xref: /openbmc/linux/drivers/acpi/bus.c (revision 930beb5a)
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 void acpi_bus_no_hotplug(acpi_handle handle)
160 {
161 	struct acpi_device *adev = NULL;
162 
163 	acpi_bus_get_device(handle, &adev);
164 	if (adev)
165 		adev->flags.no_hotplug = true;
166 }
167 EXPORT_SYMBOL_GPL(acpi_bus_no_hotplug);
168 
169 static void acpi_print_osc_error(acpi_handle handle,
170 	struct acpi_osc_context *context, char *error)
171 {
172 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
173 	int i;
174 
175 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
176 		printk(KERN_DEBUG "%s\n", error);
177 	else {
178 		printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
179 		kfree(buffer.pointer);
180 	}
181 	printk(KERN_DEBUG"_OSC request data:");
182 	for (i = 0; i < context->cap.length; i += sizeof(u32))
183 		printk("%x ", *((u32 *)(context->cap.pointer + i)));
184 	printk("\n");
185 }
186 
187 acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
188 {
189 	int i;
190 	static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
191 		24, 26, 28, 30, 32, 34};
192 
193 	if (strlen(str) != 36)
194 		return AE_BAD_PARAMETER;
195 	for (i = 0; i < 36; i++) {
196 		if (i == 8 || i == 13 || i == 18 || i == 23) {
197 			if (str[i] != '-')
198 				return AE_BAD_PARAMETER;
199 		} else if (!isxdigit(str[i]))
200 			return AE_BAD_PARAMETER;
201 	}
202 	for (i = 0; i < 16; i++) {
203 		uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
204 		uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
205 	}
206 	return AE_OK;
207 }
208 EXPORT_SYMBOL_GPL(acpi_str_to_uuid);
209 
210 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
211 {
212 	acpi_status status;
213 	struct acpi_object_list input;
214 	union acpi_object in_params[4];
215 	union acpi_object *out_obj;
216 	u8 uuid[16];
217 	u32 errors;
218 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
219 
220 	if (!context)
221 		return AE_ERROR;
222 	if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
223 		return AE_ERROR;
224 	context->ret.length = ACPI_ALLOCATE_BUFFER;
225 	context->ret.pointer = NULL;
226 
227 	/* Setting up input parameters */
228 	input.count = 4;
229 	input.pointer = in_params;
230 	in_params[0].type 		= ACPI_TYPE_BUFFER;
231 	in_params[0].buffer.length 	= 16;
232 	in_params[0].buffer.pointer	= uuid;
233 	in_params[1].type 		= ACPI_TYPE_INTEGER;
234 	in_params[1].integer.value 	= context->rev;
235 	in_params[2].type 		= ACPI_TYPE_INTEGER;
236 	in_params[2].integer.value	= context->cap.length/sizeof(u32);
237 	in_params[3].type		= ACPI_TYPE_BUFFER;
238 	in_params[3].buffer.length 	= context->cap.length;
239 	in_params[3].buffer.pointer 	= context->cap.pointer;
240 
241 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
242 	if (ACPI_FAILURE(status))
243 		return status;
244 
245 	if (!output.length)
246 		return AE_NULL_OBJECT;
247 
248 	out_obj = output.pointer;
249 	if (out_obj->type != ACPI_TYPE_BUFFER
250 		|| out_obj->buffer.length != context->cap.length) {
251 		acpi_print_osc_error(handle, context,
252 			"_OSC evaluation returned wrong type");
253 		status = AE_TYPE;
254 		goto out_kfree;
255 	}
256 	/* Need to ignore the bit0 in result code */
257 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
258 	if (errors) {
259 		if (errors & OSC_REQUEST_ERROR)
260 			acpi_print_osc_error(handle, context,
261 				"_OSC request failed");
262 		if (errors & OSC_INVALID_UUID_ERROR)
263 			acpi_print_osc_error(handle, context,
264 				"_OSC invalid UUID");
265 		if (errors & OSC_INVALID_REVISION_ERROR)
266 			acpi_print_osc_error(handle, context,
267 				"_OSC invalid revision");
268 		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
269 			if (((u32 *)context->cap.pointer)[OSC_QUERY_DWORD]
270 			    & OSC_QUERY_ENABLE)
271 				goto out_success;
272 			status = AE_SUPPORT;
273 			goto out_kfree;
274 		}
275 		status = AE_ERROR;
276 		goto out_kfree;
277 	}
278 out_success:
279 	context->ret.length = out_obj->buffer.length;
