ide-atapi.c revision 22aa4b32a19b1f231d4ce7e9af6354b577a22a35
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 <scsi/scsi.h> 10 11#ifdef DEBUG 12#define debug_log(fmt, args...) \ 13 printk(KERN_INFO "ide: " fmt, ## args) 14#else 15#define debug_log(fmt, args...) do {} while (0) 16#endif 17 18#define ATAPI_MIN_CDB_BYTES 12 19 20static inline int dev_is_idecd(ide_drive_t *drive) 21{ 22 return drive->media == ide_cdrom || drive->media == ide_optical; 23} 24 25/* 26 * Check whether we can support a device, 27 * based on the ATAPI IDENTIFY command results. 28 */ 29int ide_check_atapi_device(ide_drive_t *drive, const char *s) 30{ 31 u16 *id = drive->id; 32 u8 gcw[2], protocol, device_type, removable, drq_type, packet_size; 33 34 *((u16 *)&gcw) = id[ATA_ID_CONFIG]; 35 36 protocol = (gcw[1] & 0xC0) >> 6; 37 device_type = gcw[1] & 0x1F; 38 removable = (gcw[0] & 0x80) >> 7; 39 drq_type = (gcw[0] & 0x60) >> 5; 40 packet_size = gcw[0] & 0x03; 41 42#ifdef CONFIG_PPC 43 /* kludge for Apple PowerBook internal zip */ 44 if (drive->media == ide_floppy && device_type == 5 && 45 !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") && 46 strstr((char *)&id[ATA_ID_PROD], "ZIP")) 47 device_type = 0; 48#endif 49 50 if (protocol != 2) 51 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n", 52 s, drive->name, protocol); 53 else if ((drive->media == ide_floppy && device_type != 0) || 54 (drive->media == ide_tape && device_type != 1)) 55 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n", 56 s, drive->name, device_type); 57 else if (removable == 0) 58 printk(KERN_ERR "%s: %s: the removable flag is not set\n", 59 s, drive->name); 60 else if (drive->media == ide_floppy && drq_type == 3) 61 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not " 62 "supported\n", s, drive->name, drq_type); 63 else if (packet_size != 0) 64 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 " 65 "bytes\n", s, drive->name, packet_size); 66 else 67 return 1; 68 return 0; 69} 70EXPORT_SYMBOL_GPL(ide_check_atapi_device); 71 72/* PIO data transfer routine using the scatter gather table. */ 73int ide_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 74 unsigned int bcount, int write) 75{ 76 ide_hwif_t *hwif = drive->hwif; 77 const struct ide_tp_ops *tp_ops = hwif->tp_ops; 78 xfer_func_t *xf = write ? tp_ops->output_data : tp_ops->input_data; 79 struct scatterlist *sg = pc->sg; 80 char *buf; 81 int count, done = 0; 82 83 while (bcount) { 84 count = min(sg->length - pc->b_count, bcount); 85 86 if (PageHighMem(sg_page(sg))) { 87 unsigned long flags; 88 89 local_irq_save(flags); 90 buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset; 91 xf(drive, NULL, buf + pc->b_count, count); 92 kunmap_atomic(buf - sg->offset, KM_IRQ0); 93 local_irq_restore(flags); 94 } else { 95 buf = sg_virt(sg); 96 xf(drive, NULL, buf + pc->b_count, count); 97 } 98 99 bcount -= count; 100 pc->b_count += count; 101 done += count; 102 103 if (pc->b_count == sg->length) { 104 if (!