drivers/ide/ide-atapi.c

   1 /*
   2  * ATAPI support.
   3  */
   4
   5 #include <linux/kernel.h>
   6 #include <linux/cdrom.h>
   7 #include <linux/delay.h>
   8 #include <linux/ide.h>
   9 #include <linux/scatterlist.h>
  10
  11 #include <scsi/scsi.h>
  12
  13 #define DRV_NAME "ide-atapi"
  14 #define PFX DRV_NAME ": "
  15
  16 #ifdef DEBUG
  17 #define debug_log(fmt, args...) \
  18         printk(KERN_INFO "ide: " fmt, ## args)
  19 #else
  20 #define debug_log(fmt, args...) do {} while (0)
  21 #endif
  22
  23 #define ATAPI_MIN_CDB_BYTES     12
  24
  25 static inline int dev_is_idecd(ide_drive_t *drive)
  26 {
  27         return drive->media == ide_cdrom || drive->media == ide_optical;
  28 }
  29
  30 /*
  31  * Check whether we can support a device,
  32  * based on the ATAPI IDENTIFY command results.
  33  */
  34 int ide_check_atapi_device(ide_drive_t *drive, const char *s)
  35 {
  36         u16 *id = drive->id;
  37         u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
  38
  39         *((u16 *)&gcw) = id[ATA_ID_CONFIG];
  40
  41         protocol    = (gcw[1] & 0xC0) >> 6;
  42         device_type =  gcw[1] & 0x1F;
  43         removable   = (gcw[0] & 0x80) >> 7;
  44         drq_type    = (gcw[0] & 0x60) >> 5;
  45         packet_size =  gcw[0] & 0x03;
  46
  47 #ifdef CONFIG_PPC
  48         /* kludge for Apple PowerBook internal zip */
  49         if (drive->media == ide_floppy && device_type == 5 &&
  50             !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
  51             strstr((char *)&id[ATA_ID_PROD], "ZIP"))
  52                 device_type = 0;
  53 #endif
  54
  55         if (protocol != 2)
  56                 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
  57                         s, drive->name, protocol);
  58         else if ((drive->media == ide_floppy && device_type != 0) ||
  59                  (drive->media == ide_tape && device_type != 1))
  60                 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
  61                         s, drive->name, device_type);
  62         else if (removable == 0)
  63                 printk(KERN_ERR "%s: %s: the removable flag is not set\n",
  64                         s, drive->name);
  65         else if (drive->media == ide_floppy && drq_type == 3)
  66                 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
  67                         "supported\n", s, drive->name, drq_type);
  68         else if (packet_size != 0)
  69                 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
  70                         "bytes\n", s, drive->name, packet_size);
  71         else
  72                 return 1;
  73         return 0;
  74 }
  75 EXPORT_SYMBOL_GPL(ide_check_atapi_device);
  76
  77 void ide_init_pc(struct ide_atapi_pc *pc)
  78 {
  79         memset(pc, 0, sizeof(*pc));
  80 }
  81 EXPORT_SYMBOL_GPL(ide_init_pc);
  82
  83 /*
  84  * Add a special packet command request to the tail of the request queue,
  85  * and wait for it to be serviced.