280 	context->ret.pointer = kmemdup(out_obj->buffer.pointer,
281 				       context->ret.length, GFP_KERNEL);
282 	if (!context->ret.pointer) {
283 		status =  AE_NO_MEMORY;
284 		goto out_kfree;
285 	}
286 	status =  AE_OK;
287 
288 out_kfree:
289 	kfree(output.pointer);
290 	if (status != AE_OK)
291 		context->ret.pointer = NULL;
292 	return status;
293 }
294 EXPORT_SYMBOL(acpi_run_osc);
295 
296 bool osc_sb_apei_support_acked;
297 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
298 static void acpi_bus_osc_support(void)
299 {
300 	u32 capbuf[2];
301 	struct acpi_osc_context context = {
302 		.uuid_str = sb_uuid_str,
303 		.rev = 1,
304 		.cap.length = 8,
305 		.cap.pointer = capbuf,
306 	};
307 	acpi_handle handle;
308 
309 	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
310 	capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
311 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
312 			defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
313 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
314 #endif
315 
316 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
317 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
318 #endif
319 
320 #ifdef ACPI_HOTPLUG_OST
321 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
322 #endif
323 
324 	if (!ghes_disable)
325 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
326 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
327 		return;
328 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
329 		u32 *capbuf_ret = context.ret.pointer;
330 		if (context.ret.length > OSC_SUPPORT_DWORD)
331 			osc_sb_apei_support_acked =
332 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
333 		kfree(context.ret.pointer);
334 	}
335 	/* do we need to check other returned cap? Sounds no */
336 }
337 
338 /* --------------------------------------------------------------------------
339                              Notification Handling
340    -------------------------------------------------------------------------- */
341 
342 static void acpi_bus_check_device(acpi_handle handle)
343 {
344 	struct acpi_device *device;
345 	acpi_status status;
346 	struct acpi_device_status old_status;
347 
348 	if (acpi_bus_get_device(handle, &device))
349 		return;
350 	if (!device)
351 		return;
352 
353 	old_status = device->status;
354 
355 	/*
356 	 * Make sure this device's parent is present before we go about
357 	 * messing with the device.
358 	 */
359 	if (device->parent && !device->parent->status.present) {
360 		device->status = device->parent->status;
361 		return;
362 	}
363 
364 	status = acpi_bus_get_status(device);
365 	if (ACPI_FAILURE(status))
366 		return;
367 
368 	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
369 		return;
370 
371 	/*
372 	 * Device Insertion/Removal
373 	 */
374 	if ((device->status.present) && !(old_status.present)) {
375 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
376 		/* TBD: Handle device insertion */
377 	} else if (!(device->status.present) && (old_status.present)) {
378 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
379 		/* TBD: Handle device removal */
380 	}
381 }
382 
383 static void acpi_bus_check_scope(acpi_handle handle)
384 {
385 	/* Status Change? */
386 	acpi_bus_check_device(handle);
387 
388 	/*
389 	 * TBD: Enumerate child devices within this device's scope and
390 	 *       run acpi_bus_check_device()'s on them.
391 	 */
392 }
393 
394 /**
395  * acpi_bus_notify
396  * ---------------
397  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
398  */
399 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
400 {
401 	struct acpi_device *device = NULL;
402 	struct acpi_driver *driver;
403 
404 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
405 			  type, handle));
406 
407 	switch (type) {
408 
409 	case ACPI_NOTIFY_BUS_CHECK:
410 		acpi_bus_check_scope(handle);
411 		/*
412 		 * TBD: We'll need to outsource certain events to non-ACPI
413 		 *      drivers via the device manager (device.c).
