x86/acpi, x86/boot: Take RSDP address for boot params if available
[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 #include <linux/platform_data/x86/apple.h>
17
18 #include <asm/pgtable.h>
19
20 #include "internal.h"
21
22 #define _COMPONENT              ACPI_BUS_COMPONENT
23 ACPI_MODULE_NAME("scan");
24 extern struct acpi_device *acpi_root;
25
26 #define ACPI_BUS_CLASS                  "system_bus"
27 #define ACPI_BUS_HID                    "LNXSYBUS"
28 #define ACPI_BUS_DEVICE_NAME            "System Bus"
29
30 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
31
32 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
33
34 static const char *dummy_hid = "device";
35
36 static LIST_HEAD(acpi_dep_list);
37 static DEFINE_MUTEX(acpi_dep_list_lock);
38 LIST_HEAD(acpi_bus_id_list);
39 static DEFINE_MUTEX(acpi_scan_lock);
40 static LIST_HEAD(acpi_scan_handlers_list);
41 DEFINE_MUTEX(acpi_device_lock);
42 LIST_HEAD(acpi_wakeup_device_list);
43 static DEFINE_MUTEX(acpi_hp_context_lock);
44
45 /*
46  * The UART device described by the SPCR table is the only object which needs
47  * special-casing. Everything else is covered by ACPI namespace paths in STAO
48  * table.
49  */
50 static u64 spcr_uart_addr;
51
52 struct acpi_dep_data {
53         struct list_head node;
54         acpi_handle master;
55         acpi_handle slave;
56 };
57
58 void acpi_scan_lock_acquire(void)
59 {
60         mutex_lock(&acpi_scan_lock);
61 }
62 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
63
64 void acpi_scan_lock_release(void)
65 {
66         mutex_unlock(&acpi_scan_lock);
67 }
68 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
69
70 void acpi_lock_hp_context(void)
71 {
72         mutex_lock(&acpi_hp_context_lock);
73 }
74
75 void acpi_unlock_hp_context(void)
76 {
77         mutex_unlock(&acpi_hp_context_lock);
78 }
79
80 void acpi_initialize_hp_context(struct acpi_device *adev,
81                                 struct acpi_hotplug_context *hp,
82                                 int (*notify)(struct acpi_device *, u32),
83                                 void (*uevent)(struct acpi_device *, u32))
84 {
85         acpi_lock_hp_context();
86         hp->notify = notify;
87         hp->uevent = uevent;
88         acpi_set_hp_context(adev, hp);
89         acpi_unlock_hp_context();
90 }
91 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
92
93 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
94 {
95         if (!handler)
96                 return -EINVAL;
97
98         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
99         return 0;
100 }
101
102 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
103                                        const char *hotplug_profile_name)
104 {
105         int error;
106
107         error = acpi_scan_add_handler(handler);
108         if (error)
109                 return error;
110
111         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
112         return 0;
113 }
114
115 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
116 {
117         struct acpi_device_physical_node *pn;
118         bool offline = true;
119         char *envp[] = { "EVENT=offline", NULL };
120
121         /*
122          * acpi_container_offline() calls this for all of the container's
123          * children under the container's physical_node_lock lock.
124          */
125         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
126
127         list_for_each_entry(pn, &adev->physical_node_list, node)
128                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
129                         if (uevent)
130                                 kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
131
132                         offline = false;
133                         break;
134                 }
135
136         mutex_unlock(&adev->physical_node_lock);
137         return offline;
138 }
139
140 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
141                                     void **ret_p)
142 {
143         struct acpi_device *device = NULL;
144         struct acpi_device_physical_node *pn;
145         bool second_pass = (bool)data;
146         acpi_status status = AE_OK;
147
148         if (acpi_bus_get_device(handle, &device))
149                 return AE_OK;
150
151         if (device->handler && !device->handler->hotplug.enabled) {
152                 *ret_p = &device->dev;
153                 return AE_SUPPORT;
154         }
155
156         mutex_lock(&device->physical_node_lock);
157
158         list_for_each_entry(pn, &device->physical_node_list, node) {
159                 int ret;
160
161                 if (second_pass) {
162                         /* Skip devices offlined by the first pass. */
163                         if (pn->put_online)
164                                 continue;
165                 } else {
166                         pn->put_online = false;
167                 }
168                 ret = device_offline(pn->dev);
169                 if (ret >= 0) {
170                         pn->put_online = !ret;
171                 } else {
172                         *ret_p = pn->dev;
173                         if (second_pass) {
174                                 status = AE_ERROR;
175                                 break;
176                         }
177                 }
178         }
179
180         mutex_unlock(&device->physical_node_lock);
181
182         return status;
183 }
184
185 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
186                                    void **ret_p)
187 {
188         struct acpi_device *device = NULL;
189         struct acpi_device_physical_node *pn;
190
191         if (acpi_bus_get_device(handle, &device))
192                 return AE_OK;
193
194         mutex_lock(&device->physical_node_lock);
195
196         list_for_each_entry(pn, &device->physical_node_list, node)
197                 if (pn->put_online) {
198                         device_online(pn->dev);
199                         pn->put_online = false;
200                 }
201
202         mutex_unlock(&device->physical_node_lock);
203
204         return AE_OK;
205 }
206
207 static int acpi_scan_try_to_offline(struct acpi_device *device)
208 {
209         acpi_handle handle = device->handle;
210         struct device *errdev = NULL;
211         acpi_status status;
212
213         /*
214          * Carry out two passes here and ignore errors in the first pass,
215          * because if the devices in question are memory blocks and
216          * CONFIG_MEMCG is set, one of the blocks may hold data structures
217          * that the other blocks depend on, but it is not known in advance which
218          * block holds them.
219          *
220          * If the first pass is successful, the second one isn't needed, though.
221          */
222         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
223                                      NULL, acpi_bus_offline, (void *)false,
224                                      (void **)&errdev);
225         if (status == AE_SUPPORT) {
226                 dev_warn(errdev, "Offline disabled.\n");
227                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
228                                     acpi_bus_online, NULL, NULL, NULL);
229                 return -EPERM;
230         }
231         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
232         if (errdev) {
233                 errdev = NULL;
234                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
235                                     NULL, acpi_bus_offline, (void *)true,
236                                     (void **)&errdev);
237                 if (!errdev)
238                         acpi_bus_offline(handle, 0, (void *)true,
239                                          (void **)&errdev);
240
241                 if (errdev) {
242                         dev_warn(errdev, "Offline failed.\n");
243                         acpi_bus_online(handle, 0, NULL, NULL);
244                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
245                                             ACPI_UINT32_MAX, acpi_bus_online,
246                                             NULL, NULL, NULL);
247                         return -EBUSY;
248                 }
249         }
250         return 0;
251 }
252
253 static int acpi_scan_hot_remove(struct acpi_device *device)
254 {
255         acpi_handle handle = device->handle;
256         unsigned long long sta;
257         acpi_status status;
258
259         if (device->handler && device->handler->hotplug.demand_offline) {
260                 if (!acpi_scan_is_offline(device, true))
261                         return -EBUSY;
262         } else {
263                 int error = acpi_scan_try_to_offline(device);
264                 if (error)
265                         return error;
266         }
267
268         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
269                 "Hot-removing device %s...\n", dev_name(&device->dev)));
270
271         acpi_bus_trim(device);
272
273         acpi_evaluate_lck(handle, 0);
274         /*
275          * TBD: _EJD support.
276          */
277         status = acpi_evaluate_ej0(handle);
278         if (status == AE_NOT_FOUND)
279                 return -ENODEV;
280         else if (ACPI_FAILURE(status))
281                 return -EIO;
282
283         /*
284          * Verify if eject was indeed successful.  If not, log an error
285          * message.  No need to call _OST since _EJ0 call was made OK.
286          */
287         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
288         if (ACPI_FAILURE(status)) {
289                 acpi_handle_warn(handle,
290                         "Status check after eject failed (0x%x)\n", status);
291         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
292                 acpi_handle_warn(handle,
293                         "Eject incomplete - status 0x%llx\n", sta);
294         }
295
296         return 0;
297 }
298
299 static int acpi_scan_device_not_present(struct acpi_device *adev)
300 {
301         if (!acpi_device_enumerated(adev)) {
302                 dev_warn(&adev->dev, "Still not present\n");
303                 return -EALREADY;
304         }
305         acpi_bus_trim(adev);
306         return 0;
307 }
308
309 static int acpi_scan_device_check(struct acpi_device *adev)
310 {
311         int error;
312
313         acpi_bus_get_status(adev);
314         if (adev->status.present || adev->status.functional) {
315                 /*
316                  * This function is only called for device objects for which
317                  * matching scan handlers exist.  The only situation in which
318                  * the scan handler is not attached to this device object yet
319                  * is when the device has just appeared (either it wasn't
320                  * present at all before or it was removed and then added
321                  * again).
