xref: /openbmc/linux/drivers/acpi/bus.c (revision e23feb16)
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 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
93 				       unsigned long long *sta)
94 {
95 	acpi_status status;
96 
97 	status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
98 	if (ACPI_SUCCESS(status))
99 		return AE_OK;
100 
101 	if (status == AE_NOT_FOUND) {
102 		*sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
103 		       ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
104 		return AE_OK;
105 	}
106 	return status;
107 }
108 
109 int acpi_bus_get_status(struct acpi_device *device)
110 {
111 	acpi_status status;
112 	unsigned long long sta;
113 
114 	status = acpi_bus_get_status_handle(device->handle, &sta);
115 	if (ACPI_FAILURE(status))
116 		return -ENODEV;
117 
118 	STRUCT_TO_INT(device->status) = (int) sta;
119 
120 	if (device->status.functional && !device->status.present) {
121 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
122 		       "functional but not present;\n",
123 			device->pnp.bus_id,
124 			(u32) STRUCT_TO_INT(device->status)));
125 	}
126 
127 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
128 			  device->pnp.bus_id,
129 			  (u32) STRUCT_TO_INT(device->status)));
130 	return 0;
131 }
132 EXPORT_SYMBOL(acpi_bus_get_status);
133 
134 void acpi_bus_private_data_handler(acpi_handle handle,
135 				   void *context)
136 {
137 	return;
138 }
139 EXPORT_SYMBOL(acpi_bus_private_data_handler);
140 
141 int acpi_bus_get_private_data(acpi_handle handle, void **data)
142 {
143 	acpi_status status;
144 
145 	if (!*data)
146 		return -EINVAL;
147 
148 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
149 	if (ACPI_FAILURE(status) || !*data) {
150 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
151 				handle));
152 		return -ENODEV;
153 	}
154 
155 	return 0;
156 }
157 EXPORT_SYMBOL(acpi_bus_get_private_data);
158 
159 static void acpi_print_osc_error(acpi_handle handle,
160 	struct acpi_osc_context *context, char *error)
161 {
162 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
163 	int i;
164 
165 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
166 		printk(KERN_DEBUG "%s\n", error);
167 	else {
168 		printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
169 		kfree(buffer.pointer);
170 	}
171 	printk(KERN_DEBUG"_OSC request data:");
172 	for (i = 0; i < context->cap.length; i += sizeof(u32))
173 		printk("%x ", *((u32 *)(context->cap.pointer + i)));
174 	printk("\n");
175 }
176 
177 static acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
178 {
179 	int i;
180 	static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
181 		24, 26, 28, 30, 32, 34};
182 
183 	if (strlen(str) != 36)
184 		return AE_BAD_PARAMETER;
185 	for (i = 0; i < 36; i++) {
186 		if (i == 8 || i == 13 || i == 18 || i == 23) {
187 			if (str[i] != '-')
188 				return AE_BAD_PARAMETER;
189 		} else if (!isxdigit(str[i]))
190 			return AE_BAD_PARAMETER;
191 	}
192 	for (i = 0; i < 16; i++) {
193 		uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
194 		uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
195 	}
196 	return AE_OK;
197 }
198 
199 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
200 {
201 	acpi_status status;
202 	struct acpi_object_list input;
203 	union acpi_object in_params[4];
204 	union acpi_object *out_obj;
205 	u8 uuid[16];
206 	u32 errors;
207 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
208 
209 	if (!context)
210 		return AE_ERROR;
211 	if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
212 		return AE_ERROR;
213 	context->ret.length = ACPI_ALLOCATE_BUFFER;
214 	context->ret.pointer = NULL;
215 
216 	/* Setting up input parameters */
217 	input.count = 4;
218 	input.pointer = in_params;
219 	in_params[0].type 		= ACPI_TYPE_BUFFER;
220 	in_params[0].buffer.length 	= 16;
221 	in_params[0].buffer.pointer	= uuid;
222 	in_params[1].type 		= ACPI_TYPE_INTEGER;
223 	in_params[1].integer.value 	= context->rev;
224 	in_params[2].type 		= ACPI_TYPE_INTEGER;
