Pileus Git - ~andy/linux/blob - 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         if (bcount) {
 114                 printk(KERN_ERR "%s: %d leftover bytes, %s\n", drive->name,
 115                         bcount, write ? "padding with zeros"
 116                                       : "discarding data");
 117                 ide_pad_transfer(drive, write, bcount);
 118         }
 119
 120         return done;
 121 }
 122 EXPORT_SYMBOL_GPL(ide_io_buffers);
 123
 124 void ide_init_pc(struct ide_atapi_pc *pc)
 125 {
 126         memset(pc, 0, sizeof(*pc));
 127         pc->buf = pc->pc_buf;
 128         pc->buf_size = IDE_PC_BUFFER_SIZE;
 129 }
 130 EXPORT_SYMBOL_GPL(ide_init_pc);
 131
 132 /*
 133  * Generate a new packet command request in front of the request queue, before
 134  * the current request, so that it will be processed immediately, on the next
 135  * pass through the driver.
 136  */
 137 static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk,
 138                               struct ide_atapi_pc *pc, struct request *rq)
 139 {
 140         blk_rq_init(NULL, rq);
 141         rq->cmd_type = REQ_TYPE_SPECIAL;
 142         rq->cmd_flags |= REQ_PREEMPT;
 143         rq->buffer = (char *)pc;
 144         rq->rq_disk = disk;
 145
 146         if (pc->req_xfer) {
 147                 rq->data = pc->buf;
 148                 rq->data_len = pc->req_xfer;
 149         }
 150
 151         memcpy(rq->cmd, pc->c, 12);
 152         if (drive->media == ide_tape)
 153                 rq->cmd[13] = REQ_IDETAPE_PC1;
 154
 155         drive->hwif->rq = NULL;
 156
 157         elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0);
 158 }
 159
 160 /*
 161  * Add a special packet command request to the tail of the request queue,
 162  * and wait for it to be serviced.
 163  */
 164 int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
 165                       struct ide_atapi_pc *pc)
 166 {
 167         struct request *rq;
 168         int error;
 169
 170         rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
 171         rq->cmd_type = REQ_TYPE_SPECIAL;
 172         rq->buffer = (char *)pc;
 173
 174         if (pc->req_xfer) {
 175                 rq->data = pc->buf;
 176                 rq->data_len = pc->req_xfer;
 177         }
 178
 179         memcpy(rq->cmd, pc->c, 12);
 180         if (drive->media == ide_tape)
 181                 rq->cmd[13] = REQ_IDETAPE_PC1;
 182         error = blk_execute_rq(drive->queue, disk, rq, 0);
 183         blk_put_request(rq);
 184
 185         return error;
 186 }
 187 EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
 188
 189 int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
 190 {
 191         struct ide_atapi_pc pc;
 192
 193         ide_init_pc(&pc);
 194         pc.c[0] = TEST_UNIT_READY;
 195
 196         return ide_queue_pc_tail(drive, disk, &pc);
 197 }
 198 EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
 199
 200 int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
 201 {
 202         struct ide_atapi_pc pc;
 203
 204         ide_init_pc(&pc);
 205         pc.c[0] = START_STOP;
 206         pc.c[4] = start;
 207
 208         if (drive->media == ide_tape)
 209                 pc.flags |= PC_FLAG_WAIT_FOR_DSC;
 210
 211         return ide_queue_pc_tail(drive, disk, &pc);
 212 }
 213 EXPORT_SYMBOL_GPL(ide_do_start_stop);
 214
 215 int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
 216 {
 217         struct ide_atapi_pc pc;
 218
 219         if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
 220                 return 0;
 221
 222         ide_init_pc(&pc);
 223         pc.c[0] = ALLOW_MEDIUM_REMOVAL;
 224         pc.c[4] = on;
 225
 226         return ide_queue_pc_tail(drive, disk, &pc);
 227 }
 228 EXPORT_SYMBOL_GPL(ide_set_media_lock);
 229
 230 void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
 231 {
 232         ide_init_pc(pc);
 233         pc->c[0] = REQUEST_SENSE;
 234         if (drive->media == ide_floppy) {
 235                 pc->c[4] = 255;
 236                 pc->req_xfer = 18;
 237         } else {
 238                 pc->c[4] = 20;
 239                 pc->req_xfer = 20;
 240         }
 241 }
 242 EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
 243
 244 /*
 245  * Called when an error was detected during the last packet command.
