xref: /openbmc/linux/drivers/acpi/bus.c (revision 1e726951)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
4  *
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  */
7 
8 #define pr_fmt(fmt) "ACPI: " fmt
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/ioport.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/sched.h>
16 #include <linux/pm.h>
17 #include <linux/device.h>
18 #include <linux/proc_fs.h>
19 #include <linux/acpi.h>
20 #include <linux/slab.h>
21 #include <linux/regulator/machine.h>
22 #include <linux/workqueue.h>
23 #include <linux/reboot.h>
24 #include <linux/delay.h>
25 #ifdef CONFIG_X86
26 #include <asm/mpspec.h>
27 #include <linux/dmi.h>
28 #endif
29 #include <linux/acpi_agdi.h>
30 #include <linux/acpi_apmt.h>
31 #include <linux/acpi_iort.h>
32 #include <linux/acpi_viot.h>
33 #include <linux/pci.h>
34 #include <acpi/apei.h>
35 #include <linux/suspend.h>
36 #include <linux/prmt.h>
37 
38 #include "internal.h"
39 
40 struct acpi_device *acpi_root;
41 struct proc_dir_entry *acpi_root_dir;
42 EXPORT_SYMBOL(acpi_root_dir);
43 
44 #ifdef CONFIG_X86
45 #ifdef CONFIG_ACPI_CUSTOM_DSDT
46 static inline int set_copy_dsdt(const struct dmi_system_id *id)
47 {
48 	return 0;
49 }
50 #else
51 static int set_copy_dsdt(const struct dmi_system_id *id)
52 {
53 	pr_notice("%s detected - force copy of DSDT to local memory\n", id->ident);
54 	acpi_gbl_copy_dsdt_locally = 1;
55 	return 0;
56 }
57 #endif
58 
59 static const struct dmi_system_id dsdt_dmi_table[] __initconst = {
60 	/*
61 	 * Invoke DSDT corruption work-around on all Toshiba Satellite.
62 	 * https://bugzilla.kernel.org/show_bug.cgi?id=14679
63 	 */
64 	{
65 	 .callback = set_copy_dsdt,
66 	 .ident = "TOSHIBA Satellite",
67 	 .matches = {
68 		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
69 		DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
70 		},
71 	},
72 	{}
73 };
74 #endif
75 
76 /* --------------------------------------------------------------------------
77                                 Device Management
78    -------------------------------------------------------------------------- */
79 
80 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
81 				       unsigned long long *sta)
82 {
83 	acpi_status status;
84 
85 	status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
86 	if (ACPI_SUCCESS(status))
87 		return AE_OK;
88 
89 	if (status == AE_NOT_FOUND) {
90 		*sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
91 		       ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
92 		return AE_OK;
93 	}
94 	return status;
95 }
96 EXPORT_SYMBOL_GPL(acpi_bus_get_status_handle);
97 
98 int acpi_bus_get_status(struct acpi_device *device)
99 {
100 	acpi_status status;
101 	unsigned long long sta;
102 
103 	if (acpi_device_override_status(device, &sta)) {
104 		acpi_set_device_status(device, sta);
105 		return 0;
106 	}
107 
108 	/* Battery devices must have their deps met before calling _STA */
109 	if (acpi_device_is_battery(device) && device->dep_unmet) {
110 		acpi_set_device_status(device, 0);
111 		return 0;
112 	}
113 
114 	status = acpi_bus_get_status_handle(device->handle, &sta);
115 	if (ACPI_FAILURE(status))
116 		return -ENODEV;
117 
118 	acpi_set_device_status(device, sta);
119 
120 	if (device->status.functional && !device->status.present) {
121 		pr_debug("Device [%s] status [%08x]: functional but not present\n",
122 			 device->pnp.bus_id, (u32)sta);
123 	}
124 
125 	pr_debug("Device [%s] status [%08x]\n", device->pnp.bus_id, (u32)sta);
126 	return 0;
127 }
128 EXPORT_SYMBOL(acpi_bus_get_status);
129 
130 void acpi_bus_private_data_handler(acpi_handle handle,
131 				   void *context)
132 {
133 	return;
134 }
135 EXPORT_SYMBOL(acpi_bus_private_data_handler);
136 
137 int acpi_bus_attach_private_data(acpi_handle handle, void *data)
138 {
139 	acpi_status status;
140 
141 	status = acpi_attach_data(handle,
142 			acpi_bus_private_data_handler, data);
143 	if (ACPI_FAILURE(status)) {
144 		acpi_handle_debug(handle, "Error attaching device data\n");
145 		return -ENODEV;
146 	}
147 
148 	return 0;
149 }
150 EXPORT_SYMBOL_GPL(acpi_bus_attach_private_data);
151 
152 int acpi_bus_get_private_data(acpi_handle handle, void **data)
153 {
154 	acpi_status status;
155 
156 	if (!data)
157 		return -EINVAL;
158 
159 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
160 	if (ACPI_FAILURE(status)) {
161 		acpi_handle_debug(handle, "No context for object\n");
162 		return -ENODEV;
163 	}
164 
165 	return 0;
166 }
167 EXPORT_SYMBOL_GPL(acpi_bus_get_private_data);
168 
169 void acpi_bus_detach_private_data(acpi_handle handle)
170 {
171 	acpi_detach_data(handle, acpi_bus_private_data_handler);
172 }
173 EXPORT_SYMBOL_GPL(acpi_bus_detach_private_data);
174 
175 static void acpi_print_osc_error(acpi_handle handle,
176 				 struct acpi_osc_context *context, char *error)
177 {
178 	int i;
179 
180 	acpi_handle_debug(handle, "(%s): %s\n", context->uuid_str, error);
181 
182 	pr_debug("_OSC request data:");
183 	for (i = 0; i < context->cap.length; i += sizeof(u32))
184 		pr_debug(" %x", *((u32 *)(context->cap.pointer + i)));
185 
186 	pr_debug("\n");
187 }
188 
189 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
190 {
191 	acpi_status status;
192 	struct acpi_object_list input;
193 	union acpi_object in_params[4];
194 	union acpi_object *out_obj;
195 	guid_t guid;
196 	u32 errors;
197 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
198 
199 	if (!context)
200 		return AE_ERROR;
201 	if (guid_parse(context->uuid_str, &guid))
202 		return AE_ERROR;
203 	context->ret.length = ACPI_ALLOCATE_BUFFER;
204 	context->ret.pointer = NULL;
205 
