Merge branch 'trivial' of git://git.kernel.dk/data/git/linux-2.6-block
[linux-2.6] / drivers / acpi / bus.c
1 /*
2  *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
3  *
4  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or (at
11  *  your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful, but
14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *  General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License along
19  *  with this program; if not, write to the Free Software Foundation, Inc.,
20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  */
24
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/ioport.h>
28 #include <linux/kernel.h>
29 #include <linux/list.h>
30 #include <linux/sched.h>
31 #include <linux/pm.h>
32 #include <linux/pm_legacy.h>
33 #include <linux/device.h>
34 #include <linux/proc_fs.h>
35 #ifdef CONFIG_X86
36 #include <asm/mpspec.h>
37 #endif
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
40
41 #define _COMPONENT              ACPI_BUS_COMPONENT
42 ACPI_MODULE_NAME("bus");
43 #ifdef  CONFIG_X86
44 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
45 #endif
46
47 struct acpi_device *acpi_root;
48 struct proc_dir_entry *acpi_root_dir;
49 EXPORT_SYMBOL(acpi_root_dir);
50
51 #define STRUCT_TO_INT(s)        (*((int*)&s))
52
53 /* --------------------------------------------------------------------------
54                                 Device Management
55    -------------------------------------------------------------------------- */
56
57 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
58 {
59         acpi_status status = AE_OK;
60
61
62         if (!device)
63                 return -EINVAL;
64
65         /* TBD: Support fixed-feature devices */
66
67         status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
68         if (ACPI_FAILURE(status) || !*device) {
69                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
70                                   handle));
71                 return -ENODEV;
72         }
73
74         return 0;
75 }
76
77 EXPORT_SYMBOL(acpi_bus_get_device);
78
79 int acpi_bus_get_status(struct acpi_device *device)
80 {
81         acpi_status status = AE_OK;
82         unsigned long sta = 0;
83
84
85         if (!device)
86                 return -EINVAL;
87
88         /*
89          * Evaluate _STA if present.
90          */
91         if (device->flags.dynamic_status) {
92                 status =
93                     acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
94                 if (ACPI_FAILURE(status))
95                         return -ENODEV;
96                 STRUCT_TO_INT(device->status) = (int)sta;
97         }
98
99         /*
100          * Otherwise we assume the status of our parent (unless we don't
101          * have one, in which case status is implied).
102          */
103         else if (device->parent)
104                 device->status = device->parent->status;
105         else
106                 STRUCT_TO_INT(device->status) =
107                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
108                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
109
110         if (device->status.functional && !device->status.present) {
111                 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
112                        "functional but not present; setting present\n",
113                        device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
114                 device->status.present = 1;
115         }
116
117         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
118                           device->pnp.bus_id,
119                           (u32) STRUCT_TO_INT(device->status)));
120
121         return 0;
122 }
123
124 EXPORT_SYMBOL(acpi_bus_get_status);
125
126 /* --------------------------------------------------------------------------
127                                  Power Management
128    -------------------------------------------------------------------------- */
129
130 int acpi_bus_get_power(acpi_handle handle, int *state)
131 {
132         int result = 0;
133         acpi_status status = 0;
134         struct acpi_device *device = NULL;
135         unsigned long psc = 0;
136
137
138         result = acpi_bus_get_device(handle, &device);
139         if (result)
140                 return result;
141
142         *state = ACPI_STATE_UNKNOWN;
143
144         if (!device->flags.power_manageable) {
145                 /* TBD: Non-recursive algorithm for walking up hierarchy */
146                 if (device->parent)
147                         *state = device->parent->power.state;
148                 else
149                         *state = ACPI_STATE_D0;
150         } else {
151                 /*
152                  * Get the device's power state either directly (via _PSC) or
153                  * indirectly (via power resources).