 246  * We queue a request sense packet command in the head of the request list.
 247  */
 248 void ide_retry_pc(ide_drive_t *drive, struct gendisk *disk)
 249 {
 250         struct request *rq = &drive->request_sense_rq;
 251         struct ide_atapi_pc *pc = &drive->request_sense_pc;
 252
 253         (void)ide_read_error(drive);
 254         ide_create_request_sense_cmd(drive, pc);
 255         if (drive->media == ide_tape)
 256                 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
 257         ide_queue_pc_head(drive, disk, pc, rq);
 258 }
 259 EXPORT_SYMBOL_GPL(ide_retry_pc);
 260
 261 int ide_cd_expiry(ide_drive_t *drive)
 262 {
 263         struct request *rq = drive->hwif->rq;
 264         unsigned long wait = 0;
 265
 266         debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]);
 267
 268         /*
 269          * Some commands are *slow* and normally take a long time to complete.
 270          * Usually we can use the ATAPI "disconnect" to bypass this, but not all
 271          * commands/drives support that. Let ide_timer_expiry keep polling us
 272          * for these.
 273          */
 274         switch (rq->cmd[0]) {
 275         case GPCMD_BLANK:
 276         case GPCMD_FORMAT_UNIT:
 277         case GPCMD_RESERVE_RZONE_TRACK:
 278         case GPCMD_CLOSE_TRACK:
 279         case GPCMD_FLUSH_CACHE:
 280                 wait = ATAPI_WAIT_PC;
 281                 break;
 282         default:
 283                 if (!(rq->cmd_flags & REQ_QUIET))
 284                         printk(KERN_INFO "cmd 0x%x timed out\n",
 285                                          rq->cmd[0]);
 286                 wait = 0;
 287                 break;
 288         }
 289         return wait;
 290 }
 291 EXPORT_SYMBOL_GPL(ide_cd_expiry);
 292
 293 int ide_cd_get_xferlen(struct request *rq)
 294 {
 295         if (blk_fs_request(rq))
 296                 return 32768;
 297         else if (blk_sense_request(rq) || blk_pc_request(rq) ||
 298                          rq->cmd_type == REQ_TYPE_ATA_PC)
 299                 return rq->data_len;
 300         else
 301                 return 0;
 302 }
 303 EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
 304
 305 void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
 306 {
 307         struct ide_cmd cmd;
 308
 309         memset(&cmd, 0, sizeof(cmd));
 310         cmd.tf_flags = IDE_TFLAG_IN_LBAH | IDE_TFLAG_IN_LBAM |
 311                        IDE_TFLAG_IN_NSECT;
 312
 313         drive->hwif->tp_ops->tf_read(drive, &cmd);
 314
 315         *bcount = (cmd.tf.lbah << 8) | cmd.tf.lbam;
 316         *ireason = cmd.tf.nsect & 3;
 317 }
 318 EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
 319
 320 /*
 321  * This is the usual interrupt handler which will be called during a packet
 322  * command.  We will transfer some of the data (as requested by the drive)
 323  * and will re-point interrupt handler to us.
