Merge commit 'v2.6.28-rc9' into next
[linux-2.6] / drivers / scsi / scsi_transport_spi.c
1 /* 
2  *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
3  *
4  *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
5  *  Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 #include <linux/ctype.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/workqueue.h>
25 #include <linux/blkdev.h>
26 #include <linux/mutex.h>
27 #include <linux/sysfs.h>
28 #include <scsi/scsi.h>
29 #include "scsi_priv.h"
30 #include <scsi/scsi_device.h>
31 #include <scsi/scsi_host.h>
32 #include <scsi/scsi_cmnd.h>
33 #include <scsi/scsi_eh.h>
34 #include <scsi/scsi_transport.h>
35 #include <scsi/scsi_transport_spi.h>
36
37 #define SPI_NUM_ATTRS 14        /* increase this if you add attributes */
38 #define SPI_OTHER_ATTRS 1       /* Increase this if you add "always
39                                  * on" attributes */
40 #define SPI_HOST_ATTRS  1
41
42 #define SPI_MAX_ECHO_BUFFER_SIZE        4096
43
44 #define DV_LOOPS        3
45 #define DV_TIMEOUT      (10*HZ)
46 #define DV_RETRIES      3       /* should only need at most 
47                                  * two cc/ua clears */
48
49 /* Private data accessors (keep these out of the header file) */
50 #define spi_dv_in_progress(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_in_progress)
51 #define spi_dv_mutex(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_mutex)
52
53 struct spi_internal {
54         struct scsi_transport_template t;
55         struct spi_function_template *f;
56 };
57
58 #define to_spi_internal(tmpl)   container_of(tmpl, struct spi_internal, t)
59
60 static const int ppr_to_ps[] = {
61         /* The PPR values 0-6 are reserved, fill them in when
62          * the committee defines them */
63         -1,                     /* 0x00 */
64         -1,                     /* 0x01 */
65         -1,                     /* 0x02 */
66         -1,                     /* 0x03 */
67         -1,                     /* 0x04 */
68         -1,                     /* 0x05 */
69         -1,                     /* 0x06 */
70          3125,                  /* 0x07 */
71          6250,                  /* 0x08 */
72         12500,                  /* 0x09 */
73         25000,                  /* 0x0a */
74         30300,                  /* 0x0b */
75         50000,                  /* 0x0c */
76 };
77 /* The PPR values at which you calculate the period in ns by multiplying
78  * by 4 */
79 #define SPI_STATIC_PPR  0x0c
80
81 static int sprint_frac(char *dest, int value, int denom)
82 {
83         int frac = value % denom;
84         int result = sprintf(dest, "%d", value / denom);
85
86         if (frac == 0)
87                 return result;
88         dest[result++] = '.';
89
90         do {
91                 denom /= 10;
92                 sprintf(dest + result, "%d", frac / denom);
93                 result++;
94                 frac %= denom;
95         } while (frac);
96
97         dest[result++] = '\0';
98         return result;
99 }
100
101 static int spi_execute(struct scsi_device *sdev, const void *cmd,
102                        enum dma_data_direction dir,
103                        void *buffer, unsigned bufflen,
104                        struct scsi_sense_hdr *sshdr)
105 {
106         int i, result;
107         unsigned char sense[SCSI_SENSE_BUFFERSIZE];
108
109         for(i = 0; i < DV_RETRIES; i++) {
110                 result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
111                                       sense, DV_TIMEOUT, /* retries */ 1,
112                                       REQ_FAILFAST_DEV |
113                                       REQ_FAILFAST_TRANSPORT |
114                                       REQ_FAILFAST_DRIVER);
115                 if (result & DRIVER_SENSE) {
116                         struct scsi_sense_hdr sshdr_tmp;
117                         if (!sshdr)
118                                 sshdr = &sshdr_tmp;
119
120                         if (scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE,
121                                                  sshdr)
122                             && sshdr->sense_key == UNIT_ATTENTION)
123                                 continue;
124                 }
125                 break;
126         }
127         return result;
128 }
129
130 static struct {
131         enum spi_signal_type    value;
132         char                    *name;
133 } signal_types[] = {
134         { SPI_SIGNAL_UNKNOWN, "unknown" },
135         { SPI_SIGNAL_SE, "SE" },
136         { SPI_SIGNAL_LVD, "LVD" },
137         { SPI_SIGNAL_HVD, "HVD" },
138 };
139
140 static inline const char *spi_signal_to_string(enum spi_signal_type type)
141 {
142         int i;
143
144         for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
145                 if (type == signal_types[i].value)
146                         return signal_types[i].name;
147         }
148         return NULL;
149 }
150 static inline enum spi_signal_type spi_signal_to_value(const char *name)
151 {
152         int i, len;
153
154         for (i = 0; i < ARRAY_SIZE(signal_types); i++) {
155                 len =  strlen(signal_types[i].name);
156                 if (strncmp(name, signal_types[i].name, len) == 0 &&
157                     (name[len] == '\n' || name[len] == '\0'))
158                         return signal_types[i].value;
159         }
160         return SPI_SIGNAL_UNKNOWN;
161 }
162
163 static int spi_host_setup(struct transport_container *tc, struct device *dev,
164                           struct device *cdev)
165 {
166         struct Scsi_Host *shost = dev_to_shost(dev);
167
168         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
169
170         return 0;
171 }
172
173 static int spi_host_configure(struct transport_container *tc,
174                               struct device *dev,
175                               struct device *cdev);
176
177 static DECLARE_TRANSPORT_CLASS(spi_host_class,
178                                "spi_host",
179                                spi_host_setup,
180                                NULL,
181                                spi_host_configure);
182
183 static int spi_host_match(struct attribute_container *cont,
184                           struct device *dev)
185 {
186         struct Scsi_Host *shost;
187
188         if (!scsi_is_host_device(dev))
189                 return 0;
190
191         shost = dev_to_shost(dev);
192         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
193             != &spi_host_class.class)
194                 return 0;
195
196         return &shost->transportt->host_attrs.ac == cont;
197 }
198
199 static int spi_target_configure(struct transport_container *tc,
200                                 struct device *dev,
201                                 struct device *cdev);
202
203 static int spi_device_configure(struct transport_container *tc,
204                                 struct device *dev,
205                                 struct device *cdev)
206 {
207         struct scsi_device *sdev = to_scsi_device(dev);
208         struct scsi_target *starget = sdev->sdev_target;
209
210         /* Populate the target capability fields with the values
211          * gleaned from the device inquiry */
212
213         spi_support_sync(starget) = scsi_device_sync(sdev);
214         spi_support_wide(starget) = scsi_device_wide(sdev);
215         spi_support_dt(starget) = scsi_device_dt(sdev);
216         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
217         spi_support_ius(starget) = scsi_device_ius(sdev);
218         spi_support_qas(starget) = scsi_device_qas(sdev);
219
220         return 0;
221 }
222
223 static int spi_setup_transport_attrs(struct transport_container *tc,
224                                      struct device *dev,
225                                      struct device *cdev)
226 {
227         struct scsi_target *starget = to_scsi_target(dev);
228
229         spi_period(starget) = -1;       /* illegal value */
230         spi_min_period(starget) = 0;
231         spi_offset(starget) = 0;        /* async */
232         spi_max_offset(starget) = 255;
233         spi_width(starget) = 0; /* narrow */
234         spi_max_width(starget) = 1;
235         spi_iu(starget) = 0;    /* no IU */
236         spi_dt(starget) = 0;    /* ST */
237         spi_qas(starget) = 0;
