1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * scan.c - support for transforming the ACPI namespace into individual objects
   4 */
   5
   6#include <linux/module.h>
   7#include <linux/init.h>
   8#include <linux/slab.h>
   9#include <linux/kernel.h>
  10#include <linux/acpi.h>
  11#include <linux/acpi_iort.h>
  12#include <linux/signal.h>
  13#include <linux/kthread.h>
  14#include <linux/dmi.h>
  15#include <linux/nls.h>
  16#include <linux/dma-mapping.h>
  17#include <linux/platform_data/x86/apple.h>
  18#include <linux/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(struct acpi_device *dev)
 
 767{
 768	acpi_handle handle = dev->handle;
 769	struct acpi_device_wakeup *wakeup = &dev->wakeup;
 770	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 771	union acpi_object *package = NULL;
 772	union acpi_object *element = NULL;
 773	acpi_status status;
 774	int err = -ENODATA;
 775
 
 
 
 776	INIT_LIST_HEAD(&wakeup->resources);
 777
 778	/* _PRW */
 779	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 780	if (ACPI_FAILURE(status)) {
 781		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 782		return err;
 783	}
 784
 785	package = (union acpi_object *)buffer.pointer;
 786
 787	if (!package || package->package.count < 2)
 788		goto out;
 789
 790	element = &(package->package.elements[0]);
 791	if (!element)
 792		goto out;
 793
 794	if (element->type == ACPI_TYPE_PACKAGE) {
 795		if ((element->package.count < 2) ||
 796		    (element->package.elements[0].type !=
 797		     ACPI_TYPE_LOCAL_REFERENCE)
 798		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 799			goto out;
 800
 801		wakeup->gpe_device =
 802		    element->package.elements[0].reference.handle;
 803		wakeup->gpe_number =
 804		    (u32) element->package.elements[1].integer.value;
 805	} else if (element->type == ACPI_TYPE_INTEGER) {
 806		wakeup->gpe_device = NULL;
 807		wakeup->gpe_number = element->integer.value;
 808	} else {
 809		goto out;
 810	}
 811
 812	element = &(package->package.elements[1]);
 813	if (element->type != ACPI_TYPE_INTEGER)
 814		goto out;
 815
 816	wakeup->sleep_state = element->integer.value;
 817
 818	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 819	if (err)
 820		goto out;
 821
 822	if (!list_empty(&wakeup->resources)) {
 823		int sleep_state;
 824
 825		err = acpi_power_wakeup_list_init(&wakeup->resources,
 826						  &sleep_state);
 827		if (err) {
 828			acpi_handle_warn(handle, "Retrieving current states "
 829					 "of wakeup power resources failed\n");
 830			acpi_power_resources_list_free(&wakeup->resources);
 831			goto out;
 832		}
 833		if (sleep_state < wakeup->sleep_state) {
 834			acpi_handle_warn(handle, "Overriding _PRW sleep state "
 835					 "(S%d) by S%d from power resources\n",
 836					 (int)wakeup->sleep_state, sleep_state);
 837			wakeup->sleep_state = sleep_state;
 838		}
 839	}
 840
 841 out:
 842	kfree(buffer.pointer);
 843	return err;
 844}
 845
 846static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 847{
 848	static const struct acpi_device_id button_device_ids[] = {
 849		{"PNP0C0C", 0},		/* Power button */
 850		{"PNP0C0D", 0},		/* Lid */
 851		{"PNP0C0E", 0},		/* Sleep button */
 852		{"", 0},
 853	};
 854	struct acpi_device_wakeup *wakeup = &device->wakeup;
 855	acpi_status status;
 856
 857	wakeup->flags.notifier_present = 0;
 858
 859	/* Power button, Lid switch always enable wakeup */
 860	if (!acpi_match_device_ids(device, button_device_ids)) {
 861		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 862			/* Do not use Lid/sleep button for S5 wakeup */
 863			if (wakeup->sleep_state == ACPI_STATE_S5)
 864				wakeup->sleep_state = ACPI_STATE_S4;
 865		}
 866		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 867		device_set_wakeup_capable(&device->dev, true);
 868		return true;
 869	}
 870
 871	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 872					 wakeup->gpe_number);
 873	return ACPI_SUCCESS(status);
 874}
 875
 876static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 877{
 878	int err;
 879
 880	/* Presence of _PRW indicates wake capable */
 881	if (!acpi_has_method(device->handle, "_PRW"))
 882		return;
 883
 884	err = acpi_bus_extract_wakeup_device_power_package(device);
 
 885	if (err) {
 886		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 887		return;
 888	}
 889
 890	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
 891	device->wakeup.prepare_count = 0;
 892	/*
 893	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
 894	 * system for the ACPI device with the _PRW object.
 895	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
 896	 * So it is necessary to call _DSW object first. Only when it is not
 897	 * present will the _PSW object used.