322                  */
323                 if (adev->handler) {
324                         dev_warn(&adev->dev, "Already enumerated\n");
325                         return -EALREADY;
326                 }
327                 error = acpi_bus_scan(adev->handle);
328                 if (error) {
329                         dev_warn(&adev->dev, "Namespace scan failure\n");
330                         return error;
331                 }
332                 if (!adev->handler) {
333                         dev_warn(&adev->dev, "Enumeration failure\n");
334                         error = -ENODEV;
335                 }
336         } else {
337                 error = acpi_scan_device_not_present(adev);
338         }
339         return error;
340 }
341
342 static int acpi_scan_bus_check(struct acpi_device *adev)
343 {
344         struct acpi_scan_handler *handler = adev->handler;
345         struct acpi_device *child;
346         int error;
347
348         acpi_bus_get_status(adev);
349         if (!(adev->status.present || adev->status.functional)) {
350                 acpi_scan_device_not_present(adev);
351                 return 0;
352         }
353         if (handler && handler->hotplug.scan_dependent)
354                 return handler->hotplug.scan_dependent(adev);
355
356         error = acpi_bus_scan(adev->handle);
357         if (error) {
358                 dev_warn(&adev->dev, "Namespace scan failure\n");
359                 return error;
360         }
361         list_for_each_entry(child, &adev->children, node) {
362                 error = acpi_scan_bus_check(child);
363                 if (error)
364                         return error;
365         }
366         return 0;
367 }
368
369 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
370 {
371         switch (type) {
372         case ACPI_NOTIFY_BUS_CHECK:
373                 return acpi_scan_bus_check(adev);
374         case ACPI_NOTIFY_DEVICE_CHECK:
375                 return acpi_scan_device_check(adev);
376         case ACPI_NOTIFY_EJECT_REQUEST:
377         case ACPI_OST_EC_OSPM_EJECT:
378                 if (adev->handler && !adev->handler->hotplug.enabled) {
379                         dev_info(&adev->dev, "Eject disabled\n");
380                         return -EPERM;
381                 }
382                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
383                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
384                 return acpi_scan_hot_remove(adev);
385         }
386         return -EINVAL;
387 }
388
389 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
390 {
391         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
392         int error = -ENODEV;
393
394         lock_device_hotplug();
395         mutex_lock(&acpi_scan_lock);
396
397         /*
398          * The device object's ACPI handle cannot become invalid as long as we
399          * are holding acpi_scan_lock, but it might have become invalid before
400          * that lock was acquired.
401          */
402         if (adev->handle == INVALID_ACPI_HANDLE)
403                 goto err_out;
404
405         if (adev->flags.is_dock_station) {
406                 error = dock_notify(adev, src);
407         } else if (adev->flags.hotplug_notify) {
408                 error = acpi_generic_hotplug_event(adev, src);
409         } else {
410                 int (*notify)(struct acpi_device *, u32);
411
412                 acpi_lock_hp_context();
413                 notify = adev->hp ? adev->hp->notify : NULL;
414                 acpi_unlock_hp_context();
415                 /*
416                  * There may be additional notify handlers for device objects
417                  * without the .event() callback, so ignore them here.
418                  */
419                 if (notify)
420                         error = notify(adev, src);
421                 else
422                         goto out;
423         }
424         switch (error) {
425         case 0:
426                 ost_code = ACPI_OST_SC_SUCCESS;
427                 break;
428         case -EPERM:
429                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
430                 break;
431         case -EBUSY:
432                 ost_code = ACPI_OST_SC_DEVICE_BUSY;
433                 break;
434         default:
435                 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
436                 break;
437         }
438
439  err_out:
440         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
441
442  out:
443         acpi_bus_put_acpi_device(adev);
444         mutex_unlock(&acpi_scan_lock);
445         unlock_device_hotplug();
446 }
447
448 static void acpi_free_power_resources_lists(struct acpi_device *device)
449 {
450         int i;
451
452         if (device->wakeup.flags.valid)
453                 acpi_power_resources_list_free(&device->wakeup.resources);
454
455         if (!device->power.flags.power_resources)
456                 return;
457
458         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
459                 struct acpi_device_power_state *ps = &device->power.states[i];
460                 acpi_power_resources_list_free(&ps->resources);
461         }
462 }
463
464 static void acpi_device_release(struct device *dev)
465 {
466         struct acpi_device *acpi_dev = to_acpi_device(dev);
467
468         acpi_free_properties(acpi_dev);
469         acpi_free_pnp_ids(&acpi_dev->pnp);
470         acpi_free_power_resources_lists(acpi_dev);
471         kfree(acpi_dev);
472 }
473
474 static void acpi_device_del(struct acpi_device *device)
475 {
476         struct acpi_device_bus_id *acpi_device_bus_id;
477
478         mutex_lock(&acpi_device_lock);
479         if (device->parent)
480                 list_del(&device->node);
481
482         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
483                 if (!strcmp(acpi_device_bus_id->bus_id,
484                             acpi_device_hid(device))) {
485                         if (acpi_device_bus_id->instance_no > 0)
486                                 acpi_device_bus_id->instance_no--;
487                         else {
488                                 list_del(&acpi_device_bus_id->node);
489                                 kfree(acpi_device_bus_id);
490                         }
491                         break;
492                 }
493
494         list_del(&device->wakeup_list);
495         mutex_unlock(&acpi_device_lock);
496
497         acpi_power_add_remove_device(device, false);
498         acpi_device_remove_files(device);
499         if (device->remove)
500                 device->remove(device);
501
502         device_del(&device->dev);
503 }
504
505 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
506
507 static LIST_HEAD(acpi_device_del_list);
508 static DEFINE_MUTEX(acpi_device_del_lock);
509
510 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
511 {
512         for (;;) {
513                 struct acpi_device *adev;
514
515                 mutex_lock(&acpi_device_del_lock);
516
517                 if (list_empty(&acpi_device_del_list)) {
518                         mutex_unlock(&acpi_device_del_lock);
519                         break;
520                 }
521                 adev = list_first_entry(&acpi_device_del_list,
522                                         struct acpi_device, del_list);
523                 list_del(&adev->del_list);
524
525                 mutex_unlock(&acpi_device_del_lock);
526
527                 blocking_notifier_call_chain(&acpi_reconfig_chain,
528                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
529
530                 acpi_device_del(adev);
531                 /*
532                  * Drop references to all power resources that might have been
533                  * used by the device.
534                  */
535                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
536                 put_device(&adev->dev);
537         }
538 }
539
540 /**
541  * acpi_scan_drop_device - Drop an ACPI device object.
542  * @handle: Handle of an ACPI namespace node, not used.
543  * @context: Address of the ACPI device object to drop.
544  *
545  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
546  * namespace node the device object pointed to by @context is attached to.
547  *
548  * The unregistration is carried out asynchronously to avoid running
549  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
550  * ensure the correct ordering (the device objects must be unregistered in the
551  * same order in which the corresponding namespace nodes are deleted).
552  */
553 static void acpi_scan_drop_device(acpi_handle handle, void *context)
554 {
555         static DECLARE_WORK(work, acpi_device_del_work_fn);
556         struct acpi_device *adev = context;
557
558         mutex_lock(&acpi_device_del_lock);
559
560         /*
561          * Use the ACPI hotplug workqueue which is ordered, so this work item
562          * won't run after any hotplug work items submitted subsequently.  That
563          * prevents attempts to register device objects identical to those being
564          * deleted from happening concurrently (such attempts result from
565          * hotplug events handled via the ACPI hotplug workqueue).  It also will
566          * run after all of the work items submitted previosuly, which helps
567          * those work items to ensure that they are not accessing stale device
568          * objects.
