git.oblomov.eu Git - linux-2.6/blob - 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);