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