Version:  2.0.40 2.2.26 2.4.37 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16

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 
 15 #include <asm/pgtable.h>
 16 
 17 #include "internal.h"
 18 
 19 #define _COMPONENT              ACPI_BUS_COMPONENT
 20 ACPI_MODULE_NAME("scan");
 21 extern struct acpi_device *acpi_root;
 22 
 23 #define ACPI_BUS_CLASS                  "system_bus"
 24 #define ACPI_BUS_HID                    "LNXSYBUS"
 25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
 26 
 27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
 28 
 29 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
 30 
 31 /*
 32  * If set, devices will be hot-removed even if they cannot be put offline
 33  * gracefully (from the kernel's standpoint).
 34  */
 35 bool acpi_force_hot_remove;
 36 
 37 static const char *dummy_hid = "device";
 38 
 39 static LIST_HEAD(acpi_bus_id_list);
 40 static DEFINE_MUTEX(acpi_scan_lock);
 41 static LIST_HEAD(acpi_scan_handlers_list);
 42 DEFINE_MUTEX(acpi_device_lock);
 43 LIST_HEAD(acpi_wakeup_device_list);
 44 static DEFINE_MUTEX(acpi_hp_context_lock);
 45 
 46 struct acpi_device_bus_id{
 47         char bus_id[15];
 48         unsigned int instance_no;
 49         struct list_head node;
 50 };
 51 
 52 void acpi_scan_lock_acquire(void)
 53 {
 54         mutex_lock(&acpi_scan_lock);
 55 }
 56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
 57 
 58 void acpi_scan_lock_release(void)
 59 {
 60         mutex_unlock(&acpi_scan_lock);
 61 }
 62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
 63 
 64 void acpi_lock_hp_context(void)
 65 {
 66         mutex_lock(&acpi_hp_context_lock);
 67 }
 68 
 69 void acpi_unlock_hp_context(void)
 70 {
 71         mutex_unlock(&acpi_hp_context_lock);
 72 }
 73 
 74 void acpi_initialize_hp_context(struct acpi_device *adev,
 75                                 struct acpi_hotplug_context *hp,
 76                                 int (*notify)(struct acpi_device *, u32),
 77                                 void (*uevent)(struct acpi_device *, u32))
 78 {
 79         acpi_lock_hp_context();
 80         acpi_set_hp_context(adev, hp, notify, uevent, NULL);
 81         acpi_unlock_hp_context();
 82 }
 83 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
 84 
 85 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
 86 {
 87         if (!handler)
 88                 return -EINVAL;
 89 
 90         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
 91         return 0;
 92 }
 93 
 94 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 95                                        const char *hotplug_profile_name)
 96 {
 97         int error;
 98 
 99         error = acpi_scan_add_handler(handler);
100         if (error)
101                 return error;
102 
103         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
104         return 0;
105 }
106 
107 /*
108  * Creates hid/cid(s) string needed for modalias and uevent
109  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
110  * char *modalias: "acpi:IBM0001:ACPI0001"
111  * Return: 0: no _HID and no _CID
112  *         -EINVAL: output error
113  *         -ENOMEM: output is truncated
114 */
115 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
116                            int size)
117 {
118         int len;
119         int count;
120         struct acpi_hardware_id *id;
121 
122         if (list_empty(&acpi_dev->pnp.ids))
123                 return 0;
124 
125         len = snprintf(modalias, size, "acpi:");
126         size -= len;
127 
128         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
129                 count = snprintf(&modalias[len], size, "%s:", id->id);
130                 if (count < 0)
131                         return EINVAL;
132                 if (count >= size)
133                         return -ENOMEM;
134                 len += count;
135                 size -= count;
136         }
137 
138         modalias[len] = '\0';
139         return len;
140 }
141 
142 /*
143  * Creates uevent modalias field for ACPI enumerated devices.
144  * Because the other buses does not support ACPI HIDs & CIDs.
145  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
146  * "acpi:IBM0001:ACPI0001"
147  */
148 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
149 {
150         struct acpi_device *acpi_dev;
151         int len;
152 
153         acpi_dev = ACPI_COMPANION(dev);
154         if (!acpi_dev)
155                 return -ENODEV;
156 
157         /* Fall back to bus specific way of modalias exporting */
158         if (list_empty(&acpi_dev->pnp.ids))
159                 return -ENODEV;
160 
161         if (add_uevent_var(env, "MODALIAS="))
162                 return -ENOMEM;
163         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
164                                 sizeof(env->buf) - env->buflen);
165         if (len <= 0)
166                 return len;
167         env->buflen += len;
168         return 0;
169 }
170 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
171 
172 /*
173  * Creates modalias sysfs attribute for ACPI enumerated devices.
174  * Because the other buses does not support ACPI HIDs & CIDs.
175  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
176  * "acpi:IBM0001:ACPI0001"
177  */
178 int acpi_device_modalias(struct device *dev, char *buf, int size)
179 {
180         struct acpi_device *acpi_dev;
181         int len;
182 
183         acpi_dev = ACPI_COMPANION(dev);
184         if (!acpi_dev)
185                 return -ENODEV;
186 
187         /* Fall back to bus specific way of modalias exporting */
188         if (list_empty(&acpi_dev->pnp.ids))
189                 return -ENODEV;
190 
191         len = create_modalias(acpi_dev, buf, size -1);
192         if (len <= 0)
193                 return len;
194         buf[len++] = '\n';
195         return len;
196 }
197 EXPORT_SYMBOL_GPL(acpi_device_modalias);
198 
199 static ssize_t
200 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
201         struct acpi_device *acpi_dev = to_acpi_device(dev);
202         int len;
203 
204         len = create_modalias(acpi_dev, buf, 1024);
205         if (len <= 0)
206                 return len;
207         buf[len++] = '\n';
208         return len;
209 }
210 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
211 
212 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
213 {
214         struct acpi_device_physical_node *pn;
215         bool offline = true;
216 
217         mutex_lock(&adev->physical_node_lock);
218 
219         list_for_each_entry(pn, &adev->physical_node_list, node)
220                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
221                         if (uevent)
222                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
223 
224                         offline = false;
225                         break;
226                 }
227 
228         mutex_unlock(&adev->physical_node_lock);
229         return offline;
230 }
231 
232 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
233                                     void **ret_p)
234 {
235         struct acpi_device *device = NULL;
236         struct acpi_device_physical_node *pn;
237         bool second_pass = (bool)data;
238         acpi_status status = AE_OK;
239 
240         if (acpi_bus_get_device(handle, &device))
241                 return AE_OK;
242 
243         if (device->handler && !device->handler->hotplug.enabled) {
244                 *ret_p = &device->dev;
245                 return AE_SUPPORT;
246         }
247 
248         mutex_lock(&device->physical_node_lock);
249 
250         list_for_each_entry(pn, &device->physical_node_list, node) {
251                 int ret;
252 
253                 if (second_pass) {
254                         /* Skip devices offlined by the first pass. */
255                         if (pn->put_online)
256                                 continue;
257                 } else {
258                         pn->put_online = false;
259                 }
260                 ret = device_offline(pn->dev);
261                 if (acpi_force_hot_remove)
262                         continue;
263 
264                 if (ret >= 0) {
265                         pn->put_online = !ret;
266                 } else {
267                         *ret_p = pn->dev;
268                         if (second_pass) {
269                                 status = AE_ERROR;
270                                 break;
271                         }
272                 }
273         }
274 
275         mutex_unlock(&device->physical_node_lock);
276 
277         return status;
278 }
279 
280 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
281                                    void **ret_p)
282 {
283         struct acpi_device *device = NULL;
284         struct acpi_device_physical_node *pn;
285 
286         if (acpi_bus_get_device(handle, &device))
287                 return AE_OK;
288 
289         mutex_lock(&device->physical_node_lock);
290 
291         list_for_each_entry(pn, &device->physical_node_list, node)
292                 if (pn->put_online) {
293                         device_online(pn->dev);
294                         pn->put_online = false;
295                 }
296 
297         mutex_unlock(&device->physical_node_lock);
298 
299         return AE_OK;
300 }
301 
302 static int acpi_scan_try_to_offline(struct acpi_device *device)
303 {
304         acpi_handle handle = device->handle;
305         struct device *errdev = NULL;
306         acpi_status status;
307 
308         /*
309          * Carry out two passes here and ignore errors in the first pass,
310          * because if the devices in question are memory blocks and
311          * CONFIG_MEMCG is set, one of the blocks may hold data structures
312          * that the other blocks depend on, but it is not known in advance which
313          * block holds them.
314          *
315          * If the first pass is successful, the second one isn't needed, though.
