xref: /openbmc/linux/drivers/acpi/scan.c (revision ee8a99bd)
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 
15 #include <acpi/acpi_drivers.h>
16 
17 #include "internal.h"
18 
19 #define _COMPONENT		ACPI_BUS_COMPONENT
20 ACPI_MODULE_NAME("scan");
21 #define STRUCT_TO_INT(s)	(*((int*)&s))
22 extern 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 /*
31  * If set, devices will be hot-removed even if they cannot be put offline
32  * gracefully (from the kernel's standpoint).
33  */
34 bool acpi_force_hot_remove;
35 
36 static const char *dummy_hid = "device";
37 
38 static LIST_HEAD(acpi_bus_id_list);
39 static DEFINE_MUTEX(acpi_scan_lock);
40 static LIST_HEAD(acpi_scan_handlers_list);
41 DEFINE_MUTEX(acpi_device_lock);
42 LIST_HEAD(acpi_wakeup_device_list);
43 
44 struct acpi_device_bus_id{
45 	char bus_id[15];
46 	unsigned int instance_no;
47 	struct list_head node;
48 };
49 
50 void acpi_scan_lock_acquire(void)
51 {
52 	mutex_lock(&acpi_scan_lock);
53 }
54 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
55 
56 void acpi_scan_lock_release(void)
57 {
58 	mutex_unlock(&acpi_scan_lock);
59 }
60 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
61 
62 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
63 {
64 	if (!handler || !handler->attach)
65 		return -EINVAL;
66 
67 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
68 	return 0;
69 }
70 
71 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
72 				       const char *hotplug_profile_name)
73 {
74 	int error;
75 
76 	error = acpi_scan_add_handler(handler);
77 	if (error)
78 		return error;
79 
80 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
81 	return 0;
82 }
83 
84 /*
85  * Creates hid/cid(s) string needed for modalias and uevent
86  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
87  * char *modalias: "acpi:IBM0001:ACPI0001"
88 */
89 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
90 			   int size)
91 {
92 	int len;
93 	int count;
94 	struct acpi_hardware_id *id;
95 
96 	if (list_empty(&acpi_dev->pnp.ids))
97 		return 0;
98 
99 	len = snprintf(modalias, size, "acpi:");
100 	size -= len;
101 
102 	list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
103 		count = snprintf(&modalias[len], size, "%s:", id->id);
104 		if (count < 0 || count >= size)
105 			return -EINVAL;
106 		len += count;
107 		size -= count;
108 	}
109 
110 	modalias[len] = '\0';
111 	return len;
112 }
113 
114 static ssize_t
115 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
116 	struct acpi_device *acpi_dev = to_acpi_device(dev);
117 	int len;
118 
119 	/* Device has no HID and no CID or string is >1024 */
120 	len = create_modalias(acpi_dev, buf, 1024);
121 	if (len <= 0)
122 		return 0;
123 	buf[len++] = '\n';
124 	return len;
125 }
126 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
127 
128 static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl,
129 					       void *data, void **ret_p)
130 {
131 	struct acpi_device *device = NULL;
132 	struct acpi_device_physical_node *pn;
133 	bool second_pass = (bool)data;
134 	acpi_status status = AE_OK;
135 
136 	if (acpi_bus_get_device(handle, &device))
137 		return AE_OK;
138 
139 	mutex_lock(&device->physical_node_lock);
140 
141 	list_for_each_entry(pn, &device->physical_node_list, node) {
142 		int ret;
143 
144 		if (second_pass) {
145 			/* Skip devices offlined by the first pass. */
146 			if (pn->put_online)
147 				continue;
148 		} else {
149 			pn->put_online = false;
150 		}
151 		ret = device_offline(pn->dev);
152 		if (acpi_force_hot_remove)
153 			continue;
154 
155 		if (ret >= 0) {
156 			pn->put_online = !ret;
157 		} else {
158 			*ret_p = pn->dev;
159 			if (second_pass) {
160 				status = AE_ERROR;
161 				break;
162 			}
163 		}
164 	}
165 
166 	mutex_unlock(&device->physical_node_lock);
167 
168 	return status;
169 }
170 
171 static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl,
172 					      void *data, void **ret_p)
173 {
174 	struct acpi_device *device = NULL;
175 	struct acpi_device_physical_node *pn;
176 
177 	if (acpi_bus_get_device(handle, &device))
178 		return AE_OK;
179 
180 	mutex_lock(&device->physical_node_lock);
181 
182 	list_for_each_entry(pn, &device->physical_node_list, node)
183 		if (pn->put_online) {
184 			device_online(pn->dev);
185 			pn->put_online = false;
186 		}
187 
188 	mutex_unlock(&device->physical_node_lock);
189 
190 	return AE_OK;
191 }
192 
193 static int acpi_scan_hot_remove(struct acpi_device *device)
194 {
195 	acpi_handle handle = device->handle;
196 	acpi_handle not_used;
197 	struct acpi_object_list arg_list;
198 	union acpi_object arg;
199 	struct device *errdev;
200 	acpi_status status;
201 	unsigned long long sta;
202 
203 	/* If there is no handle, the device node has been unregistered. */
204 	if (!handle) {
205 		dev_dbg(&device->dev, "ACPI handle missing\n");
206 		put_device(&device->dev);
207 		return -EINVAL;
208 	}
209 
210 	lock_device_hotplug();
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 	errdev = NULL;
222 	acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
223 			    NULL, acpi_bus_offline_companions,
224 			    (void *)false, (void **)&errdev);
225 	acpi_bus_offline_companions(handle, 0, (void *)false, (void **)&errdev);
226 	if (errdev) {
227 		errdev = NULL;
228 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
229 				    NULL, acpi_bus_offline_companions,
230 				    (void *)true , (void **)&errdev);
231 		if (!errdev || acpi_force_hot_remove)
232 			acpi_bus_offline_companions(handle, 0, (void *)true,
233 						    (void **)&errdev);
234 
235 		if (errdev && !acpi_force_hot_remove) {
236 			dev_warn(errdev, "Offline failed.\n");
237 			acpi_bus_online_companions(handle, 0, NULL, NULL);
238 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
239 					    ACPI_UINT32_MAX,
240 					    acpi_bus_online_companions, NULL,
241 					    NULL, NULL);
242 
243 			unlock_device_hotplug();
244 
245 			put_device(&device->dev);
246 			return -EBUSY;
247 		}
248 	}
249 
250 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
251 		"Hot-removing device %s...\n", dev_name(&device->dev)));
252 
253 	acpi_bus_trim(device);
254 
255 	unlock_device_hotplug();
256 
257 	/* Device node has been unregistered. */
258 	put_device(&device->dev);
259 	device = NULL;
260 
261 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &not_used))) {
262 		arg_list.count = 1;
263 		arg_list.pointer = &arg;
264 		arg.type = ACPI_TYPE_INTEGER;
265 		arg.integer.value = 0;
266 		acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
267 	}
268 
269 	arg_list.count = 1;
270 	arg_list.pointer = &arg;
271 	arg.type = ACPI_TYPE_INTEGER;
272 	arg.integer.value = 1;
273 
274 	/*
275 	 * TBD: _EJD support.
276 	 */
277 	status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
278 	if (ACPI_FAILURE(status)) {
279 		if (status == AE_NOT_FOUND) {
280 			return -ENODEV;
281 		} else {
282 			acpi_handle_warn(handle, "Eject failed (0x%x)\n",
283 								status);
284 			return -EIO;
285 		}
286 	}
287 
288 	/*
289 	 * Verify if eject was indeed successful.  If not, log an error
290 	 * message.  No need to call _OST since _EJ0 call was made OK.
