Linux 2.6.16.55
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / bus.c
blob606f8733a776cf4ab3473db6a8288431f7d9bc84
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/list.h>
29 #include <linux/sched.h>
30 #include <linux/pm.h>
31 #include <linux/pm_legacy.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>
40 #define _COMPONENT ACPI_BUS_COMPONENT
41 ACPI_MODULE_NAME("acpi_bus")
42 #ifdef CONFIG_X86
43 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
44 #endif
46 FADT_DESCRIPTOR acpi_fadt;
47 EXPORT_SYMBOL(acpi_fadt);
49 struct acpi_device *acpi_root;
50 struct proc_dir_entry *acpi_root_dir;
51 EXPORT_SYMBOL(acpi_root_dir);
53 #define STRUCT_TO_INT(s) (*((int*)&s))
55 /* --------------------------------------------------------------------------
56 Device Management
57 -------------------------------------------------------------------------- */
59 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
61 acpi_status status = AE_OK;
63 ACPI_FUNCTION_TRACE("acpi_bus_get_device");
65 if (!device)
66 return_VALUE(-EINVAL);
68 /* TBD: Support fixed-feature devices */
70 status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
71 if (ACPI_FAILURE(status) || !*device) {
72 ACPI_DEBUG_PRINT((ACPI_DB_WARN, "No context for object [%p]\n",
73 handle));
74 return_VALUE(-ENODEV);
77 return_VALUE(0);
80 EXPORT_SYMBOL(acpi_bus_get_device);
82 int acpi_bus_get_status(struct acpi_device *device)
84 acpi_status status = AE_OK;
85 unsigned long sta = 0;
87 ACPI_FUNCTION_TRACE("acpi_bus_get_status");
89 if (!device)
90 return_VALUE(-EINVAL);
93 * Evaluate _STA if present.
95 if (device->flags.dynamic_status) {
96 status =
97 acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
98 if (ACPI_FAILURE(status))
99 return_VALUE(-ENODEV);
100 STRUCT_TO_INT(device->status) = (int)sta;
104 * Otherwise we assume the status of our parent (unless we don't
105 * have one, in which case status is implied).
107 else if (device->parent)
108 device->status = device->parent->status;
109 else
110 STRUCT_TO_INT(device->status) = 0x0F;
112 if (device->status.functional && !device->status.present) {
113 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
114 "functional but not present; setting present\n",
115 device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
116 device->status.present = 1;
119 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
120 device->pnp.bus_id,
121 (u32) STRUCT_TO_INT(device->status)));
123 return_VALUE(0);
126 EXPORT_SYMBOL(acpi_bus_get_status);
128 /* --------------------------------------------------------------------------
129 Power Management
130 -------------------------------------------------------------------------- */
132 int acpi_bus_get_power(acpi_handle handle, int *state)
134 int result = 0;
135 acpi_status status = 0;
136 struct acpi_device *device = NULL;
137 unsigned long psc = 0;
139 ACPI_FUNCTION_TRACE("acpi_bus_get_power");
141 result = acpi_bus_get_device(handle, &device);
142 if (result)
143 return_VALUE(result);
145 *state = ACPI_STATE_UNKNOWN;
147 if (!device->flags.power_manageable) {
148 /* TBD: Non-recursive algorithm for walking up hierarchy */
149 if (device->parent)
150 *state = device->parent->power.state;
151 else
152 *state = ACPI_STATE_D0;
153 } else {
155 * Get the device's power state either directly (via _PSC) or
156 * indirectly (via power resources).
