1/*
   2 * scan.c - support for transforming the ACPI namespace into individual objects
   3 */
   4
   5#include <linux/module.h>
   6#include <linux/init.h>
   7#include <linux/slab.h>
   8#include <linux/kernel.h>
   9#include <linux/acpi.h>
  10#include <linux/acpi_iort.h>
  11#include <linux/signal.h>
  12#include <linux/kthread.h>
  13#include <linux/dmi.h>
  14#include <linux/nls.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/platform_data/x86/apple.h>
  17
  18#include <asm/pgtable.h>
  19
  20#include "internal.h"
  21
  22#define _COMPONENT		ACPI_BUS_COMPONENT
  23ACPI_MODULE_NAME("scan");
  24extern struct acpi_device *acpi_root;
  25
  26#define ACPI_BUS_CLASS			"system_bus"
  27#define ACPI_BUS_HID			"LNXSYBUS"
  28#define ACPI_BUS_DEVICE_NAME		"System Bus"
  29
  30#define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  31
  32#define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
  33
  34static const char *dummy_hid = "device";
  35
  36static LIST_HEAD(acpi_dep_list);
  37static DEFINE_MUTEX(acpi_dep_list_lock);
  38LIST_HEAD(acpi_bus_id_list);
  39static DEFINE_MUTEX(acpi_scan_lock);
  40static LIST_HEAD(acpi_scan_handlers_list);
  41DEFINE_MUTEX(acpi_device_lock);
  42LIST_HEAD(acpi_wakeup_device_list);
  43static DEFINE_MUTEX(acpi_hp_context_lock);
  44
  45/*
  46 * The UART device described by the SPCR table is the only object which needs
  47 * special-casing. Everything else is covered by ACPI namespace paths in STAO
  48 * table.
  49 */
  50static u64 spcr_uart_addr;
  51
  52struct acpi_dep_data {
  53	struct list_head node;
  54	acpi_handle master;
  55	acpi_handle slave;
  56};
  57
  58void acpi_scan_lock_acquire(void)
  59{
  60	mutex_lock(&acpi_scan_lock);
  61}
  62EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  63
  64void acpi_scan_lock_release(void)
  65{
  66	mutex_unlock(&acpi_scan_lock);
  67}
  68EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  69
  70void acpi_lock_hp_context(void)
  71{
  72	mutex_lock(&acpi_hp_context_lock);
  73}
  74
  75void acpi_unlock_hp_context(void)
  76{
  77	mutex_unlock(&acpi_hp_context_lock);
  78}
  79
  80void acpi_initialize_hp_context(struct acpi_device *adev,
  81				struct acpi_hotplug_context *hp,
  82				int (*notify)(struct acpi_device *, u32),
  83				void (*uevent)(struct acpi_device *, u32))
  84{
  85	acpi_lock_hp_context();
  86	hp->notify = notify;
  87	hp->uevent = uevent;
  88	acpi_set_hp_context(adev, hp);
  89	acpi_unlock_hp_context();
  90}
  91EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  92
  93int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  94{
  95	if (!handler)
  96		return -EINVAL;
  97
  98	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  99	return 0;
 100}
 101
 102int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 103				       const char *hotplug_profile_name)
 104{
 105	int error;
 106
 107	error = acpi_scan_add_handler(handler);
 108	if (error)
 109		return error;
 110
 111	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 112	return 0;
 113}
 114
 115bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 116{
 117	struct acpi_device_physical_node *pn;
 118	bool offline = true;
 119	char *envp[] = { "EVENT=offline", NULL };
 120
 121	/*
 122	 * acpi_container_offline() calls this for all of the container's
 123	 * children under the container's physical_node_lock lock.
 124	 */
 125	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 126
 127	list_for_each_entry(pn, &adev->physical_node_list, node)
 128		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 129			if (uevent)
 130				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
 131
 132			offline = false;
 133			break;
 134		}
 135
 136	mutex_unlock(&adev->physical_node_lock);
 137	return offline;
 138}
 139
 140static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 141				    void **ret_p)
 142{
 143	struct acpi_device *device = NULL;
 144	struct acpi_device_physical_node *pn;
 145	bool second_pass = (bool)data;
 146	acpi_status status = AE_OK;
 147
 148	if (acpi_bus_get_device(handle, &device))
 149		return AE_OK;
 150
 151	if (device->handler && !device->handler->hotplug.enabled) {
 152		*ret_p = &device->dev;
 153		return AE_SUPPORT;
 154	}
 155
 156	mutex_lock(&device->physical_node_lock);
 157
 158	list_for_each_entry(pn, &device->physical_node_list, node) {
 159		int ret;
 160
 161		if (second_pass) {
 162			/* Skip devices offlined by the first pass. */
 163			if (pn->put_online)
 164				continue;
 165		} else {
 166			pn->put_online = false;
 167		}
 168		ret = device_offline(pn->dev);
 169		if (ret >= 0) {
 170			pn->put_online = !ret;
 171		} else {
 172			*ret_p = pn->dev;
 173			if (second_pass) {
 174				status = AE_ERROR;
 175				break;
 176			}
 177		}
 178	}
 179
 180	mutex_unlock(&device->physical_node_lock);
 181
 182	return status;
 183}
 184
 185static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 186				   void **ret_p)
 187{
 188	struct acpi_device *device = NULL;
 189	struct acpi_device_physical_node *pn;
 190
 191	if (acpi_bus_get_device(handle, &device))
 192		return AE_OK;
 193
 194	mutex_lock(&device->physical_node_lock);
 195
 196	list_for_each_entry(pn, &device->physical_node_list, node)
 197		if (pn->put_online) {
 198			device_online(pn->dev);
 199			pn->put_online = false;
 200		}
 201
 202	mutex_unlock(&device->physical_node_lock);
 203
 204	return AE_OK;
 205}
 206
 207static int acpi_scan_try_to_offline(struct acpi_device *device)
 208{
 209	acpi_handle handle = device->handle;
 210	struct device *errdev = NULL;
 211	acpi_status status;
 212
 213	/*
 214	 * Carry out two passes here and ignore errors in the first pass,
 215	 * because if the devices in question are memory blocks and
 216	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
 217	 * that the other blocks depend on, but it is not known in advance which
 218	 * block holds them.
 219	 *
 220	 * If the first pass is successful, the second one isn't needed, though.
 221	 */
 222	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 223				     NULL, acpi_bus_offline, (void *)false,
 224				     (void **)&errdev);
 225	if (status == AE_SUPPORT) {
 226		dev_warn(errdev, "Offline disabled.\n");
 227		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 228				    acpi_bus_online, NULL, NULL, NULL);
 229		return -EPERM;
 230	}
 231	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 232	if (errdev) {
 233		errdev = NULL;
 234		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 235				    NULL, acpi_bus_offline, (void *)true,
 236				    (void **)&errdev);
 237		if (!errdev)
 238			acpi_bus_offline(handle, 0, (void *)true,
 239					 (void **)&errdev);
 240
 241		if (errdev) {
 242			dev_warn(errdev, "Offline failed.\n");
 243			acpi_bus_online(handle, 0, NULL, NULL);
 244			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 245					    ACPI_UINT32_MAX, acpi_bus_online,
 246					    NULL, NULL, NULL);
 247			return -EBUSY;
 248		}
 249	}
 250	return 0;
 251}
 252
 253static int acpi_scan_hot_remove(struct acpi_device *device)
 254{
 255	acpi_handle handle = device->handle;
 256	unsigned long long sta;
 257	acpi_status status;
 258
 259	if (device->handler && device->handler->hotplug.demand_offline) {
 260		if (!acpi_scan_is_offline(device, true))
 261			return -EBUSY;
 262	} else {
 263		int error = acpi_scan_try_to_offline(device);
 264		if (error)
 265			return error;
 266	}
 267
 268	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 269		"Hot-removing device %s...\n", dev_name(&device->dev)));
 270
 271	acpi_bus_trim(device);
 272
 273	acpi_evaluate_lck(handle, 0);
 274	/*
 275	 * TBD: _EJD support.
 276	 */
 277	status = acpi_evaluate_ej0(handle);
 278	if (status == AE_NOT_FOUND)
 279		return -ENODEV;
 280	else if (ACPI_FAILURE(status))
 281		return -EIO;
 282
 283	/*
 284	 * Verify if eject was indeed successful.  If not, log an error
 285	 * message.  No need to call _OST since _EJ0 call was made OK.
