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[linux-2.6.git] / drivers / acpi / scan.c
1 /*
2  * scan.c - support for transforming the ACPI namespace into individual objects
3  */
4
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/acpi.h>
9 #include <linux/signal.h>
10 #include <linux/kthread.h>
11
12 #include <acpi/acpi_drivers.h>
13
14 #include "internal.h"
15
16 #define _COMPONENT              ACPI_BUS_COMPONENT
17 ACPI_MODULE_NAME("scan");
18 #define STRUCT_TO_INT(s)        (*((int*)&s))
19 extern struct acpi_device *acpi_root;
20
21 #define ACPI_BUS_CLASS                  "system_bus"
22 #define ACPI_BUS_HID                    "LNXSYBUS"
23 #define ACPI_BUS_DEVICE_NAME            "System Bus"
24
25 static LIST_HEAD(acpi_device_list);
26 static LIST_HEAD(acpi_bus_id_list);
27 DEFINE_MUTEX(acpi_device_lock);
28 LIST_HEAD(acpi_wakeup_device_list);
29
30 struct acpi_device_bus_id{
31         char bus_id[15];
32         unsigned int instance_no;
33         struct list_head node;
34 };
35
36 /*
37  * Creates hid/cid(s) string needed for modalias and uevent
38  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
39  * char *modalias: "acpi:IBM0001:ACPI0001"
40 */
41 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
42                            int size)
43 {
44         int len;
45         int count;
46
47         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
48                 return -ENODEV;
49
50         len = snprintf(modalias, size, "acpi:");
51         size -= len;
52
53         if (acpi_dev->flags.hardware_id) {
54                 count = snprintf(&modalias[len], size, "%s:",
55                                  acpi_dev->pnp.hardware_id);
56                 if (count < 0 || count >= size)
57                         return -EINVAL;
58                 len += count;
59                 size -= count;
60         }
61
62         if (acpi_dev->flags.compatible_ids) {
63                 struct acpi_compatible_id_list *cid_list;
64                 int i;
65
66                 cid_list = acpi_dev->pnp.cid_list;
67                 for (i = 0; i < cid_list->count; i++) {
68                         count = snprintf(&modalias[len], size, "%s:",
69                                          cid_list->id[i].value);
70                         if (count < 0 || count >= size) {
71                                 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
72                                        acpi_dev->pnp.device_name, i);
73                                 break;
74                         }
75                         len += count;
76                         size -= count;
77                 }
78         }
79
80         modalias[len] = '\0';
81         return len;
82 }
83
84 static ssize_t
85 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
86         struct acpi_device *acpi_dev = to_acpi_device(dev);
87         int len;
88
89         /* Device has no HID and no CID or string is >1024 */
90         len = create_modalias(acpi_dev, buf, 1024);
91         if (len <= 0)
92                 return 0;
93         buf[len++] = '\n';
94         return len;
95 }
96 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
97
98 static void acpi_bus_hot_remove_device(void *context)
99 {
100         struct acpi_device *device;
101         acpi_handle handle = context;
102         struct acpi_object_list arg_list;
103         union acpi_object arg;
104         acpi_status status = AE_OK;
105
106         if (acpi_bus_get_device(handle, &device))
107                 return;
108
109         if (!device)
110                 return;
111
112         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
113                 "Hot-removing device %s...\n", dev_name(&device->dev)));
114
115         if (acpi_bus_trim(device, 1)) {
116                 printk(KERN_ERR PREFIX
117                                 "Removing device failed\n");
118                 return;
119         }
120
121         /* power off device */
122         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
123         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
124                 printk(KERN_WARNING PREFIX
125                                 "Power-off device failed\n");
126
127         if (device->flags.lockable) {
128                 arg_list.count = 1;
129                 arg_list.pointer = &arg;
130                 arg.type = ACPI_TYPE_INTEGER;
131                 arg.integer.value = 0;
132                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
133         }
134
135         arg_list.count = 1;
136         arg_list.pointer = &arg;
137         arg.type = ACPI_TYPE_INTEGER;
138         arg.integer.value = 1;
139
140         /*
141          * TBD: _EJD support.
142          */
143         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
144         if (ACPI_FAILURE(status))
145                 printk(KERN_WARNING PREFIX
146                                 "Eject device failed\n");
147
148         return;
149 }
150
151 static ssize_t
152 acpi_eject_store(struct device *d, struct device_attribute *attr,
153                 const char *buf, size_t count)
154 {
155         int ret = count;
156         acpi_status status;
157         acpi_object_type type = 0;
158         struct acpi_device *acpi_device = to_acpi_device(d);
159
160         if ((!count) || (buf[0] != '1')) {
161                 return -EINVAL;
162         }
163 #ifndef FORCE_EJECT
164         if (acpi_device->driver == NULL) {
165                 ret = -ENODEV;
166                 goto err;
167         }
168 #endif
169         status = acpi_get_type(acpi_device->handle, &type);
170         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
171                 ret = -ENODEV;
172                 goto err;
173         }
174
175         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
176 err:
177         return ret;
178 }
179
180 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
181
182 static ssize_t
183 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
184         struct acpi_device *acpi_dev = to_acpi_device(dev);
185
186         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
187 }
188 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
189
190 static ssize_t
191 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
192         struct acpi_device *acpi_dev = to_acpi_device(dev);
193         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
194         int result;
195
196         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
197         if (result)
198                 goto end;
199
200         result = sprintf(buf, "%s\n", (char*)path.pointer);
201         kfree(path.pointer);
202 end:
203         return result;
204 }
205 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
206
207 static int acpi_device_setup_files(struct acpi_device *dev)
208 {
209         acpi_status status;
210         acpi_handle temp;
211         int result = 0;
212
213         /*
214          * Devices gotten from FADT don't have a "path" attribute
215          */
216         if (dev->handle) {
217                 result = device_create_file(&dev->dev, &dev_attr_path);
218                 if (result)
219                         goto end;
220         }
221
222         if (dev->flags.hardware_id) {
223                 result = device_create_file(&dev->dev, &dev_attr_hid);
224                 if (result)
225                         goto end;
226         }
227
228         if (dev->flags.hardware_id || dev->flags.compatible_ids) {
229                 result = device_create_file(&dev->dev, &dev_attr_modalias);
230                 if (result)
231                         goto end;
232         }
233
234         /*
235          * If device has _EJ0, 'eject' file is created that is used to trigger
236          * hot-removal function from userland.
