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v3.15
   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
  59static LIST_HEAD(bridge_list);
  60static DEFINE_MUTEX(bridge_mutex);
  61
  62static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
  63static void acpiphp_post_dock_fixup(struct acpi_device *adev);
  64static void acpiphp_sanitize_bus(struct pci_bus *bus);
  65static void acpiphp_set_hpp_values(struct pci_bus *bus);
  66static void hotplug_event(u32 type, struct acpiphp_context *context);
  67static void free_bridge(struct kref *kref);
  68
  69/**
  70 * acpiphp_init_context - Create hotplug context and grab a reference to it.
  71 * @adev: ACPI device object to create the context for.
  72 *
  73 * Call under acpi_hp_context_lock.
  74 */
  75static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
  76{
  77	struct acpiphp_context *context;
  78
  79	context = kzalloc(sizeof(*context), GFP_KERNEL);
  80	if (!context)
  81		return NULL;
  82
  83	context->refcount = 1;
  84	acpi_set_hp_context(adev, &context->hp, acpiphp_hotplug_notify, NULL,
  85			    acpiphp_post_dock_fixup);
 
  86	return context;
  87}
  88
  89/**
  90 * acpiphp_get_context - Get hotplug context and grab a reference to it.
  91 * @adev: ACPI device object to get the context for.
  92 *
  93 * Call under acpi_hp_context_lock.
  94 */
  95static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
  96{
  97	struct acpiphp_context *context;
  98
  99	if (!adev->hp)
 100		return NULL;
 101
 102	context = to_acpiphp_context(adev->hp);
 103	context->refcount++;
 104	return context;
 105}
 106
 107/**
 108 * acpiphp_put_context - Drop a reference to ACPI hotplug context.
 109 * @context: ACPI hotplug context to drop a reference to.
 110 *
 111 * The context object is removed if there are no more references to it.
 112 *
 113 * Call under acpi_hp_context_lock.
 114 */
 115static void acpiphp_put_context(struct acpiphp_context *context)
 116{
 117	if (--context->refcount)
 118		return;
 119
 120	WARN_ON(context->bridge);
 121	context->hp.self->hp = NULL;
 122	kfree(context);
 123}
 124
 125static inline void get_bridge(struct acpiphp_bridge *bridge)
 126{
 127	kref_get(&bridge->ref);
 128}
 129
 130static inline void put_bridge(struct acpiphp_bridge *bridge)
 131{
 132	kref_put(&bridge->ref, free_bridge);
 133}
 134
 135static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
 136{
 137	struct acpiphp_context *context;
 138
 139	acpi_lock_hp_context();
 140	context = acpiphp_get_context(adev);
 141	if (!context || context->func.parent->is_going_away) {
 142		acpi_unlock_hp_context();
 143		return NULL;
 144	}
 145	get_bridge(context->func.parent);
 146	acpiphp_put_context(context);
 147	acpi_unlock_hp_context();
 148	return context;
 149}
 150
 151static void acpiphp_let_context_go(struct acpiphp_context *context)
 152{
 153	put_bridge(context->func.parent);
 154}
 155
 156static void free_bridge(struct kref *kref)
 157{
 158	struct acpiphp_context *context;
 159	struct acpiphp_bridge *bridge;
 160	struct acpiphp_slot *slot, *next;
 161	struct acpiphp_func *func, *tmp;
 162
 163	acpi_lock_hp_context();
 164
 165	bridge = container_of(kref, struct acpiphp_bridge, ref);
 166
 167	list_for_each_entry_safe(slot, next, &bridge->slots, node) {
 168		list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
 169			acpiphp_put_context(func_to_context(func));
 170
 171		kfree(slot);
 172	}
 173
 174	context = bridge->context;
 175	/* Root bridges will not have hotplug context. */
 176	if (context) {
 177		/* Release the reference taken by acpiphp_enumerate_slots(). */
 178		put_bridge(context->func.parent);
 179		context->bridge = NULL;
 180		acpiphp_put_context(context);
 181	}
 182
 183	put_device(&bridge->pci_bus->dev);
 184	pci_dev_put(bridge->pci_dev);
 185	kfree(bridge);
 186
 187	acpi_unlock_hp_context();
 188}
 189
 190/**
 191 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
 192 * @adev: ACPI device object corresponding to a PCI device.
 193 *
 194 * TBD - figure out a way to only call fixups for systems that require them.
 195 */
 196static void acpiphp_post_dock_fixup(struct acpi_device *adev)
 197{
 198	struct acpiphp_context *context = acpiphp_grab_context(adev);
 199	struct pci_bus *bus;
 200	u32 buses;
 201
 202	if (!context)
 203		return;
 204
 205	bus = context->func.slot->bus;
 206	if (!bus->self)
 207		goto out;
 208
 209	/* fixup bad _DCK function that rewrites
 210	 * secondary bridge on slot
 211	 */
 212	pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
 213
 214	if (((buses >> 8) & 0xff) != bus->busn_res.start) {
 215		buses = (buses & 0xff000000)
 216			| ((unsigned int)(bus->primary)     <<  0)
 217			| ((unsigned int)(bus->busn_res.start)   <<  8)
 218			| ((unsigned int)(bus->busn_res.end) << 16);
 219		pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
 220	}
 221
 222 out:
 223	acpiphp_let_context_go(context);
 224}
 225
 226/* Check whether the PCI device is managed by native PCIe hotplug driver */
 227static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
 228{
 229	u32 reg32;
 230	acpi_handle tmp;
 231	struct acpi_pci_root *root;
 232
 233	/* Check whether the PCIe port supports native PCIe hotplug */
 234	if (pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32))
 235		return false;
 236	if (!(reg32 & PCI_EXP_SLTCAP_HPC))
 237		return false;
 238
 239	/*
 240	 * Check whether native PCIe hotplug has been enabled for
 241	 * this PCIe hierarchy.
 242	 */
 243	tmp = acpi_find_root_bridge_handle(pdev);
 244	if (!tmp)
 245		return false;
 246	root = acpi_pci_find_root(tmp);
 247	if (!root)
 248		return false;
 249	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
 250		return false;
 251
 252	return true;
 253}
 254
 255/**
 256 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
 257 * @handle: ACPI handle of the object to add a context to.
 258 * @lvl: Not used.
 259 * @data: The object's parent ACPIPHP bridge.
 260 * @rv: Not used.
 261 */
 262static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
 263				       void **rv)
 264{
 265	struct acpiphp_bridge *bridge = data;
 266	struct acpiphp_context *context;
 267	struct acpi_device *adev;
 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	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
 278	if (ACPI_FAILURE(status)) {
 279		if (status != AE_NOT_FOUND)
 280			acpi_handle_warn(handle,
 281				"can't evaluate _ADR (%#x)\n", status);
 282		return AE_OK;
 283	}
 284	if (acpi_bus_get_device(handle, &adev))
 285		return AE_OK;
 286
 287	device = (adr >> 16) & 0xffff;
 288	function = adr & 0xffff;
 289
 290	acpi_lock_hp_context();
 291	context = acpiphp_init_context(adev);
 292	if (!context) {
 293		acpi_unlock_hp_context();
 294		acpi_handle_err(handle, "No hotplug context\n");
 295		return AE_NOT_EXIST;
 296	}
 297	newfunc = &context->func;
 298	newfunc->function = function;
 299	newfunc->parent = bridge;
 300	acpi_unlock_hp_context();
 301
 302	/*
 303	 * If this is a dock device, its _EJ0 should be executed by the dock
 304	 * notify handler after calling _DCK.
 305	 */
 306	if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
 307		newfunc->flags = FUNC_HAS_EJ0;
 308
 309	if (acpi_has_method(handle, "_STA"))
 310		newfunc->flags |= FUNC_HAS_STA;
 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		acpi_lock_hp_context();
 320		acpiphp_put_context(context);
 321		acpi_unlock_hp_context();
 322		return AE_NO_MEMORY;
 323	}
 324
 325	slot->bus = bridge->pci_bus;
 326	slot->device = device;
 327	INIT_LIST_HEAD(&slot->funcs);
 328
 329	list_add_tail(&slot->node, &bridge->slots);
 330
 331	/*
 332	 * Expose slots to user space for functions that have _EJ0 or _RMV or
