bus.c revision 7daef60721e03809c7e5f8aa8491df4190f6b56f 
1/*
2 *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
3 *
4 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5 *
6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7 *
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.
12 *
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.
17 *
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.
21 *
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 */
24
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>
40
41#define _COMPONENT		ACPI_BUS_COMPONENT
42ACPI_MODULE_NAME("acpi_bus")
43#ifdef	CONFIG_X86
44extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
45#endif
46
47struct fadt_descriptor acpi_fadt;
48EXPORT_SYMBOL(acpi_fadt);
49
50struct acpi_device *acpi_root;
51struct proc_dir_entry *acpi_root_dir;
52EXPORT_SYMBOL(acpi_root_dir);
53
54#define STRUCT_TO_INT(s)	(*((int*)&s))
55
56/* --------------------------------------------------------------------------
57                                Device Management
58   -------------------------------------------------------------------------- */
59
60int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
61{
62	acpi_status status = AE_OK;
63
64
65	if (!device)
66		return -EINVAL;
67
68	/* TBD: Support fixed-feature devices */
69
70	status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
71	if (ACPI_FAILURE(status) || !*device) {
72		ACPI_EXCEPTION((AE_INFO, status, "No context for object [%p]", handle));
73		return -ENODEV;
74	}
75
76	return 0;
77}
78
79EXPORT_SYMBOL(acpi_bus_get_device);
80
81int acpi_bus_get_status(struct acpi_device *device)
82{
83	acpi_status status = AE_OK;
84	unsigned long sta = 0;
85
86
87	if (!device)
88		return -EINVAL;
89
90	/*
91	 * Evaluate _STA if present.
92	 */
93	if (device->flags.dynamic_status) {
94		status =
95		    acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
96		if (ACPI_FAILURE(status))
97			return -ENODEV;
98		STRUCT_TO_INT(device->status) = (int)sta;
99	}
100
101	/*
102	 * Otherwise we assume the status of our parent (unless we don't
103	 * have one, in which case status is implied).
104	 */
105	else if (device->parent)
106		device->status = device->parent->status;
107	else
108		STRUCT_TO_INT(device->status) = 0x0F;
109
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;
115	}
116
117	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
118			  device->pnp.bus_id,
119			  (u32) STRUCT_TO_INT(device->status)));
120
121	return 0;
122}
123
124EXPORT_SYMBOL(acpi_bus_get_status);
125
126/* --------------------------------------------------------------------------
127                                 Power Management
128   -------------------------------------------------------------------------- */
129
130int acpi_bus_get_power(acpi_handle handle, int *state)
131{
132	int result = 0;
133	acpi_status status = 0;
134	struct acpi_device *device = NULL;
135	unsigned long psc = 0;
136
137
138	result = acpi_bus_get_device(handle, &device);
139	if (result)
140		return result;
141
142	*state = ACPI_STATE_UNKNOWN;
143
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 {
151		/*
152		 * Get the device's power state either directly (via _PSC) or
153		 * indirectly (via power resources).
154		 */
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;
165		}
166
167		*state = device->power.state;
168	}
169
170	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
171			  device->pnp.bus_id, device->power.state));
172
173	return 0;
174}
175
176EXPORT_SYMBOL(acpi_bus_get_power);
177
178int acpi_bus_set_power(acpi_handle handle, int state)
179{
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' };
184
185
186	result = acpi_bus_get_device(handle, &device);
187	if (result)
188		return result;
189
190	if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
191		return -EINVAL;
192
193	/* Make sure this is a valid target state */
194
195	if (!device->flags.power_manageable) {
196		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable",
197				device->kobj.name));
198		return -ENODEV;
199	}
200	/*
201	 * Get device's current power state if it's unknown
202	 * This means device power state isn't initialized or previous setting failed
203	 */
204	if (!device->flags.force_power_state) {
205		if (device->power.state == ACPI_STATE_UNKNOWN)
206			acpi_bus_get_power(device->handle, &device->power.state);
207		if (state == device->power.state) {
208			ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
209					  state));
210			return 0;
211		}
212	}
213	if (!device->power.states[state].flags.valid) {
214		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
215		return -ENODEV;
216	}
217	if (device->parent && (state < device->parent->power.state)) {
218		printk(KERN_WARNING PREFIX
219			      "Cannot set device to a higher-powered"
220			      " state than parent\n");
221		return -ENODEV;
222	}
223
224	/*
225	 * Transition Power
226	 * ----------------
227	 * On transitions to a high-powered state we first apply power (via
228	 * power resources) then evalute _PSx.  Conversly for transitions to
229	 * a lower-powered state.