  86  */
  87 int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
  88                       struct ide_atapi_pc *pc, void *buf, unsigned int bufflen)
  89 {
  90         struct request *rq;
  91         int error;
  92
  93         rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
  94         rq->cmd_type = REQ_TYPE_SPECIAL;
  95         rq->special = (char *)pc;
  96
  97         if (buf && bufflen) {
  98                 error = blk_rq_map_kern(drive->queue, rq, buf, bufflen,
  99                                         GFP_NOIO);
 100                 if (error)
 101                         goto put_req;
 102         }
 103
 104         memcpy(rq->cmd, pc->c, 12);
 105         if (drive->media == ide_tape)
 106                 rq->cmd[13] = REQ_IDETAPE_PC1;
 107         error = blk_execute_rq(drive->queue, disk, rq, 0);
 108 put_req:
 109         blk_put_request(rq);
 110         return error;
 111 }
 112 EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
 113
 114 int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
 115 {
 116         struct ide_atapi_pc pc;
 117
 118         ide_init_pc(&pc);
 119         pc.c[0] = TEST_UNIT_READY;
 120
 121         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
 122 }
 123 EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
 124
 125 int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
 126 {
 127         struct ide_atapi_pc pc;
 128
 129         ide_init_pc(&pc);
 130         pc.c[0] = START_STOP;
 131         pc.c[4] = start;
 132
 133         if (drive->media == ide_tape)
 134                 pc.flags |= PC_FLAG_WAIT_FOR_DSC;
 135
 136         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
 137 }
 138 EXPORT_SYMBOL_GPL(ide_do_start_stop);
 139
 140 int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
 141 {
 142         struct ide_atapi_pc pc;
 143
 144         if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
 145                 return 0;
 146
 147         ide_init_pc(&pc);
 148         pc.c[0] = ALLOW_MEDIUM_REMOVAL;
 149         pc.c[4] = on;
 150
 151         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
 152 }
 153 EXPORT_SYMBOL_GPL(ide_set_media_lock);
 154
 155 void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
 156 {
 157         ide_init_pc(pc);
 158         pc->c[0] = REQUEST_SENSE;
 159         if (drive->media == ide_floppy) {
 160                 pc->c[4] = 255;
 161                 pc->req_xfer = 18;
 162         } else {
 163                 pc->c[4] = 20;
 164                 pc->req_xfer = 20;
 165         }
 166 }
 167 EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
 168
 169 void ide_prep_sense(ide_drive_t *drive, struct request *rq)
 170 {
 171         struct request_sense *sense = &drive->sense_data;
 172         struct request *sense_rq = &drive->sense_rq;
 173         unsigned int cmd_len, sense_len;
 174         int err;
 175
 176         switch (drive->media) {
 177         case ide_floppy:
 178                 cmd_len = 255;
 179                 sense_len = 18;
 180                 break;
 181         case ide_tape:
 182                 cmd_len = 20;
 183                 sense_len = 20;
 184                 break;
 185         default:
 186                 cmd_len = 18;
 187                 sense_len = 18;
 188         }
 189
 190         BUG_ON(sense_len > sizeof(*sense));
 191
 192         if (blk_sense_request(rq) || drive->sense_rq_armed)
 193                 return;
 194
 195         memset(sense, 0, sizeof(*sense));
 196
 197         blk_rq_init(rq->q, sense_rq);
 198
 199         err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
 200                               GFP_NOIO);
 201         if (unlikely(err)) {
 202                 if (printk_ratelimit())
 203                         printk(KERN_WARNING PFX "%s: failed to map sense "
 204                                             "buffer\n", drive->name);
 205                 return;
 206         }
 207
 208         sense_rq->rq_disk = rq->rq_disk;
 209         sense_rq->cmd[0] = GPCMD_REQUEST_SENSE;
 210         sense_rq->cmd[4] = cmd_len;
 211         sense_rq->cmd_type = REQ_TYPE_SENSE;
 212         sense_rq->cmd_flags |= REQ_PREEMPT;
 213
 214         if (drive->media == ide_tape)
 215                 sense_rq->cmd[13] = REQ_IDETAPE_PC1;
 216
 217         drive->sense_rq_armed = true;
 218 }
 219 EXPORT_SYMBOL_GPL(ide_prep_sense);
 220
 221 int ide_queue_sense_rq(ide_drive_t *drive, void *special)
 222 {
 223         /* deferred failure from ide_prep_sense() */
 224         if (!drive->sense_rq_armed) {
 225                 printk(KERN_WARNING PFX "%s: error queuing a sense request\n",
 226                        drive->name);
 227                 return -ENOMEM;
 228         }
 229
 230         drive->sense_rq.special = special;
 231         drive->sense_rq_armed = false;
 232
 233         drive->hwif->rq = NULL;
 234
 235         elv_add_request(drive->queue, &drive->sense_rq,
 236                         ELEVATOR_INSERT_FRONT, 0);
 237         return 0;
 238 }
 239 EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
 240
 241 /*
 242  * Called when an error was detected during the last packet command.
 243  * We queue a request sense packet command at the head of the request
 244  * queue.