237          */
238         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
239         if (ACPI_SUCCESS(status))
240                 result = device_create_file(&dev->dev, &dev_attr_eject);
241 end:
242         return result;
243 }
244
245 static void acpi_device_remove_files(struct acpi_device *dev)
246 {
247         acpi_status status;
248         acpi_handle temp;
249
250         /*
251          * If device has _EJ0, 'eject' file is created that is used to trigger
252          * hot-removal function from userland.
253          */
254         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
255         if (ACPI_SUCCESS(status))
256                 device_remove_file(&dev->dev, &dev_attr_eject);
257
258         if (dev->flags.hardware_id || dev->flags.compatible_ids)
259                 device_remove_file(&dev->dev, &dev_attr_modalias);
260
261         if (dev->flags.hardware_id)
262                 device_remove_file(&dev->dev, &dev_attr_hid);
263         if (dev->handle)
264                 device_remove_file(&dev->dev, &dev_attr_path);
265 }
266 /* --------------------------------------------------------------------------
267                         ACPI Bus operations
268    -------------------------------------------------------------------------- */
269
270 int acpi_match_device_ids(struct acpi_device *device,
271                           const struct acpi_device_id *ids)
272 {
273         const struct acpi_device_id *id;
274
275         /*
276          * If the device is not present, it is unnecessary to load device
277          * driver for it.
278          */
279         if (!device->status.present)
280                 return -ENODEV;
281
282         if (device->flags.hardware_id) {
283                 for (id = ids; id->id[0]; id++) {
284                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
285                                 return 0;
286                 }
287         }
288
289         if (device->flags.compatible_ids) {
290                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
291                 int i;
292
293                 for (id = ids; id->id[0]; id++) {
294                         /* compare multiple _CID entries against driver ids */
295                         for (i = 0; i < cid_list->count; i++) {
296                                 if (!strcmp((char*)id->id,
297                                             cid_list->id[i].value))
298                                         return 0;
299                         }
300                 }
301         }
302
303         return -ENOENT;
304 }
305 EXPORT_SYMBOL(acpi_match_device_ids);
306
307 static void acpi_device_release(struct device *dev)
308 {
309         struct acpi_device *acpi_dev = to_acpi_device(dev);
310
311         kfree(acpi_dev->pnp.cid_list);
312         kfree(acpi_dev);
313 }
314
315 static int acpi_device_suspend(struct device *dev, pm_message_t state)
316 {
317         struct acpi_device *acpi_dev = to_acpi_device(dev);
318         struct acpi_driver *acpi_drv = acpi_dev->driver;
319
320         if (acpi_drv && acpi_drv->ops.suspend)
321                 return acpi_drv->ops.suspend(acpi_dev, state);
322         return 0;
323 }
324
325 static int acpi_device_resume(struct device *dev)
326 {
327         struct acpi_device *acpi_dev = to_acpi_device(dev);
328         struct acpi_driver *acpi_drv = acpi_dev->driver;
329
330         if (acpi_drv && acpi_drv->ops.resume)
331                 return acpi_drv->ops.resume(acpi_dev);
332         return 0;
333 }
334
335 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
336 {
337         struct acpi_device *acpi_dev = to_acpi_device(dev);
338         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
339
340         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
341 }
342
343 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
344 {
345         struct acpi_device *acpi_dev = to_acpi_device(dev);
346         int len;
347
348         if (add_uevent_var(env, "MODALIAS="))
349                 return -ENOMEM;
350         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
351                               sizeof(env->buf) - env->buflen);
352         if (len >= (sizeof(env->buf) - env->buflen))
353                 return -ENOMEM;
354         env->buflen += len;
355         return 0;
356 }
357
358 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
359 {
360         struct acpi_device *device = data;
361
362         device->driver->ops.notify(device, event);
363 }
364
365 static acpi_status acpi_device_notify_fixed(void *data)
366 {
367         struct acpi_device *device = data;
368
369         acpi_device_notify(device->handle, ACPI_FIXED_HARDWARE_EVENT, device);
370         return AE_OK;
371 }
372
373 static int acpi_device_install_notify_handler(struct acpi_device *device)
374 {
375         acpi_status status;
376         char *hid;
377
378         hid = acpi_device_hid(device);
379         if (!strcmp(hid, ACPI_BUTTON_HID_POWERF))
380                 status =
381                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
382                                                      acpi_device_notify_fixed,
383                                                      device);
384         else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEPF))
385                 status =
386                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
387                                                      acpi_device_notify_fixed,
388                                                      device);
389         else
390                 status = acpi_install_notify_handler(device->handle,
391                                                      ACPI_DEVICE_NOTIFY,
392                                                      acpi_device_notify,
393                                                      device);
394
395         if (ACPI_FAILURE(status))
396                 return -EINVAL;
397         return 0;
398 }
399
400 static void acpi_device_remove_notify_handler(struct acpi_device *device)
401 {
402         if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_POWERF))
403                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
404                                                 acpi_device_notify_fixed);
405         else if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_SLEEPF))
406                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
407                                                 acpi_device_notify_fixed);
408         else
409                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
410                                            acpi_device_notify);
411 }
412
413 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
414 static int acpi_start_single_object(struct acpi_device *);
415 static int acpi_device_probe(struct device * dev)
416 {
417         struct acpi_device *acpi_dev = to_acpi_device(dev);
418         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
419         int ret;
420
421         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
422         if (!ret) {
423                 if (acpi_dev->bus_ops.acpi_op_start)
424                         acpi_start_single_object(acpi_dev);
425
426                 if (acpi_drv->ops.notify) {
427                         ret = acpi_device_install_notify_handler(acpi_dev);
428                         if (ret) {
429                                 if (acpi_drv->ops.stop)