230	 */
231	if (state < device->power.state) {
232		if (device->power.flags.power_resources) {
233			result = acpi_power_transition(device, state);
234			if (result)
235				goto end;
236		}
237		if (device->power.states[state].flags.explicit_set) {
238			status = acpi_evaluate_object(device->handle,
239						      object_name, NULL, NULL);
240			if (ACPI_FAILURE(status)) {
241				result = -ENODEV;
242				goto end;
243			}
244		}
245	} else {
246		if (device->power.states[state].flags.explicit_set) {
247			status = acpi_evaluate_object(device->handle,
248						      object_name, NULL, NULL);
249			if (ACPI_FAILURE(status)) {
250				result = -ENODEV;
251				goto end;
252			}
253		}
254		if (device->power.flags.power_resources) {
255			result = acpi_power_transition(device, state);
256			if (result)
257				goto end;
258		}
259	}
260
261      end:
262	if (result)
263		printk(KERN_WARNING PREFIX
264			      "Transitioning device [%s] to D%d\n",
265			      device->pnp.bus_id, state);
266	else
267		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
268				  "Device [%s] transitioned to D%d\n",
269				  device->pnp.bus_id, state));
270
271	return result;
272}
273
274EXPORT_SYMBOL(acpi_bus_set_power);
275
276/* --------------------------------------------------------------------------
277                                Event Management
278   -------------------------------------------------------------------------- */
279
280static DEFINE_SPINLOCK(acpi_bus_event_lock);
281
282LIST_HEAD(acpi_bus_event_list);
283DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
284
285extern int event_is_open;
286
287int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
288{
289	struct acpi_bus_event *event = NULL;
290	unsigned long flags = 0;
291
292
293	if (!device)
294		return -EINVAL;
295
296	/* drop event on the floor if no one's listening */
297	if (!event_is_open)
298		return 0;
299
300	event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
301	if (!event)
302		return -ENOMEM;
303
304	strcpy(event->device_class, device->pnp.device_class);
305	strcpy(event->bus_id, device->pnp.bus_id);
306	event->type = type;
307	event->data = data;
308
309	spin_lock_irqsave(&acpi_bus_event_lock, flags);
310	list_add_tail(&event->node, &acpi_bus_event_list);
311	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
312
313	wake_up_interruptible(&acpi_bus_event_queue);
314
315	return 0;
316}
317
318EXPORT_SYMBOL(acpi_bus_generate_event);
319
320int acpi_bus_receive_event(struct acpi_bus_event *event)
321{
322	unsigned long flags = 0;
323	struct acpi_bus_event *entry = NULL;
324
325	DECLARE_WAITQUEUE(wait, current);
326
327
328	if (!event)
329		return -EINVAL;
330
331	if (list_empty(&acpi_bus_event_list)) {
332
333		set_current_state(TASK_INTERRUPTIBLE);
334		add_wait_queue(&acpi_bus_event_queue, &wait);
335
336		if (list_empty(&acpi_bus_event_list))
337			schedule();
338
339		remove_wait_queue(&acpi_bus_event_queue, &wait);
340		set_current_state(TASK_RUNNING);
341
342		if (signal_pending(current))
343			return -ERESTARTSYS;
344	}
345
346	spin_lock_irqsave(&acpi_bus_event_lock, flags);
347	entry =
348	    list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
349	if (entry)
350		list_del(&entry->node);
351	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
352
353	if (!entry)
354		return -ENODEV;
355
356	memcpy(event, entry, sizeof(struct acpi_bus_event));
357
358	kfree(entry);
359
360	return 0;
361}
362
363EXPORT_SYMBOL(acpi_bus_receive_event);
364
365/* --------------------------------------------------------------------------
366                             Notification Handling
367   -------------------------------------------------------------------------- */
368
369static int
370acpi_bus_check_device(struct acpi_device *device, int *status_changed)
371{
372	acpi_status status = 0;
373	struct acpi_device_status old_status;
374
375
376	if (!device)
377		return -EINVAL;
378
379	if (status_changed)
380		*status_changed = 0;
381
382	old_status = device->status;
383
384	/*
385	 * Make sure this device's parent is present before we go about
386	 * messing with the device.
387	 */
388	if (device->parent && !device->parent->status.present) {
389		device->status = device->parent->status;
390		if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
391			if (status_changed)
392				*status_changed = 1;
393		}
394		return 0;
395	}
396
397	status = acpi_bus_get_status(device);
398	if (ACPI_FAILURE(status))
399		return -ENODEV;
400
401	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
402		return 0;
403
404	if (status_changed)
405		*status_changed = 1;
406
407	/*
408	 * Device Insertion/Removal
409	 */
410	if ((device->status.present) && !(old_status.present)) {
411		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
412		/* TBD: Handle device insertion */
413	} else if (!(device->status.present) && (old_status.present)) {
414		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
415		/* TBD: Handle device removal */
416	}
417
418	return 0;
419}
420
421static int acpi_bus_check_scope(struct acpi_device *device)
422{
423	int result = 0;
424	int status_changed = 0;
425
426
427	if (!device)
428		return -EINVAL;
429
430	/* Status Change? */
431	result = acpi_bus_check_device(device, &status_changed);
432	if (result)
433		return result;
434
435	if (!status_changed)
436		return 0;
437
438	/*
439	 * TBD: Enumerate child devices within this device's scope and
440	 *       run acpi_bus_check_device()'s on them.
