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  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22 #include <linux/smp_lock.h>
  23 #include <linux/list.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/mm.h>
  26 #include <linux/workqueue.h>
  27 #include <asm/scatterlist.h>
  28 #include <asm/io.h>
  29 #include <scsi/scsi.h>
  30 #include "scsi_priv.h"
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_host.h>
  33 #include <scsi/scsi_request.h>
  34 #include <scsi/scsi_eh.h>
  35 #include <scsi/scsi_transport.h>
  36 #include <scsi/scsi_transport_spi.h>
  37
  38 #define SPI_PRINTK(x, l, f, a...)       dev_printk(l, &(x)->dev, f , ##a)
  39
  40 static void transport_class_release(struct class_device *class_dev);
  41 static void host_class_release(struct class_device *class_dev);
  42
  43 #define SPI_NUM_ATTRS 10        /* increase this if you add attributes */
  44 #define SPI_OTHER_ATTRS 1       /* Increase this if you add "always
  45                                  * on" attributes */
  46 #define SPI_HOST_ATTRS  1
  47
  48 #define SPI_MAX_ECHO_BUFFER_SIZE        4096
  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 char *const ppr_to_ns[] = {
  69         /* The PPR values 0-6 are reserved, fill them in when
  70          * the committee defines them */
  71         NULL,                   /* 0x00 */
  72         NULL,                   /* 0x01 */
  73         NULL,                   /* 0x02 */
  74         NULL,                   /* 0x03 */
  75         NULL,                   /* 0x04 */
  76         NULL,                   /* 0x05 */
  77         NULL,                   /* 0x06 */
  78         "3.125",                /* 0x07 */
  79         "6.25",                 /* 0x08 */
  80         "12.5",                 /* 0x09 */
  81         "25",                   /* 0x0a */
  82         "30.3",                 /* 0x0b */
  83         "50",                   /* 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 struct {
  90         enum spi_signal_type    value;
  91         char                    *name;
  92 } signal_types[] = {
  93         { SPI_SIGNAL_UNKNOWN, "unknown" },
  94         { SPI_SIGNAL_SE, "SE" },
  95         { SPI_SIGNAL_LVD, "LVD" },
  96         { SPI_SIGNAL_HVD, "HVD" },
  97 };
  98
  99 static inline const char *spi_signal_to_string(enum spi_signal_type type)
 100 {
 101         int i;
 102
 103         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 104                 if (type == signal_types[i].value)
 105                         return signal_types[i].name;
 106         }
 107         return NULL;
 108 }
 109 static inline enum spi_signal_type spi_signal_to_value(const char *name)
 110 {
 111         int i, len;
 112
 113         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
 114                 len =  strlen(signal_types[i].name);
 115                 if (strncmp(name, signal_types[i].name, len) == 0 &&
 116                     (name[len] == '\n' || name[len] == '\0'))
 117                         return signal_types[i].value;
 118         }
 119         return SPI_SIGNAL_UNKNOWN;
 120 }
 121
 122
 123 struct class spi_transport_class = {
 124         .name = "spi_transport",
 125         .release = transport_class_release,
 126 };
 127
 128 struct class spi_host_class = {
 129         .name = "spi_host",
 130         .release = host_class_release,
 131 };
 132
 133 static __init int spi_transport_init(void)
 134 {
 135         int error = class_register(&spi_host_class);
 136         if (error)
 137                 return error;
 138         return class_register(&spi_transport_class);
 139 }
 140
 141 static void __exit spi_transport_exit(void)
 142 {
 143         class_unregister(&spi_transport_class);
 144         class_unregister(&spi_host_class);
 145 }
 146
 147 static int spi_setup_host_attrs(struct Scsi_Host *shost)
 148 {
 149         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
 150
 151         return 0;
 152 }
 153
 154 static int spi_configure_device(struct scsi_device *sdev)
 155 {
 156         struct scsi_target *starget = sdev->sdev_target;
 157
 158         /* Populate the target capability fields with the values
 159          * gleaned from the device inquiry */
 160
 161         spi_support_sync(starget) = scsi_device_sync(sdev);
 162         spi_support_wide(starget) = scsi_device_wide(sdev);
 163         spi_support_dt(starget) = scsi_device_dt(sdev);
 164         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
 165         spi_support_ius(starget) = scsi_device_ius(sdev);
 166         spi_support_qas(starget) = scsi_device_qas(sdev);
 167
 168         return 0;
 169 }
 170
 171 static int spi_setup_transport_attrs(struct scsi_target *starget)
 172 {
 173         spi_period(starget) = -1;       /* illegal value */
 174         spi_offset(starget) = 0;        /* async */