158 if (device->power.flags.explicit_get) {
159 status = acpi_evaluate_integer(device->handle, "_PSC",
160 NULL, &psc);
161 if (ACPI_FAILURE(status))
162 return_VALUE(-ENODEV);
163 device->power.state = (int)psc;
164 } else if (device->power.flags.power_resources) {
165 result = acpi_power_get_inferred_state(device);
166 if (result)
167 return_VALUE(result);
170 *state = device->power.state;
173 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
174 device->pnp.bus_id, device->power.state));
176 return_VALUE(0);
179 EXPORT_SYMBOL(acpi_bus_get_power);
181 int acpi_bus_set_power(acpi_handle handle, int state)
183 int result = 0;
184 acpi_status status = AE_OK;
185 struct acpi_device *device = NULL;
186 char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
188 ACPI_FUNCTION_TRACE("acpi_bus_set_power");
190 result = acpi_bus_get_device(handle, &device);
191 if (result)
192 return_VALUE(result);
194 if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
195 return_VALUE(-EINVAL);
197 /* Make sure this is a valid target state */
199 if (!device->flags.power_manageable) {
200 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
201 "Device is not power manageable\n"));
202 return_VALUE(-ENODEV);
205 * Get device's current power state if it's unknown
206 * This means device power state isn't initialized or previous setting failed
208 if (device->power.state == ACPI_STATE_UNKNOWN)
209 acpi_bus_get_power(device->handle, &device->power.state);
210 if (state == device->power.state) {
211 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
212 state));
213 return_VALUE(0);
215 if (!device->power.states[state].flags.valid) {
216 ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Device does not support D%d\n",
217 state));
218 return_VALUE(-ENODEV);
220 if (device->parent && (state < device->parent->power.state)) {
221 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
222 "Cannot set device to a higher-powered state than parent\n"));
223 return_VALUE(-ENODEV);
227 * Transition Power
228 * ----------------
229 * On transitions to a high-powered state we first apply power (via
230 * power resources) then evalute _PSx. Conversly for transitions to
231 * a lower-powered state.
233 if (state < device->power.state) {
234 if (device->power.flags.power_resources) {
235 result = acpi_power_transition(device, state);
236 if (result)
237 goto end;
239 if (device->power.states[state].flags.explicit_set) {
240 status = acpi_evaluate_object(device->handle,
241 object_name, NULL, NULL);
242 if (ACPI_FAILURE(status)) {
243 result = -ENODEV;
244 goto end;
247 } else {
248 if (device->power.states[state].flags.explicit_set) {
249 status = acpi_evaluate_object(device->handle,
250 object_name, NULL, NULL);
251 if (ACPI_FAILURE(status)) {
252 result = -ENODEV;
253 goto end;
256 if (device->power.flags.power_resources) {
257 result = acpi_power_transition(device, state);
258 if (result)
259 goto end;
263 end:
264 if (result)
265 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
266 "Error transitioning device [%s] to D%d\n",
267 device->pnp.bus_id, state));
268 else
269 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
270 "Device [%s] transitioned to D%d\n",
271 device->pnp.bus_id, state));
273 return_VALUE(result);
276 EXPORT_SYMBOL(acpi_bus_set_power);
278 /* --------------------------------------------------------------------------
279 Event Management
280 -------------------------------------------------------------------------- */
282 static DEFINE_SPINLOCK(acpi_bus_event_lock);
284 LIST_HEAD(acpi_bus_event_list);
285 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
287 extern int event_is_open;
289 int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
291 struct acpi_bus_event *event = NULL;
292 unsigned long flags = 0;
294 ACPI_FUNCTION_TRACE("acpi_bus_generate_event");
296 if (!device)
297 return_VALUE(-EINVAL);
299 /* drop event on the floor if no one's listening */
300 if (!event_is_open)
301 return_VALUE(0);
303 event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
304 if (!event)
305 return_VALUE(-ENOMEM);
307 strcpy(event->device_class, device->pnp.device_class);
308 strcpy(event->bus_id, device->pnp.bus_id);
309 event->type = type;
310 event->data = data;
312 spin_lock_irqsave(&acpi_bus_event_lock, flags);
313 list_add_tail(&event->node, &acpi_bus_event_list);
314 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
316 wake_up_interruptible(&acpi_bus_event_queue);
318 return_VALUE(0);
321 EXPORT_SYMBOL(acpi_bus_generate_event);
323 int acpi_bus_receive_event(struct acpi_bus_event *event)
325 unsigned long flags = 0;
326 struct acpi_bus_event *entry = NULL;
328 DECLARE_WAITQUEUE(wait, current);
330 ACPI_FUNCTION_TRACE("acpi_bus_receive_event");
332 if (!event)
333 return_VALUE(-EINVAL);
335 if (list_empty(&acpi_bus_event_list)) {
337 set_current_state(TASK_INTERRUPTIBLE);
338 add_wait_queue(&acpi_bus_event_queue, &wait);
340 if (list_empty(&acpi_bus_event_list))
341 schedule();
343 remove_wait_queue(&acpi_bus_event_queue, &wait);
344 set_current_state(TASK_RUNNING);
346 if (signal_pending(current))
347 return_VALUE(-ERESTARTSYS);
350 spin_lock_irqsave(&acpi_bus_event_lock, flags);
351 entry =
352 list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
353 if (entry)
354 list_del(&entry->node);
355 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
357 if (!entry)
358 return_VALUE(-ENODEV);
360 memcpy(event, entry, sizeof(struct acpi_bus_event));
362 kfree(entry);
364 return_VALUE(0);
367 EXPORT_SYMBOL(acpi_bus_receive_event);
369 /* --------------------------------------------------------------------------
370 Notification Handling
371 -------------------------------------------------------------------------- */
373 static int
374 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
376 acpi_status status = 0;
377 struct acpi_device_status old_status;
379 ACPI_FUNCTION_TRACE("acpi_bus_check_device");
381 if (!device)
382 return_VALUE(-EINVAL);
384 if (status_changed)
385 *status_changed = 0;
387 old_status = device->status;
390 * Make sure this device's parent is present before we go about
391 * messing with the device.
