ACPI: remove unused "status_changed" return value from Check Device handling
[linux-2.6/linux-2.6-openrd.git] / drivers / acpi / bus.c
blob19e78fb0a8d1be477593d40f927425f572c5a9e8
1 /*
2 * acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
4 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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>
42 #include "internal.h"
44 #define _COMPONENT ACPI_BUS_COMPONENT
45 ACPI_MODULE_NAME("bus");
47 struct acpi_device *acpi_root;
48 struct proc_dir_entry *acpi_root_dir;
49 EXPORT_SYMBOL(acpi_root_dir);
51 #define STRUCT_TO_INT(s) (*((int*)&s))
53 static int set_power_nocheck(const struct dmi_system_id *id)
55 printk(KERN_NOTICE PREFIX "%s detected - "
56 "disable power check in power transistion\n", id->ident);
57 acpi_power_nocheck = 1;
58 return 0;
60 static struct dmi_system_id __cpuinitdata power_nocheck_dmi_table[] = {
62 set_power_nocheck, "HP Pavilion 05", {
63 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
64 DMI_MATCH(DMI_SYS_VENDOR, "HP Pavilion 05"),
65 DMI_MATCH(DMI_PRODUCT_VERSION, "2001211RE101GLEND") }, NULL},
66 {},
70 /* --------------------------------------------------------------------------
71 Device Management
72 -------------------------------------------------------------------------- */
74 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
76 acpi_status status = AE_OK;
79 if (!device)
80 return -EINVAL;
82 /* TBD: Support fixed-feature devices */
84 status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
85 if (ACPI_FAILURE(status) || !*device) {
86 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
87 handle));
88 return -ENODEV;
91 return 0;
94 EXPORT_SYMBOL(acpi_bus_get_device);
96 int acpi_bus_get_status(struct acpi_device *device)
98 acpi_status status = AE_OK;
99 unsigned long long sta = 0;
102 if (!device)
103 return -EINVAL;
106 * Evaluate _STA if present.
108 if (device->flags.dynamic_status) {
109 status =
110 acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
111 if (ACPI_FAILURE(status))
112 return -ENODEV;
113 STRUCT_TO_INT(device->status) = (int)sta;
117 * According to ACPI spec some device can be present and functional
118 * even if the parent is not present but functional.
119 * In such conditions the child device should not inherit the status
120 * from the parent.
122 else
123 STRUCT_TO_INT(device->status) =
124 ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
125 ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
127 if (device->status.functional && !device->status.present) {
128 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
129 "functional but not present;\n",
130 device->pnp.bus_id,
131 (u32) STRUCT_TO_INT(device->status)));
134 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
135 device->pnp.bus_id,
136 (u32) STRUCT_TO_INT(device->status)));
138 return 0;
141 EXPORT_SYMBOL(acpi_bus_get_status);
143 void acpi_bus_private_data_handler(acpi_handle handle,
144 u32 function, void *context)
146 return;
148 EXPORT_SYMBOL(acpi_bus_private_data_handler);
150 int acpi_bus_get_private_data(acpi_handle handle, void **data)
152 acpi_status status = AE_OK;
154 if (!*data)
155 return -EINVAL;
157 status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
158 if (ACPI_FAILURE(status) || !*data) {
159 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
160 handle));
161 return -ENODEV;
164 return 0;
166 EXPORT_SYMBOL(acpi_bus_get_private_data);
168 /* --------------------------------------------------------------------------
169 Power Management
170 -------------------------------------------------------------------------- */
172 int acpi_bus_get_power(acpi_handle handle, int *state)
174 int result = 0;
175 acpi_status status = 0;
176 struct acpi_device *device = NULL;
177 unsigned long long psc = 0;
180 result = acpi_bus_get_device(handle, &device);
181 if (result)
182 return result;
184 *state = ACPI_STATE_UNKNOWN;
186 if (!device->flags.power_manageable) {
187 /* TBD: Non-recursive algorithm for walking up hierarchy */
188 if (device->parent)
189 *state = device->parent->power.state;
190 else
191 *state = ACPI_STATE_D0;
192 } else {
194 * Get the device's power state either directly (via _PSC) or
195 * indirectly (via power resources).
