linux/drivers/acpi/pci_root.c
<<
>>
Prefs
   1/*
   2 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
   3 *
   4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6 *
   7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8 *
   9 *  This program is free software; you can redistribute it and/or modify
  10 *  it under the terms of the GNU General Public License as published by
  11 *  the Free Software Foundation; either version 2 of the License, or (at
  12 *  your option) any later version.
  13 *
  14 *  This program is distributed in the hope that it will be useful, but
  15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17 *  General Public License for more details.
  18 *
  19 *  You should have received a copy of the GNU General Public License along
  20 *  with this program; if not, write to the Free Software Foundation, Inc.,
  21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22 *
  23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24 */
  25
  26#include <linux/kernel.h>
  27#include <linux/module.h>
  28#include <linux/init.h>
  29#include <linux/types.h>
  30#include <linux/spinlock.h>
  31#include <linux/pm.h>
  32#include <linux/pm_runtime.h>
  33#include <linux/pci.h>
  34#include <linux/pci-acpi.h>
  35#include <linux/pci-aspm.h>
  36#include <linux/acpi.h>
  37#include <linux/slab.h>
  38#include <acpi/acpi_bus.h>
  39#include <acpi/acpi_drivers.h>
  40#include <acpi/apei.h>
  41
  42#define PREFIX "ACPI: "
  43
  44#define _COMPONENT              ACPI_PCI_COMPONENT
  45ACPI_MODULE_NAME("pci_root");
  46#define ACPI_PCI_ROOT_CLASS             "pci_bridge"
  47#define ACPI_PCI_ROOT_DEVICE_NAME       "PCI Root Bridge"
  48static int acpi_pci_root_add(struct acpi_device *device);
  49static int acpi_pci_root_remove(struct acpi_device *device, int type);
  50static int acpi_pci_root_start(struct acpi_device *device);
  51
  52#define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
  53                                | OSC_ACTIVE_STATE_PWR_SUPPORT \
  54                                | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
  55                                | OSC_MSI_SUPPORT)
  56
  57static const struct acpi_device_id root_device_ids[] = {
  58        {"PNP0A03", 0},
  59        {"", 0},
  60};
  61MODULE_DEVICE_TABLE(acpi, root_device_ids);
  62
  63static struct acpi_driver acpi_pci_root_driver = {
  64        .name = "pci_root",
  65        .class = ACPI_PCI_ROOT_CLASS,
  66        .ids = root_device_ids,
  67        .ops = {
  68                .add = acpi_pci_root_add,
  69                .remove = acpi_pci_root_remove,
  70                .start = acpi_pci_root_start,
  71                },
  72};
  73
  74static LIST_HEAD(acpi_pci_roots);
  75
  76static struct acpi_pci_driver *sub_driver;
  77static DEFINE_MUTEX(osc_lock);
  78
  79int acpi_pci_register_driver(struct acpi_pci_driver *driver)
  80{
  81        int n = 0;
  82        struct acpi_pci_root *root;
  83
  84        struct acpi_pci_driver **pptr = &sub_driver;
  85        while (*pptr)
  86                pptr = &(*pptr)->next;
  87        *pptr = driver;
  88
  89        if (!driver->add)
  90                return 0;
  91
  92        list_for_each_entry(root, &acpi_pci_roots, node) {
  93                driver->add(root->device->handle);
  94                n++;
  95        }
  96
  97        return n;
  98}
  99
 100EXPORT_SYMBOL(acpi_pci_register_driver);
 101
 102void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
 103{
 104        struct acpi_pci_root *root;
 105
 106        struct acpi_pci_driver **pptr = &sub_driver;
 107        while (*pptr) {
 108                if (*pptr == driver)
 109                        break;
 110                pptr = &(*pptr)->next;
 111        }
 112        BUG_ON(!*pptr);
 113        *pptr = (*pptr)->next;
 114
 115        if (!driver->remove)
 116                return;
 117
 118        list_for_each_entry(root, &acpi_pci_roots, node)
 119                driver->remove(root->device->handle);
 120}
 121
 122EXPORT_SYMBOL(acpi_pci_unregister_driver);
 123
 124acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
 125{
 126        struct acpi_pci_root *root;
 127        
 128        list_for_each_entry(root, &acpi_pci_roots, node)
 129                if ((root->segment == (u16) seg) &&
 130                    (root->secondary.start == (u16) bus))
 131                        return root->device->handle;
 132        return NULL;            
 133}
 134
 135EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
 136
 137/**
 138 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
 139 * @handle - the ACPI CA node in question.