316          */
317         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
318                                      NULL, acpi_bus_offline, (void *)false,
319                                      (void **)&errdev);
320         if (status == AE_SUPPORT) {
321                 dev_warn(errdev, "Offline disabled.\n");
322                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
323                                     acpi_bus_online, NULL, NULL, NULL);
324                 return -EPERM;
325         }
326         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
327         if (errdev) {
328                 errdev = NULL;
329                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
330                                     NULL, acpi_bus_offline, (void *)true,
331                                     (void **)&errdev);
332                 if (!errdev || acpi_force_hot_remove)
333                         acpi_bus_offline(handle, 0, (void *)true,
334                                          (void **)&errdev);
335 
336                 if (errdev && !acpi_force_hot_remove) {
337                         dev_warn(errdev, "Offline failed.\n");
338                         acpi_bus_online(handle, 0, NULL, NULL);
339                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
340                                             ACPI_UINT32_MAX, acpi_bus_online,
341                                             NULL, NULL, NULL);
342                         return -EBUSY;
343                 }
344         }
345         return 0;
346 }
347 
348 static int acpi_scan_hot_remove(struct acpi_device *device)
349 {
350         acpi_handle handle = device->handle;
351         unsigned long long sta;
352         acpi_status status;
353 
354         if (device->handler->hotplug.demand_offline && !acpi_force_hot_remove) {
355                 if (!acpi_scan_is_offline(device, true))
356                         return -EBUSY;
357         } else {
358                 int error = acpi_scan_try_to_offline(device);
359                 if (error)
360                         return error;
361         }
362 
363         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
364                 "Hot-removing device %s...\n", dev_name(&device->dev)));
365 
366         acpi_bus_trim(device);
367 
368         acpi_evaluate_lck(handle, 0);
369         /*
370          * TBD: _EJD support.
371          */
372         status = acpi_evaluate_ej0(handle);
373         if (status == AE_NOT_FOUND)
374                 return -ENODEV;
375         else if (ACPI_FAILURE(status))
376                 return -EIO;
377 
378         /*
379          * Verify if eject was indeed successful.  If not, log an error
380          * message.  No need to call _OST since _EJ0 call was made OK.
381          */
382         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
383         if (ACPI_FAILURE(status)) {
384                 acpi_handle_warn(handle,
385                         "Status check after eject failed (0x%x)\n", status);
386         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
387                 acpi_handle_warn(handle,
388                         "Eject incomplete - status 0x%llx\n", sta);
389         }
390 
391         return 0;
392 }
393 
394 static int acpi_scan_device_not_present(struct acpi_device *adev)
395 {
396         if (!acpi_device_enumerated(adev)) {
397                 dev_warn(&adev->dev, "Still not present\n");
398                 return -EALREADY;
399         }
400         acpi_bus_trim(adev);
401         return 0;
402 }
403 
404 static int acpi_scan_device_check(struct acpi_device *adev)
405 {
406         int error;
407 
408         acpi_bus_get_status(adev);
409         if (adev->status.present || adev->status.functional) {
410                 /*
411                  * This function is only called for device objects for which
412                  * matching scan handlers exist.  The only situation in which
413                  * the scan handler is not attached to this device object yet
414                  * is when the device has just appeared (either it wasn't
415                  * present at all before or it was removed and then added
416                  * again).
417                  */
418                 if (adev->handler) {
419                         dev_warn(&adev->dev, "Already enumerated\n");
420                         return -EALREADY;
421                 }
422                 error = acpi_bus_scan(adev->handle);
423                 if (error) {
424                         dev_warn(&adev->dev, "Namespace scan failure\n");
425                         return error;
426                 }
427                 if (!adev->handler) {
428                         dev_warn(&adev->dev, "Enumeration failure\n");
429                         error = -ENODEV;
430                 }
431         } else {
432                 error = acpi_scan_device_not_present(adev);
433         }
434         return error;
435 }
436 
437 static int acpi_scan_bus_check(struct acpi_device *adev)
438 {
439         struct acpi_scan_handler *handler = adev->handler;
440         struct acpi_device *child;
441         int error;
442 
443         acpi_bus_get_status(adev);
444         if (!(adev->status.present || adev->status.functional)) {
445                 acpi_scan_device_not_present(adev);
446                 return 0;
447         }
448         if (handler && handler->hotplug.scan_dependent)
449                 return handler->hotplug.scan_dependent(adev);
450 
451         error = acpi_bus_scan(adev->handle);
452         if (error) {
453                 dev_warn(&adev->dev, "Namespace scan failure\n");
454                 return error;
455         }
456         list_for_each_entry(child, &adev->children, node) {
457                 error = acpi_scan_bus_check(child);
458                 if (error)
459                         return error;
460         }
461         return 0;
462 }
463 
464 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
465 {
466         switch (type) {
467         case ACPI_NOTIFY_BUS_CHECK:
468                 return acpi_scan_bus_check(adev);
469         case ACPI_NOTIFY_DEVICE_CHECK:
470                 return acpi_scan_device_check(adev);
471         case ACPI_NOTIFY_EJECT_REQUEST:
472         case ACPI_OST_EC_OSPM_EJECT:
473                 if (adev->handler && !adev->handler->hotplug.enabled) {
474                         dev_info(&adev->dev, "Eject disabled\n");
475                         return -EPERM;
476                 }
477                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
478                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
479                 return acpi_scan_hot_remove(adev);
480         }
481         return -EINVAL;
482 }
483 
484 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
485 {
486         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
487         int error = -ENODEV;
488 
489         lock_device_hotplug();
490         mutex_lock(&acpi_scan_lock);
491 
492         /*
493          * The device object's ACPI handle cannot become invalid as long as we
494          * are holding acpi_scan_lock, but it might have become invalid before
495          * that lock was acquired.
496          */
497         if (adev->handle == INVALID_ACPI_HANDLE)
498                 goto err_out;
499 
500         if (adev->flags.is_dock_station) {
501                 error = dock_notify(adev, src);
502         } else if (adev->flags.hotplug_notify) {
503                 error = acpi_generic_hotplug_event(adev, src);
504                 if (error == -EPERM) {
505                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
506                         goto err_out;
507                 }
508         } else {
509                 int (*notify)(struct acpi_device *, u32);
510 
511                 acpi_lock_hp_context();
512                 notify = adev->hp ? adev->hp->notify : NULL;
513                 acpi_unlock_hp_context();
514                 /*
515                  * There may be additional notify handlers for device objects
516                  * without the .event() callback, so ignore them here.
517                  */
518                 if (notify)
519                         error = notify(adev, src);
520                 else
521                         goto out;
522         }
523         if (!error)
524                 ost_code = ACPI_OST_SC_SUCCESS;
525 
526  err_out:
527         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
528 
529  out:
530         acpi_bus_put_acpi_device(adev);
531         mutex_unlock(&acpi_scan_lock);
532         unlock_device_hotplug();
533 }
534 
535 static ssize_t real_power_state_show(struct device *dev,
536                                      struct device_attribute *attr, char *buf)
537 {
538         struct acpi_device *adev = to_acpi_device(dev);
539         int state;
540         int ret;
541 
542         ret = acpi_device_get_power(adev, &state);
543         if (ret)
544                 return ret;
545 
546         return sprintf(buf, "%s\n", acpi_power_state_string(state));
547 }
548 
549 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
550 
551 static ssize_t power_state_show(struct device *dev,
552                                 struct device_attribute *attr, char *buf)
553 {
554         struct acpi_device *adev = to_acpi_device(dev);
555 
556         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
557 }
558 
559 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
560 
561 static ssize_t
562 acpi_eject_store(struct device *d, struct device_attribute *attr,
563                 const char *buf, size_t count)
564 {
565         struct acpi_device *acpi_device = to_acpi_device(d);
566         acpi_object_type not_used;
567         acpi_status status;
568 
569         if (!count || buf[0] != '1')
570                 return -EINVAL;
571 
572         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
573             && !acpi_device->driver)
574                 return -ENODEV;
575 
576         status = acpi_get_type(acpi_device->handle, &not_used);
577         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
578                 return -ENODEV;
579 
580         get_device(&acpi_device->dev);
581         status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
582         if (ACPI_SUCCESS(status))
583                 return count;
584 
585         put_device(&acpi_device->dev);
586         acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
587                           ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
588         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
589 }
590 
591 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
592 
593 static ssize_t
594 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
595         struct acpi_device *acpi_dev = to_acpi_device(dev);
596 
597         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
598 }
599 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
600 
601 static ssize_t acpi_device_uid_show(struct device *dev,
602                                     struct device_attribute *attr, char *buf)
603 {
604         struct acpi_device *acpi_dev = to_acpi_device(dev);
605 
606         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
607 }
608 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
609 
610 static ssize_t acpi_device_adr_show(struct device *dev,
611                                     struct device_attribute *attr, char *buf)
612 {
613         struct acpi_device *acpi_dev = to_acpi_device(dev);
614 
615         return sprintf(buf, "0x%08x\n",
616                        (unsigned int)(acpi_dev->pnp.bus_address));
617 }
618 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
619 
620 static ssize_t
621 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
622         struct acpi_device *acpi_dev = to_acpi_device(dev);
623         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
624         int result;
625 
626         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
627         if (result)
628                 goto end;
629 
630         result = sprintf(buf, "%s\n", (char*)path.pointer);
631         kfree(path.pointer);
632 end:
633         return result;
634 }
635 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
636 
637 /* sysfs file that shows description text from the ACPI _STR method */
638 static ssize_t description_show(struct device *dev,
639                                 struct device_attribute *attr,
640                                 char *buf) {
641         struct acpi_device *acpi_dev = to_acpi_device(dev);
642         int result;
643 
644         if (acpi_dev->pnp.str_obj == NULL)
645                 return 0;
646 
647         /*
648          * The _STR object contains a Unicode identifier for a device.