291 	 */
292 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
293 	if (ACPI_FAILURE(status)) {
294 		acpi_handle_warn(handle,
295 			"Status check after eject failed (0x%x)\n", status);
296 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
297 		acpi_handle_warn(handle,
298 			"Eject incomplete - status 0x%llx\n", sta);
299 	}
300 
301 	return 0;
302 }
303 
304 static void acpi_bus_device_eject(void *context)
305 {
306 	acpi_handle handle = context;
307 	struct acpi_device *device = NULL;
308 	struct acpi_scan_handler *handler;
309 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
310 
311 	mutex_lock(&acpi_scan_lock);
312 
313 	acpi_bus_get_device(handle, &device);
314 	if (!device)
315 		goto err_out;
316 
317 	handler = device->handler;
318 	if (!handler || !handler->hotplug.enabled) {
319 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
320 		goto err_out;
321 	}
322 	acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
323 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
324 	if (handler->hotplug.mode == AHM_CONTAINER) {
325 		device->flags.eject_pending = true;
326 		kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
327 	} else {
328 		int error;
329 
330 		get_device(&device->dev);
331 		error = acpi_scan_hot_remove(device);
332 		if (error)
333 			goto err_out;
334 	}
335 
336  out:
337 	mutex_unlock(&acpi_scan_lock);
338 	return;
339 
340  err_out:
341 	acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
342 				  NULL);
343 	goto out;
344 }
345 
346 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
347 {
348 	struct acpi_device *device = NULL;
349 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
350 	int error;
351 
352 	mutex_lock(&acpi_scan_lock);
353 	lock_device_hotplug();
354 
355 	if (ost_source != ACPI_NOTIFY_BUS_CHECK) {
356 		acpi_bus_get_device(handle, &device);
357 		if (device) {
358 			dev_warn(&device->dev, "Attempt to re-insert\n");
359 			goto out;
360 		}
361 	}
362 	acpi_evaluate_hotplug_ost(handle, ost_source,
363 				  ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
364 	error = acpi_bus_scan(handle);
365 	if (error) {
366 		acpi_handle_warn(handle, "Namespace scan failure\n");
367 		goto out;
368 	}
369 	error = acpi_bus_get_device(handle, &device);
370 	if (error) {
371 		acpi_handle_warn(handle, "Missing device node object\n");
372 		goto out;
373 	}
374 	ost_code = ACPI_OST_SC_SUCCESS;
375 	if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
376 		kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
377 
378  out:
379 	unlock_device_hotplug();
380 	acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
381 	mutex_unlock(&acpi_scan_lock);
382 }
383 
384 static void acpi_scan_bus_check(void *context)
385 {
386 	acpi_scan_bus_device_check((acpi_handle)context,
387 				   ACPI_NOTIFY_BUS_CHECK);
388 }
389 
390 static void acpi_scan_device_check(void *context)
391 {
392 	acpi_scan_bus_device_check((acpi_handle)context,
393 				   ACPI_NOTIFY_DEVICE_CHECK);
394 }
395 
396 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
397 {
398 	u32 ost_status;
399 
400 	switch (type) {
401 	case ACPI_NOTIFY_BUS_CHECK:
402 		acpi_handle_debug(handle,
403 			"ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
404 		ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
405 		break;
406 	case ACPI_NOTIFY_DEVICE_CHECK:
407 		acpi_handle_debug(handle,
408 			"ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
409 		ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
410 		break;
411 	case ACPI_NOTIFY_EJECT_REQUEST:
412 		acpi_handle_debug(handle,
413 			"ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
414 		ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
415 		break;
416 	default:
417 		/* non-hotplug event; possibly handled by other handler */
418 		return;
419 	}
420 
421 	acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
422 }
423 
424 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
425 {
426 	acpi_osd_exec_callback callback;
427 	struct acpi_scan_handler *handler = data;
428 	acpi_status status;
429 
430 	if (!handler->hotplug.enabled)
431 		return acpi_hotplug_unsupported(handle, type);
432 
433 	switch (type) {
434 	case ACPI_NOTIFY_BUS_CHECK:
435 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
436 		callback = acpi_scan_bus_check;
437 		break;
438 	case ACPI_NOTIFY_DEVICE_CHECK:
439 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
440 		callback = acpi_scan_device_check;
441 		break;
442 	case ACPI_NOTIFY_EJECT_REQUEST:
443 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
444 		callback = acpi_bus_device_eject;
445 		break;
446 	default:
447 		/* non-hotplug event; possibly handled by other handler */
448 		return;
449 	}
450 	status = acpi_os_hotplug_execute(callback, handle);
451 	if (ACPI_FAILURE(status))
452 		acpi_evaluate_hotplug_ost(handle, type,
453 					  ACPI_OST_SC_NON_SPECIFIC_FAILURE,
454 					  NULL);
455 }
456 
457 /**
458  * acpi_bus_hot_remove_device: hot-remove a device and its children
459  * @context: struct acpi_eject_event pointer (freed in this func)
460  *
461  * Hot-remove a device and its children. This function frees up the
462  * memory space passed by arg context, so that the caller may call
463  * this function asynchronously through acpi_os_hotplug_execute().
464  */
465 void acpi_bus_hot_remove_device(void *context)
466 {
467 	struct acpi_eject_event *ej_event = context;
468 	struct acpi_device *device = ej_event->device;
469 	acpi_handle handle = device->handle;
470 	int error;
471 
472 	mutex_lock(&acpi_scan_lock);
473 
474 	error = acpi_scan_hot_remove(device);
475 	if (error && handle)
476 		acpi_evaluate_hotplug_ost(handle, ej_event->event,
477 					  ACPI_OST_SC_NON_SPECIFIC_FAILURE,
478 					  NULL);
479 
480 	mutex_unlock(&acpi_scan_lock);
481 	kfree(context);
482 }
483 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
484 
485 static ssize_t real_power_state_show(struct device *dev,
486 				     struct device_attribute *attr, char *buf)
487 {
488 	struct acpi_device *adev = to_acpi_device(dev);
489 	int state;
490 	int ret;
491 
492 	ret = acpi_device_get_power(adev, &state);
493 	if (ret)
494 		return ret;
495 
496 	return sprintf(buf, "%s\n", acpi_power_state_string(state));
497 }
498 
499 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
500 
501 static ssize_t power_state_show(struct device *dev,
502 				struct device_attribute *attr, char *buf)
503 {
504 	struct acpi_device *adev = to_acpi_device(dev);
505 
506 	return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
507 }
508 
509 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
510 
511 static ssize_t
512 acpi_eject_store(struct device *d, struct device_attribute *attr,
513 		const char *buf, size_t count)
514 {
515 	struct acpi_device *acpi_device = to_acpi_device(d);
516 	struct acpi_eject_event *ej_event;
517 	acpi_object_type not_used;
518 	acpi_status status;
519 	u32 ost_source;
520 	int ret;
521 
522 	if (!count || buf[0] != '1')
523 		return -EINVAL;
524 
525 	if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
526 	    && !acpi_device->driver)
527 		return -ENODEV;
528 
529 	status = acpi_get_type(acpi_device->handle, &not_used);
530 	if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
531 		return -ENODEV;
532 
533 	mutex_lock(&acpi_scan_lock);
534 
535 	if (acpi_device->flags.eject_pending) {
536 		/* ACPI eject notification event. */
537 		ost_source = ACPI_NOTIFY_EJECT_REQUEST;
538 		acpi_device->flags.eject_pending = 0;
539 	} else {
540 		/* Eject initiated by user space. */
541 		ost_source = ACPI_OST_EC_OSPM_EJECT;
542 	}
543 	ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
544 	if (!ej_event) {
545 		ret = -ENOMEM;
546 		goto err_out;
547 	}
548 	acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
549 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
550 	ej_event->device = acpi_device;
551 	ej_event->event = ost_source;
552 	get_device(&acpi_device->dev);
553 	status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
554 	if (ACPI_FAILURE(status)) {
555 		put_device(&acpi_device->dev);
556 		kfree(ej_event);
557 		ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
558 		goto err_out;
559 	}
560 	ret = count;
561 
562  out:
563 	mutex_unlock(&acpi_scan_lock);
564 	return ret;
565 
566  err_out:
567 	acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
568 				  ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
569 	goto out;
570 }
571 
572 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
573 
574 static ssize_t
575 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
576 	struct acpi_device *acpi_dev = to_acpi_device(dev);
577 
578 	return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
579 }
580 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
581 
582 static ssize_t acpi_device_uid_show(struct device *dev,
583 				    struct device_attribute *attr, char *buf)
584 {
585 	struct acpi_device *acpi_dev = to_acpi_device(dev);
586 
587 	return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
588 }
589 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
590 
591 static ssize_t acpi_device_adr_show(struct device *dev,
592 				    struct device_attribute *attr, char *buf)
593 {
594 	struct acpi_device *acpi_dev = to_acpi_device(dev);
595 
596 	return sprintf(buf, "0x%08x\n",
597 		       (unsigned int)(acpi_dev->pnp.bus_address));
598 }
599 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
600 
601 static ssize_t
602 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
603 	struct acpi_device *acpi_dev = to_acpi_device(dev);
604 	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
605 	int result;
606 
607 	result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
608 	if (result)
609 		goto end;
610 
611 	result = sprintf(buf, "%s\n", (char*)path.pointer);
612 	kfree(path.pointer);
613 end:
614 	return result;
615 }
616 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
617 
618 /* sysfs file that shows description text from the ACPI _STR method */
619 static ssize_t description_show(struct device *dev,
620 				struct device_attribute *attr,
621 				char *buf) {
622 	struct acpi_device *acpi_dev = to_acpi_device(dev);
623 	int result;
624 
625 	if (acpi_dev->pnp.str_obj == NULL)
626 		return 0;
627 
628 	/*
629 	 * The _STR object contains a Unicode identifier for a device.
