xref: /linux/drivers/scsi/scsi_transport_spi.c (revision a7edd0e676d51145ae634a2acf7a447e319200fa)
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 <scsi/scsi.h>
28 #include "scsi_priv.h"
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_transport_spi.h>
35 
36 #define SPI_NUM_ATTRS 14	/* increase this if you add attributes */
37 #define SPI_OTHER_ATTRS 1	/* Increase this if you add "always
38 				 * on" attributes */
39 #define SPI_HOST_ATTRS	1
40 
41 #define SPI_MAX_ECHO_BUFFER_SIZE	4096
42 
43 #define DV_LOOPS	3
44 #define DV_TIMEOUT	(10*HZ)
45 #define DV_RETRIES	3	/* should only need at most
46 				 * two cc/ua clears */
47 
48 /* Private data accessors (keep these out of the header file) */
49 #define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
50 #define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
51 
52 struct spi_internal {
53 	struct scsi_transport_template t;
54 	struct spi_function_template *f;
55 	/* The actual attributes */
56 	struct class_device_attribute private_attrs[SPI_NUM_ATTRS];
57 	/* The array of null terminated pointers to attributes
58 	 * needed by scsi_sysfs.c */
59 	struct class_device_attribute *attrs[SPI_NUM_ATTRS + SPI_OTHER_ATTRS + 1];
60 	struct class_device_attribute private_host_attrs[SPI_HOST_ATTRS];
61 	struct class_device_attribute *host_attrs[SPI_HOST_ATTRS + 1];
62 };
63 
64 #define to_spi_internal(tmpl)	container_of(tmpl, struct spi_internal, t)
65 
66 static const int ppr_to_ps[] = {
67 	/* The PPR values 0-6 are reserved, fill them in when
68 	 * the committee defines them */
69 	-1,			/* 0x00 */
70 	-1,			/* 0x01 */
71 	-1,			/* 0x02 */
72 	-1,			/* 0x03 */
73 	-1,			/* 0x04 */
74 	-1,			/* 0x05 */
75 	-1,			/* 0x06 */
76 	 3125,			/* 0x07 */
77 	 6250,			/* 0x08 */
78 	12500,			/* 0x09 */
79 	25000,			/* 0x0a */
80 	30300,			/* 0x0b */
81 	50000,			/* 0x0c */
82 };
83 /* The PPR values at which you calculate the period in ns by multiplying
84  * by 4 */
85 #define SPI_STATIC_PPR	0x0c
86 
87 static int sprint_frac(char *dest, int value, int denom)
88 {
89 	int frac = value % denom;
90 	int result = sprintf(dest, "%d", value / denom);
91 
92 	if (frac == 0)
93 		return result;
94 	dest[result++] = '.';
95 
96 	do {
97 		denom /= 10;
98 		sprintf(dest + result, "%d", frac / denom);
99 		result++;
100 		frac %= denom;
101 	} while (frac);
102 
103 	dest[result++] = '\0';
104 	return result;
105 }
106 
107 static int spi_execute(struct scsi_device *sdev, const void *cmd,
108 		       enum dma_data_direction dir,
109 		       void *buffer, unsigned bufflen,
110 		       struct scsi_sense_hdr *sshdr)
111 {
112 	int i, result;
113 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
114 
115 	for(i = 0; i < DV_RETRIES; i++) {
116 		result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
117 				      sense, DV_TIMEOUT, /* retries */ 1,
118 				      REQ_FAILFAST);
119 		if (result & DRIVER_SENSE) {
120 			struct scsi_sense_hdr sshdr_tmp;
121 			if (!sshdr)
122 				sshdr = &sshdr_tmp;
123 
124 			if (scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE,
125 						 sshdr)
126 			    && sshdr->sense_key == UNIT_ATTENTION)
127 				continue;
128 		}
129 		break;
130 	}
131 	return result;
132 }
133 
134 static struct {
135 	enum spi_signal_type	value;
136 	char			*name;
137 } signal_types[] = {
138 	{ SPI_SIGNAL_UNKNOWN, "unknown" },
139 	{ SPI_SIGNAL_SE, "SE" },
140 	{ SPI_SIGNAL_LVD, "LVD" },
141 	{ SPI_SIGNAL_HVD, "HVD" },
142 };
143 
144 static inline const char *spi_signal_to_string(enum spi_signal_type type)
145 {
146 	int i;
147 
148 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
149 		if (type == signal_types[i].value)
150 			return signal_types[i].name;
151 	}
152 	return NULL;
153 }
154 static inline enum spi_signal_type spi_signal_to_value(const char *name)
155 {
156 	int i, len;
157 
158 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
159 		len =  strlen(signal_types[i].name);
160 		if (strncmp(name, signal_types[i].name, len) == 0 &&
161 		    (name[len] == '\n' || name[len] == '\0'))
162 			return signal_types[i].value;
163 	}
164 	return SPI_SIGNAL_UNKNOWN;
165 }
166 
167 static int spi_host_setup(struct transport_container *tc, struct device *dev,
168 			  struct class_device *cdev)
169 {
170 	struct Scsi_Host *shost = dev_to_shost(dev);
171 
172 	spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
173 
174 	return 0;
175 }
176 
177 static DECLARE_TRANSPORT_CLASS(spi_host_class,
178 			       "spi_host",
179 			       spi_host_setup,
180 			       NULL,
181 			       NULL);
182 
183 static int spi_host_match(struct attribute_container *cont,
184 			  struct device *dev)
185 {
186 	struct Scsi_Host *shost;
187 	struct spi_internal *i;
188 
189 	if (!scsi_is_host_device(dev))
190 		return 0;
191 
192 	shost = dev_to_shost(dev);
193 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
194 	    != &spi_host_class.class)
195 		return 0;
196 
197 	i = to_spi_internal(shost->transportt);
198 
199 	return &i->t.host_attrs.ac == cont;
200 }
201 
202 static int spi_device_configure(struct transport_container *tc,
203 				struct device *dev,
204 				struct class_device *cdev)
205 {
206 	struct scsi_device *sdev = to_scsi_device(dev);
207 	struct scsi_target *starget = sdev->sdev_target;
208 
209 	/* Populate the target capability fields with the values
210 	 * gleaned from the device inquiry */
211 
212 	spi_support_sync(starget) = scsi_device_sync(sdev);
213 	spi_support_wide(starget) = scsi_device_wide(sdev);
214 	spi_support_dt(starget) = scsi_device_dt(sdev);
215 	spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
216 	spi_support_ius(starget) = scsi_device_ius(sdev);
217 	spi_support_qas(starget) = scsi_device_qas(sdev);
218 
219 	return 0;
220 }
221 
222 static int spi_setup_transport_attrs(struct transport_container *tc,
223 				     struct device *dev,
224 				     struct class_device *cdev)
225 {
