Version:  2.0.40 2.2.26 2.4.37 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4

Linux/drivers/acpi/scan.c

  1 /*
  2  * scan.c - support for transforming the ACPI namespace into individual objects
  3  */
  4 
  5 #include <linux/module.h>
  6 #include <linux/init.h>
  7 #include <linux/slab.h>
  8 #include <linux/kernel.h>
  9 #include <linux/acpi.h>
 10 #include <linux/signal.h>
 11 #include <linux/kthread.h>
 12 #include <linux/dmi.h>
 13 #include <linux/nls.h>
 14 #include <linux/dma-mapping.h>
 15 
 16 #include <asm/pgtable.h>
 17 
 18 #include "internal.h"
 19 
 20 #define _COMPONENT              ACPI_BUS_COMPONENT
 21 ACPI_MODULE_NAME("scan");
 22 extern struct acpi_device *acpi_root;
 23 
 24 #define ACPI_BUS_CLASS                  "system_bus"
 25 #define ACPI_BUS_HID                    "LNXSYBUS"
 26 #define ACPI_BUS_DEVICE_NAME            "System Bus"
 27 
 28 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
 29 
 30 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
 31 
 32 /*
 33  * If set, devices will be hot-removed even if they cannot be put offline
 34  * gracefully (from the kernel's standpoint).
 35  */
 36 bool acpi_force_hot_remove;
 37 
 38 static const char *dummy_hid = "device";
 39 
 40 static LIST_HEAD(acpi_dep_list);
 41 static DEFINE_MUTEX(acpi_dep_list_lock);
 42 static LIST_HEAD(acpi_bus_id_list);
 43 static DEFINE_MUTEX(acpi_scan_lock);
 44 static LIST_HEAD(acpi_scan_handlers_list);
 45 DEFINE_MUTEX(acpi_device_lock);
 46 LIST_HEAD(acpi_wakeup_device_list);
 47 static DEFINE_MUTEX(acpi_hp_context_lock);
 48 
 49 struct acpi_dep_data {
 50         struct list_head node;
 51         acpi_handle master;
 52         acpi_handle slave;
 53 };
 54 
 55 struct acpi_device_bus_id{
 56         char bus_id[15];
 57         unsigned int instance_no;
 58         struct list_head node;
 59 };
 60 
 61 void acpi_scan_lock_acquire(void)
 62 {
 63         mutex_lock(&acpi_scan_lock);
 64 }
 65 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
 66 
 67 void acpi_scan_lock_release(void)
 68 {
 69         mutex_unlock(&acpi_scan_lock);
 70 }
 71 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
 72 
 73 void acpi_lock_hp_context(void)
 74 {
 75         mutex_lock(&acpi_hp_context_lock);
 76 }
 77 
 78 void acpi_unlock_hp_context(void)
 79 {
 80         mutex_unlock(&acpi_hp_context_lock);
 81 }
 82 
 83 void acpi_initialize_hp_context(struct acpi_device *adev,
 84                                 struct acpi_hotplug_context *hp,
 85                                 int (*notify)(struct acpi_device *, u32),
 86                                 void (*uevent)(struct acpi_device *, u32))
 87 {
 88         acpi_lock_hp_context();
 89         hp->notify = notify;
 90         hp->uevent = uevent;
 91         acpi_set_hp_context(adev, hp);
 92         acpi_unlock_hp_context();
 93 }
 94 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
 95 
 96 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
 97 {
 98         if (!handler)
 99                 return -EINVAL;
100 
101         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
102         return 0;
103 }
104 
105 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
106                                        const char *hotplug_profile_name)
107 {
108         int error;
109 
110         error = acpi_scan_add_handler(handler);
111         if (error)
112                 return error;
113 
114         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
115         return 0;
116 }
117 
118 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
119 {
120         struct acpi_device_physical_node *pn;
121         bool offline = true;
122 
123         /*
124          * acpi_container_offline() calls this for all of the container's
125          * children under the container's physical_node_lock lock.
126          */
127         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
128 
129         list_for_each_entry(pn, &adev->physical_node_list, node)
130                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
131                         if (uevent)
132                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
133 
134                         offline = false;
135                         break;
136                 }
137 
138         mutex_unlock(&adev->physical_node_lock);
139         return offline;
140 }
141 
142 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
143                                     void **ret_p)
144 {
145         struct acpi_device *device = NULL;
146         struct acpi_device_physical_node *pn;
147         bool second_pass = (bool)data;
148         acpi_status status = AE_OK;
149 
150         if (acpi_bus_get_device(handle, &device))
151                 return AE_OK;
152 
153         if (device->handler && !device->handler->hotplug.enabled) {
154                 *ret_p = &device->dev;
155                 return AE_SUPPORT;
156         }
157 
158         mutex_lock(&device->physical_node_lock);
159 
160         list_for_each_entry(pn, &device->physical_node_list, node) {
161                 int ret;
162 
163                 if (second_pass) {
164                         /* Skip devices offlined by the first pass. */
165                         if (pn->put_online)
166                                 continue;
167                 } else {
168                         pn->put_online = false;
169                 }
170                 ret = device_offline(pn->dev);
171                 if (acpi_force_hot_remove)
172                         continue;
173 
174                 if (ret >= 0) {
175                         pn->put_online = !ret;
176                 } else {
177                         *ret_p = pn->dev;
178                         if (second_pass) {
179                                 status = AE_ERROR;
180                                 break;
181                         }
182                 }
183         }
184 
185         mutex_unlock(&device->physical_node_lock);
186 
187         return status;
188 }
189 
190 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
191                                    void **ret_p)
192 {
193         struct acpi_device *device = NULL;
194         struct acpi_device_physical_node *pn;
195 
196         if (acpi_bus_get_device(handle, &device))
197                 return AE_OK;
198 
199         mutex_lock(&device->physical_node_lock);
200 
201         list_for_each_entry(pn, &device->physical_node_list, node)
202                 if (pn->put_online) {
203                         device_online(pn->dev);
204                         pn->put_online = false;
205                 }
206 
207         mutex_unlock(&device->physical_node_lock);
208 
209         return AE_OK;
210 }
211 
212 static int acpi_scan_try_to_offline(struct acpi_device *device)
213 {
214         acpi_handle handle = device->handle;
215         struct device *errdev = NULL;
216         acpi_status status;
217 
218         /*
219          * Carry out two passes here and ignore errors in the first pass,
220          * because if the devices in question are memory blocks and
221          * CONFIG_MEMCG is set, one of the blocks may hold data structures
222          * that the other blocks depend on, but it is not known in advance which
223          * block holds them.
224          *
225          * If the first pass is successful, the second one isn't needed, though.
