drivers/pci/hotplug/acpiphp_glue.c

   1 /*
   2  * ACPI PCI HotPlug glue functions to ACPI CA subsystem
   3  *
   4  * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
   5  * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
   6  * Copyright (C) 2002,2003 NEC Corporation
   7  * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
   8  * Copyright (C) 2003-2005 Hewlett Packard
   9  * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
  10  * Copyright (C) 2005 Intel Corporation
  11  *
  12  * All rights reserved.
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or (at
  17  * your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  22  * NON INFRINGEMENT.  See the GNU General Public License for more
  23  * details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  28  *
  29  * Send feedback to <kristen.c.accardi@intel.com>
  30  *
  31  */
  32
  33 /*
  34  * Lifetime rules for pci_dev:
  35  *  - The one in acpiphp_bridge has its refcount elevated by pci_get_slot()
  36  *    when the bridge is scanned and it loses a refcount when the bridge
  37  *    is removed.
  38  *  - When a P2P bridge is present, we elevate the refcount on the subordinate
  39  *    bus. It loses the refcount when the the driver unloads.
  40  */
  41
  42 #define pr_fmt(fmt) "acpiphp_glue: " fmt
  43
  44 #include <linux/init.h>
  45 #include <linux/module.h>
  46
  47 #include <linux/kernel.h>
  48 #include <linux/pci.h>
  49 #include <linux/pci_hotplug.h>
  50 #include <linux/pci-acpi.h>
  51 #include <linux/pm_runtime.h>
  52 #include <linux/mutex.h>
  53 #include <linux/slab.h>
  54 #include <linux/acpi.h>
  55
  56 #include "../pci.h"
  57 #include "acpiphp.h"
  58
  59 static LIST_HEAD(bridge_list);
  60 static DEFINE_MUTEX(bridge_mutex);
  61 static DEFINE_MUTEX(acpiphp_context_lock);
  62
  63 static void handle_hotplug_event(acpi_handle handle, u32 type, void *data);
  64 static void acpiphp_sanitize_bus(struct pci_bus *bus);
  65 static void acpiphp_set_hpp_values(struct pci_bus *bus);
  66 static void hotplug_event(acpi_handle handle, u32 type, void *data);
  67 static void free_bridge(struct kref *kref);
  68
  69 static void acpiphp_context_handler(acpi_handle handle, void *context)
  70 {
  71         /* Intentionally empty. */
  72 }
  73
  74 /**
  75  * acpiphp_init_context - Create hotplug context and grab a reference to it.
  76  * @handle: ACPI object handle to create the context for.
  77  *
  78  * Call under acpiphp_context_lock.
  79  */
  80 static struct acpiphp_context *acpiphp_init_context(acpi_handle handle)
  81 {
  82         struct acpiphp_context *context;
  83         acpi_status status;
  84
  85         context = kzalloc(sizeof(*context), GFP_KERNEL);
  86         if (!context)
  87                 return NULL;
  88
  89         context->handle = handle;
  90         context->refcount = 1;
  91         status = acpi_attach_data(handle, acpiphp_context_handler, context);
  92         if (ACPI_FAILURE(status)) {
  93                 kfree(context);
  94                 return NULL;
  95         }
  96         return context;
  97 }
  98
  99 /**
 100  * acpiphp_get_context - Get hotplug context and grab a reference to it.
 101  * @handle: ACPI object handle to get the context for.
 102  *
 103  * Call under acpiphp_context_lock.
 104  */
 105 static struct acpiphp_context *acpiphp_get_context(acpi_handle handle)
 106 {
 107         struct acpiphp_context *context = NULL;
 108         acpi_status status;
 109         void *data;
 110
 111         status = acpi_get_data(handle, acpiphp_context_handler, &data);
 112         if (ACPI_SUCCESS(status)) {
 113                 context = data;
 114                 context->refcount++;
 115         }
 116         return context;
 117 }
 118
 119 /**
 120  * acpiphp_put_context - Drop a reference to ACPI hotplug context.
 121  * @handle: ACPI object handle to put the context for.
 122  *
 123  * The context object is removed if there are no more references to it.
 124  *
 125  * Call under acpiphp_context_lock.
