Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[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/acpi_iort.h>
11 #include <linux/signal.h>
12 #include <linux/kthread.h>
13 #include <linux/dmi.h>
14 #include <linux/nls.h>
15 #include <linux/dma-mapping.h>
16
17 #include <asm/pgtable.h>
18
19 #include "internal.h"
20
21 #define _COMPONENT              ACPI_BUS_COMPONENT
22 ACPI_MODULE_NAME("scan");
23 extern struct acpi_device *acpi_root;
24
25 #define ACPI_BUS_CLASS                  "system_bus"
26 #define ACPI_BUS_HID                    "LNXSYBUS"
27 #define ACPI_BUS_DEVICE_NAME            "System Bus"
28
29 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
30
31 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
32
33 static const char *dummy_hid = "device";
34
35 static LIST_HEAD(acpi_dep_list);
36 static DEFINE_MUTEX(acpi_dep_list_lock);
37 LIST_HEAD(acpi_bus_id_list);
38 static DEFINE_MUTEX(acpi_scan_lock);
39 static LIST_HEAD(acpi_scan_handlers_list);
40 DEFINE_MUTEX(acpi_device_lock);
41 LIST_HEAD(acpi_wakeup_device_list);
42 static DEFINE_MUTEX(acpi_hp_context_lock);
43
44 /*
45  * The UART device described by the SPCR table is the only object which needs
46  * special-casing. Everything else is covered by ACPI namespace paths in STAO
47  * table.
48  */
49 static u64 spcr_uart_addr;
50
51 struct acpi_dep_data {
52         struct list_head node;
53         acpi_handle master;
54         acpi_handle slave;
55 };
56
57 void acpi_scan_lock_acquire(void)
58 {
59         mutex_lock(&acpi_scan_lock);
60 }
61 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
62
63 void acpi_scan_lock_release(void)
64 {
65         mutex_unlock(&acpi_scan_lock);
66 }
67 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
68
69 void acpi_lock_hp_context(void)
70 {
71         mutex_lock(&acpi_hp_context_lock);
72 }
73
74 void acpi_unlock_hp_context(void)
75 {
76         mutex_unlock(&acpi_hp_context_lock);
77 }
78
79 void acpi_initialize_hp_context(struct acpi_device *adev,
80                                 struct acpi_hotplug_context *hp,
81                                 int (*notify)(struct acpi_device *, u32),
82                                 void (*uevent)(struct acpi_device *, u32))
83 {
84         acpi_lock_hp_context();
85         hp->notify = notify;
86         hp->uevent = uevent;
87         acpi_set_hp_context(adev, hp);
88         acpi_unlock_hp_context();
89 }
90 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
91
92 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
93 {
94         if (!handler)
95                 return -EINVAL;
96
97         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
98         return 0;
99 }
100
101 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
102                                        const char *hotplug_profile_name)
103 {
104         int error;
105
106         error = acpi_scan_add_handler(handler);
107         if (error)
108                 return error;
109
110         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
111         return 0;
112 }
113
114 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
115 {
116         struct acpi_device_physical_node *pn;
117         bool offline = true;
118
119         /*
120          * acpi_container_offline() calls this for all of the container's
121          * children under the container's physical_node_lock lock.
122          */
123         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
124
125         list_for_each_entry(pn, &adev->physical_node_list, node)
126                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
127                         if (uevent)
128                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
129
130                         offline = false;
131                         break;
132                 }
133
134         mutex_unlock(&adev->physical_node_lock);
135         return offline;
136 }
137
138 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
139                                     void **ret_p)
140 {
141         struct acpi_device *device = NULL;
142         struct acpi_device_physical_node *pn;
143         bool second_pass = (bool)data;
144         acpi_status status = AE_OK;
145
146         if (acpi_bus_get_device(handle, &device))
147                 return AE_OK;
148
149         if (device->handler && !device->handler->hotplug.enabled) {
150                 *ret_p = &device->dev;
151                 return AE_SUPPORT;
152         }
153
154         mutex_lock(&device->physical_node_lock);
155
156         list_for_each_entry(pn, &device->physical_node_list, node) {
157                 int ret;
158
159                 if (second_pass) {
160                         /* Skip devices offlined by the first pass. */
161                         if (pn->put_online)
162                                 continue;
163                 } else {
164                         pn->put_online = false;
165                 }
166                 ret = device_offline(pn->dev);
167                 if (ret >= 0) {
168                         pn->put_online = !ret;
169                 } else {
170                         *ret_p = pn->dev;
171                         if (second_pass) {
172                                 status = AE_ERROR;
173                                 break;
174                         }
175                 }
176         }
177
178         mutex_unlock(&device->physical_node_lock);
179
180         return status;
181 }
182
183 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
184                                    void **ret_p)
185 {
186         struct acpi_device *device = NULL;
187         struct acpi_device_physical_node *pn;
188
189         if (acpi_bus_get_device(handle, &device))
190                 return AE_OK;
191
192         mutex_lock(&device->physical_node_lock);
193
194         list_for_each_entry(pn, &device->physical_node_list, node)
195                 if (pn->put_online) {
196                         device_online(pn->dev);
197                         pn->put_online = false;
198                 }
199
200         mutex_unlock(&device->physical_node_lock);
201
202         return AE_OK;
203 }
204
205 static int acpi_scan_try_to_offline(struct acpi_device *device)
206 {
207         acpi_handle handle = device->handle;
208         struct device *errdev = NULL;
209         acpi_status status;
210
211         /*
212          * Carry out two passes here and ignore errors in the first pass,
213          * because if the devices in question are memory blocks and
214          * CONFIG_MEMCG is set, one of the blocks may hold data structures
215          * that the other blocks depend on, but it is not known in advance which
216          * block holds them.
217          *
218          * If the first pass is successful, the second one isn't needed, though.
219          */
220         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
221                                      NULL, acpi_bus_offline, (void *)false,
222                                      (void **)&errdev);
223         if (status == AE_SUPPORT) {
224                 dev_warn(errdev, "Offline disabled.\n");
225                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
226                                     acpi_bus_online, NULL, NULL, NULL);
227                 return -EPERM;
228         }
229         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
230         if (errdev) {
231                 errdev = NULL;
232                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
233                                     NULL, acpi_bus_offline, (void *)true,
234                                     (void **)&errdev);
235                 if (!errdev)
236                         acpi_bus_offline(handle, 0, (void *)true,
237                                          (void **)&errdev);
238
239                 if (errdev) {
240                         dev_warn(errdev, "Offline failed.\n");
241                         acpi_bus_online(handle, 0, NULL, NULL);
242                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
243                                             ACPI_UINT32_MAX, acpi_bus_online,
244                                             NULL, NULL, NULL);
245                         return -EBUSY;
246                 }
247         }
248         return 0;
249 }
250
251 static int acpi_scan_hot_remove(struct acpi_device *device)
252 {
253         acpi_handle handle = device->handle;
254         unsigned long long sta;
255         acpi_status status;
256
257         if (device->handler && device->handler->hotplug.demand_offline) {
258                 if (!acpi_scan_is_offline(device, true))
259                         return -EBUSY;
260         } else {
261                 int error = acpi_scan_try_to_offline(device);
262                 if (error)
263                         return error;
264         }
265
266         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
267                 "Hot-removing device %s...\n", dev_name(&device->dev)));
268
269         acpi_bus_trim(device);
270
271         acpi_evaluate_lck(handle, 0);
272         /*
273          * TBD: _EJD support.
274          */
275         status = acpi_evaluate_ej0(handle);
276         if (status == AE_NOT_FOUND)
277                 return -ENODEV;
278         else if (ACPI_FAILURE(status))
279                 return -EIO;
280
281         /*
282          * Verify if eject was indeed successful.  If not, log an error
283          * message.  No need to call _OST since _EJ0 call was made OK.
