git.oblomov.eu Git - linux-2.6/blob - drivers/scsi/scsi_transport_spi.c

   1 /*
   2  *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
   3  *
   4  *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
   5  *  Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21 #include <linux/ctype.h>
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/workqueue.h>
  25 #include <asm/semaphore.h>
  26 #include <scsi/scsi.h>
  27 #include "scsi_priv.h"
  28 #include <scsi/scsi_device.h>
  29 #include <scsi/scsi_host.h>
  30 #include <scsi/scsi_request.h>
  31 #include <scsi/scsi_eh.h>
  32 #include <scsi/scsi_transport.h>
  33 #include <scsi/scsi_transport_spi.h>
  34
  35 #define SPI_PRINTK(x, l, f, a...)       dev_printk(l, &(x)->dev, f , ##a)
  36
  37 #define SPI_NUM_ATTRS 10        /* increase this if you add attributes */
  38 #define SPI_OTHER_ATTRS 1       /* Increase this if you add "always
  39                                  * on" attributes */
  40 #define SPI_HOST_ATTRS  1
  41
  42 #define SPI_MAX_ECHO_BUFFER_SIZE        4096
  43
  44 /* Private data accessors (keep these out of the header file) */
  45 #define spi_dv_pending(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_pending)
  46 #define spi_dv_sem(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_sem)
  47
  48 struct spi_internal {
  49         struct scsi_transport_template t;
  50         struct spi_function_template *f;
  51         /* The actual attributes */
  52         struct class_device_attribute private_attrs[SPI_NUM_ATTRS];
  53         /* The array of null terminated pointers to attributes
  54          * needed by scsi_sysfs.c */
  55         struct class_device_attribute *attrs[SPI_NUM_ATTRS + SPI_OTHER_ATTRS + 1];
  56         struct class_device_attribute private_host_attrs[SPI_HOST_ATTRS];
  57         struct class_device_attribute *host_attrs[SPI_HOST_ATTRS + 1];
  58 };
  59
  60 #define to_spi_internal(tmpl)   container_of(tmpl, struct spi_internal, t)
  61
  62 static const int ppr_to_ps[] = {
  63         /* The PPR values 0-6 are reserved, fill them in when
  64          * the committee defines them */
  65         -1,                     /* 0x00 */
  66         -1,                     /* 0x01 */
  67         -1,                     /* 0x02 */
  68         -1,                     /* 0x03 */
  69         -1,                     /* 0x04 */
  70         -1,                     /* 0x05 */
  71         -1,                     /* 0x06 */
  72          3125,                  /* 0x07 */
  73          6250,                  /* 0x08 */
  74         12500,                  /* 0x09 */
  75         25000,                  /* 0x0a */
  76         30300,                  /* 0x0b */
  77         50000,                  /* 0x0c */
  78 };
  79 /* The PPR values at which you calculate the period in ns by multiplying
  80  * by 4 */
  81 #define SPI_STATIC_PPR  0x0c
  82
  83 static int sprint_frac(char *dest, int value, int denom)
  84 {
  85         int frac = value % denom;
  86         int result = sprintf(dest, "%d", value / denom);
  87
  88         if (frac == 0)
  89                 return result;
  90         dest[result++] = '.';
  91
  92         do {
  93                 denom /= 10;
  94                 sprintf(dest + result, "%d", frac / denom);
  95                 result++;
  96                 frac %= denom;
  97         } while (frac);
  98
  99         dest[result++] = '\0';
 100         return result;
 101 }
 102
 103 static struct {
 104         enum spi_signal_type    value;
 105         char                    *name;
 106 } signal_types[] = {
 107         { SPI_SIGNAL_UNKNOWN, "unknown" },
 108         { SPI_SIGNAL_SE, "SE" },
 109         { SPI_SIGNAL_LVD, "LVD" },
 110         { SPI_SIGNAL_HVD, "HVD" },
 111 };
 112
 113 static inline const char *spi_signal_to_string(enum spi_signal_type type)
 114 {
 115         int i;
 116
 117         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 118                 if (type == signal_types[i].value)
 119                         return signal_types[i].name;
 120         }
 121         return NULL;
 122 }
 123 static inline enum spi_signal_type spi_signal_to_value(const char *name)
 124 {
 125         int i, len;
 126
 127         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 128                 len =  strlen(signal_types[i].name);
 129                 if (strncmp(name, signal_types[i].name, len) == 0 &&
 130                     (name[len] == '\n' || name[len] == '\0'))
 131                         return signal_types[i].value;
 132         }
 133         return SPI_SIGNAL_UNKNOWN;
 134 }
 135
 136 static int spi_host_setup(struct device *dev)
 137 {
 138         struct Scsi_Host *shost = dev_to_shost(dev);
 139
 140         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
 141
 142         return 0;
 143 }
 144
 145 static DECLARE_TRANSPORT_CLASS(spi_host_class,
 146                                "spi_host",
 147                                spi_host_setup,
 148                                NULL,
 149                                NULL);
