xref: /openbmc/linux/drivers/acpi/bus.c (revision 788b041a)
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 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/ioport.h>
11 #include <linux/kernel.h>
12 #include <linux/list.h>
13 #include <linux/sched.h>
14 #include <linux/pm.h>
15 #include <linux/device.h>
16 #include <linux/proc_fs.h>
17 #include <linux/acpi.h>
18 #include <linux/slab.h>
19 #include <linux/regulator/machine.h>
20 #include <linux/workqueue.h>
21 #include <linux/reboot.h>
22 #include <linux/delay.h>
23 #ifdef CONFIG_X86
24 #include <asm/mpspec.h>
25 #include <linux/dmi.h>
26 #endif
27 #include <linux/acpi_iort.h>
28 #include <linux/pci.h>
29 #include <acpi/apei.h>
30 #include <linux/suspend.h>
31 
32 #include "internal.h"
33 
34 #define _COMPONENT		ACPI_BUS_COMPONENT
35 ACPI_MODULE_NAME("bus");
36 
37 struct acpi_device *acpi_root;
38 struct proc_dir_entry *acpi_root_dir;
39 EXPORT_SYMBOL(acpi_root_dir);
40 
41 #ifdef CONFIG_X86
42 #ifdef CONFIG_ACPI_CUSTOM_DSDT
43 static inline int set_copy_dsdt(const struct dmi_system_id *id)
44 {
45 	return 0;
46 }
47 #else
48 static int set_copy_dsdt(const struct dmi_system_id *id)
49 {
50 	printk(KERN_NOTICE "%s detected - "
51 		"force copy of DSDT to local memory\n", id->ident);
52 	acpi_gbl_copy_dsdt_locally = 1;
53 	return 0;
54 }
55 #endif
56 
57 static const struct dmi_system_id dsdt_dmi_table[] __initconst = {
58 	/*
59 	 * Invoke DSDT corruption work-around on all Toshiba Satellite.
60 	 * https://bugzilla.kernel.org/show_bug.cgi?id=14679
61 	 */
62 	{
63 	 .callback = set_copy_dsdt,
64 	 .ident = "TOSHIBA Satellite",
65 	 .matches = {
66 		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
67 		DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
68 		},
69 	},
70 	{}
71 };
72 #endif
73 
74 /* --------------------------------------------------------------------------
75                                 Device Management
76    -------------------------------------------------------------------------- */
77 
78 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
79 				       unsigned long long *sta)
80 {
81 	acpi_status status;
82 
83 	status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
84 	if (ACPI_SUCCESS(status))
85 		return AE_OK;
86 
87 	if (status == AE_NOT_FOUND) {
88 		*sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
89 		       ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
90 		return AE_OK;
91 	}
92 	return status;
93 }
94 EXPORT_SYMBOL_GPL(acpi_bus_get_status_handle);
95 
96 int acpi_bus_get_status(struct acpi_device *device)
97 {
98 	acpi_status status;
99 	unsigned long long sta;
100 
101 	if (acpi_device_always_present(device)) {
102 		acpi_set_device_status(device, ACPI_STA_DEFAULT);
103 		return 0;
104 	}
105 
106 	/* Battery devices must have their deps met before calling _STA */
107 	if (acpi_device_is_battery(device) && device->dep_unmet) {
108 		acpi_set_device_status(device, 0);
109 		return 0;
110 	}
111 
112 	status = acpi_bus_get_status_handle(device->handle, &sta);
113 	if (ACPI_FAILURE(status))
114 		return -ENODEV;
115 
116 	acpi_set_device_status(device, sta);
117 
118 	if (device->status.functional && !device->status.present) {
119 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
120 		       "functional but not present;\n",
121 			device->pnp.bus_id, (u32)sta));
122 	}
123 
124 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
125 			  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 	if (status != AE_OK)
270 		context->ret.pointer = NULL;
271 	return status;
272 }
273 EXPORT_SYMBOL(acpi_run_osc);
274 
275 bool osc_sb_apei_support_acked;
276 
277 /*
278  * ACPI 6.0 Section 8.4.4.2 Idle State Coordination
279  * OSPM supports platform coordinated low power idle(LPI) states
280  */
281 bool osc_pc_lpi_support_confirmed;
282 EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
283 
284 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
285 static void acpi_bus_osc_support(void)
286 {
287 	u32 capbuf[2];
288 	struct acpi_osc_context context = {
289 		.uuid_str = sb_uuid_str,
290 		.rev = 1,
291 		.cap.length = 8,
292 		.cap.pointer = capbuf,
293 	};
294 	acpi_handle handle;
295 
296 	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
297 	capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
298 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR_AGGREGATOR))
299 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
300 	if (IS_ENABLED(CONFIG_ACPI_PROCESSOR))
301 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
302 
