DESCRIPTION("SPI Transport Attributes");
1582 MODULE_LICENSE("GPL");
1583 
1584 module_init(spi_transport_init);
1585 module_exit(spi_transport_exit);
1586