206 	/* Setting up input parameters */
207 	input.count = 4;
208 	input.pointer = in_params;
209 	in_params[0].type 		= ACPI_TYPE_BUFFER;
210 	in_params[0].buffer.length 	= 16;
211 	in_params[0].buffer.pointer	= (u8 *)&guid;
212 	in_params[1].type 		= ACPI_TYPE_INTEGER;
213 	in_params[1].integer.value 	= context->rev;
214 	in_params[2].type 		= ACPI_TYPE_INTEGER;
215 	in_params[2].integer.value	= context->cap.length/sizeof(u32);
216 	in_params[3].type		= ACPI_TYPE_BUFFER;
217 	in_params[3].buffer.length 	= context->cap.length;
218 	in_params[3].buffer.pointer 	= context->cap.pointer;
219 
220 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
221 	if (ACPI_FAILURE(status))
222 		return status;
223 
224 	if (!output.length)
225 		return AE_NULL_OBJECT;
226 
227 	out_obj = output.pointer;
228 	if (out_obj->type != ACPI_TYPE_BUFFER
229 		|| out_obj->buffer.length != context->cap.length) {
230 		acpi_print_osc_error(handle, context,
231 			"_OSC evaluation returned wrong type");
232 		status = AE_TYPE;
233 		goto out_kfree;
234 	}
235 	/* Need to ignore the bit0 in result code */
236 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
237 	if (errors) {
238 		if (errors & OSC_REQUEST_ERROR)
239 			acpi_print_osc_error(handle, context,
240 				"_OSC request failed");
241 		if (errors & OSC_INVALID_UUID_ERROR)
242 			acpi_print_osc_error(handle, context,
243 				"_OSC invalid UUID");
244 		if (errors & OSC_INVALID_REVISION_ERROR)
245 			acpi_print_osc_error(handle, context,
246 				"_OSC invalid revision");
247 		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
248 			if (((u32 *)context->cap.pointer)[OSC_QUERY_DWORD]
249 			    & OSC_QUERY_ENABLE)
250 				goto out_success;
251 			status = AE_SUPPORT;
252 			goto out_kfree;
253 		}
254 		status = AE_ERROR;
255 		goto out_kfree;
256 	}
257 out_success:
258 	context->ret.length = out_obj->buffer.length;
259 	context->ret.pointer = kmemdup(out_obj->buffer.pointer,
260 				       context->ret.length, GFP_KERNEL);
261 	if (!context->ret.pointer) {
262 		status =  AE_NO_MEMORY;
263 		goto out_kfree;
264 	}
265 	status =  AE_OK;
266 
267 out_kfree:
268 	kfree(output.pointer);
269 	return status;
270 }
271 EXPORT_SYMBOL(acpi_run_osc);
272 
273 bool osc_sb_apei_support_acked;
274 
275 /*
276  * ACPI 6.0 Section 8.4.4.2 Idle State Coordination
277  * OSPM supports platform coordinated low power idle(LPI) states
278  */
279 bool osc_pc_lpi_support_confirmed;
280 EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
281 
282 /*
283  * ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
284  *   Starting with ACPI Specification 6.2, all _CPC registers can be in
285  *   PCC, System Memory, System IO, or Functional Fixed Hardware address
286  *   spaces. OSPM support for this more flexible register space scheme is
287  *   indicated by the “Flexible Address Space for CPPC Registers” _OSC bit.
288  *
289  * Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
290  * - PCC or Functional Fixed Hardware address space if defined
291  * - SystemMemory address space (NULL register) if not defined
292  */
293 bool osc_cpc_flexible_adr_space_confirmed;
294 EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
295 
296 /*
297  * ACPI 6.4 Operating System Capabilities for USB.
298  */
299 bool osc_sb_native_usb4_support_confirmed;
300 EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed);
301 
302 bool osc_sb_cppc2_support_acked;
303 
304 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
305 static void acpi_bus_osc_negotiate_platform_control(void)
306 {
307 	u32 capbuf[2], *capbuf_ret;
308 	struct acpi_osc_context context = {
309 		.uuid_str = sb_uuid_str,
310 		.rev = 1,
311 		.cap.length = 8,
312 		.cap.pointer = capbuf,
313 	};
314 	acpi_handle handle;
315 
316 	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
317 	capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
318 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR_AGGREGATOR))
319 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
320 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR))
321 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
322 
323 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
324 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PCLPI_SUPPORT;
325 	if (IS_ENABLED(CONFIG_ACPI_PRMT))
326 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PRM_SUPPORT;
327 	if (IS_ENABLED(CONFIG_ACPI_FFH))
328 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_FFH_OPR_SUPPORT;
329 
330 #ifdef CONFIG_ARM64
331 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
332 #endif
333 #ifdef CONFIG_X86
334 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
335 #endif
336 
337 #ifdef CONFIG_ACPI_CPPC_LIB
338 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
339 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
340 #endif
341 
342 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
343 
344 	if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
345 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
346 
347 	if (IS_ENABLED(CONFIG_USB4))
348 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_NATIVE_USB4_SUPPORT;
349 
350 	if (!ghes_disable)
351 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
352 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
353 		return;
354 
355 	if (ACPI_FAILURE(acpi_run_osc(handle, &context)))
356 		return;
357 
358 	capbuf_ret = context.ret.pointer;
359 	if (context.ret.length <= OSC_SUPPORT_DWORD) {
360 		kfree(context.ret.pointer);
361 		return;
362 	}
363 
364 	/*
365 	 * Now run _OSC again with query flag clear and with the caps
366 	 * supported by both the OS and the platform.