303 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
304 	capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PCLPI_SUPPORT;
305 
306 #ifdef CONFIG_X86
307 	if (boot_cpu_has(X86_FEATURE_HWP)) {
308 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
309 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
310 	}
311 #endif
312 
313 	if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
314 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
315 
316 	if (!ghes_disable)
317 		capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
318 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
319 		return;
320 	if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
321 		u32 *capbuf_ret = context.ret.pointer;
322 		if (context.ret.length > OSC_SUPPORT_DWORD) {
323 			osc_sb_apei_support_acked =
324 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
325 			osc_pc_lpi_support_confirmed =
326 				capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
327 		}
328 		kfree(context.ret.pointer);
329 	}
330 	/* do we need to check other returned cap? Sounds no */
331 }
332 
333 /* --------------------------------------------------------------------------
334                              Notification Handling
335    -------------------------------------------------------------------------- */
336 
337 /**
338  * acpi_bus_notify
339  * ---------------
340  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
341  */
342 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
343 {
344 	struct acpi_device *adev;
345 	struct acpi_driver *driver;
346 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
347 	bool hotplug_event = false;
348 
349 	switch (type) {
350 	case ACPI_NOTIFY_BUS_CHECK:
351 		acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
352 		hotplug_event = true;
353 		break;
354 
355 	case ACPI_NOTIFY_DEVICE_CHECK:
356 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
357 		hotplug_event = true;
358 		break;
359 
360 	case ACPI_NOTIFY_DEVICE_WAKE:
361 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
362 		break;
363 
364 	case ACPI_NOTIFY_EJECT_REQUEST:
365 		acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
366 		hotplug_event = true;
367 		break;
368 
369 	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
370 		acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
371 		/* TBD: Exactly what does 'light' mean? */
372 		break;
373 
374 	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
375 		acpi_handle_err(handle, "Device cannot be configured due "
376 				"to a frequency mismatch\n");
377 		break;
378 
379 	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
380 		acpi_handle_err(handle, "Device cannot be configured due "
381 				"to a bus mode mismatch\n");
382 		break;
383 
384 	case ACPI_NOTIFY_POWER_FAULT:
385 		acpi_handle_err(handle, "Device has suffered a power fault\n");
386 		break;
387 
388 	default:
389 		acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
390 		break;
391 	}
392 
393 	adev = acpi_bus_get_acpi_device(handle);
394 	if (!adev)
395 		goto err;
396 
397 	driver = adev->driver;
398 	if (driver && driver->ops.notify &&
399 	    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
400 		driver->ops.notify(adev, type);
401 
402 	if (!hotplug_event) {
403 		acpi_bus_put_acpi_device(adev);
404 		return;
405 	}
406 
407 	if (ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
408 		return;
409 
410 	acpi_bus_put_acpi_device(adev);
411 
412  err:
413 	acpi_evaluate_ost(handle, type, ost_code, NULL);
414 }
415 
416 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
417 {
418 	struct acpi_device *device = data;
419 
420 	device->driver->ops.notify(device, event);
421 }
422 
423 static void acpi_device_notify_fixed(void *data)
424 {
425 	struct acpi_device *device = data;
426 
427 	/* Fixed hardware devices have no handles */
428 	acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
429 }
430 
431 static u32 acpi_device_fixed_event(void *data)
432 {
433 	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
434 	return ACPI_INTERRUPT_HANDLED;
435 }
436 
437 static int acpi_device_install_notify_handler(struct acpi_device *device)
438 {
439 	acpi_status status;
440 
441 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
442 		status =
443 		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
444 						     acpi_device_fixed_event,
445 						     device);
446 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
447 		status =
448 		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
449 						     acpi_device_fixed_event,
450 						     device);