 286	 */
 287	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 288	if (ACPI_FAILURE(status)) {
 289		acpi_handle_warn(handle,
 290			"Status check after eject failed (0x%x)\n", status);
 291	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
 292		acpi_handle_warn(handle,
 293			"Eject incomplete - status 0x%llx\n", sta);
 294	}
 295
 296	return 0;
 297}
 298
 299static int acpi_scan_device_not_present(struct acpi_device *adev)
 300{
 301	if (!acpi_device_enumerated(adev)) {
 302		dev_warn(&adev->dev, "Still not present\n");
 303		return -EALREADY;
 304	}
 305	acpi_bus_trim(adev);
 306	return 0;
 307}
 308
 309static int acpi_scan_device_check(struct acpi_device *adev)
 310{
 311	int error;
 312
 313	acpi_bus_get_status(adev);
 314	if (adev->status.present || adev->status.functional) {
 315		/*
 316		 * This function is only called for device objects for which
 317		 * matching scan handlers exist.  The only situation in which
 318		 * the scan handler is not attached to this device object yet
 319		 * is when the device has just appeared (either it wasn't
 320		 * present at all before or it was removed and then added
 321		 * again).
 322		 */
 323		if (adev->handler) {
 324			dev_warn(&adev->dev, "Already enumerated\n");
 325			return -EALREADY;
 326		}
 327		error = acpi_bus_scan(adev->handle);
 328		if (error) {
 329			dev_warn(&adev->dev, "Namespace scan failure\n");
 330			return error;
 331		}
 332		if (!adev->handler) {
 333			dev_warn(&adev->dev, "Enumeration failure\n");
 334			error = -ENODEV;
 335		}
 336	} else {
 337		error = acpi_scan_device_not_present(adev);
 338	}
 339	return error;
 340}
 341
 342static int acpi_scan_bus_check(struct acpi_device *adev)
 343{
 344	struct acpi_scan_handler *handler = adev->handler;
 345	struct acpi_device *child;
 346	int error;
 347
 348	acpi_bus_get_status(adev);
 349	if (!(adev->status.present || adev->status.functional)) {
 350		acpi_scan_device_not_present(adev);
 351		return 0;
 352	}
 353	if (handler && handler->hotplug.scan_dependent)
 354		return handler->hotplug.scan_dependent(adev);
 355
 356	error = acpi_bus_scan(adev->handle);
 357	if (error) {
 358		dev_warn(&adev->dev, "Namespace scan failure\n");
 359		return error;
 360	}
 361	list_for_each_entry(child, &adev->children, node) {
 362		error = acpi_scan_bus_check(child);
 363		if (error)
 364			return error;
 365	}
 366	return 0;
 367}
 368
 369static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 370{
 371	switch (type) {
 372	case ACPI_NOTIFY_BUS_CHECK:
 373		return acpi_scan_bus_check(adev);
 374	case ACPI_NOTIFY_DEVICE_CHECK:
 375		return acpi_scan_device_check(adev);
 376	case ACPI_NOTIFY_EJECT_REQUEST:
 377	case ACPI_OST_EC_OSPM_EJECT:
 378		if (adev->handler && !adev->handler->hotplug.enabled) {
 379			dev_info(&adev->dev, "Eject disabled\n");
 380			return -EPERM;
 381		}
 382		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 383				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 384		return acpi_scan_hot_remove(adev);
 385	}
 386	return -EINVAL;
 387}
 388
 389void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 390{
 391	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 392	int error = -ENODEV;
 393
 394	lock_device_hotplug();
 395	mutex_lock(&acpi_scan_lock);
 396
 397	/*
 398	 * The device object's ACPI handle cannot become invalid as long as we
 399	 * are holding acpi_scan_lock, but it might have become invalid before
 400	 * that lock was acquired.
 401	 */
 402	if (adev->handle == INVALID_ACPI_HANDLE)
 403		goto err_out;
 404
 405	if (adev->flags.is_dock_station) {
 406		error = dock_notify(adev, src);
 407	} else if (adev->flags.hotplug_notify) {
 408		error = acpi_generic_hotplug_event(adev, src);
 409	} else {
 410		int (*notify)(struct acpi_device *, u32);
 411
 412		acpi_lock_hp_context();
 413		notify = adev->hp ? adev->hp->notify : NULL;
 414		acpi_unlock_hp_context();
 415		/*
 416		 * There may be additional notify handlers for device objects
 417		 * without the .event() callback, so ignore them here.
 418		 */
 419		if (notify)
 420			error = notify(adev, src);
 421		else
 422			goto out;
 423	}
 424	switch (error) {
 425	case 0:
 426		ost_code = ACPI_OST_SC_SUCCESS;
 427		break;
 428	case -EPERM:
 429		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 430		break;
 431	case -EBUSY:
 432		ost_code = ACPI_OST_SC_DEVICE_BUSY;
 433		break;
 434	default:
 435		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 436		break;
 437	}
 438
 439 err_out:
 440	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 441
 442 out:
 443	acpi_bus_put_acpi_device(adev);
 444	mutex_unlock(&acpi_scan_lock);
 445	unlock_device_hotplug();
 446}
 447
 448static void acpi_free_power_resources_lists(struct acpi_device *device)
 449{
 450	int i;
 451
 452	if (device->wakeup.flags.valid)
 453		acpi_power_resources_list_free(&device->wakeup.resources);
 454
 455	if (!device->power.flags.power_resources)
 456		return;
 457
 458	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 459		struct acpi_device_power_state *ps = &device->power.states[i];
 460		acpi_power_resources_list_free(&ps->resources);
 461	}
 462}
 463
 464static void acpi_device_release(struct device *dev)
 465{
 466	struct acpi_device *acpi_dev = to_acpi_device(dev);
 467
 468	acpi_free_properties(acpi_dev);
 469	acpi_free_pnp_ids(&acpi_dev->pnp);
 470	acpi_free_power_resources_lists(acpi_dev);
 471	kfree(acpi_dev);
 472}
 473
 474static void acpi_device_del(struct acpi_device *device)
 475{
 476	struct acpi_device_bus_id *acpi_device_bus_id;
 477
 478	mutex_lock(&acpi_device_lock);
 479	if (device->parent)
 480		list_del(&device->node);
 481
 482	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 483		if (!strcmp(acpi_device_bus_id->bus_id,
 484			    acpi_device_hid(device))) {
 485			if (acpi_device_bus_id->instance_no > 0)
 486				acpi_device_bus_id->instance_no--;
 487			else {
 488				list_del(&acpi_device_bus_id->node);
 489				kfree(acpi_device_bus_id);
 490			}
 491			break;
 492		}
 493
 494	list_del(&device->wakeup_list);
 495	mutex_unlock(&acpi_device_lock);
 496
 497	acpi_power_add_remove_device(device, false);
 498	acpi_device_remove_files(device);
 499	if (device->remove)
 500		device->remove(device);
 501
 502	device_del(&device->dev);
 503}
 504
 505static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 506
 507static LIST_HEAD(acpi_device_del_list);
 508static DEFINE_MUTEX(acpi_device_del_lock);
 509
 510static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 511{
 512	for (;;) {
 513		struct acpi_device *adev;
 514
 515		mutex_lock(&acpi_device_del_lock);
 516
 517		if (list_empty(&acpi_device_del_list)) {
 518			mutex_unlock(&acpi_device_del_lock);
 519			break;
 520		}
 521		adev = list_first_entry(&acpi_device_del_list,
 522					struct acpi_device, del_list);
 523		list_del(&adev->del_list);
 524
 525		mutex_unlock(&acpi_device_del_lock);
 526
 527		blocking_notifier_call_chain(&acpi_reconfig_chain,
 528					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
 529
 530		acpi_device_del(adev);
 531		/*
 532		 * Drop references to all power resources that might have been
 533		 * used by the device.
 534		 */
 535		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 536		put_device(&adev->dev);
 537	}
 538}
 539
 540/**
 541 * acpi_scan_drop_device - Drop an ACPI device object.
 542 * @handle: Handle of an ACPI namespace node, not used.
 543 * @context: Address of the ACPI device object to drop.
 544 *
 545 * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 546 * namespace node the device object pointed to by @context is attached to.
 547 *
 548 * The unregistration is carried out asynchronously to avoid running
 549 * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 550 * ensure the correct ordering (the device objects must be unregistered in the
 551 * same order in which the corresponding namespace nodes are deleted).
 552 */
 553static void acpi_scan_drop_device(acpi_handle handle, void *context)
 554{
 555	static DECLARE_WORK(work, acpi_device_del_work_fn);
 556	struct acpi_device *adev = context;
 557
 558	mutex_lock(&acpi_device_del_lock);
 559
 560	/*
 561	 * Use the ACPI hotplug workqueue which is ordered, so this work item
 562	 * won't run after any hotplug work items submitted subsequently.  That
 563	 * prevents attempts to register device objects identical to those being
 564	 * deleted from happening concurrently (such attempts result from
 565	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
 566	 * run after all of the work items submitted previosuly, which helps
 567	 * those work items to ensure that they are not accessing stale device
 568	 * objects.
