acpi/x86: introduce __apci_map_table, v4
[linux-2.6/mini2440.git] / drivers / acpi / bus.c
blob765fd1c56cd66bc445ab5228f562177b9eb469e1
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 #define _COMPONENT ACPI_BUS_COMPONENT
43 ACPI_MODULE_NAME("bus");
45 struct acpi_device *acpi_root;
46 struct proc_dir_entry *acpi_root_dir;
47 EXPORT_SYMBOL(acpi_root_dir);
49 #define STRUCT_TO_INT(s) (*((int*)&s))
51 static int set_power_nocheck(const struct dmi_system_id *id)
53 printk(KERN_NOTICE PREFIX "%s detected - "
54 "disable power check in power transistion\n", id->ident);
55 acpi_power_nocheck = 1;
56 return 0;
58 static struct dmi_system_id __cpuinitdata power_nocheck_dmi_table[] = {
60 set_power_nocheck, "HP Pavilion 05", {
61 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
62 DMI_MATCH(DMI_SYS_VENDOR, "HP Pavilion 05"),
63 DMI_MATCH(DMI_PRODUCT_VERSION, "2001211RE101GLEND") }, NULL},
64 {},
68 /* --------------------------------------------------------------------------
69 Device Management
70 -------------------------------------------------------------------------- */
72 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
74 acpi_status status = AE_OK;
77 if (!device)
78 return -EINVAL;
80 /* TBD: Support fixed-feature devices */
82 status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
83 if (ACPI_FAILURE(status) || !*device) {
84 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
85 handle));
86 return -ENODEV;
89 return 0;
92 EXPORT_SYMBOL(acpi_bus_get_device);
94 int acpi_bus_get_status(struct acpi_device *device)
96 acpi_status status = AE_OK;
97 unsigned long long sta = 0;
100 if (!device)
101 return -EINVAL;
104 * Evaluate _STA if present.
106 if (device->flags.dynamic_status) {
107 status =
108 acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
109 if (ACPI_FAILURE(status))
110 return -ENODEV;
111 STRUCT_TO_INT(device->status) = (int)sta;
115 * According to ACPI spec some device can be present and functional
116 * even if the parent is not present but functional.
117 * In such conditions the child device should not inherit the status
118 * from the parent.
120 else
121 STRUCT_TO_INT(device->status) =
122 ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
123 ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
125 if (device->status.functional && !device->status.present) {
126 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
127 "functional but not present;\n",
128 device->pnp.bus_id,
129 (u32) STRUCT_TO_INT(device->status)));
132 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
133 device->pnp.bus_id,
134 (u32) STRUCT_TO_INT(device->status)));
136 return 0;
139 EXPORT_SYMBOL(acpi_bus_get_status);
141 void acpi_bus_private_data_handler(acpi_handle handle,
142 u32 function, void *context)
144 return;
146 EXPORT_SYMBOL(acpi_bus_private_data_handler);
148 int acpi_bus_get_private_data(acpi_handle handle, void **data)
150 acpi_status status = AE_OK;
152 if (!*data)
153 return -EINVAL;
155 status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
156 if (ACPI_FAILURE(status) || !*data) {
157 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
158 handle));
159 return -ENODEV;
162 return 0;
164 EXPORT_SYMBOL(acpi_bus_get_private_data);
166 /* --------------------------------------------------------------------------
167 Power Management
168 -------------------------------------------------------------------------- */
170 int acpi_bus_get_power(acpi_handle handle, int *state)
172 int result = 0;
173 acpi_status status = 0;
174 struct acpi_device *device = NULL;
175 unsigned long long psc = 0;
178 result = acpi_bus_get_device(handle, &device);
179 if (result)
180 return result;
182 *state = ACPI_STATE_UNKNOWN;
184 if (!device->flags.power_manageable) {
185 /* TBD: Non-recursive algorithm for walking up hierarchy */
186 if (device->parent)
187 *state = device->parent->power.state;
188 else
189 *state = ACPI_STATE_D0;
190 } else {
192 * Get the device's power state either directly (via _PSC) or
193 * indirectly (via power resources).
