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_request.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 void spi_wait_req(struct scsi_request *sreq, const void *cmd,
 112                          void *buffer, unsigned bufflen)
 113 {
 114         int i;
 115
 116         for(i = 0; i < DV_RETRIES; i++) {
 117                 sreq->sr_request->flags |= REQ_FAILFAST;
 118
 119                 scsi_wait_req(sreq, cmd, buffer, bufflen,
 120                               DV_TIMEOUT, /* retries */ 1);
 121                 if (sreq->sr_result & DRIVER_SENSE) {
 122                         struct scsi_sense_hdr sshdr;
 123
 124                         if (scsi_request_normalize_sense(sreq, &sshdr)
 125                             && sshdr.sense_key == UNIT_ATTENTION)
 126                                 continue;
 127                 }
 128                 break;
 129         }
 130 }
 131
 132 static struct {
 133         enum spi_signal_type    value;
 134         char                    *name;
 135 } signal_types[] = {
 136         { SPI_SIGNAL_UNKNOWN, "unknown" },
 137         { SPI_SIGNAL_SE, "SE" },
 138         { SPI_SIGNAL_LVD, "LVD" },
 139         { SPI_SIGNAL_HVD, "HVD" },
 140 };
 141
 142 static inline const char *spi_signal_to_string(enum spi_signal_type type)
 143 {
 144         int i;
 145
 146         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 147                 if (type == signal_types[i].value)
 148                         return signal_types[i].name;
 149         }
 150         return NULL;
 151 }
 152 static inline enum spi_signal_type spi_signal_to_value(const char *name)
 153 {
 154         int i, len;
 155
 156         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 157                 len =  strlen(signal_types[i].name);
 158                 if (strncmp(name, signal_types[i].name, len) == 0 &&
 159                     (name[len] == '\n' || name[len] == '\0'))
 160                         return signal_types[i].value;
 161         }
 162         return SPI_SIGNAL_UNKNOWN;
 163 }
 164
 165 static int spi_host_setup(struct device *dev)
 166 {
 167         struct Scsi_Host *shost = dev_to_shost(dev);
 168
 169         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
 170
 171         return 0;
 172 }
 173
 174 static DECLARE_TRANSPORT_CLASS(spi_host_class,
 175                                "spi_host",
 176                                spi_host_setup,
 177                                NULL,
 178                                NULL);
 179
 180 static int spi_host_match(struct attribute_container *cont,
 181                           struct device *dev)
 182 {
 183         struct Scsi_Host *shost;
 184         struct spi_internal *i;
 185
 186         if (!scsi_is_host_device(dev))
 187                 return 0;
 188
 189         shost = dev_to_shost(dev);
 190         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
 191             != &spi_host_class.class)
 192                 return 0;
 193
 194         i = to_spi_internal(shost->transportt);
 195
 196         return &i->t.host_attrs.ac == cont;
 197 }
 198
 199 static int spi_device_configure(struct device *dev)
 200 {
 201         struct scsi_device *sdev = to_scsi_device(dev);
 202         struct scsi_target *starget = sdev->sdev_target;
 203
 204         /* Populate the target capability fields with the values
 205          * gleaned from the device inquiry */
 206
 207         spi_support_sync(starget) = scsi_device_sync(sdev);
 208         spi_support_wide(starget) = scsi_device_wide(sdev);
 209         spi_support_dt(starget) = scsi_device_dt(sdev);
 210         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
 211         spi_support_ius(starget) = scsi_device_ius(sdev);
 212         spi_support_qas(starget) = scsi_device_qas(sdev);
 213
 214         return 0;
 215 }
 216
 217 static int spi_setup_transport_attrs(struct device *dev)
 218 {
 219         struct scsi_target *starget = to_scsi_target(dev);
 220
 221         spi_period(starget) = -1;       /* illegal value */
 222         spi_min_period(starget) = 0;
 223         spi_offset(starget) = 0;        /* async */
 224         spi_max_offset(starget) = 255;
 225         spi_width(starget) = 0; /* narrow */
 226         spi_max_width(starget) = 1;
 227         spi_iu(starget) = 0;    /* no IU */
 228         spi_dt(starget) = 0;    /* ST */
 229         spi_qas(starget) = 0;
 230         spi_wr_flow(starget) = 0;
 231         spi_rd_strm(starget) = 0;
 232         spi_rti(starget) = 0;
 233         spi_pcomp_en(starget) = 0;
 234         spi_hold_mcs(starget) = 0;
 235         spi_dv_pending(starget) = 0;
 236         spi_initial_dv(starget) = 0;
 237         init_MUTEX(&spi_dv_sem(starget));
 238
 239         return 0;
 240 }
 241
 242 #define spi_transport_show_simple(field, format_string)                 \
 243                                                                         \
 244 static ssize_t                                                          \
 245 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
 246 {                                                                       \
 247         struct scsi_target *starget = transport_class_to_starget(cdev); \
 248         struct spi_transport_attrs *tp;                                 \
 249                                                                         \
 250         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
 251         return snprintf(buf, 20, format_string, tp->field);             \
 252 }
 253
 254 #define spi_transport_store_simple(field, format_string)                \
 255                                                                         \
 256 static ssize_t                                                          \
 257 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
 258                             size_t count)                               \
