[SCSI] Delete trailing full stop
[linux-2.6.git] / 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 <asm/semaphore.h>
27 #include <scsi/scsi.h>
28 #include "scsi_priv.h"
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_transport_spi.h>
35
36 #define SPI_NUM_ATTRS 14        /* increase this if you add attributes */
37 #define SPI_OTHER_ATTRS 1       /* Increase this if you add "always
38                                  * on" attributes */
39 #define SPI_HOST_ATTRS  1
40
41 #define SPI_MAX_ECHO_BUFFER_SIZE        4096
42
43 #define DV_LOOPS        3
44 #define DV_TIMEOUT      (10*HZ)
45 #define DV_RETRIES      3       /* should only need at most 
46                                  * two cc/ua clears */
47
48 /* Private data accessors (keep these out of the header file) */
49 #define spi_dv_pending(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_pending)
50 #define spi_dv_sem(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_sem)
51
52 struct spi_internal {
53         struct scsi_transport_template t;
54         struct spi_function_template *f;
55         /* The actual attributes */
56         struct class_device_attribute private_attrs[SPI_NUM_ATTRS];
57         /* The array of null terminated pointers to attributes 
58          * needed by scsi_sysfs.c */
59         struct class_device_attribute *attrs[SPI_NUM_ATTRS + SPI_OTHER_ATTRS + 1];
60         struct class_device_attribute private_host_attrs[SPI_HOST_ATTRS];
61         struct class_device_attribute *host_attrs[SPI_HOST_ATTRS + 1];
62 };
63
64 #define to_spi_internal(tmpl)   container_of(tmpl, struct spi_internal, t)
65
66 static const int ppr_to_ps[] = {
67         /* The PPR values 0-6 are reserved, fill them in when
68          * the committee defines them */
69         -1,                     /* 0x00 */
70         -1,                     /* 0x01 */
71         -1,                     /* 0x02 */
72         -1,                     /* 0x03 */
73         -1,                     /* 0x04 */
74         -1,                     /* 0x05 */
75         -1,                     /* 0x06 */
76          3125,                  /* 0x07 */
77          6250,                  /* 0x08 */
78         12500,                  /* 0x09 */
79         25000,                  /* 0x0a */
80         30300,                  /* 0x0b */
81         50000,                  /* 0x0c */
82 };
83 /* The PPR values at which you calculate the period in ns by multiplying
84  * by 4 */
85 #define SPI_STATIC_PPR  0x0c
86
87 static int sprint_frac(char *dest, int value, int denom)
88 {
89         int frac = value % denom;
90         int result = sprintf(dest, "%d", value / denom);
91
92         if (frac == 0)
93                 return result;
94         dest[result++] = '.';
95
96         do {
97                 denom /= 10;
98                 sprintf(dest + result, "%d", frac / denom);
99                 result++;
100                 frac %= denom;
101         } while (frac);
102
103         dest[result++] = '\0';
104         return result;
105 }
106
107 static int spi_execute(struct scsi_device *sdev, const void *cmd,
108                        enum dma_data_direction dir,
109                        void *buffer, unsigned bufflen,
110                        struct scsi_sense_hdr *sshdr)
111 {
112         int i, result;
113         unsigned char sense[SCSI_SENSE_BUFFERSIZE];
114
115         for(i = 0; i < DV_RETRIES; i++) {
116                 result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
117                                       sense, DV_TIMEOUT, /* retries */ 1,
118                                       REQ_FAILFAST);
119                 if (result & DRIVER_SENSE) {
120                         struct scsi_sense_hdr sshdr_tmp;
121                         if (!sshdr)
122                                 sshdr = &sshdr_tmp;
123
124                         if (scsi_normalize_sense(sense, sizeof(*sense),
125                                                  sshdr)
126                             && sshdr->sense_key == UNIT_ATTENTION)
127                                 continue;
128                 }
129                 break;
130         }
131         return result;
132 }
133
134 static struct {
135         enum spi_signal_type    value;
136         char                    *name;
137 } signal_types[] = {
138         { SPI_SIGNAL_UNKNOWN, "unknown" },
139         { SPI_SIGNAL_SE, "SE" },
140         { SPI_SIGNAL_LVD, "LVD" },
141         { SPI_SIGNAL_HVD, "HVD" },
142 };
143
144 static inline const char *spi_signal_to_string(enum spi_signal_type type)
145 {
146         int i;
147
148         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
149                 if (type == signal_types[i].value)
150                         return signal_types[i].name;
151         }
152         return NULL;
153 }
154 static inline enum spi_signal_type spi_signal_to_value(const char *name)
155 {
156         int i, len;
157
158         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
159                 len =  strlen(signal_types[i].name);
160                 if (strncmp(name, signal_types[i].name, len) == 0 &&
161                     (name[len] == '\n' || name[len] == '\0'))
162                         return signal_types[i].value;
163         }
164         return SPI_SIGNAL_UNKNOWN;
165 }
166
167 static int spi_host_setup(struct transport_container *tc, struct device *dev,
168                           struct class_device *cdev)
169 {
170         struct Scsi_Host *shost = dev_to_shost(dev);
171
172         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
173
174         return 0;
175 }
176
177 static DECLARE_TRANSPORT_CLASS(spi_host_class,
178                                "spi_host",
179                                spi_host_setup,
180                                NULL,
181                                NULL);
182
183 static int spi_host_match(struct attribute_container *cont,
184                           struct device *dev)
185 {
186         struct Scsi_Host *shost;
187         struct spi_internal *i;
188
189         if (!scsi_is_host_device(dev))
190                 return 0;
191
192         shost = dev_to_shost(dev);
193         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
194             != &spi_host_class.class)
195                 return 0;
196
197         i = to_spi_internal(shost->transportt);
198         
199         return &i->t.host_attrs.ac == cont;