--pc->sg_cnt) 105 break; 106 pc->sg = sg = sg_next(sg); 107 pc->b_count = 0; 108 } 109 } 110 111 if (bcount) { 112 printk(KERN_ERR "%s: %d leftover bytes, %s\n", drive->name, 113 bcount, write ? "padding with zeros" 114 : "discarding data"); 115 ide_pad_transfer(drive, write, bcount); 116 } 117 118 return done; 119} 120EXPORT_SYMBOL_GPL(ide_io_buffers); 121 122void ide_init_pc(struct ide_atapi_pc *pc) 123{ 124 memset(pc, 0, sizeof(*pc)); 125 pc->buf = pc->pc_buf; 126 pc->buf_size = IDE_PC_BUFFER_SIZE; 127} 128EXPORT_SYMBOL_GPL(ide_init_pc); 129 130/* 131 * Generate a new packet command request in front of the request queue, before 132 * the current request, so that it will be processed immediately, on the next 133 * pass through the driver. 134 */ 135static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk, 136 struct ide_atapi_pc *pc, struct request *rq) 137{ 138 blk_rq_init(NULL, rq); 139 rq->cmd_type = REQ_TYPE_SPECIAL; 140 rq->cmd_flags |= REQ_PREEMPT; 141 rq->buffer = (char *)pc; 142 rq->rq_disk = disk; 143 144 if (pc->req_xfer) { 145 rq->data = pc->buf; 146 rq->data_len = pc->req_xfer; 147 } 148 149 memcpy(rq->cmd, pc->c, 12); 150 if (drive->media == ide_tape) 151 rq->cmd[13] = REQ_IDETAPE_PC1; 152 153 drive->hwif->rq = NULL; 154 155 elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0); 156} 157 158/* 159 * Add a special packet command request to the tail of the request queue, 160 * and wait for it to be serviced. 161 */ 162int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk, 163 struct ide_atapi_pc *pc) 164{ 165 struct request *rq; 166 int error; 167 168 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 169 rq->cmd_type = REQ_TYPE_SPECIAL; 170 rq->buffer = (char *)pc; 171 172 if (pc->req_xfer) { 173 rq->data = pc->buf; 174 rq->data_len = pc->req_xfer; 175 } 176 177 memcpy(rq->cmd, pc->c, 12); 178 if (drive->media == ide_tape) 179 rq->cmd[13] = REQ_IDETAPE_PC1; 180 error = blk_execute_rq(drive->queue, disk, rq, 0); 181 blk_put_request(rq); 182 183 return error; 184} 185EXPORT_SYMBOL_GPL(ide_queue_pc_tail); 186 187int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk) 188{ 189 struct ide_atapi_pc pc; 190 191 ide_init_pc(&pc); 192 pc.c[0] = TEST_UNIT_READY; 193 194 return ide_queue_pc_tail(drive, disk, &pc); 195} 196EXPORT_SYMBOL_GPL(ide_do_test_unit_ready); 197 198int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start) 199{ 200 struct ide_atapi_pc pc; 201 202 ide_init_pc(&pc); 203 pc.c[0] = START_STOP; 204 pc.c[4] = start; 205 206 if (drive->media == ide_tape) 207 pc.flags |= PC_FLAG_WAIT_FOR_DSC; 208 209 return ide_queue_pc_tail(drive, disk, &pc); 210} 211EXPORT_SYMBOL_GPL(ide_do_start_stop); 212 213int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on) 214{ 215 struct ide_atapi_pc pc; 216 217 if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0) 218 return 0; 219 220 ide_init_pc(&pc); 221 pc.c[0] = ALLOW_MEDIUM_REMOVAL; 222 pc.c[4] = on; 223 224 return ide_queue_pc_tail(drive, disk, &pc); 225} 226EXPORT_SYMBOL_GPL(ide_set_media_lock); 227 228void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc) 229{ 230 ide_init_pc(pc); 231 pc->c[0] = REQUEST_SENSE; 232 if (drive->media == ide_floppy) { 233 pc->c[4] = 255; 234 pc->req_xfer = 18; 235 } else { 236 pc->c[4] = 20; 237 pc->req_xfer = 20; 238 } 239} 240EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd); 241 242/* 243 * Called when an error was detected during the last packet command. 