226          */
227         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
228                                      NULL, acpi_bus_offline, (void *)false,
229                                      (void **)&errdev);
230         if (status == AE_SUPPORT) {
231                 dev_warn(errdev, "Offline disabled.\n");
232                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
233                                     acpi_bus_online, NULL, NULL, NULL);
234                 return -EPERM;
235         }
236         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
237         if (errdev) {
238                 errdev = NULL;
239                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
240                                     NULL, acpi_bus_offline, (void *)true,
241                                     (void **)&errdev);
242                 if (!errdev || acpi_force_hot_remove)
243                         acpi_bus_offline(handle, 0, (void *)true,
244                                          (void **)&errdev);
245 
246                 if (errdev && !acpi_force_hot_remove) {
247                         dev_warn(errdev, "Offline failed.\n");
248                         acpi_bus_online(handle, 0, NULL, NULL);
249                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
250                                             ACPI_UINT32_MAX, acpi_bus_online,
251                                             NULL, NULL, NULL);
252                         return -EBUSY;
253                 }
254         }
255         return 0;
256 }
257 
258 static int acpi_scan_hot_remove(struct acpi_device *device)
259 {
260         acpi_handle handle = device->handle;
261         unsigned long long sta;
262         acpi_status status;
263 
264         if (device->handler && device->handler->hotplug.demand_offline
265             && !acpi_force_hot_remove) {
266                 if (!acpi_scan_is_offline(device, true))
267                         return -EBUSY;
268         } else {
269                 int error = acpi_scan_try_to_offline(device);
270                 if (error)
271                         return error;
272         }
273 
274         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
275                 "Hot-removing device %s...\n", dev_name(&device->dev)));
276 
277         acpi_bus_trim(device);
278 
279         acpi_evaluate_lck(handle, 0);
280         /*
281          * TBD: _EJD support.
282          */
283         status = acpi_evaluate_ej0(handle);
284         if (status == AE_NOT_FOUND)
285                 return -ENODEV;
286         else if (ACPI_FAILURE(status))
287                 return -EIO;
288 
289         /*
290          * Verify if eject was indeed successful.  If not, log an error
291          * message.  No need to call _OST since _EJ0 call was made OK.
292          */
293         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
294         if (ACPI_FAILURE(status)) {
295                 acpi_handle_warn(handle,
296                         "Status check after eject failed (0x%x)\n", status);
297         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
298                 acpi_handle_warn(handle,
299                         "Eject incomplete - status 0x%llx\n", sta);
300         }
301 
302         return 0;
303 }
304 
305 static int acpi_scan_device_not_present(struct acpi_device *adev)
306 {
307         if (!acpi_device_enumerated(adev)) {
308                 dev_warn(&adev->dev, "Still not present\n");
309                 return -EALREADY;
310         }
311         acpi_bus_trim(adev);
312         return 0;
313 }
314 
315 static int acpi_scan_device_check(struct acpi_device *adev)
316 {
317         int error;
318 
319         acpi_bus_get_status(adev);
320         if (adev->status.present || adev->status.functional) {
321                 /*
322                  * This function is only called for device objects for which
323                  * matching scan handlers exist.  The only situation in which
324                  * the scan handler is not attached to this device object yet
325                  * is when the device has just appeared (either it wasn't
326                  * present at all before or it was removed and then added
327                  * again).
328                  */
329                 if (adev->handler) {
330                         dev_warn(&adev->dev, "Already enumerated\n");
331                         return -EALREADY;
332                 }
333                 error = acpi_bus_scan(adev->handle);
334                 if (error) {
335                         dev_warn(&adev->dev, "Namespace scan failure\n");
336                         return error;
337                 }
338                 if (!adev->handler) {
339                         dev_warn(&adev->dev, "Enumeration failure\n");
340                         error = -ENODEV;
341                 }
342         } else {
343                 error = acpi_scan_device_not_present(adev);
344         }
345         return error;
346 }
347 
348 static int acpi_scan_bus_check(struct acpi_device *adev)
349 {
350         struct acpi_scan_handler *handler = adev->handler;
351         struct acpi_device *child;
352         int error;
353 
354         acpi_bus_get_status(adev);
355         if (!(adev->status.present || adev->status.functional)) {
356                 acpi_scan_device_not_present(adev);
357                 return 0;
358         }
359         if (handler && handler->hotplug.scan_dependent)
360                 return handler->hotplug.scan_dependent(adev);
361 
362         error = acpi_bus_scan(adev->handle);
363         if (error) {
364                 dev_warn(&adev->dev, "Namespace scan failure\n");
365                 return error;
366         }
367         list_for_each_entry(child, &adev->children, node) {
368                 error = acpi_scan_bus_check(child);
369                 if (error)
370                         return error;
371         }
372         return 0;
373 }
374 
375 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
376 {
377         switch (type) {
378         case ACPI_NOTIFY_BUS_CHECK:
379                 return acpi_scan_bus_check(adev);
380         case ACPI_NOTIFY_DEVICE_CHECK:
381                 return acpi_scan_device_check(adev);
382         case ACPI_NOTIFY_EJECT_REQUEST:
383         case ACPI_OST_EC_OSPM_EJECT:
384                 if (adev->handler && !adev->handler->hotplug.enabled) {
385                         dev_info(&adev->dev, "Eject disabled\n");
386                         return -EPERM;
387                 }
388                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
389                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
390                 return acpi_scan_hot_remove(adev);
391         }
392         return -EINVAL;
393 }
394 
395 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
396 {
397         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
398         int error = -ENODEV;
399 
400         lock_device_hotplug();
401         mutex_lock(&acpi_scan_lock);
402 
403         /*
404          * The device object's ACPI handle cannot become invalid as long as we
405          * are holding acpi_scan_lock, but it might have become invalid before
406          * that lock was acquired.
407          */
408         if (adev->handle == INVALID_ACPI_HANDLE)
409                 goto err_out;
410 
411         if (adev->flags.is_dock_station) {
412                 error = dock_notify(adev, src);
413         } else if (adev->flags.hotplug_notify) {
414                 error = acpi_generic_hotplug_event(adev, src);
415                 if (error == -EPERM) {
416                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
417                         goto err_out;
418                 }
419         } else {
420                 int (*notify)(struct acpi_device *, u32);
421 
422                 acpi_lock_hp_context();
423                 notify = adev->hp ? adev->hp->notify : NULL;
424                 acpi_unlock_hp_context();
425                 /*
426                  * There may be additional notify handlers for device objects
427                  * without the .event() callback, so ignore them here.
428                  */
429                 if (notify)
430                         error = notify(adev, src);
431                 else
432                         goto out;
433         }
434         if (!error)
435                 ost_code = ACPI_OST_SC_SUCCESS;
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         mutex_lock(&acpi_device_lock);
475         if (device->parent)
476                 list_del(&device->node);
477 
478         list_del(&device->wakeup_list);
479         mutex_unlock(&acpi_device_lock);
480 
481         acpi_power_add_remove_device(device, false);
482         acpi_device_remove_files(device);
483         if (device->remove)
484                 device->remove(device);
485 
486         device_del(&device->dev);
487 }
488 
489 static LIST_HEAD(acpi_device_del_list);
490 static DEFINE_MUTEX(acpi_device_del_lock);
491 
492 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
493 {
494         for (;;) {
495                 struct acpi_device *adev;
496 
497                 mutex_lock(&acpi_device_del_lock);
498 
499                 if (list_empty(&acpi_device_del_list)) {
500                         mutex_unlock(&acpi_device_del_lock);
501                         break;
502                 }
503                 adev = list_first_entry(&acpi_device_del_list,
504                                         struct acpi_device, del_list);
505                 list_del(&adev->del_list);
506 
507                 mutex_unlock(&acpi_device_del_lock);
508 
509                 acpi_device_del(adev);
510                 /*
511                  * Drop references to all power resources that might have been
512                  * used by the device.
513                  */
514                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
515                 put_device(&adev->dev);
516         }
517 }
518 
519 /**
520  * acpi_scan_drop_device - Drop an ACPI device object.
521  * @handle: Handle of an ACPI namespace node, not used.