 150
 151 static int spi_host_match(struct attribute_container *cont,
 152                           struct device *dev)
 153 {
 154         struct Scsi_Host *shost;
 155         struct spi_internal *i;
 156
 157         if (!scsi_is_host_device(dev))
 158                 return 0;
 159
 160         shost = dev_to_shost(dev);
 161         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
 162             != &spi_host_class.class)
 163                 return 0;
 164
 165         i = to_spi_internal(shost->transportt);
 166
 167         return &i->t.host_attrs.ac == cont;
 168 }
 169
 170 static int spi_device_configure(struct device *dev)
 171 {
 172         struct scsi_device *sdev = to_scsi_device(dev);
 173         struct scsi_target *starget = sdev->sdev_target;
 174
 175         /* Populate the target capability fields with the values
 176          * gleaned from the device inquiry */
 177
 178         spi_support_sync(starget) = scsi_device_sync(sdev);
 179         spi_support_wide(starget) = scsi_device_wide(sdev);
 180         spi_support_dt(starget) = scsi_device_dt(sdev);
 181         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
 182         spi_support_ius(starget) = scsi_device_ius(sdev);
 183         spi_support_qas(starget) = scsi_device_qas(sdev);
 184
 185         return 0;
 186 }
 187
 188 static int spi_setup_transport_attrs(struct device *dev)
 189 {
 190         struct scsi_target *starget = to_scsi_target(dev);
 191
 192         spi_period(starget) = -1;       /* illegal value */
 193         spi_offset(starget) = 0;        /* async */
 194         spi_width(starget) = 0; /* narrow */
 195         spi_iu(starget) = 0;    /* no IU */
 196         spi_dt(starget) = 0;    /* ST */
 197         spi_qas(starget) = 0;
 198         spi_wr_flow(starget) = 0;
 199         spi_rd_strm(starget) = 0;
 200         spi_rti(starget) = 0;
 201         spi_pcomp_en(starget) = 0;
 202         spi_dv_pending(starget) = 0;
 203         spi_initial_dv(starget) = 0;
 204         init_MUTEX(&spi_dv_sem(starget));
 205
 206         return 0;
 207 }
 208
 209 #define spi_transport_show_function(field, format_string)               \
 210                                                                         \
 211 static ssize_t                                                          \
 212 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
 213 {                                                                       \
 214         struct scsi_target *starget = transport_class_to_starget(cdev); \
 215         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 216         struct spi_transport_attrs *tp;                                 \
 217         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 218         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
 219         if (i->f->get_##field)                                          \
 220                 i->f->get_##field(starget);                             \
 221         return snprintf(buf, 20, format_string, tp->field);             \
 222 }
 223
 224 #define spi_transport_store_function(field, format_string)              \
 225 static ssize_t                                                          \
 226 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
 227                             size_t count)                               \
 228 {                                                                       \
 229         int val;                                                        \
 230         struct scsi_target *starget = transport_class_to_starget(cdev); \
 231         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 232         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 233                                                                         \
 234         val = simple_strtoul(buf, NULL, 0);                             \
 235         i->f->set_##field(starget, val);                                \
 236         return count;                                                   \
 237 }
 238
 239 #define spi_transport_rd_attr(field, format_string)                     \
 240         spi_transport_show_function(field, format_string)               \
 241         spi_transport_store_function(field, format_string)              \
 242 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
 243                          show_spi_transport_##field,                    \
 244                          store_spi_transport_##field);
 245
 246 /* The Parallel SCSI Tranport Attributes: */
 247 spi_transport_rd_attr(offset, "%d\n");
 248 spi_transport_rd_attr(width, "%d\n");
 249 spi_transport_rd_attr(iu, "%d\n");
 250 spi_transport_rd_attr(dt, "%d\n");
 251 spi_transport_rd_attr(qas, "%d\n");
 252 spi_transport_rd_attr(wr_flow, "%d\n");
 253 spi_transport_rd_attr(rd_strm, "%d\n");
 254 spi_transport_rd_attr(rti, "%d\n");
 255 spi_transport_rd_attr(pcomp_en, "%d\n");
 256
 257 static ssize_t
 258 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
 259 {
 260         struct scsi_target *starget = transport_class_to_starget(cdev);
