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/signal.h>
  11#include <linux/kthread.h>
  12#include <linux/dmi.h>
  13#include <linux/nls.h>
  14#include <linux/dma-mapping.h>
  15
  16#include <asm/pgtable.h>
  17
  18#include "internal.h"
  19
  20#define _COMPONENT		ACPI_BUS_COMPONENT
  21ACPI_MODULE_NAME("scan");
 
  22extern struct acpi_device *acpi_root;
  23
  24#define ACPI_BUS_CLASS			"system_bus"
  25#define ACPI_BUS_HID			"LNXSYBUS"
  26#define ACPI_BUS_DEVICE_NAME		"System Bus"
  27
  28#define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  29
  30#define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
  31
  32/*
  33 * If set, devices will be hot-removed even if they cannot be put offline
  34 * gracefully (from the kernel's standpoint).
  35 */
  36bool acpi_force_hot_remove;
  37
  38static const char *dummy_hid = "device";
  39
  40static LIST_HEAD(acpi_dep_list);
  41static DEFINE_MUTEX(acpi_dep_list_lock);
  42LIST_HEAD(acpi_bus_id_list);
  43static DEFINE_MUTEX(acpi_scan_lock);
  44static LIST_HEAD(acpi_scan_handlers_list);
  45DEFINE_MUTEX(acpi_device_lock);
  46LIST_HEAD(acpi_wakeup_device_list);
  47static DEFINE_MUTEX(acpi_hp_context_lock);
  48
  49struct acpi_dep_data {
 
 
  50	struct list_head node;
  51	acpi_handle master;
  52	acpi_handle slave;
  53};
  54
  55void acpi_scan_lock_acquire(void)
 
 
 
 
 
 
  56{
  57	mutex_lock(&acpi_scan_lock);
  58}
  59EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  60
  61void acpi_scan_lock_release(void)
  62{
  63	mutex_unlock(&acpi_scan_lock);
  64}
  65EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  66
  67void acpi_lock_hp_context(void)
  68{
  69	mutex_lock(&acpi_hp_context_lock);
  70}
  71
  72void acpi_unlock_hp_context(void)
  73{
  74	mutex_unlock(&acpi_hp_context_lock);
  75}
 
 
 
  76
  77void acpi_initialize_hp_context(struct acpi_device *adev,
  78				struct acpi_hotplug_context *hp,
  79				int (*notify)(struct acpi_device *, u32),
  80				void (*uevent)(struct acpi_device *, u32))
  81{
  82	acpi_lock_hp_context();
  83	hp->notify = notify;
  84	hp->uevent = uevent;
  85	acpi_set_hp_context(adev, hp);
  86	acpi_unlock_hp_context();
  87}
  88EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  89
  90int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  91{
  92	if (!handler)
  93		return -EINVAL;
  94
  95	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  96	return 0;
 
 
 
 
  97}
 
  98
  99int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 100				       const char *hotplug_profile_name)
 101{
 102	int error;
 
 
 
 
 103
 104	error = acpi_scan_add_handler(handler);
 105	if (error)
 106		return error;
 107
 108	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 109	return 0;
 110}
 111
 112bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 113{
 114	struct acpi_device_physical_node *pn;
 115	bool offline = true;
 116
 117	/*
 118	 * acpi_container_offline() calls this for all of the container's
 119	 * children under the container's physical_node_lock lock.
 120	 */
 121	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 122
 123	list_for_each_entry(pn, &adev->physical_node_list, node)
 124		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 125			if (uevent)
 126				kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 127
 128			offline = false;
 129			break;
 130		}
 
 
 
 
 131
 132	mutex_unlock(&adev->physical_node_lock);
 133	return offline;
 134}
 135
 136static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 137				    void **ret_p)
 
 138{
 139	struct acpi_device *device = NULL;
 140	struct acpi_device_physical_node *pn;
 141	bool second_pass = (bool)data;
 142	acpi_status status = AE_OK;
 143
 144	if (acpi_bus_get_device(handle, &device))
 145		return AE_OK;
 146
 147	if (device->handler && !device->handler->hotplug.enabled) {
 148		*ret_p = &device->dev;
 149		return AE_SUPPORT;
 150	}
 151
 152	mutex_lock(&device->physical_node_lock);
 153
 154	list_for_each_entry(pn, &device->physical_node_list, node) {
 155		int ret;
 156
 157		if (second_pass) {
 158			/* Skip devices offlined by the first pass. */
 159			if (pn->put_online)
 160				continue;
 161		} else {
 162			pn->put_online = false;
 163		}
 164		ret = device_offline(pn->dev);
 165		if (acpi_force_hot_remove)
 166			continue;
 167
 168		if (ret >= 0) {
 169			pn->put_online = !ret;
 170		} else {
 171			*ret_p = pn->dev;
 172			if (second_pass) {
 173				status = AE_ERROR;
 174				break;
 175			}
 176		}
 
 
 
 
 177	}
 178
 179	mutex_unlock(&device->physical_node_lock);
 180
 181	return status;
 182}
 183
 184static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 185				   void **ret_p)
 186{
 187	struct acpi_device *device = NULL;
 188	struct acpi_device_physical_node *pn;
 189
 190	if (acpi_bus_get_device(handle, &device))
 191		return AE_OK;
 192
 193	mutex_lock(&device->physical_node_lock);
 194
 195	list_for_each_entry(pn, &device->physical_node_list, node)
 196		if (pn->put_online) {
 197			device_online(pn->dev);
 198			pn->put_online = false;
 199		}
 200
 201	mutex_unlock(&device->physical_node_lock);
 
 
 202
 203	return AE_OK;
 204}
 
 205
 206static int acpi_scan_try_to_offline(struct acpi_device *device)
 207{
 208	acpi_handle handle = device->handle;
 209	struct device *errdev = NULL;
 210	acpi_status status;
 211
 212	/*
 213	 * Carry out two passes here and ignore errors in the first pass,
 214	 * because if the devices in question are memory blocks and
 215	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
 216	 * that the other blocks depend on, but it is not known in advance which
 217	 * block holds them.
 218	 *
 219	 * If the first pass is successful, the second one isn't needed, though.
 220	 */
 221	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 222				     NULL, acpi_bus_offline, (void *)false,
 223				     (void **)&errdev);
 224	if (status == AE_SUPPORT) {
 225		dev_warn(errdev, "Offline disabled.\n");
 226		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 227				    acpi_bus_online, NULL, NULL, NULL);
 228		return -EPERM;
 229	}
 230	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 231	if (errdev) {
 232		errdev = NULL;
 233		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 234				    NULL, acpi_bus_offline, (void *)true,
 235				    (void **)&errdev);
 236		if (!errdev || acpi_force_hot_remove)
 237			acpi_bus_offline(handle, 0, (void *)true,
 238					 (void **)&errdev);
 239
 240		if (errdev && !acpi_force_hot_remove) {
 241			dev_warn(errdev, "Offline failed.\n");
 242			acpi_bus_online(handle, 0, NULL, NULL);
 243			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 244					    ACPI_UINT32_MAX, acpi_bus_online,
 245					    NULL, NULL, NULL);
 246			return -EBUSY;
 247		}
 248	}
 249	return 0;
 250}
 