569          */
570         if (list_empty(&acpi_device_del_list))
571                 acpi_queue_hotplug_work(&work);
572
573         list_add_tail(&adev->del_list, &acpi_device_del_list);
574         /* Make acpi_ns_validate_handle() return NULL for this handle. */
575         adev->handle = INVALID_ACPI_HANDLE;
576
577         mutex_unlock(&acpi_device_del_lock);
578 }
579
580 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
581                                 void (*callback)(void *))
582 {
583         acpi_status status;
584
585         if (!device)
586                 return -EINVAL;
587
588         status = acpi_get_data_full(handle, acpi_scan_drop_device,
589                                     (void **)device, callback);
590         if (ACPI_FAILURE(status) || !*device) {
591                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
592                                   handle));
593                 return -ENODEV;
594         }
595         return 0;
596 }
597
598 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
599 {
600         return acpi_get_device_data(handle, device, NULL);
601 }
602 EXPORT_SYMBOL(acpi_bus_get_device);
603
604 static void get_acpi_device(void *dev)
605 {
606         if (dev)
607                 get_device(&((struct acpi_device *)dev)->dev);
608 }
609
610 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
611 {
612         struct acpi_device *adev = NULL;
613
614         acpi_get_device_data(handle, &adev, get_acpi_device);
615         return adev;
616 }
617
618 void acpi_bus_put_acpi_device(struct acpi_device *adev)
619 {
620         put_device(&adev->dev);
621 }
622
623 int acpi_device_add(struct acpi_device *device,
624                     void (*release)(struct device *))
625 {
626         int result;
627         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
628         int found = 0;
629
630         if (device->handle) {
631                 acpi_status status;
632
633                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
634                                           device);
635                 if (ACPI_FAILURE(status)) {
636                         acpi_handle_err(device->handle,
637                                         "Unable to attach device data\n");
638                         return -ENODEV;
639                 }
640         }
641
642         /*
643          * Linkage
644          * -------
645          * Link this device to its parent and siblings.
646          */
647         INIT_LIST_HEAD(&device->children);
648         INIT_LIST_HEAD(&device->node);
649         INIT_LIST_HEAD(&device->wakeup_list);
650         INIT_LIST_HEAD(&device->physical_node_list);
651         INIT_LIST_HEAD(&device->del_list);
652         mutex_init(&device->physical_node_lock);
653
654         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
655         if (!new_bus_id) {
656                 pr_err(PREFIX "Memory allocation error\n");
657                 result = -ENOMEM;
658                 goto err_detach;
659         }
660
661         mutex_lock(&acpi_device_lock);
662         /*
663          * Find suitable bus_id and instance number in acpi_bus_id_list
664          * If failed, create one and link it into acpi_bus_id_list
665          */
666         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
667                 if (!strcmp(acpi_device_bus_id->bus_id,
668                             acpi_device_hid(device))) {
669                         acpi_device_bus_id->instance_no++;
670                         found = 1;
671                         kfree(new_bus_id);
672                         break;
673                 }
674         }
675         if (!found) {
676                 acpi_device_bus_id = new_bus_id;
677                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
678                 acpi_device_bus_id->instance_no = 0;
679                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
680         }
681         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
682
683         if (device->parent)
684                 list_add_tail(&device->node, &device->parent->children);
685
686         if (device->wakeup.flags.valid)
687                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
688         mutex_unlock(&acpi_device_lock);
689
690         if (device->parent)
691                 device->dev.parent = &device->parent->dev;
692         device->dev.bus = &acpi_bus_type;
693         device->dev.release = release;
694         result = device_add(&device->dev);
695         if (result) {
696                 dev_err(&device->dev, "Error registering device\n");
697                 goto err;
698         }
699
700         result = acpi_device_setup_files(device);
701         if (result)
702                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
703                        dev_name(&device->dev));
704
705         return 0;
706
707  err:
708         mutex_lock(&acpi_device_lock);
709         if (device->parent)
710                 list_del(&device->node);
711         list_del(&device->wakeup_list);
712         mutex_unlock(&acpi_device_lock);
713
714  err_detach:
715         acpi_detach_data(device->handle, acpi_scan_drop_device);
716         return result;
717 }
718
719 /* --------------------------------------------------------------------------
720                                  Device Enumeration
721    -------------------------------------------------------------------------- */
722 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
723 {
724         struct acpi_device *device = NULL;
725         acpi_status status;
726
727         /*
728          * Fixed hardware devices do not appear in the namespace and do not
729          * have handles, but we fabricate acpi_devices for them, so we have
730          * to deal with them specially.
731          */
732         if (!handle)
733                 return acpi_root;
734
735         do {
736                 status = acpi_get_parent(handle, &handle);
737                 if (ACPI_FAILURE(status))
738                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
739         } while (acpi_bus_get_device(handle, &device));
740         return device;
741 }
742
743 acpi_status
744 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
745 {
746         acpi_status status;
747         acpi_handle tmp;
748         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
749         union acpi_object *obj;
750
751         status = acpi_get_handle(handle, "_EJD", &tmp);
752         if (ACPI_FAILURE(status))
753                 return status;
754
755         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
756         if (ACPI_SUCCESS(status)) {
757                 obj = buffer.pointer;
758                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
759                                          ejd);
760                 kfree(buffer.pointer);
761         }
762         return status;
763 }
764 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
765
766 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
767                                         struct acpi_device_wakeup *wakeup)
768 {
769         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
770         union acpi_object *package = NULL;
771         union acpi_object *element = NULL;
772         acpi_status status;
773         int err = -ENODATA;
774
775         if (!wakeup)
776                 return -EINVAL;
777
778         INIT_LIST_HEAD(&wakeup->resources);
779
780         /* _PRW */
781         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
782         if (ACPI_FAILURE(status)) {
783                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
784                 return err;
785         }
786
787         package = (union acpi_object *)buffer.pointer;
788
789         if (!package || package->package.count < 2)
790                 goto out;
791
792         element = &(package->package.elements[0]);
793         if (!element)
794                 goto out;
795
796         if (element->type == ACPI_TYPE_PACKAGE) {
797                 if ((element->package.count < 2) ||
798                     (element->package.elements[0].type !=
799                      ACPI_TYPE_LOCAL_REFERENCE)
800                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
801                         goto out;
802
803                 wakeup->gpe_device =
804                     element->package.elements[0].reference.handle;
805                 wakeup->gpe_number =
806                     (u32) element->package.elements[1].integer.value;
807         } else if (element->type == ACPI_TYPE_INTEGER) {
808                 wakeup->gpe_device = NULL;
809                 wakeup->gpe_number = element->integer.value;
810         } else {
811                 goto out;
812         }
813
814         element = &(package->package.elements[1]);
815         if (element->type != ACPI_TYPE_INTEGER)
816                 goto out;
817
818         wakeup->sleep_state = element->integer.value;
819
820         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
821         if (err)
822                 goto out;
823
824         if (!list_empty(&wakeup->resources)) {
825                 int sleep_state;
826
827                 err = acpi_power_wakeup_list_init(&wakeup->resources,
828                                                   &sleep_state);
829                 if (err) {
830                         acpi_handle_warn(handle, "Retrieving current states "
831                                          "of wakeup power resources failed\n");
832                         acpi_power_resources_list_free(&wakeup->resources);
833                         goto out;
834                 }
835                 if (sleep_state < wakeup->sleep_state) {
836                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
837                                          "(S%d) by S%d from power resources\n",
838                                          (int)wakeup->sleep_state, sleep_state);
839                         wakeup->sleep_state = sleep_state;
840                 }
841         }
842
843  out:
844         kfree(buffer.pointer);
845         return err;
846 }
847
848 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
849 {
850         static const struct acpi_device_id button_device_ids[] = {
851                 {"PNP0C0C", 0},
852                 {"PNP0C0D", 0},
853                 {"PNP0C0E", 0},
854                 {"", 0},
855         };
856         struct acpi_device_wakeup *wakeup = &device->wakeup;
857         acpi_status status;
858
859         wakeup->flags.notifier_present = 0;
860
861         /* Power button, Lid switch always enable wakeup */
862         if (!acpi_match_device_ids(device, button_device_ids)) {
863                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
864                         /* Do not use Lid/sleep button for S5 wakeup */
865                         if (wakeup->sleep_state == ACPI_STATE_S5)
866                                 wakeup->sleep_state = ACPI_STATE_S4;
867                 }
868                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
869                 device_set_wakeup_capable(&device->dev, true);
870                 return true;
871         }
872
873         status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
874                                          wakeup->gpe_number);
875         return ACPI_SUCCESS(status);
876 }
877
878 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
879 {
880         int err;
881
882         /* Presence of _PRW indicates wake capable */
883         if (!acpi_has_method(device->handle, "_PRW"))
884                 return;
885
886         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
887                                                            &device->wakeup);
888         if (err) {
889                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
890                 return;
891         }
892
893         device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
894         device->wakeup.prepare_count = 0;
895         /*
896          * Call _PSW/_DSW object to disable its ability to wake the sleeping
897          * system for the ACPI device with the _PRW object.