 126  */
 127 static void acpiphp_put_context(struct acpiphp_context *context)
 128 {
 129         if (--context->refcount)
 130                 return;
 131
 132         WARN_ON(context->bridge);
 133         acpi_detach_data(context->handle, acpiphp_context_handler);
 134         kfree(context);
 135 }
 136
 137 static inline void get_bridge(struct acpiphp_bridge *bridge)
 138 {
 139         kref_get(&bridge->ref);
 140 }
 141
 142 static inline void put_bridge(struct acpiphp_bridge *bridge)
 143 {
 144         kref_put(&bridge->ref, free_bridge);
 145 }
 146
 147 static void free_bridge(struct kref *kref)
 148 {
 149         struct acpiphp_context *context;
 150         struct acpiphp_bridge *bridge;
 151         struct acpiphp_slot *slot, *next;
 152         struct acpiphp_func *func, *tmp;
 153
 154         mutex_lock(&acpiphp_context_lock);
 155
 156         bridge = container_of(kref, struct acpiphp_bridge, ref);
 157
 158         list_for_each_entry_safe(slot, next, &bridge->slots, node) {
 159                 list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
 160                         acpiphp_put_context(func_to_context(func));
 161
 162                 kfree(slot);
 163         }
 164
 165         context = bridge->context;
 166         /* Root bridges will not have hotplug context. */
 167         if (context) {
 168                 /* Release the reference taken by acpiphp_enumerate_slots(). */
 169                 put_bridge(context->func.parent);
 170                 context->bridge = NULL;
 171                 acpiphp_put_context(context);
 172         }
 173
 174         put_device(&bridge->pci_bus->dev);
 175         pci_dev_put(bridge->pci_dev);
 176         kfree(bridge);
 177
 178         mutex_unlock(&acpiphp_context_lock);
 179 }
 180
 181 /*
 182  * the _DCK method can do funny things... and sometimes not
 183  * hah-hah funny.
 184  *
 185  * TBD - figure out a way to only call fixups for
 186  * systems that require them.
 187  */
 188 static void post_dock_fixups(acpi_handle not_used, u32 event, void *data)
 189 {
 190         struct acpiphp_context *context = data;
 191         struct pci_bus *bus = context->func.slot->bus;
 192         u32 buses;
 193
 194         if (!bus->self)
 195                 return;
 196
 197         /* fixup bad _DCK function that rewrites
 198          * secondary bridge on slot
 199          */
 200         pci_read_config_dword(bus->self,
 201                         PCI_PRIMARY_BUS,
 202                         &buses);
 203
 204         if (((buses >> 8) & 0xff) != bus->busn_res.start) {
 205                 buses = (buses & 0xff000000)
 206                         | ((unsigned int)(bus->primary)     <<  0)
 207                         | ((unsigned int)(bus->busn_res.start)   <<  8)
 208                         | ((unsigned int)(bus->busn_res.end) << 16);
 209                 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
 210         }
 211 }
 212
 213
 214 static const struct acpi_dock_ops acpiphp_dock_ops = {
 215         .fixup = post_dock_fixups,
 216         .handler = hotplug_event,
 217 };
 218
 219 /* Check whether the PCI device is managed by native PCIe hotplug driver */
 220 static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
 221 {
 222         u32 reg32;
 223         acpi_handle tmp;
 224         struct acpi_pci_root *root;
 225
 226         /* Check whether the PCIe port supports native PCIe hotplug */
 227         if (pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32))
 228                 return false;
 229         if (!(reg32 & PCI_EXP_SLTCAP_HPC))
 230                 return false;
 231
 232         /*
 233          * Check whether native PCIe hotplug has been enabled for
 234          * this PCIe hierarchy.
 235          */
 236         tmp = acpi_find_root_bridge_handle(pdev);
 237         if (!tmp)
 238                 return false;
 239         root = acpi_pci_find_root(tmp);
 240         if (!root)
 241                 return false;
 242         if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
 243                 return false;
 244
 245         return true;
 246 }
 247
 248 static void acpiphp_dock_init(void *data)
 249 {
 250         struct acpiphp_context *context = data;
 251
 252         get_bridge(context->func.parent);
 253 }
 254
 255 static void acpiphp_dock_release(void *data)
 256 {
 257         struct acpiphp_context *context = data;
 258
 259         put_bridge(context->func.parent);
 260 }
 261
 262 /* callback routine to register each ACPI PCI slot object */
 263 static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
 264                                  void **rv)
 265 {
 266         struct acpiphp_bridge *bridge = data;
 267         struct acpiphp_context *context;
 268         struct acpiphp_slot *slot;
 269         struct acpiphp_func *newfunc;
 270         acpi_status status = AE_OK;
 271         unsigned long long adr;
 272         int device, function;
 273         struct pci_bus *pbus = bridge->pci_bus;
 274         struct pci_dev *pdev = bridge->pci_dev;
 275         u32 val;
 276
 277         if (pdev && device_is_managed_by_native_pciehp(pdev))
 278                 return AE_OK;
 279
 280         status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
 281         if (ACPI_FAILURE(status)) {
 282                 if (status != AE_NOT_FOUND)
 283                         acpi_handle_warn(handle,
 284                                 "can't evaluate _ADR (%#x)\n", status);
 285                 return AE_OK;
 286         }
 287
 288         device = (adr >> 16) & 0xffff;
 289         function = adr & 0xffff;
 290
 291         mutex_lock(&acpiphp_context_lock);
 292         context = acpiphp_init_context(handle);
 293         if (!context) {
 294                 mutex_unlock(&acpiphp_context_lock);
 295                 acpi_handle_err(handle, "No hotplug context\n");
 296                 return AE_NOT_EXIST;
 297         }
 298         newfunc = &context->func;
 299         newfunc->function = function;
 300         newfunc->parent = bridge;
 301         mutex_unlock(&acpiphp_context_lock);
 302
 303         if (acpi_has_method(handle, "_EJ0"))
 304                 newfunc->flags = FUNC_HAS_EJ0;
 305
