bus.c revision 19c38de88a80913351fcacefdb461cc0b585fa87 
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
42ACPI_MODULE_NAME("bus");
43#ifdef	CONFIG_X86
44extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
45#endif
46
47struct acpi_device *acpi_root;
48struct proc_dir_entry *acpi_root_dir;
49EXPORT_SYMBOL(acpi_root_dir);
50
51#define STRUCT_TO_INT(s)	(*((int*)&s))
52
53/* --------------------------------------------------------------------------
54                                Device Management
55   -------------------------------------------------------------------------- */
56
57int 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
77EXPORT_SYMBOL(acpi_bus_get_device);
78
79int 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
124EXPORT_SYMBOL(acpi_bus_get_status);
125
126/* --------------------------------------------------------------------------
127                                 Power Management
128   -------------------------------------------------------------------------- */
129
130int 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
176EXPORT_SYMBOL(acpi_bus_get_power);
177
178int 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 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		device->power.state = state;
267		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
268				  "Device [%s] transitioned to D%d\n",
269				  device->pnp.bus_id, state));
270	}
271
272	return result;
273}
274
275EXPORT_SYMBOL(acpi_bus_set_power);
276
277/* --------------------------------------------------------------------------
278                                Event Management
279   -------------------------------------------------------------------------- */
280
281#ifdef CONFIG_ACPI_PROC_EVENT
282static DEFINE_SPINLOCK(acpi_bus_event_lock);
283
284LIST_HEAD(acpi_bus_event_list);
285DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
286
287extern int event_is_open;
288
289int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
290{
291	struct acpi_bus_event *event = NULL;
292	unsigned long flags = 0;
293
294
295	if (!device)
296		return -EINVAL;
297
298	/* drop event on the floor if no one's listening */
299	if (!event_is_open)
300		return 0;
301
302	event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
303	if (!event)
304		return -ENOMEM;
305
306	strcpy(event->device_class, device->pnp.device_class);
307	strcpy(event->bus_id, device->pnp.bus_id);
308	event->type = type;
309	event->data = data;
310
311	spin_lock_irqsave(&acpi_bus_event_lock, flags);
312	list_add_tail(&event->node, &acpi_bus_event_list);
313	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
314
315	wake_up_interruptible(&acpi_bus_event_queue);
316
317	return 0;
318}
319
320EXPORT_SYMBOL(acpi_bus_generate_proc_event);
321
322int acpi_bus_receive_event(struct acpi_bus_event *event)
323{
324	unsigned long flags = 0;
325	struct acpi_bus_event *entry = NULL;
326
327	DECLARE_WAITQUEUE(wait, current);
328
329
330	if (!event)
331		return -EINVAL;
332
333	if (list_empty(&acpi_bus_event_list)) {
334
335		set_current_state(TASK_INTERRUPTIBLE);
336		add_wait_queue(&acpi_bus_event_queue, &wait);
337
338		if (list_empty(&acpi_bus_event_list))
339			schedule();
340
341		remove_wait_queue(&acpi_bus_event_queue, &wait);
342		set_current_state(TASK_RUNNING);
343
344		if (signal_pending(current))
345			return -ERESTARTSYS;
346	}
347
348	spin_lock_irqsave(&acpi_bus_event_lock, flags);
349	entry =
350	    list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
351	if (entry)
352		list_del(&entry->node);
353	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
354
355	if (!entry)
356		return -ENODEV;
357
358	memcpy(event, entry, sizeof(struct acpi_bus_event));
359
360	kfree(entry);
361
362	return 0;
363}
364
365EXPORT_SYMBOL(acpi_bus_receive_event);
366#endif	/* CONFIG_ACPI_PROC_EVENT */
367
368/* --------------------------------------------------------------------------
369                             Notification Handling
370   -------------------------------------------------------------------------- */
371
372static int
373acpi_bus_check_device(struct acpi_device *device, int *status_changed)
374{
375	acpi_status status = 0;
376	struct acpi_device_status old_status;
377
378
379	if (!device)
380		return -EINVAL;
381
382	if (status_changed)
383		*status_changed = 0;
384
385	old_status = device->status;
386
387	/*
388	 * Make sure this device's parent is present before we go about
389	 * messing with the device.