 251
 252static int acpi_scan_hot_remove(struct acpi_device *device)
 253{
 254	acpi_handle handle = device->handle;
 255	unsigned long long sta;
 256	acpi_status status;
 257
 258	if (device->handler && device->handler->hotplug.demand_offline
 259	    && !acpi_force_hot_remove) {
 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		if (error == -EPERM) {
 410			ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 411			goto err_out;
 412		}
 413	} else {
 414		int (*notify)(struct acpi_device *, u32);
 415
 416		acpi_lock_hp_context();
 417		notify = adev->hp ? adev->hp->notify : NULL;
 418		acpi_unlock_hp_context();
 419		/*
 420		 * There may be additional notify handlers for device objects
 421		 * without the .event() callback, so ignore them here.
 422		 */
 423		if (notify)
 424			error = notify(adev, src);
 425		else
 426			goto out;
 427	}
 428	if (!error)
 429		ost_code = ACPI_OST_SC_SUCCESS;
 430
 431 err_out:
 432	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 
 
 433
 434 out:
 435	acpi_bus_put_acpi_device(adev);
 436	mutex_unlock(&acpi_scan_lock);
 437	unlock_device_hotplug();
 438}
 
 439
 440static void acpi_free_power_resources_lists(struct acpi_device *device)
 441{
 442	int i;
 443
 444	if (device->wakeup.flags.valid)
 445		acpi_power_resources_list_free(&device->wakeup.resources);
 446
 447	if (!device->power.flags.power_resources)
 448		return;
 449
 450	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 451		struct acpi_device_power_state *ps = &device->power.states[i];
 452		acpi_power_resources_list_free(&ps->resources);
 453	}
 454}
 455
 456static void acpi_device_release(struct device *dev)
 457{
 458	struct acpi_device *acpi_dev = to_acpi_device(dev);
 459
 460	acpi_free_properties(acpi_dev);
 461	acpi_free_pnp_ids(&acpi_dev->pnp);
 462	acpi_free_power_resources_lists(acpi_dev);
 463	kfree(acpi_dev);
 464}
 465
 466static void acpi_device_del(struct acpi_device *device)
 467{
 468	struct acpi_device_bus_id *acpi_device_bus_id;
 469
 470	mutex_lock(&acpi_device_lock);
 471	if (device->parent)
 472		list_del(&device->node);
 473
 474	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 475		if (!strcmp(acpi_device_bus_id->bus_id,
 476			    acpi_device_hid(device))) {
 477			if (acpi_device_bus_id->instance_no > 0)
 478				acpi_device_bus_id->instance_no--;
 479			else {
 480				list_del(&acpi_device_bus_id->node);
 481				kfree(acpi_device_bus_id);
 482			}
 483			break;
 484		}
 485
 486	list_del(&device->wakeup_list);
 487	mutex_unlock(&acpi_device_lock);
 
 
 488
 489	acpi_power_add_remove_device(device, false);
 490	acpi_device_remove_files(device);
 491	if (device->remove)
 492		device->remove(device);
 493
 494	device_del(&device->dev);
 
 
 495}
 496
 497static LIST_HEAD(acpi_device_del_list);
 498static DEFINE_MUTEX(acpi_device_del_lock);
 499
 500static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 501{
 502	for (;;) {
 503		struct acpi_device *adev;
 504
 505		mutex_lock(&acpi_device_del_lock);
 
 506
 507		if (list_empty(&acpi_device_del_list)) {
 508			mutex_unlock(&acpi_device_del_lock);
 509			break;
 510		}
 511		adev = list_first_entry(&acpi_device_del_list,
 512					struct acpi_device, del_list);
 513		list_del(&adev->del_list);
 514
 515		mutex_unlock(&acpi_device_del_lock);
 
 516
 517		acpi_device_del(adev);
 518		/*
 519		 * Drop references to all power resources that might have been
 520		 * used by the device.
 521		 */
 522		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 523		put_device(&adev->dev);
 524	}
 525}
 526
 527/**
 528 * acpi_scan_drop_device - Drop an ACPI device object.
 529 * @handle: Handle of an ACPI namespace node, not used.
 530 * @context: Address of the ACPI device object to drop.
 531 *
 532 * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 533 * namespace node the device object pointed to by @context is attached to.
 534 *
 535 * The unregistration is carried out asynchronously to avoid running
 536 * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 537 * ensure the correct ordering (the device objects must be unregistered in the
 538 * same order in which the corresponding namespace nodes are deleted).
 539 */
 540static void acpi_scan_drop_device(acpi_handle handle, void *context)
 541{
 542	static DECLARE_WORK(work, acpi_device_del_work_fn);
 543	struct acpi_device *adev = context;
 544
 545	mutex_lock(&acpi_device_del_lock);
 546
 547	/*
 548	 * Use the ACPI hotplug workqueue which is ordered, so this work item
 549	 * won't run after any hotplug work items submitted subsequently.  That
 550	 * prevents attempts to register device objects identical to those being
 551	 * deleted from happening concurrently (such attempts result from
 552	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
 553	 * run after all of the work items submitted previosuly, which helps
 554	 * those work items to ensure that they are not accessing stale device
 555	 * objects.
 556	 */
 557	if (list_empty(&acpi_device_del_list))
 558		acpi_queue_hotplug_work(&work);
 559
 560	list_add_tail(&adev->del_list, &acpi_device_del_list);
 561	/* Make acpi_ns_validate_handle() return NULL for this handle. */
 562	adev->handle = INVALID_ACPI_HANDLE;
 563
 564	mutex_unlock(&acpi_device_del_lock);
 
 
 565}
 566
 567static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 568				void (*callback)(void *))
 569{
 570	acpi_status status;
 571
 572	if (!device)
 573		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 574
 575	status = acpi_get_data_full(handle, acpi_scan_drop_device,
 576				    (void **)device, callback);
 577	if (ACPI_FAILURE(status) || !*device) {
 578		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 579				  handle));
 580		return -ENODEV;
 581	}
 582	return 0;
 583}
 584
 585int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 586{
 587	return acpi_get_device_data(handle, device, NULL);
 
 
 
 
 
 
 
 
 588}
 589EXPORT_SYMBOL(acpi_bus_get_device);
 590
 591static void get_acpi_device(void *dev)
 
 
 592{
 593	if (dev)
 594		get_device(&((struct acpi_device *)dev)->dev);
 595}
 596
 597struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 598{
 599	struct acpi_device *adev = NULL;
 
 
 
 
 
 
 
 
 
 
 
