Merge tag 'sunxi-dt-for-3.11-2' of git://github.com/mripard/linux into next/dt
[sfrench/cifs-2.6.git] / drivers / acpi / scan.c
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 static const char *dummy_hid = "device";
31
32 static LIST_HEAD(acpi_device_list);
33 static LIST_HEAD(acpi_bus_id_list);
34 static DEFINE_MUTEX(acpi_scan_lock);
35 static LIST_HEAD(acpi_scan_handlers_list);
36 DEFINE_MUTEX(acpi_device_lock);
37 LIST_HEAD(acpi_wakeup_device_list);
38
39 struct acpi_device_bus_id{
40         char bus_id[15];
41         unsigned int instance_no;
42         struct list_head node;
43 };
44
45 void acpi_scan_lock_acquire(void)
46 {
47         mutex_lock(&acpi_scan_lock);
48 }
49 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
50
51 void acpi_scan_lock_release(void)
52 {
53         mutex_unlock(&acpi_scan_lock);
54 }
55 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
56
57 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
58 {
59         if (!handler || !handler->attach)
60                 return -EINVAL;
61
62         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
63         return 0;
64 }
65
66 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
67                                        const char *hotplug_profile_name)
68 {
69         int error;
70
71         error = acpi_scan_add_handler(handler);
72         if (error)
73                 return error;
74
75         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
76         return 0;
77 }
78
79 /*
80  * Creates hid/cid(s) string needed for modalias and uevent
81  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
82  * char *modalias: "acpi:IBM0001:ACPI0001"
83 */
84 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
85                            int size)
86 {
87         int len;
88         int count;
89         struct acpi_hardware_id *id;
90
91         if (list_empty(&acpi_dev->pnp.ids))
92                 return 0;
93
94         len = snprintf(modalias, size, "acpi:");
95         size -= len;
96
97         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
98                 count = snprintf(&modalias[len], size, "%s:", id->id);
99                 if (count < 0 || count >= size)
100                         return -EINVAL;
101                 len += count;
102                 size -= count;
103         }
104
105         modalias[len] = '\0';
106         return len;
107 }
108
109 static ssize_t
110 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
111         struct acpi_device *acpi_dev = to_acpi_device(dev);
112         int len;
113
114         /* Device has no HID and no CID or string is >1024 */
115         len = create_modalias(acpi_dev, buf, 1024);
116         if (len <= 0)
117                 return 0;
118         buf[len++] = '\n';
119         return len;
120 }
121 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
122
123 static int acpi_scan_hot_remove(struct acpi_device *device)
124 {
125         acpi_handle handle = device->handle;
126         acpi_handle not_used;
127         struct acpi_object_list arg_list;
128         union acpi_object arg;
129         acpi_status status;
130         unsigned long long sta;
131
132         /* If there is no handle, the device node has been unregistered. */
133         if (!handle) {
134                 dev_dbg(&device->dev, "ACPI handle missing\n");
135                 put_device(&device->dev);
136                 return -EINVAL;
137         }
138
139         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
140                 "Hot-removing device %s...\n", dev_name(&device->dev)));
141
142         acpi_bus_trim(device);
143         /* Device node has been unregistered. */
144         put_device(&device->dev);
145         device = NULL;
146
147         if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &not_used))) {
148                 arg_list.count = 1;
149                 arg_list.pointer = &arg;
150                 arg.type = ACPI_TYPE_INTEGER;
151                 arg.integer.value = 0;
152                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
153         }
154
155         arg_list.count = 1;
156         arg_list.pointer = &arg;
157         arg.type = ACPI_TYPE_INTEGER;
158         arg.integer.value = 1;
159
160         /*
161          * TBD: _EJD support.
162          */
163         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
164         if (ACPI_FAILURE(status)) {
165                 if (status == AE_NOT_FOUND) {
166                         return -ENODEV;
167                 } else {
168                         acpi_handle_warn(handle, "Eject failed (0x%x)\n",
169                                                                 status);
170                         return -EIO;
171                 }
172         }
173
174         /*
175          * Verify if eject was indeed successful.  If not, log an error
176          * message.  No need to call _OST since _EJ0 call was made OK.
177          */
178         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
179         if (ACPI_FAILURE(status)) {
180                 acpi_handle_warn(handle,
181                         "Status check after eject failed (0x%x)\n", status);
182         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
183                 acpi_handle_warn(handle,
184                         "Eject incomplete - status 0x%llx\n", sta);
185         }
186
187         return 0;
188 }
189
190 static void acpi_bus_device_eject(void *context)
191 {
192         acpi_handle handle = context;
193         struct acpi_device *device = NULL;
194         struct acpi_scan_handler *handler;
195         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
196
197         mutex_lock(&acpi_scan_lock);
198
199         acpi_bus_get_device(handle, &device);
200         if (!device)
201                 goto err_out;
202
203         handler = device->handler;
204         if (!handler || !handler->hotplug.enabled) {
205                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
206                 goto err_out;
207         }
208         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
209                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
210         if (handler->hotplug.mode == AHM_CONTAINER) {
211                 device->flags.eject_pending = true;
212                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
213         } else {
214                 int error;
215
216                 get_device(&device->dev);
217                 error = acpi_scan_hot_remove(device);
218                 if (error)
219                         goto err_out;
220         }
221
222  out:
223         mutex_unlock(&acpi_scan_lock);
224         return;
225
226  err_out:
227         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
228                                   NULL);
229         goto out;
230 }
231
232 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
233 {
234         struct acpi_device *device = NULL;
235         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
236         int error;
237
238         mutex_lock(&acpi_scan_lock);
239
240         acpi_bus_get_device(handle, &device);
241         if (device) {
242                 dev_warn(&device->dev, "Attempt to re-insert\n");
243                 goto out;
244         }
245         acpi_evaluate_hotplug_ost(handle, ost_source,
246                                   ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
247         error = acpi_bus_scan(handle);
248         if (error) {
249                 acpi_handle_warn(handle, "Namespace scan failure\n");
250                 goto out;
251         }
252         error = acpi_bus_get_device(handle, &device);
253         if (error) {
254                 acpi_handle_warn(handle, "Missing device node object\n");
255                 goto out;
256         }
257         ost_code = ACPI_OST_SC_SUCCESS;
258         if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
259                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
260
261  out:
262         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
263         mutex_unlock(&acpi_scan_lock);
264 }
265
266 static void acpi_scan_bus_check(void *context)
267 {
268         acpi_scan_bus_device_check((acpi_handle)context,
269                                    ACPI_NOTIFY_BUS_CHECK);
270 }
271
272 static void acpi_scan_device_check(void *context)
273 {
274         acpi_scan_bus_device_check((acpi_handle)context,
275                                    ACPI_NOTIFY_DEVICE_CHECK);
276 }
277
278 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
279 {
280         u32 ost_status;
281
282         switch (type) {
283         case ACPI_NOTIFY_BUS_CHECK:
284                 acpi_handle_debug(handle,
285                         "ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
286                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
287                 break;
288         case ACPI_NOTIFY_DEVICE_CHECK:
289                 acpi_handle_debug(handle,
290                         "ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
291                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
292                 break;
293         case ACPI_NOTIFY_EJECT_REQUEST:
294                 acpi_handle_debug(handle,
295                         "ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
296                 ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
297                 break;
298         default:
299                 /* non-hotplug event; possibly handled by other handler */
300                 return;
301         }
302
303         acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
304 }
305
306 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
307 {
308         acpi_osd_exec_callback callback;
309         struct acpi_scan_handler *handler = data;
310         acpi_status status;
311
312         if (!handler->hotplug.enabled)
313                 return acpi_hotplug_unsupported(handle, type);
314
315         switch (type) {
316         case ACPI_NOTIFY_BUS_CHECK:
317                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
318                 callback = acpi_scan_bus_check;
319                 break;
320         case ACPI_NOTIFY_DEVICE_CHECK:
321                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
322                 callback = acpi_scan_device_check;
323                 break;
324         case ACPI_NOTIFY_EJECT_REQUEST:
325                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
326                 callback = acpi_bus_device_eject;
327                 break;
328         default:
329                 /* non-hotplug event; possibly handled by other handler */
330                 return;
331         }
332         status = acpi_os_hotplug_execute(callback, handle);
333         if (ACPI_FAILURE(status))
334                 acpi_evaluate_hotplug_ost(handle, type,
335                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
336                                           NULL);
337 }
338
339 /**
340  * acpi_bus_hot_remove_device: hot-remove a device and its children
341  * @context: struct acpi_eject_event pointer (freed in this func)
342  *
343  * Hot-remove a device and its children. This function frees up the
344  * memory space passed by arg context, so that the caller may call
345  * this function asynchronously through acpi_os_hotplug_execute().