898          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
899          * So it is necessary to call _DSW object first. Only when it is not
900          * present will the _PSW object used.
901          */
902         err = acpi_device_sleep_wake(device, 0, 0, 0);
903         if (err)
904                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
905                                 "error in _DSW or _PSW evaluation\n"));
906 }
907
908 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
909 {
910         struct acpi_device_power_state *ps = &device->power.states[state];
911         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
912         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
913         acpi_status status;
914
915         INIT_LIST_HEAD(&ps->resources);
916
917         /* Evaluate "_PRx" to get referenced power resources */
918         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
919         if (ACPI_SUCCESS(status)) {
920                 union acpi_object *package = buffer.pointer;
921
922                 if (buffer.length && package
923                     && package->type == ACPI_TYPE_PACKAGE
924                     && package->package.count) {
925                         int err = acpi_extract_power_resources(package, 0,
926                                                                &ps->resources);
927                         if (!err)
928                                 device->power.flags.power_resources = 1;
929                 }
930                 ACPI_FREE(buffer.pointer);
931         }
932
933         /* Evaluate "_PSx" to see if we can do explicit sets */
934         pathname[2] = 'S';
935         if (acpi_has_method(device->handle, pathname))
936                 ps->flags.explicit_set = 1;
937
938         /* State is valid if there are means to put the device into it. */
939         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
940                 ps->flags.valid = 1;
941
942         ps->power = -1;         /* Unknown - driver assigned */
943         ps->latency = -1;       /* Unknown - driver assigned */
944 }
945
946 static void acpi_bus_get_power_flags(struct acpi_device *device)
947 {
948         u32 i;
949
950         /* Presence of _PS0|_PR0 indicates 'power manageable' */
951         if (!acpi_has_method(device->handle, "_PS0") &&
952             !acpi_has_method(device->handle, "_PR0"))
953                 return;
954
955         device->flags.power_manageable = 1;
956
957         /*
958          * Power Management Flags
959          */
960         if (acpi_has_method(device->handle, "_PSC"))
961                 device->power.flags.explicit_get = 1;
962
963         if (acpi_has_method(device->handle, "_IRC"))
964                 device->power.flags.inrush_current = 1;
965
966         if (acpi_has_method(device->handle, "_DSW"))
967                 device->power.flags.dsw_present = 1;
968
969         /*
970          * Enumerate supported power management states
971          */
972         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
973                 acpi_bus_init_power_state(device, i);
974
975         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
976         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
977                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
978
979         /* Set defaults for D0 and D3hot states (always valid) */
980         device->power.states[ACPI_STATE_D0].flags.valid = 1;
981         device->power.states[ACPI_STATE_D0].power = 100;
982         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
983
984         if (acpi_bus_init_power(device))
985                 device->flags.power_manageable = 0;
986 }
987
988 static void acpi_bus_get_flags(struct acpi_device *device)
989 {
990         /* Presence of _STA indicates 'dynamic_status' */
991         if (acpi_has_method(device->handle, "_STA"))
992                 device->flags.dynamic_status = 1;
993
994         /* Presence of _RMV indicates 'removable' */
995         if (acpi_has_method(device->handle, "_RMV"))
996                 device->flags.removable = 1;
997
998         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
999         if (acpi_has_method(device->handle, "_EJD") ||
1000             acpi_has_method(device->handle, "_EJ0"))
1001                 device->flags.ejectable = 1;
1002 }
1003
1004 static void acpi_device_get_busid(struct acpi_device *device)
1005 {
1006         char bus_id[5] = { '?', 0 };
1007         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1008         int i = 0;
1009
1010         /*
1011          * Bus ID
1012          * ------
1013          * The device's Bus ID is simply the object name.
1014          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1015          */
1016         if (ACPI_IS_ROOT_DEVICE(device)) {
1017                 strcpy(device->pnp.bus_id, "ACPI");
1018                 return;
1019         }
1020
1021         switch (device->device_type) {
1022         case ACPI_BUS_TYPE_POWER_BUTTON:
1023                 strcpy(device->pnp.bus_id, "PWRF");
1024                 break;
1025         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1026                 strcpy(device->pnp.bus_id, "SLPF");
1027                 break;
1028         case ACPI_BUS_TYPE_ECDT_EC:
1029                 strcpy(device->pnp.bus_id, "ECDT");
1030                 break;
1031         default:
1032                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1033                 /* Clean up trailing underscores (if any) */
1034                 for (i = 3; i > 1; i--) {
1035                         if (bus_id[i] == '_')
1036                                 bus_id[i] = '\0';
1037                         else
1038                                 break;
1039                 }
1040                 strcpy(device->pnp.bus_id, bus_id);
1041                 break;
1042         }
1043 }
1044
1045 /*
1046  * acpi_ata_match - see if an acpi object is an ATA device
1047  *
1048  * If an acpi object has one of the ACPI ATA methods defined,
1049  * then we can safely call it an ATA device.
1050  */
1051 bool acpi_ata_match(acpi_handle handle)
1052 {
1053         return acpi_has_method(handle, "_GTF") ||
1054                acpi_has_method(handle, "_GTM") ||
1055                acpi_has_method(handle, "_STM") ||
1056                acpi_has_method(handle, "_SDD");
1057 }
1058
1059 /*
1060  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1061  *
1062  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1063  * then we can safely call it an ejectable drive bay
1064  */
1065 bool acpi_bay_match(acpi_handle handle)
1066 {
1067         acpi_handle phandle;
1068
1069         if (!acpi_has_method(handle, "_EJ0"))
1070                 return false;
1071         if (acpi_ata_match(handle))
1072                 return true;
1073         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1074                 return false;
1075
1076         return acpi_ata_match(phandle);
1077 }
1078
1079 bool acpi_device_is_battery(struct acpi_device *adev)
1080 {
1081         struct acpi_hardware_id *hwid;
1082
1083         list_for_each_entry(hwid, &adev->pnp.ids, list)
1084                 if (!strcmp("PNP0C0A", hwid->id))
1085                         return true;
1086
1087         return false;
1088 }
1089
1090 static bool is_ejectable_bay(struct acpi_device *adev)
1091 {
1092         acpi_handle handle = adev->handle;
1093
1094         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1095                 return true;
1096
1097         return acpi_bay_match(handle);
1098 }
1099
1100 /*
1101  * acpi_dock_match - see if an acpi object has a _DCK method
1102  */
1103 bool acpi_dock_match(acpi_handle handle)
1104 {
1105         return acpi_has_method(handle, "_DCK");
1106 }
1107
1108 static acpi_status
1109 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1110                           void **return_value)
1111 {
1112         long *cap = context;
1113
1114         if (acpi_has_method(handle, "_BCM") &&
1115             acpi_has_method(handle, "_BCL")) {
1116                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1117                                   "support\n"));
1118                 *cap |= ACPI_VIDEO_BACKLIGHT;
1119                 /* We have backlight support, no need to scan further */
1120                 return AE_CTRL_TERMINATE;
1121         }
1122         return 0;
1123 }
1124
1125 /* Returns true if the ACPI object is a video device which can be
1126  * handled by video.ko.
1127  * The device will get a Linux specific CID added in scan.c to
1128  * identify the device as an ACPI graphics device
1129  * Be aware that the graphics device may not be physically present
1130  * Use acpi_video_get_capabilities() to detect general ACPI video
1131  * capabilities of present cards
1132  */
1133 long acpi_is_video_device(acpi_handle handle)
1134 {
1135         long video_caps = 0;
1136
1137         /* Is this device able to support video switching ? */
1138         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1139                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1140
1141         /* Is this device able to retrieve a video ROM ? */
1142         if (acpi_has_method(handle, "_ROM"))
1143                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1144
1145         /* Is this device able to configure which video head to be POSTed ? */
1146         if (acpi_has_method(handle, "_VPO") &&
1147             acpi_has_method(handle, "_GPD") &&
1148             acpi_has_method(handle, "_SPD"))
1149                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1150
1151         /* Only check for backlight functionality if one of the above hit. */
1152         if (video_caps)
1153                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1154                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1155                                     &video_caps, NULL);
1156
1157         return video_caps;
1158 }
1159 EXPORT_SYMBOL(acpi_is_video_device);
1160
1161 const char *acpi_device_hid(struct acpi_device *device)
1162 {
1163         struct acpi_hardware_id *hid;
1164
1165         if (list_empty(&device->pnp.ids))
1166                 return dummy_hid;
1167
1168         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1169         return hid->id;
1170 }
1171 EXPORT_SYMBOL(acpi_device_hid);
1172
1173 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1174 {
1175         struct acpi_hardware_id *id;
1176
1177         id = kmalloc(sizeof(*id), GFP_KERNEL);
1178         if (!id)
1179                 return;
1180
1181         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1182         if (!id->id) {
1183                 kfree(id);
1184                 return;
1185         }
1186
1187         list_add_tail(&id->list, &pnp->ids);
1188         pnp->type.hardware_id = 1;
1189 }
1190
1191 /*
1192  * Old IBM workstations have a DSDT bug wherein the SMBus object
1193  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1194  * prefix.  Work around this.