238         spi_wr_flow(starget) = 0;
239         spi_rd_strm(starget) = 0;
240         spi_rti(starget) = 0;
241         spi_pcomp_en(starget) = 0;
242         spi_hold_mcs(starget) = 0;
243         spi_dv_pending(starget) = 0;
244         spi_dv_in_progress(starget) = 0;
245         spi_initial_dv(starget) = 0;
246         mutex_init(&spi_dv_mutex(starget));
247
248         return 0;
249 }
250
251 #define spi_transport_show_simple(field, format_string)                 \
252                                                                         \
253 static ssize_t                                                          \
254 show_spi_transport_##field(struct device *dev,                  \
255                            struct device_attribute *attr, char *buf)    \
256 {                                                                       \
257         struct scsi_target *starget = transport_class_to_starget(dev);  \
258         struct spi_transport_attrs *tp;                                 \
259                                                                         \
260         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
261         return snprintf(buf, 20, format_string, tp->field);             \
262 }
263
264 #define spi_transport_store_simple(field, format_string)                \
265                                                                         \
266 static ssize_t                                                          \
267 store_spi_transport_##field(struct device *dev,                         \
268                             struct device_attribute *attr,              \
269                             const char *buf, size_t count)              \
270 {                                                                       \
271         int val;                                                        \
272         struct scsi_target *starget = transport_class_to_starget(dev);  \
273         struct spi_transport_attrs *tp;                                 \
274                                                                         \
275         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
276         val = simple_strtoul(buf, NULL, 0);                             \
277         tp->field = val;                                                \
278         return count;                                                   \
279 }
280
281 #define spi_transport_show_function(field, format_string)               \
282                                                                         \
283 static ssize_t                                                          \
284 show_spi_transport_##field(struct device *dev,                  \
285                            struct device_attribute *attr, char *buf)    \
286 {                                                                       \
287         struct scsi_target *starget = transport_class_to_starget(dev);  \
288         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
289         struct spi_transport_attrs *tp;                                 \
290         struct spi_internal *i = to_spi_internal(shost->transportt);    \
291         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
292         if (i->f->get_##field)                                          \
293                 i->f->get_##field(starget);                             \
294         return snprintf(buf, 20, format_string, tp->field);             \
295 }
296
297 #define spi_transport_store_function(field, format_string)              \
298 static ssize_t                                                          \
299 store_spi_transport_##field(struct device *dev,                         \
300                             struct device_attribute *attr,              \
301                             const char *buf, size_t count)              \
302 {                                                                       \
303         int val;                                                        \
304         struct scsi_target *starget = transport_class_to_starget(dev);  \
305         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
306         struct spi_internal *i = to_spi_internal(shost->transportt);    \
307                                                                         \
308         if (!i->f->set_##field)                                         \
309                 return -EINVAL;                                         \
310         val = simple_strtoul(buf, NULL, 0);                             \
311         i->f->set_##field(starget, val);                                \
312         return count;                                                   \
313 }
314
315 #define spi_transport_store_max(field, format_string)                   \
316 static ssize_t                                                          \
317 store_spi_transport_##field(struct device *dev,                         \
318                             struct device_attribute *attr,              \
319                             const char *buf, size_t count)              \
320 {                                                                       \
321         int val;                                                        \
322         struct scsi_target *starget = transport_class_to_starget(dev);  \
323         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
324         struct spi_internal *i = to_spi_internal(shost->transportt);    \
325         struct spi_transport_attrs *tp                                  \
326                 = (struct spi_transport_attrs *)&starget->starget_data; \
327                                                                         \
328         if (i->f->set_##field)                                          \
329                 return -EINVAL;                                         \
330         val = simple_strtoul(buf, NULL, 0);                             \
331         if (val > tp->max_##field)                                      \
332                 val = tp->max_##field;                                  \
333         i->f->set_##field(starget, val);                                \
334         return count;                                                   \
335 }
336
337 #define spi_transport_rd_attr(field, format_string)                     \
338         spi_transport_show_function(field, format_string)               \
339         spi_transport_store_function(field, format_string)              \
340 static DEVICE_ATTR(field, S_IRUGO,                              \
341                    show_spi_transport_##field,                  \
342                    store_spi_transport_##field);
343
344 #define spi_transport_simple_attr(field, format_string)                 \
345         spi_transport_show_simple(field, format_string)                 \
346         spi_transport_store_simple(field, format_string)                \
347 static DEVICE_ATTR(field, S_IRUGO,                              \
348                    show_spi_transport_##field,                  \
349                    store_spi_transport_##field);
350
351 #define spi_transport_max_attr(field, format_string)                    \
352         spi_transport_show_function(field, format_string)               \
353         spi_transport_store_max(field, format_string)                   \
354         spi_transport_simple_attr(max_##field, format_string)           \
355 static DEVICE_ATTR(field, S_IRUGO,                              \
356                    show_spi_transport_##field,                  \
357                    store_spi_transport_##field);
358
359 /* The Parallel SCSI Tranport Attributes: */
360 spi_transport_max_attr(offset, "%d\n");
361 spi_transport_max_attr(width, "%d\n");
362 spi_transport_rd_attr(iu, "%d\n");
363 spi_transport_rd_attr(dt, "%d\n");
364 spi_transport_rd_attr(qas, "%d\n");
365 spi_transport_rd_attr(wr_flow, "%d\n");
366 spi_transport_rd_attr(rd_strm, "%d\n");
367 spi_transport_rd_attr(rti, "%d\n");
368 spi_transport_rd_attr(pcomp_en, "%d\n");
369 spi_transport_rd_attr(hold_mcs, "%d\n");
370
371 /* we only care about the first child device that's a real SCSI device
372  * so we return 1 to terminate the iteration when we find it */
373 static int child_iter(struct device *dev, void *data)
374 {
375         if (!scsi_is_sdev_device(dev))
