1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: evregion - Operation Region support
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acevents.h"
13#include "acnamesp.h"
14#include "acinterp.h"
15
16#define _COMPONENT ACPI_EVENTS
17ACPI_MODULE_NAME("evregion")
18
19extern u8 acpi_gbl_default_address_spaces[];
20
21/* Local prototypes */
22
23static void
24acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
25 acpi_adr_space_type space_id);
26
27static acpi_status
28acpi_ev_reg_run(acpi_handle obj_handle,
29 u32 level, void *context, void **return_value);
30
31/*******************************************************************************
32 *
33 * FUNCTION: acpi_ev_initialize_op_regions
34 *
35 * PARAMETERS: None
36 *
37 * RETURN: Status
38 *
39 * DESCRIPTION: Execute _REG methods for all Operation Regions that have
40 * an installed default region handler.
41 *
42 ******************************************************************************/
43
44acpi_status acpi_ev_initialize_op_regions(void)
45{
46 acpi_status status;
47 u32 i;
48
49 ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
50
51 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
52 if (ACPI_FAILURE(status)) {
53 return_ACPI_STATUS(status);
54 }
55
56 /* Run the _REG methods for op_regions in each default address space */
57
58 for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
59 /*
60 * Make sure the installed handler is the DEFAULT handler. If not the
61 * default, the _REG methods will have already been run (when the
62 * handler was installed)
63 */
64 if (acpi_ev_has_default_handler(node: acpi_gbl_root_node,
65 space_id: acpi_gbl_default_address_spaces
66 [i])) {
67 acpi_ev_execute_reg_methods(node: acpi_gbl_root_node,
68 space_id: acpi_gbl_default_address_spaces
69 [i], ACPI_REG_CONNECT);
70 }
71 }
72
73 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
74 return_ACPI_STATUS(status);
75}
76
77/*******************************************************************************
78 *
79 * FUNCTION: acpi_ev_address_space_dispatch
80 *
81 * PARAMETERS: region_obj - Internal region object
82 * field_obj - Corresponding field. Can be NULL.
83 * function - Read or Write operation
84 * region_offset - Where in the region to read or write
85 * bit_width - Field width in bits (8, 16, 32, or 64)
86 * value - Pointer to in or out value, must be
87 * a full 64-bit integer
88 *
89 * RETURN: Status
90 *
91 * DESCRIPTION: Dispatch an address space or operation region access to
92 * a previously installed handler.
93 *
94 * NOTE: During early initialization, we always install the default region
95 * handlers for Memory, I/O and PCI_Config. This ensures that these operation
96 * region address spaces are always available as per the ACPI specification.
97 * This is especially needed in order to support the execution of
98 * module-level AML code during loading of the ACPI tables.
99 *
100 ******************************************************************************/
101
102acpi_status
103acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
104 union acpi_operand_object *field_obj,
105 u32 function,
106 u32 region_offset, u32 bit_width, u64 *value)
107{
108 acpi_status status;
109 acpi_adr_space_handler handler;
110 acpi_adr_space_setup region_setup;
111 union acpi_operand_object *handler_desc;
112 union acpi_operand_object *region_obj2;
113 void *region_context = NULL;
114 struct acpi_connection_info *context;
115 acpi_mutex context_mutex;
116 u8 context_locked;
117 acpi_physical_address address;
118
119 ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
120
121 region_obj2 = acpi_ns_get_secondary_object(obj_desc: region_obj);
122 if (!region_obj2) {
123 return_ACPI_STATUS(AE_NOT_EXIST);
124 }
125
126 /* Ensure that there is a handler associated with this region */
127
128 handler_desc = region_obj->region.handler;
129 if (!handler_desc) {
130 ACPI_ERROR((AE_INFO,
131 "No handler for Region [%4.4s] (%p) [%s]",
132 acpi_ut_get_node_name(region_obj->region.node),
133 region_obj,
134 acpi_ut_get_region_name(region_obj->region.
135 space_id)));
136
137 return_ACPI_STATUS(AE_NOT_EXIST);
138 }
139
140 context = handler_desc->address_space.context;
141 context_mutex = handler_desc->address_space.context_mutex;
142 context_locked = FALSE;
143
144 /*
145 * It may be the case that the region has never been initialized.
