xref: /openbmc/linux/drivers/acpi/bus.c (revision f15cbe6f1a4b4d9df59142fc8e4abb973302cf44)
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 #include <linux/acpi.h>
35 #ifdef CONFIG_X86
36 #include <asm/mpspec.h>
37 #endif
38 #include <linux/pci.h>
39 #include <acpi/acpi_bus.h>
40 #include <acpi/acpi_drivers.h>
41 
42 #define _COMPONENT		ACPI_BUS_COMPONENT
43 ACPI_MODULE_NAME("bus");
44 
45 struct acpi_device *acpi_root;
46 struct proc_dir_entry *acpi_root_dir;
47 EXPORT_SYMBOL(acpi_root_dir);
48 
49 #define STRUCT_TO_INT(s)	(*((int*)&s))
50 
51 /* --------------------------------------------------------------------------
52                                 Device Management
53    -------------------------------------------------------------------------- */
54 
55 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
56 {
57 	acpi_status status = AE_OK;
58 
59 
60 	if (!device)
61 		return -EINVAL;
62 
63 	/* TBD: Support fixed-feature devices */
64 
65 	status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
66 	if (ACPI_FAILURE(status) || !*device) {
67 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
68 				  handle));
69 		return -ENODEV;
70 	}
71 
72 	return 0;
73 }
74 
75 EXPORT_SYMBOL(acpi_bus_get_device);
76 
77 int acpi_bus_get_status(struct acpi_device *device)
78 {
79 	acpi_status status = AE_OK;
80 	unsigned long sta = 0;
81 
82 
83 	if (!device)
84 		return -EINVAL;
85 
86 	/*
87 	 * Evaluate _STA if present.
88 	 */
89 	if (device->flags.dynamic_status) {
90 		status =
91 		    acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
92 		if (ACPI_FAILURE(status))
93 			return -ENODEV;
94 		STRUCT_TO_INT(device->status) = (int)sta;
95 	}
96 
97 	/*
98 	 * Otherwise we assume the status of our parent (unless we don't
99 	 * have one, in which case status is implied).
100 	 */
101 	else if (device->parent)
102 		device->status = device->parent->status;
103 	else
104 		STRUCT_TO_INT(device->status) =
105 		    ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
106 		    ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
107 
108 	if (device->status.functional && !device->status.present) {
109 		printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
110 		       "functional but not present; setting present\n",
111 		       device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
112 		device->status.present = 1;
113 	}
114 
115 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
116 			  device->pnp.bus_id,
117 			  (u32) STRUCT_TO_INT(device->status)));
118 
119 	return 0;
120 }
121 
122 EXPORT_SYMBOL(acpi_bus_get_status);
123 
124 void acpi_bus_private_data_handler(acpi_handle handle,
125 				   u32 function, void *context)
126 {
127 	return;
128 }
129 EXPORT_SYMBOL(acpi_bus_private_data_handler);
130 
131 int acpi_bus_get_private_data(acpi_handle handle, void **data)
132 {
133 	acpi_status status = AE_OK;
134 
135 	if (!*data)
136 		return -EINVAL;
137 
138 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
139 	if (ACPI_FAILURE(status) || !*data) {
140 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
141 				handle));
142 		return -ENODEV;
143 	}
144 
145 	return 0;
146 }
147 EXPORT_SYMBOL(acpi_bus_get_private_data);
148 
149 /* --------------------------------------------------------------------------
150                                  Power Management
151    -------------------------------------------------------------------------- */
152 
153 int acpi_bus_get_power(acpi_handle handle, int *state)
154 {
155 	int result = 0;
156 	acpi_status status = 0;
157 	struct acpi_device *device = NULL;
158 	unsigned long psc = 0;
159 
160 
161 	result = acpi_bus_get_device(handle, &device);
162 	if (result)
163 		return result;
164 
165 	*state = ACPI_STATE_UNKNOWN;
166 
167 	if (!device->flags.power_manageable) {
168 		/* TBD: Non-recursive algorithm for walking up hierarchy */
169 		if (device->parent)
170 			*state = device->parent->power.state;
171 		else
172 			*state = ACPI_STATE_D0;
173 	} else {
174 		/*
175 		 * Get the device's power state either directly (via _PSC) or
176 		 * indirectly (via power resources).