226 	struct scsi_target *starget = to_scsi_target(dev);
227 
228 	spi_period(starget) = -1;	/* illegal value */
229 	spi_min_period(starget) = 0;
230 	spi_offset(starget) = 0;	/* async */
231 	spi_max_offset(starget) = 255;
232 	spi_width(starget) = 0;	/* narrow */
233 	spi_max_width(starget) = 1;
234 	spi_iu(starget) = 0;	/* no IU */
235 	spi_dt(starget) = 0;	/* ST */
236 	spi_qas(starget) = 0;
237 	spi_wr_flow(starget) = 0;
238 	spi_rd_strm(starget) = 0;
239 	spi_rti(starget) = 0;
240 	spi_pcomp_en(starget) = 0;
241 	spi_hold_mcs(starget) = 0;
242 	spi_dv_pending(starget) = 0;
243 	spi_dv_in_progress(starget) = 0;
244 	spi_initial_dv(starget) = 0;
245 	mutex_init(&spi_dv_mutex(starget));
246 
247 	return 0;
248 }
249 
250 #define spi_transport_show_simple(field, format_string)			\
251 									\
252 static ssize_t								\
253 show_spi_transport_##field(struct class_device *cdev, char *buf)	\
254 {									\
255 	struct scsi_target *starget = transport_class_to_starget(cdev);	\
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 class_device *cdev, const char *buf, \
266 			    size_t count)				\
267 {									\
268 	int val;							\
269 	struct scsi_target *starget = transport_class_to_starget(cdev);	\
270 	struct spi_transport_attrs *tp;					\
271 									\
272 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
273 	val = simple_strtoul(buf, NULL, 0);				\
274 	tp->field = val;						\
275 	return count;							\
276 }
277 
278 #define spi_transport_show_function(field, format_string)		\
279 									\
280 static ssize_t								\
281 show_spi_transport_##field(struct class_device *cdev, char *buf)	\
282 {									\
283 	struct scsi_target *starget = transport_class_to_starget(cdev);	\
284 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
285 	struct spi_transport_attrs *tp;					\
286 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
287 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
288 	if (i->f->get_##field)						\
289 		i->f->get_##field(starget);				\
290 	return snprintf(buf, 20, format_string, tp->field);		\
291 }
292 
293 #define spi_transport_store_function(field, format_string)		\
294 static ssize_t								\
295 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
296 			    size_t count)				\
297 {									\
298 	int val;							\
299 	struct scsi_target *starget = transport_class_to_starget(cdev);	\
300 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
301 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
302 									\
303 	val = simple_strtoul(buf, NULL, 0);				\
304 	i->f->set_##field(starget, val);			\
305 	return count;							\
306 }
307 
308 #define spi_transport_store_max(field, format_string)			\
309 static ssize_t								\
310 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
311 			    size_t count)				\
312 {									\
313 	int val;							\
314 	struct scsi_target *starget = transport_class_to_starget(cdev);	\
315 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
316 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
317 	struct spi_transport_attrs *tp					\
318 		= (struct spi_transport_attrs *)&starget->starget_data;	\
319 									\
320 	val = simple_strtoul(buf, NULL, 0);				\
321 	if (val > tp->max_##field)					\
322 		val = tp->max_##field;					\
323 	i->f->set_##field(starget, val);				\
324 	return count;							\
325 }
326 
327 #define spi_transport_rd_attr(field, format_string)			\
328 	spi_transport_show_function(field, format_string)		\
329 	spi_transport_store_function(field, format_string)		\
330 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,			\
331 			 show_spi_transport_##field,			\
332 			 store_spi_transport_##field);
333 
334 #define spi_transport_simple_attr(field, format_string)			\
335 	spi_transport_show_simple(field, format_string)			\
336 	spi_transport_store_simple(field, format_string)		\
337 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,			\
338 			 show_spi_transport_##field,			\
339 			 store_spi_transport_##field);
340 
341 #define spi_transport_max_attr(field, format_string)			\
342 	spi_transport_show_function(field, format_string)		\
343 	spi_transport_store_max(field, format_string)			\
344 	spi_transport_simple_attr(max_##field, format_string)		\
345 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,			\
346 			 show_spi_transport_##field,			\
347 			 store_spi_transport_##field);
348 
349 /* The Parallel SCSI Tranport Attributes: */
350 spi_transport_max_attr(offset, "%d\n");
351 spi_transport_max_attr(width, "%d\n");
352 spi_transport_rd_attr(iu, "%d\n");
353 spi_transport_rd_attr(dt, "%d\n");
354 spi_transport_rd_attr(qas, "%d\n");
355 spi_transport_rd_attr(wr_flow, "%d\n");
356 spi_transport_rd_attr(rd_strm, "%d\n");
357 spi_transport_rd_attr(rti, "%d\n");
358 spi_transport_rd_attr(pcomp_en, "%d\n");
359 spi_transport_rd_attr(hold_mcs, "%d\n");
360 
361 /* we only care about the first child device so we return 1 */
362 static int child_iter(struct device *dev, void *data)
363 {
364 	struct scsi_device *sdev = to_scsi_device(dev);
365 
366 	spi_dv_device(sdev);
367 	return 1;
368 }
369 
370 static ssize_t
371 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
372 {
373 	struct scsi_target *starget = transport_class_to_starget(cdev);
374 
375 	device_for_each_child(&starget->dev, NULL, child_iter);
376 	return count;
377 }
378 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
379 
380 /* Translate the period into ns according to the current spec
381  * for SDTR/PPR messages */
382 static int period_to_str(char *buf, int period)
383 {
384 	int len, picosec;
385 
386 	if (period < 0 || period > 0xff) {
387 		picosec = -1;
388 	} else if (period <= SPI_STATIC_PPR) {
389 		picosec = ppr_to_ps[period];
390 	} else {
391 		picosec = period * 4000;
392 	}
393 
394 	if (picosec == -1) {
395 		len = sprintf(buf, "reserved");
396 	} else {
397 		len = sprint_frac(buf, picosec, 1000);
398 	}
