drivers/ide/ide-lib.c

   1 #include <linux/module.h>
   2 #include <linux/types.h>
   3 #include <linux/string.h>
   4 #include <linux/kernel.h>
   5 #include <linux/timer.h>
   6 #include <linux/mm.h>
   7 #include <linux/interrupt.h>
   8 #include <linux/major.h>
   9 #include <linux/errno.h>
  10 #include <linux/genhd.h>
  11 #include <linux/blkpg.h>
  12 #include <linux/slab.h>
  13 #include <linux/pci.h>
  14 #include <linux/delay.h>
  15 #include <linux/hdreg.h>
  16 #include <linux/ide.h>
  17 #include <linux/bitops.h>
  18
  19 #include <asm/byteorder.h>
  20 #include <asm/irq.h>
  21 #include <asm/uaccess.h>
  22 #include <asm/io.h>
  23
  24 /*
  25  *      IDE library routines. These are plug in code that most
  26  *      drivers can use but occasionally may be weird enough
  27  *      to want to do their own thing with
  28  *
  29  *      Add common non I/O op stuff here. Make sure it has proper
  30  *      kernel-doc function headers or your patch will be rejected
  31  */
  32
  33 static const char *udma_str[] =
  34          { "UDMA/16", "UDMA/25",  "UDMA/33",  "UDMA/44",
  35            "UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
  36 static const char *mwdma_str[] =
  37         { "MWDMA0", "MWDMA1", "MWDMA2" };
  38 static const char *swdma_str[] =
  39         { "SWDMA0", "SWDMA1", "SWDMA2" };
  40 static const char *pio_str[] =
  41         { "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5" };
  42
  43 /**
  44  *      ide_xfer_verbose        -       return IDE mode names
  45  *      @mode: transfer mode
  46  *
  47  *      Returns a constant string giving the name of the mode
  48  *      requested.
  49  */
  50
  51 const char *ide_xfer_verbose(u8 mode)
  52 {
  53         const char *s;
  54         u8 i = mode & 0xf;
  55
  56         if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
  57                 s = udma_str[i];
  58         else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_2)
  59                 s = mwdma_str[i];
  60         else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
  61                 s = swdma_str[i];
  62         else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_5)
  63                 s = pio_str[i & 0x7];
  64         else if (mode == XFER_PIO_SLOW)
  65                 s = "PIO SLOW";
  66         else
  67                 s = "XFER ERROR";
  68
  69         return s;
  70 }
  71
  72 EXPORT_SYMBOL(ide_xfer_verbose);
  73
  74 /**
  75  *      ide_rate_filter         -       filter transfer mode
  76  *      @drive: IDE device
  77  *      @speed: desired speed
  78  *
  79  *      Given the available transfer modes this function returns
  80  *      the best available speed at or below the speed requested.
  81  *
  82  *      TODO: check device PIO capabilities
  83  */
  84
  85 static u8 ide_rate_filter(ide_drive_t *drive, u8 speed)
  86 {
  87         ide_hwif_t *hwif = drive->hwif;
  88         u8 mode = ide_find_dma_mode(drive, speed);
  89
  90         if (mode == 0) {
  91                 if (hwif->pio_mask)
  92                         mode = fls(hwif->pio_mask) - 1 + XFER_PIO_0;
  93                 else
  94                         mode = XFER_PIO_4;
  95         }
  96
  97 //      printk("%s: mode 0x%02x, speed 0x%02x\n", __FUNCTION__, mode, speed);
  98
  99         return min(speed, mode);
 100 }
 101
 102 /*
 103  * Standard (generic) timings for PIO modes, from ATA2 specification.
 104  * These timings are for access to the IDE data port register *only*.
 105  * Some drives may specify a mode, while also specifying a different
 106  * value for cycle_time (from drive identification data).
 107  */
 108 const ide_pio_timings_t ide_pio_timings[6] = {
 109         { 70,   165,    600 },  /* PIO Mode 0 */
 110         { 50,   125,    383 },  /* PIO Mode 1 */
 111         { 30,   100,    240 },  /* PIO Mode 2 */
 112         { 30,   80,     180 },  /* PIO Mode 3 with IORDY */
 113         { 25,   70,     120 },  /* PIO Mode 4 with IORDY */
 114         { 20,   50,     100 }   /* PIO Mode 5 with IORDY (nonstandard) */
 115 };
 116
 117 EXPORT_SYMBOL_GPL(ide_pio_timings);
 118
 119 /*
 120  * Shared data/functions for determining best PIO mode for an IDE drive.
