xref: /linux/drivers/scsi/scsi_transport_spi.c (revision c48a7c44a1d02516309015b6134c9bb982e17008)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
4  *
5  *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
6  *  Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
7  */
8 #include <linux/ctype.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/workqueue.h>
12 #include <linux/blkdev.h>
13 #include <linux/mutex.h>
14 #include <linux/sysfs.h>
15 #include <linux/slab.h>
16 #include <linux/suspend.h>
17 #include <scsi/scsi.h>
18 #include "scsi_priv.h"
19 #include <scsi/scsi_device.h>
20 #include <scsi/scsi_host.h>
21 #include <scsi/scsi_cmnd.h>
22 #include <scsi/scsi_eh.h>
23 #include <scsi/scsi_tcq.h>
24 #include <scsi/scsi_transport.h>
25 #include <scsi/scsi_transport_spi.h>
26 
27 #define SPI_NUM_ATTRS 14	/* increase this if you add attributes */
28 #define SPI_OTHER_ATTRS 1	/* Increase this if you add "always
29 				 * on" attributes */
30 #define SPI_HOST_ATTRS	1
31 
32 #define SPI_MAX_ECHO_BUFFER_SIZE	4096
33 
34 #define DV_LOOPS	3
35 #define DV_TIMEOUT	(10*HZ)
36 #define DV_RETRIES	3	/* should only need at most
37 				 * two cc/ua clears */
38 
39 /* Our blacklist flags */
40 enum {
41 	SPI_BLIST_NOIUS = (__force blist_flags_t)0x1,
42 };
43 
44 /* blacklist table, modelled on scsi_devinfo.c */
45 static struct {
46 	char *vendor;
47 	char *model;
48 	blist_flags_t flags;
49 } spi_static_device_list[] __initdata = {
50 	{"HP", "Ultrium 3-SCSI", SPI_BLIST_NOIUS },
51 	{"IBM", "ULTRIUM-TD3", SPI_BLIST_NOIUS },
52 	{NULL, NULL, 0}
53 };
54 
55 /* Private data accessors (keep these out of the header file) */
56 #define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
57 #define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
58 
59 struct spi_internal {
60 	struct scsi_transport_template t;
61 	struct spi_function_template *f;
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 req_op op, void *buffer, unsigned int bufflen,
109 		       struct scsi_sense_hdr *sshdr)
110 {
111 	int i, result;
112 	struct scsi_sense_hdr sshdr_tmp;
113 	blk_opf_t opf = op | REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
114 			REQ_FAILFAST_DRIVER;
115 	const struct scsi_exec_args exec_args = {
116 		.req_flags = BLK_MQ_REQ_PM,
117 		.sshdr = sshdr ? : &sshdr_tmp,
118 	};
119 
120 	sshdr = exec_args.sshdr;
121 
122 	for(i = 0; i < DV_RETRIES; i++) {
123 		/*
124 		 * The purpose of the RQF_PM flag below is to bypass the
125 		 * SDEV_QUIESCE state.
126 		 */
127 		result = scsi_execute_cmd(sdev, cmd, opf, buffer, bufflen,
128 					  DV_TIMEOUT, 1, &exec_args);
129 		if (result < 0 || !scsi_sense_valid(sshdr) ||
130 		    sshdr->sense_key != UNIT_ATTENTION)
131 			break;
132 	}
133 	return result;
134 }
135 
136 static struct {
137 	enum spi_signal_type	value;
138 	char			*name;
139 } signal_types[] = {
140 	{ SPI_SIGNAL_UNKNOWN, "unknown" },
141 	{ SPI_SIGNAL_SE, "SE" },
142 	{ SPI_SIGNAL_LVD, "LVD" },
143 	{ SPI_SIGNAL_HVD, "HVD" },
144 };
145 
146 static inline const char *spi_signal_to_string(enum spi_signal_type type)
147 {
148 	int i;
149 
150 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
151 		if (type == signal_types[i].value)
152 			return signal_types[i].name;
153 	}
154 	return NULL;
155 }
156 static inline enum spi_signal_type spi_signal_to_value(const char *name)
157 {
158 	int i, len;
159 
160 	for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
161 		len =  strlen(signal_types[i].name);
162 		if (strncmp(name, signal_types[i].name, len) == 0 &&
163 		    (name[len] == '\n' || name[len] == '\0'))
164 			return signal_types[i].value;
165 	}
166 	return SPI_SIGNAL_UNKNOWN;
167 }
168 
169 static int spi_host_setup(struct transport_container *tc, struct device *dev,
170 			  struct device *cdev)
171 {
172 	struct Scsi_Host *shost = dev_to_shost(dev);
173 
174 	spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
175 
176 	return 0;
177 }
178 
179 static int spi_host_configure(struct transport_container *tc,
180 			      struct device *dev,
181 			      struct device *cdev);
182 
183 static DECLARE_TRANSPORT_CLASS(spi_host_class,
184 			       "spi_host",
185 			       spi_host_setup,
186 			       NULL,
187 			       spi_host_configure);
188 
189 static int spi_host_match(struct attribute_container *cont,
190 			  struct device *dev)
191 {
192 	struct Scsi_Host *shost;
193 
194 	if (!scsi_is_host_device(dev))
195 		return 0;
196 
197 	shost = dev_to_shost(dev);
198 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
199 	    != &spi_host_class.class)
200 		return 0;
201 
202 	return &shost->transportt->host_attrs.ac == cont;
203 }
204 
205 static int spi_target_configure(struct transport_container *tc,
206 				struct device *dev,
207 				struct device *cdev);
208 
209 static int spi_device_configure(struct transport_container *tc,
210 				struct device *dev,
211 				struct device *cdev)
212 {
213 	struct scsi_device *sdev = to_scsi_device(dev);
214 	struct scsi_target *starget = sdev->sdev_target;
215 	blist_flags_t bflags;
216 
217 	bflags = scsi_get_device_flags_keyed(sdev, &sdev->inquiry[8],
218 					     &sdev->inquiry[16],
219 					     SCSI_DEVINFO_SPI);
220 
221 	/* Populate the target capability fields with the values
222 	 * gleaned from the device inquiry */
223 
224 	spi_support_sync(starget) = scsi_device_sync(sdev);
225 	spi_support_wide(starget) = scsi_device_wide(sdev);
226 	spi_support_dt(starget) = scsi_device_dt(sdev);
227 	spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
228 	spi_support_ius(starget) = scsi_device_ius(sdev);
229 	if (bflags & SPI_BLIST_NOIUS) {
230 		dev_info(dev, "Information Units disabled by blacklist\n");
231 		spi_support_ius(starget) = 0;
232 	}
233 	spi_support_qas(starget) = scsi_device_qas(sdev);
234 
235 	return 0;
236 }
237 
238 static int spi_setup_transport_attrs(struct transport_container *tc,
239 				     struct device *dev,
240 				     struct device *cdev)
241 {
242 	struct scsi_target *starget = to_scsi_target(dev);
243 
244 	spi_period(starget) = -1;	/* illegal value */
245 	spi_min_period(starget) = 0;
246 	spi_offset(starget) = 0;	/* async */
247 	spi_max_offset(starget) = 255;
248 	spi_width(starget) = 0;	/* narrow */
249 	spi_max_width(starget) = 1;
250 	spi_iu(starget) = 0;	/* no IU */
251 	spi_max_iu(starget) = 1;
252 	spi_dt(starget) = 0;	/* ST */
253 	spi_qas(starget) = 0;
254 	spi_max_qas(starget) = 1;
255 	spi_wr_flow(starget) = 0;
256 	spi_rd_strm(starget) = 0;
257 	spi_rti(starget) = 0;
258 	spi_pcomp_en(starget) = 0;
259 	spi_hold_mcs(starget) = 0;
