SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/ide/ide-acpi.c

   1 /*
   2  * Provides ACPI support for IDE drives.
   3  *
   4  * Copyright (C) 2005 Intel Corp.
   5  * Copyright (C) 2005 Randy Dunlap
   6  * Copyright (C) 2006 SUSE Linux Products GmbH
   7  * Copyright (C) 2006 Hannes Reinecke
   8  */
   9
  10 #include <linux/ata.h>
  11 #include <linux/delay.h>
  12 #include <linux/device.h>
  13 #include <linux/errno.h>
  14 #include <linux/kernel.h>
  15 #include <acpi/acpi.h>
  16 #include <linux/ide.h>
  17 #include <linux/pci.h>
  18 #include <linux/dmi.h>
  19
  20 #include <acpi/acpi_bus.h>
  21
  22 #define REGS_PER_GTF            7
  23 struct taskfile_array {
  24         u8      tfa[REGS_PER_GTF];      /* regs. 0x1f1 - 0x1f7 */
  25 };
  26
  27 struct GTM_buffer {
  28         u32     PIO_speed0;
  29         u32     DMA_speed0;
  30         u32     PIO_speed1;
  31         u32     DMA_speed1;
  32         u32     GTM_flags;
  33 };
  34
  35 struct ide_acpi_drive_link {
  36         acpi_handle      obj_handle;
  37         u8               idbuff[512];
  38 };
  39
  40 struct ide_acpi_hwif_link {
  41         ide_hwif_t                      *hwif;
  42         acpi_handle                      obj_handle;
  43         struct GTM_buffer                gtm;
  44         struct ide_acpi_drive_link       master;
  45         struct ide_acpi_drive_link       slave;
  46 };
  47
  48 #undef DEBUGGING
  49 /* note: adds function name and KERN_DEBUG */
  50 #ifdef DEBUGGING
  51 #define DEBPRINT(fmt, args...)  \
  52                 printk(KERN_DEBUG "%s: " fmt, __func__, ## args)
  53 #else
  54 #define DEBPRINT(fmt, args...)  do {} while (0)
  55 #endif  /* DEBUGGING */
  56
  57 static int ide_noacpi;
  58 module_param_named(noacpi, ide_noacpi, bool, 0);
  59 MODULE_PARM_DESC(noacpi, "disable IDE ACPI support");
  60
  61 static int ide_acpigtf;
  62 module_param_named(acpigtf, ide_acpigtf, bool, 0);
  63 MODULE_PARM_DESC(acpigtf, "enable IDE ACPI _GTF support");
  64
  65 static int ide_acpionboot;
  66 module_param_named(acpionboot, ide_acpionboot, bool, 0);
  67 MODULE_PARM_DESC(acpionboot, "call IDE ACPI methods on boot");
  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             uninitialized_var(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  * do_drive_get_GTF - get the drive bootup default taskfile settings
 206  * @drive: the drive for which the taskfile settings should be retrieved
 207  * @gtf_length: number of bytes of _GTF data returned at @gtf_address
 208  * @gtf_address: buffer containing _GTF taskfile arrays
 209  *
 210  * The _GTF method has no input parameters.
 211  * It returns a variable number of register set values (registers
 212  * hex 1F1..1F7, taskfiles).
 213  * The <variable number> is not known in advance, so have ACPI-CA
 214  * allocate the buffer as needed and return it, then free it later.
 215  *
 216  * The returned @gtf_length and @gtf_address are only valid if the
 217  * function return value is 0.