 175         spi_width(starget) = 0; /* narrow */
 176         spi_iu(starget) = 0;    /* no IU */
 177         spi_dt(starget) = 0;    /* ST */
 178         spi_qas(starget) = 0;
 179         spi_wr_flow(starget) = 0;
 180         spi_rd_strm(starget) = 0;
 181         spi_rti(starget) = 0;
 182         spi_pcomp_en(starget) = 0;
 183         spi_dv_pending(starget) = 0;
 184         spi_initial_dv(starget) = 0;
 185         init_MUTEX(&spi_dv_sem(starget));
 186
 187         return 0;
 188 }
 189
 190 static void transport_class_release(struct class_device *class_dev)
 191 {
 192         struct scsi_target *starget = transport_class_to_starget(class_dev);
 193         put_device(&starget->dev);
 194 }
 195
 196 static void host_class_release(struct class_device *class_dev)
 197 {
 198         struct Scsi_Host *shost = transport_class_to_shost(class_dev);
 199         put_device(&shost->shost_gendev);
 200 }
 201
 202 #define spi_transport_show_function(field, format_string)               \
 203                                                                         \
 204 static ssize_t                                                          \
 205 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
 206 {                                                                       \
 207         struct scsi_target *starget = transport_class_to_starget(cdev); \
 208         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 209         struct spi_transport_attrs *tp;                                 \
 210         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 211         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
 212         if (i->f->get_##field)                                          \
 213                 i->f->get_##field(starget);                             \
 214         return snprintf(buf, 20, format_string, tp->field);             \
 215 }
 216
 217 #define spi_transport_store_function(field, format_string)              \
 218 static ssize_t                                                          \
 219 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
 220                             size_t count)                               \
 221 {                                                                       \
 222         int val;                                                        \
 223         struct scsi_target *starget = transport_class_to_starget(cdev); \
 224         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
 225         struct spi_internal *i = to_spi_internal(shost->transportt);    \
 226                                                                         \
 227         val = simple_strtoul(buf, NULL, 0);                             \
 228         i->f->set_##field(starget, val);                                \
 229         return count;                                                   \
 230 }
 231
 232 #define spi_transport_rd_attr(field, format_string)                     \
 233         spi_transport_show_function(field, format_string)               \
 234         spi_transport_store_function(field, format_string)              \
 235 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
 236                          show_spi_transport_##field,                    \
 237                          store_spi_transport_##field);
 238
 239 /* The Parallel SCSI Tranport Attributes: */
 240 spi_transport_rd_attr(offset, "%d\n");
 241 spi_transport_rd_attr(width, "%d\n");
 242 spi_transport_rd_attr(iu, "%d\n");
 243 spi_transport_rd_attr(dt, "%d\n");
 244 spi_transport_rd_attr(qas, "%d\n");
 245 spi_transport_rd_attr(wr_flow, "%d\n");
 246 spi_transport_rd_attr(rd_strm, "%d\n");
 247 spi_transport_rd_attr(rti, "%d\n");
 248 spi_transport_rd_attr(pcomp_en, "%d\n");
 249
 250 static ssize_t
 251 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
 252 {
 253         struct scsi_target *starget = transport_class_to_starget(cdev);
 254
 255         /* FIXME: we're relying on an awful lot of device internals
 256          * here.  We really need a function to get the first available
 257          * child */
 258         struct device *dev = container_of(starget->dev.children.next, struct device, node);
 259         struct scsi_device *sdev = to_scsi_device(dev);
 260         spi_dv_device(sdev);
 261         return count;
 262 }
 263 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
 264
 265 /* Translate the period into ns according to the current spec
 266  * for SDTR/PPR messages */
 267 static ssize_t show_spi_transport_period(struct class_device *cdev, char *buf)
 268
 269 {
 270         struct scsi_target *starget = transport_class_to_starget(cdev);
 271         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 272         struct spi_transport_attrs *tp;
 273         const char *str;