 898	 */
 899	err = acpi_device_sleep_wake(device, 0, 0, 0);
 900	if (err)
 901		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 902				"error in _DSW or _PSW evaluation\n"));
 903}
 904
 905static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 906{
 907	struct acpi_device_power_state *ps = &device->power.states[state];
 908	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 909	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 910	acpi_status status;
 911
 912	INIT_LIST_HEAD(&ps->resources);
 913
 914	/* Evaluate "_PRx" to get referenced power resources */
 915	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 916	if (ACPI_SUCCESS(status)) {
 917		union acpi_object *package = buffer.pointer;
 918
 919		if (buffer.length && package
 920		    && package->type == ACPI_TYPE_PACKAGE
 921		    && package->package.count)
 922			acpi_extract_power_resources(package, 0, &ps->resources);
 923
 
 
 
 924		ACPI_FREE(buffer.pointer);
 925	}
 926
 927	/* Evaluate "_PSx" to see if we can do explicit sets */
 928	pathname[2] = 'S';
 929	if (acpi_has_method(device->handle, pathname))
 930		ps->flags.explicit_set = 1;
 931
 932	/* State is valid if there are means to put the device into it. */
 933	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
 934		ps->flags.valid = 1;
 935
 936	ps->power = -1;		/* Unknown - driver assigned */
 937	ps->latency = -1;	/* Unknown - driver assigned */
 938}
 939
 940static void acpi_bus_get_power_flags(struct acpi_device *device)
 941{
 942	u32 i;
 943
 944	/* Presence of _PS0|_PR0 indicates 'power manageable' */
 945	if (!acpi_has_method(device->handle, "_PS0") &&
 946	    !acpi_has_method(device->handle, "_PR0"))
 947		return;
 948
 949	device->flags.power_manageable = 1;
 950
 951	/*
 952	 * Power Management Flags
 953	 */
 954	if (acpi_has_method(device->handle, "_PSC"))
 955		device->power.flags.explicit_get = 1;
 956
 957	if (acpi_has_method(device->handle, "_IRC"))
 958		device->power.flags.inrush_current = 1;
 959
 960	if (acpi_has_method(device->handle, "_DSW"))
 961		device->power.flags.dsw_present = 1;
 962
 963	/*
 964	 * Enumerate supported power management states
 965	 */
 966	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
 967		acpi_bus_init_power_state(device, i);
 968
 969	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
 
 
 970
 971	/* Set the defaults for D0 and D3hot (always supported). */
 972	device->power.states[ACPI_STATE_D0].flags.valid = 1;
 973	device->power.states[ACPI_STATE_D0].power = 100;
 974	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 975
 976	/*
 977	 * Use power resources only if the D0 list of them is populated, because
 978	 * some platforms may provide _PR3 only to indicate D3cold support and
 979	 * in those cases the power resources list returned by it may be bogus.
 980	 */
 981	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
 982		device->power.flags.power_resources = 1;
 983		/*
 984		 * D3cold is supported if the D3hot list of power resources is
 985		 * not empty.
 986		 */
 987		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 988			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 989	}
 990
 991	if (acpi_bus_init_power(device))
 992		device->flags.power_manageable = 0;
 993}
 994
 995static void acpi_bus_get_flags(struct acpi_device *device)
 996{
 997	/* Presence of _STA indicates 'dynamic_status' */
 998	if (acpi_has_method(device->handle, "_STA"))
 999		device->flags.dynamic_status = 1;
1000
1001	/* Presence of _RMV indicates 'removable' */
1002	if (acpi_has_method(device->handle, "_RMV"))
1003		device->flags.removable = 1;
1004
1005	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1006	if (acpi_has_method(device->handle, "_EJD") ||
1007	    acpi_has_method(device->handle, "_EJ0"))
1008		device->flags.ejectable = 1;
1009}
1010
1011static void acpi_device_get_busid(struct acpi_device *device)
1012{
1013	char bus_id[5] = { '?', 0 };
1014	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1015	int i = 0;
1016
1017	/*
1018	 * Bus ID
1019	 * ------
1020	 * The device's Bus ID is simply the object name.
1021	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1022	 */
1023	if (ACPI_IS_ROOT_DEVICE(device)) {
1024		strcpy(device->pnp.bus_id, "ACPI");
1025		return;
1026	}
1027
1028	switch (device->device_type) {
1029	case ACPI_BUS_TYPE_POWER_BUTTON:
1030		strcpy(device->pnp.bus_id, "PWRF");
1031		break;
1032	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1033		strcpy(device->pnp.bus_id, "SLPF");
1034		break;
1035	case ACPI_BUS_TYPE_ECDT_EC:
1036		strcpy(device->pnp.bus_id, "ECDT");
1037		break;
1038	default:
1039		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1040		/* Clean up trailing underscores (if any) */
1041		for (i = 3; i > 1; i--) {
1042			if (bus_id[i] == '_')
1043				bus_id[i] = '\0';
1044			else
1045				break;
1046		}
1047		strcpy(device->pnp.bus_id, bus_id);
1048		break;
1049	}
1050}
1051
1052/*
1053 * acpi_ata_match - see if an acpi object is an ATA device
1054 *
1055 * If an acpi object has one of the ACPI ATA methods defined,
1056 * then we can safely call it an ATA device.
1057 */
1058bool acpi_ata_match(acpi_handle handle)
1059{
1060	return acpi_has_method(handle, "_GTF") ||
1061	       acpi_has_method(handle, "_GTM") ||
1062	       acpi_has_method(handle, "_STM") ||
1063	       acpi_has_method(handle, "_SDD");
1064}
1065
1066/*
1067 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1068 *
1069 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1070 * then we can safely call it an ejectable drive bay
1071 */
1072bool acpi_bay_match(acpi_handle handle)
1073{
1074	acpi_handle phandle;
1075
1076	if (!acpi_has_method(handle, "_EJ0"))
1077		return false;
1078	if (acpi_ata_match(handle))
1079		return true;
1080	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1081		return false;
1082
1083	return acpi_ata_match(phandle);
1084}
1085
1086bool acpi_device_is_battery(struct acpi_device *adev)
1087{
1088	struct acpi_hardware_id *hwid;
1089
1090	list_for_each_entry(hwid, &adev->pnp.ids, list)
1091		if (!strcmp("PNP0C0A", hwid->id))
1092			return true;
1093
1094	return false;
1095}
1096
1097static bool is_ejectable_bay(struct acpi_device *adev)
1098{
1099	acpi_handle handle = adev->handle;
1100
1101	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1102		return true;
1103
1104	return acpi_bay_match(handle);
1105}
1106
1107/*
1108 * acpi_dock_match - see if an acpi object has a _DCK method
1109 */
1110bool acpi_dock_match(acpi_handle handle)
1111{
1112	return acpi_has_method(handle, "_DCK");
1113}
1114
1115static acpi_status
1116acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1117			  void **return_value)
1118{
1119	long *cap = context;
1120
1121	if (acpi_has_method(handle, "_BCM") &&
1122	    acpi_has_method(handle, "_BCL")) {
1123		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1124				  "support\n"));
1125		*cap |= ACPI_VIDEO_BACKLIGHT;
1126		/* We have backlight support, no need to scan further */
1127		return AE_CTRL_TERMINATE;
1128	}
1129	return 0;
1130}
1131
1132/* Returns true if the ACPI object is a video device which can be
1133 * handled by video.ko.