154                  */
155                 if (device->power.flags.explicit_get) {
156                         status = acpi_evaluate_integer(device->handle, "_PSC",
157                                                        NULL, &psc);
158                         if (ACPI_FAILURE(status))
159                                 return -ENODEV;
160                         device->power.state = (int)psc;
161                 } else if (device->power.flags.power_resources) {
162                         result = acpi_power_get_inferred_state(device);
163                         if (result)
164                                 return result;
165                 }
166
167                 *state = device->power.state;
168         }
169
170         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
171                           device->pnp.bus_id, device->power.state));
172
173         return 0;
174 }
175
176 EXPORT_SYMBOL(acpi_bus_get_power);
177
178 int acpi_bus_set_power(acpi_handle handle, int state)
179 {
180         int result = 0;
181         acpi_status status = AE_OK;
182         struct acpi_device *device = NULL;
183         char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
184
185
186         result = acpi_bus_get_device(handle, &device);
187         if (result)
188                 return result;
189
190         if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
191                 return -EINVAL;
192
193         /* Make sure this is a valid target state */
194
195         if (!device->flags.power_manageable) {
196                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
197                                 device->dev.kobj.name));
198                 return -ENODEV;
199         }
200         /*
201          * Get device's current power state if it's unknown
202          * This means device power state isn't initialized or previous setting failed
203          */
204         if ((device->power.state == ACPI_STATE_UNKNOWN) || device->flags.force_power_state)
205                 acpi_bus_get_power(device->handle, &device->power.state);
206         if ((state == device->power.state) && !device->flags.force_power_state) {
207                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
208                                   state));
209                 return 0;
210         }
211
212         if (!device->power.states[state].flags.valid) {
213                 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
214                 return -ENODEV;
215         }
216         if (device->parent && (state < device->parent->power.state)) {
217                 printk(KERN_WARNING PREFIX
218                               "Cannot set device to a higher-powered"
219                               " state than parent\n");
220                 return -ENODEV;
221         }
222
223         /*
224          * Transition Power
225          * ----------------
226          * On transitions to a high-powered state we first apply power (via
227          * power resources) then evalute _PSx.  Conversly for transitions to
228          * a lower-powered state.
229          */
230         if (state < device->power.state) {
231                 if (device->power.flags.power_resources) {
232                         result = acpi_power_transition(device, state);
233                         if (result)
234                                 goto end;
235                 }
236                 if (device->power.states[state].flags.explicit_set) {
237                         status = acpi_evaluate_object(device->handle,
238                                                       object_name, NULL, NULL);
239                         if (ACPI_FAILURE(status)) {
240                                 result = -ENODEV;
241                                 goto end;
242                         }
243                 }
244         } else {
245                 if (device->power.states[state].flags.explicit_set) {
246                         status = acpi_evaluate_object(device->handle,
247                                                       object_name, NULL, NULL);
248                         if (ACPI_FAILURE(status)) {
249                                 result = -ENODEV;
250                                 goto end;
251                         }
252                 }
253                 if (device->power.flags.power_resources) {
254                         result = acpi_power_transition(device, state);
255                         if (result)
256                                 goto end;
257                 }
258         }
259
260       end:
261         if (result)
262                 printk(KERN_WARNING PREFIX
263                               "Transitioning device [%s] to D%d\n",
264                               device->pnp.bus_id, state);
265         else
266                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
267                                   "Device [%s] transitioned to D%d\n",
268                                   device->pnp.bus_id, state));
269
270         return result;
271 }
272
273 EXPORT_SYMBOL(acpi_bus_set_power);
274
275 /* --------------------------------------------------------------------------
276                                 Event Management
277    -------------------------------------------------------------------------- */
278
279 #ifdef CONFIG_ACPI_PROC_EVENT
280 static DEFINE_SPINLOCK(acpi_bus_event_lock);
281
282 LIST_HEAD(acpi_bus_event_list);
283 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
284
285 extern int event_is_open;
286
287 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
288 {
289         struct acpi_bus_event *event = NULL;
290         unsigned long flags = 0;