197 if (device->power.flags.explicit_get) {
198 status = acpi_evaluate_integer(device->handle, "_PSC",
199 NULL, &psc);
200 if (ACPI_FAILURE(status))
201 return -ENODEV;
202 device->power.state = (int)psc;
203 } else if (device->power.flags.power_resources) {
204 result = acpi_power_get_inferred_state(device);
205 if (result)
206 return result;
209 *state = device->power.state;
212 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
213 device->pnp.bus_id, device->power.state));
215 return 0;
218 EXPORT_SYMBOL(acpi_bus_get_power);
220 int acpi_bus_set_power(acpi_handle handle, int state)
222 int result = 0;
223 acpi_status status = AE_OK;
224 struct acpi_device *device = NULL;
225 char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
228 result = acpi_bus_get_device(handle, &device);
229 if (result)
230 return result;
232 if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
233 return -EINVAL;
235 /* Make sure this is a valid target state */
237 if (!device->flags.power_manageable) {
238 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
239 kobject_name(&device->dev.kobj)));
240 return -ENODEV;
243 * Get device's current power state
245 if (!acpi_power_nocheck) {
247 * Maybe the incorrect power state is returned on the bogus
248 * bios, which is different with the real power state.
249 * For example: the bios returns D0 state and the real power
250 * state is D3. OS expects to set the device to D0 state. In
251 * such case if OS uses the power state returned by the BIOS,
252 * the device can't be transisted to the correct power state.
253 * So if the acpi_power_nocheck is set, it is unnecessary to
254 * get the power state by calling acpi_bus_get_power.
256 acpi_bus_get_power(device->handle, &device->power.state);
258 if ((state == device->power.state) && !device->flags.force_power_state) {
259 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
260 state));
261 return 0;
264 if (!device->power.states[state].flags.valid) {
265 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
266 return -ENODEV;
268 if (device->parent && (state < device->parent->power.state)) {
269 printk(KERN_WARNING PREFIX
270 "Cannot set device to a higher-powered"
271 " state than parent\n");
272 return -ENODEV;
276 * Transition Power
277 * ----------------
278 * On transitions to a high-powered state we first apply power (via
279 * power resources) then evalute _PSx. Conversly for transitions to
280 * a lower-powered state.
282 if (state < device->power.state) {
283 if (device->power.flags.power_resources) {
284 result = acpi_power_transition(device, state);
285 if (result)
286 goto end;
288 if (device->power.states[state].flags.explicit_set) {
289 status = acpi_evaluate_object(device->handle,
290 object_name, NULL, NULL);
291 if (ACPI_FAILURE(status)) {
292 result = -ENODEV;
293 goto end;
296 } else {
297 if (device->power.states[state].flags.explicit_set) {
298 status = acpi_evaluate_object(device->handle,
299 object_name, NULL, NULL);
300 if (ACPI_FAILURE(status)) {
301 result = -ENODEV;
302 goto end;
305 if (device->power.flags.power_resources) {
306 result = acpi_power_transition(device, state);
307 if (result)
308 goto end;
312 end:
313 if (result)
314 printk(KERN_WARNING PREFIX
315 "Device [%s] failed to transition to D%d\n",
316 device->pnp.bus_id, state);
317 else {
318 device->power.state = state;
319 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
320 "Device [%s] transitioned to D%d\n",
321 device->pnp.bus_id, state));
324 return result;
327 EXPORT_SYMBOL(acpi_bus_set_power);
329 bool acpi_bus_power_manageable(acpi_handle handle)
331 struct acpi_device *device;
332 int result;
334 result = acpi_bus_get_device(handle, &device);
335 return result ? false : device->flags.power_manageable;
338 EXPORT_SYMBOL(acpi_bus_power_manageable);
340 bool acpi_bus_can_wakeup(acpi_handle handle)
342 struct acpi_device *device;
343 int result;
345 result = acpi_bus_get_device(handle, &device);