177 		 */
178 		if (device->power.flags.explicit_get) {
179 			status = acpi_evaluate_integer(device->handle, "_PSC",
180 						       NULL, &psc);
181 			if (ACPI_FAILURE(status))
182 				return -ENODEV;
183 			device->power.state = (int)psc;
184 		} else if (device->power.flags.power_resources) {
185 			result = acpi_power_get_inferred_state(device);
186 			if (result)
187 				return result;
188 		}
189 
190 		*state = device->power.state;
191 	}
192 
193 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
194 			  device->pnp.bus_id, device->power.state));
195 
196 	return 0;
197 }
198 
199 EXPORT_SYMBOL(acpi_bus_get_power);
200 
201 int acpi_bus_set_power(acpi_handle handle, int state)
202 {
203 	int result = 0;
204 	acpi_status status = AE_OK;
205 	struct acpi_device *device = NULL;
206 	char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
207 
208 
209 	result = acpi_bus_get_device(handle, &device);
210 	if (result)
211 		return result;
212 
213 	if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
214 		return -EINVAL;
215 
216 	/* Make sure this is a valid target state */
217 
218 	if (!device->flags.power_manageable) {
219 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
220 				kobject_name(&device->dev.kobj)));
221 		return -ENODEV;
222 	}
223 	/*
224 	 * Get device's current power state
225 	 */
226 	acpi_bus_get_power(device->handle, &device->power.state);
227 	if ((state == device->power.state) && !device->flags.force_power_state) {
228 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
229 				  state));
230 		return 0;
231 	}
232 
233 	if (!device->power.states[state].flags.valid) {
234 		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
235 		return -ENODEV;
236 	}
237 	if (device->parent && (state < device->parent->power.state)) {
238 		printk(KERN_WARNING PREFIX
239 			      "Cannot set device to a higher-powered"
240 			      " state than parent\n");
241 		return -ENODEV;
242 	}
243 
244 	/*
245 	 * Transition Power
246 	 * ----------------
247 	 * On transitions to a high-powered state we first apply power (via
248 	 * power resources) then evalute _PSx.  Conversly for transitions to
249 	 * a lower-powered state.
250 	 */
251 	if (state < device->power.state) {
252 		if (device->power.flags.power_resources) {
253 			result = acpi_power_transition(device, state);
254 			if (result)
255 				goto end;
256 		}
257 		if (device->power.states[state].flags.explicit_set) {
258 			status = acpi_evaluate_object(device->handle,
259 						      object_name, NULL, NULL);
260 			if (ACPI_FAILURE(status)) {
261 				result = -ENODEV;
262 				goto end;
263 			}
264 		}
265 	} else {
266 		if (device->power.states[state].flags.explicit_set) {
267 			status = acpi_evaluate_object(device->handle,
268 						      object_name, NULL, NULL);
269 			if (ACPI_FAILURE(status)) {
270 				result = -ENODEV;
271 				goto end;
272 			}
273 		}
274 		if (device->power.flags.power_resources) {
275 			result = acpi_power_transition(device, state);
276 			if (result)
277 				goto end;
278 		}
279 	}
280 
281       end:
282 	if (result)
283 		printk(KERN_WARNING PREFIX
284 			      "Transitioning device [%s] to D%d\n",
285 			      device->pnp.bus_id, state);
286 	else {
287 		device->power.state = state;
288 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
289 				  "Device [%s] transitioned to D%d\n",
290 				  device->pnp.bus_id, state));
291 	}
292 
293 	return result;
294 }
295 
296 EXPORT_SYMBOL(acpi_bus_set_power);
297 
298 bool acpi_bus_power_manageable(acpi_handle handle)
299 {
300 	struct acpi_device *device;
301 	int result;
302 
303 	result = acpi_bus_get_device(handle, &device);
304 	return result ? false : device->flags.power_manageable;
305 }
306 
307 EXPORT_SYMBOL(acpi_bus_power_manageable);
308 
309 bool acpi_bus_can_wakeup(acpi_handle handle)
310 {
311 	struct acpi_device *device;
312 	int result;
313 
314 	result = acpi_bus_get_device(handle, &device);
315 	return result ? false : device->wakeup.flags.valid;
316 }
317 
318 EXPORT_SYMBOL(acpi_bus_can_wakeup);
319 
320 /* --------------------------------------------------------------------------
321                                 Event Management
322    -------------------------------------------------------------------------- */
323 
324 #ifdef CONFIG_ACPI_PROC_EVENT
325 static DEFINE_SPINLOCK(acpi_bus_event_lock);
326 
327 LIST_HEAD(acpi_bus_event_list);
