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 #ifdef DEBUG
  14 #define debug_log(fmt, args...) \
  15         printk(KERN_INFO "ide: " fmt, ## args)
  16 #else
  17 #define debug_log(fmt, args...) do {} while (0)
  18 #endif
  19
  20 #define ATAPI_MIN_CDB_BYTES     12
  21
  22 static inline int dev_is_idecd(ide_drive_t *drive)
  23 {
  24         return drive->media == ide_cdrom || drive->media == ide_optical;
  25 }
  26
  27 /*
  28  * Check whether we can support a device,
  29  * based on the ATAPI IDENTIFY command results.
  30  */
  31 int ide_check_atapi_device(ide_drive_t *drive, const char *s)
  32 {
  33         u16 *id = drive->id;
  34         u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
  35
  36         *((u16 *)&gcw) = id[ATA_ID_CONFIG];
  37
  38         protocol    = (gcw[1] & 0xC0) >> 6;
  39         device_type =  gcw[1] & 0x1F;
  40         removable   = (gcw[0] & 0x80) >> 7;
  41         drq_type    = (gcw[0] & 0x60) >> 5;
  42         packet_size =  gcw[0] & 0x03;
  43
  44 #ifdef CONFIG_PPC
  45         /* kludge for Apple PowerBook internal zip */
  46         if (drive->media == ide_floppy && device_type == 5 &&
  47             !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
  48             strstr((char *)&id[ATA_ID_PROD], "ZIP"))
  49                 device_type = 0;
  50 #endif
  51
  52         if (protocol != 2)
  53                 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
  54                         s, drive->name, protocol);
  55         else if ((drive->media == ide_floppy && device_type != 0) ||
  56                  (drive->media == ide_tape && device_type != 1))
  57                 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
  58                         s, drive->name, device_type);
  59         else if (removable == 0)
  60                 printk(KERN_ERR "%s: %s: the removable flag is not set\n",
  61                         s, drive->name);
  62         else if (drive->media == ide_floppy && drq_type == 3)
  63                 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
  64                         "supported\n", s, drive->name, drq_type);
  65         else if (packet_size != 0)
  66                 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
  67                         "bytes\n", s, drive->name, packet_size);
  68         else
  69                 return 1;
  70         return 0;
  71 }
  72 EXPORT_SYMBOL_GPL(ide_check_atapi_device);
  73
  74 /* PIO data transfer routine using the scatter gather table. */
  75 int ide_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
  76                     unsigned int bcount, int write)
  77 {
  78         ide_hwif_t *hwif = drive->hwif;
  79         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
  80         xfer_func_t *xf = write ? tp_ops->output_data : tp_ops->input_data;
  81         struct scatterlist *sg = pc->sg;
  82         char *buf;
  83         int count, done = 0;
  84
  85         while (bcount) {
  86                 count = min(sg->length - pc->b_count, bcount);
  87
  88                 if (PageHighMem(sg_page(sg))) {
  89                         unsigned long flags;
  90
  91                         local_irq_save(flags);
  92                         buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset;
  93                         xf(drive, NULL, buf + pc->b_count, count);
  94                         kunmap_atomic(buf - sg->offset, KM_IRQ0);
  95                         local_irq_restore(flags);
  96                 } else {
  97                         buf = sg_virt(sg);
  98                         xf(drive, NULL, buf + pc->b_count, count);
  99                 }
 100
 101                 bcount -= count;
 102                 pc->b_count += count;
 103                 done += count;
 104
 105                 if (pc->b_count == sg->length) {
 106                         if (!--pc->sg_cnt)
 107                                 break;
 108                         pc->sg = sg = sg_next(sg);
 109                         pc->b_count = 0;
 110                 }
 111         }
 112
 113         return done;
 114 }
 115 EXPORT_SYMBOL_GPL(ide_io_buffers);
 116
 117 void ide_init_pc(struct ide_atapi_pc *pc)
 118 {
 119         memset(pc, 0, sizeof(*pc));
 120         pc->buf = pc->pc_buf;
 121         pc->buf_size = IDE_PC_BUFFER_SIZE;
 122 }
 123 EXPORT_SYMBOL_GPL(ide_init_pc);
 124
 125 /*
 126  * Generate a new packet command request in front of the request queue, before
 127  * the current request, so that it will be processed immediately, on the next
 128  * pass through the driver.