522  * @context: Address of the ACPI device object to drop.
523  *
524  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
525  * namespace node the device object pointed to by @context is attached to.
526  *
527  * The unregistration is carried out asynchronously to avoid running
528  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
529  * ensure the correct ordering (the device objects must be unregistered in the
530  * same order in which the corresponding namespace nodes are deleted).
531  */
532 static void acpi_scan_drop_device(acpi_handle handle, void *context)
533 {
534         static DECLARE_WORK(work, acpi_device_del_work_fn);
535         struct acpi_device *adev = context;
536 
537         mutex_lock(&acpi_device_del_lock);
538 
539         /*
540          * Use the ACPI hotplug workqueue which is ordered, so this work item
541          * won't run after any hotplug work items submitted subsequently.  That
542          * prevents attempts to register device objects identical to those being
543          * deleted from happening concurrently (such attempts result from
544          * hotplug events handled via the ACPI hotplug workqueue).  It also will
545          * run after all of the work items submitted previosuly, which helps
546          * those work items to ensure that they are not accessing stale device
547          * objects.
548          */
549         if (list_empty(&acpi_device_del_list))
550                 acpi_queue_hotplug_work(&work);
551 
552         list_add_tail(&adev->del_list, &acpi_device_del_list);
553         /* Make acpi_ns_validate_handle() return NULL for this handle. */
554         adev->handle = INVALID_ACPI_HANDLE;
555 
556         mutex_unlock(&acpi_device_del_lock);
557 }
558 
559 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
560                                 void (*callback)(void *))
561 {
562         acpi_status status;
563 
564         if (!device)
565                 return -EINVAL;
566 
567         status = acpi_get_data_full(handle, acpi_scan_drop_device,
568                                     (void **)device, callback);
569         if (ACPI_FAILURE(status) || !*device) {
570                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
571                                   handle));
572                 return -ENODEV;
573         }
574         return 0;
575 }
576 
577 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
578 {
579         return acpi_get_device_data(handle, device, NULL);
580 }
581 EXPORT_SYMBOL(acpi_bus_get_device);
582 
583 static void get_acpi_device(void *dev)
584 {
585         if (dev)
586                 get_device(&((struct acpi_device *)dev)->dev);
587 }
588 
589 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
590 {
591         struct acpi_device *adev = NULL;
592 
593         acpi_get_device_data(handle, &adev, get_acpi_device);
594         return adev;
595 }
596 
597 void acpi_bus_put_acpi_device(struct acpi_device *adev)
598 {
599         put_device(&adev->dev);
600 }
601 
602 int acpi_device_add(struct acpi_device *device,
603                     void (*release)(struct device *))
604 {
605         int result;
606         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
607         int found = 0;
608 
609         if (device->handle) {
610                 acpi_status status;
611 
612                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
613                                           device);
614                 if (ACPI_FAILURE(status)) {
615                         acpi_handle_err(device->handle,
616                                         "Unable to attach device data\n");
617                         return -ENODEV;
618                 }
619         }
620 
621         /*
622          * Linkage
623          * -------
624          * Link this device to its parent and siblings.
625          */
626         INIT_LIST_HEAD(&device->children);
627         INIT_LIST_HEAD(&device->node);
628         INIT_LIST_HEAD(&device->wakeup_list);
629         INIT_LIST_HEAD(&device->physical_node_list);
630         INIT_LIST_HEAD(&device->del_list);
631         mutex_init(&device->physical_node_lock);
632 
633         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
634         if (!new_bus_id) {
635                 pr_err(PREFIX "Memory allocation error\n");
636                 result = -ENOMEM;
637                 goto err_detach;
638         }
639 
640         mutex_lock(&acpi_device_lock);
641         /*
642          * Find suitable bus_id and instance number in acpi_bus_id_list
643          * If failed, create one and link it into acpi_bus_id_list
644          */
645         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
646                 if (!strcmp(acpi_device_bus_id->bus_id,
647                             acpi_device_hid(device))) {
648                         acpi_device_bus_id->instance_no++;
649                         found = 1;
650                         kfree(new_bus_id);
651                         break;
652                 }
653         }
654         if (!found) {
655                 acpi_device_bus_id = new_bus_id;
656                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
657                 acpi_device_bus_id->instance_no = 0;
658                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
659         }
660         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
661 
662         if (device->parent)
663                 list_add_tail(&device->node, &device->parent->children);
664 
665         if (device->wakeup.flags.valid)
666                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
667         mutex_unlock(&acpi_device_lock);
668 
669         if (device->parent)
670                 device->dev.parent = &device->parent->dev;
671         device->dev.bus = &acpi_bus_type;
672         device->dev.release = release;
673         result = device_add(&device->dev);
674         if (result) {
675                 dev_err(&device->dev, "Error registering device\n");
676                 goto err;
677         }
678 
679         result = acpi_device_setup_files(device);
680         if (result)
681                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
682                        dev_name(&device->dev));
683 
684         return 0;
685 
686  err:
687         mutex_lock(&acpi_device_lock);
688         if (device->parent)
689                 list_del(&device->node);
690         list_del(&device->wakeup_list);
691         mutex_unlock(&acpi_device_lock);
692 
693  err_detach:
694         acpi_detach_data(device->handle, acpi_scan_drop_device);
695         return result;
696 }
697 
698 /* --------------------------------------------------------------------------
699                                  Device Enumeration
700    -------------------------------------------------------------------------- */
701 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
702 {
703         struct acpi_device *device = NULL;
704         acpi_status status;
705 
706         /*
707          * Fixed hardware devices do not appear in the namespace and do not
708          * have handles, but we fabricate acpi_devices for them, so we have
709          * to deal with them specially.
