drivers/ide/ide-acpi.c

   1 /*
   2  * ide-acpi.c
   3  * Provides ACPI support for IDE drives.
   4  *
   5  * Copyright (C) 2005 Intel Corp.
   6  * Copyright (C) 2005 Randy Dunlap
   7  * Copyright (C) 2006 SUSE Linux Products GmbH
   8  * Copyright (C) 2006 Hannes Reinecke
   9  */
  10
  11 #include <linux/ata.h>
  12 #include <linux/delay.h>
  13 #include <linux/device.h>
  14 #include <linux/errno.h>
  15 #include <linux/kernel.h>
  16 #include <acpi/acpi.h>
  17 #include <linux/ide.h>
  18 #include <linux/pci.h>
  19 #include <linux/dmi.h>
  20
  21 #include <acpi/acpi_bus.h>
  22 #include <acpi/acnames.h>
  23 #include <acpi/acnamesp.h>
  24 #include <acpi/acparser.h>
  25 #include <acpi/acexcep.h>
  26 #include <acpi/acmacros.h>
  27 #include <acpi/actypes.h>
  28
  29 #define REGS_PER_GTF            7
  30 struct taskfile_array {
  31         u8      tfa[REGS_PER_GTF];      /* regs. 0x1f1 - 0x1f7 */
  32 };
  33
  34 struct GTM_buffer {
  35         u32     PIO_speed0;
  36         u32     DMA_speed0;
  37         u32     PIO_speed1;
  38         u32     DMA_speed1;
  39         u32     GTM_flags;
  40 };
  41
  42 struct ide_acpi_drive_link {
  43         ide_drive_t     *drive;
  44         acpi_handle      obj_handle;
  45         u8               idbuff[512];
  46 };
  47
  48 struct ide_acpi_hwif_link {
  49         ide_hwif_t                      *hwif;
  50         acpi_handle                      obj_handle;
  51         struct GTM_buffer                gtm;
  52         struct ide_acpi_drive_link       master;
  53         struct ide_acpi_drive_link       slave;
  54 };
  55
  56 #undef DEBUGGING
  57 /* note: adds function name and KERN_DEBUG */
  58 #ifdef DEBUGGING
  59 #define DEBPRINT(fmt, args...)  \
  60                 printk(KERN_DEBUG "%s: " fmt, __FUNCTION__, ## args)
  61 #else
  62 #define DEBPRINT(fmt, args...)  do {} while (0)
  63 #endif  /* DEBUGGING */
  64
  65 extern int ide_noacpi;
  66 extern int ide_noacpitfs;
  67 extern int ide_noacpionboot;
  68
  69 static bool ide_noacpi_psx;
  70 static int no_acpi_psx(const struct dmi_system_id *id)
  71 {
  72         ide_noacpi_psx = true;
  73         printk(KERN_NOTICE"%s detected - disable ACPI _PSx.\n", id->ident);
  74         return 0;
  75 }
  76
  77 static const struct dmi_system_id ide_acpi_dmi_table[] = {
  78         /* Bug 9673. */
  79         /* We should check if this is because ACPI NVS isn't save/restored. */
  80         {
  81                 .callback = no_acpi_psx,
  82                 .ident    = "HP nx9005",
  83                 .matches  = {
  84                         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies Ltd."),
  85                         DMI_MATCH(DMI_BIOS_VERSION, "KAM1.60")
  86                 },
  87         },
  88
  89         { }     /* terminate list */
  90 };
  91
  92 static int ide_acpi_blacklist(void)
  93 {
  94         static int done;
  95         if (done)
  96                 return 0;
  97         done = 1;
  98         dmi_check_system(ide_acpi_dmi_table);
  99         return 0;
 100 }
 101
 102 /**
 103  * ide_get_dev_handle - finds acpi_handle and PCI device.function
 104  * @dev: device to locate
 105  * @handle: returned acpi_handle for @dev
 106  * @pcidevfn: return PCI device.func for @dev
 107  *
 108  * Returns the ACPI object handle to the corresponding PCI device.