260 	spi_dv_pending(starget) = 0;
261 	spi_dv_in_progress(starget) = 0;
262 	spi_initial_dv(starget) = 0;
263 	mutex_init(&spi_dv_mutex(starget));
264 
265 	return 0;
266 }
267 
268 #define spi_transport_show_simple(field, format_string)			\
269 									\
270 static ssize_t								\
271 show_spi_transport_##field(struct device *dev, 			\
272 			   struct device_attribute *attr, char *buf)	\
273 {									\
274 	struct scsi_target *starget = transport_class_to_starget(dev);	\
275 	struct spi_transport_attrs *tp;					\
276 									\
277 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
278 	return snprintf(buf, 20, format_string, tp->field);		\
279 }
280 
281 #define spi_transport_store_simple(field, format_string)		\
282 									\
283 static ssize_t								\
284 store_spi_transport_##field(struct device *dev, 			\
285 			    struct device_attribute *attr, 		\
286 			    const char *buf, size_t count)		\
287 {									\
288 	int val;							\
289 	struct scsi_target *starget = transport_class_to_starget(dev);	\
290 	struct spi_transport_attrs *tp;					\
291 									\
292 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
293 	val = simple_strtoul(buf, NULL, 0);				\
294 	tp->field = val;						\
295 	return count;							\
296 }
297 
298 #define spi_transport_show_function(field, format_string)		\
299 									\
300 static ssize_t								\
301 show_spi_transport_##field(struct device *dev, 			\
302 			   struct device_attribute *attr, char *buf)	\
303 {									\
304 	struct scsi_target *starget = transport_class_to_starget(dev);	\
305 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
306 	struct spi_transport_attrs *tp;					\
307 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
308 	tp = (struct spi_transport_attrs *)&starget->starget_data;	\
309 	if (i->f->get_##field)						\
310 		i->f->get_##field(starget);				\
311 	return snprintf(buf, 20, format_string, tp->field);		\
312 }
313 
314 #define spi_transport_store_function(field, format_string)		\
315 static ssize_t								\
316 store_spi_transport_##field(struct device *dev, 			\
317 			    struct device_attribute *attr,		\
318 			    const char *buf, size_t count)		\
319 {									\
320 	int val;							\
321 	struct scsi_target *starget = transport_class_to_starget(dev);	\
322 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
323 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
324 									\
325 	if (!i->f->set_##field)						\
326 		return -EINVAL;						\
327 	val = simple_strtoul(buf, NULL, 0);				\
328 	i->f->set_##field(starget, val);				\
329 	return count;							\
330 }
331 
332 #define spi_transport_store_max(field, format_string)			\
333 static ssize_t								\
334 store_spi_transport_##field(struct device *dev, 			\
335 			    struct device_attribute *attr,		\
336 			    const char *buf, size_t count)		\
337 {									\
338 	int val;							\
339 	struct scsi_target *starget = transport_class_to_starget(dev);	\
340 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);	\
341 	struct spi_internal *i = to_spi_internal(shost->transportt);	\
342 	struct spi_transport_attrs *tp					\
343 		= (struct spi_transport_attrs *)&starget->starget_data;	\
344 									\
345 	if (!i->f->set_##field)						\
346 		return -EINVAL;						\
347 	val = simple_strtoul(buf, NULL, 0);				\
348 	if (val > tp->max_##field)					\
349 		val = tp->max_##field;					\
350 	i->f->set_##field(starget, val);				\
351 	return count;							\
352 }
353 
354 #define spi_transport_rd_attr(field, format_string)			\
355 	spi_transport_show_function(field, format_string)		\
356 	spi_transport_store_function(field, format_string)		\
357 static DEVICE_ATTR(field, S_IRUGO,				\
358 		   show_spi_transport_##field,			\
359 		   store_spi_transport_##field);
360 
361 #define spi_transport_simple_attr(field, format_string)			\
362 	spi_transport_show_simple(field, format_string)			\
363 	spi_transport_store_simple(field, format_string)		\
364 static DEVICE_ATTR(field, S_IRUGO,				\
365 		   show_spi_transport_##field,			\
366 		   store_spi_transport_##field);
367 
368 #define spi_transport_max_attr(field, format_string)			\
369 	spi_transport_show_function(field, format_string)		\
370 	spi_transport_store_max(field, format_string)			\
371 	spi_transport_simple_attr(max_##field, format_string)		\
372 static DEVICE_ATTR(field, S_IRUGO,				\
373 		   show_spi_transport_##field,			\
374 		   store_spi_transport_##field);
375 
376 /* The Parallel SCSI Tranport Attributes: */
377 spi_transport_max_attr(offset, "%d\n");
378 spi_transport_max_attr(width, "%d\n");
379 spi_transport_max_attr(iu, "%d\n");
380 spi_transport_rd_attr(dt, "%d\n");
381 spi_transport_max_attr(qas, "%d\n");
382 spi_transport_rd_attr(wr_flow, "%d\n");
383 spi_transport_rd_attr(rd_strm, "%d\n");
384 spi_transport_rd_attr(rti, "%d\n");
385 spi_transport_rd_attr(pcomp_en, "%d\n");
386 spi_transport_rd_attr(hold_mcs, "%d\n");
387 
388 /* we only care about the first child device that's a real SCSI device
389  * so we return 1 to terminate the iteration when we find it */
390 static int child_iter(struct device *dev, void *data)
391 {
392 	if (!scsi_is_sdev_device(dev))
393 		return 0;
394 
395 	spi_dv_device(to_scsi_device(dev));
396 	return 1;
397 }
398 
399 static ssize_t
400 store_spi_revalidate(struct device *dev, struct device_attribute *attr,
401 		     const char *buf, size_t count)
402 {
403 	struct scsi_target *starget = transport_class_to_starget(dev);
404 
405 	device_for_each_child(&starget->dev, NULL, child_iter);
406 	return count;
407 }
408 static DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
409 
410 /* Translate the period into ns according to the current spec
411  * for SDTR/PPR messages */
412 static int period_to_str(char *buf, int period)
413 {
414 	int len, picosec;
415 
416 	if (period < 0 || period > 0xff) {
417 		picosec = -1;
418 	} else if (period <= SPI_STATIC_PPR) {
419 		picosec = ppr_to_ps[period];
420 	} else {
421 		picosec = period * 4000;
422 	}
423 
424 	if (picosec == -1) {
425 		len = sprintf(buf, "reserved");
426 	} else {
427 		len = sprint_frac(buf, picosec, 1000);
428 	}
429 
430 	return len;
431 }
432 
433 static ssize_t
434 show_spi_transport_period_helper(char *buf, int period)
435 {
436 	int len = period_to_str(buf, period);
437 	buf[len++] = '\n';
438 	buf[len] = '\0';
439 	return len;
440 }
441 
442 static ssize_t
443 store_spi_transport_period_helper(struct device *dev, const char *buf,
444 				  size_t count, int *periodp)
445 {
446 	int j, picosec, period = -1;
447 	char *endp;