414 		 */
415 		break;
416 
417 	case ACPI_NOTIFY_DEVICE_CHECK:
418 		acpi_bus_check_device(handle);
419 		/*
420 		 * TBD: We'll need to outsource certain events to non-ACPI
421 		 *      drivers via the device manager (device.c).
422 		 */
423 		break;
424 
425 	case ACPI_NOTIFY_DEVICE_WAKE:
426 		/* TBD */
427 		break;
428 
429 	case ACPI_NOTIFY_EJECT_REQUEST:
430 		/* TBD */
431 		break;
432 
433 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
434 		/* TBD: Exactly what does 'light' mean? */
435 		break;
436 
437 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
438 		/* TBD */
439 		break;
440 
441 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
442 		/* TBD */
443 		break;
444 
445 	case ACPI_NOTIFY_POWER_FAULT:
446 		/* TBD */
447 		break;
448 
449 	default:
450 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
451 				  "Received unknown/unsupported notification [%08x]\n",
452 				  type));
453 		break;
454 	}
455 
456 	acpi_bus_get_device(handle, &device);
457 	if (device) {
458 		driver = device->driver;
459 		if (driver && driver->ops.notify &&
460 		    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
461 			driver->ops.notify(device, type);
462 	}
463 }
464 
465 /* --------------------------------------------------------------------------
466                              Initialization/Cleanup
467    -------------------------------------------------------------------------- */
468 
469 static int __init acpi_bus_init_irq(void)
470 {
471 	acpi_status status;
472 	char *message = NULL;
473 
474 
475 	/*
476 	 * Let the system know what interrupt model we are using by
477 	 * evaluating the \_PIC object, if exists.
478 	 */
479 
480 	switch (acpi_irq_model) {
481 	case ACPI_IRQ_MODEL_PIC:
482 		message = "PIC";
483 		break;
484 	case ACPI_IRQ_MODEL_IOAPIC:
485 		message = "IOAPIC";
486 		break;
487 	case ACPI_IRQ_MODEL_IOSAPIC:
488 		message = "IOSAPIC";
489 		break;
490 	case ACPI_IRQ_MODEL_PLATFORM:
491 		message = "platform specific model";
492 		break;
493 	default:
494 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
495 		return -ENODEV;
496 	}
497 
498 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
499 
500 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
501 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
502 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
503 		return -ENODEV;
504 	}
505 
506 	return 0;
507 }
508 
509 u8 acpi_gbl_permanent_mmap;
510 
511 
512 void __init acpi_early_init(void)
513 {
514 	acpi_status status;
515 
516 	if (acpi_disabled)
517 		return;
518 
519 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
520 
521 	/* enable workarounds, unless strict ACPI spec. compliance */
522 	if (!acpi_strict)
523 		acpi_gbl_enable_interpreter_slack = TRUE;
524 
525 	acpi_gbl_permanent_mmap = 1;
526 
527 	/*
528 	 * If the machine falls into the DMI check table,
529 	 * DSDT will be copied to memory
530 	 */
531 	dmi_check_system(dsdt_dmi_table);
532 
533 	status = acpi_reallocate_root_table();
534 	if (ACPI_FAILURE(status)) {
535 		printk(KERN_ERR PREFIX
536 		       "Unable to reallocate ACPI tables\n");
537 		goto error0;
538 	}
539 
540 	status = acpi_initialize_subsystem();
541 	if (ACPI_FAILURE(status)) {
542 		printk(KERN_ERR PREFIX
543 		       "Unable to initialize the ACPI Interpreter\n");
544 		goto error0;
545 	}
546 
547 	status = acpi_load_tables();
548 	if (ACPI_FAILURE(status)) {
549 		printk(KERN_ERR PREFIX
550 		       "Unable to load the System Description Tables\n");
551 		goto error0;
552 	}
553 
554 #ifdef CONFIG_X86
555 	if (!acpi_ioapic) {
556 		/* compatible (0) means level (3) */
557 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
558 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
559 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
560 		}
561 		/* Set PIC-mode SCI trigger type */
562 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
563 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
564 	} else {
565 		/*
566 		 * now that acpi_gbl_FADT is initialized,
567 		 * update it with result from INT_SRC_OVR parsing
568 		 */
569 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
570 	}
571 #endif
572 
573 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
574 	if (ACPI_FAILURE(status)) {
575 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
576 		goto error0;
577 	}
578 
579 	return;
580 
581       error0:
582 	disable_acpi();
583 	return;
584 }
585 
586 static int __init acpi_bus_init(void)
587 {
588 	int result;
589 	acpi_status status;
590 
591 	acpi_os_initialize1();
592 
593 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
594 	if (ACPI_FAILURE(status)) {
595 		printk(KERN_ERR PREFIX
596 		       "Unable to start the ACPI Interpreter\n");
597 		goto error1;
598 	}
599 
600 	/*
601 	 * ACPI 2.0 requires the EC driver to be loaded and work before
602 	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
603 	 * is called).