649          * We need to convert to utf-8 so it can be displayed.
650          */
651         result = utf16s_to_utf8s(
652                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
653                 acpi_dev->pnp.str_obj->buffer.length,
654                 UTF16_LITTLE_ENDIAN, buf,
655                 PAGE_SIZE);
656 
657         buf[result++] = '\n';
658 
659         return result;
660 }
661 static DEVICE_ATTR(description, 0444, description_show, NULL);
662 
663 static ssize_t
664 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
665                      char *buf) {
666         struct acpi_device *acpi_dev = to_acpi_device(dev);
667 
668         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
669 }
670 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
671 
672 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
673                                 char *buf) {
674         struct acpi_device *acpi_dev = to_acpi_device(dev);
675         acpi_status status;
676         unsigned long long sta;
677 
678         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
679         if (ACPI_FAILURE(status))
680                 return -ENODEV;
681 
682         return sprintf(buf, "%llu\n", sta);
683 }
684 static DEVICE_ATTR_RO(status);
685 
686 static int acpi_device_setup_files(struct acpi_device *dev)
687 {
688         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
689         acpi_status status;
690         unsigned long long sun;
691         int result = 0;
692 
693         /*
694          * Devices gotten from FADT don't have a "path" attribute
695          */
696         if (dev->handle) {
697                 result = device_create_file(&dev->dev, &dev_attr_path);
698                 if (result)
699                         goto end;
700         }
701 
702         if (!list_empty(&dev->pnp.ids)) {
703                 result = device_create_file(&dev->dev, &dev_attr_hid);
704                 if (result)
705                         goto end;
706 
707                 result = device_create_file(&dev->dev, &dev_attr_modalias);
708                 if (result)
709                         goto end;
710         }
711 
712         /*
713          * If device has _STR, 'description' file is created
714          */
715         if (acpi_has_method(dev->handle, "_STR")) {
716                 status = acpi_evaluate_object(dev->handle, "_STR",
717                                         NULL, &buffer);
718                 if (ACPI_FAILURE(status))
719                         buffer.pointer = NULL;
720                 dev->pnp.str_obj = buffer.pointer;
721                 result = device_create_file(&dev->dev, &dev_attr_description);
722                 if (result)
723                         goto end;
724         }
725 
726         if (dev->pnp.type.bus_address)
727                 result = device_create_file(&dev->dev, &dev_attr_adr);
728         if (dev->pnp.unique_id)
729                 result = device_create_file(&dev->dev, &dev_attr_uid);
730 
731         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
732         if (ACPI_SUCCESS(status)) {
733                 dev->pnp.sun = (unsigned long)sun;
734                 result = device_create_file(&dev->dev, &dev_attr_sun);
735                 if (result)
736                         goto end;
737         } else {
738                 dev->pnp.sun = (unsigned long)-1;
739         }
740 
741         if (acpi_has_method(dev->handle, "_STA")) {
742                 result = device_create_file(&dev->dev, &dev_attr_status);
743                 if (result)
744                         goto end;
745         }
746 
747         /*
748          * If device has _EJ0, 'eject' file is created that is used to trigger
749          * hot-removal function from userland.
750          */
751         if (acpi_has_method(dev->handle, "_EJ0")) {
752                 result = device_create_file(&dev->dev, &dev_attr_eject);
753                 if (result)
754                         return result;
755         }
756 
757         if (dev->flags.power_manageable) {
758                 result = device_create_file(&dev->dev, &dev_attr_power_state);
759                 if (result)
760                         return result;
761 
762                 if (dev->power.flags.power_resources)
763                         result = device_create_file(&dev->dev,
764                                                     &dev_attr_real_power_state);
765         }
766 
767 end:
768         return result;
769 }
770 
771 static void acpi_device_remove_files(struct acpi_device *dev)
772 {
773         if (dev->flags.power_manageable) {
774                 device_remove_file(&dev->dev, &dev_attr_power_state);
775                 if (dev->power.flags.power_resources)
776                         device_remove_file(&dev->dev,
777                                            &dev_attr_real_power_state);
778         }
779 
780         /*
781          * If device has _STR, remove 'description' file
782          */
783         if (acpi_has_method(dev->handle, "_STR")) {
784                 kfree(dev->pnp.str_obj);
785                 device_remove_file(&dev->dev, &dev_attr_description);
786         }
787         /*
788          * If device has _EJ0, remove 'eject' file.
789          */
790         if (acpi_has_method(dev->handle, "_EJ0"))
791                 device_remove_file(&dev->dev, &dev_attr_eject);
792 
793         if (acpi_has_method(dev->handle, "_SUN"))
794                 device_remove_file(&dev->dev, &dev_attr_sun);
795 
796         if (dev->pnp.unique_id)
797                 device_remove_file(&dev->dev, &dev_attr_uid);
798         if (dev->pnp.type.bus_address)
799                 device_remove_file(&dev->dev, &dev_attr_adr);
800         device_remove_file(&dev->dev, &dev_attr_modalias);
801         device_remove_file(&dev->dev, &dev_attr_hid);
802         if (acpi_has_method(dev->handle, "_STA"))
803                 device_remove_file(&dev->dev, &dev_attr_status);
804         if (dev->handle)
805                 device_remove_file(&dev->dev, &dev_attr_path);
806 }
807 /* --------------------------------------------------------------------------
808                         ACPI Bus operations
809    -------------------------------------------------------------------------- */
810 
811 static const struct acpi_device_id *__acpi_match_device(
812         struct acpi_device *device, const struct acpi_device_id *ids)
813 {
814         const struct acpi_device_id *id;
815         struct acpi_hardware_id *hwid;
816 
817         /*
818          * If the device is not present, it is unnecessary to load device
819          * driver for it.
820          */
821         if (!device->status.present)
822                 return NULL;
823 
824         for (id = ids; id->id[0]; id++)
825                 list_for_each_entry(hwid, &device->pnp.ids, list)
826                         if (!strcmp((char *) id->id, hwid->id))
827                                 return id;
828 
829         return NULL;
830 }
831 
832 /**
833  * acpi_match_device - Match a struct device against a given list of ACPI IDs
834  * @ids: Array of struct acpi_device_id object to match against.
835  * @dev: The device structure to match.
836  *
837  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
838  * object for that handle and use that object to match against a given list of
839  * device IDs.
840  *
841  * Return a pointer to the first matching ID on success or %NULL on failure.