376                 return 0;
377
378         spi_dv_device(to_scsi_device(dev));
379         return 1;
380 }
381
382 static ssize_t
383 store_spi_revalidate(struct device *dev, struct device_attribute *attr,
384                      const char *buf, size_t count)
385 {
386         struct scsi_target *starget = transport_class_to_starget(dev);
387
388         device_for_each_child(&starget->dev, NULL, child_iter);
389         return count;
390 }
391 static DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
392
393 /* Translate the period into ns according to the current spec
394  * for SDTR/PPR messages */
395 static int period_to_str(char *buf, int period)
396 {
397         int len, picosec;
398
399         if (period < 0 || period > 0xff) {
400                 picosec = -1;
401         } else if (period <= SPI_STATIC_PPR) {
402                 picosec = ppr_to_ps[period];
403         } else {
404                 picosec = period * 4000;
405         }
406
407         if (picosec == -1) {
408                 len = sprintf(buf, "reserved");
409         } else {
410                 len = sprint_frac(buf, picosec, 1000);
411         }
412
413         return len;
414 }
415
416 static ssize_t
417 show_spi_transport_period_helper(char *buf, int period)
418 {
419         int len = period_to_str(buf, period);
420         buf[len++] = '\n';
421         buf[len] = '\0';
422         return len;
423 }
424
425 static ssize_t
426 store_spi_transport_period_helper(struct device *dev, const char *buf,
427                                   size_t count, int *periodp)
428 {
429         int j, picosec, period = -1;
430         char *endp;
431
432         picosec = simple_strtoul(buf, &endp, 10) * 1000;
433         if (*endp == '.') {
434                 int mult = 100;
435                 do {
436                         endp++;
437                         if (!isdigit(*endp))
438                                 break;
439                         picosec += (*endp - '0') * mult;
440                         mult /= 10;
441                 } while (mult > 0);
442         }
443
444         for (j = 0; j <= SPI_STATIC_PPR; j++) {
445                 if (ppr_to_ps[j] < picosec)
446                         continue;
447                 period = j;
448                 break;
449         }
450
451         if (period == -1)
452                 period = picosec / 4000;
453
454         if (period > 0xff)
455                 period = 0xff;
456
457         *periodp = period;
458
459         return count;
460 }
461
462 static ssize_t
463 show_spi_transport_period(struct device *dev,
464                           struct device_attribute *attr, char *buf)
465 {
466         struct scsi_target *starget = transport_class_to_starget(dev);
467         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
468         struct spi_internal *i = to_spi_internal(shost->transportt);
469         struct spi_transport_attrs *tp =
470                 (struct spi_transport_attrs *)&starget->starget_data;
471
472         if (i->f->get_period)
473                 i->f->get_period(starget);
474
475         return show_spi_transport_period_helper(buf, tp->period);
476 }
477
478 static ssize_t
479 store_spi_transport_period(struct device *cdev, struct device_attribute *attr,
480                            const char *buf, size_t count)
481 {
482         struct scsi_target *starget = transport_class_to_starget(cdev);
483         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
484         struct spi_internal *i = to_spi_internal(shost->transportt);
485         struct spi_transport_attrs *tp =
486                 (struct spi_transport_attrs *)&starget->starget_data;
487         int period, retval;
488
489         if (!i->f->set_period)
490                 return -EINVAL;
491
492         retval = store_spi_transport_period_helper(cdev, buf, count, &period);
493
494         if (period < tp->min_period)
495                 period = tp->min_period;
496
497         i->f->set_period(starget, period);
498
499         return retval;
500 }
501
502 static DEVICE_ATTR(period, S_IRUGO,
503                    show_spi_transport_period,
504                    store_spi_transport_period);
505
506 static ssize_t
507 show_spi_transport_min_period(struct device *cdev,
508                               struct device_attribute *attr, char *buf)
509 {
510         struct scsi_target *starget = transport_class_to_starget(cdev);
511         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
512         struct spi_internal *i = to_spi_internal(shost->transportt);
513         struct spi_transport_attrs *tp =
514                 (struct spi_transport_attrs *)&starget->starget_data;
515
516         if (!i->f->set_period)
517                 return -EINVAL;
518
519         return show_spi_transport_period_helper(buf, tp->min_period);
520 }
521
522 static ssize_t
523 store_spi_transport_min_period(struct device *cdev,
524                                struct device_attribute *attr,
525                                const char *buf, size_t count)
526 {
527         struct scsi_target *starget = transport_class_to_starget(cdev);
528         struct spi_transport_attrs *tp =
529                 (struct spi_transport_attrs *)&starget->starget_data;
530
531         return store_spi_transport_period_helper(cdev, buf, count,
532                                                  &tp->min_period);
533 }
534
535
536 static DEVICE_ATTR(min_period, S_IRUGO,
537                    show_spi_transport_min_period,
538                    store_spi_transport_min_period);
539
540
541 static ssize_t show_spi_host_signalling(struct device *cdev,
542                                         struct device_attribute *attr,
543                                         char *buf)
544 {
545         struct Scsi_Host *shost = transport_class_to_shost(cdev);
546         struct spi_internal *i = to_spi_internal(shost->transportt);
547
548         if (i->f->get_signalling)
549                 i->f->get_signalling(shost);
550
551         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
552 }
553 static ssize_t store_spi_host_signalling(struct device *dev,
554                                          struct device_attribute *attr,
555                                          const char *buf, size_t count)
556 {
557         struct Scsi_Host *shost = transport_class_to_shost(dev);
558         struct spi_internal *i = to_spi_internal(shost->transportt);
559         enum spi_signal_type type = spi_signal_to_value(buf);
560
561         if (!i->f->set_signalling)
562                 return -EINVAL;
563
564         if (type != SPI_SIGNAL_UNKNOWN)
565                 i->f->set_signalling(shost, type);
566
567         return count;
568 }
569 static DEVICE_ATTR(signalling, S_IRUGO,
570                    show_spi_host_signalling,
571                    store_spi_host_signalling);
572
573 #define DV_SET(x, y)                    \
574         if(i->f->set_##x)               \
575                 i->f->set_##x(sdev->sdev_target, y)
576
577 enum spi_compare_returns {
578         SPI_COMPARE_SUCCESS,
579         SPI_COMPARE_FAILURE,
580         SPI_COMPARE_SKIP_TEST,
581 };
582
583
584 /* This is for read/write Domain Validation:  If the device supports
585  * an echo buffer, we do read/write tests to it */
586 static enum spi_compare_returns
587 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
588                           u8 *ptr, const int retries)
589 {
590         int len = ptr - buffer;
591         int j, k, r, result;
592         unsigned int pattern = 0x0000ffff;
593         struct scsi_sense_hdr sshdr;
594
595         const char spi_write_buffer[] = {
596                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
597         };
598         const char spi_read_buffer[] = {
599                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
600         };
601
602         /* set up the pattern buffer.  Doesn't matter if we spill
603          * slightly beyond since that's where the read buffer is */
604         for (j = 0; j < len; ) {
605
606                 /* fill the buffer with counting (test a) */
607                 for ( ; j < min(len, 32); j++)
608                         buffer[j] = j;
609                 k = j;
610                 /* fill the buffer with alternating words of 0x0 and
611                  * 0xffff (test b) */