 218  */
 219 static int do_drive_get_GTF(ide_drive_t *drive,
 220                      unsigned int *gtf_length, unsigned long *gtf_address,
 221                      unsigned long *obj_loc)
 222 {
 223         acpi_status                     status;
 224         struct acpi_buffer              output;
 225         union acpi_object               *out_obj;
 226         ide_hwif_t                      *hwif = drive->hwif;
 227         struct device                   *dev = hwif->gendev.parent;
 228         int                             err = -ENODEV;
 229         int                             port;
 230
 231         *gtf_length = 0;
 232         *gtf_address = 0UL;
 233         *obj_loc = 0UL;
 234
 235         if (ide_noacpi)
 236                 return 0;
 237
 238         if (!dev) {
 239                 DEBPRINT("no PCI device for %s\n", hwif->name);
 240                 goto out;
 241         }
 242
 243         if (!hwif->acpidata) {
 244                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 245                 goto out;
 246         }
 247
 248         port = hwif->channel ? drive->dn - 2: drive->dn;
 249
 250         DEBPRINT("ENTER: %s at %s, port#: %d, hard_port#: %d\n",
 251                  hwif->name, dev_name(dev), port, hwif->channel);
 252
 253         if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0) {
 254                 DEBPRINT("%s drive %d:%d not present\n",
 255                          hwif->name, hwif->channel, port);
 256                 goto out;
 257         }
 258
 259         if (!drive->acpidata->obj_handle) {
 260                 DEBPRINT("No ACPI object found for %s\n", drive->name);
 261                 goto out;
 262         }
 263
 264         /* Setting up output buffer */
 265         output.length = ACPI_ALLOCATE_BUFFER;
 266         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 267
 268         /* _GTF has no input parameters */
 269         err = -EIO;
 270         status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
 271                                       NULL, &output);
 272         if (ACPI_FAILURE(status)) {
 273                 printk(KERN_DEBUG
 274                        "%s: Run _GTF error: status = 0x%x\n",
 275                        __func__, status);
 276                 goto out;
 277         }
 278
 279         if (!output.length || !output.pointer) {
 280                 DEBPRINT("Run _GTF: "
 281                        "length or ptr is NULL (0x%llx, 0x%p)\n",
 282                        (unsigned long long)output.length,
 283                        output.pointer);
 284                 goto out;
 285         }
 286
 287         out_obj = output.pointer;
 288         if (out_obj->type != ACPI_TYPE_BUFFER) {
 289                 DEBPRINT("Run _GTF: error: "
 290                        "expected object type of ACPI_TYPE_BUFFER, "
 291                        "got 0x%x\n", out_obj->type);
 292                 err = -ENOENT;
 293                 kfree(output.pointer);
 294                 goto out;
 295         }
 296
 297         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 298             out_obj->buffer.length % REGS_PER_GTF) {
 299                 printk(KERN_ERR
 300                        "%s: unexpected GTF length (%d) or addr (0x%p)\n",
 301                        __func__, out_obj->buffer.length,
 302                        out_obj->buffer.pointer);
 303                 err = -ENOENT;
 304                 kfree(output.pointer);
 305                 goto out;
 306         }
 307
 308         *gtf_length = out_obj->buffer.length;
 309         *gtf_address = (unsigned long)out_obj->buffer.pointer;
 310         *obj_loc = (unsigned long)out_obj;
 311         DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
 312                  *gtf_length, *gtf_address, *obj_loc);
 313         err = 0;
 314 out:
 315         return err;
 316 }
 317
 318 /**
 319  * taskfile_load_raw - send taskfile registers to drive
 320  * @drive: drive to which output is sent
 321  * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
 322  *
 323  * Outputs IDE taskfile to the drive.
 324  */
 325 static int taskfile_load_raw(ide_drive_t *drive,
 326                               const struct taskfile_array *gtf)
 327 {
 328         ide_task_t args;
 329         int err = 0;
 330
 331         DEBPRINT("(0x1f1-1f7): hex: "
 332                "%02x %02x %02x %02x %02x %02x %02x\n",
 333                gtf->tfa[0], gtf->tfa[1], gtf->tfa[2],
 334                gtf->tfa[3], gtf->tfa[4], gtf->tfa[5], gtf->tfa[6]);
 335
 336         memset(&args, 0, sizeof(ide_task_t));
 337
 338         /* convert gtf to IDE Taskfile */
 339         memcpy(&args.tf_array[7], &gtf->tfa, 7);
 340         args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
 341
 342         if (!ide_acpigtf) {
 343                 DEBPRINT("_GTF execution disabled\n");
 344                 return err;
 345         }
 346
 347         err = ide_no_data_taskfile(drive, &args);
 348         if (err)
 349                 printk(KERN_ERR "%s: ide_no_data_taskfile failed: %u\n",
 350                        __func__, err);
 351
 352         return err;
 353 }
 354
 355 /**
 356  * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
 357  * @drive: the drive to which the taskfile command should be sent
 358  * @gtf_length: total number of bytes of _GTF taskfiles
 359  * @gtf_address: location of _GTF taskfile arrays
 360  *
 361  * Write {gtf_address, length gtf_length} in groups of
 362  * REGS_PER_GTF bytes.