710          */
711         if (!handle)
712                 return acpi_root;
713 
714         do {
715                 status = acpi_get_parent(handle, &handle);
716                 if (ACPI_FAILURE(status))
717                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
718         } while (acpi_bus_get_device(handle, &device));
719         return device;
720 }
721 
722 acpi_status
723 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
724 {
725         acpi_status status;
726         acpi_handle tmp;
727         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
728         union acpi_object *obj;
729 
730         status = acpi_get_handle(handle, "_EJD", &tmp);
731         if (ACPI_FAILURE(status))
732                 return status;
733 
734         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
735         if (ACPI_SUCCESS(status)) {
736                 obj = buffer.pointer;
737                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
738                                          ejd);
739                 kfree(buffer.pointer);
740         }
741         return status;
742 }
743 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
744 
745 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
746                                         struct acpi_device_wakeup *wakeup)
747 {
748         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
749         union acpi_object *package = NULL;
750         union acpi_object *element = NULL;
751         acpi_status status;
752         int err = -ENODATA;
753 
754         if (!wakeup)
755                 return -EINVAL;
756 
757         INIT_LIST_HEAD(&wakeup->resources);
758 
759         /* _PRW */
760         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
761         if (ACPI_FAILURE(status)) {
762                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
763                 return err;
764         }
765 
766         package = (union acpi_object *)buffer.pointer;
767 
768         if (!package || package->package.count < 2)
769                 goto out;
770 
771         element = &(package->package.elements[0]);
772         if (!element)
773                 goto out;
774 
775         if (element->type == ACPI_TYPE_PACKAGE) {
776                 if ((element->package.count < 2) ||
777                     (element->package.elements[0].type !=
778                      ACPI_TYPE_LOCAL_REFERENCE)
779                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
780                         goto out;
781 
782                 wakeup->gpe_device =
783                     element->package.elements[0].reference.handle;
784                 wakeup->gpe_number =
785                     (u32) element->package.elements[1].integer.value;
786         } else if (element->type == ACPI_TYPE_INTEGER) {
787                 wakeup->gpe_device = NULL;
788                 wakeup->gpe_number = element->integer.value;
789         } else {
790                 goto out;
791         }
792 
793         element = &(package->package.elements[1]);
794         if (element->type != ACPI_TYPE_INTEGER)
795                 goto out;
796 
797         wakeup->sleep_state = element->integer.value;
798 
799         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
800         if (err)
801                 goto out;
802 
803         if (!list_empty(&wakeup->resources)) {
804                 int sleep_state;
805 
806                 err = acpi_power_wakeup_list_init(&wakeup->resources,
807                                                   &sleep_state);
808                 if (err) {
809                         acpi_handle_warn(handle, "Retrieving current states "
810                                          "of wakeup power resources failed\n");
811                         acpi_power_resources_list_free(&wakeup->resources);
812                         goto out;
813                 }
814                 if (sleep_state < wakeup->sleep_state) {
815                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
816                                          "(S%d) by S%d from power resources\n",
817                                          (int)wakeup->sleep_state, sleep_state);
818                         wakeup->sleep_state = sleep_state;
819                 }
820         }
821 
822  out:
823         kfree(buffer.pointer);
824         return err;
825 }
826 
827 static void acpi_wakeup_gpe_init(struct acpi_device *device)
828 {
829         static const struct acpi_device_id button_device_ids[] = {
830                 {"PNP0C0C", 0},
831                 {"PNP0C0D", 0},
832                 {"PNP0C0E", 0},
833                 {"", 0},
834         };
835         struct acpi_device_wakeup *wakeup = &device->wakeup;
836         acpi_status status;
837         acpi_event_status event_status;
838 
839         wakeup->flags.notifier_present = 0;
840 
841         /* Power button, Lid switch always enable wakeup */
842         if (!acpi_match_device_ids(device, button_device_ids)) {
843                 wakeup->flags.run_wake = 1;
844                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
845                         /* Do not use Lid/sleep button for S5 wakeup */
846                         if (wakeup->sleep_state == ACPI_STATE_S5)
847                                 wakeup->sleep_state = ACPI_STATE_S4;
848                 }
849                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
850                 device_set_wakeup_capable(&device->dev, true);
851                 return;
852         }
853 
854         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
855                                 wakeup->gpe_number);
856         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
857                                      &event_status);
858         if (ACPI_FAILURE(status))
859                 return;
860 
861         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
862 }
863 
864 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
865 {
866         int err;
867 
868         /* Presence of _PRW indicates wake capable */
869         if (!acpi_has_method(device->handle, "_PRW"))
870                 return;
871 
872         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
873                                                            &device->wakeup);
874         if (err) {
875                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
876                 return;
877         }
878 
879         device->wakeup.flags.valid = 1;
880         device->wakeup.prepare_count = 0;
881         acpi_wakeup_gpe_init(device);
882         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
883          * system for the ACPI device with the _PRW object.
884          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
885          * So it is necessary to call _DSW object first. Only when it is not
886          * present will the _PSW object used.
887          */
888         err = acpi_device_sleep_wake(device, 0, 0, 0);
889         if (err)
890                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
891                                 "error in _DSW or _PSW evaluation\n"));
892 }
893 
894 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
895 {
896         struct acpi_device_power_state *ps = &device->power.states[state];
897         char pathname[5] = { '_', 'P', 'R', '' + state, '\0' };
898         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
899         acpi_status status;
900 
901         INIT_LIST_HEAD(&ps->resources);
902 
903         /* Evaluate "_PRx" to get referenced power resources */
904         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
905         if (ACPI_SUCCESS(status)) {
906                 union acpi_object *package = buffer.pointer;
907 
908                 if (buffer.length && package
909                     && package->type == ACPI_TYPE_PACKAGE
910                     && package->package.count) {
911                         int err = acpi_extract_power_resources(package, 0,
912                                                                &ps->resources);
913                         if (!err)
914                                 device->power.flags.power_resources = 1;
915                 }
916                 ACPI_FREE(buffer.pointer);
917         }
918 
919         /* Evaluate "_PSx" to see if we can do explicit sets */
920         pathname[2] = 'S';
921         if (acpi_has_method(device->handle, pathname))
922                 ps->flags.explicit_set = 1;
923 
924         /* State is valid if there are means to put the device into it. */
925         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
926                 ps->flags.valid = 1;
927 
928         ps->power = -1;         /* Unknown - driver assigned */
929         ps->latency = -1;       /* Unknown - driver assigned */
930 }
931 
932 static void acpi_bus_get_power_flags(struct acpi_device *device)
933 {
934         u32 i;
935 
936         /* Presence of _PS0|_PR0 indicates 'power manageable' */
937         if (!acpi_has_method(device->handle, "_PS0") &&
938             !acpi_has_method(device->handle, "_PR0"))
939                 return;
940 
941         device->flags.power_manageable = 1;
942 
943         /*
944          * Power Management Flags
945          */
946         if (acpi_has_method(device->handle, "_PSC"))
947                 device->power.flags.explicit_get = 1;
948 
949         if (acpi_has_method(device->handle, "_IRC"))
950                 device->power.flags.inrush_current = 1;
951 
952         if (acpi_has_method(device->handle, "_DSW"))
953                 device->power.flags.dsw_present = 1;
954 
955         /*
956          * Enumerate supported power management states
957          */
958         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
959                 acpi_bus_init_power_state(device, i);
960 
961         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
962         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
963                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
964 
965         /* Set defaults for D0 and D3hot states (always valid) */
966         device->power.states[ACPI_STATE_D0].flags.valid = 1;
967         device->power.states[ACPI_STATE_D0].power = 100;
968         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
969 
970         if (acpi_bus_init_power(device))
971                 device->flags.power_manageable = 0;
972 }
973 
974 static void acpi_bus_get_flags(struct acpi_device *device)
975 {
976         /* Presence of _STA indicates 'dynamic_status' */
977         if (acpi_has_method(device->handle, "_STA"))
978                 device->flags.dynamic_status = 1;
979 
980         /* Presence of _RMV indicates 'removable' */
981         if (acpi_has_method(device->handle, "_RMV"))
982                 device->flags.removable = 1;
983 
984         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
985         if (acpi_has_method(device->handle, "_EJD") ||
986             acpi_has_method(device->handle, "_EJ0"))
987                 device->flags.ejectable = 1;
988 }
989 
990 static void acpi_device_get_busid(struct acpi_device *device)
991 {
992         char bus_id[5] = { '?', 0 };
993         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
994         int i = 0;
995 
996         /*
997          * Bus ID
998          * ------
999          * The device's Bus ID is simply the object name.