367 	 */
368 	capbuf[OSC_QUERY_DWORD] = 0;
369 	capbuf[OSC_SUPPORT_DWORD] = capbuf_ret[OSC_SUPPORT_DWORD];
370 	kfree(context.ret.pointer);
371 
372 	if (ACPI_FAILURE(acpi_run_osc(handle, &context)))
373 		return;
374 
375 	capbuf_ret = context.ret.pointer;
376 	if (context.ret.length > OSC_SUPPORT_DWORD) {
377 #ifdef CONFIG_ACPI_CPPC_LIB
378 		osc_sb_cppc2_support_acked = capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPCV2_SUPPORT;
379 #endif
380 
381 		osc_sb_apei_support_acked =
382 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
383 		osc_pc_lpi_support_confirmed =
384 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
385 		osc_sb_native_usb4_support_confirmed =
386 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
387 		osc_cpc_flexible_adr_space_confirmed =
388 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
389 	}
390 
391 	kfree(context.ret.pointer);
392 }
393 
394 /*
395  * Native control of USB4 capabilities. If any of the tunneling bits is
396  * set it means OS is in control and we use software based connection
397  * manager.
398  */
399 u32 osc_sb_native_usb4_control;
400 EXPORT_SYMBOL_GPL(osc_sb_native_usb4_control);
401 
402 static void acpi_bus_decode_usb_osc(const char *msg, u32 bits)
403 {
404 	pr_info("%s USB3%c DisplayPort%c PCIe%c XDomain%c\n", msg,
405 	       (bits & OSC_USB_USB3_TUNNELING) ? '+' : '-',
406 	       (bits & OSC_USB_DP_TUNNELING) ? '+' : '-',
407 	       (bits & OSC_USB_PCIE_TUNNELING) ? '+' : '-',
408 	       (bits & OSC_USB_XDOMAIN) ? '+' : '-');
409 }
410 
411 static u8 sb_usb_uuid_str[] = "23A0D13A-26AB-486C-9C5F-0FFA525A575A";
412 static void acpi_bus_osc_negotiate_usb_control(void)
413 {
414 	u32 capbuf[3];
415 	struct acpi_osc_context context = {
416 		.uuid_str = sb_usb_uuid_str,
417 		.rev = 1,
418 		.cap.length = sizeof(capbuf),
419 		.cap.pointer = capbuf,
420 	};
421 	acpi_handle handle;
422 	acpi_status status;
423 	u32 control;
424 
425 	if (!osc_sb_native_usb4_support_confirmed)
426 		return;
427 
428 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
429 		return;
430 
431 	control = OSC_USB_USB3_TUNNELING | OSC_USB_DP_TUNNELING |
432 		  OSC_USB_PCIE_TUNNELING | OSC_USB_XDOMAIN;
433 
434 	capbuf[OSC_QUERY_DWORD] = 0;
435 	capbuf[OSC_SUPPORT_DWORD] = 0;
436 	capbuf[OSC_CONTROL_DWORD] = control;
437 
438 	status = acpi_run_osc(handle, &context);
439 	if (ACPI_FAILURE(status))
440 		return;
441 
442 	if (context.ret.length != sizeof(capbuf)) {
443 		pr_info("USB4 _OSC: returned invalid length buffer\n");
444 		goto out_free;
445 	}
446 
447 	osc_sb_native_usb4_control =
448 		control &  acpi_osc_ctx_get_pci_control(&context);
449 
450 	acpi_bus_decode_usb_osc("USB4 _OSC: OS supports", control);
451 	acpi_bus_decode_usb_osc("USB4 _OSC: OS controls",
452 				osc_sb_native_usb4_control);
453 
454 out_free:
455 	kfree(context.ret.pointer);
456 }
457 
458 /* --------------------------------------------------------------------------
459                              Notification Handling
460    -------------------------------------------------------------------------- */
461 
462 /**
463  * acpi_bus_notify - Global system-level (0x00-0x7F) notifications handler
464  * @handle: Target ACPI object.
465  * @type: Notification type.
466  * @data: Ignored.
467  *
468  * This only handles notifications related to device hotplug.
469  */
470 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
471 {
472 	struct acpi_device *adev;
473 
474 	switch (type) {
475 	case ACPI_NOTIFY_BUS_CHECK:
476 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
477 		break;
478 
479 	case ACPI_NOTIFY_DEVICE_CHECK:
480 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
481 		break;
482 
483 	case ACPI_NOTIFY_DEVICE_WAKE:
484 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
485 		return;
486 
487 	case ACPI_NOTIFY_EJECT_REQUEST:
488 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
489 		break;
490 
491 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
492 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
493 		/* TBD: Exactly what does 'light' mean? */
494 		return;
495 
496 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
497 		acpi_handle_err(handle, "Device cannot be configured due "
498 				"to a frequency mismatch\n");
499 		return;
500 
501 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
502 		acpi_handle_err(handle, "Device cannot be configured due "
503 				"to a bus mode mismatch\n");
504 		return;
505 
506 	case ACPI_NOTIFY_POWER_FAULT:
507 		acpi_handle_err(handle, "Device has suffered a power fault\n");
508 		return;
509 
510 	default:
511 		acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
512 		return;
513 	}
514 
515 	adev = acpi_get_acpi_dev(handle);
516 
517 	if (adev && ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
518 		return;
519 
520 	acpi_put_acpi_dev(adev);
521 
522 	acpi_evaluate_ost(handle, type, ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
523 }
524 
525 static void acpi_notify_device(acpi_handle handle, u32 event, void *data)
526 {
527 	struct acpi_device *device = data;
528 	struct acpi_driver *acpi_drv = to_acpi_driver(device->dev.driver);
529 
530 	acpi_drv->ops.notify(device, event);
531 }
532 
533 static void acpi_notify_device_fixed(void *data)
534 {
535 	struct acpi_device *device = data;
536 
537 	/* Fixed hardware devices have no handles */
538 	acpi_notify_device(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
539 }
540 
541 static u32 acpi_device_fixed_event(void *data)
542 {
543 	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_notify_device_fixed, data);
544 	return ACPI_INTERRUPT_HANDLED;
545 }
546 
547 static int acpi_device_install_notify_handler(struct acpi_device *device,
548 					      struct acpi_driver *acpi_drv)
549 {
550 	acpi_status status;
551 
552 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
553 		status =
554 		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
555 						     acpi_device_fixed_event,
556 						     device);
557 	} else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON) {
558 		status =
559 		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
560 						     acpi_device_fixed_event,
561 						     device);
562 	} else {
563 		u32 type = acpi_drv->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS ?