 261
 262         /* FIXME: we're relying on an awful lot of device internals
 263          * here.  We really need a function to get the first available
 264          * child */
 265         struct device *dev = container_of(starget->dev.children.next, struct device, node);
 266         struct scsi_device *sdev = to_scsi_device(dev);
 267         spi_dv_device(sdev);
 268         return count;
 269 }
 270 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
 271
 272 /* Translate the period into ns according to the current spec
 273  * for SDTR/PPR messages */
 274 static ssize_t show_spi_transport_period(struct class_device *cdev, char *buf)
 275
 276 {
 277         struct scsi_target *starget = transport_class_to_starget(cdev);
 278         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 279         struct spi_transport_attrs *tp;
 280         int len, picosec;
 281         struct spi_internal *i = to_spi_internal(shost->transportt);
 282
 283         tp = (struct spi_transport_attrs *)&starget->starget_data;
 284
 285         if (i->f->get_period)
 286                 i->f->get_period(starget);
 287
 288         if (tp->period < 0 || tp->period > 0xff) {
 289                 picosec = -1;
 290         } else if (tp->period <= SPI_STATIC_PPR) {
 291                 picosec = ppr_to_ps[tp->period];
 292         } else {
 293                 picosec = tp->period * 4000;
 294         }
 295
 296         if (picosec == -1) {
 297                 len = sprintf(buf, "reserved");
 298         } else {
 299                 len = sprint_frac(buf, picosec, 1000);
 300         }
 301
 302         buf[len++] = '\n';
 303         buf[len] = '\0';
 304         return len;
 305 }
 306
 307 static ssize_t
 308 store_spi_transport_period(struct class_device *cdev, const char *buf,
 309                             size_t count)
 310 {
 311         struct scsi_target *starget = transport_class_to_starget(cdev);
 312         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 313         struct spi_internal *i = to_spi_internal(shost->transportt);
 314         int j, picosec, period = -1;
 315         char *endp;
 316
 317         picosec = simple_strtoul(buf, &endp, 10) * 1000;
 318         if (*endp == '.') {
 319                 int mult = 100;
 320                 do {
 321                         endp++;
 322                         if (!isdigit(*endp))
 323                                 break;
 324                         picosec += (*endp - '0') * mult;
 325                         mult /= 10;
 326                 } while (mult > 0);
 327         }
 328
 329         for (j = 0; j <= SPI_STATIC_PPR; j++) {
 330                 if (ppr_to_ps[j] < picosec)
 331                         continue;
 332                 period = j;
 333                 break;
 334         }
 335
 336         if (period == -1)
 337                 period = picosec / 4000;
 338
 339         if (period > 0xff)
 340                 period = 0xff;
 341
 342         i->f->set_period(starget, period);
 343
 344         return count;
 345 }
 346
 347 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
 348                          show_spi_transport_period,
 349                          store_spi_transport_period);
 350
 351 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
 352 {
 353         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 354         struct spi_internal *i = to_spi_internal(shost->transportt);
 355
 356         if (i->f->get_signalling)
 357                 i->f->get_signalling(shost);
 358
 359         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
 360 }
 361 static ssize_t store_spi_host_signalling(struct class_device *cdev,
 362                                          const char *buf, size_t count)
 363 {
 364         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 365         struct spi_internal *i = to_spi_internal(shost->transportt);
 366         enum spi_signal_type type = spi_signal_to_value(buf);
 367
 368         if (type != SPI_SIGNAL_UNKNOWN)
 369                 i->f->set_signalling(shost, type);
 370
 371         return count;
 372 }
 373 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
 374                          show_spi_host_signalling,
 375                          store_spi_host_signalling);
 376
 377 #define DV_SET(x, y)                    \
 378         if(i->f->set_##x)               \
 379                 i->f->set_##x(sdev->sdev_target, y)
 380
 381 #define DV_LOOPS        3
 382 #define DV_TIMEOUT      (10*HZ)
 383 #define DV_RETRIES      3       /* should only need at most
 384                                  * two cc/ua clears */
 385
 386 enum spi_compare_returns {
 387         SPI_COMPARE_SUCCESS,
 388         SPI_COMPARE_FAILURE,
 389         SPI_COMPARE_SKIP_TEST,
 390 };
 391
 392
 393 /* This is for read/write Domain Validation:  If the device supports
 394  * an echo buffer, we do read/write tests to it */
 395 static enum spi_compare_returns
 396 spi_dv_device_echo_buffer(struct scsi_request *sreq, u8 *buffer,
