xref: /openbmc/linux/drivers/acpi/bus.c (revision ab73b751)
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/device.h>
33 #include <linux/proc_fs.h>
34 #include <linux/acpi.h>
35 #include <linux/slab.h>
36 #ifdef CONFIG_X86
37 #include <asm/mpspec.h>
38 #endif
39 #include <linux/pci.h>
40 #include <acpi/acpi_bus.h>
41 #include <acpi/acpi_drivers.h>
42 #include <acpi/apei.h>
43 #include <linux/dmi.h>
44 #include <linux/suspend.h>
45 
46 #include "internal.h"
47 
48 #define _COMPONENT		ACPI_BUS_COMPONENT
49 ACPI_MODULE_NAME("bus");
50 
51 struct acpi_device *acpi_root;
52 struct proc_dir_entry *acpi_root_dir;
53 EXPORT_SYMBOL(acpi_root_dir);
54 
55 #define STRUCT_TO_INT(s)	(*((int*)&s))
56 
57 
58 #ifdef CONFIG_X86
59 static int set_copy_dsdt(const struct dmi_system_id *id)
60 {
61 	printk(KERN_NOTICE "%s detected - "
62 		"force copy of DSDT to local memory\n", id->ident);
63 	acpi_gbl_copy_dsdt_locally = 1;
64 	return 0;
65 }
66 
67 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
68 	/*
69 	 * Invoke DSDT corruption work-around on all Toshiba Satellite.
70 	 * https://bugzilla.kernel.org/show_bug.cgi?id=14679
71 	 */
72 	{
73 	 .callback = set_copy_dsdt,
74 	 .ident = "TOSHIBA Satellite",
75 	 .matches = {
76 		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
77 		DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
78 		},
79 	},
80 	{}
81 };
82 #else
83 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
84 	{}
85 };
86 #endif
87 
88 /* --------------------------------------------------------------------------
89                                 Device Management
90    -------------------------------------------------------------------------- */
91 
92 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
93 {
94 	acpi_status status = AE_OK;
95 
96 
97 	if (!device)
98 		return -EINVAL;
99 
100 	/* TBD: Support fixed-feature devices */
101 
102 	status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
103 	if (ACPI_FAILURE(status) || !*device) {
104 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
105 				  handle));
106 		return -ENODEV;
107 	}
108 
109 	return 0;
110 }
111 
112 EXPORT_SYMBOL(acpi_bus_get_device);
113 
114 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
115 				       unsigned long long *sta)
116 {
117 	acpi_status status;
118 
119 	status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
120 	if (ACPI_SUCCESS(status))
121 		return AE_OK;
122 
123 	if (status == AE_NOT_FOUND) {
124 		*sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
125 		       ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
126 		return AE_OK;
127 	}
128 	return status;
129 }
130 
131 int acpi_bus_get_status(struct acpi_device *device)
132 {
133 	acpi_status status;
134 	unsigned long long sta;
135 
136 	status = acpi_bus_get_status_handle(device->handle, &sta);
137 	if (ACPI_FAILURE(status))
138 		return -ENODEV;
139 
140 	STRUCT_TO_INT(device->status) = (int) sta;
141 
142 	if (device->status.functional && !device->status.present) {
143 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
144 		       "functional but not present;\n",
145 			device->pnp.bus_id,
146 			(u32) STRUCT_TO_INT(device->status)));
147 	}
148 
149 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
150 			  device->pnp.bus_id,
151 			  (u32) STRUCT_TO_INT(device->status)));
152 	return 0;
153 }
154 EXPORT_SYMBOL(acpi_bus_get_status);
155 
156 void acpi_bus_private_data_handler(acpi_handle handle,
157 				   void *context)
158 {
159 	return;
160 }
161 EXPORT_SYMBOL(acpi_bus_private_data_handler);
162 
163 int acpi_bus_get_private_data(acpi_handle handle, void **data)
164 {
165 	acpi_status status = AE_OK;
166 
167 	if (!*data)
168 		return -EINVAL;
169 
170 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
171 	if (ACPI_FAILURE(status) || !*data) {
172 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
173 				handle));
174 		return -ENODEV;
175 	}
176 
177 	return 0;
178 }
179 EXPORT_SYMBOL(acpi_bus_get_private_data);
180 
181 /* --------------------------------------------------------------------------
182                                  Power Management
183    -------------------------------------------------------------------------- */
184 
185 static int __acpi_bus_get_power(struct acpi_device *device, int *state)
186 {
187 	int result = 0;
188 	acpi_status status = 0;
189 	unsigned long long psc = 0;
190 
191 	if (!device || !state)
192 		return -EINVAL;
193 
194 	*state = ACPI_STATE_UNKNOWN;
195 
196 	if (device->flags.power_manageable) {
197 		/*
198 		 * Get the device's power state either directly (via _PSC) or
199 		 * indirectly (via power resources).