346 return result ? false : device->wakeup.flags.valid;
349 EXPORT_SYMBOL(acpi_bus_can_wakeup);
351 /* --------------------------------------------------------------------------
352 Event Management
353 -------------------------------------------------------------------------- */
355 #ifdef CONFIG_ACPI_PROC_EVENT
356 static DEFINE_SPINLOCK(acpi_bus_event_lock);
358 LIST_HEAD(acpi_bus_event_list);
359 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
361 extern int event_is_open;
363 int acpi_bus_generate_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
365 struct acpi_bus_event *event;
366 unsigned long flags = 0;
368 /* drop event on the floor if no one's listening */
369 if (!event_is_open)
370 return 0;
372 event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
373 if (!event)
374 return -ENOMEM;
376 strcpy(event->device_class, device_class);
377 strcpy(event->bus_id, bus_id);
378 event->type = type;
379 event->data = data;
381 spin_lock_irqsave(&acpi_bus_event_lock, flags);
382 list_add_tail(&event->node, &acpi_bus_event_list);
383 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
385 wake_up_interruptible(&acpi_bus_event_queue);
387 return 0;
391 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
393 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
395 if (!device)
396 return -EINVAL;
397 return acpi_bus_generate_proc_event4(device->pnp.device_class,
398 device->pnp.bus_id, type, data);
401 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
403 int acpi_bus_receive_event(struct acpi_bus_event *event)
405 unsigned long flags = 0;
406 struct acpi_bus_event *entry = NULL;
408 DECLARE_WAITQUEUE(wait, current);
411 if (!event)
412 return -EINVAL;
414 if (list_empty(&acpi_bus_event_list)) {
416 set_current_state(TASK_INTERRUPTIBLE);
417 add_wait_queue(&acpi_bus_event_queue, &wait);
419 if (list_empty(&acpi_bus_event_list))
420 schedule();
422 remove_wait_queue(&acpi_bus_event_queue, &wait);
423 set_current_state(TASK_RUNNING);
425 if (signal_pending(current))
426 return -ERESTARTSYS;
429 spin_lock_irqsave(&acpi_bus_event_lock, flags);
430 if (!list_empty(&acpi_bus_event_list)) {
431 entry = list_entry(acpi_bus_event_list.next,
432 struct acpi_bus_event, node);
433 list_del(&entry->node);
435 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
437 if (!entry)
438 return -ENODEV;
440 memcpy(event, entry, sizeof(struct acpi_bus_event));
442 kfree(entry);
444 return 0;
447 #endif /* CONFIG_ACPI_PROC_EVENT */
449 /* --------------------------------------------------------------------------
450 Notification Handling
451 -------------------------------------------------------------------------- */
453 static int acpi_bus_check_device(struct acpi_device *device)
455 acpi_status status = 0;
456 struct acpi_device_status old_status;
459 if (!device)
460 return -EINVAL;
462 old_status = device->status;
465 * Make sure this device's parent is present before we go about
466 * messing with the device.
468 if (device->parent && !device->parent->status.present) {
469 device->status = device->parent->status;
470 return 0;
473 status = acpi_bus_get_status(device);
474 if (ACPI_FAILURE(status))
475 return -ENODEV;
477 if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
478 return 0;
481 * Device Insertion/Removal
483 if ((device->status.present) && !(old_status.present)) {
484 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
485 /* TBD: Handle device insertion */
486 } else if (!(device->status.present) && (old_status.present)) {
487 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
488 /* TBD: Handle device removal */
491 return 0;
494 static int acpi_bus_check_scope(struct acpi_device *device)
496 int result = 0;
498 if (!device)
499 return -EINVAL;
501 /* Status Change? */
502 result = acpi_bus_check_device(device);
503 if (result)
504 return result;
507 * TBD: Enumerate child devices within this device's scope and
508 * run acpi_bus_check_device()'s on them.