451 	else
452 		status = acpi_install_notify_handler(device->handle,
453 						     ACPI_DEVICE_NOTIFY,
454 						     acpi_device_notify,
455 						     device);
456 
457 	if (ACPI_FAILURE(status))
458 		return -EINVAL;
459 	return 0;
460 }
461 
462 static void acpi_device_remove_notify_handler(struct acpi_device *device)
463 {
464 	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
465 		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
466 						acpi_device_fixed_event);
467 	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
468 		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
469 						acpi_device_fixed_event);
470 	else
471 		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
472 					   acpi_device_notify);
473 }
474 
475 /* Handle events targeting \_SB device (at present only graceful shutdown) */
476 
477 #define ACPI_SB_NOTIFY_SHUTDOWN_REQUEST 0x81
478 #define ACPI_SB_INDICATE_INTERVAL	10000
479 
480 static void sb_notify_work(struct work_struct *dummy)
481 {
482 	acpi_handle sb_handle;
483 
484 	orderly_poweroff(true);
485 
486 	/*
487 	 * After initiating graceful shutdown, the ACPI spec requires OSPM
488 	 * to evaluate _OST method once every 10seconds to indicate that
489 	 * the shutdown is in progress
490 	 */
491 	acpi_get_handle(NULL, "\\_SB", &sb_handle);
492 	while (1) {
493 		pr_info("Graceful shutdown in progress.\n");
494 		acpi_evaluate_ost(sb_handle, ACPI_OST_EC_OSPM_SHUTDOWN,
495 				ACPI_OST_SC_OS_SHUTDOWN_IN_PROGRESS, NULL);
496 		msleep(ACPI_SB_INDICATE_INTERVAL);
497 	}
498 }
499 
500 static void acpi_sb_notify(acpi_handle handle, u32 event, void *data)
501 {
502 	static DECLARE_WORK(acpi_sb_work, sb_notify_work);
503 
504 	if (event == ACPI_SB_NOTIFY_SHUTDOWN_REQUEST) {
505 		if (!work_busy(&acpi_sb_work))
506 			schedule_work(&acpi_sb_work);
507 	} else
508 		pr_warn("event %x is not supported by \\_SB device\n", event);
509 }
510 
511 static int __init acpi_setup_sb_notify_handler(void)
512 {
513 	acpi_handle sb_handle;
514 
515 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &sb_handle)))
516 		return -ENXIO;
517 
518 	if (ACPI_FAILURE(acpi_install_notify_handler(sb_handle, ACPI_DEVICE_NOTIFY,
519 						acpi_sb_notify, NULL)))
520 		return -EINVAL;
521 
522 	return 0;
523 }
524 
525 /* --------------------------------------------------------------------------
526                              Device Matching
527    -------------------------------------------------------------------------- */
528 
529 /**
530  * acpi_get_first_physical_node - Get first physical node of an ACPI device
531  * @adev:	ACPI device in question
532  *
533  * Return: First physical node of ACPI device @adev
534  */
535 struct device *acpi_get_first_physical_node(struct acpi_device *adev)
536 {
537 	struct mutex *physical_node_lock = &adev->physical_node_lock;
538 	struct device *phys_dev;
539 
540 	mutex_lock(physical_node_lock);
541 	if (list_empty(&adev->physical_node_list)) {
542 		phys_dev = NULL;
543 	} else {
544 		const struct acpi_device_physical_node *node;
545 
546 		node = list_first_entry(&adev->physical_node_list,
547 					struct acpi_device_physical_node, node);
548 
549 		phys_dev = node->dev;
550 	}
551 	mutex_unlock(physical_node_lock);
552 	return phys_dev;
553 }
554 
555 static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
556 						      const struct device *dev)
557 {
558 	const struct device *phys_dev = acpi_get_first_physical_node(adev);
559 
560 	return phys_dev && phys_dev == dev ? adev : NULL;
561 }
562 
563 /**
564  * acpi_device_is_first_physical_node - Is given dev first physical node
565  * @adev: ACPI companion device
566  * @dev: Physical device to check
567  *
568  * Function checks if given @dev is the first physical devices attached to
569  * the ACPI companion device. This distinction is needed in some cases
570  * where the same companion device is shared between many physical devices.
571  *
572  * Note that the caller have to provide valid @adev pointer.
573  */
574 bool acpi_device_is_first_physical_node(struct acpi_device *adev,
575 					const struct device *dev)
576 {
577 	return !!acpi_primary_dev_companion(adev, dev);
578 }
579 
580 /*
581  * acpi_companion_match() - Can we match via ACPI companion device
582  * @dev: Device in question
583  *
584  * Check if the given device has an ACPI companion and if that companion has
585  * a valid list of PNP IDs, and if the device is the first (primary) physical
586  * device associated with it.  Return the companion pointer if that's the case
587  * or NULL otherwise.