 397                           u8 *ptr, const int retries)
 398 {
 399         struct scsi_device *sdev = sreq->sr_device;
 400         int len = ptr - buffer;
 401         int j, k, r;
 402         unsigned int pattern = 0x0000ffff;
 403
 404         const char spi_write_buffer[] = {
 405                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 406         };
 407         const char spi_read_buffer[] = {
 408                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 409         };
 410
 411         /* set up the pattern buffer.  Doesn't matter if we spill
 412          * slightly beyond since that's where the read buffer is */
 413         for (j = 0; j < len; ) {
 414
 415                 /* fill the buffer with counting (test a) */
 416                 for ( ; j < min(len, 32); j++)
 417                         buffer[j] = j;
 418                 k = j;
 419                 /* fill the buffer with alternating words of 0x0 and
 420                  * 0xffff (test b) */
 421                 for ( ; j < min(len, k + 32); j += 2) {
 422                         u16 *word = (u16 *)&buffer[j];
 423
 424                         *word = (j & 0x02) ? 0x0000 : 0xffff;
 425                 }
 426                 k = j;
 427                 /* fill with crosstalk (alternating 0x5555 0xaaa)
 428                  * (test c) */
 429                 for ( ; j < min(len, k + 32); j += 2) {
 430                         u16 *word = (u16 *)&buffer[j];
 431
 432                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
 433                 }
 434                 k = j;
 435                 /* fill with shifting bits (test d) */
 436                 for ( ; j < min(len, k + 32); j += 4) {
 437                         u32 *word = (unsigned int *)&buffer[j];
 438                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
 439
 440                         *word = pattern;
 441                         pattern = (pattern << 1) | roll;
 442                 }
 443                 /* don't bother with random data (test e) */
 444         }
 445
 446         for (r = 0; r < retries; r++) {
 447                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 448                 sreq->sr_data_direction = DMA_TO_DEVICE;
 449                 scsi_wait_req(sreq, spi_write_buffer, buffer, len,
 450                               DV_TIMEOUT, DV_RETRIES);
 451                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 452                         struct scsi_sense_hdr sshdr;
 453
 454                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 455                         if (scsi_request_normalize_sense(sreq, &sshdr)
 456                             && sshdr.sense_key == ILLEGAL_REQUEST
 457                             /* INVALID FIELD IN CDB */
 458                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
 459                                 /* This would mean that the drive lied
 460                                  * to us about supporting an echo
 461                                  * buffer (unfortunately some Western
 462                                  * Digital drives do precisely this)
 463                                  */
 464                                 return SPI_COMPARE_SKIP_TEST;
 465
 466
 467                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Write Buffer failure %x\n", sreq->sr_result);
 468                         return SPI_COMPARE_FAILURE;
 469                 }
 470
 471                 memset(ptr, 0, len);
 472                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 473                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 474                 scsi_wait_req(sreq, spi_read_buffer, ptr, len,
 475                               DV_TIMEOUT, DV_RETRIES);
 476                 scsi_device_set_state(sdev, SDEV_QUIESCE);
 477
 478                 if (memcmp(buffer, ptr, len) != 0)
 479                         return SPI_COMPARE_FAILURE;
 480         }
 481         return SPI_COMPARE_SUCCESS;
 482 }
 483
 484 /* This is for the simplest form of Domain Validation: a read test
 485  * on the inquiry data from the device */
 486 static enum spi_compare_returns
 487 spi_dv_device_compare_inquiry(struct scsi_request *sreq, u8 *buffer,
 488                               u8 *ptr, const int retries)
 489 {
 490         int r;
 491         const int len = sreq->sr_device->inquiry_len;
 492         struct scsi_device *sdev = sreq->sr_device;
 493         const char spi_inquiry[] = {
 494                 INQUIRY, 0, 0, 0, len, 0
 495         };
 496
 497         for (r = 0; r < retries; r++) {
 498                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 499                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 500
 501                 memset(ptr, 0, len);
 502
 503                 scsi_wait_req(sreq, spi_inquiry, ptr, len,
 504                               DV_TIMEOUT, DV_RETRIES);
 505
 506                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 507                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 508                         return SPI_COMPARE_FAILURE;