441	 */
442
443	return 0;
444}
445
446/**
447 * acpi_bus_notify
448 * ---------------
449 * Callback for all 'system-level' device notifications (values 0x00-0x7F).
450 */
451static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
452{
453	int result = 0;
454	struct acpi_device *device = NULL;
455
456
457	if (acpi_bus_get_device(handle, &device))
458		return;
459
460	switch (type) {
461
462	case ACPI_NOTIFY_BUS_CHECK:
463		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
464				  "Received BUS CHECK notification for device [%s]\n",
465				  device->pnp.bus_id));
466		result = acpi_bus_check_scope(device);
467		/*
468		 * TBD: We'll need to outsource certain events to non-ACPI
469		 *      drivers via the device manager (device.c).
470		 */
471		break;
472
473	case ACPI_NOTIFY_DEVICE_CHECK:
474		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
475				  "Received DEVICE CHECK notification for device [%s]\n",
476				  device->pnp.bus_id));
477		result = acpi_bus_check_device(device, NULL);
478		/*
479		 * TBD: We'll need to outsource certain events to non-ACPI
480		 *      drivers via the device manager (device.c).
481		 */
482		break;
483
484	case ACPI_NOTIFY_DEVICE_WAKE:
485		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
486				  "Received DEVICE WAKE notification for device [%s]\n",
487				  device->pnp.bus_id));
488		/* TBD */
489		break;
490
491	case ACPI_NOTIFY_EJECT_REQUEST:
492		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
493				  "Received EJECT REQUEST notification for device [%s]\n",
494				  device->pnp.bus_id));
495		/* TBD */
496		break;
497
498	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
499		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
500				  "Received DEVICE CHECK LIGHT notification for device [%s]\n",
501				  device->pnp.bus_id));
502		/* TBD: Exactly what does 'light' mean? */
503		break;
504
505	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
506		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
507				  "Received FREQUENCY MISMATCH notification for device [%s]\n",
508				  device->pnp.bus_id));
509		/* TBD */
510		break;
511
512	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
513		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
514				  "Received BUS MODE MISMATCH notification for device [%s]\n",
515				  device->pnp.bus_id));
516		/* TBD */
517		break;
518
519	case ACPI_NOTIFY_POWER_FAULT:
520		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
521				  "Received POWER FAULT notification for device [%s]\n",
522				  device->pnp.bus_id));
523		/* TBD */
524		break;
525
526	default:
527		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
528				  "Received unknown/unsupported notification [%08x]\n",
529				  type));
530		break;
531	}
532
533	return;
534}
535
536/* --------------------------------------------------------------------------
537                             Initialization/Cleanup
538   -------------------------------------------------------------------------- */
539
540static int __init acpi_bus_init_irq(void)
541{
542	acpi_status status = AE_OK;
543	union acpi_object arg = { ACPI_TYPE_INTEGER };
544	struct acpi_object_list arg_list = { 1, &arg };
545	char *message = NULL;
546
547
548	/*
549	 * Let the system know what interrupt model we are using by
550	 * evaluating the \_PIC object, if exists.
551	 */
552
553	switch (acpi_irq_model) {
554	case ACPI_IRQ_MODEL_PIC:
555		message = "PIC";
556		break;
557	case ACPI_IRQ_MODEL_IOAPIC:
558		message = "IOAPIC";
559		break;
560	case ACPI_IRQ_MODEL_IOSAPIC:
561		message = "IOSAPIC";
562		break;
563	default:
564		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
565		return -ENODEV;
566	}
567
568	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
569
570	arg.integer.value = acpi_irq_model;
571
572	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
573	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
574		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
575		return -ENODEV;
576	}
577
578	return 0;
579}
580
581void __init acpi_early_init(void)
582{
583	acpi_status status = AE_OK;
584	struct acpi_buffer buffer = { sizeof(acpi_fadt), &acpi_fadt };
585
586
587	if (acpi_disabled)
588		return;
589
590	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
591
592	/* enable workarounds, unless strict ACPI spec. compliance */
593	if (!acpi_strict)
594		acpi_gbl_enable_interpreter_slack = TRUE;
595
596	status = acpi_initialize_subsystem();
597	if (ACPI_FAILURE(status)) {
598		printk(KERN_ERR PREFIX
599		       "Unable to initialize the ACPI Interpreter\n");
600		goto error0;
601	}
602
603	status = acpi_load_tables();
604	if (ACPI_FAILURE(status)) {
605		printk(KERN_ERR PREFIX
606		       "Unable to load the System Description Tables\n");
607		goto error0;
608	}
609
610	/*
611	 * Get a separate copy of the FADT for use by other drivers.