200 		 */
201 		if (device->power.flags.power_resources) {
202 			result = acpi_power_get_inferred_state(device, state);
203 			if (result)
204 				return result;
205 		} else if (device->power.flags.explicit_get) {
206 			status = acpi_evaluate_integer(device->handle, "_PSC",
207 						       NULL, &psc);
208 			if (ACPI_FAILURE(status))
209 				return -ENODEV;
210 			*state = (int)psc;
211 		}
212 	} else {
213 		/* TBD: Non-recursive algorithm for walking up hierarchy. */
214 		*state = device->parent ?
215 			device->parent->power.state : ACPI_STATE_D0;
216 	}
217 
218 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
219 			  device->pnp.bus_id, *state));
220 
221 	return 0;
222 }
223 
224 
225 static int __acpi_bus_set_power(struct acpi_device *device, int state)
226 {
227 	int result = 0;
228 	acpi_status status = AE_OK;
229 	char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
230 
231 	if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
232 		return -EINVAL;
233 
234 	/* Make sure this is a valid target state */
235 
236 	if (state == device->power.state) {
237 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
238 				  state));
239 		return 0;
240 	}
241 
242 	if (!device->power.states[state].flags.valid) {
243 		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
244 		return -ENODEV;
245 	}
246 	if (device->parent && (state < device->parent->power.state)) {
247 		printk(KERN_WARNING PREFIX
248 			      "Cannot set device to a higher-powered"
249 			      " state than parent\n");
250 		return -ENODEV;
251 	}
252 
253 	/* For D3cold we should execute _PS3, not _PS4. */
254 	if (state == ACPI_STATE_D3_COLD)
255 		object_name[3] = '3';
256 
257 	/*
258 	 * Transition Power
259 	 * ----------------
260 	 * On transitions to a high-powered state we first apply power (via
261 	 * power resources) then evalute _PSx.  Conversly for transitions to
262 	 * a lower-powered state.
263 	 */
264 	if (state < device->power.state) {
265 		if (device->power.flags.power_resources) {
266 			result = acpi_power_transition(device, state);
267 			if (result)
268 				goto end;
269 		}
270 		if (device->power.states[state].flags.explicit_set) {
271 			status = acpi_evaluate_object(device->handle,
272 						      object_name, NULL, NULL);
273 			if (ACPI_FAILURE(status)) {
274 				result = -ENODEV;
275 				goto end;
276 			}
277 		}
278 	} else {
279 		if (device->power.states[state].flags.explicit_set) {
280 			status = acpi_evaluate_object(device->handle,
281 						      object_name, NULL, NULL);
282 			if (ACPI_FAILURE(status)) {
283 				result = -ENODEV;
284 				goto end;
285 			}
286 		}
287 		if (device->power.flags.power_resources) {
288 			result = acpi_power_transition(device, state);
289 			if (result)
290 				goto end;
291 		}
292 	}
293 
294       end:
295 	if (result)
296 		printk(KERN_WARNING PREFIX
297 			      "Device [%s] failed to transition to D%d\n",
298 			      device->pnp.bus_id, state);
299 	else {
300 		device->power.state = state;
301 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
302 				  "Device [%s] transitioned to D%d\n",
303 				  device->pnp.bus_id, state));
304 	}
305 
306 	return result;
307 }
308 
309 
310 int acpi_bus_set_power(acpi_handle handle, int state)
311 {
312 	struct acpi_device *device;
313 	int result;
314 
315 	result = acpi_bus_get_device(handle, &device);
316 	if (result)
317 		return result;
318 
319 	if (!device->flags.power_manageable) {
320 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
321 				"Device [%s] is not power manageable\n",
322 				dev_name(&device->dev)));
323 		return -ENODEV;
324 	}
325 
326 	return __acpi_bus_set_power(device, state);
327 }
328 EXPORT_SYMBOL(acpi_bus_set_power);
329 
330 
331 int acpi_bus_init_power(struct acpi_device *device)
332 {
333 	int state;
334 	int result;
335 
336 	if (!device)
337 		return -EINVAL;
338 
339 	device->power.state = ACPI_STATE_UNKNOWN;
340 
341 	result = __acpi_bus_get_power(device, &state);
342 	if (result)
343 		return result;
344 
345 	if (device->power.flags.power_resources)