1134 * The device will get a Linux specific CID added in scan.c to
1135 * identify the device as an ACPI graphics device
1136 * Be aware that the graphics device may not be physically present
1137 * Use acpi_video_get_capabilities() to detect general ACPI video
1138 * capabilities of present cards
1139 */
1140long acpi_is_video_device(acpi_handle handle)
1141{
1142	long video_caps = 0;
1143
1144	/* Is this device able to support video switching ? */
1145	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1146		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1147
1148	/* Is this device able to retrieve a video ROM ? */
1149	if (acpi_has_method(handle, "_ROM"))
1150		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1151
1152	/* Is this device able to configure which video head to be POSTed ? */
1153	if (acpi_has_method(handle, "_VPO") &&
1154	    acpi_has_method(handle, "_GPD") &&
1155	    acpi_has_method(handle, "_SPD"))
1156		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1157
1158	/* Only check for backlight functionality if one of the above hit. */
1159	if (video_caps)
1160		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1161				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1162				    &video_caps, NULL);
1163
1164	return video_caps;
1165}
1166EXPORT_SYMBOL(acpi_is_video_device);
1167
1168const char *acpi_device_hid(struct acpi_device *device)
1169{
1170	struct acpi_hardware_id *hid;
1171
1172	if (list_empty(&device->pnp.ids))
1173		return dummy_hid;
1174
1175	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1176	return hid->id;
1177}
1178EXPORT_SYMBOL(acpi_device_hid);
1179
1180static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1181{
1182	struct acpi_hardware_id *id;
1183
1184	id = kmalloc(sizeof(*id), GFP_KERNEL);
1185	if (!id)
1186		return;
1187
1188	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1189	if (!id->id) {
1190		kfree(id);
1191		return;
1192	}
1193
1194	list_add_tail(&id->list, &pnp->ids);
1195	pnp->type.hardware_id = 1;
1196}
1197
1198/*
1199 * Old IBM workstations have a DSDT bug wherein the SMBus object
1200 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1201 * prefix.  Work around this.
1202 */
1203static bool acpi_ibm_smbus_match(acpi_handle handle)
1204{
1205	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1206	struct acpi_buffer path = { sizeof(node_name), node_name };
1207
1208	if (!dmi_name_in_vendors("IBM"))
1209		return false;
1210
1211	/* Look for SMBS object */
1212	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1213	    strcmp("SMBS", path.pointer))
1214		return false;
1215
1216	/* Does it have the necessary (but misnamed) methods? */
1217	if (acpi_has_method(handle, "SBI") &&
1218	    acpi_has_method(handle, "SBR") &&
1219	    acpi_has_method(handle, "SBW"))
1220		return true;
1221
1222	return false;
1223}
1224
1225static bool acpi_object_is_system_bus(acpi_handle handle)
1226{
1227	acpi_handle tmp;
1228
1229	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1230	    tmp == handle)
1231		return true;
1232	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1233	    tmp == handle)
1234		return true;
1235
1236	return false;
1237}
1238
1239static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1240				int device_type)
1241{
1242	acpi_status status;
1243	struct acpi_device_info *info;
1244	struct acpi_pnp_device_id_list *cid_list;
1245	int i;
1246
1247	switch (device_type) {
1248	case ACPI_BUS_TYPE_DEVICE:
1249		if (handle == ACPI_ROOT_OBJECT) {
1250			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1251			break;
1252		}
1253
1254		status = acpi_get_object_info(handle, &info);
1255		if (ACPI_FAILURE(status)) {
1256			pr_err(PREFIX "%s: Error reading device info\n",
1257					__func__);
1258			return;
1259		}
1260
1261		if (info->valid & ACPI_VALID_HID) {
1262			acpi_add_id(pnp, info->hardware_id.string);
1263			pnp->type.platform_id = 1;
1264		}
1265		if (info->valid & ACPI_VALID_CID) {
1266			cid_list = &info->compatible_id_list;
1267			for (i = 0; i < cid_list->count; i++)
1268				acpi_add_id(pnp, cid_list->ids[i].string);
1269		}
1270		if (info->valid & ACPI_VALID_ADR) {
1271			pnp->bus_address = info->address;
1272			pnp->type.bus_address = 1;
1273		}
1274		if (info->valid & ACPI_VALID_UID)
1275			pnp->unique_id = kstrdup(info->unique_id.string,
1276							GFP_KERNEL);
1277		if (info->valid & ACPI_VALID_CLS)
1278			acpi_add_id(pnp, info->class_code.string);
1279
1280		kfree(info);
1281
1282		/*
1283		 * Some devices don't reliably have _HIDs & _CIDs, so add
1284		 * synthetic HIDs to make sure drivers can find them.
1285		 */
1286		if (acpi_is_video_device(handle))
1287			acpi_add_id(pnp, ACPI_VIDEO_HID);
1288		else if (acpi_bay_match(handle))
1289			acpi_add_id(pnp, ACPI_BAY_HID);
1290		else if (acpi_dock_match(handle))
1291			acpi_add_id(pnp, ACPI_DOCK_HID);
1292		else if (acpi_ibm_smbus_match(handle))
1293			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1294		else if (list_empty(&pnp->ids) &&
1295			 acpi_object_is_system_bus(handle)) {
1296			/* \_SB, \_TZ, LNXSYBUS */
1297			acpi_add_id(pnp, ACPI_BUS_HID);
1298			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1299			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1300		}
1301
1302		break;
1303	case ACPI_BUS_TYPE_POWER:
1304		acpi_add_id(pnp, ACPI_POWER_HID);
1305		break;
1306	case ACPI_BUS_TYPE_PROCESSOR:
1307		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1308		break;
1309	case ACPI_BUS_TYPE_THERMAL:
1310		acpi_add_id(pnp, ACPI_THERMAL_HID);
1311		break;
1312	case ACPI_BUS_TYPE_POWER_BUTTON:
1313		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1314		break;
1315	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1316		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1317		break;
1318	case ACPI_BUS_TYPE_ECDT_EC:
1319		acpi_add_id(pnp, ACPI_ECDT_HID);
1320		break;
1321	}
1322}
1323
1324void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1325{
1326	struct acpi_hardware_id *id, *tmp;
1327
1328	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1329		kfree_const(id->id);
1330		kfree(id);
1331	}
1332	kfree(pnp->unique_id);
1333}
1334
1335/**
1336 * acpi_dma_supported - Check DMA support for the specified device.