 274         struct spi_internal *i = to_spi_internal(shost->transportt);
 275
 276         tp = (struct spi_transport_attrs *)&starget->starget_data;
 277
 278         if (i->f->get_period)
 279                 i->f->get_period(starget);
 280
 281         switch(tp->period) {
 282
 283         case 0x07 ... SPI_STATIC_PPR:
 284                 str = ppr_to_ns[tp->period];
 285                 if(!str)
 286                         str = "reserved";
 287                 break;
 288
 289
 290         case (SPI_STATIC_PPR+1) ... 0xff:
 291                 return sprintf(buf, "%d\n", tp->period * 4);
 292
 293         default:
 294                 str = "unknown";
 295         }
 296         return sprintf(buf, "%s\n", str);
 297 }
 298
 299 static ssize_t
 300 store_spi_transport_period(struct class_device *cdev, const char *buf,
 301                             size_t count)
 302 {
 303         struct scsi_target *starget = transport_class_to_starget(cdev);
 304         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 305         struct spi_internal *i = to_spi_internal(shost->transportt);
 306         int j, period = -1;
 307
 308         for (j = 0; j < SPI_STATIC_PPR; j++) {
 309                 int len;
 310
 311                 if(ppr_to_ns[j] == NULL)
 312                         continue;
 313
 314                 len = strlen(ppr_to_ns[j]);
 315
 316                 if(strncmp(ppr_to_ns[j], buf, len) != 0)
 317                         continue;
 318
 319                 if(buf[len] != '\n')
 320                         continue;
 321
 322                 period = j;
 323                 break;
 324         }
 325
 326         if (period == -1) {
 327                 int val = simple_strtoul(buf, NULL, 0);
 328
 329
 330                 /* Should probably check limits here, but this
 331                  * gets reasonably close to OK for most things */
 332                 period = val/4;
 333         }
 334
 335         if (period > 0xff)
 336                 period = 0xff;
 337
 338         i->f->set_period(starget, period);
 339
 340         return count;
 341 }
 342
 343 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
 344                          show_spi_transport_period,
 345                          store_spi_transport_period);
 346
 347 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
 348 {
 349         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 350         struct spi_internal *i = to_spi_internal(shost->transportt);
 351
 352         if (i->f->get_signalling)
 353                 i->f->get_signalling(shost);
 354
 355         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
 356 }
 357 static ssize_t store_spi_host_signalling(struct class_device *cdev,
 358                                          const char *buf, size_t count)
 359 {
 360         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 361         struct spi_internal *i = to_spi_internal(shost->transportt);
 362         enum spi_signal_type type = spi_signal_to_value(buf);
 363
 364         if (type != SPI_SIGNAL_UNKNOWN)
 365                 i->f->set_signalling(shost, type);
 366
 367         return count;
 368 }
 369 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
 370                          show_spi_host_signalling,
 371                          store_spi_host_signalling);
 372
 373 #define DV_SET(x, y)                    \
 374         if(i->f->set_##x)               \
 375                 i->f->set_##x(sdev->sdev_target, y)
 376
 377 #define DV_LOOPS        3
 378 #define DV_TIMEOUT      (10*HZ)
 379 #define DV_RETRIES      3       /* should only need at most
 380                                  * two cc/ua clears */
 381
 382 enum spi_compare_returns {
 383         SPI_COMPARE_SUCCESS,
 384         SPI_COMPARE_FAILURE,
 385         SPI_COMPARE_SKIP_TEST,
 386 };
 387
 388
 389 /* This is for read/write Domain Validation:  If the device supports
 390  * an echo buffer, we do read/write tests to it */
 391 static enum spi_compare_returns
 392 spi_dv_device_echo_buffer(struct scsi_request *sreq, u8 *buffer,
 393                           u8 *ptr, const int retries)
 394 {
 395         struct scsi_device *sdev = sreq->sr_device;
 396         int len = ptr - buffer;
 397         int j, k, r;
 398         unsigned int pattern = 0x0000ffff;
 399
 400         const char spi_write_buffer[] = {
 401                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 402         };
 403         const char spi_read_buffer[] = {
 404                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 405         };
 406
 407         /* set up the pattern buffer.  Doesn't matter if we spill
 408          * slightly beyond since that's where the read buffer is */
 409         for (j = 0; j < len; ) {
 410
 411                 /* fill the buffer with counting (test a) */