630 	 * We need to convert to utf-8 so it can be displayed.
631 	 */
632 	result = utf16s_to_utf8s(
633 		(wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
634 		acpi_dev->pnp.str_obj->buffer.length,
635 		UTF16_LITTLE_ENDIAN, buf,
636 		PAGE_SIZE);
637 
638 	buf[result++] = '\n';
639 
640 	return result;
641 }
642 static DEVICE_ATTR(description, 0444, description_show, NULL);
643 
644 static ssize_t
645 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
646 		     char *buf) {
647 	struct acpi_device *acpi_dev = to_acpi_device(dev);
648 
649 	return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
650 }
651 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
652 
653 static int acpi_device_setup_files(struct acpi_device *dev)
654 {
655 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
656 	acpi_status status;
657 	acpi_handle temp;
658 	unsigned long long sun;
659 	int result = 0;
660 
661 	/*
662 	 * Devices gotten from FADT don't have a "path" attribute
663 	 */
664 	if (dev->handle) {
665 		result = device_create_file(&dev->dev, &dev_attr_path);
666 		if (result)
667 			goto end;
668 	}
669 
670 	if (!list_empty(&dev->pnp.ids)) {
671 		result = device_create_file(&dev->dev, &dev_attr_hid);
672 		if (result)
673 			goto end;
674 
675 		result = device_create_file(&dev->dev, &dev_attr_modalias);
676 		if (result)
677 			goto end;
678 	}
679 
680 	/*
681 	 * If device has _STR, 'description' file is created
682 	 */
683 	status = acpi_get_handle(dev->handle, "_STR", &temp);
684 	if (ACPI_SUCCESS(status)) {
685 		status = acpi_evaluate_object(dev->handle, "_STR",
686 					NULL, &buffer);
687 		if (ACPI_FAILURE(status))
688 			buffer.pointer = NULL;
689 		dev->pnp.str_obj = buffer.pointer;
690 		result = device_create_file(&dev->dev, &dev_attr_description);
691 		if (result)
692 			goto end;
693 	}
694 
695 	if (dev->pnp.type.bus_address)
696 		result = device_create_file(&dev->dev, &dev_attr_adr);
697 	if (dev->pnp.unique_id)
698 		result = device_create_file(&dev->dev, &dev_attr_uid);
699 
700 	status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
701 	if (ACPI_SUCCESS(status)) {
702 		dev->pnp.sun = (unsigned long)sun;
703 		result = device_create_file(&dev->dev, &dev_attr_sun);
704 		if (result)
705 			goto end;
706 	} else {
707 		dev->pnp.sun = (unsigned long)-1;
708 	}
709 
710         /*
711          * If device has _EJ0, 'eject' file is created that is used to trigger
712          * hot-removal function from userland.
713          */
714 	status = acpi_get_handle(dev->handle, "_EJ0", &temp);
715 	if (ACPI_SUCCESS(status)) {
716 		result = device_create_file(&dev->dev, &dev_attr_eject);
717 		if (result)
718 			return result;
719 	}
720 
721 	if (dev->flags.power_manageable) {
722 		result = device_create_file(&dev->dev, &dev_attr_power_state);
723 		if (result)
724 			return result;
725 
726 		if (dev->power.flags.power_resources)
727 			result = device_create_file(&dev->dev,
728 						    &dev_attr_real_power_state);
729 	}
730 
731 end:
732 	return result;
733 }
734 
735 static void acpi_device_remove_files(struct acpi_device *dev)
736 {
737 	acpi_status status;
738 	acpi_handle temp;
739 
740 	if (dev->flags.power_manageable) {
741 		device_remove_file(&dev->dev, &dev_attr_power_state);
742 		if (dev->power.flags.power_resources)
743 			device_remove_file(&dev->dev,
744 					   &dev_attr_real_power_state);
745 	}
746 
747 	/*
748 	 * If device has _STR, remove 'description' file
749 	 */
750 	status = acpi_get_handle(dev->handle, "_STR", &temp);
751 	if (ACPI_SUCCESS(status)) {
752 		kfree(dev->pnp.str_obj);
753 		device_remove_file(&dev->dev, &dev_attr_description);
754 	}
755 	/*
756 	 * If device has _EJ0, remove 'eject' file.
757 	 */
758 	status = acpi_get_handle(dev->handle, "_EJ0", &temp);
759 	if (ACPI_SUCCESS(status))
760 		device_remove_file(&dev->dev, &dev_attr_eject);
761 
762 	status = acpi_get_handle(dev->handle, "_SUN", &temp);
763 	if (ACPI_SUCCESS(status))
764 		device_remove_file(&dev->dev, &dev_attr_sun);
765 
766 	if (dev->pnp.unique_id)
767 		device_remove_file(&dev->dev, &dev_attr_uid);
768 	if (dev->pnp.type.bus_address)
769 		device_remove_file(&dev->dev, &dev_attr_adr);
770 	device_remove_file(&dev->dev, &dev_attr_modalias);
771 	device_remove_file(&dev->dev, &dev_attr_hid);
772 	if (dev->handle)
773 		device_remove_file(&dev->dev, &dev_attr_path);
774 }
775 /* --------------------------------------------------------------------------
776 			ACPI Bus operations
777    -------------------------------------------------------------------------- */
778 
779 static const struct acpi_device_id *__acpi_match_device(
780 	struct acpi_device *device, const struct acpi_device_id *ids)
781 {
782 	const struct acpi_device_id *id;
783 	struct acpi_hardware_id *hwid;
784 
785 	/*
786 	 * If the device is not present, it is unnecessary to load device
787 	 * driver for it.
788 	 */
789 	if (!device->status.present)
790 		return NULL;
791 
792 	for (id = ids; id->id[0]; id++)
793 		list_for_each_entry(hwid, &device->pnp.ids, list)
794 			if (!strcmp((char *) id->id, hwid->id))
795 				return id;
796 
797 	return NULL;
798 }
799 
800 /**
801  * acpi_match_device - Match a struct device against a given list of ACPI IDs
802  * @ids: Array of struct acpi_device_id object to match against.
803  * @dev: The device structure to match.
804  *
805  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
806  * object for that handle and use that object to match against a given list of
807  * device IDs.
808  *
809  * Return a pointer to the first matching ID on success or %NULL on failure.
