Revert "ACPI: Fan: Drop force_power_state acpi_device option"
[linux-2.6.git] / 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/device.h>
33 #include <linux/proc_fs.h>
34 #ifdef CONFIG_X86
35 #include <asm/mpspec.h>
36 #endif
37 #include <acpi/acpi_bus.h>
38 #include <acpi/acpi_drivers.h>
39
40 #define _COMPONENT              ACPI_BUS_COMPONENT
41 ACPI_MODULE_NAME("bus");
42 #ifdef  CONFIG_X86
43 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
44 #endif
45
46 struct acpi_device *acpi_root;
47 struct proc_dir_entry *acpi_root_dir;
48 EXPORT_SYMBOL(acpi_root_dir);
49
50 #define STRUCT_TO_INT(s)        (*((int*)&s))
51
52 /* --------------------------------------------------------------------------
53                                 Device Management
54    -------------------------------------------------------------------------- */
55
56 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
57 {
58         acpi_status status = AE_OK;
59
60
61         if (!device)
62                 return -EINVAL;
63
64         /* TBD: Support fixed-feature devices */
65
66         status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
67         if (ACPI_FAILURE(status) || !*device) {
68                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
69                                   handle));
70                 return -ENODEV;
71         }
72
73         return 0;
74 }
75
76 EXPORT_SYMBOL(acpi_bus_get_device);
77
78 int acpi_bus_get_status(struct acpi_device *device)
79 {
80         acpi_status status = AE_OK;
81         unsigned long sta = 0;
82
83
84         if (!device)
85                 return -EINVAL;
86
87         /*
88          * Evaluate _STA if present.
89          */
90         if (device->flags.dynamic_status) {
91                 status =
92                     acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
93                 if (ACPI_FAILURE(status))
94                         return -ENODEV;
95                 STRUCT_TO_INT(device->status) = (int)sta;
96         }
97
98         /*
99          * Otherwise we assume the status of our parent (unless we don't
100          * have one, in which case status is implied).
101          */
102         else if (device->parent)
103                 device->status = device->parent->status;
104         else
105                 STRUCT_TO_INT(device->status) =
106                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
107                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
108
109         if (device->status.functional && !device->status.present) {
110                 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
111                        "functional but not present; setting present\n",
112                        device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
113                 device->status.present = 1;
114         }
115
116         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
117                           device->pnp.bus_id,
118                           (u32) STRUCT_TO_INT(device->status)));
119
120         return 0;
121 }
122
123 EXPORT_SYMBOL(acpi_bus_get_status);
124
125 /* --------------------------------------------------------------------------
126                                  Power Management
127    -------------------------------------------------------------------------- */
128
129 int acpi_bus_get_power(acpi_handle handle, int *state)
130 {
131         int result = 0;
132         acpi_status status = 0;
133         struct acpi_device *device = NULL;
134         unsigned long psc = 0;
135
136
137         result = acpi_bus_get_device(handle, &device);
138         if (result)
139                 return result;
140
141         *state = ACPI_STATE_UNKNOWN;
142
143         if (!device->flags.power_manageable) {
144                 /* TBD: Non-recursive algorithm for walking up hierarchy */
145                 if (device->parent)
146                         *state = device->parent->power.state;
147                 else
148                         *state = ACPI_STATE_D0;
149         } else {
150                 /*
151                  * Get the device's power state either directly (via _PSC) or
152                  * indirectly (via power resources).