399 
400 	return len;
401 }
402 
403 static ssize_t
404 show_spi_transport_period_helper(char *buf, int period)
405 {
406 	int len = period_to_str(buf, period);
407 	buf[len++] = '\n';
408 	buf[len] = '\0';
409 	return len;
410 }
411 
412 static ssize_t
413 store_spi_transport_period_helper(struct class_device *cdev, const char *buf,
414 				  size_t count, int *periodp)
415 {
416 	int j, picosec, period = -1;
417 	char *endp;
418 
419 	picosec = simple_strtoul(buf, &endp, 10) * 1000;
420 	if (*endp == '.') {
421 		int mult = 100;
422 		do {
423 			endp++;
424 			if (!isdigit(*endp))
425 				break;
426 			picosec += (*endp - '0') * mult;
427 			mult /= 10;
428 		} while (mult > 0);
429 	}
430 
431 	for (j = 0; j <= SPI_STATIC_PPR; j++) {
432 		if (ppr_to_ps[j] < picosec)
433 			continue;
434 		period = j;
435 		break;
436 	}
437 
438 	if (period == -1)
439 		period = picosec / 4000;
440 
441 	if (period > 0xff)
442 		period = 0xff;
443 
444 	*periodp = period;
445 
446 	return count;
447 }
448 
449 static ssize_t
450 show_spi_transport_period(struct class_device *cdev, char *buf)
451 {
452 	struct scsi_target *starget = transport_class_to_starget(cdev);
453 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
454 	struct spi_internal *i = to_spi_internal(shost->transportt);
455 	struct spi_transport_attrs *tp =
456 		(struct spi_transport_attrs *)&starget->starget_data;
457 
458 	if (i->f->get_period)
459 		i->f->get_period(starget);
460 
461 	return show_spi_transport_period_helper(buf, tp->period);
462 }
463 
464 static ssize_t
465 store_spi_transport_period(struct class_device *cdev, const char *buf,
466 			    size_t count)
467 {
468 	struct scsi_target *starget = transport_class_to_starget(cdev);
469 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
470 	struct spi_internal *i = to_spi_internal(shost->transportt);
471 	struct spi_transport_attrs *tp =
472 		(struct spi_transport_attrs *)&starget->starget_data;
473 	int period, retval;
474 
475 	retval = store_spi_transport_period_helper(cdev, buf, count, &period);
476 
477 	if (period < tp->min_period)
478 		period = tp->min_period;
479 
480 	i->f->set_period(starget, period);
481 
482 	return retval;
483 }
484 
485 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
486 			 show_spi_transport_period,
487 			 store_spi_transport_period);
488 
489 static ssize_t
490 show_spi_transport_min_period(struct class_device *cdev, char *buf)
491 {
492 	struct scsi_target *starget = transport_class_to_starget(cdev);
493 	struct spi_transport_attrs *tp =
494 		(struct spi_transport_attrs *)&starget->starget_data;
495 
496 	return show_spi_transport_period_helper(buf, tp->min_period);
497 }
498 
499 static ssize_t
500 store_spi_transport_min_period(struct class_device *cdev, const char *buf,
501 			    size_t count)
502 {
503 	struct scsi_target *starget = transport_class_to_starget(cdev);
504 	struct spi_transport_attrs *tp =
505 		(struct spi_transport_attrs *)&starget->starget_data;
506 
507 	return store_spi_transport_period_helper(cdev, buf, count,
508 						 &tp->min_period);
509 }
510 
511 
512 static CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR,
513 			 show_spi_transport_min_period,
514 			 store_spi_transport_min_period);
515 
516 
517 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
518 {
519 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
520 	struct spi_internal *i = to_spi_internal(shost->transportt);
521 
522 	if (i->f->get_signalling)
523 		i->f->get_signalling(shost);
524 
525 	return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
526 }
527 static ssize_t store_spi_host_signalling(struct class_device *cdev,
528 					 const char *buf, size_t count)
529 {
530 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
531 	struct spi_internal *i = to_spi_internal(shost->transportt);
532 	enum spi_signal_type type = spi_signal_to_value(buf);
533 
534 	if (type != SPI_SIGNAL_UNKNOWN)
535 		i->f->set_signalling(shost, type);
536 
537 	return count;
538 }
539 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
540 			 show_spi_host_signalling,
541 			 store_spi_host_signalling);
542 
543 #define DV_SET(x, y)			\
544 	if(i->f->set_##x)		\
545 		i->f->set_##x(sdev->sdev_target, y)
546 
547 enum spi_compare_returns {
548 	SPI_COMPARE_SUCCESS,
549 	SPI_COMPARE_FAILURE,
550 	SPI_COMPARE_SKIP_TEST,
551 };
552 
553 
554 /* This is for read/write Domain Validation:  If the device supports
555  * an echo buffer, we do read/write tests to it */
556 static enum spi_compare_returns
557 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
558 			  u8 *ptr, const int retries)
559 {
560 	int len = ptr - buffer;
561 	int j, k, r, result;
562 	unsigned int pattern = 0x0000ffff;
563 	struct scsi_sense_hdr sshdr;
564 
565 	const char spi_write_buffer[] = {
566 		WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
567 	};
568 	const char spi_read_buffer[] = {
569 		READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
570 	};
571 
572 	/* set up the pattern buffer.  Doesn't matter if we spill
573 	 * slightly beyond since that's where the read buffer is */
574 	for (j = 0; j < len; ) {
575 
576 		/* fill the buffer with counting (test a) */
577 		for ( ; j < min(len, 32); j++)
578 			buffer[j] = j;
579 		k = j;
580 		/* fill the buffer with alternating words of 0x0 and
581 		 * 0xffff (test b) */
582 		for ( ; j < min(len, k + 32); j += 2) {
583 			u16 *word = (u16 *)&buffer[j];
584 
585 			*word = (j & 0x02) ? 0x0000 : 0xffff;
586 		}
587 		k = j;
588 		/* fill with crosstalk (alternating 0x5555 0xaaa)
589                  * (test c) */
590 		for ( ; j < min(len, k + 32); j += 2) {
591 			u16 *word = (u16 *)&buffer[j];
592 
593 			*word = (j & 0x02) ? 0x5555 : 0xaaaa;
594 		}
595 		k = j;
596 		/* fill with shifting bits (test d) */
597 		for ( ; j < min(len, k + 32); j += 4) {
598 			u32 *word = (unsigned int *)&buffer[j];