 333	 * are located in dock stations.  Do not expose them for devices handled
 334	 * by the native PCIe hotplug (PCIeHP), becuase that code is supposed to
 335	 * expose slots to user space in those cases.
 336	 */
 337	if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
 338	    && !(pdev && device_is_managed_by_native_pciehp(pdev))) {
 339		unsigned long long sun;
 340		int retval;
 341
 342		bridge->nr_slots++;
 343		status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
 344		if (ACPI_FAILURE(status))
 345			sun = bridge->nr_slots;
 346
 347		pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
 348		    sun, pci_domain_nr(pbus), pbus->number, device);
 349
 350		retval = acpiphp_register_hotplug_slot(slot, sun);
 351		if (retval) {
 352			slot->slot = NULL;
 353			bridge->nr_slots--;
 354			if (retval == -EBUSY)
 355				pr_warn("Slot %llu already registered by another "
 356					"hotplug driver\n", sun);
 357			else
 358				pr_warn("acpiphp_register_hotplug_slot failed "
 359					"(err code = 0x%x)\n", retval);
 360		}
 361		/* Even if the slot registration fails, we can still use it. */
 362	}
 363
 364 slot_found:
 365	newfunc->slot = slot;
 366	list_add_tail(&newfunc->sibling, &slot->funcs);
 367
 368	if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
 369				       &val, 60*1000))
 370		slot->flags |= SLOT_ENABLED;
 371
 372	return AE_OK;
 373}
 374
 375static struct acpiphp_bridge *acpiphp_dev_to_bridge(struct acpi_device *adev)
 376{
 377	struct acpiphp_context *context;
 378	struct acpiphp_bridge *bridge = NULL;
 379
 380	acpi_lock_hp_context();
 381	context = acpiphp_get_context(adev);
 382	if (context) {
 383		bridge = context->bridge;
 384		if (bridge)
 385			get_bridge(bridge);
 386
 387		acpiphp_put_context(context);
 388	}
 389	acpi_unlock_hp_context();
 390	return bridge;
 391}
 392
 393static void cleanup_bridge(struct acpiphp_bridge *bridge)
 394{
 395	struct acpiphp_slot *slot;
 396	struct acpiphp_func *func;
 397
 398	list_for_each_entry(slot, &bridge->slots, node) {
 399		list_for_each_entry(func, &slot->funcs, sibling) {
 400			struct acpi_device *adev = func_to_acpi_device(func);
 401
 402			acpi_lock_hp_context();
 403			adev->hp->notify = NULL;
 404			adev->hp->fixup = NULL;
 405			acpi_unlock_hp_context();
 406		}
 407		slot->flags |= SLOT_IS_GOING_AWAY;
 408		if (slot->slot)
 409			acpiphp_unregister_hotplug_slot(slot);
 410	}
 411
 412	mutex_lock(&bridge_mutex);
 413	list_del(&bridge->list);
 414	mutex_unlock(&bridge_mutex);
 415
 416	acpi_lock_hp_context();
 417	bridge->is_going_away = true;
 418	acpi_unlock_hp_context();
 419}
 420
 421/**
 422 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
 423 * @bus: bus to start search with
 424 */
 425static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
 426{
 427	struct pci_bus *tmp;
 428	unsigned char max, n;
 429
 430	/*
 431	 * pci_bus_max_busnr will return the highest
 432	 * reserved busnr for all these children.
 433	 * that is equivalent to the bus->subordinate
 434	 * value.  We don't want to use the parent's
 435	 * bus->subordinate value because it could have
 436	 * padding in it.
 437	 */
 438	max = bus->busn_res.start;
 439
 440	list_for_each_entry(tmp, &bus->children, node) {
 441		n = pci_bus_max_busnr(tmp);
 442		if (n > max)
 443			max = n;
 444	}
 445	return max;
 446}
 447
 448static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
 449{
 450	struct acpiphp_func *func;
 451	union acpi_object params[2];
 452	struct acpi_object_list arg_list;
 453
 454	list_for_each_entry(func, &slot->funcs, sibling) {
 455		arg_list.count = 2;
 456		arg_list.pointer = params;
 457		params[0].type = ACPI_TYPE_INTEGER;
 458		params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
 459		params[1].type = ACPI_TYPE_INTEGER;
 460		params[1].integer.value = 1;
 461		/* _REG is optional, we don't care about if there is failure */
 462		acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
 463				     NULL);
 464	}
 465}
 466
 467static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
 468{
 469	struct acpiphp_func *func;
 470
 471	/* quirk, or pcie could set it already */
 472	if (dev->is_hotplug_bridge)
 473		return;
 474
 475	list_for_each_entry(func, &slot->funcs, sibling) {
 476		if (PCI_FUNC(dev->devfn) == func->function) {
 477			dev->is_hotplug_bridge = 1;
 478			break;
 479		}
 480	}
 481}
 482
 483static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
 484{
 485	struct acpiphp_func *func;
 486
 487	list_for_each_entry(func, &slot->funcs, sibling) {
 488		struct acpi_device *adev = func_to_acpi_device(func);
 489
 490		acpi_bus_scan(adev->handle);
 491		if (acpi_device_enumerated(adev))
 492			acpi_device_set_power(adev, ACPI_STATE_D0);
 493	}
 494	return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
 495}
 496
 497/**
 498 * enable_slot - enable, configure a slot
 499 * @slot: slot to be enabled
 500 *
 501 * This function should be called per *physical slot*,
 502 * not per each slot object in ACPI namespace.
 503 */
 504static void __ref enable_slot(struct acpiphp_slot *slot)
 505{
 506	struct pci_dev *dev;
 507	struct pci_bus *bus = slot->bus;
 508	struct acpiphp_func *func;
 509	int max, pass;
 510	LIST_HEAD(add_list);
 511
 512	acpiphp_rescan_slot(slot);
 513	max = acpiphp_max_busnr(bus);
 514	for (pass = 0; pass < 2; pass++) {
 515		list_for_each_entry(dev, &bus->devices, bus_list) {
 516			if (PCI_SLOT(dev->devfn) != slot->device)
 517				continue;
 518
 519			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 520			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 521				max = pci_scan_bridge(bus, dev, max, pass);
 522				if (pass && dev->subordinate) {
 523					check_hotplug_bridge(slot, dev);
 524					pcibios_resource_survey_bus(dev->subordinate);
 525					__pci_bus_size_bridges(dev->subordinate,
 526							       &add_list);
 527				}
 528			}
 529		}
 530	}
 531	__pci_bus_assign_resources(bus, &add_list, NULL);
 532
 533	acpiphp_sanitize_bus(bus);
 534	acpiphp_set_hpp_values(bus);
 535	acpiphp_set_acpi_region(slot);
 536
 537	list_for_each_entry(dev, &bus->devices, bus_list) {
 538		/* Assume that newly added devices are powered on already. */
 539		if (!dev->is_added)
 540			dev->current_state = PCI_D0;
 541	}
 542
 543	pci_bus_add_devices(bus);
 544
 545	slot->flags |= SLOT_ENABLED;
 546	list_for_each_entry(func, &slot->funcs, sibling) {
 547		dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
 548						  func->function));
 549		if (!dev) {
 550			/* Do not set SLOT_ENABLED flag if some funcs
 551			   are not added. */
 552			slot->flags &= (~SLOT_ENABLED);
 553			continue;
 554		}
 555	}
 556}
 557
 558/**
 559 * disable_slot - disable a slot
 560 * @slot: ACPI PHP slot
 561 */
 562static void disable_slot(struct acpiphp_slot *slot)
 563{
 564	struct pci_bus *bus = slot->bus;
 565	struct pci_dev *dev, *prev;
 566	struct acpiphp_func *func;
 567
 568	/*
 569	 * enable_slot() enumerates all functions in this device via
 570	 * pci_scan_slot(), whether they have associated ACPI hotplug
 571	 * methods (_EJ0, etc.) or not.  Therefore, we remove all functions
 572	 * here.
 573	 */
 574	list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
 575		if (PCI_SLOT(dev->devfn) == slot->device)
 576			pci_stop_and_remove_bus_device(dev);
 577
 578	list_for_each_entry(func, &slot->funcs, sibling)
 579		acpi_bus_trim(func_to_acpi_device(func));
 580
 581	slot->flags &= (~SLOT_ENABLED);
 582}
 583
 584static bool acpiphp_no_hotplug(struct acpi_device *adev)
 585{
 586	return adev && adev->flags.no_hotplug;
 587}
 588
 589static bool slot_no_hotplug(struct acpiphp_slot *slot)
 590{
 591	struct acpiphp_func *func;
 