810  */
811 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
812 					       const struct device *dev)
813 {
814 	struct acpi_device *adev;
815 	acpi_handle handle = ACPI_HANDLE(dev);
816 
817 	if (!ids || !handle || acpi_bus_get_device(handle, &adev))
818 		return NULL;
819 
820 	return __acpi_match_device(adev, ids);
821 }
822 EXPORT_SYMBOL_GPL(acpi_match_device);
823 
824 int acpi_match_device_ids(struct acpi_device *device,
825 			  const struct acpi_device_id *ids)
826 {
827 	return __acpi_match_device(device, ids) ? 0 : -ENOENT;
828 }
829 EXPORT_SYMBOL(acpi_match_device_ids);
830 
831 static void acpi_free_power_resources_lists(struct acpi_device *device)
832 {
833 	int i;
834 
835 	if (device->wakeup.flags.valid)
836 		acpi_power_resources_list_free(&device->wakeup.resources);
837 
838 	if (!device->flags.power_manageable)
839 		return;
840 
841 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
842 		struct acpi_device_power_state *ps = &device->power.states[i];
843 		acpi_power_resources_list_free(&ps->resources);
844 	}
845 }
846 
847 static void acpi_device_release(struct device *dev)
848 {
849 	struct acpi_device *acpi_dev = to_acpi_device(dev);
850 
851 	acpi_free_pnp_ids(&acpi_dev->pnp);
852 	acpi_free_power_resources_lists(acpi_dev);
853 	kfree(acpi_dev);
854 }
855 
856 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
857 {
858 	struct acpi_device *acpi_dev = to_acpi_device(dev);
859 	struct acpi_driver *acpi_drv = to_acpi_driver(drv);
860 
861 	return acpi_dev->flags.match_driver
862 		&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
863 }
864 
865 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
866 {
867 	struct acpi_device *acpi_dev = to_acpi_device(dev);
868 	int len;
869 
870 	if (list_empty(&acpi_dev->pnp.ids))
871 		return 0;
872 
873 	if (add_uevent_var(env, "MODALIAS="))
874 		return -ENOMEM;
875 	len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
876 			      sizeof(env->buf) - env->buflen);
877 	if (len >= (sizeof(env->buf) - env->buflen))
878 		return -ENOMEM;
879 	env->buflen += len;
880 	return 0;
881 }
882 
883 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
884 {
885 	struct acpi_device *device = data;
886 
887 	device->driver->ops.notify(device, event);
888 }
889 
890 static acpi_status acpi_device_notify_fixed(void *data)
891 {
892 	struct acpi_device *device = data;
893 
894 	/* Fixed hardware devices have no handles */
895 	acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
896 	return AE_OK;
897 }
898 
899 static int acpi_device_install_notify_handler(struct acpi_device *device)
900 {
901 	acpi_status status;
902 
903 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
904 		status =
905 		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
906 						     acpi_device_notify_fixed,
907 						     device);
908 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
909 		status =
910 		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
911 						     acpi_device_notify_fixed,
912 						     device);
913 	else
914 		status = acpi_install_notify_handler(device->handle,
915 						     ACPI_DEVICE_NOTIFY,
916 						     acpi_device_notify,
917 						     device);
918 
919 	if (ACPI_FAILURE(status))
920 		return -EINVAL;
921 	return 0;
922 }
923 
924 static void acpi_device_remove_notify_handler(struct acpi_device *device)
925 {
926 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
927 		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
928 						acpi_device_notify_fixed);
929 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
930 		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
931 						acpi_device_notify_fixed);
932 	else
933 		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
934 					   acpi_device_notify);
935 }
936 
937 static int acpi_device_probe(struct device *dev)
938 {
939 	struct acpi_device *acpi_dev = to_acpi_device(dev);
940 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
941 	int ret;
942 
943 	if (acpi_dev->handler)
944 		return -EINVAL;
945 
946 	if (!acpi_drv->ops.add)
947 		return -ENOSYS;
948 
949 	ret = acpi_drv->ops.add(acpi_dev);
950 	if (ret)
951 		return ret;
952 
953 	acpi_dev->driver = acpi_drv;
954 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
955 			  "Driver [%s] successfully bound to device [%s]\n",
956 			  acpi_drv->name, acpi_dev->pnp.bus_id));
957 
958 	if (acpi_drv->ops.notify) {
959 		ret = acpi_device_install_notify_handler(acpi_dev);
960 		if (ret) {
961 			if (acpi_drv->ops.remove)
962 				acpi_drv->ops.remove(acpi_dev);
963 
964 			acpi_dev->driver = NULL;
965 			acpi_dev->driver_data = NULL;
966 			return ret;
967 		}
968 	}
969 
970 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
971 			  acpi_drv->name, acpi_dev->pnp.bus_id));
972 	get_device(dev);
973 	return 0;
974 }
975 
976 static int acpi_device_remove(struct device * dev)
977 {
978 	struct acpi_device *acpi_dev = to_acpi_device(dev);
979 	struct acpi_driver *acpi_drv = acpi_dev->driver;
980 
981 	if (acpi_drv) {
982 		if (acpi_drv->ops.notify)
983 			acpi_device_remove_notify_handler(acpi_dev);
984 		if (acpi_drv->ops.remove)
985 			acpi_drv->ops.remove(acpi_dev);
986 	}
987 	acpi_dev->driver = NULL;
988 	acpi_dev->driver_data = NULL;
989 
990 	put_device(dev);
991 	return 0;
992 }
993 
994 struct bus_type acpi_bus_type = {
995 	.name		= "acpi",
996 	.match		= acpi_bus_match,
997 	.probe		= acpi_device_probe,
998 	.remove		= acpi_device_remove,
999 	.uevent		= acpi_device_uevent,
1000 };
1001 
1002 int acpi_device_add(struct acpi_device *device,
1003 		    void (*release)(struct device *))
1004 {
1005 	int result;
1006 	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1007 	int found = 0;
1008 
1009 	if (device->handle) {
1010 		acpi_status status;
1011 
1012 		status = acpi_attach_data(device->handle, acpi_bus_data_handler,
1013 					  device);
1014 		if (ACPI_FAILURE(status)) {
1015 			acpi_handle_err(device->handle,
1016 					"Unable to attach device data\n");
1017 			return -ENODEV;
1018 		}
1019 	}
1020 
1021 	/*
1022 	 * Linkage
1023 	 * -------
1024 	 * Link this device to its parent and siblings.
1025 	 */
1026 	INIT_LIST_HEAD(&device->children);
1027 	INIT_LIST_HEAD(&device->node);
1028 	INIT_LIST_HEAD(&device->wakeup_list);
1029 	INIT_LIST_HEAD(&device->physical_node_list);
1030 	mutex_init(&device->physical_node_lock);
1031 	INIT_LIST_HEAD(&device->power_dependent);
1032 
1033 	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1034 	if (!new_bus_id) {
1035 		pr_err(PREFIX "Memory allocation error\n");
1036 		result = -ENOMEM;
1037 		goto err_detach;
1038 	}
1039 
1040 	mutex_lock(&acpi_device_lock);
1041 	/*
1042 	 * Find suitable bus_id and instance number in acpi_bus_id_list
1043 	 * If failed, create one and link it into acpi_bus_id_list
1044 	 */
1045 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1046 		if (!strcmp(acpi_device_bus_id->bus_id,
1047 			    acpi_device_hid(device))) {
1048 			acpi_device_bus_id->instance_no++;
1049 			found = 1;
1050 			kfree(new_bus_id);
1051 			break;
1052 		}
1053 	}
1054 	if (!found) {
1055 		acpi_device_bus_id = new_bus_id;
1056 		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1057 		acpi_device_bus_id->instance_no = 0;
1058 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1059 	}
1060 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1061 
1062 	if (device->parent)
1063 		list_add_tail(&device->node, &device->parent->children);
1064 
1065 	if (device->wakeup.flags.valid)
1066 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1067 	mutex_unlock(&acpi_device_lock);
1068 
1069 	if (device->parent)
1070 		device->dev.parent = &device->parent->dev;
1071 	device->dev.bus = &acpi_bus_type;
1072 	device->dev.release = release;
1073 	result = device_add(&device->dev);
1074 	if (result) {
1075 		dev_err(&device->dev, "Error registering device\n");
1076 		goto err;
1077 	}
1078 
1079 	result = acpi_device_setup_files(device);
1080 	if (result)
1081 		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1082 		       dev_name(&device->dev));
1083 
1084 	return 0;
1085 
1086  err:
1087 	mutex_lock(&acpi_device_lock);
1088 	if (device->parent)
1089 		list_del(&device->node);
1090 	list_del(&device->wakeup_list);
1091 	mutex_unlock(&acpi_device_lock);
1092 
1093  err_detach:
1094 	acpi_detach_data(device->handle, acpi_bus_data_handler);
1095 	return result;
1096 }
1097 
1098 static void acpi_device_unregister(struct acpi_device *device)
1099 {
1100 	mutex_lock(&acpi_device_lock);
1101 	if (device->parent)
1102 		list_del(&device->node);
1103 
1104 	list_del(&device->wakeup_list);
1105 	mutex_unlock(&acpi_device_lock);
1106 
1107 	acpi_detach_data(device->handle, acpi_bus_data_handler);
1108 
1109 	acpi_power_add_remove_device(device, false);
1110 	acpi_device_remove_files(device);
1111 	if (device->remove)
1112 		device->remove(device);
1113 
1114 	device_del(&device->dev);
1115 	/*
1116 	 * Transition the device to D3cold to drop the reference counts of all
1117 	 * power resources the device depends on and turn off the ones that have
1118 	 * no more references.