588  *
589  * If multiple physical devices are attached to a single ACPI companion, we need
590  * to be careful.  The usage scenario for this kind of relationship is that all
591  * of the physical devices in question use resources provided by the ACPI
592  * companion.  A typical case is an MFD device where all the sub-devices share
593  * the parent's ACPI companion.  In such cases we can only allow the primary
594  * (first) physical device to be matched with the help of the companion's PNP
595  * IDs.
596  *
597  * Additional physical devices sharing the ACPI companion can still use
598  * resources available from it but they will be matched normally using functions
599  * provided by their bus types (and analogously for their modalias).
600  */
601 struct acpi_device *acpi_companion_match(const struct device *dev)
602 {
603 	struct acpi_device *adev;
604 
605 	adev = ACPI_COMPANION(dev);
606 	if (!adev)
607 		return NULL;
608 
609 	if (list_empty(&adev->pnp.ids))
610 		return NULL;
611 
612 	return acpi_primary_dev_companion(adev, dev);
613 }
614 
615 /**
616  * acpi_of_match_device - Match device object using the "compatible" property.
617  * @adev: ACPI device object to match.
618  * @of_match_table: List of device IDs to match against.
619  * @of_id: OF ID if matched
620  *
621  * If @dev has an ACPI companion which has ACPI_DT_NAMESPACE_HID in its list of
622  * identifiers and a _DSD object with the "compatible" property, use that
623  * property to match against the given list of identifiers.
624  */
625 static bool acpi_of_match_device(struct acpi_device *adev,
626 				 const struct of_device_id *of_match_table,
627 				 const struct of_device_id **of_id)
628 {
629 	const union acpi_object *of_compatible, *obj;
630 	int i, nval;
631 
632 	if (!adev)
633 		return false;
634 
635 	of_compatible = adev->data.of_compatible;
636 	if (!of_match_table || !of_compatible)
637 		return false;
638 
639 	if (of_compatible->type == ACPI_TYPE_PACKAGE) {
640 		nval = of_compatible->package.count;
641 		obj = of_compatible->package.elements;
642 	} else { /* Must be ACPI_TYPE_STRING. */
643 		nval = 1;
644 		obj = of_compatible;
645 	}
646 	/* Now we can look for the driver DT compatible strings */
647 	for (i = 0; i < nval; i++, obj++) {
648 		const struct of_device_id *id;
649 
650 		for (id = of_match_table; id->compatible[0]; id++)
651 			if (!strcasecmp(obj->string.pointer, id->compatible)) {
652 				if (of_id)
653 					*of_id = id;
654 				return true;
655 			}
656 	}
657 
658 	return false;
659 }
660 
661 static bool acpi_of_modalias(struct acpi_device *adev,
662 			     char *modalias, size_t len)
663 {
664 	const union acpi_object *of_compatible;
665 	const union acpi_object *obj;
666 	const char *str, *chr;
667 
668 	of_compatible = adev->data.of_compatible;
669 	if (!of_compatible)
670 		return false;
671 
672 	if (of_compatible->type == ACPI_TYPE_PACKAGE)
673 		obj = of_compatible->package.elements;
674 	else /* Must be ACPI_TYPE_STRING. */
675 		obj = of_compatible;
676 
677 	str = obj->string.pointer;
678 	chr = strchr(str, ',');
679 	strlcpy(modalias, chr ? chr + 1 : str, len);
680 
681 	return true;
682 }
683 
684 /**
685  * acpi_set_modalias - Set modalias using "compatible" property or supplied ID
686  * @adev:	ACPI device object to match
687  * @default_id:	ID string to use as default if no compatible string found
688  * @modalias:   Pointer to buffer that modalias value will be copied into
689  * @len:	Length of modalias buffer
690  *
691  * This is a counterpart of of_modalias_node() for struct acpi_device objects.
692  * If there is a compatible string for @adev, it will be copied to @modalias
693  * with the vendor prefix stripped; otherwise, @default_id will be used.