 324  */
 325 static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
 326 {
 327         struct ide_atapi_pc *pc = drive->pc;
 328         ide_hwif_t *hwif = drive->hwif;
 329         struct ide_cmd *cmd = &hwif->cmd;
 330         struct request *rq = hwif->rq;
 331         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
 332         xfer_func_t *xferfunc;
 333         unsigned int timeout, temp;
 334         u16 bcount;
 335         u8 stat, ireason, dsc = 0;
 336
 337         debug_log("Enter %s - interrupt handler\n", __func__);
 338
 339         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 340                                                : WAIT_TAPE_CMD;
 341
 342         /* Clear the interrupt */
 343         stat = tp_ops->read_status(hwif);
 344
 345         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 346                 int rc;
 347
 348                 drive->waiting_for_dma = 0;
 349                 rc = hwif->dma_ops->dma_end(drive);
 350                 ide_dma_unmap_sg(drive, cmd);
 351
 352                 if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
 353                         if (drive->media == ide_floppy)
 354                                 printk(KERN_ERR "%s: DMA %s error\n",
 355                                         drive->name, rq_data_dir(pc->rq)
 356                                                      ? "write" : "read");
 357                         pc->flags |= PC_FLAG_DMA_ERROR;
 358                 } else {
 359                         pc->xferred = pc->req_xfer;
 360                         if (drive->pc_update_buffers)
 361                                 drive->pc_update_buffers(drive, pc);
 362                 }
 363                 debug_log("%s: DMA finished\n", drive->name);
 364         }
 365
 366         /* No more interrupts */
 367         if ((stat & ATA_DRQ) == 0) {
 368                 int uptodate;
 369
 370                 debug_log("Packet command completed, %d bytes transferred\n",
 371                           pc->xferred);
 372
 373                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 374
 375                 local_irq_enable_in_hardirq();
 376
 377                 if (drive->media == ide_tape &&
 378                     (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
 379                         stat &= ~ATA_ERR;
 380
 381                 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
 382                         /* Error detected */
 383                         debug_log("%s: I/O error\n", drive->name);
 384
 385                         if (drive->media != ide_tape)
 386                                 pc->rq->errors++;
 387
 388                         if (rq->cmd[0] == REQUEST_SENSE) {
 389                                 printk(KERN_ERR "%s: I/O error in request sense"
 390                                                 " command\n", drive->name);
 391                                 return ide_do_reset(drive);
 392                         }
 393
 394                         debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
 395
 396                         /* Retry operation */
 397                         ide_retry_pc(drive, rq->rq_disk);
 398
 399                         /* queued, but not started */
 400                         return ide_stopped;
 401                 }
 402                 pc->error = 0;
 403
 404                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
 405                         dsc = 1;
 406
 407                 /* Command finished - Call the callback function */
 408                 uptodate = drive->pc_callback(drive, dsc);
 409
 410                 if (uptodate == 0)
 411                         drive->failed_pc = NULL;
 412
 413                 if (blk_special_request(rq)) {
 414                         rq->errors = 0;
 415                         ide_complete_rq(drive, 0, blk_rq_bytes(rq));
 416                 } else {
 417                         if (blk_fs_request(rq) == 0 && uptodate <= 0) {
 418                                 if (rq->errors == 0)
 419                                         rq->errors = -EIO;
 420                         }
 421                         ide_complete_rq(drive, uptodate ? 0 : -EIO,
 422                                         ide_rq_bytes(rq));
 423                 }
 424
 425                 return ide_stopped;
 426         }
 427
 428         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 429                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 430                 printk(KERN_ERR "%s: The device wants to issue more interrupts "
 431                                 "in DMA mode\n", drive->name);
 432                 ide_dma_off(drive);
 433                 return ide_do_reset(drive);
 434         }
 435
 436         /* Get the number of bytes to transfer on this interrupt. */
 437         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
 438
 439         if (ireason & ATAPI_COD) {
 440                 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
 441                 return ide_do_reset(drive);
 442         }
 443
 444         if (((ireason & ATAPI_IO) == ATAPI_IO) ==
 445                 !!(pc->flags & PC_FLAG_WRITING)) {
 446                 /* Hopefully, we will never get here */
 447                 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
 448                                 "to %s!\n", drive->name,
 449                                 (ireason & ATAPI_IO) ? "Write" : "Read",
 450                                 (ireason & ATAPI_IO) ? "Read" : "Write");
 451                 return ide_do_reset(drive);
 452         }
 453
 454         if (!(pc->flags & PC_FLAG_WRITING)) {
