xref: /linux/drivers/acpi/bus.c (revision 2fe05e1139a555ae91f00a812cb9520e7d3022ab)
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  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
19  */
20 
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/ioport.h>
24 #include <linux/kernel.h>
25 #include <linux/list.h>
26 #include <linux/sched.h>
27 #include <linux/pm.h>
28 #include <linux/device.h>
29 #include <linux/proc_fs.h>
30 #include <linux/acpi.h>
31 #include <linux/slab.h>
32 #include <linux/regulator/machine.h>
33 #include <linux/workqueue.h>
34 #include <linux/reboot.h>
35 #include <linux/delay.h>
36 #ifdef CONFIG_X86
37 #include <asm/mpspec.h>
38 #endif
39 #include <linux/acpi_iort.h>
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 	if (acpi_device_always_present(device)) {
118 		acpi_set_device_status(device, ACPI_STA_DEFAULT);
119 		return 0;
120 	}
121 
122 	status = acpi_bus_get_status_handle(device->handle, &sta);
123 	if (ACPI_FAILURE(status))
124 		return -ENODEV;
125 
126 	acpi_set_device_status(device, sta);
127 
128 	if (device->status.functional && !device->status.present) {
129 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
130 		       "functional but not present;\n",
131 			device->pnp.bus_id, (u32)sta));
132 	}
133 
134 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
135 			  device->pnp.bus_id, (u32)sta));
136 	return 0;
137 }
138 EXPORT_SYMBOL(acpi_bus_get_status);
139 
140 void acpi_bus_private_data_handler(acpi_handle handle,
141 				   void *context)
142 {
143 	return;
144 }
145 EXPORT_SYMBOL(acpi_bus_private_data_handler);
146 
147 int acpi_bus_attach_private_data(acpi_handle handle, void *data)
148 {
149 	acpi_status status;
150 
151 	status = acpi_attach_data(handle,
152 			acpi_bus_private_data_handler, data);
153 	if (ACPI_FAILURE(status)) {
154 		acpi_handle_debug(handle, "Error attaching device data\n");
155 		return -ENODEV;
156 	}
157 
158 	return 0;
159 }
160 EXPORT_SYMBOL_GPL(acpi_bus_attach_private_data);
161 
162 int acpi_bus_get_private_data(acpi_handle handle, void **data)
163 {
164 	acpi_status status;
165 
166 	if (!*data)
167 		return -EINVAL;
168 
169 	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
170 	if (ACPI_FAILURE(status)) {
171 		acpi_handle_debug(handle, "No context for object\n");
172 		return -ENODEV;
173 	}
174 
175 	return 0;
176 }
177 EXPORT_SYMBOL_GPL(acpi_bus_get_private_data);
178 
179 void acpi_bus_detach_private_data(acpi_handle handle)
180 {
181 	acpi_detach_data(handle, acpi_bus_private_data_handler);
182 }
183 EXPORT_SYMBOL_GPL(acpi_bus_detach_private_data);
184 
185 static void acpi_print_osc_error(acpi_handle handle,
186 				 struct acpi_osc_context *context, char *error)
187 {
188 	int i;
189 
190 	acpi_handle_debug(handle, "(%s): %s\n", context->uuid_str, error);
191 
192 	pr_debug("_OSC request data:");
193 	for (i = 0; i < context->cap.length; i += sizeof(u32))
194 		pr_debug(" %x", *((u32 *)(context->cap.pointer + i)));
195 
196 	pr_debug("\n");
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 	guid_t guid;
206 	u32 errors;
207 	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
208 
209 	if (!context)
210 		return AE_ERROR;
211 	if (guid_parse(context->uuid_str, &guid))
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	= (u8 *)&guid;
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_DWORD]
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 
287 /*
288  * ACPI 6.0 Section 8.4.4.2 Idle State Coordination
289  * OSPM supports platform coordinated low power idle(LPI) states
290  */
291 bool osc_pc_lpi_support_confirmed;
292 EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
293 
294 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
295 static void acpi_bus_osc_support(void)
296 {
297 	u32 capbuf[2];
298 	struct acpi_osc_context context = {
299 		.uuid_str = sb_uuid_str,
300 		.rev = 1,
301 		.cap.length = 8,
302 		.cap.pointer = capbuf,
303 	};
304 	acpi_handle handle;
305 
306 	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
307 	capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
308 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR_AGGREGATOR))
309 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
310 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR))
311 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
312 
313 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
314 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PCLPI_SUPPORT;
315 
316 #ifdef CONFIG_X86