 109  *
 110  * Returns 0 on success, <0 on error.
 111  */
 112 static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
 113                                acpi_integer *pcidevfn)
 114 {
 115         struct pci_dev *pdev = to_pci_dev(dev);
 116         unsigned int bus, devnum, func;
 117         acpi_integer addr;
 118         acpi_handle dev_handle;
 119         struct acpi_buffer buffer = {.length = ACPI_ALLOCATE_BUFFER,
 120                                         .pointer = NULL};
 121         acpi_status status;
 122         struct acpi_device_info *dinfo = NULL;
 123         int ret = -ENODEV;
 124
 125         bus = pdev->bus->number;
 126         devnum = PCI_SLOT(pdev->devfn);
 127         func = PCI_FUNC(pdev->devfn);
 128         /* ACPI _ADR encoding for PCI bus: */
 129         addr = (acpi_integer)(devnum << 16 | func);
 130
 131         DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
 132
 133         dev_handle = DEVICE_ACPI_HANDLE(dev);
 134         if (!dev_handle) {
 135                 DEBPRINT("no acpi handle for device\n");
 136                 goto err;
 137         }
 138
 139         status = acpi_get_object_info(dev_handle, &buffer);
 140         if (ACPI_FAILURE(status)) {
 141                 DEBPRINT("get_object_info for device failed\n");
 142                 goto err;
 143         }
 144         dinfo = buffer.pointer;
 145         if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
 146             dinfo->address == addr) {
 147                 *pcidevfn = addr;
 148                 *handle = dev_handle;
 149         } else {
 150                 DEBPRINT("get_object_info for device has wrong "
 151                         " address: %llu, should be %u\n",
 152                         dinfo ? (unsigned long long)dinfo->address : -1ULL,
 153                         (unsigned int)addr);
 154                 goto err;
 155         }
 156
 157         DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
 158                  devnum, func, (unsigned long long)addr, *handle);
 159         ret = 0;
 160 err:
 161         kfree(dinfo);
 162         return ret;
 163 }
 164
 165 /**
 166  * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
 167  * @hwif: device to locate
 168  *
 169  * Retrieves the object handle for a given hwif.
 170  *
 171  * Returns handle on success, 0 on error.
 172  */
 173 static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
 174 {
 175         struct device           *dev = hwif->gendev.parent;
 176         acpi_handle             dev_handle;
 177         acpi_integer            pcidevfn;
 178         acpi_handle             chan_handle;
 179         int                     err;
 180
 181         DEBPRINT("ENTER: device %s\n", hwif->name);
 182
 183         if (!dev) {
 184                 DEBPRINT("no PCI device for %s\n", hwif->name);
 185                 return NULL;
 186         }
 187
 188         err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
 189         if (err < 0) {
 190                 DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
 191                 return NULL;
 192         }
 193
 194         /* get child objects of dev_handle == channel objects,
 195          * + _their_ children == drive objects */
 196         /* channel is hwif->channel */
 197         chan_handle = acpi_get_child(dev_handle, hwif->channel);
 198         DEBPRINT("chan adr=%d: handle=0x%p\n",
 199                  hwif->channel, chan_handle);
 200
 201         return chan_handle;
 202 }
 203
 204 /**
 205  * ide_acpi_drive_get_handle - Get ACPI object handle for a given drive
 206  * @drive: device to locate
 207  *
 208  * Retrieves the object handle of a given drive. According to the ACPI
 209  * spec the drive is a child of the hwif.
 210  *
 211  * Returns handle on success, 0 on error.