284          */
285         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
286         if (ACPI_FAILURE(status)) {
287                 acpi_handle_warn(handle,
288                         "Status check after eject failed (0x%x)\n", status);
289         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
290                 acpi_handle_warn(handle,
291                         "Eject incomplete - status 0x%llx\n", sta);
292         }
293
294         return 0;
295 }
296
297 static int acpi_scan_device_not_present(struct acpi_device *adev)
298 {
299         if (!acpi_device_enumerated(adev)) {
300                 dev_warn(&adev->dev, "Still not present\n");
301                 return -EALREADY;
302         }
303         acpi_bus_trim(adev);
304         return 0;
305 }
306
307 static int acpi_scan_device_check(struct acpi_device *adev)
308 {
309         int error;
310
311         acpi_bus_get_status(adev);
312         if (adev->status.present || adev->status.functional) {
313                 /*
314                  * This function is only called for device objects for which
315                  * matching scan handlers exist.  The only situation in which
316                  * the scan handler is not attached to this device object yet
317                  * is when the device has just appeared (either it wasn't
318                  * present at all before or it was removed and then added
319                  * again).
320                  */
321                 if (adev->handler) {
322                         dev_warn(&adev->dev, "Already enumerated\n");
323                         return -EALREADY;
324                 }
325                 error = acpi_bus_scan(adev->handle);
326                 if (error) {
327                         dev_warn(&adev->dev, "Namespace scan failure\n");
328                         return error;
329                 }
330                 if (!adev->handler) {
331                         dev_warn(&adev->dev, "Enumeration failure\n");
332                         error = -ENODEV;
333                 }
334         } else {
335                 error = acpi_scan_device_not_present(adev);
336         }
337         return error;
338 }
339
340 static int acpi_scan_bus_check(struct acpi_device *adev)
341 {
342         struct acpi_scan_handler *handler = adev->handler;
343         struct acpi_device *child;
344         int error;
345
346         acpi_bus_get_status(adev);
347         if (!(adev->status.present || adev->status.functional)) {
348                 acpi_scan_device_not_present(adev);
349                 return 0;
350         }
351         if (handler && handler->hotplug.scan_dependent)
352                 return handler->hotplug.scan_dependent(adev);
353
354         error = acpi_bus_scan(adev->handle);
355         if (error) {
356                 dev_warn(&adev->dev, "Namespace scan failure\n");
357                 return error;
358         }
359         list_for_each_entry(child, &adev->children, node) {
360                 error = acpi_scan_bus_check(child);
361                 if (error)
362                         return error;
363         }
364         return 0;
365 }
366
367 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
368 {
369         switch (type) {
370         case ACPI_NOTIFY_BUS_CHECK:
371                 return acpi_scan_bus_check(adev);
372         case ACPI_NOTIFY_DEVICE_CHECK:
373                 return acpi_scan_device_check(adev);
374         case ACPI_NOTIFY_EJECT_REQUEST:
375         case ACPI_OST_EC_OSPM_EJECT:
376                 if (adev->handler && !adev->handler->hotplug.enabled) {
377                         dev_info(&adev->dev, "Eject disabled\n");
378                         return -EPERM;
379                 }
380                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
381                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
382                 return acpi_scan_hot_remove(adev);
383         }
384         return -EINVAL;
385 }
386
387 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
388 {
389         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
390         int error = -ENODEV;
391
392         lock_device_hotplug();
393         mutex_lock(&acpi_scan_lock);
394
395         /*
396          * The device object's ACPI handle cannot become invalid as long as we
397          * are holding acpi_scan_lock, but it might have become invalid before
398          * that lock was acquired.
399          */
400         if (adev->handle == INVALID_ACPI_HANDLE)
401                 goto err_out;
402
403         if (adev->flags.is_dock_station) {
404                 error = dock_notify(adev, src);
405         } else if (adev->flags.hotplug_notify) {
406                 error = acpi_generic_hotplug_event(adev, src);
407         } else {
408                 int (*notify)(struct acpi_device *, u32);
409
410                 acpi_lock_hp_context();
411                 notify = adev->hp ? adev->hp->notify : NULL;
412                 acpi_unlock_hp_context();
413                 /*
414                  * There may be additional notify handlers for device objects
415                  * without the .event() callback, so ignore them here.
416                  */
417                 if (notify)
418                         error = notify(adev, src);
419                 else
420                         goto out;
421         }
422         switch (error) {
423         case 0:
424                 ost_code = ACPI_OST_SC_SUCCESS;
425                 break;
426         case -EPERM:
427                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
428                 break;
429         case -EBUSY:
430                 ost_code = ACPI_OST_SC_DEVICE_BUSY;
431                 break;
432         default:
433                 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
434                 break;
435         }
436
437  err_out:
438         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
439
440  out:
441         acpi_bus_put_acpi_device(adev);
442         mutex_unlock(&acpi_scan_lock);
443         unlock_device_hotplug();
444 }
445
446 static void acpi_free_power_resources_lists(struct acpi_device *device)
447 {
448         int i;
449
450         if (device->wakeup.flags.valid)
451                 acpi_power_resources_list_free(&device->wakeup.resources);
452
453         if (!device->power.flags.power_resources)
454                 return;
455
456         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
457                 struct acpi_device_power_state *ps = &device->power.states[i];
458                 acpi_power_resources_list_free(&ps->resources);
459         }
460 }
461
462 static void acpi_device_release(struct device *dev)
463 {
464         struct acpi_device *acpi_dev = to_acpi_device(dev);
465
466         acpi_free_properties(acpi_dev);
467         acpi_free_pnp_ids(&acpi_dev->pnp);
468         acpi_free_power_resources_lists(acpi_dev);
469         kfree(acpi_dev);
470 }
471
472 static void acpi_device_del(struct acpi_device *device)
473 {
474         struct acpi_device_bus_id *acpi_device_bus_id;
475
476         mutex_lock(&acpi_device_lock);
477         if (device->parent)
478                 list_del(&device->node);
479
480         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
481                 if (!strcmp(acpi_device_bus_id->bus_id,
482                             acpi_device_hid(device))) {
483                         if (acpi_device_bus_id->instance_no > 0)
484                                 acpi_device_bus_id->instance_no--;
485                         else {
486                                 list_del(&acpi_device_bus_id->node);
487                                 kfree(acpi_device_bus_id);
488                         }
489                         break;
490                 }
491
492         list_del(&device->wakeup_list);
493         mutex_unlock(&acpi_device_lock);
494
495         acpi_power_add_remove_device(device, false);
496         acpi_device_remove_files(device);
497         if (device->remove)
498                 device->remove(device);
499
500         device_del(&device->dev);
501 }
502
503 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
504
505 static LIST_HEAD(acpi_device_del_list);
506 static DEFINE_MUTEX(acpi_device_del_lock);
507
508 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
509 {
510         for (;;) {
511                 struct acpi_device *adev;
512
513                 mutex_lock(&acpi_device_del_lock);
514
515                 if (list_empty(&acpi_device_del_list)) {
516                         mutex_unlock(&acpi_device_del_lock);
517                         break;
518                 }
519                 adev = list_first_entry(&acpi_device_del_list,
520                                         struct acpi_device, del_list);
521                 list_del(&adev->del_list);
522
523                 mutex_unlock(&acpi_device_del_lock);
524
525                 blocking_notifier_call_chain(&acpi_reconfig_chain,
526                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
527
528                 acpi_device_del(adev);
529                 /*
530                  * Drop references to all power resources that might have been
531                  * used by the device.
532                  */
533                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
534                 put_device(&adev->dev);
535         }
536 }
537
538 /**
539  * acpi_scan_drop_device - Drop an ACPI device object.
540  * @handle: Handle of an ACPI namespace node, not used.
541  * @context: Address of the ACPI device object to drop.
542  *
543  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
544  * namespace node the device object pointed to by @context is attached to.
545  *
546  * The unregistration is carried out asynchronously to avoid running
547  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
548  * ensure the correct ordering (the device objects must be unregistered in the
549  * same order in which the corresponding namespace nodes are deleted).