317 	if (boot_cpu_has(X86_FEATURE_HWP)) {
318 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
319 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
320 	}
321 #endif
322 
323 	if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
324 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
325 
326 	if (!ghes_disable)
327 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
328 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
329 		return;
330 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
331 		u32 *capbuf_ret = context.ret.pointer;
332 		if (context.ret.length > OSC_SUPPORT_DWORD) {
333 			osc_sb_apei_support_acked =
334 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
335 			osc_pc_lpi_support_confirmed =
336 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
337 		}
338 		kfree(context.ret.pointer);
339 	}
340 	/* do we need to check other returned cap? Sounds no */
341 }
342 
343 /* --------------------------------------------------------------------------
344                              Notification Handling
345    -------------------------------------------------------------------------- */
346 
347 /**
348  * acpi_bus_notify
349  * ---------------
350  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
351  */
352 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
353 {
354 	struct acpi_device *adev;
355 	struct acpi_driver *driver;
356 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
357 	bool hotplug_event = false;
358 
359 	switch (type) {
360 	case ACPI_NOTIFY_BUS_CHECK:
361 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
362 		hotplug_event = true;
363 		break;
364 
365 	case ACPI_NOTIFY_DEVICE_CHECK:
366 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
367 		hotplug_event = true;
368 		break;
369 
370 	case ACPI_NOTIFY_DEVICE_WAKE:
371 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
372 		break;
373 
374 	case ACPI_NOTIFY_EJECT_REQUEST:
375 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
376 		hotplug_event = true;
377 		break;
378 
379 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
380 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
381 		/* TBD: Exactly what does 'light' mean? */
382 		break;
383 
384 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
385 		acpi_handle_err(handle, "Device cannot be configured due "
386 				"to a frequency mismatch\n");
387 		break;
388 
389 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
390 		acpi_handle_err(handle, "Device cannot be configured due "
391 				"to a bus mode mismatch\n");
392 		break;
393 
394 	case ACPI_NOTIFY_POWER_FAULT:
395 		acpi_handle_err(handle, "Device has suffered a power fault\n");
396 		break;
397 
398 	default:
399 		acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
400 		break;
401 	}
402 
403 	adev = acpi_bus_get_acpi_device(handle);
404 	if (!adev)
405 		goto err;
406 
407 	driver = adev->driver;
408 	if (driver && driver->ops.notify &&
409 	    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
410 		driver->ops.notify(adev, type);
411 
412 	if (!hotplug_event) {
413 		acpi_bus_put_acpi_device(adev);
414 		return;
415 	}
416 
417 	if (ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
418 		return;
419 
420 	acpi_bus_put_acpi_device(adev);
421 
422  err:
423 	acpi_evaluate_ost(handle, type, ost_code, NULL);
424 }
425 
426 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
427 {
428 	struct acpi_device *device = data;
429 
430 	device->driver->ops.notify(device, event);
431 }
432 
433 static void acpi_device_notify_fixed(void *data)
434 {
435 	struct acpi_device *device = data;
436 
437 	/* Fixed hardware devices have no handles */
438 	acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
439 }
440 
441 static u32 acpi_device_fixed_event(void *data)
442 {
443 	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
444 	return ACPI_INTERRUPT_HANDLED;
445 }
446 
447 static int acpi_device_install_notify_handler(struct acpi_device *device)
448 {
449 	acpi_status status;
450 
451 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
452 		status =
453 		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
454 						     acpi_device_fixed_event,
455 						     device);
456 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
457 		status =
458 		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
459 						     acpi_device_fixed_event,
460 						     device);
461 	else
462 		status = acpi_install_notify_handler(device->handle,