244 * We queue a request sense packet command in the head of the request list. 245 */ 246void ide_retry_pc(ide_drive_t *drive, struct gendisk *disk) 247{ 248 struct request *rq = &drive->request_sense_rq; 249 struct ide_atapi_pc *pc = &drive->request_sense_pc; 250 251 (void)ide_read_error(drive); 252 ide_create_request_sense_cmd(drive, pc); 253 if (drive->media == ide_tape) 254 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 255 ide_queue_pc_head(drive, disk, pc, rq); 256} 257EXPORT_SYMBOL_GPL(ide_retry_pc); 258 259int ide_cd_expiry(ide_drive_t *drive) 260{ 261 struct request *rq = drive->hwif->rq; 262 unsigned long wait = 0; 263 264 debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]); 265 266 /* 267 * Some commands are *slow* and normally take a long time to complete. 268 * Usually we can use the ATAPI "disconnect" to bypass this, but not all 269 * commands/drives support that. Let ide_timer_expiry keep polling us 270 * for these. 271 */ 272 switch (rq->cmd[0]) { 273 case GPCMD_BLANK: 274 case GPCMD_FORMAT_UNIT: 275 case GPCMD_RESERVE_RZONE_TRACK: 276 case GPCMD_CLOSE_TRACK: 277 case GPCMD_FLUSH_CACHE: 278 wait = ATAPI_WAIT_PC; 279 break; 280 default: 281 if (!(rq->cmd_flags & REQ_QUIET)) 282 printk(KERN_INFO "cmd 0x%x timed out\n", 283 rq->cmd[0]); 284 wait = 0; 285 break; 286 } 287 return wait; 288} 289EXPORT_SYMBOL_GPL(ide_cd_expiry); 290 291int ide_cd_get_xferlen(struct request *rq) 292{ 293 if (blk_fs_request(rq)) 294 return 32768; 295 else if (blk_sense_request(rq) || blk_pc_request(rq) || 296 rq->cmd_type == REQ_TYPE_ATA_PC) 297 return rq->data_len; 298 else 299 return 0; 300} 301EXPORT_SYMBOL_GPL(ide_cd_get_xferlen); 302 303void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason) 304{ 305 struct ide_cmd cmd; 306 307 memset(&cmd, 0, sizeof(cmd)); 308 cmd.tf_flags = IDE_TFLAG_IN_LBAH | IDE_TFLAG_IN_LBAM | 309 IDE_TFLAG_IN_NSECT; 310 311 drive->hwif->tp_ops->tf_read(drive, &cmd); 312 313 *bcount = (cmd.tf.lbah << 8) | cmd.tf.lbam; 314 *ireason = cmd.tf.nsect & 3; 315} 316EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason); 317 318/* 319 * This is the usual interrupt handler which will be called during a packet 320 * command. We will transfer some of the data (as requested by the drive) 321 * and will re-point interrupt handler to us. 322 */ 323static ide_startstop_t ide_pc_intr(ide_drive_t *drive) 324{ 325 struct ide_atapi_pc *pc = drive->pc; 326 ide_hwif_t *hwif = drive->hwif; 327 struct request *rq = hwif->rq; 328 const struct ide_tp_ops *tp_ops = hwif->tp_ops; 329 xfer_func_t *xferfunc; 330 unsigned int timeout, temp; 331 u16 bcount; 332 u8 stat, ireason, dsc = 0; 333 334 debug_log("Enter %s - interrupt handler\n", __func__); 335 336 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD 337 : WAIT_TAPE_CMD; 338 339 /* Clear the interrupt */ 340 stat = tp_ops->read_status(hwif); 341 342 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 343 if (hwif->dma_ops->dma_end(drive) || 344 (drive->media == ide_tape && (stat & ATA_ERR))) { 345 if (drive->media == ide_floppy) 346 printk(KERN_ERR "%s: DMA %s error\n", 