612                 for ( ; j < min(len, k + 32); j += 2) {
613                         u16 *word = (u16 *)&buffer[j];
614                         
615                         *word = (j & 0x02) ? 0x0000 : 0xffff;
616                 }
617                 k = j;
618                 /* fill with crosstalk (alternating 0x5555 0xaaa)
619                  * (test c) */
620                 for ( ; j < min(len, k + 32); j += 2) {
621                         u16 *word = (u16 *)&buffer[j];
622
623                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
624                 }
625                 k = j;
626                 /* fill with shifting bits (test d) */
627                 for ( ; j < min(len, k + 32); j += 4) {
628                         u32 *word = (unsigned int *)&buffer[j];
629                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
630                         
631                         *word = pattern;
632                         pattern = (pattern << 1) | roll;
633                 }
634                 /* don't bother with random data (test e) */
635         }
636
637         for (r = 0; r < retries; r++) {
638                 result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
639                                      buffer, len, &sshdr);
640                 if(result || !scsi_device_online(sdev)) {
641
642                         scsi_device_set_state(sdev, SDEV_QUIESCE);
643                         if (scsi_sense_valid(&sshdr)
644                             && sshdr.sense_key == ILLEGAL_REQUEST
645                             /* INVALID FIELD IN CDB */
646                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
647                                 /* This would mean that the drive lied
648                                  * to us about supporting an echo
649                                  * buffer (unfortunately some Western
650                                  * Digital drives do precisely this)
651                                  */
652                                 return SPI_COMPARE_SKIP_TEST;
653
654
655                         sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
656                         return SPI_COMPARE_FAILURE;
657                 }
658
659                 memset(ptr, 0, len);
660                 spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
661                             ptr, len, NULL);
662                 scsi_device_set_state(sdev, SDEV_QUIESCE);
663
664                 if (memcmp(buffer, ptr, len) != 0)
665                         return SPI_COMPARE_FAILURE;
666         }
667         return SPI_COMPARE_SUCCESS;
668 }
669
670 /* This is for the simplest form of Domain Validation: a read test
671  * on the inquiry data from the device */
672 static enum spi_compare_returns
673 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
674                               u8 *ptr, const int retries)
675 {
676         int r, result;
677         const int len = sdev->inquiry_len;
678         const char spi_inquiry[] = {
679                 INQUIRY, 0, 0, 0, len, 0
680         };
681
682         for (r = 0; r < retries; r++) {
683                 memset(ptr, 0, len);
684
685                 result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
686                                      ptr, len, NULL);
687                 
688                 if(result || !scsi_device_online(sdev)) {
689                         scsi_device_set_state(sdev, SDEV_QUIESCE);
690                         return SPI_COMPARE_FAILURE;
691                 }
692
693                 /* If we don't have the inquiry data already, the
694                  * first read gets it */
695                 if (ptr == buffer) {
696                         ptr += len;
697                         --r;
698                         continue;
699                 }
700
701                 if (memcmp(buffer, ptr, len) != 0)
702                         /* failure */
703                         return SPI_COMPARE_FAILURE;
704         }
705         return SPI_COMPARE_SUCCESS;
706 }
707
708 static enum spi_compare_returns
709 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
710                enum spi_compare_returns 
711                (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
712 {
713         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
714         struct scsi_target *starget = sdev->sdev_target;
715         int period = 0, prevperiod = 0; 
716         enum spi_compare_returns retval;
717
718
719         for (;;) {
720                 int newperiod;
721                 retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
722
723                 if (retval == SPI_COMPARE_SUCCESS
724                     || retval == SPI_COMPARE_SKIP_TEST)
725                         break;
726
727                 /* OK, retrain, fallback */
728                 if (i->f->get_iu)
729                         i->f->get_iu(starget);
730                 if (i->f->get_qas)
731                         i->f->get_qas(starget);
732                 if (i->f->get_period)
733                         i->f->get_period(sdev->sdev_target);
734
735                 /* Here's the fallback sequence; first try turning off
736                  * IU, then QAS (if we can control them), then finally
737                  * fall down the periods */
738                 if (i->f->set_iu && spi_iu(starget)) {
739                         starget_printk(KERN_ERR, starget, "Domain Validation Disabing Information Units\n");
740                         DV_SET(iu, 0);
741                 } else if (i->f->set_qas && spi_qas(starget)) {
742                         starget_printk(KERN_ERR, starget, "Domain Validation Disabing Quick Arbitration and Selection\n");
743                         DV_SET(qas, 0);
744                 } else {
745                         newperiod = spi_period(starget);
746                         period = newperiod > period ? newperiod : period;
747                         if (period < 0x0d)
748                                 period++;
749                         else
750                                 period += period >> 1;
751
752                         if (unlikely(period > 0xff || period == prevperiod)) {
753                                 /* Total failure; set to async and return */
754                                 starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
755                                 DV_SET(offset, 0);
756                                 return SPI_COMPARE_FAILURE;
757                         }
758                         starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
759                         DV_SET(period, period);
760                         prevperiod = period;
761                 }
762         }
763         return retval;
764 }
765
766 static int
767 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
768 {
769         int l, result;
770
771         /* first off do a test unit ready.  This can error out 
772          * because of reservations or some other reason.  If it
773          * fails, the device won't let us write to the echo buffer
774          * so just return failure */
775         
776         const char spi_test_unit_ready[] = {
777                 TEST_UNIT_READY, 0, 0, 0, 0, 0
778         };
779
780         const char spi_read_buffer_descriptor[] = {
781                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
782         };
783
784         
785         /* We send a set of three TURs to clear any outstanding 
786          * unit attention conditions if they exist (Otherwise the
787          * buffer tests won't be happy).  If the TUR still fails
788          * (reservation conflict, device not ready, etc) just
789          * skip the write tests */
790         for (l = 0; ; l++) {
791                 result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE, 
792                                      NULL, 0, NULL);
793
794                 if(result) {
795                         if(l >= 3)
796                                 return 0;
797                 } else {
798                         /* TUR succeeded */
799                         break;
800                 }
801         }
802
803         result = spi_execute(sdev, spi_read_buffer_descriptor, 
804                              DMA_FROM_DEVICE, buffer, 4, NULL);
805
806         if (result)