 212  */
 213 static acpi_handle ide_acpi_drive_get_handle(ide_drive_t *drive)
 214 {
 215         ide_hwif_t      *hwif = HWIF(drive);
 216         int              port;
 217         acpi_handle      drive_handle;
 218
 219         if (!hwif->acpidata)
 220                 return NULL;
 221
 222         if (!hwif->acpidata->obj_handle)
 223                 return NULL;
 224
 225         port = hwif->channel ? drive->dn - 2: drive->dn;
 226
 227         DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
 228                  drive->name, hwif->channel, port);
 229
 230
 231         /* TBD: could also check ACPI object VALID bits */
 232         drive_handle = acpi_get_child(hwif->acpidata->obj_handle, port);
 233         DEBPRINT("drive %s handle 0x%p\n", drive->name, drive_handle);
 234
 235         return drive_handle;
 236 }
 237
 238 /**
 239  * do_drive_get_GTF - get the drive bootup default taskfile settings
 240  * @drive: the drive for which the taskfile settings should be retrieved
 241  * @gtf_length: number of bytes of _GTF data returned at @gtf_address
 242  * @gtf_address: buffer containing _GTF taskfile arrays
 243  *
 244  * The _GTF method has no input parameters.
 245  * It returns a variable number of register set values (registers
 246  * hex 1F1..1F7, taskfiles).
 247  * The <variable number> is not known in advance, so have ACPI-CA
 248  * allocate the buffer as needed and return it, then free it later.
 249  *
 250  * The returned @gtf_length and @gtf_address are only valid if the
 251  * function return value is 0.
 252  */
 253 static int do_drive_get_GTF(ide_drive_t *drive,
 254                      unsigned int *gtf_length, unsigned long *gtf_address,
 255                      unsigned long *obj_loc)
 256 {
 257         acpi_status                     status;
 258         struct acpi_buffer              output;
 259         union acpi_object               *out_obj;
 260         ide_hwif_t                      *hwif = HWIF(drive);
 261         struct device                   *dev = hwif->gendev.parent;
 262         int                             err = -ENODEV;
 263         int                             port;
 264
 265         *gtf_length = 0;
 266         *gtf_address = 0UL;
 267         *obj_loc = 0UL;
 268
 269         if (ide_noacpi)
 270                 return 0;
 271
 272         if (!dev) {
 273                 DEBPRINT("no PCI device for %s\n", hwif->name);
 274                 goto out;
 275         }
 276
 277         if (!hwif->acpidata) {
 278                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 279                 goto out;
 280         }
 281
 282         port = hwif->channel ? drive->dn - 2: drive->dn;
 283
 284         if (!drive->acpidata) {
 285                 if (port == 0) {
 286                         drive->acpidata = &hwif->acpidata->master;
 287                         hwif->acpidata->master.drive = drive;
 288                 } else {
 289                         drive->acpidata = &hwif->acpidata->slave;
 290                         hwif->acpidata->slave.drive = drive;
 291                 }
 292         }
 293
 294         DEBPRINT("ENTER: %s at %s, port#: %d, hard_port#: %d\n",
 295                  hwif->name, dev->bus_id, port, hwif->channel);
 296
 297         if (!drive->present) {
 298                 DEBPRINT("%s drive %d:%d not present\n",
 299                          hwif->name, hwif->channel, port);
 300                 goto out;
 301         }
 302
 303         /* Get this drive's _ADR info. if not already known. */
 304         if (!drive->acpidata->obj_handle) {
 305                 drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
 306                 if (!drive->acpidata->obj_handle) {
 307                         DEBPRINT("No ACPI object found for %s\n",
 308                                  drive->name);