328 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
329 
330 extern int event_is_open;
331 
332 int acpi_bus_generate_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
333 {
334 	struct acpi_bus_event *event;
335 	unsigned long flags = 0;
336 
337 	/* drop event on the floor if no one's listening */
338 	if (!event_is_open)
339 		return 0;
340 
341 	event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
342 	if (!event)
343 		return -ENOMEM;
344 
345 	strcpy(event->device_class, device_class);
346 	strcpy(event->bus_id, bus_id);
347 	event->type = type;
348 	event->data = data;
349 
350 	spin_lock_irqsave(&acpi_bus_event_lock, flags);
351 	list_add_tail(&event->node, &acpi_bus_event_list);
352 	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
353 
354 	wake_up_interruptible(&acpi_bus_event_queue);
355 
356 	return 0;
357 
358 }
359 
360 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
361 
362 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
363 {
364 	if (!device)
365 		return -EINVAL;
366 	return acpi_bus_generate_proc_event4(device->pnp.device_class,
367 					     device->pnp.bus_id, type, data);
368 }
369 
370 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
371 
372 int acpi_bus_receive_event(struct acpi_bus_event *event)
373 {
374 	unsigned long flags = 0;
375 	struct acpi_bus_event *entry = NULL;
376 
377 	DECLARE_WAITQUEUE(wait, current);
378 
379 
380 	if (!event)
381 		return -EINVAL;
382 
383 	if (list_empty(&acpi_bus_event_list)) {
384 
385 		set_current_state(TASK_INTERRUPTIBLE);
386 		add_wait_queue(&acpi_bus_event_queue, &wait);
387 
388 		if (list_empty(&acpi_bus_event_list))
389 			schedule();
390 
391 		remove_wait_queue(&acpi_bus_event_queue, &wait);
392 		set_current_state(TASK_RUNNING);
393 
394 		if (signal_pending(current))
395 			return -ERESTARTSYS;
396 	}
397 
398 	spin_lock_irqsave(&acpi_bus_event_lock, flags);
399 	if (!list_empty(&acpi_bus_event_list)) {
400 		entry = list_entry(acpi_bus_event_list.next,
401 				   struct acpi_bus_event, node);
402 		list_del(&entry->node);
403 	}
404 	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
405 
406 	if (!entry)
407 		return -ENODEV;
408 
409 	memcpy(event, entry, sizeof(struct acpi_bus_event));
410 
411 	kfree(entry);
412 
413 	return 0;
414 }
415 
416 #endif	/* CONFIG_ACPI_PROC_EVENT */
417 
418 /* --------------------------------------------------------------------------
419                              Notification Handling
420    -------------------------------------------------------------------------- */
421 
422 static int
423 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
424 {
425 	acpi_status status = 0;
426 	struct acpi_device_status old_status;
427 
428 
429 	if (!device)
430 		return -EINVAL;
431 
432 	if (status_changed)
433 		*status_changed = 0;
434 
435 	old_status = device->status;
436 
437 	/*
438 	 * Make sure this device's parent is present before we go about
439 	 * messing with the device.
440 	 */
441 	if (device->parent && !device->parent->status.present) {
442 		device->status = device->parent->status;
443 		if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
444 			if (status_changed)
445 				*status_changed = 1;
446 		}
447 		return 0;
448 	}
449 
450 	status = acpi_bus_get_status(device);
451 	if (ACPI_FAILURE(status))
452 		return -ENODEV;
453 
454 	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
455 		return 0;
456 
457 	if (status_changed)
458 		*status_changed = 1;
459 
460 	/*
461 	 * Device Insertion/Removal
462 	 */
463 	if ((device->status.present) && !(old_status.present)) {
464 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
465 		/* TBD: Handle device insertion */
466 	} else if (!(device->status.present) && (old_status.present)) {
467 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
468 		/* TBD: Handle device removal */
469 	}
470 
471 	return 0;
472 }
473 
474 static int acpi_bus_check_scope(struct acpi_device *device)
475 {
476 	int result = 0;
477 	int status_changed = 0;
478 
479 
480 	if (!device)
481 		return -EINVAL;
482 
483 	/* Status Change? */
484 	result = acpi_bus_check_device(device, &status_changed);
485 	if (result)
486 		return result;
487 
488 	if (!status_changed)
489 		return 0;
490 
491 	/*
492 	 * TBD: Enumerate child devices within this device's scope and
493 	 *       run acpi_bus_check_device()'s on them.