 121  * Most of this stuff originally lived in cmd640.c, and changes to the
 122  * ide_pio_blacklist[] table should be made with EXTREME CAUTION to avoid
 123  * breaking the fragile cmd640.c support.
 124  */
 125
 126 /*
 127  * Black list. Some drives incorrectly report their maximal PIO mode,
 128  * at least in respect to CMD640. Here we keep info on some known drives.
 129  */
 130 static struct ide_pio_info {
 131         const char      *name;
 132         int             pio;
 133 } ide_pio_blacklist [] = {
 134 /*      { "Conner Peripherals 1275MB - CFS1275A", 4 }, */
 135         { "Conner Peripherals 540MB - CFS540A", 3 },
 136
 137         { "WDC AC2700",  3 },
 138         { "WDC AC2540",  3 },
 139         { "WDC AC2420",  3 },
 140         { "WDC AC2340",  3 },
 141         { "WDC AC2250",  0 },
 142         { "WDC AC2200",  0 },
 143         { "WDC AC21200", 4 },
 144         { "WDC AC2120",  0 },
 145         { "WDC AC2850",  3 },
 146         { "WDC AC1270",  3 },
 147         { "WDC AC1170",  1 },
 148         { "WDC AC1210",  1 },
 149         { "WDC AC280",   0 },
 150 /*      { "WDC AC21000", 4 }, */
 151         { "WDC AC31000", 3 },
 152         { "WDC AC31200", 3 },
 153 /*      { "WDC AC31600", 4 }, */
 154
 155         { "Maxtor 7131 AT", 1 },
 156         { "Maxtor 7171 AT", 1 },
 157         { "Maxtor 7213 AT", 1 },
 158         { "Maxtor 7245 AT", 1 },
 159         { "Maxtor 7345 AT", 1 },
 160         { "Maxtor 7546 AT", 3 },
 161         { "Maxtor 7540 AV", 3 },
 162
 163         { "SAMSUNG SHD-3121A", 1 },
 164         { "SAMSUNG SHD-3122A", 1 },
 165         { "SAMSUNG SHD-3172A", 1 },
 166
 167 /*      { "ST51080A", 4 },
 168  *      { "ST51270A", 4 },
 169  *      { "ST31220A", 4 },
 170  *      { "ST31640A", 4 },
 171  *      { "ST32140A", 4 },
 172  *      { "ST3780A",  4 },
 173  */
 174         { "ST5660A",  3 },
 175         { "ST3660A",  3 },
 176         { "ST3630A",  3 },
 177         { "ST3655A",  3 },
 178         { "ST3391A",  3 },
 179         { "ST3390A",  1 },
 180         { "ST3600A",  1 },
 181         { "ST3290A",  0 },
 182         { "ST3144A",  0 },
 183         { "ST3491A",  1 },      /* reports 3, should be 1 or 2 (depending on */
 184                                 /* drive) according to Seagates FIND-ATA program */
 185
 186         { "QUANTUM ELS127A", 0 },
 187         { "QUANTUM ELS170A", 0 },
 188         { "QUANTUM LPS240A", 0 },
 189         { "QUANTUM LPS210A", 3 },
 190         { "QUANTUM LPS270A", 3 },
 191         { "QUANTUM LPS365A", 3 },
 192         { "QUANTUM LPS540A", 3 },
 193         { "QUANTUM LIGHTNING 540A", 3 },
 194         { "QUANTUM LIGHTNING 730A", 3 },
 195
 196         { "QUANTUM FIREBALL_540", 3 }, /* Older Quantum Fireballs don't work */
 197         { "QUANTUM FIREBALL_640", 3 },
 198         { "QUANTUM FIREBALL_1080", 3 },
 199         { "QUANTUM FIREBALL_1280", 3 },
 200         { NULL, 0 }
 201 };
 202
 203 /**
 204  *      ide_scan_pio_blacklist  -       check for a blacklisted drive
 205  *      @model: Drive model string
 206  *
 207  *      This routine searches the ide_pio_blacklist for an entry
 208  *      matching the start/whole of the supplied model name.