599 			u32 roll = (pattern & 0x80000000) ? 1 : 0;
600 
601 			*word = pattern;
602 			pattern = (pattern << 1) | roll;
603 		}
604 		/* don't bother with random data (test e) */
605 	}
606 
607 	for (r = 0; r < retries; r++) {
608 		result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
609 				     buffer, len, &sshdr);
610 		if(result || !scsi_device_online(sdev)) {
611 
612 			scsi_device_set_state(sdev, SDEV_QUIESCE);
613 			if (scsi_sense_valid(&sshdr)
614 			    && sshdr.sense_key == ILLEGAL_REQUEST
615 			    /* INVALID FIELD IN CDB */
616 			    && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
617 				/* This would mean that the drive lied
618 				 * to us about supporting an echo
619 				 * buffer (unfortunately some Western
620 				 * Digital drives do precisely this)
621 				 */
622 				return SPI_COMPARE_SKIP_TEST;
623 
624 
625 			sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
626 			return SPI_COMPARE_FAILURE;
627 		}
628 
629 		memset(ptr, 0, len);
630 		spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
631 			    ptr, len, NULL);
632 		scsi_device_set_state(sdev, SDEV_QUIESCE);
633 
634 		if (memcmp(buffer, ptr, len) != 0)
635 			return SPI_COMPARE_FAILURE;
636 	}
637 	return SPI_COMPARE_SUCCESS;
638 }
639 
640 /* This is for the simplest form of Domain Validation: a read test
641  * on the inquiry data from the device */
642 static enum spi_compare_returns
643 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
644 			      u8 *ptr, const int retries)
645 {
646 	int r, result;
647 	const int len = sdev->inquiry_len;
648 	const char spi_inquiry[] = {
649 		INQUIRY, 0, 0, 0, len, 0
650 	};
651 
652 	for (r = 0; r < retries; r++) {
653 		memset(ptr, 0, len);
654 
655 		result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
656 				     ptr, len, NULL);
657 
658 		if(result || !scsi_device_online(sdev)) {
659 			scsi_device_set_state(sdev, SDEV_QUIESCE);
660 			return SPI_COMPARE_FAILURE;
661 		}
662 
663 		/* If we don't have the inquiry data already, the
664 		 * first read gets it */
665 		if (ptr == buffer) {
666 			ptr += len;
667 			--r;
668 			continue;
669 		}
670 
671 		if (memcmp(buffer, ptr, len) != 0)
672 			/* failure */
673 			return SPI_COMPARE_FAILURE;
674 	}
675 	return SPI_COMPARE_SUCCESS;
676 }
677 
678 static enum spi_compare_returns
679 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
680 	       enum spi_compare_returns
681 	       (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
682 {
683 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
684 	struct scsi_target *starget = sdev->sdev_target;
685 	int period = 0, prevperiod = 0;
686 	enum spi_compare_returns retval;
687 
688 
689 	for (;;) {
690 		int newperiod;
691 		retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
692 
693 		if (retval == SPI_COMPARE_SUCCESS
694 		    || retval == SPI_COMPARE_SKIP_TEST)
695 			break;
696 
697 		/* OK, retrain, fallback */
698 		if (i->f->get_iu)
699 			i->f->get_iu(starget);
700 		if (i->f->get_qas)
701 			i->f->get_qas(starget);
702 		if (i->f->get_period)
703 			i->f->get_period(sdev->sdev_target);
704 
705 		/* Here's the fallback sequence; first try turning off
706 		 * IU, then QAS (if we can control them), then finally
707 		 * fall down the periods */
708 		if (i->f->set_iu && spi_iu(starget)) {
709 			starget_printk(KERN_ERR, starget, "Domain Validation Disabing Information Units\n");
710 			DV_SET(iu, 0);
711 		} else if (i->f->set_qas && spi_qas(starget)) {
712 			starget_printk(KERN_ERR, starget, "Domain Validation Disabing Quick Arbitration and Selection\n");
713 			DV_SET(qas, 0);
714 		} else {
715 			newperiod = spi_period(starget);
716 			period = newperiod > period ? newperiod : period;
717 			if (period < 0x0d)
718 				period++;
719 			else
720 				period += period >> 1;
721 
722 			if (unlikely(period > 0xff || period == prevperiod)) {
723 				/* Total failure; set to async and return */
724 				starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
725 				DV_SET(offset, 0);
726 				return SPI_COMPARE_FAILURE;
727 			}
728 			starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
729 			DV_SET(period, period);
730 			prevperiod = period;
731 		}
732 	}
733 	return retval;
734 }
735 
736 static int
737 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
738 {
739 	int l, result;
740 
741 	/* first off do a test unit ready.  This can error out
742 	 * because of reservations or some other reason.  If it
743 	 * fails, the device won't let us write to the echo buffer
744 	 * so just return failure */
745 
746 	const char spi_test_unit_ready[] = {
747 		TEST_UNIT_READY, 0, 0, 0, 0, 0
748 	};
749 
750 	const char spi_read_buffer_descriptor[] = {
751 		READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
752 	};
753 
754 
755 	/* We send a set of three TURs to clear any outstanding
756 	 * unit attention conditions if they exist (Otherwise the
757 	 * buffer tests won't be happy).  If the TUR still fails
758 	 * (reservation conflict, device not ready, etc) just
759 	 * skip the write tests */
760 	for (l = 0; ; l++) {
761 		result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE,
762 				     NULL, 0, NULL);
763 
764 		if(result) {
765 			if(l >= 3)
766 				return 0;
767 		} else {
768 			/* TUR succeeded */
769 			break;
770 		}
771 	}
772 
773 	result = spi_execute(sdev, spi_read_buffer_descriptor,
774 			     DMA_FROM_DEVICE, buffer, 4, NULL);
775 
776 	if (result)
777 		/* Device has no echo buffer */
778 		return 0;
779 
780 	return buffer[3] + ((buffer[2] & 0x1f) << 8);
781 }
782 
783 static void
784 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
785 {
786 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
787 	struct scsi_target *starget = sdev->sdev_target;
788 	struct Scsi_Host *shost = sdev->host;
789 	int len = sdev->inquiry_len;
790 	/* first set us up for narrow async */
791 	DV_SET(offset, 0);