1195  */
1196 static bool acpi_ibm_smbus_match(acpi_handle handle)
1197 {
1198         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1199         struct acpi_buffer path = { sizeof(node_name), node_name };
1200
1201         if (!dmi_name_in_vendors("IBM"))
1202                 return false;
1203
1204         /* Look for SMBS object */
1205         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1206             strcmp("SMBS", path.pointer))
1207                 return false;
1208
1209         /* Does it have the necessary (but misnamed) methods? */
1210         if (acpi_has_method(handle, "SBI") &&
1211             acpi_has_method(handle, "SBR") &&
1212             acpi_has_method(handle, "SBW"))
1213                 return true;
1214
1215         return false;
1216 }
1217
1218 static bool acpi_object_is_system_bus(acpi_handle handle)
1219 {
1220         acpi_handle tmp;
1221
1222         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1223             tmp == handle)
1224                 return true;
1225         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1226             tmp == handle)
1227                 return true;
1228
1229         return false;
1230 }
1231
1232 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1233                                 int device_type)
1234 {
1235         acpi_status status;
1236         struct acpi_device_info *info;
1237         struct acpi_pnp_device_id_list *cid_list;
1238         int i;
1239
1240         switch (device_type) {
1241         case ACPI_BUS_TYPE_DEVICE:
1242                 if (handle == ACPI_ROOT_OBJECT) {
1243                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1244                         break;
1245                 }
1246
1247                 status = acpi_get_object_info(handle, &info);
1248                 if (ACPI_FAILURE(status)) {
1249                         pr_err(PREFIX "%s: Error reading device info\n",
1250                                         __func__);
1251                         return;
1252                 }
1253
1254                 if (info->valid & ACPI_VALID_HID) {
1255                         acpi_add_id(pnp, info->hardware_id.string);
1256                         pnp->type.platform_id = 1;
1257                 }
1258                 if (info->valid & ACPI_VALID_CID) {
1259                         cid_list = &info->compatible_id_list;
1260                         for (i = 0; i < cid_list->count; i++)
1261                                 acpi_add_id(pnp, cid_list->ids[i].string);
1262                 }
1263                 if (info->valid & ACPI_VALID_ADR) {
1264                         pnp->bus_address = info->address;
1265                         pnp->type.bus_address = 1;
1266                 }
1267                 if (info->valid & ACPI_VALID_UID)
1268                         pnp->unique_id = kstrdup(info->unique_id.string,
1269                                                         GFP_KERNEL);
1270                 if (info->valid & ACPI_VALID_CLS)
1271                         acpi_add_id(pnp, info->class_code.string);
1272
1273                 kfree(info);
1274
1275                 /*
1276                  * Some devices don't reliably have _HIDs & _CIDs, so add
1277                  * synthetic HIDs to make sure drivers can find them.
1278                  */
1279                 if (acpi_is_video_device(handle))
1280                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1281                 else if (acpi_bay_match(handle))
1282                         acpi_add_id(pnp, ACPI_BAY_HID);
1283                 else if (acpi_dock_match(handle))
1284                         acpi_add_id(pnp, ACPI_DOCK_HID);
1285                 else if (acpi_ibm_smbus_match(handle))
1286                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1287                 else if (list_empty(&pnp->ids) &&
1288                          acpi_object_is_system_bus(handle)) {
1289                         /* \_SB, \_TZ, LNXSYBUS */
1290                         acpi_add_id(pnp, ACPI_BUS_HID);
1291                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1292                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1293                 }
1294
1295                 break;
1296         case ACPI_BUS_TYPE_POWER:
1297                 acpi_add_id(pnp, ACPI_POWER_HID);
1298                 break;
1299         case ACPI_BUS_TYPE_PROCESSOR:
1300                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1301                 break;
1302         case ACPI_BUS_TYPE_THERMAL:
1303                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1304                 break;
1305         case ACPI_BUS_TYPE_POWER_BUTTON:
1306                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1307                 break;
1308         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1309                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1310                 break;
1311         case ACPI_BUS_TYPE_ECDT_EC:
1312                 acpi_add_id(pnp, ACPI_ECDT_HID);
1313                 break;
1314         }
1315 }
1316
1317 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1318 {
1319         struct acpi_hardware_id *id, *tmp;
1320
1321         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1322                 kfree_const(id->id);
1323                 kfree(id);
1324         }
1325         kfree(pnp->unique_id);
1326 }
1327
1328 /**
1329  * acpi_dma_supported - Check DMA support for the specified device.
1330  * @adev: The pointer to acpi device
1331  *
1332  * Return false if DMA is not supported. Otherwise, return true
1333  */
1334 bool acpi_dma_supported(struct acpi_device *adev)
1335 {
1336         if (!adev)
1337                 return false;
1338
1339         if (adev->flags.cca_seen)
1340                 return true;
1341
1342         /*
1343         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1344         * DMA on "Intel platforms".  Presumably that includes all x86 and
1345         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1346         */
1347         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1348                 return true;
1349
1350         return false;
1351 }
1352
1353 /**
1354  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1355  * @adev: The pointer to acpi device
1356  *
1357  * Return enum dev_dma_attr.
1358  */
1359 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1360 {
1361         if (!acpi_dma_supported(adev))
1362                 return DEV_DMA_NOT_SUPPORTED;
1363
1364         if (adev->flags.coherent_dma)
1365                 return DEV_DMA_COHERENT;
1366         else
1367                 return DEV_DMA_NON_COHERENT;
1368 }
1369
1370 /**
1371  * acpi_dma_get_range() - Get device DMA parameters.
1372  *
1373  * @dev: device to configure
1374  * @dma_addr: pointer device DMA address result
1375  * @offset: pointer to the DMA offset result
1376  * @size: pointer to DMA range size result
1377  *
1378  * Evaluate DMA regions and return respectively DMA region start, offset
1379  * and size in dma_addr, offset and size on parsing success; it does not
1380  * update the passed in values on failure.
1381  *
1382  * Return 0 on success, < 0 on failure.
1383  */
1384 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1385                        u64 *size)
1386 {
1387         struct acpi_device *adev;
1388         LIST_HEAD(list);
1389         struct resource_entry *rentry;
1390         int ret;
1391         struct device *dma_dev = dev;
1392         u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1393
1394         /*
1395          * Walk the device tree chasing an ACPI companion with a _DMA
1396          * object while we go. Stop if we find a device with an ACPI
1397          * companion containing a _DMA method.
1398          */
1399         do {
1400                 adev = ACPI_COMPANION(dma_dev);
1401                 if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1402                         break;
1403
1404                 dma_dev = dma_dev->parent;
1405         } while (dma_dev);
1406
1407         if (!dma_dev)
1408                 return -ENODEV;
1409
1410         if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1411                 acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1412                 return -EINVAL;
1413         }
1414
1415         ret = acpi_dev_get_dma_resources(adev, &list);
1416         if (ret > 0) {
1417                 list_for_each_entry(rentry, &list, node) {
1418                         if (dma_offset && rentry->offset != dma_offset) {
1419                                 ret = -EINVAL;
1420                                 dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1421                                 goto out;
1422                         }
1423                         dma_offset = rentry->offset;
1424
1425                         /* Take lower and upper limits */
1426                         if (rentry->res->start < dma_start)
1427                                 dma_start = rentry->res->start;
1428                         if (rentry->res->end > dma_end)
1429                                 dma_end = rentry->res->end;
1430                 }
1431
1432                 if (dma_start >= dma_end) {
1433                         ret = -EINVAL;
1434                         dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1435                         goto out;
1436                 }
1437
1438                 *dma_addr = dma_start - dma_offset;
1439                 len = dma_end - dma_start;
1440                 *size = max(len, len + 1);
1441                 *offset = dma_offset;
1442         }
1443  out:
1444         acpi_dev_free_resource_list(&list);
1445
1446         return ret >= 0 ? 0 : ret;
1447 }
1448
1449 /**
1450  * acpi_dma_configure - Set-up DMA configuration for the device.
