Author: Ralf Baechle <ralf@linux-mips.org>
[linux-2.6/mini2440.git] / drivers / acpi / bus.c
blobfb2cff9a2d24679cf99e9c82b9f04a4e32ea4bb0
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("bus");
43 #ifdef CONFIG_X86
44 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
45 #endif
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 /* --------------------------------------------------------------------------
54 Device Management
55 -------------------------------------------------------------------------- */
57 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
59 acpi_status status = AE_OK;
62 if (!device)
63 return -EINVAL;
65 /* TBD: Support fixed-feature devices */
67 status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
68 if (ACPI_FAILURE(status) || !*device) {
69 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
70 handle));
71 return -ENODEV;
74 return 0;
77 EXPORT_SYMBOL(acpi_bus_get_device);
79 int acpi_bus_get_status(struct acpi_device *device)
81 acpi_status status = AE_OK;
82 unsigned long sta = 0;
85 if (!device)
86 return -EINVAL;
89 * Evaluate _STA if present.
91 if (device->flags.dynamic_status) {
92 status =
93 acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
94 if (ACPI_FAILURE(status))
95 return -ENODEV;
96 STRUCT_TO_INT(device->status) = (int)sta;
100 * Otherwise we assume the status of our parent (unless we don't
101 * have one, in which case status is implied).
103 else if (device->parent)
104 device->status = device->parent->status;
105 else
106 STRUCT_TO_INT(device->status) =
107 ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
108 ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
110 if (device->status.functional && !device->status.present) {
111 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
112 "functional but not present; setting present\n",
113 device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
114 device->status.present = 1;
117 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
118 device->pnp.bus_id,
119 (u32) STRUCT_TO_INT(device->status)));
121 return 0;
124 EXPORT_SYMBOL(acpi_bus_get_status);
126 /* --------------------------------------------------------------------------
127 Power Management
128 -------------------------------------------------------------------------- */
130 int acpi_bus_get_power(acpi_handle handle, int *state)
132 int result = 0;
133 acpi_status status = 0;
134 struct acpi_device *device = NULL;
135 unsigned long psc = 0;
138 result = acpi_bus_get_device(handle, &device);
139 if (result)
140 return result;
142 *state = ACPI_STATE_UNKNOWN;
144 if (!device->flags.power_manageable) {
145 /* TBD: Non-recursive algorithm for walking up hierarchy */
146 if (device->parent)
147 *state = device->parent->power.state;
148 else
149 *state = ACPI_STATE_D0;
150 } else {
152 * Get the device's power state either directly (via _PSC) or
153 * indirectly (via power resources).
155 if (device->power.flags.explicit_get) {
156 status = acpi_evaluate_integer(device->handle, "_PSC",
157 NULL, &psc);
158 if (ACPI_FAILURE(status))
159 return -ENODEV;
160 device->power.state = (int)psc;
161 } else if (device->power.flags.power_resources) {
162 result = acpi_power_get_inferred_state(device);
163 if (result)
164 return result;
167 *state = device->power.state;
170 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
171 device->pnp.bus_id, device->power.state));
173 return 0;
176 EXPORT_SYMBOL(acpi_bus_get_power);
178 int acpi_bus_set_power(acpi_handle handle, int state)
180 int result = 0;
181 acpi_status status = AE_OK;
182 struct acpi_device *device = NULL;
183 char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
186 result = acpi_bus_get_device(handle, &device);
187 if (result)
188 return result;
190 if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
191 return -EINVAL;
193 /* Make sure this is a valid target state */
195 if (!device->flags.power_manageable) {
196 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
197 kobject_name(&device->dev.kobj)));
198 return -ENODEV;
201 * Get device's current power state if it's unknown
202 * This means device power state isn't initialized or previous setting failed
204 if ((device->power.state == ACPI_STATE_UNKNOWN) || device->flags.force_power_state)
205 acpi_bus_get_power(device->handle, &device->power.state);
206 if ((state == device->power.state) && !device->flags.force_power_state) {
207 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
208 state));
209 return 0;
212 if (!device->power.states[state].flags.valid) {
213 printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
214 return -ENODEV;
216 if (device->parent && (state < device->parent->power.state)) {
217 printk(KERN_WARNING PREFIX
218 "Cannot set device to a higher-powered"
219 " state than parent\n");
220 return -ENODEV;
224 * Transition Power
225 * ----------------
226 * On transitions to a high-powered state we first apply power (via
227 * power resources) then evalute _PSx. Conversly for transitions to
228 * a lower-powered state.