564 				ACPI_ALL_NOTIFY : ACPI_DEVICE_NOTIFY;
565 
566 		status = acpi_install_notify_handler(device->handle, type,
567 						     acpi_notify_device,
568 						     device);
569 	}
570 
571 	if (ACPI_FAILURE(status))
572 		return -EINVAL;
573 	return 0;
574 }
575 
576 static void acpi_device_remove_notify_handler(struct acpi_device *device,
577 					      struct acpi_driver *acpi_drv)
578 {
579 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
580 		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
581 						acpi_device_fixed_event);
582 	} else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON) {
583 		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
584 						acpi_device_fixed_event);
585 	} else {
586 		u32 type = acpi_drv->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS ?
587 				ACPI_ALL_NOTIFY : ACPI_DEVICE_NOTIFY;
588 
589 		acpi_remove_notify_handler(device->handle, type,
590 					   acpi_notify_device);
591 	}
592 	acpi_os_wait_events_complete();
593 }
594 
595 /* Handle events targeting \_SB device (at present only graceful shutdown) */
596 
597 #define ACPI_SB_NOTIFY_SHUTDOWN_REQUEST 0x81
598 #define ACPI_SB_INDICATE_INTERVAL	10000
599 
600 static void sb_notify_work(struct work_struct *dummy)
601 {
602 	acpi_handle sb_handle;
603 
604 	orderly_poweroff(true);
605 
606 	/*
607 	 * After initiating graceful shutdown, the ACPI spec requires OSPM
608 	 * to evaluate _OST method once every 10seconds to indicate that
609 	 * the shutdown is in progress
610 	 */
611 	acpi_get_handle(NULL, "\\_SB", &sb_handle);
612 	while (1) {
613 		pr_info("Graceful shutdown in progress.\n");
614 		acpi_evaluate_ost(sb_handle, ACPI_OST_EC_OSPM_SHUTDOWN,
615 				ACPI_OST_SC_OS_SHUTDOWN_IN_PROGRESS, NULL);
616 		msleep(ACPI_SB_INDICATE_INTERVAL);
617 	}
618 }
619 
620 static void acpi_sb_notify(acpi_handle handle, u32 event, void *data)
621 {
622 	static DECLARE_WORK(acpi_sb_work, sb_notify_work);
623 
624 	if (event == ACPI_SB_NOTIFY_SHUTDOWN_REQUEST) {
625 		if (!work_busy(&acpi_sb_work))
626 			schedule_work(&acpi_sb_work);
627 	} else {
628 		pr_warn("event %x is not supported by \\_SB device\n", event);
629 	}
630 }
631 
632 static int __init acpi_setup_sb_notify_handler(void)
633 {
634 	acpi_handle sb_handle;
635 
636 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &sb_handle)))
637 		return -ENXIO;
638 
639 	if (ACPI_FAILURE(acpi_install_notify_handler(sb_handle, ACPI_DEVICE_NOTIFY,
640 						acpi_sb_notify, NULL)))
641 		return -EINVAL;
642 
643 	return 0;
644 }
645 
646 /* --------------------------------------------------------------------------
647                              Device Matching
648    -------------------------------------------------------------------------- */
649 
650 /**
651  * acpi_get_first_physical_node - Get first physical node of an ACPI device
652  * @adev:	ACPI device in question
653  *
654  * Return: First physical node of ACPI device @adev
655  */
656 struct device *acpi_get_first_physical_node(struct acpi_device *adev)
657 {
658 	struct mutex *physical_node_lock = &adev->physical_node_lock;
659 	struct device *phys_dev;
660 
661 	mutex_lock(physical_node_lock);
662 	if (list_empty(&adev->physical_node_list)) {
663 		phys_dev = NULL;
664 	} else {
665 		const struct acpi_device_physical_node *node;
666 
667 		node = list_first_entry(&adev->physical_node_list,
668 					struct acpi_device_physical_node, node);
669 
670 		phys_dev = node->dev;
671 	}
672 	mutex_unlock(physical_node_lock);
673 	return phys_dev;
674 }
675 EXPORT_SYMBOL_GPL(acpi_get_first_physical_node);
676 
677 static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
678 						      const struct device *dev)
679 {
680 	const struct device *phys_dev = acpi_get_first_physical_node(adev);
681 
682 	return phys_dev && phys_dev == dev ? adev : NULL;
683 }
684 
685 /**
686  * acpi_device_is_first_physical_node - Is given dev first physical node
687  * @adev: ACPI companion device
688  * @dev: Physical device to check
689  *
690  * Function checks if given @dev is the first physical devices attached to
691  * the ACPI companion device. This distinction is needed in some cases
692  * where the same companion device is shared between many physical devices.
693  *
694  * Note that the caller have to provide valid @adev pointer.
695  */
696 bool acpi_device_is_first_physical_node(struct acpi_device *adev,
697 					const struct device *dev)
698 {
699 	return !!acpi_primary_dev_companion(adev, dev);
700 }
701 
702 /*
703  * acpi_companion_match() - Can we match via ACPI companion device
704  * @dev: Device in question
705  *
706  * Check if the given device has an ACPI companion and if that companion has
707  * a valid list of PNP IDs, and if the device is the first (primary) physical
708  * device associated with it.  Return the companion pointer if that's the case
709  * or NULL otherwise.
710  *
711  * If multiple physical devices are attached to a single ACPI companion, we need
712  * to be careful.  The usage scenario for this kind of relationship is that all
713  * of the physical devices in question use resources provided by the ACPI
714  * companion.  A typical case is an MFD device where all the sub-devices share
715  * the parent's ACPI companion.  In such cases we can only allow the primary
716  * (first) physical device to be matched with the help of the companion's PNP
717  * IDs.