463 						     ACPI_DEVICE_NOTIFY,
464 						     acpi_device_notify,
465 						     device);
466 
467 	if (ACPI_FAILURE(status))
468 		return -EINVAL;
469 	return 0;
470 }
471 
472 static void acpi_device_remove_notify_handler(struct acpi_device *device)
473 {
474 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
475 		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
476 						acpi_device_fixed_event);
477 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
478 		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
479 						acpi_device_fixed_event);
480 	else
481 		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
482 					   acpi_device_notify);
483 }
484 
485 /* Handle events targeting \_SB device (at present only graceful shutdown) */
486 
487 #define ACPI_SB_NOTIFY_SHUTDOWN_REQUEST 0x81
488 #define ACPI_SB_INDICATE_INTERVAL	10000
489 
490 static void sb_notify_work(struct work_struct *dummy)
491 {
492 	acpi_handle sb_handle;
493 
494 	orderly_poweroff(true);
495 
496 	/*
497 	 * After initiating graceful shutdown, the ACPI spec requires OSPM
498 	 * to evaluate _OST method once every 10seconds to indicate that
499 	 * the shutdown is in progress
500 	 */
501 	acpi_get_handle(NULL, "\\_SB", &sb_handle);
502 	while (1) {
503 		pr_info("Graceful shutdown in progress.\n");
504 		acpi_evaluate_ost(sb_handle, ACPI_OST_EC_OSPM_SHUTDOWN,
505 				ACPI_OST_SC_OS_SHUTDOWN_IN_PROGRESS, NULL);
506 		msleep(ACPI_SB_INDICATE_INTERVAL);
507 	}
508 }
509 
510 static void acpi_sb_notify(acpi_handle handle, u32 event, void *data)
511 {
512 	static DECLARE_WORK(acpi_sb_work, sb_notify_work);
513 
514 	if (event == ACPI_SB_NOTIFY_SHUTDOWN_REQUEST) {
515 		if (!work_busy(&acpi_sb_work))
516 			schedule_work(&acpi_sb_work);
517 	} else
518 		pr_warn("event %x is not supported by \\_SB device\n", event);
519 }
520 
521 static int __init acpi_setup_sb_notify_handler(void)
522 {
523 	acpi_handle sb_handle;
524 
525 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &sb_handle)))
526 		return -ENXIO;
527 
528 	if (ACPI_FAILURE(acpi_install_notify_handler(sb_handle, ACPI_DEVICE_NOTIFY,
529 						acpi_sb_notify, NULL)))
530 		return -EINVAL;
531 
532 	return 0;
533 }
534 
535 /* --------------------------------------------------------------------------
536                              Device Matching
537    -------------------------------------------------------------------------- */
538 
539 /**
540  * acpi_get_first_physical_node - Get first physical node of an ACPI device
541  * @adev:	ACPI device in question
542  *
543  * Return: First physical node of ACPI device @adev
544  */
545 struct device *acpi_get_first_physical_node(struct acpi_device *adev)
546 {
547 	struct mutex *physical_node_lock = &adev->physical_node_lock;
548 	struct device *phys_dev;
549 
550 	mutex_lock(physical_node_lock);
551 	if (list_empty(&adev->physical_node_list)) {
552 		phys_dev = NULL;
553 	} else {
554 		const struct acpi_device_physical_node *node;
555 
556 		node = list_first_entry(&adev->physical_node_list,
557 					struct acpi_device_physical_node, node);
558 
559 		phys_dev = node->dev;
560 	}
561 	mutex_unlock(physical_node_lock);
562 	return phys_dev;
563 }
564 
565 static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
566 						      const struct device *dev)
567 {
568 	const struct device *phys_dev = acpi_get_first_physical_node(adev);
569 
570 	return phys_dev && phys_dev == dev ? adev : NULL;
571 }
572 
573 /**
574  * acpi_device_is_first_physical_node - Is given dev first physical node
575  * @adev: ACPI companion device
576  * @dev: Physical device to check
577  *
578  * Function checks if given @dev is the first physical devices attached to
579  * the ACPI companion device. This distinction is needed in some cases
580  * where the same companion device is shared between many physical devices.
581  *
582  * Note that the caller have to provide valid @adev pointer.
583  */
584 bool acpi_device_is_first_physical_node(struct acpi_device *adev,
585 					const struct device *dev)
586 {
587 	return !!acpi_primary_dev_companion(adev, dev);
588 }
589 
590 /*
591  * acpi_companion_match() - Can we match via ACPI companion device
592  * @dev: Device in question
593  *
594  * Check if the given device has an ACPI companion and if that companion has
595  * a valid list of PNP IDs, and if the device is the first (primary) physical
596  * device associated with it.  Return the companion pointer if that's the case
597  * or NULL otherwise.
