Pull bugzilla-8346 into release branch
[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 static DEFINE_SPINLOCK(acpi_bus_event_lock);
280
281 LIST_HEAD(acpi_bus_event_list);
282 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
283
284 extern int event_is_open;
285
286 int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
287 {
288         struct acpi_bus_event *event = NULL;
289         unsigned long flags = 0;
290
291
292         if (!device)
293                 return -EINVAL;
294
295         /* drop event on the floor if no one's listening */
296         if (!event_is_open)
297                 return 0;
298
299         event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
300         if (!event)
301                 return -ENOMEM;
302
303         strcpy(event->device_class, device->pnp.device_class);
304         strcpy(event->bus_id, device->pnp.bus_id);
305         event->type = type;
306         event->data = data;
307
308         spin_lock_irqsave(&acpi_bus_event_lock, flags);
309         list_add_tail(&event->node, &acpi_bus_event_list);
310         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
311
312         wake_up_interruptible(&acpi_bus_event_queue);
313
314         return 0;
315 }
316
317 EXPORT_SYMBOL(acpi_bus_generate_event);
318
319 int acpi_bus_receive_event(struct acpi_bus_event *event)
320 {
321         unsigned long flags = 0;
322         struct acpi_bus_event *entry = NULL;
323
324         DECLARE_WAITQUEUE(wait, current);
325
326
327         if (!event)
328                 return -EINVAL;
329
330         if (list_empty(&acpi_bus_event_list)) {
331
332                 set_current_state(TASK_INTERRUPTIBLE);
333                 add_wait_queue(&acpi_bus_event_queue, &wait);
334
335                 if (list_empty(&acpi_bus_event_list))
336                         schedule();
337
338                 remove_wait_queue(&acpi_bus_event_queue, &wait);
339                 set_current_state(TASK_RUNNING);
340
341                 if (signal_pending(current))
342                         return -ERESTARTSYS;
343         }
344
345         spin_lock_irqsave(&acpi_bus_event_lock, flags);
346         entry =
347             list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
348         if (entry)
349                 list_del(&entry->node);
350         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
351
352         if (!entry)
353                 return -ENODEV;
354
355         memcpy(event, entry, sizeof(struct acpi_bus_event));
356
357         kfree(entry);
358
359         return 0;
360 }
361
362 EXPORT_SYMBOL(acpi_bus_receive_event);
363
364 /* --------------------------------------------------------------------------
365                              Notification Handling
366    -------------------------------------------------------------------------- */
367
368 static int
369 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
370 {
371         acpi_status status = 0;
372         struct acpi_device_status old_status;
373
374
375         if (!device)
376                 return -EINVAL;
377
378         if (status_changed)
379                 *status_changed = 0;
380
381         old_status = device->status;
382
383         /*
384          * Make sure this device's parent is present before we go about
385          * messing with the device.
386          */
387         if (device->parent && !device->parent->status.present) {
388                 device->status = device->parent->status;
389                 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
390                         if (status_changed)
391                                 *status_changed = 1;
392                 }
393                 return 0;
394         }
395
396         status = acpi_bus_get_status(device);
397         if (ACPI_FAILURE(status))
398                 return -ENODEV;
399
400         if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
401                 return 0;
402
403         if (status_changed)
404                 *status_changed = 1;
405
406         /*
407          * Device Insertion/Removal
408          */
409         if ((device->status.present) && !(old_status.present)) {
410                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
411                 /* TBD: Handle device insertion */
412         } else if (!(device->status.present) && (old_status.present)) {
413                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
414                 /* TBD: Handle device removal */
415         }
416
417         return 0;
418 }
419
420 static int acpi_bus_check_scope(struct acpi_device *device)
421 {
422         int result = 0;
423         int status_changed = 0;
424
425
426         if (!device)
427                 return -EINVAL;
428
429         /* Status Change? */
430         result = acpi_bus_check_device(device, &status_changed);
431         if (result)
432                 return result;
433
434         if (!status_changed)
435                 return 0;
436
437         /*
438          * TBD: Enumerate child devices within this device's scope and
439          *       run acpi_bus_check_device()'s on them.