 509                 }
 510
 511                 /* If we don't have the inquiry data already, the
 512                  * first read gets it */
 513                 if (ptr == buffer) {
 514                         ptr += len;
 515                         --r;
 516                         continue;
 517                 }
 518
 519                 if (memcmp(buffer, ptr, len) != 0)
 520                         /* failure */
 521                         return SPI_COMPARE_FAILURE;
 522         }
 523         return SPI_COMPARE_SUCCESS;
 524 }
 525
 526 static enum spi_compare_returns
 527 spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
 528                enum spi_compare_returns
 529                (*compare_fn)(struct scsi_request *, u8 *, u8 *, int))
 530 {
 531         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 532         struct scsi_device *sdev = sreq->sr_device;
 533         int period = 0, prevperiod = 0;
 534         enum spi_compare_returns retval;
 535
 536
 537         for (;;) {
 538                 int newperiod;
 539                 retval = compare_fn(sreq, buffer, ptr, DV_LOOPS);
 540
 541                 if (retval == SPI_COMPARE_SUCCESS
 542                     || retval == SPI_COMPARE_SKIP_TEST)
 543                         break;
 544
 545                 /* OK, retrain, fallback */
 546                 if (i->f->get_period)
 547                         i->f->get_period(sdev->sdev_target);
 548                 newperiod = spi_period(sdev->sdev_target);
 549                 period = newperiod > period ? newperiod : period;
 550                 if (period < 0x0d)
 551                         period++;
 552                 else
 553                         period += period >> 1;
 554
 555                 if (unlikely(period > 0xff || period == prevperiod)) {
 556                         /* Total failure; set to async and return */
 557                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
 558                         DV_SET(offset, 0);
 559                         return SPI_COMPARE_FAILURE;
 560                 }
 561                 SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation detected failure, dropping back\n");
 562                 DV_SET(period, period);
 563                 prevperiod = period;
 564         }
 565         return retval;
 566 }
 567
 568 static int
 569 spi_dv_device_get_echo_buffer(struct scsi_request *sreq, u8 *buffer)
 570 {
 571         int l;
 572
 573         /* first off do a test unit ready.  This can error out
 574          * because of reservations or some other reason.  If it
 575          * fails, the device won't let us write to the echo buffer
 576          * so just return failure */
 577
 578         const char spi_test_unit_ready[] = {
 579                 TEST_UNIT_READY, 0, 0, 0, 0, 0
 580         };
 581
 582         const char spi_read_buffer_descriptor[] = {
 583                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
 584         };
 585
 586
 587         sreq->sr_cmd_len = 0;
 588         sreq->sr_data_direction = DMA_NONE;
 589
 590         /* We send a set of three TURs to clear any outstanding
 591          * unit attention conditions if they exist (Otherwise the
 592          * buffer tests won't be happy).  If the TUR still fails
 593          * (reservation conflict, device not ready, etc) just
 594          * skip the write tests */
 595         for (l = 0; ; l++) {
 596                 scsi_wait_req(sreq, spi_test_unit_ready, NULL, 0,
 597                               DV_TIMEOUT, DV_RETRIES);
 598
 599                 if(sreq->sr_result) {
 600                         if(l >= 3)
 601                                 return 0;
 602                 } else {
 603                         /* TUR succeeded */
 604                         break;
 605                 }
 606         }
 607
 608         sreq->sr_cmd_len = 0;
 609         sreq->sr_data_direction = DMA_FROM_DEVICE;
 610
 611         scsi_wait_req(sreq, spi_read_buffer_descriptor, buffer, 4,
 612                       DV_TIMEOUT, DV_RETRIES);
 613
 614         if (sreq->sr_result)
 615                 /* Device has no echo buffer */
 616                 return 0;
 617
 618         return buffer[3] + ((buffer[2] & 0x1f) << 8);
 619 }
 620
 621 static void
 622 spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
 623 {
 624         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 625         struct scsi_device *sdev = sreq->sr_device;
 626         int len = sdev->inquiry_len;
 627         /* first set us up for narrow async */
 628         DV_SET(offset, 0);
 629         DV_SET(width, 0);
 630
 631         if (spi_dv_device_compare_inquiry(sreq, buffer, buffer, DV_LOOPS)
 632             != SPI_COMPARE_SUCCESS) {
 633                 SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
 634                 /* FIXME: should probably offline the device here? */
 635                 return;
 636         }
 637