598  *
599  * If multiple physical devices are attached to a single ACPI companion, we need
600  * to be careful.  The usage scenario for this kind of relationship is that all
601  * of the physical devices in question use resources provided by the ACPI
602  * companion.  A typical case is an MFD device where all the sub-devices share
603  * the parent's ACPI companion.  In such cases we can only allow the primary
604  * (first) physical device to be matched with the help of the companion's PNP
605  * IDs.
606  *
607  * Additional physical devices sharing the ACPI companion can still use
608  * resources available from it but they will be matched normally using functions
609  * provided by their bus types (and analogously for their modalias).
610  */
611 struct acpi_device *acpi_companion_match(const struct device *dev)
612 {
613 	struct acpi_device *adev;
614 
615 	adev = ACPI_COMPANION(dev);
616 	if (!adev)
617 		return NULL;
618 
619 	if (list_empty(&adev->pnp.ids))
620 		return NULL;
621 
622 	return acpi_primary_dev_companion(adev, dev);
623 }
624 
625 /**
626  * acpi_of_match_device - Match device object using the "compatible" property.
627  * @adev: ACPI device object to match.
628  * @of_match_table: List of device IDs to match against.
629  *
630  * If @dev has an ACPI companion which has ACPI_DT_NAMESPACE_HID in its list of
631  * identifiers and a _DSD object with the "compatible" property, use that
632  * property to match against the given list of identifiers.
633  */
634 static bool acpi_of_match_device(struct acpi_device *adev,
635 				 const struct of_device_id *of_match_table)
636 {
637 	const union acpi_object *of_compatible, *obj;
638 	int i, nval;
639 
640 	if (!adev)
641 		return false;
642 
643 	of_compatible = adev->data.of_compatible;
644 	if (!of_match_table || !of_compatible)
645 		return false;
646 
647 	if (of_compatible->type == ACPI_TYPE_PACKAGE) {
648 		nval = of_compatible->package.count;
649 		obj = of_compatible->package.elements;
650 	} else { /* Must be ACPI_TYPE_STRING. */
651 		nval = 1;
652 		obj = of_compatible;
653 	}
654 	/* Now we can look for the driver DT compatible strings */
655 	for (i = 0; i < nval; i++, obj++) {
656 		const struct of_device_id *id;
657 
658 		for (id = of_match_table; id->compatible[0]; id++)
659 			if (!strcasecmp(obj->string.pointer, id->compatible))
660 				return true;
661 	}
662 
663 	return false;
664 }
665 
666 static bool acpi_of_modalias(struct acpi_device *adev,
667 			     char *modalias, size_t len)
668 {
669 	const union acpi_object *of_compatible;
670 	const union acpi_object *obj;
671 	const char *str, *chr;
672 
673 	of_compatible = adev->data.of_compatible;
674 	if (!of_compatible)
675 		return false;
676 
677 	if (of_compatible->type == ACPI_TYPE_PACKAGE)
678 		obj = of_compatible->package.elements;
679 	else /* Must be ACPI_TYPE_STRING. */
680 		obj = of_compatible;
681 
682 	str = obj->string.pointer;
683 	chr = strchr(str, ',');
684 	strlcpy(modalias, chr ? chr + 1 : str, len);
685 
686 	return true;
687 }
688 
689 /**
690  * acpi_set_modalias - Set modalias using "compatible" property or supplied ID
691  * @adev:	ACPI device object to match
692  * @default_id:	ID string to use as default if no compatible string found
693  * @modalias:   Pointer to buffer that modalias value will be copied into
694  * @len:	Length of modalias buffer
695  *
696  * This is a counterpart of of_modalias_node() for struct acpi_device objects.
697  * If there is a compatible string for @adev, it will be copied to @modalias
698  * with the vendor prefix stripped; otherwise, @default_id will be used.