718  *
719  * Additional physical devices sharing the ACPI companion can still use
720  * resources available from it but they will be matched normally using functions
721  * provided by their bus types (and analogously for their modalias).
722  */
723 struct acpi_device *acpi_companion_match(const struct device *dev)
724 {
725 	struct acpi_device *adev;
726 
727 	adev = ACPI_COMPANION(dev);
728 	if (!adev)
729 		return NULL;
730 
731 	if (list_empty(&adev->pnp.ids))
732 		return NULL;
733 
734 	return acpi_primary_dev_companion(adev, dev);
735 }
736 
737 /**
738  * acpi_of_match_device - Match device object using the "compatible" property.
739  * @adev: ACPI device object to match.
740  * @of_match_table: List of device IDs to match against.
741  * @of_id: OF ID if matched
742  *
743  * If @dev has an ACPI companion which has ACPI_DT_NAMESPACE_HID in its list of
744  * identifiers and a _DSD object with the "compatible" property, use that
745  * property to match against the given list of identifiers.
746  */
747 static bool acpi_of_match_device(struct acpi_device *adev,
748 				 const struct of_device_id *of_match_table,
749 				 const struct of_device_id **of_id)
750 {
751 	const union acpi_object *of_compatible, *obj;
752 	int i, nval;
753 
754 	if (!adev)
755 		return false;
756 
757 	of_compatible = adev->data.of_compatible;
758 	if (!of_match_table || !of_compatible)
759 		return false;
760 
761 	if (of_compatible->type == ACPI_TYPE_PACKAGE) {
762 		nval = of_compatible->package.count;
763 		obj = of_compatible->package.elements;
764 	} else { /* Must be ACPI_TYPE_STRING. */
765 		nval = 1;
766 		obj = of_compatible;
767 	}
768 	/* Now we can look for the driver DT compatible strings */
769 	for (i = 0; i < nval; i++, obj++) {
770 		const struct of_device_id *id;
771 
772 		for (id = of_match_table; id->compatible[0]; id++)
773 			if (!strcasecmp(obj->string.pointer, id->compatible)) {
774 				if (of_id)
775 					*of_id = id;
776 				return true;
777 			}
778 	}
779 
780 	return false;
781 }
782 
783 static bool acpi_of_modalias(struct acpi_device *adev,
784 			     char *modalias, size_t len)
785 {
786 	const union acpi_object *of_compatible;
787 	const union acpi_object *obj;
788 	const char *str, *chr;
789 
790 	of_compatible = adev->data.of_compatible;
791 	if (!of_compatible)
792 		return false;
793 
794 	if (of_compatible->type == ACPI_TYPE_PACKAGE)
795 		obj = of_compatible->package.elements;
796 	else /* Must be ACPI_TYPE_STRING. */
797 		obj = of_compatible;
798 
799 	str = obj->string.pointer;
800 	chr = strchr(str, ',');
801 	strscpy(modalias, chr ? chr + 1 : str, len);
802 
803 	return true;
804 }
805 
806 /**
807  * acpi_set_modalias - Set modalias using "compatible" property or supplied ID
808  * @adev:	ACPI device object to match
809  * @default_id:	ID string to use as default if no compatible string found
810  * @modalias:   Pointer to buffer that modalias value will be copied into
811  * @len:	Length of modalias buffer
812  *
813  * This is a counterpart of of_alias_from_compatible() for struct acpi_device
814  * objects. If there is a compatible string for @adev, it will be copied to
815  * @modalias with the vendor prefix stripped; otherwise, @default_id will be
816  * used.
817  */
818 void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
819 		       char *modalias, size_t len)
820 {
821 	if (!acpi_of_modalias(adev, modalias, len))
822 		strscpy(modalias, default_id, len);
823 }
824 EXPORT_SYMBOL_GPL(acpi_set_modalias);
825 
826 static bool __acpi_match_device_cls(const struct acpi_device_id *id,
827 				    struct acpi_hardware_id *hwid)
828 {
829 	int i, msk, byte_shift;
830 	char buf[3];
831 
832 	if (!id->cls)
833 		return false;
834 
835 	/* Apply class-code bitmask, before checking each class-code byte */
836 	for (i = 1; i <= 3; i++) {
837 		byte_shift = 8 * (3 - i);
838 		msk = (id->cls_msk >> byte_shift) & 0xFF;
839 		if (!msk)
840 			continue;
841 
842 		sprintf(buf, "%02x", (id->cls >> byte_shift) & msk);
843 		if (strncmp(buf, &hwid->id[(i - 1) * 2], 2))
844 			return false;
845 	}
846 	return true;
847 }
848 
849 static bool __acpi_match_device(struct acpi_device *device,
850 				const struct acpi_device_id *acpi_ids,
851 				const struct of_device_id *of_ids,
852 				const struct acpi_device_id **acpi_id,
853 				const struct of_device_id **of_id)
854 {
855 	const struct acpi_device_id *id;
856 	struct acpi_hardware_id *hwid;
857 
858 	/*
859 	 * If the device is not present, it is unnecessary to load device
860 	 * driver for it.
861 	 */
862 	if (!device || !device->status.present)
863 		return false;
864 
865 	list_for_each_entry(hwid, &device->pnp.ids, list) {
866 		/* First, check the ACPI/PNP IDs provided by the caller. */
867 		if (acpi_ids) {
868 			for (id = acpi_ids; id->id[0] || id->cls; id++) {
869 				if (id->id[0] && !strcmp((char *)id->id, hwid->id))
870 					goto out_acpi_match;
871 				if (id->cls && __acpi_match_device_cls(id, hwid))
872 					goto out_acpi_match;
873 			}
874 		}
875 
876 		/*
877 		 * Next, check ACPI_DT_NAMESPACE_HID and try to match the
878 		 * "compatible" property if found.
879 		 */
880 		if (!strcmp(ACPI_DT_NAMESPACE_HID, hwid->id))
881 			return acpi_of_match_device(device, of_ids, of_id);
882 	}
883 	return false;
884 
885 out_acpi_match:
886 	if (acpi_id)
887 		*acpi_id = id;
888 	return true;
889 }
890 
891 /**
892  * acpi_match_device - Match a struct device against a given list of ACPI IDs
893  * @ids: Array of struct acpi_device_id object to match against.