448 
449 	picosec = simple_strtoul(buf, &endp, 10) * 1000;
450 	if (*endp == '.') {
451 		int mult = 100;
452 		do {
453 			endp++;
454 			if (!isdigit(*endp))
455 				break;
456 			picosec += (*endp - '0') * mult;
457 			mult /= 10;
458 		} while (mult > 0);
459 	}
460 
461 	for (j = 0; j <= SPI_STATIC_PPR; j++) {
462 		if (ppr_to_ps[j] < picosec)
463 			continue;
464 		period = j;
465 		break;
466 	}
467 
468 	if (period == -1)
469 		period = picosec / 4000;
470 
471 	if (period > 0xff)
472 		period = 0xff;
473 
474 	*periodp = period;
475 
476 	return count;
477 }
478 
479 static ssize_t
480 show_spi_transport_period(struct device *dev,
481 			  struct device_attribute *attr, char *buf)
482 {
483 	struct scsi_target *starget = transport_class_to_starget(dev);
484 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
485 	struct spi_internal *i = to_spi_internal(shost->transportt);
486 	struct spi_transport_attrs *tp =
487 		(struct spi_transport_attrs *)&starget->starget_data;
488 
489 	if (i->f->get_period)
490 		i->f->get_period(starget);
491 
492 	return show_spi_transport_period_helper(buf, tp->period);
493 }
494 
495 static ssize_t
496 store_spi_transport_period(struct device *cdev, struct device_attribute *attr,
497 			   const char *buf, size_t count)
498 {
499 	struct scsi_target *starget = transport_class_to_starget(cdev);
500 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
501 	struct spi_internal *i = to_spi_internal(shost->transportt);
502 	struct spi_transport_attrs *tp =
503 		(struct spi_transport_attrs *)&starget->starget_data;
504 	int period, retval;
505 
506 	if (!i->f->set_period)
507 		return -EINVAL;
508 
509 	retval = store_spi_transport_period_helper(cdev, buf, count, &period);
510 
511 	if (period < tp->min_period)
512 		period = tp->min_period;
513 
514 	i->f->set_period(starget, period);
515 
516 	return retval;
517 }
518 
519 static DEVICE_ATTR(period, S_IRUGO,
520 		   show_spi_transport_period,
521 		   store_spi_transport_period);
522 
523 static ssize_t
524 show_spi_transport_min_period(struct device *cdev,
525 			      struct device_attribute *attr, char *buf)
526 {
527 	struct scsi_target *starget = transport_class_to_starget(cdev);
528 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
529 	struct spi_internal *i = to_spi_internal(shost->transportt);
530 	struct spi_transport_attrs *tp =
531 		(struct spi_transport_attrs *)&starget->starget_data;
532 
533 	if (!i->f->set_period)
534 		return -EINVAL;
535 
536 	return show_spi_transport_period_helper(buf, tp->min_period);
537 }
538 
539 static ssize_t
540 store_spi_transport_min_period(struct device *cdev,
541 			       struct device_attribute *attr,
542 			       const char *buf, size_t count)
543 {
544 	struct scsi_target *starget = transport_class_to_starget(cdev);
545 	struct spi_transport_attrs *tp =
546 		(struct spi_transport_attrs *)&starget->starget_data;
547 
548 	return store_spi_transport_period_helper(cdev, buf, count,
549 						 &tp->min_period);
550 }
551 
552 
553 static DEVICE_ATTR(min_period, S_IRUGO,
554 		   show_spi_transport_min_period,
555 		   store_spi_transport_min_period);
556 
557 
558 static ssize_t show_spi_host_signalling(struct device *cdev,
559 					struct device_attribute *attr,
560 					char *buf)
561 {
562 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
563 	struct spi_internal *i = to_spi_internal(shost->transportt);
564 
565 	if (i->f->get_signalling)
566 		i->f->get_signalling(shost);
567 
568 	return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
569 }
570 static ssize_t store_spi_host_signalling(struct device *dev,
571 					 struct device_attribute *attr,
572 					 const char *buf, size_t count)
573 {
574 	struct Scsi_Host *shost = transport_class_to_shost(dev);
575 	struct spi_internal *i = to_spi_internal(shost->transportt);
576 	enum spi_signal_type type = spi_signal_to_value(buf);
577 
578 	if (!i->f->set_signalling)
579 		return -EINVAL;
580 
581 	if (type != SPI_SIGNAL_UNKNOWN)
582 		i->f->set_signalling(shost, type);
583 
584 	return count;
585 }
586 static DEVICE_ATTR(signalling, S_IRUGO,
587 		   show_spi_host_signalling,
588 		   store_spi_host_signalling);
589 
590 static ssize_t show_spi_host_width(struct device *cdev,
591 				      struct device_attribute *attr,
592 				      char *buf)
593 {
594 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
595 
596 	return sprintf(buf, "%s\n", shost->max_id == 16 ? "wide" : "narrow");
597 }
598 static DEVICE_ATTR(host_width, S_IRUGO,
599 		   show_spi_host_width, NULL);
600 
601 static ssize_t show_spi_host_hba_id(struct device *cdev,
602 				    struct device_attribute *attr,
603 				    char *buf)
604 {
605 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
606 
607 	return sprintf(buf, "%d\n", shost->this_id);
608 }
609 static DEVICE_ATTR(hba_id, S_IRUGO,
610 		   show_spi_host_hba_id, NULL);
611 
612 #define DV_SET(x, y)			\
613 	if(i->f->set_##x)		\
614 		i->f->set_##x(sdev->sdev_target, y)
615 
616 enum spi_compare_returns {
617 	SPI_COMPARE_SUCCESS,
618 	SPI_COMPARE_FAILURE,
619 	SPI_COMPARE_SKIP_TEST,
620 };
621 
622 
623 /* This is for read/write Domain Validation:  If the device supports
624  * an echo buffer, we do read/write tests to it */
625 static enum spi_compare_returns
626 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
627 			  u8 *ptr, const int retries)
628 {
629 	int len = ptr - buffer;
630 	int j, k, r, result;
631 	unsigned int pattern = 0x0000ffff;
632 	struct scsi_sense_hdr sshdr;
633 
634 	const char spi_write_buffer[] = {
635 		WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
636 	};
637 	const char spi_read_buffer[] = {
638 		READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
639 	};
640 
641 	/* set up the pattern buffer.  Doesn't matter if we spill
642 	 * slightly beyond since that's where the read buffer is */
643 	for (j = 0; j < len; ) {
644 
645 		/* fill the buffer with counting (test a) */
646 		for ( ; j < min(len, 32); j++)
647 			buffer[j] = j;
648 		k = j;
649 		/* fill the buffer with alternating words of 0x0 and
650 		 * 0xffff (test b) */
651 		for ( ; j < min(len, k + 32); j += 2) {
652 			u16 *word = (u16 *)&buffer[j];
653 
654 			*word = (j & 0x02) ? 0x0000 : 0xffff;
655 		}
656 		k = j;
657 		/* fill with crosstalk (alternating 0x5555 0xaaa)
658                  * (test c) */
659 		for ( ; j < min(len, k + 32); j += 2) {
660 			u16 *word = (u16 *)&buffer[j];
661 
662 			*word = (j & 0x02) ? 0x5555 : 0xaaaa;
663 		}
664 		k = j;
665 		/* fill with shifting bits (test d) */