842  */
843 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
844                                                const struct device *dev)
845 {
846         struct acpi_device *adev;
847         acpi_handle handle = ACPI_HANDLE(dev);
848 
849         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
850                 return NULL;
851 
852         return __acpi_match_device(adev, ids);
853 }
854 EXPORT_SYMBOL_GPL(acpi_match_device);
855 
856 int acpi_match_device_ids(struct acpi_device *device,
857                           const struct acpi_device_id *ids)
858 {
859         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
860 }
861 EXPORT_SYMBOL(acpi_match_device_ids);
862 
863 static void acpi_free_power_resources_lists(struct acpi_device *device)
864 {
865         int i;
866 
867         if (device->wakeup.flags.valid)
868                 acpi_power_resources_list_free(&device->wakeup.resources);
869 
870         if (!device->flags.power_manageable)
871                 return;
872 
873         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
874                 struct acpi_device_power_state *ps = &device->power.states[i];
875                 acpi_power_resources_list_free(&ps->resources);
876         }
877 }
878 
879 static void acpi_device_release(struct device *dev)
880 {
881         struct acpi_device *acpi_dev = to_acpi_device(dev);
882 
883         acpi_free_pnp_ids(&acpi_dev->pnp);
884         acpi_free_power_resources_lists(acpi_dev);
885         kfree(acpi_dev);
886 }
887 
888 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
889 {
890         struct acpi_device *acpi_dev = to_acpi_device(dev);
891         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
892 
893         return acpi_dev->flags.match_driver
894                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
895 }
896 
897 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
898 {
899         struct acpi_device *acpi_dev = to_acpi_device(dev);
900         int len;
901 
902         if (list_empty(&acpi_dev->pnp.ids))
903                 return 0;
904 
905         if (add_uevent_var(env, "MODALIAS="))
906                 return -ENOMEM;
907         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
908                               sizeof(env->buf) - env->buflen);
909         if (len <= 0)
910                 return len;
911         env->buflen += len;
912         return 0;
913 }
914 
915 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
916 {
917         struct acpi_device *device = data;
918 
919         device->driver->ops.notify(device, event);
920 }
921 
922 static acpi_status acpi_device_notify_fixed(void *data)
923 {
924         struct acpi_device *device = data;
925 
926         /* Fixed hardware devices have no handles */
927         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
928         return AE_OK;
929 }
930 
931 static int acpi_device_install_notify_handler(struct acpi_device *device)
932 {
933         acpi_status status;
934 
935         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
936                 status =
937                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
938                                                      acpi_device_notify_fixed,
939                                                      device);
940         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
941                 status =
942                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
943                                                      acpi_device_notify_fixed,
944                                                      device);
945         else
946                 status = acpi_install_notify_handler(device->handle,
947                                                      ACPI_DEVICE_NOTIFY,
948                                                      acpi_device_notify,
949                                                      device);
950 
951         if (ACPI_FAILURE(status))
952                 return -EINVAL;
953         return 0;
954 }
955 
956 static void acpi_device_remove_notify_handler(struct acpi_device *device)
957 {
958         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
959                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
960                                                 acpi_device_notify_fixed);
961         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
962                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
963                                                 acpi_device_notify_fixed);
964         else
965                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
966                                            acpi_device_notify);
967 }
968 
969 static int acpi_device_probe(struct device *dev)
970 {
971         struct acpi_device *acpi_dev = to_acpi_device(dev);
972         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
973         int ret;
974 
975         if (acpi_dev->handler)
976                 return -EINVAL;
977 
978         if (!acpi_drv->ops.add)
979                 return -ENOSYS;
980 
981         ret = acpi_drv->ops.add(acpi_dev);
982         if (ret)
983                 return ret;
984 
985         acpi_dev->driver = acpi_drv;
986         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
987                           "Driver [%s] successfully bound to device [%s]\n",
988                           acpi_drv->name, acpi_dev->pnp.bus_id));
989 
990         if (acpi_drv->ops.notify) {
991                 ret = acpi_device_install_notify_handler(acpi_dev);
992                 if (ret) {
993                         if (acpi_drv->ops.remove)
994                                 acpi_drv->ops.remove(acpi_dev);
995 
996                         acpi_dev->driver = NULL;
997                         acpi_dev->driver_data = NULL;
998                         return ret;
999                 }
1000         }
1001 
1002         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
1003                           acpi_drv->name, acpi_dev->pnp.bus_id));
1004         get_device(dev);
1005         return 0;
1006 }
1007 
1008 static int acpi_device_remove(struct device * dev)
1009 {
1010         struct acpi_device *acpi_dev = to_acpi_device(dev);
1011         struct acpi_driver *acpi_drv = acpi_dev->driver;
1012 
1013         if (acpi_drv) {
1014                 if (acpi_drv->ops.notify)
1015                         acpi_device_remove_notify_handler(acpi_dev);
1016                 if (acpi_drv->ops.remove)
1017                         acpi_drv->ops.remove(acpi_dev);
1018         }
1019         acpi_dev->driver = NULL;
1020         acpi_dev->driver_data = NULL;
1021 
1022         put_device(dev);
1023         return 0;
1024 }
1025 
1026 struct bus_type acpi_bus_type = {
1027         .name           = "acpi",
1028         .match          = acpi_bus_match,
1029         .probe          = acpi_device_probe,
1030         .remove         = acpi_device_remove,
1031         .uevent         = acpi_device_uevent,
1032 };
1033 
1034 static void acpi_device_del(struct acpi_device *device)
1035 {
1036         mutex_lock(&acpi_device_lock);
1037         if (device->parent)
1038                 list_del(&device->node);
1039 
1040         list_del(&device->wakeup_list);
1041         mutex_unlock(&acpi_device_lock);
1042 
1043         acpi_power_add_remove_device(device, false);
1044         acpi_device_remove_files(device);
1045         if (device->remove)
1046                 device->remove(device);
1047 
1048         device_del(&device->dev);
1049 }
1050 
1051 static LIST_HEAD(acpi_device_del_list);
1052 static DEFINE_MUTEX(acpi_device_del_lock);
1053 
1054 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
1055 {
1056         for (;;) {
1057                 struct acpi_device *adev;
1058 
1059                 mutex_lock(&acpi_device_del_lock);
1060 
1061                 if (list_empty(&acpi_device_del_list)) {
1062                         mutex_unlock(&acpi_device_del_lock);
1063                         break;
1064                 }
1065                 adev = list_first_entry(&acpi_device_del_list,
1066                                         struct acpi_device, del_list);
1067                 list_del(&adev->del_list);
1068 
1069                 mutex_unlock(&acpi_device_del_lock);
1070 
1071                 acpi_device_del(adev);
1072                 /*
1073                  * Drop references to all power resources that might have been
1074                  * used by the device.
1075                  */
1076                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1077                 put_device(&adev->dev);
1078         }
1079 }
1080 
1081 /**
1082  * acpi_scan_drop_device - Drop an ACPI device object.
1083  * @handle: Handle of an ACPI namespace node, not used.
1084  * @context: Address of the ACPI device object to drop.
1085  *
1086  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1087  * namespace node the device object pointed to by @context is attached to.
1088  *
1089  * The unregistration is carried out asynchronously to avoid running
1090  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1091  * ensure the correct ordering (the device objects must be unregistered in the
1092  * same order in which the corresponding namespace nodes are deleted).
1093  */
1094 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1095 {
1096         static DECLARE_WORK(work, acpi_device_del_work_fn);
1097         struct acpi_device *adev = context;
1098 
1099         mutex_lock(&acpi_device_del_lock);
1100 
1101         /*
1102          * Use the ACPI hotplug workqueue which is ordered, so this work item
1103          * won't run after any hotplug work items submitted subsequently.  That
1104          * prevents attempts to register device objects identical to those being
1105          * deleted from happening concurrently (such attempts result from
1106          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1107          * run after all of the work items submitted previosuly, which helps
1108          * those work items to ensure that they are not accessing stale device
1109          * objects.
1110          */
1111         if (list_empty(&acpi_device_del_list))
1112                 acpi_queue_hotplug_work(&work);
1113 
1114         list_add_tail(&adev->del_list, &acpi_device_del_list);
1115         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1116         adev->handle = INVALID_ACPI_HANDLE;
1117 
1118         mutex_unlock(&acpi_device_del_lock);
1119 }
1120 
1121 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
1122                                 void (*callback)(void *))
1123 {
1124         acpi_status status;
1125 
1126         if (!device)
1127                 return -EINVAL;
1128 
1129         status = acpi_get_data_full(handle, acpi_scan_drop_device,
1130                                     (void **)device, callback);
1131         if (ACPI_FAILURE(status) || !*device) {
1132                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1133                                   handle));
1134                 return -ENODEV;
1135         }
1136         return 0;
1137 }
1138 
1139 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1140 {
1141         return acpi_get_device_data(handle, device, NULL);
1142 }
1143 EXPORT_SYMBOL(acpi_bus_get_device);
1144 
1145 static void get_acpi_device(void *dev)
1146 {
1147         if (dev)
1148                 get_device(&((struct acpi_device *)dev)->dev);
1149 }
1150 
1151 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
1152 {
1153         struct acpi_device *adev = NULL;
1154 
1155         acpi_get_device_data(handle, &adev, get_acpi_device);
1156         return adev;
1157 }
1158 
1159 void acpi_bus_put_acpi_device(struct acpi_device *adev)
1160 {
1161         put_device(&adev->dev);
1162 }
1163 
1164 int acpi_device_add(struct acpi_device *device,
1165                     void (*release)(struct device *))
1166 {
1167         int result;
1168         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1169         int found = 0;
1170 
1171         if (device->handle) {
1172                 acpi_status status;
1173 
1174                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1175                                           device);
1176                 if (ACPI_FAILURE(status)) {
1177                         acpi_handle_err(device->handle,
1178                                         "Unable to attach device data\n");
1179                         return -ENODEV;
1180                 }
1181         }
1182 
1183         /*
1184          * Linkage
1185          * -------
1186          * Link this device to its parent and siblings.
