Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
[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                                 kobject_name(&device->dev.kobj)));
198                 return -ENODEV;
199         }
200         /*
201          * Get device's current power state
202          */
203         acpi_bus_get_power(device->handle, &device->power.state);
204         if (state == device->power.state) {
205                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
206                                   state));
207                 return 0;
208         }
209
210         if (!device->power.states[state].flags.valid) {
211                 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
212                 return -ENODEV;
213         }
214         if (device->parent && (state < device->parent->power.state)) {
215                 printk(KERN_WARNING PREFIX
216                               "Cannot set device to a higher-powered"
217                               " state than parent\n");
218                 return -ENODEV;
219         }
220
221         /*
222          * Transition Power
223          * ----------------
224          * On transitions to a high-powered state we first apply power (via
225          * power resources) then evalute _PSx.  Conversly for transitions to
226          * a lower-powered state.
227          */
228         if (state < device->power.state) {
229                 if (device->power.flags.power_resources) {
230                         result = acpi_power_transition(device, state);
231                         if (result)
232                                 goto end;
233                 }
234                 if (device->power.states[state].flags.explicit_set) {
235                         status = acpi_evaluate_object(device->handle,
236                                                       object_name, NULL, NULL);
237                         if (ACPI_FAILURE(status)) {
238                                 result = -ENODEV;
239                                 goto end;
240                         }
241                 }
242         } else {
243                 if (device->power.states[state].flags.explicit_set) {
244                         status = acpi_evaluate_object(device->handle,
245                                                       object_name, NULL, NULL);
246                         if (ACPI_FAILURE(status)) {
247                                 result = -ENODEV;
248                                 goto end;
249                         }
250                 }
251                 if (device->power.flags.power_resources) {
252                         result = acpi_power_transition(device, state);
253                         if (result)
254                                 goto end;
255                 }
256         }
257
258       end:
259         if (result)
260                 printk(KERN_WARNING PREFIX
261                               "Transitioning device [%s] to D%d\n",
262                               device->pnp.bus_id, state);
263         else {
264                 device->power.state = state;
265                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
266                                   "Device [%s] transitioned to D%d\n",
267                                   device->pnp.bus_id, state));
268         }
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_event4(const char *device_class, const char *bus_id, u8 type, int data)
288 {
289         struct acpi_bus_event *event;
290         unsigned long flags = 0;
291
292         /* drop event on the floor if no one's listening */
293         if (!event_is_open)
294                 return 0;
295
296         event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
297         if (!event)
298                 return -ENOMEM;
299
300         strcpy(event->device_class, device_class);
301         strcpy(event->bus_id, bus_id);
302         event->type = type;
303         event->data = data;
304
305         spin_lock_irqsave(&acpi_bus_event_lock, flags);
306         list_add_tail(&event->node, &acpi_bus_event_list);
307         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
308
309         wake_up_interruptible(&acpi_bus_event_queue);
310
311         return 0;
312
313 }
314
315 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
316
317 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
318 {
319         if (!device)
320                 return -EINVAL;
321         return acpi_bus_generate_proc_event4(device->pnp.device_class,
322                                              device->pnp.bus_id, type, data);
323 }
324
325 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
326
327 int acpi_bus_receive_event(struct acpi_bus_event *event)
328 {
329         unsigned long flags = 0;
330         struct acpi_bus_event *entry = NULL;
331
332         DECLARE_WAITQUEUE(wait, current);
333
334
335         if (!event)
336                 return -EINVAL;
337
338         if (list_empty(&acpi_bus_event_list)) {
339
340                 set_current_state(TASK_INTERRUPTIBLE);
341                 add_wait_queue(&acpi_bus_event_queue, &wait);
342
343                 if (list_empty(&acpi_bus_event_list))
344                         schedule();
345
346                 remove_wait_queue(&acpi_bus_event_queue, &wait);
347                 set_current_state(TASK_RUNNING);
348
349                 if (signal_pending(current))
350                         return -ERESTARTSYS;
351         }
352
353         spin_lock_irqsave(&acpi_bus_event_lock, flags);
354         entry =
355             list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
356         if (entry)
357                 list_del(&entry->node);
358         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
359
360         if (!entry)
361                 return -ENODEV;
362
363         memcpy(event, entry, sizeof(struct acpi_bus_event));
364
365         kfree(entry);
366
367         return 0;
368 }
369
370 EXPORT_SYMBOL(acpi_bus_receive_event);
371 #endif  /* CONFIG_ACPI_PROC_EVENT */
372
373 /* --------------------------------------------------------------------------
374                              Notification Handling
375    -------------------------------------------------------------------------- */
376
377 static int
378 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
379 {
380         acpi_status status = 0;
381         struct acpi_device_status old_status;
382
383
384         if (!device)
385                 return -EINVAL;
386
387         if (status_changed)
388                 *status_changed = 0;
389
390         old_status = device->status;
391
392         /*
393          * Make sure this device's parent is present before we go about
394          * messing with the device.