807                 /* Device has no echo buffer */
808                 return 0;
809
810         return buffer[3] + ((buffer[2] & 0x1f) << 8);
811 }
812
813 static void
814 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
815 {
816         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
817         struct scsi_target *starget = sdev->sdev_target;
818         struct Scsi_Host *shost = sdev->host;
819         int len = sdev->inquiry_len;
820         int min_period = spi_min_period(starget);
821         int max_width = spi_max_width(starget);
822         /* first set us up for narrow async */
823         DV_SET(offset, 0);
824         DV_SET(width, 0);
825
826         if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
827             != SPI_COMPARE_SUCCESS) {
828                 starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
829                 /* FIXME: should probably offline the device here? */
830                 return;
831         }
832
833         if (!scsi_device_wide(sdev)) {
834                 spi_max_width(starget) = 0;
835                 max_width = 0;
836         }
837
838         /* test width */
839         if (i->f->set_width && max_width) {
840                 i->f->set_width(starget, 1);
841
842                 if (spi_dv_device_compare_inquiry(sdev, buffer,
843                                                    buffer + len,
844                                                    DV_LOOPS)
845                     != SPI_COMPARE_SUCCESS) {
846                         starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
847                         i->f->set_width(starget, 0);
848                         /* Make sure we don't force wide back on by asking
849                          * for a transfer period that requires it */
850                         max_width = 0;
851                         if (min_period < 10)
852                                 min_period = 10;
853                 }
854         }
855
856         if (!i->f->set_period)
857                 return;
858
859         /* device can't handle synchronous */
860         if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
861                 return;
862
863         /* len == -1 is the signal that we need to ascertain the
864          * presence of an echo buffer before trying to use it.  len ==
865          * 0 means we don't have an echo buffer */
866         len = -1;
867
868  retry:
869
870         /* now set up to the maximum */
871         DV_SET(offset, spi_max_offset(starget));
872         DV_SET(period, min_period);
873
874         /* try QAS requests; this should be harmless to set if the
875          * target supports it */
876         if (scsi_device_qas(sdev)) {
877                 DV_SET(qas, 1);
878         } else {
879                 DV_SET(qas, 0);
880         }
881
882         if (scsi_device_ius(sdev) && min_period < 9) {
883                 /* This u320 (or u640). Set IU transfers */
884                 DV_SET(iu, 1);
885                 /* Then set the optional parameters */
886                 DV_SET(rd_strm, 1);
887                 DV_SET(wr_flow, 1);
888                 DV_SET(rti, 1);
889                 if (min_period == 8)
890                         DV_SET(pcomp_en, 1);
891         } else {
892                 DV_SET(iu, 0);
893         }
894
895         /* now that we've done all this, actually check the bus
896          * signal type (if known).  Some devices are stupid on
897          * a SE bus and still claim they can try LVD only settings */
898         if (i->f->get_signalling)
899                 i->f->get_signalling(shost);
900         if (spi_signalling(shost) == SPI_SIGNAL_SE ||
901             spi_signalling(shost) == SPI_SIGNAL_HVD ||
902             !scsi_device_dt(sdev)) {
903                 DV_SET(dt, 0);
904         } else {
905                 DV_SET(dt, 1);
906         }
907         /* set width last because it will pull all the other
908          * parameters down to required values */
909         DV_SET(width, max_width);
910
911         /* Do the read only INQUIRY tests */
912         spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
913                        spi_dv_device_compare_inquiry);
914         /* See if we actually managed to negotiate and sustain DT */
915         if (i->f->get_dt)
916                 i->f->get_dt(starget);
917
918         /* see if the device has an echo buffer.  If it does we can do
919          * the SPI pattern write tests.  Because of some broken
920          * devices, we *only* try this on a device that has actually
921          * negotiated DT */
922
923         if (len == -1 && spi_dt(starget))
924                 len = spi_dv_device_get_echo_buffer(sdev, buffer);
925
926         if (len <= 0) {
927                 starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
928                 return;
929         }
930
931         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
932                 starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
933                 len = SPI_MAX_ECHO_BUFFER_SIZE;
934         }
935
936         if (spi_dv_retrain(sdev, buffer, buffer + len,
937                            spi_dv_device_echo_buffer)
938             == SPI_COMPARE_SKIP_TEST) {
939                 /* OK, the stupid drive can't do a write echo buffer
940                  * test after all, fall back to the read tests */
941                 len = 0;
942                 goto retry;
943         }
944 }
945
946
947 /**     spi_dv_device - Do Domain Validation on the device
948  *      @sdev:          scsi device to validate
949  *
950  *      Performs the domain validation on the given device in the
951  *      current execution thread.  Since DV operations may sleep,
952  *      the current thread must have user context.  Also no SCSI
953  *      related locks that would deadlock I/O issued by the DV may
954  *      be held.
955  */
956 void
957 spi_dv_device(struct scsi_device *sdev)
958 {
959         struct scsi_target *starget = sdev->sdev_target;
960         u8 *buffer;
961         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
962
963         if (unlikely(scsi_device_get(sdev)))
964                 return;
965
966         if (unlikely(spi_dv_in_progress(starget)))
967                 return;
968         spi_dv_in_progress(starget) = 1;
969
970         buffer = kzalloc(len, GFP_KERNEL);
971
972         if (unlikely(!buffer))
973                 goto out_put;
974
975         /* We need to verify that the actual device will quiesce; the
976          * later target quiesce is just a nice to have */
977         if (unlikely(scsi_device_quiesce(sdev)))
978                 goto out_free;
979
980         scsi_target_quiesce(starget);
981
982         spi_dv_pending(starget) = 1;
983         mutex_lock(&spi_dv_mutex(starget));
984
985         starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
986
987         spi_dv_device_internal(sdev, buffer);
988
989         starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
990
991         mutex_unlock(&spi_dv_mutex(starget));
992         spi_dv_pending(starget) = 0;
993
994         scsi_target_resume(starget);
995
996         spi_initial_dv(starget) = 1;
997
998  out_free:
999         kfree(buffer);
1000  out_put:
1001         spi_dv_in_progress(starget) = 0;
1002         scsi_device_put(sdev);
1003 }
1004 EXPORT_SYMBOL(spi_dv_device);
1005
1006 struct work_queue_wrapper {
1007         struct work_struct      work;
1008         struct scsi_device      *sdev;
1009 };
1010
1011 static void
1012 spi_dv_device_work_wrapper(struct work_struct *work)
1013 {
1014         struct work_queue_wrapper *wqw =
1015                 container_of(work, struct work_queue_wrapper, work);
1016         struct scsi_device *sdev = wqw->sdev;
1017
1018         kfree(wqw);
1019         spi_dv_device(sdev);
1020         spi_dv_pending(sdev->sdev_target) = 0;
1021         scsi_device_put(sdev);
1022 }
1023
1024
1025 /**
1026  *      spi_schedule_dv_device - schedule domain validation to occur on the device
1027  *      @sdev:  The device to validate
1028  *
1029  *      Identical to spi_dv_device() above, except that the DV will be
1030  *      scheduled to occur in a workqueue later.  All memory allocations
1031  *      are atomic, so may be called from any context including those holding
1032  *      SCSI locks.