200 }
201
202 static int spi_device_configure(struct transport_container *tc,
203                                 struct device *dev,
204                                 struct class_device *cdev)
205 {
206         struct scsi_device *sdev = to_scsi_device(dev);
207         struct scsi_target *starget = sdev->sdev_target;
208
209         /* Populate the target capability fields with the values
210          * gleaned from the device inquiry */
211
212         spi_support_sync(starget) = scsi_device_sync(sdev);
213         spi_support_wide(starget) = scsi_device_wide(sdev);
214         spi_support_dt(starget) = scsi_device_dt(sdev);
215         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
216         spi_support_ius(starget) = scsi_device_ius(sdev);
217         spi_support_qas(starget) = scsi_device_qas(sdev);
218
219         return 0;
220 }
221
222 static int spi_setup_transport_attrs(struct transport_container *tc,
223                                      struct device *dev,
224                                      struct class_device *cdev)
225 {
226         struct scsi_target *starget = to_scsi_target(dev);
227
228         spi_period(starget) = -1;       /* illegal value */
229         spi_min_period(starget) = 0;
230         spi_offset(starget) = 0;        /* async */
231         spi_max_offset(starget) = 255;
232         spi_width(starget) = 0; /* narrow */
233         spi_max_width(starget) = 1;
234         spi_iu(starget) = 0;    /* no IU */
235         spi_dt(starget) = 0;    /* ST */
236         spi_qas(starget) = 0;
237         spi_wr_flow(starget) = 0;
238         spi_rd_strm(starget) = 0;
239         spi_rti(starget) = 0;
240         spi_pcomp_en(starget) = 0;
241         spi_hold_mcs(starget) = 0;
242         spi_dv_pending(starget) = 0;
243         spi_initial_dv(starget) = 0;
244         init_MUTEX(&spi_dv_sem(starget));
245
246         return 0;
247 }
248
249 #define spi_transport_show_simple(field, format_string)                 \
250                                                                         \
251 static ssize_t                                                          \
252 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
253 {                                                                       \
254         struct scsi_target *starget = transport_class_to_starget(cdev); \
255         struct spi_transport_attrs *tp;                                 \
256                                                                         \
257         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
258         return snprintf(buf, 20, format_string, tp->field);             \
259 }
260
261 #define spi_transport_store_simple(field, format_string)                \
262                                                                         \
263 static ssize_t                                                          \
264 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
265                             size_t count)                               \
266 {                                                                       \
267         int val;                                                        \
268         struct scsi_target *starget = transport_class_to_starget(cdev); \
269         struct spi_transport_attrs *tp;                                 \
270                                                                         \
271         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
272         val = simple_strtoul(buf, NULL, 0);                             \
273         tp->field = val;                                                \
274         return count;                                                   \
275 }
276
277 #define spi_transport_show_function(field, format_string)               \
278                                                                         \
279 static ssize_t                                                          \
280 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
281 {                                                                       \
282         struct scsi_target *starget = transport_class_to_starget(cdev); \
283         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
284         struct spi_transport_attrs *tp;                                 \
285         struct spi_internal *i = to_spi_internal(shost->transportt);    \
286         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
287         if (i->f->get_##field)                                          \
288                 i->f->get_##field(starget);                             \
289         return snprintf(buf, 20, format_string, tp->field);             \
290 }
291
292 #define spi_transport_store_function(field, format_string)              \
293 static ssize_t                                                          \
294 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
295                             size_t count)                               \
296 {                                                                       \
297         int val;                                                        \
298         struct scsi_target *starget = transport_class_to_starget(cdev); \
299         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
300         struct spi_internal *i = to_spi_internal(shost->transportt);    \
301                                                                         \
302         val = simple_strtoul(buf, NULL, 0);                             \
303         i->f->set_##field(starget, val);                        \
304         return count;                                                   \
305 }
306
307 #define spi_transport_store_max(field, format_string)                   \
308 static ssize_t                                                          \
309 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
310                             size_t count)                               \
311 {                                                                       \
312         int val;                                                        \
313         struct scsi_target *starget = transport_class_to_starget(cdev); \
314         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
315         struct spi_internal *i = to_spi_internal(shost->transportt);    \