511 return 0;
514 static BLOCKING_NOTIFIER_HEAD(acpi_bus_notify_list);
515 int register_acpi_bus_notifier(struct notifier_block *nb)
517 return blocking_notifier_chain_register(&acpi_bus_notify_list, nb);
519 EXPORT_SYMBOL_GPL(register_acpi_bus_notifier);
521 void unregister_acpi_bus_notifier(struct notifier_block *nb)
523 blocking_notifier_chain_unregister(&acpi_bus_notify_list, nb);
525 EXPORT_SYMBOL_GPL(unregister_acpi_bus_notifier);
528 * acpi_bus_notify
529 * ---------------
530 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
532 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
534 int result = 0;
535 struct acpi_device *device = NULL;
536 struct acpi_driver *driver;
538 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
539 type, handle));
541 blocking_notifier_call_chain(&acpi_bus_notify_list,
542 type, (void *)handle);
544 if (acpi_bus_get_device(handle, &device))
545 return;
547 switch (type) {
549 case ACPI_NOTIFY_BUS_CHECK:
550 result = acpi_bus_check_scope(device);
552 * TBD: We'll need to outsource certain events to non-ACPI
553 * drivers via the device manager (device.c).
555 break;
557 case ACPI_NOTIFY_DEVICE_CHECK:
558 result = acpi_bus_check_device(device);
560 * TBD: We'll need to outsource certain events to non-ACPI
561 * drivers via the device manager (device.c).
563 break;
565 case ACPI_NOTIFY_DEVICE_WAKE:
566 /* TBD */
567 break;
569 case ACPI_NOTIFY_EJECT_REQUEST:
570 /* TBD */
571 break;
573 case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
574 /* TBD: Exactly what does 'light' mean? */
575 break;
577 case ACPI_NOTIFY_FREQUENCY_MISMATCH:
578 /* TBD */
579 break;
581 case ACPI_NOTIFY_BUS_MODE_MISMATCH:
582 /* TBD */
583 break;
585 case ACPI_NOTIFY_POWER_FAULT:
586 /* TBD */
587 break;
589 default:
590 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
591 "Received unknown/unsupported notification [%08x]\n",
592 type));
593 break;
596 driver = device->driver;
597 if (driver && driver->ops.notify &&
598 (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
599 driver->ops.notify(device, type);
602 /* --------------------------------------------------------------------------
603 Initialization/Cleanup
604 -------------------------------------------------------------------------- */
606 static int __init acpi_bus_init_irq(void)
608 acpi_status status = AE_OK;
609 union acpi_object arg = { ACPI_TYPE_INTEGER };
610 struct acpi_object_list arg_list = { 1, &arg };
611 char *message = NULL;
615 * Let the system know what interrupt model we are using by
616 * evaluating the \_PIC object, if exists.
619 switch (acpi_irq_model) {
620 case ACPI_IRQ_MODEL_PIC:
621 message = "PIC";
622 break;
623 case ACPI_IRQ_MODEL_IOAPIC:
624 message = "IOAPIC";
625 break;
626 case ACPI_IRQ_MODEL_IOSAPIC:
627 message = "IOSAPIC";
628 break;
629 case ACPI_IRQ_MODEL_PLATFORM:
630 message = "platform specific model";
631 break;
632 default:
633 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
634 return -ENODEV;
637 printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
639 arg.integer.value = acpi_irq_model;
641 status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
642 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
643 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
644 return -ENODEV;
647 return 0;
650 u8 acpi_gbl_permanent_mmap;
653 void __init acpi_early_init(void)
655 acpi_status status = AE_OK;
657 if (acpi_disabled)
658 return;
660 printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
662 /* enable workarounds, unless strict ACPI spec. compliance */
663 if (!acpi_strict)
664 acpi_gbl_enable_interpreter_slack = TRUE;
666 acpi_gbl_permanent_mmap = 1;
668 status = acpi_reallocate_root_table();
669 if (ACPI_FAILURE(status)) {
670 printk(KERN_ERR PREFIX
671 "Unable to reallocate ACPI tables\n");
672 goto error0;
675 status = acpi_initialize_subsystem();
676 if (ACPI_FAILURE(status)) {
677 printk(KERN_ERR PREFIX