1000          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1001          */
1002         if (ACPI_IS_ROOT_DEVICE(device)) {
1003                 strcpy(device->pnp.bus_id, "ACPI");
1004                 return;
1005         }
1006 
1007         switch (device->device_type) {
1008         case ACPI_BUS_TYPE_POWER_BUTTON:
1009                 strcpy(device->pnp.bus_id, "PWRF");
1010                 break;
1011         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1012                 strcpy(device->pnp.bus_id, "SLPF");
1013                 break;
1014         default:
1015                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1016                 /* Clean up trailing underscores (if any) */
1017                 for (i = 3; i > 1; i--) {
1018                         if (bus_id[i] == '_')
1019                                 bus_id[i] = '\0';
1020                         else
1021                                 break;
1022                 }
1023                 strcpy(device->pnp.bus_id, bus_id);
1024                 break;
1025         }
1026 }
1027 
1028 /*
1029  * acpi_ata_match - see if an acpi object is an ATA device
1030  *
1031  * If an acpi object has one of the ACPI ATA methods defined,
1032  * then we can safely call it an ATA device.
1033  */
1034 bool acpi_ata_match(acpi_handle handle)
1035 {
1036         return acpi_has_method(handle, "_GTF") ||
1037                acpi_has_method(handle, "_GTM") ||
1038                acpi_has_method(handle, "_STM") ||
1039                acpi_has_method(handle, "_SDD");
1040 }
1041 
1042 /*
1043  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1044  *
1045  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1046  * then we can safely call it an ejectable drive bay
1047  */
1048 bool acpi_bay_match(acpi_handle handle)
1049 {
1050         acpi_handle phandle;
1051 
1052         if (!acpi_has_method(handle, "_EJ0"))
1053                 return false;
1054         if (acpi_ata_match(handle))
1055                 return true;
1056         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1057                 return false;
1058 
1059         return acpi_ata_match(phandle);
1060 }
1061 
1062 bool acpi_device_is_battery(struct acpi_device *adev)
1063 {
1064         struct acpi_hardware_id *hwid;
1065 
1066         list_for_each_entry(hwid, &adev->pnp.ids, list)
1067                 if (!strcmp("PNP0C0A", hwid->id))
1068                         return true;
1069 
1070         return false;
1071 }
1072 
1073 static bool is_ejectable_bay(struct acpi_device *adev)
1074 {
1075         acpi_handle handle = adev->handle;
1076 
1077         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1078                 return true;
1079 
1080         return acpi_bay_match(handle);
1081 }
1082 
1083 /*
1084  * acpi_dock_match - see if an acpi object has a _DCK method
1085  */
1086 bool acpi_dock_match(acpi_handle handle)
1087 {
1088         return acpi_has_method(handle, "_DCK");
1089 }
1090 
1091 static acpi_status
1092 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1093                           void **return_value)
1094 {
1095         long *cap = context;
1096 
1097         if (acpi_has_method(handle, "_BCM") &&
1098             acpi_has_method(handle, "_BCL")) {
1099                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1100                                   "support\n"));
1101                 *cap |= ACPI_VIDEO_BACKLIGHT;
1102                 if (!acpi_has_method(handle, "_BQC"))
1103                         printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
1104                                 "cannot determine initial brightness\n");
1105                 /* We have backlight support, no need to scan further */
1106                 return AE_CTRL_TERMINATE;
1107         }
1108         return 0;
1109 }
1110 
1111 /* Returns true if the ACPI object is a video device which can be
1112  * handled by video.ko.
1113  * The device will get a Linux specific CID added in scan.c to
1114  * identify the device as an ACPI graphics device
1115  * Be aware that the graphics device may not be physically present
1116  * Use acpi_video_get_capabilities() to detect general ACPI video
1117  * capabilities of present cards
1118  */
1119 long acpi_is_video_device(acpi_handle handle)
1120 {
1121         long video_caps = 0;
1122 
1123         /* Is this device able to support video switching ? */
1124         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1125                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1126 
1127         /* Is this device able to retrieve a video ROM ? */
1128         if (acpi_has_method(handle, "_ROM"))
1129                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1130 
1131         /* Is this device able to configure which video head to be POSTed ? */
1132         if (acpi_has_method(handle, "_VPO") &&
1133             acpi_has_method(handle, "_GPD") &&
1134             acpi_has_method(handle, "_SPD"))
1135                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1136 
1137         /* Only check for backlight functionality if one of the above hit. */
1138         if (video_caps)
1139                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1140                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1141                                     &video_caps, NULL);
1142 
1143         return video_caps;
1144 }
1145 EXPORT_SYMBOL(acpi_is_video_device);
1146 
1147 const char *acpi_device_hid(struct acpi_device *device)
1148 {
1149         struct acpi_hardware_id *hid;
1150 
1151         if (list_empty(&device->pnp.ids))
1152                 return dummy_hid;
1153 
1154         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1155         return hid->id;
1156 }
1157 EXPORT_SYMBOL(acpi_device_hid);
1158 
1159 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1160 {
1161         struct acpi_hardware_id *id;
1162 
1163         id = kmalloc(sizeof(*id), GFP_KERNEL);
1164         if (!id)
1165                 return;
1166 
1167         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1168         if (!id->id) {
1169                 kfree(id);
1170                 return;
1171         }
1172 
1173         list_add_tail(&id->list, &pnp->ids);
1174         pnp->type.hardware_id = 1;
1175 }
1176 
1177 /*
1178  * Old IBM workstations have a DSDT bug wherein the SMBus object
1179  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1180  * prefix.  Work around this.
1181  */
1182 static bool acpi_ibm_smbus_match(acpi_handle handle)
1183 {
1184         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1185         struct acpi_buffer path = { sizeof(node_name), node_name };
1186 
1187         if (!dmi_name_in_vendors("IBM"))
1188                 return false;
1189 
1190         /* Look for SMBS object */
1191         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1192             strcmp("SMBS", path.pointer))
1193                 return false;
1194 
1195         /* Does it have the necessary (but misnamed) methods? */
1196         if (acpi_has_method(handle, "SBI") &&
1197             acpi_has_method(handle, "SBR") &&
1198             acpi_has_method(handle, "SBW"))
1199                 return true;
1200 
1201         return false;
1202 }
1203 
1204 static bool acpi_object_is_system_bus(acpi_handle handle)
1205 {
1206         acpi_handle tmp;
1207 
1208         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1209             tmp == handle)
1210                 return true;
1211         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1212             tmp == handle)
1213                 return true;
1214 
1215         return false;
1216 }
1217 
1218 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1219                                 int device_type)
1220 {
1221         acpi_status status;
1222         struct acpi_device_info *info;
1223         struct acpi_pnp_device_id_list *cid_list;
1224         int i;
1225 
1226         switch (device_type) {
1227         case ACPI_BUS_TYPE_DEVICE:
1228                 if (handle == ACPI_ROOT_OBJECT) {
1229                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1230                         break;
1231                 }
1232 
1233                 status = acpi_get_object_info(handle, &info);
1234                 if (ACPI_FAILURE(status)) {
1235                         pr_err(PREFIX "%s: Error reading device info\n",
1236                                         __func__);
1237                         return;
1238                 }
1239 
1240                 if (info->valid & ACPI_VALID_HID) {
1241                         acpi_add_id(pnp, info->hardware_id.string);
1242                         pnp->type.platform_id = 1;
1243                 }
1244                 if (info->valid & ACPI_VALID_CID) {
1245                         cid_list = &info->compatible_id_list;
1246                         for (i = 0; i < cid_list->count; i++)
1247                                 acpi_add_id(pnp, cid_list->ids[i].string);
1248                 }
1249                 if (info->valid & ACPI_VALID_ADR) {
1250                         pnp->bus_address = info->address;
1251                         pnp->type.bus_address = 1;
1252                 }
1253                 if (info->valid & ACPI_VALID_UID)
1254                         pnp->unique_id = kstrdup(info->unique_id.string,
1255                                                         GFP_KERNEL);
1256                 if (info->valid & ACPI_VALID_CLS)
1257                         acpi_add_id(pnp, info->class_code.string);
1258 
1259                 kfree(info);
1260 
1261                 /*
1262                  * Some devices don't reliably have _HIDs & _CIDs, so add
1263                  * synthetic HIDs to make sure drivers can find them.