894  * @dev: The device structure to match.
895  *
896  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
897  * object for that handle and use that object to match against a given list of
898  * device IDs.
899  *
900  * Return a pointer to the first matching ID on success or %NULL on failure.
901  */
902 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
903 					       const struct device *dev)
904 {
905 	const struct acpi_device_id *id = NULL;
906 
907 	__acpi_match_device(acpi_companion_match(dev), ids, NULL, &id, NULL);
908 	return id;
909 }
910 EXPORT_SYMBOL_GPL(acpi_match_device);
911 
912 static const void *acpi_of_device_get_match_data(const struct device *dev)
913 {
914 	struct acpi_device *adev = ACPI_COMPANION(dev);
915 	const struct of_device_id *match = NULL;
916 
917 	if (!acpi_of_match_device(adev, dev->driver->of_match_table, &match))
918 		return NULL;
919 
920 	return match->data;
921 }
922 
923 const void *acpi_device_get_match_data(const struct device *dev)
924 {
925 	const struct acpi_device_id *acpi_ids = dev->driver->acpi_match_table;
926 	const struct acpi_device_id *match;
927 
928 	if (!acpi_ids)
929 		return acpi_of_device_get_match_data(dev);
930 
931 	match = acpi_match_device(acpi_ids, dev);
932 	if (!match)
933 		return NULL;
934 
935 	return (const void *)match->driver_data;
936 }
937 EXPORT_SYMBOL_GPL(acpi_device_get_match_data);
938 
939 int acpi_match_device_ids(struct acpi_device *device,
940 			  const struct acpi_device_id *ids)
941 {
942 	return __acpi_match_device(device, ids, NULL, NULL, NULL) ? 0 : -ENOENT;
943 }
944 EXPORT_SYMBOL(acpi_match_device_ids);
945 
946 bool acpi_driver_match_device(struct device *dev,
947 			      const struct device_driver *drv)
948 {
949 	const struct acpi_device_id *acpi_ids = drv->acpi_match_table;
950 	const struct of_device_id *of_ids = drv->of_match_table;
951 
952 	if (!acpi_ids)
953 		return acpi_of_match_device(ACPI_COMPANION(dev), of_ids, NULL);
954 
955 	return __acpi_match_device(acpi_companion_match(dev), acpi_ids, of_ids, NULL, NULL);
956 }
957 EXPORT_SYMBOL_GPL(acpi_driver_match_device);
958 
959 /* --------------------------------------------------------------------------
960                               ACPI Driver Management
961    -------------------------------------------------------------------------- */
962 
963 /**
964  * acpi_bus_register_driver - register a driver with the ACPI bus
965  * @driver: driver being registered
966  *
967  * Registers a driver with the ACPI bus.  Searches the namespace for all
968  * devices that match the driver's criteria and binds.  Returns zero for
969  * success or a negative error status for failure.
970  */
971 int acpi_bus_register_driver(struct acpi_driver *driver)
972 {
973 	if (acpi_disabled)
974 		return -ENODEV;
975 	driver->drv.name = driver->name;
976 	driver->drv.bus = &acpi_bus_type;
977 	driver->drv.owner = driver->owner;
978 
979 	return driver_register(&driver->drv);
980 }
981 
982 EXPORT_SYMBOL(acpi_bus_register_driver);
983 
984 /**
985  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
986  * @driver: driver to unregister
987  *
988  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
989  * devices that match the driver's criteria and unbinds.
990  */
991 void acpi_bus_unregister_driver(struct acpi_driver *driver)
992 {
993 	driver_unregister(&driver->drv);
994 }
995 
996 EXPORT_SYMBOL(acpi_bus_unregister_driver);
997 
998 /* --------------------------------------------------------------------------
999                               ACPI Bus operations
1000    -------------------------------------------------------------------------- */
1001 
1002 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
1003 {
1004 	struct acpi_device *acpi_dev = to_acpi_device(dev);
1005 	struct acpi_driver *acpi_drv = to_acpi_driver(drv);
1006 
1007 	return acpi_dev->flags.match_driver
1008 		&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
1009 }
1010 
1011 static int acpi_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
1012 {
1013 	return __acpi_device_uevent_modalias(to_acpi_device(dev), env);
1014 }
1015 
1016 static int acpi_device_probe(struct device *dev)
1017 {
1018 	struct acpi_device *acpi_dev = to_acpi_device(dev);
1019 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
1020 	int ret;
1021 
1022 	if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
1023 		return -EINVAL;
1024 
1025 	if (!acpi_drv->ops.add)
1026 		return -ENOSYS;
1027 
1028 	ret = acpi_drv->ops.add(acpi_dev);
1029 	if (ret)
1030 		return ret;
1031 
1032 	pr_debug("Driver [%s] successfully bound to device [%s]\n",
1033 		 acpi_drv->name, acpi_dev->pnp.bus_id);
1034 
1035 	if (acpi_drv->ops.notify) {
1036 		ret = acpi_device_install_notify_handler(acpi_dev, acpi_drv);
1037 		if (ret) {
1038 			if (acpi_drv->ops.remove)
1039 				acpi_drv->ops.remove(acpi_dev);
1040 
1041 			acpi_dev->driver_data = NULL;
1042 			return ret;
1043 		}
1044 	}
1045 
1046 	pr_debug("Found driver [%s] for device [%s]\n", acpi_drv->name,
1047 		 acpi_dev->pnp.bus_id);
1048 
1049 	get_device(dev);
1050 	return 0;
1051 }
1052 
1053 static void acpi_device_remove(struct device *dev)
1054 {
1055 	struct acpi_device *acpi_dev = to_acpi_device(dev);
1056 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
1057 
1058 	if (acpi_drv->ops.notify)
1059 		acpi_device_remove_notify_handler(acpi_dev, acpi_drv);
1060 
1061 	if (acpi_drv->ops.remove)