678 "Unable to initialize the ACPI Interpreter\n");
679 goto error0;
682 status = acpi_load_tables();
683 if (ACPI_FAILURE(status)) {
684 printk(KERN_ERR PREFIX
685 "Unable to load the System Description Tables\n");
686 goto error0;
689 #ifdef CONFIG_X86
690 if (!acpi_ioapic) {
691 /* compatible (0) means level (3) */
692 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
693 acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
694 acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
696 /* Set PIC-mode SCI trigger type */
697 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
698 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
699 } else {
701 * now that acpi_gbl_FADT is initialized,
702 * update it with result from INT_SRC_OVR parsing
704 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
706 #endif
708 status =
709 acpi_enable_subsystem(~
710 (ACPI_NO_HARDWARE_INIT |
711 ACPI_NO_ACPI_ENABLE));
712 if (ACPI_FAILURE(status)) {
713 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
714 goto error0;
717 return;
719 error0:
720 disable_acpi();
721 return;
724 static int __init acpi_bus_init(void)
726 int result = 0;
727 acpi_status status = AE_OK;
728 extern acpi_status acpi_os_initialize1(void);
730 acpi_os_initialize1();
732 status =
733 acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
734 if (ACPI_FAILURE(status)) {
735 printk(KERN_ERR PREFIX
736 "Unable to start the ACPI Interpreter\n");
737 goto error1;
741 * ACPI 2.0 requires the EC driver to be loaded and work before
742 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
743 * is called).
745 * This is accomplished by looking for the ECDT table, and getting
746 * the EC parameters out of that.
748 status = acpi_ec_ecdt_probe();
749 /* Ignore result. Not having an ECDT is not fatal. */
751 status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
752 if (ACPI_FAILURE(status)) {
753 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
754 goto error1;
758 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
759 * is necessary to enable it as early as possible.
761 acpi_boot_ec_enable();
763 printk(KERN_INFO PREFIX "Interpreter enabled\n");
765 /* Initialize sleep structures */
766 acpi_sleep_init();
769 * Get the system interrupt model and evaluate \_PIC.
771 result = acpi_bus_init_irq();
772 if (result)
773 goto error1;
776 * Register the for all standard device notifications.
778 status =
779 acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
780 &acpi_bus_notify, NULL);
781 if (ACPI_FAILURE(status)) {
782 printk(KERN_ERR PREFIX
783 "Unable to register for device notifications\n");
784 goto error1;
788 * Create the top ACPI proc directory
790 acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
792 return 0;
794 /* Mimic structured exception handling */
795 error1:
796 acpi_terminate();
797 return -ENODEV;
800 struct kobject *acpi_kobj;
802 static int __init acpi_init(void)
804 int result = 0;
807 if (acpi_disabled) {
808 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
809 return -ENODEV;
812 acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
813 if (!acpi_kobj) {
814 printk(KERN_WARNING "%s: kset create error\n", __func__);
815 acpi_kobj = NULL;
818 init_acpi_device_notify();
819 result = acpi_bus_init();
821 if (!result) {
822 pci_mmcfg_late_init();
823 if (!(pm_flags & PM_APM))
824 pm_flags |= PM_ACPI;
825 else {
826 printk(KERN_INFO PREFIX
827 "APM is already active, exiting\n");
828 disable_acpi();
829 result = -ENODEV;
831 } else
832 disable_acpi();
834 if (acpi_disabled)
835 return result;
838 * If the laptop falls into the DMI check table, the power state check
839 * will be disabled in the course of device power transistion.
841 dmi_check_system(power_nocheck_dmi_table);
843 acpi_scan_init();
844 acpi_ec_init();
845 acpi_power_init();
846 acpi_system_init();
847 acpi_debug_init();
848 acpi_sleep_proc_init();
849 acpi_wakeup_device_init();
850 return result;
853 subsys_initcall(acpi_init);