 129  */
 130 static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk,
 131                               struct ide_atapi_pc *pc, struct request *rq)
 132 {
 133         blk_rq_init(NULL, rq);
 134         rq->cmd_type = REQ_TYPE_SPECIAL;
 135         rq->cmd_flags |= REQ_PREEMPT;
 136         rq->buffer = (char *)pc;
 137         rq->rq_disk = disk;
 138
 139         if (pc->req_xfer) {
 140                 rq->data = pc->buf;
 141                 rq->data_len = pc->req_xfer;
 142         }
 143
 144         memcpy(rq->cmd, pc->c, 12);
 145         if (drive->media == ide_tape)
 146                 rq->cmd[13] = REQ_IDETAPE_PC1;
 147
 148         drive->hwif->rq = NULL;
 149
 150         elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0);
 151 }
 152
 153 /*
 154  * Add a special packet command request to the tail of the request queue,
 155  * and wait for it to be serviced.
 156  */
 157 int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
 158                       struct ide_atapi_pc *pc)
 159 {
 160         struct request *rq;
 161         int error;
 162
 163         rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
 164         rq->cmd_type = REQ_TYPE_SPECIAL;
 165         rq->buffer = (char *)pc;
 166
 167         if (pc->req_xfer) {
 168                 rq->data = pc->buf;
 169                 rq->data_len = pc->req_xfer;
 170         }
 171
 172         memcpy(rq->cmd, pc->c, 12);
 173         if (drive->media == ide_tape)
 174                 rq->cmd[13] = REQ_IDETAPE_PC1;
 175         error = blk_execute_rq(drive->queue, disk, rq, 0);
 176         blk_put_request(rq);
 177
 178         return error;
 179 }
 180 EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
 181
 182 int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
 183 {
 184         struct ide_atapi_pc pc;
 185
 186         ide_init_pc(&pc);
 187         pc.c[0] = TEST_UNIT_READY;
 188
 189         return ide_queue_pc_tail(drive, disk, &pc);
 190 }
 191 EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
 192
 193 int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
 194 {
 195         struct ide_atapi_pc pc;
 196
 197         ide_init_pc(&pc);
 198         pc.c[0] = START_STOP;
 199         pc.c[4] = start;
 200
 201         if (drive->media == ide_tape)
 202                 pc.flags |= PC_FLAG_WAIT_FOR_DSC;
 203
 204         return ide_queue_pc_tail(drive, disk, &pc);
 205 }
 206 EXPORT_SYMBOL_GPL(ide_do_start_stop);
 207
 208 int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
 209 {
 210         struct ide_atapi_pc pc;
 211
 212         if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
 213                 return 0;
 214
 215         ide_init_pc(&pc);
 216         pc.c[0] = ALLOW_MEDIUM_REMOVAL;
 217         pc.c[4] = on;
 218
 219         return ide_queue_pc_tail(drive, disk, &pc);
 220 }
 221 EXPORT_SYMBOL_GPL(ide_set_media_lock);
 222
 223 void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
 224 {
 225         ide_init_pc(pc);
 226         pc->c[0] = REQUEST_SENSE;
 227         if (drive->media == ide_floppy) {
 228                 pc->c[4] = 255;
 229                 pc->req_xfer = 18;
 230         } else {
 231                 pc->c[4] = 20;
 232                 pc->req_xfer = 20;
 233         }
 234 }
 235 EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
 236
 237 /*
 238  * Called when an error was detected during the last packet command.
 239  * We queue a request sense packet command in the head of the request list.