346  */
347 void acpi_bus_hot_remove_device(void *context)
348 {
349         struct acpi_eject_event *ej_event = context;
350         struct acpi_device *device = ej_event->device;
351         acpi_handle handle = device->handle;
352         int error;
353
354         mutex_lock(&acpi_scan_lock);
355
356         error = acpi_scan_hot_remove(device);
357         if (error && handle)
358                 acpi_evaluate_hotplug_ost(handle, ej_event->event,
359                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
360                                           NULL);
361
362         mutex_unlock(&acpi_scan_lock);
363         kfree(context);
364 }
365 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
366
367 static ssize_t real_power_state_show(struct device *dev,
368                                      struct device_attribute *attr, char *buf)
369 {
370         struct acpi_device *adev = to_acpi_device(dev);
371         int state;
372         int ret;
373
374         ret = acpi_device_get_power(adev, &state);
375         if (ret)
376                 return ret;
377
378         return sprintf(buf, "%s\n", acpi_power_state_string(state));
379 }
380
381 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
382
383 static ssize_t power_state_show(struct device *dev,
384                                 struct device_attribute *attr, char *buf)
385 {
386         struct acpi_device *adev = to_acpi_device(dev);
387
388         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
389 }
390
391 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
392
393 static ssize_t
394 acpi_eject_store(struct device *d, struct device_attribute *attr,
395                 const char *buf, size_t count)
396 {
397         struct acpi_device *acpi_device = to_acpi_device(d);
398         struct acpi_eject_event *ej_event;
399         acpi_object_type not_used;
400         acpi_status status;
401         u32 ost_source;
402         int ret;
403
404         if (!count || buf[0] != '1')
405                 return -EINVAL;
406
407         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
408             && !acpi_device->driver)
409                 return -ENODEV;
410
411         status = acpi_get_type(acpi_device->handle, &not_used);
412         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
413                 return -ENODEV;
414
415         mutex_lock(&acpi_scan_lock);
416
417         if (acpi_device->flags.eject_pending) {
418                 /* ACPI eject notification event. */
419                 ost_source = ACPI_NOTIFY_EJECT_REQUEST;
420                 acpi_device->flags.eject_pending = 0;
421         } else {
422                 /* Eject initiated by user space. */
423                 ost_source = ACPI_OST_EC_OSPM_EJECT;
424         }
425         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
426         if (!ej_event) {
427                 ret = -ENOMEM;
428                 goto err_out;
429         }
430         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
431                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
432         ej_event->device = acpi_device;
433         ej_event->event = ost_source;
434         get_device(&acpi_device->dev);
435         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
436         if (ACPI_FAILURE(status)) {
437                 put_device(&acpi_device->dev);
438                 kfree(ej_event);
439                 ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
440                 goto err_out;
441         }
442         ret = count;
443
444  out:
445         mutex_unlock(&acpi_scan_lock);
446         return ret;
447
448  err_out:
449         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
450                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
451         goto out;
452 }
453
454 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
455
456 static ssize_t
457 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
458         struct acpi_device *acpi_dev = to_acpi_device(dev);
459
460         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
461 }
462 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
463
464 static ssize_t acpi_device_uid_show(struct device *dev,
465                                     struct device_attribute *attr, char *buf)
466 {
467         struct acpi_device *acpi_dev = to_acpi_device(dev);
468
469         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
470 }
471 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
472
473 static ssize_t acpi_device_adr_show(struct device *dev,
474                                     struct device_attribute *attr, char *buf)
475 {
476         struct acpi_device *acpi_dev = to_acpi_device(dev);
477
478         return sprintf(buf, "0x%08x\n",
479                        (unsigned int)(acpi_dev->pnp.bus_address));
480 }
481 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
482
483 static ssize_t
484 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
485         struct acpi_device *acpi_dev = to_acpi_device(dev);
486         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
487         int result;
488
489         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
490         if (result)
491                 goto end;
492
493         result = sprintf(buf, "%s\n", (char*)path.pointer);
494         kfree(path.pointer);
495 end:
496         return result;
497 }
498 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
499
500 /* sysfs file that shows description text from the ACPI _STR method */
501 static ssize_t description_show(struct device *dev,
502                                 struct device_attribute *attr,
503                                 char *buf) {
504         struct acpi_device *acpi_dev = to_acpi_device(dev);
505         int result;
506
507         if (acpi_dev->pnp.str_obj == NULL)
508                 return 0;
509
510         /*
511          * The _STR object contains a Unicode identifier for a device.
512          * We need to convert to utf-8 so it can be displayed.
513          */
514         result = utf16s_to_utf8s(
515                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
516                 acpi_dev->pnp.str_obj->buffer.length,
517                 UTF16_LITTLE_ENDIAN, buf,
518                 PAGE_SIZE);
519
520         buf[result++] = '\n';
521
522         return result;
523 }
524 static DEVICE_ATTR(description, 0444, description_show, NULL);
525
526 static ssize_t
527 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
528                      char *buf) {
529         struct acpi_device *acpi_dev = to_acpi_device(dev);
530
531         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
532 }
533 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
534
535 static int acpi_device_setup_files(struct acpi_device *dev)
536 {
537         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
538         acpi_status status;
539         acpi_handle temp;
540         unsigned long long sun;
541         int result = 0;
542
543         /*
544          * Devices gotten from FADT don't have a "path" attribute
545          */
546         if (dev->handle) {
547                 result = device_create_file(&dev->dev, &dev_attr_path);
548                 if (result)
549                         goto end;
550         }
551
552         if (!list_empty(&dev->pnp.ids)) {
553                 result = device_create_file(&dev->dev, &dev_attr_hid);
554                 if (result)
555                         goto end;
556
557                 result = device_create_file(&dev->dev, &dev_attr_modalias);
558                 if (result)
559                         goto end;
560         }
561
562         /*
563          * If device has _STR, 'description' file is created
564          */
565         status = acpi_get_handle(dev->handle, "_STR", &temp);
566         if (ACPI_SUCCESS(status)) {
567                 status = acpi_evaluate_object(dev->handle, "_STR",
568                                         NULL, &buffer);
569                 if (ACPI_FAILURE(status))
570                         buffer.pointer = NULL;
571                 dev->pnp.str_obj = buffer.pointer;
572                 result = device_create_file(&dev->dev, &dev_attr_description);
573                 if (result)
574                         goto end;
575         }
576
577         if (dev->pnp.type.bus_address)
578                 result = device_create_file(&dev->dev, &dev_attr_adr);
579         if (dev->pnp.unique_id)
580                 result = device_create_file(&dev->dev, &dev_attr_uid);
581
582         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
583         if (ACPI_SUCCESS(status)) {
584                 dev->pnp.sun = (unsigned long)sun;
585                 result = device_create_file(&dev->dev, &dev_attr_sun);
586                 if (result)
587                         goto end;
588         } else {
589                 dev->pnp.sun = (unsigned long)-1;
590         }
591
592         /*
593          * If device has _EJ0, 'eject' file is created that is used to trigger
594          * hot-removal function from userland.