153                  */
154                 if (device->power.flags.explicit_get) {
155                         status = acpi_evaluate_integer(device->handle, "_PSC",
156                                                        NULL, &psc);
157                         if (ACPI_FAILURE(status))
158                                 return -ENODEV;
159                         device->power.state = (int)psc;
160                 } else if (device->power.flags.power_resources) {
161                         result = acpi_power_get_inferred_state(device);
162                         if (result)
163                                 return result;
164                 }
165
166                 *state = device->power.state;
167         }
168
169         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
170                           device->pnp.bus_id, device->power.state));
171
172         return 0;
173 }
174
175 EXPORT_SYMBOL(acpi_bus_get_power);
176
177 int acpi_bus_set_power(acpi_handle handle, int state)
178 {
179         int result = 0;
180         acpi_status status = AE_OK;
181         struct acpi_device *device = NULL;
182         char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
183
184
185         result = acpi_bus_get_device(handle, &device);
186         if (result)
187                 return result;
188
189         if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
190                 return -EINVAL;
191
192         /* Make sure this is a valid target state */
193
194         if (!device->flags.power_manageable) {
195                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
196                                 kobject_name(&device->dev.kobj)));
197                 return -ENODEV;
198         }
199         /*
200          * Get device's current power state
201          */
202         acpi_bus_get_power(device->handle, &device->power.state);
203         if ((state == device->power.state) && !device->flags.force_power_state) {
204                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
205                                   state));
206                 return 0;
207         }
208
209         if (!device->power.states[state].flags.valid) {
210                 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
211                 return -ENODEV;
212         }
213         if (device->parent && (state < device->parent->power.state)) {
214                 printk(KERN_WARNING PREFIX
215                               "Cannot set device to a higher-powered"
216                               " state than parent\n");
217                 return -ENODEV;
218         }
219
220         /*
221          * Transition Power
222          * ----------------
223          * On transitions to a high-powered state we first apply power (via
224          * power resources) then evalute _PSx.  Conversly for transitions to
225          * a lower-powered state.
226          */
227         if (state < device->power.state) {
228                 if (device->power.flags.power_resources) {
229                         result = acpi_power_transition(device, state);
230                         if (result)
231                                 goto end;
232                 }
233                 if (device->power.states[state].flags.explicit_set) {
234                         status = acpi_evaluate_object(device->handle,
235                                                       object_name, NULL, NULL);
236                         if (ACPI_FAILURE(status)) {
237                                 result = -ENODEV;
238                                 goto end;
239                         }
240                 }
241         } else {
242                 if (device->power.states[state].flags.explicit_set) {
243                         status = acpi_evaluate_object(device->handle,
244                                                       object_name, NULL, NULL);
245                         if (ACPI_FAILURE(status)) {
246                                 result = -ENODEV;
247                                 goto end;
248                         }
249                 }
250                 if (device->power.flags.power_resources) {
251                         result = acpi_power_transition(device, state);
252                         if (result)
253                                 goto end;
254                 }
255         }
256
257       end:
258         if (result)
259                 printk(KERN_WARNING PREFIX
260                               "Transitioning device [%s] to D%d\n",
261                               device->pnp.bus_id, state);
262         else {
263                 device->power.state = state;
264                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
265                                   "Device [%s] transitioned to D%d\n",
266                                   device->pnp.bus_id, state));
267         }
268
269         return result;
270 }
271
272 EXPORT_SYMBOL(acpi_bus_set_power);
273
274 /* --------------------------------------------------------------------------
275                                 Event Management
276    -------------------------------------------------------------------------- */
277
278 #ifdef CONFIG_ACPI_PROC_EVENT
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_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
287 {
288         struct acpi_bus_event *event;
289         unsigned long flags = 0;
290
291         /* drop event on the floor if no one's listening */
292         if (!event_is_open)
293                 return 0;
294
295         event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
296         if (!event)
297                 return -ENOMEM;
298