 363  */
 364 static int do_drive_set_taskfiles(ide_drive_t *drive,
 365                                   unsigned int gtf_length,
 366                                   unsigned long gtf_address)
 367 {
 368         int                     rc = -ENODEV, err;
 369         int                     gtf_count = gtf_length / REGS_PER_GTF;
 370         int                     ix;
 371         struct taskfile_array   *gtf;
 372
 373         if (ide_noacpi)
 374                 return 0;
 375
 376         DEBPRINT("ENTER: %s, hard_port#: %d\n", drive->name, drive->dn);
 377
 378         if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
 379                 goto out;
 380
 381         if (!gtf_count)         /* shouldn't be here */
 382                 goto out;
 383
 384         DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
 385                  gtf_length, gtf_length, gtf_count, gtf_address);
 386
 387         if (gtf_length % REGS_PER_GTF) {
 388                 printk(KERN_ERR "%s: unexpected GTF length (%d)\n",
 389                        __func__, gtf_length);
 390                 goto out;
 391         }
 392
 393         rc = 0;
 394         for (ix = 0; ix < gtf_count; ix++) {
 395                 gtf = (struct taskfile_array *)
 396                         (gtf_address + ix * REGS_PER_GTF);
 397
 398                 /* send all TaskFile registers (0x1f1-0x1f7) *in*that*order* */
 399                 err = taskfile_load_raw(drive, gtf);
 400                 if (err)
 401                         rc = err;
 402         }
 403
 404 out:
 405         return rc;
 406 }
 407
 408 /**
 409  * ide_acpi_exec_tfs - get then write drive taskfile settings
 410  * @drive: the drive for which the taskfile settings should be
 411  *         written.
 412  *
 413  * According to the ACPI spec this should be called after _STM
 414  * has been evaluated for the interface. Some ACPI vendors interpret
 415  * that as a hard requirement and modify the taskfile according
 416  * to the Identify Drive information passed down with _STM.
 417  * So one should really make sure to call this only after _STM has
 418  * been executed.
 419  */
 420 int ide_acpi_exec_tfs(ide_drive_t *drive)
 421 {
 422         int             ret;
 423         unsigned int    gtf_length;
 424         unsigned long   gtf_address;
 425         unsigned long   obj_loc;
 426
 427         if (ide_noacpi)
 428                 return 0;
 429
 430         DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
 431
 432         ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
 433         if (ret < 0) {
 434                 DEBPRINT("get_GTF error (%d)\n", ret);
 435                 return ret;
 436         }
 437
 438         DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
 439
 440         ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
 441         kfree((void *)obj_loc);
 442         if (ret < 0) {
 443                 DEBPRINT("set_taskfiles error (%d)\n", ret);
 444         }
 445
 446         DEBPRINT("ret=%d\n", ret);
 447
 448         return ret;
 449 }
 450
 451 /**
 452  * ide_acpi_get_timing - get the channel (controller) timings
 453  * @hwif: target IDE interface (channel)
 454  *
 455  * This function executes the _GTM ACPI method for the target channel.