595          */
596         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
597         if (ACPI_SUCCESS(status)) {
598                 result = device_create_file(&dev->dev, &dev_attr_eject);
599                 if (result)
600                         return result;
601         }
602
603         if (dev->flags.power_manageable) {
604                 result = device_create_file(&dev->dev, &dev_attr_power_state);
605                 if (result)
606                         return result;
607
608                 if (dev->power.flags.power_resources)
609                         result = device_create_file(&dev->dev,
610                                                     &dev_attr_real_power_state);
611         }
612
613 end:
614         return result;
615 }
616
617 static void acpi_device_remove_files(struct acpi_device *dev)
618 {
619         acpi_status status;
620         acpi_handle temp;
621
622         if (dev->flags.power_manageable) {
623                 device_remove_file(&dev->dev, &dev_attr_power_state);
624                 if (dev->power.flags.power_resources)
625                         device_remove_file(&dev->dev,
626                                            &dev_attr_real_power_state);
627         }
628
629         /*
630          * If device has _STR, remove 'description' file
631          */
632         status = acpi_get_handle(dev->handle, "_STR", &temp);
633         if (ACPI_SUCCESS(status)) {
634                 kfree(dev->pnp.str_obj);
635                 device_remove_file(&dev->dev, &dev_attr_description);
636         }
637         /*
638          * If device has _EJ0, remove 'eject' file.
639          */
640         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
641         if (ACPI_SUCCESS(status))
642                 device_remove_file(&dev->dev, &dev_attr_eject);
643
644         status = acpi_get_handle(dev->handle, "_SUN", &temp);
645         if (ACPI_SUCCESS(status))
646                 device_remove_file(&dev->dev, &dev_attr_sun);
647
648         if (dev->pnp.unique_id)
649                 device_remove_file(&dev->dev, &dev_attr_uid);
650         if (dev->pnp.type.bus_address)
651                 device_remove_file(&dev->dev, &dev_attr_adr);
652         device_remove_file(&dev->dev, &dev_attr_modalias);
653         device_remove_file(&dev->dev, &dev_attr_hid);
654         if (dev->handle)
655                 device_remove_file(&dev->dev, &dev_attr_path);
656 }
657 /* --------------------------------------------------------------------------
658                         ACPI Bus operations
659    -------------------------------------------------------------------------- */
660
661 static const struct acpi_device_id *__acpi_match_device(
662         struct acpi_device *device, const struct acpi_device_id *ids)
663 {
664         const struct acpi_device_id *id;
665         struct acpi_hardware_id *hwid;
666
667         /*
668          * If the device is not present, it is unnecessary to load device
669          * driver for it.
670          */
671         if (!device->status.present)
672                 return NULL;
673
674         for (id = ids; id->id[0]; id++)
675                 list_for_each_entry(hwid, &device->pnp.ids, list)
676                         if (!strcmp((char *) id->id, hwid->id))
677                                 return id;
678
679         return NULL;
680 }
681
682 /**
683  * acpi_match_device - Match a struct device against a given list of ACPI IDs
684  * @ids: Array of struct acpi_device_id object to match against.
685  * @dev: The device structure to match.
686  *
687  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
688  * object for that handle and use that object to match against a given list of
689  * device IDs.
690  *
691  * Return a pointer to the first matching ID on success or %NULL on failure.
692  */
693 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
694                                                const struct device *dev)
695 {
696         struct acpi_device *adev;
697         acpi_handle handle = ACPI_HANDLE(dev);
698
699         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
700                 return NULL;
701
702         return __acpi_match_device(adev, ids);
703 }
704 EXPORT_SYMBOL_GPL(acpi_match_device);
705
706 int acpi_match_device_ids(struct acpi_device *device,
707                           const struct acpi_device_id *ids)
708 {
709         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
710 }
711 EXPORT_SYMBOL(acpi_match_device_ids);
712
713 static void acpi_free_power_resources_lists(struct acpi_device *device)
714 {
715         int i;
716
717         if (device->wakeup.flags.valid)
718                 acpi_power_resources_list_free(&device->wakeup.resources);
719
720         if (!device->flags.power_manageable)
721                 return;
722
723         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
724                 struct acpi_device_power_state *ps = &device->power.states[i];
725                 acpi_power_resources_list_free(&ps->resources);
726         }
727 }
728
729 static void acpi_device_release(struct device *dev)
730 {
731         struct acpi_device *acpi_dev = to_acpi_device(dev);
732
733         acpi_free_pnp_ids(&acpi_dev->pnp);
734         acpi_free_power_resources_lists(acpi_dev);
735         kfree(acpi_dev);
736 }
737
738 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
739 {
740         struct acpi_device *acpi_dev = to_acpi_device(dev);
741         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
742
743         return acpi_dev->flags.match_driver
744                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
745 }
746
747 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
748 {
749         struct acpi_device *acpi_dev = to_acpi_device(dev);
750         int len;
751
752         if (list_empty(&acpi_dev->pnp.ids))
753                 return 0;
754
755         if (add_uevent_var(env, "MODALIAS="))
756                 return -ENOMEM;
757         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
758                               sizeof(env->buf) - env->buflen);
759         if (len >= (sizeof(env->buf) - env->buflen))
760                 return -ENOMEM;
761         env->buflen += len;
762         return 0;
763 }
764
765 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
766 {
767         struct acpi_device *device = data;
768
769         device->driver->ops.notify(device, event);
770 }
771
772 static acpi_status acpi_device_notify_fixed(void *data)
773 {
774         struct acpi_device *device = data;
775
776         /* Fixed hardware devices have no handles */
777         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
778         return AE_OK;
779 }
780
781 static int acpi_device_install_notify_handler(struct acpi_device *device)
782 {
783         acpi_status status;
784
785         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
786                 status =
787                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
788                                                      acpi_device_notify_fixed,
789                                                      device);
790         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
791                 status =
792                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
793                                                      acpi_device_notify_fixed,
794                                                      device);
795         else
796                 status = acpi_install_notify_handler(device->handle,
797                                                      ACPI_DEVICE_NOTIFY,
798                                                      acpi_device_notify,
799                                                      device);
800
801         if (ACPI_FAILURE(status))
802                 return -EINVAL;
803         return 0;
804 }
805
806 static void acpi_device_remove_notify_handler(struct acpi_device *device)
807 {
808         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
809                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
810                                                 acpi_device_notify_fixed);
811         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
812                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
813                                                 acpi_device_notify_fixed);
814         else
815                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
816                                            acpi_device_notify);
817 }
818
819 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
820 static int acpi_device_probe(struct device * dev)
821 {
822         struct acpi_device *acpi_dev = to_acpi_device(dev);
823         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