604 	 *
605 	 * This is accomplished by looking for the ECDT table, and getting
606 	 * the EC parameters out of that.
607 	 */
608 	status = acpi_ec_ecdt_probe();
609 	/* Ignore result. Not having an ECDT is not fatal. */
610 
611 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
612 	if (ACPI_FAILURE(status)) {
613 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
614 		goto error1;
615 	}
616 
617 	/*
618 	 * _OSC method may exist in module level code,
619 	 * so it must be run after ACPI_FULL_INITIALIZATION
620 	 */
621 	acpi_bus_osc_support();
622 
623 	/*
624 	 * _PDC control method may load dynamic SSDT tables,
625 	 * and we need to install the table handler before that.
626 	 */
627 	acpi_sysfs_init();
628 
629 	acpi_early_processor_set_pdc();
630 
631 	/*
632 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
633 	 * is necessary to enable it as early as possible.
634 	 */
635 	acpi_boot_ec_enable();
636 
637 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
638 
639 	/* Initialize sleep structures */
640 	acpi_sleep_init();
641 
642 	/*
643 	 * Get the system interrupt model and evaluate \_PIC.
644 	 */
645 	result = acpi_bus_init_irq();
646 	if (result)
647 		goto error1;
648 
649 	/*
650 	 * Register the for all standard device notifications.
651 	 */
652 	status =
653 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
654 					&acpi_bus_notify, NULL);
655 	if (ACPI_FAILURE(status)) {
656 		printk(KERN_ERR PREFIX
657 		       "Unable to register for device notifications\n");
658 		goto error1;
659 	}
660 
661 	/*
662 	 * Create the top ACPI proc directory
663 	 */
664 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
665 
666 	return 0;
667 
668 	/* Mimic structured exception handling */
669       error1:
670 	acpi_terminate();
671 	return -ENODEV;
672 }
673 
674 struct kobject *acpi_kobj;
675 EXPORT_SYMBOL_GPL(acpi_kobj);
676 
677 static int __init acpi_init(void)
678 {
679 	int result;
680 
681 	if (acpi_disabled) {
682 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
683 		return -ENODEV;
684 	}
685 
686 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
687 	if (!acpi_kobj) {
688 		printk(KERN_WARNING "%s: kset create error\n", __func__);
689 		acpi_kobj = NULL;
690 	}
691 
692 	init_acpi_device_notify();
693 	result = acpi_bus_init();
694 	if (result) {
695 		disable_acpi();
696 		return result;
697 	}
698 
699 	pci_mmcfg_late_init();
700 	acpi_scan_init();
701 	acpi_ec_init();
702 	acpi_debugfs_init();
703 	acpi_sleep_proc_init();
704 	acpi_wakeup_device_init();
705 	return 0;
706 }
707 
708 subsys_initcall(acpi_init);
709