 306         if (acpi_has_method(handle, "_STA"))
 307                 newfunc->flags |= FUNC_HAS_STA;
 308
 309         if (acpi_has_method(handle, "_DCK"))
 310                 newfunc->flags |= FUNC_HAS_DCK;
 311
 312         /* search for objects that share the same slot */
 313         list_for_each_entry(slot, &bridge->slots, node)
 314                 if (slot->device == device)
 315                         goto slot_found;
 316
 317         slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
 318         if (!slot) {
 319                 status = AE_NO_MEMORY;
 320                 goto err;
 321         }
 322
 323         slot->bus = bridge->pci_bus;
 324         slot->device = device;
 325         INIT_LIST_HEAD(&slot->funcs);
 326         mutex_init(&slot->crit_sect);
 327
 328         list_add_tail(&slot->node, &bridge->slots);
 329
 330         /* Register slots for ejectable functions only. */
 331         if (acpi_pci_check_ejectable(pbus, handle)  || is_dock_device(handle)) {
 332                 unsigned long long sun;
 333                 int retval;
 334
 335                 bridge->nr_slots++;
 336                 status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
 337                 if (ACPI_FAILURE(status))
 338                         sun = bridge->nr_slots;
 339
 340                 pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
 341                     sun, pci_domain_nr(pbus), pbus->number, device);
 342
 343                 retval = acpiphp_register_hotplug_slot(slot, sun);
 344                 if (retval) {
 345                         slot->slot = NULL;
 346                         bridge->nr_slots--;
 347                         if (retval == -EBUSY)
 348                                 pr_warn("Slot %llu already registered by another "
 349                                         "hotplug driver\n", sun);
 350                         else
 351                                 pr_warn("acpiphp_register_hotplug_slot failed "
 352                                         "(err code = 0x%x)\n", retval);
 353                 }
 354                 /* Even if the slot registration fails, we can still use it. */
 355         }
 356
 357  slot_found:
 358         newfunc->slot = slot;
 359         list_add_tail(&newfunc->sibling, &slot->funcs);
 360
 361         if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
 362                                        &val, 60*1000))
 363                 slot->flags |= SLOT_ENABLED;
 364
 365         if (is_dock_device(handle)) {
 366                 /* we don't want to call this device's _EJ0
 367                  * because we want the dock notify handler
 368                  * to call it after it calls _DCK
 369                  */
 370                 newfunc->flags &= ~FUNC_HAS_EJ0;
 371                 if (register_hotplug_dock_device(handle,
 372                         &acpiphp_dock_ops, context,
 373                         acpiphp_dock_init, acpiphp_dock_release))
 374                         pr_debug("failed to register dock device\n");
 375         }
 376
 377         /* install notify handler */
 378         if (!(newfunc->flags & FUNC_HAS_DCK)) {
 379                 status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 380                                                      handle_hotplug_event,
 381                                                      context);
 382                 if (ACPI_FAILURE(status))
 383                         acpi_handle_err(handle,
 384                                         "failed to install notify handler\n");
 385         }
 386
 387         return AE_OK;
 388
 389  err:
 390         mutex_lock(&acpiphp_context_lock);
 391         acpiphp_put_context(context);
 392         mutex_unlock(&acpiphp_context_lock);
 393         return status;
 394 }
 395
 396 static struct acpiphp_bridge *acpiphp_handle_to_bridge(acpi_handle handle)
 397 {
 398         struct acpiphp_context *context;
 399         struct acpiphp_bridge *bridge = NULL;
 400
 401         mutex_lock(&acpiphp_context_lock);
 402         context = acpiphp_get_context(handle);
 403         if (context) {
 404                 bridge = context->bridge;
 405                 if (bridge)
 406                         get_bridge(bridge);
 407
 408                 acpiphp_put_context(context);
 409         }
 410         mutex_unlock(&acpiphp_context_lock);
 411         return bridge;
 412 }
 413
 414 static void cleanup_bridge(struct acpiphp_bridge *bridge)
 415 {
 416         struct acpiphp_slot *slot;
 417         struct acpiphp_func *func;
 418         acpi_status status;
 419
 420         list_for_each_entry(slot, &bridge->slots, node) {
 421                 list_for_each_entry(func, &slot->funcs, sibling) {
 422                         acpi_handle handle = func_to_handle(func);
 423
 424                         if (is_dock_device(handle))
 425                                 unregister_hotplug_dock_device(handle);
 426
 427                         if (!(func->flags & FUNC_HAS_DCK)) {
 428                                 status = acpi_remove_notify_handler(handle,
 429                                                         ACPI_SYSTEM_NOTIFY,
 430                                                         handle_hotplug_event);
 431                                 if (ACPI_FAILURE(status))
 432                                         pr_err("failed to remove notify handler\n");
 433                         }
 434                 }
 435                 slot->flags |= SLOT_IS_GOING_AWAY;
 436                 if (slot->slot)
 437                         acpiphp_unregister_hotplug_slot(slot);
 438         }
 439
 440         mutex_lock(&bridge_mutex);
 441         list_del(&bridge->list);
 442         mutex_unlock(&bridge_mutex);
 443
 444         bridge->is_going_away = true;
 445 }
 446
 447 /**
 448  * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
 449  * @bus: bus to start search with
 450  */
 451 static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
 452 {
 453         struct list_head *tmp;
 454         unsigned char max, n;
 455
 456         /*
 457          * pci_bus_max_busnr will return the highest
 458          * reserved busnr for all these children.