550  */
551 static void acpi_scan_drop_device(acpi_handle handle, void *context)
552 {
553         static DECLARE_WORK(work, acpi_device_del_work_fn);
554         struct acpi_device *adev = context;
555
556         mutex_lock(&acpi_device_del_lock);
557
558         /*
559          * Use the ACPI hotplug workqueue which is ordered, so this work item
560          * won't run after any hotplug work items submitted subsequently.  That
561          * prevents attempts to register device objects identical to those being
562          * deleted from happening concurrently (such attempts result from
563          * hotplug events handled via the ACPI hotplug workqueue).  It also will
564          * run after all of the work items submitted previosuly, which helps
565          * those work items to ensure that they are not accessing stale device
566          * objects.
567          */
568         if (list_empty(&acpi_device_del_list))
569                 acpi_queue_hotplug_work(&work);
570
571         list_add_tail(&adev->del_list, &acpi_device_del_list);
572         /* Make acpi_ns_validate_handle() return NULL for this handle. */
573         adev->handle = INVALID_ACPI_HANDLE;
574
575         mutex_unlock(&acpi_device_del_lock);
576 }
577
578 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
579                                 void (*callback)(void *))
580 {
581         acpi_status status;
582
583         if (!device)
584                 return -EINVAL;
585
586         status = acpi_get_data_full(handle, acpi_scan_drop_device,
587                                     (void **)device, callback);
588         if (ACPI_FAILURE(status) || !*device) {
589                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
590                                   handle));
591                 return -ENODEV;
592         }
593         return 0;
594 }
595
596 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
597 {
598         return acpi_get_device_data(handle, device, NULL);
599 }
600 EXPORT_SYMBOL(acpi_bus_get_device);
601
602 static void get_acpi_device(void *dev)
603 {
604         if (dev)
605                 get_device(&((struct acpi_device *)dev)->dev);
606 }
607
608 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
609 {
610         struct acpi_device *adev = NULL;
611
612         acpi_get_device_data(handle, &adev, get_acpi_device);
613         return adev;
614 }
615
616 void acpi_bus_put_acpi_device(struct acpi_device *adev)
617 {
618         put_device(&adev->dev);
619 }
620
621 int acpi_device_add(struct acpi_device *device,
622                     void (*release)(struct device *))
623 {
624         int result;
625         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
626         int found = 0;
627
628         if (device->handle) {
629                 acpi_status status;
630
631                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
632                                           device);
633                 if (ACPI_FAILURE(status)) {
634                         acpi_handle_err(device->handle,
635                                         "Unable to attach device data\n");
636                         return -ENODEV;
637                 }
638         }
639
640         /*
641          * Linkage
642          * -------
643          * Link this device to its parent and siblings.
644          */
645         INIT_LIST_HEAD(&device->children);
646         INIT_LIST_HEAD(&device->node);
647         INIT_LIST_HEAD(&device->wakeup_list);
648         INIT_LIST_HEAD(&device->physical_node_list);
649         INIT_LIST_HEAD(&device->del_list);
650         mutex_init(&device->physical_node_lock);
651
652         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
653         if (!new_bus_id) {
654                 pr_err(PREFIX "Memory allocation error\n");
655                 result = -ENOMEM;
656                 goto err_detach;
657         }
658
659         mutex_lock(&acpi_device_lock);
660         /*
661          * Find suitable bus_id and instance number in acpi_bus_id_list
662          * If failed, create one and link it into acpi_bus_id_list
663          */
664         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
665                 if (!strcmp(acpi_device_bus_id->bus_id,
666                             acpi_device_hid(device))) {
667                         acpi_device_bus_id->instance_no++;
668                         found = 1;
669                         kfree(new_bus_id);
670                         break;
671                 }
672         }
673         if (!found) {
674                 acpi_device_bus_id = new_bus_id;
675                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
676                 acpi_device_bus_id->instance_no = 0;
677                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
678         }
679         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
680
681         if (device->parent)
682                 list_add_tail(&device->node, &device->parent->children);
683
684         if (device->wakeup.flags.valid)
685                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
686         mutex_unlock(&acpi_device_lock);
687
688         if (device->parent)
689                 device->dev.parent = &device->parent->dev;
690         device->dev.bus = &acpi_bus_type;
691         device->dev.release = release;
692         result = device_add(&device->dev);
693         if (result) {
694                 dev_err(&device->dev, "Error registering device\n");
695                 goto err;
696         }
697
698         result = acpi_device_setup_files(device);
699         if (result)
700                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
701                        dev_name(&device->dev));
702
703         return 0;
704
705  err:
706         mutex_lock(&acpi_device_lock);
707         if (device->parent)
708                 list_del(&device->node);
709         list_del(&device->wakeup_list);
710         mutex_unlock(&acpi_device_lock);
711
712  err_detach:
713         acpi_detach_data(device->handle, acpi_scan_drop_device);
714         return result;
715 }
716
717 /* --------------------------------------------------------------------------
718                                  Device Enumeration
719    -------------------------------------------------------------------------- */
720 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
721 {
722         struct acpi_device *device = NULL;
723         acpi_status status;
724
725         /*
726          * Fixed hardware devices do not appear in the namespace and do not
727          * have handles, but we fabricate acpi_devices for them, so we have
728          * to deal with them specially.
729          */
730         if (!handle)
731                 return acpi_root;
732
733         do {
734                 status = acpi_get_parent(handle, &handle);
735                 if (ACPI_FAILURE(status))
736                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
737         } while (acpi_bus_get_device(handle, &device));
738         return device;
739 }
740
741 acpi_status
742 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
743 {
744         acpi_status status;
745         acpi_handle tmp;
746         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
747         union acpi_object *obj;
748
749         status = acpi_get_handle(handle, "_EJD", &tmp);
750         if (ACPI_FAILURE(status))
751                 return status;
752
753         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
754         if (ACPI_SUCCESS(status)) {
755                 obj = buffer.pointer;
756                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
757                                          ejd);
758                 kfree(buffer.pointer);
759         }
760         return status;
761 }
762 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
763
764 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
765                                         struct acpi_device_wakeup *wakeup)
766 {
767         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
768         union acpi_object *package = NULL;
769         union acpi_object *element = NULL;
770         acpi_status status;
771         int err = -ENODATA;
772
773         if (!wakeup)
774                 return -EINVAL;
775
776         INIT_LIST_HEAD(&wakeup->resources);
777
778         /* _PRW */
779         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
780         if (ACPI_FAILURE(status)) {
781                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
782                 return err;
783         }
784
785         package = (union acpi_object *)buffer.pointer;
786
787         if (!package || package->package.count < 2)
788                 goto out;
789
790         element = &(package->package.elements[0]);
791         if (!element)
792                 goto out;
793
794         if (element->type == ACPI_TYPE_PACKAGE) {
795                 if ((element->package.count < 2) ||
796                     (element->package.elements[0].type !=
797                      ACPI_TYPE_LOCAL_REFERENCE)
798                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
799                         goto out;
800
801                 wakeup->gpe_device =
802                     element->package.elements[0].reference.handle;
803                 wakeup->gpe_number =
804                     (u32) element->package.elements[1].integer.value;
805         } else if (element->type == ACPI_TYPE_INTEGER) {
806                 wakeup->gpe_device = NULL;
807                 wakeup->gpe_number = element->integer.value;
808         } else {
809                 goto out;
810         }
811
812         element = &(package->package.elements[1]);
813         if (element->type != ACPI_TYPE_INTEGER)
814                 goto out;
815
816         wakeup->sleep_state = element->integer.value;
817
818         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
819         if (err)
820                 goto out;
821
822         if (!list_empty(&wakeup->resources)) {
823                 int sleep_state;
824
825                 err = acpi_power_wakeup_list_init(&wakeup->resources,
826                                                   &sleep_state);
827                 if (err) {
828                         acpi_handle_warn(handle, "Retrieving current states "
829                                          "of wakeup power resources failed\n");
830                         acpi_power_resources_list_free(&wakeup->resources);
831                         goto out;
832                 }
833                 if (sleep_state < wakeup->sleep_state) {
834                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
835                                          "(S%d) by S%d from power resources\n",
836                                          (int)wakeup->sleep_state, sleep_state);
837                         wakeup->sleep_state = sleep_state;
838                 }
839         }
840
841  out:
842         kfree(buffer.pointer);
843         return err;
844 }
845
846 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
847 {
848         static const struct acpi_device_id button_device_ids[] = {
849                 {"PNP0C0C", 0},
850                 {"PNP0C0D", 0},
851                 {"PNP0C0E", 0},
852                 {"", 0},
853         };
854         struct acpi_device_wakeup *wakeup = &device->wakeup;
855         acpi_status status;
856
857         wakeup->flags.notifier_present = 0;
858
859         /* Power button, Lid switch always enable wakeup */
860         if (!acpi_match_device_ids(device, button_device_ids)) {
861                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
862                         /* Do not use Lid/sleep button for S5 wakeup */
863                         if (wakeup->sleep_state == ACPI_STATE_S5)
864                                 wakeup->sleep_state = ACPI_STATE_S4;
865                 }
866                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
867                 device_set_wakeup_capable(&device->dev, true);
868                 return true;
869         }
870
871         status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
872                                          wakeup->gpe_number);
873         return ACPI_SUCCESS(status);
874 }
875
876 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
877 {
878         int err;
879
880         /* Presence of _PRW indicates wake capable */
881         if (!acpi_has_method(device->handle, "_PRW"))
882                 return;
883
884         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
885                                                            &device->wakeup);
886         if (err) {
887                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
888                 return;
889         }
890
891         device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
892         device->wakeup.prepare_count = 0;
893         /*
894          * Call _PSW/_DSW object to disable its ability to wake the sleeping
895          * system for the ACPI device with the _PRW object.