393 if (device->parent && !device->parent->status.present) {
394 device->status = device->parent->status;
395 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
396 if (status_changed)
397 *status_changed = 1;
399 return_VALUE(0);
402 status = acpi_bus_get_status(device);
403 if (ACPI_FAILURE(status))
404 return_VALUE(-ENODEV);
406 if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
407 return_VALUE(0);
409 if (status_changed)
410 *status_changed = 1;
413 * Device Insertion/Removal
415 if ((device->status.present) && !(old_status.present)) {
416 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
417 /* TBD: Handle device insertion */
418 } else if (!(device->status.present) && (old_status.present)) {
419 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
420 /* TBD: Handle device removal */
423 return_VALUE(0);
426 static int acpi_bus_check_scope(struct acpi_device *device)
428 int result = 0;
429 int status_changed = 0;
431 ACPI_FUNCTION_TRACE("acpi_bus_check_scope");
433 if (!device)
434 return_VALUE(-EINVAL);
436 /* Status Change? */
437 result = acpi_bus_check_device(device, &status_changed);
438 if (result)
439 return_VALUE(result);
441 if (!status_changed)
442 return_VALUE(0);
445 * TBD: Enumerate child devices within this device's scope and
446 * run acpi_bus_check_device()'s on them.
449 return_VALUE(0);
453 * acpi_bus_notify
454 * ---------------
455 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
457 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
459 int result = 0;
460 struct acpi_device *device = NULL;
462 ACPI_FUNCTION_TRACE("acpi_bus_notify");
464 if (acpi_bus_get_device(handle, &device))
465 return_VOID;
467 switch (type) {
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);
475 * TBD: We'll need to outsource certain events to non-ACPI
476 * drivers via the device manager (device.c).
478 break;
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);
486 * TBD: We'll need to outsource certain events to non-ACPI
487 * drivers via the device manager (device.c).
489 break;
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;
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;
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;
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;
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;
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;
533 default:
534 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
535 "Received unknown/unsupported notification [%08x]\n",
536 type));
537 break;
540 return_VOID;
543 /* --------------------------------------------------------------------------
544 Initialization/Cleanup
545 -------------------------------------------------------------------------- */
547 static int __init acpi_bus_init_irq(void)
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;
554 ACPI_FUNCTION_TRACE("acpi_bus_init_irq");
557 * Let the system know what interrupt model we are using by
558 * evaluating the \_PIC object, if exists.
561 switch (acpi_irq_model) {
562 case ACPI_IRQ_MODEL_PIC:
563 message = "PIC";
564 break;
565 case ACPI_IRQ_MODEL_IOAPIC:
566 message = "IOAPIC";
567 break;
568 case ACPI_IRQ_MODEL_IOSAPIC:
569 message = "IOSAPIC";
570 break;
571 default:
572 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
573 return_VALUE(-ENODEV);
576 printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
578 arg.integer.value = acpi_irq_model;
580 status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
581 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
582 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PIC\n"));
583 return_VALUE(-ENODEV);
586 return_VALUE(0);
589 void __init acpi_early_init(void)
591 acpi_status status = AE_OK;
592 struct acpi_buffer buffer = { sizeof(acpi_fadt), &acpi_fadt };
594 ACPI_FUNCTION_TRACE("acpi_early_init");
596 if (acpi_disabled)
597 return_VOID;
599 /* enable workarounds, unless strict ACPI spec. compliance */
600 if (!acpi_strict)
601 acpi_gbl_enable_interpreter_slack = TRUE;
603 status = acpi_initialize_subsystem();
604 if (ACPI_FAILURE(status)) {
605 printk(KERN_ERR PREFIX
606 "Unable to initialize the ACPI Interpreter\n");
607 goto error0;
610 status = acpi_load_tables();
611 if (ACPI_FAILURE(status)) {
612 printk(KERN_ERR PREFIX
613 "Unable to load the System Description Tables\n");
614 goto error0;
618 * Get a separate copy of the FADT for use by other drivers.