494 	 */
495 
496 	return 0;
497 }
498 
499 /**
500  * acpi_bus_notify
501  * ---------------
502  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
503  */
504 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
505 {
506 	int result = 0;
507 	struct acpi_device *device = NULL;
508 
509 
510 	if (acpi_bus_get_device(handle, &device))
511 		return;
512 
513 	switch (type) {
514 
515 	case ACPI_NOTIFY_BUS_CHECK:
516 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
517 				  "Received BUS CHECK notification for device [%s]\n",
518 				  device->pnp.bus_id));
519 		result = acpi_bus_check_scope(device);
520 		/*
521 		 * TBD: We'll need to outsource certain events to non-ACPI
522 		 *      drivers via the device manager (device.c).
523 		 */
524 		break;
525 
526 	case ACPI_NOTIFY_DEVICE_CHECK:
527 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
528 				  "Received DEVICE CHECK notification for device [%s]\n",
529 				  device->pnp.bus_id));
530 		result = acpi_bus_check_device(device, NULL);
531 		/*
532 		 * TBD: We'll need to outsource certain events to non-ACPI
533 		 *      drivers via the device manager (device.c).
534 		 */
535 		break;
536 
537 	case ACPI_NOTIFY_DEVICE_WAKE:
538 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
539 				  "Received DEVICE WAKE notification for device [%s]\n",
540 				  device->pnp.bus_id));
541 		/* TBD */
542 		break;
543 
544 	case ACPI_NOTIFY_EJECT_REQUEST:
545 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
546 				  "Received EJECT REQUEST notification for device [%s]\n",
547 				  device->pnp.bus_id));
548 		/* TBD */
549 		break;
550 
551 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
552 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
553 				  "Received DEVICE CHECK LIGHT notification for device [%s]\n",
554 				  device->pnp.bus_id));
555 		/* TBD: Exactly what does 'light' mean? */
556 		break;
557 
558 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
559 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
560 				  "Received FREQUENCY MISMATCH notification for device [%s]\n",
561 				  device->pnp.bus_id));
562 		/* TBD */
563 		break;
564 
565 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
566 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
567 				  "Received BUS MODE MISMATCH notification for device [%s]\n",
568 				  device->pnp.bus_id));
569 		/* TBD */
570 		break;
571 
572 	case ACPI_NOTIFY_POWER_FAULT:
573 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
574 				  "Received POWER FAULT notification for device [%s]\n",
575 				  device->pnp.bus_id));
576 		/* TBD */
577 		break;
578 
579 	default:
580 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
581 				  "Received unknown/unsupported notification [%08x]\n",
582 				  type));
583 		break;
584 	}
585 
586 	return;
587 }
588 
589 /* --------------------------------------------------------------------------
590                              Initialization/Cleanup
591    -------------------------------------------------------------------------- */
592 
593 static int __init acpi_bus_init_irq(void)
594 {
595 	acpi_status status = AE_OK;
596 	union acpi_object arg = { ACPI_TYPE_INTEGER };
597 	struct acpi_object_list arg_list = { 1, &arg };
598 	char *message = NULL;
599 
600 
601 	/*
602 	 * Let the system know what interrupt model we are using by
603 	 * evaluating the \_PIC object, if exists.
604 	 */
605 
606 	switch (acpi_irq_model) {
607 	case ACPI_IRQ_MODEL_PIC:
608 		message = "PIC";
609 		break;
610 	case ACPI_IRQ_MODEL_IOAPIC:
611 		message = "IOAPIC";
612 		break;
613 	case ACPI_IRQ_MODEL_IOSAPIC:
614 		message = "IOSAPIC";
615 		break;
616 	case ACPI_IRQ_MODEL_PLATFORM:
617 		message = "platform specific model";
618 		break;
619 	default:
620 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
621 		return -ENODEV;
622 	}
623 
624 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
625 
626 	arg.integer.value = acpi_irq_model;
627 
628 	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
629 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
630 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
631 		return -ENODEV;
632 	}
633 
634 	return 0;
635 }
636 
637 u8 acpi_gbl_permanent_mmap;
638 
639 
640 void __init acpi_early_init(void)
641 {
642 	acpi_status status = AE_OK;
643 
644 	if (acpi_disabled)
645 		return;
646 
647 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
648 
649 	/* enable workarounds, unless strict ACPI spec. compliance */