395          */
396         if (device->parent && !device->parent->status.present) {
397                 device->status = device->parent->status;
398                 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
399                         if (status_changed)
400                                 *status_changed = 1;
401                 }
402                 return 0;
403         }
404
405         status = acpi_bus_get_status(device);
406         if (ACPI_FAILURE(status))
407                 return -ENODEV;
408
409         if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
410                 return 0;
411
412         if (status_changed)
413                 *status_changed = 1;
414
415         /*
416          * Device Insertion/Removal
417          */
418         if ((device->status.present) && !(old_status.present)) {
419                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
420                 /* TBD: Handle device insertion */
421         } else if (!(device->status.present) && (old_status.present)) {
422                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
423                 /* TBD: Handle device removal */
424         }
425
426         return 0;
427 }
428
429 static int acpi_bus_check_scope(struct acpi_device *device)
430 {
431         int result = 0;
432         int status_changed = 0;
433
434
435         if (!device)
436                 return -EINVAL;
437
438         /* Status Change? */
439         result = acpi_bus_check_device(device, &status_changed);
440         if (result)
441                 return result;
442
443         if (!status_changed)
444                 return 0;
445
446         /*
447          * TBD: Enumerate child devices within this device's scope and
448          *       run acpi_bus_check_device()'s on them.
449          */
450
451         return 0;
452 }
453
454 /**
455  * acpi_bus_notify
456  * ---------------
457  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
458  */
459 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
460 {
461         int result = 0;
462         struct acpi_device *device = NULL;
463
464
465         if (acpi_bus_get_device(handle, &device))
466                 return;
467
468         switch (type) {
469
470         case ACPI_NOTIFY_BUS_CHECK:
471                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
472                                   "Received BUS CHECK notification for device [%s]\n",
473                                   device->pnp.bus_id));
474                 result = acpi_bus_check_scope(device);
475                 /*
476                  * TBD: We'll need to outsource certain events to non-ACPI
477                  *      drivers via the device manager (device.c).
478                  */
479                 break;
480
481         case ACPI_NOTIFY_DEVICE_CHECK:
482                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
483                                   "Received DEVICE CHECK notification for device [%s]\n",
484                                   device->pnp.bus_id));
485                 result = acpi_bus_check_device(device, NULL);
486                 /*
487                  * TBD: We'll need to outsource certain events to non-ACPI
488                  *      drivers via the device manager (device.c).
489                  */
490                 break;
491
492         case ACPI_NOTIFY_DEVICE_WAKE:
493                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
494                                   "Received DEVICE WAKE notification for device [%s]\n",
495                                   device->pnp.bus_id));
496                 /* TBD */
497                 break;
498
499         case ACPI_NOTIFY_EJECT_REQUEST:
500                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
501                                   "Received EJECT REQUEST notification for device [%s]\n",
502                                   device->pnp.bus_id));
503                 /* TBD */
504                 break;
505
506         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
507                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
508                                   "Received DEVICE CHECK LIGHT notification for device [%s]\n",
509                                   device->pnp.bus_id));
510                 /* TBD: Exactly what does 'light' mean? */
511                 break;
512
513         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
514                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
515                                   "Received FREQUENCY MISMATCH notification for device [%s]\n",
516                                   device->pnp.bus_id));
517                 /* TBD */
518                 break;
519
520         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
521                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
522                                   "Received BUS MODE MISMATCH notification for device [%s]\n",
523                                   device->pnp.bus_id));
524                 /* TBD */
525                 break;
526
527         case ACPI_NOTIFY_POWER_FAULT:
528                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
529                                   "Received POWER FAULT notification for device [%s]\n",
530                                   device->pnp.bus_id));
531                 /* TBD */
532                 break;
533
534         default:
535                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
536                                   "Received unknown/unsupported notification [%08x]\n",
537                                   type));
538                 break;
539         }
540
541         return;
542 }
543
544 /* --------------------------------------------------------------------------
545                              Initialization/Cleanup
546    -------------------------------------------------------------------------- */
547
548 static int __init acpi_bus_init_irq(void)
549 {
550         acpi_status status = AE_OK;
551         union acpi_object arg = { ACPI_TYPE_INTEGER };
552         struct acpi_object_list arg_list = { 1, &arg };
553         char *message = NULL;
554
555
556         /*
557          * Let the system know what interrupt model we are using by
558          * evaluating the \_PIC object, if exists.