225 	in_params[2].integer.value	= context->cap.length/sizeof(u32);
226 	in_params[3].type		= ACPI_TYPE_BUFFER;
227 	in_params[3].buffer.length 	= context->cap.length;
228 	in_params[3].buffer.pointer 	= context->cap.pointer;
229 
230 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
231 	if (ACPI_FAILURE(status))
232 		return status;
233 
234 	if (!output.length)
235 		return AE_NULL_OBJECT;
236 
237 	out_obj = output.pointer;
238 	if (out_obj->type != ACPI_TYPE_BUFFER
239 		|| out_obj->buffer.length != context->cap.length) {
240 		acpi_print_osc_error(handle, context,
241 			"_OSC evaluation returned wrong type");
242 		status = AE_TYPE;
243 		goto out_kfree;
244 	}
245 	/* Need to ignore the bit0 in result code */
246 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
247 	if (errors) {
248 		if (errors & OSC_REQUEST_ERROR)
249 			acpi_print_osc_error(handle, context,
250 				"_OSC request failed");
251 		if (errors & OSC_INVALID_UUID_ERROR)
252 			acpi_print_osc_error(handle, context,
253 				"_OSC invalid UUID");
254 		if (errors & OSC_INVALID_REVISION_ERROR)
255 			acpi_print_osc_error(handle, context,
256 				"_OSC invalid revision");
257 		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
258 			if (((u32 *)context->cap.pointer)[OSC_QUERY_TYPE]
259 			    & OSC_QUERY_ENABLE)
260 				goto out_success;
261 			status = AE_SUPPORT;
262 			goto out_kfree;
263 		}
264 		status = AE_ERROR;
265 		goto out_kfree;
266 	}
267 out_success:
268 	context->ret.length = out_obj->buffer.length;
269 	context->ret.pointer = kmemdup(out_obj->buffer.pointer,
270 				       context->ret.length, GFP_KERNEL);
271 	if (!context->ret.pointer) {
272 		status =  AE_NO_MEMORY;
273 		goto out_kfree;
274 	}
275 	status =  AE_OK;
276 
277 out_kfree:
278 	kfree(output.pointer);
279 	if (status != AE_OK)
280 		context->ret.pointer = NULL;
281 	return status;
282 }
283 EXPORT_SYMBOL(acpi_run_osc);
284 
285 bool osc_sb_apei_support_acked;
286 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
287 static void acpi_bus_osc_support(void)
288 {
289 	u32 capbuf[2];
290 	struct acpi_osc_context context = {
291 		.uuid_str = sb_uuid_str,
292 		.rev = 1,
293 		.cap.length = 8,
294 		.cap.pointer = capbuf,
295 	};
296 	acpi_handle handle;
297 
298 	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
299 	capbuf[OSC_SUPPORT_TYPE] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
300 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
301 			defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
302 	capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PAD_SUPPORT;
303 #endif
304 
305 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
306 	capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PPC_OST_SUPPORT;
307 #endif
308 
309 #ifdef ACPI_HOTPLUG_OST
310 	capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_HOTPLUG_OST_SUPPORT;
311 #endif
312 
313 	if (!ghes_disable)
314 		capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_APEI_SUPPORT;
315 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
316 		return;
317 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
318 		u32 *capbuf_ret = context.ret.pointer;
319 		if (context.ret.length > OSC_SUPPORT_TYPE)
320 			osc_sb_apei_support_acked =
321 				capbuf_ret[OSC_SUPPORT_TYPE] & OSC_SB_APEI_SUPPORT;
322 		kfree(context.ret.pointer);
323 	}
324 	/* do we need to check other returned cap? Sounds no */
325 }
326 
327 /* --------------------------------------------------------------------------
328                              Notification Handling
329    -------------------------------------------------------------------------- */
330 
331 static void acpi_bus_check_device(acpi_handle handle)
332 {
333 	struct acpi_device *device;
334 	acpi_status status;
335 	struct acpi_device_status old_status;
336 
337 	if (acpi_bus_get_device(handle, &device))
338 		return;
339 	if (!device)
340 		return;
341 
342 	old_status = device->status;
343 
344 	/*
345 	 * Make sure this device's parent is present before we go about
346 	 * messing with the device.