 309                         goto out;
 310                 }
 311         }
 312
 313         /* Setting up output buffer */
 314         output.length = ACPI_ALLOCATE_BUFFER;
 315         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 316
 317         /* _GTF has no input parameters */
 318         err = -EIO;
 319         status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
 320                                       NULL, &output);
 321         if (ACPI_FAILURE(status)) {
 322                 printk(KERN_DEBUG
 323                        "%s: Run _GTF error: status = 0x%x\n",
 324                        __FUNCTION__, status);
 325                 goto out;
 326         }
 327
 328         if (!output.length || !output.pointer) {
 329                 DEBPRINT("Run _GTF: "
 330                        "length or ptr is NULL (0x%llx, 0x%p)\n",
 331                        (unsigned long long)output.length,
 332                        output.pointer);
 333                 goto out;
 334         }
 335
 336         out_obj = output.pointer;
 337         if (out_obj->type != ACPI_TYPE_BUFFER) {
 338                 DEBPRINT("Run _GTF: error: "
 339                        "expected object type of ACPI_TYPE_BUFFER, "
 340                        "got 0x%x\n", out_obj->type);
 341                 err = -ENOENT;
 342                 kfree(output.pointer);
 343                 goto out;
 344         }
 345
 346         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 347             out_obj->buffer.length % REGS_PER_GTF) {
 348                 printk(KERN_ERR
 349                        "%s: unexpected GTF length (%d) or addr (0x%p)\n",
 350                        __FUNCTION__, out_obj->buffer.length,
 351                        out_obj->buffer.pointer);
 352                 err = -ENOENT;
 353                 kfree(output.pointer);
 354                 goto out;
 355         }
 356
 357         *gtf_length = out_obj->buffer.length;
 358         *gtf_address = (unsigned long)out_obj->buffer.pointer;
 359         *obj_loc = (unsigned long)out_obj;
 360         DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
 361                  *gtf_length, *gtf_address, *obj_loc);
 362         err = 0;
 363 out:
 364         return err;
 365 }
 366
 367 /**
 368  * taskfile_load_raw - send taskfile registers to drive
 369  * @drive: drive to which output is sent
 370  * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
 371  *
 372  * Outputs IDE taskfile to the drive.
 373  */
 374 static int taskfile_load_raw(ide_drive_t *drive,
 375                               const struct taskfile_array *gtf)
 376 {
 377         ide_task_t args;
 378         int err = 0;
 379
 380         DEBPRINT("(0x1f1-1f7): hex: "
 381                "%02x %02x %02x %02x %02x %02x %02x\n",
 382                gtf->tfa[0], gtf->tfa[1], gtf->tfa[2],
 383                gtf->tfa[3], gtf->tfa[4], gtf->tfa[5], gtf->tfa[6]);
 384
 385         memset(&args, 0, sizeof(ide_task_t));
 386
 387         /* convert gtf to IDE Taskfile */
 388         memcpy(&args.tf_array[7], &gtf->tfa, 7);
 389
 390         if (ide_noacpitfs) {
 391                 DEBPRINT("_GTF execution disabled\n");
 392                 return err;
 393         }
 394
 395         err = ide_no_data_taskfile(drive, &args);
 396         if (err)
 397                 printk(KERN_ERR "%s: ide_no_data_taskfile failed: %u\n",
 398                        __FUNCTION__, err);
 399
 400         return err;
 401 }
 402
 403 /**
 404  * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
 405  * @drive: the drive to which the taskfile command should be sent
 406  * @gtf_length: total number of bytes of _GTF taskfiles
 407  * @gtf_address: location of _GTF taskfile arrays
 408  *
 409  * Write {gtf_address, length gtf_length} in groups of
 410  * REGS_PER_GTF bytes.