1451  * @dev: The pointer to the device
1452  * @attr: device dma attributes
1453  */
1454 int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1455 {
1456         const struct iommu_ops *iommu;
1457         u64 dma_addr = 0, size = 0;
1458
1459         iort_dma_setup(dev, &dma_addr, &size);
1460
1461         iommu = iort_iommu_configure(dev);
1462         if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1463                 return -EPROBE_DEFER;
1464
1465         arch_setup_dma_ops(dev, dma_addr, size,
1466                                 iommu, attr == DEV_DMA_COHERENT);
1467
1468         return 0;
1469 }
1470 EXPORT_SYMBOL_GPL(acpi_dma_configure);
1471
1472 /**
1473  * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1474  * @dev: The pointer to the device
1475  */
1476 void acpi_dma_deconfigure(struct device *dev)
1477 {
1478         arch_teardown_dma_ops(dev);
1479 }
1480 EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1481
1482 static void acpi_init_coherency(struct acpi_device *adev)
1483 {
1484         unsigned long long cca = 0;
1485         acpi_status status;
1486         struct acpi_device *parent = adev->parent;
1487
1488         if (parent && parent->flags.cca_seen) {
1489                 /*
1490                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1491                  * already saw one.
1492                  */
1493                 adev->flags.cca_seen = 1;
1494                 cca = parent->flags.coherent_dma;
1495         } else {
1496                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1497                                                NULL, &cca);
1498                 if (ACPI_SUCCESS(status))
1499                         adev->flags.cca_seen = 1;
1500                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1501                         /*
1502                          * If architecture does not specify that _CCA is
1503                          * required for DMA-able devices (e.g. x86),
1504                          * we default to _CCA=1.
1505                          */
1506                         cca = 1;
1507                 else
1508                         acpi_handle_debug(adev->handle,
1509                                           "ACPI device is missing _CCA.\n");
1510         }
1511
1512         adev->flags.coherent_dma = cca;
1513 }
1514
1515 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1516 {
1517         bool *is_serial_bus_slave_p = data;
1518
1519         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1520                 return 1;
1521
1522         *is_serial_bus_slave_p = true;
1523
1524          /* no need to do more checking */
1525         return -1;
1526 }
1527
1528 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1529 {
1530         struct acpi_device *parent = device->parent;
1531         static const struct acpi_device_id indirect_io_hosts[] = {
1532                 {"HISI0191", 0},
1533                 {}
1534         };
1535
1536         return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1537 }
1538
1539 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1540 {
1541         struct list_head resource_list;
1542         bool is_serial_bus_slave = false;
1543         /*
1544          * These devices have multiple I2cSerialBus resources and an i2c-client
1545          * must be instantiated for each, each with its own i2c_device_id.
1546          * Normally we only instantiate an i2c-client for the first resource,
1547          * using the ACPI HID as id. These special cases are handled by the
1548          * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1549          * which i2c_device_id to use for each resource.
1550          */
1551         static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1552                 {"BSG1160", },
1553                 {}
1554         };
1555
1556         if (acpi_is_indirect_io_slave(device))
1557                 return true;
1558
1559         /* Macs use device properties in lieu of _CRS resources */
1560         if (x86_apple_machine &&
1561             (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1562              fwnode_property_present(&device->fwnode, "i2cAddress") ||
1563              fwnode_property_present(&device->fwnode, "baud")))
1564                 return true;
1565
1566         /* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1567         if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1568                 return false;
1569
1570         INIT_LIST_HEAD(&resource_list);
1571         acpi_dev_get_resources(device, &resource_list,
1572                                acpi_check_serial_bus_slave,
1573                                &is_serial_bus_slave);
1574         acpi_dev_free_resource_list(&resource_list);
1575
1576         return is_serial_bus_slave;
1577 }
1578
1579 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1580                              int type, unsigned long long sta)
1581 {
1582         INIT_LIST_HEAD(&device->pnp.ids);
1583         device->device_type = type;
1584         device->handle = handle;
1585         device->parent = acpi_bus_get_parent(handle);
1586         device->fwnode.ops = &acpi_device_fwnode_ops;
1587         acpi_set_device_status(device, sta);
1588         acpi_device_get_busid(device);
1589         acpi_set_pnp_ids(handle, &device->pnp, type);
1590         acpi_init_properties(device);
1591         acpi_bus_get_flags(device);
1592         device->flags.match_driver = false;
1593         device->flags.initialized = true;
1594         device->flags.enumeration_by_parent =
1595                 acpi_device_enumeration_by_parent(device);
1596         acpi_device_clear_enumerated(device);
1597         device_initialize(&device->dev);
1598         dev_set_uevent_suppress(&device->dev, true);
1599         acpi_init_coherency(device);
1600         /* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1601         device->dep_unmet = 1;
1602 }
1603
1604 void acpi_device_add_finalize(struct acpi_device *device)
1605 {
1606         dev_set_uevent_suppress(&device->dev, false);
1607         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1608 }
1609
1610 static int acpi_add_single_object(struct acpi_device **child,
1611                                   acpi_handle handle, int type,
1612                                   unsigned long long sta)
1613 {
1614         int result;
1615         struct acpi_device *device;
1616         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1617
1618         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1619         if (!device) {
1620                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1621                 return -ENOMEM;
1622         }
1623
1624         acpi_init_device_object(device, handle, type, sta);
1625         /*
1626          * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1627          * that we can call acpi_bus_get_status() and use its quirk handling.
1628          * Note this must be done before the get power-/wakeup_dev-flags calls.
1629          */
1630         if (type == ACPI_BUS_TYPE_DEVICE)
1631                 if (acpi_bus_get_status(device) < 0)
1632                         acpi_set_device_status(device, 0);
1633
1634         acpi_bus_get_power_flags(device);
1635         acpi_bus_get_wakeup_device_flags(device);
1636
1637         result = acpi_device_add(device, acpi_device_release);
1638         if (result) {
1639                 acpi_device_release(&device->dev);
1640                 return result;
1641         }
1642
1643         acpi_power_add_remove_device(device, true);
1644         acpi_device_add_finalize(device);
1645         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1646         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1647                 dev_name(&device->dev), (char *) buffer.pointer,
1648                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1649         kfree(buffer.pointer);
1650         *child = device;
1651         return 0;
1652 }
1653
1654 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1655                                             void *context)
1656 {
1657         struct resource *res = context;
1658
1659         if (acpi_dev_resource_memory(ares, res))
1660                 return AE_CTRL_TERMINATE;
1661
1662         return AE_OK;
1663 }
1664
1665 static bool acpi_device_should_be_hidden(acpi_handle handle)
1666 {
1667         acpi_status status;
1668         struct resource res;
1669
1670         /* Check if it should ignore the UART device */
1671         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1672                 return false;
1673
1674         /*
1675          * The UART device described in SPCR table is assumed to have only one
1676          * memory resource present. So we only look for the first one here.
1677          */
1678         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1679                                      acpi_get_resource_memory, &res);
1680         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1681                 return false;
1682
1683         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1684                          &res.start);
1685
1686         return true;
1687 }
1688
1689 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1690                                     unsigned long long *sta)
1691 {
1692         acpi_status status;
1693         acpi_object_type acpi_type;
1694
1695         status = acpi_get_type(handle, &acpi_type);
1696         if (ACPI_FAILURE(status))
1697                 return -ENODEV;
1698
1699         switch (acpi_type) {
1700         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1701         case ACPI_TYPE_DEVICE:
1702                 if (acpi_device_should_be_hidden(handle))
1703                         return -ENODEV;
1704
1705                 *type = ACPI_BUS_TYPE_DEVICE;
1706                 /*
1707                  * acpi_add_single_object updates this once we've an acpi_device
1708                  * so that acpi_bus_get_status' quirk handling can be used.