1264                  */
1265                 if (acpi_is_video_device(handle))
1266                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1267                 else if (acpi_bay_match(handle))
1268                         acpi_add_id(pnp, ACPI_BAY_HID);
1269                 else if (acpi_dock_match(handle))
1270                         acpi_add_id(pnp, ACPI_DOCK_HID);
1271                 else if (acpi_ibm_smbus_match(handle))
1272                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1273                 else if (list_empty(&pnp->ids) &&
1274                          acpi_object_is_system_bus(handle)) {
1275                         /* \_SB, \_TZ, LNXSYBUS */
1276                         acpi_add_id(pnp, ACPI_BUS_HID);
1277                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1278                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1279                 }
1280 
1281                 break;
1282         case ACPI_BUS_TYPE_POWER:
1283                 acpi_add_id(pnp, ACPI_POWER_HID);
1284                 break;
1285         case ACPI_BUS_TYPE_PROCESSOR:
1286                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1287                 break;
1288         case ACPI_BUS_TYPE_THERMAL:
1289                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1290                 break;
1291         case ACPI_BUS_TYPE_POWER_BUTTON:
1292                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1293                 break;
1294         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1295                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1296                 break;
1297         }
1298 }
1299 
1300 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1301 {
1302         struct acpi_hardware_id *id, *tmp;
1303 
1304         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1305                 kfree_const(id->id);
1306                 kfree(id);
1307         }
1308         kfree(pnp->unique_id);
1309 }
1310 
1311 /**
1312  * acpi_dma_supported - Check DMA support for the specified device.
1313  * @adev: The pointer to acpi device
1314  *
1315  * Return false if DMA is not supported. Otherwise, return true
1316  */
1317 bool acpi_dma_supported(struct acpi_device *adev)
1318 {
1319         if (!adev)
1320                 return false;
1321 
1322         if (adev->flags.cca_seen)
1323                 return true;
1324 
1325         /*
1326         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1327         * DMA on "Intel platforms".  Presumably that includes all x86 and
1328         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1329         */
1330         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1331                 return true;
1332 
1333         return false;
1334 }
1335 
1336 /**
1337  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1338  * @adev: The pointer to acpi device
1339  *
1340  * Return enum dev_dma_attr.
1341  */
1342 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1343 {
1344         if (!acpi_dma_supported(adev))
1345                 return DEV_DMA_NOT_SUPPORTED;
1346 
1347         if (adev->flags.coherent_dma)
1348                 return DEV_DMA_COHERENT;
1349         else
1350                 return DEV_DMA_NON_COHERENT;
1351 }
1352 
1353 static void acpi_init_coherency(struct acpi_device *adev)
1354 {
1355         unsigned long long cca = 0;
1356         acpi_status status;
1357         struct acpi_device *parent = adev->parent;
1358 
1359         if (parent && parent->flags.cca_seen) {
1360                 /*
1361                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1362                  * already saw one.
1363                  */
1364                 adev->flags.cca_seen = 1;
1365                 cca = parent->flags.coherent_dma;
1366         } else {
1367                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1368                                                NULL, &cca);
1369                 if (ACPI_SUCCESS(status))
1370                         adev->flags.cca_seen = 1;
1371                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1372                         /*
1373                          * If architecture does not specify that _CCA is
1374                          * required for DMA-able devices (e.g. x86),
1375                          * we default to _CCA=1.
1376                          */
1377                         cca = 1;
1378                 else
1379                         acpi_handle_debug(adev->handle,
1380                                           "ACPI device is missing _CCA.\n");
1381         }
1382 
1383         adev->flags.coherent_dma = cca;
1384 }
1385 
1386 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1387                              int type, unsigned long long sta)
1388 {
1389         INIT_LIST_HEAD(&device->pnp.ids);
1390         device->device_type = type;
1391         device->handle = handle;
1392         device->parent = acpi_bus_get_parent(handle);
1393         device->fwnode.type = FWNODE_ACPI;
1394         acpi_set_device_status(device, sta);
1395         acpi_device_get_busid(device);
1396         acpi_set_pnp_ids(handle, &device->pnp, type);
1397         acpi_init_properties(device);
1398         acpi_bus_get_flags(device);
1399         device->flags.match_driver = false;
1400         device->flags.initialized = true;
1401         device->flags.visited = false;
1402         device_initialize(&device->dev);
1403         dev_set_uevent_suppress(&device->dev, true);
1404         acpi_init_coherency(device);
1405 }
1406 
1407 void acpi_device_add_finalize(struct acpi_device *device)
1408 {
1409         dev_set_uevent_suppress(&device->dev, false);
1410         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1411 }
1412 
1413 static int acpi_add_single_object(struct acpi_device **child,
1414                                   acpi_handle handle, int type,
1415                                   unsigned long long sta)
1416 {
1417         int result;
1418         struct acpi_device *device;
1419         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1420 
1421         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1422         if (!device) {
1423                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1424                 return -ENOMEM;
1425         }
1426 
1427         acpi_init_device_object(device, handle, type, sta);
1428         acpi_bus_get_power_flags(device);
1429         acpi_bus_get_wakeup_device_flags(device);
1430 
1431         result = acpi_device_add(device, acpi_device_release);
1432         if (result) {
1433                 acpi_device_release(&device->dev);
1434                 return result;
1435         }
1436 
1437         acpi_power_add_remove_device(device, true);
1438         acpi_device_add_finalize(device);
1439         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1440         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1441                 dev_name(&device->dev), (char *) buffer.pointer,
1442                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1443         kfree(buffer.pointer);
1444         *child = device;
1445         return 0;
1446 }
1447 
1448 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1449                                     unsigned long long *sta)
1450 {
1451         acpi_status status;
1452         acpi_object_type acpi_type;
1453 
1454         status = acpi_get_type(handle, &acpi_type);
1455         if (ACPI_FAILURE(status))
1456                 return -ENODEV;
1457 
1458         switch (acpi_type) {
1459         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1460         case ACPI_TYPE_DEVICE:
1461                 *type = ACPI_BUS_TYPE_DEVICE;
1462                 status = acpi_bus_get_status_handle(handle, sta);
