Linux 2.6.19-rc1
[linux-2.6/next.git] / drivers / acpi / bus.c
blob279c4bac92e553aaec80c4dc1181f682852e2c41
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/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>
41 #define _COMPONENT ACPI_BUS_COMPONENT
42 ACPI_MODULE_NAME("acpi_bus")
43 #ifdef CONFIG_X86
44 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
45 #endif
47 struct fadt_descriptor acpi_fadt;
48 EXPORT_SYMBOL(acpi_fadt);
50 struct acpi_device *acpi_root;
51 struct proc_dir_entry *acpi_root_dir;
52 EXPORT_SYMBOL(acpi_root_dir);
54 #define STRUCT_TO_INT(s) (*((int*)&s))
56 /* --------------------------------------------------------------------------
57 Device Management
58 -------------------------------------------------------------------------- */
60 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
62 acpi_status status = AE_OK;
65 if (!device)
66 return -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_INFO, "No context for object [%p]\n",
73 handle));
74 return -ENODEV;
77 return 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;
88 if (!device)
89 return -EINVAL;
92 * Evaluate _STA if present.
94 if (device->flags.dynamic_status) {
95 status =
96 acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
97 if (ACPI_FAILURE(status))
98 return -ENODEV;
99 STRUCT_TO_INT(device->status) = (int)sta;
103 * Otherwise we assume the status of our parent (unless we don't
104 * have one, in which case status is implied).
106 else if (device->parent)
107 device->status = device->parent->status;
108 else
109 STRUCT_TO_INT(device->status) = 0x0F;
111 if (device->status.functional && !device->status.present) {
112 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
113 "functional but not present; setting present\n",
114 device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
115 device->status.present = 1;
118 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
119 device->pnp.bus_id,
120 (u32) STRUCT_TO_INT(device->status)));
122 return 0;
125 EXPORT_SYMBOL(acpi_bus_get_status);
127 /* --------------------------------------------------------------------------
128 Power Management
129 -------------------------------------------------------------------------- */
131 int acpi_bus_get_power(acpi_handle handle, int *state)
133 int result = 0;
134 acpi_status status = 0;
135 struct acpi_device *device = NULL;
136 unsigned long psc = 0;
139 result = acpi_bus_get_device(handle, &device);
140 if (result)
141 return result;
143 *state = ACPI_STATE_UNKNOWN;
145 if (!device->flags.power_manageable) {
146 /* TBD: Non-recursive algorithm for walking up hierarchy */
147 if (device->parent)
148 *state = device->parent->power.state;
149 else
150 *state = ACPI_STATE_D0;
151 } else {
153 * Get the device's power state either directly (via _PSC) or
154 * indirectly (via power resources).
156 if (device->power.flags.explicit_get) {
157 status = acpi_evaluate_integer(device->handle, "_PSC",
158 NULL, &psc);
159 if (ACPI_FAILURE(status))
160 return -ENODEV;
161 device->power.state = (int)psc;
162 } else if (device->power.flags.power_resources) {
163 result = acpi_power_get_inferred_state(device);
164 if (result)
165 return result;
168 *state = device->power.state;
171 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
172 device->pnp.bus_id, device->power.state));
174 return 0;
177 EXPORT_SYMBOL(acpi_bus_get_power);
179 int acpi_bus_set_power(acpi_handle handle, int state)
181 int result = 0;
182 acpi_status status = AE_OK;
183 struct acpi_device *device = NULL;
184 char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
187 result = acpi_bus_get_device(handle, &device);
188 if (result)
189 return result;
191 if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
192 return -EINVAL;
194 /* Make sure this is a valid target state */
196 if (!device->flags.power_manageable) {
197 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
198 device->kobj.name));
199 return -ENODEV;
202 * Get device's current power state if it's unknown
203 * This means device power state isn't initialized or previous setting failed
205 if (!device->flags.force_power_state) {
206 if (device->power.state == ACPI_STATE_UNKNOWN)
207 acpi_bus_get_power(device->handle, &device->power.state);
208 if (state == device->power.state) {
209 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
210 state));
211 return 0;
214 if (!device->power.states[state].flags.valid) {
215 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
216 return -ENODEV;
218 if (device->parent && (state < device->parent->power.state)) {
219 printk(KERN_WARNING PREFIX
220 "Cannot set device to a higher-powered"
221 " state than parent\n");
222 return -ENODEV;
226 * Transition Power
227 * ----------------
228 * On transitions to a high-powered state we first apply power (via
229 * power resources) then evalute _PSx. Conversly for transitions to
230 * a lower-powered state.