824         int ret;
825
826         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
827         if (!ret) {
828                 if (acpi_drv->ops.notify) {
829                         ret = acpi_device_install_notify_handler(acpi_dev);
830                         if (ret) {
831                                 if (acpi_drv->ops.remove)
832                                         acpi_drv->ops.remove(acpi_dev);
833                                 acpi_dev->driver = NULL;
834                                 acpi_dev->driver_data = NULL;
835                                 return ret;
836                         }
837                 }
838
839                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
840                         "Found driver [%s] for device [%s]\n",
841                         acpi_drv->name, acpi_dev->pnp.bus_id));
842                 get_device(dev);
843         }
844         return ret;
845 }
846
847 static int acpi_device_remove(struct device * dev)
848 {
849         struct acpi_device *acpi_dev = to_acpi_device(dev);
850         struct acpi_driver *acpi_drv = acpi_dev->driver;
851
852         if (acpi_drv) {
853                 if (acpi_drv->ops.notify)
854                         acpi_device_remove_notify_handler(acpi_dev);
855                 if (acpi_drv->ops.remove)
856                         acpi_drv->ops.remove(acpi_dev);
857         }
858         acpi_dev->driver = NULL;
859         acpi_dev->driver_data = NULL;
860
861         put_device(dev);
862         return 0;
863 }
864
865 struct bus_type acpi_bus_type = {
866         .name           = "acpi",
867         .match          = acpi_bus_match,
868         .probe          = acpi_device_probe,
869         .remove         = acpi_device_remove,
870         .uevent         = acpi_device_uevent,
871 };
872
873 int acpi_device_add(struct acpi_device *device,
874                     void (*release)(struct device *))
875 {
876         int result;
877         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
878         int found = 0;
879
880         if (device->handle) {
881                 acpi_status status;
882
883                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
884                                           device);
885                 if (ACPI_FAILURE(status)) {
886                         acpi_handle_err(device->handle,
887                                         "Unable to attach device data\n");
888                         return -ENODEV;
889                 }
890         }
891
892         /*
893          * Linkage
894          * -------
895          * Link this device to its parent and siblings.
896          */
897         INIT_LIST_HEAD(&device->children);
898         INIT_LIST_HEAD(&device->node);
899         INIT_LIST_HEAD(&device->wakeup_list);
900         INIT_LIST_HEAD(&device->physical_node_list);
901         mutex_init(&device->physical_node_lock);
902         INIT_LIST_HEAD(&device->power_dependent);
903
904         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
905         if (!new_bus_id) {
906                 pr_err(PREFIX "Memory allocation error\n");
907                 result = -ENOMEM;
908                 goto err_detach;
909         }
910
911         mutex_lock(&acpi_device_lock);
912         /*
913          * Find suitable bus_id and instance number in acpi_bus_id_list
914          * If failed, create one and link it into acpi_bus_id_list
915          */
916         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
917                 if (!strcmp(acpi_device_bus_id->bus_id,
918                             acpi_device_hid(device))) {
919                         acpi_device_bus_id->instance_no++;
920                         found = 1;
921                         kfree(new_bus_id);
922                         break;
923                 }
924         }
925         if (!found) {
926                 acpi_device_bus_id = new_bus_id;
927                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
928                 acpi_device_bus_id->instance_no = 0;
929                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
930         }
931         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
932
933         if (device->parent)
934                 list_add_tail(&device->node, &device->parent->children);
935
936         if (device->wakeup.flags.valid)
937                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
938         mutex_unlock(&acpi_device_lock);
939
940         if (device->parent)
941                 device->dev.parent = &device->parent->dev;
942         device->dev.bus = &acpi_bus_type;
943         device->dev.release = release;
944         result = device_add(&device->dev);
945         if (result) {
946                 dev_err(&device->dev, "Error registering device\n");
947                 goto err;
948         }
949
950         result = acpi_device_setup_files(device);
951         if (result)
952                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
953                        dev_name(&device->dev));
954
955         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
956         return 0;
957
958  err:
959         mutex_lock(&acpi_device_lock);
960         if (device->parent)
961                 list_del(&device->node);
962         list_del(&device->wakeup_list);
963         mutex_unlock(&acpi_device_lock);
964
965  err_detach:
966         acpi_detach_data(device->handle, acpi_bus_data_handler);
967         return result;
968 }
969
970 static void acpi_device_unregister(struct acpi_device *device)
971 {
972         mutex_lock(&acpi_device_lock);
973         if (device->parent)
974                 list_del(&device->node);
975
976         list_del(&device->wakeup_list);
977         mutex_unlock(&acpi_device_lock);
978
979         acpi_detach_data(device->handle, acpi_bus_data_handler);
980
981         acpi_power_add_remove_device(device, false);
982         acpi_device_remove_files(device);
983         if (device->remove)
984                 device->remove(device);
985
986         device_del(&device->dev);
987         /*
988          * Transition the device to D3cold to drop the reference counts of all
989          * power resources the device depends on and turn off the ones that have
990          * no more references.
991          */
992         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
993         device->handle = NULL;
994         put_device(&device->dev);
995 }
996
997 /* --------------------------------------------------------------------------
998                                  Driver Management
999    -------------------------------------------------------------------------- */
1000 /**
1001  * acpi_bus_driver_init - add a device to a driver
1002  * @device: the device to add and initialize
1003  * @driver: driver for the device
1004  *
1005  * Used to initialize a device via its device driver.  Called whenever a
1006  * driver is bound to a device.  Invokes the driver's add() ops.
1007  */
1008 static int
1009 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
1010 {
1011         int result = 0;
1012
1013         if (!device || !driver)
1014                 return -EINVAL;
1015
1016         if (!driver->ops.add)
1017                 return -ENOSYS;
1018
1019         result = driver->ops.add(device);
1020         if (result)
1021                 return result;
1022
1023         device->driver = driver;
1024
1025         /*
1026          * TBD - Configuration Management: Assign resources to device based
1027          * upon possible configuration and currently allocated resources.
1028          */
1029
1030         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1031                           "Driver successfully bound to device\n"));
1032         return 0;
1033 }
1034
1035 /**
1036  * acpi_bus_register_driver - register a driver with the ACPI bus
1037  * @driver: driver being registered
1038  *
1039  * Registers a driver with the ACPI bus.  Searches the namespace for all
1040  * devices that match the driver's criteria and binds.  Returns zero for
1041  * success or a negative error status for failure.
1042  */
1043 int acpi_bus_register_driver(struct acpi_driver *driver)
1044 {
1045         int ret;
1046
1047         if (acpi_disabled)
1048                 return -ENODEV;
1049         driver->drv.name = driver->name;
1050         driver->drv.bus = &acpi_bus_type;
1051         driver->drv.owner = driver->owner;
1052
1053         ret = driver_register(&driver->drv);
1054         return ret;
1055 }
1056
1057 EXPORT_SYMBOL(acpi_bus_register_driver);
1058
1059 /**
1060  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1061  * @driver: driver to unregister
1062  *
1063  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1064  * devices that match the driver's criteria and unbinds.