430                                         acpi_drv->ops.stop(acpi_dev,
431                                                    acpi_dev->removal_type);
432                                 if (acpi_drv->ops.remove)
433                                         acpi_drv->ops.remove(acpi_dev,
434                                                      acpi_dev->removal_type);
435                                 return ret;
436                         }
437                 }
438
439                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
440                         "Found driver [%s] for device [%s]\n",
441                         acpi_drv->name, acpi_dev->pnp.bus_id));
442                 get_device(dev);
443         }
444         return ret;
445 }
446
447 static int acpi_device_remove(struct device * dev)
448 {
449         struct acpi_device *acpi_dev = to_acpi_device(dev);
450         struct acpi_driver *acpi_drv = acpi_dev->driver;
451
452         if (acpi_drv) {
453                 if (acpi_drv->ops.notify)
454                         acpi_device_remove_notify_handler(acpi_dev);
455                 if (acpi_drv->ops.stop)
456                         acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
457                 if (acpi_drv->ops.remove)
458                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
459         }
460         acpi_dev->driver = NULL;
461         acpi_dev->driver_data = NULL;
462
463         put_device(dev);
464         return 0;
465 }
466
467 struct bus_type acpi_bus_type = {
468         .name           = "acpi",
469         .suspend        = acpi_device_suspend,
470         .resume         = acpi_device_resume,
471         .match          = acpi_bus_match,
472         .probe          = acpi_device_probe,
473         .remove         = acpi_device_remove,
474         .uevent         = acpi_device_uevent,
475 };
476
477 static int acpi_device_register(struct acpi_device *device,
478                                  struct acpi_device *parent)
479 {
480         int result;
481         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
482         int found = 0;
483         /*
484          * Linkage
485          * -------
486          * Link this device to its parent and siblings.
487          */
488         INIT_LIST_HEAD(&device->children);
489         INIT_LIST_HEAD(&device->node);
490         INIT_LIST_HEAD(&device->wakeup_list);
491
492         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
493         if (!new_bus_id) {
494                 printk(KERN_ERR PREFIX "Memory allocation error\n");
495                 return -ENOMEM;
496         }
497
498         mutex_lock(&acpi_device_lock);
499         /*
500          * Find suitable bus_id and instance number in acpi_bus_id_list
501          * If failed, create one and link it into acpi_bus_id_list
502          */
503         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
504                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
505                         acpi_device_bus_id->instance_no ++;
506                         found = 1;
507                         kfree(new_bus_id);
508                         break;
509                 }
510         }
511         if (!found) {
512                 acpi_device_bus_id = new_bus_id;
513                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
514                 acpi_device_bus_id->instance_no = 0;
515                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
516         }
517         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
518
519         if (device->parent)
520                 list_add_tail(&device->node, &device->parent->children);
521
522         if (device->wakeup.flags.valid)
523                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
524         mutex_unlock(&acpi_device_lock);
525
526         if (device->parent)
527                 device->dev.parent = &parent->dev;
528         device->dev.bus = &acpi_bus_type;
529         device->dev.release = &acpi_device_release;
530         result = device_register(&device->dev);
531         if (result) {
532                 dev_err(&device->dev, "Error registering device\n");
533                 goto end;
534         }
535
536         result = acpi_device_setup_files(device);
537         if (result)
538                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
539                        dev_name(&device->dev));
540
541         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
542         return 0;
543 end:
544         mutex_lock(&acpi_device_lock);
545         if (device->parent)
546                 list_del(&device->node);
547         list_del(&device->wakeup_list);
548         mutex_unlock(&acpi_device_lock);
549         return result;
550 }
551
552 static void acpi_device_unregister(struct acpi_device *device, int type)
553 {
554         mutex_lock(&acpi_device_lock);
555         if (device->parent)
556                 list_del(&device->node);
557
558         list_del(&device->wakeup_list);
559         mutex_unlock(&acpi_device_lock);
560
561         acpi_detach_data(device->handle, acpi_bus_data_handler);
562
563         acpi_device_remove_files(device);
564         device_unregister(&device->dev);
565 }
566
567 /* --------------------------------------------------------------------------
568                                  Driver Management
569    -------------------------------------------------------------------------- */
570 /**
571  * acpi_bus_driver_init - add a device to a driver
572  * @device: the device to add and initialize
573  * @driver: driver for the device
574  *
575  * Used to initialize a device via its device driver.  Called whenever a
576  * driver is bound to a device.  Invokes the driver's add() ops.
577  */
578 static int
579 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
580 {
581         int result = 0;
582
583         if (!device || !driver)
584                 return -EINVAL;
585
586         if (!driver->ops.add)
587                 return -ENOSYS;
588
589         result = driver->ops.add(device);
590         if (result) {
591                 device->driver = NULL;
592                 device->driver_data = NULL;
593                 return result;
594         }
595
596         device->driver = driver;
597
598         /*
599          * TBD - Configuration Management: Assign resources to device based
600          * upon possible configuration and currently allocated resources.
601          */
602
603         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
604                           "Driver successfully bound to device\n"));
605         return 0;
606 }
607
608 static int acpi_start_single_object(struct acpi_device *device)
609 {
610         int result = 0;
611         struct acpi_driver *driver;
612
613
614         if (!(driver = device->driver))
615                 return 0;
616
617         if (driver->ops.start) {
618                 result = driver->ops.start(device);
619                 if (result && driver->ops.remove)
620                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
621         }
622
623         return result;
624 }
625
626 /**
627  * acpi_bus_register_driver - register a driver with the ACPI bus
628  * @driver: driver being registered
629  *
630  * Registers a driver with the ACPI bus.  Searches the namespace for all
631  * devices that match the driver's criteria and binds.  Returns zero for
632  * success or a negative error status for failure.