896          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
897          * So it is necessary to call _DSW object first. Only when it is not
898          * present will the _PSW object used.
899          */
900         err = acpi_device_sleep_wake(device, 0, 0, 0);
901         if (err)
902                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
903                                 "error in _DSW or _PSW evaluation\n"));
904 }
905
906 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
907 {
908         struct acpi_device_power_state *ps = &device->power.states[state];
909         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
910         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
911         acpi_status status;
912
913         INIT_LIST_HEAD(&ps->resources);
914
915         /* Evaluate "_PRx" to get referenced power resources */
916         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
917         if (ACPI_SUCCESS(status)) {
918                 union acpi_object *package = buffer.pointer;
919
920                 if (buffer.length && package
921                     && package->type == ACPI_TYPE_PACKAGE
922                     && package->package.count) {
923                         int err = acpi_extract_power_resources(package, 0,
924                                                                &ps->resources);
925                         if (!err)
926                                 device->power.flags.power_resources = 1;
927                 }
928                 ACPI_FREE(buffer.pointer);
929         }
930
931         /* Evaluate "_PSx" to see if we can do explicit sets */
932         pathname[2] = 'S';
933         if (acpi_has_method(device->handle, pathname))
934                 ps->flags.explicit_set = 1;
935
936         /* State is valid if there are means to put the device into it. */
937         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
938                 ps->flags.valid = 1;
939
940         ps->power = -1;         /* Unknown - driver assigned */
941         ps->latency = -1;       /* Unknown - driver assigned */
942 }
943
944 static void acpi_bus_get_power_flags(struct acpi_device *device)
945 {
946         u32 i;
947
948         /* Presence of _PS0|_PR0 indicates 'power manageable' */
949         if (!acpi_has_method(device->handle, "_PS0") &&
950             !acpi_has_method(device->handle, "_PR0"))
951                 return;
952
953         device->flags.power_manageable = 1;
954
955         /*
956          * Power Management Flags
957          */
958         if (acpi_has_method(device->handle, "_PSC"))
959                 device->power.flags.explicit_get = 1;
960
961         if (acpi_has_method(device->handle, "_IRC"))
962                 device->power.flags.inrush_current = 1;
963
964         if (acpi_has_method(device->handle, "_DSW"))
965                 device->power.flags.dsw_present = 1;
966
967         /*
968          * Enumerate supported power management states
969          */
970         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
971                 acpi_bus_init_power_state(device, i);
972
973         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
974         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
975                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
976
977         /* Set defaults for D0 and D3hot states (always valid) */
978         device->power.states[ACPI_STATE_D0].flags.valid = 1;
979         device->power.states[ACPI_STATE_D0].power = 100;
980         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
981
982         if (acpi_bus_init_power(device))
983                 device->flags.power_manageable = 0;
984 }
985
986 static void acpi_bus_get_flags(struct acpi_device *device)
987 {
988         /* Presence of _STA indicates 'dynamic_status' */
989         if (acpi_has_method(device->handle, "_STA"))
990                 device->flags.dynamic_status = 1;
991
992         /* Presence of _RMV indicates 'removable' */
993         if (acpi_has_method(device->handle, "_RMV"))
994                 device->flags.removable = 1;
995
996         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
997         if (acpi_has_method(device->handle, "_EJD") ||
998             acpi_has_method(device->handle, "_EJ0"))
999                 device->flags.ejectable = 1;
1000 }
1001
1002 static void acpi_device_get_busid(struct acpi_device *device)
1003 {
1004         char bus_id[5] = { '?', 0 };
1005         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1006         int i = 0;
1007
1008         /*
1009          * Bus ID
1010          * ------
1011          * The device's Bus ID is simply the object name.
1012          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1013          */
1014         if (ACPI_IS_ROOT_DEVICE(device)) {
1015                 strcpy(device->pnp.bus_id, "ACPI");
1016                 return;
1017         }
1018
1019         switch (device->device_type) {
1020         case ACPI_BUS_TYPE_POWER_BUTTON:
1021                 strcpy(device->pnp.bus_id, "PWRF");
1022                 break;
1023         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1024                 strcpy(device->pnp.bus_id, "SLPF");
1025                 break;
1026         default:
1027                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1028                 /* Clean up trailing underscores (if any) */
1029                 for (i = 3; i > 1; i--) {
1030                         if (bus_id[i] == '_')
1031                                 bus_id[i] = '\0';
1032                         else
1033                                 break;
1034                 }
1035                 strcpy(device->pnp.bus_id, bus_id);
1036                 break;
1037         }
1038 }
1039
1040 /*
1041  * acpi_ata_match - see if an acpi object is an ATA device
1042  *
1043  * If an acpi object has one of the ACPI ATA methods defined,
1044  * then we can safely call it an ATA device.
1045  */
1046 bool acpi_ata_match(acpi_handle handle)
1047 {
1048         return acpi_has_method(handle, "_GTF") ||
1049                acpi_has_method(handle, "_GTM") ||
1050                acpi_has_method(handle, "_STM") ||
1051                acpi_has_method(handle, "_SDD");
1052 }
1053
1054 /*
1055  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1056  *
1057  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1058  * then we can safely call it an ejectable drive bay
1059  */
1060 bool acpi_bay_match(acpi_handle handle)
1061 {
1062         acpi_handle phandle;
1063
1064         if (!acpi_has_method(handle, "_EJ0"))
1065                 return false;
1066         if (acpi_ata_match(handle))
1067                 return true;
1068         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1069                 return false;
1070
1071         return acpi_ata_match(phandle);
1072 }
1073
1074 bool acpi_device_is_battery(struct acpi_device *adev)
1075 {
1076         struct acpi_hardware_id *hwid;
1077
1078         list_for_each_entry(hwid, &adev->pnp.ids, list)
1079                 if (!strcmp("PNP0C0A", hwid->id))
1080                         return true;
1081
1082         return false;
1083 }
1084
1085 static bool is_ejectable_bay(struct acpi_device *adev)
1086 {
1087         acpi_handle handle = adev->handle;
1088
1089         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1090                 return true;
1091
1092         return acpi_bay_match(handle);
1093 }
1094
1095 /*
1096  * acpi_dock_match - see if an acpi object has a _DCK method
1097  */
1098 bool acpi_dock_match(acpi_handle handle)
1099 {
1100         return acpi_has_method(handle, "_DCK");
1101 }
1102
1103 static acpi_status
1104 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1105                           void **return_value)
1106 {
1107         long *cap = context;
1108
1109         if (acpi_has_method(handle, "_BCM") &&
1110             acpi_has_method(handle, "_BCL")) {
1111                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1112                                   "support\n"));
1113                 *cap |= ACPI_VIDEO_BACKLIGHT;
1114                 /* We have backlight support, no need to scan further */
1115                 return AE_CTRL_TERMINATE;
1116         }
1117         return 0;
1118 }
1119
1120 /* Returns true if the ACPI object is a video device which can be
1121  * handled by video.ko.