1337 * @adev: The pointer to acpi device
1338 *
1339 * Return false if DMA is not supported. Otherwise, return true
1340 */
1341bool acpi_dma_supported(struct acpi_device *adev)
1342{
1343	if (!adev)
1344		return false;
1345
1346	if (adev->flags.cca_seen)
1347		return true;
1348
1349	/*
1350	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1351	* DMA on "Intel platforms".  Presumably that includes all x86 and
1352	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1353	*/
1354	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1355		return true;
1356
1357	return false;
1358}
1359
1360/**
1361 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1362 * @adev: The pointer to acpi device
1363 *
1364 * Return enum dev_dma_attr.
1365 */
1366enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1367{
1368	if (!acpi_dma_supported(adev))
1369		return DEV_DMA_NOT_SUPPORTED;
1370
1371	if (adev->flags.coherent_dma)
1372		return DEV_DMA_COHERENT;
1373	else
1374		return DEV_DMA_NON_COHERENT;
1375}
1376
1377/**
1378 * acpi_dma_get_range() - Get device DMA parameters.
1379 *
1380 * @dev: device to configure
1381 * @dma_addr: pointer device DMA address result
1382 * @offset: pointer to the DMA offset result
1383 * @size: pointer to DMA range size result
1384 *
1385 * Evaluate DMA regions and return respectively DMA region start, offset
1386 * and size in dma_addr, offset and size on parsing success; it does not
1387 * update the passed in values on failure.
1388 *
1389 * Return 0 on success, < 0 on failure.
1390 */
1391int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1392		       u64 *size)
1393{
1394	struct acpi_device *adev;
1395	LIST_HEAD(list);
1396	struct resource_entry *rentry;
1397	int ret;
1398	struct device *dma_dev = dev;
1399	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1400
1401	/*
1402	 * Walk the device tree chasing an ACPI companion with a _DMA
1403	 * object while we go. Stop if we find a device with an ACPI
1404	 * companion containing a _DMA method.
1405	 */
1406	do {
1407		adev = ACPI_COMPANION(dma_dev);
1408		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1409			break;
1410
1411		dma_dev = dma_dev->parent;
1412	} while (dma_dev);
1413
1414	if (!dma_dev)
1415		return -ENODEV;
1416
1417	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1418		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1419		return -EINVAL;
1420	}
1421
1422	ret = acpi_dev_get_dma_resources(adev, &list);
1423	if (ret > 0) {
1424		list_for_each_entry(rentry, &list, node) {
1425			if (dma_offset && rentry->offset != dma_offset) {
1426				ret = -EINVAL;
1427				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1428				goto out;
1429			}
1430			dma_offset = rentry->offset;
1431
1432			/* Take lower and upper limits */
1433			if (rentry->res->start < dma_start)
1434				dma_start = rentry->res->start;
1435			if (rentry->res->end > dma_end)
1436				dma_end = rentry->res->end;
1437		}
1438
1439		if (dma_start >= dma_end) {
1440			ret = -EINVAL;
1441			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1442			goto out;
1443		}
1444
1445		*dma_addr = dma_start - dma_offset;
1446		len = dma_end - dma_start;
1447		*size = max(len, len + 1);
1448		*offset = dma_offset;
1449	}
1450 out:
1451	acpi_dev_free_resource_list(&list);
1452
1453	return ret >= 0 ? 0 : ret;
1454}
1455
1456/**
1457 * acpi_dma_configure - Set-up DMA configuration for the device.
1458 * @dev: The pointer to the device
1459 * @attr: device dma attributes
1460 * @input_id: input device id const value pointer
1461 */
1462int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1463			  const u32 *input_id)
1464{
1465	const struct iommu_ops *iommu;
1466	u64 dma_addr = 0, size = 0;
1467
1468	if (attr == DEV_DMA_NOT_SUPPORTED) {
1469		set_dma_ops(dev, &dma_dummy_ops);
1470		return 0;
1471	}
1472
1473	iort_dma_setup(dev, &dma_addr, &size);
1474
1475	iommu = iort_iommu_configure_id(dev, input_id);
1476	if (PTR_ERR(iommu) == -EPROBE_DEFER)
1477		return -EPROBE_DEFER;
1478
1479	arch_setup_dma_ops(dev, dma_addr, size,
1480				iommu, attr == DEV_DMA_COHERENT);
1481
1482	return 0;
1483}
1484EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
 
 
 
 
 
 
 
 
 
 
1485
1486static void acpi_init_coherency(struct acpi_device *adev)
1487{
1488	unsigned long long cca = 0;
1489	acpi_status status;
1490	struct acpi_device *parent = adev->parent;
1491
1492	if (parent && parent->flags.cca_seen) {
1493		/*
1494		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1495		 * already saw one.
1496		 */
1497		adev->flags.cca_seen = 1;
1498		cca = parent->flags.coherent_dma;
1499	} else {
1500		status = acpi_evaluate_integer(adev->handle, "_CCA",
1501					       NULL, &cca);
1502		if (ACPI_SUCCESS(status))
1503			adev->flags.cca_seen = 1;
1504		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1505			/*
1506			 * If architecture does not specify that _CCA is
1507			 * required for DMA-able devices (e.g. x86),
1508			 * we default to _CCA=1.