 600
 601	acpi_get_device_data(handle, &adev, get_acpi_device);
 602	return adev;
 
 
 
 
 603}
 604
 605void acpi_bus_put_acpi_device(struct acpi_device *adev)
 606{
 607	put_device(&adev->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 608}
 609
 610int acpi_device_add(struct acpi_device *device,
 611		    void (*release)(struct device *))
 
 
 
 
 
 
 
 
 
 612{
 613	int result;
 614	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 615	int found = 0;
 616
 617	if (device->handle) {
 618		acpi_status status;
 619
 620		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 621					  device);
 622		if (ACPI_FAILURE(status)) {
 623			acpi_handle_err(device->handle,
 624					"Unable to attach device data\n");
 625			return -ENODEV;
 626		}
 627	}
 628
 629	/*
 630	 * Linkage
 631	 * -------
 632	 * Link this device to its parent and siblings.
 633	 */
 634	INIT_LIST_HEAD(&device->children);
 635	INIT_LIST_HEAD(&device->node);
 636	INIT_LIST_HEAD(&device->wakeup_list);
 637	INIT_LIST_HEAD(&device->physical_node_list);
 638	INIT_LIST_HEAD(&device->del_list);
 639	mutex_init(&device->physical_node_lock);
 640
 641	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 642	if (!new_bus_id) {
 643		pr_err(PREFIX "Memory allocation error\n");
 644		result = -ENOMEM;
 645		goto err_detach;
 646	}
 647
 648	mutex_lock(&acpi_device_lock);
 649	/*
 650	 * Find suitable bus_id and instance number in acpi_bus_id_list
 651	 * If failed, create one and link it into acpi_bus_id_list
 652	 */
 653	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 654		if (!strcmp(acpi_device_bus_id->bus_id,
 655			    acpi_device_hid(device))) {
 656			acpi_device_bus_id->instance_no++;
 657			found = 1;
 658			kfree(new_bus_id);
 659			break;
 660		}
 661	}
 662	if (!found) {
 663		acpi_device_bus_id = new_bus_id;
 664		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 665		acpi_device_bus_id->instance_no = 0;
 666		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 667	}
 668	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 669
 670	if (device->parent)
 671		list_add_tail(&device->node, &device->parent->children);
 672
 673	if (device->wakeup.flags.valid)
 674		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 675	mutex_unlock(&acpi_device_lock);
 676
 677	if (device->parent)
 678		device->dev.parent = &device->parent->dev;
 679	device->dev.bus = &acpi_bus_type;
 680	device->dev.release = release;
 681	result = device_add(&device->dev);
 682	if (result) {
 683		dev_err(&device->dev, "Error registering device\n");
 684		goto err;
 685	}
 686
 687	result = acpi_device_setup_files(device);
 688	if (result)
 689		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 690		       dev_name(&device->dev));
 691
 
 692	return 0;
 
 
 
 
 
 
 
 
 693
 694 err:
 
 695	mutex_lock(&acpi_device_lock);
 696	if (device->parent)
 697		list_del(&device->node);
 
 698	list_del(&device->wakeup_list);
 699	mutex_unlock(&acpi_device_lock);
 700
 701 err_detach:
 702	acpi_detach_data(device->handle, acpi_scan_drop_device);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 703	return result;
 704}
 705
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 706/* --------------------------------------------------------------------------
 707                                 Device Enumeration
 708   -------------------------------------------------------------------------- */
 709static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 710{
 711	struct acpi_device *device = NULL;
 712	acpi_status status;
 
 
 713
 714	/*
 715	 * Fixed hardware devices do not appear in the namespace and do not
 716	 * have handles, but we fabricate acpi_devices for them, so we have
 717	 * to deal with them specially.
 718	 */
 719	if (!handle)
 720		return acpi_root;
 721
 722	do {
 723		status = acpi_get_parent(handle, &handle);
 
 
 724		if (ACPI_FAILURE(status))
 725			return status == AE_NULL_ENTRY ? NULL : acpi_root;
 726	} while (acpi_bus_get_device(handle, &device));
 727	return device;
 
 
 
 728}
 729
 730acpi_status
 731acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 732{
 733	acpi_status status;
 734	acpi_handle tmp;
 735	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 736	union acpi_object *obj;
 737
 738	status = acpi_get_handle(handle, "_EJD", &tmp);
 739	if (ACPI_FAILURE(status))
 740		return status;
 741
 742	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 743	if (ACPI_SUCCESS(status)) {
 744		obj = buffer.pointer;
 745		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 746					 ejd);
 747		kfree(buffer.pointer);
 748	}
 749	return status;
 750}
 751EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 752
 753static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 754					struct acpi_device_wakeup *wakeup)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 755{
 756	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 757	union acpi_object *package = NULL;
 758	union acpi_object *element = NULL;
 759	acpi_status status;
 760	int err = -ENODATA;
 761
 762	if (!wakeup)
 763		return -EINVAL;
 764
 765	INIT_LIST_HEAD(&wakeup->resources);
 766
 767	/* _PRW */
 768	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 769	if (ACPI_FAILURE(status)) {
 770		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 771		return err;
 772	}
 773
 774	package = (union acpi_object *)buffer.pointer;
 775
 776	if (!package || package->package.count < 2)
 
 777		goto out;
 
 778
 779	element = &(package->package.elements[0]);
 780	if (!element)
 
 781		goto out;
 782
 783	if (element->type == ACPI_TYPE_PACKAGE) {
 784		if ((element->package.count < 2) ||
 785		    (element->package.elements[0].type !=
 786		     ACPI_TYPE_LOCAL_REFERENCE)
 787		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 
 788			goto out;
 789
 790		wakeup->gpe_device =
 791		    element->package.elements[0].reference.handle;
 792		wakeup->gpe_number =
 793		    (u32) element->package.elements[1].integer.value;
 794	} else if (element->type == ACPI_TYPE_INTEGER) {
 795		wakeup->gpe_device = NULL;
 796		wakeup->gpe_number = element->integer.value;
 797	} else {
 
 798		goto out;
 799	}
 800
 801	element = &(package->package.elements[1]);
 802	if (element->type != ACPI_TYPE_INTEGER)
 
 803		goto out;
 804
 805	wakeup->sleep_state = element->integer.value;
 806
 807	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 808	if (err)
 809		goto out;
 810
 811	if (!list_empty(&wakeup->resources)) {
 812		int sleep_state;
 813
 814		err = acpi_power_wakeup_list_init(&wakeup->resources,
 815						  &sleep_state);
 816		if (err) {
 817			acpi_handle_warn(handle, "Retrieving current states "
 818					 "of wakeup power resources failed\n");
 819			acpi_power_resources_list_free(&wakeup->resources);
 820			goto out;
 821		}
 822		if (sleep_state < wakeup->sleep_state) {
 823			acpi_handle_warn(handle, "Overriding _PRW sleep state "
 824					 "(S%d) by S%d from power resources\n",
 825					 (int)wakeup->sleep_state, sleep_state);
 826			wakeup->sleep_state = sleep_state;
 827		}
 828	}
 829
 