 209  *
 210  *      Returns -1 if no match found.
 211  *      Otherwise returns the recommended PIO mode from ide_pio_blacklist[].
 212  */
 213
 214 static int ide_scan_pio_blacklist (char *model)
 215 {
 216         struct ide_pio_info *p;
 217
 218         for (p = ide_pio_blacklist; p->name != NULL; p++) {
 219                 if (strncmp(p->name, model, strlen(p->name)) == 0)
 220                         return p->pio;
 221         }
 222         return -1;
 223 }
 224
 225 unsigned int ide_pio_cycle_time(ide_drive_t *drive, u8 pio)
 226 {
 227         struct hd_driveid *id = drive->id;
 228         int cycle_time = 0;
 229
 230         if (id->field_valid & 2) {
 231                 if (id->capability & 8)
 232                         cycle_time = id->eide_pio_iordy;
 233                 else
 234                         cycle_time = id->eide_pio;
 235         }
 236
 237         /* conservative "downgrade" for all pre-ATA2 drives */
 238         if (pio < 3) {
 239                 if (cycle_time && cycle_time < ide_pio_timings[pio].cycle_time)
 240                         cycle_time = 0; /* use standard timing */
 241         }
 242
 243         return cycle_time ? cycle_time : ide_pio_timings[pio].cycle_time;
 244 }
 245
 246 EXPORT_SYMBOL_GPL(ide_pio_cycle_time);
 247
 248 /**
 249  *      ide_get_best_pio_mode   -       get PIO mode from drive
 250  *      @drive: drive to consider
 251  *      @mode_wanted: preferred mode
 252  *      @max_mode: highest allowed mode
 253  *
 254  *      This routine returns the recommended PIO settings for a given drive,
 255  *      based on the drive->id information and the ide_pio_blacklist[].
 256  *
 257  *      Drive PIO mode is auto-selected if 255 is passed as mode_wanted.
 258  *      This is used by most chipset support modules when "auto-tuning".
 259  */
 260
 261 u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
 262 {
 263         int pio_mode;
 264         struct hd_driveid* id = drive->id;
 265         int overridden  = 0;
 266
 267         if (mode_wanted != 255)
 268                 return min_t(u8, mode_wanted, max_mode);
 269
 270         if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0 &&
 271             (pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
 272                 printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
 273         } else {
 274                 pio_mode = id->tPIO;
 275                 if (pio_mode > 2) {     /* 2 is maximum allowed tPIO value */
 276                         pio_mode = 2;
 277                         overridden = 1;
 278                 }
 279                 if (id->field_valid & 2) {        /* drive implements ATA2? */
 280                         if (id->capability & 8) { /* IORDY supported? */
 281                                 if (id->eide_pio_modes & 7) {
 282                                         overridden = 0;
 283                                         if (id->eide_pio_modes & 4)
 284                                                 pio_mode = 5;
 285                                         else if (id->eide_pio_modes & 2)
 286                                                 pio_mode = 4;
 287                                         else
 288                                                 pio_mode = 3;
 289                                 }
 290                         }
 291                 }
 292
 293                 if (overridden)
 294                         printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
 295                                          drive->name);
 296
 297                 /*
 298                  * Conservative "downgrade" for all pre-ATA2 drives
 299                  */
 300                 if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_DOWNGRADE) == 0 &&
 301                     pio_mode && pio_mode < 4) {
 302                         pio_mode--;
 303                         printk(KERN_INFO "%s: applying conservative "
 304                                          "PIO \"downgrade\"\n", drive->name);