612	 */
613	status = acpi_get_table(ACPI_TABLE_ID_FADT, 1, &buffer);
614	if (ACPI_FAILURE(status)) {
615		printk(KERN_ERR PREFIX "Unable to get the FADT\n");
616		goto error0;
617	}
618#ifdef CONFIG_X86
619	if (!acpi_ioapic) {
620		extern acpi_interrupt_flags acpi_sci_flags;
621
622		/* compatible (0) means level (3) */
623		if (acpi_sci_flags.trigger == 0)
624			acpi_sci_flags.trigger = 3;
625
626		/* Set PIC-mode SCI trigger type */
627		acpi_pic_sci_set_trigger(acpi_fadt.sci_int,
628					 acpi_sci_flags.trigger);
629	} else {
630		extern int acpi_sci_override_gsi;
631		/*
632		 * now that acpi_fadt is initialized,
633		 * update it with result from INT_SRC_OVR parsing
634		 */
635		acpi_fadt.sci_int = acpi_sci_override_gsi;
636	}
637#endif
638
639	status =
640	    acpi_enable_subsystem(~
641				  (ACPI_NO_HARDWARE_INIT |
642				   ACPI_NO_ACPI_ENABLE));
643	if (ACPI_FAILURE(status)) {
644		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
645		goto error0;
646	}
647
648	return;
649
650      error0:
651	disable_acpi();
652	return;
653}
654
655static int __init acpi_bus_init(void)
656{
657	int result = 0;
658	acpi_status status = AE_OK;
659	extern acpi_status acpi_os_initialize1(void);
660
661
662	status = acpi_os_initialize1();
663
664	status =
665	    acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
666	if (ACPI_FAILURE(status)) {
667		printk(KERN_ERR PREFIX
668		       "Unable to start the ACPI Interpreter\n");
669		goto error1;
670	}
671
672	if (ACPI_FAILURE(status)) {
673		printk(KERN_ERR PREFIX
674		       "Unable to initialize ACPI OS objects\n");
675		goto error1;
676	}
677#ifdef CONFIG_ACPI_EC
678	/*
679	 * ACPI 2.0 requires the EC driver to be loaded and work before
680	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
681	 * is called).
682	 *
683	 * This is accomplished by looking for the ECDT table, and getting
684	 * the EC parameters out of that.
685	 */
686	status = acpi_ec_ecdt_probe();
687	/* Ignore result. Not having an ECDT is not fatal. */
688#endif
689
690	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
691	if (ACPI_FAILURE(status)) {
692		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
693		goto error1;
694	}
695
696	printk(KERN_INFO PREFIX "Interpreter enabled\n");
697
698	/*
699	 * Get the system interrupt model and evaluate \_PIC.
700	 */
701	result = acpi_bus_init_irq();
702	if (result)
703		goto error1;
704
705	/*
706	 * Register the for all standard device notifications.
707	 */
708	status =
709	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
710					&acpi_bus_notify, NULL);
711	if (ACPI_FAILURE(status)) {
712		printk(KERN_ERR PREFIX
713		       "Unable to register for device notifications\n");
714		goto error1;
715	}
716
717	/*
718	 * Create the top ACPI proc directory
719	 */
720	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
721
722	return 0;
723
724	/* Mimic structured exception handling */
725      error1:
726	acpi_terminate();
727	return -ENODEV;
728}
729
730decl_subsys(acpi, NULL, NULL);
731
732static int __init acpi_init(void)
733{
734	int result = 0;
735
736
737	if (acpi_disabled) {
738		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
739		return -ENODEV;
740	}
741
742	result = firmware_register(&acpi_subsys);
743	if (result < 0)
744		printk(KERN_WARNING "%s: firmware_register error: %d\n",
745			__FUNCTION__, result);
746
747	result = acpi_bus_init();
748
749	if (!result) {
750#ifdef CONFIG_PM_LEGACY
751		if (!PM_IS_ACTIVE())
752			pm_active = 1;
753		else {
754			printk(KERN_INFO PREFIX
755			       "APM is already active, exiting\n");
756			disable_acpi();
757			result = -ENODEV;
758		}
759#endif
760	} else
761		disable_acpi();
762
763	return result;
764}
765
766subsys_initcall(acpi_init);
767