 
 830 out:
 831	kfree(buffer.pointer);
 832	return err;
 
 833}
 834
 835static void acpi_wakeup_gpe_init(struct acpi_device *device)
 836{
 837	static const struct acpi_device_id button_device_ids[] = {
 838		{"PNP0C0C", 0},
 839		{"PNP0C0D", 0},
 
 840		{"PNP0C0E", 0},
 841		{"", 0},
 842	};
 843	struct acpi_device_wakeup *wakeup = &device->wakeup;
 844	acpi_status status;
 845	acpi_event_status event_status;
 846
 847	wakeup->flags.notifier_present = 0;
 848
 849	/* Power button, Lid switch always enable wakeup */
 850	if (!acpi_match_device_ids(device, button_device_ids)) {
 851		wakeup->flags.run_wake = 1;
 852		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 853			/* Do not use Lid/sleep button for S5 wakeup */
 854			if (wakeup->sleep_state == ACPI_STATE_S5)
 855				wakeup->sleep_state = ACPI_STATE_S4;
 856		}
 857		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 858		device_set_wakeup_capable(&device->dev, true);
 859		return;
 860	}
 861
 862	acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 863				wakeup->gpe_number);
 864	status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
 865				     &event_status);
 866	if (ACPI_FAILURE(status))
 867		return;
 868
 869	wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
 870}
 871
 872static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 873{
 874	int err;
 
 
 875
 876	/* Presence of _PRW indicates wake capable */
 877	if (!acpi_has_method(device->handle, "_PRW"))
 
 878		return;
 879
 880	err = acpi_bus_extract_wakeup_device_power_package(device->handle,
 881							   &device->wakeup);
 882	if (err) {
 883		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 884		return;
 885	}
 886
 887	device->wakeup.flags.valid = 1;
 888	device->wakeup.prepare_count = 0;
 889	acpi_wakeup_gpe_init(device);
 890	/* Call _PSW/_DSW object to disable its ability to wake the sleeping
 891	 * system for the ACPI device with the _PRW object.
 892	 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 893	 * So it is necessary to call _DSW object first. Only when it is not
 894	 * present will the _PSW object used.
 895	 */
 896	err = acpi_device_sleep_wake(device, 0, 0, 0);
 897	if (err)
 898		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 899				"error in _DSW or _PSW evaluation\n"));
 900}
 901
 902static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 903{
 904	struct acpi_device_power_state *ps = &device->power.states[state];
 905	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 906	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 907	acpi_status status;
 908
 909	INIT_LIST_HEAD(&ps->resources);
 910
 911	/* Evaluate "_PRx" to get referenced power resources */
 912	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 913	if (ACPI_SUCCESS(status)) {
 914		union acpi_object *package = buffer.pointer;
 915
 916		if (buffer.length && package
 917		    && package->type == ACPI_TYPE_PACKAGE
 918		    && package->package.count) {
 919			int err = acpi_extract_power_resources(package, 0,
 920							       &ps->resources);
 921			if (!err)
 922				device->power.flags.power_resources = 1;
 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	if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 971		device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 972
 973	/* Set defaults for D0 and D3hot states (always valid) */
 
 
 
 
 
 
 
 
 
 
 
 
 974	device->power.states[ACPI_STATE_D0].flags.valid = 1;
 975	device->power.states[ACPI_STATE_D0].power = 100;
 976	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 
 
 
 
 
 
 
 977
 978	if (acpi_bus_init_power(device))
 979		device->flags.power_manageable = 0;
 980}
 981
 982static void acpi_bus_get_flags(struct acpi_device *device)
 983{
 
 
 
 
 984	/* Presence of _STA indicates 'dynamic_status' */
 985	if (acpi_has_method(device->handle, "_STA"))
 
 986		device->flags.dynamic_status = 1;
 987
 988	/* Presence of _RMV indicates 'removable' */
 989	if (acpi_has_method(device->handle, "_RMV"))
 
 990		device->flags.removable = 1;
 991
 992	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
 993	if (acpi_has_method(device->handle, "_EJD") ||
 994	    acpi_has_method(device->handle, "_EJ0"))
 995		device->flags.ejectable = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 996}
 997
 998static void acpi_device_get_busid(struct acpi_device *device)
 999{
1000	char bus_id[5] = { '?', 0 };
1001	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1002	int i = 0;
1003
1004	/*
1005	 * Bus ID
1006	 * ------
1007	 * The device's Bus ID is simply the object name.
1008	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1009	 */
1010	if (ACPI_IS_ROOT_DEVICE(device)) {
1011		strcpy(device->pnp.bus_id, "ACPI");
1012		return;
1013	}
1014
1015	switch (device->device_type) {
1016	case ACPI_BUS_TYPE_POWER_BUTTON:
1017		strcpy(device->pnp.bus_id, "PWRF");
1018		break;
1019	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1020		strcpy(device->pnp.bus_id, "SLPF");
1021		break;
1022	default:
1023		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1024		/* Clean up trailing underscores (if any) */
1025		for (i = 3; i > 1; i--) {
1026			if (bus_id[i] == '_')
1027				bus_id[i] = '\0';
1028			else
1029				break;
1030		}
1031		strcpy(device->pnp.bus_id, bus_id);
1032		break;
1033	}
1034}
1035
1036/*
1037 * acpi_ata_match - see if an acpi object is an ATA device
1038 *
1039 * If an acpi object has one of the ACPI ATA methods defined,
1040 * then we can safely call it an ATA device.
1041 */
1042bool acpi_ata_match(acpi_handle handle)
1043{
1044	return acpi_has_method(handle, "_GTF") ||
1045	       acpi_has_method(handle, "_GTM") ||
1046	       acpi_has_method(handle, "_STM") ||
1047	       acpi_has_method(handle, "_SDD");
1048}
1049
1050/*
1051 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1052 *
1053 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1054 * then we can safely call it an ejectable drive bay
1055 */
1056bool acpi_bay_match(acpi_handle handle)
1057{
 
 
1058	acpi_handle phandle;
1059
1060	if (!acpi_has_method(handle, "_EJ0"))
1061		return false;
1062	if (acpi_ata_match(handle))
1063		return true;
1064	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1065		return false;
1066
1067	return acpi_ata_match(phandle);
1068}
1069
1070bool acpi_device_is_battery(struct acpi_device *adev)
1071{
1072	struct acpi_hardware_id *hwid;
1073
1074	list_for_each_entry(hwid, &adev->pnp.ids, list)
1075		if (!strcmp("PNP0C0A", hwid->id))
1076			return true;
1077
1078	return false;
1079}
 
 
 
1080
1081static bool is_ejectable_bay(struct acpi_device *adev)
1082{
1083	acpi_handle handle = adev->handle;
1084
1085	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1086		return true;
 