 638         /* test width */
 639         if (i->f->set_width && sdev->wdtr) {
 640                 i->f->set_width(sdev->sdev_target, 1);
 641
 642                 if (spi_dv_device_compare_inquiry(sreq, buffer,
 643                                                    buffer + len,
 644                                                    DV_LOOPS)
 645                     != SPI_COMPARE_SUCCESS) {
 646                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Wide Transfers Fail\n");
 647                         i->f->set_width(sdev->sdev_target, 0);
 648                 }
 649         }
 650
 651         if (!i->f->set_period)
 652                 return;
 653
 654         /* device can't handle synchronous */
 655         if(!sdev->ppr && !sdev->sdtr)
 656                 return;
 657
 658         /* see if the device has an echo buffer.  If it does we can
 659          * do the SPI pattern write tests */
 660
 661         len = 0;
 662         if (sdev->ppr)
 663                 len = spi_dv_device_get_echo_buffer(sreq, buffer);
 664
 665  retry:
 666
 667         /* now set up to the maximum */
 668         DV_SET(offset, 255);
 669         DV_SET(period, 1);
 670
 671         if (len == 0) {
 672                 SPI_PRINTK(sdev->sdev_target, KERN_INFO, "Domain Validation skipping write tests\n");
 673                 spi_dv_retrain(sreq, buffer, buffer + len,
 674                                spi_dv_device_compare_inquiry);
 675                 return;
 676         }
 677
 678         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
 679                 SPI_PRINTK(sdev->sdev_target, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
 680                 len = SPI_MAX_ECHO_BUFFER_SIZE;
 681         }
 682
 683         if (spi_dv_retrain(sreq, buffer, buffer + len,
 684                            spi_dv_device_echo_buffer)
 685             == SPI_COMPARE_SKIP_TEST) {
 686                 /* OK, the stupid drive can't do a write echo buffer
 687                  * test after all, fall back to the read tests */
 688                 len = 0;
 689                 goto retry;
 690         }
 691 }
 692
 693
 694 /**     spi_dv_device - Do Domain Validation on the device
 695  *      @sdev:          scsi device to validate
 696  *
 697  *      Performs the domain validation on the given device in the
 698  *      current execution thread.  Since DV operations may sleep,
 699  *      the current thread must have user context.  Also no SCSI
 700  *      related locks that would deadlock I/O issued by the DV may
 701  *      be held.
 702  */
 703 void
 704 spi_dv_device(struct scsi_device *sdev)
 705 {
 706         struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL);
 707         struct scsi_target *starget = sdev->sdev_target;
 708         u8 *buffer;
 709         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
 710
 711         if (unlikely(!sreq))
 712                 return;
 713
 714         if (unlikely(scsi_device_get(sdev)))
 715                 goto out_free_req;
 716
 717         buffer = kmalloc(len, GFP_KERNEL);
 718
 719         if (unlikely(!buffer))
 720                 goto out_put;
 721
 722         memset(buffer, 0, len);
 723
 724         /* We need to verify that the actual device will quiesce; the
 725          * later target quiesce is just a nice to have */
 726         if (unlikely(scsi_device_quiesce(sdev)))
 727                 goto out_free;
 728
 729         scsi_target_quiesce(starget);
 730
 731         spi_dv_pending(starget) = 1;
 732         down(&spi_dv_sem(starget));
 733
 734         SPI_PRINTK(starget, KERN_INFO, "Beginning Domain Validation\n");
 735
 736         spi_dv_device_internal(sreq, buffer);
 737
 738         SPI_PRINTK(starget, KERN_INFO, "Ending Domain Validation\n");
 739
 740         up(&spi_dv_sem(starget));
 741         spi_dv_pending(starget) = 0;
 742
 743         scsi_target_resume(starget);
 744
 745         spi_initial_dv(starget) = 1;
 746
 747  out_free:
 748         kfree(buffer);
 749  out_put:
 750         scsi_device_put(sdev);
 751  out_free_req:
 752         scsi_release_request(sreq);
 753 }
 754 EXPORT_SYMBOL(spi_dv_device);
 755
 756 struct work_queue_wrapper {
 757         struct work_struct      work;
 758         struct scsi_device      *sdev;
 759 };
 760
 761 static void
 762 spi_dv_device_work_wrapper(void *data)
 763 {
 764         struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
 765         struct scsi_device *sdev = wqw->sdev;
 766
 767         kfree(wqw);
 768         spi_dv_device(sdev);
 769         spi_dv_pending(sdev->sdev_target) = 0;
 770         scsi_device_put(sdev);
 771 }
 772
 773
 774 /**
 775  *      spi_schedule_dv_device - schedule domain validation to occur on the device
 776  *      @sdev:  The device to validate
 777  *
 778  *      Identical to spi_dv_device() above, except that the DV will be
 779  *      scheduled to occur in a workqueue later.  All memory allocations
 780  *      are atomic, so may be called from any context including those holding
 781  *      SCSI locks.