 569	 */
 570	if (list_empty(&acpi_device_del_list))
 571		acpi_queue_hotplug_work(&work);
 572
 573	list_add_tail(&adev->del_list, &acpi_device_del_list);
 574	/* Make acpi_ns_validate_handle() return NULL for this handle. */
 575	adev->handle = INVALID_ACPI_HANDLE;
 576
 577	mutex_unlock(&acpi_device_del_lock);
 578}
 579
 580static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 581				void (*callback)(void *))
 582{
 583	acpi_status status;
 584
 585	if (!device)
 586		return -EINVAL;
 587
 588	status = acpi_get_data_full(handle, acpi_scan_drop_device,
 589				    (void **)device, callback);
 590	if (ACPI_FAILURE(status) || !*device) {
 591		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 592				  handle));
 593		return -ENODEV;
 594	}
 595	return 0;
 596}
 597
 598int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 599{
 600	return acpi_get_device_data(handle, device, NULL);
 601}
 602EXPORT_SYMBOL(acpi_bus_get_device);
 603
 604static void get_acpi_device(void *dev)
 605{
 606	if (dev)
 607		get_device(&((struct acpi_device *)dev)->dev);
 608}
 609
 610struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 611{
 612	struct acpi_device *adev = NULL;
 613
 614	acpi_get_device_data(handle, &adev, get_acpi_device);
 615	return adev;
 616}
 617
 618void acpi_bus_put_acpi_device(struct acpi_device *adev)
 619{
 620	put_device(&adev->dev);
 621}
 622
 623int acpi_device_add(struct acpi_device *device,
 624		    void (*release)(struct device *))
 625{
 626	int result;
 627	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 628	int found = 0;
 629
 630	if (device->handle) {
 631		acpi_status status;
 632
 633		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 634					  device);
 635		if (ACPI_FAILURE(status)) {
 636			acpi_handle_err(device->handle,
 637					"Unable to attach device data\n");
 638			return -ENODEV;
 639		}
 640	}
 641
 642	/*
 643	 * Linkage
 644	 * -------
 645	 * Link this device to its parent and siblings.
 646	 */
 647	INIT_LIST_HEAD(&device->children);
 648	INIT_LIST_HEAD(&device->node);
 649	INIT_LIST_HEAD(&device->wakeup_list);
 650	INIT_LIST_HEAD(&device->physical_node_list);
 651	INIT_LIST_HEAD(&device->del_list);
 652	mutex_init(&device->physical_node_lock);
 653
 654	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 655	if (!new_bus_id) {
 656		pr_err(PREFIX "Memory allocation error\n");
 657		result = -ENOMEM;
 658		goto err_detach;
 659	}
 660
 661	mutex_lock(&acpi_device_lock);
 662	/*
 663	 * Find suitable bus_id and instance number in acpi_bus_id_list
 664	 * If failed, create one and link it into acpi_bus_id_list
 665	 */
 666	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 667		if (!strcmp(acpi_device_bus_id->bus_id,
 668			    acpi_device_hid(device))) {
 669			acpi_device_bus_id->instance_no++;
 670			found = 1;
 671			kfree(new_bus_id);
 672			break;
 673		}
 674	}
 675	if (!found) {
 676		acpi_device_bus_id = new_bus_id;
 677		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 678		acpi_device_bus_id->instance_no = 0;
 679		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 680	}
 681	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 682
 683	if (device->parent)
 684		list_add_tail(&device->node, &device->parent->children);
 685
 686	if (device->wakeup.flags.valid)
 687		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 688	mutex_unlock(&acpi_device_lock);
 689
 690	if (device->parent)
 691		device->dev.parent = &device->parent->dev;
 692	device->dev.bus = &acpi_bus_type;
 693	device->dev.release = release;
 694	result = device_add(&device->dev);
 695	if (result) {
 696		dev_err(&device->dev, "Error registering device\n");
 697		goto err;
 698	}
 699
 700	result = acpi_device_setup_files(device);
 701	if (result)
 702		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 703		       dev_name(&device->dev));
 704
 705	return 0;
 706
 707 err:
 708	mutex_lock(&acpi_device_lock);
 709	if (device->parent)
 710		list_del(&device->node);
 711	list_del(&device->wakeup_list);
 712	mutex_unlock(&acpi_device_lock);
 713
 714 err_detach:
 715	acpi_detach_data(device->handle, acpi_scan_drop_device);
 716	return result;
 717}
 718
 719/* --------------------------------------------------------------------------
 720                                 Device Enumeration
 721   -------------------------------------------------------------------------- */
 722static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 723{
 724	struct acpi_device *device = NULL;
 725	acpi_status status;
 726
 727	/*
 728	 * Fixed hardware devices do not appear in the namespace and do not
 729	 * have handles, but we fabricate acpi_devices for them, so we have
 730	 * to deal with them specially.
 731	 */
 732	if (!handle)
 733		return acpi_root;
 734
 735	do {
 736		status = acpi_get_parent(handle, &handle);
 737		if (ACPI_FAILURE(status))
 738			return status == AE_NULL_ENTRY ? NULL : acpi_root;
 739	} while (acpi_bus_get_device(handle, &device));
 740	return device;
 741}
 742
 743acpi_status
 744acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 745{
 746	acpi_status status;
 747	acpi_handle tmp;
 748	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 749	union acpi_object *obj;
 750
 751	status = acpi_get_handle(handle, "_EJD", &tmp);
 752	if (ACPI_FAILURE(status))
 753		return status;
 754
 755	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 756	if (ACPI_SUCCESS(status)) {
 757		obj = buffer.pointer;
 758		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 759					 ejd);
 760		kfree(buffer.pointer);
 761	}
 762	return status;
 763}
 764EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 765
 766static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 767					struct acpi_device_wakeup *wakeup)
 768{
 769	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 770	union acpi_object *package = NULL;
 771	union acpi_object *element = NULL;
 772	acpi_status status;
 773	int err = -ENODATA;
 774
 775	if (!wakeup)
 776		return -EINVAL;
 777
 778	INIT_LIST_HEAD(&wakeup->resources);
 779
 780	/* _PRW */
 781	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 782	if (ACPI_FAILURE(status)) {
 783		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 784		return err;
 785	}
 786
 787	package = (union acpi_object *)buffer.pointer;
 788
 789	if (!package || package->package.count < 2)
 790		goto out;
 791
 792	element = &(package->package.elements[0]);
 793	if (!element)
 794		goto out;
 795
 796	if (element->type == ACPI_TYPE_PACKAGE) {
 797		if ((element->package.count < 2) ||
 798		    (element->package.elements[0].type !=
 799		     ACPI_TYPE_LOCAL_REFERENCE)
 800		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 801			goto out;
 802
 803		wakeup->gpe_device =
 804		    element->package.elements[0].reference.handle;
 805		wakeup->gpe_number =
 806		    (u32) element->package.elements[1].integer.value;
 807	} else if (element->type == ACPI_TYPE_INTEGER) {
 808		wakeup->gpe_device = NULL;
 809		wakeup->gpe_number = element->integer.value;
 810	} else {
 811		goto out;
 812	}
 813
 814	element = &(package->package.elements[1]);
 815	if (element->type != ACPI_TYPE_INTEGER)
 816		goto out;
 817
 818	wakeup->sleep_state = element->integer.value;
 819
 820	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 821	if (err)
 822		goto out;
 823
 824	if (!list_empty(&wakeup->resources)) {
 825		int sleep_state;
 826
 827		err = acpi_power_wakeup_list_init(&wakeup->resources,
 828						  &sleep_state);
 829		if (err) {
 830			acpi_handle_warn(handle, "Retrieving current states "
 831					 "of wakeup power resources failed\n");
 832			acpi_power_resources_list_free(&wakeup->resources);
 833			goto out;
 834		}
 835		if (sleep_state < wakeup->sleep_state) {
 836			acpi_handle_warn(handle, "Overriding _PRW sleep state "
 837					 "(S%d) by S%d from power resources\n",
 838					 (int)wakeup->sleep_state, sleep_state);
 839			wakeup->sleep_state = sleep_state;
 840		}
 841	}
 842
 843 out:
 844	kfree(buffer.pointer);
 845	return err;
 846}
 847
 848static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 849{
 850	static const struct acpi_device_id button_device_ids[] = {
 851		{"PNP0C0C", 0},
 852		{"PNP0C0D", 0},
 853		{"PNP0C0E", 0},
 854		{"", 0},
 855	};
 856	struct acpi_device_wakeup *wakeup = &device->wakeup;
 857	acpi_status status;
 858
 859	wakeup->flags.notifier_present = 0;
 860
 861	/* Power button, Lid switch always enable wakeup */
 862	if (!acpi_match_device_ids(device, button_device_ids)) {
 863		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 864			/* Do not use Lid/sleep button for S5 wakeup */
 865			if (wakeup->sleep_state == ACPI_STATE_S5)
 866				wakeup->sleep_state = ACPI_STATE_S4;
 867		}
 868		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 869		device_set_wakeup_capable(&device->dev, true);
 870		return true;
 871	}
 872
 873	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 874					 wakeup->gpe_number);
 875	return ACPI_SUCCESS(status);
 876}
 877
 878static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 879{
 880	int err;
 881
 882	/* Presence of _PRW indicates wake capable */
 883	if (!acpi_has_method(device->handle, "_PRW"))
 884		return;
 885
 886	err = acpi_bus_extract_wakeup_device_power_package(device->handle,
 887							   &device->wakeup);
 888	if (err) {
 889		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 890		return;
 891	}
 892
 893	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
 894	device->wakeup.prepare_count = 0;
 895	/*
 896	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
 897	 * system for the ACPI device with the _PRW object.