694  */
695 void acpi_set_modalias(struct acpi_device *adev, const char *default_id,
696 		       char *modalias, size_t len)
697 {
698 	if (!acpi_of_modalias(adev, modalias, len))
699 		strlcpy(modalias, default_id, len);
700 }
701 EXPORT_SYMBOL_GPL(acpi_set_modalias);
702 
703 static bool __acpi_match_device_cls(const struct acpi_device_id *id,
704 				    struct acpi_hardware_id *hwid)
705 {
706 	int i, msk, byte_shift;
707 	char buf[3];
708 
709 	if (!id->cls)
710 		return false;
711 
712 	/* Apply class-code bitmask, before checking each class-code byte */
713 	for (i = 1; i <= 3; i++) {
714 		byte_shift = 8 * (3 - i);
715 		msk = (id->cls_msk >> byte_shift) & 0xFF;
716 		if (!msk)
717 			continue;
718 
719 		sprintf(buf, "%02x", (id->cls >> byte_shift) & msk);
720 		if (strncmp(buf, &hwid->id[(i - 1) * 2], 2))
721 			return false;
722 	}
723 	return true;
724 }
725 
726 static bool __acpi_match_device(struct acpi_device *device,
727 				const struct acpi_device_id *acpi_ids,
728 				const struct of_device_id *of_ids,
729 				const struct acpi_device_id **acpi_id,
730 				const struct of_device_id **of_id)
731 {
732 	const struct acpi_device_id *id;
733 	struct acpi_hardware_id *hwid;
734 
735 	/*
736 	 * If the device is not present, it is unnecessary to load device
737 	 * driver for it.
738 	 */
739 	if (!device || !device->status.present)
740 		return false;
741 
742 	list_for_each_entry(hwid, &device->pnp.ids, list) {
743 		/* First, check the ACPI/PNP IDs provided by the caller. */
744 		if (acpi_ids) {
745 			for (id = acpi_ids; id->id[0] || id->cls; id++) {
746 				if (id->id[0] && !strcmp((char *)id->id, hwid->id))
747 					goto out_acpi_match;
748 				if (id->cls && __acpi_match_device_cls(id, hwid))
749 					goto out_acpi_match;
750 			}
751 		}
752 
753 		/*
754 		 * Next, check ACPI_DT_NAMESPACE_HID and try to match the
755 		 * "compatible" property if found.
756 		 */
757 		if (!strcmp(ACPI_DT_NAMESPACE_HID, hwid->id))
758 			return acpi_of_match_device(device, of_ids, of_id);
759 	}
760 	return false;
761 
762 out_acpi_match:
763 	if (acpi_id)
764 		*acpi_id = id;
765 	return true;
766 }
767 
768 /**
769  * acpi_match_device - Match a struct device against a given list of ACPI IDs
770  * @ids: Array of struct acpi_device_id object to match against.
771  * @dev: The device structure to match.
772  *
773  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
774  * object for that handle and use that object to match against a given list of
775  * device IDs.
776  *
777  * Return a pointer to the first matching ID on success or %NULL on failure.
778  */
779 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
780 					       const struct device *dev)
781 {
782 	const struct acpi_device_id *id = NULL;
783 
784 	__acpi_match_device(acpi_companion_match(dev), ids, NULL, &id, NULL);
785 	return id;
786 }
787 EXPORT_SYMBOL_GPL(acpi_match_device);
788 
789 static const void *acpi_of_device_get_match_data(const struct device *dev)
790 {
791 	struct acpi_device *adev = ACPI_COMPANION(dev);
792 	const struct of_device_id *match = NULL;
793 
794 	if (!acpi_of_match_device(adev, dev->driver->of_match_table, &match))
795 		return NULL;
796 
797 	return match->data;
798 }
799 
800 const void *acpi_device_get_match_data(const struct device *dev)
801 {
802 	const struct acpi_device_id *match;
803 
804 	if (!dev->driver->acpi_match_table)
805 		return acpi_of_device_get_match_data(dev);
806 
807 	match = acpi_match_device(dev->driver->acpi_match_table, dev);
808 	if (!match)
809 		return NULL;
810 
811 	return (const void *)match->driver_data;
812 }
813 EXPORT_SYMBOL_GPL(acpi_device_get_match_data);
814 
815 int acpi_match_device_ids(struct acpi_device *device,
816 			  const struct acpi_device_id *ids)
817 {
818 	return __acpi_match_device(device, ids, NULL, NULL, NULL) ? 0 : -ENOENT;
819 }
820 EXPORT_SYMBOL(acpi_match_device_ids);
821 
822 bool acpi_driver_match_device(struct device *dev,
823 			      const struct device_driver *drv)
824 {
825 	if (!drv->acpi_match_table)
826 		return acpi_of_match_device(ACPI_COMPANION(dev),
827 					    drv->of_match_table,
828 					    NULL);
829 
830 	return __acpi_match_device(acpi_companion_match(dev),
831 				   drv->acpi_match_table, drv->of_match_table,
832 				   NULL, NULL);
833 }
834 EXPORT_SYMBOL_GPL(acpi_driver_match_device);
835 
836 /* --------------------------------------------------------------------------
837                               ACPI Driver Management
838    -------------------------------------------------------------------------- */
839 
840 /**
841  * acpi_bus_register_driver - register a driver with the ACPI bus
842  * @driver: driver being registered
843  *
844  * Registers a driver with the ACPI bus.  Searches the namespace for all
845  * devices that match the driver's criteria and binds.  Returns zero for
846  * success or a negative error status for failure.