347 drive->name, rq_data_dir(pc->rq) 348 ? "write" : "read"); 349 pc->flags |= PC_FLAG_DMA_ERROR; 350 } else { 351 pc->xferred = pc->req_xfer; 352 if (drive->pc_update_buffers) 353 drive->pc_update_buffers(drive, pc); 354 } 355 debug_log("%s: DMA finished\n", drive->name); 356 } 357 358 /* No more interrupts */ 359 if ((stat & ATA_DRQ) == 0) { 360 int uptodate; 361 362 debug_log("Packet command completed, %d bytes transferred\n", 363 pc->xferred); 364 365 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 366 367 local_irq_enable_in_hardirq(); 368 369 if (drive->media == ide_tape && 370 (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE) 371 stat &= ~ATA_ERR; 372 373 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) { 374 /* Error detected */ 375 debug_log("%s: I/O error\n", drive->name); 376 377 if (drive->media != ide_tape) 378 pc->rq->errors++; 379 380 if (rq->cmd[0] == REQUEST_SENSE) { 381 printk(KERN_ERR "%s: I/O error in request sense" 382 " command\n", drive->name); 383 return ide_do_reset(drive); 384 } 385 386 debug_log("[cmd %x]: check condition\n", rq->cmd[0]); 387 388 /* Retry operation */ 389 ide_retry_pc(drive, rq->rq_disk); 390 391 /* queued, but not started */ 392 return ide_stopped; 393 } 394 pc->error = 0; 395 396 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0) 397 dsc = 1; 398 399 /* Command finished - Call the callback function */ 400 uptodate = drive->pc_callback(drive, dsc); 401 402 if (uptodate == 0) 403 drive->failed_pc = NULL; 404 405 if (blk_special_request(rq)) 406 ide_complete_rq(drive, 0); 407 else 408 ide_end_request(drive, uptodate, 0); 409 410 return ide_stopped; 411 } 412 413 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 414 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 415 printk(KERN_ERR "%s: The device wants to issue more interrupts " 416 "in DMA mode\n", drive->name); 417 ide_dma_off(drive); 418 return ide_do_reset(drive); 419 } 420 421 /* Get the number of bytes to transfer on this interrupt. */ 422 ide_read_bcount_and_ireason(drive, &bcount, &ireason); 423 424 if (ireason & ATAPI_COD) { 425 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__); 426 return ide_do_reset(drive); 427 } 428 429 if (((ireason & ATAPI_IO) == ATAPI_IO) == 430 !!(pc->flags & PC_FLAG_WRITING)) { 431 /* Hopefully, we will never get here */ 432 printk(KERN_ERR "%s: We wanted to %s, but the device wants us " 433 "to %s!\n", drive->name, 434 (ireason & ATAPI_IO) ? "Write" : "Read", 435 (ireason & ATAPI_IO) ? "Read" : "Write"); 436 return ide_do_reset(drive); 437 } 438 439 if (!(pc->flags & PC_FLAG_WRITING)) { 440 /* Reading - Check that we have enough space */ 441 temp = pc->xferred + bcount; 442 if (temp > pc->req_xfer) { 443 if (temp > pc->buf_size) { 444 printk(KERN_ERR "%s: The device wants to send " 445 "us more data than expected - " 446 "discarding data\n", 447 drive->name); 448 449 ide_pad_transfer(drive, 0, bcount); 450 goto next_irq; 451 } 452 debug_log("The device wants to send us more data than " 453 "expected - allowing transfer\n"); 454 } 455 xferfunc = tp_ops->input_data; 456 } else 457 xferfunc = tp_ops->output_data; 458 459 if ((drive->media == ide_floppy && !pc->buf) || 460 (drive->media == ide_tape && pc->bh)) { 461 int done = drive->pc_io_buffers(drive, pc, bcount, 462 !!