 240  */
 241 void ide_retry_pc(ide_drive_t *drive, struct gendisk *disk)
 242 {
 243         struct request *rq = &drive->request_sense_rq;
 244         struct ide_atapi_pc *pc = &drive->request_sense_pc;
 245
 246         (void)ide_read_error(drive);
 247         ide_create_request_sense_cmd(drive, pc);
 248         if (drive->media == ide_tape)
 249                 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
 250         ide_queue_pc_head(drive, disk, pc, rq);
 251 }
 252 EXPORT_SYMBOL_GPL(ide_retry_pc);
 253
 254 int ide_cd_expiry(ide_drive_t *drive)
 255 {
 256         struct request *rq = drive->hwif->rq;
 257         unsigned long wait = 0;
 258
 259         debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]);
 260
 261         /*
 262          * Some commands are *slow* and normally take a long time to complete.
 263          * Usually we can use the ATAPI "disconnect" to bypass this, but not all
 264          * commands/drives support that. Let ide_timer_expiry keep polling us
 265          * for these.
 266          */
 267         switch (rq->cmd[0]) {
 268         case GPCMD_BLANK:
 269         case GPCMD_FORMAT_UNIT:
 270         case GPCMD_RESERVE_RZONE_TRACK:
 271         case GPCMD_CLOSE_TRACK:
 272         case GPCMD_FLUSH_CACHE:
 273                 wait = ATAPI_WAIT_PC;
 274                 break;
 275         default:
 276                 if (!(rq->cmd_flags & REQ_QUIET))
 277                         printk(KERN_INFO "cmd 0x%x timed out\n",
 278                                          rq->cmd[0]);
 279                 wait = 0;
 280                 break;
 281         }
 282         return wait;
 283 }
 284 EXPORT_SYMBOL_GPL(ide_cd_expiry);
 285
 286 int ide_cd_get_xferlen(struct request *rq)
 287 {
 288         if (blk_fs_request(rq))
 289                 return 32768;
 290         else if (blk_sense_request(rq) || blk_pc_request(rq) ||
 291                          rq->cmd_type == REQ_TYPE_ATA_PC)
 292                 return rq->data_len;
 293         else
 294                 return 0;
 295 }
 296 EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
 297
 298 void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
 299 {
 300         struct ide_cmd cmd;
 301
 302         memset(&cmd, 0, sizeof(cmd));
 303         cmd.tf_flags = IDE_TFLAG_IN_LBAH | IDE_TFLAG_IN_LBAM |
 304                        IDE_TFLAG_IN_NSECT;
 305
 306         drive->hwif->tp_ops->tf_read(drive, &cmd);
 307
 308         *bcount = (cmd.tf.lbah << 8) | cmd.tf.lbam;
 309         *ireason = cmd.tf.nsect & 3;
 310 }
 311 EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
 312
 313 /*
 314  * This is the usual interrupt handler which will be called during a packet
 315  * command.  We will transfer some of the data (as requested by the drive)
 316  * and will re-point interrupt handler to us.