1509			 */
1510			cca = 1;
1511		else
1512			acpi_handle_debug(adev->handle,
1513					  "ACPI device is missing _CCA.\n");
1514	}
1515
1516	adev->flags.coherent_dma = cca;
1517}
1518
1519static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1520{
1521	bool *is_serial_bus_slave_p = data;
1522
1523	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1524		return 1;
1525
1526	*is_serial_bus_slave_p = true;
1527
1528	 /* no need to do more checking */
1529	return -1;
1530}
1531
1532static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1533{
1534	struct acpi_device *parent = device->parent;
1535	static const struct acpi_device_id indirect_io_hosts[] = {
1536		{"HISI0191", 0},
1537		{}
1538	};
1539
1540	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1541}
1542
1543static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1544{
1545	struct list_head resource_list;
1546	bool is_serial_bus_slave = false;
1547	/*
1548	 * These devices have multiple I2cSerialBus resources and an i2c-client
1549	 * must be instantiated for each, each with its own i2c_device_id.
1550	 * Normally we only instantiate an i2c-client for the first resource,
1551	 * using the ACPI HID as id. These special cases are handled by the
1552	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1553	 * which i2c_device_id to use for each resource.
1554	 */
1555	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1556		{"BSG1160", },
1557		{"BSG2150", },
1558		{"INT33FE", },
1559		{"INT3515", },
1560		{}
1561	};
1562
1563	if (acpi_is_indirect_io_slave(device))
1564		return true;
1565
1566	/* Macs use device properties in lieu of _CRS resources */
1567	if (x86_apple_machine &&
1568	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1569	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1570	     fwnode_property_present(&device->fwnode, "baud")))
1571		return true;
1572
1573	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1574	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1575		return false;
1576
1577	INIT_LIST_HEAD(&resource_list);
1578	acpi_dev_get_resources(device, &resource_list,
1579			       acpi_check_serial_bus_slave,
1580			       &is_serial_bus_slave);
1581	acpi_dev_free_resource_list(&resource_list);
1582
1583	return is_serial_bus_slave;
1584}
1585
1586void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1587			     int type, unsigned long long sta)
1588{
1589	INIT_LIST_HEAD(&device->pnp.ids);
1590	device->device_type = type;
1591	device->handle = handle;
1592	device->parent = acpi_bus_get_parent(handle);
1593	device->fwnode.ops = &acpi_device_fwnode_ops;
1594	acpi_set_device_status(device, sta);
1595	acpi_device_get_busid(device);
1596	acpi_set_pnp_ids(handle, &device->pnp, type);
1597	acpi_init_properties(device);
1598	acpi_bus_get_flags(device);
1599	device->flags.match_driver = false;
1600	device->flags.initialized = true;
1601	device->flags.enumeration_by_parent =
1602		acpi_device_enumeration_by_parent(device);
1603	acpi_device_clear_enumerated(device);
1604	device_initialize(&device->dev);
1605	dev_set_uevent_suppress(&device->dev, true);
1606	acpi_init_coherency(device);
1607	/* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1608	device->dep_unmet = 1;
1609}
1610
1611void acpi_device_add_finalize(struct acpi_device *device)
1612{
1613	dev_set_uevent_suppress(&device->dev, false);
1614	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1615}
1616
1617static int acpi_add_single_object(struct acpi_device **child,
1618				  acpi_handle handle, int type,
1619				  unsigned long long sta)
1620{
1621	int result;
1622	struct acpi_device *device;
1623	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1624
1625	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1626	if (!device) {
1627		printk(KERN_ERR PREFIX "Memory allocation error\n");
1628		return -ENOMEM;
1629	}
1630
1631	acpi_init_device_object(device, handle, type, sta);
1632	/*
1633	 * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1634	 * that we can call acpi_bus_get_status() and use its quirk handling.
1635	 * Note this must be done before the get power-/wakeup_dev-flags calls.
1636	 */
1637	if (type == ACPI_BUS_TYPE_DEVICE)
1638		if (acpi_bus_get_status(device) < 0)
1639			acpi_set_device_status(device, 0);
1640
1641	acpi_bus_get_power_flags(device);
1642	acpi_bus_get_wakeup_device_flags(device);
1643
1644	result = acpi_device_add(device, acpi_device_release);
1645	if (result) {
1646		acpi_device_release(&device->dev);
1647		return result;
1648	}
1649
1650	acpi_power_add_remove_device(device, true);
1651	acpi_device_add_finalize(device);
1652	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1653	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1654		dev_name(&device->dev), (char *) buffer.pointer,
1655		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1656	kfree(buffer.pointer);
1657	*child = device;
1658	return 0;
1659}
1660
1661static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1662					    void *context)
1663{
1664	struct resource *res = context;
1665
1666	if (acpi_dev_resource_memory(ares, res))
1667		return AE_CTRL_TERMINATE;
1668
1669	return AE_OK;
1670}
1671
1672static bool acpi_device_should_be_hidden(acpi_handle handle)
1673{
1674	acpi_status status;
1675	struct resource res;
1676
1677	/* Check if it should ignore the UART device */
1678	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1679		return false;
1680
1681	/*
1682	 * The UART device described in SPCR table is assumed to have only one
1683	 * memory resource present. So we only look for the first one here.
1684	 */
1685	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1686				     acpi_get_resource_memory, &res);
1687	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1688		return false;
1689
1690	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1691			 &res.start);
1692
1693	return true;
1694}
1695
1696static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1697				    unsigned long long *sta)
1698{
1699	acpi_status status;
1700	acpi_object_type acpi_type;
1701
1702	status = acpi_get_type(handle, &acpi_type);
1703	if (ACPI_FAILURE(status))
1704		return -ENODEV;
1705
1706	switch (acpi_type) {
1707	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1708	case ACPI_TYPE_DEVICE:
1709		if (acpi_device_should_be_hidden(handle))
1710			return -ENODEV;
1711
1712		*type = ACPI_BUS_TYPE_DEVICE;
1713		/*
1714		 * acpi_add_single_object updates this once we've an acpi_device
1715		 * so that acpi_bus_get_status' quirk handling can be used.