792 	DV_SET(width, 0);
793 
794 	if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
795 	    != SPI_COMPARE_SUCCESS) {
796 		starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
797 		/* FIXME: should probably offline the device here? */
798 		return;
799 	}
800 
801 	/* test width */
802 	if (i->f->set_width && spi_max_width(starget) &&
803 	    scsi_device_wide(sdev)) {
804 		i->f->set_width(starget, 1);
805 
806 		if (spi_dv_device_compare_inquiry(sdev, buffer,
807 						   buffer + len,
808 						   DV_LOOPS)
809 		    != SPI_COMPARE_SUCCESS) {
810 			starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
811 			i->f->set_width(starget, 0);
812 		}
813 	}
814 
815 	if (!i->f->set_period)
816 		return;
817 
818 	/* device can't handle synchronous */
819 	if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
820 		return;
821 
822 	/* len == -1 is the signal that we need to ascertain the
823 	 * presence of an echo buffer before trying to use it.  len ==
824 	 * 0 means we don't have an echo buffer */
825 	len = -1;
826 
827  retry:
828 
829 	/* now set up to the maximum */
830 	DV_SET(offset, spi_max_offset(starget));
831 	DV_SET(period, spi_min_period(starget));
832 	/* try QAS requests; this should be harmless to set if the
833 	 * target supports it */
834 	if (scsi_device_qas(sdev)) {
835 		DV_SET(qas, 1);
836 	} else {
837 		DV_SET(qas, 0);
838 	}
839 
840 	if (scsi_device_ius(sdev) && spi_min_period(starget) < 9) {
841 		/* This u320 (or u640). Set IU transfers */
842 		DV_SET(iu, 1);
843 		/* Then set the optional parameters */
844 		DV_SET(rd_strm, 1);
845 		DV_SET(wr_flow, 1);
846 		DV_SET(rti, 1);
847 		if (spi_min_period(starget) == 8)
848 			DV_SET(pcomp_en, 1);
849 	} else {
850 		DV_SET(iu, 0);
851 	}
852 
853 	/* now that we've done all this, actually check the bus
854 	 * signal type (if known).  Some devices are stupid on
855 	 * a SE bus and still claim they can try LVD only settings */
856 	if (i->f->get_signalling)
857 		i->f->get_signalling(shost);
858 	if (spi_signalling(shost) == SPI_SIGNAL_SE ||
859 	    spi_signalling(shost) == SPI_SIGNAL_HVD ||
860 	    !scsi_device_dt(sdev)) {
861 		DV_SET(dt, 0);
862 	} else {
863 		DV_SET(dt, 1);
864 	}
865 	/* Do the read only INQUIRY tests */
866 	spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
867 		       spi_dv_device_compare_inquiry);
868 	/* See if we actually managed to negotiate and sustain DT */
869 	if (i->f->get_dt)
870 		i->f->get_dt(starget);
871 
872 	/* see if the device has an echo buffer.  If it does we can do
873 	 * the SPI pattern write tests.  Because of some broken
874 	 * devices, we *only* try this on a device that has actually
875 	 * negotiated DT */
876 
877 	if (len == -1 && spi_dt(starget))
878 		len = spi_dv_device_get_echo_buffer(sdev, buffer);
879 
880 	if (len <= 0) {
881 		starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
882 		return;
883 	}
884 
885 	if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
886 		starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
887 		len = SPI_MAX_ECHO_BUFFER_SIZE;
888 	}
889 
890 	if (spi_dv_retrain(sdev, buffer, buffer + len,
891 			   spi_dv_device_echo_buffer)
892 	    == SPI_COMPARE_SKIP_TEST) {
893 		/* OK, the stupid drive can't do a write echo buffer
894 		 * test after all, fall back to the read tests */
895 		len = 0;
896 		goto retry;
897 	}
898 }
899 
900 
901 /**	spi_dv_device - Do Domain Validation on the device
902  *	@sdev:		scsi device to validate
903  *
904  *	Performs the domain validation on the given device in the
905  *	current execution thread.  Since DV operations may sleep,
906  *	the current thread must have user context.  Also no SCSI
907  *	related locks that would deadlock I/O issued by the DV may
908  *	be held.
909  */
910 void
911 spi_dv_device(struct scsi_device *sdev)
912 {
913 	struct scsi_target *starget = sdev->sdev_target;
914 	u8 *buffer;
915 	const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
916 
917 	if (unlikely(scsi_device_get(sdev)))
918 		return;
919 
920 	if (unlikely(spi_dv_in_progress(starget)))
921 		return;
922 	spi_dv_in_progress(starget) = 1;
923 
924 	buffer = kzalloc(len, GFP_KERNEL);
925 
926 	if (unlikely(!buffer))
927 		goto out_put;
928 
929 	/* We need to verify that the actual device will quiesce; the
930 	 * later target quiesce is just a nice to have */
931 	if (unlikely(scsi_device_quiesce(sdev)))
932 		goto out_free;
933 
934 	scsi_target_quiesce(starget);
935 
936 	spi_dv_pending(starget) = 1;
937 	mutex_lock(&spi_dv_mutex(starget));
938 
939 	starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
940 
941 	spi_dv_device_internal(sdev, buffer);
942 
943 	starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
944 
945 	mutex_unlock(&spi_dv_mutex(starget));
946 	spi_dv_pending(starget) = 0;
947 
948 	scsi_target_resume(starget);
949 
950 	spi_initial_dv(starget) = 1;
951 
952  out_free:
953 	kfree(buffer);
954  out_put:
955 	spi_dv_in_progress(starget) = 0;
956 	scsi_device_put(sdev);
957 }
958 EXPORT_SYMBOL(spi_dv_device);
959 
960 struct work_queue_wrapper {
961 	struct work_struct	work;
962 	struct scsi_device	*sdev;
963 };
964 
965 static void
966 spi_dv_device_work_wrapper(struct work_struct *work)
967 {
968 	struct work_queue_wrapper *wqw =
969 		container_of(work, struct work_queue_wrapper, work);
970 	struct scsi_device *sdev = wqw->sdev;
971 
972 	kfree(wqw);
973 	spi_dv_device(sdev);
974 	spi_dv_pending(sdev->sdev_target) = 0;
975 	scsi_device_put(sdev);
976 }
977 
978 
979 /**
980  *	spi_schedule_dv_device - schedule domain validation to occur on the device
981  *	@sdev:	The device to validate
982  *
983  *	Identical to spi_dv_device() above, except that the DV will be
984  *	scheduled to occur in a workqueue later.  All memory allocations
985  *	are atomic, so may be called from any context including those holding
986  *	SCSI locks.