316         struct spi_transport_attrs *tp                                  \
317                 = (struct spi_transport_attrs *)&starget->starget_data; \
318                                                                         \
319         val = simple_strtoul(buf, NULL, 0);                             \
320         if (val > tp->max_##field)                                      \
321                 val = tp->max_##field;                                  \
322         i->f->set_##field(starget, val);                                \
323         return count;                                                   \
324 }
325
326 #define spi_transport_rd_attr(field, format_string)                     \
327         spi_transport_show_function(field, format_string)               \
328         spi_transport_store_function(field, format_string)              \
329 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
330                          show_spi_transport_##field,                    \
331                          store_spi_transport_##field);
332
333 #define spi_transport_simple_attr(field, format_string)                 \
334         spi_transport_show_simple(field, format_string)                 \
335         spi_transport_store_simple(field, format_string)                \
336 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
337                          show_spi_transport_##field,                    \
338                          store_spi_transport_##field);
339
340 #define spi_transport_max_attr(field, format_string)                    \
341         spi_transport_show_function(field, format_string)               \
342         spi_transport_store_max(field, format_string)                   \
343         spi_transport_simple_attr(max_##field, format_string)           \
344 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
345                          show_spi_transport_##field,                    \
346                          store_spi_transport_##field);
347
348 /* The Parallel SCSI Tranport Attributes: */
349 spi_transport_max_attr(offset, "%d\n");
350 spi_transport_max_attr(width, "%d\n");
351 spi_transport_rd_attr(iu, "%d\n");
352 spi_transport_rd_attr(dt, "%d\n");
353 spi_transport_rd_attr(qas, "%d\n");
354 spi_transport_rd_attr(wr_flow, "%d\n");
355 spi_transport_rd_attr(rd_strm, "%d\n");
356 spi_transport_rd_attr(rti, "%d\n");
357 spi_transport_rd_attr(pcomp_en, "%d\n");
358 spi_transport_rd_attr(hold_mcs, "%d\n");
359
360 /* we only care about the first child device so we return 1 */
361 static int child_iter(struct device *dev, void *data)
362 {
363         struct scsi_device *sdev = to_scsi_device(dev);
364
365         spi_dv_device(sdev);
366         return 1;
367 }
368
369 static ssize_t
370 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
371 {
372         struct scsi_target *starget = transport_class_to_starget(cdev);
373
374         device_for_each_child(&starget->dev, NULL, child_iter);
375         return count;
376 }
377 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
378
379 /* Translate the period into ns according to the current spec
380  * for SDTR/PPR messages */
381 static ssize_t
382 show_spi_transport_period_helper(struct class_device *cdev, char *buf,
383                                  int period)
384 {
385         int len, picosec;
386
387         if (period < 0 || period > 0xff) {
388                 picosec = -1;
389         } else if (period <= SPI_STATIC_PPR) {
390                 picosec = ppr_to_ps[period];
391         } else {
392                 picosec = period * 4000;
393         }
394
395         if (picosec == -1) {
396                 len = sprintf(buf, "reserved");
397         } else {
398                 len = sprint_frac(buf, picosec, 1000);
399         }
400
401         buf[len++] = '\n';
402         buf[len] = '\0';
403         return len;
404 }
405
406 static ssize_t
407 store_spi_transport_period_helper(struct class_device *cdev, const char *buf,
408                                   size_t count, int *periodp)
409 {
410         int j, picosec, period = -1;
411         char *endp;
412
413         picosec = simple_strtoul(buf, &endp, 10) * 1000;
414         if (*endp == '.') {
415                 int mult = 100;
416                 do {
417                         endp++;
418                         if (!isdigit(*endp))
419                                 break;
420                         picosec += (*endp - '0') * mult;
421                         mult /= 10;
422                 } while (mult > 0);
423         }
424
425         for (j = 0; j <= SPI_STATIC_PPR; j++) {
426                 if (ppr_to_ps[j] < picosec)
427                         continue;
428                 period = j;
429                 break;
430         }
431
432         if (period == -1)
433                 period = picosec / 4000;
434
435         if (period > 0xff)
436                 period = 0xff;
437
438         *periodp = period;
439
440         return count;
441 }
442
443 static ssize_t
444 show_spi_transport_period(struct class_device *cdev, char *buf)
445 {
446         struct scsi_target *starget = transport_class_to_starget(cdev);
447         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
448         struct spi_internal *i = to_spi_internal(shost->transportt);
449         struct spi_transport_attrs *tp =
450                 (struct spi_transport_attrs *)&starget->starget_data;
451
452         if (i->f->get_period)
453                 i->f->get_period(starget);
454
455         return show_spi_transport_period_helper(cdev, buf, tp->period);
456 }
457
458 static ssize_t
459 store_spi_transport_period(struct class_device *cdev, const char *buf,
460                             size_t count)
461 {
462         struct scsi_target *starget = transport_class_to_starget(cdev);
463         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
464         struct spi_internal *i = to_spi_internal(shost->transportt);
465         struct spi_transport_attrs *tp =
466                 (struct spi_transport_attrs *)&starget->starget_data;
467         int period, retval;
468
469         retval = store_spi_transport_period_helper(cdev, buf, count, &period);
470
471         if (period < tp->min_period)
472                 period = tp->min_period;
473
474         i->f->set_period(starget, period);
475
476         return retval;
477 }
478
479 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR, 