 259 {                                                                       \
 260         int val;                                                        \
 261         struct scsi_target *starget = transport_class_to_starget(cdev); \
 262         struct spi_transport_attrs *tp;                                 \
 263                                                                         \
 264         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
 265         val = simple_strtoul(buf, NULL, 0);                             \
 266         tp->field = val;                                                \
 267         return count;                                                   \
 268 }
 269
 270 #define spi_transport_show_function(field, format_string)               \
 271                                                                         \
 272 static ssize_t                                                          \
 273 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
 274 {                                                                       \
 275         struct scsi_target *starget = transport_class_to_starget(cdev); \
 276         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 277         struct spi_transport_attrs *tp;                                 \
 278         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 279         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
 280         if (i->f->get_##field)                                          \
 281                 i->f->get_##field(starget);                             \
 282         return snprintf(buf, 20, format_string, tp->field);             \
 283 }
 284
 285 #define spi_transport_store_function(field, format_string)              \
 286 static ssize_t                                                          \
 287 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
 288                             size_t count)                               \
 289 {                                                                       \
 290         int val;                                                        \
 291         struct scsi_target *starget = transport_class_to_starget(cdev); \
 292         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 293         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 294                                                                         \
 295         val = simple_strtoul(buf, NULL, 0);                             \
 296         i->f->set_##field(starget, val);                        \
 297         return count;                                                   \
 298 }
 299
 300 #define spi_transport_store_max(field, format_string)                   \
 301 static ssize_t                                                          \
 302 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
 303                             size_t count)                               \
 304 {                                                                       \
 305         int val;                                                        \
 306         struct scsi_target *starget = transport_class_to_starget(cdev); \
 307         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 308         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 309         struct spi_transport_attrs *tp                                  \
 310                 = (struct spi_transport_attrs *)&starget->starget_data; \
 311                                                                         \
 312         val = simple_strtoul(buf, NULL, 0);                             \
 313         if (val > tp->max_##field)                                      \
 314                 val = tp->max_##field;                                  \
 315         i->f->set_##field(starget, val);                                \
 316         return count;                                                   \
 317 }
 318
 319 #define spi_transport_rd_attr(field, format_string)                     \
 320         spi_transport_show_function(field, format_string)               \
 321         spi_transport_store_function(field, format_string)              \
 322 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
 323                          show_spi_transport_##field,                    \
 324                          store_spi_transport_##field);
 325
 326 #define spi_transport_simple_attr(field, format_string)                 \
 327         spi_transport_show_simple(field, format_string)                 \
 328         spi_transport_store_simple(field, format_string)                \
 329 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
 330                          show_spi_transport_##field,                    \
 331                          store_spi_transport_##field);
 332
 333 #define spi_transport_max_attr(field, format_string)                    \
 334         spi_transport_show_function(field, format_string)               \
 335         spi_transport_store_max(field, format_string)                   \
 336         spi_transport_simple_attr(max_##field, format_string)           \
 337 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
 338                          show_spi_transport_##field,                    \
 339                          store_spi_transport_##field);
 340
 341 /* The Parallel SCSI Tranport Attributes: */
 342 spi_transport_max_attr(offset, "%d\n");
 343 spi_transport_max_attr(width, "%d\n");
 344 spi_transport_rd_attr(iu, "%d\n");
 345 spi_transport_rd_attr(dt, "%d\n");
 346 spi_transport_rd_attr(qas, "%d\n");
 347 spi_transport_rd_attr(wr_flow, "%d\n");
 348 spi_transport_rd_attr(rd_strm, "%d\n");
 349 spi_transport_rd_attr(rti, "%d\n");
 350 spi_transport_rd_attr(pcomp_en, "%d\n");
 351 spi_transport_rd_attr(hold_mcs, "%d\n");
 352