1033  */
1034 void
1035 spi_schedule_dv_device(struct scsi_device *sdev)
1036 {
1037         struct work_queue_wrapper *wqw =
1038                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
1039
1040         if (unlikely(!wqw))
1041                 return;
1042
1043         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
1044                 kfree(wqw);
1045                 return;
1046         }
1047         /* Set pending early (dv_device doesn't check it, only sets it) */
1048         spi_dv_pending(sdev->sdev_target) = 1;
1049         if (unlikely(scsi_device_get(sdev))) {
1050                 kfree(wqw);
1051                 spi_dv_pending(sdev->sdev_target) = 0;
1052                 return;
1053         }
1054
1055         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper);
1056         wqw->sdev = sdev;
1057
1058         schedule_work(&wqw->work);
1059 }
1060 EXPORT_SYMBOL(spi_schedule_dv_device);
1061
1062 /**
1063  * spi_display_xfer_agreement - Print the current target transfer agreement
1064  * @starget: The target for which to display the agreement
1065  *
1066  * Each SPI port is required to maintain a transfer agreement for each
1067  * other port on the bus.  This function prints a one-line summary of
1068  * the current agreement; more detailed information is available in sysfs.
1069  */
1070 void spi_display_xfer_agreement(struct scsi_target *starget)
1071 {
1072         struct spi_transport_attrs *tp;
1073         tp = (struct spi_transport_attrs *)&starget->starget_data;
1074
1075         if (tp->offset > 0 && tp->period > 0) {
1076                 unsigned int picosec, kb100;
1077                 char *scsi = "FAST-?";
1078                 char tmp[8];
1079
1080                 if (tp->period <= SPI_STATIC_PPR) {
1081                         picosec = ppr_to_ps[tp->period];
1082                         switch (tp->period) {
1083                                 case  7: scsi = "FAST-320"; break;
1084                                 case  8: scsi = "FAST-160"; break;
1085                                 case  9: scsi = "FAST-80"; break;
1086                                 case 10:
1087                                 case 11: scsi = "FAST-40"; break;
1088                                 case 12: scsi = "FAST-20"; break;
1089                         }
1090                 } else {
1091                         picosec = tp->period * 4000;
1092                         if (tp->period < 25)
1093                                 scsi = "FAST-20";
1094                         else if (tp->period < 50)
1095                                 scsi = "FAST-10";
1096                         else
1097                                 scsi = "FAST-5";
1098                 }
1099
1100                 kb100 = (10000000 + picosec / 2) / picosec;
1101                 if (tp->width)
1102                         kb100 *= 2;
1103                 sprint_frac(tmp, picosec, 1000);
1104
1105                 dev_info(&starget->dev,
1106                          "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1107                          scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1108                          tp->dt ? "DT" : "ST",
1109                          tp->iu ? " IU" : "",
1110                          tp->qas  ? " QAS" : "",
1111                          tp->rd_strm ? " RDSTRM" : "",
1112                          tp->rti ? " RTI" : "",
1113                          tp->wr_flow ? " WRFLOW" : "",
1114                          tp->pcomp_en ? " PCOMP" : "",
1115                          tp->hold_mcs ? " HMCS" : "",
1116                          tmp, tp->offset);
1117         } else {
1118                 dev_info(&starget->dev, "%sasynchronous\n",
1119                                 tp->width ? "wide " : "");
1120         }
1121 }
1122 EXPORT_SYMBOL(spi_display_xfer_agreement);
1123
1124 int spi_populate_width_msg(unsigned char *msg, int width)
1125 {
1126         msg[0] = EXTENDED_MESSAGE;
1127         msg[1] = 2;
1128         msg[2] = EXTENDED_WDTR;
1129         msg[3] = width;
1130         return 4;
1131 }
1132 EXPORT_SYMBOL_GPL(spi_populate_width_msg);
1133
1134 int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
1135 {
1136         msg[0] = EXTENDED_MESSAGE;
1137         msg[1] = 3;
1138         msg[2] = EXTENDED_SDTR;
1139         msg[3] = period;
1140         msg[4] = offset;
1141         return 5;
1142 }
1143 EXPORT_SYMBOL_GPL(spi_populate_sync_msg);
1144
1145 int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
1146                 int width, int options)
1147 {
1148         msg[0] = EXTENDED_MESSAGE;
1149         msg[1] = 6;
1150         msg[2] = EXTENDED_PPR;
1151         msg[3] = period;
1152         msg[4] = 0;
1153         msg[5] = offset;
1154         msg[6] = width;
1155         msg[7] = options;
1156         return 8;
1157 }
1158 EXPORT_SYMBOL_GPL(spi_populate_ppr_msg);
1159
1160 #ifdef CONFIG_SCSI_CONSTANTS
1161 static const char * const one_byte_msgs[] = {
1162 /* 0x00 */ "Task Complete", NULL /* Extended Message */, "Save Pointers",
1163 /* 0x03 */ "Restore Pointers", "Disconnect", "Initiator Error", 
1164 /* 0x06 */ "Abort Task Set", "Message Reject", "Nop", "Message Parity Error",
1165 /* 0x0a */ "Linked Command Complete", "Linked Command Complete w/flag",
1166 /* 0x0c */ "Target Reset", "Abort Task", "Clear Task Set", 
1167 /* 0x0f */ "Initiate Recovery", "Release Recovery",
1168 /* 0x11 */ "Terminate Process", "Continue Task", "Target Transfer Disable",
1169 /* 0x14 */ NULL, NULL, "Clear ACA", "LUN Reset"
1170 };
1171
1172 static const char * const two_byte_msgs[] = {
1173 /* 0x20 */ "Simple Queue Tag", "Head of Queue Tag", "Ordered Queue Tag",
1174 /* 0x23 */ "Ignore Wide Residue", "ACA"
1175 };
1176
1177 static const char * const extended_msgs[] = {
1178 /* 0x00 */ "Modify Data Pointer", "Synchronous Data Transfer Request",
1179 /* 0x02 */ "SCSI-I Extended Identify", "Wide Data Transfer Request",
1180 /* 0x04 */ "Parallel Protocol Request", "Modify Bidirectional Data Pointer"
1181 };
1182
1183 static void print_nego(const unsigned char *msg, int per, int off, int width)
1184 {
1185         if (per) {
1186                 char buf[20];
1187                 period_to_str(buf, msg[per]);
1188                 printk("period = %s ns ", buf);
1189         }
1190
1191         if (off)
1192                 printk("offset = %d ", msg[off]);
1193         if (width)
1194                 printk("width = %d ", 8 << msg[width]);
1195 }
1196
1197 static void print_ptr(const unsigned char *msg, int msb, const char *desc)
1198 {
1199         int ptr = (msg[msb] << 24) | (msg[msb+1] << 16) | (msg[msb+2] << 8) |
1200                         msg[msb+3];