 411  */
 412 static int do_drive_set_taskfiles(ide_drive_t *drive,
 413                                   unsigned int gtf_length,
 414                                   unsigned long gtf_address)
 415 {
 416         int                     rc = -ENODEV, err;
 417         int                     gtf_count = gtf_length / REGS_PER_GTF;
 418         int                     ix;
 419         struct taskfile_array   *gtf;
 420
 421         if (ide_noacpi)
 422                 return 0;
 423
 424         DEBPRINT("ENTER: %s, hard_port#: %d\n", drive->name, drive->dn);
 425
 426         if (!drive->present)
 427                 goto out;
 428         if (!gtf_count)         /* shouldn't be here */
 429                 goto out;
 430
 431         DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
 432                  gtf_length, gtf_length, gtf_count, gtf_address);
 433
 434         if (gtf_length % REGS_PER_GTF) {
 435                 printk(KERN_ERR "%s: unexpected GTF length (%d)\n",
 436                        __FUNCTION__, gtf_length);
 437                 goto out;
 438         }
 439
 440         rc = 0;
 441         for (ix = 0; ix < gtf_count; ix++) {
 442                 gtf = (struct taskfile_array *)
 443                         (gtf_address + ix * REGS_PER_GTF);
 444
 445                 /* send all TaskFile registers (0x1f1-0x1f7) *in*that*order* */
 446                 err = taskfile_load_raw(drive, gtf);
 447                 if (err)
 448                         rc = err;
 449         }
 450
 451 out:
 452         return rc;
 453 }
 454
 455 /**
 456  * ide_acpi_exec_tfs - get then write drive taskfile settings
 457  * @drive: the drive for which the taskfile settings should be
 458  *         written.
 459  *
 460  * According to the ACPI spec this should be called after _STM
 461  * has been evaluated for the interface. Some ACPI vendors interpret
 462  * that as a hard requirement and modify the taskfile according
 463  * to the Identify Drive information passed down with _STM.
 464  * So one should really make sure to call this only after _STM has
 465  * been executed.
 466  */
 467 int ide_acpi_exec_tfs(ide_drive_t *drive)
 468 {
 469         int             ret;
 470         unsigned int    gtf_length;
 471         unsigned long   gtf_address;
 472         unsigned long   obj_loc;
 473
 474         if (ide_noacpi)
 475                 return 0;
 476
 477         DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
 478
 479         ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
 480         if (ret < 0) {
 481                 DEBPRINT("get_GTF error (%d)\n", ret);
 482                 return ret;
 483         }
 484
 485         DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
 486
 487         ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
 488         kfree((void *)obj_loc);
 489         if (ret < 0) {
 490                 DEBPRINT("set_taskfiles error (%d)\n", ret);
 491         }
 492
 493         DEBPRINT("ret=%d\n", ret);
 494
 495         return ret;
 496 }
 497 EXPORT_SYMBOL_GPL(ide_acpi_exec_tfs);
 498
 499 /**
 500  * ide_acpi_get_timing - get the channel (controller) timings
 501  * @hwif: target IDE interface (channel)
 502  *
 503  * This function executes the _GTM ACPI method for the target channel.
 504  *
 505  */
 506 void ide_acpi_get_timing(ide_hwif_t *hwif)
 507 {
 508         acpi_status             status;
 509         struct acpi_buffer      output;
 510         union acpi_object       *out_obj;
 511
 512         if (ide_noacpi)
 513                 return;
 514
 515         DEBPRINT("ENTER:\n");
 516
 517         if (!hwif->acpidata) {
 518                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 519                 return;
 520         }
 521
 522         /* Setting up output buffer for _GTM */
 523         output.length = ACPI_ALLOCATE_BUFFER;
 524         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 525
 526         /* _GTM has no input parameters */
 527         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
 528                                       NULL, &output);
 529
 530         DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
 531                  status, output.pointer,
 532                  (unsigned long long)output.length);
 533
 534         if (ACPI_FAILURE(status)) {
 535                 DEBPRINT("Run _GTM error: status = 0x%x\n", status);
 536                 return;
 537         }
 538