 592
 593	list_for_each_entry(func, &slot->funcs, sibling)
 594		if (acpiphp_no_hotplug(func_to_acpi_device(func)))
 595			return true;
 596
 597	return false;
 598}
 599
 600/**
 601 * get_slot_status - get ACPI slot status
 602 * @slot: ACPI PHP slot
 603 *
 604 * If a slot has _STA for each function and if any one of them
 605 * returned non-zero status, return it.
 606 *
 607 * If a slot doesn't have _STA and if any one of its functions'
 608 * configuration space is configured, return 0x0f as a _STA.
 609 *
 610 * Otherwise return 0.
 611 */
 612static unsigned int get_slot_status(struct acpiphp_slot *slot)
 613{
 614	unsigned long long sta = 0;
 615	struct acpiphp_func *func;
 616
 617	list_for_each_entry(func, &slot->funcs, sibling) {
 618		if (func->flags & FUNC_HAS_STA) {
 619			acpi_status status;
 620
 621			status = acpi_evaluate_integer(func_to_handle(func),
 622						       "_STA", NULL, &sta);
 623			if (ACPI_SUCCESS(status) && sta)
 624				break;
 625		} else {
 626			u32 dvid;
 627
 628			pci_bus_read_config_dword(slot->bus,
 629						  PCI_DEVFN(slot->device,
 630							    func->function),
 631						  PCI_VENDOR_ID, &dvid);
 632			if (dvid != 0xffffffff) {
 633				sta = ACPI_STA_ALL;
 634				break;
 635			}
 636		}
 637	}
 638
 639	return (unsigned int)sta;
 640}
 641
 642static inline bool device_status_valid(unsigned int sta)
 643{
 644	/*
 645	 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
 646	 * if the device is valid but does not require a device driver to be
 647	 * loaded (Section 6.3.7 of ACPI 5.0A).
 648	 */
 649	unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
 650	return (sta & mask) == mask;
 651}
 652
 653/**
 654 * trim_stale_devices - remove PCI devices that are not responding.
 655 * @dev: PCI device to start walking the hierarchy from.
 656 */
 657static void trim_stale_devices(struct pci_dev *dev)
 658{
 659	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 660	struct pci_bus *bus = dev->subordinate;
 661	bool alive = false;
 662
 663	if (adev) {
 664		acpi_status status;
 665		unsigned long long sta;
 666
 667		status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
 668		alive = (ACPI_SUCCESS(status) && device_status_valid(sta))
 669			|| acpiphp_no_hotplug(adev);
 670	}
 671	if (!alive)
 672		alive = pci_device_is_present(dev);
 673
 674	if (!alive) {
 675		pci_stop_and_remove_bus_device(dev);
 676		if (adev)
 677			acpi_bus_trim(adev);
 678	} else if (bus) {
 679		struct pci_dev *child, *tmp;
 680
 681		/* The device is a bridge. so check the bus below it. */
 682		pm_runtime_get_sync(&dev->dev);
 683		list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
 684			trim_stale_devices(child);
 685
 686		pm_runtime_put(&dev->dev);
 687	}
 688}
 689
 690/**
 691 * acpiphp_check_bridge - re-enumerate devices
 692 * @bridge: where to begin re-enumeration
 693 *
 694 * Iterate over all slots under this bridge and make sure that if a
 695 * card is present they are enabled, and if not they are disabled.
 696 */
 697static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
 698{
 699	struct acpiphp_slot *slot;
 700
 701	/* Bail out if the bridge is going away. */
 702	if (bridge->is_going_away)
 703		return;
 704
 705	list_for_each_entry(slot, &bridge->slots, node) {
 706		struct pci_bus *bus = slot->bus;
 707		struct pci_dev *dev, *tmp;
 708
 709		if (slot_no_hotplug(slot)) {
 710			; /* do nothing */
 711		} else if (device_status_valid(get_slot_status(slot))) {
 712			/* remove stale devices if any */
 713			list_for_each_entry_safe_reverse(dev, tmp,
 714							 &bus->devices, bus_list)
 715				if (PCI_SLOT(dev->devfn) == slot->device)
 716					trim_stale_devices(dev);
 717
 718			/* configure all functions */
 719			enable_slot(slot);
 720		} else {
 721			disable_slot(slot);
 722		}
 723	}
 724}
 725
 726static void acpiphp_set_hpp_values(struct pci_bus *bus)
 727{
 728	struct pci_dev *dev;
 729
 730	list_for_each_entry(dev, &bus->devices, bus_list)
 731		pci_configure_slot(dev);
 732}
 733
 734/*
 735 * Remove devices for which we could not assign resources, call
 736 * arch specific code to fix-up the bus
 737 */
 738static void acpiphp_sanitize_bus(struct pci_bus *bus)
 739{
 740	struct pci_dev *dev, *tmp;
 741	int i;
 742	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
 743
 744	list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
 745		for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
 746			struct resource *res = &dev->resource[i];
 747			if ((res->flags & type_mask) && !res->start &&
 748					res->end) {
 749				/* Could not assign a required resources
 750				 * for this device, remove it */
 751				pci_stop_and_remove_bus_device(dev);
 752				break;
 753			}
 754		}
 755	}
 756}
 757
 758/*
 759 * ACPI event handlers
 760 */
 761
 762void acpiphp_check_host_bridge(struct acpi_device *adev)
 763{
 764	struct acpiphp_bridge *bridge;
 765
 766	bridge = acpiphp_dev_to_bridge(adev);
 
 
 
 
 