666 		for ( ; j < min(len, k + 32); j += 4) {
667 			u32 *word = (unsigned int *)&buffer[j];
668 			u32 roll = (pattern & 0x80000000) ? 1 : 0;
669 
670 			*word = pattern;
671 			pattern = (pattern << 1) | roll;
672 		}
673 		/* don't bother with random data (test e) */
674 	}
675 
676 	for (r = 0; r < retries; r++) {
677 		result = spi_execute(sdev, spi_write_buffer, REQ_OP_DRV_OUT,
678 				     buffer, len, &sshdr);
679 		if (result || !scsi_device_online(sdev)) {
680 
681 			scsi_device_set_state(sdev, SDEV_QUIESCE);
682 			if (result > 0 && scsi_sense_valid(&sshdr)
683 			    && sshdr.sense_key == ILLEGAL_REQUEST
684 			    /* INVALID FIELD IN CDB */
685 			    && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
686 				/* This would mean that the drive lied
687 				 * to us about supporting an echo
688 				 * buffer (unfortunately some Western
689 				 * Digital drives do precisely this)
690 				 */
691 				return SPI_COMPARE_SKIP_TEST;
692 
693 
694 			sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
695 			return SPI_COMPARE_FAILURE;
696 		}
697 
698 		memset(ptr, 0, len);
699 		spi_execute(sdev, spi_read_buffer, REQ_OP_DRV_IN,
700 			    ptr, len, NULL);
701 		scsi_device_set_state(sdev, SDEV_QUIESCE);
702 
703 		if (memcmp(buffer, ptr, len) != 0)
704 			return SPI_COMPARE_FAILURE;
705 	}
706 	return SPI_COMPARE_SUCCESS;
707 }
708 
709 /* This is for the simplest form of Domain Validation: a read test
710  * on the inquiry data from the device */
711 static enum spi_compare_returns
712 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
713 			      u8 *ptr, const int retries)
714 {
715 	int r, result;
716 	const int len = sdev->inquiry_len;
717 	const char spi_inquiry[] = {
718 		INQUIRY, 0, 0, 0, len, 0
719 	};
720 
721 	for (r = 0; r < retries; r++) {
722 		memset(ptr, 0, len);
723 
724 		result = spi_execute(sdev, spi_inquiry, REQ_OP_DRV_IN,
725 				     ptr, len, NULL);
726 
727 		if(result || !scsi_device_online(sdev)) {
728 			scsi_device_set_state(sdev, SDEV_QUIESCE);
729 			return SPI_COMPARE_FAILURE;
730 		}
731 
732 		/* If we don't have the inquiry data already, the
733 		 * first read gets it */
734 		if (ptr == buffer) {
735 			ptr += len;
736 			--r;
737 			continue;
738 		}
739 
740 		if (memcmp(buffer, ptr, len) != 0)
741 			/* failure */
742 			return SPI_COMPARE_FAILURE;
743 	}
744 	return SPI_COMPARE_SUCCESS;
745 }
746 
747 static enum spi_compare_returns
748 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
749 	       enum spi_compare_returns
750 	       (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
751 {
752 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
753 	struct scsi_target *starget = sdev->sdev_target;
754 	int period = 0, prevperiod = 0;
755 	enum spi_compare_returns retval;
756 
757 
758 	for (;;) {
759 		int newperiod;
760 		retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
761 
762 		if (retval == SPI_COMPARE_SUCCESS
763 		    || retval == SPI_COMPARE_SKIP_TEST)
764 			break;
765 
766 		/* OK, retrain, fallback */
767 		if (i->f->get_iu)
768 			i->f->get_iu(starget);
769 		if (i->f->get_qas)
770 			i->f->get_qas(starget);
771 		if (i->f->get_period)
772 			i->f->get_period(sdev->sdev_target);
773 
774 		/* Here's the fallback sequence; first try turning off
775 		 * IU, then QAS (if we can control them), then finally
776 		 * fall down the periods */
777 		if (i->f->set_iu && spi_iu(starget)) {
778 			starget_printk(KERN_ERR, starget, "Domain Validation Disabling Information Units\n");
779 			DV_SET(iu, 0);
780 		} else if (i->f->set_qas && spi_qas(starget)) {
781 			starget_printk(KERN_ERR, starget, "Domain Validation Disabling Quick Arbitration and Selection\n");
782 			DV_SET(qas, 0);
783 		} else {
784 			newperiod = spi_period(starget);
785 			period = newperiod > period ? newperiod : period;
786 			if (period < 0x0d)
787 				period++;
788 			else
789 				period += period >> 1;
790 
791 			if (unlikely(period > 0xff || period == prevperiod)) {
792 				/* Total failure; set to async and return */
793 				starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
794 				DV_SET(offset, 0);
795 				return SPI_COMPARE_FAILURE;
796 			}
797 			starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
798 			DV_SET(period, period);
799 			prevperiod = period;
800 		}
801 	}
802 	return retval;
803 }
804 
805 static int
806 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
807 {
808 	int l, result;
809 
810 	/* first off do a test unit ready.  This can error out
811 	 * because of reservations or some other reason.  If it
812 	 * fails, the device won't let us write to the echo buffer
813 	 * so just return failure */
814 
815 	static const char spi_test_unit_ready[] = {
816 		TEST_UNIT_READY, 0, 0, 0, 0, 0
817 	};
818 
819 	static const char spi_read_buffer_descriptor[] = {
820 		READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
821 	};
822 
823 
824 	/* We send a set of three TURs to clear any outstanding
825 	 * unit attention conditions if they exist (Otherwise the
826 	 * buffer tests won't be happy).  If the TUR still fails
827 	 * (reservation conflict, device not ready, etc) just
828 	 * skip the write tests */
829 	for (l = 0; ; l++) {
830 		result = spi_execute(sdev, spi_test_unit_ready, REQ_OP_DRV_IN,
831 				     NULL, 0, NULL);
832 
833 		if(result) {
834 			if(l >= 3)
835 				return 0;
836 		} else {
837 			/* TUR succeeded */
838 			break;
839 		}
840 	}
841 
842 	result = spi_execute(sdev, spi_read_buffer_descriptor,
843 			     REQ_OP_DRV_IN, buffer, 4, NULL);
844 
845 	if (result)
846 		/* Device has no echo buffer */
847 		return 0;
848 
849 	return buffer[3] + ((buffer[2] & 0x1f) << 8);
850 }
851 
852 static void
853 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
854 {
855 	struct spi_internal *i = to_spi_internal(sdev->host->transportt);
856 	struct scsi_target *starget = sdev->sdev_target;
857 	struct Scsi_Host *shost = sdev->host;
858 	int len = sdev->inquiry_len;
859 	int min_period = spi_min_period(starget);
860 	int max_width = spi_max_width(starget);
861 	/* first set us up for narrow async */
862 	DV_SET(offset, 0);
863 	DV_SET(width, 0);
864 
865 	if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
866 	    != SPI_COMPARE_SUCCESS) {
867 		starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
868 		/* FIXME: should probably offline the device here? */
869 		return;
870 	}
871 
872 	if (!spi_support_wide(starget)) {
873 		spi_max_width(starget) = 0;
874 		max_width = 0;
875 	}
876 
877 	/* test width */