699  */
700 void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
701 		       char *modalias, size_t len)
702 {
703 	if (!acpi_of_modalias(adev, modalias, len))
704 		strlcpy(modalias, default_id, len);
705 }
706 EXPORT_SYMBOL_GPL(acpi_set_modalias);
707 
708 static bool __acpi_match_device_cls(const struct acpi_device_id *id,
709 				    struct acpi_hardware_id *hwid)
710 {
711 	int i, msk, byte_shift;
712 	char buf[3];
713 
714 	if (!id->cls)
715 		return false;
716 
717 	/* Apply class-code bitmask, before checking each class-code byte */
718 	for (i = 1; i <= 3; i++) {
719 		byte_shift = 8 * (3 - i);
720 		msk = (id->cls_msk >> byte_shift) & 0xFF;
721 		if (!msk)
722 			continue;
723 
724 		sprintf(buf, "%02x", (id->cls >> byte_shift) & msk);
725 		if (strncmp(buf, &hwid->id[(i - 1) * 2], 2))
726 			return false;
727 	}
728 	return true;
729 }
730 
731 static const struct acpi_device_id *__acpi_match_device(
732 	struct acpi_device *device,
733 	const struct acpi_device_id *ids,
734 	const struct of_device_id *of_ids)
735 {
736 	const struct acpi_device_id *id;
737 	struct acpi_hardware_id *hwid;
738 
739 	/*
740 	 * If the device is not present, it is unnecessary to load device
741 	 * driver for it.
742 	 */
743 	if (!device || !device->status.present)
744 		return NULL;
745 
746 	list_for_each_entry(hwid, &device->pnp.ids, list) {
747 		/* First, check the ACPI/PNP IDs provided by the caller. */
748 		for (id = ids; id->id[0] || id->cls; id++) {
749 			if (id->id[0] && !strcmp((char *) id->id, hwid->id))
750 				return id;
751 			else if (id->cls && __acpi_match_device_cls(id, hwid))
752 				return id;
753 		}
754 
755 		/*
756 		 * Next, check ACPI_DT_NAMESPACE_HID and try to match the
757 		 * "compatible" property if found.
758 		 *
759 		 * The id returned by the below is not valid, but the only
760 		 * caller passing non-NULL of_ids here is only interested in
761 		 * whether or not the return value is NULL.
762 		 */
763 		if (!strcmp(ACPI_DT_NAMESPACE_HID, hwid->id)
764 		    && acpi_of_match_device(device, of_ids))
765 			return id;
766 	}
767 	return NULL;
768 }
769 
770 /**
771  * acpi_match_device - Match a struct device against a given list of ACPI IDs
772  * @ids: Array of struct acpi_device_id object to match against.
773  * @dev: The device structure to match.
774  *
775  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
776  * object for that handle and use that object to match against a given list of
777  * device IDs.
778  *
779  * Return a pointer to the first matching ID on success or %NULL on failure.
780  */
781 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
782 					       const struct device *dev)
783 {
784 	return __acpi_match_device(acpi_companion_match(dev), ids, NULL);
785 }
786 EXPORT_SYMBOL_GPL(acpi_match_device);
787 
788 int acpi_match_device_ids(struct acpi_device *device,
789 			  const struct acpi_device_id *ids)
790 {
791 	return __acpi_match_device(device, ids, NULL) ? 0 : -ENOENT;
792 }
793 EXPORT_SYMBOL(acpi_match_device_ids);
794 
795 bool acpi_driver_match_device(struct device *dev,
796 			      const struct device_driver *drv)
797 {
798 	if (!drv->acpi_match_table)
799 		return acpi_of_match_device(ACPI_COMPANION(dev),
800 					    drv->of_match_table);
801 
802 	return !!__acpi_match_device(acpi_companion_match(dev),
803 				     drv->acpi_match_table, drv->of_match_table);
804 }
805 EXPORT_SYMBOL_GPL(acpi_driver_match_device);
806 
807 /* --------------------------------------------------------------------------
808                               ACPI Driver Management
809    -------------------------------------------------------------------------- */
810 
811 /**
812  * acpi_bus_register_driver - register a driver with the ACPI bus
813  * @driver: driver being registered
814  *
815  * Registers a driver with the ACPI bus.  Searches the namespace for all
816  * devices that match the driver's criteria and binds.  Returns zero for
817  * success or a negative error status for failure.
818  */
819 int acpi_bus_register_driver(struct acpi_driver *driver)
820 {
821 	int ret;
822 
823 	if (acpi_disabled)
824 		return -ENODEV;
825 	driver->drv.name = driver->name;
826 	driver->drv.bus = &acpi_bus_type;
827 	driver->drv.owner = driver->owner;
828 
829 	ret = driver_register(&driver->drv);
830 	return ret;
831 }
832 
833 EXPORT_SYMBOL(acpi_bus_register_driver);
834 
835 /**
836  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
837  * @driver: driver to unregister
838  *
839  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
840  * devices that match the driver's criteria and unbinds.