 
 767	if (bridge) {
 768		pci_lock_rescan_remove();
 769
 770		acpiphp_check_bridge(bridge);
 771
 772		pci_unlock_rescan_remove();
 773		put_bridge(bridge);
 774	}
 775}
 776
 777static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
 778
 779static void hotplug_event(u32 type, struct acpiphp_context *context)
 780{
 781	acpi_handle handle = context->hp.self->handle;
 782	struct acpiphp_func *func = &context->func;
 783	struct acpiphp_slot *slot = func->slot;
 784	struct acpiphp_bridge *bridge;
 785
 786	acpi_lock_hp_context();
 787	bridge = context->bridge;
 788	if (bridge)
 789		get_bridge(bridge);
 790
 791	acpi_unlock_hp_context();
 792
 793	pci_lock_rescan_remove();
 794
 795	switch (type) {
 796	case ACPI_NOTIFY_BUS_CHECK:
 797		/* bus re-enumerate */
 798		acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
 799		if (bridge)
 800			acpiphp_check_bridge(bridge);
 801		else if (!(slot->flags & SLOT_IS_GOING_AWAY))
 802			enable_slot(slot);
 803
 804		break;
 805
 806	case ACPI_NOTIFY_DEVICE_CHECK:
 807		/* device check */
 808		acpi_handle_debug(handle, "Device check in %s()\n", __func__);
 809		if (bridge) {
 810			acpiphp_check_bridge(bridge);
 811		} else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
 812			/*
 813			 * Check if anything has changed in the slot and rescan
 814			 * from the parent if that's the case.
 815			 */
 816			if (acpiphp_rescan_slot(slot))
 817				acpiphp_check_bridge(func->parent);
 818		}
 819		break;
 820
 821	case ACPI_NOTIFY_EJECT_REQUEST:
 822		/* request device eject */
 823		acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
 824		acpiphp_disable_and_eject_slot(slot);
 825		break;
 826	}
 827
 828	pci_unlock_rescan_remove();
 829	if (bridge)
 830		put_bridge(bridge);
 831}
 832
 833static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
 834{
 835	struct acpiphp_context *context;
 836
 837	context = acpiphp_grab_context(adev);
 838	if (!context)
 839		return -ENODATA;
 840
 841	hotplug_event(type, context);
 842	acpiphp_let_context_go(context);
 843	return 0;
 844}
 845
 846/**
 847 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
 848 * @bus: PCI bus to enumerate the slots for.
 849 *
 850 * A "slot" is an object associated with a PCI device number.  All functions
 851 * (PCI devices) with the same bus and device number belong to the same slot.
 852 */
 853void acpiphp_enumerate_slots(struct pci_bus *bus)
 854{
 855	struct acpiphp_bridge *bridge;
 856	struct acpi_device *adev;
 857	acpi_handle handle;
 858	acpi_status status;
 859
 860	if (acpiphp_disabled)
 861		return;
 862
 863	adev = ACPI_COMPANION(bus->bridge);
 864	if (!adev)
 865		return;
 866
 867	handle = adev->handle;
 868	bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
 869	if (!bridge) {
 870		acpi_handle_err(handle, "No memory for bridge object\n");
 871		return;
 872	}
 873
 874	INIT_LIST_HEAD(&bridge->slots);
 875	kref_init(&bridge->ref);
 876	bridge->pci_dev = pci_dev_get(bus->self);
 877	bridge->pci_bus = bus;
 878
 879	/*
 880	 * Grab a ref to the subordinate PCI bus in case the bus is
 881	 * removed via PCI core logical hotplug. The ref pins the bus
 882	 * (which we access during module unload).
 883	 */
 884	get_device(&bus->dev);
 885
 886	if (!pci_is_root_bus(bridge->pci_bus)) {
 
 
 
 
 
 
 
 
 
 
 887		struct acpiphp_context *context;
 888
 889		/*
 890		 * This bridge should have been registered as a hotplug function
 891		 * under its parent, so the context should be there, unless the
 892		 * parent is going to be handled by pciehp, in which case this
 893		 * bridge is not interesting to us either.
 894		 */
 895		acpi_lock_hp_context();
 896		context = acpiphp_get_context(adev);
 897		if (!context) {
 898			acpi_unlock_hp_context();
 899			put_device(&bus->dev);
 900			pci_dev_put(bridge->pci_dev);
 901			kfree(bridge);
 902			return;
 903		}
 904		bridge->context = context;
 905		context->bridge = bridge;
 906		/* Get a reference to the parent bridge. */
 907		get_bridge(context->func.parent);
 908		acpi_unlock_hp_context();
 909	}
 
 910
 911	/* Must be added to the list prior to calling acpiphp_add_context(). */
 912	mutex_lock(&bridge_mutex);
 913	list_add(&bridge->list, &bridge_list);
 914	mutex_unlock(&bridge_mutex);
 915
 916	/* register all slot objects under this bridge */
 917	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
 918				     acpiphp_add_context, NULL, bridge, NULL);
 919	if (ACPI_FAILURE(status)) {
 920		acpi_handle_err(handle, "failed to register slots\n");
 921		cleanup_bridge(bridge);
 922		put_bridge(bridge);
 923	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 924}
 925
 926/**
 927 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
 928 * @bus: PCI bus to remove the slot objects for.
 929 */
 930void acpiphp_remove_slots(struct pci_bus *bus)
 931{
 932	struct acpiphp_bridge *bridge;
 933
 934	if (acpiphp_disabled)
 935		return;
 936
 937	mutex_lock(&bridge_mutex);
 938	list_for_each_entry(bridge, &bridge_list, list)
 939		if (bridge->pci_bus == bus) {
 940			mutex_unlock(&bridge_mutex);
 941			cleanup_bridge(bridge);
 942			put_bridge(bridge);
 943			return;
 944		}
 945
 946	mutex_unlock(&bridge_mutex);
 947}
 948
 949/**
 950 * acpiphp_enable_slot - power on slot
 951 * @slot: ACPI PHP slot
 952 */
 953int acpiphp_enable_slot(struct acpiphp_slot *slot)
 954{
 955	pci_lock_rescan_remove();
 956
 957	if (slot->flags & SLOT_IS_GOING_AWAY)
 
 958		return -ENODEV;
 
 959
 960	/* configure all functions */
 961	if (!(slot->flags & SLOT_ENABLED))
 962		enable_slot(slot);
 963
 964	pci_unlock_rescan_remove();
 965	return 0;
 966}
 967
 968/**
 969 * acpiphp_disable_and_eject_slot - power off and eject slot
 970 * @slot: ACPI PHP slot
 971 */
 972static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
 973{
 974	struct acpiphp_func *func;
 975
 976	if (slot->flags & SLOT_IS_GOING_AWAY)
 977		return -ENODEV;
 978
 979	/* unconfigure all functions */
 980	disable_slot(slot);
 981
 982	list_for_each_entry(func, &slot->funcs, sibling)
 983		if (func->flags & FUNC_HAS_EJ0) {
 984			acpi_handle handle = func_to_handle(func);
 985
 986			if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
 987				acpi_handle_err(handle, "_EJ0 failed\n");
 988
 989			break;
 990		}
 991
 992	return 0;
 993}
 994
 995int acpiphp_disable_slot(struct acpiphp_slot *slot)
 996{
 997	int ret;
 998
 999	/*
1000	 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1001	 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1002	 */
1003	acpi_scan_lock_acquire();
1004	pci_lock_rescan_remove();
1005	ret = acpiphp_disable_and_eject_slot(slot);
1006	pci_unlock_rescan_remove();
1007	acpi_scan_lock_release();
1008	return ret;
1009}
1010
1011/*
1012 * slot enabled:  1
1013 * slot disabled: 0
1014 */
1015u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1016{
1017	return (slot->flags & SLOT_ENABLED);
1018}
1019
1020/*
1021 * latch   open:  1
1022 * latch closed:  0
1023 */
1024u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1025{
1026	return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1027}
1028
1029/*
1030 * adapter presence : 1
1031 *          absence : 0
1032 */
1033u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1034{
1035	return !!get_slot_status(slot);
1036}
v4.6
   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/module.h>
  45
  46#include <linux/kernel.h>
  47#include <linux/pci.h>
  48#include <linux/pci_hotplug.h>
  49#include <linux/pci-acpi.h>
  50#include <linux/pm_runtime.h>
  51#include <linux/mutex.h>
  52#include <linux/slab.h>
  53#include <linux/acpi.h>
  54
  55#include "../pci.h"
  56#include "acpiphp.h"
  57
  58static LIST_HEAD(bridge_list);
  59static DEFINE_MUTEX(bridge_mutex);
  60
  61static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
  62static void acpiphp_post_dock_fixup(struct acpi_device *adev);
  63static void acpiphp_sanitize_bus(struct pci_bus *bus);
 