1709                  */
1710                 *sta = ACPI_STA_DEFAULT;
1711                 break;
1712         case ACPI_TYPE_PROCESSOR:
1713                 *type = ACPI_BUS_TYPE_PROCESSOR;
1714                 status = acpi_bus_get_status_handle(handle, sta);
1715                 if (ACPI_FAILURE(status))
1716                         return -ENODEV;
1717                 break;
1718         case ACPI_TYPE_THERMAL:
1719                 *type = ACPI_BUS_TYPE_THERMAL;
1720                 *sta = ACPI_STA_DEFAULT;
1721                 break;
1722         case ACPI_TYPE_POWER:
1723                 *type = ACPI_BUS_TYPE_POWER;
1724                 *sta = ACPI_STA_DEFAULT;
1725                 break;
1726         default:
1727                 return -ENODEV;
1728         }
1729
1730         return 0;
1731 }
1732
1733 bool acpi_device_is_present(const struct acpi_device *adev)
1734 {
1735         return adev->status.present || adev->status.functional;
1736 }
1737
1738 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1739                                        const char *idstr,
1740                                        const struct acpi_device_id **matchid)
1741 {
1742         const struct acpi_device_id *devid;
1743
1744         if (handler->match)
1745                 return handler->match(idstr, matchid);
1746
1747         for (devid = handler->ids; devid->id[0]; devid++)
1748                 if (!strcmp((char *)devid->id, idstr)) {
1749                         if (matchid)
1750                                 *matchid = devid;
1751
1752                         return true;
1753                 }
1754
1755         return false;
1756 }
1757
1758 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1759                                         const struct acpi_device_id **matchid)
1760 {
1761         struct acpi_scan_handler *handler;
1762
1763         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1764                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1765                         return handler;
1766
1767         return NULL;
1768 }
1769
1770 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1771 {
1772         if (!!hotplug->enabled == !!val)
1773                 return;
1774
1775         mutex_lock(&acpi_scan_lock);
1776
1777         hotplug->enabled = val;
1778
1779         mutex_unlock(&acpi_scan_lock);
1780 }
1781
1782 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1783 {
1784         struct acpi_hardware_id *hwid;
1785
1786         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1787                 acpi_dock_add(adev);
1788                 return;
1789         }
1790         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1791                 struct acpi_scan_handler *handler;
1792
1793                 handler = acpi_scan_match_handler(hwid->id, NULL);
1794                 if (handler) {
1795                         adev->flags.hotplug_notify = true;
1796                         break;
1797                 }
1798         }
1799 }
1800
1801 static void acpi_device_dep_initialize(struct acpi_device *adev)
1802 {
1803         struct acpi_dep_data *dep;
1804         struct acpi_handle_list dep_devices;
1805         acpi_status status;
1806         int i;
1807
1808         adev->dep_unmet = 0;
1809
1810         if (!acpi_has_method(adev->handle, "_DEP"))
1811                 return;
1812
1813         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1814                                         &dep_devices);
1815         if (ACPI_FAILURE(status)) {
1816                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1817                 return;
1818         }
1819
1820         for (i = 0; i < dep_devices.count; i++) {
1821                 struct acpi_device_info *info;
1822                 int skip;
1823
1824                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1825                 if (ACPI_FAILURE(status)) {
1826                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1827                         continue;
1828                 }
1829
1830                 /*
1831                  * Skip the dependency of Windows System Power
1832                  * Management Controller
1833                  */
1834                 skip = info->valid & ACPI_VALID_HID &&
1835                         !strcmp(info->hardware_id.string, "INT3396");
1836
1837                 kfree(info);
1838
1839                 if (skip)
1840                         continue;
1841
1842                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1843                 if (!dep)
1844                         return;
1845
1846                 dep->master = dep_devices.handles[i];
1847                 dep->slave  = adev->handle;
1848                 adev->dep_unmet++;
1849
1850                 mutex_lock(&acpi_dep_list_lock);
1851                 list_add_tail(&dep->node , &acpi_dep_list);
1852                 mutex_unlock(&acpi_dep_list_lock);
1853         }
1854 }
1855
1856 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1857                                       void *not_used, void **return_value)
1858 {
1859         struct acpi_device *device = NULL;
1860         int type;
1861         unsigned long long sta;
1862         int result;
1863
1864         acpi_bus_get_device(handle, &device);
1865         if (device)
1866                 goto out;
1867
1868         result = acpi_bus_type_and_status(handle, &type, &sta);
1869         if (result)
1870                 return AE_OK;
1871
1872         if (type == ACPI_BUS_TYPE_POWER) {
1873                 acpi_add_power_resource(handle);
1874                 return AE_OK;
1875         }
1876
1877         acpi_add_single_object(&device, handle, type, sta);
1878         if (!device)
1879                 return AE_CTRL_DEPTH;
1880
1881         acpi_scan_init_hotplug(device);
1882         acpi_device_dep_initialize(device);
1883
1884  out:
1885         if (!*return_value)
1886                 *return_value = device;
1887
1888         return AE_OK;
1889 }
1890
1891 static void acpi_default_enumeration(struct acpi_device *device)
1892 {
1893         /*
1894          * Do not enumerate devices with enumeration_by_parent flag set as
1895          * they will be enumerated by their respective parents.
1896          */
1897         if (!device->flags.enumeration_by_parent) {
1898                 acpi_create_platform_device(device, NULL);
1899                 acpi_device_set_enumerated(device);
1900         } else {
1901                 blocking_notifier_call_chain(&acpi_reconfig_chain,
1902                                              ACPI_RECONFIG_DEVICE_ADD, device);
1903         }
1904 }
1905
1906 static const struct acpi_device_id generic_device_ids[] = {
1907         {ACPI_DT_NAMESPACE_HID, },
1908         {"", },
1909 };
1910
1911 static int acpi_generic_device_attach(struct acpi_device *adev,
1912                                       const struct acpi_device_id *not_used)
1913 {
1914         /*
1915          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1916          * below can be unconditional.
1917          */
1918         if (adev->data.of_compatible)
1919                 acpi_default_enumeration(adev);
1920
1921         return 1;
1922 }
1923
1924 static struct acpi_scan_handler generic_device_handler = {
1925         .ids = generic_device_ids,
1926         .attach = acpi_generic_device_attach,
1927 };
1928
1929 static int acpi_scan_attach_handler(struct acpi_device *device)
1930 {
1931         struct acpi_hardware_id *hwid;
1932         int ret = 0;
1933
1934         list_for_each_entry(hwid, &device->pnp.ids, list) {
1935                 const struct acpi_device_id *devid;
1936                 struct acpi_scan_handler *handler;
1937
1938                 handler = acpi_scan_match_handler(hwid->id, &devid);
1939                 if (handler) {
1940                         if (!handler->attach) {
1941                                 device->pnp.type.platform_id = 0;
1942                                 continue;
1943                         }
1944                         device->handler = handler;
1945                         ret = handler->attach(device, devid);
1946                         if (ret > 0)
1947                                 break;
1948
1949                         device->handler = NULL;
1950                         if (ret < 0)
1951                                 break;
1952                 }
1953         }
1954
1955         return ret;
1956 }
1957
1958 static void acpi_bus_attach(struct acpi_device *device)
1959 {
1960         struct acpi_device *child;
1961         acpi_handle ejd;
1962         int ret;
1963
1964         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1965                 register_dock_dependent_device(device, ejd);
1966
1967         acpi_bus_get_status(device);
1968         /* Skip devices that are not present. */
1969         if (!acpi_device_is_present(device)) {
1970                 device->flags.initialized = false;
1971                 acpi_device_clear_enumerated(device);
1972                 device->flags.power_manageable = 0;
1973                 return;
1974         }
1975         if (device->handler)
1976                 goto ok;
1977
1978         if (!device->flags.initialized) {
1979                 device->flags.power_manageable =
1980                         device->power.states[ACPI_STATE_D0].flags.valid;
1981                 if (acpi_bus_init_power(device))
1982                         device->flags.power_manageable = 0;
1983
1984                 device->flags.initialized = true;
1985         } else if (device->flags.visited) {
1986                 goto ok;
1987         }
1988
1989         ret = acpi_scan_attach_handler(device);
1990         if (ret < 0)
1991                 return;
1992
1993         device->flags.match_driver = true;
1994         if (ret > 0 && !device->flags.enumeration_by_parent) {
1995                 acpi_device_set_enumerated(device);
1996                 goto ok;
1997         }
1998
1999         ret = device_attach(&device->dev);
2000         if (ret < 0)
2001                 return;
2002
2003         if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2004                 acpi_default_enumeration(device);
2005         else
2006                 acpi_device_set_enumerated(device);
2007
2008  ok:
2009         list_for_each_entry(child, &device->children, node)
2010                 acpi_bus_attach(child);
2011
2012         if (device->handler && device->handler->hotplug.notify_online)
2013                 device->handler->hotplug.notify_online(device);
2014 }
2015
2016 void acpi_walk_dep_device_list(acpi_handle handle)
2017 {
2018         struct acpi_dep_data *dep, *tmp;
2019         struct acpi_device *adev;
2020
2021         mutex_lock(&acpi_dep_list_lock);
2022         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2023                 if (dep->master == handle) {
2024                         acpi_bus_get_device(dep->slave, &adev);
2025                         if (!adev)
2026                                 continue;
2027
2028                         adev->dep_unmet--;
2029                         if (!adev->dep_unmet)
2030                                 acpi_bus_attach(adev);
2031                         list_del(&dep->node);
2032                         kfree(dep);
2033                 }
2034         }
2035         mutex_unlock(&acpi_dep_list_lock);
2036 }
2037 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2038
2039 /**
2040  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2041  * @handle: Root of the namespace scope to scan.