 459          * that is equivalent to the bus->subordinate
 460          * value.  We don't want to use the parent's
 461          * bus->subordinate value because it could have
 462          * padding in it.
 463          */
 464         max = bus->busn_res.start;
 465
 466         list_for_each(tmp, &bus->children) {
 467                 n = pci_bus_max_busnr(pci_bus_b(tmp));
 468                 if (n > max)
 469                         max = n;
 470         }
 471         return max;
 472 }
 473
 474 /**
 475  * acpiphp_bus_trim - Trim device objects in an ACPI namespace subtree.
 476  * @handle: ACPI device object handle to start from.
 477  */
 478 static void acpiphp_bus_trim(acpi_handle handle)
 479 {
 480         struct acpi_device *adev = NULL;
 481
 482         acpi_bus_get_device(handle, &adev);
 483         if (adev)
 484                 acpi_bus_trim(adev);
 485 }
 486
 487 /**
 488  * acpiphp_bus_add - Scan ACPI namespace subtree.
 489  * @handle: ACPI object handle to start the scan from.
 490  */
 491 static void acpiphp_bus_add(acpi_handle handle)
 492 {
 493         struct acpi_device *adev = NULL;
 494
 495         acpi_bus_scan(handle);
 496         acpi_bus_get_device(handle, &adev);
 497         if (acpi_device_enumerated(adev))
 498                 acpi_device_set_power(adev, ACPI_STATE_D0);
 499 }
 500
 501 static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
 502 {
 503         struct acpiphp_func *func;
 504         union acpi_object params[2];
 505         struct acpi_object_list arg_list;
 506
 507         list_for_each_entry(func, &slot->funcs, sibling) {
 508                 arg_list.count = 2;
 509                 arg_list.pointer = params;
 510                 params[0].type = ACPI_TYPE_INTEGER;
 511                 params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
 512                 params[1].type = ACPI_TYPE_INTEGER;
 513                 params[1].integer.value = 1;
 514                 /* _REG is optional, we don't care about if there is failure */
 515                 acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
 516                                      NULL);
 517         }
 518 }
 519
 520 static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
 521 {
 522         struct acpiphp_func *func;
 523
 524         /* quirk, or pcie could set it already */
 525         if (dev->is_hotplug_bridge)
 526                 return;
 527
 528         list_for_each_entry(func, &slot->funcs, sibling) {
 529                 if (PCI_FUNC(dev->devfn) == func->function) {
 530                         dev->is_hotplug_bridge = 1;
 531                         break;
 532                 }
 533         }
 534 }
 535
 536 static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
 537 {
 538         struct acpiphp_func *func;
 539
 540         list_for_each_entry(func, &slot->funcs, sibling)
 541                 acpiphp_bus_add(func_to_handle(func));
 542
 543         return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
 544 }
 545
 546 /**
 547  * enable_slot - enable, configure a slot
 548  * @slot: slot to be enabled
 549  *
 550  * This function should be called per *physical slot*,
 551  * not per each slot object in ACPI namespace.