1062 		acpi_drv->ops.remove(acpi_dev);
1063 
1064 	acpi_dev->driver_data = NULL;
1065 
1066 	put_device(dev);
1067 }
1068 
1069 struct bus_type acpi_bus_type = {
1070 	.name		= "acpi",
1071 	.match		= acpi_bus_match,
1072 	.probe		= acpi_device_probe,
1073 	.remove		= acpi_device_remove,
1074 	.uevent		= acpi_device_uevent,
1075 };
1076 
1077 int acpi_bus_for_each_dev(int (*fn)(struct device *, void *), void *data)
1078 {
1079 	return bus_for_each_dev(&acpi_bus_type, NULL, data, fn);
1080 }
1081 EXPORT_SYMBOL_GPL(acpi_bus_for_each_dev);
1082 
1083 struct acpi_dev_walk_context {
1084 	int (*fn)(struct acpi_device *, void *);
1085 	void *data;
1086 };
1087 
1088 static int acpi_dev_for_one_check(struct device *dev, void *context)
1089 {
1090 	struct acpi_dev_walk_context *adwc = context;
1091 
1092 	if (dev->bus != &acpi_bus_type)
1093 		return 0;
1094 
1095 	return adwc->fn(to_acpi_device(dev), adwc->data);
1096 }
1097 EXPORT_SYMBOL_GPL(acpi_dev_for_each_child);
1098 
1099 int acpi_dev_for_each_child(struct acpi_device *adev,
1100 			    int (*fn)(struct acpi_device *, void *), void *data)
1101 {
1102 	struct acpi_dev_walk_context adwc = {
1103 		.fn = fn,
1104 		.data = data,
1105 	};
1106 
1107 	return device_for_each_child(&adev->dev, &adwc, acpi_dev_for_one_check);
1108 }
1109 
1110 int acpi_dev_for_each_child_reverse(struct acpi_device *adev,
1111 				    int (*fn)(struct acpi_device *, void *),
1112 				    void *data)
1113 {
1114 	struct acpi_dev_walk_context adwc = {
1115 		.fn = fn,
1116 		.data = data,
1117 	};
1118 
1119 	return device_for_each_child_reverse(&adev->dev, &adwc, acpi_dev_for_one_check);
1120 }
1121 
1122 /* --------------------------------------------------------------------------
1123                              Initialization/Cleanup
1124    -------------------------------------------------------------------------- */
1125 
1126 static int __init acpi_bus_init_irq(void)
1127 {
1128 	acpi_status status;
1129 	char *message = NULL;
1130 
1131 
1132 	/*
1133 	 * Let the system know what interrupt model we are using by
1134 	 * evaluating the \_PIC object, if exists.
1135 	 */
1136 
1137 	switch (acpi_irq_model) {
1138 	case ACPI_IRQ_MODEL_PIC:
1139 		message = "PIC";
1140 		break;
1141 	case ACPI_IRQ_MODEL_IOAPIC:
1142 		message = "IOAPIC";
1143 		break;
1144 	case ACPI_IRQ_MODEL_IOSAPIC:
1145 		message = "IOSAPIC";
1146 		break;
1147 	case ACPI_IRQ_MODEL_GIC:
1148 		message = "GIC";
1149 		break;
1150 	case ACPI_IRQ_MODEL_PLATFORM:
1151 		message = "platform specific model";
1152 		break;
1153 	case ACPI_IRQ_MODEL_LPIC:
1154 		message = "LPIC";
1155 		break;
1156 	default:
1157 		pr_info("Unknown interrupt routing model\n");
1158 		return -ENODEV;
1159 	}
1160 
1161 	pr_info("Using %s for interrupt routing\n", message);
1162 
1163 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
1164 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
1165 		pr_info("_PIC evaluation failed: %s\n", acpi_format_exception(status));
1166 		return -ENODEV;
1167 	}
1168 
1169 	return 0;
1170 }
1171 
1172 /**
1173  * acpi_early_init - Initialize ACPICA and populate the ACPI namespace.
1174  *
1175  * The ACPI tables are accessible after this, but the handling of events has not
1176  * been initialized and the global lock is not available yet, so AML should not
1177  * be executed at this point.
1178  *
1179  * Doing this before switching the EFI runtime services to virtual mode allows
1180  * the EfiBootServices memory to be freed slightly earlier on boot.
1181  */
1182 void __init acpi_early_init(void)
1183 {
1184 	acpi_status status;
1185 
1186 	if (acpi_disabled)
1187 		return;
1188 
1189 	pr_info("Core revision %08x\n", ACPI_CA_VERSION);
1190 
1191 	/* enable workarounds, unless strict ACPI spec. compliance */
1192 	if (!acpi_strict)
1193 		acpi_gbl_enable_interpreter_slack = TRUE;
1194 
1195 	acpi_permanent_mmap = true;
1196 
1197 #ifdef CONFIG_X86
1198 	/*
1199 	 * If the machine falls into the DMI check table,
1200 	 * DSDT will be copied to memory.
1201 	 * Note that calling dmi_check_system() here on other architectures
1202 	 * would not be OK because only x86 initializes dmi early enough.
1203 	 * Thankfully only x86 systems need such quirks for now.
1204 	 */
1205 	dmi_check_system(dsdt_dmi_table);
1206 #endif
1207 
1208 	status = acpi_reallocate_root_table();
1209 	if (ACPI_FAILURE(status)) {
1210 		pr_err("Unable to reallocate ACPI tables\n");
1211 		goto error0;
1212 	}
1213 
1214 	status = acpi_initialize_subsystem();
1215 	if (ACPI_FAILURE(status)) {
1216 		pr_err("Unable to initialize the ACPI Interpreter\n");
1217 		goto error0;
1218 	}
1219 
1220 #ifdef CONFIG_X86
1221 	if (!acpi_ioapic) {
1222 		/* compatible (0) means level (3) */
1223 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
1224 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
1225 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
1226 		}
1227 		/* Set PIC-mode SCI trigger type */
1228 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
1229 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
1230 	} else {
1231 		/*
1232 		 * now that acpi_gbl_FADT is initialized,
1233 		 * update it with result from INT_SRC_OVR parsing
1234 		 */
1235 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
1236 	}
1237 #endif
1238 	return;
1239 
1240  error0:
1241 	disable_acpi();
1242 }
1243 
1244 /**
1245  * acpi_subsystem_init - Finalize the early initialization of ACPI.