 353 /* we only care about the first child device so we return 1 */
 354 static int child_iter(struct device *dev, void *data)
 355 {
 356         struct scsi_device *sdev = to_scsi_device(dev);
 357
 358         spi_dv_device(sdev);
 359         return 1;
 360 }
 361
 362 static ssize_t
 363 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
 364 {
 365         struct scsi_target *starget = transport_class_to_starget(cdev);
 366
 367         device_for_each_child(&starget->dev, NULL, child_iter);
 368         return count;
 369 }
 370 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
 371
 372 /* Translate the period into ns according to the current spec
 373  * for SDTR/PPR messages */
 374 static ssize_t
 375 show_spi_transport_period_helper(struct class_device *cdev, char *buf,
 376                                  int period)
 377 {
 378         int len, picosec;
 379
 380         if (period < 0 || period > 0xff) {
 381                 picosec = -1;
 382         } else if (period <= SPI_STATIC_PPR) {
 383                 picosec = ppr_to_ps[period];
 384         } else {
 385                 picosec = period * 4000;
 386         }
 387
 388         if (picosec == -1) {
 389                 len = sprintf(buf, "reserved");
 390         } else {
 391                 len = sprint_frac(buf, picosec, 1000);
 392         }
 393
 394         buf[len++] = '\n';
 395         buf[len] = '\0';
 396         return len;
 397 }
 398
 399 static ssize_t
 400 store_spi_transport_period_helper(struct class_device *cdev, const char *buf,
 401                                   size_t count, int *periodp)
 402 {
 403         int j, picosec, period = -1;
 404         char *endp;
 405
 406         picosec = simple_strtoul(buf, &endp, 10) * 1000;
 407         if (*endp == '.') {
 408                 int mult = 100;
 409                 do {
 410                         endp++;
 411                         if (!isdigit(*endp))
 412                                 break;
 413                         picosec += (*endp - '0') * mult;
 414                         mult /= 10;
 415                 } while (mult > 0);
 416         }
 417
 418         for (j = 0; j <= SPI_STATIC_PPR; j++) {
 419                 if (ppr_to_ps[j] < picosec)
 420                         continue;
 421                 period = j;
 422                 break;
 423         }
 424
 425         if (period == -1)
 426                 period = picosec / 4000;
 427
 428         if (period > 0xff)
 429                 period = 0xff;
 430
 431         *periodp = period;
 432
 433         return count;
 434 }
 435
 436 static ssize_t
 437 show_spi_transport_period(struct class_device *cdev, char *buf)
 438 {
 439         struct scsi_target *starget = transport_class_to_starget(cdev);
 440         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 441         struct spi_internal *i = to_spi_internal(shost->transportt);
 442         struct spi_transport_attrs *tp =
 443                 (struct spi_transport_attrs *)&starget->starget_data;
 444
 445         if (i->f->get_period)
 446                 i->f->get_period(starget);
 447
 448         return show_spi_transport_period_helper(cdev, buf, tp->period);
 449 }
 450
 451 static ssize_t
 452 store_spi_transport_period(struct class_device *cdev, const char *buf,
 453                             size_t count)
 454 {
 455         struct scsi_target *starget = transport_class_to_starget(cdev);
 456         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 457         struct spi_internal *i = to_spi_internal(shost->transportt);
 458         struct spi_transport_attrs *tp =
 459                 (struct spi_transport_attrs *)&starget->starget_data;
 460         int period, retval;
 461
 462         retval = store_spi_transport_period_helper(cdev, buf, count, &period);
 463
 464         if (period < tp->min_period)
 465                 period = tp->min_period;
 466
 467         i->f->set_period(starget, period);
 468
 469         return retval;
 470 }
 471
 472 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
 473                          show_spi_transport_period,
 474                          store_spi_transport_period);
 475
 476 static ssize_t
 477 show_spi_transport_min_period(struct class_device *cdev, char *buf)
 478 {
 479         struct scsi_target *starget = transport_class_to_starget(cdev);
 480         struct spi_transport_attrs *tp =
 481                 (struct spi_transport_attrs *)&starget->starget_data;
 482
 483         return show_spi_transport_period_helper(cdev, buf, tp->min_period);
 484 }
 485
 486 static ssize_t
 487 store_spi_transport_min_period(struct class_device *cdev, const char *buf,
 488                             size_t count)
 489 {
 490         struct scsi_target *starget = transport_class_to_starget(cdev);
 491         struct spi_transport_attrs *tp =
 492                 (struct spi_transport_attrs *)&starget->starget_data;
 493
 494         return store_spi_transport_period_helper(cdev, buf, count,
 495                                                  &tp->min_period);
 496 }
 497
 498
 499 static CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR,
 500                          show_spi_transport_min_period,
 501                          store_spi_transport_min_period);
 502
 503
 504 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
 505 {
 506         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 507         struct spi_internal *i = to_spi_internal(shost->transportt);
 508
 509         if (i->f->get_signalling)
 510                 i->f->get_signalling(shost);
 511
 512         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
 513 }
 514 static ssize_t store_spi_host_signalling(struct class_device *cdev,
 515                                          const char *buf, size_t count)
 516 {
 517         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 518         struct spi_internal *i = to_spi_internal(shost->transportt);