841  */
842 void acpi_bus_unregister_driver(struct acpi_driver *driver)
843 {
844 	driver_unregister(&driver->drv);
845 }
846 
847 EXPORT_SYMBOL(acpi_bus_unregister_driver);
848 
849 /* --------------------------------------------------------------------------
850                               ACPI Bus operations
851    -------------------------------------------------------------------------- */
852 
853 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
854 {
855 	struct acpi_device *acpi_dev = to_acpi_device(dev);
856 	struct acpi_driver *acpi_drv = to_acpi_driver(drv);
857 
858 	return acpi_dev->flags.match_driver
859 		&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
860 }
861 
862 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
863 {
864 	return __acpi_device_uevent_modalias(to_acpi_device(dev), env);
865 }
866 
867 static int acpi_device_probe(struct device *dev)
868 {
869 	struct acpi_device *acpi_dev = to_acpi_device(dev);
870 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
871 	int ret;
872 
873 	if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
874 		return -EINVAL;
875 
876 	if (!acpi_drv->ops.add)
877 		return -ENOSYS;
878 
879 	ret = acpi_drv->ops.add(acpi_dev);
880 	if (ret)
881 		return ret;
882 
883 	acpi_dev->driver = acpi_drv;
884 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
885 			  "Driver [%s] successfully bound to device [%s]\n",
886 			  acpi_drv->name, acpi_dev->pnp.bus_id));
887 
888 	if (acpi_drv->ops.notify) {
889 		ret = acpi_device_install_notify_handler(acpi_dev);
890 		if (ret) {
891 			if (acpi_drv->ops.remove)
892 				acpi_drv->ops.remove(acpi_dev);
893 
894 			acpi_dev->driver = NULL;
895 			acpi_dev->driver_data = NULL;
896 			return ret;
897 		}
898 	}
899 
900 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
901 			  acpi_drv->name, acpi_dev->pnp.bus_id));
902 	get_device(dev);
903 	return 0;
904 }
905 
906 static int acpi_device_remove(struct device * dev)
907 {
908 	struct acpi_device *acpi_dev = to_acpi_device(dev);
909 	struct acpi_driver *acpi_drv = acpi_dev->driver;
910 
911 	if (acpi_drv) {
912 		if (acpi_drv->ops.notify)
913 			acpi_device_remove_notify_handler(acpi_dev);
914 		if (acpi_drv->ops.remove)
915 			acpi_drv->ops.remove(acpi_dev);
916 	}
917 	acpi_dev->driver = NULL;
918 	acpi_dev->driver_data = NULL;
919 
920 	put_device(dev);
921 	return 0;
922 }
923 
924 struct bus_type acpi_bus_type = {
925 	.name		= "acpi",
926 	.match		= acpi_bus_match,
927 	.probe		= acpi_device_probe,
928 	.remove		= acpi_device_remove,
929 	.uevent		= acpi_device_uevent,
930 };
931 
932 /* --------------------------------------------------------------------------
933                              Initialization/Cleanup
934    -------------------------------------------------------------------------- */
935 
936 static int __init acpi_bus_init_irq(void)
937 {
938 	acpi_status status;
939 	char *message = NULL;
940 
941 
942 	/*
943 	 * Let the system know what interrupt model we are using by
944 	 * evaluating the \_PIC object, if exists.
945 	 */
946 
947 	switch (acpi_irq_model) {
948 	case ACPI_IRQ_MODEL_PIC:
949 		message = "PIC";
950 		break;
951 	case ACPI_IRQ_MODEL_IOAPIC:
952 		message = "IOAPIC";
953 		break;
954 	case ACPI_IRQ_MODEL_IOSAPIC:
955 		message = "IOSAPIC";
956 		break;
957 	case ACPI_IRQ_MODEL_GIC:
958 		message = "GIC";
959 		break;
960 	case ACPI_IRQ_MODEL_PLATFORM:
961 		message = "platform specific model";
962 		break;
963 	default:
964 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
965 		return -ENODEV;
966 	}
967 
968 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
969 
970 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
971 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
972 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
973 		return -ENODEV;
974 	}
975 
976 	return 0;
977 }
978 
979 /**
980  * acpi_early_init - Initialize ACPICA and populate the ACPI namespace.