633  */
634 int acpi_bus_register_driver(struct acpi_driver *driver)
635 {
636         int ret;
637
638         if (acpi_disabled)
639                 return -ENODEV;
640         driver->drv.name = driver->name;
641         driver->drv.bus = &acpi_bus_type;
642         driver->drv.owner = driver->owner;
643
644         ret = driver_register(&driver->drv);
645         return ret;
646 }
647
648 EXPORT_SYMBOL(acpi_bus_register_driver);
649
650 /**
651  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
652  * @driver: driver to unregister
653  *
654  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
655  * devices that match the driver's criteria and unbinds.
656  */
657 void acpi_bus_unregister_driver(struct acpi_driver *driver)
658 {
659         driver_unregister(&driver->drv);
660 }
661
662 EXPORT_SYMBOL(acpi_bus_unregister_driver);
663
664 /* --------------------------------------------------------------------------
665                                  Device Enumeration
666    -------------------------------------------------------------------------- */
667 acpi_status
668 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
669 {
670         acpi_status status;
671         acpi_handle tmp;
672         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
673         union acpi_object *obj;
674
675         status = acpi_get_handle(handle, "_EJD", &tmp);
676         if (ACPI_FAILURE(status))
677                 return status;
678
679         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
680         if (ACPI_SUCCESS(status)) {
681                 obj = buffer.pointer;
682                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
683                                          ejd);
684                 kfree(buffer.pointer);
685         }
686         return status;
687 }
688 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
689
690 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
691 {
692
693         /* TBD */
694
695         return;
696 }
697
698 static int acpi_bus_get_perf_flags(struct acpi_device *device)
699 {
700         device->performance.state = ACPI_STATE_UNKNOWN;
701         return 0;
702 }
703
704 static acpi_status
705 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
706                                              union acpi_object *package)
707 {
708         int i = 0;
709         union acpi_object *element = NULL;
710
711         if (!device || !package || (package->package.count < 2))
712                 return AE_BAD_PARAMETER;
713
714         element = &(package->package.elements[0]);
715         if (!element)
716                 return AE_BAD_PARAMETER;
717         if (element->type == ACPI_TYPE_PACKAGE) {
718                 if ((element->package.count < 2) ||
719                     (element->package.elements[0].type !=
720                      ACPI_TYPE_LOCAL_REFERENCE)
721                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
722                         return AE_BAD_DATA;
723                 device->wakeup.gpe_device =
724                     element->package.elements[0].reference.handle;
725                 device->wakeup.gpe_number =
726                     (u32) element->package.elements[1].integer.value;
727         } else if (element->type == ACPI_TYPE_INTEGER) {
728                 device->wakeup.gpe_number = element->integer.value;
729         } else
730                 return AE_BAD_DATA;
731
732         element = &(package->package.elements[1]);
733         if (element->type != ACPI_TYPE_INTEGER) {
734                 return AE_BAD_DATA;
735         }
736         device->wakeup.sleep_state = element->integer.value;
737
738         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
739                 return AE_NO_MEMORY;
740         }
741         device->wakeup.resources.count = package->package.count - 2;
742         for (i = 0; i < device->wakeup.resources.count; i++) {
743                 element = &(package->package.elements[i + 2]);
744                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
745                         return AE_BAD_DATA;
746
747                 device->wakeup.resources.handles[i] = element->reference.handle;
748         }
749
750         return AE_OK;
751 }
752
753 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
754 {
755         acpi_status status = 0;
756         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
757         union acpi_object *package = NULL;
758         int psw_error;
759
760         struct acpi_device_id button_device_ids[] = {
761                 {"PNP0C0D", 0},
762                 {"PNP0C0C", 0},
763                 {"PNP0C0E", 0},
764                 {"", 0},
765         };
766
767         /* _PRW */
768         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
769         if (ACPI_FAILURE(status)) {
770                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
771                 goto end;
772         }
773
774         package = (union acpi_object *)buffer.pointer;
775         status = acpi_bus_extract_wakeup_device_power_package(device, package);
776         if (ACPI_FAILURE(status)) {
777                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
778                 goto end;
779         }
780
781         kfree(buffer.pointer);
782
783         device->wakeup.flags.valid = 1;
784         device->wakeup.prepare_count = 0;
785         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
786          * system for the ACPI device with the _PRW object.
787          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
788          * So it is necessary to call _DSW object first. Only when it is not
789          * present will the _PSW object used.