1716		 */
1717		*sta = ACPI_STA_DEFAULT;
1718		break;
1719	case ACPI_TYPE_PROCESSOR:
1720		*type = ACPI_BUS_TYPE_PROCESSOR;
1721		status = acpi_bus_get_status_handle(handle, sta);
1722		if (ACPI_FAILURE(status))
1723			return -ENODEV;
1724		break;
1725	case ACPI_TYPE_THERMAL:
1726		*type = ACPI_BUS_TYPE_THERMAL;
1727		*sta = ACPI_STA_DEFAULT;
1728		break;
1729	case ACPI_TYPE_POWER:
1730		*type = ACPI_BUS_TYPE_POWER;
1731		*sta = ACPI_STA_DEFAULT;
1732		break;
1733	default:
1734		return -ENODEV;
1735	}
1736
1737	return 0;
1738}
1739
1740bool acpi_device_is_present(const struct acpi_device *adev)
1741{
1742	return adev->status.present || adev->status.functional;
1743}
1744
1745static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1746				       const char *idstr,
1747				       const struct acpi_device_id **matchid)
1748{
1749	const struct acpi_device_id *devid;
1750
1751	if (handler->match)
1752		return handler->match(idstr, matchid);
1753
1754	for (devid = handler->ids; devid->id[0]; devid++)
1755		if (!strcmp((char *)devid->id, idstr)) {
1756			if (matchid)
1757				*matchid = devid;
1758
1759			return true;
1760		}
1761
1762	return false;
1763}
1764
1765static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1766					const struct acpi_device_id **matchid)
1767{
1768	struct acpi_scan_handler *handler;
1769
1770	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1771		if (acpi_scan_handler_matching(handler, idstr, matchid))
1772			return handler;
1773
1774	return NULL;
1775}
1776
1777void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1778{
1779	if (!!hotplug->enabled == !!val)
1780		return;
1781
1782	mutex_lock(&acpi_scan_lock);
1783
1784	hotplug->enabled = val;
1785
1786	mutex_unlock(&acpi_scan_lock);
1787}
1788
1789static void acpi_scan_init_hotplug(struct acpi_device *adev)
1790{
1791	struct acpi_hardware_id *hwid;
1792
1793	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1794		acpi_dock_add(adev);
1795		return;
1796	}
1797	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1798		struct acpi_scan_handler *handler;
1799
1800		handler = acpi_scan_match_handler(hwid->id, NULL);
1801		if (handler) {
1802			adev->flags.hotplug_notify = true;
1803			break;
1804		}
1805	}
1806}
1807
1808static void acpi_device_dep_initialize(struct acpi_device *adev)
1809{
1810	struct acpi_dep_data *dep;
1811	struct acpi_handle_list dep_devices;
1812	acpi_status status;
1813	int i;
1814
1815	adev->dep_unmet = 0;
1816
1817	if (!acpi_has_method(adev->handle, "_DEP"))
1818		return;
1819
1820	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1821					&dep_devices);
1822	if (ACPI_FAILURE(status)) {
1823		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1824		return;
1825	}
1826
1827	for (i = 0; i < dep_devices.count; i++) {
1828		struct acpi_device_info *info;
1829		int skip;
1830
1831		status = acpi_get_object_info(dep_devices.handles[i], &info);
1832		if (ACPI_FAILURE(status)) {
1833			dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1834			continue;
1835		}
1836
1837		/*
1838		 * Skip the dependency of Windows System Power
1839		 * Management Controller
1840		 */
1841		skip = info->valid & ACPI_VALID_HID &&
1842			!strcmp(info->hardware_id.string, "INT3396");
1843
1844		kfree(info);
1845
1846		if (skip)
1847			continue;
1848
1849		dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1850		if (!dep)
1851			return;
1852
1853		dep->master = dep_devices.handles[i];
1854		dep->slave  = adev->handle;
1855		adev->dep_unmet++;
1856
1857		mutex_lock(&acpi_dep_list_lock);
1858		list_add_tail(&dep->node , &acpi_dep_list);
1859		mutex_unlock(&acpi_dep_list_lock);
1860	}
1861}
1862
1863static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1864				      void *not_used, void **return_value)
1865{
1866	struct acpi_device *device = NULL;
1867	int type;
1868	unsigned long long sta;
1869	int result;
1870
1871	acpi_bus_get_device(handle, &device);
1872	if (device)
1873		goto out;
1874
1875	result = acpi_bus_type_and_status(handle, &type, &sta);
1876	if (result)
1877		return AE_OK;
1878
1879	if (type == ACPI_BUS_TYPE_POWER) {
1880		acpi_add_power_resource(handle);
1881		return AE_OK;
1882	}
1883
1884	acpi_add_single_object(&device, handle, type, sta);
1885	if (!device)
1886		return AE_CTRL_DEPTH;
1887
1888	acpi_scan_init_hotplug(device);
1889	acpi_device_dep_initialize(device);
1890
1891 out:
1892	if (!*return_value)
1893		*return_value = device;
1894
1895	return AE_OK;
1896}
1897
1898static void acpi_default_enumeration(struct acpi_device *device)
1899{
1900	/*
1901	 * Do not enumerate devices with enumeration_by_parent flag set as
1902	 * they will be enumerated by their respective parents.
1903	 */
1904	if (!device->flags.enumeration_by_parent) {
1905		acpi_create_platform_device(device, NULL);
1906		acpi_device_set_enumerated(device);
1907	} else {
1908		blocking_notifier_call_chain(&acpi_reconfig_chain,
1909					     ACPI_RECONFIG_DEVICE_ADD, device);
1910	}
1911}
1912
1913static const struct acpi_device_id generic_device_ids[] = {
1914	{ACPI_DT_NAMESPACE_HID, },
1915	{"", },
1916};
1917
1918static int acpi_generic_device_attach(struct acpi_device *adev,
1919				      const struct acpi_device_id *not_used)
1920{
1921	/*
1922	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1923	 * below can be unconditional.