480                          show_spi_transport_period,
481                          store_spi_transport_period);
482
483 static ssize_t
484 show_spi_transport_min_period(struct class_device *cdev, char *buf)
485 {
486         struct scsi_target *starget = transport_class_to_starget(cdev);
487         struct spi_transport_attrs *tp =
488                 (struct spi_transport_attrs *)&starget->starget_data;
489
490         return show_spi_transport_period_helper(cdev, buf, tp->min_period);
491 }
492
493 static ssize_t
494 store_spi_transport_min_period(struct class_device *cdev, const char *buf,
495                             size_t count)
496 {
497         struct scsi_target *starget = transport_class_to_starget(cdev);
498         struct spi_transport_attrs *tp =
499                 (struct spi_transport_attrs *)&starget->starget_data;
500
501         return store_spi_transport_period_helper(cdev, buf, count,
502                                                  &tp->min_period);
503 }
504
505
506 static CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR, 
507                          show_spi_transport_min_period,
508                          store_spi_transport_min_period);
509
510
511 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
512 {
513         struct Scsi_Host *shost = transport_class_to_shost(cdev);
514         struct spi_internal *i = to_spi_internal(shost->transportt);
515
516         if (i->f->get_signalling)
517                 i->f->get_signalling(shost);
518
519         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
520 }
521 static ssize_t store_spi_host_signalling(struct class_device *cdev,
522                                          const char *buf, size_t count)
523 {
524         struct Scsi_Host *shost = transport_class_to_shost(cdev);
525         struct spi_internal *i = to_spi_internal(shost->transportt);
526         enum spi_signal_type type = spi_signal_to_value(buf);
527
528         if (type != SPI_SIGNAL_UNKNOWN)
529                 i->f->set_signalling(shost, type);
530
531         return count;
532 }
533 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
534                          show_spi_host_signalling,
535                          store_spi_host_signalling);
536
537 #define DV_SET(x, y)                    \
538         if(i->f->set_##x)               \
539                 i->f->set_##x(sdev->sdev_target, y)
540
541 enum spi_compare_returns {
542         SPI_COMPARE_SUCCESS,
543         SPI_COMPARE_FAILURE,
544         SPI_COMPARE_SKIP_TEST,
545 };
546
547
548 /* This is for read/write Domain Validation:  If the device supports
549  * an echo buffer, we do read/write tests to it */
550 static enum spi_compare_returns
551 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
552                           u8 *ptr, const int retries)
553 {
554         int len = ptr - buffer;
555         int j, k, r, result;
556         unsigned int pattern = 0x0000ffff;
557         struct scsi_sense_hdr sshdr;
558
559         const char spi_write_buffer[] = {
560                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
561         };
562         const char spi_read_buffer[] = {
563                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
564         };
565
566         /* set up the pattern buffer.  Doesn't matter if we spill
567          * slightly beyond since that's where the read buffer is */
568         for (j = 0; j < len; ) {
569
570                 /* fill the buffer with counting (test a) */
571                 for ( ; j < min(len, 32); j++)
572                         buffer[j] = j;
573                 k = j;
574                 /* fill the buffer with alternating words of 0x0 and
575                  * 0xffff (test b) */
576                 for ( ; j < min(len, k + 32); j += 2) {
577                         u16 *word = (u16 *)&buffer[j];
578                         
579                         *word = (j & 0x02) ? 0x0000 : 0xffff;
580                 }
581                 k = j;
582                 /* fill with crosstalk (alternating 0x5555 0xaaa)
583                  * (test c) */
584                 for ( ; j < min(len, k + 32); j += 2) {
585                         u16 *word = (u16 *)&buffer[j];
586
587                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
588                 }
589                 k = j;
590                 /* fill with shifting bits (test d) */
591                 for ( ; j < min(len, k + 32); j += 4) {
592                         u32 *word = (unsigned int *)&buffer[j];
593                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
594                         
595                         *word = pattern;
596                         pattern = (pattern << 1) | roll;
597                 }
598                 /* don't bother with random data (test e) */
599         }
600
601         for (r = 0; r < retries; r++) {
602                 result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
603                                      buffer, len, &sshdr);
604                 if(result || !scsi_device_online(sdev)) {
605
606                         scsi_device_set_state(sdev, SDEV_QUIESCE);
607                         if (scsi_sense_valid(&sshdr)
608                             && sshdr.sense_key == ILLEGAL_REQUEST
609                             /* INVALID FIELD IN CDB */
610                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
611                                 /* This would mean that the drive lied
612                                  * to us about supporting an echo
613                                  * buffer (unfortunately some Western
614                                  * Digital drives do precisely this)
615                                  */
616                                 return SPI_COMPARE_SKIP_TEST;
617
618
619                         sdev_printk(KERN_ERR, sdev, "Write Buffer failure %x\n", result);
620                         return SPI_COMPARE_FAILURE;
621                 }
622
623                 memset(ptr, 0, len);
624                 spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
625                             ptr, len, NULL);
626                 scsi_device_set_state(sdev, SDEV_QUIESCE);
627
628                 if (memcmp(buffer, ptr, len) != 0)
629                         return SPI_COMPARE_FAILURE;
630         }