 539         if (!output.length || !output.pointer) {
 540                 DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
 541                        (unsigned long long)output.length,
 542                        output.pointer);
 543                 kfree(output.pointer);
 544                 return;
 545         }
 546
 547         out_obj = output.pointer;
 548         if (out_obj->type != ACPI_TYPE_BUFFER) {
 549                 kfree(output.pointer);
 550                 DEBPRINT("Run _GTM: error: "
 551                        "expected object type of ACPI_TYPE_BUFFER, "
 552                        "got 0x%x\n", out_obj->type);
 553                 return;
 554         }
 555
 556         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 557             out_obj->buffer.length != sizeof(struct GTM_buffer)) {
 558                 kfree(output.pointer);
 559                 printk(KERN_ERR
 560                         "%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
 561                         "addr (0x%p)\n",
 562                         __FUNCTION__, out_obj->buffer.length,
 563                         sizeof(struct GTM_buffer), out_obj->buffer.pointer);
 564                 return;
 565         }
 566
 567         memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
 568                sizeof(struct GTM_buffer));
 569
 570         DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
 571                  out_obj->buffer.pointer, out_obj->buffer.length,
 572                  sizeof(struct GTM_buffer));
 573
 574         DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
 575                  hwif->acpidata->gtm.PIO_speed0,
 576                  hwif->acpidata->gtm.DMA_speed0,
 577                  hwif->acpidata->gtm.PIO_speed1,
 578                  hwif->acpidata->gtm.DMA_speed1,
 579                  hwif->acpidata->gtm.GTM_flags);
 580
 581         kfree(output.pointer);
 582 }
 583 EXPORT_SYMBOL_GPL(ide_acpi_get_timing);
 584
 585 /**
 586  * ide_acpi_push_timing - set the channel (controller) timings
 587  * @hwif: target IDE interface (channel)
 588  *
 589  * This function executes the _STM ACPI method for the target channel.
 590  *
 591  * _STM requires Identify Drive data, which has to passed as an argument.
 592  * Unfortunately hd_driveid is a mangled version which we can't readily
 593  * use; hence we'll get the information afresh.
 594  */
 595 void ide_acpi_push_timing(ide_hwif_t *hwif)
 596 {
 597         acpi_status             status;
 598         struct acpi_object_list input;
 599         union acpi_object       in_params[3];
 600         struct ide_acpi_drive_link      *master = &hwif->acpidata->master;
 601         struct ide_acpi_drive_link      *slave = &hwif->acpidata->slave;
 602
 603         if (ide_noacpi)
 604                 return;
 605
 606         DEBPRINT("ENTER:\n");
 607
 608         if (!hwif->acpidata) {
 609                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 610                 return;
 611         }
 612
 613         /* Give the GTM buffer + drive Identify data to the channel via the
 614          * _STM method: */
 615         /* setup input parameters buffer for _STM */
 616         input.count = 3;
 617         input.pointer = in_params;
 618         in_params[0].type = ACPI_TYPE_BUFFER;
 619         in_params[0].buffer.length = sizeof(struct GTM_buffer);
 620         in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
 621         in_params[1].type = ACPI_TYPE_BUFFER;
 622         in_params[1].buffer.length = sizeof(struct hd_driveid);
 623         in_params[1].buffer.pointer = (u8 *)&master->idbuff;
 624         in_params[2].type = ACPI_TYPE_BUFFER;
 625         in_params[2].buffer.length = sizeof(struct hd_driveid);
 626         in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
 627         /* Output buffer: _STM has no output */
 628
 629         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
 630                                       &input, NULL);
 631
 632         if (ACPI_FAILURE(status)) {
 633                 DEBPRINT("Run _STM error: status = 0x%x\n", status);
 634         }
 635         DEBPRINT("_STM status: %d\n", status);
 636 }
 637 EXPORT_SYMBOL_GPL(ide_acpi_push_timing);
 638
 639 /**
 640  * ide_acpi_set_state - set the channel power state
 641  * @hwif: target IDE interface
 642  * @on: state, on/off
 643  *
 644  * This function executes the _PS0/_PS3 ACPI method to set the power state.