 
 
1087
1088	return acpi_bay_match(handle);
1089}
1090
1091/*
1092 * acpi_dock_match - see if an acpi object has a _DCK method
1093 */
1094bool acpi_dock_match(acpi_handle handle)
1095{
1096	return acpi_has_method(handle, "_DCK");
1097}
1098
1099static acpi_status
1100acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1101			  void **return_value)
1102{
1103	long *cap = context;
1104
1105	if (acpi_has_method(handle, "_BCM") &&
1106	    acpi_has_method(handle, "_BCL")) {
1107		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1108				  "support\n"));
1109		*cap |= ACPI_VIDEO_BACKLIGHT;
1110		if (!acpi_has_method(handle, "_BQC"))
1111			printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
1112				"cannot determine initial brightness\n");
1113		/* We have backlight support, no need to scan further */
1114		return AE_CTRL_TERMINATE;
1115	}
1116	return 0;
1117}
1118
1119/* Returns true if the ACPI object is a video device which can be
1120 * handled by video.ko.
1121 * The device will get a Linux specific CID added in scan.c to
1122 * identify the device as an ACPI graphics device
1123 * Be aware that the graphics device may not be physically present
1124 * Use acpi_video_get_capabilities() to detect general ACPI video
1125 * capabilities of present cards
1126 */
1127long acpi_is_video_device(acpi_handle handle)
1128{
1129	long video_caps = 0;
1130
1131	/* Is this device able to support video switching ? */
1132	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1133		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1134
1135	/* Is this device able to retrieve a video ROM ? */
1136	if (acpi_has_method(handle, "_ROM"))
1137		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1138
1139	/* Is this device able to configure which video head to be POSTed ? */
1140	if (acpi_has_method(handle, "_VPO") &&
1141	    acpi_has_method(handle, "_GPD") &&
1142	    acpi_has_method(handle, "_SPD"))
1143		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1144
1145	/* Only check for backlight functionality if one of the above hit. */
1146	if (video_caps)
1147		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1148				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1149				    &video_caps, NULL);
1150
1151	return video_caps;
1152}
1153EXPORT_SYMBOL(acpi_is_video_device);
1154
1155const char *acpi_device_hid(struct acpi_device *device)
1156{
1157	struct acpi_hardware_id *hid;
1158
1159	if (list_empty(&device->pnp.ids))
1160		return dummy_hid;
1161
1162	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1163	return hid->id;
1164}
1165EXPORT_SYMBOL(acpi_device_hid);
1166
1167static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1168{
1169	struct acpi_hardware_id *id;
1170
1171	id = kmalloc(sizeof(*id), GFP_KERNEL);
1172	if (!id)
1173		return;
1174
1175	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1176	if (!id->id) {
1177		kfree(id);
1178		return;
1179	}
1180
1181	list_add_tail(&id->list, &pnp->ids);
1182	pnp->type.hardware_id = 1;
1183}
1184
1185/*
1186 * Old IBM workstations have a DSDT bug wherein the SMBus object
1187 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1188 * prefix.  Work around this.
1189 */
1190static bool acpi_ibm_smbus_match(acpi_handle handle)
1191{
1192	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1193	struct acpi_buffer path = { sizeof(node_name), node_name };
 
1194
1195	if (!dmi_name_in_vendors("IBM"))
1196		return false;
1197
1198	/* Look for SMBS object */
1199	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1200	    strcmp("SMBS", path.pointer))
1201		return false;
1202
1203	/* Does it have the necessary (but misnamed) methods? */
1204	if (acpi_has_method(handle, "SBI") &&
1205	    acpi_has_method(handle, "SBR") &&
1206	    acpi_has_method(handle, "SBW"))
1207		return true;
1208
1209	return false;
1210}
1211
1212static bool acpi_object_is_system_bus(acpi_handle handle)
1213{
1214	acpi_handle tmp;
1215
1216	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1217	    tmp == handle)
1218		return true;
1219	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1220	    tmp == handle)
1221		return true;
1222
1223	return false;
 
 
 
 
 
 
 