(pc->flags & PC_FLAG_WRITING)); 463 464 /* FIXME: don't do partial completions */ 465 if (drive->media == ide_floppy) 466 ide_end_request(drive, 1, done >> 9); 467 } else 468 xferfunc(drive, NULL, pc->cur_pos, bcount); 469 470 /* Update the current position */ 471 pc->xferred += bcount; 472 pc->cur_pos += bcount; 473 474 debug_log("[cmd %x] transferred %d bytes on that intr.\n", 475 rq->cmd[0], bcount); 476next_irq: 477 /* And set the interrupt handler again */ 478 ide_set_handler(drive, ide_pc_intr, timeout, NULL); 479 return ide_started; 480} 481 482static void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount) 483{ 484 ide_hwif_t *hwif = drive->hwif; 485 struct ide_cmd cmd; 486 u8 dma = drive->dma; 487 488 memset(&cmd, 0, sizeof(cmd)); 489 cmd.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 490 IDE_TFLAG_OUT_FEATURE | tf_flags; 491 cmd.tf.feature = dma; /* Use PIO/DMA */ 492 cmd.tf.lbam = bcount & 0xff; 493 cmd.tf.lbah = (bcount >> 8) & 0xff; 494 495 ide_tf_dump(drive->name, &cmd.tf); 496 hwif->tp_ops->set_irq(hwif, 1); 497 SELECT_MASK(drive, 0); 498 hwif->tp_ops->tf_load(drive, &cmd); 499} 500 501static u8 ide_read_ireason(ide_drive_t *drive) 502{ 503 struct ide_cmd cmd; 504 505 memset(&cmd, 0, sizeof(cmd)); 506 cmd.tf_flags = IDE_TFLAG_IN_NSECT; 507 508 drive->hwif->tp_ops->tf_read(drive, &cmd); 509 510 return cmd.tf.nsect & 3; 511} 512 513static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason) 514{ 515 int retries = 100; 516 517 while (retries-- && ((ireason & ATAPI_COD) == 0 || 518 (ireason & ATAPI_IO))) { 519 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 520 "a packet command, retrying\n", drive->name); 521 udelay(100); 522 ireason = ide_read_ireason(drive); 523 if (retries == 0) { 524 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 525 "a packet command, ignoring\n", 526 drive->name); 527 ireason |= ATAPI_COD; 528 ireason &= ~ATAPI_IO; 529 } 530 } 531 532 return ireason; 533} 534 535static int ide_delayed_transfer_pc(ide_drive_t *drive) 536{ 537 /* Send the actual packet */ 538 drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12); 539 540 /* Timeout for the packet command */ 541 return WAIT_FLOPPY_CMD; 542} 543 544static ide_startstop_t ide_transfer_pc(ide_drive_t *drive) 545{ 546 struct ide_atapi_pc *uninitialized_var(pc); 547 ide_hwif_t *hwif = drive->hwif; 548 struct request *rq = hwif->rq; 549 ide_expiry_t *expiry; 550 unsigned int timeout; 551 int cmd_len; 552 ide_startstop_t startstop; 553 u8 ireason; 554 555 if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) { 556 printk(KERN_ERR "%s: Strange, packet command initiated yet " 557 "DRQ isn't asserted\n", drive->name); 558 return startstop; 559 } 560 561 if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) { 562 if (drive->dma) 563 drive->waiting_for_dma = 1; 564 } 565 566 if (dev_is_idecd(drive)) { 567 /* ATAPI commands get padded out to 12 bytes minimum */ 568 cmd_len = COMMAND_SIZE(rq->cmd[0]); 569 if (cmd_len < ATAPI_MIN_CDB_BYTES) 570 cmd_len = ATAPI_MIN_CDB_BYTES; 571 572 timeout = rq->timeout; 573 expiry = ide_cd_expiry; 574 } else { 575 pc = drive->pc; 576 577 cmd_len = ATAPI_MIN_CDB_BYTES; 578 579 /* 580 * If necessary schedule the packet transfer to occur 'timeout' 581 * miliseconds later in ide_delayed_transfer_pc() after the 582 * device says it's ready for a packet. 