 412                 for ( ; j < min(len, 32); j++)
 413                         buffer[j] = j;
 414                 k = j;
 415                 /* fill the buffer with alternating words of 0x0 and
 416                  * 0xffff (test b) */
 417                 for ( ; j < min(len, k + 32); j += 2) {
 418                         u16 *word = (u16 *)&buffer[j];
 419
 420                         *word = (j & 0x02) ? 0x0000 : 0xffff;
 421                 }
 422                 k = j;
 423                 /* fill with crosstalk (alternating 0x5555 0xaaa)
 424                  * (test c) */
 425                 for ( ; j < min(len, k + 32); j += 2) {
 426                         u16 *word = (u16 *)&buffer[j];
 427
 428                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
 429                 }
 430                 k = j;
 431                 /* fill with shifting bits (test d) */
 432                 for ( ; j < min(len, k + 32); j += 4) {
 433                         u32 *word = (unsigned int *)&buffer[j];
 434                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
 435
 436                         *word = pattern;
 437                         pattern = (pattern << 1) | roll;
 438                 }
 439                 /* don't bother with random data (test e) */
 440         }
 441
 442         for (r = 0; r < retries; r++) {
 443                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 444                 sreq->sr_data_direction = DMA_TO_DEVICE;
 445                 scsi_wait_req(sreq, spi_write_buffer, buffer, len,
 446                               DV_TIMEOUT, DV_RETRIES);
 447                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 448                         struct scsi_sense_hdr sshdr;
 449
 450                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 451                         if (scsi_request_normalize_sense(sreq, &sshdr)
 452                             && sshdr.sense_key == ILLEGAL_REQUEST
 453                             /* INVALID FIELD IN CDB */
 454                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
 455                                 /* This would mean that the drive lied
 456                                  * to us about supporting an echo
 457                                  * buffer (unfortunately some Western
 458                                  * Digital drives do precisely this)
 459                                  */
 460                                 return SPI_COMPARE_SKIP_TEST;
 461
 462
 463                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Write Buffer failure %x\n", sreq->sr_result);
 464                         return SPI_COMPARE_FAILURE;
 465                 }
 466
 467                 memset(ptr, 0, len);
 468                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 469                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 470                 scsi_wait_req(sreq, spi_read_buffer, ptr, len,
 471                               DV_TIMEOUT, DV_RETRIES);
 472                 scsi_device_set_state(sdev, SDEV_QUIESCE);
 473
 474                 if (memcmp(buffer, ptr, len) != 0)
 475                         return SPI_COMPARE_FAILURE;
 476         }
 477         return SPI_COMPARE_SUCCESS;
 478 }
 479
 480 /* This is for the simplest form of Domain Validation: a read test
 481  * on the inquiry data from the device */
 482 static enum spi_compare_returns
 483 spi_dv_device_compare_inquiry(struct scsi_request *sreq, u8 *buffer,
 484                               u8 *ptr, const int retries)
 485 {
 486         int r;
 487         const int len = sreq->sr_device->inquiry_len;
 488         struct scsi_device *sdev = sreq->sr_device;
 489         const char spi_inquiry[] = {
 490                 INQUIRY, 0, 0, 0, len, 0
 491         };
 492
 493         for (r = 0; r < retries; r++) {
 494                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 495                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 496
 497                 memset(ptr, 0, len);
 498
 499                 scsi_wait_req(sreq, spi_inquiry, ptr, len,
 500                               DV_TIMEOUT, DV_RETRIES);
 501
 502                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 503                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 504                         return SPI_COMPARE_FAILURE;
 505                 }
 506
 507                 /* If we don't have the inquiry data already, the
 508                  * first read gets it */
 509                 if (ptr == buffer) {
 510                         ptr += len;
 511                         --r;
 512                         continue;
 513                 }
 514
 515                 if (memcmp(buffer, ptr, len) != 0)