 317  */
 318 static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
 319 {
 320         struct ide_atapi_pc *pc = drive->pc;
 321         ide_hwif_t *hwif = drive->hwif;
 322         struct ide_cmd *cmd = &hwif->cmd;
 323         struct request *rq = hwif->rq;
 324         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
 325         xfer_func_t *xferfunc;
 326         unsigned int timeout, done;
 327         u16 bcount;
 328         u8 stat, ireason, dsc = 0;
 329         u8 write = !!(pc->flags & PC_FLAG_WRITING);
 330
 331         debug_log("Enter %s - interrupt handler\n", __func__);
 332
 333         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 334                                                : WAIT_TAPE_CMD;
 335
 336         /* Clear the interrupt */
 337         stat = tp_ops->read_status(hwif);
 338
 339         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 340                 int rc;
 341
 342                 drive->waiting_for_dma = 0;
 343                 rc = hwif->dma_ops->dma_end(drive);
 344                 ide_dma_unmap_sg(drive, cmd);
 345
 346                 if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
 347                         if (drive->media == ide_floppy)
 348                                 printk(KERN_ERR "%s: DMA %s error\n",
 349                                         drive->name, rq_data_dir(pc->rq)
 350                                                      ? "write" : "read");
 351                         pc->flags |= PC_FLAG_DMA_ERROR;
 352                 } else {
 353                         pc->xferred = pc->req_xfer;
 354                         if (drive->pc_update_buffers)
 355                                 drive->pc_update_buffers(drive, pc);
 356                 }
 357                 debug_log("%s: DMA finished\n", drive->name);
 358         }
 359
 360         /* No more interrupts */
 361         if ((stat & ATA_DRQ) == 0) {
 362                 int uptodate;
 363
 364                 debug_log("Packet command completed, %d bytes transferred\n",
 365                           pc->xferred);
 366
 367                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 368
 369                 local_irq_enable_in_hardirq();
 370
 371                 if (drive->media == ide_tape &&
 372                     (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
 373                         stat &= ~ATA_ERR;
 374
 375                 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
 376                         /* Error detected */
 377                         debug_log("%s: I/O error\n", drive->name);
 378
 379                         if (drive->media != ide_tape)
 380                                 pc->rq->errors++;
 381
 382                         if (rq->cmd[0] == REQUEST_SENSE) {
 383                                 printk(KERN_ERR "%s: I/O error in request sense"
 384                                                 " command\n", drive->name);
 385                                 return ide_do_reset(drive);
 386                         }
 387
 388                         debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
 389
 390                         /* Retry operation */
 391                         ide_retry_pc(drive, rq->rq_disk);
 392
 393                         /* queued, but not started */
 394                         return ide_stopped;
 395                 }
 396                 pc->error = 0;
 397
 398                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
 399                         dsc = 1;
 400
 401                 /* Command finished - Call the callback function */
 402                 uptodate = drive->pc_callback(drive, dsc);
 403
 404                 if (uptodate == 0)
 405                         drive->failed_pc = NULL;
 406
 407                 if (blk_special_request(rq)) {
 408                         rq->errors = 0;
 409                         ide_complete_rq(drive, 0, blk_rq_bytes(rq));
 410                 } else {
 411                         if (blk_fs_request(rq) == 0 && uptodate <= 0) {
 412                                 if (rq->errors == 0)
 413                                         rq->errors = -EIO;
 414                         }
 415                         ide_complete_rq(drive, uptodate ? 0 : -EIO,
 416                                         ide_rq_bytes(rq));
 417                 }
 418
 419                 return ide_stopped;
 420         }
 421
 422         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 423                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 424                 printk(KERN_ERR "%s: The device wants to issue more interrupts "
 425                                 "in DMA mode\n", drive->name);
 426                 ide_dma_off(drive);
 427                 return ide_do_reset(drive);
 428         }
 429
 430         /* Get the number of bytes to transfer on this interrupt. */
 431         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
 432
 433         if (ireason & ATAPI_COD) {
 434                 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
 435                 return ide_do_reset(drive);
 436         }
 437
 438         if (((ireason & ATAPI_IO) == ATAPI_IO) == write) {
 439                 /* Hopefully, we will never get here */