230 if (state < device->power.state) {
231 if (device->power.flags.power_resources) {
232 result = acpi_power_transition(device, state);
233 if (result)
234 goto end;
236 if (device->power.states[state].flags.explicit_set) {
237 status = acpi_evaluate_object(device->handle,
238 object_name, NULL, NULL);
239 if (ACPI_FAILURE(status)) {
240 result = -ENODEV;
241 goto end;
244 } else {
245 if (device->power.states[state].flags.explicit_set) {
246 status = acpi_evaluate_object(device->handle,
247 object_name, NULL, NULL);
248 if (ACPI_FAILURE(status)) {
249 result = -ENODEV;
250 goto end;
253 if (device->power.flags.power_resources) {
254 result = acpi_power_transition(device, state);
255 if (result)
256 goto end;
260 end:
261 if (result)
262 printk(KERN_WARNING PREFIX
263 "Transitioning device [%s] to D%d\n",
264 device->pnp.bus_id, state);
265 else {
266 device->power.state = state;
267 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
268 "Device [%s] transitioned to D%d\n",
269 device->pnp.bus_id, state));
272 return result;
275 EXPORT_SYMBOL(acpi_bus_set_power);
277 /* --------------------------------------------------------------------------
278 Event Management
279 -------------------------------------------------------------------------- */
281 #ifdef CONFIG_ACPI_PROC_EVENT
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_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
291 struct acpi_bus_event *event;
292 unsigned long flags = 0;
294 /* drop event on the floor if no one's listening */
295 if (!event_is_open)
296 return 0;
298 event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
299 if (!event)
300 return -ENOMEM;
302 strcpy(event->device_class, device_class);
303 strcpy(event->bus_id, bus_id);
304 event->type = type;
305 event->data = data;
307 spin_lock_irqsave(&acpi_bus_event_lock, flags);
308 list_add_tail(&event->node, &acpi_bus_event_list);
309 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
311 wake_up_interruptible(&acpi_bus_event_queue);
313 return 0;
317 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
319 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
321 if (!device)
322 return -EINVAL;
323 return acpi_bus_generate_proc_event4(device->pnp.device_class,
324 device->pnp.bus_id, type, data);
327 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
329 int acpi_bus_receive_event(struct acpi_bus_event *event)
331 unsigned long flags = 0;
332 struct acpi_bus_event *entry = NULL;
334 DECLARE_WAITQUEUE(wait, current);
337 if (!event)
338 return -EINVAL;
340 if (list_empty(&acpi_bus_event_list)) {
342 set_current_state(TASK_INTERRUPTIBLE);
343 add_wait_queue(&acpi_bus_event_queue, &wait);
345 if (list_empty(&acpi_bus_event_list))
346 schedule();
348 remove_wait_queue(&acpi_bus_event_queue, &wait);
349 set_current_state(TASK_RUNNING);
351 if (signal_pending(current))
352 return -ERESTARTSYS;
355 spin_lock_irqsave(&acpi_bus_event_lock, flags);
356 entry =
357 list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
358 if (entry)
359 list_del(&entry->node);
360 spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
362 if (!entry)
363 return -ENODEV;
365 memcpy(event, entry, sizeof(struct acpi_bus_event));
367 kfree(entry);
369 return 0;
372 EXPORT_SYMBOL(acpi_bus_receive_event);
373 #endif /* CONFIG_ACPI_PROC_EVENT */
375 /* --------------------------------------------------------------------------
376 Notification Handling
377 -------------------------------------------------------------------------- */
379 static int
380 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
382 acpi_status status = 0;
383 struct acpi_device_status old_status;
386 if (!device)
387 return -EINVAL;
389 if (status_changed)
390 *status_changed = 0;
392 old_status = device->status;
395 * Make sure this device's parent is present before we go about
396 * messing with the device.