878 	if (i->f->set_width && max_width) {
879 		i->f->set_width(starget, 1);
880 
881 		if (spi_dv_device_compare_inquiry(sdev, buffer,
882 						   buffer + len,
883 						   DV_LOOPS)
884 		    != SPI_COMPARE_SUCCESS) {
885 			starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
886 			i->f->set_width(starget, 0);
887 			/* Make sure we don't force wide back on by asking
888 			 * for a transfer period that requires it */
889 			max_width = 0;
890 			if (min_period < 10)
891 				min_period = 10;
892 		}
893 	}
894 
895 	if (!i->f->set_period)
896 		return;
897 
898 	/* device can't handle synchronous */
899 	if (!spi_support_sync(starget) && !spi_support_dt(starget))
900 		return;
901 
902 	/* len == -1 is the signal that we need to ascertain the
903 	 * presence of an echo buffer before trying to use it.  len ==
904 	 * 0 means we don't have an echo buffer */
905 	len = -1;
906 
907  retry:
908 
909 	/* now set up to the maximum */
910 	DV_SET(offset, spi_max_offset(starget));
911 	DV_SET(period, min_period);
912 
913 	/* try QAS requests; this should be harmless to set if the
914 	 * target supports it */
915 	if (spi_support_qas(starget) && spi_max_qas(starget)) {
916 		DV_SET(qas, 1);
917 	} else {
918 		DV_SET(qas, 0);
919 	}
920 
921 	if (spi_support_ius(starget) && spi_max_iu(starget) &&
922 	    min_period < 9) {
923 		/* This u320 (or u640). Set IU transfers */
924 		DV_SET(iu, 1);
925 		/* Then set the optional parameters */
926 		DV_SET(rd_strm, 1);
927 		DV_SET(wr_flow, 1);
928 		DV_SET(rti, 1);
929 		if (min_period == 8)
930 			DV_SET(pcomp_en, 1);
931 	} else {
932 		DV_SET(iu, 0);
933 	}
934 
935 	/* now that we've done all this, actually check the bus
936 	 * signal type (if known).  Some devices are stupid on
937 	 * a SE bus and still claim they can try LVD only settings */
938 	if (i->f->get_signalling)
939 		i->f->get_signalling(shost);
940 	if (spi_signalling(shost) == SPI_SIGNAL_SE ||
941 	    spi_signalling(shost) == SPI_SIGNAL_HVD ||
942 	    !spi_support_dt(starget)) {
943 		DV_SET(dt, 0);
944 	} else {
945 		DV_SET(dt, 1);
946 	}
947 	/* set width last because it will pull all the other
948 	 * parameters down to required values */
949 	DV_SET(width, max_width);
950 
951 	/* Do the read only INQUIRY tests */
952 	spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
953 		       spi_dv_device_compare_inquiry);
954 	/* See if we actually managed to negotiate and sustain DT */
955 	if (i->f->get_dt)
956 		i->f->get_dt(starget);
957 
958 	/* see if the device has an echo buffer.  If it does we can do
959 	 * the SPI pattern write tests.  Because of some broken
960 	 * devices, we *only* try this on a device that has actually
961 	 * negotiated DT */
962 
963 	if (len == -1 && spi_dt(starget))
964 		len = spi_dv_device_get_echo_buffer(sdev, buffer);
965 
966 	if (len <= 0) {
967 		starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
968 		return;
969 	}
970 
971 	if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
972 		starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
973 		len = SPI_MAX_ECHO_BUFFER_SIZE;
974 	}
975 
976 	if (spi_dv_retrain(sdev, buffer, buffer + len,
977 			   spi_dv_device_echo_buffer)
978 	    == SPI_COMPARE_SKIP_TEST) {
979 		/* OK, the stupid drive can't do a write echo buffer
980 		 * test after all, fall back to the read tests */
981 		len = 0;
982 		goto retry;
983 	}
984 }
985 
986 
987 /**	spi_dv_device - Do Domain Validation on the device
988  *	@sdev:		scsi device to validate
989  *
990  *	Performs the domain validation on the given device in the
991  *	current execution thread.  Since DV operations may sleep,
992  *	the current thread must have user context.  Also no SCSI
993  *	related locks that would deadlock I/O issued by the DV may
994  *	be held.
995  */
996 void
997 spi_dv_device(struct scsi_device *sdev)
998 {
999 	struct scsi_target *starget = sdev->sdev_target;
1000 	const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
1001 	unsigned int sleep_flags;
1002 	u8 *buffer;
1003 
1004 	/*
1005 	 * Because this function and the power management code both call
1006 	 * scsi_device_quiesce(), it is not safe to perform domain validation
1007 	 * while suspend or resume is in progress. Hence the
1008 	 * lock/unlock_system_sleep() calls.
1009 	 */
1010 	sleep_flags = lock_system_sleep();
1011 
1012 	if (scsi_autopm_get_device(sdev))
1013 		goto unlock_system_sleep;
1014 
1015 	if (unlikely(spi_dv_in_progress(starget)))
1016 		goto put_autopm;
1017 
1018 	if (unlikely(scsi_device_get(sdev)))
1019 		goto put_autopm;
1020 
1021 	spi_dv_in_progress(starget) = 1;
1022 
1023 	buffer = kzalloc(len, GFP_KERNEL);
1024 
1025 	if (unlikely(!buffer))
1026 		goto put_sdev;
1027 
1028 	/* We need to verify that the actual device will quiesce; the
1029 	 * later target quiesce is just a nice to have */
1030 	if (unlikely(scsi_device_quiesce(sdev)))
1031 		goto free_buffer;
1032 
1033 	scsi_target_quiesce(starget);
1034 
1035 	spi_dv_pending(starget) = 1;
1036 	mutex_lock(&spi_dv_mutex(starget));
1037 
1038 	starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
1039 
1040 	spi_dv_device_internal(sdev, buffer);
1041 
1042 	starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
1043 
1044 	mutex_unlock(&spi_dv_mutex(starget));
1045 	spi_dv_pending(starget) = 0;
1046 
1047 	scsi_target_resume(starget);
1048 
1049 	spi_initial_dv(starget) = 1;
1050 
1051 free_buffer:
1052 	kfree(buffer);
1053 
1054 put_sdev:
1055 	spi_dv_in_progress(starget) = 0;
1056 	scsi_device_put(sdev);
1057 put_autopm:
1058 	scsi_autopm_put_device(sdev);
1059 
1060 unlock_system_sleep:
1061 	unlock_system_sleep(sleep_flags);
1062 }
1063 EXPORT_SYMBOL(spi_dv_device);
1064 
1065 struct work_queue_wrapper {
1066 	struct work_struct	work;
1067 	struct scsi_device	*sdev;
1068 };
1069 
1070 static void
1071 spi_dv_device_work_wrapper(struct work_struct *work)
1072 {
1073 	struct work_queue_wrapper *wqw =
1074 		container_of(work, struct work_queue_wrapper, work);
1075 	struct scsi_device *sdev = wqw->sdev;
1076 
1077 	kfree(wqw);
1078 	spi_dv_device(sdev);
1079 	spi_dv_pending(sdev->sdev_target) = 0;
1080 	scsi_device_put(sdev);
1081 }
1082 
1083 
1084 /**
1085  *	spi_schedule_dv_device - schedule domain validation to occur on the device
1086  *	@sdev:	The device to validate
1087  *
1088  *	Identical to spi_dv_device() above, except that the DV will be
1089  *	scheduled to occur in a workqueue later.  All memory allocations
1090  *	are atomic, so may be called from any context including those holding
1091  *	SCSI locks.