 140 *
 141 * Note: we could make this API take a struct acpi_device * instead, but
 142 * for now, it's more convenient to operate on an acpi_handle.
 143 */
 144int acpi_is_root_bridge(acpi_handle handle)
 145{
 146        int ret;
 147        struct acpi_device *device;
 148
 149        ret = acpi_bus_get_device(handle, &device);
 150        if (ret)
 151                return 0;
 152
 153        ret = acpi_match_device_ids(device, root_device_ids);
 154        if (ret)
 155                return 0;
 156        else
 157                return 1;
 158}
 159EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
 160
 161static acpi_status
 162get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
 163{
 164        struct resource *res = data;
 165        struct acpi_resource_address64 address;
 166
 167        if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
 168            resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
 169            resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
 170                return AE_OK;
 171
 172        acpi_resource_to_address64(resource, &address);
 173        if ((address.address_length > 0) &&
 174            (address.resource_type == ACPI_BUS_NUMBER_RANGE)) {
 175                res->start = address.minimum;
 176                res->end = address.minimum + address.address_length - 1;
 177        }
 178
 179        return AE_OK;
 180}
 181
 182static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
 183                                             struct resource *res)
 184{
 185        acpi_status status;
 186
 187        res->start = -1;
 188        status =
 189            acpi_walk_resources(handle, METHOD_NAME__CRS,
 190                                get_root_bridge_busnr_callback, res);
 191        if (ACPI_FAILURE(status))
 192                return status;
 193        if (res->start == -1)
 194                return AE_ERROR;
 195        return AE_OK;
 196}
 197
 198static void acpi_pci_bridge_scan(struct acpi_device *device)
 199{
 200        int status;
 201        struct acpi_device *child = NULL;
 202
 203        if (device->flags.bus_address)
 204                if (device->parent && device->parent->ops.bind) {
 205                        status = device->parent->ops.bind(device);
 206                        if (!status) {
 207                                list_for_each_entry(child, &device->children, node)
 208                                        acpi_pci_bridge_scan(child);
 209                        }
 210                }
 211}
 212
 213static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766";
 214
 215static acpi_status acpi_pci_run_osc(acpi_handle handle,
 216                                    const u32 *capbuf, u32 *retval)
 217{
 218        struct acpi_osc_context context = {
 219                .uuid_str = pci_osc_uuid_str,
 220                .rev = 1,
 221                .cap.length = 12,
 222                .cap.pointer = (void *)capbuf,
 223        };
 224        acpi_status status;
 225
 226        status = acpi_run_osc(handle, &context);
 227        if (ACPI_SUCCESS(status)) {
 228                *retval = *((u32 *)(context.ret.pointer + 8));
 229                kfree(context.ret.pointer);
 230        }
 231        return status;
 232}
 233
 234static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
 235                                        u32 support,
 236                                        u32 *control)
 237{
 238        acpi_status status;
 239        u32 result, capbuf[3];
 240
 241        support &= OSC_PCI_SUPPORT_MASKS;
 242        support |= root->osc_support_set;
 243
 244        capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
 245        capbuf[OSC_SUPPORT_TYPE] = support;
 246        if (control) {
 247                *control &= OSC_PCI_CONTROL_MASKS;
 248                capbuf[OSC_CONTROL_TYPE] = *control | root->osc_control_set;
 249        } else {
 250                /* Run _OSC query for all possible controls. */
 251                capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS;
 252        }
 253
 254        status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
 255        if (ACPI_SUCCESS(status)) {
 256                root->osc_support_set = support;
 257                if (control)
 258                        *control = result;
 259        }
 260        return status;
 261}
 262
 263static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
 264{
 265        acpi_status status;
 266        acpi_handle tmp;
 267
 268        status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
 269        if (ACPI_FAILURE(status))
 270                return status;
 271        mutex_lock(&osc_lock);
 272        status = acpi_pci_query_osc(root, flags, NULL);
 273        mutex_unlock(&osc_lock);
 274        return status;
 275}
 276
 277struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
 278{
 279        struct acpi_pci_root *root;
 280
 281        list_for_each_entry(root, &acpi_pci_roots, node) {
 282                if (root->device->handle == handle)
 283                        return root;
 284        }
 285        return NULL;
 286}
 287EXPORT_SYMBOL_GPL(acpi_pci_find_root);
 288
 289struct acpi_handle_node {
 290        struct list_head node;
 291        acpi_handle handle;
 292};
 293
 294/**
 295 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
 296 * @handle: the handle in question
 297 *
 298 * Given an ACPI CA handle, the desired PCI device is located in the
 299 * list of PCI devices.