390	 */
391	if (device->parent && !device->parent->status.present) {
392		device->status = device->parent->status;
393		if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
394			if (status_changed)
395				*status_changed = 1;
396		}
397		return 0;
398	}
399
400	status = acpi_bus_get_status(device);
401	if (ACPI_FAILURE(status))
402		return -ENODEV;
403
404	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
405		return 0;
406
407	if (status_changed)
408		*status_changed = 1;
409
410	/*
411	 * Device Insertion/Removal
412	 */
413	if ((device->status.present) && !(old_status.present)) {
414		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
415		/* TBD: Handle device insertion */
416	} else if (!(device->status.present) && (old_status.present)) {
417		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
418		/* TBD: Handle device removal */
419	}
420
421	return 0;
422}
423
424static int acpi_bus_check_scope(struct acpi_device *device)
425{
426	int result = 0;
427	int status_changed = 0;
428
429
430	if (!device)
431		return -EINVAL;
432
433	/* Status Change? */
434	result = acpi_bus_check_device(device, &status_changed);
435	if (result)
436		return result;
437
438	if (!status_changed)
439		return 0;
440
441	/*
442	 * TBD: Enumerate child devices within this device's scope and
443	 *       run acpi_bus_check_device()'s on them.
444	 */
445
446	return 0;
447}
448
449/**
450 * acpi_bus_notify
451 * ---------------
452 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
453 */
454static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
455{
456	int result = 0;
457	struct acpi_device *device = NULL;
458
459
460	if (acpi_bus_get_device(handle, &device))
461		return;
462
463	switch (type) {
464
465	case ACPI_NOTIFY_BUS_CHECK:
466		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
467				  "Received BUS CHECK notification for device [%s]\n",
468				  device->pnp.bus_id));
469		result = acpi_bus_check_scope(device);
470		/*
471		 * TBD: We'll need to outsource certain events to non-ACPI
472		 *      drivers via the device manager (device.c).
473		 */
474		break;
475
476	case ACPI_NOTIFY_DEVICE_CHECK:
477		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
478				  "Received DEVICE CHECK notification for device [%s]\n",
479				  device->pnp.bus_id));
480		result = acpi_bus_check_device(device, NULL);
481		/*
482		 * TBD: We'll need to outsource certain events to non-ACPI
483		 *      drivers via the device manager (device.c).
484		 */
485		break;
486
487	case ACPI_NOTIFY_DEVICE_WAKE:
488		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
489				  "Received DEVICE WAKE notification for device [%s]\n",
490				  device->pnp.bus_id));
491		/* TBD */
492		break;
493
494	case ACPI_NOTIFY_EJECT_REQUEST:
495		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
496				  "Received EJECT REQUEST notification for device [%s]\n",
497				  device->pnp.bus_id));
498		/* TBD */
499		break;
500
501	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
502		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
503				  "Received DEVICE CHECK LIGHT notification for device [%s]\n",
504				  device->pnp.bus_id));
505		/* TBD: Exactly what does 'light' mean? */
506		break;
507
508	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
509		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
510				  "Received FREQUENCY MISMATCH notification for device [%s]\n",
511				  device->pnp.bus_id));
512		/* TBD */
513		break;
514
515	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
516		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
517				  "Received BUS MODE MISMATCH notification for device [%s]\n",
518				  device->pnp.bus_id));
519		/* TBD */
520		break;
521
522	case ACPI_NOTIFY_POWER_FAULT:
523		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
524				  "Received POWER FAULT notification for device [%s]\n",
525				  device->pnp.bus_id));
526		/* TBD */
527		break;
528
529	default:
530		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
531				  "Received unknown/unsupported notification [%08x]\n",
532				  type));
533		break;
534	}
535
536	return;
537}
538
539/* --------------------------------------------------------------------------
540                             Initialization/Cleanup
541   -------------------------------------------------------------------------- */
542
543static int __init acpi_bus_init_irq(void)
544{
545	acpi_status status = AE_OK;
546	union acpi_object arg = { ACPI_TYPE_INTEGER };
547	struct acpi_object_list arg_list = { 1, &arg };
548	char *message = NULL;
549
550
551	/*
552	 * Let the system know what interrupt model we are using by
553	 * evaluating the \_PIC object, if exists.
