xref: /linux/drivers/acpi/bus.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 #include <linux/regulator/machine.h>
37 #ifdef CONFIG_X86
38 #include <asm/mpspec.h>
39 #endif
40 #include <linux/pci.h>
41 #include <acpi/apei.h>
42 #include <linux/dmi.h>
43 #include <linux/suspend.h>
44 
45 #include "internal.h"
46 
47 #define _COMPONENT		ACPI_BUS_COMPONENT
48 ACPI_MODULE_NAME("bus");
49 
50 struct acpi_device *acpi_root;
51 struct proc_dir_entry *acpi_root_dir;
52 EXPORT_SYMBOL(acpi_root_dir);
53 
54 #ifdef CONFIG_X86
55 #ifdef CONFIG_ACPI_CUSTOM_DSDT
56 static inline int set_copy_dsdt(const struct dmi_system_id *id)
57 {
58 	return 0;
59 }
60 #else
61 static int set_copy_dsdt(const struct dmi_system_id *id)
62 {
63 	printk(KERN_NOTICE "%s detected - "
64 		"force copy of DSDT to local memory\n", id->ident);
65 	acpi_gbl_copy_dsdt_locally = 1;
66 	return 0;
67 }
68 #endif
69 
70 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
71 	/*
72 	 * Invoke DSDT corruption work-around on all Toshiba Satellite.
73 	 * https://bugzilla.kernel.org/show_bug.cgi?id=14679
74 	 */
75 	{
76 	 .callback = set_copy_dsdt,
77 	 .ident = "TOSHIBA Satellite",
78 	 .matches = {
79 		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
80 		DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
81 		},
82 	},
83 	{}
84 };
85 #else
86 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
87 	{}
88 };
89 #endif
90 
91 /* --------------------------------------------------------------------------
92                                 Device Management
93    -------------------------------------------------------------------------- */
94 
95 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
96 				       unsigned long long *sta)
97 {
98 	acpi_status status;
99 
100 	status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
101 	if (ACPI_SUCCESS(status))
102 		return AE_OK;
103 
104 	if (status == AE_NOT_FOUND) {
105 		*sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
106 		       ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
107 		return AE_OK;
108 	}
109 	return status;
110 }
111 
112 int acpi_bus_get_status(struct acpi_device *device)
113 {
114 	acpi_status status;
115 	unsigned long long sta;
116 
117 	status = acpi_bus_get_status_handle(device->handle, &sta);
118 	if (ACPI_FAILURE(status))
119 		return -ENODEV;
120 
121 	acpi_set_device_status(device, sta);
122 
123 	if (device->status.functional && !device->status.present) {
124 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
125 		       "functional but not present;\n",
126 			device->pnp.bus_id, (u32)sta));
127 	}
128 
129 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
130 			  device->pnp.bus_id, (u32)sta));
131 	return 0;
132 }
133 EXPORT_SYMBOL(acpi_bus_get_status);
134 
135 void acpi_bus_private_data_handler(acpi_handle handle,
136 				   void *context)
137 {
138 	return;
139 }
140 EXPORT_SYMBOL(acpi_bus_private_data_handler);
141 
142 int acpi_bus_attach_private_data(acpi_handle handle, void *data)
143 {
144 	acpi_status status;
145 
146 	status = acpi_attach_data(handle,
147 			acpi_bus_private_data_handler, data);
148 	if (ACPI_FAILURE(status)) {
149 		acpi_handle_debug(handle, "Error attaching device data\n");
150 		return -ENODEV;
151 	}
152 
153 	return 0;
154 }
155 EXPORT_SYMBOL_GPL(acpi_bus_attach_private_data);
156 
157 int acpi_bus_get_private_data(acpi_handle handle, void **data)
158 {
159 	acpi_status status;
160 
161 	if (!*data)
162 		return -EINVAL;
163 
164 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
165 	if (ACPI_FAILURE(status)) {
166 		acpi_handle_debug(handle, "No context for object\n");
167 		return -ENODEV;
168 	}
169 
170 	return 0;
171 }
172 EXPORT_SYMBOL_GPL(acpi_bus_get_private_data);
173 
174 void acpi_bus_detach_private_data(acpi_handle handle)
175 {
176 	acpi_detach_data(handle, acpi_bus_private_data_handler);
177 }
178 EXPORT_SYMBOL_GPL(acpi_bus_detach_private_data);
179 
180 static void acpi_print_osc_error(acpi_handle handle,
181 	struct acpi_osc_context *context, char *error)
182 {
183 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
184 	int i;
185 
186 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
187 		printk(KERN_DEBUG "%s\n", error);
188 	else {
189 		printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
190 		kfree(buffer.pointer);
191 	}
192 	printk(KERN_DEBUG"_OSC request data:");
193 	for (i = 0; i < context->cap.length; i += sizeof(u32))
194 		printk("%x ", *((u32 *)(context->cap.pointer + i)));
195 	printk("\n");
196 }
197 
198 acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
199 {
200 	int i;
201 	static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
202 		24, 26, 28, 30, 32, 34};
203 
204 	if (strlen(str) != 36)
205 		return AE_BAD_PARAMETER;
206 	for (i = 0; i < 36; i++) {
207 		if (i == 8 || i == 13 || i == 18 || i == 23) {
208 			if (str[i] != '-')
209 				return AE_BAD_PARAMETER;
210 		} else if (!isxdigit(str[i]))
211 			return AE_BAD_PARAMETER;
212 	}
213 	for (i = 0; i < 16; i++) {
214 		uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