 305                 }
 306         }
 307
 308         if (pio_mode > max_mode)
 309                 pio_mode = max_mode;
 310
 311         return pio_mode;
 312 }
 313
 314 EXPORT_SYMBOL_GPL(ide_get_best_pio_mode);
 315
 316 /* req_pio == "255" for auto-tune */
 317 void ide_set_pio(ide_drive_t *drive, u8 req_pio)
 318 {
 319         ide_hwif_t *hwif = drive->hwif;
 320         u8 host_pio, pio;
 321
 322         if (hwif->set_pio_mode == NULL)
 323                 return;
 324
 325         BUG_ON(hwif->pio_mask == 0x00);
 326
 327         host_pio = fls(hwif->pio_mask) - 1;
 328
 329         pio = ide_get_best_pio_mode(drive, req_pio, host_pio);
 330
 331         /*
 332          * TODO:
 333          * - report device max PIO mode
 334          * - check req_pio != 255 against device max PIO mode
 335          */
 336         printk(KERN_DEBUG "%s: host max PIO%d wanted PIO%d%s selected PIO%d\n",
 337                           drive->name, host_pio, req_pio,
 338                           req_pio == 255 ? "(auto-tune)" : "", pio);
 339
 340         (void)ide_set_pio_mode(drive, XFER_PIO_0 + pio);
 341 }
 342
 343 EXPORT_SYMBOL_GPL(ide_set_pio);
 344
 345 /**
 346  *      ide_toggle_bounce       -       handle bounce buffering
 347  *      @drive: drive to update
 348  *      @on: on/off boolean
 349  *
 350  *      Enable or disable bounce buffering for the device. Drives move
 351  *      between PIO and DMA and that changes the rules we need.
 352  */
 353
 354 void ide_toggle_bounce(ide_drive_t *drive, int on)
 355 {
 356         u64 addr = BLK_BOUNCE_HIGH;     /* dma64_addr_t */
 357
 358         if (!PCI_DMA_BUS_IS_PHYS) {
 359                 addr = BLK_BOUNCE_ANY;
 360         } else if (on && drive->media == ide_disk) {
 361                 if (HWIF(drive)->pci_dev)
 362                         addr = HWIF(drive)->pci_dev->dma_mask;
 363         }
 364
 365         if (drive->queue)
 366                 blk_queue_bounce_limit(drive->queue, addr);
 367 }
 368
 369 int ide_set_pio_mode(ide_drive_t *drive, const u8 mode)
 370 {
 371         ide_hwif_t *hwif = drive->hwif;
 372
 373         if (hwif->set_pio_mode == NULL)
 374                 return -1;
 375
 376         /*
 377          * TODO: temporary hack for some legacy host drivers that didn't
 378          * set transfer mode on the device in ->set_pio_mode method...
 379          */
 380         if (hwif->set_dma_mode == NULL) {
 381                 hwif->set_pio_mode(drive, mode - XFER_PIO_0);
 382                 return 0;
 383         }
 384
 385         if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
 386                 if (ide_config_drive_speed(drive, mode))
 387                         return -1;
 388                 hwif->set_pio_mode(drive, mode - XFER_PIO_0);
 389                 return 0;
 390         } else {
 391                 hwif->set_pio_mode(drive, mode - XFER_PIO_0);
 392                 return ide_config_drive_speed(drive, mode);
 393         }
 394 }
 395
 396 int ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
 397 {
 398         ide_hwif_t *hwif = drive->hwif;
 399
 400         if (hwif->set_dma_mode == NULL)
 401                 return -1;
 402
 403         if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
 404                 if (ide_config_drive_speed(drive, mode))
 405                         return -1;
 406                 hwif->set_dma_mode(drive, mode);
 407                 return 0;
 408         } else {
 409                 hwif->set_dma_mode(drive, mode);
 410                 return ide_config_drive_speed(drive, mode);
 411         }
 412 }
 413
 414 EXPORT_SYMBOL_GPL(ide_set_dma_mode);
 415
 416 /**
 417  *      ide_set_xfer_rate       -       set transfer rate
 418  *      @drive: drive to set
 419  *      @rate: speed to attempt to set
 420  *
 421  *      General helper for setting the speed of an IDE device. This
 422  *      function knows about user enforced limits from the configuration
 423  *      which ->set_pio_mode/->set_dma_mode does not.