 440                 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
 441                                 "to %s!\n", drive->name,
 442                                 (ireason & ATAPI_IO) ? "Write" : "Read",
 443                                 (ireason & ATAPI_IO) ? "Read" : "Write");
 444                 return ide_do_reset(drive);
 445         }
 446
 447         xferfunc = write ? tp_ops->output_data : tp_ops->input_data;
 448
 449         if ((drive->media == ide_floppy && !pc->buf) ||
 450             (drive->media == ide_tape && pc->bh)) {
 451                 done = drive->pc_io_buffers(drive, pc, bcount, write);
 452
 453                 /* FIXME: don't do partial completions */
 454                 if (drive->media == ide_floppy)
 455                         ide_complete_rq(drive, 0,
 456                                         done ? done : ide_rq_bytes(rq));
 457         } else {
 458                 done = min_t(unsigned int, bcount, pc->req_xfer - pc->xferred);
 459                 xferfunc(drive, NULL, pc->cur_pos, done);
 460         }
 461
 462         /* Update the current position */
 463         pc->xferred += done;
 464         pc->cur_pos += done;
 465
 466         bcount -= done;
 467
 468         if (bcount)
 469                 ide_pad_transfer(drive, write, bcount);
 470
 471         debug_log("[cmd %x] transferred %d bytes, padded %d bytes\n",
 472                   rq->cmd[0], done, bcount);
 473
 474         /* And set the interrupt handler again */
 475         ide_set_handler(drive, ide_pc_intr, timeout);
 476         return ide_started;
 477 }
 478
 479 static void ide_init_packet_cmd(struct ide_cmd *cmd, u32 tf_flags,
 480                                 u16 bcount, u8 dma)
 481 {
 482         cmd->protocol  = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
 483         cmd->tf_flags |= IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
 484                          IDE_TFLAG_OUT_FEATURE | tf_flags;
 485         cmd->tf.command = ATA_CMD_PACKET;
 486         cmd->tf.feature = dma;          /* Use PIO/DMA */
 487         cmd->tf.lbam    = bcount & 0xff;
 488         cmd->tf.lbah    = (bcount >> 8) & 0xff;
 489 }
 490
 491 static u8 ide_read_ireason(ide_drive_t *drive)
 492 {
 493         struct ide_cmd cmd;
 494
 495         memset(&cmd, 0, sizeof(cmd));
 496         cmd.tf_flags = IDE_TFLAG_IN_NSECT;
 497
 498         drive->hwif->tp_ops->tf_read(drive, &cmd);
 499
 500         return cmd.tf.nsect & 3;
 501 }
 502
 503 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
 504 {
 505         int retries = 100;
 506
 507         while (retries-- && ((ireason & ATAPI_COD) == 0 ||
 508                 (ireason & ATAPI_IO))) {
 509                 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 510                                 "a packet command, retrying\n", drive->name);
 511                 udelay(100);
 512                 ireason = ide_read_ireason(drive);
 513                 if (retries == 0) {
 514                         printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 515                                         "a packet command, ignoring\n",
 516                                         drive->name);
 517                         ireason |= ATAPI_COD;
 518                         ireason &= ~ATAPI_IO;
 519                 }
 520         }
 521
 522         return ireason;
 523 }
 524
 525 static int ide_delayed_transfer_pc(ide_drive_t *drive)
 526 {
 527         /* Send the actual packet */
 528         drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
 529
 530         /* Timeout for the packet command */
 531         return WAIT_FLOPPY_CMD;
 532 }
 533
 534 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
 535 {
 536         struct ide_atapi_pc *uninitialized_var(pc);
 537         ide_hwif_t *hwif = drive->hwif;
 538         struct request *rq = hwif->rq;
 539         ide_expiry_t *expiry;
 540         unsigned int timeout;
 541         int cmd_len;
 542         ide_startstop_t startstop;
 543         u8 ireason;
 544
 545         if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
 546                 printk(KERN_ERR "%s: Strange, packet command initiated yet "
 547                                 "DRQ isn't asserted\n", drive->name);
 548                 return startstop;
 549         }
 550
 551         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
 552                 if (drive->dma)
 553                         drive->waiting_for_dma = 1;
 554         }
 555
 556         if (dev_is_idecd(drive)) {
 557                 /* ATAPI commands get padded out to 12 bytes minimum */
 558                 cmd_len = COMMAND_SIZE(rq->cmd[0]);
 559                 if (cmd_len < ATAPI_MIN_CDB_BYTES)
 560                         cmd_len = ATAPI_MIN_CDB_BYTES;
 561
 562                 timeout = rq->timeout;
 563                 expiry  = ide_cd_expiry;
 564         } else {
 565                 pc = drive->pc;
 566
 567                 cmd_len = ATAPI_MIN_CDB_BYTES;
 568
 569                 /*
 570                  * If necessary schedule the packet transfer to occur 'timeout'
 571                  * miliseconds later in ide_delayed_transfer_pc() after the
 572                  * device says it's ready for a packet.