 
1224}
1225
1226static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1227				int device_type)
1228{
1229	acpi_status status;
1230	struct acpi_device_info *info;
1231	struct acpi_pnp_device_id_list *cid_list;
1232	int i;
1233
1234	switch (device_type) {
1235	case ACPI_BUS_TYPE_DEVICE:
1236		if (handle == ACPI_ROOT_OBJECT) {
1237			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1238			break;
1239		}
1240
1241		status = acpi_get_object_info(handle, &info);
1242		if (ACPI_FAILURE(status)) {
1243			pr_err(PREFIX "%s: Error reading device info\n",
1244					__func__);
1245			return;
1246		}
1247
1248		if (info->valid & ACPI_VALID_HID) {
1249			acpi_add_id(pnp, info->hardware_id.string);
1250			pnp->type.platform_id = 1;
1251		}
1252		if (info->valid & ACPI_VALID_CID) {
1253			cid_list = &info->compatible_id_list;
1254			for (i = 0; i < cid_list->count; i++)
1255				acpi_add_id(pnp, cid_list->ids[i].string);
1256		}
1257		if (info->valid & ACPI_VALID_ADR) {
1258			pnp->bus_address = info->address;
1259			pnp->type.bus_address = 1;
1260		}
1261		if (info->valid & ACPI_VALID_UID)
1262			pnp->unique_id = kstrdup(info->unique_id.string,
1263							GFP_KERNEL);
1264		if (info->valid & ACPI_VALID_CLS)
1265			acpi_add_id(pnp, info->class_code.string);
1266
1267		kfree(info);
1268
1269		/*
1270		 * Some devices don't reliably have _HIDs & _CIDs, so add
1271		 * synthetic HIDs to make sure drivers can find them.
1272		 */
1273		if (acpi_is_video_device(handle))
1274			acpi_add_id(pnp, ACPI_VIDEO_HID);
1275		else if (acpi_bay_match(handle))
1276			acpi_add_id(pnp, ACPI_BAY_HID);
1277		else if (acpi_dock_match(handle))
1278			acpi_add_id(pnp, ACPI_DOCK_HID);
1279		else if (acpi_ibm_smbus_match(handle))
1280			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1281		else if (list_empty(&pnp->ids) &&
1282			 acpi_object_is_system_bus(handle)) {
1283			/* \_SB, \_TZ, LNXSYBUS */
1284			acpi_add_id(pnp, ACPI_BUS_HID);
1285			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1286			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1287		}
1288
1289		break;
1290	case ACPI_BUS_TYPE_POWER:
1291		acpi_add_id(pnp, ACPI_POWER_HID);
1292		break;
1293	case ACPI_BUS_TYPE_PROCESSOR:
1294		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1295		break;
1296	case ACPI_BUS_TYPE_THERMAL:
1297		acpi_add_id(pnp, ACPI_THERMAL_HID);
1298		break;
1299	case ACPI_BUS_TYPE_POWER_BUTTON:
1300		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1301		break;
1302	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1303		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1304		break;
1305	}
1306}
1307
1308void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1309{
1310	struct acpi_hardware_id *id, *tmp;
1311
1312	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1313		kfree_const(id->id);
1314		kfree(id);
1315	}
1316	kfree(pnp->unique_id);
1317}
1318
1319/**
1320 * acpi_dma_supported - Check DMA support for the specified device.
1321 * @adev: The pointer to acpi device
1322 *
1323 * Return false if DMA is not supported. Otherwise, return true
1324 */
1325bool acpi_dma_supported(struct acpi_device *adev)
1326{
1327	if (!adev)
1328		return false;
1329
1330	if (adev->flags.cca_seen)
1331		return true;
1332
1333	/*
1334	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1335	* DMA on "Intel platforms".  Presumably that includes all x86 and
1336	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1337	*/
1338	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1339		return true;
1340
1341	return false;
1342}
1343
1344/**
1345 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1346 * @adev: The pointer to acpi device
1347 *
1348 * Return enum dev_dma_attr.
1349 */
1350enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1351{
1352	if (!acpi_dma_supported(adev))
1353		return DEV_DMA_NOT_SUPPORTED;
1354
1355	if (adev->flags.coherent_dma)
1356		return DEV_DMA_COHERENT;
1357	else
1358		return DEV_DMA_NON_COHERENT;
1359}
1360
1361static void acpi_init_coherency(struct acpi_device *adev)
1362{
1363	unsigned long long cca = 0;
1364	acpi_status status;
1365	struct acpi_device *parent = adev->parent;
1366
1367	if (parent && parent->flags.cca_seen) {
1368		/*
1369		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1370		 * already saw one.
1371		 */
1372		adev->flags.cca_seen = 1;
1373		cca = parent->flags.coherent_dma;
1374	} else {
1375		status = acpi_evaluate_integer(adev->handle, "_CCA",
1376					       NULL, &cca);
1377		if (ACPI_SUCCESS(status))
1378			adev->flags.cca_seen = 1;
1379		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1380			/*
1381			 * If architecture does not specify that _CCA is
1382			 * required for DMA-able devices (e.g. x86),
1383			 * we default to _CCA=1.
1384			 */
1385			cca = 1;
1386		else
1387			acpi_handle_debug(adev->handle,
1388					  "ACPI device is missing _CCA.\n");
1389	}
1390
1391	adev->flags.coherent_dma = cca;
1392}
1393
1394void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1395			     int type, unsigned long long sta)
1396{
1397	INIT_LIST_HEAD(&device->pnp.ids);
1398	device->device_type = type;
1399	device->handle = handle;
1400	device->parent = acpi_bus_get_parent(handle);
1401	device->fwnode.type = FWNODE_ACPI;
1402	acpi_set_device_status(device, sta);
1403	acpi_device_get_busid(device);
1404	acpi_set_pnp_ids(handle, &device->pnp, type);
1405	acpi_init_properties(device);
1406	acpi_bus_get_flags(device);
1407	device->flags.match_driver = false;
1408	device->flags.initialized = true;
1409	device->flags.visited = false;
1410	device_initialize(&device->dev);
1411	dev_set_uevent_suppress(&device->dev, true);
1412	acpi_init_coherency(device);
1413}
1414
1415void acpi_device_add_finalize(struct acpi_device *device)
1416{
1417	dev_set_uevent_suppress(&device->dev, false);
1418	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1419}
1420
1421static int acpi_add_single_object(struct acpi_device **child,
1422				  acpi_handle handle, int type,
1423				  unsigned long long sta)
 
1424{
1425	int result;
1426	struct acpi_device *device;
1427	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1428
1429	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1430	if (!device) {
1431		printk(KERN_ERR PREFIX "Memory allocation error\n");
1432		return -ENOMEM;
1433	}
1434
1435	acpi_init_device_object(device, handle, type, sta);
1436	acpi_bus_get_power_flags(device);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1437	acpi_bus_get_wakeup_device_flags(device);
1438
1439	result = acpi_device_add(device, acpi_device_release);
1440	if (result) {
1441		acpi_device_release(&device->dev);
1442		return result;
 
 
 
 
1443	}
1444
1445	acpi_power_add_remove_device(device, true);
1446	acpi_device_add_finalize(device);
1447	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1448	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1449		dev_name(&device->dev), (char *) buffer.pointer,
1450		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1451	kfree(buffer.pointer);
1452	*child = device;
1453	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1454}
1455
1456static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1457				    unsigned long long *sta)
1458{
1459	acpi_status status;
1460	acpi_object_type acpi_type;
1461
1462	status = acpi_get_type(handle, &acpi_type);
1463	if (ACPI_FAILURE(status))
1464		return -ENODEV;
1465
1466	switch (acpi_type) {
1467	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1468	case ACPI_TYPE_DEVICE:
1469		*type = ACPI_BUS_TYPE_DEVICE;
1470		status = acpi_bus_get_status_handle(handle, sta);
1471		if (ACPI_FAILURE(status))
1472			*sta = 0;
1473		break;
1474	case ACPI_TYPE_PROCESSOR:
1475		*type = ACPI_BUS_TYPE_PROCESSOR;
1476		status = acpi_bus_get_status_handle(handle, sta);
1477		if (ACPI_FAILURE(status))
1478			return -ENODEV;
1479		break;
1480	case ACPI_TYPE_THERMAL:
1481		*type = ACPI_BUS_TYPE_THERMAL;
1482		*sta = ACPI_STA_DEFAULT;
1483		break;
1484	case ACPI_TYPE_POWER:
1485		*type = ACPI_BUS_TYPE_POWER;
1486		*sta = ACPI_STA_DEFAULT;
1487		break;
1488	default:
1489		return -ENODEV;
1490	}
1491
1492	return 0;
1493}
1494
1495bool acpi_device_is_present(struct acpi_device *adev)
1496{
1497	if (adev->status.present || adev->status.functional)
1498		return true;
1499
1500	adev->flags.initialized = false;
1501	return false;
1502}
1503
1504static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1505				       const char *idstr,
1506				       const struct acpi_device_id **matchid)
1507{
1508	const struct acpi_device_id *devid;
1509
1510	if (handler->match)
1511		return handler->match(idstr, matchid);
1512
1513	for (devid = handler->ids; devid->id[0]; devid++)
1514		if (!strcmp((char *)devid->id, idstr)) {
1515			if (matchid)
1516				*matchid = devid;
1517
1518			return true;
1519		}
1520
1521	return false;
1522}
1523
1524static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1525					const struct acpi_device_id **matchid)
1526{
1527	struct acpi_scan_handler *handler;
1528
1529	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1530		if (acpi_scan_handler_matching(handler, idstr, matchid))
1531			return handler;
1532
1533	return NULL;
1534}
1535
1536void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1537{
1538	if (!!hotplug->enabled == !!val)
1539		return;
1540
1541	mutex_lock(&acpi_scan_lock);
1542
1543	hotplug->enabled = val;
1544
1545	mutex_unlock(&acpi_scan_lock);
1546}
1547
1548static void acpi_scan_init_hotplug(struct acpi_device *adev)
1549{
1550	struct acpi_hardware_id *hwid;
1551
1552	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1553		acpi_dock_add(adev);
1554		return;
1555	}
1556	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1557		struct acpi_scan_handler *handler;
1558
1559		handler = acpi_scan_match_handler(hwid->id, NULL);
1560		if (handler) {
1561			adev->flags.hotplug_notify = true;
1562			break;
1563		}
1564	}
1565}
1566
1567static void acpi_device_dep_initialize(struct acpi_device *adev)
1568{
1569	struct acpi_dep_data *dep;
1570	struct acpi_handle_list dep_devices;
1571	acpi_status status;
1572	int i;
1573
1574	if (!acpi_has_method(adev->handle, "_DEP"))
1575		return;
1576
1577	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1578					&dep_devices);
1579	if (ACPI_FAILURE(status)) {
1580		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1581		return;
1582	}
1583
1584	for (i = 0; i < dep_devices.count; i++) {
1585		struct acpi_device_info *info;
1586		int skip;
1587
1588		status = acpi_get_object_info(dep_devices.handles[i], &info);
1589		if (ACPI_FAILURE(status)) {
1590			dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1591			continue;
1592		}
1593
1594		/*
1595		 * Skip the dependency of Windows System Power
1596		 * Management Controller
1597		 */
1598		skip = info->valid & ACPI_VALID_HID &&
1599			!strcmp(info->hardware_id.string, "INT3396");
1600
1601		kfree(info);
1602
1603		if (skip)
1604			continue;
1605
1606		dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1607		if (!dep)
1608			return;
1609
1610		dep->master = dep_devices.handles[i];
1611		dep->slave  = adev->handle;
1612		adev->dep_unmet++;
1613
1614		mutex_lock(&acpi_dep_list_lock);
1615		list_add_tail(&dep->node , &acpi_dep_list);
1616		mutex_unlock(&acpi_dep_list_lock);
1617	}
1618}
1619
1620static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1621				      void *not_used, void **return_value)
1622{
1623	struct acpi_device *device = NULL;
1624	int type;
1625	unsigned long long sta;
 