299         strcpy(event->device_class, device_class);
300         strcpy(event->bus_id, bus_id);
301         event->type = type;
302         event->data = data;
303
304         spin_lock_irqsave(&acpi_bus_event_lock, flags);
305         list_add_tail(&event->node, &acpi_bus_event_list);
306         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
307
308         wake_up_interruptible(&acpi_bus_event_queue);
309
310         return 0;
311
312 }
313
314 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
315
316 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
317 {
318         if (!device)
319                 return -EINVAL;
320         return acpi_bus_generate_proc_event4(device->pnp.device_class,
321                                              device->pnp.bus_id, type, data);
322 }
323
324 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
325
326 int acpi_bus_receive_event(struct acpi_bus_event *event)
327 {
328         unsigned long flags = 0;
329         struct acpi_bus_event *entry = NULL;
330
331         DECLARE_WAITQUEUE(wait, current);
332
333
334         if (!event)
335                 return -EINVAL;
336
337         if (list_empty(&acpi_bus_event_list)) {
338
339                 set_current_state(TASK_INTERRUPTIBLE);
340                 add_wait_queue(&acpi_bus_event_queue, &wait);
341
342                 if (list_empty(&acpi_bus_event_list))
343                         schedule();
344
345                 remove_wait_queue(&acpi_bus_event_queue, &wait);
346                 set_current_state(TASK_RUNNING);
347
348                 if (signal_pending(current))
349                         return -ERESTARTSYS;
350         }
351
352         spin_lock_irqsave(&acpi_bus_event_lock, flags);
353         entry =
354             list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
355         if (entry)
356                 list_del(&entry->node);
357         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
358
359         if (!entry)
360                 return -ENODEV;
361
362         memcpy(event, entry, sizeof(struct acpi_bus_event));
363
364         kfree(entry);
365
366         return 0;
367 }
368
369 EXPORT_SYMBOL(acpi_bus_receive_event);
370 #endif  /* CONFIG_ACPI_PROC_EVENT */
371
372 /* --------------------------------------------------------------------------
373                              Notification Handling
374    -------------------------------------------------------------------------- */
375
376 static int
377 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
378 {
379         acpi_status status = 0;
380         struct acpi_device_status old_status;
381
382
383         if (!device)
384                 return -EINVAL;
385
386         if (status_changed)
387                 *status_changed = 0;
388
389         old_status = device->status;
390
391         /*
392          * Make sure this device's parent is present before we go about
393          * messing with the device.
394          */
395         if (device->parent && !device->parent->status.present) {
396                 device->status = device->parent->status;
397                 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
398                         if (status_changed)
399                                 *status_changed = 1;
400                 }
401                 return 0;
402         }
403
404         status = acpi_bus_get_status(device);
405         if (ACPI_FAILURE(status))
406                 return -ENODEV;
407
408         if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
409                 return 0;
410
411         if (status_changed)
412                 *status_changed = 1;
413
414         /*
415          * Device Insertion/Removal
416          */
417         if ((device->status.present) && !(old_status.present)) {
418                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
419                 /* TBD: Handle device insertion */
420         } else if (!(device->status.present) && (old_status.present)) {
421                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
422                 /* TBD: Handle device removal */
423         }
424
425         return 0;
426 }
427
428 static int acpi_bus_check_scope(struct acpi_device *device)
429 {
430         int result = 0;
431         int status_changed = 0;
432
433
434         if (!device)
435                 return -EINVAL;
436
437         /* Status Change? */
438         result = acpi_bus_check_device(device, &status_changed);
439         if (result)
440                 return result;
441
442         if (!status_changed)
443                 return 0;
444
445         /*
446          * TBD: Enumerate child devices within this device's scope and
447          *       run acpi_bus_check_device()'s on them.
448          */
449
450         return 0;
451 }
452
453 /**
454  * acpi_bus_notify
455  * ---------------
456  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
457  */
458 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
459 {
460         int result = 0;
461         struct acpi_device *device = NULL;
462
463
464         if (acpi_bus_get_device(handle, &device))
465                 return;
466
467         switch (type) {
468
469         case ACPI_NOTIFY_BUS_CHECK:
470                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
471                                   "Received BUS CHECK notification for device [%s]\n",
472                                   device->pnp.bus_id));
473                 result = acpi_bus_check_scope(device);
474                 /*
475                  * TBD: We'll need to outsource certain events to non-ACPI
476                  *      drivers via the device manager (device.c).