  64static void hotplug_event(u32 type, struct acpiphp_context *context);
  65static void free_bridge(struct kref *kref);
  66
  67/**
  68 * acpiphp_init_context - Create hotplug context and grab a reference to it.
  69 * @adev: ACPI device object to create the context for.
  70 *
  71 * Call under acpi_hp_context_lock.
  72 */
  73static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
  74{
  75	struct acpiphp_context *context;
  76
  77	context = kzalloc(sizeof(*context), GFP_KERNEL);
  78	if (!context)
  79		return NULL;
  80
  81	context->refcount = 1;
  82	context->hp.notify = acpiphp_hotplug_notify;
  83	context->hp.fixup = acpiphp_post_dock_fixup;
  84	acpi_set_hp_context(adev, &context->hp);
  85	return context;
  86}
  87
  88/**
  89 * acpiphp_get_context - Get hotplug context and grab a reference to it.
  90 * @adev: ACPI device object to get the context for.
  91 *
  92 * Call under acpi_hp_context_lock.
  93 */
  94static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
  95{
  96	struct acpiphp_context *context;
  97
  98	if (!adev->hp)
  99		return NULL;
 100
 101	context = to_acpiphp_context(adev->hp);
 102	context->refcount++;
 103	return context;
 104}
 105
 106/**
 107 * acpiphp_put_context - Drop a reference to ACPI hotplug context.
 108 * @context: ACPI hotplug context to drop a reference to.
 109 *
 110 * The context object is removed if there are no more references to it.
 111 *
 112 * Call under acpi_hp_context_lock.
 113 */
 114static void acpiphp_put_context(struct acpiphp_context *context)
 115{
 116	if (--context->refcount)
 117		return;
 118
 119	WARN_ON(context->bridge);
 120	context->hp.self->hp = NULL;
 121	kfree(context);
 122}
 123
 124static inline void get_bridge(struct acpiphp_bridge *bridge)
 125{
 126	kref_get(&bridge->ref);
 127}
 128
 129static inline void put_bridge(struct acpiphp_bridge *bridge)
 130{
 131	kref_put(&bridge->ref, free_bridge);
 132}
 133
 134static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
 135{
 136	struct acpiphp_context *context;
 137
 138	acpi_lock_hp_context();
 139	context = acpiphp_get_context(adev);
 140	if (!context || context->func.parent->is_going_away) {
 141		acpi_unlock_hp_context();
 142		return NULL;
 143	}
 144	get_bridge(context->func.parent);
 145	acpiphp_put_context(context);
 146	acpi_unlock_hp_context();
 147	return context;
 148}
 149
 150static void acpiphp_let_context_go(struct acpiphp_context *context)
 151{
 152	put_bridge(context->func.parent);
 153}
 154
 155static void free_bridge(struct kref *kref)
 156{
 157	struct acpiphp_context *context;
 158	struct acpiphp_bridge *bridge;
 159	struct acpiphp_slot *slot, *next;
 160	struct acpiphp_func *func, *tmp;
 161
 162	acpi_lock_hp_context();
 163
 164	bridge = container_of(kref, struct acpiphp_bridge, ref);
 165
 166	list_for_each_entry_safe(slot, next, &bridge->slots, node) {
 167		list_for_each_entry_safe(func, tmp, &slot->funcs, sibling)
 168			acpiphp_put_context(func_to_context(func));
 169
 170		kfree(slot);
 171	}
 172
 173	context = bridge->context;
 174	/* Root bridges will not have hotplug context. */
 175	if (context) {
 176		/* Release the reference taken by acpiphp_enumerate_slots(). */
 177		put_bridge(context->func.parent);
 178		context->bridge = NULL;
 179		acpiphp_put_context(context);
 180	}
 181
 182	put_device(&bridge->pci_bus->dev);
 183	pci_dev_put(bridge->pci_dev);
 184	kfree(bridge);
 185
 186	acpi_unlock_hp_context();
 187}
 188
 189/**
 190 * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
 191 * @adev: ACPI device object corresponding to a PCI device.
 192 *
 193 * TBD - figure out a way to only call fixups for systems that require them.
 194 */
 195static void acpiphp_post_dock_fixup(struct acpi_device *adev)
 196{
 197	struct acpiphp_context *context = acpiphp_grab_context(adev);
 198	struct pci_bus *bus;
 199	u32 buses;
 200
 201	if (!context)
 202		return;
 203
 204	bus = context->func.slot->bus;
 205	if (!bus->self)
 206		goto out;
 207
 208	/* fixup bad _DCK function that rewrites
 209	 * secondary bridge on slot
 210	 */
 211	pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
 212
 213	if (((buses >> 8) & 0xff) != bus->busn_res.start) {
 214		buses = (buses & 0xff000000)
 215			| ((unsigned int)(bus->primary)     <<  0)
 216			| ((unsigned int)(bus->busn_res.start)   <<  8)
 217			| ((unsigned int)(bus->busn_res.end) << 16);
 218		pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
 219	}
 220
 221 out:
 222	acpiphp_let_context_go(context);
 223}
 224
 225/* Check whether the PCI device is managed by native PCIe hotplug driver */
 226static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
 227{
 228	u32 reg32;
 229	acpi_handle tmp;
 230	struct acpi_pci_root *root;
 231
 232	/* Check whether the PCIe port supports native PCIe hotplug */
 233	if (pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32))
 234		return false;
 235	if (!(reg32 & PCI_EXP_SLTCAP_HPC))
 236		return false;
 237
 238	/*
 239	 * Check whether native PCIe hotplug has been enabled for
 240	 * this PCIe hierarchy.
 241	 */
 242	tmp = acpi_find_root_bridge_handle(pdev);
 243	if (!tmp)
 244		return false;
 245	root = acpi_pci_find_root(tmp);
 246	if (!root)
 247		return false;
 248	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
 249		return false;
 250
 251	return true;
 252}
 253
 254/**
 255 * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
 256 * @handle: ACPI handle of the object to add a context to.
 257 * @lvl: Not used.
 258 * @data: The object's parent ACPIPHP bridge.
 259 * @rv: Not used.
 260 */
 261static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
 262				       void **rv)
 263{
 264	struct acpiphp_bridge *bridge = data;
 265	struct acpiphp_context *context;
 266	struct acpi_device *adev;
 267	struct acpiphp_slot *slot;
 268	struct acpiphp_func *newfunc;
 269	acpi_status status = AE_OK;
 270	unsigned long long adr;
 271	int device, function;
 272	struct pci_bus *pbus = bridge->pci_bus;
 273	struct pci_dev *pdev = bridge->pci_dev;
 274	u32 val;
 275
 276	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
 277	if (ACPI_FAILURE(status)) {
 278		if (status != AE_NOT_FOUND)
 279			acpi_handle_warn(handle,
 280				"can't evaluate _ADR (%#x)\n", status);
 281		return AE_OK;
 282	}
 283	if (acpi_bus_get_device(handle, &adev))
 284		return AE_OK;
 285
 286	device = (adr >> 16) & 0xffff;
 287	function = adr & 0xffff;
 288
 289	acpi_lock_hp_context();
 290	context = acpiphp_init_context(adev);
 291	if (!context) {
 292		acpi_unlock_hp_context();
 293		acpi_handle_err(handle, "No hotplug context\n");
 294		return AE_NOT_EXIST;
 295	}
 296	newfunc = &context->func;
 297	newfunc->function = function;
 298	newfunc->parent = bridge;
 299	acpi_unlock_hp_context();
 300
 301	/*
 302	 * If this is a dock device, its _EJ0 should be executed by the dock
 303	 * notify handler after calling _DCK.
 304	 */
 305	if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
 306		newfunc->flags = FUNC_HAS_EJ0;
 307
 308	if (acpi_has_method(handle, "_STA"))
 309		newfunc->flags |= FUNC_HAS_STA;
 310
 311	/* search for objects that share the same slot */
 312	list_for_each_entry(slot, &bridge->slots, node)
 313		if (slot->device == device)
 314			goto slot_found;
 315
 316	slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
 317	if (!slot) {
 318		acpi_lock_hp_context();
 319		acpiphp_put_context(context);
 320		acpi_unlock_hp_context();
 321		return AE_NO_MEMORY;
 322	}
 323
 324	slot->bus = bridge->pci_bus;
 325	slot->device = device;
 326	INIT_LIST_HEAD(&slot->funcs);
 327
 328	list_add_tail(&slot->node, &bridge->slots);
 329
 330	/*
 331	 * Expose slots to user space for functions that have _EJ0 or _RMV or
 332	 * are located in dock stations.  Do not expose them for devices handled
 333	 * by the native PCIe hotplug (PCIeHP), becuase that code is supposed to
 334	 * expose slots to user space in those cases.
 335	 */
 336	if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
 337	    && !(pdev && device_is_managed_by_native_pciehp(pdev))) {
 338		unsigned long long sun;
 339		int retval;
 340
 341		bridge->nr_slots++;
 342		status = acpi_evaluate_integer(handle, "_SUN", NULL, &sun);
 343		if (ACPI_FAILURE(status))
 344			sun = bridge->nr_slots;
 345
 346		pr_debug("found ACPI PCI Hotplug slot %llu at PCI %04x:%02x:%02x\n",
 347		    sun, pci_domain_nr(pbus), pbus->number, device);
 348
 349		retval = acpiphp_register_hotplug_slot(slot, sun);
 350		if (retval) {
 351			slot->slot = NULL;
 352			bridge->nr_slots--;
 353			if (retval == -EBUSY)
 354				pr_warn("Slot %llu already registered by another hotplug driver\n", sun);
 