583 */ 584 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) { 585 timeout = drive->pc_delay; 586 expiry = &ide_delayed_transfer_pc; 587 } else { 588 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD 589 : WAIT_TAPE_CMD; 590 expiry = NULL; 591 } 592 593 ireason = ide_read_ireason(drive); 594 if (drive->media == ide_tape) 595 ireason = ide_wait_ireason(drive, ireason); 596 597 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) { 598 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing " 599 "a packet command\n", drive->name); 600 601 return ide_do_reset(drive); 602 } 603 } 604 605 /* Set the interrupt routine */ 606 ide_set_handler(drive, 607 (dev_is_idecd(drive) ? drive->irq_handler 608 : ide_pc_intr), 609 timeout, expiry); 610 611 /* Begin DMA, if necessary */ 612 if (dev_is_idecd(drive)) { 613 if (drive->dma) 614 hwif->dma_ops->dma_start(drive); 615 } else { 616 if (pc->flags & PC_FLAG_DMA_OK) { 617 pc->flags |= PC_FLAG_DMA_IN_PROGRESS; 618 hwif->dma_ops->dma_start(drive); 619 } 620 } 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 return ide_started; 627} 628 629ide_startstop_t ide_issue_pc(ide_drive_t *drive) 630{ 631 struct ide_atapi_pc *pc; 632 ide_hwif_t *hwif = drive->hwif; 633 ide_expiry_t *expiry = NULL; 634 struct request *rq = hwif->rq; 635 unsigned int timeout; 636 u32 tf_flags; 637 u16 bcount; 638 639 if (dev_is_idecd(drive)) { 640 tf_flags = IDE_TFLAG_OUT_NSECT | IDE_TFLAG_OUT_LBAL; 641 bcount = ide_cd_get_xferlen(rq); 642 expiry = ide_cd_expiry; 643 timeout = ATAPI_WAIT_PC; 644 645 if (drive->dma) { 646 if (ide_build_sglist(drive, rq)) 647 drive->dma = !hwif->dma_ops->dma_setup(drive); 648 else 649 drive->dma = 0; 650 } 651 } else { 652 pc = drive->pc; 653 654 /* We haven't transferred any data yet */ 655 pc->xferred = 0; 656 pc->cur_pos = pc->buf; 657 658 tf_flags = IDE_TFLAG_OUT_DEVICE; 659 bcount = ((drive->media == ide_tape) ? 660 pc->req_xfer : 661 min(pc->req_xfer, 63 * 1024)); 662 663 if (pc->flags & PC_FLAG_DMA_ERROR) { 664 pc->flags &= ~PC_FLAG_DMA_ERROR; 665 ide_dma_off(drive); 666 } 667 668 if ((pc->flags & PC_FLAG_DMA_OK) && 669 (drive->dev_flags & IDE_DFLAG_USING_DMA)) { 670 if (ide_build_sglist(drive, rq)) 671 drive->dma = !hwif->dma_ops->dma_setup(drive); 672 else 673 drive->dma = 0; 674 } 675 676 if (!drive->dma) 677 pc->flags &= ~PC_FLAG_DMA_OK; 678 679 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD 680 : WAIT_TAPE_CMD; 681 } 682 683 ide_pktcmd_tf_load(drive, tf_flags, bcount); 684 685 /* Issue the packet command */ 686 if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) { 687 if (drive->dma) 688 drive->waiting_for_dma = 0; 689 ide_execute_command(drive, ATA_CMD_PACKET, ide_transfer_pc, 690 timeout, expiry); 691 return ide_started; 692 } else { 693 ide_execute_pkt_cmd(drive); 694 return ide_transfer_pc(drive); 695 } 696} 697EXPORT_SYMBOL_GPL(ide_issue_pc); 698