232 if (state < device->power.state) {
233 if (device->power.flags.power_resources) {
234 result = acpi_power_transition(device, state);
235 if (result)
236 goto end;
238 if (device->power.states[state].flags.explicit_set) {
239 status = acpi_evaluate_object(device->handle,
240 object_name, NULL, NULL);
241 if (ACPI_FAILURE(status)) {
242 result = -ENODEV;
243 goto end;
246 } else {
247 if (device->power.states[state].flags.explicit_set) {
248 status = acpi_evaluate_object(device->handle,
249 object_name, NULL, NULL);
250 if (ACPI_FAILURE(status)) {
251 result = -ENODEV;
252 goto end;
255 if (device->power.flags.power_resources) {
256 result = acpi_power_transition(device, state);
257 if (result)
258 goto end;
262 end:
263 if (result)
264 printk(KERN_WARNING PREFIX
265 "Transitioning device [%s] to D%d\n",
266 device->pnp.bus_id, state);
267 else
268 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
269 "Device [%s] transitioned to D%d\n",
270 device->pnp.bus_id, state));
272 return result;
275 EXPORT_SYMBOL(acpi_bus_set_power);
277 /* --------------------------------------------------------------------------
278 Event Management
279 -------------------------------------------------------------------------- */
281 static DEFINE_SPINLOCK(acpi_bus_event_lock);
283 LIST_HEAD(acpi_bus_event_list);
284 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
286 extern int event_is_open;
288 int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
290 struct acpi_bus_event *event = NULL;
291 unsigned long flags = 0;
294 if (!device)
295 return -EINVAL;
297 /* drop event on the floor if no one's listening */
298 if (!event_is_open)
299 return 0;
301 event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
302 if (!event)
303 return -ENOMEM;
305 strcpy(event->device_class, device->pnp.device_class);
306 strcpy(event->bus_id, device->pnp.bus_id);
307 event->type = type;
308 event->data = data;
310 spin_lock_irqsave(&acpi_bus_event_lock, flags);
311 list_add_tail(&event->node, &acpi_bus_event_list);
312 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
314 wake_up_interruptible(&acpi_bus_event_queue);
316 return 0;
319 EXPORT_SYMBOL(acpi_bus_generate_event);
321 int acpi_bus_receive_event(struct acpi_bus_event *event)
323 unsigned long flags = 0;
324 struct acpi_bus_event *entry = NULL;
326 DECLARE_WAITQUEUE(wait, current);
329 if (!event)
330 return -EINVAL;
332 if (list_empty(&acpi_bus_event_list)) {
334 set_current_state(TASK_INTERRUPTIBLE);
335 add_wait_queue(&acpi_bus_event_queue, &wait);
337 if (list_empty(&acpi_bus_event_list))
338 schedule();
340 remove_wait_queue(&acpi_bus_event_queue, &wait);
341 set_current_state(TASK_RUNNING);
343 if (signal_pending(current))
344 return -ERESTARTSYS;
347 spin_lock_irqsave(&acpi_bus_event_lock, flags);
348 entry =
349 list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
350 if (entry)
351 list_del(&entry->node);
352 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
354 if (!entry)
355 return -ENODEV;
357 memcpy(event, entry, sizeof(struct acpi_bus_event));
359 kfree(entry);
361 return 0;
364 EXPORT_SYMBOL(acpi_bus_receive_event);
366 /* --------------------------------------------------------------------------
367 Notification Handling
368 -------------------------------------------------------------------------- */
370 static int
371 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
373 acpi_status status = 0;
374 struct acpi_device_status old_status;
377 if (!device)
378 return -EINVAL;
380 if (status_changed)
381 *status_changed = 0;
383 old_status = device->status;
386 * Make sure this device's parent is present before we go about
387 * messing with the device.