1119 	 */
1120 	acpi_device_set_power(device, ACPI_STATE_D3_COLD);
1121 	device->handle = NULL;
1122 	put_device(&device->dev);
1123 }
1124 
1125 /* --------------------------------------------------------------------------
1126                                  Driver Management
1127    -------------------------------------------------------------------------- */
1128 /**
1129  * acpi_bus_register_driver - register a driver with the ACPI bus
1130  * @driver: driver being registered
1131  *
1132  * Registers a driver with the ACPI bus.  Searches the namespace for all
1133  * devices that match the driver's criteria and binds.  Returns zero for
1134  * success or a negative error status for failure.
1135  */
1136 int acpi_bus_register_driver(struct acpi_driver *driver)
1137 {
1138 	int ret;
1139 
1140 	if (acpi_disabled)
1141 		return -ENODEV;
1142 	driver->drv.name = driver->name;
1143 	driver->drv.bus = &acpi_bus_type;
1144 	driver->drv.owner = driver->owner;
1145 
1146 	ret = driver_register(&driver->drv);
1147 	return ret;
1148 }
1149 
1150 EXPORT_SYMBOL(acpi_bus_register_driver);
1151 
1152 /**
1153  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1154  * @driver: driver to unregister
1155  *
1156  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1157  * devices that match the driver's criteria and unbinds.
1158  */
1159 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1160 {
1161 	driver_unregister(&driver->drv);
1162 }
1163 
1164 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1165 
1166 /* --------------------------------------------------------------------------
1167                                  Device Enumeration
1168    -------------------------------------------------------------------------- */
1169 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1170 {
1171 	struct acpi_device *device = NULL;
1172 	acpi_status status;
1173 
1174 	/*
1175 	 * Fixed hardware devices do not appear in the namespace and do not
1176 	 * have handles, but we fabricate acpi_devices for them, so we have
1177 	 * to deal with them specially.
1178 	 */
1179 	if (!handle)
1180 		return acpi_root;
1181 
1182 	do {
1183 		status = acpi_get_parent(handle, &handle);
1184 		if (ACPI_FAILURE(status))
1185 			return status == AE_NULL_ENTRY ? NULL : acpi_root;
1186 	} while (acpi_bus_get_device(handle, &device));
1187 	return device;
1188 }
1189 
1190 acpi_status
1191 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1192 {
1193 	acpi_status status;
1194 	acpi_handle tmp;
1195 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1196 	union acpi_object *obj;
1197 
1198 	status = acpi_get_handle(handle, "_EJD", &tmp);
1199 	if (ACPI_FAILURE(status))
1200 		return status;
1201 
1202 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1203 	if (ACPI_SUCCESS(status)) {
1204 		obj = buffer.pointer;
1205 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1206 					 ejd);
1207 		kfree(buffer.pointer);
1208 	}
1209 	return status;
1210 }
1211 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1212 
1213 void acpi_bus_data_handler(acpi_handle handle, void *context)
1214 {
1215 
1216 	/* TBD */
1217 
1218 	return;
1219 }
1220 
1221 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1222 					struct acpi_device_wakeup *wakeup)
1223 {
1224 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1225 	union acpi_object *package = NULL;
1226 	union acpi_object *element = NULL;
1227 	acpi_status status;
1228 	int err = -ENODATA;
1229 
1230 	if (!wakeup)
1231 		return -EINVAL;
1232 
1233 	INIT_LIST_HEAD(&wakeup->resources);
1234 
1235 	/* _PRW */
1236 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1237 	if (ACPI_FAILURE(status)) {
1238 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1239 		return err;
1240 	}
1241 
1242 	package = (union acpi_object *)buffer.pointer;
1243 
1244 	if (!package || package->package.count < 2)
1245 		goto out;
1246 
1247 	element = &(package->package.elements[0]);
1248 	if (!element)
1249 		goto out;
1250 
1251 	if (element->type == ACPI_TYPE_PACKAGE) {
1252 		if ((element->package.count < 2) ||
1253 		    (element->package.elements[0].type !=
1254 		     ACPI_TYPE_LOCAL_REFERENCE)
1255 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1256 			goto out;
1257 
1258 		wakeup->gpe_device =
1259 		    element->package.elements[0].reference.handle;
1260 		wakeup->gpe_number =
1261 		    (u32) element->package.elements[1].integer.value;
1262 	} else if (element->type == ACPI_TYPE_INTEGER) {
1263 		wakeup->gpe_device = NULL;
1264 		wakeup->gpe_number = element->integer.value;
1265 	} else {
1266 		goto out;
1267 	}
1268 
1269 	element = &(package->package.elements[1]);
1270 	if (element->type != ACPI_TYPE_INTEGER)
1271 		goto out;
1272 
1273 	wakeup->sleep_state = element->integer.value;
1274 
1275 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1276 	if (err)
1277 		goto out;
1278 
1279 	if (!list_empty(&wakeup->resources)) {
1280 		int sleep_state;
1281 
1282 		err = acpi_power_wakeup_list_init(&wakeup->resources,
1283 						  &sleep_state);
1284 		if (err) {
1285 			acpi_handle_warn(handle, "Retrieving current states "
1286 					 "of wakeup power resources failed\n");
1287 			acpi_power_resources_list_free(&wakeup->resources);
1288 			goto out;
1289 		}
1290 		if (sleep_state < wakeup->sleep_state) {
1291 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
1292 					 "(S%d) by S%d from power resources\n",
1293 					 (int)wakeup->sleep_state, sleep_state);
1294 			wakeup->sleep_state = sleep_state;
1295 		}
1296 	}
1297 	acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1298 
1299  out:
1300 	kfree(buffer.pointer);
1301 	return err;
1302 }
1303 
1304 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1305 {
1306 	struct acpi_device_id button_device_ids[] = {
1307 		{"PNP0C0C", 0},
1308 		{"PNP0C0D", 0},
1309 		{"PNP0C0E", 0},
1310 		{"", 0},
1311 	};
1312 	acpi_status status;
1313 	acpi_event_status event_status;
1314 
1315 	device->wakeup.flags.notifier_present = 0;
1316 
1317 	/* Power button, Lid switch always enable wakeup */
1318 	if (!acpi_match_device_ids(device, button_device_ids)) {
1319 		device->wakeup.flags.run_wake = 1;
1320 		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1321 			/* Do not use Lid/sleep button for S5 wakeup */
1322 			if (device->wakeup.sleep_state == ACPI_STATE_S5)
1323 				device->wakeup.sleep_state = ACPI_STATE_S4;
1324 		}
1325 		device_set_wakeup_capable(&device->dev, true);
1326 		return;
1327 	}
1328 
1329 	status = acpi_get_gpe_status(device->wakeup.gpe_device,
1330 					device->wakeup.gpe_number,
1331 						&event_status);
1332 	if (status == AE_OK)
1333 		device->wakeup.flags.run_wake =
1334 				!!(event_status & ACPI_EVENT_FLAG_HANDLE);
1335 }
1336 
1337 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1338 {
1339 	acpi_handle temp;
1340 	acpi_status status = 0;
1341 	int err;
1342 
1343 	/* Presence of _PRW indicates wake capable */
1344 	status = acpi_get_handle(device->handle, "_PRW", &temp);
1345 	if (ACPI_FAILURE(status))
1346 		return;
1347 
1348 	err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1349 							   &device->wakeup);
1350 	if (err) {
1351 		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1352 		return;
1353 	}
1354 
1355 	device->wakeup.flags.valid = 1;
1356 	device->wakeup.prepare_count = 0;
1357 	acpi_bus_set_run_wake_flags(device);
1358 	/* Call _PSW/_DSW object to disable its ability to wake the sleeping
1359 	 * system for the ACPI device with the _PRW object.
1360 	 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1361 	 * So it is necessary to call _DSW object first. Only when it is not
1362 	 * present will the _PSW object used.