 424  */
 425
 426 int ide_set_xfer_rate(ide_drive_t *drive, u8 rate)
 427 {
 428         ide_hwif_t *hwif = drive->hwif;
 429
 430         if (hwif->set_dma_mode == NULL)
 431                 return -1;
 432
 433         rate = ide_rate_filter(drive, rate);
 434
 435         if (rate >= XFER_PIO_0 && rate <= XFER_PIO_5)
 436                 return ide_set_pio_mode(drive, rate);
 437
 438         /*
 439          * TODO: transfer modes 0x00-0x07 passed from the user-space are
 440          * currently handled here which needs fixing (please note that such
 441          * case could happen iff the transfer mode has already been set on
 442          * the device by ide-proc.c::set_xfer_rate()).
 443          */
 444
 445         return ide_set_dma_mode(drive, rate);
 446 }
 447
 448 static void ide_dump_opcode(ide_drive_t *drive)
 449 {
 450         struct request *rq;
 451         u8 opcode = 0;
 452         int found = 0;
 453
 454         spin_lock(&ide_lock);
 455         rq = NULL;
 456         if (HWGROUP(drive))
 457                 rq = HWGROUP(drive)->rq;
 458         spin_unlock(&ide_lock);
 459         if (!rq)
 460                 return;
 461         if (rq->cmd_type == REQ_TYPE_ATA_CMD ||
 462             rq->cmd_type == REQ_TYPE_ATA_TASK) {
 463                 char *args = rq->buffer;
 464                 if (args) {
 465                         opcode = args[0];
 466                         found = 1;
 467                 }
 468         } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
 469                 ide_task_t *args = rq->special;
 470                 if (args) {
 471                         task_struct_t *tf = (task_struct_t *) args->tfRegister;
 472                         opcode = tf->command;
 473                         found = 1;
 474                 }
 475         }
 476
 477         printk("ide: failed opcode was: ");
 478         if (!found)
 479                 printk("unknown\n");
 480         else
 481                 printk("0x%02x\n", opcode);
 482 }
 483
 484 static u8 ide_dump_ata_status(ide_drive_t *drive, const char *msg, u8 stat)
 485 {
 486         ide_hwif_t *hwif = HWIF(drive);
 487         unsigned long flags;
 488         u8 err = 0;
 489
 490         local_irq_save(flags);
 491         printk("%s: %s: status=0x%02x { ", drive->name, msg, stat);
 492         if (stat & BUSY_STAT)
 493                 printk("Busy ");
 494         else {
 495                 if (stat & READY_STAT)  printk("DriveReady ");
 496                 if (stat & WRERR_STAT)  printk("DeviceFault ");
 497                 if (stat & SEEK_STAT)   printk("SeekComplete ");
 498                 if (stat & DRQ_STAT)    printk("DataRequest ");
 499                 if (stat & ECC_STAT)    printk("CorrectedError ");
 500                 if (stat & INDEX_STAT)  printk("Index ");
 501                 if (stat & ERR_STAT)    printk("Error ");
 502         }
 503         printk("}\n");
 504         if ((stat & (BUSY_STAT|ERR_STAT)) == ERR_STAT) {
 505                 err = hwif->INB(IDE_ERROR_REG);
 506                 printk("%s: %s: error=0x%02x { ", drive->name, msg, err);
 507                 if (err & ABRT_ERR)     printk("DriveStatusError ");
 508                 if (err & ICRC_ERR)
 509                         printk((err & ABRT_ERR) ? "BadCRC " : "BadSector ");
 510                 if (err & ECC_ERR)      printk("UncorrectableError ");
 511                 if (err & ID_ERR)       printk("SectorIdNotFound ");
 512                 if (err & TRK0_ERR)     printk("TrackZeroNotFound ");
 513                 if (err & MARK_ERR)     printk("AddrMarkNotFound ");
 514                 printk("}");
 515                 if ((err & (BBD_ERR | ABRT_ERR)) == BBD_ERR ||
 516                     (err & (ECC_ERR|ID_ERR|MARK_ERR))) {
 517                         if (drive->addressing == 1) {
 518                                 __u64 sectors = 0;
 519                                 u32 low = 0, high = 0;
 520                                 hwif->OUTB(drive->ctl&~0x80, IDE_CONTROL_REG);
 521                                 low = ide_read_24(drive);
 522                                 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
 523                                 high = ide_read_24(drive);
 524                                 sectors = ((__u64)high << 24) | low;
 525                                 printk(", LBAsect=%llu, high=%d, low=%d",