 300 *
 301 * If the device is found, its reference count is increased and this
 302 * function returns a pointer to its data structure.  The caller must
 303 * decrement the reference count by calling pci_dev_put().
 304 * If no device is found, %NULL is returned.
 305 */
 306struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 307{
 308        int dev, fn;
 309        unsigned long long adr;
 310        acpi_status status;
 311        acpi_handle phandle;
 312        struct pci_bus *pbus;
 313        struct pci_dev *pdev = NULL;
 314        struct acpi_handle_node *node, *tmp;
 315        struct acpi_pci_root *root;
 316        LIST_HEAD(device_list);
 317
 318        /*
 319         * Walk up the ACPI CA namespace until we reach a PCI root bridge.
 320         */
 321        phandle = handle;
 322        while (!acpi_is_root_bridge(phandle)) {
 323                node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
 324                if (!node)
 325                        goto out;
 326
 327                INIT_LIST_HEAD(&node->node);
 328                node->handle = phandle;
 329                list_add(&node->node, &device_list);
 330
 331                status = acpi_get_parent(phandle, &phandle);
 332                if (ACPI_FAILURE(status))
 333                        goto out;
 334        }
 335
 336        root = acpi_pci_find_root(phandle);
 337        if (!root)
 338                goto out;
 339
 340        pbus = root->bus;
 341
 342        /*
 343         * Now, walk back down the PCI device tree until we return to our
 344         * original handle. Assumes that everything between the PCI root
 345         * bridge and the device we're looking for must be a P2P bridge.
 346         */
 347        list_for_each_entry(node, &device_list, node) {
 348                acpi_handle hnd = node->handle;
 349                status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
 350                if (ACPI_FAILURE(status))
 351                        goto out;
 352                dev = (adr >> 16) & 0xffff;
 353                fn  = adr & 0xffff;
 354
 355                pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
 356                if (!pdev || hnd == handle)
 357                        break;
 358
 359                pbus = pdev->subordinate;
 360                pci_dev_put(pdev);
 361
 362                /*
 363                 * This function may be called for a non-PCI device that has a
 364                 * PCI parent (eg. a disk under a PCI SATA controller).  In that
 365                 * case pdev->subordinate will be NULL for the parent.
 366                 */
 367                if (!pbus) {
 368                        dev_dbg(&pdev->dev, "Not a PCI-to-PCI bridge\n");
 369                        pdev = NULL;
 370                        break;
 371                }
 372        }
 373out:
 374        list_for_each_entry_safe(node, tmp, &device_list, node)
 375                kfree(node);
 376
 377        return pdev;
 378}
 379EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 380
 381/**
 382 * acpi_pci_osc_control_set - Request control of PCI root _OSC features.
 383 * @handle: ACPI handle of a PCI root bridge (or PCIe Root Complex).
 384 * @mask: Mask of _OSC bits to request control of, place to store control mask.
 385 * @req: Mask of _OSC bits the control of is essential to the caller.
 386 *
 387 * Run _OSC query for @mask and if that is successful, compare the returned
 388 * mask of control bits with @req.  If all of the @req bits are set in the
 389 * returned mask, run _OSC request for it.
 390 *
 391 * The variable at the @mask address may be modified regardless of whether or
 392 * not the function returns success.  On success it will contain the mask of
 393 * _OSC bits the BIOS has granted control of, but its contents are meaningless
 394 * on failure.