 
1626	int result;
1627
1628	acpi_bus_get_device(handle, &device);
1629	if (device)
1630		goto out;
1631
1632	result = acpi_bus_type_and_status(handle, &type, &sta);
1633	if (result)
1634		return AE_OK;
1635
1636	if (type == ACPI_BUS_TYPE_POWER) {
1637		acpi_add_power_resource(handle);
1638		return AE_OK;
 
 
 
 
 
 
 
1639	}
1640
1641	acpi_add_single_object(&device, handle, type, sta);
 
 
 
 
 
 
 
 
1642	if (!device)
1643		return AE_CTRL_DEPTH;
1644
1645	acpi_scan_init_hotplug(device);
1646	acpi_device_dep_initialize(device);
 
 
 
1647
1648 out:
1649	if (!*return_value)
1650		*return_value = device;
1651
1652	return AE_OK;
1653}
1654
1655static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
 
1656{
1657	bool *is_spi_i2c_slave_p = data;
1658
1659	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1660		return 1;
1661
1662	/*
1663	 * devices that are connected to UART still need to be enumerated to
1664	 * platform bus
1665	 */
1666	if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1667		*is_spi_i2c_slave_p = true;
1668
1669	 /* no need to do more checking */
1670	return -1;
1671}
1672
1673static void acpi_default_enumeration(struct acpi_device *device)
1674{
1675	struct list_head resource_list;
1676	bool is_spi_i2c_slave = false;
1677
1678	/*
1679	 * Do not enemerate SPI/I2C slaves as they will be enuerated by their
1680	 * respective parents.
1681	 */
1682	INIT_LIST_HEAD(&resource_list);
1683	acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1684			       &is_spi_i2c_slave);
1685	acpi_dev_free_resource_list(&resource_list);
1686	if (!is_spi_i2c_slave)
1687		acpi_create_platform_device(device);
1688}
1689
1690static const struct acpi_device_id generic_device_ids[] = {
1691	{ACPI_DT_NAMESPACE_HID, },
1692	{"", },
1693};
1694
1695static int acpi_generic_device_attach(struct acpi_device *adev,
1696				      const struct acpi_device_id *not_used)
1697{
1698	/*
1699	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1700	 * below can be unconditional.
1701	 */
1702	if (adev->data.of_compatible)
1703		acpi_default_enumeration(adev);
1704
1705	return 1;
 
 
 
1706}
1707
1708static struct acpi_scan_handler generic_device_handler = {
1709	.ids = generic_device_ids,
1710	.attach = acpi_generic_device_attach,
1711};
 
 
 
 
 
 
 
1712
1713static int acpi_scan_attach_handler(struct acpi_device *device)
 
 
1714{
1715	struct acpi_hardware_id *hwid;
1716	int ret = 0;
1717
1718	list_for_each_entry(hwid, &device->pnp.ids, list) {
1719		const struct acpi_device_id *devid;
1720		struct acpi_scan_handler *handler;
1721
1722		handler = acpi_scan_match_handler(hwid->id, &devid);
1723		if (handler) {
1724			if (!handler->attach) {
1725				device->pnp.type.platform_id = 0;
1726				continue;
1727			}
1728			device->handler = handler;
1729			ret = handler->attach(device, devid);
1730			if (ret > 0)
1731				break;
1732
1733			device->handler = NULL;
1734			if (ret < 0)
1735				break;
1736		}
1737	}
1738
1739	return ret;
1740}
 
1741
1742static void acpi_bus_attach(struct acpi_device *device)
1743{
1744	struct acpi_device *child;
1745	acpi_handle ejd;
1746	int ret;
1747
1748	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1749		register_dock_dependent_device(device, ejd);
1750
1751	acpi_bus_get_status(device);
1752	/* Skip devices that are not present. */
1753	if (!acpi_device_is_present(device)) {
1754		device->flags.visited = false;
1755		device->flags.power_manageable = 0;
1756		return;
1757	}
1758	if (device->handler)
1759		goto ok;
1760
1761	if (!device->flags.initialized) {
1762		device->flags.power_manageable =
1763			device->power.states[ACPI_STATE_D0].flags.valid;
1764		if (acpi_bus_init_power(device))
1765			device->flags.power_manageable = 0;
1766
1767		device->flags.initialized = true;
1768	}
1769	device->flags.visited = false;
1770	ret = acpi_scan_attach_handler(device);
1771	if (ret < 0)
1772		return;
1773
1774	device->flags.match_driver = true;
1775	if (!ret) {
1776		ret = device_attach(&device->dev);
1777		if (ret < 0)
1778			return;
1779
1780		if (!ret && device->pnp.type.platform_id)
1781			acpi_default_enumeration(device);
1782	}
1783	device->flags.visited = true;
1784
1785 ok:
1786	list_for_each_entry(child, &device->children, node)
1787		acpi_bus_attach(child);
1788
1789	if (device->handler && device->handler->hotplug.notify_online)
1790		device->handler->hotplug.notify_online(device);
1791}
 