790          */
791         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
792         if (psw_error)
793                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
794                                 "error in _DSW or _PSW evaluation\n"));
795
796         /* Power button, Lid switch always enable wakeup */
797         if (!acpi_match_device_ids(device, button_device_ids))
798                 device->wakeup.flags.run_wake = 1;
799
800 end:
801         if (ACPI_FAILURE(status))
802                 device->flags.wake_capable = 0;
803         return 0;
804 }
805
806 static int acpi_bus_get_power_flags(struct acpi_device *device)
807 {
808         acpi_status status = 0;
809         acpi_handle handle = NULL;
810         u32 i = 0;
811
812
813         /*
814          * Power Management Flags
815          */
816         status = acpi_get_handle(device->handle, "_PSC", &handle);
817         if (ACPI_SUCCESS(status))
818                 device->power.flags.explicit_get = 1;
819         status = acpi_get_handle(device->handle, "_IRC", &handle);
820         if (ACPI_SUCCESS(status))
821                 device->power.flags.inrush_current = 1;
822
823         /*
824          * Enumerate supported power management states
825          */
826         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
827                 struct acpi_device_power_state *ps = &device->power.states[i];
828                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
829
830                 /* Evaluate "_PRx" to se if power resources are referenced */
831                 acpi_evaluate_reference(device->handle, object_name, NULL,
832                                         &ps->resources);
833                 if (ps->resources.count) {
834                         device->power.flags.power_resources = 1;
835                         ps->flags.valid = 1;
836                 }
837
838                 /* Evaluate "_PSx" to see if we can do explicit sets */
839                 object_name[2] = 'S';
840                 status = acpi_get_handle(device->handle, object_name, &handle);
841                 if (ACPI_SUCCESS(status)) {
842                         ps->flags.explicit_set = 1;
843                         ps->flags.valid = 1;
844                 }
845
846                 /* State is valid if we have some power control */
847                 if (ps->resources.count || ps->flags.explicit_set)
848                         ps->flags.valid = 1;
849
850                 ps->power = -1; /* Unknown - driver assigned */
851                 ps->latency = -1;       /* Unknown - driver assigned */
852         }
853
854         /* Set defaults for D0 and D3 states (always valid) */
855         device->power.states[ACPI_STATE_D0].flags.valid = 1;
856         device->power.states[ACPI_STATE_D0].power = 100;
857         device->power.states[ACPI_STATE_D3].flags.valid = 1;
858         device->power.states[ACPI_STATE_D3].power = 0;
859
860         /* TBD: System wake support and resource requirements. */
861
862         device->power.state = ACPI_STATE_UNKNOWN;
863         acpi_bus_get_power(device->handle, &(device->power.state));
864
865         return 0;
866 }
867
868 static int acpi_bus_get_flags(struct acpi_device *device)
869 {
870         acpi_status status = AE_OK;
871         acpi_handle temp = NULL;
872
873
874         /* Presence of _STA indicates 'dynamic_status' */
875         status = acpi_get_handle(device->handle, "_STA", &temp);
876         if (ACPI_SUCCESS(status))
877                 device->flags.dynamic_status = 1;
878
879         /* Presence of _CID indicates 'compatible_ids' */
880         status = acpi_get_handle(device->handle, "_CID", &temp);
881         if (ACPI_SUCCESS(status))
882                 device->flags.compatible_ids = 1;
883
884         /* Presence of _RMV indicates 'removable' */
885         status = acpi_get_handle(device->handle, "_RMV", &temp);
886         if (ACPI_SUCCESS(status))
887                 device->flags.removable = 1;
888
889         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
890         status = acpi_get_handle(device->handle, "_EJD", &temp);
891         if (ACPI_SUCCESS(status))
892                 device->flags.ejectable = 1;
893         else {
894                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
895                 if (ACPI_SUCCESS(status))
896                         device->flags.ejectable = 1;
897         }
898
899         /* Presence of _LCK indicates 'lockable' */
900         status = acpi_get_handle(device->handle, "_LCK", &temp);
901         if (ACPI_SUCCESS(status))
902                 device->flags.lockable = 1;
903
904         /* Presence of _PS0|_PR0 indicates 'power manageable' */
905         status = acpi_get_handle(device->handle, "_PS0", &temp);
906         if (ACPI_FAILURE(status))
907                 status = acpi_get_handle(device->handle, "_PR0", &temp);
908         if (ACPI_SUCCESS(status))
909                 device->flags.power_manageable = 1;
910
911         /* Presence of _PRW indicates wake capable */
912         status = acpi_get_handle(device->handle, "_PRW", &temp);
913         if (ACPI_SUCCESS(status))
914                 device->flags.wake_capable = 1;
915
916         /* TBD: Performance management */
917
918         return 0;
919 }
920
921 static void acpi_device_get_busid(struct acpi_device *device,
922                                   acpi_handle handle, int type)
923 {
924         char bus_id[5] = { '?', 0 };
925         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
926         int i = 0;
927
928         /*
929          * Bus ID
930          * ------
931          * The device's Bus ID is simply the object name.
932          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
933          */
934         switch (type) {
935         case ACPI_BUS_TYPE_SYSTEM:
936                 strcpy(device->pnp.bus_id, "ACPI");
937                 break;
938         case ACPI_BUS_TYPE_POWER_BUTTON:
939                 strcpy(device->pnp.bus_id, "PWRF");
940                 break;
941         case ACPI_BUS_TYPE_SLEEP_BUTTON:
942                 strcpy(device->pnp.bus_id, "SLPF");
943                 break;
944         default:
945                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
946                 /* Clean up trailing underscores (if any) */
947                 for (i = 3; i > 1; i--) {
948                         if (bus_id[i] == '_')
949                                 bus_id[i] = '\0';
950                         else
951                                 break;
952                 }
953                 strcpy(device->pnp.bus_id, bus_id);
954                 break;
955         }
956 }
957
958 /*
959  * acpi_bay_match - see if a device is an ejectable driver bay
960  *
961  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
962  * then we can safely call it an ejectable drive bay
963  */
964 static int acpi_bay_match(struct acpi_device *device){
965         acpi_status status;
966         acpi_handle handle;
967         acpi_handle tmp;
968         acpi_handle phandle;
969
970         handle = device->handle;
971
972         status = acpi_get_handle(handle, "_EJ0", &tmp);
973         if (ACPI_FAILURE(status))
974                 return -ENODEV;
975
976         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
977                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
978                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
979                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
980                 return 0;
981
982         if (acpi_get_parent(handle, &phandle))
983                 return -ENODEV;
984
985         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
986                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
987                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
988                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
989                 return 0;
990
991         return -ENODEV;
992 }
993
994 /*
995  * acpi_dock_match - see if a device has a _DCK method
996  */
997 static int acpi_dock_match(struct acpi_device *device)
998 {
999         acpi_handle tmp;
1000         return acpi_get_handle(device->handle, "_DCK", &tmp);
1001 }
1002
1003 static void acpi_device_set_id(struct acpi_device *device,
1004                                struct acpi_device *parent, acpi_handle handle,
1005                                int type)
1006 {
1007         struct acpi_device_info *info;
1008         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1009         char *hid = NULL;
1010         char *uid = NULL;
1011         struct acpi_compatible_id_list *cid_list = NULL;
1012         const char *cid_add = NULL;
1013         acpi_status status;
1014
1015         switch (type) {
1016         case ACPI_BUS_TYPE_DEVICE:
1017                 status = acpi_get_object_info(handle, &buffer);
1018                 if (ACPI_FAILURE(status)) {
1019                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1020                         return;
1021                 }
1022
1023                 info = buffer.pointer;
1024                 if (info->valid & ACPI_VALID_HID)
1025                         hid = info->hardware_id.value;
1026                 if (info->valid & ACPI_VALID_UID)
1027                         uid = info->unique_id.value;
1028                 if (info->valid & ACPI_VALID_CID)
1029                         cid_list = &info->compatibility_id;
1030                 if (info->valid & ACPI_VALID_ADR) {
1031                         device->pnp.bus_address = info->address;
1032                         device->flags.bus_address = 1;
1033                 }
1034
1035                 /* If we have a video/bay/dock device, add our selfdefined
1036                    HID to the CID list. Like that the video/bay/dock drivers
1037                    will get autoloaded and the device might still match
1038                    against another driver.