 519         enum spi_signal_type type = spi_signal_to_value(buf);
 520
 521         if (type != SPI_SIGNAL_UNKNOWN)
 522                 i->f->set_signalling(shost, type);
 523
 524         return count;
 525 }
 526 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
 527                          show_spi_host_signalling,
 528                          store_spi_host_signalling);
 529
 530 #define DV_SET(x, y)                    \
 531         if(i->f->set_##x)               \
 532                 i->f->set_##x(sdev->sdev_target, y)
 533
 534 enum spi_compare_returns {
 535         SPI_COMPARE_SUCCESS,
 536         SPI_COMPARE_FAILURE,
 537         SPI_COMPARE_SKIP_TEST,
 538 };
 539
 540
 541 /* This is for read/write Domain Validation:  If the device supports
 542  * an echo buffer, we do read/write tests to it */
 543 static enum spi_compare_returns
 544 spi_dv_device_echo_buffer(struct scsi_request *sreq, u8 *buffer,
 545                           u8 *ptr, const int retries)
 546 {
 547         struct scsi_device *sdev = sreq->sr_device;
 548         int len = ptr - buffer;
 549         int j, k, r;
 550         unsigned int pattern = 0x0000ffff;
 551
 552         const char spi_write_buffer[] = {
 553                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 554         };
 555         const char spi_read_buffer[] = {
 556                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 557         };
 558
 559         /* set up the pattern buffer.  Doesn't matter if we spill
 560          * slightly beyond since that's where the read buffer is */
 561         for (j = 0; j < len; ) {
 562
 563                 /* fill the buffer with counting (test a) */
 564                 for ( ; j < min(len, 32); j++)
 565                         buffer[j] = j;
 566                 k = j;
 567                 /* fill the buffer with alternating words of 0x0 and
 568                  * 0xffff (test b) */
 569                 for ( ; j < min(len, k + 32); j += 2) {
 570                         u16 *word = (u16 *)&buffer[j];
 571
 572                         *word = (j & 0x02) ? 0x0000 : 0xffff;
 573                 }
 574                 k = j;
 575                 /* fill with crosstalk (alternating 0x5555 0xaaa)
 576                  * (test c) */
 577                 for ( ; j < min(len, k + 32); j += 2) {
 578                         u16 *word = (u16 *)&buffer[j];
 579
 580                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
 581                 }
 582                 k = j;
 583                 /* fill with shifting bits (test d) */
 584                 for ( ; j < min(len, k + 32); j += 4) {
 585                         u32 *word = (unsigned int *)&buffer[j];
 586                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
 587
 588                         *word = pattern;
 589                         pattern = (pattern << 1) | roll;
 590                 }
 591                 /* don't bother with random data (test e) */
 592         }
 593
 594         for (r = 0; r < retries; r++) {
 595                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 596                 sreq->sr_data_direction = DMA_TO_DEVICE;
 597                 spi_wait_req(sreq, spi_write_buffer, buffer, len);
 598                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 599                         struct scsi_sense_hdr sshdr;
 600
 601                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 602                         if (scsi_request_normalize_sense(sreq, &sshdr)
 603                             && sshdr.sense_key == ILLEGAL_REQUEST
 604                             /* INVALID FIELD IN CDB */
 605                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
 606                                 /* This would mean that the drive lied
 607                                  * to us about supporting an echo
 608                                  * buffer (unfortunately some Western
 609                                  * Digital drives do precisely this)
 610                                  */
 611                                 return SPI_COMPARE_SKIP_TEST;
 612
 613
 614                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Write Buffer failure %x\n", sreq->sr_result);
 615                         return SPI_COMPARE_FAILURE;
 616                 }
 617
 618                 memset(ptr, 0, len);
 619                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 620                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 621                 spi_wait_req(sreq, spi_read_buffer, ptr, len);
 622                 scsi_device_set_state(sdev, SDEV_QUIESCE);
 623
 624                 if (memcmp(buffer, ptr, len) != 0)
 625                         return SPI_COMPARE_FAILURE;
 626         }
 627         return SPI_COMPARE_SUCCESS;
 628 }
 629
 630 /* This is for the simplest form of Domain Validation: a read test
 631  * on the inquiry data from the device */
 632 static enum spi_compare_returns
 633 spi_dv_device_compare_inquiry(struct scsi_request *sreq, u8 *buffer,
 634                               u8 *ptr, const int retries)
 635 {
 636         int r;
 637         const int len = sreq->sr_device->inquiry_len;
 638         struct scsi_device *sdev = sreq->sr_device;
 639         const char spi_inquiry[] = {
 640                 INQUIRY, 0, 0, 0, len, 0
 641         };
 642
 643         for (r = 0; r < retries; r++) {
 644                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 645                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 646
 647                 memset(ptr, 0, len);
 648
 649                 spi_wait_req(sreq, spi_inquiry, ptr, len);
 650
 651                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 652                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 653                         return SPI_COMPARE_FAILURE;