1363 	 */
1364 	err = acpi_device_sleep_wake(device, 0, 0, 0);
1365 	if (err)
1366 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1367 				"error in _DSW or _PSW evaluation\n"));
1368 }
1369 
1370 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1371 {
1372 	struct acpi_device_power_state *ps = &device->power.states[state];
1373 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1374 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1375 	acpi_handle handle;
1376 	acpi_status status;
1377 
1378 	INIT_LIST_HEAD(&ps->resources);
1379 
1380 	/* Evaluate "_PRx" to get referenced power resources */
1381 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1382 	if (ACPI_SUCCESS(status)) {
1383 		union acpi_object *package = buffer.pointer;
1384 
1385 		if (buffer.length && package
1386 		    && package->type == ACPI_TYPE_PACKAGE
1387 		    && package->package.count) {
1388 			int err = acpi_extract_power_resources(package, 0,
1389 							       &ps->resources);
1390 			if (!err)
1391 				device->power.flags.power_resources = 1;
1392 		}
1393 		ACPI_FREE(buffer.pointer);
1394 	}
1395 
1396 	/* Evaluate "_PSx" to see if we can do explicit sets */
1397 	pathname[2] = 'S';
1398 	status = acpi_get_handle(device->handle, pathname, &handle);
1399 	if (ACPI_SUCCESS(status))
1400 		ps->flags.explicit_set = 1;
1401 
1402 	/*
1403 	 * State is valid if there are means to put the device into it.
1404 	 * D3hot is only valid if _PR3 present.
1405 	 */
1406 	if (!list_empty(&ps->resources)
1407 	    || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1408 		ps->flags.valid = 1;
1409 		ps->flags.os_accessible = 1;
1410 	}
1411 
1412 	ps->power = -1;		/* Unknown - driver assigned */
1413 	ps->latency = -1;	/* Unknown - driver assigned */
1414 }
1415 
1416 static void acpi_bus_get_power_flags(struct acpi_device *device)
1417 {
1418 	acpi_status status;
1419 	acpi_handle handle;
1420 	u32 i;
1421 
1422 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
1423 	status = acpi_get_handle(device->handle, "_PS0", &handle);
1424 	if (ACPI_FAILURE(status)) {
1425 		status = acpi_get_handle(device->handle, "_PR0", &handle);
1426 		if (ACPI_FAILURE(status))
1427 			return;
1428 	}
1429 
1430 	device->flags.power_manageable = 1;
1431 
1432 	/*
1433 	 * Power Management Flags
1434 	 */
1435 	status = acpi_get_handle(device->handle, "_PSC", &handle);
1436 	if (ACPI_SUCCESS(status))
1437 		device->power.flags.explicit_get = 1;
1438 	status = acpi_get_handle(device->handle, "_IRC", &handle);
1439 	if (ACPI_SUCCESS(status))
1440 		device->power.flags.inrush_current = 1;
1441 
1442 	/*
1443 	 * Enumerate supported power management states
1444 	 */
1445 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1446 		acpi_bus_init_power_state(device, i);
1447 
1448 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1449 
1450 	/* Set defaults for D0 and D3 states (always valid) */
1451 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1452 	device->power.states[ACPI_STATE_D0].power = 100;
1453 	device->power.states[ACPI_STATE_D3].flags.valid = 1;
1454 	device->power.states[ACPI_STATE_D3].power = 0;
1455 
1456 	/* Set D3cold's explicit_set flag if _PS3 exists. */
1457 	if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1458 		device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1459 
1460 	/* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1461 	if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1462 			device->power.flags.power_resources)
1463 		device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1464 
1465 	if (acpi_bus_init_power(device)) {
1466 		acpi_free_power_resources_lists(device);
1467 		device->flags.power_manageable = 0;
1468 	}
1469 }
1470 
1471 static void acpi_bus_get_flags(struct acpi_device *device)
1472 {
1473 	acpi_status status = AE_OK;
1474 	acpi_handle temp = NULL;
1475 
1476 	/* Presence of _STA indicates 'dynamic_status' */
1477 	status = acpi_get_handle(device->handle, "_STA", &temp);
1478 	if (ACPI_SUCCESS(status))
1479 		device->flags.dynamic_status = 1;
1480 
1481 	/* Presence of _RMV indicates 'removable' */
1482 	status = acpi_get_handle(device->handle, "_RMV", &temp);
1483 	if (ACPI_SUCCESS(status))
1484 		device->flags.removable = 1;
1485 
1486 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1487 	status = acpi_get_handle(device->handle, "_EJD", &temp);
1488 	if (ACPI_SUCCESS(status))
1489 		device->flags.ejectable = 1;
1490 	else {
1491 		status = acpi_get_handle(device->handle, "_EJ0", &temp);
1492 		if (ACPI_SUCCESS(status))
1493 			device->flags.ejectable = 1;
1494 	}
1495 }
1496 
1497 static void acpi_device_get_busid(struct acpi_device *device)
1498 {
1499 	char bus_id[5] = { '?', 0 };
1500 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1501 	int i = 0;
1502 
1503 	/*
1504 	 * Bus ID
1505 	 * ------
1506 	 * The device's Bus ID is simply the object name.
1507 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1508 	 */
1509 	if (ACPI_IS_ROOT_DEVICE(device)) {
1510 		strcpy(device->pnp.bus_id, "ACPI");
1511 		return;
1512 	}
1513 
1514 	switch (device->device_type) {
1515 	case ACPI_BUS_TYPE_POWER_BUTTON:
1516 		strcpy(device->pnp.bus_id, "PWRF");
1517 		break;
1518 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1519 		strcpy(device->pnp.bus_id, "SLPF");
1520 		break;
1521 	default:
1522 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1523 		/* Clean up trailing underscores (if any) */
1524 		for (i = 3; i > 1; i--) {
1525 			if (bus_id[i] == '_')
1526 				bus_id[i] = '\0';
1527 			else
1528 				break;
1529 		}
1530 		strcpy(device->pnp.bus_id, bus_id);
1531 		break;
1532 	}
1533 }
1534 
1535 /*
1536  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1537  *
1538  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1539  * then we can safely call it an ejectable drive bay
1540  */
1541 static int acpi_bay_match(acpi_handle handle)
1542 {
1543 	acpi_status status;
1544 	acpi_handle tmp;
1545 	acpi_handle phandle;
1546 
1547 	status = acpi_get_handle(handle, "_EJ0", &tmp);
1548 	if (ACPI_FAILURE(status))
1549 		return -ENODEV;
1550 
1551 	if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1552 		(ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1553 		(ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1554 		(ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1555 		return 0;
1556 
1557 	if (acpi_get_parent(handle, &phandle))
1558 		return -ENODEV;
1559 
1560         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1561                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1562                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1563                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1564                 return 0;
1565 
1566 	return -ENODEV;
1567 }
1568 
1569 /*
1570  * acpi_dock_match - see if an acpi object has a _DCK method
1571  */
1572 static int acpi_dock_match(acpi_handle handle)
1573 {
1574 	acpi_handle tmp;
1575 	return acpi_get_handle(handle, "_DCK", &tmp);
1576 }
1577 
1578 const char *acpi_device_hid(struct acpi_device *device)
1579 {
1580 	struct acpi_hardware_id *hid;
1581 
1582 	if (list_empty(&device->pnp.ids))
1583 		return dummy_hid;
1584 
1585 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1586 	return hid->id;
1587 }
1588 EXPORT_SYMBOL(acpi_device_hid);
1589 
1590 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1591 {
1592 	struct acpi_hardware_id *id;
1593 
1594 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1595 	if (!id)
1596 		return;
1597 
1598 	id->id = kstrdup(dev_id, GFP_KERNEL);
1599 	if (!id->id) {
1600 		kfree(id);
1601 		return;
1602 	}
1603 
1604 	list_add_tail(&id->list, &pnp->ids);
1605 	pnp->type.hardware_id = 1;
1606 }
1607 
1608 /*
1609  * Old IBM workstations have a DSDT bug wherein the SMBus object
1610  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1611  * prefix.  Work around this.