631         return SPI_COMPARE_SUCCESS;
632 }
633
634 /* This is for the simplest form of Domain Validation: a read test
635  * on the inquiry data from the device */
636 static enum spi_compare_returns
637 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
638                               u8 *ptr, const int retries)
639 {
640         int r, result;
641         const int len = sdev->inquiry_len;
642         const char spi_inquiry[] = {
643                 INQUIRY, 0, 0, 0, len, 0
644         };
645
646         for (r = 0; r < retries; r++) {
647                 memset(ptr, 0, len);
648
649                 result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
650                                      ptr, len, NULL);
651                 
652                 if(result || !scsi_device_online(sdev)) {
653                         scsi_device_set_state(sdev, SDEV_QUIESCE);
654                         return SPI_COMPARE_FAILURE;
655                 }
656
657                 /* If we don't have the inquiry data already, the
658                  * first read gets it */
659                 if (ptr == buffer) {
660                         ptr += len;
661                         --r;
662                         continue;
663                 }
664
665                 if (memcmp(buffer, ptr, len) != 0)
666                         /* failure */
667                         return SPI_COMPARE_FAILURE;
668         }
669         return SPI_COMPARE_SUCCESS;
670 }
671
672 static enum spi_compare_returns
673 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
674                enum spi_compare_returns 
675                (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
676 {
677         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
678         struct scsi_target *starget = sdev->sdev_target;
679         int period = 0, prevperiod = 0; 
680         enum spi_compare_returns retval;
681
682
683         for (;;) {
684                 int newperiod;
685                 retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
686
687                 if (retval == SPI_COMPARE_SUCCESS
688                     || retval == SPI_COMPARE_SKIP_TEST)
689                         break;
690
691                 /* OK, retrain, fallback */
692                 if (i->f->get_iu)
693                         i->f->get_iu(starget);
694                 if (i->f->get_qas)
695                         i->f->get_qas(starget);
696                 if (i->f->get_period)
697                         i->f->get_period(sdev->sdev_target);
698
699                 /* Here's the fallback sequence; first try turning off
700                  * IU, then QAS (if we can control them), then finally
701                  * fall down the periods */
702                 if (i->f->set_iu && spi_iu(starget)) {
703                         starget_printk(KERN_ERR, starget, "Domain Validation Disabing Information Units\n");
704                         DV_SET(iu, 0);
705                 } else if (i->f->set_qas && spi_qas(starget)) {
706                         starget_printk(KERN_ERR, starget, "Domain Validation Disabing Quick Arbitration and Selection\n");
707                         DV_SET(qas, 0);
708                 } else {
709                         newperiod = spi_period(starget);
710                         period = newperiod > period ? newperiod : period;
711                         if (period < 0x0d)
712                                 period++;
713                         else
714                                 period += period >> 1;
715
716                         if (unlikely(period > 0xff || period == prevperiod)) {
717                                 /* Total failure; set to async and return */
718                                 starget_printk(KERN_ERR, starget, "Domain Validation Failure, dropping back to Asynchronous\n");
719                                 DV_SET(offset, 0);
720                                 return SPI_COMPARE_FAILURE;
721                         }
722                         starget_printk(KERN_ERR, starget, "Domain Validation detected failure, dropping back\n");
723                         DV_SET(period, period);
724                         prevperiod = period;
725                 }
726         }
727         return retval;
728 }
729
730 static int
731 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
732 {
733         int l, result;
734
735         /* first off do a test unit ready.  This can error out 
736          * because of reservations or some other reason.  If it
737          * fails, the device won't let us write to the echo buffer
738          * so just return failure */
739         
740         const char spi_test_unit_ready[] = {
741                 TEST_UNIT_READY, 0, 0, 0, 0, 0
742         };
743
744         const char spi_read_buffer_descriptor[] = {
745                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
746         };
747
748         
749         /* We send a set of three TURs to clear any outstanding 
750          * unit attention conditions if they exist (Otherwise the
751          * buffer tests won't be happy).  If the TUR still fails
752          * (reservation conflict, device not ready, etc) just
753          * skip the write tests */
754         for (l = 0; ; l++) {
755                 result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE, 
756                                      NULL, 0, NULL);
757
758                 if(result) {
759                         if(l >= 3)
760                                 return 0;
761                 } else {
762                         /* TUR succeeded */
763                         break;
764                 }
765         }
766
767         result = spi_execute(sdev, spi_read_buffer_descriptor, 
768                              DMA_FROM_DEVICE, buffer, 4, NULL);
769
770         if (result)
771                 /* Device has no echo buffer */
772                 return 0;
773
774         return buffer[3] + ((buffer[2] & 0x1f) << 8);
775 }
776
777 static void
778 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
779 {
780         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
781         struct scsi_target *starget = sdev->sdev_target;
782         int len = sdev->inquiry_len;
783         /* first set us up for narrow async */
784         DV_SET(offset, 0);
785         DV_SET(width, 0);
786         