2042  *
2043  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2044  * found devices.
2045  *
2046  * If no devices were found, -ENODEV is returned, but it does not mean that
2047  * there has been a real error.  There just have been no suitable ACPI objects
2048  * in the table trunk from which the kernel could create a device and add an
2049  * appropriate driver.
2050  *
2051  * Must be called under acpi_scan_lock.
2052  */
2053 int acpi_bus_scan(acpi_handle handle)
2054 {
2055         void *device = NULL;
2056
2057         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2058                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2059                                     acpi_bus_check_add, NULL, NULL, &device);
2060
2061         if (device) {
2062                 acpi_bus_attach(device);
2063                 return 0;
2064         }
2065         return -ENODEV;
2066 }
2067 EXPORT_SYMBOL(acpi_bus_scan);
2068
2069 /**
2070  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2071  * @adev: Root of the ACPI namespace scope to walk.
2072  *
2073  * Must be called under acpi_scan_lock.
2074  */
2075 void acpi_bus_trim(struct acpi_device *adev)
2076 {
2077         struct acpi_scan_handler *handler = adev->handler;
2078         struct acpi_device *child;
2079
2080         list_for_each_entry_reverse(child, &adev->children, node)
2081                 acpi_bus_trim(child);
2082
2083         adev->flags.match_driver = false;
2084         if (handler) {
2085                 if (handler->detach)
2086                         handler->detach(adev);
2087
2088                 adev->handler = NULL;
2089         } else {
2090                 device_release_driver(&adev->dev);
2091         }
2092         /*
2093          * Most likely, the device is going away, so put it into D3cold before
2094          * that.
2095          */
2096         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2097         adev->flags.initialized = false;
2098         acpi_device_clear_enumerated(adev);
2099 }
2100 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2101
2102 int acpi_bus_register_early_device(int type)
2103 {
2104         struct acpi_device *device = NULL;
2105         int result;
2106
2107         result = acpi_add_single_object(&device, NULL,
2108                                         type, ACPI_STA_DEFAULT);
2109         if (result)
2110                 return result;
2111
2112         device->flags.match_driver = true;
2113         return device_attach(&device->dev);
2114 }
2115 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2116
2117 static int acpi_bus_scan_fixed(void)
2118 {
2119         int result = 0;
2120
2121         /*
2122          * Enumerate all fixed-feature devices.
2123          */
2124         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2125                 struct acpi_device *device = NULL;
2126
2127                 result = acpi_add_single_object(&device, NULL,
2128                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2129                                                 ACPI_STA_DEFAULT);
2130                 if (result)
2131                         return result;
2132
2133                 device->flags.match_driver = true;
2134                 result = device_attach(&device->dev);
2135                 if (result < 0)
2136                         return result;
2137
2138                 device_init_wakeup(&device->dev, true);
2139         }
2140
2141         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2142                 struct acpi_device *device = NULL;
2143
2144                 result = acpi_add_single_object(&device, NULL,
2145                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2146                                                 ACPI_STA_DEFAULT);
2147                 if (result)
2148                         return result;
2149
2150                 device->flags.match_driver = true;
2151                 result = device_attach(&device->dev);
2152         }
2153
2154         return result < 0 ? result : 0;
2155 }
2156
2157 static void __init acpi_get_spcr_uart_addr(void)
2158 {
2159         acpi_status status;
2160         struct acpi_table_spcr *spcr_ptr;
2161
2162         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2163                                 (struct acpi_table_header **)&spcr_ptr);
2164         if (ACPI_SUCCESS(status))
2165                 spcr_uart_addr = spcr_ptr->serial_port.address;
2166         else
2167                 printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2168 }
2169
2170 static bool acpi_scan_initialized;
2171
2172 int __init acpi_scan_init(void)
2173 {
2174         int result;
2175         acpi_status status;
2176         struct acpi_table_stao *stao_ptr;
2177
2178         acpi_pci_root_init();
2179         acpi_pci_link_init();
2180         acpi_processor_init();
2181         acpi_lpss_init();
2182         acpi_apd_init();
2183         acpi_cmos_rtc_init();
2184         acpi_container_init();
2185         acpi_memory_hotplug_init();
2186         acpi_watchdog_init();
2187         acpi_pnp_init();
2188         acpi_int340x_thermal_init();
2189         acpi_amba_init();
2190         acpi_init_lpit();
2191
2192         acpi_scan_add_handler(&generic_device_handler);
2193
2194         /*
2195          * If there is STAO table, check whether it needs to ignore the UART
2196          * device in SPCR table.
2197          */
2198         status = acpi_get_table(ACPI_SIG_STAO, 0,
2199                                 (struct acpi_table_header **)&stao_ptr);
2200         if (ACPI_SUCCESS(status)) {
2201                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2202                         printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2203
2204                 if (stao_ptr->ignore_uart)
2205                         acpi_get_spcr_uart_addr();
2206         }
2207
2208         acpi_gpe_apply_masked_gpes();
2209         acpi_update_all_gpes();
2210
2211         mutex_lock(&acpi_scan_lock);
2212         /*
2213          * Enumerate devices in the ACPI namespace.
2214          */
2215         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2216         if (result)
2217                 goto out;
2218
2219         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2220         if (result)
2221                 goto out;
2222
2223         /* Fixed feature devices do not exist on HW-reduced platform */
2224         if (!acpi_gbl_reduced_hardware) {
2225                 result = acpi_bus_scan_fixed();
2226                 if (result) {
2227                         acpi_detach_data(acpi_root->handle,
2228                                          acpi_scan_drop_device);
2229                         acpi_device_del(acpi_root);
2230                         put_device(&acpi_root->dev);
2231                         goto out;
2232                 }
2233         }
2234
2235         acpi_scan_initialized = true;
2236
2237  out:
2238         mutex_unlock(&acpi_scan_lock);
2239         return result;
2240 }
2241
2242 static struct acpi_probe_entry *ape;
2243 static int acpi_probe_count;
2244 static DEFINE_MUTEX(acpi_probe_mutex);
2245
2246 static int __init acpi_match_madt(struct acpi_subtable_header *header,
2247                                   const unsigned long end)
2248 {
2249         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2250                 if (!ape->probe_subtbl(header, end))
2251                         acpi_probe_count++;
2252
2253         return 0;
2254 }
2255
2256 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2257 {
2258         int count = 0;
2259
2260         if (acpi_disabled)
2261                 return 0;
2262
2263         mutex_lock(&acpi_probe_mutex);
2264         for (ape = ap_head; nr; ape++, nr--) {
2265                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2266                         acpi_probe_count = 0;
2267                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2268                         count += acpi_probe_count;
2269                 } else {
2270                         int res;
2271                         res = acpi_table_parse(ape->id, ape->probe_table);
2272                         if (!res)
2273                                 count++;
2274                 }
2275         }
2276         mutex_unlock(&acpi_probe_mutex);
2277
2278         return count;
2279 }
2280
2281 struct acpi_table_events_work {
2282         struct work_struct work;
2283         void *table;
2284         u32 event;
2285 };
2286
2287 static void acpi_table_events_fn(struct work_struct *work)
2288 {
2289         struct acpi_table_events_work *tew;
2290
2291         tew = container_of(work, struct acpi_table_events_work, work);
2292
2293         if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2294                 acpi_scan_lock_acquire();
2295                 acpi_bus_scan(ACPI_ROOT_OBJECT);
2296                 acpi_scan_lock_release();
2297         }
2298
2299         kfree(tew);
2300 }
2301
2302 void acpi_scan_table_handler(u32 event, void *table, void *context)
2303 {
2304         struct acpi_table_events_work *tew;
2305
2306         if (!acpi_scan_initialized)
2307                 return;
2308
2309         if (event != ACPI_TABLE_EVENT_LOAD)
2310                 return;
2311
2312         tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2313         if (!tew)
2314                 return;
2315
2316         INIT_WORK(&tew->work, acpi_table_events_fn);
2317         tew->table = table;
2318         tew->event = event;
2319
2320         schedule_work(&tew->work);
2321 }
2322
2323 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2324 {
2325         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2326 }
2327 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2328
2329 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2330 {
2331         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2332 }
2333 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);