1612  */
1613 static int acpi_ibm_smbus_match(acpi_handle handle)
1614 {
1615 	acpi_handle h_dummy;
1616 	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1617 	int result;
1618 
1619 	if (!dmi_name_in_vendors("IBM"))
1620 		return -ENODEV;
1621 
1622 	/* Look for SMBS object */
1623 	result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1624 	if (result)
1625 		return result;
1626 
1627 	if (strcmp("SMBS", path.pointer)) {
1628 		result = -ENODEV;
1629 		goto out;
1630 	}
1631 
1632 	/* Does it have the necessary (but misnamed) methods? */
1633 	result = -ENODEV;
1634 	if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1635 	    ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1636 	    ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1637 		result = 0;
1638 out:
1639 	kfree(path.pointer);
1640 	return result;
1641 }
1642 
1643 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1644 				int device_type)
1645 {
1646 	acpi_status status;
1647 	struct acpi_device_info *info;
1648 	struct acpi_pnp_device_id_list *cid_list;
1649 	int i;
1650 
1651 	switch (device_type) {
1652 	case ACPI_BUS_TYPE_DEVICE:
1653 		if (handle == ACPI_ROOT_OBJECT) {
1654 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1655 			break;
1656 		}
1657 
1658 		status = acpi_get_object_info(handle, &info);
1659 		if (ACPI_FAILURE(status)) {
1660 			pr_err(PREFIX "%s: Error reading device info\n",
1661 					__func__);
1662 			return;
1663 		}
1664 
1665 		if (info->valid & ACPI_VALID_HID)
1666 			acpi_add_id(pnp, info->hardware_id.string);
1667 		if (info->valid & ACPI_VALID_CID) {
1668 			cid_list = &info->compatible_id_list;
1669 			for (i = 0; i < cid_list->count; i++)
1670 				acpi_add_id(pnp, cid_list->ids[i].string);
1671 		}
1672 		if (info->valid & ACPI_VALID_ADR) {
1673 			pnp->bus_address = info->address;
1674 			pnp->type.bus_address = 1;
1675 		}
1676 		if (info->valid & ACPI_VALID_UID)
1677 			pnp->unique_id = kstrdup(info->unique_id.string,
1678 							GFP_KERNEL);
1679 
1680 		kfree(info);
1681 
1682 		/*
1683 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1684 		 * synthetic HIDs to make sure drivers can find them.
1685 		 */
1686 		if (acpi_is_video_device(handle))
1687 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1688 		else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1689 			acpi_add_id(pnp, ACPI_BAY_HID);
1690 		else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1691 			acpi_add_id(pnp, ACPI_DOCK_HID);
1692 		else if (!acpi_ibm_smbus_match(handle))
1693 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1694 		else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1695 			acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1696 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1697 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1698 		}
1699 
1700 		break;
1701 	case ACPI_BUS_TYPE_POWER:
1702 		acpi_add_id(pnp, ACPI_POWER_HID);
1703 		break;
1704 	case ACPI_BUS_TYPE_PROCESSOR:
1705 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1706 		break;
1707 	case ACPI_BUS_TYPE_THERMAL:
1708 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1709 		break;
1710 	case ACPI_BUS_TYPE_POWER_BUTTON:
1711 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1712 		break;
1713 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1714 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1715 		break;
1716 	}
1717 }
1718 
1719 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1720 {
1721 	struct acpi_hardware_id *id, *tmp;
1722 
1723 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1724 		kfree(id->id);
1725 		kfree(id);
1726 	}
1727 	kfree(pnp->unique_id);
1728 }
1729 
1730 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1731 			     int type, unsigned long long sta)
1732 {
1733 	INIT_LIST_HEAD(&device->pnp.ids);
1734 	device->device_type = type;
1735 	device->handle = handle;
1736 	device->parent = acpi_bus_get_parent(handle);
1737 	STRUCT_TO_INT(device->status) = sta;
1738 	acpi_device_get_busid(device);
1739 	acpi_set_pnp_ids(handle, &device->pnp, type);
1740 	acpi_bus_get_flags(device);
1741 	device->flags.match_driver = false;
1742 	device_initialize(&device->dev);
1743 	dev_set_uevent_suppress(&device->dev, true);
1744 }
1745 
1746 void acpi_device_add_finalize(struct acpi_device *device)
1747 {
1748 	device->flags.match_driver = true;
1749 	dev_set_uevent_suppress(&device->dev, false);
1750 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1751 }
1752 
1753 static int acpi_add_single_object(struct acpi_device **child,
1754 				  acpi_handle handle, int type,
1755 				  unsigned long long sta)
1756 {
1757 	int result;
1758 	struct acpi_device *device;
1759 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1760 
1761 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1762 	if (!device) {
1763 		printk(KERN_ERR PREFIX "Memory allocation error\n");
1764 		return -ENOMEM;
1765 	}
1766 
1767 	acpi_init_device_object(device, handle, type, sta);
1768 	acpi_bus_get_power_flags(device);
1769 	acpi_bus_get_wakeup_device_flags(device);
1770 
1771 	result = acpi_device_add(device, acpi_device_release);
1772 	if (result) {
1773 		acpi_device_release(&device->dev);
1774 		return result;
1775 	}
1776 
1777 	acpi_power_add_remove_device(device, true);
1778 	acpi_device_add_finalize(device);
1779 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1780 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1781 		dev_name(&device->dev), (char *) buffer.pointer,
1782 		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1783 	kfree(buffer.pointer);
1784 	*child = device;
1785 	return 0;
1786 }
1787 
1788 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1789 				    unsigned long long *sta)
1790 {
1791 	acpi_status status;
1792 	acpi_object_type acpi_type;
1793 
1794 	status = acpi_get_type(handle, &acpi_type);
1795 	if (ACPI_FAILURE(status))
1796 		return -ENODEV;
1797 
1798 	switch (acpi_type) {
1799 	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1800 	case ACPI_TYPE_DEVICE:
1801 		*type = ACPI_BUS_TYPE_DEVICE;
1802 		status = acpi_bus_get_status_handle(handle, sta);
1803 		if (ACPI_FAILURE(status))
1804 			return -ENODEV;
1805 		break;
1806 	case ACPI_TYPE_PROCESSOR:
1807 		*type = ACPI_BUS_TYPE_PROCESSOR;
1808 		status = acpi_bus_get_status_handle(handle, sta);
1809 		if (ACPI_FAILURE(status))
1810 			return -ENODEV;
1811 		break;
1812 	case ACPI_TYPE_THERMAL:
1813 		*type = ACPI_BUS_TYPE_THERMAL;
1814 		*sta = ACPI_STA_DEFAULT;
1815 		break;
1816 	case ACPI_TYPE_POWER:
1817 		*type = ACPI_BUS_TYPE_POWER;
1818 		*sta = ACPI_STA_DEFAULT;
1819 		break;
1820 	default:
1821 		return -ENODEV;
1822 	}
1823 
1824 	return 0;
1825 }
1826 
1827 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1828 				       char *idstr,
1829 				       const struct acpi_device_id **matchid)
1830 {
1831 	const struct acpi_device_id *devid;
1832 
1833 	for (devid = handler->ids; devid->id[0]; devid++)
1834 		if (!strcmp((char *)devid->id, idstr)) {
1835 			if (matchid)
1836 				*matchid = devid;
1837 
1838 			return true;
1839 		}
1840 
1841 	return false;
1842 }
1843 
1844 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1845 					const struct acpi_device_id **matchid)
1846 {
1847 	struct acpi_scan_handler *handler;
1848 
1849 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1850 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1851 			return handler;
1852 
1853 	return NULL;
1854 }
1855 
1856 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1857 {
1858 	if (!!hotplug->enabled == !!val)
1859 		return;
1860 
1861 	mutex_lock(&acpi_scan_lock);
1862 
1863 	hotplug->enabled = val;
1864 
1865 	mutex_unlock(&acpi_scan_lock);
1866 }
1867 
1868 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1869 {
1870 	struct acpi_device_pnp pnp = {};
1871 	struct acpi_hardware_id *hwid;
1872 	struct acpi_scan_handler *handler;
1873 
1874 	INIT_LIST_HEAD(&pnp.ids);
1875 	acpi_set_pnp_ids(handle, &pnp, type);
1876 
1877 	if (!pnp.type.hardware_id)
1878 		goto out;
1879 
1880 	/*
1881 	 * This relies on the fact that acpi_install_notify_handler() will not
1882 	 * install the same notify handler routine twice for the same handle.