195 if (device->power.flags.explicit_get) {
196 status = acpi_evaluate_integer(device->handle, "_PSC",
197 NULL, &psc);
198 if (ACPI_FAILURE(status))
199 return -ENODEV;
200 device->power.state = (int)psc;
201 } else if (device->power.flags.power_resources) {
202 result = acpi_power_get_inferred_state(device);
203 if (result)
204 return result;
207 *state = device->power.state;
210 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
211 device->pnp.bus_id, device->power.state));
213 return 0;
216 EXPORT_SYMBOL(acpi_bus_get_power);
218 int acpi_bus_set_power(acpi_handle handle, int state)
220 int result = 0;
221 acpi_status status = AE_OK;
222 struct acpi_device *device = NULL;
223 char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
226 result = acpi_bus_get_device(handle, &device);
227 if (result)
228 return result;
230 if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
231 return -EINVAL;
233 /* Make sure this is a valid target state */
235 if (!device->flags.power_manageable) {
236 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
237 kobject_name(&device->dev.kobj)));
238 return -ENODEV;
241 * Get device's current power state
243 if (!acpi_power_nocheck) {
245 * Maybe the incorrect power state is returned on the bogus
246 * bios, which is different with the real power state.
247 * For example: the bios returns D0 state and the real power
248 * state is D3. OS expects to set the device to D0 state. In
249 * such case if OS uses the power state returned by the BIOS,
250 * the device can't be transisted to the correct power state.
251 * So if the acpi_power_nocheck is set, it is unnecessary to
252 * get the power state by calling acpi_bus_get_power.
254 acpi_bus_get_power(device->handle, &device->power.state);
256 if ((state == device->power.state) && !device->flags.force_power_state) {
257 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
258 state));
259 return 0;
262 if (!device->power.states[state].flags.valid) {
263 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
264 return -ENODEV;
266 if (device->parent && (state < device->parent->power.state)) {
267 printk(KERN_WARNING PREFIX
268 "Cannot set device to a higher-powered"
269 " state than parent\n");
270 return -ENODEV;
274 * Transition Power
275 * ----------------
276 * On transitions to a high-powered state we first apply power (via
277 * power resources) then evalute _PSx. Conversly for transitions to
278 * a lower-powered state.
280 if (state < device->power.state) {
281 if (device->power.flags.power_resources) {
282 result = acpi_power_transition(device, state);
283 if (result)
284 goto end;
286 if (device->power.states[state].flags.explicit_set) {
287 status = acpi_evaluate_object(device->handle,
288 object_name, NULL, NULL);
289 if (ACPI_FAILURE(status)) {
290 result = -ENODEV;
291 goto end;
294 } else {
295 if (device->power.states[state].flags.explicit_set) {
296 status = acpi_evaluate_object(device->handle,
297 object_name, NULL, NULL);
298 if (ACPI_FAILURE(status)) {
299 result = -ENODEV;
300 goto end;
303 if (device->power.flags.power_resources) {
304 result = acpi_power_transition(device, state);
305 if (result)
306 goto end;
310 end:
311 if (result)
312 printk(KERN_WARNING PREFIX
313 "Transitioning device [%s] to D%d\n",
314 device->pnp.bus_id, state);
315 else {
316 device->power.state = state;
317 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
318 "Device [%s] transitioned to D%d\n",
319 device->pnp.bus_id, state));
322 return result;
325 EXPORT_SYMBOL(acpi_bus_set_power);
327 bool acpi_bus_power_manageable(acpi_handle handle)
329 struct acpi_device *device;
330 int result;
332 result = acpi_bus_get_device(handle, &device);
333 return result ? false : device->flags.power_manageable;
336 EXPORT_SYMBOL(acpi_bus_power_manageable);
338 bool acpi_bus_can_wakeup(acpi_handle handle)
340 struct acpi_device *device;
341 int result;
343 result = acpi_bus_get_device(handle, &device);
344 return result ? false : device->wakeup.flags.valid;
347 EXPORT_SYMBOL(acpi_bus_can_wakeup);
349 /* --------------------------------------------------------------------------