1187          */
1188         INIT_LIST_HEAD(&device->children);
1189         INIT_LIST_HEAD(&device->node);
1190         INIT_LIST_HEAD(&device->wakeup_list);
1191         INIT_LIST_HEAD(&device->physical_node_list);
1192         INIT_LIST_HEAD(&device->del_list);
1193         mutex_init(&device->physical_node_lock);
1194 
1195         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1196         if (!new_bus_id) {
1197                 pr_err(PREFIX "Memory allocation error\n");
1198                 result = -ENOMEM;
1199                 goto err_detach;
1200         }
1201 
1202         mutex_lock(&acpi_device_lock);
1203         /*
1204          * Find suitable bus_id and instance number in acpi_bus_id_list
1205          * If failed, create one and link it into acpi_bus_id_list
1206          */
1207         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1208                 if (!strcmp(acpi_device_bus_id->bus_id,
1209                             acpi_device_hid(device))) {
1210                         acpi_device_bus_id->instance_no++;
1211                         found = 1;
1212                         kfree(new_bus_id);
1213                         break;
1214                 }
1215         }
1216         if (!found) {
1217                 acpi_device_bus_id = new_bus_id;
1218                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1219                 acpi_device_bus_id->instance_no = 0;
1220                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1221         }
1222         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1223 
1224         if (device->parent)
1225                 list_add_tail(&device->node, &device->parent->children);
1226 
1227         if (device->wakeup.flags.valid)
1228                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1229         mutex_unlock(&acpi_device_lock);
1230 
1231         if (device->parent)
1232                 device->dev.parent = &device->parent->dev;
1233         device->dev.bus = &acpi_bus_type;
1234         device->dev.release = release;
1235         result = device_add(&device->dev);
1236         if (result) {
1237                 dev_err(&device->dev, "Error registering device\n");
1238                 goto err;
1239         }
1240 
1241         result = acpi_device_setup_files(device);
1242         if (result)
1243                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1244                        dev_name(&device->dev));
1245 
1246         return 0;
1247 
1248  err:
1249         mutex_lock(&acpi_device_lock);
1250         if (device->parent)
1251                 list_del(&device->node);
1252         list_del(&device->wakeup_list);
1253         mutex_unlock(&acpi_device_lock);
1254 
1255  err_detach:
1256         acpi_detach_data(device->handle, acpi_scan_drop_device);
1257         return result;
1258 }
1259 
1260 /* --------------------------------------------------------------------------
1261                                  Driver Management
1262    -------------------------------------------------------------------------- */
1263 /**
1264  * acpi_bus_register_driver - register a driver with the ACPI bus
1265  * @driver: driver being registered
1266  *
1267  * Registers a driver with the ACPI bus.  Searches the namespace for all
1268  * devices that match the driver's criteria and binds.  Returns zero for
1269  * success or a negative error status for failure.
1270  */
1271 int acpi_bus_register_driver(struct acpi_driver *driver)
1272 {
1273         int ret;
1274 
1275         if (acpi_disabled)
1276                 return -ENODEV;
1277         driver->drv.name = driver->name;
1278         driver->drv.bus = &acpi_bus_type;
1279         driver->drv.owner = driver->owner;
1280 
1281         ret = driver_register(&driver->drv);
1282         return ret;
1283 }
1284 
1285 EXPORT_SYMBOL(acpi_bus_register_driver);
1286 
1287 /**
1288  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1289  * @driver: driver to unregister
1290  *
1291  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1292  * devices that match the driver's criteria and unbinds.
1293  */
1294 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1295 {
1296         driver_unregister(&driver->drv);
1297 }
1298 
1299 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1300 
1301 /* --------------------------------------------------------------------------
1302                                  Device Enumeration
1303    -------------------------------------------------------------------------- */
1304 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1305 {
1306         struct acpi_device *device = NULL;
1307         acpi_status status;
1308 
1309         /*
1310          * Fixed hardware devices do not appear in the namespace and do not
1311          * have handles, but we fabricate acpi_devices for them, so we have
1312          * to deal with them specially.
1313          */
1314         if (!handle)
1315                 return acpi_root;
1316 
1317         do {
1318                 status = acpi_get_parent(handle, &handle);
1319                 if (ACPI_FAILURE(status))
1320                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1321         } while (acpi_bus_get_device(handle, &device));
1322         return device;
1323 }
1324 
1325 acpi_status
1326 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1327 {
1328         acpi_status status;
1329         acpi_handle tmp;
1330         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1331         union acpi_object *obj;
1332 
1333         status = acpi_get_handle(handle, "_EJD", &tmp);
1334         if (ACPI_FAILURE(status))
1335                 return status;
1336 
1337         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1338         if (ACPI_SUCCESS(status)) {
1339                 obj = buffer.pointer;
1340                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1341                                          ejd);
1342                 kfree(buffer.pointer);
1343         }
1344         return status;
1345 }
1346 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1347 
1348 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1349                                         struct acpi_device_wakeup *wakeup)
1350 {
1351         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1352         union acpi_object *package = NULL;
1353         union acpi_object *element = NULL;
1354         acpi_status status;
1355         int err = -ENODATA;
1356 
1357         if (!wakeup)
1358                 return -EINVAL;
1359 
1360         INIT_LIST_HEAD(&wakeup->resources);
1361 
1362         /* _PRW */
1363         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1364         if (ACPI_FAILURE(status)) {
1365                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1366                 return err;
1367         }
1368 
1369         package = (union acpi_object *)buffer.pointer;
1370 
1371         if (!package || package->package.count < 2)
1372                 goto out;
1373 
1374         element = &(package->package.elements[0]);
1375         if (!element)
1376                 goto out;
1377 
1378         if (element->type == ACPI_TYPE_PACKAGE) {
1379                 if ((element->package.count < 2) ||
1380                     (element->package.elements[0].type !=
1381                      ACPI_TYPE_LOCAL_REFERENCE)
1382                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1383                         goto out;
1384 
1385                 wakeup->gpe_device =
1386                     element->package.elements[0].reference.handle;
1387                 wakeup->gpe_number =
1388                     (u32) element->package.elements[1].integer.value;
1389         } else if (element->type == ACPI_TYPE_INTEGER) {
1390                 wakeup->gpe_device = NULL;
1391                 wakeup->gpe_number = element->integer.value;
1392         } else {
1393                 goto out;
1394         }
1395 
1396         element = &(package->package.elements[1]);
1397         if (element->type != ACPI_TYPE_INTEGER)
1398                 goto out;
1399 
1400         wakeup->sleep_state = element->integer.value;
1401 
1402         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1403         if (err)
1404                 goto out;
1405 
1406         if (!list_empty(&wakeup->resources)) {
1407                 int sleep_state;
1408 
1409                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1410                                                   &sleep_state);
1411                 if (err) {
1412                         acpi_handle_warn(handle, "Retrieving current states "
1413                                          "of wakeup power resources failed\n");
1414                         acpi_power_resources_list_free(&wakeup->resources);
1415                         goto out;
1416                 }
1417                 if (sleep_state < wakeup->sleep_state) {
1418                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1419                                          "(S%d) by S%d from power resources\n",
1420                                          (int)wakeup->sleep_state, sleep_state);
1421                         wakeup->sleep_state = sleep_state;
1422                 }
1423         }
1424         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1425 
1426  out:
1427         kfree(buffer.pointer);
1428         return err;
1429 }
1430 
1431 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1432 {
1433         struct acpi_device_id button_device_ids[] = {
1434                 {"PNP0C0C", 0},
1435                 {"PNP0C0D", 0},
1436                 {"PNP0C0E", 0},
1437                 {"", 0},
1438         };
1439         acpi_status status;
1440         acpi_event_status event_status;
1441 
1442         device->wakeup.flags.notifier_present = 0;
1443 
1444         /* Power button, Lid switch always enable wakeup */
1445         if (!acpi_match_device_ids(device, button_device_ids)) {
1446                 device->wakeup.flags.run_wake = 1;
1447                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1448                         /* Do not use Lid/sleep button for S5 wakeup */
1449                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1450                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1451                 }
1452                 device_set_wakeup_capable(&device->dev, true);
1453                 return;
1454         }
1455 
1456         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1457                                         device->wakeup.gpe_number,
1458                                                 &event_status);
1459         if (status == AE_OK)
1460                 device->wakeup.flags.run_wake =
1461                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1462 }
1463 
1464 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1465 {
1466         int err;
1467 
1468         /* Presence of _PRW indicates wake capable */
1469         if (!acpi_has_method(device->handle, "_PRW"))
1470                 return;
1471 
1472         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1473                                                            &device->wakeup);
1474         if (err) {
1475                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1476                 return;
1477         }
1478 
1479         device->wakeup.flags.valid = 1;
1480         device->wakeup.prepare_count = 0;
1481         acpi_bus_set_run_wake_flags(device);
1482         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1483          * system for the ACPI device with the _PRW object.