1065  */
1066 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1067 {
1068         driver_unregister(&driver->drv);
1069 }
1070
1071 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1072
1073 /* --------------------------------------------------------------------------
1074                                  Device Enumeration
1075    -------------------------------------------------------------------------- */
1076 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1077 {
1078         struct acpi_device *device = NULL;
1079         acpi_status status;
1080
1081         /*
1082          * Fixed hardware devices do not appear in the namespace and do not
1083          * have handles, but we fabricate acpi_devices for them, so we have
1084          * to deal with them specially.
1085          */
1086         if (!handle)
1087                 return acpi_root;
1088
1089         do {
1090                 status = acpi_get_parent(handle, &handle);
1091                 if (ACPI_FAILURE(status))
1092                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1093         } while (acpi_bus_get_device(handle, &device));
1094         return device;
1095 }
1096
1097 acpi_status
1098 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1099 {
1100         acpi_status status;
1101         acpi_handle tmp;
1102         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1103         union acpi_object *obj;
1104
1105         status = acpi_get_handle(handle, "_EJD", &tmp);
1106         if (ACPI_FAILURE(status))
1107                 return status;
1108
1109         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1110         if (ACPI_SUCCESS(status)) {
1111                 obj = buffer.pointer;
1112                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1113                                          ejd);
1114                 kfree(buffer.pointer);
1115         }
1116         return status;
1117 }
1118 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1119
1120 void acpi_bus_data_handler(acpi_handle handle, void *context)
1121 {
1122
1123         /* TBD */
1124
1125         return;
1126 }
1127
1128 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1129                                         struct acpi_device_wakeup *wakeup)
1130 {
1131         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1132         union acpi_object *package = NULL;
1133         union acpi_object *element = NULL;
1134         acpi_status status;
1135         int err = -ENODATA;
1136
1137         if (!wakeup)
1138                 return -EINVAL;
1139
1140         INIT_LIST_HEAD(&wakeup->resources);
1141
1142         /* _PRW */
1143         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1144         if (ACPI_FAILURE(status)) {
1145                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1146                 return err;
1147         }
1148
1149         package = (union acpi_object *)buffer.pointer;
1150
1151         if (!package || package->package.count < 2)
1152                 goto out;
1153
1154         element = &(package->package.elements[0]);
1155         if (!element)
1156                 goto out;
1157
1158         if (element->type == ACPI_TYPE_PACKAGE) {
1159                 if ((element->package.count < 2) ||
1160                     (element->package.elements[0].type !=
1161                      ACPI_TYPE_LOCAL_REFERENCE)
1162                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1163                         goto out;
1164
1165                 wakeup->gpe_device =
1166                     element->package.elements[0].reference.handle;
1167                 wakeup->gpe_number =
1168                     (u32) element->package.elements[1].integer.value;
1169         } else if (element->type == ACPI_TYPE_INTEGER) {
1170                 wakeup->gpe_device = NULL;
1171                 wakeup->gpe_number = element->integer.value;
1172         } else {
1173                 goto out;
1174         }
1175
1176         element = &(package->package.elements[1]);
1177         if (element->type != ACPI_TYPE_INTEGER)
1178                 goto out;
1179
1180         wakeup->sleep_state = element->integer.value;
1181
1182         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1183         if (err)
1184                 goto out;
1185
1186         if (!list_empty(&wakeup->resources)) {
1187                 int sleep_state;
1188
1189                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1190                                                   &sleep_state);
1191                 if (err) {
1192                         acpi_handle_warn(handle, "Retrieving current states "
1193                                          "of wakeup power resources failed\n");
1194                         acpi_power_resources_list_free(&wakeup->resources);
1195                         goto out;
1196                 }
1197                 if (sleep_state < wakeup->sleep_state) {
1198                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1199                                          "(S%d) by S%d from power resources\n",
1200                                          (int)wakeup->sleep_state, sleep_state);
1201                         wakeup->sleep_state = sleep_state;
1202                 }
1203         }
1204         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1205
1206  out:
1207         kfree(buffer.pointer);
1208         return err;
1209 }
1210
1211 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1212 {
1213         struct acpi_device_id button_device_ids[] = {
1214                 {"PNP0C0C", 0},
1215                 {"PNP0C0D", 0},
1216                 {"PNP0C0E", 0},
1217                 {"", 0},
1218         };
1219         acpi_status status;
1220         acpi_event_status event_status;
1221
1222         device->wakeup.flags.notifier_present = 0;
1223
1224         /* Power button, Lid switch always enable wakeup */
1225         if (!acpi_match_device_ids(device, button_device_ids)) {
1226                 device->wakeup.flags.run_wake = 1;
1227                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1228                         /* Do not use Lid/sleep button for S5 wakeup */
1229                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1230                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1231                 }
1232                 device_set_wakeup_capable(&device->dev, true);
1233                 return;
1234         }
1235
1236         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1237                                         device->wakeup.gpe_number,
1238                                                 &event_status);
1239         if (status == AE_OK)
1240                 device->wakeup.flags.run_wake =
1241                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1242 }
1243
1244 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1245 {
1246         acpi_handle temp;
1247         acpi_status status = 0;
1248         int err;
1249
1250         /* Presence of _PRW indicates wake capable */
1251         status = acpi_get_handle(device->handle, "_PRW", &temp);
1252         if (ACPI_FAILURE(status))
1253                 return;
1254
1255         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1256                                                            &device->wakeup);
1257         if (err) {
1258                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1259                 return;
1260         }
1261
1262         device->wakeup.flags.valid = 1;
1263         device->wakeup.prepare_count = 0;
1264         acpi_bus_set_run_wake_flags(device);
1265         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1266          * system for the ACPI device with the _PRW object.
1267          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1268          * So it is necessary to call _DSW object first. Only when it is not
1269          * present will the _PSW object used.
1270          */
1271         err = acpi_device_sleep_wake(device, 0, 0, 0);
1272         if (err)
1273                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1274                                 "error in _DSW or _PSW evaluation\n"));
1275 }
1276
1277 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1278 {
1279         struct acpi_device_power_state *ps = &device->power.states[state];
1280         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1281         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1282         acpi_handle handle;
1283         acpi_status status;
1284
1285         INIT_LIST_HEAD(&ps->resources);
1286
1287         /* Evaluate "_PRx" to get referenced power resources */
1288         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1289         if (ACPI_SUCCESS(status)) {
1290                 union acpi_object *package = buffer.pointer;
1291
1292                 if (buffer.length && package
1293                     && package->type == ACPI_TYPE_PACKAGE
1294                     && package->package.count) {
1295                         int err = acpi_extract_power_resources(package, 0,
1296                                                                &ps->resources);
1297                         if (!err)
1298                                 device->power.flags.power_resources = 1;
1299                 }
1300                 ACPI_FREE(buffer.pointer);
1301         }
1302
1303         /* Evaluate "_PSx" to see if we can do explicit sets */
1304         pathname[2] = 'S';
1305         status = acpi_get_handle(device->handle, pathname, &handle);
1306         if (ACPI_SUCCESS(status))
1307                 ps->flags.explicit_set = 1;
1308
1309         /*
1310          * State is valid if there are means to put the device into it.
1311          * D3hot is only valid if _PR3 present.