 355			else
 356				pr_warn("acpiphp_register_hotplug_slot failed (err code = 0x%x)\n", retval);
 
 357		}
 358		/* Even if the slot registration fails, we can still use it. */
 359	}
 360
 361 slot_found:
 362	newfunc->slot = slot;
 363	list_add_tail(&newfunc->sibling, &slot->funcs);
 364
 365	if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
 366				       &val, 60*1000))
 367		slot->flags |= SLOT_ENABLED;
 368
 369	return AE_OK;
 370}
 371
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 372static void cleanup_bridge(struct acpiphp_bridge *bridge)
 373{
 374	struct acpiphp_slot *slot;
 375	struct acpiphp_func *func;
 376
 377	list_for_each_entry(slot, &bridge->slots, node) {
 378		list_for_each_entry(func, &slot->funcs, sibling) {
 379			struct acpi_device *adev = func_to_acpi_device(func);
 380
 381			acpi_lock_hp_context();
 382			adev->hp->notify = NULL;
 383			adev->hp->fixup = NULL;
 384			acpi_unlock_hp_context();
 385		}
 386		slot->flags |= SLOT_IS_GOING_AWAY;
 387		if (slot->slot)
 388			acpiphp_unregister_hotplug_slot(slot);
 389	}
 390
 391	mutex_lock(&bridge_mutex);
 392	list_del(&bridge->list);
 393	mutex_unlock(&bridge_mutex);
 394
 395	acpi_lock_hp_context();
 396	bridge->is_going_away = true;
 397	acpi_unlock_hp_context();
 398}
 399
 400/**
 401 * acpiphp_max_busnr - return the highest reserved bus number under the given bus.
 402 * @bus: bus to start search with
 403 */
 404static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
 405{
 406	struct pci_bus *tmp;
 407	unsigned char max, n;
 408
 409	/*
 410	 * pci_bus_max_busnr will return the highest
 411	 * reserved busnr for all these children.
 412	 * that is equivalent to the bus->subordinate
 413	 * value.  We don't want to use the parent's
 414	 * bus->subordinate value because it could have
 415	 * padding in it.
 416	 */
 417	max = bus->busn_res.start;
 418
 419	list_for_each_entry(tmp, &bus->children, node) {
 420		n = pci_bus_max_busnr(tmp);
 421		if (n > max)
 422			max = n;
 423	}
 424	return max;
 425}
 426
 427static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
 428{
 429	struct acpiphp_func *func;
 430	union acpi_object params[2];
 431	struct acpi_object_list arg_list;
 432
 433	list_for_each_entry(func, &slot->funcs, sibling) {
 434		arg_list.count = 2;
 435		arg_list.pointer = params;
 436		params[0].type = ACPI_TYPE_INTEGER;
 437		params[0].integer.value = ACPI_ADR_SPACE_PCI_CONFIG;
 438		params[1].type = ACPI_TYPE_INTEGER;
 439		params[1].integer.value = 1;
 440		/* _REG is optional, we don't care about if there is failure */
 441		acpi_evaluate_object(func_to_handle(func), "_REG", &arg_list,
 442				     NULL);
 443	}
 444}
 445
 446static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
 447{
 448	struct acpiphp_func *func;
 449
 450	/* quirk, or pcie could set it already */
 451	if (dev->is_hotplug_bridge)
 452		return;
 453
 454	list_for_each_entry(func, &slot->funcs, sibling) {
 455		if (PCI_FUNC(dev->devfn) == func->function) {
 456			dev->is_hotplug_bridge = 1;
 457			break;
 458		}
 459	}
 460}
 461
 462static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
 463{
 464	struct acpiphp_func *func;
 465
 466	list_for_each_entry(func, &slot->funcs, sibling) {
 467		struct acpi_device *adev = func_to_acpi_device(func);
 468
 469		acpi_bus_scan(adev->handle);
 470		if (acpi_device_enumerated(adev))
 471			acpi_device_set_power(adev, ACPI_STATE_D0);
 472	}
 473	return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
 474}
 475
 476/**
 477 * enable_slot - enable, configure a slot
 478 * @slot: slot to be enabled
 479 *
 480 * This function should be called per *physical slot*,
 481 * not per each slot object in ACPI namespace.
 482 */
 483static void enable_slot(struct acpiphp_slot *slot)
 484{
 485	struct pci_dev *dev;
 486	struct pci_bus *bus = slot->bus;
 487	struct acpiphp_func *func;
 488	int max, pass;
 489	LIST_HEAD(add_list);
 490
 491	acpiphp_rescan_slot(slot);
 492	max = acpiphp_max_busnr(bus);
 493	for (pass = 0; pass < 2; pass++) {
 494		list_for_each_entry(dev, &bus->devices, bus_list) {
 495			if (PCI_SLOT(dev->devfn) != slot->device)
 496				continue;
 497
 498			if (pci_is_bridge(dev)) {
 
 499				max = pci_scan_bridge(bus, dev, max, pass);
 500				if (pass && dev->subordinate) {
 501					check_hotplug_bridge(slot, dev);
 502					pcibios_resource_survey_bus(dev->subordinate);
 503					__pci_bus_size_bridges(dev->subordinate,
 504							       &add_list);
 505				}
 506			}
 507		}
 508	}
 509	__pci_bus_assign_resources(bus, &add_list, NULL);
 510
 511	acpiphp_sanitize_bus(bus);
 512	pcie_bus_configure_settings(bus);
 513	acpiphp_set_acpi_region(slot);
 514
 515	list_for_each_entry(dev, &bus->devices, bus_list) {
 516		/* Assume that newly added devices are powered on already. */
 517		if (!dev->is_added)
 518			dev->current_state = PCI_D0;
 519	}
 520
 521	pci_bus_add_devices(bus);
 522
 523	slot->flags |= SLOT_ENABLED;
 524	list_for_each_entry(func, &slot->funcs, sibling) {
 525		dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
 526						  func->function));
 527		if (!dev) {
 528			/* Do not set SLOT_ENABLED flag if some funcs
 529			   are not added. */
 530			slot->flags &= (~SLOT_ENABLED);
 531			continue;
 532		}
 533	}
 534}
 535
 536/**
 537 * disable_slot - disable a slot
 538 * @slot: ACPI PHP slot
 539 */
 540static void disable_slot(struct acpiphp_slot *slot)
 541{
 542	struct pci_bus *bus = slot->bus;
 543	struct pci_dev *dev, *prev;
 544	struct acpiphp_func *func;
 545
 546	/*
 547	 * enable_slot() enumerates all functions in this device via
 548	 * pci_scan_slot(), whether they have associated ACPI hotplug
 549	 * methods (_EJ0, etc.) or not.  Therefore, we remove all functions
 550	 * here.
 551	 */
 552	list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list)
 553		if (PCI_SLOT(dev->devfn) == slot->device)
 554			pci_stop_and_remove_bus_device(dev);
 555
 556	list_for_each_entry(func, &slot->funcs, sibling)
 557		acpi_bus_trim(func_to_acpi_device(func));
 558
 559	slot->flags &= (~SLOT_ENABLED);
 560}
 561
 