215 		uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
216 	}
217 	return AE_OK;
218 }
219 EXPORT_SYMBOL_GPL(acpi_str_to_uuid);
220 
221 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
222 {
223 	acpi_status status;
224 	struct acpi_object_list input;
225 	union acpi_object in_params[4];
226 	union acpi_object *out_obj;
227 	u8 uuid[16];
228 	u32 errors;
229 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
230 
231 	if (!context)
232 		return AE_ERROR;
233 	if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
234 		return AE_ERROR;
235 	context->ret.length = ACPI_ALLOCATE_BUFFER;
236 	context->ret.pointer = NULL;
237 
238 	/* Setting up input parameters */
239 	input.count = 4;
240 	input.pointer = in_params;
241 	in_params[0].type 		= ACPI_TYPE_BUFFER;
242 	in_params[0].buffer.length 	= 16;
243 	in_params[0].buffer.pointer	= uuid;
244 	in_params[1].type 		= ACPI_TYPE_INTEGER;
245 	in_params[1].integer.value 	= context->rev;
246 	in_params[2].type 		= ACPI_TYPE_INTEGER;
247 	in_params[2].integer.value	= context->cap.length/sizeof(u32);
248 	in_params[3].type		= ACPI_TYPE_BUFFER;
249 	in_params[3].buffer.length 	= context->cap.length;
250 	in_params[3].buffer.pointer 	= context->cap.pointer;
251 
252 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
253 	if (ACPI_FAILURE(status))
254 		return status;
255 
256 	if (!output.length)
257 		return AE_NULL_OBJECT;
258 
259 	out_obj = output.pointer;
260 	if (out_obj->type != ACPI_TYPE_BUFFER
261 		|| out_obj->buffer.length != context->cap.length) {
262 		acpi_print_osc_error(handle, context,
263 			"_OSC evaluation returned wrong type");
264 		status = AE_TYPE;
265 		goto out_kfree;
266 	}
267 	/* Need to ignore the bit0 in result code */
268 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
269 	if (errors) {
270 		if (errors & OSC_REQUEST_ERROR)
271 			acpi_print_osc_error(handle, context,
272 				"_OSC request failed");
273 		if (errors & OSC_INVALID_UUID_ERROR)
274 			acpi_print_osc_error(handle, context,
275 				"_OSC invalid UUID");
276 		if (errors & OSC_INVALID_REVISION_ERROR)
277 			acpi_print_osc_error(handle, context,
278 				"_OSC invalid revision");
279 		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
280 			if (((u32 *)context->cap.pointer)[OSC_QUERY_DWORD]
281 			    & OSC_QUERY_ENABLE)
282 				goto out_success;
283 			status = AE_SUPPORT;
284 			goto out_kfree;
285 		}
286 		status = AE_ERROR;
287 		goto out_kfree;
288 	}
289 out_success:
290 	context->ret.length = out_obj->buffer.length;
291 	context->ret.pointer = kmemdup(out_obj->buffer.pointer,
292 				       context->ret.length, GFP_KERNEL);
293 	if (!context->ret.pointer) {
294 		status =  AE_NO_MEMORY;
295 		goto out_kfree;
296 	}
297 	status =  AE_OK;
298 
299 out_kfree:
300 	kfree(output.pointer);
301 	if (status != AE_OK)
302 		context->ret.pointer = NULL;
303 	return status;
304 }
305 EXPORT_SYMBOL(acpi_run_osc);
306 
307 bool osc_sb_apei_support_acked;
308 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
309 static void acpi_bus_osc_support(void)
310 {
311 	u32 capbuf[2];
312 	struct acpi_osc_context context = {
313 		.uuid_str = sb_uuid_str,
314 		.rev = 1,
315 		.cap.length = 8,
316 		.cap.pointer = capbuf,
317 	};
318 	acpi_handle handle;
319 
320 	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
321 	capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
322 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
323 			defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
324 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
325 #endif
326 
327 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
328 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
329 #endif
330 
331 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
332 
333 	if (!ghes_disable)
334 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
335 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
336 		return;
337 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
338 		u32 *capbuf_ret = context.ret.pointer;
339 		if (context.ret.length > OSC_SUPPORT_DWORD)
340 			osc_sb_apei_support_acked =
341 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
342 		kfree(context.ret.pointer);
343 	}
344 	/* do we need to check other returned cap? Sounds no */
345 }
346 
347 /* --------------------------------------------------------------------------
348                              Notification Handling
349    -------------------------------------------------------------------------- */
350 
351 /**
352  * acpi_bus_notify
353  * ---------------
354  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
355  */
356 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
357 {
358 	struct acpi_device *adev;
359 	struct acpi_driver *driver;
360 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
361 	bool hotplug_event = false;
362 
363 	switch (type) {
364 	case ACPI_NOTIFY_BUS_CHECK:
365 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
366 		hotplug_event = true;
367 		break;
368 
369 	case ACPI_NOTIFY_DEVICE_CHECK:
370 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