1924	 */
1925	if (adev->data.of_compatible)
1926		acpi_default_enumeration(adev);
1927
1928	return 1;
1929}
1930
1931static struct acpi_scan_handler generic_device_handler = {
1932	.ids = generic_device_ids,
1933	.attach = acpi_generic_device_attach,
1934};
1935
1936static int acpi_scan_attach_handler(struct acpi_device *device)
1937{
1938	struct acpi_hardware_id *hwid;
1939	int ret = 0;
1940
1941	list_for_each_entry(hwid, &device->pnp.ids, list) {
1942		const struct acpi_device_id *devid;
1943		struct acpi_scan_handler *handler;
1944
1945		handler = acpi_scan_match_handler(hwid->id, &devid);
1946		if (handler) {
1947			if (!handler->attach) {
1948				device->pnp.type.platform_id = 0;
1949				continue;
1950			}
1951			device->handler = handler;
1952			ret = handler->attach(device, devid);
1953			if (ret > 0)
1954				break;
1955
1956			device->handler = NULL;
1957			if (ret < 0)
1958				break;
1959		}
1960	}
1961
1962	return ret;
1963}
1964
1965static void acpi_bus_attach(struct acpi_device *device)
1966{
1967	struct acpi_device *child;
1968	acpi_handle ejd;
1969	int ret;
1970
1971	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1972		register_dock_dependent_device(device, ejd);
1973
1974	acpi_bus_get_status(device);
1975	/* Skip devices that are not present. */
1976	if (!acpi_device_is_present(device)) {
1977		device->flags.initialized = false;
1978		acpi_device_clear_enumerated(device);
1979		device->flags.power_manageable = 0;
1980		return;
1981	}
1982	if (device->handler)
1983		goto ok;
1984
1985	if (!device->flags.initialized) {
1986		device->flags.power_manageable =
1987			device->power.states[ACPI_STATE_D0].flags.valid;
1988		if (acpi_bus_init_power(device))
1989			device->flags.power_manageable = 0;
1990
1991		device->flags.initialized = true;
1992	} else if (device->flags.visited) {
1993		goto ok;
1994	}
1995
1996	ret = acpi_scan_attach_handler(device);
1997	if (ret < 0)
1998		return;
1999
2000	device->flags.match_driver = true;
2001	if (ret > 0 && !device->flags.enumeration_by_parent) {
2002		acpi_device_set_enumerated(device);
2003		goto ok;
2004	}
2005
2006	ret = device_attach(&device->dev);
2007	if (ret < 0)
2008		return;
2009
2010	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2011		acpi_default_enumeration(device);
2012	else
2013		acpi_device_set_enumerated(device);
2014
2015 ok:
2016	list_for_each_entry(child, &device->children, node)
2017		acpi_bus_attach(child);
2018
2019	if (device->handler && device->handler->hotplug.notify_online)
2020		device->handler->hotplug.notify_online(device);
2021}
2022
2023void acpi_walk_dep_device_list(acpi_handle handle)
2024{
2025	struct acpi_dep_data *dep, *tmp;
2026	struct acpi_device *adev;
2027
2028	mutex_lock(&acpi_dep_list_lock);
2029	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2030		if (dep->master == handle) {
2031			acpi_bus_get_device(dep->slave, &adev);
2032			if (!adev)
2033				continue;
2034
2035			adev->dep_unmet--;
2036			if (!adev->dep_unmet)
2037				acpi_bus_attach(adev);
2038			list_del(&dep->node);
2039			kfree(dep);
2040		}
2041	}
2042	mutex_unlock(&acpi_dep_list_lock);
2043}
2044EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2045
2046/**
2047 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2048 * @handle: Root of the namespace scope to scan.
2049 *
2050 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2051 * found devices.
2052 *
2053 * If no devices were found, -ENODEV is returned, but it does not mean that
2054 * there has been a real error.  There just have been no suitable ACPI objects
2055 * in the table trunk from which the kernel could create a device and add an
2056 * appropriate driver.
2057 *
2058 * Must be called under acpi_scan_lock.
2059 */
2060int acpi_bus_scan(acpi_handle handle)
2061{
2062	void *device = NULL;
2063
2064	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2065		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2066				    acpi_bus_check_add, NULL, NULL, &device);
2067
2068	if (device) {
2069		acpi_bus_attach(device);
2070		return 0;
2071	}
2072	return -ENODEV;
2073}
2074EXPORT_SYMBOL(acpi_bus_scan);
2075
2076/**
2077 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2078 * @adev: Root of the ACPI namespace scope to walk.
2079 *
2080 * Must be called under acpi_scan_lock.
2081 */
2082void acpi_bus_trim(struct acpi_device *adev)
2083{
2084	struct acpi_scan_handler *handler = adev->handler;
2085	struct acpi_device *child;
2086
2087	list_for_each_entry_reverse(child, &adev->children, node)
2088		acpi_bus_trim(child);
2089
2090	adev->flags.match_driver = false;
2091	if (handler) {
2092		if (handler->detach)
2093			handler->detach(adev);
2094
2095		adev->handler = NULL;
2096	} else {
2097		device_release_driver(&adev->dev);
2098	}
2099	/*
2100	 * Most likely, the device is going away, so put it into D3cold before
2101	 * that.
2102	 */
2103	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2104	adev->flags.initialized = false;
2105	acpi_device_clear_enumerated(adev);
2106}
2107EXPORT_SYMBOL_GPL(acpi_bus_trim);
2108
2109int acpi_bus_register_early_device(int type)
2110{
2111	struct acpi_device *device = NULL;
2112	int result;
2113
2114	result = acpi_add_single_object(&device, NULL,
2115					type, ACPI_STA_DEFAULT);
2116	if (result)
2117		return result;
2118
2119	device->flags.match_driver = true;
2120	return device_attach(&device->dev);
2121}
2122EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2123
2124static int acpi_bus_scan_fixed(void)
2125{
2126	int result = 0;
2127
2128	/*
2129	 * Enumerate all fixed-feature devices.