847  */
848 int acpi_bus_register_driver(struct acpi_driver *driver)
849 {
850 	int ret;
851 
852 	if (acpi_disabled)
853 		return -ENODEV;
854 	driver->drv.name = driver->name;
855 	driver->drv.bus = &acpi_bus_type;
856 	driver->drv.owner = driver->owner;
857 
858 	ret = driver_register(&driver->drv);
859 	return ret;
860 }
861 
862 EXPORT_SYMBOL(acpi_bus_register_driver);
863 
864 /**
865  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
866  * @driver: driver to unregister
867  *
868  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
869  * devices that match the driver's criteria and unbinds.
870  */
871 void acpi_bus_unregister_driver(struct acpi_driver *driver)
872 {
873 	driver_unregister(&driver->drv);
874 }
875 
876 EXPORT_SYMBOL(acpi_bus_unregister_driver);
877 
878 /* --------------------------------------------------------------------------
879                               ACPI Bus operations
880    -------------------------------------------------------------------------- */
881 
882 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
883 {
884 	struct acpi_device *acpi_dev = to_acpi_device(dev);
885 	struct acpi_driver *acpi_drv = to_acpi_driver(drv);
886 
887 	return acpi_dev->flags.match_driver
888 		&& !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
889 }
890 
891 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
892 {
893 	return __acpi_device_uevent_modalias(to_acpi_device(dev), env);
894 }
895 
896 static int acpi_device_probe(struct device *dev)
897 {
898 	struct acpi_device *acpi_dev = to_acpi_device(dev);
899 	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
900 	int ret;
901 
902 	if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
903 		return -EINVAL;
904 
905 	if (!acpi_drv->ops.add)
906 		return -ENOSYS;
907 
908 	ret = acpi_drv->ops.add(acpi_dev);
909 	if (ret)
910 		return ret;
911 
912 	acpi_dev->driver = acpi_drv;
913 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
914 			  "Driver [%s] successfully bound to device [%s]\n",
915 			  acpi_drv->name, acpi_dev->pnp.bus_id));
916 
917 	if (acpi_drv->ops.notify) {
918 		ret = acpi_device_install_notify_handler(acpi_dev);
919 		if (ret) {
920 			if (acpi_drv->ops.remove)
921 				acpi_drv->ops.remove(acpi_dev);
922 
923 			acpi_dev->driver = NULL;
924 			acpi_dev->driver_data = NULL;
925 			return ret;
926 		}
927 	}
928 
929 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
930 			  acpi_drv->name, acpi_dev->pnp.bus_id));
931 	get_device(dev);
932 	return 0;
933 }
934 
935 static int acpi_device_remove(struct device *dev)
936 {
937 	struct acpi_device *acpi_dev = to_acpi_device(dev);
938 	struct acpi_driver *acpi_drv = acpi_dev->driver;
939 
940 	if (acpi_drv) {
941 		if (acpi_drv->ops.notify)
942 			acpi_device_remove_notify_handler(acpi_dev);
943 		if (acpi_drv->ops.remove)
944 			acpi_drv->ops.remove(acpi_dev);
945 	}
946 	acpi_dev->driver = NULL;
947 	acpi_dev->driver_data = NULL;
948 
949 	put_device(dev);
950 	return 0;
951 }
952 
953 struct bus_type acpi_bus_type = {
954 	.name		= "acpi",
955 	.match		= acpi_bus_match,
956 	.probe		= acpi_device_probe,
957 	.remove		= acpi_device_remove,
958 	.uevent		= acpi_device_uevent,
959 };
960 
961 /* --------------------------------------------------------------------------
962                              Initialization/Cleanup
963    -------------------------------------------------------------------------- */
964 
965 static int __init acpi_bus_init_irq(void)
966 {
967 	acpi_status status;
968 	char *message = NULL;
969 
970 
971 	/*
972 	 * Let the system know what interrupt model we are using by
973 	 * evaluating the \_PIC object, if exists.