 516                         /* failure */
 517                         return SPI_COMPARE_FAILURE;
 518         }
 519         return SPI_COMPARE_SUCCESS;
 520 }
 521
 522 static enum spi_compare_returns
 523 spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
 524                enum spi_compare_returns
 525                (*compare_fn)(struct scsi_request *, u8 *, u8 *, int))
 526 {
 527         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 528         struct scsi_device *sdev = sreq->sr_device;
 529         int period = 0, prevperiod = 0;
 530         enum spi_compare_returns retval;
 531
 532
 533         for (;;) {
 534                 int newperiod;
 535                 retval = compare_fn(sreq, buffer, ptr, DV_LOOPS);
 536
 537                 if (retval == SPI_COMPARE_SUCCESS
 538                     || retval == SPI_COMPARE_SKIP_TEST)
 539                         break;
 540
 541                 /* OK, retrain, fallback */
 542                 if (i->f->get_period)
 543                         i->f->get_period(sdev->sdev_target);
 544                 newperiod = spi_period(sdev->sdev_target);
 545                 period = newperiod > period ? newperiod : period;
 546                 if (period < 0x0d)
 547                         period++;
 548                 else
 549                         period += period >> 1;
 550
 551                 if (unlikely(period > 0xff || period == prevperiod)) {
 552                         /* Total failure; set to async and return */
 553                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
 554                         DV_SET(offset, 0);
 555                         return SPI_COMPARE_FAILURE;
 556                 }
 557                 SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation detected failure, dropping back\n");
 558                 DV_SET(period, period);
 559                 prevperiod = period;
 560         }
 561         return retval;
 562 }
 563
 564 static int
 565 spi_dv_device_get_echo_buffer(struct scsi_request *sreq, u8 *buffer)
 566 {
 567         int l;
 568
 569         /* first off do a test unit ready.  This can error out
 570          * because of reservations or some other reason.  If it
 571          * fails, the device won't let us write to the echo buffer
 572          * so just return failure */
 573
 574         const char spi_test_unit_ready[] = {
 575                 TEST_UNIT_READY, 0, 0, 0, 0, 0
 576         };
 577
 578         const char spi_read_buffer_descriptor[] = {
 579                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
 580         };
 581
 582
 583         sreq->sr_cmd_len = 0;
 584         sreq->sr_data_direction = DMA_NONE;
 585
 586         /* We send a set of three TURs to clear any outstanding
 587          * unit attention conditions if they exist (Otherwise the
 588          * buffer tests won't be happy).  If the TUR still fails
 589          * (reservation conflict, device not ready, etc) just
 590          * skip the write tests */
 591         for (l = 0; ; l++) {
 592                 scsi_wait_req(sreq, spi_test_unit_ready, NULL, 0,
 593                               DV_TIMEOUT, DV_RETRIES);
 594
 595                 if(sreq->sr_result) {
 596                         if(l >= 3)
 597                                 return 0;
 598                 } else {
 599                         /* TUR succeeded */
 600                         break;
 601                 }
 602         }
 603
 604         sreq->sr_cmd_len = 0;
 605         sreq->sr_data_direction = DMA_FROM_DEVICE;
 606
 607         scsi_wait_req(sreq, spi_read_buffer_descriptor, buffer, 4,
 608                       DV_TIMEOUT, DV_RETRIES);
 609
 610         if (sreq->sr_result)
 611                 /* Device has no echo buffer */
 612                 return 0;
 613
 614         return buffer[3] + ((buffer[2] & 0x1f) << 8);
 615 }
 616
 617 static void
 618 spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
 619 {
 620         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 621         struct scsi_device *sdev = sreq->sr_device;
 622         int len = sdev->inquiry_len;
 623         /* first set us up for narrow async */
 624         DV_SET(offset, 0);
 625         DV_SET(width, 0);
 626
 627         if (spi_dv_device_compare_inquiry(sreq, buffer, buffer, DV_LOOPS)
 628             != SPI_COMPARE_SUCCESS) {
 629                 SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
 630                 /* FIXME: should probably offline the device here? */
 631                 return;
 632         }
 633
 634         /* test width */
 635         if (i->f->set_width && sdev->wdtr) {
 636                 i->f->set_width(sdev->sdev_target, 1);
 637
 638                 if (spi_dv_device_compare_inquiry(sreq, buffer,
 639                                                    buffer + len,