987  */
988 void
989 spi_schedule_dv_device(struct scsi_device *sdev)
990 {
991 	struct work_queue_wrapper *wqw =
992 		kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
993 
994 	if (unlikely(!wqw))
995 		return;
996 
997 	if (unlikely(spi_dv_pending(sdev->sdev_target))) {
998 		kfree(wqw);
999 		return;
1000 	}
1001 	/* Set pending early (dv_device doesn't check it, only sets it) */
1002 	spi_dv_pending(sdev->sdev_target) = 1;
1003 	if (unlikely(scsi_device_get(sdev))) {
1004 		kfree(wqw);
1005 		spi_dv_pending(sdev->sdev_target) = 0;
1006 		return;
1007 	}
1008 
1009 	INIT_WORK(&wqw->work, spi_dv_device_work_wrapper);
1010 	wqw->sdev = sdev;
1011 
1012 	schedule_work(&wqw->work);
1013 }
1014 EXPORT_SYMBOL(spi_schedule_dv_device);
1015 
1016 /**
1017  * spi_display_xfer_agreement - Print the current target transfer agreement
1018  * @starget: The target for which to display the agreement
1019  *
1020  * Each SPI port is required to maintain a transfer agreement for each
1021  * other port on the bus.  This function prints a one-line summary of
1022  * the current agreement; more detailed information is available in sysfs.
1023  */
1024 void spi_display_xfer_agreement(struct scsi_target *starget)
1025 {
1026 	struct spi_transport_attrs *tp;
1027 	tp = (struct spi_transport_attrs *)&starget->starget_data;
1028 
1029 	if (tp->offset > 0 && tp->period > 0) {
1030 		unsigned int picosec, kb100;
1031 		char *scsi = "FAST-?";
1032 		char tmp[8];
1033 
1034 		if (tp->period <= SPI_STATIC_PPR) {
1035 			picosec = ppr_to_ps[tp->period];
1036 			switch (tp->period) {
1037 				case  7: scsi = "FAST-320"; break;
1038 				case  8: scsi = "FAST-160"; break;
1039 				case  9: scsi = "FAST-80"; break;
1040 				case 10:
1041 				case 11: scsi = "FAST-40"; break;
1042 				case 12: scsi = "FAST-20"; break;
1043 			}
1044 		} else {
1045 			picosec = tp->period * 4000;
1046 			if (tp->period < 25)
1047 				scsi = "FAST-20";
1048 			else if (tp->period < 50)
1049 				scsi = "FAST-10";
1050 			else
1051 				scsi = "FAST-5";
1052 		}
1053 
1054 		kb100 = (10000000 + picosec / 2) / picosec;
1055 		if (tp->width)
1056 			kb100 *= 2;
1057 		sprint_frac(tmp, picosec, 1000);
1058 
1059 		dev_info(&starget->dev,
1060 			 "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1061 			 scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1062 			 tp->dt ? "DT" : "ST",
1063 			 tp->iu ? " IU" : "",
1064 			 tp->qas  ? " QAS" : "",
1065 			 tp->rd_strm ? " RDSTRM" : "",
1066 			 tp->rti ? " RTI" : "",
1067 			 tp->wr_flow ? " WRFLOW" : "",
1068 			 tp->pcomp_en ? " PCOMP" : "",
1069 			 tp->hold_mcs ? " HMCS" : "",
1070 			 tmp, tp->offset);
1071 	} else {
1072 		dev_info(&starget->dev, "%sasynchronous\n",
1073 				tp->width ? "wide " : "");
1074 	}
1075 }
1076 EXPORT_SYMBOL(spi_display_xfer_agreement);
1077 
1078 int spi_populate_width_msg(unsigned char *msg, int width)
1079 {
1080 	msg[0] = EXTENDED_MESSAGE;
1081 	msg[1] = 2;
1082 	msg[2] = EXTENDED_WDTR;
1083 	msg[3] = width;
1084 	return 4;
1085 }
1086 EXPORT_SYMBOL_GPL(spi_populate_width_msg);
1087 
1088 int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
1089 {
1090 	msg[0] = EXTENDED_MESSAGE;
1091 	msg[1] = 3;
1092 	msg[2] = EXTENDED_SDTR;
1093 	msg[3] = period;
1094 	msg[4] = offset;
1095 	return 5;
1096 }
1097 EXPORT_SYMBOL_GPL(spi_populate_sync_msg);
1098 
1099 int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
1100 		int width, int options)
1101 {
1102 	msg[0] = EXTENDED_MESSAGE;
1103 	msg[1] = 6;
1104 	msg[2] = EXTENDED_PPR;
1105 	msg[3] = period;
1106 	msg[4] = 0;
1107 	msg[5] = offset;
1108 	msg[6] = width;
1109 	msg[7] = options;
1110 	return 8;
1111 }
1112 EXPORT_SYMBOL_GPL(spi_populate_ppr_msg);
1113 
1114 #ifdef CONFIG_SCSI_CONSTANTS
1115 static const char * const one_byte_msgs[] = {
1116 /* 0x00 */ "Task Complete", NULL /* Extended Message */, "Save Pointers",
1117 /* 0x03 */ "Restore Pointers", "Disconnect", "Initiator Error",
1118 /* 0x06 */ "Abort Task Set", "Message Reject", "Nop", "Message Parity Error",
1119 /* 0x0a */ "Linked Command Complete", "Linked Command Complete w/flag",
1120 /* 0x0c */ "Target Reset", "Abort Task", "Clear Task Set",
1121 /* 0x0f */ "Initiate Recovery", "Release Recovery",
1122 /* 0x11 */ "Terminate Process", "Continue Task", "Target Transfer Disable",
1123 /* 0x14 */ NULL, NULL, "Clear ACA", "LUN Reset"
1124 };
1125 
1126 static const char * const two_byte_msgs[] = {
1127 /* 0x20 */ "Simple Queue Tag", "Head of Queue Tag", "Ordered Queue Tag",
1128 /* 0x23 */ "Ignore Wide Residue", "ACA"
1129 };
1130 