346 		result = acpi_power_on_resources(device, state);
347 
348 	if (!result)
349 		device->power.state = state;
350 
351 	return result;
352 }
353 
354 
355 int acpi_bus_update_power(acpi_handle handle, int *state_p)
356 {
357 	struct acpi_device *device;
358 	int state;
359 	int result;
360 
361 	result = acpi_bus_get_device(handle, &device);
362 	if (result)
363 		return result;
364 
365 	result = __acpi_bus_get_power(device, &state);
366 	if (result)
367 		return result;
368 
369 	result = __acpi_bus_set_power(device, state);
370 	if (!result && state_p)
371 		*state_p = state;
372 
373 	return result;
374 }
375 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
376 
377 
378 bool acpi_bus_power_manageable(acpi_handle handle)
379 {
380 	struct acpi_device *device;
381 	int result;
382 
383 	result = acpi_bus_get_device(handle, &device);
384 	return result ? false : device->flags.power_manageable;
385 }
386 
387 EXPORT_SYMBOL(acpi_bus_power_manageable);
388 
389 bool acpi_bus_can_wakeup(acpi_handle handle)
390 {
391 	struct acpi_device *device;
392 	int result;
393 
394 	result = acpi_bus_get_device(handle, &device);
395 	return result ? false : device->wakeup.flags.valid;
396 }
397 
398 EXPORT_SYMBOL(acpi_bus_can_wakeup);
399 
400 static void acpi_print_osc_error(acpi_handle handle,
401 	struct acpi_osc_context *context, char *error)
402 {
403 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
404 	int i;
405 
406 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
407 		printk(KERN_DEBUG "%s\n", error);
408 	else {
409 		printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
410 		kfree(buffer.pointer);
411 	}
412 	printk(KERN_DEBUG"_OSC request data:");
413 	for (i = 0; i < context->cap.length; i += sizeof(u32))
414 		printk("%x ", *((u32 *)(context->cap.pointer + i)));
415 	printk("\n");
416 }
417 
418 static acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
419 {
420 	int i;
421 	static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
422 		24, 26, 28, 30, 32, 34};
423 
424 	if (strlen(str) != 36)
425 		return AE_BAD_PARAMETER;
426 	for (i = 0; i < 36; i++) {
427 		if (i == 8 || i == 13 || i == 18 || i == 23) {
428 			if (str[i] != '-')
429 				return AE_BAD_PARAMETER;
430 		} else if (!isxdigit(str[i]))
431 			return AE_BAD_PARAMETER;
432 	}
433 	for (i = 0; i < 16; i++) {
434 		uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
435 		uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
436 	}
437 	return AE_OK;
438 }
439 
440 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
441 {
442 	acpi_status status;
443 	struct acpi_object_list input;
444 	union acpi_object in_params[4];
445 	union acpi_object *out_obj;
446 	u8 uuid[16];
447 	u32 errors;
448 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
449 
450 	if (!context)
451 		return AE_ERROR;
452 	if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
453 		return AE_ERROR;
454 	context->ret.length = ACPI_ALLOCATE_BUFFER;
455 	context->ret.pointer = NULL;
456 
457 	/* Setting up input parameters */
458 	input.count = 4;
459 	input.pointer = in_params;
460 	in_params[0].type 		= ACPI_TYPE_BUFFER;
461 	in_params[0].buffer.length 	= 16;
462 	in_params[0].buffer.pointer	= uuid;
463 	in_params[1].type 		= ACPI_TYPE_INTEGER;
464 	in_params[1].integer.value 	= context->rev;
465 	in_params[2].type 		= ACPI_TYPE_INTEGER;
466 	in_params[2].integer.value	= context->cap.length/sizeof(u32);
467 	in_params[3].type		= ACPI_TYPE_BUFFER;
468 	in_params[3].buffer.length 	= context->cap.length;
469 	in_params[3].buffer.pointer 	= context->cap.pointer;
470 
471 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
472 	if (ACPI_FAILURE(status))
473 		return status;
474 
475 	if (!output.length)
476 		return AE_NULL_OBJECT;
477 
478 	out_obj = output.pointer;
479 	if (out_obj->type != ACPI_TYPE_BUFFER
480 		|| out_obj->buffer.length != context->cap.length) {
481 		acpi_print_osc_error(handle, context,
482 			"_OSC evaluation returned wrong type");
483 		status = AE_TYPE;
484 		goto out_kfree;
485 	}