 245  */
 246 void ide_retry_pc(ide_drive_t *drive)
 247 {
 248         struct request *failed_rq = drive->hwif->rq;
 249         struct request *sense_rq = &drive->sense_rq;
 250         struct ide_atapi_pc *pc = &drive->request_sense_pc;
 251
 252         (void)ide_read_error(drive);
 253
 254         /* init pc from sense_rq */
 255         ide_init_pc(pc);
 256         memcpy(pc->c, sense_rq->cmd, 12);
 257
 258         if (drive->media == ide_tape)
 259                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
 260
 261         /*
 262          * Push back the failed request and put request sense on top
 263          * of it.  The failed command will be retried after sense data
 264          * is acquired.
 265          */
 266         blk_requeue_request(failed_rq->q, failed_rq);
 267         drive->hwif->rq = NULL;
 268         if (ide_queue_sense_rq(drive, pc)) {
 269                 blk_start_request(failed_rq);
 270                 ide_complete_rq(drive, -EIO, blk_rq_bytes(failed_rq));
 271         }
 272 }
 273 EXPORT_SYMBOL_GPL(ide_retry_pc);
 274
 275 int ide_cd_expiry(ide_drive_t *drive)
 276 {
 277         struct request *rq = drive->hwif->rq;
 278         unsigned long wait = 0;
 279
 280         debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]);
 281
 282         /*
 283          * Some commands are *slow* and normally take a long time to complete.
 284          * Usually we can use the ATAPI "disconnect" to bypass this, but not all
 285          * commands/drives support that. Let ide_timer_expiry keep polling us
 286          * for these.
 287          */
 288         switch (rq->cmd[0]) {
 289         case GPCMD_BLANK:
 290         case GPCMD_FORMAT_UNIT:
 291         case GPCMD_RESERVE_RZONE_TRACK:
 292         case GPCMD_CLOSE_TRACK:
 293         case GPCMD_FLUSH_CACHE:
 294                 wait = ATAPI_WAIT_PC;
 295                 break;
 296         default:
 297                 if (!(rq->cmd_flags & REQ_QUIET))
 298                         printk(KERN_INFO PFX "cmd 0x%x timed out\n",
 299                                          rq->cmd[0]);
 300                 wait = 0;
 301                 break;
 302         }
 303         return wait;
 304 }
 305 EXPORT_SYMBOL_GPL(ide_cd_expiry);
 306
 307 int ide_cd_get_xferlen(struct request *rq)
 308 {
 309         if (blk_fs_request(rq))
 310                 return 32768;
 311         else if (blk_sense_request(rq) || blk_pc_request(rq) ||
 312                          rq->cmd_type == REQ_TYPE_ATA_PC)
 313                 return blk_rq_bytes(rq);
 314         else
 315                 return 0;
 316 }
 317 EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
 318
 319 void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
 320 {
 321         struct ide_taskfile tf;
 322
 323         drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT |
 324                                      IDE_VALID_LBAM | IDE_VALID_LBAH);
 325
 326         *bcount = (tf.lbah << 8) | tf.lbam;
 327         *ireason = tf.nsect & 3;
 328 }
 329 EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
 330
 331 /*
 332  * Check the contents of the interrupt reason register and attempt to recover if
 333  * there are problems.
 334  *
 335  * Returns:
 336  * - 0 if everything's ok
 337  * - 1 if the request has to be terminated.
 338  */
 339 int ide_check_ireason(ide_drive_t *drive, struct request *rq, int len,
 340                       int ireason, int rw)
 341 {
 342         ide_hwif_t *hwif = drive->hwif;
 343
 344         debug_log("ireason: 0x%x, rw: 0x%x\n", ireason, rw);
 345
 346         if (ireason == (!rw << 1))
 347                 return 0;
 348         else if (ireason == (rw << 1)) {
 349                 printk(KERN_ERR PFX "%s: %s: wrong transfer direction!\n",
 350                                 drive->name, __func__);
 351
 352                 if (dev_is_idecd(drive))
 353                         ide_pad_transfer(drive, rw, len);
 354         } else if (!rw && ireason == ATAPI_COD) {
 355                 if (dev_is_idecd(drive)) {
 356                         /*
 357                          * Some drives (ASUS) seem to tell us that status info
 358                          * is available.  Just get it and ignore.