974 	 */
975 
976 	switch (acpi_irq_model) {
977 	case ACPI_IRQ_MODEL_PIC:
978 		message = "PIC";
979 		break;
980 	case ACPI_IRQ_MODEL_IOAPIC:
981 		message = "IOAPIC";
982 		break;
983 	case ACPI_IRQ_MODEL_IOSAPIC:
984 		message = "IOSAPIC";
985 		break;
986 	case ACPI_IRQ_MODEL_GIC:
987 		message = "GIC";
988 		break;
989 	case ACPI_IRQ_MODEL_PLATFORM:
990 		message = "platform specific model";
991 		break;
992 	default:
993 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
994 		return -ENODEV;
995 	}
996 
997 	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
998 
999 	status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
1000 	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
1001 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
1002 		return -ENODEV;
1003 	}
1004 
1005 	return 0;
1006 }
1007 
1008 /**
1009  * acpi_early_init - Initialize ACPICA and populate the ACPI namespace.
1010  *
1011  * The ACPI tables are accessible after this, but the handling of events has not
1012  * been initialized and the global lock is not available yet, so AML should not
1013  * be executed at this point.
1014  *
1015  * Doing this before switching the EFI runtime services to virtual mode allows
1016  * the EfiBootServices memory to be freed slightly earlier on boot.
1017  */
1018 void __init acpi_early_init(void)
1019 {
1020 	acpi_status status;
1021 
1022 	if (acpi_disabled)
1023 		return;
1024 
1025 	printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
1026 
1027 	/* enable workarounds, unless strict ACPI spec. compliance */
1028 	if (!acpi_strict)
1029 		acpi_gbl_enable_interpreter_slack = TRUE;
1030 
1031 	acpi_permanent_mmap = true;
1032 
1033 #ifdef CONFIG_X86
1034 	/*
1035 	 * If the machine falls into the DMI check table,
1036 	 * DSDT will be copied to memory.
1037 	 * Note that calling dmi_check_system() here on other architectures
1038 	 * would not be OK because only x86 initializes dmi early enough.
1039 	 * Thankfully only x86 systems need such quirks for now.
1040 	 */
1041 	dmi_check_system(dsdt_dmi_table);
1042 #endif
1043 
1044 	status = acpi_reallocate_root_table();
1045 	if (ACPI_FAILURE(status)) {
1046 		printk(KERN_ERR PREFIX
1047 		       "Unable to reallocate ACPI tables\n");
1048 		goto error0;
1049 	}
1050 
1051 	status = acpi_initialize_subsystem();
1052 	if (ACPI_FAILURE(status)) {
1053 		printk(KERN_ERR PREFIX
1054 		       "Unable to initialize the ACPI Interpreter\n");
1055 		goto error0;
1056 	}
1057 
1058 #ifdef CONFIG_X86
1059 	if (!acpi_ioapic) {
1060 		/* compatible (0) means level (3) */
1061 		if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
1062 			acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
1063 			acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
1064 		}
1065 		/* Set PIC-mode SCI trigger type */
1066 		acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
1067 					 (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
1068 	} else {
1069 		/*
1070 		 * now that acpi_gbl_FADT is initialized,
1071 		 * update it with result from INT_SRC_OVR parsing
1072 		 */
1073 		acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
1074 	}
1075 #endif
1076 	return;
1077 
1078  error0:
1079 	disable_acpi();
1080 }
1081 
1082 /**
1083  * acpi_subsystem_init - Finalize the early initialization of ACPI.
1084  *
1085  * Switch over the platform to the ACPI mode (if possible).
1086  *
1087  * Doing this too early is generally unsafe, but at the same time it needs to be
1088  * done before all things that really depend on ACPI.  The right spot appears to
1089  * be before finalizing the EFI initialization.
1090  */
1091 void __init acpi_subsystem_init(void)
1092 {
1093 	acpi_status status;
1094 
1095 	if (acpi_disabled)
1096 		return;
1097 
1098 	status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
1099 	if (ACPI_FAILURE(status)) {
1100 		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
1101 		disable_acpi();
1102 	} else {
1103 		/*
1104 		 * If the system is using ACPI then we can be reasonably
1105 		 * confident that any regulators are managed by the firmware
1106 		 * so tell the regulator core it has everything it needs to
1107 		 * know.