477                  */
478                 break;
479
480         case ACPI_NOTIFY_DEVICE_CHECK:
481                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
482                                   "Received DEVICE CHECK notification for device [%s]\n",
483                                   device->pnp.bus_id));
484                 result = acpi_bus_check_device(device, NULL);
485                 /*
486                  * TBD: We'll need to outsource certain events to non-ACPI
487                  *      drivers via the device manager (device.c).
488                  */
489                 break;
490
491         case ACPI_NOTIFY_DEVICE_WAKE:
492                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
493                                   "Received DEVICE WAKE notification for device [%s]\n",
494                                   device->pnp.bus_id));
495                 /* TBD */
496                 break;
497
498         case ACPI_NOTIFY_EJECT_REQUEST:
499                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
500                                   "Received EJECT REQUEST notification for device [%s]\n",
501                                   device->pnp.bus_id));
502                 /* TBD */
503                 break;
504
505         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
506                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
507                                   "Received DEVICE CHECK LIGHT notification for device [%s]\n",
508                                   device->pnp.bus_id));
509                 /* TBD: Exactly what does 'light' mean? */
510                 break;
511
512         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
513                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
514                                   "Received FREQUENCY MISMATCH notification for device [%s]\n",
515                                   device->pnp.bus_id));
516                 /* TBD */
517                 break;
518
519         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
520                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
521                                   "Received BUS MODE MISMATCH notification for device [%s]\n",
522                                   device->pnp.bus_id));
523                 /* TBD */
524                 break;
525
526         case ACPI_NOTIFY_POWER_FAULT:
527                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
528                                   "Received POWER FAULT notification for device [%s]\n",
529                                   device->pnp.bus_id));
530                 /* TBD */
531                 break;
532
533         default:
534                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
535                                   "Received unknown/unsupported notification [%08x]\n",
536                                   type));
537                 break;
538         }
539
540         return;
541 }
542
543 /* --------------------------------------------------------------------------
544                              Initialization/Cleanup
545    -------------------------------------------------------------------------- */
546
547 static int __init acpi_bus_init_irq(void)
548 {
549         acpi_status status = AE_OK;
550         union acpi_object arg = { ACPI_TYPE_INTEGER };
551         struct acpi_object_list arg_list = { 1, &arg };
552         char *message = NULL;
553
554
555         /*
556          * Let the system know what interrupt model we are using by
557          * evaluating the \_PIC object, if exists.
558          */
559
560         switch (acpi_irq_model) {
561         case ACPI_IRQ_MODEL_PIC:
562                 message = "PIC";
563                 break;
564         case ACPI_IRQ_MODEL_IOAPIC:
565                 message = "IOAPIC";
566                 break;
567         case ACPI_IRQ_MODEL_IOSAPIC:
568                 message = "IOSAPIC";
569                 break;
570         case ACPI_IRQ_MODEL_PLATFORM:
571                 message = "platform specific model";
572                 break;
573         default:
574                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
575                 return -ENODEV;
576         }
577
578         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
579
580         arg.integer.value = acpi_irq_model;
581
582         status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
583         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
584                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
585                 return -ENODEV;
586         }
587
588         return 0;
589 }
590
591 acpi_native_uint acpi_gbl_permanent_mmap;
592
593
594 void __init acpi_early_init(void)
595 {
596         acpi_status status = AE_OK;
597
598         if (acpi_disabled)
599                 return;
600
601         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
602
603         /* enable workarounds, unless strict ACPI spec. compliance */
604         if (!acpi_strict)
605                 acpi_gbl_enable_interpreter_slack = TRUE;
606
607         acpi_gbl_permanent_mmap = 1;
608
609         status = acpi_reallocate_root_table();
610         if (ACPI_FAILURE(status)) {
611                 printk(KERN_ERR PREFIX
612                        "Unable to reallocate ACPI tables\n");
613                 goto error0;
614         }
615
616         status = acpi_initialize_subsystem();