 456  *
 457  */
 458 void ide_acpi_get_timing(ide_hwif_t *hwif)
 459 {
 460         acpi_status             status;
 461         struct acpi_buffer      output;
 462         union acpi_object       *out_obj;
 463
 464         if (ide_noacpi)
 465                 return;
 466
 467         DEBPRINT("ENTER:\n");
 468
 469         if (!hwif->acpidata) {
 470                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 471                 return;
 472         }
 473
 474         /* Setting up output buffer for _GTM */
 475         output.length = ACPI_ALLOCATE_BUFFER;
 476         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
 477
 478         /* _GTM has no input parameters */
 479         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
 480                                       NULL, &output);
 481
 482         DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
 483                  status, output.pointer,
 484                  (unsigned long long)output.length);
 485
 486         if (ACPI_FAILURE(status)) {
 487                 DEBPRINT("Run _GTM error: status = 0x%x\n", status);
 488                 return;
 489         }
 490
 491         if (!output.length || !output.pointer) {
 492                 DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
 493                        (unsigned long long)output.length,
 494                        output.pointer);
 495                 kfree(output.pointer);
 496                 return;
 497         }
 498
 499         out_obj = output.pointer;
 500         if (out_obj->type != ACPI_TYPE_BUFFER) {
 501                 kfree(output.pointer);
 502                 DEBPRINT("Run _GTM: error: "
 503                        "expected object type of ACPI_TYPE_BUFFER, "
 504                        "got 0x%x\n", out_obj->type);
 505                 return;
 506         }
 507
 508         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
 509             out_obj->buffer.length != sizeof(struct GTM_buffer)) {
 510                 kfree(output.pointer);
 511                 printk(KERN_ERR
 512                         "%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
 513                         "addr (0x%p)\n",
 514                         __func__, out_obj->buffer.length,
 515                         sizeof(struct GTM_buffer), out_obj->buffer.pointer);
 516                 return;
 517         }
 518
 519         memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
 520                sizeof(struct GTM_buffer));
 521
 522         DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
 523                  out_obj->buffer.pointer, out_obj->buffer.length,
 524                  sizeof(struct GTM_buffer));
 525
 526         DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
 527                  hwif->acpidata->gtm.PIO_speed0,
 528                  hwif->acpidata->gtm.DMA_speed0,
 529                  hwif->acpidata->gtm.PIO_speed1,
 530                  hwif->acpidata->gtm.DMA_speed1,
 531                  hwif->acpidata->gtm.GTM_flags);
 532
 533         kfree(output.pointer);
 534 }
 535
 536 /**
 537  * ide_acpi_push_timing - set the channel (controller) timings
 538  * @hwif: target IDE interface (channel)
 539  *
 540  * This function executes the _STM ACPI method for the target channel.
 541  *
 542  * _STM requires Identify Drive data, which has to passed as an argument.
 543  * Unfortunately drive->id is a mangled version which we can't readily
 544  * use; hence we'll get the information afresh.
 545  */
 546 void ide_acpi_push_timing(ide_hwif_t *hwif)
 547 {
 548         acpi_status             status;
 549         struct acpi_object_list input;
 550         union acpi_object       in_params[3];
 551         struct ide_acpi_drive_link      *master = &hwif->acpidata->master;
 552         struct ide_acpi_drive_link      *slave = &hwif->acpidata->slave;
 553
 554         if (ide_noacpi)
 555                 return;
 556
 557         DEBPRINT("ENTER:\n");
 558
 559         if (!hwif->acpidata) {
 560                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 561                 return;
 562         }
 563
 564         /* Give the GTM buffer + drive Identify data to the channel via the
 565          * _STM method: */
 566         /* setup input parameters buffer for _STM */
 567         input.count = 3;
 568         input.pointer = in_params;
 569         in_params[0].type = ACPI_TYPE_BUFFER;
 570         in_params[0].buffer.length = sizeof(struct GTM_buffer);
 571         in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
 572         in_params[1].type = ACPI_TYPE_BUFFER;
 573         in_params[1].buffer.length = ATA_ID_WORDS * 2;
 574         in_params[1].buffer.pointer = (u8 *)&master->idbuff;
 575         in_params[2].type = ACPI_TYPE_BUFFER;
 576         in_params[2].buffer.length = ATA_ID_WORDS * 2;
 577         in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
 578         /* Output buffer: _STM has no output */
 579
 580         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
 581                                       &input, NULL);
 582
 583         if (ACPI_FAILURE(status)) {
 584                 DEBPRINT("Run _STM error: status = 0x%x\n", status);
 585         }
 586         DEBPRINT("_STM status: %d\n", status);
 587 }
 588
 589 /**
 590  * ide_acpi_set_state - set the channel power state
 591  * @hwif: target IDE interface
 592  * @on: state, on/off
 593  *
 594  * This function executes the _PS0/_PS3 ACPI method to set the power state.