350 Event Management
351 -------------------------------------------------------------------------- */
353 #ifdef CONFIG_ACPI_PROC_EVENT
354 static DEFINE_SPINLOCK(acpi_bus_event_lock);
356 LIST_HEAD(acpi_bus_event_list);
357 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
359 extern int event_is_open;
361 int acpi_bus_generate_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
363 struct acpi_bus_event *event;
364 unsigned long flags = 0;
366 /* drop event on the floor if no one's listening */
367 if (!event_is_open)
368 return 0;
370 event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
371 if (!event)
372 return -ENOMEM;
374 strcpy(event->device_class, device_class);
375 strcpy(event->bus_id, bus_id);
376 event->type = type;
377 event->data = data;
379 spin_lock_irqsave(&acpi_bus_event_lock, flags);
380 list_add_tail(&event->node, &acpi_bus_event_list);
381 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
383 wake_up_interruptible(&acpi_bus_event_queue);
385 return 0;
389 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
391 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
393 if (!device)
394 return -EINVAL;
395 return acpi_bus_generate_proc_event4(device->pnp.device_class,
396 device->pnp.bus_id, type, data);
399 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
401 int acpi_bus_receive_event(struct acpi_bus_event *event)
403 unsigned long flags = 0;
404 struct acpi_bus_event *entry = NULL;
406 DECLARE_WAITQUEUE(wait, current);
409 if (!event)
410 return -EINVAL;
412 if (list_empty(&acpi_bus_event_list)) {
414 set_current_state(TASK_INTERRUPTIBLE);
415 add_wait_queue(&acpi_bus_event_queue, &wait);
417 if (list_empty(&acpi_bus_event_list))
418 schedule();
420 remove_wait_queue(&acpi_bus_event_queue, &wait);
421 set_current_state(TASK_RUNNING);
423 if (signal_pending(current))
424 return -ERESTARTSYS;
427 spin_lock_irqsave(&acpi_bus_event_lock, flags);
428 if (!list_empty(&acpi_bus_event_list)) {
429 entry = list_entry(acpi_bus_event_list.next,
430 struct acpi_bus_event, node);
431 list_del(&entry->node);
433 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
435 if (!entry)
436 return -ENODEV;
438 memcpy(event, entry, sizeof(struct acpi_bus_event));
440 kfree(entry);
442 return 0;
445 #endif /* CONFIG_ACPI_PROC_EVENT */
447 /* --------------------------------------------------------------------------
448 Notification Handling
449 -------------------------------------------------------------------------- */
451 static int
452 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
454 acpi_status status = 0;
455 struct acpi_device_status old_status;
458 if (!device)
459 return -EINVAL;
461 if (status_changed)
462 *status_changed = 0;
464 old_status = device->status;
467 * Make sure this device's parent is present before we go about
468 * messing with the device.
470 if (device->parent && !device->parent->status.present) {
471 device->status = device->parent->status;
472 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
473 if (status_changed)
474 *status_changed = 1;
476 return 0;
479 status = acpi_bus_get_status(device);
480 if (ACPI_FAILURE(status))
481 return -ENODEV;
483 if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
484 return 0;
486 if (status_changed)
487 *status_changed = 1;
490 * Device Insertion/Removal
492 if ((device->status.present) && !(old_status.present)) {
493 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
494 /* TBD: Handle device insertion */
495 } else if (!(device->status.present) && (old_status.present)) {
496 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
497 /* TBD: Handle device removal */
500 return 0;
503 static int acpi_bus_check_scope(struct acpi_device *device)
505 int result = 0;
506 int status_changed = 0;
509 if (!device)
510 return -EINVAL;
512 /* Status Change? */
513 result = acpi_bus_check_device(device, &status_changed);
514 if (result)
515 return result;
517 if (!status_changed)
518 return 0;
521 * TBD: Enumerate child devices within this device's scope and
522 * run acpi_bus_check_device()'s on them.