 898	 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 899	 * So it is necessary to call _DSW object first. Only when it is not
 900	 * present will the _PSW object used.
 901	 */
 902	err = acpi_device_sleep_wake(device, 0, 0, 0);
 903	if (err)
 904		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 905				"error in _DSW or _PSW evaluation\n"));
 906}
 907
 908static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 909{
 910	struct acpi_device_power_state *ps = &device->power.states[state];
 911	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 912	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 913	acpi_status status;
 914
 915	INIT_LIST_HEAD(&ps->resources);
 916
 917	/* Evaluate "_PRx" to get referenced power resources */
 918	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 919	if (ACPI_SUCCESS(status)) {
 920		union acpi_object *package = buffer.pointer;
 921
 922		if (buffer.length && package
 923		    && package->type == ACPI_TYPE_PACKAGE
 924		    && package->package.count) {
 925			int err = acpi_extract_power_resources(package, 0,
 926							       &ps->resources);
 927			if (!err)
 928				device->power.flags.power_resources = 1;
 929		}
 930		ACPI_FREE(buffer.pointer);
 931	}
 932
 933	/* Evaluate "_PSx" to see if we can do explicit sets */
 934	pathname[2] = 'S';
 935	if (acpi_has_method(device->handle, pathname))
 936		ps->flags.explicit_set = 1;
 937
 938	/* State is valid if there are means to put the device into it. */
 939	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
 940		ps->flags.valid = 1;
 941
 942	ps->power = -1;		/* Unknown - driver assigned */
 943	ps->latency = -1;	/* Unknown - driver assigned */
 944}
 945
 946static void acpi_bus_get_power_flags(struct acpi_device *device)
 947{
 948	u32 i;
 949
 950	/* Presence of _PS0|_PR0 indicates 'power manageable' */
 951	if (!acpi_has_method(device->handle, "_PS0") &&
 952	    !acpi_has_method(device->handle, "_PR0"))
 953		return;
 954
 955	device->flags.power_manageable = 1;
 956
 957	/*
 958	 * Power Management Flags
 959	 */
 960	if (acpi_has_method(device->handle, "_PSC"))
 961		device->power.flags.explicit_get = 1;
 962
 963	if (acpi_has_method(device->handle, "_IRC"))
 964		device->power.flags.inrush_current = 1;
 965
 966	if (acpi_has_method(device->handle, "_DSW"))
 967		device->power.flags.dsw_present = 1;
 968
 969	/*
 970	 * Enumerate supported power management states
 971	 */
 972	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
 973		acpi_bus_init_power_state(device, i);
 974
 975	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
 976	if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 977		device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 978
 979	/* Set defaults for D0 and D3hot states (always valid) */
 980	device->power.states[ACPI_STATE_D0].flags.valid = 1;
 981	device->power.states[ACPI_STATE_D0].power = 100;
 982	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 983
 984	if (acpi_bus_init_power(device))
 985		device->flags.power_manageable = 0;
 986}
 987
 988static void acpi_bus_get_flags(struct acpi_device *device)
 989{
 990	/* Presence of _STA indicates 'dynamic_status' */
 991	if (acpi_has_method(device->handle, "_STA"))
 992		device->flags.dynamic_status = 1;
 993
 994	/* Presence of _RMV indicates 'removable' */
 995	if (acpi_has_method(device->handle, "_RMV"))
 996		device->flags.removable = 1;
 997
 998	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
 999	if (acpi_has_method(device->handle, "_EJD") ||
1000	    acpi_has_method(device->handle, "_EJ0"))
1001		device->flags.ejectable = 1;
1002}
1003
1004static void acpi_device_get_busid(struct acpi_device *device)
1005{
1006	char bus_id[5] = { '?', 0 };
1007	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1008	int i = 0;
1009
1010	/*
1011	 * Bus ID
1012	 * ------
1013	 * The device's Bus ID is simply the object name.
1014	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1015	 */
1016	if (ACPI_IS_ROOT_DEVICE(device)) {
1017		strcpy(device->pnp.bus_id, "ACPI");
1018		return;
1019	}
1020
1021	switch (device->device_type) {
1022	case ACPI_BUS_TYPE_POWER_BUTTON:
1023		strcpy(device->pnp.bus_id, "PWRF");
1024		break;
1025	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1026		strcpy(device->pnp.bus_id, "SLPF");
1027		break;
1028	case ACPI_BUS_TYPE_ECDT_EC:
1029		strcpy(device->pnp.bus_id, "ECDT");
1030		break;
1031	default:
1032		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1033		/* Clean up trailing underscores (if any) */
1034		for (i = 3; i > 1; i--) {
1035			if (bus_id[i] == '_')
1036				bus_id[i] = '\0';
1037			else
1038				break;
1039		}
1040		strcpy(device->pnp.bus_id, bus_id);
1041		break;
1042	}
1043}
1044
1045/*
1046 * acpi_ata_match - see if an acpi object is an ATA device
1047 *
1048 * If an acpi object has one of the ACPI ATA methods defined,
1049 * then we can safely call it an ATA device.
1050 */
1051bool acpi_ata_match(acpi_handle handle)
1052{
1053	return acpi_has_method(handle, "_GTF") ||
1054	       acpi_has_method(handle, "_GTM") ||
1055	       acpi_has_method(handle, "_STM") ||
1056	       acpi_has_method(handle, "_SDD");
1057}
1058
1059/*
1060 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1061 *
1062 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1063 * then we can safely call it an ejectable drive bay
1064 */
1065bool acpi_bay_match(acpi_handle handle)
1066{
1067	acpi_handle phandle;
1068
1069	if (!acpi_has_method(handle, "_EJ0"))
1070		return false;
1071	if (acpi_ata_match(handle))
1072		return true;
1073	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1074		return false;
1075
1076	return acpi_ata_match(phandle);
1077}
1078
1079bool acpi_device_is_battery(struct acpi_device *adev)
1080{
1081	struct acpi_hardware_id *hwid;
1082
1083	list_for_each_entry(hwid, &adev->pnp.ids, list)
1084		if (!strcmp("PNP0C0A", hwid->id))
1085			return true;
1086
1087	return false;
1088}
1089
1090static bool is_ejectable_bay(struct acpi_device *adev)
1091{
1092	acpi_handle handle = adev->handle;
1093
1094	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1095		return true;
1096
1097	return acpi_bay_match(handle);
1098}
1099
1100/*
1101 * acpi_dock_match - see if an acpi object has a _DCK method
1102 */
1103bool acpi_dock_match(acpi_handle handle)
1104{
1105	return acpi_has_method(handle, "_DCK");
1106}
1107
1108static acpi_status
1109acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1110			  void **return_value)
1111{
1112	long *cap = context;
1113
1114	if (acpi_has_method(handle, "_BCM") &&
1115	    acpi_has_method(handle, "_BCL")) {
1116		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1117				  "support\n"));
1118		*cap |= ACPI_VIDEO_BACKLIGHT;
1119		/* We have backlight support, no need to scan further */
1120		return AE_CTRL_TERMINATE;
1121	}
1122	return 0;
1123}
1124
1125/* Returns true if the ACPI object is a video device which can be
1126 * handled by video.ko.