1484          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1485          * So it is necessary to call _DSW object first. Only when it is not
1486          * present will the _PSW object used.
1487          */
1488         err = acpi_device_sleep_wake(device, 0, 0, 0);
1489         if (err)
1490                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1491                                 "error in _DSW or _PSW evaluation\n"));
1492 }
1493 
1494 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1495 {
1496         struct acpi_device_power_state *ps = &device->power.states[state];
1497         char pathname[5] = { '_', 'P', 'R', '' + state, '\0' };
1498         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1499         acpi_status status;
1500 
1501         INIT_LIST_HEAD(&ps->resources);
1502 
1503         /* Evaluate "_PRx" to get referenced power resources */
1504         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1505         if (ACPI_SUCCESS(status)) {
1506                 union acpi_object *package = buffer.pointer;
1507 
1508                 if (buffer.length && package
1509                     && package->type == ACPI_TYPE_PACKAGE
1510                     && package->package.count) {
1511                         int err = acpi_extract_power_resources(package, 0,
1512                                                                &ps->resources);
1513                         if (!err)
1514                                 device->power.flags.power_resources = 1;
1515                 }
1516                 ACPI_FREE(buffer.pointer);
1517         }
1518 
1519         /* Evaluate "_PSx" to see if we can do explicit sets */
1520         pathname[2] = 'S';
1521         if (acpi_has_method(device->handle, pathname))
1522                 ps->flags.explicit_set = 1;
1523 
1524         /*
1525          * State is valid if there are means to put the device into it.
1526          * D3hot is only valid if _PR3 present.
1527          */
1528         if (!list_empty(&ps->resources)
1529             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1530                 ps->flags.valid = 1;
1531                 ps->flags.os_accessible = 1;
1532         }
1533 
1534         ps->power = -1;         /* Unknown - driver assigned */
1535         ps->latency = -1;       /* Unknown - driver assigned */
1536 }
1537 
1538 static void acpi_bus_get_power_flags(struct acpi_device *device)
1539 {
1540         u32 i;
1541 
1542         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1543         if (!acpi_has_method(device->handle, "_PS0") &&
1544             !acpi_has_method(device->handle, "_PR0"))
1545                 return;
1546 
1547         device->flags.power_manageable = 1;
1548 
1549         /*
1550          * Power Management Flags
1551          */
1552         if (acpi_has_method(device->handle, "_PSC"))
1553                 device->power.flags.explicit_get = 1;
1554 
1555         if (acpi_has_method(device->handle, "_IRC"))
1556                 device->power.flags.inrush_current = 1;
1557 
1558         if (acpi_has_method(device->handle, "_DSW"))
1559                 device->power.flags.dsw_present = 1;
1560 
1561         /*
1562          * Enumerate supported power management states
1563          */
1564         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1565                 acpi_bus_init_power_state(device, i);
1566 
1567         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1568 
1569         /* Set defaults for D0 and D3 states (always valid) */
1570         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1571         device->power.states[ACPI_STATE_D0].power = 100;
1572         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1573         device->power.states[ACPI_STATE_D3_COLD].power = 0;
1574 
1575         /* Set D3cold's explicit_set flag if _PS3 exists. */
1576         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1577                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1578 
1579         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1580         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1581                         device->power.flags.power_resources)
1582                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1583 
1584         if (acpi_bus_init_power(device)) {
1585                 acpi_free_power_resources_lists(device);
1586                 device->flags.power_manageable = 0;
1587         }
1588 }
1589 
1590 static void acpi_bus_get_flags(struct acpi_device *device)
1591 {
1592         /* Presence of _STA indicates 'dynamic_status' */
1593         if (acpi_has_method(device->handle, "_STA"))
1594                 device->flags.dynamic_status = 1;
1595 
1596         /* Presence of _RMV indicates 'removable' */
1597         if (acpi_has_method(device->handle, "_RMV"))
1598                 device->flags.removable = 1;
1599 
1600         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1601         if (acpi_has_method(device->handle, "_EJD") ||
1602             acpi_has_method(device->handle, "_EJ0"))
1603                 device->flags.ejectable = 1;
1604 }
1605 
1606 static void acpi_device_get_busid(struct acpi_device *device)
1607 {
1608         char bus_id[5] = { '?', 0 };
1609         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1610         int i = 0;
1611 
1612         /*
1613          * Bus ID
1614          * ------
1615          * The device's Bus ID is simply the object name.
1616          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1617          */
1618         if (ACPI_IS_ROOT_DEVICE(device)) {
1619                 strcpy(device->pnp.bus_id, "ACPI");
1620                 return;
1621         }
1622 
1623         switch (device->device_type) {
1624         case ACPI_BUS_TYPE_POWER_BUTTON:
1625                 strcpy(device->pnp.bus_id, "PWRF");
1626                 break;
1627         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1628                 strcpy(device->pnp.bus_id, "SLPF");
1629                 break;
1630         default:
1631                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1632                 /* Clean up trailing underscores (if any) */
1633                 for (i = 3; i > 1; i--) {
1634                         if (bus_id[i] == '_')
1635                                 bus_id[i] = '\0';
1636                         else
1637                                 break;
1638                 }
1639                 strcpy(device->pnp.bus_id, bus_id);
1640                 break;
1641         }
1642 }
1643 
1644 /*
1645  * acpi_ata_match - see if an acpi object is an ATA device
1646  *
1647  * If an acpi object has one of the ACPI ATA methods defined,
1648  * then we can safely call it an ATA device.
1649  */
1650 bool acpi_ata_match(acpi_handle handle)
1651 {
1652         return acpi_has_method(handle, "_GTF") ||
1653                acpi_has_method(handle, "_GTM") ||
1654                acpi_has_method(handle, "_STM") ||
1655                acpi_has_method(handle, "_SDD");
1656 }
1657 
1658 /*
1659  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1660  *
1661  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1662  * then we can safely call it an ejectable drive bay
1663  */
1664 bool acpi_bay_match(acpi_handle handle)
1665 {
1666         acpi_handle phandle;
1667 
1668         if (!acpi_has_method(handle, "_EJ0"))
1669                 return false;
1670         if (acpi_ata_match(handle))
1671                 return true;
1672         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1673                 return false;
1674 
1675         return acpi_ata_match(phandle);
1676 }
1677 
1678 bool acpi_device_is_battery(struct acpi_device *adev)
1679 {
1680         struct acpi_hardware_id *hwid;
1681 
1682         list_for_each_entry(hwid, &adev->pnp.ids, list)
1683                 if (!strcmp("PNP0C0A", hwid->id))
1684                         return true;
1685 
1686         return false;
1687 }
1688 
1689 static bool is_ejectable_bay(struct acpi_device *adev)
1690 {
1691         acpi_handle handle = adev->handle;
1692 
1693         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1694                 return true;
1695 
1696         return acpi_bay_match(handle);
1697 }
1698 
1699 /*
1700  * acpi_dock_match - see if an acpi object has a _DCK method
1701  */
1702 bool acpi_dock_match(acpi_handle handle)
1703 {
1704         return acpi_has_method(handle, "_DCK");
1705 }
1706 
1707 const char *acpi_device_hid(struct acpi_device *device)
1708 {
1709         struct acpi_hardware_id *hid;
1710 
1711         if (list_empty(&device->pnp.ids))
1712                 return dummy_hid;
1713 
1714         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1715         return hid->id;
1716 }
1717 EXPORT_SYMBOL(acpi_device_hid);
1718 
1719 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1720 {
1721         struct acpi_hardware_id *id;
1722 
1723         id = kmalloc(sizeof(*id), GFP_KERNEL);
1724         if (!id)
1725                 return;
1726 
1727         id->id = kstrdup(dev_id, GFP_KERNEL);
1728         if (!id->id) {
1729                 kfree(id);
1730                 return;
1731         }
1732 
1733         list_add_tail(&id->list, &pnp->ids);
1734         pnp->type.hardware_id = 1;
1735 }
1736 
1737 /*
1738  * Old IBM workstations have a DSDT bug wherein the SMBus object
1739  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1740  * prefix.  Work around this.