 455                 /* Reading - Check that we have enough space */
 456                 temp = pc->xferred + bcount;
 457                 if (temp > pc->req_xfer) {
 458                         if (temp > pc->buf_size) {
 459                                 printk(KERN_ERR "%s: The device wants to send "
 460                                                 "us more data than expected - "
 461                                                 "discarding data\n",
 462                                                 drive->name);
 463
 464                                 ide_pad_transfer(drive, 0, bcount);
 465                                 goto next_irq;
 466                         }
 467                         debug_log("The device wants to send us more data than "
 468                                   "expected - allowing transfer\n");
 469                 }
 470                 xferfunc = tp_ops->input_data;
 471         } else
 472                 xferfunc = tp_ops->output_data;
 473
 474         if ((drive->media == ide_floppy && !pc->buf) ||
 475             (drive->media == ide_tape && pc->bh)) {
 476                 int done = drive->pc_io_buffers(drive, pc, bcount,
 477                                   !!(pc->flags & PC_FLAG_WRITING));
 478
 479                 /* FIXME: don't do partial completions */
 480                 if (drive->media == ide_floppy)
 481                         ide_complete_rq(drive, 0,
 482                                         done ? done : ide_rq_bytes(rq));
 483         } else
 484                 xferfunc(drive, NULL, pc->cur_pos, bcount);
 485
 486         /* Update the current position */
 487         pc->xferred += bcount;
 488         pc->cur_pos += bcount;
 489
 490         debug_log("[cmd %x] transferred %d bytes on that intr.\n",
 491                   rq->cmd[0], bcount);
 492 next_irq:
 493         /* And set the interrupt handler again */
 494         ide_set_handler(drive, ide_pc_intr, timeout);
 495         return ide_started;
 496 }
 497
 498 static void ide_init_packet_cmd(struct ide_cmd *cmd, u32 tf_flags,
 499                                 u16 bcount, u8 dma)
 500 {
 501         cmd->protocol  = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
 502         cmd->tf_flags |= IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
 503                          IDE_TFLAG_OUT_FEATURE | tf_flags;
 504         cmd->tf.command = ATA_CMD_PACKET;
 505         cmd->tf.feature = dma;          /* Use PIO/DMA */
 506         cmd->tf.lbam    = bcount & 0xff;
 507         cmd->tf.lbah    = (bcount >> 8) & 0xff;
 508 }
 509
 510 static u8 ide_read_ireason(ide_drive_t *drive)
 511 {
 512         struct ide_cmd cmd;
 513
 514         memset(&cmd, 0, sizeof(cmd));
 515         cmd.tf_flags = IDE_TFLAG_IN_NSECT;
 516
 517         drive->hwif->tp_ops->tf_read(drive, &cmd);
 518
 519         return cmd.tf.nsect & 3;
 520 }
 521
 522 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
 523 {
 524         int retries = 100;
 525
 526         while (retries-- && ((ireason & ATAPI_COD) == 0 ||
 527                 (ireason & ATAPI_IO))) {
 528                 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 529                                 "a packet command, retrying\n", drive->name);
 530                 udelay(100);
 531                 ireason = ide_read_ireason(drive);
 532                 if (retries == 0) {
 533                         printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 534                                         "a packet command, ignoring\n",
 535                                         drive->name);
 536                         ireason |= ATAPI_COD;
 537                         ireason &= ~ATAPI_IO;
 538                 }
 539         }
 540
 541         return ireason;
 542 }
 543
 544 static int ide_delayed_transfer_pc(ide_drive_t *drive)
 545 {
 546         /* Send the actual packet */
 547         drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
 548
 549         /* Timeout for the packet command */
 550         return WAIT_FLOPPY_CMD;
 551 }
 552
 553 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
 554 {
 555         struct ide_atapi_pc *uninitialized_var(pc);
 556         ide_hwif_t *hwif = drive->hwif;
 557         struct request *rq = hwif->rq;
 558         ide_expiry_t *expiry;
 559         unsigned int timeout;
 560         int cmd_len;
 561         ide_startstop_t startstop;
 562         u8 ireason;
 563
 564         if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
 565                 printk(KERN_ERR "%s: Strange, packet command initiated yet "
 566                                 "DRQ isn't asserted\n", drive->name);
 567                 return startstop;
 568         }
 569
 570         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
 571                 if (drive->dma)
 572                         drive->waiting_for_dma = 1;
 573         }
 574
 575         if (dev_is_idecd(drive)) {
 576                 /* ATAPI commands get padded out to 12 bytes minimum */
 577                 cmd_len = COMMAND_SIZE(rq->cmd[0]);
 578                 if (cmd_len < ATAPI_MIN_CDB_BYTES)
 579                         cmd_len = ATAPI_MIN_CDB_BYTES;
 580
 581                 timeout = rq->timeout;
 582                 expiry  = ide_cd_expiry;
 583         } else {
 584                 pc = drive->pc;
 585
 586                 cmd_len = ATAPI_MIN_CDB_BYTES;
 587
 588                 /*
 589                  * If necessary schedule the packet transfer to occur 'timeout'
 590                  * miliseconds later in ide_delayed_transfer_pc() after the
 591                  * device says it's ready for a packet.