787         if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
788             != SPI_COMPARE_SUCCESS) {
789                 starget_printk(KERN_ERR, starget, "Domain Validation Initial Inquiry Failed\n");
790                 /* FIXME: should probably offline the device here? */
791                 return;
792         }
793
794         /* test width */
795         if (i->f->set_width && spi_max_width(starget) &&
796             scsi_device_wide(sdev)) {
797                 i->f->set_width(starget, 1);
798
799                 if (spi_dv_device_compare_inquiry(sdev, buffer,
800                                                    buffer + len,
801                                                    DV_LOOPS)
802                     != SPI_COMPARE_SUCCESS) {
803                         starget_printk(KERN_ERR, starget, "Wide Transfers Fail\n");
804                         i->f->set_width(starget, 0);
805                 }
806         }
807
808         if (!i->f->set_period)
809                 return;
810
811         /* device can't handle synchronous */
812         if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
813                 return;
814
815         /* len == -1 is the signal that we need to ascertain the
816          * presence of an echo buffer before trying to use it.  len ==
817          * 0 means we don't have an echo buffer */
818         len = -1;
819
820  retry:
821
822         /* now set up to the maximum */
823         DV_SET(offset, spi_max_offset(starget));
824         DV_SET(period, spi_min_period(starget));
825         /* try QAS requests; this should be harmless to set if the
826          * target supports it */
827         if (scsi_device_qas(sdev))
828                 DV_SET(qas, 1);
829         /* Also try IU transfers */
830         if (scsi_device_ius(sdev))
831                 DV_SET(iu, 1);
832         if (spi_min_period(starget) < 9) {
833                 /* This u320 (or u640). Ignore the coupled parameters
834                  * like DT and IU, but set the optional ones */
835                 DV_SET(rd_strm, 1);
836                 DV_SET(wr_flow, 1);
837                 DV_SET(rti, 1);
838                 if (spi_min_period(starget) == 8)
839                         DV_SET(pcomp_en, 1);
840         }
841         /* Do the read only INQUIRY tests */
842         spi_dv_retrain(sdev, buffer, buffer + sdev->inquiry_len,
843                        spi_dv_device_compare_inquiry);
844         /* See if we actually managed to negotiate and sustain DT */
845         if (i->f->get_dt)
846                 i->f->get_dt(starget);
847
848         /* see if the device has an echo buffer.  If it does we can do
849          * the SPI pattern write tests.  Because of some broken
850          * devices, we *only* try this on a device that has actually
851          * negotiated DT */
852
853         if (len == -1 && spi_dt(starget))
854                 len = spi_dv_device_get_echo_buffer(sdev, buffer);
855
856         if (len <= 0) {
857                 starget_printk(KERN_INFO, starget, "Domain Validation skipping write tests\n");
858                 return;
859         }
860
861         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
862                 starget_printk(KERN_WARNING, starget, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
863                 len = SPI_MAX_ECHO_BUFFER_SIZE;
864         }
865
866         if (spi_dv_retrain(sdev, buffer, buffer + len,
867                            spi_dv_device_echo_buffer)
868             == SPI_COMPARE_SKIP_TEST) {
869                 /* OK, the stupid drive can't do a write echo buffer
870                  * test after all, fall back to the read tests */
871                 len = 0;
872                 goto retry;
873         }
874 }
875
876
877 /**     spi_dv_device - Do Domain Validation on the device
878  *      @sdev:          scsi device to validate
879  *
880  *      Performs the domain validation on the given device in the
881  *      current execution thread.  Since DV operations may sleep,
882  *      the current thread must have user context.  Also no SCSI
883  *      related locks that would deadlock I/O issued by the DV may
884  *      be held.
885  */
886 void
887 spi_dv_device(struct scsi_device *sdev)
888 {
889         struct scsi_target *starget = sdev->sdev_target;
890         u8 *buffer;
891         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
892
893         if (unlikely(scsi_device_get(sdev)))
894                 return;
895
896         buffer = kmalloc(len, GFP_KERNEL);
897
898         if (unlikely(!buffer))
899                 goto out_put;
900
901         memset(buffer, 0, len);
902
903         /* We need to verify that the actual device will quiesce; the
904          * later target quiesce is just a nice to have */
905         if (unlikely(scsi_device_quiesce(sdev)))
906                 goto out_free;
907
908         scsi_target_quiesce(starget);
909
910         spi_dv_pending(starget) = 1;
911         down(&spi_dv_sem(starget));
912
913         starget_printk(KERN_INFO, starget, "Beginning Domain Validation\n");
914
915         spi_dv_device_internal(sdev, buffer);
916
917         starget_printk(KERN_INFO, starget, "Ending Domain Validation\n");
918
919         up(&spi_dv_sem(starget));
920         spi_dv_pending(starget) = 0;
921
922         scsi_target_resume(starget);
923
924         spi_initial_dv(starget) = 1;
925
926  out_free:
927         kfree(buffer);
928  out_put:
929         scsi_device_put(sdev);
930 }
931 EXPORT_SYMBOL(spi_dv_device);
932
933 struct work_queue_wrapper {
934         struct work_struct      work;
935         struct scsi_device      *sdev;
936 };
937
938 static void
939 spi_dv_device_work_wrapper(void *data)
940 {
941         struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
942         struct scsi_device *sdev = wqw->sdev;
943
944         kfree(wqw);
945         spi_dv_device(sdev);
946         spi_dv_pending(sdev->sdev_target) = 0;
947         scsi_device_put(sdev);
948 }
949
950
951 /**
952  *      spi_schedule_dv_device - schedule domain validation to occur on the device
953  *      @sdev:  The device to validate
954  *
955  *      Identical to spi_dv_device() above, except that the DV will be
956  *      scheduled to occur in a workqueue later.  All memory allocations
957  *      are atomic, so may be called from any context including those holding
958  *      SCSI locks.