1127 * The device will get a Linux specific CID added in scan.c to
1128 * identify the device as an ACPI graphics device
1129 * Be aware that the graphics device may not be physically present
1130 * Use acpi_video_get_capabilities() to detect general ACPI video
1131 * capabilities of present cards
1132 */
1133long acpi_is_video_device(acpi_handle handle)
1134{
1135	long video_caps = 0;
1136
1137	/* Is this device able to support video switching ? */
1138	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1139		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1140
1141	/* Is this device able to retrieve a video ROM ? */
1142	if (acpi_has_method(handle, "_ROM"))
1143		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1144
1145	/* Is this device able to configure which video head to be POSTed ? */
1146	if (acpi_has_method(handle, "_VPO") &&
1147	    acpi_has_method(handle, "_GPD") &&
1148	    acpi_has_method(handle, "_SPD"))
1149		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1150
1151	/* Only check for backlight functionality if one of the above hit. */
1152	if (video_caps)
1153		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1154				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1155				    &video_caps, NULL);
1156
1157	return video_caps;
1158}
1159EXPORT_SYMBOL(acpi_is_video_device);
1160
1161const char *acpi_device_hid(struct acpi_device *device)
1162{
1163	struct acpi_hardware_id *hid;
1164
1165	if (list_empty(&device->pnp.ids))
1166		return dummy_hid;
1167
1168	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1169	return hid->id;
1170}
1171EXPORT_SYMBOL(acpi_device_hid);
1172
1173static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1174{
1175	struct acpi_hardware_id *id;
1176
1177	id = kmalloc(sizeof(*id), GFP_KERNEL);
1178	if (!id)
1179		return;
1180
1181	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1182	if (!id->id) {
1183		kfree(id);
1184		return;
1185	}
1186
1187	list_add_tail(&id->list, &pnp->ids);
1188	pnp->type.hardware_id = 1;
1189}
1190
1191/*
1192 * Old IBM workstations have a DSDT bug wherein the SMBus object
1193 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1194 * prefix.  Work around this.
1195 */
1196static bool acpi_ibm_smbus_match(acpi_handle handle)
1197{
1198	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1199	struct acpi_buffer path = { sizeof(node_name), node_name };
1200
1201	if (!dmi_name_in_vendors("IBM"))
1202		return false;
1203
1204	/* Look for SMBS object */
1205	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1206	    strcmp("SMBS", path.pointer))
1207		return false;
1208
1209	/* Does it have the necessary (but misnamed) methods? */
1210	if (acpi_has_method(handle, "SBI") &&
1211	    acpi_has_method(handle, "SBR") &&
1212	    acpi_has_method(handle, "SBW"))
1213		return true;
1214
1215	return false;
1216}
1217
1218static bool acpi_object_is_system_bus(acpi_handle handle)
1219{
1220	acpi_handle tmp;
1221
1222	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1223	    tmp == handle)
1224		return true;
1225	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1226	    tmp == handle)
1227		return true;
1228
1229	return false;
1230}
1231
1232static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1233				int device_type)
1234{
1235	acpi_status status;
1236	struct acpi_device_info *info;
1237	struct acpi_pnp_device_id_list *cid_list;
1238	int i;
1239
1240	switch (device_type) {
1241	case ACPI_BUS_TYPE_DEVICE:
1242		if (handle == ACPI_ROOT_OBJECT) {
1243			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1244			break;
1245		}
1246
1247		status = acpi_get_object_info(handle, &info);
1248		if (ACPI_FAILURE(status)) {
1249			pr_err(PREFIX "%s: Error reading device info\n",
1250					__func__);
1251			return;
1252		}
1253
1254		if (info->valid & ACPI_VALID_HID) {
1255			acpi_add_id(pnp, info->hardware_id.string);
1256			pnp->type.platform_id = 1;
1257		}
1258		if (info->valid & ACPI_VALID_CID) {
1259			cid_list = &info->compatible_id_list;
1260			for (i = 0; i < cid_list->count; i++)
1261				acpi_add_id(pnp, cid_list->ids[i].string);
1262		}
1263		if (info->valid & ACPI_VALID_ADR) {
1264			pnp->bus_address = info->address;
1265			pnp->type.bus_address = 1;
1266		}
1267		if (info->valid & ACPI_VALID_UID)
1268			pnp->unique_id = kstrdup(info->unique_id.string,
1269							GFP_KERNEL);
1270		if (info->valid & ACPI_VALID_CLS)
1271			acpi_add_id(pnp, info->class_code.string);
1272
1273		kfree(info);
1274
1275		/*
1276		 * Some devices don't reliably have _HIDs & _CIDs, so add
1277		 * synthetic HIDs to make sure drivers can find them.
1278		 */
1279		if (acpi_is_video_device(handle))
1280			acpi_add_id(pnp, ACPI_VIDEO_HID);
1281		else if (acpi_bay_match(handle))
1282			acpi_add_id(pnp, ACPI_BAY_HID);
1283		else if (acpi_dock_match(handle))
1284			acpi_add_id(pnp, ACPI_DOCK_HID);
1285		else if (acpi_ibm_smbus_match(handle))
1286			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1287		else if (list_empty(&pnp->ids) &&
1288			 acpi_object_is_system_bus(handle)) {
1289			/* \_SB, \_TZ, LNXSYBUS */
1290			acpi_add_id(pnp, ACPI_BUS_HID);
1291			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1292			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1293		}
1294
1295		break;
1296	case ACPI_BUS_TYPE_POWER:
1297		acpi_add_id(pnp, ACPI_POWER_HID);
1298		break;
1299	case ACPI_BUS_TYPE_PROCESSOR:
1300		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1301		break;
1302	case ACPI_BUS_TYPE_THERMAL:
1303		acpi_add_id(pnp, ACPI_THERMAL_HID);
1304		break;
1305	case ACPI_BUS_TYPE_POWER_BUTTON:
1306		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1307		break;
1308	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1309		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1310		break;
1311	case ACPI_BUS_TYPE_ECDT_EC:
1312		acpi_add_id(pnp, ACPI_ECDT_HID);
1313		break;
1314	}
1315}
1316
1317void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1318{
1319	struct acpi_hardware_id *id, *tmp;
1320
1321	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1322		kfree_const(id->id);
1323		kfree(id);
1324	}
1325	kfree(pnp->unique_id);
1326}
1327
1328/**
1329 * acpi_dma_supported - Check DMA support for the specified device.
1330 * @adev: The pointer to acpi device
1331 *
1332 * Return false if DMA is not supported. Otherwise, return true
1333 */
1334bool acpi_dma_supported(struct acpi_device *adev)
1335{
1336	if (!adev)
1337		return false;
1338
1339	if (adev->flags.cca_seen)
1340		return true;
1341
1342	/*
1343	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1344	* DMA on "Intel platforms".  Presumably that includes all x86 and
1345	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1346	*/
1347	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1348		return true;
1349
1350	return false;
1351}
1352
1353/**
1354 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1355 * @adev: The pointer to acpi device
1356 *
1357 * Return enum dev_dma_attr.
1358 */
1359enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1360{
1361	if (!acpi_dma_supported(adev))
1362		return DEV_DMA_NOT_SUPPORTED;
1363
1364	if (adev->flags.coherent_dma)
1365		return DEV_DMA_COHERENT;
1366	else
1367		return DEV_DMA_NON_COHERENT;
1368}
1369
1370/**
1371 * acpi_dma_get_range() - Get device DMA parameters.
1372 *
1373 * @dev: device to configure
1374 * @dma_addr: pointer device DMA address result
1375 * @offset: pointer to the DMA offset result
1376 * @size: pointer to DMA range size result
1377 *
1378 * Evaluate DMA regions and return respectively DMA region start, offset
1379 * and size in dma_addr, offset and size on parsing success; it does not
1380 * update the passed in values on failure.
1381 *
1382 * Return 0 on success, < 0 on failure.
1383 */
1384int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1385		       u64 *size)
1386{
1387	struct acpi_device *adev;
1388	LIST_HEAD(list);
1389	struct resource_entry *rentry;
1390	int ret;
1391	struct device *dma_dev = dev;
1392	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1393
1394	/*
1395	 * Walk the device tree chasing an ACPI companion with a _DMA
1396	 * object while we go. Stop if we find a device with an ACPI
1397	 * companion containing a _DMA method.