 395 **/
 396acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
 397{
 398        struct acpi_pci_root *root;
 399        acpi_status status;
 400        u32 ctrl, capbuf[3];
 401        acpi_handle tmp;
 402
 403        if (!mask)
 404                return AE_BAD_PARAMETER;
 405
 406        ctrl = *mask & OSC_PCI_CONTROL_MASKS;
 407        if ((ctrl & req) != req)
 408                return AE_TYPE;
 409
 410        root = acpi_pci_find_root(handle);
 411        if (!root)
 412                return AE_NOT_EXIST;
 413
 414        status = acpi_get_handle(handle, "_OSC", &tmp);
 415        if (ACPI_FAILURE(status))
 416                return status;
 417
 418        mutex_lock(&osc_lock);
 419
 420        *mask = ctrl | root->osc_control_set;
 421        /* No need to evaluate _OSC if the control was already granted. */
 422        if ((root->osc_control_set & ctrl) == ctrl)
 423                goto out;
 424
 425        /* Need to check the available controls bits before requesting them. */
 426        while (*mask) {
 427                status = acpi_pci_query_osc(root, root->osc_support_set, mask);
 428                if (ACPI_FAILURE(status))
 429                        goto out;
 430                if (ctrl == *mask)
 431                        break;
 432                ctrl = *mask;
 433        }
 434
 435        if ((ctrl & req) != req) {
 436                status = AE_SUPPORT;
 437                goto out;
 438        }
 439
 440        capbuf[OSC_QUERY_TYPE] = 0;
 441        capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
 442        capbuf[OSC_CONTROL_TYPE] = ctrl;
 443        status = acpi_pci_run_osc(handle, capbuf, mask);
 444        if (ACPI_SUCCESS(status))
 445                root->osc_control_set = *mask;
 446out:
 447        mutex_unlock(&osc_lock);
 448        return status;
 449}
 450EXPORT_SYMBOL(acpi_pci_osc_control_set);
 451
 452static int __devinit acpi_pci_root_add(struct acpi_device *device)
 453{
 454        unsigned long long segment, bus;
 455        acpi_status status;
 456        int result;
 457        struct acpi_pci_root *root;
 458        acpi_handle handle;
 459        struct acpi_device *child;
 460        u32 flags, base_flags;
 461
 462        root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
 463        if (!root)
 464                return -ENOMEM;
 465
 466        segment = 0;
 467        status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
 468                                       &segment);
 469        if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 470                printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
 471                result = -ENODEV;
 472                goto end;
 473        }
 474
 475        /* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
 476        root->secondary.flags = IORESOURCE_BUS;
 477        status = try_get_root_bridge_busnr(device->handle, &root->secondary);
 478        if (ACPI_FAILURE(status)) {
 479                /*
 480                 * We need both the start and end of the downstream bus range
 481                 * to interpret _CBA (MMCONFIG base address), so it really is
 482                 * supposed to be in _CRS.  If we don't find it there, all we
 483                 * can do is assume [_BBN-0xFF] or [0-0xFF].
 484                 */
 485                root->secondary.end = 0xFF;
 486                printk(KERN_WARNING FW_BUG PREFIX
 487                       "no secondary bus range in _CRS\n");
 488                status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,
 489                                               NULL, &bus);
 490                if (ACPI_SUCCESS(status))
 491                        root->secondary.start = bus;
 492                else if (status == AE_NOT_FOUND)
 493                        root->secondary.start = 0;
 494                else {
 495                        printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
 496                        result = -ENODEV;
 497                        goto end;
 498                }
 499        }
 500
 501        INIT_LIST_HEAD(&root->node);
 502        root->device = device;
 503        root->segment = segment & 0xFFFF;
 504        strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 505        strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 506        device->driver_data = root;
 507
 508        root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
 509
 510        /*
 511         * All supported architectures that use ACPI have support for
 512         * PCI domains, so we indicate this in _OSC support capabilities.
 513         */
 514        flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
 515        acpi_pci_osc_support(root, flags);
 516
 517        /*
 518         * TBD: Need PCI interface for enumeration/configuration of roots.
 519         */
 520
 521        /* TBD: Locking */
 522        list_add_tail(&root->node, &acpi_pci_roots);
 523
 524        printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
 525               acpi_device_name(device), acpi_device_bid(device),
 526               root->segment, &root->secondary);
 527
 528        /*
 529         * Scan the Root Bridge
 530         * --------------------
 531         * Must do this prior to any attempt to bind the root device, as the
 532         * PCI namespace does not get created until this call is made (and 
 533         * thus the root bridge's pci_dev does not exist).
 534         */
 535        root->bus = pci_acpi_scan_root(root);
 536        if (!root->bus) {
 537                printk(KERN_ERR PREFIX
 538                            "Bus %04x:%02x not present in PCI namespace\n",
 539                            root->segment, (unsigned int)root->secondary.start);
 540                result = -ENODEV;
 541                goto end;
 542        }
 543
 544        /*
 545         * Attach ACPI-PCI Context
 546         * -----------------------
 547         * Thus binding the ACPI and PCI devices.