 645  * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
 646  */
 647 void ide_acpi_set_state(ide_hwif_t *hwif, int on)
 648 {
 649         int unit;
 650
 651         if (ide_noacpi || ide_noacpi_psx)
 652                 return;
 653
 654         DEBPRINT("ENTER:\n");
 655
 656         if (!hwif->acpidata) {
 657                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 658                 return;
 659         }
 660         /* channel first and then drives for power on and verse versa for power off */
 661         if (on)
 662                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
 663         for (unit = 0; unit < MAX_DRIVES; ++unit) {
 664                 ide_drive_t *drive = &hwif->drives[unit];
 665
 666                 if (!drive->acpidata->obj_handle)
 667                         drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
 668
 669                 if (drive->acpidata->obj_handle && drive->present) {
 670                         acpi_bus_set_power(drive->acpidata->obj_handle,
 671                                 on? ACPI_STATE_D0: ACPI_STATE_D3);
 672                 }
 673         }
 674         if (!on)
 675                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D3);
 676 }
 677
 678 /**
 679  * ide_acpi_init - initialize the ACPI link for an IDE interface
 680  * @hwif: target IDE interface (channel)
 681  *
 682  * The ACPI spec is not quite clear when the drive identify buffer
 683  * should be obtained. Calling IDENTIFY DEVICE during shutdown
 684  * is not the best of ideas as the drive might already being put to
 685  * sleep. And obviously we can't call it during resume.
 686  * So we get the information during startup; but this means that
 687  * any changes during run-time will be lost after resume.
 688  */
 689 void ide_acpi_init(ide_hwif_t *hwif)
 690 {
 691         int unit;
 692         int                     err;
 693         struct ide_acpi_drive_link      *master;
 694         struct ide_acpi_drive_link      *slave;
 695
 696         ide_acpi_blacklist();
 697
 698         hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
 699         if (!hwif->acpidata)
 700                 return;
 701
 702         hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
 703         if (!hwif->acpidata->obj_handle) {
 704                 DEBPRINT("no ACPI object for %s found\n", hwif->name);
 705                 kfree(hwif->acpidata);
 706                 hwif->acpidata = NULL;
 707                 return;
 708         }
 709
 710         /*
 711          * The ACPI spec mandates that we send information
 712          * for both drives, regardless whether they are connected
 713          * or not.
 714          */
 715         hwif->acpidata->master.drive = &hwif->drives[0];
 716         hwif->drives[0].acpidata = &hwif->acpidata->master;
 717         master = &hwif->acpidata->master;
 718
 719         hwif->acpidata->slave.drive = &hwif->drives[1];
 720         hwif->drives[1].acpidata = &hwif->acpidata->slave;
 721         slave = &hwif->acpidata->slave;
 722
 723
 724         /*
 725          * Send IDENTIFY for each drive
 726          */
 727         if (master->drive->present) {
 728                 err = taskfile_lib_get_identify(master->drive, master->idbuff);
 729                 if (err) {
 730                         DEBPRINT("identify device %s failed (%d)\n",
 731                                  master->drive->name, err);
 732                 }
 733         }
 734
 735         if (slave->drive->present) {
 736                 err = taskfile_lib_get_identify(slave->drive, slave->idbuff);
 737                 if (err) {
 738                         DEBPRINT("identify device %s failed (%d)\n",
 739                                  slave->drive->name, err);
 740                 }
 741         }
 742
 743         if (ide_noacpionboot) {
 744                 DEBPRINT("ACPI methods disabled on boot\n");
 745                 return;
 746         }
 747
 748         /* ACPI _PS0 before _STM */
 749         ide_acpi_set_state(hwif, 1);
 750         /*
 751          * ACPI requires us to call _STM on startup
 752          */
 753         ide_acpi_get_timing(hwif);
 754         ide_acpi_push_timing(hwif);
 755
 756         for (unit = 0; unit < MAX_DRIVES; ++unit) {
 757                 ide_drive_t *drive = &hwif->drives[unit];
 758
 759                 if (drive->present) {
 760                         /* Execute ACPI startup code */
 761                         ide_acpi_exec_tfs(drive);
 762                 }
 763         }
 764 }
 765 EXPORT_SYMBOL_GPL(ide_acpi_init);