620 status = acpi_get_table(ACPI_TABLE_FADT, 1, &buffer);
621 if (ACPI_FAILURE(status)) {
622 printk(KERN_ERR PREFIX "Unable to get the FADT\n");
623 goto error0;
625 #ifdef CONFIG_X86
626 if (!acpi_ioapic) {
627 extern acpi_interrupt_flags acpi_sci_flags;
629 /* compatible (0) means level (3) */
630 if (acpi_sci_flags.trigger == 0)
631 acpi_sci_flags.trigger = 3;
633 /* Set PIC-mode SCI trigger type */
634 acpi_pic_sci_set_trigger(acpi_fadt.sci_int,
635 acpi_sci_flags.trigger);
636 } else {
637 extern int acpi_sci_override_gsi;
639 * now that acpi_fadt is initialized,
640 * update it with result from INT_SRC_OVR parsing
642 acpi_fadt.sci_int = acpi_sci_override_gsi;
644 #endif
646 status =
647 acpi_enable_subsystem(~
648 (ACPI_NO_HARDWARE_INIT |
649 ACPI_NO_ACPI_ENABLE));
650 if (ACPI_FAILURE(status)) {
651 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
652 goto error0;
655 return_VOID;
657 error0:
658 disable_acpi();
659 return_VOID;
662 static int __init acpi_bus_init(void)
664 int result = 0;
665 acpi_status status = AE_OK;
666 extern acpi_status acpi_os_initialize1(void);
668 ACPI_FUNCTION_TRACE("acpi_bus_init");
670 status = acpi_os_initialize1();
672 status =
673 acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
674 if (ACPI_FAILURE(status)) {
675 printk(KERN_ERR PREFIX
676 "Unable to start the ACPI Interpreter\n");
677 goto error1;
680 if (ACPI_FAILURE(status)) {
681 printk(KERN_ERR PREFIX
682 "Unable to initialize ACPI OS objects\n");
683 goto error1;
685 #ifdef CONFIG_ACPI_EC
687 * ACPI 2.0 requires the EC driver to be loaded and work before
688 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
689 * is called).
691 * This is accomplished by looking for the ECDT table, and getting
692 * the EC parameters out of that.
694 status = acpi_ec_ecdt_probe();
695 /* Ignore result. Not having an ECDT is not fatal. */
696 #endif
698 status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
699 if (ACPI_FAILURE(status)) {
700 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
701 goto error1;
704 printk(KERN_INFO PREFIX "Interpreter enabled\n");
707 * Get the system interrupt model and evaluate \_PIC.
709 result = acpi_bus_init_irq();
710 if (result)
711 goto error1;
714 * Register the for all standard device notifications.
716 status =
717 acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
718 &acpi_bus_notify, NULL);
719 if (ACPI_FAILURE(status)) {
720 printk(KERN_ERR PREFIX
721 "Unable to register for device notifications\n");
722 goto error1;
726 * Create the top ACPI proc directory
728 acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
730 return_VALUE(0);
732 /* Mimic structured exception handling */
733 error1:
734 acpi_terminate();
735 return_VALUE(-ENODEV);
738 decl_subsys(acpi, NULL, NULL);
740 static int __init acpi_init(void)
742 int result = 0;
744 ACPI_FUNCTION_TRACE("acpi_init");
746 printk(KERN_INFO PREFIX "Subsystem revision %08x\n", ACPI_CA_VERSION);
748 if (acpi_disabled) {
749 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
750 return_VALUE(-ENODEV);
753 firmware_register(&acpi_subsys);
755 result = acpi_bus_init();
757 if (!result) {
758 #ifdef CONFIG_PM_LEGACY
759 if (!PM_IS_ACTIVE())
760 pm_active = 1;
761 else {
762 printk(KERN_INFO PREFIX
763 "APM is already active, exiting\n");
764 disable_acpi();
765 result = -ENODEV;
767 #endif
768 } else
769 disable_acpi();
771 return_VALUE(result);
774 subsys_initcall(acpi_init);