 548         */
 549        result = acpi_pci_bind_root(device);
 550        if (result)
 551                goto end;
 552
 553        /*
 554         * PCI Routing Table
 555         * -----------------
 556         * Evaluate and parse _PRT, if exists.
 557         */
 558        status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
 559        if (ACPI_SUCCESS(status))
 560                result = acpi_pci_irq_add_prt(device->handle, root->bus);
 561
 562        /*
 563         * Scan and bind all _ADR-Based Devices
 564         */
 565        list_for_each_entry(child, &device->children, node)
 566                acpi_pci_bridge_scan(child);
 567
 568        /* Indicate support for various _OSC capabilities. */
 569        if (pci_ext_cfg_avail(root->bus->self))
 570                flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
 571        if (pcie_aspm_support_enabled())
 572                flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
 573                        OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
 574        if (pci_msi_enabled())
 575                flags |= OSC_MSI_SUPPORT;
 576        if (flags != base_flags) {
 577                status = acpi_pci_osc_support(root, flags);
 578                if (ACPI_FAILURE(status)) {
 579                        dev_info(root->bus->bridge, "ACPI _OSC support "
 580                                "notification failed, disabling PCIe ASPM\n");
 581                        pcie_no_aspm();
 582                        flags = base_flags;
 583                }
 584        }
 585
 586        if (!pcie_ports_disabled
 587            && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
 588                flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
 589                        | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
 590                        | OSC_PCI_EXPRESS_PME_CONTROL;
 591
 592                if (pci_aer_available()) {
 593                        if (aer_acpi_firmware_first())
 594                                dev_dbg(root->bus->bridge,
 595                                        "PCIe errors handled by BIOS.\n");
 596                        else
 597                                flags |= OSC_PCI_EXPRESS_AER_CONTROL;
 598                }
 599
 600                dev_info(root->bus->bridge,
 601                        "Requesting ACPI _OSC control (0x%02x)\n", flags);
 602
 603                status = acpi_pci_osc_control_set(device->handle, &flags,
 604                                        OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
 605                if (ACPI_SUCCESS(status)) {
 606                        dev_info(root->bus->bridge,
 607                                "ACPI _OSC control (0x%02x) granted\n", flags);
 608                        if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
 609                                /*
 610                                 * We have ASPM control, but the FADT indicates
 611                                 * that it's unsupported. Clear it.
 612                                 */
 613                                pcie_clear_aspm(root->bus);
 614                        }
 615                } else {
 616                        dev_info(root->bus->bridge,
 617                                "ACPI _OSC request failed (%s), "
 618                                "returned control mask: 0x%02x\n",
 619                                acpi_format_exception(status), flags);
 620                        pr_info("ACPI _OSC control for PCIe not granted, "
 621                                "disabling ASPM\n");
 622                        pcie_no_aspm();
 623                }
 624        } else {
 625                dev_info(root->bus->bridge,
 626                         "Unable to request _OSC control "
 627                         "(_OSC support mask: 0x%02x)\n", flags);
 628        }
 629
 630        pci_acpi_add_bus_pm_notifier(device, root->bus);
 631        if (device->wakeup.flags.run_wake)
 632                device_set_run_wake(root->bus->bridge, true);
 633
 634        return 0;
 635
 636end:
 637        if (!list_empty(&root->node))
 638                list_del(&root->node);
 639        kfree(root);
 640        return result;
 641}
 642
 643static int acpi_pci_root_start(struct acpi_device *device)
 644{
 645        struct acpi_pci_root *root = acpi_driver_data(device);
 646
 647        pci_bus_add_devices(root->bus);
 648        return 0;
 649}
 650
 651static int acpi_pci_root_remove(struct acpi_device *device, int type)
 652{
 653        struct acpi_pci_root *root = acpi_driver_data(device);
 654
 655        device_set_run_wake(root->bus->bridge, false);
 656        pci_acpi_remove_bus_pm_notifier(device);
 657
 658        kfree(root);
 659        return 0;
 660}
 661
 662static int __init acpi_pci_root_init(void)
 663{
 664        acpi_hest_init();
 665
 666        if (acpi_pci_disabled)
 667                return 0;
 668
 669        pci_acpi_crs_quirks();
 670        if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
 671                return -ENODEV;
 672
 673        return 0;
 674}
 675
 676subsys_initcall(acpi_pci_root_init);
 677
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.