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