398 if (device->parent && !device->parent->status.present) {
399 device->status = device->parent->status;
400 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
401 if (status_changed)
402 *status_changed = 1;
404 return 0;
407 status = acpi_bus_get_status(device);
408 if (ACPI_FAILURE(status))
409 return -ENODEV;
411 if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
412 return 0;
414 if (status_changed)
415 *status_changed = 1;
418 * Device Insertion/Removal
420 if ((device->status.present) && !(old_status.present)) {
421 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
422 /* TBD: Handle device insertion */
423 } else if (!(device->status.present) && (old_status.present)) {
424 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
425 /* TBD: Handle device removal */
428 return 0;
431 static int acpi_bus_check_scope(struct acpi_device *device)
433 int result = 0;
434 int status_changed = 0;
437 if (!device)
438 return -EINVAL;
440 /* Status Change? */
441 result = acpi_bus_check_device(device, &status_changed);
442 if (result)
443 return result;
445 if (!status_changed)
446 return 0;
449 * TBD: Enumerate child devices within this device's scope and
450 * run acpi_bus_check_device()'s on them.
453 return 0;
457 * acpi_bus_notify
458 * ---------------
459 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
461 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
463 int result = 0;
464 struct acpi_device *device = NULL;
467 if (acpi_bus_get_device(handle, &device))
468 return;
470 switch (type) {
472 case ACPI_NOTIFY_BUS_CHECK:
473 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
474 "Received BUS CHECK notification for device [%s]\n",
475 device->pnp.bus_id));
476 result = acpi_bus_check_scope(device);
478 * TBD: We'll need to outsource certain events to non-ACPI
479 * drivers via the device manager (device.c).
481 break;
483 case ACPI_NOTIFY_DEVICE_CHECK:
484 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
485 "Received DEVICE CHECK notification for device [%s]\n",
486 device->pnp.bus_id));
487 result = acpi_bus_check_device(device, NULL);
489 * TBD: We'll need to outsource certain events to non-ACPI
490 * drivers via the device manager (device.c).
492 break;
494 case ACPI_NOTIFY_DEVICE_WAKE:
495 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
496 "Received DEVICE WAKE notification for device [%s]\n",
497 device->pnp.bus_id));
498 /* TBD */
499 break;
501 case ACPI_NOTIFY_EJECT_REQUEST:
502 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
503 "Received EJECT REQUEST notification for device [%s]\n",
504 device->pnp.bus_id));
505 /* TBD */
506 break;
508 case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
509 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
510 "Received DEVICE CHECK LIGHT notification for device [%s]\n",
511 device->pnp.bus_id));
512 /* TBD: Exactly what does 'light' mean? */
513 break;
515 case ACPI_NOTIFY_FREQUENCY_MISMATCH:
516 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
517 "Received FREQUENCY MISMATCH notification for device [%s]\n",
518 device->pnp.bus_id));
519 /* TBD */
520 break;
522 case ACPI_NOTIFY_BUS_MODE_MISMATCH:
523 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
524 "Received BUS MODE MISMATCH notification for device [%s]\n",
525 device->pnp.bus_id));
526 /* TBD */
527 break;
529 case ACPI_NOTIFY_POWER_FAULT:
530 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
531 "Received POWER FAULT notification for device [%s]\n",
532 device->pnp.bus_id));
533 /* TBD */
534 break;
536 default:
537 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
538 "Received unknown/unsupported notification [%08x]\n",
539 type));
540 break;
543 return;
546 /* --------------------------------------------------------------------------
547 Initialization/Cleanup
548 -------------------------------------------------------------------------- */
550 static int __init acpi_bus_init_irq(void)
552 acpi_status status = AE_OK;
553 union acpi_object arg = { ACPI_TYPE_INTEGER };
554 struct acpi_object_list arg_list = { 1, &arg };
555 char *message = NULL;
559 * Let the system know what interrupt model we are using by
560 * evaluating the \_PIC object, if exists.