1092  */
1093 void
1094 spi_schedule_dv_device(struct scsi_device *sdev)
1095 {
1096 	struct work_queue_wrapper *wqw =
1097 		kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
1098 
1099 	if (unlikely(!wqw))
1100 		return;
1101 
1102 	if (unlikely(spi_dv_pending(sdev->sdev_target))) {
1103 		kfree(wqw);
1104 		return;
1105 	}
1106 	/* Set pending early (dv_device doesn't check it, only sets it) */
1107 	spi_dv_pending(sdev->sdev_target) = 1;
1108 	if (unlikely(scsi_device_get(sdev))) {
1109 		kfree(wqw);
1110 		spi_dv_pending(sdev->sdev_target) = 0;
1111 		return;
1112 	}
1113 
1114 	INIT_WORK(&wqw->work, spi_dv_device_work_wrapper);
1115 	wqw->sdev = sdev;
1116 
1117 	schedule_work(&wqw->work);
1118 }
1119 EXPORT_SYMBOL(spi_schedule_dv_device);
1120 
1121 /**
1122  * spi_display_xfer_agreement - Print the current target transfer agreement
1123  * @starget: The target for which to display the agreement
1124  *
1125  * Each SPI port is required to maintain a transfer agreement for each
1126  * other port on the bus.  This function prints a one-line summary of
1127  * the current agreement; more detailed information is available in sysfs.
1128  */
1129 void spi_display_xfer_agreement(struct scsi_target *starget)
1130 {
1131 	struct spi_transport_attrs *tp;
1132 	tp = (struct spi_transport_attrs *)&starget->starget_data;
1133 
1134 	if (tp->offset > 0 && tp->period > 0) {
1135 		unsigned int picosec, kb100;
1136 		char *scsi = "FAST-?";
1137 		char tmp[8];
1138 
1139 		if (tp->period <= SPI_STATIC_PPR) {
1140 			picosec = ppr_to_ps[tp->period];
1141 			switch (tp->period) {
1142 				case  7: scsi = "FAST-320"; break;
1143 				case  8: scsi = "FAST-160"; break;
1144 				case  9: scsi = "FAST-80"; break;
1145 				case 10:
1146 				case 11: scsi = "FAST-40"; break;
1147 				case 12: scsi = "FAST-20"; break;
1148 			}
1149 		} else {
1150 			picosec = tp->period * 4000;
1151 			if (tp->period < 25)
1152 				scsi = "FAST-20";
1153 			else if (tp->period < 50)
1154 				scsi = "FAST-10";
1155 			else
1156 				scsi = "FAST-5";
1157 		}
1158 
1159 		kb100 = (10000000 + picosec / 2) / picosec;
1160 		if (tp->width)
1161 			kb100 *= 2;
1162 		sprint_frac(tmp, picosec, 1000);
1163 
1164 		dev_info(&starget->dev,
1165 			 "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1166 			 scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1167 			 tp->dt ? "DT" : "ST",
1168 			 tp->iu ? " IU" : "",
1169 			 tp->qas  ? " QAS" : "",
1170 			 tp->rd_strm ? " RDSTRM" : "",
1171 			 tp->rti ? " RTI" : "",
1172 			 tp->wr_flow ? " WRFLOW" : "",
1173 			 tp->pcomp_en ? " PCOMP" : "",
1174 			 tp->hold_mcs ? " HMCS" : "",
1175 			 tmp, tp->offset);
1176 	} else {
1177 		dev_info(&starget->dev, "%sasynchronous\n",
1178 				tp->width ? "wide " : "");
1179 	}
1180 }
1181 EXPORT_SYMBOL(spi_display_xfer_agreement);
1182 
1183 int spi_populate_width_msg(unsigned char *msg, int width)
1184 {
1185 	msg[0] = EXTENDED_MESSAGE;
1186 	msg[1] = 2;
1187 	msg[2] = EXTENDED_WDTR;
1188 	msg[3] = width;
1189 	return 4;
1190 }
1191 EXPORT_SYMBOL_GPL(spi_populate_width_msg);
1192 
1193 int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
1194 {
1195 	msg[0] = EXTENDED_MESSAGE;
1196 	msg[1] = 3;
1197 	msg[2] = EXTENDED_SDTR;
1198 	msg[3] = period;
1199 	msg[4] = offset;
1200 	return 5;
1201 }
1202 EXPORT_SYMBOL_GPL(spi_populate_sync_msg);
1203 
1204 int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
1205 		int width, int options)
1206 {
1207 	msg[0] = EXTENDED_MESSAGE;
1208 	msg[1] = 6;
1209 	msg[2] = EXTENDED_PPR;
1210 	msg[3] = period;
1211 	msg[4] = 0;
1212 	msg[5] = offset;
1213 	msg[6] = width;
1214 	msg[7] = options;
1215 	return 8;
1216 }
1217 EXPORT_SYMBOL_GPL(spi_populate_ppr_msg);
1218 
1219 /**
1220  * spi_populate_tag_msg - place a tag message in a buffer
1221  * @msg:	pointer to the area to place the tag
1222  * @cmd:	pointer to the scsi command for the tag
1223  *
1224  * Notes:
1225  *	designed to create the correct type of tag message for the
1226  *	particular request.  Returns the size of the tag message.
1227  *	May return 0 if TCQ is disabled for this device.
1228  **/
1229 int spi_populate_tag_msg(unsigned char *msg, struct scsi_cmnd *cmd)
1230 {
1231         if (cmd->flags & SCMD_TAGGED) {
1232 		*msg++ = SIMPLE_QUEUE_TAG;
1233 		*msg++ = scsi_cmd_to_rq(cmd)->tag;
1234         	return 2;
1235 	}
1236 
1237 	return 0;
1238 }
1239 EXPORT_SYMBOL_GPL(spi_populate_tag_msg);
1240 
1241 #ifdef CONFIG_SCSI_CONSTANTS
1242 static const char * const one_byte_msgs[] = {
1243 /* 0x00 */ "Task Complete", NULL /* Extended Message */, "Save Pointers",
1244 /* 0x03 */ "Restore Pointers", "Disconnect", "Initiator Error",
1245 /* 0x06 */ "Abort Task Set", "Message Reject", "Nop", "Message Parity Error",
1246 /* 0x0a */ "Linked Command Complete", "Linked Command Complete w/flag",
1247 /* 0x0c */ "Target Reset", "Abort Task", "Clear Task Set",
1248 /* 0x0f */ "Initiate Recovery", "Release Recovery",
1249 /* 0x11 */ "Terminate Process", "Continue Task", "Target Transfer Disable",
1250 /* 0x14 */ NULL, NULL, "Clear ACA", "LUN Reset"
1251 };
1252 
1253 static const char * const two_byte_msgs[] = {
1254 /* 0x20 */ "Simple Queue Tag", "Head of Queue Tag", "Ordered Queue Tag",
1255 /* 0x23 */ "Ignore Wide Residue", "ACA"
1256 };
1257 
1258 static const char * const extended_msgs[] = {
1259 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
1260 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
1261 /* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
1262 };
1263 
1264 static void print_nego(const unsigned char *msg, int per, int off, int width)
1265 {
1266 	if (per) {
1267 		char buf[20];
1268 		period_to_str(buf, msg[per]);
1269 		printk("period = %s ns ", buf);
1270 	}
1271 
1272 	if (off)
1273 		printk("offset = %d ", msg[off]);
1274 	if (width)
1275 		printk("width = %d ", 8 << msg[width]);
1276 }
1277 