525 return 0;
528 static BLOCKING_NOTIFIER_HEAD(acpi_bus_notify_list);
529 int register_acpi_bus_notifier(struct notifier_block *nb)
531 return blocking_notifier_chain_register(&acpi_bus_notify_list, nb);
533 EXPORT_SYMBOL_GPL(register_acpi_bus_notifier);
535 void unregister_acpi_bus_notifier(struct notifier_block *nb)
537 blocking_notifier_chain_unregister(&acpi_bus_notify_list, nb);
539 EXPORT_SYMBOL_GPL(unregister_acpi_bus_notifier);
542 * acpi_bus_notify
543 * ---------------
544 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
546 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
548 int result = 0;
549 struct acpi_device *device = NULL;
551 blocking_notifier_call_chain(&acpi_bus_notify_list,
552 type, (void *)handle);
554 if (acpi_bus_get_device(handle, &device))
555 return;
557 switch (type) {
559 case ACPI_NOTIFY_BUS_CHECK:
560 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
561 "Received BUS CHECK notification for device [%s]\n",
562 device->pnp.bus_id));
563 result = acpi_bus_check_scope(device);
565 * TBD: We'll need to outsource certain events to non-ACPI
566 * drivers via the device manager (device.c).
568 break;
570 case ACPI_NOTIFY_DEVICE_CHECK:
571 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
572 "Received DEVICE CHECK notification for device [%s]\n",
573 device->pnp.bus_id));
574 result = acpi_bus_check_device(device, NULL);
576 * TBD: We'll need to outsource certain events to non-ACPI
577 * drivers via the device manager (device.c).
579 break;
581 case ACPI_NOTIFY_DEVICE_WAKE:
582 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
583 "Received DEVICE WAKE notification for device [%s]\n",
584 device->pnp.bus_id));
585 /* TBD */
586 break;
588 case ACPI_NOTIFY_EJECT_REQUEST:
589 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
590 "Received EJECT REQUEST notification for device [%s]\n",
591 device->pnp.bus_id));
592 /* TBD */
593 break;
595 case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
596 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
597 "Received DEVICE CHECK LIGHT notification for device [%s]\n",
598 device->pnp.bus_id));
599 /* TBD: Exactly what does 'light' mean? */
600 break;
602 case ACPI_NOTIFY_FREQUENCY_MISMATCH:
603 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
604 "Received FREQUENCY MISMATCH notification for device [%s]\n",
605 device->pnp.bus_id));
606 /* TBD */
607 break;
609 case ACPI_NOTIFY_BUS_MODE_MISMATCH:
610 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
611 "Received BUS MODE MISMATCH notification for device [%s]\n",
612 device->pnp.bus_id));
613 /* TBD */
614 break;
616 case ACPI_NOTIFY_POWER_FAULT:
617 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
618 "Received POWER FAULT notification for device [%s]\n",
619 device->pnp.bus_id));
620 /* TBD */
621 break;
623 default:
624 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
625 "Received unknown/unsupported notification [%08x]\n",
626 type));
627 break;
630 return;
633 /* --------------------------------------------------------------------------
634 Initialization/Cleanup
635 -------------------------------------------------------------------------- */
637 static int __init acpi_bus_init_irq(void)
639 acpi_status status = AE_OK;
640 union acpi_object arg = { ACPI_TYPE_INTEGER };
641 struct acpi_object_list arg_list = { 1, &arg };
642 char *message = NULL;
646 * Let the system know what interrupt model we are using by
647 * evaluating the \_PIC object, if exists.