1463                 if (ACPI_FAILURE(status))
1464                         return -ENODEV;
1465                 break;
1466         case ACPI_TYPE_PROCESSOR:
1467                 *type = ACPI_BUS_TYPE_PROCESSOR;
1468                 status = acpi_bus_get_status_handle(handle, sta);
1469                 if (ACPI_FAILURE(status))
1470                         return -ENODEV;
1471                 break;
1472         case ACPI_TYPE_THERMAL:
1473                 *type = ACPI_BUS_TYPE_THERMAL;
1474                 *sta = ACPI_STA_DEFAULT;
1475                 break;
1476         case ACPI_TYPE_POWER:
1477                 *type = ACPI_BUS_TYPE_POWER;
1478                 *sta = ACPI_STA_DEFAULT;
1479                 break;
1480         default:
1481                 return -ENODEV;
1482         }
1483 
1484         return 0;
1485 }
1486 
1487 bool acpi_device_is_present(struct acpi_device *adev)
1488 {
1489         if (adev->status.present || adev->status.functional)
1490                 return true;
1491 
1492         adev->flags.initialized = false;
1493         return false;
1494 }
1495 
1496 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1497                                        const char *idstr,
1498                                        const struct acpi_device_id **matchid)
1499 {
1500         const struct acpi_device_id *devid;
1501 
1502         if (handler->match)
1503                 return handler->match(idstr, matchid);
1504 
1505         for (devid = handler->ids; devid->id[0]; devid++)
1506                 if (!strcmp((char *)devid->id, idstr)) {
1507                         if (matchid)
1508                                 *matchid = devid;
1509 
1510                         return true;
1511                 }
1512 
1513         return false;
1514 }
1515 
1516 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1517                                         const struct acpi_device_id **matchid)
1518 {
1519         struct acpi_scan_handler *handler;
1520 
1521         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1522                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1523                         return handler;
1524 
1525         return NULL;
1526 }
1527 
1528 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1529 {
1530         if (!!hotplug->enabled == !!val)
1531                 return;
1532 
1533         mutex_lock(&acpi_scan_lock);
1534 
1535         hotplug->enabled = val;
1536 
1537         mutex_unlock(&acpi_scan_lock);
1538 }
1539 
1540 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1541 {
1542         struct acpi_hardware_id *hwid;
1543 
1544         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1545                 acpi_dock_add(adev);
1546                 return;
1547         }
1548         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1549                 struct acpi_scan_handler *handler;
1550 
1551                 handler = acpi_scan_match_handler(hwid->id, NULL);
1552                 if (handler) {
1553                         adev->flags.hotplug_notify = true;
1554                         break;
1555                 }
1556         }
1557 }
1558 
1559 static void acpi_device_dep_initialize(struct acpi_device *adev)
1560 {
1561         struct acpi_dep_data *dep;
1562         struct acpi_handle_list dep_devices;
1563         acpi_status status;
1564         int i;
1565 
1566         if (!acpi_has_method(adev->handle, "_DEP"))
1567                 return;
1568 
1569         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1570                                         &dep_devices);
1571         if (ACPI_FAILURE(status)) {
1572                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1573                 return;
1574         }
1575 
1576         for (i = 0; i < dep_devices.count; i++) {
1577                 struct acpi_device_info *info;
1578                 int skip;
1579 
1580                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1581                 if (ACPI_FAILURE(status)) {
1582                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1583                         continue;
1584                 }
1585 
1586                 /*
1587                  * Skip the dependency of Windows System Power
1588                  * Management Controller
1589                  */
1590                 skip = info->valid & ACPI_VALID_HID &&
1591                         !strcmp(info->hardware_id.string, "INT3396");
1592 
1593                 kfree(info);
1594 
1595                 if (skip)
1596                         continue;
1597 
1598                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1599                 if (!dep)
1600                         return;
1601 
1602                 dep->master = dep_devices.handles[i];
1603                 dep->slave  = adev->handle;
1604                 adev->dep_unmet++;
1605 
1606                 mutex_lock(&acpi_dep_list_lock);
1607                 list_add_tail(&dep->node , &acpi_dep_list);
1608                 mutex_unlock(&acpi_dep_list_lock);
1609         }
1610 }
1611 
1612 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1613                                       void *not_used, void **return_value)
1614 {
1615         struct acpi_device *device = NULL;
1616         int type;
1617         unsigned long long sta;
1618         int result;
1619 
1620         acpi_bus_get_device(handle, &device);
1621         if (device)
1622                 goto out;
1623 
1624         result = acpi_bus_type_and_status(handle, &type, &sta);
1625         if (result)
1626                 return AE_OK;
1627 
1628         if (type == ACPI_BUS_TYPE_POWER) {
1629                 acpi_add_power_resource(handle);
1630                 return AE_OK;
1631         }
1632 
1633         acpi_add_single_object(&device, handle, type, sta);
1634         if (!device)
1635                 return AE_CTRL_DEPTH;
1636 
1637         acpi_scan_init_hotplug(device);
1638         acpi_device_dep_initialize(device);
1639 
1640  out:
1641         if (!*return_value)
1642                 *return_value = device;
1643 
1644         return AE_OK;
1645 }
1646 
1647 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
1648 {
1649         bool *is_spi_i2c_slave_p = data;
1650 
1651         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1652                 return 1;
1653 
1654         /*
1655          * devices that are connected to UART still need to be enumerated to
1656          * platform bus
1657          */
1658         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1659                 *is_spi_i2c_slave_p = true;
1660 
1661          /* no need to do more checking */
1662         return -1;
1663 }
1664 
1665 static void acpi_default_enumeration(struct acpi_device *device)
1666 {
1667         struct list_head resource_list;
1668         bool is_spi_i2c_slave = false;
1669 
1670         /*
1671          * Do not enemerate SPI/I2C slaves as they will be enuerated by their
1672          * respective parents.
1673          */
1674         INIT_LIST_HEAD(&resource_list);
1675         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1676                                &is_spi_i2c_slave);
1677         acpi_dev_free_resource_list(&resource_list);
1678         if (!is_spi_i2c_slave)
1679                 acpi_create_platform_device(device);
1680 }
1681 
1682 static const struct acpi_device_id generic_device_ids[] = {
1683         {ACPI_DT_NAMESPACE_HID, },
1684         {"", },
1685 };
1686 
1687 static int acpi_generic_device_attach(struct acpi_device *adev,
1688                                       const struct acpi_device_id *not_used)
1689 {
1690         /*
1691          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1692          * below can be unconditional.