1278 static void print_ptr(const unsigned char *msg, int msb, const char *desc)
1279 {
1280 	int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
1281 			msg[msb+3];
1282 	printk("%s = %d ", desc, ptr);
1283 }
1284 
1285 int spi_print_msg(const unsigned char *msg)
1286 {
1287 	int len = 1, i;
1288 	if (msg[0] == EXTENDED_MESSAGE) {
1289 		len = 2 + msg[1];
1290 		if (len == 2)
1291 			len += 256;
1292 		if (msg[2] < ARRAY_SIZE(extended_msgs))
1293 			printk ("%s ", extended_msgs[msg[2]]);
1294 		else
1295 			printk ("Extended Message, reserved code (0x%02x) ",
1296 				(int) msg[2]);
1297 		switch (msg[2]) {
1298 		case EXTENDED_MODIFY_DATA_POINTER:
1299 			print_ptr(msg, 3, "pointer");
1300 			break;
1301 		case EXTENDED_SDTR:
1302 			print_nego(msg, 3, 4, 0);
1303 			break;
1304 		case EXTENDED_WDTR:
1305 			print_nego(msg, 0, 0, 3);
1306 			break;
1307 		case EXTENDED_PPR:
1308 			print_nego(msg, 3, 5, 6);
1309 			break;
1310 		case EXTENDED_MODIFY_BIDI_DATA_PTR:
1311 			print_ptr(msg, 3, "out");
1312 			print_ptr(msg, 7, "in");
1313 			break;
1314 		default:
1315 		for (i = 2; i < len; ++i)
1316 			printk("%02x ", msg[i]);
1317 		}
1318 	/* Identify */
1319 	} else if (msg[0] & 0x80) {
1320 		printk("Identify disconnect %sallowed %s %d ",
1321 			(msg[0] & 0x40) ? "" : "not ",
1322 			(msg[0] & 0x20) ? "target routine" : "lun",
1323 			msg[0] & 0x7);
1324 	/* Normal One byte */
1325 	} else if (msg[0] < 0x1f) {
1326 		if (msg[0] < ARRAY_SIZE(one_byte_msgs) && one_byte_msgs[msg[0]])
1327 			printk("%s ", one_byte_msgs[msg[0]]);
1328 		else
1329 			printk("reserved (%02x) ", msg[0]);
1330 	} else if (msg[0] == 0x55) {
1331 		printk("QAS Request ");
1332 	/* Two byte */
1333 	} else if (msg[0] <= 0x2f) {
1334 		if ((msg[0] - 0x20) < ARRAY_SIZE(two_byte_msgs))
1335 			printk("%s %02x ", two_byte_msgs[msg[0] - 0x20],
1336 				msg[1]);
1337 		else
1338 			printk("reserved two byte (%02x %02x) ",
1339 				msg[0], msg[1]);
1340 		len = 2;
1341 	} else
1342 		printk("reserved ");
1343 	return len;
1344 }
1345 EXPORT_SYMBOL(spi_print_msg);
1346 
1347 #else  /* ifndef CONFIG_SCSI_CONSTANTS */
1348 
1349 int spi_print_msg(const unsigned char *msg)
1350 {
1351 	int len = 1, i;
1352 
1353 	if (msg[0] == EXTENDED_MESSAGE) {
1354 		len = 2 + msg[1];
1355 		if (len == 2)
1356 			len += 256;
1357 		for (i = 0; i < len; ++i)
1358 			printk("%02x ", msg[i]);
1359 	/* Identify */
1360 	} else if (msg[0] & 0x80) {
1361 		printk("%02x ", msg[0]);
1362 	/* Normal One byte */
1363 	} else if ((msg[0] < 0x1f) || (msg[0] == 0x55)) {
1364 		printk("%02x ", msg[0]);
1365 	/* Two byte */
1366 	} else if (msg[0] <= 0x2f) {
1367 		printk("%02x %02x", msg[0], msg[1]);
1368 		len = 2;
1369 	} else
1370 		printk("%02x ", msg[0]);
1371 	return len;
1372 }
1373 EXPORT_SYMBOL(spi_print_msg);
1374 #endif /* ! CONFIG_SCSI_CONSTANTS */
1375 
1376 static int spi_device_match(struct attribute_container *cont,
1377 			    struct device *dev)
1378 {
1379 	struct scsi_device *sdev;
1380 	struct Scsi_Host *shost;
1381 	struct spi_internal *i;
1382 
1383 	if (!scsi_is_sdev_device(dev))
1384 		return 0;
1385 
1386 	sdev = to_scsi_device(dev);
1387 	shost = sdev->host;
1388 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1389 	    != &spi_host_class.class)
1390 		return 0;
1391 	/* Note: this class has no device attributes, so it has
1392 	 * no per-HBA allocation and thus we don't need to distinguish
1393 	 * the attribute containers for the device */
1394 	i = to_spi_internal(shost->transportt);
1395 	if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1396 		return 0;
1397 	return 1;
1398 }
1399 
1400 static int spi_target_match(struct attribute_container *cont,
1401 			    struct device *dev)
1402 {
1403 	struct Scsi_Host *shost;
1404 	struct scsi_target *starget;
1405 	struct spi_internal *i;
1406 
1407 	if (!scsi_is_target_device(dev))
1408 		return 0;
1409 
1410 	shost = dev_to_shost(dev->parent);
1411 	if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1412 	    != &spi_host_class.class)
1413 		return 0;
1414 
1415 	i = to_spi_internal(shost->transportt);
1416 	starget = to_scsi_target(dev);
1417 
1418 	if (i->f->deny_binding && i->f->deny_binding(starget))
1419 		return 0;
1420 
1421 	return &i->t.target_attrs.ac == cont;
1422 }
1423 
1424 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1425 			       "spi_transport",
1426 			       spi_setup_transport_attrs,
1427 			       NULL,
1428 			       spi_target_configure);
1429 
1430 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1431 				    spi_device_match,
1432 				    spi_device_configure);
1433 
1434 static struct attribute *host_attributes[] = {
1435 	&dev_attr_signalling.attr,
1436 	&dev_attr_host_width.attr,
1437 	&dev_attr_hba_id.attr,
1438 	NULL
1439 };
1440 
1441 static struct attribute_group host_attribute_group = {
1442 	.attrs = host_attributes,
1443 };
1444 
1445 static int spi_host_configure(struct transport_container *tc,
1446 			      struct device *dev,
1447 			      struct device *cdev)
1448 {
1449 	struct kobject *kobj = &cdev->kobj;
1450 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1451 	struct spi_internal *si = to_spi_internal(shost->transportt);
1452 	struct attribute *attr = &dev_attr_signalling.attr;
1453 	int rc = 0;
1454 
1455 	if (si->f->set_signalling)
1456 		rc = sysfs_chmod_file(kobj, attr, attr->mode | S_IWUSR);
1457 
1458 	return rc;
1459 }
1460 
1461 /* returns true if we should be showing the variable.  Also
1462  * overloads the return by setting 1<<1 if the attribute should
1463  * be writeable */
1464 #define TARGET_ATTRIBUTE_HELPER(name) \
1465 	(si->f->show_##name ? S_IRUGO : 0) | \
1466 	(si->f->set_##name ? S_IWUSR : 0)
1467 
1468 static umode_t target_attribute_is_visible(struct kobject *kobj,
1469 					  struct attribute *attr, int i)
1470 {
1471 	struct device *cdev = container_of(kobj, struct device, kobj);