 526                                        (unsigned long long) sectors,
 527                                        high, low);
 528                         } else {
 529                                 u8 cur = hwif->INB(IDE_SELECT_REG);
 530                                 if (cur & 0x40) {       /* using LBA? */
 531                                         printk(", LBAsect=%ld", (unsigned long)
 532                                          ((cur&0xf)<<24)
 533                                          |(hwif->INB(IDE_HCYL_REG)<<16)
 534                                          |(hwif->INB(IDE_LCYL_REG)<<8)
 535                                          | hwif->INB(IDE_SECTOR_REG));
 536                                 } else {
 537                                         printk(", CHS=%d/%d/%d",
 538                                          (hwif->INB(IDE_HCYL_REG)<<8) +
 539                                           hwif->INB(IDE_LCYL_REG),
 540                                           cur & 0xf,
 541                                           hwif->INB(IDE_SECTOR_REG));
 542                                 }
 543                         }
 544                         if (HWGROUP(drive) && HWGROUP(drive)->rq)
 545                                 printk(", sector=%llu",
 546                                         (unsigned long long)HWGROUP(drive)->rq->sector);
 547                 }
 548                 printk("\n");
 549         }
 550         ide_dump_opcode(drive);
 551         local_irq_restore(flags);
 552         return err;
 553 }
 554
 555 /**
 556  *      ide_dump_atapi_status       -       print human readable atapi status
 557  *      @drive: drive that status applies to
 558  *      @msg: text message to print
 559  *      @stat: status byte to decode
 560  *
 561  *      Error reporting, in human readable form (luxurious, but a memory hog).
 562  */
 563
 564 static u8 ide_dump_atapi_status(ide_drive_t *drive, const char *msg, u8 stat)
 565 {
 566         unsigned long flags;
 567
 568         atapi_status_t status;
 569         atapi_error_t error;
 570
 571         status.all = stat;
 572         error.all = 0;
 573         local_irq_save(flags);
 574         printk("%s: %s: status=0x%02x { ", drive->name, msg, stat);
 575         if (status.b.bsy)
 576                 printk("Busy ");
 577         else {
 578                 if (status.b.drdy)      printk("DriveReady ");
 579                 if (status.b.df)        printk("DeviceFault ");
 580                 if (status.b.dsc)       printk("SeekComplete ");
 581                 if (status.b.drq)       printk("DataRequest ");
 582                 if (status.b.corr)      printk("CorrectedError ");
 583                 if (status.b.idx)       printk("Index ");
 584                 if (status.b.check)     printk("Error ");
 585         }
 586         printk("}\n");
 587         if (status.b.check && !status.b.bsy) {
 588                 error.all = HWIF(drive)->INB(IDE_ERROR_REG);
 589                 printk("%s: %s: error=0x%02x { ", drive->name, msg, error.all);
 590                 if (error.b.ili)        printk("IllegalLengthIndication ");
 591                 if (error.b.eom)        printk("EndOfMedia ");
 592                 if (error.b.abrt)       printk("AbortedCommand ");
 593                 if (error.b.mcr)        printk("MediaChangeRequested ");
 594                 if (error.b.sense_key)  printk("LastFailedSense=0x%02x ",
 595                                                 error.b.sense_key);
 596                 printk("}\n");
 597         }
 598         ide_dump_opcode(drive);
 599         local_irq_restore(flags);
 600         return error.all;
 601 }
 602
 603 /**
 604  *      ide_dump_status         -       translate ATA/ATAPI error
 605  *      @drive: drive the error occured on
 606  *      @msg: information string
 607  *      @stat: status byte
 608  *
 609  *      Error reporting, in human readable form (luxurious, but a memory hog).
 610  *      Combines the drive name, message and status byte to provide a
 611  *      user understandable explanation of the device error.
 612  */
 613
 614 u8 ide_dump_status(ide_drive_t *drive, const char *msg, u8 stat)
 615 {
 616         if (drive->media == ide_disk)
 617                 return ide_dump_ata_status(drive, msg, stat);
 618         return ide_dump_atapi_status(drive, msg, stat);
 619 }
 620
 621 EXPORT_SYMBOL(ide_dump_status);