650 switch (acpi_irq_model) {
651 case ACPI_IRQ_MODEL_PIC:
652 message = "PIC";
653 break;
654 case ACPI_IRQ_MODEL_IOAPIC:
655 message = "IOAPIC";
656 break;
657 case ACPI_IRQ_MODEL_IOSAPIC:
658 message = "IOSAPIC";
659 break;
660 case ACPI_IRQ_MODEL_PLATFORM:
661 message = "platform specific model";
662 break;
663 default:
664 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
665 return -ENODEV;
668 printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
670 arg.integer.value = acpi_irq_model;
672 status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
673 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
674 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
675 return -ENODEV;
678 return 0;
681 u8 acpi_gbl_permanent_mmap;
684 void __init acpi_early_init(void)
686 acpi_status status = AE_OK;
688 if (acpi_disabled)
689 return;
691 printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
693 /* enable workarounds, unless strict ACPI spec. compliance */
694 if (!acpi_strict)
695 acpi_gbl_enable_interpreter_slack = TRUE;
697 acpi_gbl_permanent_mmap = 1;
699 status = acpi_reallocate_root_table();
700 if (ACPI_FAILURE(status)) {
701 printk(KERN_ERR PREFIX
702 "Unable to reallocate ACPI tables\n");
703 goto error0;
706 status = acpi_initialize_subsystem();
707 if (ACPI_FAILURE(status)) {
708 printk(KERN_ERR PREFIX
709 "Unable to initialize the ACPI Interpreter\n");
710 goto error0;
713 status = acpi_load_tables();
714 if (ACPI_FAILURE(status)) {
715 printk(KERN_ERR PREFIX
716 "Unable to load the System Description Tables\n");
717 goto error0;
720 #ifdef CONFIG_X86
721 if (!acpi_ioapic) {
722 /* compatible (0) means level (3) */
723 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
724 acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
725 acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
727 /* Set PIC-mode SCI trigger type */
728 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
729 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
730 } else {
732 * now that acpi_gbl_FADT is initialized,
733 * update it with result from INT_SRC_OVR parsing
735 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
737 #endif
739 status =
740 acpi_enable_subsystem(~
741 (ACPI_NO_HARDWARE_INIT |
742 ACPI_NO_ACPI_ENABLE));
743 if (ACPI_FAILURE(status)) {
744 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
745 goto error0;
748 return;
750 error0:
751 disable_acpi();
752 return;
755 static int __init acpi_bus_init(void)
757 int result = 0;
758 acpi_status status = AE_OK;
759 extern acpi_status acpi_os_initialize1(void);
762 status = acpi_os_initialize1();
764 status =
765 acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
766 if (ACPI_FAILURE(status)) {
767 printk(KERN_ERR PREFIX
768 "Unable to start the ACPI Interpreter\n");
769 goto error1;
772 if (ACPI_FAILURE(status)) {
773 printk(KERN_ERR PREFIX
774 "Unable to initialize ACPI OS objects\n");
775 goto error1;
779 * ACPI 2.0 requires the EC driver to be loaded and work before
780 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
781 * is called).
783 * This is accomplished by looking for the ECDT table, and getting
784 * the EC parameters out of that.
786 status = acpi_ec_ecdt_probe();
787 /* Ignore result. Not having an ECDT is not fatal. */
789 status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
790 if (ACPI_FAILURE(status)) {
791 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
792 goto error1;
796 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
797 * is necessary to enable it as early as possible.
799 acpi_boot_ec_enable();
801 printk(KERN_INFO PREFIX "Interpreter enabled\n");
803 /* Initialize sleep structures */
804 acpi_sleep_init();
807 * Get the system interrupt model and evaluate \_PIC.
809 result = acpi_bus_init_irq();
810 if (result)
811 goto error1;
814 * Register the for all standard device notifications.
816 status =
817 acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
818 &acpi_bus_notify, NULL);
819 if (ACPI_FAILURE(status)) {
820 printk(KERN_ERR PREFIX
821 "Unable to register for device notifications\n");
822 goto error1;
826 * Create the top ACPI proc directory
828 acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
830 return 0;
832 /* Mimic structured exception handling */
833 error1:
834 acpi_terminate();
835 return -ENODEV;
838 struct kobject *acpi_kobj;
840 static int __init acpi_init(void)
842 int result = 0;
845 if (acpi_disabled) {
846 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
847 return -ENODEV;
850 acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
851 if (!acpi_kobj) {
852 printk(KERN_WARNING "%s: kset create error\n", __func__);
853 acpi_kobj = NULL;
856 result = acpi_bus_init();
858 if (!result) {
859 pci_mmcfg_late_init();
860 if (!(pm_flags & PM_APM))
861 pm_flags |= PM_ACPI;
862 else {
863 printk(KERN_INFO PREFIX
864 "APM is already active, exiting\n");
865 disable_acpi();
866 result = -ENODEV;
868 } else
869 disable_acpi();
871 * If the laptop falls into the DMI check table, the power state check
872 * will be disabled in the course of device power transistion.
874 dmi_check_system(power_nocheck_dmi_table);
875 return result;
878 subsys_initcall(acpi_init);