 654                 }
 655
 656                 /* If we don't have the inquiry data already, the
 657                  * first read gets it */
 658                 if (ptr == buffer) {
 659                         ptr += len;
 660                         --r;
 661                         continue;
 662                 }
 663
 664                 if (memcmp(buffer, ptr, len) != 0)
 665                         /* failure */
 666                         return SPI_COMPARE_FAILURE;
 667         }
 668         return SPI_COMPARE_SUCCESS;
 669 }
 670
 671 static enum spi_compare_returns
 672 spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
 673                enum spi_compare_returns
 674                (*compare_fn)(struct scsi_request *, u8 *, u8 *, int))
 675 {
 676         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 677         struct scsi_device *sdev = sreq->sr_device;
 678         struct scsi_target *starget = sdev->sdev_target;
 679         int period = 0, prevperiod = 0;
 680         enum spi_compare_returns retval;
 681
 682
 683         for (;;) {
 684                 int newperiod;
 685                 retval = compare_fn(sreq, buffer, ptr, DV_LOOPS);
 686
 687                 if (retval == SPI_COMPARE_SUCCESS
 688                     || retval == SPI_COMPARE_SKIP_TEST)
 689                         break;
 690
 691                 /* OK, retrain, fallback */
 692                 if (i->f->get_iu)
 693                         i->f->get_iu(starget);
 694                 if (i->f->get_qas)
 695                         i->f->get_qas(starget);
 696                 if (i->f->get_period)
 697                         i->f->get_period(sdev->sdev_target);
 698
 699                 /* Here's the fallback sequence; first try turning off
 700                  * IU, then QAS (if we can control them), then finally
 701                  * fall down the periods */
 702                 if (i->f->set_iu && spi_iu(starget)) {
 703                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Information Units\n");
 704                         DV_SET(iu, 0);
 705                 } else if (i->f->set_qas && spi_qas(starget)) {
 706                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Quick Arbitration and Selection\n");
 707                         DV_SET(qas, 0);
 708                 } else {
 709                         newperiod = spi_period(starget);
 710                         period = newperiod > period ? newperiod : period;
 711                         if (period < 0x0d)
 712                                 period++;
 713                         else
 714                                 period += period >> 1;
 715
 716                         if (unlikely(period > 0xff || period == prevperiod)) {
 717                                 /* Total failure; set to async and return */
 718                                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
 719                                 DV_SET(offset, 0);
 720                                 return SPI_COMPARE_FAILURE;
 721                         }
 722                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation detected failure, dropping back\n");
 723                         DV_SET(period, period);
 724                         prevperiod = period;
 725                 }
 726         }
 727         return retval;
 728 }
 729
 730 static int
 731 spi_dv_device_get_echo_buffer(struct scsi_request *sreq, u8 *buffer)
 732 {
 733         int l;
 734
 735         /* first off do a test unit ready.  This can error out
 736          * because of reservations or some other reason.  If it
 737          * fails, the device won't let us write to the echo buffer
 738          * so just return failure */
 739
 740         const char spi_test_unit_ready[] = {
 741                 TEST_UNIT_READY, 0, 0, 0, 0, 0
 742         };
 743
 744         const char spi_read_buffer_descriptor[] = {
 745                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
 746         };
 747
 748
 749         sreq->sr_cmd_len = 0;
 750         sreq->sr_data_direction = DMA_NONE;
 751
 752         /* We send a set of three TURs to clear any outstanding
 753          * unit attention conditions if they exist (Otherwise the
 754          * buffer tests won't be happy).  If the TUR still fails
 755          * (reservation conflict, device not ready, etc) just
 756          * skip the write tests */
 757         for (l = 0; ; l++) {
 758                 spi_wait_req(sreq, spi_test_unit_ready, NULL, 0);
 759
 760                 if(sreq->sr_result) {
 761                         if(l >= 3)
 762                                 return 0;
 763                 } else {
 764                         /* TUR succeeded */
 765                         break;
 766                 }
 767         }
 768
 769         sreq->sr_cmd_len = 0;
 770         sreq->sr_data_direction = DMA_FROM_DEVICE;
 771
 772         spi_wait_req(sreq, spi_read_buffer_descriptor, buffer, 4);
 773
 774         if (sreq->sr_result)
 775                 /* Device has no echo buffer */
 776                 return 0;
 777
 778         return buffer[3] + ((buffer[2] & 0x1f) << 8);
 779 }
 780
 781 static void
 782 spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
 783 {
 784         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 785         struct scsi_device *sdev = sreq->sr_device;
 786         struct scsi_target *starget = sdev->sdev_target;
 787         int len = sdev->inquiry_len;
 788         /* first set us up for narrow async */
 789         DV_SET(offset, 0);
 790         DV_SET(width, 0);
 791
 792         if (spi_dv_device_compare_inquiry(sreq, buffer, buffer, DV_LOOPS)
 793             != SPI_COMPARE_SUCCESS) {
 794                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