 552  */
 553 static void __ref enable_slot(struct acpiphp_slot *slot)
 554 {
 555         struct pci_dev *dev;
 556         struct pci_bus *bus = slot->bus;
 557         struct acpiphp_func *func;
 558         int max, pass;
 559         LIST_HEAD(add_list);
 560
 561         acpiphp_rescan_slot(slot);
 562         max = acpiphp_max_busnr(bus);
 563         for (pass = 0; pass < 2; pass++) {
 564                 list_for_each_entry(dev, &bus->devices, bus_list) {
 565                         if (PCI_SLOT(dev->devfn) != slot->device)
 566                                 continue;
 567
 568                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 569                             dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 570                                 max = pci_scan_bridge(bus, dev, max, pass);
 571                                 if (pass && dev->subordinate) {
 572                                         check_hotplug_bridge(slot, dev);
 573                                         pcibios_resource_survey_bus(dev->subordinate);
 574                                         __pci_bus_size_bridges(dev->subordinate,
 575                                                                &add_list);
 576                                 }
 577                         }
 578                 }
 579         }
 580         __pci_bus_assign_resources(bus, &add_list, NULL);
 581
 582         acpiphp_sanitize_bus(bus);
 583         acpiphp_set_hpp_values(bus);
 584         acpiphp_set_acpi_region(slot);
 585
 586         list_for_each_entry(dev, &bus->devices, bus_list) {
 587                 /* Assume that newly added devices are powered on already. */
 588                 if (!dev->is_added)
 589                         dev->current_state = PCI_D0;
 590         }
 591
 592         pci_bus_add_devices(bus);
 593
 594         slot->flags |= SLOT_ENABLED;
 595         list_for_each_entry(func, &slot->funcs, sibling) {
 596                 dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
 597                                                   func->function));
 598                 if (!dev) {
 599                         /* Do not set SLOT_ENABLED flag if some funcs
 600                            are not added. */
 601                         slot->flags &= (~SLOT_ENABLED);
 602                         continue;
 603                 }
 604         }
 605 }
 606
 607 /* return first device in slot, acquiring a reference on it */
 608 static struct pci_dev *dev_in_slot(struct acpiphp_slot *slot)
 609 {
 610         struct pci_bus *bus = slot->bus;
 611         struct pci_dev *dev;
 612         struct pci_dev *ret = NULL;
 613
 614         down_read(&pci_bus_sem);
 615         list_for_each_entry(dev, &bus->devices, bus_list)
 616                 if (PCI_SLOT(dev->devfn) == slot->device) {
 617                         ret = pci_dev_get(dev);
 618                         break;
 619                 }
 620         up_read(&pci_bus_sem);
 621
 622         return ret;
 623 }
 624
 625 /**
 626  * disable_slot - disable a slot
 627  * @slot: ACPI PHP slot
 628  */
 629 static void disable_slot(struct acpiphp_slot *slot)
 630 {
 631         struct acpiphp_func *func;
 632         struct pci_dev *pdev;
 633
 634         /*
 635          * enable_slot() enumerates all functions in this device via
 636          * pci_scan_slot(), whether they have associated ACPI hotplug
 637          * methods (_EJ0, etc.) or not.  Therefore, we remove all functions
 638          * here.
 639          */
 640         while ((pdev = dev_in_slot(slot))) {
 641                 pci_stop_and_remove_bus_device(pdev);
 642                 pci_dev_put(pdev);
 643         }
 644
 645         list_for_each_entry(func, &slot->funcs, sibling)
 646                 acpiphp_bus_trim(func_to_handle(func));
 647
 648         slot->flags &= (~SLOT_ENABLED);
 649 }
 650
 651 static bool acpiphp_no_hotplug(acpi_handle handle)
 652 {
 653         struct acpi_device *adev = NULL;
 654
 655         acpi_bus_get_device(handle, &adev);
 656         return adev && adev->flags.no_hotplug;
 657 }
 658
 659 static bool slot_no_hotplug(struct acpiphp_slot *slot)
 660 {
 661         struct acpiphp_func *func;
 662
 663         list_for_each_entry(func, &slot->funcs, sibling)
 664                 if (acpiphp_no_hotplug(func_to_handle(func)))
 665                         return true;
 666
 667         return false;
 668 }
 669
 670 /**
 671  * get_slot_status - get ACPI slot status
 672  * @slot: ACPI PHP slot
 673  *
 674  * If a slot has _STA for each function and if any one of them
 675  * returned non-zero status, return it.
 676  *
 677  * If a slot doesn't have _STA and if any one of its functions'
 678  * configuration space is configured, return 0x0f as a _STA.
 679  *
 680  * Otherwise return 0.
 681  */
 682 static unsigned int get_slot_status(struct acpiphp_slot *slot)
 683 {
 684         unsigned long long sta = 0;
 685         struct acpiphp_func *func;
 686
 687         list_for_each_entry(func, &slot->funcs, sibling) {
 688                 if (func->flags & FUNC_HAS_STA) {
 689                         acpi_status status;
 690
 691                         status = acpi_evaluate_integer(func_to_handle(func),
 692                                                        "_STA", NULL, &sta);
 693                         if (ACPI_SUCCESS(status) && sta)
 694                                 break;
 695                 } else {
 696                         u32 dvid;
 697
 698                         pci_bus_read_config_dword(slot->bus,
 699                                                   PCI_DEVFN(slot->device,
 700                                                             func->function),
 701                                                   PCI_VENDOR_ID, &dvid);
 702                         if (dvid != 0xffffffff) {
 703                                 sta = ACPI_STA_ALL;
 704                                 break;
 705                         }
 706                 }
 707         }
 708
 709         return (unsigned int)sta;
 710 }
 711
 712 /**
 713  * trim_stale_devices - remove PCI devices that are not responding.
 714  * @dev: PCI device to start walking the hierarchy from.