617         if (ACPI_FAILURE(status)) {
618                 printk(KERN_ERR PREFIX
619                        "Unable to initialize the ACPI Interpreter\n");
620                 goto error0;
621         }
622
623         status = acpi_load_tables();
624         if (ACPI_FAILURE(status)) {
625                 printk(KERN_ERR PREFIX
626                        "Unable to load the System Description Tables\n");
627                 goto error0;
628         }
629
630 #ifdef CONFIG_X86
631         if (!acpi_ioapic) {
632                 extern u8 acpi_sci_flags;
633
634                 /* compatible (0) means level (3) */
635                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
636                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
637                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
638                 }
639                 /* Set PIC-mode SCI trigger type */
640                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
641                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
642         } else {
643                 extern int acpi_sci_override_gsi;
644                 /*
645                  * now that acpi_gbl_FADT is initialized,
646                  * update it with result from INT_SRC_OVR parsing
647                  */
648                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
649         }
650 #endif
651
652         status =
653             acpi_enable_subsystem(~
654                                   (ACPI_NO_HARDWARE_INIT |
655                                    ACPI_NO_ACPI_ENABLE));
656         if (ACPI_FAILURE(status)) {
657                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
658                 goto error0;
659         }
660
661         return;
662
663       error0:
664         disable_acpi();
665         return;
666 }
667
668 static int __init acpi_bus_init(void)
669 {
670         int result = 0;
671         acpi_status status = AE_OK;
672         extern acpi_status acpi_os_initialize1(void);
673
674
675         status = acpi_os_initialize1();
676
677         status =
678             acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
679         if (ACPI_FAILURE(status)) {
680                 printk(KERN_ERR PREFIX
681                        "Unable to start the ACPI Interpreter\n");
682                 goto error1;
683         }
684
685         if (ACPI_FAILURE(status)) {
686                 printk(KERN_ERR PREFIX
687                        "Unable to initialize ACPI OS objects\n");
688                 goto error1;
689         }
690 #ifdef CONFIG_ACPI_EC
691         /*
692          * ACPI 2.0 requires the EC driver to be loaded and work before
693          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
694          * is called).
695          *
696          * This is accomplished by looking for the ECDT table, and getting
697          * the EC parameters out of that.
698          */
699         status = acpi_ec_ecdt_probe();
700         /* Ignore result. Not having an ECDT is not fatal. */
701 #endif
702
703         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
704         if (ACPI_FAILURE(status)) {
705                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
706                 goto error1;
707         }
708
709         printk(KERN_INFO PREFIX "Interpreter enabled\n");
710
711         /* Initialize sleep structures */
712         acpi_sleep_init();
713
714         /*
715          * Get the system interrupt model and evaluate \_PIC.
716          */
717         result = acpi_bus_init_irq();
718         if (result)
719                 goto error1;
720
721         /*
722          * Register the for all standard device notifications.
723          */
724         status =
725             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
726                                         &acpi_bus_notify, NULL);
727         if (ACPI_FAILURE(status)) {
728                 printk(KERN_ERR PREFIX
729                        "Unable to register for device notifications\n");
730                 goto error1;
731         }
732
733         /*
734          * Create the top ACPI proc directory
735          */
736         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
737
738         return 0;
739
740         /* Mimic structured exception handling */
741       error1:
742         acpi_terminate();
743         return -ENODEV;
744 }
745
746 decl_subsys(acpi, NULL, NULL);
747
748 static int __init acpi_init(void)
749 {
750         int result = 0;
751
752
753         if (acpi_disabled) {
754                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
755                 return -ENODEV;
756         }
757
758         result = firmware_register(&acpi_subsys);
759         if (result < 0)
760                 printk(KERN_WARNING "%s: firmware_register error: %d\n",
761                         __FUNCTION__, result);
762
763         result = acpi_bus_init();
764
765         if (!result) {
766                 if (!(pm_flags & PM_APM))
767                         pm_flags |= PM_ACPI;
768                 else {
769                         printk(KERN_INFO PREFIX
770                                "APM is already active, exiting\n");
771                         disable_acpi();
772                         result = -ENODEV;
773                 }
774         } else
775                 disable_acpi();
776
777         return result;
778 }
779
780 subsys_initcall(acpi_init);