1246  *
1247  * Switch over the platform to the ACPI mode (if possible).
1248  *
1249  * Doing this too early is generally unsafe, but at the same time it needs to be
1250  * done before all things that really depend on ACPI.  The right spot appears to
1251  * be before finalizing the EFI initialization.
1252  */
1253 void __init acpi_subsystem_init(void)
1254 {
1255 	acpi_status status;
1256 
1257 	if (acpi_disabled)
1258 		return;
1259 
1260 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
1261 	if (ACPI_FAILURE(status)) {
1262 		pr_err("Unable to enable ACPI\n");
1263 		disable_acpi();
1264 	} else {
1265 		/*
1266 		 * If the system is using ACPI then we can be reasonably
1267 		 * confident that any regulators are managed by the firmware
1268 		 * so tell the regulator core it has everything it needs to
1269 		 * know.
1270 		 */
1271 		regulator_has_full_constraints();
1272 	}
1273 }
1274 
1275 static acpi_status acpi_bus_table_handler(u32 event, void *table, void *context)
1276 {
1277 	if (event == ACPI_TABLE_EVENT_LOAD)
1278 		acpi_scan_table_notify();
1279 
1280 	return acpi_sysfs_table_handler(event, table, context);
1281 }
1282 
1283 static int __init acpi_bus_init(void)
1284 {
1285 	int result;
1286 	acpi_status status;
1287 
1288 	acpi_os_initialize1();
1289 
1290 	status = acpi_load_tables();
1291 	if (ACPI_FAILURE(status)) {
1292 		pr_err("Unable to load the System Description Tables\n");
1293 		goto error1;
1294 	}
1295 
1296 	/*
1297 	 * ACPI 2.0 requires the EC driver to be loaded and work before the EC
1298 	 * device is found in the namespace.
1299 	 *
1300 	 * This is accomplished by looking for the ECDT table and getting the EC
1301 	 * parameters out of that.
1302 	 *
1303 	 * Do that before calling acpi_initialize_objects() which may trigger EC
1304 	 * address space accesses.
1305 	 */
1306 	acpi_ec_ecdt_probe();
1307 
1308 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
1309 	if (ACPI_FAILURE(status)) {
1310 		pr_err("Unable to start the ACPI Interpreter\n");
1311 		goto error1;
1312 	}
1313 
1314 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
1315 	if (ACPI_FAILURE(status)) {
1316 		pr_err("Unable to initialize ACPI objects\n");
1317 		goto error1;
1318 	}
1319 
1320 	/* Set capability bits for _OSC under processor scope */
1321 	acpi_early_processor_osc();
1322 
1323 	/*
1324 	 * _OSC method may exist in module level code,
1325 	 * so it must be run after ACPI_FULL_INITIALIZATION
1326 	 */
1327 	acpi_bus_osc_negotiate_platform_control();
1328 	acpi_bus_osc_negotiate_usb_control();
1329 
1330 	/*
1331 	 * _PDC control method may load dynamic SSDT tables,
1332 	 * and we need to install the table handler before that.
1333 	 */
1334 	status = acpi_install_table_handler(acpi_bus_table_handler, NULL);
1335 
1336 	acpi_sysfs_init();
1337 
1338 	acpi_early_processor_set_pdc();
1339 
1340 	/*
1341 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
1342 	 * is necessary to enable it as early as possible.
1343 	 */
1344 	acpi_ec_dsdt_probe();
1345 
1346 	pr_info("Interpreter enabled\n");
1347 
1348 	/* Initialize sleep structures */
1349 	acpi_sleep_init();
1350 
1351 	/*
1352 	 * Get the system interrupt model and evaluate \_PIC.
1353 	 */
1354 	result = acpi_bus_init_irq();
1355 	if (result)
1356 		goto error1;
1357 
1358 	/*
1359 	 * Register the for all standard device notifications.
1360 	 */
1361 	status =
1362 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
1363 					&acpi_bus_notify, NULL);
1364 	if (ACPI_FAILURE(status)) {
1365 		pr_err("Unable to register for system notifications\n");
1366 		goto error1;
1367 	}
1368 
1369 	/*
1370 	 * Create the top ACPI proc directory
1371 	 */
1372 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
1373 
1374 	result = bus_register(&acpi_bus_type);
1375 	if (!result)
1376 		return 0;
1377 
1378 	/* Mimic structured exception handling */
1379       error1:
1380 	acpi_terminate();
1381 	return -ENODEV;
1382 }
1383 
1384 struct kobject *acpi_kobj;
1385 EXPORT_SYMBOL_GPL(acpi_kobj);
1386 
1387 static int __init acpi_init(void)
1388 {
1389 	int result;
1390 
1391 	if (acpi_disabled) {
1392 		pr_info("Interpreter disabled.\n");
1393 		return -ENODEV;
1394 	}
1395 
1396 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
1397 	if (!acpi_kobj)
1398 		pr_debug("%s: kset create error\n", __func__);
1399 
1400 	init_prmt();
1401 	acpi_init_pcc();
1402 	result = acpi_bus_init();
1403 	if (result) {
1404 		kobject_put(acpi_kobj);
1405 		disable_acpi();
1406 		return result;
1407 	}
1408 	acpi_init_ffh();
1409 
1410 	pci_mmcfg_late_init();
1411 	acpi_iort_init();
1412 	acpi_viot_early_init();
1413 	acpi_hest_init();
1414 	acpi_ghes_init();
1415 	acpi_scan_init();
1416 	acpi_ec_init();
1417 	acpi_debugfs_init();
1418 	acpi_sleep_proc_init();
1419 	acpi_wakeup_device_init();
1420 	acpi_debugger_init();
1421 	acpi_setup_sb_notify_handler();
1422 	acpi_viot_init();
1423 	acpi_agdi_init();
1424 	acpi_apmt_init();
1425 	return 0;
1426 }
1427 
1428 subsys_initcall(acpi_init);
1429