 715  */
 716 static void trim_stale_devices(struct pci_dev *dev)
 717 {
 718         acpi_handle handle = ACPI_HANDLE(&dev->dev);
 719         struct pci_bus *bus = dev->subordinate;
 720         bool alive = false;
 721
 722         if (handle) {
 723                 acpi_status status;
 724                 unsigned long long sta;
 725
 726                 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 727                 alive = (ACPI_SUCCESS(status) && sta == ACPI_STA_ALL)
 728                         || acpiphp_no_hotplug(handle);
 729         }
 730         if (!alive) {
 731                 u32 v;
 732
 733                 /* Check if the device responds. */
 734                 alive = pci_bus_read_dev_vendor_id(dev->bus, dev->devfn, &v, 0);
 735         }
 736         if (!alive) {
 737                 pci_stop_and_remove_bus_device(dev);
 738                 if (handle)
 739                         acpiphp_bus_trim(handle);
 740         } else if (bus) {
 741                 struct pci_dev *child, *tmp;
 742
 743                 /* The device is a bridge. so check the bus below it. */
 744                 pm_runtime_get_sync(&dev->dev);
 745                 list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
 746                         trim_stale_devices(child);
 747
 748                 pm_runtime_put(&dev->dev);
 749         }
 750 }
 751
 752 /**
 753  * acpiphp_check_bridge - re-enumerate devices
 754  * @bridge: where to begin re-enumeration
 755  *
 756  * Iterate over all slots under this bridge and make sure that if a
 757  * card is present they are enabled, and if not they are disabled.
 758  */
 759 static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
 760 {
 761         struct acpiphp_slot *slot;
 762
 763         /* Bail out if the bridge is going away. */
 764         if (bridge->is_going_away)
 765                 return;
 766
 767         list_for_each_entry(slot, &bridge->slots, node) {
 768                 struct pci_bus *bus = slot->bus;
 769                 struct pci_dev *dev, *tmp;
 770
 771                 mutex_lock(&slot->crit_sect);
 772                 if (slot_no_hotplug(slot)) {
 773                         ; /* do nothing */
 774                 } else if (get_slot_status(slot) == ACPI_STA_ALL) {
 775                         /* remove stale devices if any */
 776                         list_for_each_entry_safe_reverse(dev, tmp,
 777                                                          &bus->devices, bus_list)
 778                                 if (PCI_SLOT(dev->devfn) == slot->device)
 779                                         trim_stale_devices(dev);
 780
 781                         /* configure all functions */
 782                         enable_slot(slot);
 783                 } else {
 784                         disable_slot(slot);
 785                 }
 786                 mutex_unlock(&slot->crit_sect);
 787         }
 788 }
 789
 790 static void acpiphp_set_hpp_values(struct pci_bus *bus)
 791 {
 792         struct pci_dev *dev;
 793
 794         list_for_each_entry(dev, &bus->devices, bus_list)
 795                 pci_configure_slot(dev);
 796 }
 797
 798 /*
 799  * Remove devices for which we could not assign resources, call
 800  * arch specific code to fix-up the bus
 801  */
 802 static void acpiphp_sanitize_bus(struct pci_bus *bus)
 803 {
 804         struct pci_dev *dev, *tmp;
 805         int i;
 806         unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
 807
 808         list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
 809                 for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
 810                         struct resource *res = &dev->resource[i];
 811                         if ((res->flags & type_mask) && !res->start &&
 812                                         res->end) {
 813                                 /* Could not assign a required resources
 814                                  * for this device, remove it */
 815                                 pci_stop_and_remove_bus_device(dev);
 816                                 break;
 817                         }
 818                 }
 819         }
 820 }
 821
 822 /*
 823  * ACPI event handlers
 824  */
 825
 826 void acpiphp_check_host_bridge(acpi_handle handle)
 827 {
 828         struct acpiphp_bridge *bridge;
 829
 830         bridge = acpiphp_handle_to_bridge(handle);
 831         if (bridge) {
 832                 pci_lock_rescan_remove();
 833
 834                 acpiphp_check_bridge(bridge);
 835
 836                 pci_unlock_rescan_remove();
 837                 put_bridge(bridge);
 838         }
 839 }
 840
 841 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
 842
 843 static void hotplug_event(acpi_handle handle, u32 type, void *data)
 844 {
 845         struct acpiphp_context *context = data;
 846         struct acpiphp_func *func = &context->func;
 847         struct acpiphp_bridge *bridge;
 848         char objname[64];
 849         struct acpi_buffer buffer = { .length = sizeof(objname),
 850                                       .pointer = objname };
 851
 852         mutex_lock(&acpiphp_context_lock);
 853         bridge = context->bridge;
 854         if (bridge)
 855                 get_bridge(bridge);
 856
 857         mutex_unlock(&acpiphp_context_lock);
 858
 859         pci_lock_rescan_remove();
 860         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 861
 862         switch (type) {
 863         case ACPI_NOTIFY_BUS_CHECK:
 864                 /* bus re-enumerate */
 865                 pr_debug("%s: Bus check notify on %s\n", __func__, objname);
 866                 pr_debug("%s: re-enumerating slots under %s\n",
 867                          __func__, objname);
 868                 if (bridge) {
 869                         acpiphp_check_bridge(bridge);
 870                 } else {
 871                         struct acpiphp_slot *slot = func->slot;
 872
 873                         if (slot->flags & SLOT_IS_GOING_AWAY)
 874                                 break;
 875
 876                         mutex_lock(&slot->crit_sect);
 877                         enable_slot(slot);
 878                         mutex_unlock(&slot->crit_sect);
 879                 }
 880                 break;
 881
 882         case ACPI_NOTIFY_DEVICE_CHECK:
 883                 /* device check */
 884                 pr_debug("%s: Device check notify on %s\n", __func__, objname);
 885                 if (bridge) {
 886                         acpiphp_check_bridge(bridge);
 887                 } else {
 888                         struct acpiphp_slot *slot = func->slot;
 889                         int ret;
 890
 891                         if (slot->flags & SLOT_IS_GOING_AWAY)
 892                                 break;
 893
 894                         /*
 895                          * Check if anything has changed in the slot and rescan
 896                          * from the parent if that's the case.