1792
1793void acpi_walk_dep_device_list(acpi_handle handle)
1794{
1795	struct acpi_dep_data *dep, *tmp;
1796	struct acpi_device *adev;
1797
1798	mutex_lock(&acpi_dep_list_lock);
1799	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1800		if (dep->master == handle) {
1801			acpi_bus_get_device(dep->slave, &adev);
1802			if (!adev)
1803				continue;
1804
1805			adev->dep_unmet--;
1806			if (!adev->dep_unmet)
1807				acpi_bus_attach(adev);
1808			list_del(&dep->node);
1809			kfree(dep);
1810		}
1811	}
1812	mutex_unlock(&acpi_dep_list_lock);
1813}
1814EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1815
1816/**
1817 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1818 * @handle: Root of the namespace scope to scan.
1819 *
1820 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1821 * found devices.
1822 *
1823 * If no devices were found, -ENODEV is returned, but it does not mean that
1824 * there has been a real error.  There just have been no suitable ACPI objects
1825 * in the table trunk from which the kernel could create a device and add an
1826 * appropriate driver.
1827 *
1828 * Must be called under acpi_scan_lock.
1829 */
1830int acpi_bus_scan(acpi_handle handle)
1831{
1832	void *device = NULL;
1833
1834	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1835		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1836				    acpi_bus_check_add, NULL, NULL, &device);
1837
1838	if (device) {
1839		acpi_bus_attach(device);
1840		return 0;
1841	}
1842	return -ENODEV;
1843}
1844EXPORT_SYMBOL(acpi_bus_scan);
1845
1846/**
1847 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1848 * @adev: Root of the ACPI namespace scope to walk.
1849 *
1850 * Must be called under acpi_scan_lock.
1851 */
1852void acpi_bus_trim(struct acpi_device *adev)
1853{
1854	struct acpi_scan_handler *handler = adev->handler;
1855	struct acpi_device *child;
1856
1857	list_for_each_entry_reverse(child, &adev->children, node)
1858		acpi_bus_trim(child);
 
 
1859
1860	adev->flags.match_driver = false;
1861	if (handler) {
1862		if (handler->detach)
1863			handler->detach(adev);
1864
1865		adev->handler = NULL;
1866	} else {
1867		device_release_driver(&adev->dev);
 
 
 
 
 
 
 
 
 
 
 
 
1868	}
1869	/*
1870	 * Most likely, the device is going away, so put it into D3cold before
1871	 * that.
1872	 */
1873	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1874	adev->flags.initialized = false;
1875	adev->flags.visited = false;
1876}
1877EXPORT_SYMBOL_GPL(acpi_bus_trim);
1878
1879static int acpi_bus_scan_fixed(void)
1880{
1881	int result = 0;
 
 
 
 
 
 
1882
1883	/*
1884	 * Enumerate all fixed-feature devices.
1885	 */
1886	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1887		struct acpi_device *device = NULL;
1888
1889		result = acpi_add_single_object(&device, NULL,
1890						ACPI_BUS_TYPE_POWER_BUTTON,
1891						ACPI_STA_DEFAULT);
1892		if (result)
1893			return result;
1894
1895		device->flags.match_driver = true;
1896		result = device_attach(&device->dev);
1897		if (result < 0)
1898			return result;
1899
1900		device_init_wakeup(&device->dev, true);
1901	}
1902
1903	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1904		struct acpi_device *device = NULL;
1905
1906		result = acpi_add_single_object(&device, NULL,
1907						ACPI_BUS_TYPE_SLEEP_BUTTON,
1908						ACPI_STA_DEFAULT);
1909		if (result)
1910			return result;
1911
1912		device->flags.match_driver = true;
1913		result = device_attach(&device->dev);
1914	}
1915
1916	return result < 0 ? result : 0;
1917}
1918
1919int __init acpi_scan_init(void)
1920{
1921	int result;
 
1922
1923	acpi_pci_root_init();
1924	acpi_pci_link_init();
1925	acpi_processor_init();
1926	acpi_lpss_init();
1927	acpi_apd_init();
1928	acpi_cmos_rtc_init();
1929	acpi_container_init();
1930	acpi_memory_hotplug_init();
1931	acpi_pnp_init();
1932	acpi_int340x_thermal_init();
1933	acpi_amba_init();
1934
1935	acpi_scan_add_handler(&generic_device_handler);
 
 
 
 
 
 
1936
1937	mutex_lock(&acpi_scan_lock);
1938	/*
1939	 * Enumerate devices in the ACPI namespace.
1940	 */
1941	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
1942	if (result)
1943		goto out;
1944
1945	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
1946	if (result)
1947		goto out;
1948
1949	/* Fixed feature devices do not exist on HW-reduced platform */
1950	if (!acpi_gbl_reduced_hardware) {
1951		result = acpi_bus_scan_fixed();
1952		if (result) {
1953			acpi_detach_data(acpi_root->handle,
1954					 acpi_scan_drop_device);
1955			acpi_device_del(acpi_root);
1956			put_device(&acpi_root->dev);
1957			goto out;
1958		}
1959	}
1960
1961	acpi_update_all_gpes();
 
 
 
1962
1963 out:
1964	mutex_unlock(&acpi_scan_lock);
1965	return result;
1966}
1967
1968static struct acpi_probe_entry *ape;
1969static int acpi_probe_count;
1970static DEFINE_SPINLOCK(acpi_probe_lock);
1971
1972static int __init acpi_match_madt(struct acpi_subtable_header *header,
1973				  const unsigned long end)
1974{
1975	if (!ape->subtable_valid || ape->subtable_valid(header, ape))
1976		if (!ape->probe_subtbl(header, end))
1977			acpi_probe_count++;
1978
1979	return 0;
1980}
1981
1982int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
1983{
1984	int count = 0;
1985
1986	if (acpi_disabled)
1987		return 0;
1988
1989	spin_lock(&acpi_probe_lock);
1990	for (ape = ap_head; nr; ape++, nr--) {
1991		if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
1992			acpi_probe_count = 0;
1993			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
1994			count += acpi_probe_count;
1995		} else {
1996			int res;
1997			res = acpi_table_parse(ape->id, ape->probe_table);
1998			if (!res)
1999				count++;
2000		}
2001	}
2002	spin_unlock(&acpi_probe_lock);
2003
2004	return count;
2005}