554	 */
555
556	switch (acpi_irq_model) {
557	case ACPI_IRQ_MODEL_PIC:
558		message = "PIC";
559		break;
560	case ACPI_IRQ_MODEL_IOAPIC:
561		message = "IOAPIC";
562		break;
563	case ACPI_IRQ_MODEL_IOSAPIC:
564		message = "IOSAPIC";
565		break;
566	case ACPI_IRQ_MODEL_PLATFORM:
567		message = "platform specific model";
568		break;
569	default:
570		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
571		return -ENODEV;
572	}
573
574	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
575
576	arg.integer.value = acpi_irq_model;
577
578	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
579	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
580		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
581		return -ENODEV;
582	}
583
584	return 0;
585}
586
587acpi_native_uint acpi_gbl_permanent_mmap;
588
589
590void __init acpi_early_init(void)
591{
592	acpi_status status = AE_OK;
593
594	if (acpi_disabled)
595		return;
596
597	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
598
599	/* enable workarounds, unless strict ACPI spec. compliance */
600	if (!acpi_strict)
601		acpi_gbl_enable_interpreter_slack = TRUE;
602
603	acpi_gbl_permanent_mmap = 1;
604
605	status = acpi_reallocate_root_table();
606	if (ACPI_FAILURE(status)) {
607		printk(KERN_ERR PREFIX
608		       "Unable to reallocate ACPI tables\n");
609		goto error0;
610	}
611
612	status = acpi_initialize_subsystem();
613	if (ACPI_FAILURE(status)) {
614		printk(KERN_ERR PREFIX
615		       "Unable to initialize the ACPI Interpreter\n");
616		goto error0;
617	}
618
619	status = acpi_load_tables();
620	if (ACPI_FAILURE(status)) {
621		printk(KERN_ERR PREFIX
622		       "Unable to load the System Description Tables\n");
623		goto error0;
624	}
625
626#ifdef CONFIG_X86
627	if (!acpi_ioapic) {
628		extern u8 acpi_sci_flags;
629
630		/* compatible (0) means level (3) */
631		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
632			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
633			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
634		}
635		/* Set PIC-mode SCI trigger type */
636		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
637					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
638	} else {
639		extern int acpi_sci_override_gsi;
640		/*
641		 * now that acpi_gbl_FADT is initialized,
642		 * update it with result from INT_SRC_OVR parsing
643		 */
644		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
645	}
646#endif
647
648	status =
649	    acpi_enable_subsystem(~
650				  (ACPI_NO_HARDWARE_INIT |
651				   ACPI_NO_ACPI_ENABLE));
652	if (ACPI_FAILURE(status)) {
653		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
654		goto error0;
655	}
656
657	return;
658
659      error0:
660	disable_acpi();
661	return;
662}
663
664static int __init acpi_bus_init(void)
665{
666	int result = 0;
667	acpi_status status = AE_OK;
668	extern acpi_status acpi_os_initialize1(void);
669
670
671	status = acpi_os_initialize1();
672
673	status =
674	    acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
675	if (ACPI_FAILURE(status)) {
676		printk(KERN_ERR PREFIX
677		       "Unable to start the ACPI Interpreter\n");
678		goto error1;
679	}
680
681	if (ACPI_FAILURE(status)) {
682		printk(KERN_ERR PREFIX
683		       "Unable to initialize ACPI OS objects\n");
684		goto error1;
685	}
686#ifdef CONFIG_ACPI_EC
687	/*
688	 * ACPI 2.0 requires the EC driver to be loaded and work before
689	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
690	 * is called).
691	 *
692	 * This is accomplished by looking for the ECDT table, and getting
693	 * the EC parameters out of that.
694	 */
695	status = acpi_ec_ecdt_probe();
696	/* Ignore result. Not having an ECDT is not fatal. */
697#endif
698
699	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
700	if (ACPI_FAILURE(status)) {
701		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
702		goto error1;
703	}
704
705	printk(KERN_INFO PREFIX "Interpreter enabled\n");
706
707	/* Initialize sleep structures */
708	acpi_sleep_init();
709
710	/*
711	 * Get the system interrupt model and evaluate \_PIC.
712	 */
713	result = acpi_bus_init_irq();
714	if (result)
715		goto error1;
716
717	/*
718	 * Register the for all standard device notifications.
719	 */
720	status =
721	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
722					&acpi_bus_notify, NULL);
723	if (ACPI_FAILURE(status)) {
724		printk(KERN_ERR PREFIX
725		       "Unable to register for device notifications\n");
726		goto error1;
727	}
728
729	/*
730	 * Create the top ACPI proc directory
731	 */
732	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
733
734	return 0;
735
736	/* Mimic structured exception handling */
737      error1:
738	acpi_terminate();
739	return -ENODEV;
740}
741
742decl_subsys(acpi, NULL, NULL);
743
744static int __init acpi_init(void)
745{
746	int result = 0;
747
748
749	if (acpi_disabled) {
750		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
751		return -ENODEV;
752	}
753
754	result = firmware_register(&acpi_subsys);
755	if (result < 0)
756		printk(KERN_WARNING "%s: firmware_register error: %d\n",
757			__FUNCTION__, result);
758
759	result = acpi_bus_init();
760
761	if (!result) {
762#ifdef CONFIG_PM_LEGACY
763		if (!PM_IS_ACTIVE())
764			pm_active = 1;
765		else {
766			printk(KERN_INFO PREFIX
767			       "APM is already active, exiting\n");
768			disable_acpi();
769			result = -ENODEV;
770		}
771#endif
772	} else
773		disable_acpi();
774
775	return result;
776}
777
778subsys_initcall(acpi_init);
779