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