486 	/* Need to ignore the bit0 in result code */
487 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
488 	if (errors) {
489 		if (errors & OSC_REQUEST_ERROR)
490 			acpi_print_osc_error(handle, context,
491 				"_OSC request failed");
492 		if (errors & OSC_INVALID_UUID_ERROR)
493 			acpi_print_osc_error(handle, context,
494 				"_OSC invalid UUID");
495 		if (errors & OSC_INVALID_REVISION_ERROR)
496 			acpi_print_osc_error(handle, context,
497 				"_OSC invalid revision");
498 		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
499 			if (((u32 *)context->cap.pointer)[OSC_QUERY_TYPE]
500 			    & OSC_QUERY_ENABLE)
501 				goto out_success;
502 			status = AE_SUPPORT;
503 			goto out_kfree;
504 		}
505 		status = AE_ERROR;
506 		goto out_kfree;
507 	}
508 out_success:
509 	context->ret.length = out_obj->buffer.length;
510 	context->ret.pointer = kmalloc(context->ret.length, GFP_KERNEL);
511 	if (!context->ret.pointer) {
512 		status =  AE_NO_MEMORY;
513 		goto out_kfree;
514 	}
515 	memcpy(context->ret.pointer, out_obj->buffer.pointer,
516 		context->ret.length);
517 	status =  AE_OK;
518 
519 out_kfree:
520 	kfree(output.pointer);
521 	if (status != AE_OK)
522 		context->ret.pointer = NULL;
523 	return status;
524 }
525 EXPORT_SYMBOL(acpi_run_osc);
526 
527 bool osc_sb_apei_support_acked;
528 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
529 static void acpi_bus_osc_support(void)
530 {
531 	u32 capbuf[2];
532 	struct acpi_osc_context context = {
533 		.uuid_str = sb_uuid_str,
534 		.rev = 1,
535 		.cap.length = 8,
536 		.cap.pointer = capbuf,
537 	};
538 	acpi_handle handle;
539 
540 	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
541 	capbuf[OSC_SUPPORT_TYPE] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
542 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
543 			defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
544 	capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PAD_SUPPORT;
545 #endif
546 
547 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
548 	capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PPC_OST_SUPPORT;
549 #endif
550 
551 	if (!ghes_disable)
552 		capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_APEI_SUPPORT;
553 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
554 		return;
555 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
556 		u32 *capbuf_ret = context.ret.pointer;
557 		if (context.ret.length > OSC_SUPPORT_TYPE)
558 			osc_sb_apei_support_acked =
559 				capbuf_ret[OSC_SUPPORT_TYPE] & OSC_SB_APEI_SUPPORT;
560 		kfree(context.ret.pointer);
561 	}
562 	/* do we need to check other returned cap? Sounds no */
563 }
564 
565 /* --------------------------------------------------------------------------
566                                 Event Management
567    -------------------------------------------------------------------------- */
568 
569 #ifdef CONFIG_ACPI_PROC_EVENT
570 static DEFINE_SPINLOCK(acpi_bus_event_lock);
571 
572 LIST_HEAD(acpi_bus_event_list);
573 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
574 
575 extern int event_is_open;
576 
577 int acpi_bus_generate_proc_event4(const char *device_class, const char *bus_id, u8 type, int data)
578 {
579 	struct acpi_bus_event *event;
580 	unsigned long flags = 0;
581 
582 	/* drop event on the floor if no one's listening */
583 	if (!event_is_open)
584 		return 0;
585 
586 	event = kzalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
587 	if (!event)
588 		return -ENOMEM;
589 
590 	strcpy(event->device_class, device_class);
591 	strcpy(event->bus_id, bus_id);
592 	event->type = type;
593 	event->data = data;
594 
595 	spin_lock_irqsave(&acpi_bus_event_lock, flags);
596 	list_add_tail(&event->node, &acpi_bus_event_list);
597 	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
598 
599 	wake_up_interruptible(&acpi_bus_event_queue);
600 
601 	return 0;
602 
603 }
604 
605 EXPORT_SYMBOL_GPL(acpi_bus_generate_proc_event4);
606 
607 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data)
608 {
609 	if (!device)
610 		return -EINVAL;