 897                          */
 898                         mutex_lock(&slot->crit_sect);
 899                         ret = acpiphp_rescan_slot(slot);
 900                         mutex_unlock(&slot->crit_sect);
 901                         if (ret)
 902                                 acpiphp_check_bridge(func->parent);
 903                 }
 904                 break;
 905
 906         case ACPI_NOTIFY_EJECT_REQUEST:
 907                 /* request device eject */
 908                 pr_debug("%s: Device eject notify on %s\n", __func__, objname);
 909                 acpiphp_disable_and_eject_slot(func->slot);
 910                 break;
 911         }
 912
 913         pci_unlock_rescan_remove();
 914         if (bridge)
 915                 put_bridge(bridge);
 916 }
 917
 918 static void hotplug_event_work(void *data, u32 type)
 919 {
 920         struct acpiphp_context *context = data;
 921         acpi_handle handle = context->handle;
 922
 923         acpi_scan_lock_acquire();
 924
 925         hotplug_event(handle, type, context);
 926
 927         acpi_scan_lock_release();
 928         acpi_evaluate_hotplug_ost(handle, type, ACPI_OST_SC_SUCCESS, NULL);
 929         put_bridge(context->func.parent);
 930 }
 931
 932 /**
 933  * handle_hotplug_event - handle ACPI hotplug event
 934  * @handle: Notify()'ed acpi_handle
 935  * @type: Notify code
 936  * @data: pointer to acpiphp_context structure
 937  *
 938  * Handles ACPI event notification on slots.
 939  */
 940 static void handle_hotplug_event(acpi_handle handle, u32 type, void *data)
 941 {
 942         struct acpiphp_context *context;
 943         u32 ost_code = ACPI_OST_SC_SUCCESS;
 944
 945         switch (type) {
 946         case ACPI_NOTIFY_BUS_CHECK:
 947         case ACPI_NOTIFY_DEVICE_CHECK:
 948                 break;
 949         case ACPI_NOTIFY_EJECT_REQUEST:
 950                 ost_code = ACPI_OST_SC_EJECT_IN_PROGRESS;
 951                 acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
 952                 break;
 953
 954         case ACPI_NOTIFY_DEVICE_WAKE:
 955                 return;
 956
 957         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
 958                 acpi_handle_err(handle, "Device cannot be configured due "
 959                                 "to a frequency mismatch\n");
 960                 goto out;
 961
 962         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
 963                 acpi_handle_err(handle, "Device cannot be configured due "
 964                                 "to a bus mode mismatch\n");
 965                 goto out;
 966
 967         case ACPI_NOTIFY_POWER_FAULT:
 968                 acpi_handle_err(handle, "Device has suffered a power fault\n");
 969                 goto out;
 970
 971         default:
 972                 acpi_handle_warn(handle, "Unsupported event type 0x%x\n", type);
 973                 ost_code = ACPI_OST_SC_UNRECOGNIZED_NOTIFY;
 974                 goto out;
 975         }
 976
 977         mutex_lock(&acpiphp_context_lock);
 978         context = acpiphp_get_context(handle);
 979         if (context && !WARN_ON(context->handle != handle)) {
 980                 get_bridge(context->func.parent);
 981                 acpiphp_put_context(context);
 982                 acpi_hotplug_execute(hotplug_event_work, context, type);
 983                 mutex_unlock(&acpiphp_context_lock);
 984                 return;
 985         }
 986         mutex_unlock(&acpiphp_context_lock);
 987         ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 988
 989  out:
 990         acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
 991 }
 992
 993 /*
 994  * Create hotplug slots for the PCI bus.
 995  * It should always return 0 to avoid skipping following notifiers.
 996  */
 997 void acpiphp_enumerate_slots(struct pci_bus *bus)
 998 {
 999         struct acpiphp_bridge *bridge;
1000         acpi_handle handle;
1001         acpi_status status;
1002
1003         if (acpiphp_disabled)
1004                 return;
1005
1006         handle = ACPI_HANDLE(bus->bridge);
1007         if (!handle)
1008                 return;
1009
1010         bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
1011         if (!bridge) {
1012                 acpi_handle_err(handle, "No memory for bridge object\n");
1013                 return;
1014         }
1015
1016         INIT_LIST_HEAD(&bridge->slots);
1017         kref_init(&bridge->ref);
1018         bridge->pci_dev = pci_dev_get(bus->self);
1019         bridge->pci_bus = bus;
1020
1021         /*
1022          * Grab a ref to the subordinate PCI bus in case the bus is
1023          * removed via PCI core logical hotplug. The ref pins the bus
1024          * (which we access during module unload).
