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