981  *
982  * The ACPI tables are accessible after this, but the handling of events has not
983  * been initialized and the global lock is not available yet, so AML should not
984  * be executed at this point.
985  *
986  * Doing this before switching the EFI runtime services to virtual mode allows
987  * the EfiBootServices memory to be freed slightly earlier on boot.
988  */
989 void __init acpi_early_init(void)
990 {
991 	acpi_status status;
992 
993 	if (acpi_disabled)
994 		return;
995 
996 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
997 
998 	/* It's safe to verify table checksums during late stage */
999 	acpi_gbl_verify_table_checksum = TRUE;
1000 
1001 	/* enable workarounds, unless strict ACPI spec. compliance */
1002 	if (!acpi_strict)
1003 		acpi_gbl_enable_interpreter_slack = TRUE;
1004 
1005 	acpi_permanent_mmap = true;
1006 
1007 	/*
1008 	 * If the machine falls into the DMI check table,
1009 	 * DSDT will be copied to memory
1010 	 */
1011 	dmi_check_system(dsdt_dmi_table);
1012 
1013 	status = acpi_reallocate_root_table();
1014 	if (ACPI_FAILURE(status)) {
1015 		printk(KERN_ERR PREFIX
1016 		       "Unable to reallocate ACPI tables\n");
1017 		goto error0;
1018 	}
1019 
1020 	status = acpi_initialize_subsystem();
1021 	if (ACPI_FAILURE(status)) {
1022 		printk(KERN_ERR PREFIX
1023 		       "Unable to initialize the ACPI Interpreter\n");
1024 		goto error0;
1025 	}
1026 
1027 	if (!acpi_gbl_parse_table_as_term_list &&
1028 	    acpi_gbl_group_module_level_code) {
1029 		status = acpi_load_tables();
1030 		if (ACPI_FAILURE(status)) {
1031 			printk(KERN_ERR PREFIX
1032 			       "Unable to load the System Description Tables\n");
1033 			goto error0;
1034 		}
1035 	}
1036 
1037 #ifdef CONFIG_X86
1038 	if (!acpi_ioapic) {
1039 		/* compatible (0) means level (3) */
1040 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
1041 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
1042 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
1043 		}
1044 		/* Set PIC-mode SCI trigger type */
1045 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
1046 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
1047 	} else {
1048 		/*
1049 		 * now that acpi_gbl_FADT is initialized,
1050 		 * update it with result from INT_SRC_OVR parsing
1051 		 */
1052 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
1053 	}
1054 #endif
1055 	return;
1056 
1057  error0:
1058 	disable_acpi();
1059 }
1060 
1061 /**
1062  * acpi_subsystem_init - Finalize the early initialization of ACPI.
1063  *
1064  * Switch over the platform to the ACPI mode (if possible).
1065  *
1066  * Doing this too early is generally unsafe, but at the same time it needs to be
1067  * done before all things that really depend on ACPI.  The right spot appears to
1068  * be before finalizing the EFI initialization.
1069  */
1070 void __init acpi_subsystem_init(void)
1071 {
1072 	acpi_status status;
1073 
1074 	if (acpi_disabled)
1075 		return;
1076 
1077 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
1078 	if (ACPI_FAILURE(status)) {
1079 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
1080 		disable_acpi();
1081 	} else {
1082 		/*
1083 		 * If the system is using ACPI then we can be reasonably
1084 		 * confident that any regulators are managed by the firmware
1085 		 * so tell the regulator core it has everything it needs to
1086 		 * know.
1087 		 */
1088 		regulator_has_full_constraints();
1089 	}
1090 }
1091 
1092 static acpi_status acpi_bus_table_handler(u32 event, void *table, void *context)
1093 {
1094 	acpi_scan_table_handler(event, table, context);
1095 
1096 	return acpi_sysfs_table_handler(event, table, context);
1097 }
1098 
1099 static int __init acpi_bus_init(void)
1100 {
1101 	int result;
1102 	acpi_status status;
1103 
1104 	acpi_os_initialize1();
1105 
1106 	/*
1107 	 * ACPI 2.0 requires the EC driver to be loaded and work before
1108 	 * the EC device is found in the namespace (i.e. before
1109 	 * acpi_load_tables() is called).