371 		hotplug_event = true;
372 		break;
373 
374 	case ACPI_NOTIFY_DEVICE_WAKE:
375 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
376 		break;
377 
378 	case ACPI_NOTIFY_EJECT_REQUEST:
379 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
380 		hotplug_event = true;
381 		break;
382 
383 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
384 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
385 		/* TBD: Exactly what does 'light' mean? */
386 		break;
387 
388 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
389 		acpi_handle_err(handle, "Device cannot be configured due "
390 				"to a frequency mismatch\n");
391 		break;
392 
393 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
394 		acpi_handle_err(handle, "Device cannot be configured due "
395 				"to a bus mode mismatch\n");
396 		break;
397 
398 	case ACPI_NOTIFY_POWER_FAULT:
399 		acpi_handle_err(handle, "Device has suffered a power fault\n");
400 		break;
401 
402 	default:
403 		acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
404 		break;
405 	}
406 
407 	adev = acpi_bus_get_acpi_device(handle);
408 	if (!adev)
409 		goto err;
410 
411 	driver = adev->driver;
412 	if (driver && driver->ops.notify &&
413 	    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
414 		driver->ops.notify(adev, type);
415 
416 	if (hotplug_event && ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
417 		return;
418 
419 	acpi_bus_put_acpi_device(adev);
420 	return;
421 
422  err:
423 	acpi_evaluate_ost(handle, type, ost_code, NULL);
424 }
425 
426 /* --------------------------------------------------------------------------
427                              Initialization/Cleanup
428    -------------------------------------------------------------------------- */
429 
430 static int __init acpi_bus_init_irq(void)
431 {
432 	acpi_status status;
433 	char *message = NULL;
434 
435 
436 	/*
437 	 * Let the system know what interrupt model we are using by
438 	 * evaluating the \_PIC object, if exists.
439 	 */
440 
441 	switch (acpi_irq_model) {
442 	case ACPI_IRQ_MODEL_PIC:
443 		message = "PIC";
444 		break;
445 	case ACPI_IRQ_MODEL_IOAPIC:
446 		message = "IOAPIC";
447 		break;
448 	case ACPI_IRQ_MODEL_IOSAPIC:
449 		message = "IOSAPIC";
450 		break;
451 	case ACPI_IRQ_MODEL_GIC:
452 		message = "GIC";
453 		break;
454 	case ACPI_IRQ_MODEL_PLATFORM:
455 		message = "platform specific model";
456 		break;
457 	default:
458 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
459 		return -ENODEV;
460 	}
461 
462 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
463 
464 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
465 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
466 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
467 		return -ENODEV;
468 	}
469 
470 	return 0;
471 }
472 
473 void __init acpi_early_init(void)
474 {
475 	acpi_status status;
476 
477 	if (acpi_disabled)
478 		return;
479 
480 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
481 
482 	/* It's safe to verify table checksums during late stage */
483 	acpi_gbl_verify_table_checksum = TRUE;
484 
485 	/* enable workarounds, unless strict ACPI spec. compliance */
486 	if (!acpi_strict)
487 		acpi_gbl_enable_interpreter_slack = TRUE;
488 
489 	acpi_gbl_permanent_mmap = 1;
490 
491 	/*
492 	 * If the machine falls into the DMI check table,
493 	 * DSDT will be copied to memory
494 	 */
495 	dmi_check_system(dsdt_dmi_table);
496 
497 	status = acpi_reallocate_root_table();
498 	if (ACPI_FAILURE(status)) {
499 		printk(KERN_ERR PREFIX
500 		       "Unable to reallocate ACPI tables\n");
501 		goto error0;
502 	}
503 
504 	status = acpi_initialize_subsystem();
505 	if (ACPI_FAILURE(status)) {
506 		printk(KERN_ERR PREFIX
507 		       "Unable to initialize the ACPI Interpreter\n");
508 		goto error0;
509 	}
510 
511 	status = acpi_load_tables();
512 	if (ACPI_FAILURE(status)) {
513 		printk(KERN_ERR PREFIX
514 		       "Unable to load the System Description Tables\n");
515 		goto error0;
516 	}
517 
518 #ifdef CONFIG_X86
519 	if (!acpi_ioapic) {
520 		/* compatible (0) means level (3) */
521 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
522 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
523 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
524 		}
525 		/* Set PIC-mode SCI trigger type */
526 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
527 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
528 	} else {
529 		/*
530 		 * now that acpi_gbl_FADT is initialized,
531 		 * update it with result from INT_SRC_OVR parsing
532 		 */
533 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
534 	}
535 #endif
536 
537 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
538 	if (ACPI_FAILURE(status)) {
539 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
540 		goto error0;
541 	}
542 
543 	/*
544 	 * If the system is using ACPI then we can be reasonably
545 	 * confident that any regulators are managed by the firmware
546 	 * so tell the regulator core it has everything it needs to
547 	 * know.