1122  * The device will get a Linux specific CID added in scan.c to
1123  * identify the device as an ACPI graphics device
1124  * Be aware that the graphics device may not be physically present
1125  * Use acpi_video_get_capabilities() to detect general ACPI video
1126  * capabilities of present cards
1127  */
1128 long acpi_is_video_device(acpi_handle handle)
1129 {
1130         long video_caps = 0;
1131
1132         /* Is this device able to support video switching ? */
1133         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1134                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1135
1136         /* Is this device able to retrieve a video ROM ? */
1137         if (acpi_has_method(handle, "_ROM"))
1138                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1139
1140         /* Is this device able to configure which video head to be POSTed ? */
1141         if (acpi_has_method(handle, "_VPO") &&
1142             acpi_has_method(handle, "_GPD") &&
1143             acpi_has_method(handle, "_SPD"))
1144                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1145
1146         /* Only check for backlight functionality if one of the above hit. */
1147         if (video_caps)
1148                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1149                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1150                                     &video_caps, NULL);
1151
1152         return video_caps;
1153 }
1154 EXPORT_SYMBOL(acpi_is_video_device);
1155
1156 const char *acpi_device_hid(struct acpi_device *device)
1157 {
1158         struct acpi_hardware_id *hid;
1159
1160         if (list_empty(&device->pnp.ids))
1161                 return dummy_hid;
1162
1163         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1164         return hid->id;
1165 }
1166 EXPORT_SYMBOL(acpi_device_hid);
1167
1168 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1169 {
1170         struct acpi_hardware_id *id;
1171
1172         id = kmalloc(sizeof(*id), GFP_KERNEL);
1173         if (!id)
1174                 return;
1175
1176         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1177         if (!id->id) {
1178                 kfree(id);
1179                 return;
1180         }
1181
1182         list_add_tail(&id->list, &pnp->ids);
1183         pnp->type.hardware_id = 1;
1184 }
1185
1186 /*
1187  * Old IBM workstations have a DSDT bug wherein the SMBus object
1188  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1189  * prefix.  Work around this.
1190  */
1191 static bool acpi_ibm_smbus_match(acpi_handle handle)
1192 {
1193         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1194         struct acpi_buffer path = { sizeof(node_name), node_name };
1195
1196         if (!dmi_name_in_vendors("IBM"))
1197                 return false;
1198
1199         /* Look for SMBS object */
1200         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1201             strcmp("SMBS", path.pointer))
1202                 return false;
1203
1204         /* Does it have the necessary (but misnamed) methods? */
1205         if (acpi_has_method(handle, "SBI") &&
1206             acpi_has_method(handle, "SBR") &&
1207             acpi_has_method(handle, "SBW"))
1208                 return true;
1209
1210         return false;
1211 }
1212
1213 static bool acpi_object_is_system_bus(acpi_handle handle)
1214 {
1215         acpi_handle tmp;
1216
1217         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1218             tmp == handle)
1219                 return true;
1220         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1221             tmp == handle)
1222                 return true;
1223
1224         return false;
1225 }
1226
1227 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1228                                 int device_type)
1229 {
1230         acpi_status status;
1231         struct acpi_device_info *info;
1232         struct acpi_pnp_device_id_list *cid_list;
1233         int i;
1234
1235         switch (device_type) {
1236         case ACPI_BUS_TYPE_DEVICE:
1237                 if (handle == ACPI_ROOT_OBJECT) {
1238                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1239                         break;
1240                 }
1241
1242                 status = acpi_get_object_info(handle, &info);
1243                 if (ACPI_FAILURE(status)) {
1244                         pr_err(PREFIX "%s: Error reading device info\n",
1245                                         __func__);
1246                         return;
1247                 }
1248
1249                 if (info->valid & ACPI_VALID_HID) {
1250                         acpi_add_id(pnp, info->hardware_id.string);
1251                         pnp->type.platform_id = 1;
1252                 }
1253                 if (info->valid & ACPI_VALID_CID) {
1254                         cid_list = &info->compatible_id_list;
1255                         for (i = 0; i < cid_list->count; i++)
1256                                 acpi_add_id(pnp, cid_list->ids[i].string);
1257                 }
1258                 if (info->valid & ACPI_VALID_ADR) {
1259                         pnp->bus_address = info->address;
1260                         pnp->type.bus_address = 1;
1261                 }
1262                 if (info->valid & ACPI_VALID_UID)
1263                         pnp->unique_id = kstrdup(info->unique_id.string,
1264                                                         GFP_KERNEL);
1265                 if (info->valid & ACPI_VALID_CLS)
1266                         acpi_add_id(pnp, info->class_code.string);
1267
1268                 kfree(info);
1269
1270                 /*
1271                  * Some devices don't reliably have _HIDs & _CIDs, so add
1272                  * synthetic HIDs to make sure drivers can find them.
1273                  */
1274                 if (acpi_is_video_device(handle))
1275                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1276                 else if (acpi_bay_match(handle))
1277                         acpi_add_id(pnp, ACPI_BAY_HID);
1278                 else if (acpi_dock_match(handle))
1279                         acpi_add_id(pnp, ACPI_DOCK_HID);
1280                 else if (acpi_ibm_smbus_match(handle))
1281                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1282                 else if (list_empty(&pnp->ids) &&
1283                          acpi_object_is_system_bus(handle)) {
1284                         /* \_SB, \_TZ, LNXSYBUS */
1285                         acpi_add_id(pnp, ACPI_BUS_HID);
1286                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1287                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1288                 }
1289
1290                 break;
1291         case ACPI_BUS_TYPE_POWER:
1292                 acpi_add_id(pnp, ACPI_POWER_HID);
1293                 break;
1294         case ACPI_BUS_TYPE_PROCESSOR:
1295                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1296                 break;
1297         case ACPI_BUS_TYPE_THERMAL:
1298                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1299                 break;
1300         case ACPI_BUS_TYPE_POWER_BUTTON:
1301                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1302                 break;
1303         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1304                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1305                 break;
1306         }
1307 }
1308
1309 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1310 {
1311         struct acpi_hardware_id *id, *tmp;
1312
1313         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1314                 kfree_const(id->id);
1315                 kfree(id);
1316         }
1317         kfree(pnp->unique_id);
1318 }
1319
1320 /**
1321  * acpi_dma_supported - Check DMA support for the specified device.
1322  * @adev: The pointer to acpi device
1323  *
1324  * Return false if DMA is not supported. Otherwise, return true
1325  */
1326 bool acpi_dma_supported(struct acpi_device *adev)
1327 {
1328         if (!adev)
1329                 return false;
1330
1331         if (adev->flags.cca_seen)
1332                 return true;
1333
1334         /*
1335         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1336         * DMA on "Intel platforms".  Presumably that includes all x86 and
1337         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1338         */
1339         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1340                 return true;
1341
1342         return false;
1343 }
1344
1345 /**
1346  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1347  * @adev: The pointer to acpi device
1348  *
1349  * Return enum dev_dma_attr.
1350  */
1351 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1352 {
1353         if (!acpi_dma_supported(adev))
1354                 return DEV_DMA_NOT_SUPPORTED;
1355
1356         if (adev->flags.coherent_dma)
1357                 return DEV_DMA_COHERENT;
1358         else
1359                 return DEV_DMA_NON_COHERENT;
1360 }
1361
1362 /**
1363  * acpi_dma_configure - Set-up DMA configuration for the device.