1312          */
1313         if (!list_empty(&ps->resources)
1314             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1315                 ps->flags.valid = 1;
1316                 ps->flags.os_accessible = 1;
1317         }
1318
1319         ps->power = -1;         /* Unknown - driver assigned */
1320         ps->latency = -1;       /* Unknown - driver assigned */
1321 }
1322
1323 static void acpi_bus_get_power_flags(struct acpi_device *device)
1324 {
1325         acpi_status status;
1326         acpi_handle handle;
1327         u32 i;
1328
1329         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1330         status = acpi_get_handle(device->handle, "_PS0", &handle);
1331         if (ACPI_FAILURE(status)) {
1332                 status = acpi_get_handle(device->handle, "_PR0", &handle);
1333                 if (ACPI_FAILURE(status))
1334                         return;
1335         }
1336
1337         device->flags.power_manageable = 1;
1338
1339         /*
1340          * Power Management Flags
1341          */
1342         status = acpi_get_handle(device->handle, "_PSC", &handle);
1343         if (ACPI_SUCCESS(status))
1344                 device->power.flags.explicit_get = 1;
1345         status = acpi_get_handle(device->handle, "_IRC", &handle);
1346         if (ACPI_SUCCESS(status))
1347                 device->power.flags.inrush_current = 1;
1348
1349         /*
1350          * Enumerate supported power management states
1351          */
1352         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1353                 acpi_bus_init_power_state(device, i);
1354
1355         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1356
1357         /* Set defaults for D0 and D3 states (always valid) */
1358         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1359         device->power.states[ACPI_STATE_D0].power = 100;
1360         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1361         device->power.states[ACPI_STATE_D3].power = 0;
1362
1363         /* Set D3cold's explicit_set flag if _PS3 exists. */
1364         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1365                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1366
1367         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1368         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1369                         device->power.flags.power_resources)
1370                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1371
1372         if (acpi_bus_init_power(device)) {
1373                 acpi_free_power_resources_lists(device);
1374                 device->flags.power_manageable = 0;
1375         }
1376 }
1377
1378 static void acpi_bus_get_flags(struct acpi_device *device)
1379 {
1380         acpi_status status = AE_OK;
1381         acpi_handle temp = NULL;
1382
1383         /* Presence of _STA indicates 'dynamic_status' */
1384         status = acpi_get_handle(device->handle, "_STA", &temp);
1385         if (ACPI_SUCCESS(status))
1386                 device->flags.dynamic_status = 1;
1387
1388         /* Presence of _RMV indicates 'removable' */
1389         status = acpi_get_handle(device->handle, "_RMV", &temp);
1390         if (ACPI_SUCCESS(status))
1391                 device->flags.removable = 1;
1392
1393         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1394         status = acpi_get_handle(device->handle, "_EJD", &temp);
1395         if (ACPI_SUCCESS(status))
1396                 device->flags.ejectable = 1;
1397         else {
1398                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1399                 if (ACPI_SUCCESS(status))
1400                         device->flags.ejectable = 1;
1401         }
1402 }
1403
1404 static void acpi_device_get_busid(struct acpi_device *device)
1405 {
1406         char bus_id[5] = { '?', 0 };
1407         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1408         int i = 0;
1409
1410         /*
1411          * Bus ID
1412          * ------
1413          * The device's Bus ID is simply the object name.
1414          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1415          */
1416         if (ACPI_IS_ROOT_DEVICE(device)) {
1417                 strcpy(device->pnp.bus_id, "ACPI");
1418                 return;
1419         }
1420
1421         switch (device->device_type) {
1422         case ACPI_BUS_TYPE_POWER_BUTTON:
1423                 strcpy(device->pnp.bus_id, "PWRF");
1424                 break;
1425         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1426                 strcpy(device->pnp.bus_id, "SLPF");
1427                 break;
1428         default:
1429                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1430                 /* Clean up trailing underscores (if any) */
1431                 for (i = 3; i > 1; i--) {
1432                         if (bus_id[i] == '_')
1433                                 bus_id[i] = '\0';
1434                         else
1435                                 break;
1436                 }
1437                 strcpy(device->pnp.bus_id, bus_id);
1438                 break;
1439         }
1440 }
1441
1442 /*
1443  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1444  *
1445  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1446  * then we can safely call it an ejectable drive bay
1447  */
1448 static int acpi_bay_match(acpi_handle handle)
1449 {
1450         acpi_status status;
1451         acpi_handle tmp;
1452         acpi_handle phandle;
1453
1454         status = acpi_get_handle(handle, "_EJ0", &tmp);
1455         if (ACPI_FAILURE(status))
1456                 return -ENODEV;
1457
1458         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1459                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1460                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1461                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1462                 return 0;
1463
1464         if (acpi_get_parent(handle, &phandle))
1465                 return -ENODEV;
1466
1467         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1468                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1469                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1470                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1471                 return 0;
1472
1473         return -ENODEV;
1474 }
1475
1476 /*
1477  * acpi_dock_match - see if an acpi object has a _DCK method
1478  */
1479 static int acpi_dock_match(acpi_handle handle)
1480 {
1481         acpi_handle tmp;
1482         return acpi_get_handle(handle, "_DCK", &tmp);
1483 }
1484
1485 const char *acpi_device_hid(struct acpi_device *device)
1486 {
1487         struct acpi_hardware_id *hid;
1488
1489         if (list_empty(&device->pnp.ids))
1490                 return dummy_hid;
1491
1492         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1493         return hid->id;
1494 }
1495 EXPORT_SYMBOL(acpi_device_hid);
1496
1497 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1498 {
1499         struct acpi_hardware_id *id;
1500
1501         id = kmalloc(sizeof(*id), GFP_KERNEL);
1502         if (!id)
1503                 return;
1504
1505         id->id = kstrdup(dev_id, GFP_KERNEL);
1506         if (!id->id) {
1507                 kfree(id);
1508                 return;
1509         }
1510
1511         list_add_tail(&id->list, &pnp->ids);
1512         pnp->type.hardware_id = 1;
1513 }
1514
1515 /*
1516  * Old IBM workstations have a DSDT bug wherein the SMBus object
1517  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1518  * prefix.  Work around this.
1519  */
1520 static int acpi_ibm_smbus_match(acpi_handle handle)
1521 {
1522         acpi_handle h_dummy;
1523         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1524         int result;
1525
1526         if (!dmi_name_in_vendors("IBM"))
1527                 return -ENODEV;
1528
1529         /* Look for SMBS object */
1530         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1531         if (result)
1532                 return result;
1533
1534         if (strcmp("SMBS", path.pointer)) {
1535                 result = -ENODEV;
1536                 goto out;
1537         }
1538
1539         /* Does it have the necessary (but misnamed) methods? */
1540         result = -ENODEV;
1541         if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1542             ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1543             ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1544                 result = 0;
1545 out:
1546         kfree(path.pointer);
1547         return result;
1548 }
1549
1550 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1551                                 int device_type)
1552 {
1553         acpi_status status;
1554         struct acpi_device_info *info;
1555         struct acpi_pnp_device_id_list *cid_list;
1556         int i;
1557
1558         switch (device_type) {
1559         case ACPI_BUS_TYPE_DEVICE:
1560                 if (handle == ACPI_ROOT_OBJECT) {
1561                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1562                         break;
1563                 }
1564
1565                 status = acpi_get_object_info(handle, &info);
1566                 if (ACPI_FAILURE(status)) {
1567                         pr_err(PREFIX "%s: Error reading device info\n",
1568                                         __func__);
1569                         return;
1570                 }
1571
1572                 if (info->valid & ACPI_VALID_HID)
1573                         acpi_add_id(pnp, info->hardware_id.string);
1574                 if (info->valid & ACPI_VALID_CID) {
1575                         cid_list = &info->compatible_id_list;
1576                         for (i = 0; i < cid_list->count; i++)
1577                                 acpi_add_id(pnp, cid_list->ids[i].string);
1578                 }
1579                 if (info->valid & ACPI_VALID_ADR) {
1580                         pnp->bus_address = info->address;
1581                         pnp->type.bus_address = 1;
1582                 }
1583                 if (info->valid & ACPI_VALID_UID)
1584                         pnp->unique_id = kstrdup(info->unique_id.string,
1585                                                         GFP_KERNEL);
1586
1587                 kfree(info);
1588
1589                 /*
1590                  * Some devices don't reliably have _HIDs & _CIDs, so add
1591                  * synthetic HIDs to make sure drivers can find them.