 359                          */
 360                         (void)hwif->tp_ops->read_status(hwif);
 361                         return 0;
 362                 }
 363         } else {
 364                 if (ireason & ATAPI_COD)
 365                         printk(KERN_ERR PFX "%s: CoD != 0 in %s\n", drive->name,
 366                                         __func__);
 367
 368                 /* drive wants a command packet, or invalid ireason... */
 369                 printk(KERN_ERR PFX "%s: %s: bad interrupt reason 0x%02x\n",
 370                                 drive->name, __func__, ireason);
 371         }
 372
 373         if (dev_is_idecd(drive) && rq->cmd_type == REQ_TYPE_ATA_PC)
 374                 rq->cmd_flags |= REQ_FAILED;
 375
 376         return 1;
 377 }
 378 EXPORT_SYMBOL_GPL(ide_check_ireason);
 379
 380 /*
 381  * This is the usual interrupt handler which will be called during a packet
 382  * command.  We will transfer some of the data (as requested by the drive)
 383  * and will re-point interrupt handler to us.
 384  */
 385 static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
 386 {
 387         struct ide_atapi_pc *pc = drive->pc;
 388         ide_hwif_t *hwif = drive->hwif;
 389         struct ide_cmd *cmd = &hwif->cmd;
 390         struct request *rq = hwif->rq;
 391         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
 392         unsigned int timeout, done;
 393         u16 bcount;
 394         u8 stat, ireason, dsc = 0;
 395         u8 write = !!(pc->flags & PC_FLAG_WRITING);
 396
 397         debug_log("Enter %s - interrupt handler\n", __func__);
 398
 399         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 400                                                : WAIT_TAPE_CMD;
 401
 402         /* Clear the interrupt */
 403         stat = tp_ops->read_status(hwif);
 404
 405         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 406                 int rc;
 407
 408                 drive->waiting_for_dma = 0;
 409                 rc = hwif->dma_ops->dma_end(drive);
 410                 ide_dma_unmap_sg(drive, cmd);
 411
 412                 if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
 413                         if (drive->media == ide_floppy)
 414                                 printk(KERN_ERR PFX "%s: DMA %s error\n",
 415                                         drive->name, rq_data_dir(pc->rq)
 416                                                      ? "write" : "read");
 417                         pc->flags |= PC_FLAG_DMA_ERROR;
 418                 } else
 419                         rq->resid_len = 0;
 420                 debug_log("%s: DMA finished\n", drive->name);
 421         }
 422
 423         /* No more interrupts */
 424         if ((stat & ATA_DRQ) == 0) {
 425                 int uptodate, error;
 426
 427                 debug_log("Packet command completed, %d bytes transferred\n",
 428                           blk_rq_bytes(rq));
 429
 430                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 431
 432                 local_irq_enable_in_hardirq();
 433
 434                 if (drive->media == ide_tape &&
 435                     (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
 436                         stat &= ~ATA_ERR;
 437
 438                 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
 439                         /* Error detected */
 440                         debug_log("%s: I/O error\n", drive->name);
 441
 442                         if (drive->media != ide_tape)
 443                                 pc->rq->errors++;
 444
 445                         if (rq->cmd[0] == REQUEST_SENSE) {
 446                                 printk(KERN_ERR PFX "%s: I/O error in request "
 447                                                 "sense command\n", drive->name);
 448                                 return ide_do_reset(drive);
 449                         }
 450
 451                         debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
 452
 453                         /* Retry operation */
 454                         ide_retry_pc(drive);
 455
 456                         /* queued, but not started */
 457                         return ide_stopped;
 458                 }
 459                 pc->error = 0;
 460
 461                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
 462                         dsc = 1;
 463
 464                 /*
 465                  * ->pc_callback() might change rq->data_len for
 466                  * residual count, cache total length.