291
292
293         if (!device)
294                 return -EINVAL;
295
296         /* drop event on the floor if no one's listening */
297         if (!event_is_open)
298                 return 0;
299
300         event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
301         if (!event)
302                 return -ENOMEM;
303
304         strcpy(event->device_class, device->pnp.device_class);
305         strcpy(event->bus_id, device->pnp.bus_id);
306         event->type = type;
307         event->data = data;
308
309         spin_lock_irqsave(&acpi_bus_event_lock, flags);
310         list_add_tail(&event->node, &acpi_bus_event_list);
311         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
312
313         wake_up_interruptible(&acpi_bus_event_queue);
314
315         return 0;
316 }
317
318 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
319
320 int acpi_bus_receive_event(struct acpi_bus_event *event)
321 {
322         unsigned long flags = 0;
323         struct acpi_bus_event *entry = NULL;
324
325         DECLARE_WAITQUEUE(wait, current);
326
327
328         if (!event)
329                 return -EINVAL;
330
331         if (list_empty(&acpi_bus_event_list)) {
332
333                 set_current_state(TASK_INTERRUPTIBLE);
334                 add_wait_queue(&acpi_bus_event_queue, &wait);
335
336                 if (list_empty(&acpi_bus_event_list))
337                         schedule();
338
339                 remove_wait_queue(&acpi_bus_event_queue, &wait);
340                 set_current_state(TASK_RUNNING);
341
342                 if (signal_pending(current))
343                         return -ERESTARTSYS;
344         }
345
346         spin_lock_irqsave(&acpi_bus_event_lock, flags);
347         entry =
348             list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
349         if (entry)
350                 list_del(&entry->node);
351         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
352
353         if (!entry)
354                 return -ENODEV;
355
356         memcpy(event, entry, sizeof(struct acpi_bus_event));
357
358         kfree(entry);
359
360         return 0;
361 }
362
363 EXPORT_SYMBOL(acpi_bus_receive_event);
364 #endif  /* CONFIG_ACPI_PROC_EVENT */
365
366 /* --------------------------------------------------------------------------
367                              Notification Handling
368    -------------------------------------------------------------------------- */
369
370 static int
371 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
372 {
373         acpi_status status = 0;
374         struct acpi_device_status old_status;
375
376
377         if (!device)
378                 return -EINVAL;
379
380         if (status_changed)
381                 *status_changed = 0;
382
383         old_status = device->status;
384
385         /*
386          * Make sure this device's parent is present before we go about
387          * messing with the device.
388          */
389         if (device->parent && !device->parent->status.present) {
390                 device->status = device->parent->status;
391                 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
392                         if (status_changed)
393                                 *status_changed = 1;
394                 }
395                 return 0;
396         }
397
398         status = acpi_bus_get_status(device);
399         if (ACPI_FAILURE(status))
400                 return -ENODEV;
401
402         if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
403                 return 0;
404
405         if (status_changed)
406                 *status_changed = 1;
407
408         /*
409          * Device Insertion/Removal
410          */
411         if ((device->status.present) && !(old_status.present)) {
412                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
413                 /* TBD: Handle device insertion */
414         } else if (!(device->status.present) && (old_status.present)) {
415                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
416                 /* TBD: Handle device removal */
417         }
418
419         return 0;
420 }
421
422 static int acpi_bus_check_scope(struct acpi_device *device)
423 {
424         int result = 0;
425         int status_changed = 0;
426
427
428         if (!device)
429                 return -EINVAL;
430
431         /* Status Change? */
432         result = acpi_bus_check_device(device, &status_changed);
433         if (result)
434                 return result;
435
436         if (!status_changed)
437                 return 0;
438
439         /*
440          * TBD: Enumerate child devices within this device's scope and
441          *       run acpi_bus_check_device()'s on them.
442          */
443
444         return 0;
445 }
446
447 /**
448  * acpi_bus_notify
449  * ---------------
450  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
451  */
452 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
453 {
454         int result = 0;
455         struct acpi_device *device = NULL;
456
457
458         if (acpi_bus_get_device(handle, &device))
459                 return;
460
461         switch (type) {
462
463         case ACPI_NOTIFY_BUS_CHECK:
464                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
465                                   "Received BUS CHECK notification for device [%s]\n",
466                                   device->pnp.bus_id));
467                 result = acpi_bus_check_scope(device);
468                 /*
469                  * TBD: We'll need to outsource certain events to non-ACPI
470                  *      drivers via the device manager (device.c).