1039                 */
1040                 if (acpi_is_video_device(device))
1041                         cid_add = ACPI_VIDEO_HID;
1042                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1043                         cid_add = ACPI_BAY_HID;
1044                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1045                         cid_add = ACPI_DOCK_HID;
1046
1047                 break;
1048         case ACPI_BUS_TYPE_POWER:
1049                 hid = ACPI_POWER_HID;
1050                 break;
1051         case ACPI_BUS_TYPE_PROCESSOR:
1052                 hid = ACPI_PROCESSOR_OBJECT_HID;
1053                 break;
1054         case ACPI_BUS_TYPE_SYSTEM:
1055                 hid = ACPI_SYSTEM_HID;
1056                 break;
1057         case ACPI_BUS_TYPE_THERMAL:
1058                 hid = ACPI_THERMAL_HID;
1059                 break;
1060         case ACPI_BUS_TYPE_POWER_BUTTON:
1061                 hid = ACPI_BUTTON_HID_POWERF;
1062                 break;
1063         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1064                 hid = ACPI_BUTTON_HID_SLEEPF;
1065                 break;
1066         }
1067
1068         /*
1069          * \_SB
1070          * ----
1071          * Fix for the system root bus device -- the only root-level device.
1072          */
1073         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1074                 hid = ACPI_BUS_HID;
1075                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1076                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1077         }
1078
1079         if (hid) {
1080                 strcpy(device->pnp.hardware_id, hid);
1081                 device->flags.hardware_id = 1;
1082         }
1083         if (uid) {
1084                 strcpy(device->pnp.unique_id, uid);
1085                 device->flags.unique_id = 1;
1086         }
1087         if (cid_list || cid_add) {
1088                 struct  acpi_compatible_id_list *list;
1089                 int size = 0;
1090                 int count = 0;
1091
1092                 if (cid_list) {
1093                         size = cid_list->size;
1094                 } else if (cid_add) {
1095                         size = sizeof(struct acpi_compatible_id_list);
1096                         cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1097                         if (!cid_list) {
1098                                 printk(KERN_ERR "Memory allocation error\n");
1099                                 kfree(buffer.pointer);
1100                                 return;
1101                         } else {
1102                                 cid_list->count = 0;
1103                                 cid_list->size = size;
1104                         }
1105                 }
1106                 if (cid_add)
1107                         size += sizeof(struct acpi_compatible_id);
1108                 list = kmalloc(size, GFP_KERNEL);
1109
1110                 if (list) {
1111                         if (cid_list) {
1112                                 memcpy(list, cid_list, cid_list->size);
1113                                 count = cid_list->count;
1114                         }
1115                         if (cid_add) {
1116                                 strncpy(list->id[count].value, cid_add,
1117                                         ACPI_MAX_CID_LENGTH);
1118                                 count++;
1119                                 device->flags.compatible_ids = 1;
1120                         }
1121                         list->size = size;
1122                         list->count = count;
1123                         device->pnp.cid_list = list;
1124                 } else
1125                         printk(KERN_ERR PREFIX "Memory allocation error\n");
1126         }
1127
1128         kfree(buffer.pointer);
1129 }
1130
1131 static int acpi_device_set_context(struct acpi_device *device, int type)
1132 {
1133         acpi_status status = AE_OK;
1134         int result = 0;
1135         /*
1136          * Context
1137          * -------
1138          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1139          * resolutions from handle->device very efficient.  Note that we need
1140          * to be careful with fixed-feature devices as they all attach to the
1141          * root object.
1142          */
1143         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1144             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1145                 status = acpi_attach_data(device->handle,
1146                                           acpi_bus_data_handler, device);
1147
1148                 if (ACPI_FAILURE(status)) {
1149                         printk(KERN_ERR PREFIX "Error attaching device data\n");
1150                         result = -ENODEV;
1151                 }
1152         }
1153         return result;
1154 }
1155
1156 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1157 {
1158         if (!dev)
1159                 return -EINVAL;
1160
1161         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1162         device_release_driver(&dev->dev);
1163
1164         if (!rmdevice)
1165                 return 0;
1166
1167         /*
1168          * unbind _ADR-Based Devices when hot removal
1169          */
1170         if (dev->flags.bus_address) {
1171                 if ((dev->parent) && (dev->parent->ops.unbind))
1172                         dev->parent->ops.unbind(dev);
1173         }
1174         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1175
1176         return 0;
1177 }
1178
1179 static int
1180 acpi_add_single_object(struct acpi_device **child,
1181                        struct acpi_device *parent, acpi_handle handle, int type,
1182                         struct acpi_bus_ops *ops)
1183 {
1184         int result = 0;
1185         struct acpi_device *device = NULL;
1186
1187
1188         if (!child)
1189                 return -EINVAL;
1190
1191         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1192         if (!device) {
1193                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1194                 return -ENOMEM;
1195         }
1196
1197         device->handle = handle;
1198         device->parent = parent;
1199         device->bus_ops = *ops; /* workround for not call .start */
1200
1201
1202         acpi_device_get_busid(device, handle, type);
1203
1204         /*
1205          * Flags
1206          * -----
1207          * Get prior to calling acpi_bus_get_status() so we know whether
1208          * or not _STA is present.  Note that we only look for object
1209          * handles -- cannot evaluate objects until we know the device is
1210          * present and properly initialized.