 467                  */
 468                 done = blk_rq_bytes(rq);
 469
 470                 /* Command finished - Call the callback function */
 471                 uptodate = drive->pc_callback(drive, dsc);
 472
 473                 if (uptodate == 0)
 474                         drive->failed_pc = NULL;
 475
 476                 if (blk_special_request(rq)) {
 477                         rq->errors = 0;
 478                         error = 0;
 479                 } else {
 480
 481                         if (blk_fs_request(rq) == 0 && uptodate <= 0) {
 482                                 if (rq->errors == 0)
 483                                         rq->errors = -EIO;
 484                         }
 485
 486                         error = uptodate ? 0 : -EIO;
 487                 }
 488
 489                 ide_complete_rq(drive, error, blk_rq_bytes(rq));
 490                 return ide_stopped;
 491         }
 492
 493         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 494                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 495                 printk(KERN_ERR PFX "%s: The device wants to issue more "
 496                                 "interrupts in DMA mode\n", drive->name);
 497                 ide_dma_off(drive);
 498                 return ide_do_reset(drive);
 499         }
 500
 501         /* Get the number of bytes to transfer on this interrupt. */
 502         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
 503
 504         if (ide_check_ireason(drive, rq, bcount, ireason, write))
 505                 return ide_do_reset(drive);
 506
 507         done = min_t(unsigned int, bcount, cmd->nleft);
 508         ide_pio_bytes(drive, cmd, write, done);
 509
 510         /* Update transferred byte count */
 511         rq->resid_len -= done;
 512
 513         bcount -= done;
 514
 515         if (bcount)
 516                 ide_pad_transfer(drive, write, bcount);
 517
 518         debug_log("[cmd %x] transferred %d bytes, padded %d bytes, resid: %u\n",
 519                   rq->cmd[0], done, bcount, rq->resid_len);
 520
 521         /* And set the interrupt handler again */
 522         ide_set_handler(drive, ide_pc_intr, timeout);
 523         return ide_started;
 524 }
 525
 526 static void ide_init_packet_cmd(struct ide_cmd *cmd, u8 valid_tf,
 527                                 u16 bcount, u8 dma)
 528 {
 529         cmd->protocol = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
 530         cmd->valid.out.tf = IDE_VALID_LBAH | IDE_VALID_LBAM |
 531                             IDE_VALID_FEATURE | valid_tf;
 532         cmd->tf.command = ATA_CMD_PACKET;
 533         cmd->tf.feature = dma;          /* Use PIO/DMA */
 534         cmd->tf.lbam    = bcount & 0xff;
 535         cmd->tf.lbah    = (bcount >> 8) & 0xff;
 536 }
 537
 538 static u8 ide_read_ireason(ide_drive_t *drive)
 539 {
 540         struct ide_taskfile tf;
 541
 542         drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT);
 543
 544         return tf.nsect & 3;
 545 }
 546
 547 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
 548 {
 549         int retries = 100;
 550
 551         while (retries-- && ((ireason & ATAPI_COD) == 0 ||
 552                 (ireason & ATAPI_IO))) {
 553                 printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing "
 554                                 "a packet command, retrying\n", drive->name);
 555                 udelay(100);
 556                 ireason = ide_read_ireason(drive);
 557                 if (retries == 0) {
 558                         printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing"
 559                                         " a packet command, ignoring\n",
 560                                         drive->name);
 561                         ireason |= ATAPI_COD;
 562                         ireason &= ~ATAPI_IO;
 563                 }
 564         }
 565
 566         return ireason;
 567 }
 568
 569 static int ide_delayed_transfer_pc(ide_drive_t *drive)
 570 {
 571         /* Send the actual packet */
 572         drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
 573
 574         /* Timeout for the packet command */
 575         return WAIT_FLOPPY_CMD;
 576 }
 577
 578 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
 579 {
 580         struct ide_atapi_pc *uninitialized_var(pc);
 581         ide_hwif_t *hwif = drive->hwif;
 582         struct request *rq = hwif->rq;
 583         ide_expiry_t *expiry;
 584         unsigned int timeout;
 585         int cmd_len;
 586         ide_startstop_t startstop;
 587         u8 ireason;
 588
 589         if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
 590                 printk(KERN_ERR PFX "%s: Strange, packet command initiated yet "
 591                                 "DRQ isn't asserted\n", drive->name);
 592                 return startstop;
 593         }
 594
 595         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
 596                 if (drive->dma)
 597                         drive->waiting_for_dma = 1;
 598         }
 599
 600         if (dev_is_idecd(drive)) {
 601                 /* ATAPI commands get padded out to 12 bytes minimum */
 602                 cmd_len = COMMAND_SIZE(rq->cmd[0]);
 603                 if (cmd_len < ATAPI_MIN_CDB_BYTES)
 604                         cmd_len = ATAPI_MIN_CDB_BYTES;
 605
 606                 timeout = rq->timeout;
 607                 expiry  = ide_cd_expiry;
 608         } else {
 609                 pc = drive->pc;
 610
 611                 cmd_len = ATAPI_MIN_CDB_BYTES;
 612
 613                 /*
 614                  * If necessary schedule the packet transfer to occur 'timeout'
 615                  * milliseconds later in ide_delayed_transfer_pc() after the
 616                  * device says it's ready for a packet.