 
 
 
 
 562static bool slot_no_hotplug(struct acpiphp_slot *slot)
 563{
 564	struct pci_bus *bus = slot->bus;
 565	struct pci_dev *dev;
 566
 567	list_for_each_entry(dev, &bus->devices, bus_list) {
 568		if (PCI_SLOT(dev->devfn) == slot->device && dev->ignore_hotplug)
 569			return true;
 570	}
 571	return false;
 572}
 573
 574/**
 575 * get_slot_status - get ACPI slot status
 576 * @slot: ACPI PHP slot
 577 *
 578 * If a slot has _STA for each function and if any one of them
 579 * returned non-zero status, return it.
 580 *
 581 * If a slot doesn't have _STA and if any one of its functions'
 582 * configuration space is configured, return 0x0f as a _STA.
 583 *
 584 * Otherwise return 0.
 585 */
 586static unsigned int get_slot_status(struct acpiphp_slot *slot)
 587{
 588	unsigned long long sta = 0;
 589	struct acpiphp_func *func;
 590
 591	list_for_each_entry(func, &slot->funcs, sibling) {
 592		if (func->flags & FUNC_HAS_STA) {
 593			acpi_status status;
 594
 595			status = acpi_evaluate_integer(func_to_handle(func),
 596						       "_STA", NULL, &sta);
 597			if (ACPI_SUCCESS(status) && sta)
 598				break;
 599		} else {
 600			u32 dvid;
 601
 602			pci_bus_read_config_dword(slot->bus,
 603						  PCI_DEVFN(slot->device,
 604							    func->function),
 605						  PCI_VENDOR_ID, &dvid);
 606			if (dvid != 0xffffffff) {
 607				sta = ACPI_STA_ALL;
 608				break;
 609			}
 610		}
 611	}
 612
 613	return (unsigned int)sta;
 614}
 615
 616static inline bool device_status_valid(unsigned int sta)
 617{
 618	/*
 619	 * ACPI spec says that _STA may return bit 0 clear with bit 3 set
 620	 * if the device is valid but does not require a device driver to be
 621	 * loaded (Section 6.3.7 of ACPI 5.0A).
 622	 */
 623	unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
 624	return (sta & mask) == mask;
 625}
 626
 627/**
 628 * trim_stale_devices - remove PCI devices that are not responding.
 629 * @dev: PCI device to start walking the hierarchy from.
 630 */
 631static void trim_stale_devices(struct pci_dev *dev)
 632{
 633	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
 634	struct pci_bus *bus = dev->subordinate;
 635	bool alive = dev->ignore_hotplug;
 636
 637	if (adev) {
 638		acpi_status status;
 639		unsigned long long sta;
 640
 641		status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
 642		alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta));
 
 643	}
 644	if (!alive)
 645		alive = pci_device_is_present(dev);
 646
 647	if (!alive) {
 648		pci_stop_and_remove_bus_device(dev);
 649		if (adev)
 650			acpi_bus_trim(adev);
 651	} else if (bus) {
 652		struct pci_dev *child, *tmp;
 653
 654		/* The device is a bridge. so check the bus below it. */
 655		pm_runtime_get_sync(&dev->dev);
 656		list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
 657			trim_stale_devices(child);
 658
 659		pm_runtime_put(&dev->dev);
 660	}
 661}
 662
 663/**
 664 * acpiphp_check_bridge - re-enumerate devices
 665 * @bridge: where to begin re-enumeration
 666 *
 667 * Iterate over all slots under this bridge and make sure that if a
 668 * card is present they are enabled, and if not they are disabled.
 669 */
 670static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
 671{
 672	struct acpiphp_slot *slot;
 673
 674	/* Bail out if the bridge is going away. */
 675	if (bridge->is_going_away)
 676		return;
 677
 678	list_for_each_entry(slot, &bridge->slots, node) {
 679		struct pci_bus *bus = slot->bus;
 680		struct pci_dev *dev, *tmp;
 681
 682		if (slot_no_hotplug(slot)) {
 683			; /* do nothing */
 684		} else if (device_status_valid(get_slot_status(slot))) {
 685			/* remove stale devices if any */
 686			list_for_each_entry_safe_reverse(dev, tmp,
 687							 &bus->devices, bus_list)
 688				if (PCI_SLOT(dev->devfn) == slot->device)
 689					trim_stale_devices(dev);
 690
 691			/* configure all functions */
 692			enable_slot(slot);
 693		} else {
 694			disable_slot(slot);
 695		}
 696	}
 697}
 698
 
 
 
 
 
 
 
 
 699/*
 700 * Remove devices for which we could not assign resources, call
 701 * arch specific code to fix-up the bus
 702 */
 703static void acpiphp_sanitize_bus(struct pci_bus *bus)
 704{
 705	struct pci_dev *dev, *tmp;
 706	int i;
 707	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
 708
 709	list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
 710		for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
 711			struct resource *res = &dev->resource[i];
 712			if ((res->flags & type_mask) && !res->start &&
 713					res->end) {
 714				/* Could not assign a required resources
 715				 * for this device, remove it */
 716				pci_stop_and_remove_bus_device(dev);
 717				break;
 718			}
 719		}
 720	}
 721}
 722
 723/*
 724 * ACPI event handlers
 725 */
 726
 727void acpiphp_check_host_bridge(struct acpi_device *adev)
 728{
 729	struct acpiphp_bridge *bridge = NULL;
 730
 731	acpi_lock_hp_context();
 732	if (adev->hp) {
 733		bridge = to_acpiphp_root_context(adev->hp)->root_bridge;
 734		if (bridge)
 735			get_bridge(bridge);
 736	}
 737	acpi_unlock_hp_context();
 738	if (bridge) {
 739		pci_lock_rescan_remove();
 740
 741		acpiphp_check_bridge(bridge);
 742
 743		pci_unlock_rescan_remove();
 744		put_bridge(bridge);
 745	}
 746}
 747
 748static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
 749
 750static void hotplug_event(u32 type, struct acpiphp_context *context)
 751{
 752	acpi_handle handle = context->hp.self->handle;
 753	struct acpiphp_func *func = &context->func;
 754	struct acpiphp_slot *slot = func->slot;
 755	struct acpiphp_bridge *bridge;
 756
 757	acpi_lock_hp_context();
 758	bridge = context->bridge;
 759	if (bridge)
 760		get_bridge(bridge);
 761
 762	acpi_unlock_hp_context();
 763
 764	pci_lock_rescan_remove();
 765
 766	switch (type) {
 767	case ACPI_NOTIFY_BUS_CHECK:
 768		/* bus re-enumerate */
 769		acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
 770		if (bridge)
 771			acpiphp_check_bridge(bridge);
 772		else if (!(slot->flags & SLOT_IS_GOING_AWAY))
 773			enable_slot(slot);
 774
 775		break;
 776
 777	case ACPI_NOTIFY_DEVICE_CHECK:
 778		/* device check */
 779		acpi_handle_debug(handle, "Device check in %s()\n", __func__);
 780		if (bridge) {
 781			acpiphp_check_bridge(bridge);
 782		} else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
 783			/*
 784			 * Check if anything has changed in the slot and rescan
 785			 * from the parent if that's the case.
 786			 */
 787			if (acpiphp_rescan_slot(slot))
 788				acpiphp_check_bridge(func->parent);
 789		}
 790		break;
 791
 792	case ACPI_NOTIFY_EJECT_REQUEST:
 793		/* request device eject */
 794		acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
 795		acpiphp_disable_and_eject_slot(slot);
 796		break;
 797	}
 798
 799	pci_unlock_rescan_remove();
 800	if (bridge)
 801		put_bridge(bridge);
 802}
 803
 804static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
 805{
 806	struct acpiphp_context *context;
 807
 808	context = acpiphp_grab_context(adev);
 809	if (!context)
 810		return -ENODATA;
 811
 812	hotplug_event(type, context);
 813	acpiphp_let_context_go(context);
 814	return 0;
 815}
 816
 817/**
 818 * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
 819 * @bus: PCI bus to enumerate the slots for.
 820 *
 821 * A "slot" is an object associated with a PCI device number.  All functions
 822 * (PCI devices) with the same bus and device number belong to the same slot.
 823 */
 824void acpiphp_enumerate_slots(struct pci_bus *bus)
 825{
 826	struct acpiphp_bridge *bridge;
 827	struct acpi_device *adev;
 828	acpi_handle handle;
 829	acpi_status status;
 830
 831	if (acpiphp_disabled)
 832		return;
 833
 834	adev = ACPI_COMPANION(bus->bridge);
 835	if (!adev)
 836		return;
 837
 838	handle = adev->handle;
 839	bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
 840	if (!bridge) {
 841		acpi_handle_err(handle, "No memory for bridge object\n");
 842		return;
 843	}
 844
 845	INIT_LIST_HEAD(&bridge->slots);
 846	kref_init(&bridge->ref);
 847	bridge->pci_dev = pci_dev_get(bus->self);
 848	bridge->pci_bus = bus;
 849
 850	/*
 851	 * Grab a ref to the subordinate PCI bus in case the bus is
 852	 * removed via PCI core logical hotplug. The ref pins the bus
 853	 * (which we access during module unload).
 854	 */
 855	get_device(&bus->dev);
 856
 857	acpi_lock_hp_context();
 858	if (pci_is_root_bus(bridge->pci_bus)) {
 859		struct acpiphp_root_context *root_context;
 860
 861		root_context = kzalloc(sizeof(*root_context), GFP_KERNEL);
 862		if (!root_context)
 863			goto err;
 864
 865		root_context->root_bridge = bridge;
 866		acpi_set_hp_context(adev, &root_context->hp);
 867	} else {
 868		struct acpiphp_context *context;
 869
 870		/*
 871		 * This bridge should have been registered as a hotplug function
 872		 * under its parent, so the context should be there, unless the
 873		 * parent is going to be handled by pciehp, in which case this
 874		 * bridge is not interesting to us either.
 875		 */
 