1131 static const char * const extended_msgs[] = {
1132 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
1133 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
1134 /* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
1135 };
1136 
1137 static void print_nego(const unsigned char *msg, int per, int off, int width)
1138 {
1139 	if (per) {
1140 		char buf[20];
1141 		period_to_str(buf, msg[per]);
1142 		printk("period = %s ns ", buf);
1143 	}
1144 
1145 	if (off)
1146 		printk("offset = %d ", msg[off]);
1147 	if (width)
1148 		printk("width = %d ", 8 << msg[width]);
1149 }
1150 
1151 static void print_ptr(const unsigned char *msg, int msb, const char *desc)
1152 {
1153 	int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
1154 			msg[msb+3];
1155 	printk("%s = %d ", desc, ptr);
1156 }
1157 
1158 int spi_print_msg(const unsigned char *msg)
1159 {
1160 	int len = 1, i;
1161 	if (msg[0] == EXTENDED_MESSAGE) {
1162 		len = 2 + msg[1];
1163 		if (len == 2)
1164 			len += 256;
1165 		if (msg[2] < ARRAY_SIZE(extended_msgs))
1166 			printk ("%s ", extended_msgs[msg[2]]);
1167 		else
1168 			printk ("Extended Message, reserved code (0x%02x) ",
1169 				(int) msg[2]);
1170 		switch (msg[2]) {
1171 		case EXTENDED_MODIFY_DATA_POINTER:
1172 			print_ptr(msg, 3, "pointer");
1173 			break;
1174 		case EXTENDED_SDTR:
1175 			print_nego(msg, 3, 4, 0);
1176 			break;
1177 		case EXTENDED_WDTR:
1178 			print_nego(msg, 0, 0, 3);
1179 			break;
1180 		case EXTENDED_PPR:
1181 			print_nego(msg, 3, 5, 6);
1182 			break;
1183 		case EXTENDED_MODIFY_BIDI_DATA_PTR:
1184 			print_ptr(msg, 3, "out");
1185 			print_ptr(msg, 7, "in");
1186 			break;
1187 		default:
1188 		for (i = 2; i < len; ++i)
1189 			printk("%02x ", msg[i]);
1190 		}
1191 	/* Identify */
1192 	} else if (msg[0] & 0x80) {
1193 		printk("Identify disconnect %sallowed %s %d ",
1194 			(msg[0] & 0x40) ? "" : "not ",
1195 			(msg[0] & 0x20) ? "target routine" : "lun",
1196 			msg[0] & 0x7);
1197 	/* Normal One byte */
1198 	} else if (msg[0] < 0x1f) {
1199 		if (msg[0] < ARRAY_SIZE(one_byte_msgs) && one_byte_msgs[msg[0]])
1200 			printk("%s ", one_byte_msgs[msg[0]]);
1201 		else
1202 			printk("reserved (%02x) ", msg[0]);
1203 	} else if (msg[0] == 0x55) {
1204 		printk("QAS Request ");
1205 	/* Two byte */
1206 	} else if (msg[0] <= 0x2f) {
1207 		if ((msg[0] - 0x20) < ARRAY_SIZE(two_byte_msgs))
1208 			printk("%s %02x ", two_byte_msgs[msg[0] - 0x20],
1209 				msg[1]);
1210 		else
1211 			printk("reserved two byte (%02x %02x) ",
1212 				msg[0], msg[1]);
1213 		len = 2;
1214 	} else
1215 		printk("reserved ");
1216 	return len;
1217 }
1218 EXPORT_SYMBOL(spi_print_msg);
1219 
1220 #else  /* ifndef CONFIG_SCSI_CONSTANTS */
1221 
1222 int spi_print_msg(const unsigned char *msg)
1223 {
1224 	int len = 1, i;
1225 
1226 	if (msg[0] == EXTENDED_MESSAGE) {
1227 		len = 2 + msg[1];
1228 		if (len == 2)
1229 			len += 256;
1230 		for (i = 0; i < len; ++i)
1231 			printk("%02x ", msg[i]);
1232 	/* Identify */
1233 	} else if (msg[0] & 0x80) {
1234 		printk("%02x ", msg[0]);
1235 	/* Normal One byte */
1236 	} else if ((msg[0] < 0x1f) || (msg[0] == 0x55)) {
1237 		printk("%02x ", msg[0]);
1238 	/* Two byte */
1239 	} else if (msg[0] <= 0x2f) {
1240 		printk("%02x %02x", msg[0], msg[1]);
1241 		len = 2;
1242 	} else
1243 		printk("%02x ", msg[0]);
1244 	return len;
1245 }
1246 EXPORT_SYMBOL(spi_print_msg);
1247 #endif /* ! CONFIG_SCSI_CONSTANTS */
1248 
1249 #define SETUP_ATTRIBUTE(field)						\
1250 	i->private_attrs[count] = class_device_attr_##field;		\
1251 	if (!i->f->set_##field) {					\
1252 		i->private_attrs[count].attr.mode = S_IRUGO;		\
1253 		i->private_attrs[count].store = NULL;			\
1254 	}								\
1255 	i->attrs[count] = &i->private_attrs[count];			\
1256 	if (i->f->show_##field)						\
1257 		count++
1258 
1259 #define SETUP_RELATED_ATTRIBUTE(field, rel_field)			\
1260 	i->private_attrs[count] = class_device_attr_##field;		\
1261 	if (!i->f->set_##rel_field) {					\
1262 		i->private_attrs[count].attr.mode = S_IRUGO;		\
1263 		i->private_attrs[count].store = NULL;			\
1264 	}								\
1265 	i->attrs[count] = &i->private_attrs[count];			\
1266 	if (i->f->show_##rel_field)					\
1267 		count++
1268 
1269 #define SETUP_HOST_ATTRIBUTE(field)					\
1270 	i->private_host_attrs[count] = class_device_attr_##field;	\
1271 	if (!i->f->set_##field) {					\
1272 		i->private_host_attrs[count].attr.mode = S_IRUGO;	\
1273 		i->private_host_attrs[count].store = NULL;		\
1274 	}								\
1275 	i->host_attrs[count] = &i->private_host_attrs[count];		\
1276 	count++
1277 