471                  */
472                 break;
473
474         case ACPI_NOTIFY_DEVICE_CHECK:
475                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
476                                   "Received DEVICE CHECK notification for device [%s]\n",
477                                   device->pnp.bus_id));
478                 result = acpi_bus_check_device(device, NULL);
479                 /*
480                  * TBD: We'll need to outsource certain events to non-ACPI
481                  *      drivers via the device manager (device.c).
482                  */
483                 break;
484
485         case ACPI_NOTIFY_DEVICE_WAKE:
486                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
487                                   "Received DEVICE WAKE notification for device [%s]\n",
488                                   device->pnp.bus_id));
489                 /* TBD */
490                 break;
491
492         case ACPI_NOTIFY_EJECT_REQUEST:
493                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
494                                   "Received EJECT REQUEST notification for device [%s]\n",
495                                   device->pnp.bus_id));
496                 /* TBD */
497                 break;
498
499         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
500                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
501                                   "Received DEVICE CHECK LIGHT notification for device [%s]\n",
502                                   device->pnp.bus_id));
503                 /* TBD: Exactly what does 'light' mean? */
504                 break;
505
506         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
507                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
508                                   "Received FREQUENCY MISMATCH notification for device [%s]\n",
509                                   device->pnp.bus_id));
510                 /* TBD */
511                 break;
512
513         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
514                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
515                                   "Received BUS MODE MISMATCH notification for device [%s]\n",
516                                   device->pnp.bus_id));
517                 /* TBD */
518                 break;
519
520         case ACPI_NOTIFY_POWER_FAULT:
521                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
522                                   "Received POWER FAULT notification for device [%s]\n",
523                                   device->pnp.bus_id));
524                 /* TBD */
525                 break;
526
527         default:
528                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
529                                   "Received unknown/unsupported notification [%08x]\n",
530                                   type));
531                 break;
532         }
533
534         return;
535 }
536
537 /* --------------------------------------------------------------------------
538                              Initialization/Cleanup
539    -------------------------------------------------------------------------- */
540
541 static int __init acpi_bus_init_irq(void)
542 {
543         acpi_status status = AE_OK;
544         union acpi_object arg = { ACPI_TYPE_INTEGER };
545         struct acpi_object_list arg_list = { 1, &arg };
546         char *message = NULL;
547
548
549         /*
550          * Let the system know what interrupt model we are using by
551          * evaluating the \_PIC object, if exists.
552          */
553
554         switch (acpi_irq_model) {
555         case ACPI_IRQ_MODEL_PIC:
556                 message = "PIC";
557                 break;
558         case ACPI_IRQ_MODEL_IOAPIC:
559                 message = "IOAPIC";
560                 break;
561         case ACPI_IRQ_MODEL_IOSAPIC:
562                 message = "IOSAPIC";
563                 break;
564         case ACPI_IRQ_MODEL_PLATFORM:
565                 message = "platform specific model";
566                 break;
567         default:
568                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
569                 return -ENODEV;
570         }
571
572         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
573
574         arg.integer.value = acpi_irq_model;
575
576         status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
577         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
578                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
579                 return -ENODEV;
580         }
581
582         return 0;
583 }
584
585 acpi_native_uint acpi_gbl_permanent_mmap;
586
587
588 void __init acpi_early_init(void)
589 {
590         acpi_status status = AE_OK;
591
592         if (acpi_disabled)
593                 return;
594
595         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
596
597         /* enable workarounds, unless strict ACPI spec. compliance */
598         if (!acpi_strict)
599                 acpi_gbl_enable_interpreter_slack = TRUE;
600
601         acpi_gbl_permanent_mmap = 1;
602
603         status = acpi_reallocate_root_table();
604         if (ACPI_FAILURE(status)) {
605                 printk(KERN_ERR PREFIX
606                        "Unable to reallocate ACPI tables\n");
607                 goto error0;
608         }
609
610         status = acpi_initialize_subsystem();