 795                 /* FIXME: should probably offline the device here? */
 796                 return;
 797         }
 798
 799         /* test width */
 800         if (i->f->set_width && spi_max_width(starget) &&
 801             scsi_device_wide(sdev)) {
 802                 i->f->set_width(starget, 1);
 803
 804                 if (spi_dv_device_compare_inquiry(sreq, buffer,
 805                                                    buffer + len,
 806                                                    DV_LOOPS)
 807                     != SPI_COMPARE_SUCCESS) {
 808                         SPI_PRINTK(starget, KERN_ERR, "Wide Transfers Fail\n");
 809                         i->f->set_width(starget, 0);
 810                 }
 811         }
 812
 813         if (!i->f->set_period)
 814                 return;
 815
 816         /* device can't handle synchronous */
 817         if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
 818                 return;
 819
 820         /* see if the device has an echo buffer.  If it does we can
 821          * do the SPI pattern write tests */
 822
 823         len = 0;
 824         if (scsi_device_dt(sdev))
 825                 len = spi_dv_device_get_echo_buffer(sreq, buffer);
 826
 827  retry:
 828
 829         /* now set up to the maximum */
 830         DV_SET(offset, spi_max_offset(starget));
 831         DV_SET(period, spi_min_period(starget));
 832         /* try QAS requests; this should be harmless to set if the
 833          * target supports it */
 834         if (scsi_device_qas(sdev))
 835                 DV_SET(qas, 1);
 836         /* Also try IU transfers */
 837         if (scsi_device_ius(sdev))
 838                 DV_SET(iu, 1);
 839         if (spi_min_period(starget) < 9) {
 840                 /* This u320 (or u640). Ignore the coupled parameters
 841                  * like DT and IU, but set the optional ones */
 842                 DV_SET(rd_strm, 1);
 843                 DV_SET(wr_flow, 1);
 844                 DV_SET(rti, 1);
 845                 if (spi_min_period(starget) == 8)
 846                         DV_SET(pcomp_en, 1);
 847         }
 848
 849         if (len == 0) {
 850                 SPI_PRINTK(starget, KERN_INFO, "Domain Validation skipping write tests\n");
 851                 spi_dv_retrain(sreq, buffer, buffer + len,
 852                                spi_dv_device_compare_inquiry);
 853                 return;
 854         }
 855
 856         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
 857                 SPI_PRINTK(starget, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
 858                 len = SPI_MAX_ECHO_BUFFER_SIZE;
 859         }
 860
 861         if (spi_dv_retrain(sreq, buffer, buffer + len,
 862                            spi_dv_device_echo_buffer)
 863             == SPI_COMPARE_SKIP_TEST) {
 864                 /* OK, the stupid drive can't do a write echo buffer
 865                  * test after all, fall back to the read tests */
 866                 len = 0;
 867                 goto retry;
 868         }
 869 }
 870
 871
 872 /**     spi_dv_device - Do Domain Validation on the device
 873  *      @sdev:          scsi device to validate
 874  *
 875  *      Performs the domain validation on the given device in the
 876  *      current execution thread.  Since DV operations may sleep,
 877  *      the current thread must have user context.  Also no SCSI
 878  *      related locks that would deadlock I/O issued by the DV may
 879  *      be held.
 880  */
 881 void
 882 spi_dv_device(struct scsi_device *sdev)
 883 {
 884         struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL);
 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(!sreq))
 890                 return;
 891
 892         if (unlikely(scsi_device_get(sdev)))
 893                 goto out_free_req;
 894
 895         buffer = kmalloc(len, GFP_KERNEL);
 896
 897         if (unlikely(!buffer))
 898                 goto out_put;
 899
 900         memset(buffer, 0, len);
 901
 902         /* We need to verify that the actual device will quiesce; the
 903          * later target quiesce is just a nice to have */
 904         if (unlikely(scsi_device_quiesce(sdev)))
 905                 goto out_free;
 906
 907         scsi_target_quiesce(starget);
 908
 909         spi_dv_pending(starget) = 1;
 910         down(&spi_dv_sem(starget));
 911
 912         SPI_PRINTK(starget, KERN_INFO, "Beginning Domain Validation\n");
 913
 914         spi_dv_device_internal(sreq, buffer);
 915
 916         SPI_PRINTK(starget, KERN_INFO, "Ending Domain Validation\n");
 917
 918         up(&spi_dv_sem(starget));
 919         spi_dv_pending(starget) = 0;
 920
 921         scsi_target_resume(starget);
 922
 923         spi_initial_dv(starget) = 1;
 924
 925  out_free:
 926         kfree(buffer);
 927  out_put:
 928         scsi_device_put(sdev);
 929  out_free_req:
 930         scsi_release_request(sreq);
 931 }
 932 EXPORT_SYMBOL(spi_dv_device);
 933
 934 struct work_queue_wrapper {
 935         struct work_struct      work;
 936         struct scsi_device      *sdev;
 937 };
 938
 939 static void
 940 spi_dv_device_work_wrapper(void *data)
 941 {
 942         struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
 943         struct scsi_device *sdev = wqw->sdev;
 944
 945         kfree(wqw);
 946         spi_dv_device(sdev);
 947         spi_dv_pending(sdev->sdev_target) = 0;
 948         scsi_device_put(sdev);
 949 }
 950
 951
 952 /**
 953  *      spi_schedule_dv_device - schedule domain validation to occur on the device
 954  *      @sdev:  The device to validate
 955  *
 956  *      Identical to spi_dv_device() above, except that the DV will be
 957  *      scheduled to occur in a workqueue later.  All memory allocations
 958  *      are atomic, so may be called from any context including those holding
 959  *      SCSI locks.