1741  */
1742 static bool acpi_ibm_smbus_match(acpi_handle handle)
1743 {
1744         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1745         struct acpi_buffer path = { sizeof(node_name), node_name };
1746 
1747         if (!dmi_name_in_vendors("IBM"))
1748                 return false;
1749 
1750         /* Look for SMBS object */
1751         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1752             strcmp("SMBS", path.pointer))
1753                 return false;
1754 
1755         /* Does it have the necessary (but misnamed) methods? */
1756         if (acpi_has_method(handle, "SBI") &&
1757             acpi_has_method(handle, "SBR") &&
1758             acpi_has_method(handle, "SBW"))
1759                 return true;
1760 
1761         return false;
1762 }
1763 
1764 static bool acpi_object_is_system_bus(acpi_handle handle)
1765 {
1766         acpi_handle tmp;
1767 
1768         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1769             tmp == handle)
1770                 return true;
1771         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1772             tmp == handle)
1773                 return true;
1774 
1775         return false;
1776 }
1777 
1778 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1779                                 int device_type)
1780 {
1781         acpi_status status;
1782         struct acpi_device_info *info;
1783         struct acpi_pnp_device_id_list *cid_list;
1784         int i;
1785 
1786         switch (device_type) {
1787         case ACPI_BUS_TYPE_DEVICE:
1788                 if (handle == ACPI_ROOT_OBJECT) {
1789                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1790                         break;
1791                 }
1792 
1793                 status = acpi_get_object_info(handle, &info);
1794                 if (ACPI_FAILURE(status)) {
1795                         pr_err(PREFIX "%s: Error reading device info\n",
1796                                         __func__);
1797                         return;
1798                 }
1799 
1800                 if (info->valid & ACPI_VALID_HID) {
1801                         acpi_add_id(pnp, info->hardware_id.string);
1802                         pnp->type.platform_id = 1;
1803                 }
1804                 if (info->valid & ACPI_VALID_CID) {
1805                         cid_list = &info->compatible_id_list;
1806                         for (i = 0; i < cid_list->count; i++)
1807                                 acpi_add_id(pnp, cid_list->ids[i].string);
1808                 }
1809                 if (info->valid & ACPI_VALID_ADR) {
1810                         pnp->bus_address = info->address;
1811                         pnp->type.bus_address = 1;
1812                 }
1813                 if (info->valid & ACPI_VALID_UID)
1814                         pnp->unique_id = kstrdup(info->unique_id.string,
1815                                                         GFP_KERNEL);
1816 
1817                 kfree(info);
1818 
1819                 /*
1820                  * Some devices don't reliably have _HIDs & _CIDs, so add
1821                  * synthetic HIDs to make sure drivers can find them.
1822                  */
1823                 if (acpi_is_video_device(handle))
1824                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1825                 else if (acpi_bay_match(handle))
1826                         acpi_add_id(pnp, ACPI_BAY_HID);
1827                 else if (acpi_dock_match(handle))
1828                         acpi_add_id(pnp, ACPI_DOCK_HID);
1829                 else if (acpi_ibm_smbus_match(handle))
1830                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1831                 else if (list_empty(&pnp->ids) &&
1832                          acpi_object_is_system_bus(handle)) {
1833                         /* \_SB, \_TZ, LNXSYBUS */
1834                         acpi_add_id(pnp, ACPI_BUS_HID);
1835                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1836                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1837                 }
1838 
1839                 break;
1840         case ACPI_BUS_TYPE_POWER:
1841                 acpi_add_id(pnp, ACPI_POWER_HID);
1842                 break;
1843         case ACPI_BUS_TYPE_PROCESSOR:
1844                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1845                 break;
1846         case ACPI_BUS_TYPE_THERMAL:
1847                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1848                 break;
1849         case ACPI_BUS_TYPE_POWER_BUTTON:
1850                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1851                 break;
1852         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1853                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1854                 break;
1855         }
1856 }
1857 
1858 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1859 {
1860         struct acpi_hardware_id *id, *tmp;
1861 
1862         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1863                 kfree(id->id);
1864                 kfree(id);
1865         }
1866         kfree(pnp->unique_id);
1867 }
1868 
1869 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1870                              int type, unsigned long long sta)
1871 {
1872         INIT_LIST_HEAD(&device->pnp.ids);
1873         device->device_type = type;
1874         device->handle = handle;
1875         device->parent = acpi_bus_get_parent(handle);
1876         acpi_set_device_status(device, sta);
1877         acpi_device_get_busid(device);
1878         acpi_set_pnp_ids(handle, &device->pnp, type);
1879         acpi_bus_get_flags(device);
1880         device->flags.match_driver = false;
1881         device->flags.initialized = true;
1882         device->flags.visited = false;
1883         device_initialize(&device->dev);
1884         dev_set_uevent_suppress(&device->dev, true);
1885 }
1886 
1887 void acpi_device_add_finalize(struct acpi_device *device)
1888 {
1889         dev_set_uevent_suppress(&device->dev, false);
1890         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1891 }
1892 
1893 static int acpi_add_single_object(struct acpi_device **child,
1894                                   acpi_handle handle, int type,
1895                                   unsigned long long sta)
1896 {
1897         int result;
1898         struct acpi_device *device;
1899         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1900 
1901         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1902         if (!device) {
1903                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1904                 return -ENOMEM;
1905         }
1906 
1907         acpi_init_device_object(device, handle, type, sta);
1908         acpi_bus_get_power_flags(device);
1909         acpi_bus_get_wakeup_device_flags(device);
1910 
1911         result = acpi_device_add(device, acpi_device_release);
1912         if (result) {
1913                 acpi_device_release(&device->dev);
1914                 return result;
1915         }
1916 
1917         acpi_power_add_remove_device(device, true);
1918         acpi_device_add_finalize(device);
1919         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1920         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1921                 dev_name(&device->dev), (char *) buffer.pointer,
1922                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1923         kfree(buffer.pointer);
1924         *child = device;
1925         return 0;
1926 }
1927 
1928 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1929                                     unsigned long long *sta)
1930 {
1931         acpi_status status;
1932         acpi_object_type acpi_type;
1933 
1934         status = acpi_get_type(handle, &acpi_type);
1935         if (ACPI_FAILURE(status))
1936                 return -ENODEV;
1937 
1938         switch (acpi_type) {
1939         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1940         case ACPI_TYPE_DEVICE:
1941                 *type = ACPI_BUS_TYPE_DEVICE;
1942                 status = acpi_bus_get_status_handle(handle, sta);
1943                 if (ACPI_FAILURE(status))
1944                         return -ENODEV;
1945                 break;
1946         case ACPI_TYPE_PROCESSOR:
1947                 *type = ACPI_BUS_TYPE_PROCESSOR;
1948                 status = acpi_bus_get_status_handle(handle, sta);
1949                 if (ACPI_FAILURE(status))
1950                         return -ENODEV;
1951                 break;
1952         case ACPI_TYPE_THERMAL:
1953                 *type = ACPI_BUS_TYPE_THERMAL;
1954                 *sta = ACPI_STA_DEFAULT;
1955                 break;
1956         case ACPI_TYPE_POWER:
1957                 *type = ACPI_BUS_TYPE_POWER;
1958                 *sta = ACPI_STA_DEFAULT;
1959                 break;
1960         default:
1961                 return -ENODEV;
1962         }
1963 
1964         return 0;
1965 }
1966 
1967 bool acpi_device_is_present(struct acpi_device *adev)
1968 {
1969         if (adev->status.present || adev->status.functional)
1970                 return true;
1971 
1972         adev->flags.initialized = false;
1973         return false;
1974 }
1975 
1976 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1977                                        char *idstr,
1978                                        const struct acpi_device_id **matchid)
1979 {
1980         const struct acpi_device_id *devid;
1981 
1982         if (handler->match)
1983                 return handler->match(idstr, matchid);
1984 
1985         for (devid = handler->ids; devid->id[0]; devid++)
1986                 if (!strcmp((char *)devid->id, idstr)) {
1987                         if (matchid)
1988                                 *matchid = devid;
1989 
1990                         return true;
1991                 }
1992 
1993         return false;
1994 }
1995 
1996 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1997                                         const struct acpi_device_id **matchid)
1998 {
1999         struct acpi_scan_handler *handler;
2000 
2001         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
2002                 if (acpi_scan_handler_matching(handler, idstr, matchid))
2003                         return handler;
2004 
2005         return NULL;
2006 }
2007 
2008 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
2009 {
2010         if (!!hotplug->enabled == !!val)
2011                 return;
2012 
2013         mutex_lock(&acpi_scan_lock);
2014 
2015         hotplug->enabled = val;
2016 
2017         mutex_unlock(&acpi_scan_lock);
2018 }
2019 
2020 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2021 {
2022         struct acpi_hardware_id *hwid;
2023 
2024         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2025                 acpi_dock_add(adev);
2026                 return;
2027         }
2028         list_for_each_entry(hwid, &adev->pnp.ids, list) {
2029                 struct acpi_scan_handler *handler;
2030 
2031                 handler = acpi_scan_match_handler(hwid->id, NULL);
2032                 if (handler) {
2033                         adev->flags.hotplug_notify = true;
2034                         break;
2035                 }
2036         }
2037 }
2038 
2039 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
2040                                       void *not_used, void **return_value)
2041 {
2042         struct acpi_device *device = NULL;
2043         int type;
2044         unsigned long long sta;
2045         int result;
2046 
2047         acpi_bus_get_device(handle, &device);
2048         if (device)
2049                 goto out;
2050 
2051         result = acpi_bus_type_and_status(handle, &type, &sta);
2052         if (result)
2053                 return AE_OK;
2054 
2055         if (type == ACPI_BUS_TYPE_POWER) {
2056                 acpi_add_power_resource(handle);
2057                 return AE_OK;
2058         }
2059 
2060         acpi_add_single_object(&device, handle, type, sta);
2061         if (!device)
2062                 return AE_CTRL_DEPTH;
2063 
2064         acpi_scan_init_hotplug(device);
2065 
2066  out:
2067         if (!*return_value)
2068                 *return_value = device;
2069 
2070         return AE_OK;
2071 }
2072 
2073 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
2074 {
2075         bool *is_spi_i2c_slave_p = data;
2076 
2077         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
2078                 return 1;
2079 
2080         /*
2081          * devices that are connected to UART still need to be enumerated to
2082          * platform bus
2083          */
2084         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
2085                 *is_spi_i2c_slave_p = true;
2086 
2087          /* no need to do more checking */
2088         return -1;
2089 }
2090 
2091 static void acpi_default_enumeration(struct acpi_device *device)
2092 {
2093         struct list_head resource_list;
2094         bool is_spi_i2c_slave = false;
2095 
2096         if (!device->pnp.type.platform_id || device->handler)
2097                 return;
2098 
2099         /*
2100          * Do not enemerate SPI/I2C slaves as they will be enuerated by their
2101          * respective parents.