1108 		 */
1109 		regulator_has_full_constraints();
1110 	}
1111 }
1112 
1113 static acpi_status acpi_bus_table_handler(u32 event, void *table, void *context)
1114 {
1115 	acpi_scan_table_handler(event, table, context);
1116 
1117 	return acpi_sysfs_table_handler(event, table, context);
1118 }
1119 
1120 static int __init acpi_bus_init(void)
1121 {
1122 	int result;
1123 	acpi_status status;
1124 
1125 	acpi_os_initialize1();
1126 
1127 	status = acpi_load_tables();
1128 	if (ACPI_FAILURE(status)) {
1129 		printk(KERN_ERR PREFIX
1130 		       "Unable to load the System Description Tables\n");
1131 		goto error1;
1132 	}
1133 
1134 	/*
1135 	 * ACPI 2.0 requires the EC driver to be loaded and work before the EC
1136 	 * device is found in the namespace.
1137 	 *
1138 	 * This is accomplished by looking for the ECDT table and getting the EC
1139 	 * parameters out of that.
1140 	 *
1141 	 * Do that before calling acpi_initialize_objects() which may trigger EC
1142 	 * address space accesses.
1143 	 */
1144 	acpi_ec_ecdt_probe();
1145 
1146 	status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
1147 	if (ACPI_FAILURE(status)) {
1148 		printk(KERN_ERR PREFIX
1149 		       "Unable to start the ACPI Interpreter\n");
1150 		goto error1;
1151 	}
1152 
1153 	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
1154 	if (ACPI_FAILURE(status)) {
1155 		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
1156 		goto error1;
1157 	}
1158 
1159 	/* Set capability bits for _OSC under processor scope */
1160 	acpi_early_processor_osc();
1161 
1162 	/*
1163 	 * _OSC method may exist in module level code,
1164 	 * so it must be run after ACPI_FULL_INITIALIZATION
1165 	 */
1166 	acpi_bus_osc_support();
1167 
1168 	/*
1169 	 * _PDC control method may load dynamic SSDT tables,
1170 	 * and we need to install the table handler before that.
1171 	 */
1172 	status = acpi_install_table_handler(acpi_bus_table_handler, NULL);
1173 
1174 	acpi_sysfs_init();
1175 
1176 	acpi_early_processor_set_pdc();
1177 
1178 	/*
1179 	 * Maybe EC region is required at bus_scan/acpi_get_devices. So it
1180 	 * is necessary to enable it as early as possible.
1181 	 */
1182 	acpi_ec_dsdt_probe();
1183 
1184 	printk(KERN_INFO PREFIX "Interpreter enabled\n");
1185 
1186 	/* Initialize sleep structures */
1187 	acpi_sleep_init();
1188 
1189 	/*
1190 	 * Get the system interrupt model and evaluate \_PIC.
1191 	 */
1192 	result = acpi_bus_init_irq();
1193 	if (result)
1194 		goto error1;
1195 
1196 	/*
1197 	 * Register the for all standard device notifications.
1198 	 */
1199 	status =
1200 	    acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
1201 					&acpi_bus_notify, NULL);
1202 	if (ACPI_FAILURE(status)) {
1203 		printk(KERN_ERR PREFIX
1204 		       "Unable to register for device notifications\n");
1205 		goto error1;
1206 	}
1207 
1208 	/*
1209 	 * Create the top ACPI proc directory
1210 	 */
1211 	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
1212 
1213 	result = bus_register(&acpi_bus_type);
1214 	if (!result)
1215 		return 0;
1216 
1217 	/* Mimic structured exception handling */
1218       error1:
1219 	acpi_terminate();
1220 	return -ENODEV;
1221 }
1222 
1223 struct kobject *acpi_kobj;
1224 EXPORT_SYMBOL_GPL(acpi_kobj);
1225 
1226 static int __init acpi_init(void)
1227 {
1228 	int result;
1229 
1230 	if (acpi_disabled) {
1231 		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
1232 		return -ENODEV;
1233 	}
1234 
1235 	acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
1236 	if (!acpi_kobj) {
1237 		printk(KERN_WARNING "%s: kset create error\n", __func__);
1238 		acpi_kobj = NULL;
1239 	}
1240 
1241 	result = acpi_bus_init();
1242 	if (result) {
1243 		disable_acpi();
1244 		return result;
1245 	}
1246 
1247 	pci_mmcfg_late_init();
1248 	acpi_iort_init();
1249 	acpi_scan_init();
1250 	acpi_ec_init();
1251 	acpi_debugfs_init();
1252 	acpi_sleep_proc_init();
1253 	acpi_wakeup_device_init();
1254 	acpi_debugger_init();
1255 	acpi_setup_sb_notify_handler();
1256 	return 0;
1257 }
1258 
1259 subsys_initcall(acpi_init);
1260