2130	 */
2131	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2132		struct acpi_device *device = NULL;
2133
2134		result = acpi_add_single_object(&device, NULL,
2135						ACPI_BUS_TYPE_POWER_BUTTON,
2136						ACPI_STA_DEFAULT);
2137		if (result)
2138			return result;
2139
2140		device->flags.match_driver = true;
2141		result = device_attach(&device->dev);
2142		if (result < 0)
2143			return result;
2144
2145		device_init_wakeup(&device->dev, true);
2146	}
2147
2148	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2149		struct acpi_device *device = NULL;
2150
2151		result = acpi_add_single_object(&device, NULL,
2152						ACPI_BUS_TYPE_SLEEP_BUTTON,
2153						ACPI_STA_DEFAULT);
2154		if (result)
2155			return result;
2156
2157		device->flags.match_driver = true;
2158		result = device_attach(&device->dev);
2159	}
2160
2161	return result < 0 ? result : 0;
2162}
2163
2164static void __init acpi_get_spcr_uart_addr(void)
2165{
2166	acpi_status status;
2167	struct acpi_table_spcr *spcr_ptr;
2168
2169	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2170				(struct acpi_table_header **)&spcr_ptr);
2171	if (ACPI_FAILURE(status)) {
2172		pr_warn(PREFIX "STAO table present, but SPCR is missing\n");
2173		return;
2174	}
2175
2176	spcr_uart_addr = spcr_ptr->serial_port.address;
2177	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2178}
2179
2180static bool acpi_scan_initialized;
2181
2182int __init acpi_scan_init(void)
2183{
2184	int result;
2185	acpi_status status;
2186	struct acpi_table_stao *stao_ptr;
2187
2188	acpi_pci_root_init();
2189	acpi_pci_link_init();
2190	acpi_processor_init();
2191	acpi_platform_init();
2192	acpi_lpss_init();
2193	acpi_apd_init();
2194	acpi_cmos_rtc_init();
2195	acpi_container_init();
2196	acpi_memory_hotplug_init();
2197	acpi_watchdog_init();
2198	acpi_pnp_init();
2199	acpi_int340x_thermal_init();
2200	acpi_amba_init();
2201	acpi_init_lpit();
2202
2203	acpi_scan_add_handler(&generic_device_handler);
2204
2205	/*
2206	 * If there is STAO table, check whether it needs to ignore the UART
2207	 * device in SPCR table.
2208	 */
2209	status = acpi_get_table(ACPI_SIG_STAO, 0,
2210				(struct acpi_table_header **)&stao_ptr);
2211	if (ACPI_SUCCESS(status)) {
2212		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2213			pr_info(PREFIX "STAO Name List not yet supported.\n");
2214
2215		if (stao_ptr->ignore_uart)
2216			acpi_get_spcr_uart_addr();
2217
2218		acpi_put_table((struct acpi_table_header *)stao_ptr);
2219	}
2220
2221	acpi_gpe_apply_masked_gpes();
2222	acpi_update_all_gpes();
2223
2224	/*
2225	 * Although we call __add_memory() that is documented to require the
2226	 * device_hotplug_lock, it is not necessary here because this is an
2227	 * early code when userspace or any other code path cannot trigger
2228	 * hotplug/hotunplug operations.
2229	 */
2230	mutex_lock(&acpi_scan_lock);
2231	/*
2232	 * Enumerate devices in the ACPI namespace.
2233	 */
2234	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2235	if (result)
2236		goto out;
2237
2238	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2239	if (result)
2240		goto out;
2241
2242	/* Fixed feature devices do not exist on HW-reduced platform */
2243	if (!acpi_gbl_reduced_hardware) {
2244		result = acpi_bus_scan_fixed();
2245		if (result) {
2246			acpi_detach_data(acpi_root->handle,
2247					 acpi_scan_drop_device);
2248			acpi_device_del(acpi_root);
2249			put_device(&acpi_root->dev);
2250			goto out;
2251		}
2252	}
2253
2254	acpi_scan_initialized = true;
2255
2256 out:
2257	mutex_unlock(&acpi_scan_lock);
2258	return result;
2259}
2260
2261static struct acpi_probe_entry *ape;
2262static int acpi_probe_count;
2263static DEFINE_MUTEX(acpi_probe_mutex);
2264
2265static int __init acpi_match_madt(union acpi_subtable_headers *header,
2266				  const unsigned long end)
2267{
2268	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2269		if (!ape->probe_subtbl(header, end))
2270			acpi_probe_count++;
2271
2272	return 0;
2273}
2274
2275int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2276{
2277	int count = 0;
2278
2279	if (acpi_disabled)
2280		return 0;
2281
2282	mutex_lock(&acpi_probe_mutex);
2283	for (ape = ap_head; nr; ape++, nr--) {
2284		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2285			acpi_probe_count = 0;
2286			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2287			count += acpi_probe_count;
2288		} else {
2289			int res;
2290			res = acpi_table_parse(ape->id, ape->probe_table);
2291			if (!res)
2292				count++;
2293		}
2294	}
2295	mutex_unlock(&acpi_probe_mutex);
2296
2297	return count;
2298}
2299
2300struct acpi_table_events_work {
2301	struct work_struct work;
2302	void *table;
2303	u32 event;
2304};
2305
2306static void acpi_table_events_fn(struct work_struct *work)
2307{
2308	struct acpi_table_events_work *tew;
2309
2310	tew = container_of(work, struct acpi_table_events_work, work);
2311
2312	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2313		acpi_scan_lock_acquire();
2314		acpi_bus_scan(ACPI_ROOT_OBJECT);
2315		acpi_scan_lock_release();
2316	}
2317
2318	kfree(tew);
2319}
2320
2321void acpi_scan_table_handler(u32 event, void *table, void *context)
2322{
2323	struct acpi_table_events_work *tew;
2324
2325	if (!acpi_scan_initialized)
2326		return;
2327
2328	if (event != ACPI_TABLE_EVENT_LOAD)
2329		return;
2330
2331	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2332	if (!tew)
2333		return;
2334
2335	INIT_WORK(&tew->work, acpi_table_events_fn);
2336	tew->table = table;
2337	tew->event = event;
2338
2339	schedule_work(&tew->work);
2340}
2341
2342int acpi_reconfig_notifier_register(struct notifier_block *nb)
2343{
2344	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2345}
2346EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2347
2348int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2349{
2350	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2351}
2352EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);