650 	if (!acpi_strict)
651 		acpi_gbl_enable_interpreter_slack = TRUE;
652 
653 	acpi_gbl_permanent_mmap = 1;
654 
655 	status = acpi_reallocate_root_table();
656 	if (ACPI_FAILURE(status)) {
657 		printk(KERN_ERR PREFIX
658 		       "Unable to reallocate ACPI tables\n");
659 		goto error0;
660 	}
661 
662 	status = acpi_initialize_subsystem();
663 	if (ACPI_FAILURE(status)) {
664 		printk(KERN_ERR PREFIX
665 		       "Unable to initialize the ACPI Interpreter\n");
666 		goto error0;
667 	}
668 
669 	status = acpi_load_tables();
670 	if (ACPI_FAILURE(status)) {
671 		printk(KERN_ERR PREFIX
672 		       "Unable to load the System Description Tables\n");
673 		goto error0;
674 	}
675 
676 #ifdef CONFIG_X86
677 	if (!acpi_ioapic) {
678 		/* compatible (0) means level (3) */
679 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
680 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
681 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
682 		}
683 		/* Set PIC-mode SCI trigger type */
684 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
685 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
686 	} else {
687 		/*
688 		 * now that acpi_gbl_FADT is initialized,
689 		 * update it with result from INT_SRC_OVR parsing
690 		 */
691 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
692 	}
693 #endif
694 
695 	status =
696 	    acpi_enable_subsystem(~
697 				  (ACPI_NO_HARDWARE_INIT |
698 				   ACPI_NO_ACPI_ENABLE));
699 	if (ACPI_FAILURE(status)) {
700 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
701 		goto error0;
702 	}
703 
704 	return;
705 
706       error0:
707 	disable_acpi();
708 	return;
709 }
710 
711 static int __init acpi_bus_init(void)
712 {
713 	int result = 0;
714 	acpi_status status = AE_OK;
715 	extern acpi_status acpi_os_initialize1(void);
716 
717 
718 	status = acpi_os_initialize1();
719 
720 	status =
721 	    acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
722 	if (ACPI_FAILURE(status)) {
723 		printk(KERN_ERR PREFIX
724 		       "Unable to start the ACPI Interpreter\n");
725 		goto error1;
726 	}
727 
728 	if (ACPI_FAILURE(status)) {
729 		printk(KERN_ERR PREFIX
730 		       "Unable to initialize ACPI OS objects\n");
731 		goto error1;
732 	}
733 #ifdef CONFIG_ACPI_EC
734 	/*
735 	 * ACPI 2.0 requires the EC driver to be loaded and work before
736 	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
737 	 * is called).
738 	 *
739 	 * This is accomplished by looking for the ECDT table, and getting
740 	 * the EC parameters out of that.
741 	 */
742 	status = acpi_ec_ecdt_probe();
743 	/* Ignore result. Not having an ECDT is not fatal. */
744 #endif
745 
746 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
747 	if (ACPI_FAILURE(status)) {
748 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
749 		goto error1;
750 	}
751 
752 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
753 
754 	/* Initialize sleep structures */
755 	acpi_sleep_init();
756 
757 	/*
758 	 * Get the system interrupt model and evaluate \_PIC.
759 	 */
760 	result = acpi_bus_init_irq();
761 	if (result)
762 		goto error1;
763 
764 	/*
765 	 * Register the for all standard device notifications.
766 	 */
767 	status =
768 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
769 					&acpi_bus_notify, NULL);
770 	if (ACPI_FAILURE(status)) {
771 		printk(KERN_ERR PREFIX
772 		       "Unable to register for device notifications\n");
773 		goto error1;
774 	}
775 
776 	/*
777 	 * Create the top ACPI proc directory
778 	 */
779 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
780 
781 	return 0;
782 
783 	/* Mimic structured exception handling */
784       error1:
785 	acpi_terminate();
786 	return -ENODEV;
787 }
788 
789 struct kobject *acpi_kobj;
790 
791 static int __init acpi_init(void)
792 {
793 	int result = 0;
794 
795 
796 	if (acpi_disabled) {
797 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
798 		return -ENODEV;
799 	}
800 
801 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
802 	if (!acpi_kobj) {
803 		printk(KERN_WARNING "%s: kset create error\n", __func__);
804 		acpi_kobj = NULL;
805 	}
806 
807 	result = acpi_bus_init();
808 
809 	if (!result) {
810 		pci_mmcfg_late_init();
811 		if (!(pm_flags & PM_APM))
812 			pm_flags |= PM_ACPI;
813 		else {
814 			printk(KERN_INFO PREFIX
815 			       "APM is already active, exiting\n");
816 			disable_acpi();
817 			result = -ENODEV;
818 		}
819 	} else
820 		disable_acpi();
821 
822 	return result;
823 }
824 
825 subsys_initcall(acpi_init);
826