347 	 */
348 	if (device->parent && !device->parent->status.present) {
349 		device->status = device->parent->status;
350 		return;
351 	}
352 
353 	status = acpi_bus_get_status(device);
354 	if (ACPI_FAILURE(status))
355 		return;
356 
357 	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
358 		return;
359 
360 	/*
361 	 * Device Insertion/Removal
362 	 */
363 	if ((device->status.present) && !(old_status.present)) {
364 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
365 		/* TBD: Handle device insertion */
366 	} else if (!(device->status.present) && (old_status.present)) {
367 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
368 		/* TBD: Handle device removal */
369 	}
370 }
371 
372 static void acpi_bus_check_scope(acpi_handle handle)
373 {
374 	/* Status Change? */
375 	acpi_bus_check_device(handle);
376 
377 	/*
378 	 * TBD: Enumerate child devices within this device's scope and
379 	 *       run acpi_bus_check_device()'s on them.
380 	 */
381 }
382 
383 /**
384  * acpi_bus_notify
385  * ---------------
386  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
387  */
388 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
389 {
390 	struct acpi_device *device = NULL;
391 	struct acpi_driver *driver;
392 
393 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
394 			  type, handle));
395 
396 	switch (type) {
397 
398 	case ACPI_NOTIFY_BUS_CHECK:
399 		acpi_bus_check_scope(handle);
400 		/*
401 		 * TBD: We'll need to outsource certain events to non-ACPI
402 		 *      drivers via the device manager (device.c).
403 		 */
404 		break;
405 
406 	case ACPI_NOTIFY_DEVICE_CHECK:
407 		acpi_bus_check_device(handle);
408 		/*
409 		 * TBD: We'll need to outsource certain events to non-ACPI
410 		 *      drivers via the device manager (device.c).
411 		 */
412 		break;
413 
414 	case ACPI_NOTIFY_DEVICE_WAKE:
415 		/* TBD */
416 		break;
417 
418 	case ACPI_NOTIFY_EJECT_REQUEST:
419 		/* TBD */
420 		break;
421 
422 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
423 		/* TBD: Exactly what does 'light' mean? */
424 		break;
425 
426 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
427 		/* TBD */
428 		break;
429 
430 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
431 		/* TBD */
432 		break;
433 
434 	case ACPI_NOTIFY_POWER_FAULT:
435 		/* TBD */
436 		break;
437 
438 	default:
439 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
440 				  "Received unknown/unsupported notification [%08x]\n",
441 				  type));
442 		break;
443 	}
444 
445 	acpi_bus_get_device(handle, &device);
446 	if (device) {
447 		driver = device->driver;
448 		if (driver && driver->ops.notify &&
449 		    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
450 			driver->ops.notify(device, type);
451 	}
452 }
453 
454 /* --------------------------------------------------------------------------
455                              Initialization/Cleanup
456    -------------------------------------------------------------------------- */
457 
458 static int __init acpi_bus_init_irq(void)
459 {
460 	acpi_status status;
461 	char *message = NULL;
462 
463 
464 	/*
465 	 * Let the system know what interrupt model we are using by
466 	 * evaluating the \_PIC object, if exists.
467 	 */
468 
469 	switch (acpi_irq_model) {
470 	case ACPI_IRQ_MODEL_PIC:
471 		message = "PIC";
472 		break;
473 	case ACPI_IRQ_MODEL_IOAPIC:
474 		message = "IOAPIC";
475 		break;
476 	case ACPI_IRQ_MODEL_IOSAPIC:
477 		message = "IOSAPIC";
478 		break;
479 	case ACPI_IRQ_MODEL_PLATFORM:
480 		message = "platform specific model";
481 		break;
482 	default:
483 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
484 		return -ENODEV;
485 	}
486 
487 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
488 
489 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
490 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
491 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
492 		return -ENODEV;
493 	}
494 
495 	return 0;
496 }
497 
498 u8 acpi_gbl_permanent_mmap;
499 
500 
501 void __init acpi_early_init(void)
502 {
503 	acpi_status status;
504 
505 	if (acpi_disabled)
506 		return;
507 
508 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
509 
510 	/* enable workarounds, unless strict ACPI spec. compliance */
511 	if (!acpi_strict)
512 		acpi_gbl_enable_interpreter_slack = TRUE;
513 
514 	acpi_gbl_permanent_mmap = 1;
515 
516 	/*
517 	 * If the machine falls into the DMI check table,
518 	 * DSDT will be copied to memory
519 	 */
520 	dmi_check_system(dsdt_dmi_table);
521 