1364  * @dev: The pointer to the device
1365  * @attr: device dma attributes
1366  */
1367 int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1368 {
1369         const struct iommu_ops *iommu;
1370         u64 size;
1371
1372         iort_set_dma_mask(dev);
1373
1374         iommu = iort_iommu_configure(dev);
1375         if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1376                 return -EPROBE_DEFER;
1377
1378         size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
1379         /*
1380          * Assume dma valid range starts at 0 and covers the whole
1381          * coherent_dma_mask.
1382          */
1383         arch_setup_dma_ops(dev, 0, size, iommu, attr == DEV_DMA_COHERENT);
1384
1385         return 0;
1386 }
1387 EXPORT_SYMBOL_GPL(acpi_dma_configure);
1388
1389 /**
1390  * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1391  * @dev: The pointer to the device
1392  */
1393 void acpi_dma_deconfigure(struct device *dev)
1394 {
1395         arch_teardown_dma_ops(dev);
1396 }
1397 EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1398
1399 static void acpi_init_coherency(struct acpi_device *adev)
1400 {
1401         unsigned long long cca = 0;
1402         acpi_status status;
1403         struct acpi_device *parent = adev->parent;
1404
1405         if (parent && parent->flags.cca_seen) {
1406                 /*
1407                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1408                  * already saw one.
1409                  */
1410                 adev->flags.cca_seen = 1;
1411                 cca = parent->flags.coherent_dma;
1412         } else {
1413                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1414                                                NULL, &cca);
1415                 if (ACPI_SUCCESS(status))
1416                         adev->flags.cca_seen = 1;
1417                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1418                         /*
1419                          * If architecture does not specify that _CCA is
1420                          * required for DMA-able devices (e.g. x86),
1421                          * we default to _CCA=1.
1422                          */
1423                         cca = 1;
1424                 else
1425                         acpi_handle_debug(adev->handle,
1426                                           "ACPI device is missing _CCA.\n");
1427         }
1428
1429         adev->flags.coherent_dma = cca;
1430 }
1431
1432 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
1433 {
1434         bool *is_spi_i2c_slave_p = data;
1435
1436         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1437                 return 1;
1438
1439         /*
1440          * devices that are connected to UART still need to be enumerated to
1441          * platform bus
1442          */
1443         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1444                 *is_spi_i2c_slave_p = true;
1445
1446          /* no need to do more checking */
1447         return -1;
1448 }
1449
1450 static bool acpi_is_spi_i2c_slave(struct acpi_device *device)
1451 {
1452         struct list_head resource_list;
1453         bool is_spi_i2c_slave = false;
1454
1455         INIT_LIST_HEAD(&resource_list);
1456         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1457                                &is_spi_i2c_slave);
1458         acpi_dev_free_resource_list(&resource_list);
1459
1460         return is_spi_i2c_slave;
1461 }
1462
1463 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1464                              int type, unsigned long long sta)
1465 {
1466         INIT_LIST_HEAD(&device->pnp.ids);
1467         device->device_type = type;
1468         device->handle = handle;
1469         device->parent = acpi_bus_get_parent(handle);
1470         device->fwnode.type = FWNODE_ACPI;
1471         device->fwnode.ops = &acpi_fwnode_ops;
1472         acpi_set_device_status(device, sta);
1473         acpi_device_get_busid(device);
1474         acpi_set_pnp_ids(handle, &device->pnp, type);
1475         acpi_init_properties(device);
1476         acpi_bus_get_flags(device);
1477         device->flags.match_driver = false;
1478         device->flags.initialized = true;
1479         device->flags.spi_i2c_slave = acpi_is_spi_i2c_slave(device);
1480         acpi_device_clear_enumerated(device);
1481         device_initialize(&device->dev);
1482         dev_set_uevent_suppress(&device->dev, true);
1483         acpi_init_coherency(device);
1484 }
1485
1486 void acpi_device_add_finalize(struct acpi_device *device)
1487 {
1488         dev_set_uevent_suppress(&device->dev, false);
1489         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1490 }
1491
1492 static int acpi_add_single_object(struct acpi_device **child,
1493                                   acpi_handle handle, int type,
1494                                   unsigned long long sta)
1495 {
1496         int result;
1497         struct acpi_device *device;
1498         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1499
1500         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1501         if (!device) {
1502                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1503                 return -ENOMEM;
1504         }
1505
1506         acpi_init_device_object(device, handle, type, sta);
1507         acpi_bus_get_power_flags(device);
1508         acpi_bus_get_wakeup_device_flags(device);
1509
1510         result = acpi_device_add(device, acpi_device_release);
1511         if (result) {
1512                 acpi_device_release(&device->dev);
1513                 return result;
1514         }
1515
1516         acpi_power_add_remove_device(device, true);
1517         acpi_device_add_finalize(device);
1518         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1519         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1520                 dev_name(&device->dev), (char *) buffer.pointer,
1521                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1522         kfree(buffer.pointer);
1523         *child = device;
1524         return 0;
1525 }
1526
1527 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1528                                             void *context)
1529 {
1530         struct resource *res = context;
1531
1532         if (acpi_dev_resource_memory(ares, res))
1533                 return AE_CTRL_TERMINATE;
1534
1535         return AE_OK;
1536 }
1537
1538 static bool acpi_device_should_be_hidden(acpi_handle handle)
1539 {
1540         acpi_status status;
1541         struct resource res;
1542
1543         /* Check if it should ignore the UART device */
1544         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1545                 return false;
1546
1547         /*
1548          * The UART device described in SPCR table is assumed to have only one
1549          * memory resource present. So we only look for the first one here.