 595  * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
 596  */
 597 void ide_acpi_set_state(ide_hwif_t *hwif, int on)
 598 {
 599         ide_drive_t *drive;
 600         int i;
 601
 602         if (ide_noacpi || ide_noacpi_psx)
 603                 return;
 604
 605         DEBPRINT("ENTER:\n");
 606
 607         if (!hwif->acpidata) {
 608                 DEBPRINT("no ACPI data for %s\n", hwif->name);
 609                 return;
 610         }
 611
 612         /* channel first and then drives for power on and verse versa for power off */
 613         if (on)
 614                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
 615
 616         ide_port_for_each_present_dev(i, drive, hwif) {
 617                 if (drive->acpidata->obj_handle)
 618                         acpi_bus_set_power(drive->acpidata->obj_handle,
 619                                            on ? ACPI_STATE_D0 : ACPI_STATE_D3);
 620         }
 621
 622         if (!on)
 623                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D3);
 624 }
 625
 626 /**
 627  * ide_acpi_init - initialize the ACPI link for an IDE interface
 628  * @hwif: target IDE interface (channel)
 629  *
 630  * The ACPI spec is not quite clear when the drive identify buffer
 631  * should be obtained. Calling IDENTIFY DEVICE during shutdown
 632  * is not the best of ideas as the drive might already being put to
 633  * sleep. And obviously we can't call it during resume.
 634  * So we get the information during startup; but this means that
 635  * any changes during run-time will be lost after resume.
 636  */
 637 void ide_acpi_init(ide_hwif_t *hwif)
 638 {
 639         ide_acpi_blacklist();
 640
 641         hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
 642         if (!hwif->acpidata)
 643                 return;
 644
 645         hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
 646         if (!hwif->acpidata->obj_handle) {
 647                 DEBPRINT("no ACPI object for %s found\n", hwif->name);
 648                 kfree(hwif->acpidata);
 649                 hwif->acpidata = NULL;
 650         }
 651 }
 652
 653 void ide_acpi_port_init_devices(ide_hwif_t *hwif)
 654 {
 655         ide_drive_t *drive;
 656         int i, err;
 657
 658         if (hwif->acpidata == NULL)
 659                 return;
 660
 661         /*
 662          * The ACPI spec mandates that we send information
 663          * for both drives, regardless whether they are connected
 664          * or not.
 665          */
 666         hwif->devices[0]->acpidata = &hwif->acpidata->master;
 667         hwif->devices[1]->acpidata = &hwif->acpidata->slave;
 668
 669         /* get _ADR info for each device */
 670         ide_port_for_each_present_dev(i, drive, hwif) {
 671                 acpi_handle dev_handle;
 672
 673                 DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
 674                          drive->name, hwif->channel, drive->dn & 1);
 675
 676                 /* TBD: could also check ACPI object VALID bits */
 677                 dev_handle = acpi_get_child(hwif->acpidata->obj_handle,
 678                                             drive->dn & 1);
 679
 680                 DEBPRINT("drive %s handle 0x%p\n", drive->name, dev_handle);
 681
 682                 drive->acpidata->obj_handle = dev_handle;
 683         }
 684
 685         /* send IDENTIFY for each device */
 686         ide_port_for_each_present_dev(i, drive, hwif) {
 687                 err = taskfile_lib_get_identify(drive, drive->acpidata->idbuff);
 688                 if (err)
 689                         DEBPRINT("identify device %s failed (%d)\n",
 690                                  drive->name, err);
 691         }
 692
 693         if (!ide_acpionboot) {
 694                 DEBPRINT("ACPI methods disabled on boot\n");
 695                 return;
 696         }
 697
 698         /* ACPI _PS0 before _STM */
 699         ide_acpi_set_state(hwif, 1);
 700         /*
 701          * ACPI requires us to call _STM on startup
 702          */
 703         ide_acpi_get_timing(hwif);
 704         ide_acpi_push_timing(hwif);
 705
 706         ide_port_for_each_present_dev(i, drive, hwif) {
 707                 ide_acpi_exec_tfs(drive);
 708         }
 709 }