440          */
441
442         return 0;
443 }
444
445 /**
446  * acpi_bus_notify
447  * ---------------
448  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
449  */
450 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
451 {
452         int result = 0;
453         struct acpi_device *device = NULL;
454
455
456         if (acpi_bus_get_device(handle, &device))
457                 return;
458
459         switch (type) {
460
461         case ACPI_NOTIFY_BUS_CHECK:
462                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
463                                   "Received BUS CHECK notification for device [%s]\n",
464                                   device->pnp.bus_id));
465                 result = acpi_bus_check_scope(device);
466                 /*
467                  * TBD: We'll need to outsource certain events to non-ACPI
468                  *      drivers via the device manager (device.c).
469                  */
470                 break;
471
472         case ACPI_NOTIFY_DEVICE_CHECK:
473                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
474                                   "Received DEVICE CHECK notification for device [%s]\n",
475                                   device->pnp.bus_id));
476                 result = acpi_bus_check_device(device, NULL);
477                 /*
478                  * TBD: We'll need to outsource certain events to non-ACPI
479                  *      drivers via the device manager (device.c).
480                  */
481                 break;
482
483         case ACPI_NOTIFY_DEVICE_WAKE:
484                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
485                                   "Received DEVICE WAKE notification for device [%s]\n",
486                                   device->pnp.bus_id));
487                 /* TBD */
488                 break;
489
490         case ACPI_NOTIFY_EJECT_REQUEST:
491                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
492                                   "Received EJECT REQUEST notification for device [%s]\n",
493                                   device->pnp.bus_id));
494                 /* TBD */
495                 break;
496
497         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
498                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
499                                   "Received DEVICE CHECK LIGHT notification for device [%s]\n",
500                                   device->pnp.bus_id));
501                 /* TBD: Exactly what does 'light' mean? */
502                 break;
503
504         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
505                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
506                                   "Received FREQUENCY MISMATCH notification for device [%s]\n",
507                                   device->pnp.bus_id));
508                 /* TBD */
509                 break;
510
511         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
512                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
513                                   "Received BUS MODE MISMATCH notification for device [%s]\n",
514                                   device->pnp.bus_id));
515                 /* TBD */
516                 break;
517
518         case ACPI_NOTIFY_POWER_FAULT:
519                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
520                                   "Received POWER FAULT notification for device [%s]\n",
521                                   device->pnp.bus_id));
522                 /* TBD */
523                 break;
524
525         default:
526                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
527                                   "Received unknown/unsupported notification [%08x]\n",
528                                   type));
529                 break;
530         }
531
532         return;
533 }
534
535 /* --------------------------------------------------------------------------
536                              Initialization/Cleanup
537    -------------------------------------------------------------------------- */
538
539 static int __init acpi_bus_init_irq(void)
540 {
541         acpi_status status = AE_OK;
542         union acpi_object arg = { ACPI_TYPE_INTEGER };
543         struct acpi_object_list arg_list = { 1, &arg };
544         char *message = NULL;
545
546
547         /*
548          * Let the system know what interrupt model we are using by
549          * evaluating the \_PIC object, if exists.
550          */
551
552         switch (acpi_irq_model) {
553         case ACPI_IRQ_MODEL_PIC:
554                 message = "PIC";
555                 break;
556         case ACPI_IRQ_MODEL_IOAPIC:
557                 message = "IOAPIC";
558                 break;
559         case ACPI_IRQ_MODEL_IOSAPIC:
560                 message = "IOSAPIC";
561                 break;
562         case ACPI_IRQ_MODEL_PLATFORM:
563                 message = "platform specific model";
564                 break;
565         default:
566                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
567                 return -ENODEV;
568         }
569
570         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
571
572         arg.integer.value = acpi_irq_model;
573
574         status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
575         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
576                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
577                 return -ENODEV;
578         }
579
580         return 0;
581 }
582
583 acpi_native_uint acpi_gbl_permanent_mmap;
584
585
586 void __init acpi_early_init(void)
587 {
588         acpi_status status = AE_OK;
589
590         if (acpi_disabled)
591                 return;
592
593         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
594
595         /* enable workarounds, unless strict ACPI spec. compliance */