1025          */
1026         get_device(&bus->dev);
1027
1028         if (!pci_is_root_bus(bridge->pci_bus)) {
1029                 struct acpiphp_context *context;
1030
1031                 /*
1032                  * This bridge should have been registered as a hotplug function
1033                  * under its parent, so the context should be there, unless the
1034                  * parent is going to be handled by pciehp, in which case this
1035                  * bridge is not interesting to us either.
1036                  */
1037                 mutex_lock(&acpiphp_context_lock);
1038                 context = acpiphp_get_context(handle);
1039                 if (!context) {
1040                         mutex_unlock(&acpiphp_context_lock);
1041                         put_device(&bus->dev);
1042                         pci_dev_put(bridge->pci_dev);
1043                         kfree(bridge);
1044                         return;
1045                 }
1046                 bridge->context = context;
1047                 context->bridge = bridge;
1048                 /* Get a reference to the parent bridge. */
1049                 get_bridge(context->func.parent);
1050                 mutex_unlock(&acpiphp_context_lock);
1051         }
1052
1053         /* must be added to the list prior to calling register_slot */
1054         mutex_lock(&bridge_mutex);
1055         list_add(&bridge->list, &bridge_list);
1056         mutex_unlock(&bridge_mutex);
1057
1058         /* register all slot objects under this bridge */
1059         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
1060                                      register_slot, NULL, bridge, NULL);
1061         if (ACPI_FAILURE(status)) {
1062                 acpi_handle_err(handle, "failed to register slots\n");
1063                 cleanup_bridge(bridge);
1064                 put_bridge(bridge);
1065         }
1066 }
1067
1068 /* Destroy hotplug slots associated with the PCI bus */
1069 void acpiphp_remove_slots(struct pci_bus *bus)
1070 {
1071         struct acpiphp_bridge *bridge;
1072
1073         if (acpiphp_disabled)
1074                 return;
1075
1076         mutex_lock(&bridge_mutex);
1077         list_for_each_entry(bridge, &bridge_list, list)
1078                 if (bridge->pci_bus == bus) {
1079                         mutex_unlock(&bridge_mutex);
1080                         cleanup_bridge(bridge);
1081                         put_bridge(bridge);
1082                         return;
1083                 }
1084
1085         mutex_unlock(&bridge_mutex);
1086 }
1087
1088 /**
1089  * acpiphp_enable_slot - power on slot
1090  * @slot: ACPI PHP slot
1091  */
1092 int acpiphp_enable_slot(struct acpiphp_slot *slot)
1093 {
1094         pci_lock_rescan_remove();
1095
1096         if (slot->flags & SLOT_IS_GOING_AWAY)
1097                 return -ENODEV;
1098
1099         mutex_lock(&slot->crit_sect);
1100         /* configure all functions */
1101         if (!(slot->flags & SLOT_ENABLED))
1102                 enable_slot(slot);
1103
1104         mutex_unlock(&slot->crit_sect);
1105
1106         pci_unlock_rescan_remove();
1107         return 0;
1108 }
1109
1110 /**
1111  * acpiphp_disable_and_eject_slot - power off and eject slot
1112  * @slot: ACPI PHP slot
1113  */
1114 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
1115 {
1116         struct acpiphp_func *func;
1117
1118         if (slot->flags & SLOT_IS_GOING_AWAY)
1119                 return -ENODEV;
1120
1121         mutex_lock(&slot->crit_sect);
1122
1123         /* unconfigure all functions */
1124         disable_slot(slot);
1125
1126         list_for_each_entry(func, &slot->funcs, sibling)
1127                 if (func->flags & FUNC_HAS_EJ0) {
1128                         acpi_handle handle = func_to_handle(func);
1129
1130                         if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
1131                                 acpi_handle_err(handle, "_EJ0 failed\n");
1132
1133                         break;
1134                 }
1135
1136         mutex_unlock(&slot->crit_sect);
1137         return 0;
1138 }
1139
1140 int acpiphp_disable_slot(struct acpiphp_slot *slot)
1141 {
1142         int ret;
1143
1144         pci_lock_rescan_remove();
1145         ret = acpiphp_disable_and_eject_slot(slot);
1146         pci_unlock_rescan_remove();
1147         return ret;
1148 }
1149
1150 /*
1151  * slot enabled:  1
1152  * slot disabled: 0
1153  */
1154 u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1155 {
1156         return (slot->flags & SLOT_ENABLED);
1157 }
1158
1159 /*
1160  * latch   open:  1
1161  * latch closed:  0
1162  */
1163 u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1164 {
1165         return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1166 }
1167
1168 /*
1169  * adapter presence : 1
1170  *          absence : 0
1171  */
1172 u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1173 {
1174         return !!get_slot_status(slot);
1175 }