 782  */
 783 void
 784 spi_schedule_dv_device(struct scsi_device *sdev)
 785 {
 786         struct work_queue_wrapper *wqw =
 787                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
 788
 789         if (unlikely(!wqw))
 790                 return;
 791
 792         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
 793                 kfree(wqw);
 794                 return;
 795         }
 796         /* Set pending early (dv_device doesn't check it, only sets it) */
 797         spi_dv_pending(sdev->sdev_target) = 1;
 798         if (unlikely(scsi_device_get(sdev))) {
 799                 kfree(wqw);
 800                 spi_dv_pending(sdev->sdev_target) = 0;
 801                 return;
 802         }
 803
 804         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
 805         wqw->sdev = sdev;
 806
 807         schedule_work(&wqw->work);
 808 }
 809 EXPORT_SYMBOL(spi_schedule_dv_device);
 810
 811 /**
 812  * spi_display_xfer_agreement - Print the current target transfer agreement
 813  * @starget: The target for which to display the agreement
 814  *
 815  * Each SPI port is required to maintain a transfer agreement for each
 816  * other port on the bus.  This function prints a one-line summary of
 817  * the current agreement; more detailed information is available in sysfs.
 818  */
 819 void spi_display_xfer_agreement(struct scsi_target *starget)
 820 {
 821         struct spi_transport_attrs *tp;
 822         tp = (struct spi_transport_attrs *)&starget->starget_data;
 823
 824         if (tp->offset > 0 && tp->period > 0) {
 825                 unsigned int picosec, kb100;
 826                 char *scsi = "FAST-?";
 827                 char tmp[8];
 828
 829                 if (tp->period <= SPI_STATIC_PPR) {
 830                         picosec = ppr_to_ps[tp->period];
 831                         switch (tp->period) {
 832                                 case  7: scsi = "FAST-320"; break;
 833                                 case  8: scsi = "FAST-160"; break;
 834                                 case  9: scsi = "FAST-80"; break;
 835                                 case 10:
 836                                 case 11: scsi = "FAST-40"; break;
 837                                 case 12: scsi = "FAST-20"; break;
 838                         }
 839                 } else {
 840                         picosec = tp->period * 4000;
 841                         if (tp->period < 25)
 842                                 scsi = "FAST-20";
 843                         else if (tp->period < 50)
 844                                 scsi = "FAST-10";
 845                         else
 846                                 scsi = "FAST-5";
 847                 }
 848
 849                 kb100 = (10000000 + picosec / 2) / picosec;
 850                 if (tp->width)
 851                         kb100 *= 2;
 852                 sprint_frac(tmp, picosec, 1000);
 853
 854                 dev_info(&starget->dev,
 855                         "%s %sSCSI %d.%d MB/s %s%s%s (%s ns, offset %d)\n",
 856                         scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
 857                         tp->dt ? "DT" : "ST", tp->iu ? " IU" : "",
 858                         tp->qas  ? " QAS" : "", tmp, tp->offset);
 859         } else {
 860                 dev_info(&starget->dev, "%sasynchronous.\n",
 861                                 tp->width ? "wide " : "");
 862         }
 863 }
 864 EXPORT_SYMBOL(spi_display_xfer_agreement);
 865
 866 #define SETUP_ATTRIBUTE(field)                                          \
 867         i->private_attrs[count] = class_device_attr_##field;            \
 868         if (!i->f->set_##field) {                                       \
 869                 i->private_attrs[count].attr.mode = S_IRUGO;            \
 870                 i->private_attrs[count].store = NULL;                   \
 871         }                                                               \
 872         i->attrs[count] = &i->private_attrs[count];                     \
 873         if (i->f->show_##field)                                         \
 874                 count++
 875
 876 #define SETUP_HOST_ATTRIBUTE(field)                                     \
 877         i->private_host_attrs[count] = class_device_attr_##field;       \
 878         if (!i->f->set_##field) {                                       \
 879                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
 880                 i->private_host_attrs[count].store = NULL;              \
 881         }                                                               \
 882         i->host_attrs[count] = &i->private_host_attrs[count];           \
 883         count++
 884
 885 static int spi_device_match(struct attribute_container *cont,