548 	 */
549 	regulator_has_full_constraints();
550 
551 	return;
552 
553       error0:
554 	disable_acpi();
555 	return;
556 }
557 
558 static int __init acpi_bus_init(void)
559 {
560 	int result;
561 	acpi_status status;
562 
563 	acpi_os_initialize1();
564 
565 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
566 	if (ACPI_FAILURE(status)) {
567 		printk(KERN_ERR PREFIX
568 		       "Unable to start the ACPI Interpreter\n");
569 		goto error1;
570 	}
571 
572 	/*
573 	 * ACPI 2.0 requires the EC driver to be loaded and work before
574 	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
575 	 * is called).
576 	 *
577 	 * This is accomplished by looking for the ECDT table, and getting
578 	 * the EC parameters out of that.
579 	 */
580 	status = acpi_ec_ecdt_probe();
581 	/* Ignore result. Not having an ECDT is not fatal. */
582 
583 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
584 	if (ACPI_FAILURE(status)) {
585 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
586 		goto error1;
587 	}
588 
589 	/*
590 	 * _OSC method may exist in module level code,
591 	 * so it must be run after ACPI_FULL_INITIALIZATION
592 	 */
593 	acpi_bus_osc_support();
594 
595 	/*
596 	 * _PDC control method may load dynamic SSDT tables,
597 	 * and we need to install the table handler before that.
598 	 */
599 	acpi_sysfs_init();
600 
601 	acpi_early_processor_set_pdc();
602 
603 	/*
604 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
605 	 * is necessary to enable it as early as possible.
606 	 */
607 	acpi_boot_ec_enable();
608 
609 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
610 
611 	/* Initialize sleep structures */
612 	acpi_sleep_init();
613 
614 	/*
615 	 * Get the system interrupt model and evaluate \_PIC.
616 	 */
617 	result = acpi_bus_init_irq();
618 	if (result)
619 		goto error1;
620 
621 	/*
622 	 * Register the for all standard device notifications.
623 	 */
624 	status =
625 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
626 					&acpi_bus_notify, NULL);
627 	if (ACPI_FAILURE(status)) {
628 		printk(KERN_ERR PREFIX
629 		       "Unable to register for device notifications\n");
630 		goto error1;
631 	}
632 
633 	/*
634 	 * Create the top ACPI proc directory
635 	 */
636 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
637 
638 	return 0;
639 
640 	/* Mimic structured exception handling */
641       error1:
642 	acpi_terminate();
643 	return -ENODEV;
644 }
645 
646 struct kobject *acpi_kobj;
647 EXPORT_SYMBOL_GPL(acpi_kobj);
648 
649 static int __init acpi_init(void)
650 {
651 	int result;
652 
653 	if (acpi_disabled) {
654 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
655 		return -ENODEV;
656 	}
657 
658 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
659 	if (!acpi_kobj) {
660 		printk(KERN_WARNING "%s: kset create error\n", __func__);
661 		acpi_kobj = NULL;
662 	}
663 
664 	init_acpi_device_notify();
665 	result = acpi_bus_init();
666 	if (result) {
667 		disable_acpi();
668 		return result;
669 	}
670 
671 	pci_mmcfg_late_init();
672 	acpi_scan_init();
673 	acpi_ec_init();
674 	acpi_debugfs_init();
675 	acpi_sleep_proc_init();
676 	acpi_wakeup_device_init();
677 	return 0;
678 }
679 
680 subsys_initcall(acpi_init);
681