1592                  */
1593                 if (acpi_is_video_device(handle))
1594                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1595                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1596                         acpi_add_id(pnp, ACPI_BAY_HID);
1597                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1598                         acpi_add_id(pnp, ACPI_DOCK_HID);
1599                 else if (!acpi_ibm_smbus_match(handle))
1600                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1601                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1602                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1603                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1604                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1605                 }
1606
1607                 break;
1608         case ACPI_BUS_TYPE_POWER:
1609                 acpi_add_id(pnp, ACPI_POWER_HID);
1610                 break;
1611         case ACPI_BUS_TYPE_PROCESSOR:
1612                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1613                 break;
1614         case ACPI_BUS_TYPE_THERMAL:
1615                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1616                 break;
1617         case ACPI_BUS_TYPE_POWER_BUTTON:
1618                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1619                 break;
1620         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1621                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1622                 break;
1623         }
1624 }
1625
1626 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1627 {
1628         struct acpi_hardware_id *id, *tmp;
1629
1630         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1631                 kfree(id->id);
1632                 kfree(id);
1633         }
1634         kfree(pnp->unique_id);
1635 }
1636
1637 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1638                              int type, unsigned long long sta)
1639 {
1640         INIT_LIST_HEAD(&device->pnp.ids);
1641         device->device_type = type;
1642         device->handle = handle;
1643         device->parent = acpi_bus_get_parent(handle);
1644         STRUCT_TO_INT(device->status) = sta;
1645         acpi_device_get_busid(device);
1646         acpi_set_pnp_ids(handle, &device->pnp, type);
1647         acpi_bus_get_flags(device);
1648         device->flags.match_driver = false;
1649         device_initialize(&device->dev);
1650         dev_set_uevent_suppress(&device->dev, true);
1651 }
1652
1653 void acpi_device_add_finalize(struct acpi_device *device)
1654 {
1655         device->flags.match_driver = true;
1656         dev_set_uevent_suppress(&device->dev, false);
1657         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1658 }
1659
1660 static int acpi_add_single_object(struct acpi_device **child,
1661                                   acpi_handle handle, int type,
1662                                   unsigned long long sta)
1663 {
1664         int result;
1665         struct acpi_device *device;
1666         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1667
1668         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1669         if (!device) {
1670                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1671                 return -ENOMEM;
1672         }
1673
1674         acpi_init_device_object(device, handle, type, sta);
1675         acpi_bus_get_power_flags(device);
1676         acpi_bus_get_wakeup_device_flags(device);
1677
1678         result = acpi_device_add(device, acpi_device_release);
1679         if (result) {
1680                 acpi_device_release(&device->dev);
1681                 return result;
1682         }
1683
1684         acpi_power_add_remove_device(device, true);
1685         acpi_device_add_finalize(device);
1686         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1687         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1688                 dev_name(&device->dev), (char *) buffer.pointer,
1689                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1690         kfree(buffer.pointer);
1691         *child = device;
1692         return 0;
1693 }
1694
1695 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1696                                     unsigned long long *sta)
1697 {
1698         acpi_status status;
1699         acpi_object_type acpi_type;
1700
1701         status = acpi_get_type(handle, &acpi_type);
1702         if (ACPI_FAILURE(status))
1703                 return -ENODEV;
1704
1705         switch (acpi_type) {
1706         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1707         case ACPI_TYPE_DEVICE:
1708                 *type = ACPI_BUS_TYPE_DEVICE;
1709                 status = acpi_bus_get_status_handle(handle, sta);
1710                 if (ACPI_FAILURE(status))
1711                         return -ENODEV;
1712                 break;
1713         case ACPI_TYPE_PROCESSOR:
1714                 *type = ACPI_BUS_TYPE_PROCESSOR;
1715                 status = acpi_bus_get_status_handle(handle, sta);
1716                 if (ACPI_FAILURE(status))
1717                         return -ENODEV;
1718                 break;
1719         case ACPI_TYPE_THERMAL:
1720                 *type = ACPI_BUS_TYPE_THERMAL;
1721                 *sta = ACPI_STA_DEFAULT;
1722                 break;
1723         case ACPI_TYPE_POWER:
1724                 *type = ACPI_BUS_TYPE_POWER;
1725                 *sta = ACPI_STA_DEFAULT;
1726                 break;
1727         default:
1728                 return -ENODEV;
1729         }
1730
1731         return 0;
1732 }
1733
1734 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1735                                        char *idstr,
1736                                        const struct acpi_device_id **matchid)
1737 {
1738         const struct acpi_device_id *devid;
1739
1740         for (devid = handler->ids; devid->id[0]; devid++)
1741                 if (!strcmp((char *)devid->id, idstr)) {
1742                         if (matchid)
1743                                 *matchid = devid;
1744
1745                         return true;
1746                 }
1747
1748         return false;
1749 }
1750
1751 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1752                                         const struct acpi_device_id **matchid)
1753 {
1754         struct acpi_scan_handler *handler;
1755
1756         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1757                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1758                         return handler;
1759
1760         return NULL;
1761 }
1762
1763 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1764 {
1765         if (!!hotplug->enabled == !!val)
1766                 return;
1767
1768         mutex_lock(&acpi_scan_lock);
1769
1770         hotplug->enabled = val;
1771
1772         mutex_unlock(&acpi_scan_lock);
1773 }
1774
1775 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1776 {
1777         struct acpi_device_pnp pnp = {};
1778         struct acpi_hardware_id *hwid;
1779         struct acpi_scan_handler *handler;
1780
1781         INIT_LIST_HEAD(&pnp.ids);
1782         acpi_set_pnp_ids(handle, &pnp, type);
1783
1784         if (!pnp.type.hardware_id)
1785                 goto out;
1786
1787         /*
1788          * This relies on the fact that acpi_install_notify_handler() will not
1789          * install the same notify handler routine twice for the same handle.