959  */
960 void
961 spi_schedule_dv_device(struct scsi_device *sdev)
962 {
963         struct work_queue_wrapper *wqw =
964                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
965
966         if (unlikely(!wqw))
967                 return;
968
969         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
970                 kfree(wqw);
971                 return;
972         }
973         /* Set pending early (dv_device doesn't check it, only sets it) */
974         spi_dv_pending(sdev->sdev_target) = 1;
975         if (unlikely(scsi_device_get(sdev))) {
976                 kfree(wqw);
977                 spi_dv_pending(sdev->sdev_target) = 0;
978                 return;
979         }
980
981         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
982         wqw->sdev = sdev;
983
984         schedule_work(&wqw->work);
985 }
986 EXPORT_SYMBOL(spi_schedule_dv_device);
987
988 /**
989  * spi_display_xfer_agreement - Print the current target transfer agreement
990  * @starget: The target for which to display the agreement
991  *
992  * Each SPI port is required to maintain a transfer agreement for each
993  * other port on the bus.  This function prints a one-line summary of
994  * the current agreement; more detailed information is available in sysfs.
995  */
996 void spi_display_xfer_agreement(struct scsi_target *starget)
997 {
998         struct spi_transport_attrs *tp;
999         tp = (struct spi_transport_attrs *)&starget->starget_data;
1000
1001         if (tp->offset > 0 && tp->period > 0) {
1002                 unsigned int picosec, kb100;
1003                 char *scsi = "FAST-?";
1004                 char tmp[8];
1005
1006                 if (tp->period <= SPI_STATIC_PPR) {
1007                         picosec = ppr_to_ps[tp->period];
1008                         switch (tp->period) {
1009                                 case  7: scsi = "FAST-320"; break;
1010                                 case  8: scsi = "FAST-160"; break;
1011                                 case  9: scsi = "FAST-80"; break;
1012                                 case 10:
1013                                 case 11: scsi = "FAST-40"; break;
1014                                 case 12: scsi = "FAST-20"; break;
1015                         }
1016                 } else {
1017                         picosec = tp->period * 4000;
1018                         if (tp->period < 25)
1019                                 scsi = "FAST-20";
1020                         else if (tp->period < 50)
1021                                 scsi = "FAST-10";
1022                         else
1023                                 scsi = "FAST-5";
1024                 }
1025
1026                 kb100 = (10000000 + picosec / 2) / picosec;
1027                 if (tp->width)
1028                         kb100 *= 2;
1029                 sprint_frac(tmp, picosec, 1000);
1030
1031                 dev_info(&starget->dev,
1032                          "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1033                          scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1034                          tp->dt ? "DT" : "ST",
1035                          tp->iu ? " IU" : "",
1036                          tp->qas  ? " QAS" : "",
1037                          tp->rd_strm ? " RDSTRM" : "",
1038                          tp->rti ? " RTI" : "",
1039                          tp->wr_flow ? " WRFLOW" : "",
1040                          tp->pcomp_en ? " PCOMP" : "",
1041                          tp->hold_mcs ? " HMCS" : "",
1042                          tmp, tp->offset);
1043         } else {
1044                 dev_info(&starget->dev, "%sasynchronous\n",
1045                                 tp->width ? "wide " : "");
1046         }
1047 }
1048 EXPORT_SYMBOL(spi_display_xfer_agreement);
1049
1050 #define SETUP_ATTRIBUTE(field)                                          \
1051         i->private_attrs[count] = class_device_attr_##field;            \
1052         if (!i->f->set_##field) {                                       \
1053                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1054                 i->private_attrs[count].store = NULL;                   \
1055         }                                                               \
1056         i->attrs[count] = &i->private_attrs[count];                     \
1057         if (i->f->show_##field)                                         \
1058                 count++
1059
1060 #define SETUP_RELATED_ATTRIBUTE(field, rel_field)                       \
1061         i->private_attrs[count] = class_device_attr_##field;            \
1062         if (!i->f->set_##rel_field) {                                   \
1063                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1064                 i->private_attrs[count].store = NULL;                   \
1065         }                                                               \
1066         i->attrs[count] = &i->private_attrs[count];                     \
1067         if (i->f->show_##rel_field)                                     \
1068                 count++
1069
1070 #define SETUP_HOST_ATTRIBUTE(field)                                     \
1071         i->private_host_attrs[count] = class_device_attr_##field;       \
1072         if (!i->f->set_##field) {                                       \
1073                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
1074                 i->private_host_attrs[count].store = NULL;              \
1075         }                                                               \