 886                             struct device *dev)
 887 {
 888         struct scsi_device *sdev;
 889         struct Scsi_Host *shost;
 890
 891         if (!scsi_is_sdev_device(dev))
 892                 return 0;
 893
 894         sdev = to_scsi_device(dev);
 895         shost = sdev->host;
 896         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
 897             != &spi_host_class.class)
 898                 return 0;
 899         /* Note: this class has no device attributes, so it has
 900          * no per-HBA allocation and thus we don't need to distinguish
 901          * the attribute containers for the device */
 902         return 1;
 903 }
 904
 905 static int spi_target_match(struct attribute_container *cont,
 906                             struct device *dev)
 907 {
 908         struct Scsi_Host *shost;
 909         struct spi_internal *i;
 910
 911         if (!scsi_is_target_device(dev))
 912                 return 0;
 913
 914         shost = dev_to_shost(dev->parent);
 915         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
 916             != &spi_host_class.class)
 917                 return 0;
 918
 919         i = to_spi_internal(shost->transportt);
 920
 921         return &i->t.target_attrs.ac == cont;
 922 }
 923
 924 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
 925                                "spi_transport",
 926                                spi_setup_transport_attrs,
 927                                NULL,
 928                                NULL);
 929
 930 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
 931                                     spi_device_match,
 932                                     spi_device_configure);
 933
 934 struct scsi_transport_template *
 935 spi_attach_transport(struct spi_function_template *ft)
 936 {
 937         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
 938                                          GFP_KERNEL);
 939         int count = 0;
 940         if (unlikely(!i))
 941                 return NULL;
 942
 943         memset(i, 0, sizeof(struct spi_internal));
 944
 945
 946         i->t.target_attrs.ac.class = &spi_transport_class.class;
 947         i->t.target_attrs.ac.attrs = &i->attrs[0];
 948         i->t.target_attrs.ac.match = spi_target_match;
 949         transport_container_register(&i->t.target_attrs);
 950         i->t.target_size = sizeof(struct spi_transport_attrs);
 951         i->t.host_attrs.ac.class = &spi_host_class.class;
 952         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
 953         i->t.host_attrs.ac.match = spi_host_match;
 954         transport_container_register(&i->t.host_attrs);
 955         i->t.host_size = sizeof(struct spi_host_attrs);
 956         i->f = ft;
 957
 958         SETUP_ATTRIBUTE(period);
 959         SETUP_ATTRIBUTE(offset);
 960         SETUP_ATTRIBUTE(width);
 961         SETUP_ATTRIBUTE(iu);
 962         SETUP_ATTRIBUTE(dt);
 963         SETUP_ATTRIBUTE(qas);
 964         SETUP_ATTRIBUTE(wr_flow);
 965         SETUP_ATTRIBUTE(rd_strm);
 966         SETUP_ATTRIBUTE(rti);
 967         SETUP_ATTRIBUTE(pcomp_en);
 968
 969         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
 970          * this bug will trigger */
 971         BUG_ON(count > SPI_NUM_ATTRS);
 972
 973         i->attrs[count++] = &class_device_attr_revalidate;
 974
 975         i->attrs[count] = NULL;
 976
 977         count = 0;
 978         SETUP_HOST_ATTRIBUTE(signalling);
 979
 980         BUG_ON(count > SPI_HOST_ATTRS);
 981
 982         i->host_attrs[count] = NULL;
 983
 984         return &i->t;
 985 }
 986 EXPORT_SYMBOL(spi_attach_transport);
 987
 988 void spi_release_transport(struct scsi_transport_template *t)
 989 {
 990         struct spi_internal *i = to_spi_internal(t);
 991
 992         transport_container_unregister(&i->t.target_attrs);
 993         transport_container_unregister(&i->t.host_attrs);
 994
 995         kfree(i);
 996 }
 997 EXPORT_SYMBOL(spi_release_transport);
 998
 999 static __init int spi_transport_init(void)
1000 {
1001         int error = transport_class_register(&spi_transport_class);
1002         if (error)
1003                 return error;
1004         error = anon_transport_class_register(&spi_device_class);
1005         return transport_class_register(&spi_host_class);
1006 }
1007
1008 static void __exit spi_transport_exit(void)
1009 {
1010         transport_class_unregister(&spi_transport_class);
1011         anon_transport_class_unregister(&spi_device_class);
1012         transport_class_unregister(&spi_host_class);
1013 }
1014
1015 MODULE_AUTHOR("Martin Hicks");
1016 MODULE_DESCRIPTION("SPI Transport Attributes");
1017 MODULE_LICENSE("GPL");
1018
1019 module_init(spi_transport_init);
1020 module_exit(spi_transport_exit);