522 	status = acpi_reallocate_root_table();
523 	if (ACPI_FAILURE(status)) {
524 		printk(KERN_ERR PREFIX
525 		       "Unable to reallocate ACPI tables\n");
526 		goto error0;
527 	}
528 
529 	status = acpi_initialize_subsystem();
530 	if (ACPI_FAILURE(status)) {
531 		printk(KERN_ERR PREFIX
532 		       "Unable to initialize the ACPI Interpreter\n");
533 		goto error0;
534 	}
535 
536 	status = acpi_load_tables();
537 	if (ACPI_FAILURE(status)) {
538 		printk(KERN_ERR PREFIX
539 		       "Unable to load the System Description Tables\n");
540 		goto error0;
541 	}
542 
543 #ifdef CONFIG_X86
544 	if (!acpi_ioapic) {
545 		/* compatible (0) means level (3) */
546 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
547 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
548 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
549 		}
550 		/* Set PIC-mode SCI trigger type */
551 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
552 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
553 	} else {
554 		/*
555 		 * now that acpi_gbl_FADT is initialized,
556 		 * update it with result from INT_SRC_OVR parsing
557 		 */
558 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
559 	}
560 #endif
561 
562 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
563 	if (ACPI_FAILURE(status)) {
564 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
565 		goto error0;
566 	}
567 
568 	return;
569 
570       error0:
571 	disable_acpi();
572 	return;
573 }
574 
575 static int __init acpi_bus_init(void)
576 {
577 	int result;
578 	acpi_status status;
579 
580 	acpi_os_initialize1();
581 
582 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
583 	if (ACPI_FAILURE(status)) {
584 		printk(KERN_ERR PREFIX
585 		       "Unable to start the ACPI Interpreter\n");
586 		goto error1;
587 	}
588 
589 	/*
590 	 * ACPI 2.0 requires the EC driver to be loaded and work before
591 	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
592 	 * is called).
593 	 *
594 	 * This is accomplished by looking for the ECDT table, and getting
595 	 * the EC parameters out of that.
596 	 */
597 	status = acpi_ec_ecdt_probe();
598 	/* Ignore result. Not having an ECDT is not fatal. */
599 
600 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
601 	if (ACPI_FAILURE(status)) {
602 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
603 		goto error1;
604 	}
605 
606 	/*
607 	 * _OSC method may exist in module level code,
608 	 * so it must be run after ACPI_FULL_INITIALIZATION
609 	 */
610 	acpi_bus_osc_support();
611 
612 	/*
613 	 * _PDC control method may load dynamic SSDT tables,
614 	 * and we need to install the table handler before that.
615 	 */
616 	acpi_sysfs_init();
617 
618 	acpi_early_processor_set_pdc();
619 
620 	/*
621 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
622 	 * is necessary to enable it as early as possible.
623 	 */
624 	acpi_boot_ec_enable();
625 
626 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
627 
628 	/* Initialize sleep structures */
629 	acpi_sleep_init();
630 
631 	/*
632 	 * Get the system interrupt model and evaluate \_PIC.
633 	 */
634 	result = acpi_bus_init_irq();
635 	if (result)
636 		goto error1;
637 
638 	/*
639 	 * Register the for all standard device notifications.
640 	 */
641 	status =
642 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
643 					&acpi_bus_notify, NULL);
644 	if (ACPI_FAILURE(status)) {
645 		printk(KERN_ERR PREFIX
646 		       "Unable to register for device notifications\n");
647 		goto error1;
648 	}
649 
650 	/*
651 	 * Create the top ACPI proc directory
652 	 */
653 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
654 
655 	return 0;
656 
657 	/* Mimic structured exception handling */
658       error1:
659 	acpi_terminate();
660 	return -ENODEV;
661 }
662 
663 struct kobject *acpi_kobj;
664 EXPORT_SYMBOL_GPL(acpi_kobj);
665 
666 static int __init acpi_init(void)
667 {
668 	int result;
669 
670 	if (acpi_disabled) {
671 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
672 		return -ENODEV;
673 	}
674 
675 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
676 	if (!acpi_kobj) {
677 		printk(KERN_WARNING "%s: kset create error\n", __func__);
678 		acpi_kobj = NULL;
679 	}
680 
681 	init_acpi_device_notify();
682 	result = acpi_bus_init();
683 	if (result) {
684 		disable_acpi();
685 		return result;
686 	}
687 
688 	pci_mmcfg_late_init();
689 	acpi_scan_init();
690 	acpi_ec_init();
691 	acpi_debugfs_init();
692 	acpi_sleep_proc_init();
693 	acpi_wakeup_device_init();
694 	return 0;
695 }
696 
697 subsys_initcall(acpi_init);
698