 640                                                    DV_LOOPS)
 641                     != SPI_COMPARE_SUCCESS) {
 642                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Wide Transfers Fail\n");
 643                         i->f->set_width(sdev->sdev_target, 0);
 644                 }
 645         }
 646
 647         if (!i->f->set_period)
 648                 return;
 649
 650         /* device can't handle synchronous */
 651         if(!sdev->ppr && !sdev->sdtr)
 652                 return;
 653
 654         /* see if the device has an echo buffer.  If it does we can
 655          * do the SPI pattern write tests */
 656
 657         len = 0;
 658         if (sdev->ppr)
 659                 len = spi_dv_device_get_echo_buffer(sreq, buffer);
 660
 661  retry:
 662
 663         /* now set up to the maximum */
 664         DV_SET(offset, 255);
 665         DV_SET(period, 1);
 666
 667         if (len == 0) {
 668                 SPI_PRINTK(sdev->sdev_target, KERN_INFO, "Domain Validation skipping write tests\n");
 669                 spi_dv_retrain(sreq, buffer, buffer + len,
 670                                spi_dv_device_compare_inquiry);
 671                 return;
 672         }
 673
 674         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
 675                 SPI_PRINTK(sdev->sdev_target, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
 676                 len = SPI_MAX_ECHO_BUFFER_SIZE;
 677         }
 678
 679         if (spi_dv_retrain(sreq, buffer, buffer + len,
 680                            spi_dv_device_echo_buffer)
 681             == SPI_COMPARE_SKIP_TEST) {
 682                 /* OK, the stupid drive can't do a write echo buffer
 683                  * test after all, fall back to the read tests */
 684                 len = 0;
 685                 goto retry;
 686         }
 687 }
 688
 689
 690 /**     spi_dv_device - Do Domain Validation on the device
 691  *      @sdev:          scsi device to validate
 692  *
 693  *      Performs the domain validation on the given device in the
 694  *      current execution thread.  Since DV operations may sleep,
 695  *      the current thread must have user context.  Also no SCSI
 696  *      related locks that would deadlock I/O issued by the DV may
 697  *      be held.
 698  */
 699 void
 700 spi_dv_device(struct scsi_device *sdev)
 701 {
 702         struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL);
 703         struct scsi_target *starget = sdev->sdev_target;
 704         u8 *buffer;
 705         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
 706
 707         if (unlikely(!sreq))
 708                 return;
 709
 710         if (unlikely(scsi_device_get(sdev)))
 711                 goto out_free_req;
 712
 713         buffer = kmalloc(len, GFP_KERNEL);
 714
 715         if (unlikely(!buffer))
 716                 goto out_put;
 717
 718         memset(buffer, 0, len);
 719
 720         /* We need to verify that the actual device will quiesce; the
 721          * later target quiesce is just a nice to have */
 722         if (unlikely(scsi_device_quiesce(sdev)))
 723                 goto out_free;
 724
 725         scsi_target_quiesce(starget);
 726
 727         spi_dv_pending(starget) = 1;
 728         down(&spi_dv_sem(starget));
 729
 730         SPI_PRINTK(starget, KERN_INFO, "Beginning Domain Validation\n");
 731
 732         spi_dv_device_internal(sreq, buffer);
 733
 734         SPI_PRINTK(starget, KERN_INFO, "Ending Domain Validation\n");
 735
 736         up(&spi_dv_sem(starget));
 737         spi_dv_pending(starget) = 0;
 738
 739         scsi_target_resume(starget);
 740
 741         spi_initial_dv(starget) = 1;
 742
 743  out_free:
 744         kfree(buffer);
 745  out_put:
 746         scsi_device_put(sdev);
 747  out_free_req:
 748         scsi_release_request(sreq);
 749 }
 750 EXPORT_SYMBOL(spi_dv_device);
 751
 752 struct work_queue_wrapper {
 753         struct work_struct      work;
 754         struct scsi_device      *sdev;
 755 };
 756
 757 static void
 758 spi_dv_device_work_wrapper(void *data)
 759 {
 760         struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
 761         struct scsi_device *sdev = wqw->sdev;
 762
 763         kfree(wqw);
 764         spi_dv_device(sdev);
 765         spi_dv_pending(sdev->sdev_target) = 0;
 766         scsi_device_put(sdev);
 767 }
 768
 769
 770 /**
 771  *      spi_schedule_dv_device - schedule domain validation to occur on the device
 772  *      @sdev:  The device to validate
 773  *
 774  *      Identical to spi_dv_device() above, except that the DV will be
 775  *      scheduled to occur in a workqueue later.  All memory allocations
 776  *      are atomic, so may be called from any context including those holding
 777  *      SCSI locks.