1398	 */
1399	do {
1400		adev = ACPI_COMPANION(dma_dev);
1401		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1402			break;
1403
1404		dma_dev = dma_dev->parent;
1405	} while (dma_dev);
1406
1407	if (!dma_dev)
1408		return -ENODEV;
1409
1410	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1411		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1412		return -EINVAL;
1413	}
1414
1415	ret = acpi_dev_get_dma_resources(adev, &list);
1416	if (ret > 0) {
1417		list_for_each_entry(rentry, &list, node) {
1418			if (dma_offset && rentry->offset != dma_offset) {
1419				ret = -EINVAL;
1420				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1421				goto out;
1422			}
1423			dma_offset = rentry->offset;
1424
1425			/* Take lower and upper limits */
1426			if (rentry->res->start < dma_start)
1427				dma_start = rentry->res->start;
1428			if (rentry->res->end > dma_end)
1429				dma_end = rentry->res->end;
1430		}
1431
1432		if (dma_start >= dma_end) {
1433			ret = -EINVAL;
1434			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1435			goto out;
1436		}
1437
1438		*dma_addr = dma_start - dma_offset;
1439		len = dma_end - dma_start;
1440		*size = max(len, len + 1);
1441		*offset = dma_offset;
1442	}
1443 out:
1444	acpi_dev_free_resource_list(&list);
1445
1446	return ret >= 0 ? 0 : ret;
1447}
1448
1449/**
1450 * acpi_dma_configure - Set-up DMA configuration for the device.
1451 * @dev: The pointer to the device
1452 * @attr: device dma attributes
1453 */
1454int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1455{
1456	const struct iommu_ops *iommu;
1457	u64 dma_addr = 0, size = 0;
1458
1459	iort_dma_setup(dev, &dma_addr, &size);
1460
1461	iommu = iort_iommu_configure(dev);
1462	if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1463		return -EPROBE_DEFER;
1464
1465	arch_setup_dma_ops(dev, dma_addr, size,
1466				iommu, attr == DEV_DMA_COHERENT);
1467
1468	return 0;
1469}
1470EXPORT_SYMBOL_GPL(acpi_dma_configure);
1471
1472/**
1473 * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1474 * @dev: The pointer to the device
1475 */
1476void acpi_dma_deconfigure(struct device *dev)
1477{
1478	arch_teardown_dma_ops(dev);
1479}
1480EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1481
1482static void acpi_init_coherency(struct acpi_device *adev)
1483{
1484	unsigned long long cca = 0;
1485	acpi_status status;
1486	struct acpi_device *parent = adev->parent;
1487
1488	if (parent && parent->flags.cca_seen) {
1489		/*
1490		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1491		 * already saw one.
1492		 */
1493		adev->flags.cca_seen = 1;
1494		cca = parent->flags.coherent_dma;
1495	} else {
1496		status = acpi_evaluate_integer(adev->handle, "_CCA",
1497					       NULL, &cca);
1498		if (ACPI_SUCCESS(status))
1499			adev->flags.cca_seen = 1;
1500		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1501			/*
1502			 * If architecture does not specify that _CCA is
1503			 * required for DMA-able devices (e.g. x86),
1504			 * we default to _CCA=1.
1505			 */
1506			cca = 1;
1507		else
1508			acpi_handle_debug(adev->handle,
1509					  "ACPI device is missing _CCA.\n");
1510	}
1511
1512	adev->flags.coherent_dma = cca;
1513}
1514
1515static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1516{
1517	bool *is_serial_bus_slave_p = data;
1518
1519	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1520		return 1;
1521
1522	*is_serial_bus_slave_p = true;
1523
1524	 /* no need to do more checking */
1525	return -1;
1526}
1527
1528static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1529{
1530	struct acpi_device *parent = device->parent;
1531	const struct acpi_device_id indirect_io_hosts[] = {
1532		{"HISI0191", 0},
1533		{}
1534	};
1535
1536	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1537}
1538
1539static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1540{
1541	struct list_head resource_list;
1542	bool is_serial_bus_slave = false;
1543
1544	if (acpi_is_indirect_io_slave(device))
1545		return true;
1546
1547	/* Macs use device properties in lieu of _CRS resources */
1548	if (x86_apple_machine &&
1549	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1550	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1551	     fwnode_property_present(&device->fwnode, "baud")))
1552		return true;
1553
1554	INIT_LIST_HEAD(&resource_list);
1555	acpi_dev_get_resources(device, &resource_list,
1556			       acpi_check_serial_bus_slave,
1557			       &is_serial_bus_slave);
1558	acpi_dev_free_resource_list(&resource_list);
1559
1560	return is_serial_bus_slave;
1561}
1562
1563void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1564			     int type, unsigned long long sta)
1565{
1566	INIT_LIST_HEAD(&device->pnp.ids);
1567	device->device_type = type;
1568	device->handle = handle;
1569	device->parent = acpi_bus_get_parent(handle);
1570	device->fwnode.ops = &acpi_device_fwnode_ops;
1571	acpi_set_device_status(device, sta);
1572	acpi_device_get_busid(device);
1573	acpi_set_pnp_ids(handle, &device->pnp, type);
1574	acpi_init_properties(device);
1575	acpi_bus_get_flags(device);
1576	device->flags.match_driver = false;
1577	device->flags.initialized = true;
1578	device->flags.enumeration_by_parent =
1579		acpi_device_enumeration_by_parent(device);
1580	acpi_device_clear_enumerated(device);
1581	device_initialize(&device->dev);
1582	dev_set_uevent_suppress(&device->dev, true);
1583	acpi_init_coherency(device);
1584	/* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1585	device->dep_unmet = 1;
1586}
1587
1588void acpi_device_add_finalize(struct acpi_device *device)
1589{
1590	dev_set_uevent_suppress(&device->dev, false);
1591	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1592}
1593
1594static int acpi_add_single_object(struct acpi_device **child,
1595				  acpi_handle handle, int type,
1596				  unsigned long long sta)
1597{
1598	int result;
1599	struct acpi_device *device;
1600	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1601
1602	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1603	if (!device) {
1604		printk(KERN_ERR PREFIX "Memory allocation error\n");
1605		return -ENOMEM;
1606	}
1607
1608	acpi_init_device_object(device, handle, type, sta);
1609	/*
1610	 * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1611	 * that we can call acpi_bus_get_status() and use its quirk handling.
1612	 * Note this must be done before the get power-/wakeup_dev-flags calls.
1613	 */
1614	if (type == ACPI_BUS_TYPE_DEVICE)
1615		acpi_bus_get_status(device);
1616
1617	acpi_bus_get_power_flags(device);
1618	acpi_bus_get_wakeup_device_flags(device);
1619
1620	result = acpi_device_add(device, acpi_device_release);
1621	if (result) {
1622		acpi_device_release(&device->dev);
1623		return result;
1624	}
1625
1626	acpi_power_add_remove_device(device, true);
1627	acpi_device_add_finalize(device);
1628	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1629	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1630		dev_name(&device->dev), (char *) buffer.pointer,
1631		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1632	kfree(buffer.pointer);
1633	*child = device;
1634	return 0;
1635}
1636
1637static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1638					    void *context)
1639{
1640	struct resource *res = context;
1641
1642	if (acpi_dev_resource_memory(ares, res))
1643		return AE_CTRL_TERMINATE;
1644
1645	return AE_OK;
1646}
1647
1648static bool acpi_device_should_be_hidden(acpi_handle handle)
1649{
1650	acpi_status status;
1651	struct resource res;
1652
1653	/* Check if it should ignore the UART device */
1654	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1655		return false;
1656
1657	/*
1658	 * The UART device described in SPCR table is assumed to have only one
1659	 * memory resource present. So we only look for the first one here.
1660	 */
1661	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1662				     acpi_get_resource_memory, &res);
1663	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1664		return false;
1665
1666	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1667			 &res.start);
1668
1669	return true;
1670}
1671
1672static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1673				    unsigned long long *sta)
1674{
1675	acpi_status status;
1676	acpi_object_type acpi_type;
1677
1678	status = acpi_get_type(handle, &acpi_type);
1679	if (ACPI_FAILURE(status))
1680		return -ENODEV;
1681
1682	switch (acpi_type) {
1683	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1684	case ACPI_TYPE_DEVICE:
1685		if (acpi_device_should_be_hidden(handle))
1686			return -ENODEV;
1687
1688		*type = ACPI_BUS_TYPE_DEVICE;
1689		/*
1690		 * acpi_add_single_object updates this once we've an acpi_device
1691		 * so that acpi_bus_get_status' quirk handling can be used.