1211          */
1212         result = acpi_bus_get_flags(device);
1213         if (result)
1214                 goto end;
1215
1216         /*
1217          * Status
1218          * ------
1219          * See if the device is present.  We always assume that non-Device
1220          * and non-Processor objects (e.g. thermal zones, power resources,
1221          * etc.) are present, functioning, etc. (at least when parent object
1222          * is present).  Note that _STA has a different meaning for some
1223          * objects (e.g. power resources) so we need to be careful how we use
1224          * it.
1225          */
1226         switch (type) {
1227         case ACPI_BUS_TYPE_PROCESSOR:
1228         case ACPI_BUS_TYPE_DEVICE:
1229                 result = acpi_bus_get_status(device);
1230                 if (ACPI_FAILURE(result)) {
1231                         result = -ENODEV;
1232                         goto end;
1233                 }
1234                 /*
1235                  * When the device is neither present nor functional, the
1236                  * device should not be added to Linux ACPI device tree.
1237                  * When the status of the device is not present but functinal,
1238                  * it should be added to Linux ACPI tree. For example : bay
1239                  * device , dock device.
1240                  * In such conditions it is unncessary to check whether it is
1241                  * bay device or dock device.
1242                  */
1243                 if (!device->status.present && !device->status.functional) {
1244                         result = -ENODEV;
1245                         goto end;
1246                 }
1247                 break;
1248         default:
1249                 STRUCT_TO_INT(device->status) =
1250                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1251                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1252                 break;
1253         }
1254
1255         /*
1256          * Initialize Device
1257          * -----------------
1258          * TBD: Synch with Core's enumeration/initialization process.
1259          */
1260
1261         /*
1262          * Hardware ID, Unique ID, & Bus Address
1263          * -------------------------------------
1264          */
1265         acpi_device_set_id(device, parent, handle, type);
1266
1267         /*
1268          * Power Management
1269          * ----------------
1270          */
1271         if (device->flags.power_manageable) {
1272                 result = acpi_bus_get_power_flags(device);
1273                 if (result)
1274                         goto end;
1275         }
1276
1277         /*
1278          * Wakeup device management
1279          *-----------------------
1280          */
1281         if (device->flags.wake_capable) {
1282                 result = acpi_bus_get_wakeup_device_flags(device);
1283                 if (result)
1284                         goto end;
1285         }
1286
1287         /*
1288          * Performance Management
1289          * ----------------------
1290          */
1291         if (device->flags.performance_manageable) {
1292                 result = acpi_bus_get_perf_flags(device);
1293                 if (result)
1294                         goto end;
1295         }
1296
1297         if ((result = acpi_device_set_context(device, type)))
1298                 goto end;
1299
1300         result = acpi_device_register(device, parent);
1301
1302         /*
1303          * Bind _ADR-Based Devices when hot add
1304          */
1305         if (device->flags.bus_address) {
1306                 if (device->parent && device->parent->ops.bind)
1307                         device->parent->ops.bind(device);
1308         }
1309
1310 end:
1311         if (!result)
1312                 *child = device;
1313         else {
1314                 kfree(device->pnp.cid_list);
1315                 kfree(device);
1316         }
1317
1318         return result;
1319 }
1320
1321 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1322 {
1323         acpi_status status = AE_OK;
1324         struct acpi_device *parent = NULL;
1325         struct acpi_device *child = NULL;
1326         acpi_handle phandle = NULL;
1327         acpi_handle chandle = NULL;
1328         acpi_object_type type = 0;
1329         u32 level = 1;
1330
1331
1332         if (!start)
1333                 return -EINVAL;
1334
1335         parent = start;
1336         phandle = start->handle;
1337
1338         /*
1339          * Parse through the ACPI namespace, identify all 'devices', and
1340          * create a new 'struct acpi_device' for each.
1341          */
1342         while ((level > 0) && parent) {
1343
1344                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1345                                               chandle, &chandle);
1346
1347                 /*
1348                  * If this scope is exhausted then move our way back up.
1349                  */
1350                 if (ACPI_FAILURE(status)) {
1351                         level--;
1352                         chandle = phandle;
1353                         acpi_get_parent(phandle, &phandle);
1354                         if (parent->parent)
1355                                 parent = parent->parent;
1356                         continue;
1357                 }
1358
1359                 status = acpi_get_type(chandle, &type);
1360                 if (ACPI_FAILURE(status))
1361                         continue;
1362
1363                 /*
1364                  * If this is a scope object then parse it (depth-first).
1365                  */
1366                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1367                         level++;
1368                         phandle = chandle;
1369                         chandle = NULL;
1370                         continue;
1371                 }
1372
1373                 /*
1374                  * We're only interested in objects that we consider 'devices'.
1375                  */
1376                 switch (type) {
1377                 case ACPI_TYPE_DEVICE:
1378                         type = ACPI_BUS_TYPE_DEVICE;
1379                         break;
1380                 case ACPI_TYPE_PROCESSOR:
1381                         type = ACPI_BUS_TYPE_PROCESSOR;
1382                         break;
1383                 case ACPI_TYPE_THERMAL:
1384                         type = ACPI_BUS_TYPE_THERMAL;
1385                         break;
1386                 case ACPI_TYPE_POWER:
1387                         type = ACPI_BUS_TYPE_POWER;
1388                         break;
1389                 default:
1390                         continue;
1391                 }
1392
1393                 if (ops->acpi_op_add)
1394                         status = acpi_add_single_object(&child, parent,
1395                                 chandle, type, ops);
1396                 else
1397                         status = acpi_bus_get_device(chandle, &child);
1398
1399                 if (ACPI_FAILURE(status))
1400                         continue;
1401
1402                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1403                         status = acpi_start_single_object(child);
1404                         if (ACPI_FAILURE(status))
1405                                 continue;
1406                 }
1407
1408                 /*
1409                  * If the device is present, enabled, and functioning then
1410                  * parse its scope (depth-first).  Note that we need to
1411                  * represent absent devices to facilitate PnP notifications
1412                  * -- but only the subtree head (not all of its children,
1413                  * which will be enumerated when the parent is inserted).