611 	return acpi_bus_generate_proc_event4(device->pnp.device_class,
612 					     device->pnp.bus_id, type, data);
613 }
614 
615 EXPORT_SYMBOL(acpi_bus_generate_proc_event);
616 
617 int acpi_bus_receive_event(struct acpi_bus_event *event)
618 {
619 	unsigned long flags = 0;
620 	struct acpi_bus_event *entry = NULL;
621 
622 	DECLARE_WAITQUEUE(wait, current);
623 
624 
625 	if (!event)
626 		return -EINVAL;
627 
628 	if (list_empty(&acpi_bus_event_list)) {
629 
630 		set_current_state(TASK_INTERRUPTIBLE);
631 		add_wait_queue(&acpi_bus_event_queue, &wait);
632 
633 		if (list_empty(&acpi_bus_event_list))
634 			schedule();
635 
636 		remove_wait_queue(&acpi_bus_event_queue, &wait);
637 		set_current_state(TASK_RUNNING);
638 
639 		if (signal_pending(current))
640 			return -ERESTARTSYS;
641 	}
642 
643 	spin_lock_irqsave(&acpi_bus_event_lock, flags);
644 	if (!list_empty(&acpi_bus_event_list)) {
645 		entry = list_entry(acpi_bus_event_list.next,
646 				   struct acpi_bus_event, node);
647 		list_del(&entry->node);
648 	}
649 	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
650 
651 	if (!entry)
652 		return -ENODEV;
653 
654 	memcpy(event, entry, sizeof(struct acpi_bus_event));
655 
656 	kfree(entry);
657 
658 	return 0;
659 }
660 
661 #endif	/* CONFIG_ACPI_PROC_EVENT */
662 
663 /* --------------------------------------------------------------------------
664                              Notification Handling
665    -------------------------------------------------------------------------- */
666 
667 static void acpi_bus_check_device(acpi_handle handle)
668 {
669 	struct acpi_device *device;
670 	acpi_status status;
671 	struct acpi_device_status old_status;
672 
673 	if (acpi_bus_get_device(handle, &device))
674 		return;
675 	if (!device)
676 		return;
677 
678 	old_status = device->status;
679 
680 	/*
681 	 * Make sure this device's parent is present before we go about
682 	 * messing with the device.
683 	 */
684 	if (device->parent && !device->parent->status.present) {
685 		device->status = device->parent->status;
686 		return;
687 	}
688 
689 	status = acpi_bus_get_status(device);
690 	if (ACPI_FAILURE(status))
691 		return;
692 
693 	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
694 		return;
695 
696 	/*
697 	 * Device Insertion/Removal
698 	 */
699 	if ((device->status.present) && !(old_status.present)) {
700 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
701 		/* TBD: Handle device insertion */
702 	} else if (!(device->status.present) && (old_status.present)) {
703 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
704 		/* TBD: Handle device removal */
705 	}
706 }
707 
708 static void acpi_bus_check_scope(acpi_handle handle)
709 {
710 	/* Status Change? */
711 	acpi_bus_check_device(handle);
712 
713 	/*
714 	 * TBD: Enumerate child devices within this device's scope and
715 	 *       run acpi_bus_check_device()'s on them.
716 	 */
717 }
718 
719 static BLOCKING_NOTIFIER_HEAD(acpi_bus_notify_list);
720 int register_acpi_bus_notifier(struct notifier_block *nb)
721 {
722 	return blocking_notifier_chain_register(&acpi_bus_notify_list, nb);
723 }
724 EXPORT_SYMBOL_GPL(register_acpi_bus_notifier);
725 
726 void unregister_acpi_bus_notifier(struct notifier_block *nb)
727 {
728 	blocking_notifier_chain_unregister(&acpi_bus_notify_list, nb);
729 }
730 EXPORT_SYMBOL_GPL(unregister_acpi_bus_notifier);
731 
732 /**
733  * acpi_bus_notify
734  * ---------------
735  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
736  */
737 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
738 {
739 	struct acpi_device *device = NULL;
740 	struct acpi_driver *driver;
741 
742 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
743 			  type, handle));
744 
745 	blocking_notifier_call_chain(&acpi_bus_notify_list,
746 		type, (void *)handle);
747 
748 	switch (type) {
749 
750 	case ACPI_NOTIFY_BUS_CHECK:
751 		acpi_bus_check_scope(handle);
752 		/*
753 		 * TBD: We'll need to outsource certain events to non-ACPI
754 		 *      drivers via the device manager (device.c).