1550          */
1551         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1552                                      acpi_get_resource_memory, &res);
1553         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1554                 return false;
1555
1556         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1557                          &res.start);
1558
1559         return true;
1560 }
1561
1562 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1563                                     unsigned long long *sta)
1564 {
1565         acpi_status status;
1566         acpi_object_type acpi_type;
1567
1568         status = acpi_get_type(handle, &acpi_type);
1569         if (ACPI_FAILURE(status))
1570                 return -ENODEV;
1571
1572         switch (acpi_type) {
1573         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1574         case ACPI_TYPE_DEVICE:
1575                 if (acpi_device_should_be_hidden(handle))
1576                         return -ENODEV;
1577
1578                 *type = ACPI_BUS_TYPE_DEVICE;
1579                 status = acpi_bus_get_status_handle(handle, sta);
1580                 if (ACPI_FAILURE(status))
1581                         *sta = 0;
1582                 break;
1583         case ACPI_TYPE_PROCESSOR:
1584                 *type = ACPI_BUS_TYPE_PROCESSOR;
1585                 status = acpi_bus_get_status_handle(handle, sta);
1586                 if (ACPI_FAILURE(status))
1587                         return -ENODEV;
1588                 break;
1589         case ACPI_TYPE_THERMAL:
1590                 *type = ACPI_BUS_TYPE_THERMAL;
1591                 *sta = ACPI_STA_DEFAULT;
1592                 break;
1593         case ACPI_TYPE_POWER:
1594                 *type = ACPI_BUS_TYPE_POWER;
1595                 *sta = ACPI_STA_DEFAULT;
1596                 break;
1597         default:
1598                 return -ENODEV;
1599         }
1600
1601         return 0;
1602 }
1603
1604 bool acpi_device_is_present(const struct acpi_device *adev)
1605 {
1606         return adev->status.present || adev->status.functional;
1607 }
1608
1609 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1610                                        const char *idstr,
1611                                        const struct acpi_device_id **matchid)
1612 {
1613         const struct acpi_device_id *devid;
1614
1615         if (handler->match)
1616                 return handler->match(idstr, matchid);
1617
1618         for (devid = handler->ids; devid->id[0]; devid++)
1619                 if (!strcmp((char *)devid->id, idstr)) {
1620                         if (matchid)
1621                                 *matchid = devid;
1622
1623                         return true;
1624                 }
1625
1626         return false;
1627 }
1628
1629 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1630                                         const struct acpi_device_id **matchid)
1631 {
1632         struct acpi_scan_handler *handler;
1633
1634         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1635                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1636                         return handler;
1637
1638         return NULL;
1639 }
1640
1641 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1642 {
1643         if (!!hotplug->enabled == !!val)
1644                 return;
1645
1646         mutex_lock(&acpi_scan_lock);
1647
1648         hotplug->enabled = val;
1649
1650         mutex_unlock(&acpi_scan_lock);
1651 }
1652
1653 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1654 {
1655         struct acpi_hardware_id *hwid;
1656
1657         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1658                 acpi_dock_add(adev);
1659                 return;
1660         }
1661         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1662                 struct acpi_scan_handler *handler;
1663
1664                 handler = acpi_scan_match_handler(hwid->id, NULL);
1665                 if (handler) {
1666                         adev->flags.hotplug_notify = true;
1667                         break;
1668                 }
1669         }
1670 }
1671
1672 static void acpi_device_dep_initialize(struct acpi_device *adev)
1673 {
1674         struct acpi_dep_data *dep;
1675         struct acpi_handle_list dep_devices;
1676         acpi_status status;
1677         int i;
1678
1679         if (!acpi_has_method(adev->handle, "_DEP"))
1680                 return;
1681
1682         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1683                                         &dep_devices);
1684         if (ACPI_FAILURE(status)) {
1685                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1686                 return;
1687         }
1688
1689         for (i = 0; i < dep_devices.count; i++) {
1690                 struct acpi_device_info *info;
1691                 int skip;
1692
1693                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1694                 if (ACPI_FAILURE(status)) {
1695                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1696                         continue;
1697                 }
1698
1699                 /*
1700                  * Skip the dependency of Windows System Power
1701                  * Management Controller
1702                  */
1703                 skip = info->valid & ACPI_VALID_HID &&
1704                         !strcmp(info->hardware_id.string, "INT3396");
1705
1706                 kfree(info);
1707
1708                 if (skip)
1709                         continue;
1710
1711                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1712                 if (!dep)
1713                         return;
1714
1715                 dep->master = dep_devices.handles[i];
1716                 dep->slave  = adev->handle;
1717                 adev->dep_unmet++;
1718
1719                 mutex_lock(&acpi_dep_list_lock);
1720                 list_add_tail(&dep->node , &acpi_dep_list);
1721                 mutex_unlock(&acpi_dep_list_lock);
1722         }
1723 }
1724
1725 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1726                                       void *not_used, void **return_value)
1727 {
1728         struct acpi_device *device = NULL;
1729         int type;
1730         unsigned long long sta;
1731         int result;
1732
1733         acpi_bus_get_device(handle, &device);
1734         if (device)
1735                 goto out;
1736
1737         result = acpi_bus_type_and_status(handle, &type, &sta);
1738         if (result)
1739                 return AE_OK;
1740
1741         if (type == ACPI_BUS_TYPE_POWER) {
1742                 acpi_add_power_resource(handle);
1743                 return AE_OK;
1744         }
1745
1746         acpi_add_single_object(&device, handle, type, sta);
1747         if (!device)
1748                 return AE_CTRL_DEPTH;
1749
1750         acpi_scan_init_hotplug(device);
1751         acpi_device_dep_initialize(device);
1752
1753  out:
1754         if (!*return_value)
1755                 *return_value = device;
1756
1757         return AE_OK;
1758 }
1759
1760 static void acpi_default_enumeration(struct acpi_device *device)
1761 {
1762         /*
1763          * Do not enumerate SPI/I2C slaves as they will be enumerated by their
1764          * respective parents.
1765          */
1766         if (!device->flags.spi_i2c_slave) {
1767                 acpi_create_platform_device(device, NULL);
1768                 acpi_device_set_enumerated(device);
1769         } else {
1770                 blocking_notifier_call_chain(&acpi_reconfig_chain,
1771                                              ACPI_RECONFIG_DEVICE_ADD, device);
1772         }
1773 }
1774
1775 static const struct acpi_device_id generic_device_ids[] = {
1776         {ACPI_DT_NAMESPACE_HID, },
1777         {"", },
1778 };
1779
1780 static int acpi_generic_device_attach(struct acpi_device *adev,
1781                                       const struct acpi_device_id *not_used)
1782 {
1783         /*
1784          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1785          * below can be unconditional.
1786          */
1787         if (adev->data.of_compatible)
1788                 acpi_default_enumeration(adev);
1789
1790         return 1;
1791 }
1792
1793 static struct acpi_scan_handler generic_device_handler = {
1794         .ids = generic_device_ids,
1795         .attach = acpi_generic_device_attach,
1796 };
1797
1798 static int acpi_scan_attach_handler(struct acpi_device *device)
1799 {
1800         struct acpi_hardware_id *hwid;
1801         int ret = 0;
1802
1803         list_for_each_entry(hwid, &device->pnp.ids, list) {
1804                 const struct acpi_device_id *devid;
1805                 struct acpi_scan_handler *handler;
1806
1807                 handler = acpi_scan_match_handler(hwid->id, &devid);
1808                 if (handler) {
1809                         if (!handler->attach) {
1810                                 device->pnp.type.platform_id = 0;
1811                                 continue;
1812                         }
1813                         device->handler = handler;
1814                         ret = handler->attach(device, devid);
1815                         if (ret > 0)
1816                                 break;
1817
1818                         device->handler = NULL;
1819                         if (ret < 0)
1820                                 break;
1821                 }
1822         }
1823
1824         return ret;
1825 }
1826
1827 static void acpi_bus_attach(struct acpi_device *device)
1828 {
1829         struct acpi_device *child;
1830         acpi_handle ejd;
1831         int ret;
1832
1833         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1834                 register_dock_dependent_device(device, ejd);
1835
1836         acpi_bus_get_status(device);
1837         /* Skip devices that are not present. */
1838         if (!acpi_device_is_present(device)) {
1839                 device->flags.initialized = false;
1840                 acpi_device_clear_enumerated(device);
1841                 device->flags.power_manageable = 0;
1842                 return;
1843         }
1844         if (device->handler)
1845                 goto ok;
1846
1847         if (!device->flags.initialized) {
1848                 device->flags.power_manageable =
1849                         device->power.states[ACPI_STATE_D0].flags.valid;
1850                 if (acpi_bus_init_power(device))
1851                         device->flags.power_manageable = 0;
1852
1853                 device->flags.initialized = true;
1854         } else if (device->flags.visited) {
1855                 goto ok;
1856         }
1857
1858         ret = acpi_scan_attach_handler(device);
1859         if (ret < 0)
1860                 return;
1861
1862         device->flags.match_driver = true;
1863         if (ret > 0 && !device->flags.spi_i2c_slave) {
1864                 acpi_device_set_enumerated(device);
1865                 goto ok;
1866         }
1867
1868         ret = device_attach(&device->dev);
1869         if (ret < 0)
1870                 return;
1871
1872         if (!device->pnp.type.platform_id && !device->flags.spi_i2c_slave)
1873                 acpi_device_set_enumerated(device);
1874         else
1875                 acpi_default_enumeration(device);
1876
1877  ok:
1878         list_for_each_entry(child, &device->children, node)
1879                 acpi_bus_attach(child);
1880
1881         if (device->handler && device->handler->hotplug.notify_online)
1882                 device->handler->hotplug.notify_online(device);
1883 }
1884
1885 void acpi_walk_dep_device_list(acpi_handle handle)
1886 {
1887         struct acpi_dep_data *dep, *tmp;
1888         struct acpi_device *adev;
1889
1890         mutex_lock(&acpi_dep_list_lock);
1891         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1892                 if (dep->master == handle) {
1893                         acpi_bus_get_device(dep->slave, &adev);
1894                         if (!adev)
1895                                 continue;
1896
1897                         adev->dep_unmet--;
1898                         if (!adev->dep_unmet)
1899                                 acpi_bus_attach(adev);
1900                         list_del(&dep->node);
1901                         kfree(dep);
1902                 }
1903         }
1904         mutex_unlock(&acpi_dep_list_lock);
1905 }
1906 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1907
1908 /**
1909  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1910  * @handle: Root of the namespace scope to scan.