 573                  */
 574                 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
 575                         timeout = drive->pc_delay;
 576                         expiry = &ide_delayed_transfer_pc;
 577                 } else {
 578                         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 579                                                                : WAIT_TAPE_CMD;
 580                         expiry = NULL;
 581                 }
 582
 583                 ireason = ide_read_ireason(drive);
 584                 if (drive->media == ide_tape)
 585                         ireason = ide_wait_ireason(drive, ireason);
 586
 587                 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
 588                         printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
 589                                         "a packet command\n", drive->name);
 590
 591                         return ide_do_reset(drive);
 592                 }
 593         }
 594
 595         hwif->expiry = expiry;
 596
 597         /* Set the interrupt routine */
 598         ide_set_handler(drive,
 599                         (dev_is_idecd(drive) ? drive->irq_handler
 600                                              : ide_pc_intr),
 601                         timeout);
 602
 603         /* Send the actual packet */
 604         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
 605                 hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
 606
 607         /* Begin DMA, if necessary */
 608         if (dev_is_idecd(drive)) {
 609                 if (drive->dma)
 610                         hwif->dma_ops->dma_start(drive);
 611         } else {
 612                 if (pc->flags & PC_FLAG_DMA_OK) {
 613                         pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
 614                         hwif->dma_ops->dma_start(drive);
 615                 }
 616         }
 617
 618         return ide_started;
 619 }
 620
 621 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
 622 {
 623         struct ide_atapi_pc *pc;
 624         ide_hwif_t *hwif = drive->hwif;
 625         ide_expiry_t *expiry = NULL;
 626         struct request *rq = hwif->rq;
 627         unsigned int timeout;
 628         u32 tf_flags;
 629         u16 bcount;
 630         u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
 631
 632         if (dev_is_idecd(drive)) {
 633                 tf_flags = IDE_TFLAG_OUT_NSECT | IDE_TFLAG_OUT_LBAL;
 634                 bcount = ide_cd_get_xferlen(rq);
 635                 expiry = ide_cd_expiry;
 636                 timeout = ATAPI_WAIT_PC;
 637
 638                 if (drive->dma)
 639                         drive->dma = !ide_dma_prepare(drive, cmd);
 640         } else {
 641                 pc = drive->pc;
 642
 643                 /* We haven't transferred any data yet */
 644                 pc->xferred = 0;
 645                 pc->cur_pos = pc->buf;
 646
 647                 tf_flags = IDE_TFLAG_OUT_DEVICE;
 648                 bcount = ((drive->media == ide_tape) ?
 649                                 pc->req_xfer :
 650                                 min(pc->req_xfer, 63 * 1024));
 651
 652                 if (pc->flags & PC_FLAG_DMA_ERROR) {
 653                         pc->flags &= ~PC_FLAG_DMA_ERROR;
 654                         ide_dma_off(drive);
 655                 }
 656
 657                 if (pc->flags & PC_FLAG_DMA_OK)
 658                         drive->dma = !ide_dma_prepare(drive, cmd);
 659
 660                 if (!drive->dma)
 661                         pc->flags &= ~PC_FLAG_DMA_OK;
 662
 663                 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 664                                                        : WAIT_TAPE_CMD;
 665         }
 666
 667         ide_init_packet_cmd(cmd, tf_flags, bcount, drive->dma);
 668
 669         (void)do_rw_taskfile(drive, cmd);
 670
 671         if (drq_int) {
 672                 if (drive->dma)
 673                         drive->waiting_for_dma = 0;
 674                 hwif->expiry = expiry;
 675         }
 676
 677         ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
 678
 679         return drq_int ? ide_started : ide_transfer_pc(drive);
 680 }
 681 EXPORT_SYMBOL_GPL(ide_issue_pc);