563 switch (acpi_irq_model) {
564 case ACPI_IRQ_MODEL_PIC:
565 message = "PIC";
566 break;
567 case ACPI_IRQ_MODEL_IOAPIC:
568 message = "IOAPIC";
569 break;
570 case ACPI_IRQ_MODEL_IOSAPIC:
571 message = "IOSAPIC";
572 break;
573 case ACPI_IRQ_MODEL_PLATFORM:
574 message = "platform specific model";
575 break;
576 default:
577 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
578 return -ENODEV;
581 printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
583 arg.integer.value = acpi_irq_model;
585 status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
586 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
587 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
588 return -ENODEV;
591 return 0;
594 acpi_native_uint acpi_gbl_permanent_mmap;
597 void __init acpi_early_init(void)
599 acpi_status status = AE_OK;
601 if (acpi_disabled)
602 return;
604 printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
606 /* enable workarounds, unless strict ACPI spec. compliance */
607 if (!acpi_strict)
608 acpi_gbl_enable_interpreter_slack = TRUE;
610 acpi_gbl_permanent_mmap = 1;
612 status = acpi_reallocate_root_table();
613 if (ACPI_FAILURE(status)) {
614 printk(KERN_ERR PREFIX
615 "Unable to reallocate ACPI tables\n");
616 goto error0;
619 status = acpi_initialize_subsystem();
620 if (ACPI_FAILURE(status)) {
621 printk(KERN_ERR PREFIX
622 "Unable to initialize the ACPI Interpreter\n");
623 goto error0;
626 status = acpi_load_tables();
627 if (ACPI_FAILURE(status)) {
628 printk(KERN_ERR PREFIX
629 "Unable to load the System Description Tables\n");
630 goto error0;
633 #ifdef CONFIG_X86
634 if (!acpi_ioapic) {
635 extern u8 acpi_sci_flags;
637 /* compatible (0) means level (3) */
638 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
639 acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
640 acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
642 /* Set PIC-mode SCI trigger type */
643 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
644 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
645 } else {
646 extern int acpi_sci_override_gsi;
648 * now that acpi_gbl_FADT is initialized,
649 * update it with result from INT_SRC_OVR parsing
651 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
653 #endif
655 status =
656 acpi_enable_subsystem(~
657 (ACPI_NO_HARDWARE_INIT |
658 ACPI_NO_ACPI_ENABLE));
659 if (ACPI_FAILURE(status)) {
660 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
661 goto error0;
664 return;
666 error0:
667 disable_acpi();
668 return;
671 static int __init acpi_bus_init(void)
673 int result = 0;
674 acpi_status status = AE_OK;
675 extern acpi_status acpi_os_initialize1(void);
678 status = acpi_os_initialize1();
680 status =
681 acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
682 if (ACPI_FAILURE(status)) {
683 printk(KERN_ERR PREFIX
684 "Unable to start the ACPI Interpreter\n");
685 goto error1;
688 if (ACPI_FAILURE(status)) {
689 printk(KERN_ERR PREFIX
690 "Unable to initialize ACPI OS objects\n");
691 goto error1;
693 #ifdef CONFIG_ACPI_EC
695 * ACPI 2.0 requires the EC driver to be loaded and work before
696 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
697 * is called).
699 * This is accomplished by looking for the ECDT table, and getting
700 * the EC parameters out of that.
702 status = acpi_ec_ecdt_probe();
703 /* Ignore result. Not having an ECDT is not fatal. */
704 #endif
706 status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
707 if (ACPI_FAILURE(status)) {
708 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
709 goto error1;
712 printk(KERN_INFO PREFIX "Interpreter enabled\n");
714 /* Initialize sleep structures */
715 acpi_sleep_init();
718 * Get the system interrupt model and evaluate \_PIC.
720 result = acpi_bus_init_irq();
721 if (result)
722 goto error1;
725 * Register the for all standard device notifications.
727 status =
728 acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
729 &acpi_bus_notify, NULL);
730 if (ACPI_FAILURE(status)) {
731 printk(KERN_ERR PREFIX
732 "Unable to register for device notifications\n");
733 goto error1;
737 * Create the top ACPI proc directory
739 acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
741 return 0;
743 /* Mimic structured exception handling */
744 error1:
745 acpi_terminate();
746 return -ENODEV;
749 decl_subsys(acpi, NULL, NULL);
751 static int __init acpi_init(void)
753 int result = 0;
756 if (acpi_disabled) {
757 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
758 return -ENODEV;
761 result = firmware_register(&acpi_subsys);
762 if (result < 0)
763 printk(KERN_WARNING "%s: firmware_register error: %d\n",
764 __FUNCTION__, result);
766 result = acpi_bus_init();
768 if (!result) {
769 #ifdef CONFIG_PM_LEGACY
770 if (!PM_IS_ACTIVE())
771 pm_active = 1;
772 else {
773 printk(KERN_INFO PREFIX
774 "APM is already active, exiting\n");
775 disable_acpi();
776 result = -ENODEV;
778 #endif
779 } else
780 disable_acpi();
782 return result;
785 subsys_initcall(acpi_init);