1692		 */
1693		*sta = 0;
1694		break;
1695	case ACPI_TYPE_PROCESSOR:
1696		*type = ACPI_BUS_TYPE_PROCESSOR;
1697		status = acpi_bus_get_status_handle(handle, sta);
1698		if (ACPI_FAILURE(status))
1699			return -ENODEV;
1700		break;
1701	case ACPI_TYPE_THERMAL:
1702		*type = ACPI_BUS_TYPE_THERMAL;
1703		*sta = ACPI_STA_DEFAULT;
1704		break;
1705	case ACPI_TYPE_POWER:
1706		*type = ACPI_BUS_TYPE_POWER;
1707		*sta = ACPI_STA_DEFAULT;
1708		break;
1709	default:
1710		return -ENODEV;
1711	}
1712
1713	return 0;
1714}
1715
1716bool acpi_device_is_present(const struct acpi_device *adev)
1717{
1718	return adev->status.present || adev->status.functional;
1719}
1720
1721static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1722				       const char *idstr,
1723				       const struct acpi_device_id **matchid)
1724{
1725	const struct acpi_device_id *devid;
1726
1727	if (handler->match)
1728		return handler->match(idstr, matchid);
1729
1730	for (devid = handler->ids; devid->id[0]; devid++)
1731		if (!strcmp((char *)devid->id, idstr)) {
1732			if (matchid)
1733				*matchid = devid;
1734
1735			return true;
1736		}
1737
1738	return false;
1739}
1740
1741static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1742					const struct acpi_device_id **matchid)
1743{
1744	struct acpi_scan_handler *handler;
1745
1746	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1747		if (acpi_scan_handler_matching(handler, idstr, matchid))
1748			return handler;
1749
1750	return NULL;
1751}
1752
1753void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1754{
1755	if (!!hotplug->enabled == !!val)
1756		return;
1757
1758	mutex_lock(&acpi_scan_lock);
1759
1760	hotplug->enabled = val;
1761
1762	mutex_unlock(&acpi_scan_lock);
1763}
1764
1765static void acpi_scan_init_hotplug(struct acpi_device *adev)
1766{
1767	struct acpi_hardware_id *hwid;
1768
1769	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1770		acpi_dock_add(adev);
1771		return;
1772	}
1773	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1774		struct acpi_scan_handler *handler;
1775
1776		handler = acpi_scan_match_handler(hwid->id, NULL);
1777		if (handler) {
1778			adev->flags.hotplug_notify = true;
1779			break;
1780		}
1781	}
1782}
1783
1784static void acpi_device_dep_initialize(struct acpi_device *adev)
1785{
1786	struct acpi_dep_data *dep;
1787	struct acpi_handle_list dep_devices;
1788	acpi_status status;
1789	int i;
1790
1791	adev->dep_unmet = 0;
1792
1793	if (!acpi_has_method(adev->handle, "_DEP"))
1794		return;
1795
1796	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1797					&dep_devices);
1798	if (ACPI_FAILURE(status)) {
1799		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1800		return;
1801	}
1802
1803	for (i = 0; i < dep_devices.count; i++) {
1804		struct acpi_device_info *info;
1805		int skip;
1806
1807		status = acpi_get_object_info(dep_devices.handles[i], &info);
1808		if (ACPI_FAILURE(status)) {
1809			dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1810			continue;
1811		}
1812
1813		/*
1814		 * Skip the dependency of Windows System Power
1815		 * Management Controller
1816		 */
1817		skip = info->valid & ACPI_VALID_HID &&
1818			!strcmp(info->hardware_id.string, "INT3396");
1819
1820		kfree(info);
1821
1822		if (skip)
1823			continue;
1824
1825		dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1826		if (!dep)
1827			return;
1828
1829		dep->master = dep_devices.handles[i];
1830		dep->slave  = adev->handle;
1831		adev->dep_unmet++;
1832
1833		mutex_lock(&acpi_dep_list_lock);
1834		list_add_tail(&dep->node , &acpi_dep_list);
1835		mutex_unlock(&acpi_dep_list_lock);
1836	}
1837}
1838
1839static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1840				      void *not_used, void **return_value)
1841{
1842	struct acpi_device *device = NULL;
1843	int type;
1844	unsigned long long sta;
1845	int result;
1846
1847	acpi_bus_get_device(handle, &device);
1848	if (device)
1849		goto out;
1850
1851	result = acpi_bus_type_and_status(handle, &type, &sta);
1852	if (result)
1853		return AE_OK;
1854
1855	if (type == ACPI_BUS_TYPE_POWER) {
1856		acpi_add_power_resource(handle);
1857		return AE_OK;
1858	}
1859
1860	acpi_add_single_object(&device, handle, type, sta);
1861	if (!device)
1862		return AE_CTRL_DEPTH;
1863
1864	acpi_scan_init_hotplug(device);
1865	acpi_device_dep_initialize(device);
1866
1867 out:
1868	if (!*return_value)
1869		*return_value = device;
1870
1871	return AE_OK;
1872}
1873
1874static void acpi_default_enumeration(struct acpi_device *device)
1875{
1876	/*
1877	 * Do not enumerate devices with enumeration_by_parent flag set as
1878	 * they will be enumerated by their respective parents.
1879	 */
1880	if (!device->flags.enumeration_by_parent) {
1881		acpi_create_platform_device(device, NULL);
1882		acpi_device_set_enumerated(device);
1883	} else {
1884		blocking_notifier_call_chain(&acpi_reconfig_chain,
1885					     ACPI_RECONFIG_DEVICE_ADD, device);
1886	}
1887}
1888
1889static const struct acpi_device_id generic_device_ids[] = {
1890	{ACPI_DT_NAMESPACE_HID, },
1891	{"", },
1892};
1893
1894static int acpi_generic_device_attach(struct acpi_device *adev,
1895				      const struct acpi_device_id *not_used)
1896{
1897	/*
1898	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1899	 * below can be unconditional.
1900	 */
1901	if (adev->data.of_compatible)
1902		acpi_default_enumeration(adev);
1903
1904	return 1;
1905}
1906
1907static struct acpi_scan_handler generic_device_handler = {
1908	.ids = generic_device_ids,
1909	.attach = acpi_generic_device_attach,
1910};
1911
1912static int acpi_scan_attach_handler(struct acpi_device *device)
1913{
1914	struct acpi_hardware_id *hwid;
1915	int ret = 0;
1916
1917	list_for_each_entry(hwid, &device->pnp.ids, list) {
1918		const struct acpi_device_id *devid;
1919		struct acpi_scan_handler *handler;
1920
1921		handler = acpi_scan_match_handler(hwid->id, &devid);
1922		if (handler) {
1923			if (!handler->attach) {
1924				device->pnp.type.platform_id = 0;
1925				continue;
1926			}
1927			device->handler = handler;
1928			ret = handler->attach(device, devid);
1929			if (ret > 0)
1930				break;
1931
1932			device->handler = NULL;
1933			if (ret < 0)
1934				break;
1935		}
1936	}
1937
1938	return ret;
1939}
1940
1941static void acpi_bus_attach(struct acpi_device *device)
1942{
1943	struct acpi_device *child;
1944	acpi_handle ejd;
1945	int ret;
1946
1947	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1948		register_dock_dependent_device(device, ejd);
1949
1950	acpi_bus_get_status(device);
1951	/* Skip devices that are not present. */
1952	if (!acpi_device_is_present(device)) {
1953		device->flags.initialized = false;
1954		acpi_device_clear_enumerated(device);
1955		device->flags.power_manageable = 0;
1956		return;
1957	}
1958	if (device->handler)
1959		goto ok;
1960
1961	if (!device->flags.initialized) {
1962		device->flags.power_manageable =
1963			device->power.states[ACPI_STATE_D0].flags.valid;
1964		if (acpi_bus_init_power(device))
1965			device->flags.power_manageable = 0;
1966
1967		device->flags.initialized = true;
1968	} else if (device->flags.visited) {
1969		goto ok;
1970	}
1971
1972	ret = acpi_scan_attach_handler(device);
1973	if (ret < 0)
1974		return;
1975
1976	device->flags.match_driver = true;
1977	if (ret > 0 && !device->flags.enumeration_by_parent) {
1978		acpi_device_set_enumerated(device);
1979		goto ok;
1980	}
1981
1982	ret = device_attach(&device->dev);
1983	if (ret < 0)
1984		return;
1985
1986	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
1987		acpi_default_enumeration(device);
1988	else
1989		acpi_device_set_enumerated(device);
1990
1991 ok:
1992	list_for_each_entry(child, &device->children, node)
1993		acpi_bus_attach(child);
1994
1995	if (device->handler && device->handler->hotplug.notify_online)
1996		device->handler->hotplug.notify_online(device);
1997}
1998
1999void acpi_walk_dep_device_list(acpi_handle handle)
2000{
2001	struct acpi_dep_data *dep, *tmp;
2002	struct acpi_device *adev;
2003
2004	mutex_lock(&acpi_dep_list_lock);
2005	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2006		if (dep->master == handle) {
2007			acpi_bus_get_device(dep->slave, &adev);
2008			if (!adev)
2009				continue;
2010
2011			adev->dep_unmet--;
2012			if (!adev->dep_unmet)
2013				acpi_bus_attach(adev);
2014			list_del(&dep->node);
2015			kfree(dep);
2016		}
2017	}
2018	mutex_unlock(&acpi_dep_list_lock);
2019}
2020EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2021
2022/**
2023 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2024 * @handle: Root of the namespace scope to scan.