 960  */
 961 void
 962 spi_schedule_dv_device(struct scsi_device *sdev)
 963 {
 964         struct work_queue_wrapper *wqw =
 965                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
 966
 967         if (unlikely(!wqw))
 968                 return;
 969
 970         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
 971                 kfree(wqw);
 972                 return;
 973         }
 974         /* Set pending early (dv_device doesn't check it, only sets it) */
 975         spi_dv_pending(sdev->sdev_target) = 1;
 976         if (unlikely(scsi_device_get(sdev))) {
 977                 kfree(wqw);
 978                 spi_dv_pending(sdev->sdev_target) = 0;
 979                 return;
 980         }
 981
 982         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
 983         wqw->sdev = sdev;
 984
 985         schedule_work(&wqw->work);
 986 }
 987 EXPORT_SYMBOL(spi_schedule_dv_device);
 988
 989 /**
 990  * spi_display_xfer_agreement - Print the current target transfer agreement
 991  * @starget: The target for which to display the agreement
 992  *
 993  * Each SPI port is required to maintain a transfer agreement for each
 994  * other port on the bus.  This function prints a one-line summary of
 995  * the current agreement; more detailed information is available in sysfs.
 996  */
 997 void spi_display_xfer_agreement(struct scsi_target *starget)
 998 {
 999         struct spi_transport_attrs *tp;
1000         tp = (struct spi_transport_attrs *)&starget->starget_data;
1001
1002         if (tp->offset > 0 && tp->period > 0) {
1003                 unsigned int picosec, kb100;
1004                 char *scsi = "FAST-?";
1005                 char tmp[8];
1006
1007                 if (tp->period <= SPI_STATIC_PPR) {
1008                         picosec = ppr_to_ps[tp->period];
1009                         switch (tp->period) {
1010                                 case  7: scsi = "FAST-320"; break;
1011                                 case  8: scsi = "FAST-160"; break;
1012                                 case  9: scsi = "FAST-80"; break;
1013                                 case 10:
1014                                 case 11: scsi = "FAST-40"; break;
1015                                 case 12: scsi = "FAST-20"; break;
1016                         }
1017                 } else {
1018                         picosec = tp->period * 4000;
1019                         if (tp->period < 25)
1020                                 scsi = "FAST-20";
1021                         else if (tp->period < 50)
1022                                 scsi = "FAST-10";
1023                         else
1024                                 scsi = "FAST-5";
1025                 }
1026
1027                 kb100 = (10000000 + picosec / 2) / picosec;
1028                 if (tp->width)
1029                         kb100 *= 2;
1030                 sprint_frac(tmp, picosec, 1000);
1031
1032                 dev_info(&starget->dev,
1033                          "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1034                          scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1035                          tp->dt ? "DT" : "ST",
1036                          tp->iu ? " IU" : "",
1037                          tp->qas  ? " QAS" : "",
1038                          tp->rd_strm ? " RDSTRM" : "",
1039                          tp->rti ? " RTI" : "",
1040                          tp->wr_flow ? " WRFLOW" : "",
1041                          tp->pcomp_en ? " PCOMP" : "",
1042                          tp->hold_mcs ? " HMCS" : "",
1043                          tmp, tp->offset);
1044         } else {
1045                 dev_info(&starget->dev, "%sasynchronous.\n",
1046                                 tp->width ? "wide " : "");
1047         }
1048 }
1049 EXPORT_SYMBOL(spi_display_xfer_agreement);
1050
1051 #define SETUP_ATTRIBUTE(field)                                          \
1052         i->private_attrs[count] = class_device_attr_##field;            \
1053         if (!i->f->set_##field) {                                       \
1054                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1055                 i->private_attrs[count].store = NULL;                   \
1056         }                                                               \
1057         i->attrs[count] = &i->private_attrs[count];                     \
1058         if (i->f->show_##field)                                         \
1059                 count++
1060
1061 #define SETUP_RELATED_ATTRIBUTE(field, rel_field)                       \
1062         i->private_attrs[count] = class_device_attr_##field;            \
1063         if (!i->f->set_##rel_field) {                                   \
1064                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1065                 i->private_attrs[count].store = NULL;                   \
1066         }                                                               \
1067         i->attrs[count] = &i->private_attrs[count];                     \
1068         if (i->f->show_##rel_field)                                     \
1069                 count++
1070
1071 #define SETUP_HOST_ATTRIBUTE(field)                                     \
1072         i->private_host_attrs[count] = class_device_attr_##field;       \
1073         if (!i->f->set_##field) {                                       \
1074                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
1075                 i->private_host_attrs[count].store = NULL;              \