 778  */
 779 void
 780 spi_schedule_dv_device(struct scsi_device *sdev)
 781 {
 782         struct work_queue_wrapper *wqw =
 783                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
 784
 785         if (unlikely(!wqw))
 786                 return;
 787
 788         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
 789                 kfree(wqw);
 790                 return;
 791         }
 792         /* Set pending early (dv_device doesn't check it, only sets it) */
 793         spi_dv_pending(sdev->sdev_target) = 1;
 794         if (unlikely(scsi_device_get(sdev))) {
 795                 kfree(wqw);
 796                 spi_dv_pending(sdev->sdev_target) = 0;
 797                 return;
 798         }
 799
 800         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
 801         wqw->sdev = sdev;
 802
 803         schedule_work(&wqw->work);
 804 }
 805 EXPORT_SYMBOL(spi_schedule_dv_device);
 806
 807 #define SETUP_ATTRIBUTE(field)                                          \
 808         i->private_attrs[count] = class_device_attr_##field;            \
 809         if (!i->f->set_##field) {                                       \
 810                 i->private_attrs[count].attr.mode = S_IRUGO;            \
 811                 i->private_attrs[count].store = NULL;                   \
 812         }                                                               \
 813         i->attrs[count] = &i->private_attrs[count];                     \
 814         if (i->f->show_##field)                                         \
 815                 count++
 816
 817 #define SETUP_HOST_ATTRIBUTE(field)                                     \
 818         i->private_host_attrs[count] = class_device_attr_##field;       \
 819         if (!i->f->set_##field) {                                       \
 820                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
 821                 i->private_host_attrs[count].store = NULL;              \
 822         }                                                               \
 823         i->host_attrs[count] = &i->private_host_attrs[count];           \
 824         count++
 825
 826 struct scsi_transport_template *
 827 spi_attach_transport(struct spi_function_template *ft)
 828 {
 829         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
 830                                          GFP_KERNEL);
 831         int count = 0;
 832         if (unlikely(!i))
 833                 return NULL;
 834
 835         memset(i, 0, sizeof(struct spi_internal));
 836
 837
 838         i->t.target_attrs = &i->attrs[0];
 839         i->t.target_class = &spi_transport_class;
 840         i->t.target_setup = &spi_setup_transport_attrs;
 841         i->t.device_configure = &spi_configure_device;
 842         i->t.target_size = sizeof(struct spi_transport_attrs);
 843         i->t.host_attrs = &i->host_attrs[0];
 844         i->t.host_class = &spi_host_class;
 845         i->t.host_setup = &spi_setup_host_attrs;
 846         i->t.host_size = sizeof(struct spi_host_attrs);
 847         i->f = ft;
 848
 849         SETUP_ATTRIBUTE(period);
 850         SETUP_ATTRIBUTE(offset);
 851         SETUP_ATTRIBUTE(width);
 852         SETUP_ATTRIBUTE(iu);
 853         SETUP_ATTRIBUTE(dt);
 854         SETUP_ATTRIBUTE(qas);
 855         SETUP_ATTRIBUTE(wr_flow);
 856         SETUP_ATTRIBUTE(rd_strm);
 857         SETUP_ATTRIBUTE(rti);
 858         SETUP_ATTRIBUTE(pcomp_en);
 859
 860         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
 861          * this bug will trigger */
 862         BUG_ON(count > SPI_NUM_ATTRS);
 863
 864         i->attrs[count++] = &class_device_attr_revalidate;
 865
 866         i->attrs[count] = NULL;
 867
 868         count = 0;
 869         SETUP_HOST_ATTRIBUTE(signalling);
 870
 871         BUG_ON(count > SPI_HOST_ATTRS);
 872
 873         i->host_attrs[count] = NULL;
 874
 875         return &i->t;
 876 }
 877 EXPORT_SYMBOL(spi_attach_transport);
 878
 879 void spi_release_transport(struct scsi_transport_template *t)
 880 {
 881         struct spi_internal *i = to_spi_internal(t);
 882
 883         kfree(i);
 884 }
 885 EXPORT_SYMBOL(spi_release_transport);
 886
 887
 888 MODULE_AUTHOR("Martin Hicks");
 889 MODULE_DESCRIPTION("SPI Transport Attributes");
 890 MODULE_LICENSE("GPL");
 891
 892 module_init(spi_transport_init);
 893 module_exit(spi_transport_exit);