1110 	 *
1111 	 * This is accomplished by looking for the ECDT table, and getting
1112 	 * the EC parameters out of that.
1113 	 */
1114 	status = acpi_ec_ecdt_probe();
1115 	/* Ignore result. Not having an ECDT is not fatal. */
1116 
1117 	if (acpi_gbl_parse_table_as_term_list ||
1118 	    !acpi_gbl_group_module_level_code) {
1119 		status = acpi_load_tables();
1120 		if (ACPI_FAILURE(status)) {
1121 			printk(KERN_ERR PREFIX
1122 			       "Unable to load the System Description Tables\n");
1123 			goto error1;
1124 		}
1125 	}
1126 
1127 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
1128 	if (ACPI_FAILURE(status)) {
1129 		printk(KERN_ERR PREFIX
1130 		       "Unable to start the ACPI Interpreter\n");
1131 		goto error1;
1132 	}
1133 
1134 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
1135 	if (ACPI_FAILURE(status)) {
1136 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
1137 		goto error1;
1138 	}
1139 
1140 	/* Set capability bits for _OSC under processor scope */
1141 	acpi_early_processor_osc();
1142 
1143 	/*
1144 	 * _OSC method may exist in module level code,
1145 	 * so it must be run after ACPI_FULL_INITIALIZATION
1146 	 */
1147 	acpi_bus_osc_support();
1148 
1149 	/*
1150 	 * _PDC control method may load dynamic SSDT tables,
1151 	 * and we need to install the table handler before that.
1152 	 */
1153 	status = acpi_install_table_handler(acpi_bus_table_handler, NULL);
1154 
1155 	acpi_sysfs_init();
1156 
1157 	acpi_early_processor_set_pdc();
1158 
1159 	/*
1160 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
1161 	 * is necessary to enable it as early as possible.
1162 	 */
1163 	acpi_ec_dsdt_probe();
1164 
1165 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
1166 
1167 	/* Initialize sleep structures */
1168 	acpi_sleep_init();
1169 
1170 	/*
1171 	 * Get the system interrupt model and evaluate \_PIC.
1172 	 */
1173 	result = acpi_bus_init_irq();
1174 	if (result)
1175 		goto error1;
1176 
1177 	/*
1178 	 * Register the for all standard device notifications.
1179 	 */
1180 	status =
1181 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
1182 					&acpi_bus_notify, NULL);
1183 	if (ACPI_FAILURE(status)) {
1184 		printk(KERN_ERR PREFIX
1185 		       "Unable to register for device notifications\n");
1186 		goto error1;
1187 	}
1188 
1189 	/*
1190 	 * Create the top ACPI proc directory
1191 	 */
1192 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
1193 
1194 	result = bus_register(&acpi_bus_type);
1195 	if (!result)
1196 		return 0;
1197 
1198 	/* Mimic structured exception handling */
1199       error1:
1200 	acpi_terminate();
1201 	return -ENODEV;
1202 }
1203 
1204 struct kobject *acpi_kobj;
1205 EXPORT_SYMBOL_GPL(acpi_kobj);
1206 
1207 static int __init acpi_init(void)
1208 {
1209 	int result;
1210 
1211 	if (acpi_disabled) {
1212 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
1213 		return -ENODEV;
1214 	}
1215 
1216 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
1217 	if (!acpi_kobj) {
1218 		printk(KERN_WARNING "%s: kset create error\n", __func__);
1219 		acpi_kobj = NULL;
1220 	}
1221 
1222 	init_acpi_device_notify();
1223 	result = acpi_bus_init();
1224 	if (result) {
1225 		disable_acpi();
1226 		return result;
1227 	}
1228 
1229 	pci_mmcfg_late_init();
1230 	acpi_iort_init();
1231 	acpi_scan_init();
1232 	acpi_ec_init();
1233 	acpi_debugfs_init();
1234 	acpi_sleep_proc_init();
1235 	acpi_wakeup_device_init();
1236 	acpi_debugger_init();
1237 	acpi_setup_sb_notify_handler();
1238 	return 0;
1239 }
1240 
1241 subsys_initcall(acpi_init);
1242