1472 	struct scsi_target *starget = transport_class_to_starget(cdev);
1473 	struct Scsi_Host *shost = transport_class_to_shost(cdev);
1474 	struct spi_internal *si = to_spi_internal(shost->transportt);
1475 
1476 	if (attr == &dev_attr_period.attr &&
1477 	    spi_support_sync(starget))
1478 		return TARGET_ATTRIBUTE_HELPER(period);
1479 	else if (attr == &dev_attr_min_period.attr &&
1480 		 spi_support_sync(starget))
1481 		return TARGET_ATTRIBUTE_HELPER(period);
1482 	else if (attr == &dev_attr_offset.attr &&
1483 		 spi_support_sync(starget))
1484 		return TARGET_ATTRIBUTE_HELPER(offset);
1485 	else if (attr == &dev_attr_max_offset.attr &&
1486 		 spi_support_sync(starget))
1487 		return TARGET_ATTRIBUTE_HELPER(offset);
1488 	else if (attr == &dev_attr_width.attr &&
1489 		 spi_support_wide(starget))
1490 		return TARGET_ATTRIBUTE_HELPER(width);
1491 	else if (attr == &dev_attr_max_width.attr &&
1492 		 spi_support_wide(starget))
1493 		return TARGET_ATTRIBUTE_HELPER(width);
1494 	else if (attr == &dev_attr_iu.attr &&
1495 		 spi_support_ius(starget))
1496 		return TARGET_ATTRIBUTE_HELPER(iu);
1497 	else if (attr == &dev_attr_max_iu.attr &&
1498 		 spi_support_ius(starget))
1499 		return TARGET_ATTRIBUTE_HELPER(iu);
1500 	else if (attr == &dev_attr_dt.attr &&
1501 		 spi_support_dt(starget))
1502 		return TARGET_ATTRIBUTE_HELPER(dt);
1503 	else if (attr == &dev_attr_qas.attr &&
1504 		 spi_support_qas(starget))
1505 		return TARGET_ATTRIBUTE_HELPER(qas);
1506 	else if (attr == &dev_attr_max_qas.attr &&
1507 		 spi_support_qas(starget))
1508 		return TARGET_ATTRIBUTE_HELPER(qas);
1509 	else if (attr == &dev_attr_wr_flow.attr &&
1510 		 spi_support_ius(starget))
1511 		return TARGET_ATTRIBUTE_HELPER(wr_flow);
1512 	else if (attr == &dev_attr_rd_strm.attr &&
1513 		 spi_support_ius(starget))
1514 		return TARGET_ATTRIBUTE_HELPER(rd_strm);
1515 	else if (attr == &dev_attr_rti.attr &&
1516 		 spi_support_ius(starget))
1517 		return TARGET_ATTRIBUTE_HELPER(rti);
1518 	else if (attr == &dev_attr_pcomp_en.attr &&
1519 		 spi_support_ius(starget))
1520 		return TARGET_ATTRIBUTE_HELPER(pcomp_en);
1521 	else if (attr == &dev_attr_hold_mcs.attr &&
1522 		 spi_support_ius(starget))
1523 		return TARGET_ATTRIBUTE_HELPER(hold_mcs);
1524 	else if (attr == &dev_attr_revalidate.attr)
1525 		return S_IWUSR;
1526 
1527 	return 0;
1528 }
1529 
1530 static struct attribute *target_attributes[] = {
1531 	&dev_attr_period.attr,
1532 	&dev_attr_min_period.attr,
1533 	&dev_attr_offset.attr,
1534 	&dev_attr_max_offset.attr,
1535 	&dev_attr_width.attr,
1536 	&dev_attr_max_width.attr,
1537 	&dev_attr_iu.attr,
1538 	&dev_attr_max_iu.attr,
1539 	&dev_attr_dt.attr,
1540 	&dev_attr_qas.attr,
1541 	&dev_attr_max_qas.attr,
1542 	&dev_attr_wr_flow.attr,
1543 	&dev_attr_rd_strm.attr,
1544 	&dev_attr_rti.attr,
1545 	&dev_attr_pcomp_en.attr,
1546 	&dev_attr_hold_mcs.attr,
1547 	&dev_attr_revalidate.attr,
1548 	NULL
1549 };
1550 
1551 static struct attribute_group target_attribute_group = {
1552 	.attrs = target_attributes,
1553 	.is_visible = target_attribute_is_visible,
1554 };
1555 
1556 static int spi_target_configure(struct transport_container *tc,
1557 				struct device *dev,
1558 				struct device *cdev)
1559 {
1560 	struct kobject *kobj = &cdev->kobj;
1561 
1562 	/* force an update based on parameters read from the device */
1563 	sysfs_update_group(kobj, &target_attribute_group);
1564 
1565 	return 0;
1566 }
1567 
1568 struct scsi_transport_template *
1569 spi_attach_transport(struct spi_function_template *ft)
1570 {
1571 	struct spi_internal *i = kzalloc(sizeof(struct spi_internal),
1572 					 GFP_KERNEL);
1573 
1574 	if (unlikely(!i))
1575 		return NULL;
1576 
1577 	i->t.target_attrs.ac.class = &spi_transport_class.class;
1578 	i->t.target_attrs.ac.grp = &target_attribute_group;
1579 	i->t.target_attrs.ac.match = spi_target_match;
1580 	transport_container_register(&i->t.target_attrs);
1581 	i->t.target_size = sizeof(struct spi_transport_attrs);
1582 	i->t.host_attrs.ac.class = &spi_host_class.class;
1583 	i->t.host_attrs.ac.grp = &host_attribute_group;
1584 	i->t.host_attrs.ac.match = spi_host_match;
1585 	transport_container_register(&i->t.host_attrs);
1586 	i->t.host_size = sizeof(struct spi_host_attrs);
1587 	i->f = ft;
1588 
1589 	return &i->t;
1590 }
1591 EXPORT_SYMBOL(spi_attach_transport);
1592 
1593 void spi_release_transport(struct scsi_transport_template *t)
1594 {
1595 	struct spi_internal *i = to_spi_internal(t);
1596 
1597 	transport_container_unregister(&i->t.target_attrs);
1598 	transport_container_unregister(&i->t.host_attrs);
1599 
1600 	kfree(i);
1601 }
1602 EXPORT_SYMBOL(spi_release_transport);
1603 
1604 static __init int spi_transport_init(void)
1605 {
1606 	int error = scsi_dev_info_add_list(SCSI_DEVINFO_SPI,
1607 					   "SCSI Parallel Transport Class");
1608 	if (!error) {
1609 		int i;
1610 
1611 		for (i = 0; spi_static_device_list[i].vendor; i++)
1612 			scsi_dev_info_list_add_keyed(1,	/* compatible */
1613 						     spi_static_device_list[i].vendor,
1614 						     spi_static_device_list[i].model,
1615 						     NULL,
1616 						     spi_static_device_list[i].flags,
1617 						     SCSI_DEVINFO_SPI);
1618 	}
1619 
1620 	error = transport_class_register(&spi_transport_class);
1621 	if (error)
1622 		return error;
1623 	error = anon_transport_class_register(&spi_device_class);
1624 	return transport_class_register(&spi_host_class);
1625 }
1626 
1627 static void __exit spi_transport_exit(void)
1628 {
1629 	transport_class_unregister(&spi_transport_class);
1630 	anon_transport_class_unregister(&spi_device_class);
1631 	transport_class_unregister(&spi_host_class);
1632 	scsi_dev_info_remove_list(SCSI_DEVINFO_SPI);
1633 }
1634 
1635 MODULE_AUTHOR("Martin Hicks");
1636 MODULE_DESCRIPTION("SPI Transport Attributes");
1637 MODULE_LICENSE("GPL");
1638 
1639 module_init(spi_transport_init);
1640 module_exit(spi_transport_exit);
1641