1883 	 */
1884 	list_for_each_entry(hwid, &pnp.ids, list) {
1885 		handler = acpi_scan_match_handler(hwid->id, NULL);
1886 		if (handler) {
1887 			acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1888 					acpi_hotplug_notify_cb, handler);
1889 			break;
1890 		}
1891 	}
1892 
1893 out:
1894 	acpi_free_pnp_ids(&pnp);
1895 }
1896 
1897 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1898 				      void *not_used, void **return_value)
1899 {
1900 	struct acpi_device *device = NULL;
1901 	int type;
1902 	unsigned long long sta;
1903 	acpi_status status;
1904 	int result;
1905 
1906 	acpi_bus_get_device(handle, &device);
1907 	if (device)
1908 		goto out;
1909 
1910 	result = acpi_bus_type_and_status(handle, &type, &sta);
1911 	if (result)
1912 		return AE_OK;
1913 
1914 	if (type == ACPI_BUS_TYPE_POWER) {
1915 		acpi_add_power_resource(handle);
1916 		return AE_OK;
1917 	}
1918 
1919 	acpi_scan_init_hotplug(handle, type);
1920 
1921 	if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1922 	    !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1923 		struct acpi_device_wakeup wakeup;
1924 		acpi_handle temp;
1925 
1926 		status = acpi_get_handle(handle, "_PRW", &temp);
1927 		if (ACPI_SUCCESS(status)) {
1928 			acpi_bus_extract_wakeup_device_power_package(handle,
1929 								     &wakeup);
1930 			acpi_power_resources_list_free(&wakeup.resources);
1931 		}
1932 		return AE_CTRL_DEPTH;
1933 	}
1934 
1935 	acpi_add_single_object(&device, handle, type, sta);
1936 	if (!device)
1937 		return AE_CTRL_DEPTH;
1938 
1939  out:
1940 	if (!*return_value)
1941 		*return_value = device;
1942 
1943 	return AE_OK;
1944 }
1945 
1946 static int acpi_scan_attach_handler(struct acpi_device *device)
1947 {
1948 	struct acpi_hardware_id *hwid;
1949 	int ret = 0;
1950 
1951 	list_for_each_entry(hwid, &device->pnp.ids, list) {
1952 		const struct acpi_device_id *devid;
1953 		struct acpi_scan_handler *handler;
1954 
1955 		handler = acpi_scan_match_handler(hwid->id, &devid);
1956 		if (handler) {
1957 			ret = handler->attach(device, devid);
1958 			if (ret > 0) {
1959 				device->handler = handler;
1960 				break;
1961 			} else if (ret < 0) {
1962 				break;
1963 			}
1964 		}
1965 	}
1966 	return ret;
1967 }
1968 
1969 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1970 					  void *not_used, void **ret_not_used)
1971 {
1972 	struct acpi_device *device;
1973 	unsigned long long sta_not_used;
1974 	int ret;
1975 
1976 	/*
1977 	 * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1978 	 * namespace walks prematurely.
1979 	 */
1980 	if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1981 		return AE_OK;
1982 
1983 	if (acpi_bus_get_device(handle, &device))
1984 		return AE_CTRL_DEPTH;
1985 
1986 	if (device->handler)
1987 		return AE_OK;
1988 
1989 	ret = acpi_scan_attach_handler(device);
1990 	if (ret)
1991 		return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1992 
1993 	ret = device_attach(&device->dev);
1994 	return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1995 }
1996 
1997 /**
1998  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1999  * @handle: Root of the namespace scope to scan.
2000  *
2001  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2002  * found devices.
2003  *
2004  * If no devices were found, -ENODEV is returned, but it does not mean that
2005  * there has been a real error.  There just have been no suitable ACPI objects
2006  * in the table trunk from which the kernel could create a device and add an
2007  * appropriate driver.
2008  *
2009  * Must be called under acpi_scan_lock.
2010  */
2011 int acpi_bus_scan(acpi_handle handle)
2012 {
2013 	void *device = NULL;
2014 	int error = 0;
2015 
2016 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2017 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2018 				    acpi_bus_check_add, NULL, NULL, &device);
2019 
2020 	if (!device)
2021 		error = -ENODEV;
2022 	else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
2023 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2024 				    acpi_bus_device_attach, NULL, NULL, NULL);
2025 
2026 	return error;
2027 }
2028 EXPORT_SYMBOL(acpi_bus_scan);
2029 
2030 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
2031 					  void *not_used, void **ret_not_used)
2032 {
2033 	struct acpi_device *device = NULL;
2034 
2035 	if (!acpi_bus_get_device(handle, &device)) {
2036 		struct acpi_scan_handler *dev_handler = device->handler;
2037 
2038 		if (dev_handler) {
2039 			if (dev_handler->detach)
2040 				dev_handler->detach(device);
2041 
2042 			device->handler = NULL;
2043 		} else {
2044 			device_release_driver(&device->dev);
2045 		}
2046 	}
2047 	return AE_OK;
2048 }
2049 
2050 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
2051 				   void *not_used, void **ret_not_used)
2052 {
2053 	struct acpi_device *device = NULL;
2054 
2055 	if (!acpi_bus_get_device(handle, &device))
2056 		acpi_device_unregister(device);
2057 
2058 	return AE_OK;
2059 }
2060 
2061 /**
2062  * acpi_bus_trim - Remove ACPI device node and all of its descendants
2063  * @start: Root of the ACPI device nodes subtree to remove.
2064  *
2065  * Must be called under acpi_scan_lock.
2066  */
2067 void acpi_bus_trim(struct acpi_device *start)
2068 {
2069 	/*
2070 	 * Execute acpi_bus_device_detach() as a post-order callback to detach
2071 	 * all ACPI drivers from the device nodes being removed.
2072 	 */
2073 	acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2074 			    acpi_bus_device_detach, NULL, NULL);
2075 	acpi_bus_device_detach(start->handle, 0, NULL, NULL);
2076 	/*
2077 	 * Execute acpi_bus_remove() as a post-order callback to remove device
2078 	 * nodes in the given namespace scope.
2079 	 */
2080 	acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2081 			    acpi_bus_remove, NULL, NULL);
2082 	acpi_bus_remove(start->handle, 0, NULL, NULL);
2083 }
2084 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2085 
2086 static int acpi_bus_scan_fixed(void)
2087 {
2088 	int result = 0;
2089 
2090 	/*
2091 	 * Enumerate all fixed-feature devices.
2092 	 */
2093 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2094 		struct acpi_device *device = NULL;
2095 
2096 		result = acpi_add_single_object(&device, NULL,
2097 						ACPI_BUS_TYPE_POWER_BUTTON,
2098 						ACPI_STA_DEFAULT);
2099 		if (result)
2100 			return result;
2101 
2102 		result = device_attach(&device->dev);
2103 		if (result < 0)
2104 			return result;
2105 
2106 		device_init_wakeup(&device->dev, true);
2107 	}
2108 
2109 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2110 		struct acpi_device *device = NULL;
2111 
2112 		result = acpi_add_single_object(&device, NULL,
2113 						ACPI_BUS_TYPE_SLEEP_BUTTON,
2114 						ACPI_STA_DEFAULT);
2115 		if (result)
2116 			return result;
2117 
2118 		result = device_attach(&device->dev);
2119 	}
2120 
2121 	return result < 0 ? result : 0;
2122 }
2123 
2124 int __init acpi_scan_init(void)
2125 {
2126 	int result;
2127 
2128 	result = bus_register(&acpi_bus_type);
2129 	if (result) {
2130 		/* We don't want to quit even if we failed to add suspend/resume */
2131 		printk(KERN_ERR PREFIX "Could not register bus type\n");
2132 	}
2133 
2134 	acpi_pci_root_init();
2135 	acpi_pci_link_init();
2136 	acpi_processor_init();
2137 	acpi_platform_init();
2138 	acpi_lpss_init();
2139 	acpi_cmos_rtc_init();
2140 	acpi_container_init();
2141 	acpi_memory_hotplug_init();
2142 	acpi_dock_init();
2143 
2144 	mutex_lock(&acpi_scan_lock);
2145 	/*
2146 	 * Enumerate devices in the ACPI namespace.
2147 	 */
2148 	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2149 	if (result)
2150 		goto out;
2151 
2152 	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2153 	if (result)
2154 		goto out;
2155 
2156 	result = acpi_bus_scan_fixed();
2157 	if (result) {
2158 		acpi_device_unregister(acpi_root);
2159 		goto out;
2160 	}
2161 
2162 	acpi_update_all_gpes();
2163 
2164 	acpi_pci_root_hp_init();
2165 
2166  out:
2167 	mutex_unlock(&acpi_scan_lock);
2168 	return result;
2169 }
2170