1790          */
1791         list_for_each_entry(hwid, &pnp.ids, list) {
1792                 handler = acpi_scan_match_handler(hwid->id, NULL);
1793                 if (handler) {
1794                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1795                                         acpi_hotplug_notify_cb, handler);
1796                         break;
1797                 }
1798         }
1799
1800 out:
1801         acpi_free_pnp_ids(&pnp);
1802 }
1803
1804 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1805                                       void *not_used, void **return_value)
1806 {
1807         struct acpi_device *device = NULL;
1808         int type;
1809         unsigned long long sta;
1810         acpi_status status;
1811         int result;
1812
1813         acpi_bus_get_device(handle, &device);
1814         if (device)
1815                 goto out;
1816
1817         result = acpi_bus_type_and_status(handle, &type, &sta);
1818         if (result)
1819                 return AE_OK;
1820
1821         if (type == ACPI_BUS_TYPE_POWER) {
1822                 acpi_add_power_resource(handle);
1823                 return AE_OK;
1824         }
1825
1826         acpi_scan_init_hotplug(handle, type);
1827
1828         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1829             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1830                 struct acpi_device_wakeup wakeup;
1831                 acpi_handle temp;
1832
1833                 status = acpi_get_handle(handle, "_PRW", &temp);
1834                 if (ACPI_SUCCESS(status)) {
1835                         acpi_bus_extract_wakeup_device_power_package(handle,
1836                                                                      &wakeup);
1837                         acpi_power_resources_list_free(&wakeup.resources);
1838                 }
1839                 return AE_CTRL_DEPTH;
1840         }
1841
1842         acpi_add_single_object(&device, handle, type, sta);
1843         if (!device)
1844                 return AE_CTRL_DEPTH;
1845
1846  out:
1847         if (!*return_value)
1848                 *return_value = device;
1849
1850         return AE_OK;
1851 }
1852
1853 static int acpi_scan_attach_handler(struct acpi_device *device)
1854 {
1855         struct acpi_hardware_id *hwid;
1856         int ret = 0;
1857
1858         list_for_each_entry(hwid, &device->pnp.ids, list) {
1859                 const struct acpi_device_id *devid;
1860                 struct acpi_scan_handler *handler;
1861
1862                 handler = acpi_scan_match_handler(hwid->id, &devid);
1863                 if (handler) {
1864                         ret = handler->attach(device, devid);
1865                         if (ret > 0) {
1866                                 device->handler = handler;
1867                                 break;
1868                         } else if (ret < 0) {
1869                                 break;
1870                         }
1871                 }
1872         }
1873         return ret;
1874 }
1875
1876 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1877                                           void *not_used, void **ret_not_used)
1878 {
1879         struct acpi_device *device;
1880         unsigned long long sta_not_used;
1881         int ret;
1882
1883         /*
1884          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1885          * namespace walks prematurely.
1886          */
1887         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1888                 return AE_OK;
1889
1890         if (acpi_bus_get_device(handle, &device))
1891                 return AE_CTRL_DEPTH;
1892
1893         ret = acpi_scan_attach_handler(device);
1894         if (ret)
1895                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1896
1897         ret = device_attach(&device->dev);
1898         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1899 }
1900
1901 /**
1902  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1903  * @handle: Root of the namespace scope to scan.
1904  *
1905  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1906  * found devices.
1907  *
1908  * If no devices were found, -ENODEV is returned, but it does not mean that
1909  * there has been a real error.  There just have been no suitable ACPI objects
1910  * in the table trunk from which the kernel could create a device and add an
1911  * appropriate driver.
1912  *
1913  * Must be called under acpi_scan_lock.
1914  */
1915 int acpi_bus_scan(acpi_handle handle)
1916 {
1917         void *device = NULL;
1918         int error = 0;
1919
1920         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1921                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1922                                     acpi_bus_check_add, NULL, NULL, &device);
1923
1924         if (!device)
1925                 error = -ENODEV;
1926         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1927                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1928                                     acpi_bus_device_attach, NULL, NULL, NULL);
1929
1930         return error;
1931 }
1932 EXPORT_SYMBOL(acpi_bus_scan);
1933
1934 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1935                                           void *not_used, void **ret_not_used)
1936 {
1937         struct acpi_device *device = NULL;
1938
1939         if (!acpi_bus_get_device(handle, &device)) {
1940                 struct acpi_scan_handler *dev_handler = device->handler;
1941
1942                 device->removal_type = ACPI_BUS_REMOVAL_EJECT;
1943                 if (dev_handler) {
1944                         if (dev_handler->detach)
1945                                 dev_handler->detach(device);
1946
1947                         device->handler = NULL;
1948                 } else {
1949                         device_release_driver(&device->dev);
1950                 }
1951         }
1952         return AE_OK;
1953 }
1954
1955 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1956                                    void *not_used, void **ret_not_used)
1957 {
1958         struct acpi_device *device = NULL;
1959
1960         if (!acpi_bus_get_device(handle, &device))
1961                 acpi_device_unregister(device);
1962
1963         return AE_OK;
1964 }
1965
1966 /**
1967  * acpi_bus_trim - Remove ACPI device node and all of its descendants
1968  * @start: Root of the ACPI device nodes subtree to remove.
1969  *
1970  * Must be called under acpi_scan_lock.
1971  */
1972 void acpi_bus_trim(struct acpi_device *start)
1973 {
1974         /*
1975          * Execute acpi_bus_device_detach() as a post-order callback to detach
1976          * all ACPI drivers from the device nodes being removed.
1977          */
1978         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1979                             acpi_bus_device_detach, NULL, NULL);
1980         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
1981         /*
1982          * Execute acpi_bus_remove() as a post-order callback to remove device
1983          * nodes in the given namespace scope.
1984          */
1985         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1986                             acpi_bus_remove, NULL, NULL);
1987         acpi_bus_remove(start->handle, 0, NULL, NULL);
1988 }
1989 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1990
1991 static int acpi_bus_scan_fixed(void)
1992 {
1993         int result = 0;
1994
1995         /*
1996          * Enumerate all fixed-feature devices.
1997          */
1998         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1999                 struct acpi_device *device = NULL;
2000
2001                 result = acpi_add_single_object(&device, NULL,
2002                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2003                                                 ACPI_STA_DEFAULT);
2004                 if (result)
2005                         return result;
2006
2007                 result = device_attach(&device->dev);
2008                 if (result < 0)
2009                         return result;
2010
2011                 device_init_wakeup(&device->dev, true);
2012         }
2013
2014         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2015                 struct acpi_device *device = NULL;
2016
2017                 result = acpi_add_single_object(&device, NULL,
2018                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2019                                                 ACPI_STA_DEFAULT);
2020                 if (result)
2021                         return result;
2022
2023                 result = device_attach(&device->dev);
2024         }
2025
2026         return result < 0 ? result : 0;
2027 }
2028
2029 int __init acpi_scan_init(void)
2030 {
2031         int result;
2032
2033         result = bus_register(&acpi_bus_type);
2034         if (result) {
2035                 /* We don't want to quit even if we failed to add suspend/resume */
2036                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2037         }
2038
2039         acpi_pci_root_init();
2040         acpi_pci_link_init();
2041         acpi_platform_init();
2042         acpi_lpss_init();
2043         acpi_container_init();
2044         acpi_memory_hotplug_init();
2045
2046         mutex_lock(&acpi_scan_lock);
2047         /*
2048          * Enumerate devices in the ACPI namespace.
2049          */
2050         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2051         if (result)
2052                 goto out;
2053
2054         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2055         if (result)
2056                 goto out;
2057
2058         result = acpi_bus_scan_fixed();
2059         if (result) {
2060                 acpi_device_unregister(acpi_root);
2061                 goto out;
2062         }
2063
2064         acpi_update_all_gpes();
2065
2066         acpi_pci_root_hp_init();
2067
2068  out:
2069         mutex_unlock(&acpi_scan_lock);
2070         return result;
2071 }