 876		context = acpiphp_get_context(adev);
 877		if (!context)
 878			goto err;
 879
 
 
 
 
 880		bridge->context = context;
 881		context->bridge = bridge;
 882		/* Get a reference to the parent bridge. */
 883		get_bridge(context->func.parent);
 
 884	}
 885	acpi_unlock_hp_context();
 886
 887	/* Must be added to the list prior to calling acpiphp_add_context(). */
 888	mutex_lock(&bridge_mutex);
 889	list_add(&bridge->list, &bridge_list);
 890	mutex_unlock(&bridge_mutex);
 891
 892	/* register all slot objects under this bridge */
 893	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
 894				     acpiphp_add_context, NULL, bridge, NULL);
 895	if (ACPI_FAILURE(status)) {
 896		acpi_handle_err(handle, "failed to register slots\n");
 897		cleanup_bridge(bridge);
 898		put_bridge(bridge);
 899	}
 900	return;
 901
 902 err:
 903	acpi_unlock_hp_context();
 904	put_device(&bus->dev);
 905	pci_dev_put(bridge->pci_dev);
 906	kfree(bridge);
 907}
 908
 909static void acpiphp_drop_bridge(struct acpiphp_bridge *bridge)
 910{
 911	if (pci_is_root_bus(bridge->pci_bus)) {
 912		struct acpiphp_root_context *root_context;
 913		struct acpi_device *adev;
 914
 915		acpi_lock_hp_context();
 916		adev = ACPI_COMPANION(bridge->pci_bus->bridge);
 917		root_context = to_acpiphp_root_context(adev->hp);
 918		adev->hp = NULL;
 919		acpi_unlock_hp_context();
 920		kfree(root_context);
 921	}
 922	cleanup_bridge(bridge);
 923	put_bridge(bridge);
 924}
 925
 926/**
 927 * acpiphp_remove_slots - Remove slot objects associated with a given bus.
 928 * @bus: PCI bus to remove the slot objects for.
 929 */
 930void acpiphp_remove_slots(struct pci_bus *bus)
 931{
 932	struct acpiphp_bridge *bridge;
 933
 934	if (acpiphp_disabled)
 935		return;
 936
 937	mutex_lock(&bridge_mutex);
 938	list_for_each_entry(bridge, &bridge_list, list)
 939		if (bridge->pci_bus == bus) {
 940			mutex_unlock(&bridge_mutex);
 941			acpiphp_drop_bridge(bridge);
 
 942			return;
 943		}
 944
 945	mutex_unlock(&bridge_mutex);
 946}
 947
 948/**
 949 * acpiphp_enable_slot - power on slot
 950 * @slot: ACPI PHP slot
 951 */
 952int acpiphp_enable_slot(struct acpiphp_slot *slot)
 953{
 954	pci_lock_rescan_remove();
 955
 956	if (slot->flags & SLOT_IS_GOING_AWAY) {
 957		pci_unlock_rescan_remove();
 958		return -ENODEV;
 959	}
 960
 961	/* configure all functions */
 962	if (!(slot->flags & SLOT_ENABLED))
 963		enable_slot(slot);
 964
 965	pci_unlock_rescan_remove();
 966	return 0;
 967}
 968
 969/**
 970 * acpiphp_disable_and_eject_slot - power off and eject slot
 971 * @slot: ACPI PHP slot
 972 */
 973static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
 974{
 975	struct acpiphp_func *func;
 976
 977	if (slot->flags & SLOT_IS_GOING_AWAY)
 978		return -ENODEV;
 979
 980	/* unconfigure all functions */
 981	disable_slot(slot);
 982
 983	list_for_each_entry(func, &slot->funcs, sibling)
 984		if (func->flags & FUNC_HAS_EJ0) {
 985			acpi_handle handle = func_to_handle(func);
 986
 987			if (ACPI_FAILURE(acpi_evaluate_ej0(handle)))
 988				acpi_handle_err(handle, "_EJ0 failed\n");
 989
 990			break;
 991		}
 992
 993	return 0;
 994}
 995
 996int acpiphp_disable_slot(struct acpiphp_slot *slot)
 997{
 998	int ret;
 999
1000	/*
1001	 * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
1002	 * acpiphp_disable_and_eject_slot() will be synchronized properly.
1003	 */
1004	acpi_scan_lock_acquire();
1005	pci_lock_rescan_remove();
1006	ret = acpiphp_disable_and_eject_slot(slot);
1007	pci_unlock_rescan_remove();
1008	acpi_scan_lock_release();
1009	return ret;
1010}
1011
1012/*
1013 * slot enabled:  1
1014 * slot disabled: 0
1015 */
1016u8 acpiphp_get_power_status(struct acpiphp_slot *slot)
1017{
1018	return (slot->flags & SLOT_ENABLED);
1019}
1020
1021/*
1022 * latch   open:  1
1023 * latch closed:  0
1024 */
1025u8 acpiphp_get_latch_status(struct acpiphp_slot *slot)
1026{
1027	return !(get_slot_status(slot) & ACPI_STA_DEVICE_UI);
1028}
1029
1030/*
1031 * adapter presence : 1
1032 *          absence : 0
1033 */
1034u8 acpiphp_get_adapter_status(struct acpiphp_slot *slot)
1035{
1036	return !!get_slot_status(slot);
1037}