389 if (device->parent && !device->parent->status.present) {
390 device->status = device->parent->status;
391 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
392 if (status_changed)
393 *status_changed = 1;
395 return 0;
398 status = acpi_bus_get_status(device);
399 if (ACPI_FAILURE(status))
400 return -ENODEV;
402 if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
403 return 0;
405 if (status_changed)
406 *status_changed = 1;
409 * Device Insertion/Removal
411 if ((device->status.present) && !(old_status.present)) {
412 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
413 /* TBD: Handle device insertion */
414 } else if (!(device->status.present) && (old_status.present)) {
415 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
416 /* TBD: Handle device removal */
419 return 0;
422 static int acpi_bus_check_scope(struct acpi_device *device)
424 int result = 0;
425 int status_changed = 0;
428 if (!device)
429 return -EINVAL;
431 /* Status Change? */
432 result = acpi_bus_check_device(device, &status_changed);
433 if (result)
434 return result;
436 if (!status_changed)
437 return 0;
440 * TBD: Enumerate child devices within this device's scope and
441 * run acpi_bus_check_device()'s on them.
444 return 0;
448 * acpi_bus_notify
449 * ---------------
450 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
452 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
454 int result = 0;
455 struct acpi_device *device = NULL;
458 if (acpi_bus_get_device(handle, &device))
459 return;
461 switch (type) {
463 case ACPI_NOTIFY_BUS_CHECK:
464 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
465 "Received BUS CHECK notification for device [%s]\n",
466 device->pnp.bus_id));
467 result = acpi_bus_check_scope(device);
469 * TBD: We'll need to outsource certain events to non-ACPI
470 * drivers via the device manager (device.c).
472 break;
474 case ACPI_NOTIFY_DEVICE_CHECK:
475 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
476 "Received DEVICE CHECK notification for device [%s]\n",
477 device->pnp.bus_id));
478 result = acpi_bus_check_device(device, NULL);
480 * TBD: We'll need to outsource certain events to non-ACPI
481 * drivers via the device manager (device.c).
483 break;
485 case ACPI_NOTIFY_DEVICE_WAKE:
486 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
487 "Received DEVICE WAKE notification for device [%s]\n",
488 device->pnp.bus_id));
489 /* TBD */
490 break;
492 case ACPI_NOTIFY_EJECT_REQUEST:
493 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
494 "Received EJECT REQUEST notification for device [%s]\n",
495 device->pnp.bus_id));
496 /* TBD */
497 break;
499 case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
500 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
501 "Received DEVICE CHECK LIGHT notification for device [%s]\n",
502 device->pnp.bus_id));
503 /* TBD: Exactly what does 'light' mean? */
504 break;
506 case ACPI_NOTIFY_FREQUENCY_MISMATCH:
507 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
508 "Received FREQUENCY MISMATCH notification for device [%s]\n",
509 device->pnp.bus_id));
510 /* TBD */
511 break;
513 case ACPI_NOTIFY_BUS_MODE_MISMATCH:
514 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
515 "Received BUS MODE MISMATCH notification for device [%s]\n",
516 device->pnp.bus_id));
517 /* TBD */
518 break;
520 case ACPI_NOTIFY_POWER_FAULT:
521 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
522 "Received POWER FAULT notification for device [%s]\n",
523 device->pnp.bus_id));
524 /* TBD */
525 break;
527 default:
528 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
529 "Received unknown/unsupported notification [%08x]\n",
530 type));
531 break;
534 return;
537 /* --------------------------------------------------------------------------
538 Initialization/Cleanup
539 -------------------------------------------------------------------------- */
541 static int __init acpi_bus_init_irq(void)
543 acpi_status status = AE_OK;
544 union acpi_object arg = { ACPI_TYPE_INTEGER };
545 struct acpi_object_list arg_list = { 1, &arg };
546 char *message = NULL;
550 * Let the system know what interrupt model we are using by
551 * evaluating the \_PIC object, if exists.
554 switch (acpi_irq_model) {
555 case ACPI_IRQ_MODEL_PIC:
556 message = "PIC";
557 break;
558 case ACPI_IRQ_MODEL_IOAPIC:
559 message = "IOAPIC";
560 break;
561 case ACPI_IRQ_MODEL_IOSAPIC:
562 message = "IOSAPIC";
563 break;
564 default:
565 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
566 return -ENODEV;
569 printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
571 arg.integer.value = acpi_irq_model;
573 status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
574 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
575 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
576 return -ENODEV;
579 return 0;
582 void __init acpi_early_init(void)
584 acpi_status status = AE_OK;
585 struct acpi_buffer buffer = { sizeof(acpi_fadt), &acpi_fadt };
588 if (acpi_disabled)
589 return;
591 printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
593 /* enable workarounds, unless strict ACPI spec. compliance */
594 if (!acpi_strict)
595 acpi_gbl_enable_interpreter_slack = TRUE;
597 status = acpi_initialize_subsystem();
598 if (ACPI_FAILURE(status)) {
599 printk(KERN_ERR PREFIX
600 "Unable to initialize the ACPI Interpreter\n");
601 goto error0;
604 status = acpi_load_tables();
605 if (ACPI_FAILURE(status)) {
606 printk(KERN_ERR PREFIX
607 "Unable to load the System Description Tables\n");
608 goto error0;
612 * Get a separate copy of the FADT for use by other drivers.