1693          */
1694         if (adev->data.of_compatible)
1695                 acpi_default_enumeration(adev);
1696 
1697         return 1;
1698 }
1699 
1700 static struct acpi_scan_handler generic_device_handler = {
1701         .ids = generic_device_ids,
1702         .attach = acpi_generic_device_attach,
1703 };
1704 
1705 static int acpi_scan_attach_handler(struct acpi_device *device)
1706 {
1707         struct acpi_hardware_id *hwid;
1708         int ret = 0;
1709 
1710         list_for_each_entry(hwid, &device->pnp.ids, list) {
1711                 const struct acpi_device_id *devid;
1712                 struct acpi_scan_handler *handler;
1713 
1714                 handler = acpi_scan_match_handler(hwid->id, &devid);
1715                 if (handler) {
1716                         if (!handler->attach) {
1717                                 device->pnp.type.platform_id = 0;
1718                                 continue;
1719                         }
1720                         device->handler = handler;
1721                         ret = handler->attach(device, devid);
1722                         if (ret > 0)
1723                                 break;
1724 
1725                         device->handler = NULL;
1726                         if (ret < 0)
1727                                 break;
1728                 }
1729         }
1730 
1731         return ret;
1732 }
1733 
1734 static void acpi_bus_attach(struct acpi_device *device)
1735 {
1736         struct acpi_device *child;
1737         acpi_handle ejd;
1738         int ret;
1739 
1740         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1741                 register_dock_dependent_device(device, ejd);
1742 
1743         acpi_bus_get_status(device);
1744         /* Skip devices that are not present. */
1745         if (!acpi_device_is_present(device)) {
1746                 device->flags.visited = false;
1747                 device->flags.power_manageable = 0;
1748                 return;
1749         }
1750         if (device->handler)
1751                 goto ok;
1752 
1753         if (!device->flags.initialized) {
1754                 device->flags.power_manageable =
1755                         device->power.states[ACPI_STATE_D0].flags.valid;
1756                 if (acpi_bus_init_power(device))
1757                         device->flags.power_manageable = 0;
1758 
1759                 device->flags.initialized = true;
1760         }
1761         device->flags.visited = false;
1762         ret = acpi_scan_attach_handler(device);
1763         if (ret < 0)
1764                 return;
1765 
1766         device->flags.match_driver = true;
1767         if (!ret) {
1768                 ret = device_attach(&device->dev);
1769                 if (ret < 0)
1770                         return;
1771 
1772                 if (!ret && device->pnp.type.platform_id)
1773                         acpi_default_enumeration(device);
1774         }
1775         device->flags.visited = true;
1776 
1777  ok:
1778         list_for_each_entry(child, &device->children, node)
1779                 acpi_bus_attach(child);
1780 
1781         if (device->handler && device->handler->hotplug.notify_online)
1782                 device->handler->hotplug.notify_online(device);
1783 }
1784 
1785 void acpi_walk_dep_device_list(acpi_handle handle)
1786 {
1787         struct acpi_dep_data *dep, *tmp;
1788         struct acpi_device *adev;
1789 
1790         mutex_lock(&acpi_dep_list_lock);
1791         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1792                 if (dep->master == handle) {
1793                         acpi_bus_get_device(dep->slave, &adev);
1794                         if (!adev)
1795                                 continue;
1796 
1797                         adev->dep_unmet--;
1798                         if (!adev->dep_unmet)
1799                                 acpi_bus_attach(adev);
1800                         list_del(&dep->node);
1801                         kfree(dep);
1802                 }
1803         }
1804         mutex_unlock(&acpi_dep_list_lock);
1805 }
1806 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1807 
1808 /**
1809  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1810  * @handle: Root of the namespace scope to scan.
1811  *
1812  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1813  * found devices.
1814  *
1815  * If no devices were found, -ENODEV is returned, but it does not mean that
1816  * there has been a real error.  There just have been no suitable ACPI objects
1817  * in the table trunk from which the kernel could create a device and add an
1818  * appropriate driver.
1819  *
1820  * Must be called under acpi_scan_lock.
1821  */
1822 int acpi_bus_scan(acpi_handle handle)
1823 {
1824         void *device = NULL;
1825 
1826         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1827                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1828                                     acpi_bus_check_add, NULL, NULL, &device);
1829 
1830         if (device) {
1831                 acpi_bus_attach(device);
1832                 return 0;
1833         }
1834         return -ENODEV;
1835 }
1836 EXPORT_SYMBOL(acpi_bus_scan);
1837 
1838 /**
1839  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1840  * @adev: Root of the ACPI namespace scope to walk.
1841  *
1842  * Must be called under acpi_scan_lock.
1843  */
1844 void acpi_bus_trim(struct acpi_device *adev)
1845 {
1846         struct acpi_scan_handler *handler = adev->handler;
1847         struct acpi_device *child;
1848 
1849         list_for_each_entry_reverse(child, &adev->children, node)
1850                 acpi_bus_trim(child);
1851 
1852         adev->flags.match_driver = false;
1853         if (handler) {
1854                 if (handler->detach)
1855                         handler->detach(adev);
1856 
1857                 adev->handler = NULL;
1858         } else {
1859                 device_release_driver(&adev->dev);
1860         }
1861         /*
1862          * Most likely, the device is going away, so put it into D3cold before
1863          * that.
1864          */
1865         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1866         adev->flags.initialized = false;
1867         adev->flags.visited = false;
1868 }
1869 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1870 
1871 static int acpi_bus_scan_fixed(void)
1872 {
1873         int result = 0;
1874 
1875         /*
1876          * Enumerate all fixed-feature devices.
1877          */
1878         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1879                 struct acpi_device *device = NULL;
1880 
1881                 result = acpi_add_single_object(&device, NULL,
1882                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1883                                                 ACPI_STA_DEFAULT);
1884                 if (result)
1885                         return result;
1886 
1887                 device->flags.match_driver = true;
1888                 result = device_attach(&device->dev);
1889                 if (result < 0)
1890                         return result;
1891 
1892                 device_init_wakeup(&device->dev, true);
1893         }
1894 
1895         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1896                 struct acpi_device *device = NULL;
1897 
1898                 result = acpi_add_single_object(&device, NULL,
1899                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1900                                                 ACPI_STA_DEFAULT);
1901                 if (result)
1902                         return result;
1903 
1904                 device->flags.match_driver = true;
1905                 result = device_attach(&device->dev);
1906         }
1907 
1908         return result < 0 ? result : 0;
1909 }
1910 
1911 int __init acpi_scan_init(void)
1912 {
1913         int result;
1914 
1915         acpi_pci_root_init();
1916         acpi_pci_link_init();
1917         acpi_processor_init();
1918         acpi_lpss_init();
1919         acpi_apd_init();
1920         acpi_cmos_rtc_init();
1921         acpi_container_init();
1922         acpi_memory_hotplug_init();
1923         acpi_pnp_init();
1924         acpi_int340x_thermal_init();
1925 
1926         acpi_scan_add_handler(&generic_device_handler);
1927 
1928         mutex_lock(&acpi_scan_lock);
1929         /*
1930          * Enumerate devices in the ACPI namespace.
1931          */
1932         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
1933         if (result)
1934                 goto out;
1935 
1936         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
1937         if (result)
1938                 goto out;
1939 
1940         /* Fixed feature devices do not exist on HW-reduced platform */
1941         if (!acpi_gbl_reduced_hardware) {
1942                 result = acpi_bus_scan_fixed();
1943                 if (result) {
1944                         acpi_detach_data(acpi_root->handle,
1945                                          acpi_scan_drop_device);
1946                         acpi_device_del(acpi_root);
1947                         put_device(&acpi_root->dev);
1948                         goto out;
1949                 }
1950         }
1951 
1952         acpi_update_all_gpes();
1953 
1954  out:
1955         mutex_unlock(&acpi_scan_lock);
1956         return result;
1957 }
1958 
1959 static struct acpi_probe_entry *ape;
1960 static int acpi_probe_count;
1961 static DEFINE_SPINLOCK(acpi_probe_lock);
1962 
1963 static int __init acpi_match_madt(struct acpi_subtable_header *header,
1964                                   const unsigned long end)
1965 {
1966         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
1967                 if (!ape->probe_subtbl(header, end))
1968                         acpi_probe_count++;
1969 
1970         return 0;
1971 }
1972 
1973 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
1974 {
1975         int count = 0;
1976 
1977         if (acpi_disabled)
1978                 return 0;
1979 
1980         spin_lock(&acpi_probe_lock);
1981         for (ape = ap_head; nr; ape++, nr--) {
1982                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
1983                         acpi_probe_count = 0;
1984                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
1985                         count += acpi_probe_count;
1986                 } else {
1987                         int res;
1988                         res = acpi_table_parse(ape->id, ape->probe_table);
1989                         if (!res)
1990                                 count++;
1991                 }
1992         }
1993         spin_unlock(&acpi_probe_lock);
1994 
1995         return count;
1996 }
1997 

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