611         if (ACPI_FAILURE(status)) {
612                 printk(KERN_ERR PREFIX
613                        "Unable to initialize the ACPI Interpreter\n");
614                 goto error0;
615         }
616
617         status = acpi_load_tables();
618         if (ACPI_FAILURE(status)) {
619                 printk(KERN_ERR PREFIX
620                        "Unable to load the System Description Tables\n");
621                 goto error0;
622         }
623
624 #ifdef CONFIG_X86
625         if (!acpi_ioapic) {
626                 extern u8 acpi_sci_flags;
627
628                 /* compatible (0) means level (3) */
629                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
630                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
631                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
632                 }
633                 /* Set PIC-mode SCI trigger type */
634                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
635                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
636         } else {
637                 extern int acpi_sci_override_gsi;
638                 /*
639                  * now that acpi_gbl_FADT is initialized,
640                  * update it with result from INT_SRC_OVR parsing
641                  */
642                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
643         }
644 #endif
645
646         status =
647             acpi_enable_subsystem(~
648                                   (ACPI_NO_HARDWARE_INIT |
649                                    ACPI_NO_ACPI_ENABLE));
650         if (ACPI_FAILURE(status)) {
651                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
652                 goto error0;
653         }
654
655         return;
656
657       error0:
658         disable_acpi();
659         return;
660 }
661
662 static int __init acpi_bus_init(void)
663 {
664         int result = 0;
665         acpi_status status = AE_OK;
666         extern acpi_status acpi_os_initialize1(void);
667
668
669         status = acpi_os_initialize1();
670
671         status =
672             acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
673         if (ACPI_FAILURE(status)) {
674                 printk(KERN_ERR PREFIX
675                        "Unable to start the ACPI Interpreter\n");
676                 goto error1;
677         }
678
679         if (ACPI_FAILURE(status)) {
680                 printk(KERN_ERR PREFIX
681                        "Unable to initialize ACPI OS objects\n");
682                 goto error1;
683         }
684 #ifdef CONFIG_ACPI_EC
685         /*
686          * ACPI 2.0 requires the EC driver to be loaded and work before
687          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
688          * is called).
689          *
690          * This is accomplished by looking for the ECDT table, and getting
691          * the EC parameters out of that.
692          */
693         status = acpi_ec_ecdt_probe();
694         /* Ignore result. Not having an ECDT is not fatal. */
695 #endif
696
697         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
698         if (ACPI_FAILURE(status)) {
699                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
700                 goto error1;
701         }
702
703         printk(KERN_INFO PREFIX "Interpreter enabled\n");
704
705         /* Initialize sleep structures */
706         acpi_sleep_init();
707
708         /*
709          * Get the system interrupt model and evaluate \_PIC.
710          */
711         result = acpi_bus_init_irq();
712         if (result)
713                 goto error1;
714
715         /*
716          * Register the for all standard device notifications.
717          */
718         status =
719             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
720                                         &acpi_bus_notify, NULL);
721         if (ACPI_FAILURE(status)) {
722                 printk(KERN_ERR PREFIX
723                        "Unable to register for device notifications\n");
724                 goto error1;
725         }
726
727         /*
728          * Create the top ACPI proc directory
729          */
730         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
731
732         return 0;
733
734         /* Mimic structured exception handling */
735       error1:
736         acpi_terminate();
737         return -ENODEV;
738 }
739
740 decl_subsys(acpi, NULL, NULL);
741
742 static int __init acpi_init(void)
743 {
744         int result = 0;
745
746
747         if (acpi_disabled) {
748                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
749                 return -ENODEV;
750         }
751
752         result = firmware_register(&acpi_subsys);
753         if (result < 0)
754                 printk(KERN_WARNING "%s: firmware_register error: %d\n",
755                         __FUNCTION__, result);
756
757         result = acpi_bus_init();
758
759         if (!result) {
760 #ifdef CONFIG_PM_LEGACY
761                 if (!PM_IS_ACTIVE())
762                         pm_active = 1;
763                 else {
764                         printk(KERN_INFO PREFIX
765                                "APM is already active, exiting\n");
766                         disable_acpi();
767                         result = -ENODEV;
768                 }
769 #endif
770         } else
771                 disable_acpi();
772
773         return result;
774 }
775
776 subsys_initcall(acpi_init);