614 status = acpi_get_table(ACPI_TABLE_ID_FADT, 1, &buffer);
615 if (ACPI_FAILURE(status)) {
616 printk(KERN_ERR PREFIX "Unable to get the FADT\n");
617 goto error0;
619 #ifdef CONFIG_X86
620 if (!acpi_ioapic) {
621 extern acpi_interrupt_flags acpi_sci_flags;
623 /* compatible (0) means level (3) */
624 if (acpi_sci_flags.trigger == 0)
625 acpi_sci_flags.trigger = 3;
627 /* Set PIC-mode SCI trigger type */
628 acpi_pic_sci_set_trigger(acpi_fadt.sci_int,
629 acpi_sci_flags.trigger);
630 } else {
631 extern int acpi_sci_override_gsi;
633 * now that acpi_fadt is initialized,
634 * update it with result from INT_SRC_OVR parsing
636 acpi_fadt.sci_int = acpi_sci_override_gsi;
638 #endif
640 status =
641 acpi_enable_subsystem(~
642 (ACPI_NO_HARDWARE_INIT |
643 ACPI_NO_ACPI_ENABLE));
644 if (ACPI_FAILURE(status)) {
645 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
646 goto error0;
649 return;
651 error0:
652 disable_acpi();
653 return;
656 static int __init acpi_bus_init(void)
658 int result = 0;
659 acpi_status status = AE_OK;
660 extern acpi_status acpi_os_initialize1(void);
663 status = acpi_os_initialize1();
665 status =
666 acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
667 if (ACPI_FAILURE(status)) {
668 printk(KERN_ERR PREFIX
669 "Unable to start the ACPI Interpreter\n");
670 goto error1;
673 if (ACPI_FAILURE(status)) {
674 printk(KERN_ERR PREFIX
675 "Unable to initialize ACPI OS objects\n");
676 goto error1;
678 #ifdef CONFIG_ACPI_EC
680 * ACPI 2.0 requires the EC driver to be loaded and work before
681 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
682 * is called).
684 * This is accomplished by looking for the ECDT table, and getting
685 * the EC parameters out of that.
687 status = acpi_ec_ecdt_probe();
688 /* Ignore result. Not having an ECDT is not fatal. */
689 #endif
691 status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
692 if (ACPI_FAILURE(status)) {
693 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
694 goto error1;
697 printk(KERN_INFO PREFIX "Interpreter enabled\n");
700 * Get the system interrupt model and evaluate \_PIC.
702 result = acpi_bus_init_irq();
703 if (result)
704 goto error1;
707 * Register the for all standard device notifications.
709 status =
710 acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
711 &acpi_bus_notify, NULL);
712 if (ACPI_FAILURE(status)) {
713 printk(KERN_ERR PREFIX
714 "Unable to register for device notifications\n");
715 goto error1;
719 * Create the top ACPI proc directory
721 acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
723 return 0;
725 /* Mimic structured exception handling */
726 error1:
727 acpi_terminate();
728 return -ENODEV;
731 decl_subsys(acpi, NULL, NULL);
733 static int __init acpi_init(void)
735 int result = 0;
738 if (acpi_disabled) {
739 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
740 return -ENODEV;
743 result = firmware_register(&acpi_subsys);
744 if (result < 0)
745 printk(KERN_WARNING "%s: firmware_register error: %d\n",
746 __FUNCTION__, result);
748 result = acpi_bus_init();
750 if (!result) {
751 #ifdef CONFIG_PM_LEGACY
752 if (!PM_IS_ACTIVE())
753 pm_active = 1;
754 else {
755 printk(KERN_INFO PREFIX
756 "APM is already active, exiting\n");
757 disable_acpi();
758 result = -ENODEV;
760 #endif
761 } else
762 disable_acpi();
764 return result;
767 subsys_initcall(acpi_init);