559          */
560
561         switch (acpi_irq_model) {
562         case ACPI_IRQ_MODEL_PIC:
563                 message = "PIC";
564                 break;
565         case ACPI_IRQ_MODEL_IOAPIC:
566                 message = "IOAPIC";
567                 break;
568         case ACPI_IRQ_MODEL_IOSAPIC:
569                 message = "IOSAPIC";
570                 break;
571         case ACPI_IRQ_MODEL_PLATFORM:
572                 message = "platform specific model";
573                 break;
574         default:
575                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
576                 return -ENODEV;
577         }
578
579         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
580
581         arg.integer.value = acpi_irq_model;
582
583         status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
584         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
585                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
586                 return -ENODEV;
587         }
588
589         return 0;
590 }
591
592 acpi_native_uint acpi_gbl_permanent_mmap;
593
594
595 void __init acpi_early_init(void)
596 {
597         acpi_status status = AE_OK;
598
599         if (acpi_disabled)
600                 return;
601
602         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
603
604         /* enable workarounds, unless strict ACPI spec. compliance */
605         if (!acpi_strict)
606                 acpi_gbl_enable_interpreter_slack = TRUE;
607
608         acpi_gbl_permanent_mmap = 1;
609
610         status = acpi_reallocate_root_table();
611         if (ACPI_FAILURE(status)) {
612                 printk(KERN_ERR PREFIX
613                        "Unable to reallocate ACPI tables\n");
614                 goto error0;
615         }
616
617         status = acpi_initialize_subsystem();
618         if (ACPI_FAILURE(status)) {
619                 printk(KERN_ERR PREFIX
620                        "Unable to initialize the ACPI Interpreter\n");
621                 goto error0;
622         }
623
624         status = acpi_load_tables();
625         if (ACPI_FAILURE(status)) {
626                 printk(KERN_ERR PREFIX
627                        "Unable to load the System Description Tables\n");
628                 goto error0;
629         }
630
631 #ifdef CONFIG_X86
632         if (!acpi_ioapic) {
633                 extern u8 acpi_sci_flags;
634
635                 /* compatible (0) means level (3) */
636                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
637                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
638                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
639                 }
640                 /* Set PIC-mode SCI trigger type */
641                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
642                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
643         } else {
644                 extern int acpi_sci_override_gsi;
645                 /*
646                  * now that acpi_gbl_FADT is initialized,
647                  * update it with result from INT_SRC_OVR parsing
648                  */
649                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
650         }
651 #endif
652
653         status =
654             acpi_enable_subsystem(~
655                                   (ACPI_NO_HARDWARE_INIT |
656                                    ACPI_NO_ACPI_ENABLE));
657         if (ACPI_FAILURE(status)) {
658                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
659                 goto error0;
660         }
661
662         return;
663
664       error0:
665         disable_acpi();
666         return;
667 }
668
669 static int __init acpi_bus_init(void)
670 {
671         int result = 0;
672         acpi_status status = AE_OK;
673         extern acpi_status acpi_os_initialize1(void);
674
675
676         status = acpi_os_initialize1();
677
678         status =
679             acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
680         if (ACPI_FAILURE(status)) {
681                 printk(KERN_ERR PREFIX
682                        "Unable to start the ACPI Interpreter\n");
683                 goto error1;
684         }
685
686         if (ACPI_FAILURE(status)) {
687                 printk(KERN_ERR PREFIX
688                        "Unable to initialize ACPI OS objects\n");
689                 goto error1;
690         }
691 #ifdef CONFIG_ACPI_EC
692         /*
693          * ACPI 2.0 requires the EC driver to be loaded and work before
694          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
695          * is called).
696          *
697          * This is accomplished by looking for the ECDT table, and getting
698          * the EC parameters out of that.
699          */
700         status = acpi_ec_ecdt_probe();
701         /* Ignore result. Not having an ECDT is not fatal. */
702 #endif
703
704         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
705         if (ACPI_FAILURE(status)) {
706                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
707                 goto error1;
708         }
709
710         printk(KERN_INFO PREFIX "Interpreter enabled\n");
711
712         /* Initialize sleep structures */
713         acpi_sleep_init();
714
715         /*
716          * Get the system interrupt model and evaluate \_PIC.
717          */
718         result = acpi_bus_init_irq();
719         if (result)
720                 goto error1;
721
722         /*
723          * Register the for all standard device notifications.
724          */
725         status =
726             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
727                                         &acpi_bus_notify, NULL);
728         if (ACPI_FAILURE(status)) {
729                 printk(KERN_ERR PREFIX
730                        "Unable to register for device notifications\n");
731                 goto error1;
732         }
733
734         /*
735          * Create the top ACPI proc directory
736          */
737         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
738
739         return 0;
740
741         /* Mimic structured exception handling */
742       error1:
743         acpi_terminate();
744         return -ENODEV;
745 }
746
747 decl_subsys(acpi, NULL, NULL);
748
749 static int __init acpi_init(void)
750 {
751         int result = 0;
752
753
754         if (acpi_disabled) {
755                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
756                 return -ENODEV;
757         }
758
759         result = firmware_register(&acpi_subsys);
760         if (result < 0)
761                 printk(KERN_WARNING "%s: firmware_register error: %d\n",
762                         __FUNCTION__, result);
763
764         result = acpi_bus_init();
765
766         if (!result) {
767 #ifdef CONFIG_PM_LEGACY
768                 if (!PM_IS_ACTIVE())
769                         pm_active = 1;
770                 else {
771                         printk(KERN_INFO PREFIX
772                                "APM is already active, exiting\n");
773                         disable_acpi();
774                         result = -ENODEV;
775                 }
776 #endif
777         } else
778                 disable_acpi();
779
780         return result;
781 }
782
783 subsys_initcall(acpi_init);