755 		 */
756 		break;
757 
758 	case ACPI_NOTIFY_DEVICE_CHECK:
759 		acpi_bus_check_device(handle);
760 		/*
761 		 * TBD: We'll need to outsource certain events to non-ACPI
762 		 *      drivers via the device manager (device.c).
763 		 */
764 		break;
765 
766 	case ACPI_NOTIFY_DEVICE_WAKE:
767 		/* TBD */
768 		break;
769 
770 	case ACPI_NOTIFY_EJECT_REQUEST:
771 		/* TBD */
772 		break;
773 
774 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
775 		/* TBD: Exactly what does 'light' mean? */
776 		break;
777 
778 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
779 		/* TBD */
780 		break;
781 
782 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
783 		/* TBD */
784 		break;
785 
786 	case ACPI_NOTIFY_POWER_FAULT:
787 		/* TBD */
788 		break;
789 
790 	default:
791 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
792 				  "Received unknown/unsupported notification [%08x]\n",
793 				  type));
794 		break;
795 	}
796 
797 	acpi_bus_get_device(handle, &device);
798 	if (device) {
799 		driver = device->driver;
800 		if (driver && driver->ops.notify &&
801 		    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
802 			driver->ops.notify(device, type);
803 	}
804 }
805 
806 /* --------------------------------------------------------------------------
807                              Initialization/Cleanup
808    -------------------------------------------------------------------------- */
809 
810 static int __init acpi_bus_init_irq(void)
811 {
812 	acpi_status status = AE_OK;
813 	union acpi_object arg = { ACPI_TYPE_INTEGER };
814 	struct acpi_object_list arg_list = { 1, &arg };
815 	char *message = NULL;
816 
817 
818 	/*
819 	 * Let the system know what interrupt model we are using by
820 	 * evaluating the \_PIC object, if exists.
821 	 */
822 
823 	switch (acpi_irq_model) {
824 	case ACPI_IRQ_MODEL_PIC:
825 		message = "PIC";
826 		break;
827 	case ACPI_IRQ_MODEL_IOAPIC:
828 		message = "IOAPIC";
829 		break;
830 	case ACPI_IRQ_MODEL_IOSAPIC:
831 		message = "IOSAPIC";
832 		break;
833 	case ACPI_IRQ_MODEL_PLATFORM:
834 		message = "platform specific model";
835 		break;
836 	default:
837 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
838 		return -ENODEV;
839 	}
840 
841 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
842 
843 	arg.integer.value = acpi_irq_model;
844 
845 	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
846 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
847 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
848 		return -ENODEV;
849 	}
850 
851 	return 0;
852 }
853 
854 u8 acpi_gbl_permanent_mmap;
855 
856 
857 void __init acpi_early_init(void)
858 {
859 	acpi_status status = AE_OK;
860 
861 	if (acpi_disabled)
862 		return;
863 
864 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
865 
866 	/* enable workarounds, unless strict ACPI spec. compliance */
867 	if (!acpi_strict)
868 		acpi_gbl_enable_interpreter_slack = TRUE;
869 
870 	acpi_gbl_permanent_mmap = 1;
871 
872 	/*
873 	 * If the machine falls into the DMI check table,
874 	 * DSDT will be copied to memory
875 	 */
876 	dmi_check_system(dsdt_dmi_table);
877 
878 	status = acpi_reallocate_root_table();
879 	if (ACPI_FAILURE(status)) {
880 		printk(KERN_ERR PREFIX
881 		       "Unable to reallocate ACPI tables\n");
882 		goto error0;
883 	}
884 
885 	status = acpi_initialize_subsystem();
886 	if (ACPI_FAILURE(status)) {
887 		printk(KERN_ERR PREFIX
888 		       "Unable to initialize the ACPI Interpreter\n");
889 		goto error0;
890 	}
891 
892 	status = acpi_load_tables();
893 	if (ACPI_FAILURE(status)) {
894 		printk(KERN_ERR PREFIX
895 		       "Unable to load the System Description Tables\n");
896 		goto error0;
897 	}
898 
899 #ifdef CONFIG_X86
900 	if (!acpi_ioapic) {
901 		/* compatible (0) means level (3) */
902 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