 592                  */
 593                 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
 594                         timeout = drive->pc_delay;
 595                         expiry = &ide_delayed_transfer_pc;
 596                 } else {
 597                         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 598                                                                : WAIT_TAPE_CMD;
 599                         expiry = NULL;
 600                 }
 601
 602                 ireason = ide_read_ireason(drive);
 603                 if (drive->media == ide_tape)
 604                         ireason = ide_wait_ireason(drive, ireason);
 605
 606                 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
 607                         printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
 608                                         "a packet command\n", drive->name);
 609
 610                         return ide_do_reset(drive);
 611                 }
 612         }
 613
 614         hwif->expiry = expiry;
 615
 616         /* Set the interrupt routine */
 617         ide_set_handler(drive,
 618                         (dev_is_idecd(drive) ? drive->irq_handler
 619                                              : ide_pc_intr),
 620                         timeout);
 621
 622         /* Send the actual packet */
 623         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
 624                 hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
 625
 626         /* Begin DMA, if necessary */
 627         if (dev_is_idecd(drive)) {
 628                 if (drive->dma)
 629                         hwif->dma_ops->dma_start(drive);
 630         } else {
 631                 if (pc->flags & PC_FLAG_DMA_OK) {
 632                         pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
 633                         hwif->dma_ops->dma_start(drive);
 634                 }
 635         }
 636
 637         return ide_started;
 638 }
 639
 640 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
 641 {
 642         struct ide_atapi_pc *pc;
 643         ide_hwif_t *hwif = drive->hwif;
 644         ide_expiry_t *expiry = NULL;
 645         struct request *rq = hwif->rq;
 646         unsigned int timeout;
 647         u32 tf_flags;
 648         u16 bcount;
 649         u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
 650
 651         if (dev_is_idecd(drive)) {
 652                 tf_flags = IDE_TFLAG_OUT_NSECT | IDE_TFLAG_OUT_LBAL;
 653                 bcount = ide_cd_get_xferlen(rq);
 654                 expiry = ide_cd_expiry;
 655                 timeout = ATAPI_WAIT_PC;
 656
 657                 if (drive->dma)
 658                         drive->dma = !ide_dma_prepare(drive, cmd);
 659         } else {
 660                 pc = drive->pc;
 661
 662                 /* We haven't transferred any data yet */
 663                 pc->xferred = 0;
 664                 pc->cur_pos = pc->buf;
 665
 666                 tf_flags = IDE_TFLAG_OUT_DEVICE;
 667                 bcount = ((drive->media == ide_tape) ?
 668                                 pc->req_xfer :
 669                                 min(pc->req_xfer, 63 * 1024));
 670
 671                 if (pc->flags & PC_FLAG_DMA_ERROR) {
 672                         pc->flags &= ~PC_FLAG_DMA_ERROR;
 673                         ide_dma_off(drive);
 674                 }
 675
 676                 if (pc->flags & PC_FLAG_DMA_OK)
 677                         drive->dma = !ide_dma_prepare(drive, cmd);
 678
 679                 if (!drive->dma)
 680                         pc->flags &= ~PC_FLAG_DMA_OK;
 681
 682                 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
 683                                                        : WAIT_TAPE_CMD;
 684         }
 685
 686         ide_init_packet_cmd(cmd, tf_flags, bcount, drive->dma);
 687
 688         (void)do_rw_taskfile(drive, cmd);
 689
 690         if (drq_int) {
 691                 if (drive->dma)
 692                         drive->waiting_for_dma = 0;
 693                 hwif->expiry = expiry;
 694         }
 695
 696         ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
 697
 698         return drq_int ? ide_started : ide_transfer_pc(drive);
 699 }
 700 EXPORT_SYMBOL_GPL(ide_issue_pc);