1076         i->host_attrs[count] = &i->private_host_attrs[count];           \
1077         count++
1078
1079 static int spi_device_match(struct attribute_container *cont,
1080                             struct device *dev)
1081 {
1082         struct scsi_device *sdev;
1083         struct Scsi_Host *shost;
1084         struct spi_internal *i;
1085
1086         if (!scsi_is_sdev_device(dev))
1087                 return 0;
1088
1089         sdev = to_scsi_device(dev);
1090         shost = sdev->host;
1091         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1092             != &spi_host_class.class)
1093                 return 0;
1094         /* Note: this class has no device attributes, so it has
1095          * no per-HBA allocation and thus we don't need to distinguish
1096          * the attribute containers for the device */
1097         i = to_spi_internal(shost->transportt);
1098         if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1099                 return 0;
1100         return 1;
1101 }
1102
1103 static int spi_target_match(struct attribute_container *cont,
1104                             struct device *dev)
1105 {
1106         struct Scsi_Host *shost;
1107         struct scsi_target *starget;
1108         struct spi_internal *i;
1109
1110         if (!scsi_is_target_device(dev))
1111                 return 0;
1112
1113         shost = dev_to_shost(dev->parent);
1114         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1115             != &spi_host_class.class)
1116                 return 0;
1117
1118         i = to_spi_internal(shost->transportt);
1119         starget = to_scsi_target(dev);
1120
1121         if (i->f->deny_binding && i->f->deny_binding(starget))
1122                 return 0;
1123
1124         return &i->t.target_attrs.ac == cont;
1125 }
1126
1127 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1128                                "spi_transport",
1129                                spi_setup_transport_attrs,
1130                                NULL,
1131                                NULL);
1132
1133 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1134                                     spi_device_match,
1135                                     spi_device_configure);
1136
1137 struct scsi_transport_template *
1138 spi_attach_transport(struct spi_function_template *ft)
1139 {
1140         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
1141                                          GFP_KERNEL);
1142         int count = 0;
1143         if (unlikely(!i))
1144                 return NULL;
1145
1146         memset(i, 0, sizeof(struct spi_internal));
1147
1148
1149         i->t.target_attrs.ac.class = &spi_transport_class.class;
1150         i->t.target_attrs.ac.attrs = &i->attrs[0];
1151         i->t.target_attrs.ac.match = spi_target_match;
1152         transport_container_register(&i->t.target_attrs);
1153         i->t.target_size = sizeof(struct spi_transport_attrs);
1154         i->t.host_attrs.ac.class = &spi_host_class.class;
1155         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
1156         i->t.host_attrs.ac.match = spi_host_match;
1157         transport_container_register(&i->t.host_attrs);
1158         i->t.host_size = sizeof(struct spi_host_attrs);
1159         i->f = ft;
1160
1161         SETUP_ATTRIBUTE(period);
1162         SETUP_RELATED_ATTRIBUTE(min_period, period);
1163         SETUP_ATTRIBUTE(offset);
1164         SETUP_RELATED_ATTRIBUTE(max_offset, offset);
1165         SETUP_ATTRIBUTE(width);
1166         SETUP_RELATED_ATTRIBUTE(max_width, width);
1167         SETUP_ATTRIBUTE(iu);
1168         SETUP_ATTRIBUTE(dt);
1169         SETUP_ATTRIBUTE(qas);
1170         SETUP_ATTRIBUTE(wr_flow);
1171         SETUP_ATTRIBUTE(rd_strm);
1172         SETUP_ATTRIBUTE(rti);
1173         SETUP_ATTRIBUTE(pcomp_en);
1174         SETUP_ATTRIBUTE(hold_mcs);
1175
1176         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
1177          * this bug will trigger */
1178         BUG_ON(count > SPI_NUM_ATTRS);
1179
1180         i->attrs[count++] = &class_device_attr_revalidate;
1181
1182         i->attrs[count] = NULL;
1183
1184         count = 0;
1185         SETUP_HOST_ATTRIBUTE(signalling);
1186
1187         BUG_ON(count > SPI_HOST_ATTRS);
1188
1189         i->host_attrs[count] = NULL;
1190
1191         return &i->t;
1192 }
1193 EXPORT_SYMBOL(spi_attach_transport);
1194
1195 void spi_release_transport(struct scsi_transport_template *t)
1196 {
1197         struct spi_internal *i = to_spi_internal(t);
1198
1199         transport_container_unregister(&i->t.target_attrs);
1200         transport_container_unregister(&i->t.host_attrs);
1201
1202         kfree(i);
1203 }
1204 EXPORT_SYMBOL(spi_release_transport);
1205
1206 static __init int spi_transport_init(void)
1207 {
1208         int error = transport_class_register(&spi_transport_class);
1209         if (error)
1210                 return error;
1211         error = anon_transport_class_register(&spi_device_class);
1212         return transport_class_register(&spi_host_class);
1213 }
1214
1215 static void __exit spi_transport_exit(void)
1216 {
1217         transport_class_unregister(&spi_transport_class);
1218         anon_transport_class_unregister(&spi_device_class);
1219         transport_class_unregister(&spi_host_class);
1220 }
1221
1222 MODULE_AUTHOR("Martin Hicks");
1223 MODULE_DESCRIPTION("SPI Transport Attributes");
1224 MODULE_LICENSE("GPL");
1225
1226 module_init(spi_transport_init);
1227 module_exit(spi_transport_exit);