903 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
904 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
905 		}
906 		/* Set PIC-mode SCI trigger type */
907 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
908 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
909 	} else {
910 		/*
911 		 * now that acpi_gbl_FADT is initialized,
912 		 * update it with result from INT_SRC_OVR parsing
913 		 */
914 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
915 	}
916 #endif
917 
918 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
919 	if (ACPI_FAILURE(status)) {
920 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
921 		goto error0;
922 	}
923 
924 	return;
925 
926       error0:
927 	disable_acpi();
928 	return;
929 }
930 
931 static int __init acpi_bus_init(void)
932 {
933 	int result = 0;
934 	acpi_status status = AE_OK;
935 	extern acpi_status acpi_os_initialize1(void);
936 
937 	acpi_os_initialize1();
938 
939 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
940 	if (ACPI_FAILURE(status)) {
941 		printk(KERN_ERR PREFIX
942 		       "Unable to start the ACPI Interpreter\n");
943 		goto error1;
944 	}
945 
946 	/*
947 	 * ACPI 2.0 requires the EC driver to be loaded and work before
948 	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
949 	 * is called).
950 	 *
951 	 * This is accomplished by looking for the ECDT table, and getting
952 	 * the EC parameters out of that.
953 	 */
954 	status = acpi_ec_ecdt_probe();
955 	/* Ignore result. Not having an ECDT is not fatal. */
956 
957 	acpi_bus_osc_support();
958 
959 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
960 	if (ACPI_FAILURE(status)) {
961 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
962 		goto error1;
963 	}
964 
965 	/*
966 	 * _PDC control method may load dynamic SSDT tables,
967 	 * and we need to install the table handler before that.
968 	 */
969 	acpi_sysfs_init();
970 
971 	acpi_early_processor_set_pdc();
972 
973 	/*
974 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
975 	 * is necessary to enable it as early as possible.
976 	 */
977 	acpi_boot_ec_enable();
978 
979 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
980 
981 	/* Initialize sleep structures */
982 	acpi_sleep_init();
983 
984 	/*
985 	 * Get the system interrupt model and evaluate \_PIC.
986 	 */
987 	result = acpi_bus_init_irq();
988 	if (result)
989 		goto error1;
990 
991 	/*
992 	 * Register the for all standard device notifications.
993 	 */
994 	status =
995 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
996 					&acpi_bus_notify, NULL);
997 	if (ACPI_FAILURE(status)) {
998 		printk(KERN_ERR PREFIX
999 		       "Unable to register for device notifications\n");
1000 		goto error1;
1001 	}
1002 
1003 	/*
1004 	 * Create the top ACPI proc directory
1005 	 */
1006 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
1007 
1008 	return 0;
1009 
1010 	/* Mimic structured exception handling */
1011       error1:
1012 	acpi_terminate();
1013 	return -ENODEV;
1014 }
1015 
1016 struct kobject *acpi_kobj;
1017 EXPORT_SYMBOL_GPL(acpi_kobj);
1018 
1019 static int __init acpi_init(void)
1020 {
1021 	int result;
1022 
1023 	if (acpi_disabled) {
1024 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
1025 		return -ENODEV;
1026 	}
1027 
1028 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
1029 	if (!acpi_kobj) {
1030 		printk(KERN_WARNING "%s: kset create error\n", __func__);
1031 		acpi_kobj = NULL;
1032 	}
1033 
1034 	init_acpi_device_notify();
1035 	result = acpi_bus_init();
1036 	if (result) {
1037 		disable_acpi();
1038 		return result;
1039 	}
1040 
1041 	pci_mmcfg_late_init();
1042 	acpi_scan_init();
1043 	acpi_ec_init();
1044 	acpi_debugfs_init();
1045 	acpi_sleep_proc_init();
1046 	acpi_wakeup_device_init();
1047 	return 0;
1048 }
1049 
1050 subsys_initcall(acpi_init);
1051