1278 static int spi_device_match(struct attribute_container *cont,
1279 			    struct device *dev)
1280 {
1281 	struct scsi_device *sdev;
1282 	struct Scsi_Host *shost;
1283 	struct spi_internal *i;
1284 
1285 	if (!scsi_is_sdev_device(dev))
1286 		return 0;
1287 
1288 	sdev = to_scsi_device(dev);
1289 	shost = sdev->host;
1290 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1291 	    != &spi_host_class.class)
1292 		return 0;
1293 	/* Note: this class has no device attributes, so it has
1294 	 * no per-HBA allocation and thus we don't need to distinguish
1295 	 * the attribute containers for the device */
1296 	i = to_spi_internal(shost->transportt);
1297 	if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1298 		return 0;
1299 	return 1;
1300 }
1301 
1302 static int spi_target_match(struct attribute_container *cont,
1303 			    struct device *dev)
1304 {
1305 	struct Scsi_Host *shost;
1306 	struct scsi_target *starget;
1307 	struct spi_internal *i;
1308 
1309 	if (!scsi_is_target_device(dev))
1310 		return 0;
1311 
1312 	shost = dev_to_shost(dev->parent);
1313 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1314 	    != &spi_host_class.class)
1315 		return 0;
1316 
1317 	i = to_spi_internal(shost->transportt);
1318 	starget = to_scsi_target(dev);
1319 
1320 	if (i->f->deny_binding && i->f->deny_binding(starget))
1321 		return 0;
1322 
1323 	return &i->t.target_attrs.ac == cont;
1324 }
1325 
1326 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1327 			       "spi_transport",
1328 			       spi_setup_transport_attrs,
1329 			       NULL,
1330 			       NULL);
1331 
1332 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1333 				    spi_device_match,
1334 				    spi_device_configure);
1335 
1336 struct scsi_transport_template *
1337 spi_attach_transport(struct spi_function_template *ft)
1338 {
1339 	int count = 0;
1340 	struct spi_internal *i = kzalloc(sizeof(struct spi_internal),
1341 					 GFP_KERNEL);
1342 
1343 	if (unlikely(!i))
1344 		return NULL;
1345 
1346 	i->t.target_attrs.ac.class = &spi_transport_class.class;
1347 	i->t.target_attrs.ac.attrs = &i->attrs[0];
1348 	i->t.target_attrs.ac.match = spi_target_match;
1349 	transport_container_register(&i->t.target_attrs);
1350 	i->t.target_size = sizeof(struct spi_transport_attrs);
1351 	i->t.host_attrs.ac.class = &spi_host_class.class;
1352 	i->t.host_attrs.ac.attrs = &i->host_attrs[0];
1353 	i->t.host_attrs.ac.match = spi_host_match;
1354 	transport_container_register(&i->t.host_attrs);
1355 	i->t.host_size = sizeof(struct spi_host_attrs);
1356 	i->f = ft;
1357 
1358 	SETUP_ATTRIBUTE(period);
1359 	SETUP_RELATED_ATTRIBUTE(min_period, period);
1360 	SETUP_ATTRIBUTE(offset);
1361 	SETUP_RELATED_ATTRIBUTE(max_offset, offset);
1362 	SETUP_ATTRIBUTE(width);
1363 	SETUP_RELATED_ATTRIBUTE(max_width, width);
1364 	SETUP_ATTRIBUTE(iu);
1365 	SETUP_ATTRIBUTE(dt);
1366 	SETUP_ATTRIBUTE(qas);
1367 	SETUP_ATTRIBUTE(wr_flow);
1368 	SETUP_ATTRIBUTE(rd_strm);
1369 	SETUP_ATTRIBUTE(rti);
1370 	SETUP_ATTRIBUTE(pcomp_en);
1371 	SETUP_ATTRIBUTE(hold_mcs);
1372 
1373 	/* if you add an attribute but forget to increase SPI_NUM_ATTRS
1374 	 * this bug will trigger */
1375 	BUG_ON(count > SPI_NUM_ATTRS);
1376 
1377 	i->attrs[count++] = &class_device_attr_revalidate;
1378 
1379 	i->attrs[count] = NULL;
1380 
1381 	count = 0;
1382 	SETUP_HOST_ATTRIBUTE(signalling);
1383 
1384 	BUG_ON(count > SPI_HOST_ATTRS);
1385 
1386 	i->host_attrs[count] = NULL;
1387 
1388 	return &i->t;
1389 }
1390 EXPORT_SYMBOL(spi_attach_transport);
1391 
1392 void spi_release_transport(struct scsi_transport_template *t)
1393 {
1394 	struct spi_internal *i = to_spi_internal(t);
1395 
1396 	transport_container_unregister(&i->t.target_attrs);
1397 	transport_container_unregister(&i->t.host_attrs);
1398 
1399 	kfree(i);
1400 }
1401 EXPORT_SYMBOL(spi_release_transport);
1402 
1403 static __init int spi_transport_init(void)
1404 {
1405 	int error = transport_class_register(&spi_transport_class);
1406 	if (error)
1407 		return error;
1408 	error = anon_transport_class_register(&spi_device_class);
1409 	return transport_class_register(&spi_host_class);
1410 }
1411 
1412 static void __exit spi_transport_exit(void)
1413 {
1414 	transport_class_unregister(&spi_transport_class);
1415 	anon_transport_class_unregister(&spi_device_class);
1416 	transport_class_unregister(&spi_host_class);
1417 }
1418 
1419 MODULE_AUTHOR("Martin Hicks");
1420 MODULE_DESCRIPTION("SPI Transport Attributes");
1421 MODULE_LICENSE("GPL");
1422 
1423 module_init(spi_transport_init);
1424 module_exit(spi_transport_exit);
1425