1201         printk("%s = %d ", desc, ptr);
1202 }
1203
1204 int spi_print_msg(const unsigned char *msg)
1205 {
1206         int len = 1, i;
1207         if (msg[0] == EXTENDED_MESSAGE) {
1208                 len = 2 + msg[1];
1209                 if (len == 2)
1210                         len += 256;
1211                 if (msg[2] < ARRAY_SIZE(extended_msgs))
1212                         printk ("%s ", extended_msgs[msg[2]]); 
1213                 else 
1214                         printk ("Extended Message, reserved code (0x%02x) ",
1215                                 (int) msg[2]);
1216                 switch (msg[2]) {
1217                 case EXTENDED_MODIFY_DATA_POINTER:
1218                         print_ptr(msg, 3, "pointer");
1219                         break;
1220                 case EXTENDED_SDTR:
1221                         print_nego(msg, 3, 4, 0);
1222                         break;
1223                 case EXTENDED_WDTR:
1224                         print_nego(msg, 0, 0, 3);
1225                         break;
1226                 case EXTENDED_PPR:
1227                         print_nego(msg, 3, 5, 6);
1228                         break;
1229                 case EXTENDED_MODIFY_BIDI_DATA_PTR:
1230                         print_ptr(msg, 3, "out");
1231                         print_ptr(msg, 7, "in");
1232                         break;
1233                 default:
1234                 for (i = 2; i < len; ++i) 
1235                         printk("%02x ", msg[i]);
1236                 }
1237         /* Identify */
1238         } else if (msg[0] & 0x80) {
1239                 printk("Identify disconnect %sallowed %s %d ",
1240                         (msg[0] & 0x40) ? "" : "not ",
1241                         (msg[0] & 0x20) ? "target routine" : "lun",
1242                         msg[0] & 0x7);
1243         /* Normal One byte */
1244         } else if (msg[0] < 0x1f) {
1245                 if (msg[0] < ARRAY_SIZE(one_byte_msgs) && one_byte_msgs[msg[0]])
1246                         printk("%s ", one_byte_msgs[msg[0]]);
1247                 else
1248                         printk("reserved (%02x) ", msg[0]);
1249         } else if (msg[0] == 0x55) {
1250                 printk("QAS Request ");
1251         /* Two byte */
1252         } else if (msg[0] <= 0x2f) {
1253                 if ((msg[0] - 0x20) < ARRAY_SIZE(two_byte_msgs))
1254                         printk("%s %02x ", two_byte_msgs[msg[0] - 0x20], 
1255                                 msg[1]);
1256                 else 
1257                         printk("reserved two byte (%02x %02x) ", 
1258                                 msg[0], msg[1]);
1259                 len = 2;
1260         } else 
1261                 printk("reserved ");
1262         return len;
1263 }
1264 EXPORT_SYMBOL(spi_print_msg);
1265
1266 #else  /* ifndef CONFIG_SCSI_CONSTANTS */
1267
1268 int spi_print_msg(const unsigned char *msg)
1269 {
1270         int len = 1, i;
1271
1272         if (msg[0] == EXTENDED_MESSAGE) {
1273                 len = 2 + msg[1];
1274                 if (len == 2)
1275                         len += 256;
1276                 for (i = 0; i < len; ++i)
1277                         printk("%02x ", msg[i]);
1278         /* Identify */
1279         } else if (msg[0] & 0x80) {
1280                 printk("%02x ", msg[0]);
1281         /* Normal One byte */
1282         } else if ((msg[0] < 0x1f) || (msg[0] == 0x55)) {
1283                 printk("%02x ", msg[0]);
1284         /* Two byte */
1285         } else if (msg[0] <= 0x2f) {
1286                 printk("%02x %02x", msg[0], msg[1]);
1287                 len = 2;
1288         } else 
1289                 printk("%02x ", msg[0]);
1290         return len;
1291 }
1292 EXPORT_SYMBOL(spi_print_msg);
1293 #endif /* ! CONFIG_SCSI_CONSTANTS */
1294
1295 static int spi_device_match(struct attribute_container *cont,
1296                             struct device *dev)
1297 {
1298         struct scsi_device *sdev;
1299         struct Scsi_Host *shost;
1300         struct spi_internal *i;
1301
1302         if (!scsi_is_sdev_device(dev))
1303                 return 0;
1304
1305         sdev = to_scsi_device(dev);
1306         shost = sdev->host;
1307         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1308             != &spi_host_class.class)
1309                 return 0;
1310         /* Note: this class has no device attributes, so it has
1311          * no per-HBA allocation and thus we don't need to distinguish
1312          * the attribute containers for the device */
1313         i = to_spi_internal(shost->transportt);
1314         if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1315                 return 0;
1316         return 1;
1317 }
1318
1319 static int spi_target_match(struct attribute_container *cont,
1320                             struct device *dev)
1321 {
1322         struct Scsi_Host *shost;
1323         struct scsi_target *starget;
1324         struct spi_internal *i;
1325
1326         if (!scsi_is_target_device(dev))
1327                 return 0;
1328
1329         shost = dev_to_shost(dev->parent);
1330         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1331             != &spi_host_class.class)
1332                 return 0;
1333
1334         i = to_spi_internal(shost->transportt);
1335         starget = to_scsi_target(dev);
1336
1337         if (i->f->deny_binding && i->f->deny_binding(starget))
1338                 return 0;
1339
1340         return &i->t.target_attrs.ac == cont;
1341 }
1342
1343 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1344                                "spi_transport",
1345                                spi_setup_transport_attrs,
1346                                NULL,
1347                                spi_target_configure);
1348
1349 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1350                                     spi_device_match,
1351                                     spi_device_configure);
1352
1353 static struct attribute *host_attributes[] = {
1354         &dev_attr_signalling.attr,
1355         NULL
1356 };
1357
1358 static struct attribute_group host_attribute_group = {
1359         .attrs = host_attributes,
1360 };
1361
1362 static int spi_host_configure(struct transport_container *tc,
1363                               struct device *dev,
1364                               struct device *cdev)
1365 {
1366         struct kobject *kobj = &cdev->kobj;
1367         struct Scsi_Host *shost = transport_class_to_shost(cdev);
1368         struct spi_internal *si = to_spi_internal(shost->transportt);
1369         struct attribute *attr = &dev_attr_signalling.attr;
1370         int rc = 0;
1371