2102          */
2103         INIT_LIST_HEAD(&resource_list);
2104         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
2105                                &is_spi_i2c_slave);
2106         acpi_dev_free_resource_list(&resource_list);
2107         if (!is_spi_i2c_slave)
2108                 acpi_create_platform_device(device);
2109 }
2110 
2111 static int acpi_scan_attach_handler(struct acpi_device *device)
2112 {
2113         struct acpi_hardware_id *hwid;
2114         int ret = 0;
2115 
2116         list_for_each_entry(hwid, &device->pnp.ids, list) {
2117                 const struct acpi_device_id *devid;
2118                 struct acpi_scan_handler *handler;
2119 
2120                 handler = acpi_scan_match_handler(hwid->id, &devid);
2121                 if (handler) {
2122                         if (!handler->attach) {
2123                                 device->pnp.type.platform_id = 0;
2124                                 continue;
2125                         }
2126                         device->handler = handler;
2127                         ret = handler->attach(device, devid);
2128                         if (ret > 0)
2129                                 break;
2130 
2131                         device->handler = NULL;
2132                         if (ret < 0)
2133                                 break;
2134                 }
2135         }
2136         if (!ret)
2137                 acpi_default_enumeration(device);
2138 
2139         return ret;
2140 }
2141 
2142 static void acpi_bus_attach(struct acpi_device *device)
2143 {
2144         struct acpi_device *child;
2145         acpi_handle ejd;
2146         int ret;
2147 
2148         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2149                 register_dock_dependent_device(device, ejd);
2150 
2151         acpi_bus_get_status(device);
2152         /* Skip devices that are not present. */
2153         if (!acpi_device_is_present(device)) {
2154                 device->flags.visited = false;
2155                 return;
2156         }
2157         if (device->handler)
2158                 goto ok;
2159 
2160         if (!device->flags.initialized) {
2161                 acpi_bus_update_power(device, NULL);
2162                 device->flags.initialized = true;
2163         }
2164         device->flags.visited = false;
2165         ret = acpi_scan_attach_handler(device);
2166         if (ret < 0)
2167                 return;
2168 
2169         device->flags.match_driver = true;
2170         if (!ret) {
2171                 ret = device_attach(&device->dev);
2172                 if (ret < 0)
2173                         return;
2174         }
2175         device->flags.visited = true;
2176 
2177  ok:
2178         list_for_each_entry(child, &device->children, node)
2179                 acpi_bus_attach(child);
2180 }
2181 
2182 /**
2183  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2184  * @handle: Root of the namespace scope to scan.
2185  *
2186  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2187  * found devices.
2188  *
2189  * If no devices were found, -ENODEV is returned, but it does not mean that
2190  * there has been a real error.  There just have been no suitable ACPI objects
2191  * in the table trunk from which the kernel could create a device and add an
2192  * appropriate driver.
2193  *
2194  * Must be called under acpi_scan_lock.
2195  */
2196 int acpi_bus_scan(acpi_handle handle)
2197 {
2198         void *device = NULL;
2199 
2200         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2201                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2202                                     acpi_bus_check_add, NULL, NULL, &device);
2203 
2204         if (device) {
2205                 acpi_bus_attach(device);
2206                 return 0;
2207         }
2208         return -ENODEV;
2209 }
2210 EXPORT_SYMBOL(acpi_bus_scan);
2211 
2212 /**
2213  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2214  * @adev: Root of the ACPI namespace scope to walk.
2215  *
2216  * Must be called under acpi_scan_lock.
2217  */
2218 void acpi_bus_trim(struct acpi_device *adev)
2219 {
2220         struct acpi_scan_handler *handler = adev->handler;
2221         struct acpi_device *child;
2222 
2223         list_for_each_entry_reverse(child, &adev->children, node)
2224                 acpi_bus_trim(child);
2225 
2226         adev->flags.match_driver = false;
2227         if (handler) {
2228                 if (handler->detach)
2229                         handler->detach(adev);
2230 
2231                 adev->handler = NULL;
2232         } else {
2233                 device_release_driver(&adev->dev);
2234         }
2235         /*
2236          * Most likely, the device is going away, so put it into D3cold before
2237          * that.
2238          */
2239         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2240         adev->flags.initialized = false;
2241         adev->flags.visited = false;
2242 }
2243 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2244 
2245 static int acpi_bus_scan_fixed(void)
2246 {
2247         int result = 0;
2248 
2249         /*
2250          * Enumerate all fixed-feature devices.
2251          */
2252         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2253                 struct acpi_device *device = NULL;
2254 
2255                 result = acpi_add_single_object(&device, NULL,
2256                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2257                                                 ACPI_STA_DEFAULT);
2258                 if (result)
2259                         return result;
2260 
2261                 device->flags.match_driver = true;
2262                 result = device_attach(&device->dev);
2263                 if (result < 0)
2264                         return result;
2265 
2266                 device_init_wakeup(&device->dev, true);
2267         }
2268 
2269         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2270                 struct acpi_device *device = NULL;
2271 
2272                 result = acpi_add_single_object(&device, NULL,
2273                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2274                                                 ACPI_STA_DEFAULT);
2275                 if (result)
2276                         return result;
2277 
2278                 device->flags.match_driver = true;
2279                 result = device_attach(&device->dev);
2280         }
2281 
2282         return result < 0 ? result : 0;
2283 }
2284 
2285 int __init acpi_scan_init(void)
2286 {
2287         int result;
2288 
2289         result = bus_register(&acpi_bus_type);
2290         if (result) {
2291                 /* We don't want to quit even if we failed to add suspend/resume */
2292                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2293         }
2294 
2295         acpi_pci_root_init();
2296         acpi_pci_link_init();
2297         acpi_processor_init();
2298         acpi_lpss_init();
2299         acpi_cmos_rtc_init();
2300         acpi_container_init();
2301         acpi_memory_hotplug_init();
2302         acpi_pnp_init();
2303 
2304         mutex_lock(&acpi_scan_lock);
2305         /*
2306          * Enumerate devices in the ACPI namespace.
2307          */
2308         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2309         if (result)
2310                 goto out;
2311 
2312         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2313         if (result)
2314                 goto out;
2315 
2316         /* Fixed feature devices do not exist on HW-reduced platform */
2317         if (!acpi_gbl_reduced_hardware) {
2318                 result = acpi_bus_scan_fixed();
2319                 if (result) {
2320                         acpi_detach_data(acpi_root->handle,
2321                                          acpi_scan_drop_device);
2322                         acpi_device_del(acpi_root);
2323                         put_device(&acpi_root->dev);
2324                         goto out;
2325                 }
2326         }
2327 
2328         acpi_update_all_gpes();
2329 
2330  out:
2331         mutex_unlock(&acpi_scan_lock);
2332         return result;
2333 }
2334 

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