 617                  */
 618                 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
 619                         timeout = drive->pc_delay;
 620                         expiry = &ide_delayed_transfer_pc;
 621                 } else {
 622                         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 623                                                                : WAIT_TAPE_CMD;
 624                         expiry = NULL;
 625                 }
 626
 627                 ireason = ide_read_ireason(drive);
 628                 if (drive->media == ide_tape)
 629                         ireason = ide_wait_ireason(drive, ireason);
 630
 631                 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
 632                         printk(KERN_ERR PFX "%s: (IO,CoD) != (0,1) while "
 633                                 "issuing a packet command\n", drive->name);
 634
 635                         return ide_do_reset(drive);
 636                 }
 637         }
 638
 639         hwif->expiry = expiry;
 640
 641         /* Set the interrupt routine */
 642         ide_set_handler(drive,
 643                         (dev_is_idecd(drive) ? drive->irq_handler
 644                                              : ide_pc_intr),
 645                         timeout);
 646
 647         /* Send the actual packet */
 648         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
 649                 hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
 650
 651         /* Begin DMA, if necessary */
 652         if (dev_is_idecd(drive)) {
 653                 if (drive->dma)
 654                         hwif->dma_ops->dma_start(drive);
 655         } else {
 656                 if (pc->flags & PC_FLAG_DMA_OK) {
 657                         pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
 658                         hwif->dma_ops->dma_start(drive);
 659                 }
 660         }
 661
 662         return ide_started;
 663 }
 664
 665 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
 666 {
 667         struct ide_atapi_pc *pc;
 668         ide_hwif_t *hwif = drive->hwif;
 669         ide_expiry_t *expiry = NULL;
 670         struct request *rq = hwif->rq;
 671         unsigned int timeout, bytes;
 672         u16 bcount;
 673         u8 valid_tf;
 674         u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
 675
 676         if (dev_is_idecd(drive)) {
 677                 valid_tf = IDE_VALID_NSECT | IDE_VALID_LBAL;
 678                 bcount = ide_cd_get_xferlen(rq);
 679                 expiry = ide_cd_expiry;
 680                 timeout = ATAPI_WAIT_PC;
 681
 682                 if (drive->dma)
 683                         drive->dma = !ide_dma_prepare(drive, cmd);
 684         } else {
 685                 pc = drive->pc;
 686
 687                 valid_tf = IDE_VALID_DEVICE;
 688                 bytes = blk_rq_bytes(rq);
 689                 bcount = ((drive->media == ide_tape) ? bytes
 690                                                      : min_t(unsigned int,
 691                                                              bytes, 63 * 1024));
 692
 693                 /* We haven't transferred any data yet */
 694                 rq->resid_len = bcount;
 695
 696                 if (pc->flags & PC_FLAG_DMA_ERROR) {
 697                         pc->flags &= ~PC_FLAG_DMA_ERROR;
 698                         ide_dma_off(drive);
 699                 }
 700
 701                 if (pc->flags & PC_FLAG_DMA_OK)
 702                         drive->dma = !ide_dma_prepare(drive, cmd);
 703
 704                 if (!drive->dma)
 705                         pc->flags &= ~PC_FLAG_DMA_OK;
 706
 707                 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 708                                                        : WAIT_TAPE_CMD;
 709         }
 710
 711         ide_init_packet_cmd(cmd, valid_tf, bcount, drive->dma);
 712
 713         (void)do_rw_taskfile(drive, cmd);
 714
 715         if (drq_int) {
 716                 if (drive->dma)
 717                         drive->waiting_for_dma = 0;
 718                 hwif->expiry = expiry;
 719         }
 720
 721         ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
 722
 723         return drq_int ? ide_started : ide_transfer_pc(drive);
 724 }
 725 EXPORT_SYMBOL_GPL(ide_issue_pc);