1911  *
1912  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1913  * found devices.
1914  *
1915  * If no devices were found, -ENODEV is returned, but it does not mean that
1916  * there has been a real error.  There just have been no suitable ACPI objects
1917  * in the table trunk from which the kernel could create a device and add an
1918  * appropriate driver.
1919  *
1920  * Must be called under acpi_scan_lock.
1921  */
1922 int acpi_bus_scan(acpi_handle handle)
1923 {
1924         void *device = NULL;
1925
1926         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1927                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1928                                     acpi_bus_check_add, NULL, NULL, &device);
1929
1930         if (device) {
1931                 acpi_bus_attach(device);
1932                 return 0;
1933         }
1934         return -ENODEV;
1935 }
1936 EXPORT_SYMBOL(acpi_bus_scan);
1937
1938 /**
1939  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1940  * @adev: Root of the ACPI namespace scope to walk.
1941  *
1942  * Must be called under acpi_scan_lock.
1943  */
1944 void acpi_bus_trim(struct acpi_device *adev)
1945 {
1946         struct acpi_scan_handler *handler = adev->handler;
1947         struct acpi_device *child;
1948
1949         list_for_each_entry_reverse(child, &adev->children, node)
1950                 acpi_bus_trim(child);
1951
1952         adev->flags.match_driver = false;
1953         if (handler) {
1954                 if (handler->detach)
1955                         handler->detach(adev);
1956
1957                 adev->handler = NULL;
1958         } else {
1959                 device_release_driver(&adev->dev);
1960         }
1961         /*
1962          * Most likely, the device is going away, so put it into D3cold before
1963          * that.
1964          */
1965         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1966         adev->flags.initialized = false;
1967         acpi_device_clear_enumerated(adev);
1968 }
1969 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1970
1971 static int acpi_bus_scan_fixed(void)
1972 {
1973         int result = 0;
1974
1975         /*
1976          * Enumerate all fixed-feature devices.
1977          */
1978         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1979                 struct acpi_device *device = NULL;
1980
1981                 result = acpi_add_single_object(&device, NULL,
1982                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1983                                                 ACPI_STA_DEFAULT);
1984                 if (result)
1985                         return result;
1986
1987                 device->flags.match_driver = true;
1988                 result = device_attach(&device->dev);
1989                 if (result < 0)
1990                         return result;
1991
1992                 device_init_wakeup(&device->dev, true);
1993         }
1994
1995         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1996                 struct acpi_device *device = NULL;
1997
1998                 result = acpi_add_single_object(&device, NULL,
1999                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2000                                                 ACPI_STA_DEFAULT);
2001                 if (result)
2002                         return result;
2003
2004                 device->flags.match_driver = true;
2005                 result = device_attach(&device->dev);
2006         }
2007
2008         return result < 0 ? result : 0;
2009 }
2010
2011 static void __init acpi_get_spcr_uart_addr(void)
2012 {
2013         acpi_status status;
2014         struct acpi_table_spcr *spcr_ptr;
2015
2016         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2017                                 (struct acpi_table_header **)&spcr_ptr);
2018         if (ACPI_SUCCESS(status))
2019                 spcr_uart_addr = spcr_ptr->serial_port.address;
2020         else
2021                 printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2022 }
2023
2024 static bool acpi_scan_initialized;
2025
2026 int __init acpi_scan_init(void)
2027 {
2028         int result;
2029         acpi_status status;
2030         struct acpi_table_stao *stao_ptr;
2031
2032         acpi_pci_root_init();
2033         acpi_pci_link_init();
2034         acpi_processor_init();
2035         acpi_lpss_init();
2036         acpi_apd_init();
2037         acpi_cmos_rtc_init();
2038         acpi_container_init();
2039         acpi_memory_hotplug_init();
2040         acpi_pnp_init();
2041         acpi_int340x_thermal_init();
2042         acpi_amba_init();
2043         acpi_watchdog_init();
2044
2045         acpi_scan_add_handler(&generic_device_handler);
2046
2047         /*
2048          * If there is STAO table, check whether it needs to ignore the UART
2049          * device in SPCR table.
2050          */
2051         status = acpi_get_table(ACPI_SIG_STAO, 0,
2052                                 (struct acpi_table_header **)&stao_ptr);
2053         if (ACPI_SUCCESS(status)) {
2054                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2055                         printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2056
2057                 if (stao_ptr->ignore_uart)
2058                         acpi_get_spcr_uart_addr();
2059         }
2060
2061         mutex_lock(&acpi_scan_lock);
2062         /*
2063          * Enumerate devices in the ACPI namespace.
2064          */
2065         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2066         if (result)
2067                 goto out;
2068
2069         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2070         if (result)
2071                 goto out;
2072
2073         /* Fixed feature devices do not exist on HW-reduced platform */
2074         if (!acpi_gbl_reduced_hardware) {
2075                 result = acpi_bus_scan_fixed();
2076                 if (result) {
2077                         acpi_detach_data(acpi_root->handle,
2078                                          acpi_scan_drop_device);
2079                         acpi_device_del(acpi_root);
2080                         put_device(&acpi_root->dev);
2081                         goto out;
2082                 }
2083         }
2084
2085         acpi_gpe_apply_masked_gpes();
2086         acpi_update_all_gpes();
2087         acpi_ec_ecdt_start();
2088
2089         acpi_scan_initialized = true;
2090
2091  out:
2092         mutex_unlock(&acpi_scan_lock);
2093         return result;
2094 }
2095
2096 static struct acpi_probe_entry *ape;
2097 static int acpi_probe_count;
2098 static DEFINE_MUTEX(acpi_probe_mutex);
2099
2100 static int __init acpi_match_madt(struct acpi_subtable_header *header,
2101                                   const unsigned long end)
2102 {
2103         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2104                 if (!ape->probe_subtbl(header, end))
2105                         acpi_probe_count++;
2106
2107         return 0;
2108 }
2109
2110 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2111 {
2112         int count = 0;
2113
2114         if (acpi_disabled)
2115                 return 0;
2116
2117         mutex_lock(&acpi_probe_mutex);
2118         for (ape = ap_head; nr; ape++, nr--) {
2119                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2120                         acpi_probe_count = 0;
2121                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2122                         count += acpi_probe_count;
2123                 } else {
2124                         int res;
2125                         res = acpi_table_parse(ape->id, ape->probe_table);
2126                         if (!res)
2127                                 count++;
2128                 }
2129         }
2130         mutex_unlock(&acpi_probe_mutex);
2131
2132         return count;
2133 }
2134
2135 struct acpi_table_events_work {
2136         struct work_struct work;
2137         void *table;
2138         u32 event;
2139 };
2140
2141 static void acpi_table_events_fn(struct work_struct *work)
2142 {
2143         struct acpi_table_events_work *tew;
2144
2145         tew = container_of(work, struct acpi_table_events_work, work);
2146
2147         if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2148                 acpi_scan_lock_acquire();
2149                 acpi_bus_scan(ACPI_ROOT_OBJECT);
2150                 acpi_scan_lock_release();
2151         }
2152
2153         kfree(tew);
2154 }
2155
2156 void acpi_scan_table_handler(u32 event, void *table, void *context)
2157 {
2158         struct acpi_table_events_work *tew;
2159
2160         if (!acpi_scan_initialized)
2161                 return;
2162
2163         if (event != ACPI_TABLE_EVENT_LOAD)
2164                 return;
2165
2166         tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2167         if (!tew)
2168                 return;
2169
2170         INIT_WORK(&tew->work, acpi_table_events_fn);
2171         tew->table = table;
2172         tew->event = event;
2173
2174         schedule_work(&tew->work);
2175 }
2176
2177 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2178 {
2179         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2180 }
2181 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2182
2183 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2184 {
2185         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2186 }
2187 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);