2025 *
2026 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2027 * found devices.
2028 *
2029 * If no devices were found, -ENODEV is returned, but it does not mean that
2030 * there has been a real error.  There just have been no suitable ACPI objects
2031 * in the table trunk from which the kernel could create a device and add an
2032 * appropriate driver.
2033 *
2034 * Must be called under acpi_scan_lock.
2035 */
2036int acpi_bus_scan(acpi_handle handle)
2037{
2038	void *device = NULL;
2039
2040	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2041		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2042				    acpi_bus_check_add, NULL, NULL, &device);
2043
2044	if (device) {
2045		acpi_bus_attach(device);
2046		return 0;
2047	}
2048	return -ENODEV;
2049}
2050EXPORT_SYMBOL(acpi_bus_scan);
2051
2052/**
2053 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2054 * @adev: Root of the ACPI namespace scope to walk.
2055 *
2056 * Must be called under acpi_scan_lock.
2057 */
2058void acpi_bus_trim(struct acpi_device *adev)
2059{
2060	struct acpi_scan_handler *handler = adev->handler;
2061	struct acpi_device *child;
2062
2063	list_for_each_entry_reverse(child, &adev->children, node)
2064		acpi_bus_trim(child);
2065
2066	adev->flags.match_driver = false;
2067	if (handler) {
2068		if (handler->detach)
2069			handler->detach(adev);
2070
2071		adev->handler = NULL;
2072	} else {
2073		device_release_driver(&adev->dev);
2074	}
2075	/*
2076	 * Most likely, the device is going away, so put it into D3cold before
2077	 * that.
2078	 */
2079	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2080	adev->flags.initialized = false;
2081	acpi_device_clear_enumerated(adev);
2082}
2083EXPORT_SYMBOL_GPL(acpi_bus_trim);
2084
2085int acpi_bus_register_early_device(int type)
2086{
2087	struct acpi_device *device = NULL;
2088	int result;
2089
2090	result = acpi_add_single_object(&device, NULL,
2091					type, ACPI_STA_DEFAULT);
2092	if (result)
2093		return result;
2094
2095	device->flags.match_driver = true;
2096	return device_attach(&device->dev);
2097}
2098EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2099
2100static int acpi_bus_scan_fixed(void)
2101{
2102	int result = 0;
2103
2104	/*
2105	 * Enumerate all fixed-feature devices.
2106	 */
2107	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2108		struct acpi_device *device = NULL;
2109
2110		result = acpi_add_single_object(&device, NULL,
2111						ACPI_BUS_TYPE_POWER_BUTTON,
2112						ACPI_STA_DEFAULT);
2113		if (result)
2114			return result;
2115
2116		device->flags.match_driver = true;
2117		result = device_attach(&device->dev);
2118		if (result < 0)
2119			return result;
2120
2121		device_init_wakeup(&device->dev, true);
2122	}
2123
2124	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2125		struct acpi_device *device = NULL;
2126
2127		result = acpi_add_single_object(&device, NULL,
2128						ACPI_BUS_TYPE_SLEEP_BUTTON,
2129						ACPI_STA_DEFAULT);
2130		if (result)
2131			return result;
2132
2133		device->flags.match_driver = true;
2134		result = device_attach(&device->dev);
2135	}
2136
2137	return result < 0 ? result : 0;
2138}
2139
2140static void __init acpi_get_spcr_uart_addr(void)
2141{
2142	acpi_status status;
2143	struct acpi_table_spcr *spcr_ptr;
2144
2145	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2146				(struct acpi_table_header **)&spcr_ptr);
2147	if (ACPI_SUCCESS(status))
2148		spcr_uart_addr = spcr_ptr->serial_port.address;
2149	else
2150		printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2151}
2152
2153static bool acpi_scan_initialized;
2154
2155int __init acpi_scan_init(void)
2156{
2157	int result;
2158	acpi_status status;
2159	struct acpi_table_stao *stao_ptr;
2160
2161	acpi_pci_root_init();
2162	acpi_pci_link_init();
2163	acpi_processor_init();
2164	acpi_lpss_init();
2165	acpi_apd_init();
2166	acpi_cmos_rtc_init();
2167	acpi_container_init();
2168	acpi_memory_hotplug_init();
2169	acpi_watchdog_init();
2170	acpi_pnp_init();
2171	acpi_int340x_thermal_init();
2172	acpi_amba_init();
2173	acpi_init_lpit();
2174
2175	acpi_scan_add_handler(&generic_device_handler);
2176
2177	/*
2178	 * If there is STAO table, check whether it needs to ignore the UART
2179	 * device in SPCR table.
2180	 */
2181	status = acpi_get_table(ACPI_SIG_STAO, 0,
2182				(struct acpi_table_header **)&stao_ptr);
2183	if (ACPI_SUCCESS(status)) {
2184		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2185			printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2186
2187		if (stao_ptr->ignore_uart)
2188			acpi_get_spcr_uart_addr();
2189	}
2190
2191	acpi_gpe_apply_masked_gpes();
2192	acpi_update_all_gpes();
2193
2194	mutex_lock(&acpi_scan_lock);
2195	/*
2196	 * Enumerate devices in the ACPI namespace.
2197	 */
2198	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2199	if (result)
2200		goto out;
2201
2202	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2203	if (result)
2204		goto out;
2205
2206	/* Fixed feature devices do not exist on HW-reduced platform */
2207	if (!acpi_gbl_reduced_hardware) {
2208		result = acpi_bus_scan_fixed();
2209		if (result) {
2210			acpi_detach_data(acpi_root->handle,
2211					 acpi_scan_drop_device);
2212			acpi_device_del(acpi_root);
2213			put_device(&acpi_root->dev);
2214			goto out;
2215		}
2216	}
2217
2218	acpi_scan_initialized = true;
2219
2220 out:
2221	mutex_unlock(&acpi_scan_lock);
2222	return result;
2223}
2224
2225static struct acpi_probe_entry *ape;
2226static int acpi_probe_count;
2227static DEFINE_MUTEX(acpi_probe_mutex);
2228
2229static int __init acpi_match_madt(struct acpi_subtable_header *header,
2230				  const unsigned long end)
2231{
2232	if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2233		if (!ape->probe_subtbl(header, end))
2234			acpi_probe_count++;
2235
2236	return 0;
2237}
2238
2239int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2240{
2241	int count = 0;
2242
2243	if (acpi_disabled)
2244		return 0;
2245
2246	mutex_lock(&acpi_probe_mutex);
2247	for (ape = ap_head; nr; ape++, nr--) {
2248		if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2249			acpi_probe_count = 0;
2250			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2251			count += acpi_probe_count;
2252		} else {
2253			int res;
2254			res = acpi_table_parse(ape->id, ape->probe_table);
2255			if (!res)
2256				count++;
2257		}
2258	}
2259	mutex_unlock(&acpi_probe_mutex);
2260
2261	return count;
2262}
2263
2264struct acpi_table_events_work {
2265	struct work_struct work;
2266	void *table;
2267	u32 event;
2268};
2269
2270static void acpi_table_events_fn(struct work_struct *work)
2271{
2272	struct acpi_table_events_work *tew;
2273
2274	tew = container_of(work, struct acpi_table_events_work, work);
2275
2276	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2277		acpi_scan_lock_acquire();
2278		acpi_bus_scan(ACPI_ROOT_OBJECT);
2279		acpi_scan_lock_release();
2280	}
2281
2282	kfree(tew);
2283}
2284
2285void acpi_scan_table_handler(u32 event, void *table, void *context)
2286{
2287	struct acpi_table_events_work *tew;
2288
2289	if (!acpi_scan_initialized)
2290		return;
2291
2292	if (event != ACPI_TABLE_EVENT_LOAD)
2293		return;
2294
2295	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2296	if (!tew)
2297		return;
2298
2299	INIT_WORK(&tew->work, acpi_table_events_fn);
2300	tew->table = table;
2301	tew->event = event;
2302
2303	schedule_work(&tew->work);
2304}
2305
2306int acpi_reconfig_notifier_register(struct notifier_block *nb)
2307{
2308	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2309}
2310EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2311
2312int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2313{
2314	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2315}
2316EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);