596         if (!acpi_strict)
597                 acpi_gbl_enable_interpreter_slack = TRUE;
598
599         acpi_gbl_permanent_mmap = 1;
600
601         status = acpi_reallocate_root_table();
602         if (ACPI_FAILURE(status)) {
603                 printk(KERN_ERR PREFIX
604                        "Unable to reallocate ACPI tables\n");
605                 goto error0;
606         }
607
608         status = acpi_initialize_subsystem();
609         if (ACPI_FAILURE(status)) {
610                 printk(KERN_ERR PREFIX
611                        "Unable to initialize the ACPI Interpreter\n");
612                 goto error0;
613         }
614
615         status = acpi_load_tables();
616         if (ACPI_FAILURE(status)) {
617                 printk(KERN_ERR PREFIX
618                        "Unable to load the System Description Tables\n");
619                 goto error0;
620         }
621
622 #ifdef CONFIG_X86
623         if (!acpi_ioapic) {
624                 extern u8 acpi_sci_flags;
625
626                 /* compatible (0) means level (3) */
627                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
628                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
629                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
630                 }
631                 /* Set PIC-mode SCI trigger type */
632                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
633                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
634         } else {
635                 extern int acpi_sci_override_gsi;
636                 /*
637                  * now that acpi_gbl_FADT is initialized,
638                  * update it with result from INT_SRC_OVR parsing
639                  */
640                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
641         }
642 #endif
643
644         status =
645             acpi_enable_subsystem(~
646                                   (ACPI_NO_HARDWARE_INIT |
647                                    ACPI_NO_ACPI_ENABLE));
648         if (ACPI_FAILURE(status)) {
649                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
650                 goto error0;
651         }
652
653         return;
654
655       error0:
656         disable_acpi();
657         return;
658 }
659
660 static int __init acpi_bus_init(void)
661 {
662         int result = 0;
663         acpi_status status = AE_OK;
664         extern acpi_status acpi_os_initialize1(void);
665
666
667         status = acpi_os_initialize1();
668
669         status =
670             acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
671         if (ACPI_FAILURE(status)) {
672                 printk(KERN_ERR PREFIX
673                        "Unable to start the ACPI Interpreter\n");
674                 goto error1;
675         }
676
677         if (ACPI_FAILURE(status)) {
678                 printk(KERN_ERR PREFIX
679                        "Unable to initialize ACPI OS objects\n");
680                 goto error1;
681         }
682 #ifdef CONFIG_ACPI_EC
683         /*
684          * ACPI 2.0 requires the EC driver to be loaded and work before
685          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
686          * is called).
687          *
688          * This is accomplished by looking for the ECDT table, and getting
689          * the EC parameters out of that.
690          */
691         status = acpi_ec_ecdt_probe();
692         /* Ignore result. Not having an ECDT is not fatal. */
693 #endif
694
695         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
696         if (ACPI_FAILURE(status)) {
697                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
698                 goto error1;
699         }
700
701         printk(KERN_INFO PREFIX "Interpreter enabled\n");
702
703         /* Initialize sleep structures */
704         acpi_sleep_init();
705
706         /*
707          * Get the system interrupt model and evaluate \_PIC.
708          */
709         result = acpi_bus_init_irq();
710         if (result)
711                 goto error1;
712
713         /*
714          * Register the for all standard device notifications.
715          */
716         status =
717             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
718                                         &acpi_bus_notify, NULL);
719         if (ACPI_FAILURE(status)) {
720                 printk(KERN_ERR PREFIX
721                        "Unable to register for device notifications\n");
722                 goto error1;
723         }
724
725         /*
726          * Create the top ACPI proc directory
727          */
728         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
729
730         return 0;
731
732         /* Mimic structured exception handling */
733       error1:
734         acpi_terminate();
735         return -ENODEV;
736 }
737
738 decl_subsys(acpi, NULL, NULL);
739
740 static int __init acpi_init(void)
741 {
742         int result = 0;
743
744
745         if (acpi_disabled) {
746                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
747                 return -ENODEV;
748         }
749
750         result = firmware_register(&acpi_subsys);
751         if (result < 0)
752                 printk(KERN_WARNING "%s: firmware_register error: %d\n",
753                         __FUNCTION__, result);
754
755         result = acpi_bus_init();
756
757         if (!result) {
758 #ifdef CONFIG_PM_LEGACY
759                 if (!PM_IS_ACTIVE())
760                         pm_active = 1;
761                 else {
762                         printk(KERN_INFO PREFIX
763                                "APM is already active, exiting\n");
764                         disable_acpi();
765                         result = -ENODEV;
766                 }
767 #endif
768         } else
769                 disable_acpi();
770
771         return result;
772 }
773
774 subsys_initcall(acpi_init);