1414                  *
1415                  * TBD: Need notifications and other detection mechanisms
1416                  *      in place before we can fully implement this.
1417                  */
1418                  /*
1419                  * When the device is not present but functional, it is also
1420                  * necessary to scan the children of this device.
1421                  */
1422                 if (child->status.present || (!child->status.present &&
1423                                         child->status.functional)) {
1424                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1425                                                       NULL, NULL);
1426                         if (ACPI_SUCCESS(status)) {
1427                                 level++;
1428                                 phandle = chandle;
1429                                 chandle = NULL;
1430                                 parent = child;
1431                         }
1432                 }
1433         }
1434
1435         return 0;
1436 }
1437
1438 int
1439 acpi_bus_add(struct acpi_device **child,
1440              struct acpi_device *parent, acpi_handle handle, int type)
1441 {
1442         int result;
1443         struct acpi_bus_ops ops;
1444
1445         memset(&ops, 0, sizeof(ops));
1446         ops.acpi_op_add = 1;
1447
1448         result = acpi_add_single_object(child, parent, handle, type, &ops);
1449         if (!result)
1450                 result = acpi_bus_scan(*child, &ops);
1451
1452         return result;
1453 }
1454 EXPORT_SYMBOL(acpi_bus_add);
1455
1456 int acpi_bus_start(struct acpi_device *device)
1457 {
1458         int result;
1459         struct acpi_bus_ops ops;
1460
1461
1462         if (!device)
1463                 return -EINVAL;
1464
1465         result = acpi_start_single_object(device);
1466         if (!result) {
1467                 memset(&ops, 0, sizeof(ops));
1468                 ops.acpi_op_start = 1;
1469                 result = acpi_bus_scan(device, &ops);
1470         }
1471         return result;
1472 }
1473 EXPORT_SYMBOL(acpi_bus_start);
1474
1475 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1476 {
1477         acpi_status status;
1478         struct acpi_device *parent, *child;
1479         acpi_handle phandle, chandle;
1480         acpi_object_type type;
1481         u32 level = 1;
1482         int err = 0;
1483
1484         parent = start;
1485         phandle = start->handle;
1486         child = chandle = NULL;
1487
1488         while ((level > 0) && parent && (!err)) {
1489                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1490                                               chandle, &chandle);
1491
1492                 /*
1493                  * If this scope is exhausted then move our way back up.
1494                  */
1495                 if (ACPI_FAILURE(status)) {
1496                         level--;
1497                         chandle = phandle;
1498                         acpi_get_parent(phandle, &phandle);
1499                         child = parent;
1500                         parent = parent->parent;
1501
1502                         if (level == 0)
1503                                 err = acpi_bus_remove(child, rmdevice);
1504                         else
1505                                 err = acpi_bus_remove(child, 1);
1506
1507                         continue;
1508                 }
1509
1510                 status = acpi_get_type(chandle, &type);
1511                 if (ACPI_FAILURE(status)) {
1512                         continue;
1513                 }
1514                 /*
1515                  * If there is a device corresponding to chandle then
1516                  * parse it (depth-first).
1517                  */
1518                 if (acpi_bus_get_device(chandle, &child) == 0) {
1519                         level++;
1520                         phandle = chandle;
1521                         chandle = NULL;
1522                         parent = child;
1523                 }
1524                 continue;
1525         }
1526         return err;
1527 }
1528 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1529
1530 static int acpi_bus_scan_fixed(struct acpi_device *root)
1531 {
1532         int result = 0;
1533         struct acpi_device *device = NULL;
1534         struct acpi_bus_ops ops;
1535
1536         if (!root)
1537                 return -ENODEV;
1538
1539         memset(&ops, 0, sizeof(ops));
1540         ops.acpi_op_add = 1;
1541         ops.acpi_op_start = 1;
1542
1543         /*
1544          * Enumerate all fixed-feature devices.
1545          */
1546         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1547                 result = acpi_add_single_object(&device, acpi_root,
1548                                                 NULL,
1549                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1550                                                 &ops);
1551         }
1552
1553         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1554                 result = acpi_add_single_object(&device, acpi_root,
1555                                                 NULL,
1556                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1557                                                 &ops);
1558         }
1559
1560         return result;
1561 }
1562
1563 int __init acpi_scan_init(void)
1564 {
1565         int result;
1566         struct acpi_bus_ops ops;
1567
1568         memset(&ops, 0, sizeof(ops));
1569         ops.acpi_op_add = 1;
1570         ops.acpi_op_start = 1;
1571
1572         result = bus_register(&acpi_bus_type);
1573         if (result) {
1574                 /* We don't want to quit even if we failed to add suspend/resume */
1575                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1576         }
1577
1578         /*
1579          * Create the root device in the bus's device tree
1580          */
1581         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1582                                         ACPI_BUS_TYPE_SYSTEM, &ops);
1583         if (result)
1584                 goto Done;
1585
1586         /*
1587          * Enumerate devices in the ACPI namespace.
1588          */
1589         result = acpi_bus_scan_fixed(acpi_root);
1590
1591         if (!result)
1592                 result = acpi_bus_scan(acpi_root, &ops);
1593
1594         if (result)
1595                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1596
1597 Done:
1598         return result;
1599 }