1372         if (si->f->set_signalling)
1373                 rc = sysfs_chmod_file(kobj, attr, attr->mode | S_IWUSR);
1374
1375         return rc;
1376 }
1377
1378 /* returns true if we should be showing the variable.  Also
1379  * overloads the return by setting 1<<1 if the attribute should
1380  * be writeable */
1381 #define TARGET_ATTRIBUTE_HELPER(name) \
1382         (si->f->show_##name ? S_IRUGO : 0) | \
1383         (si->f->set_##name ? S_IWUSR : 0)
1384
1385 static mode_t target_attribute_is_visible(struct kobject *kobj,
1386                                           struct attribute *attr, int i)
1387 {
1388         struct device *cdev = container_of(kobj, struct device, kobj);
1389         struct scsi_target *starget = transport_class_to_starget(cdev);
1390         struct Scsi_Host *shost = transport_class_to_shost(cdev);
1391         struct spi_internal *si = to_spi_internal(shost->transportt);
1392
1393         if (attr == &dev_attr_period.attr &&
1394             spi_support_sync(starget))
1395                 return TARGET_ATTRIBUTE_HELPER(period);
1396         else if (attr == &dev_attr_min_period.attr &&
1397                  spi_support_sync(starget))
1398                 return TARGET_ATTRIBUTE_HELPER(period);
1399         else if (attr == &dev_attr_offset.attr &&
1400                  spi_support_sync(starget))
1401                 return TARGET_ATTRIBUTE_HELPER(offset);
1402         else if (attr == &dev_attr_max_offset.attr &&
1403                  spi_support_sync(starget))
1404                 return TARGET_ATTRIBUTE_HELPER(offset);
1405         else if (attr == &dev_attr_width.attr &&
1406                  spi_support_wide(starget))
1407                 return TARGET_ATTRIBUTE_HELPER(width);
1408         else if (attr == &dev_attr_max_width.attr &&
1409                  spi_support_wide(starget))
1410                 return TARGET_ATTRIBUTE_HELPER(width);
1411         else if (attr == &dev_attr_iu.attr &&
1412                  spi_support_ius(starget))
1413                 return TARGET_ATTRIBUTE_HELPER(iu);
1414         else if (attr == &dev_attr_dt.attr &&
1415                  spi_support_dt(starget))
1416                 return TARGET_ATTRIBUTE_HELPER(dt);
1417         else if (attr == &dev_attr_qas.attr &&
1418                  spi_support_qas(starget))
1419                 return TARGET_ATTRIBUTE_HELPER(qas);
1420         else if (attr == &dev_attr_wr_flow.attr &&
1421                  spi_support_ius(starget))
1422                 return TARGET_ATTRIBUTE_HELPER(wr_flow);
1423         else if (attr == &dev_attr_rd_strm.attr &&
1424                  spi_support_ius(starget))
1425                 return TARGET_ATTRIBUTE_HELPER(rd_strm);
1426         else if (attr == &dev_attr_rti.attr &&
1427                  spi_support_ius(starget))
1428                 return TARGET_ATTRIBUTE_HELPER(rti);
1429         else if (attr == &dev_attr_pcomp_en.attr &&
1430                  spi_support_ius(starget))
1431                 return TARGET_ATTRIBUTE_HELPER(pcomp_en);
1432         else if (attr == &dev_attr_hold_mcs.attr &&
1433                  spi_support_ius(starget))
1434                 return TARGET_ATTRIBUTE_HELPER(hold_mcs);
1435         else if (attr == &dev_attr_revalidate.attr)
1436                 return S_IWUSR;
1437
1438         return 0;
1439 }
1440
1441 static struct attribute *target_attributes[] = {
1442         &dev_attr_period.attr,
1443         &dev_attr_min_period.attr,
1444         &dev_attr_offset.attr,
1445         &dev_attr_max_offset.attr,
1446         &dev_attr_width.attr,
1447         &dev_attr_max_width.attr,
1448         &dev_attr_iu.attr,
1449         &dev_attr_dt.attr,
1450         &dev_attr_qas.attr,
1451         &dev_attr_wr_flow.attr,
1452         &dev_attr_rd_strm.attr,
1453         &dev_attr_rti.attr,
1454         &dev_attr_pcomp_en.attr,
1455         &dev_attr_hold_mcs.attr,
1456         &dev_attr_revalidate.attr,
1457         NULL
1458 };
1459
1460 static struct attribute_group target_attribute_group = {
1461         .attrs = target_attributes,
1462         .is_visible = target_attribute_is_visible,
1463 };
1464
1465 static int spi_target_configure(struct transport_container *tc,
1466                                 struct device *dev,
1467                                 struct device *cdev)
1468 {
1469         struct kobject *kobj = &cdev->kobj;
1470
1471         /* force an update based on parameters read from the device */
1472         sysfs_update_group(kobj, &target_attribute_group);
1473
1474         return 0;
1475 }
1476
1477 struct scsi_transport_template *
1478 spi_attach_transport(struct spi_function_template *ft)
1479 {
1480         struct spi_internal *i = kzalloc(sizeof(struct spi_internal),
1481                                          GFP_KERNEL);
1482
1483         if (unlikely(!i))
1484                 return NULL;
1485
1486         i->t.target_attrs.ac.class = &spi_transport_class.class;
1487         i->t.target_attrs.ac.grp = &target_attribute_group;
1488         i->t.target_attrs.ac.match = spi_target_match;
1489         transport_container_register(&i->t.target_attrs);
1490         i->t.target_size = sizeof(struct spi_transport_attrs);
1491         i->t.host_attrs.ac.class = &spi_host_class.class;
1492         i->t.host_attrs.ac.grp = &host_attribute_group;
1493         i->t.host_attrs.ac.match = spi_host_match;
1494         transport_container_register(&i->t.host_attrs);
1495         i->t.host_size = sizeof(struct spi_host_attrs);
1496         i->f = ft;
1497
1498         return &i->t;
1499 }
1500 EXPORT_SYMBOL(spi_attach_transport);
1501
1502 void spi_release_transport(struct scsi_transport_template *t)
1503 {
1504         struct spi_internal *i = to_spi_internal(t);
1505
1506         transport_container_unregister(&i->t.target_attrs);
1507         transport_container_unregister(&i->t.host_attrs);
1508
1509         kfree(i);
1510 }
1511 EXPORT_SYMBOL(spi_release_transport);
1512
1513 static __init int spi_transport_init(void)
1514 {
1515         int error = transport_class_register(&spi_transport_class);
1516         if (error)
1517                 return error;
1518         error = anon_transport_class_register(&spi_device_class);
1519         return transport_class_register(&spi_host_class);
1520 }
1521
1522 static void __exit spi_transport_exit(void)
1523 {
1524         transport_class_unregister(&spi_transport_class);
1525         anon_transport_class_unregister(&spi_device_class);
1526         transport_class_unregister(&spi_host_class);
1527 }
1528
1529 MODULE_AUTHOR("Martin Hicks");
1530 MODULE_DESCRIPTION("SPI Transport Attributes");
1531 MODULE_LICENSE("GPL");
1532
1533 module_init(spi_transport_init);
1534 module_exit(spi_transport_exit);