1076         }                                                               \
1077         i->host_attrs[count] = &i->private_host_attrs[count];           \
1078         count++
1079
1080 static int spi_device_match(struct attribute_container *cont,
1081                             struct device *dev)
1082 {
1083         struct scsi_device *sdev;
1084         struct Scsi_Host *shost;
1085         struct spi_internal *i;
1086
1087         if (!scsi_is_sdev_device(dev))
1088                 return 0;
1089
1090         sdev = to_scsi_device(dev);
1091         shost = sdev->host;
1092         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1093             != &spi_host_class.class)
1094                 return 0;
1095         /* Note: this class has no device attributes, so it has
1096          * no per-HBA allocation and thus we don't need to distinguish
1097          * the attribute containers for the device */
1098         i = to_spi_internal(shost->transportt);
1099         if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1100                 return 0;
1101         return 1;
1102 }
1103
1104 static int spi_target_match(struct attribute_container *cont,
1105                             struct device *dev)
1106 {
1107         struct Scsi_Host *shost;
1108         struct scsi_target *starget;
1109         struct spi_internal *i;
1110
1111         if (!scsi_is_target_device(dev))
1112                 return 0;
1113
1114         shost = dev_to_shost(dev->parent);
1115         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1116             != &spi_host_class.class)
1117                 return 0;
1118
1119         i = to_spi_internal(shost->transportt);
1120         starget = to_scsi_target(dev);
1121
1122         if (i->f->deny_binding && i->f->deny_binding(starget))
1123                 return 0;
1124
1125         return &i->t.target_attrs.ac == cont;
1126 }
1127
1128 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1129                                "spi_transport",
1130                                spi_setup_transport_attrs,
1131                                NULL,
1132                                NULL);
1133
1134 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1135                                     spi_device_match,
1136                                     spi_device_configure);
1137
1138 struct scsi_transport_template *
1139 spi_attach_transport(struct spi_function_template *ft)
1140 {
1141         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
1142                                          GFP_KERNEL);
1143         int count = 0;
1144         if (unlikely(!i))
1145                 return NULL;
1146
1147         memset(i, 0, sizeof(struct spi_internal));
1148
1149
1150         i->t.target_attrs.ac.class = &spi_transport_class.class;
1151         i->t.target_attrs.ac.attrs = &i->attrs[0];
1152         i->t.target_attrs.ac.match = spi_target_match;
1153         transport_container_register(&i->t.target_attrs);
1154         i->t.target_size = sizeof(struct spi_transport_attrs);
1155         i->t.host_attrs.ac.class = &spi_host_class.class;
1156         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
1157         i->t.host_attrs.ac.match = spi_host_match;
1158         transport_container_register(&i->t.host_attrs);
1159         i->t.host_size = sizeof(struct spi_host_attrs);
1160         i->f = ft;
1161
1162         SETUP_ATTRIBUTE(period);
1163         SETUP_RELATED_ATTRIBUTE(min_period, period);
1164         SETUP_ATTRIBUTE(offset);
1165         SETUP_RELATED_ATTRIBUTE(max_offset, offset);
1166         SETUP_ATTRIBUTE(width);
1167         SETUP_RELATED_ATTRIBUTE(max_width, width);
1168         SETUP_ATTRIBUTE(iu);
1169         SETUP_ATTRIBUTE(dt);
1170         SETUP_ATTRIBUTE(qas);
1171         SETUP_ATTRIBUTE(wr_flow);
1172         SETUP_ATTRIBUTE(rd_strm);
1173         SETUP_ATTRIBUTE(rti);
1174         SETUP_ATTRIBUTE(pcomp_en);
1175         SETUP_ATTRIBUTE(hold_mcs);
1176
1177         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
1178          * this bug will trigger */
1179         BUG_ON(count > SPI_NUM_ATTRS);
1180
1181         i->attrs[count++] = &class_device_attr_revalidate;
1182
1183         i->attrs[count] = NULL;
1184
1185         count = 0;
1186         SETUP_HOST_ATTRIBUTE(signalling);
1187
1188         BUG_ON(count > SPI_HOST_ATTRS);
1189
1190         i->host_attrs[count] = NULL;
1191
1192         return &i->t;
1193 }
1194 EXPORT_SYMBOL(spi_attach_transport);
1195
1196 void spi_release_transport(struct scsi_transport_template *t)
1197 {
1198         struct spi_internal *i = to_spi_internal(t);
1199
1200         transport_container_unregister(&i->t.target_attrs);
1201         transport_container_unregister(&i->t.host_attrs);
1202
1203         kfree(i);
1204 }
1205 EXPORT_SYMBOL(spi_release_transport);
1206
1207 static __init int spi_transport_init(void)
1208 {
1209         int error = transport_class_register(&spi_transport_class);
1210         if (error)
1211                 return error;
1212         error = anon_transport_class_register(&spi_device_class);
1213         return transport_class_register(&spi_host_class);
1214 }
1215
1216 static void __exit spi_transport_exit(void)
1217 {
1218         transport_class_unregister(&spi_transport_class);
1219         anon_transport_class_unregister(&spi_device_class);
1220         transport_class_unregister(&spi_host_class);
1221 }
1222
1223 MODULE_AUTHOR("Martin Hicks");
1224 MODULE_DESCRIPTION("SPI Transport Attributes");
1225 MODULE_LICENSE("GPL");
1226
1227 module_init(spi_transport_init);
1228 module_exit(spi_transport_exit);