146 * Some types of regions require special init code
147 */
148 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
149
150 /* This region has not been initialized yet, do it */
151
152 region_setup = handler_desc->address_space.setup;
153 if (!region_setup) {
154
155 /* No initialization routine, exit with error */
156
157 ACPI_ERROR((AE_INFO,
158 "No init routine for region(%p) [%s]",
159 region_obj,
160 acpi_ut_get_region_name(region_obj->region.
161 space_id)));
162 return_ACPI_STATUS(AE_NOT_EXIST);
163 }
164
165 if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
166 struct acpi_pcc_info *ctx =
167 handler_desc->address_space.context;
168
169 ctx->internal_buffer =
170 field_obj->field.internal_pcc_buffer;
171 ctx->length = (u16)region_obj->region.length;
172 ctx->subspace_id = (u8)region_obj->region.address;
173 }
174
175 if (region_obj->region.space_id ==
176 ACPI_ADR_SPACE_FIXED_HARDWARE) {
177 struct acpi_ffh_info *ctx =
178 handler_desc->address_space.context;
179
180 ctx->length = region_obj->region.length;
181 ctx->offset = region_obj->region.address;
182 }
183
184 /*
185 * We must exit the interpreter because the region setup will
186 * potentially execute control methods (for example, the _REG method
187 * for this region)
188 */
189 acpi_ex_exit_interpreter();
190
191 status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
192 context, &region_context);
193
194 /* Re-enter the interpreter */
195
196 acpi_ex_enter_interpreter();
197
198 /* Check for failure of the Region Setup */
199
200 if (ACPI_FAILURE(status)) {
201 ACPI_EXCEPTION((AE_INFO, status,
202 "During region initialization: [%s]",
203 acpi_ut_get_region_name(region_obj->
204 region.
205 space_id)));
206 return_ACPI_STATUS(status);
207 }
208
209 /* Region initialization may have been completed by region_setup */
210
211 if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
212 region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
213
214 /*
215 * Save the returned context for use in all accesses to
216 * the handler for this particular region
217 */
218 if (!(region_obj2->extra.region_context)) {
219 region_obj2->extra.region_context =
220 region_context;
221 }
222 }
223 }
224
225 /* We have everything we need, we can invoke the address space handler */
226
227 handler = handler_desc->address_space.handler;
228 address = (region_obj->region.address + region_offset);
229
230 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
231 "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
232 &region_obj->region.handler->address_space, handler,
233 ACPI_FORMAT_UINT64(address),
234 acpi_ut_get_region_name(region_obj->region.
235 space_id)));
236
237 if (!(handler_desc->address_space.handler_flags &
238 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
239 /*
240 * For handlers other than the default (supplied) handlers, we must
241 * exit the interpreter because the handler *might* block -- we don't
242 * know what it will do, so we can't hold the lock on the interpreter.
243 */
244 acpi_ex_exit_interpreter();
245 }
246
247 /*
248 * Special handling for generic_serial_bus and general_purpose_io:
249 * There are three extra parameters that must be passed to the
250 * handler via the context:
251 * 1) Connection buffer, a resource template from Connection() op
252 * 2) Length of the above buffer
253 * 3) Actual access length from the access_as() op
254 *
255 * Since we pass these extra parameters via the context, which is
256 * shared between threads, we must lock the context to avoid these
257 * parameters being changed from another thread before the handler
258 * has completed running.
259 *
260 * In addition, for general_purpose_io, the Address and bit_width fields
261 * are defined as follows:
262 * 1) Address is the pin number index of the field (bit offset from
263 * the previous Connection)
264 * 2) bit_width is the actual bit length of the field (number of pins)
265 */
266 if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS ||
267 region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
268 context && field_obj) {
269
270 status =
271 acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
272 if (ACPI_FAILURE(status)) {
273 goto re_enter_interpreter;
274 }
275
276 context_locked = TRUE;
277
278 /* Get the Connection (resource_template) buffer */
279
280 context->connection = field_obj->field.resource_buffer;
281 context->length = field_obj->field.resource_length;
282 context->access_length = field_obj->field.access_length;
283
284 if (region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) {
285 address = field_obj->field.pin_number_index;
286 bit_width = field_obj->field.bit_length;
287 }
288 }
289
290 /* Call the handler */
291
292 status = handler(function, address, bit_width, value, context,
293 region_obj2->extra.region_context);
294
295 if (context_locked) {
296 acpi_os_release_mutex(context_mutex);
297 }
298
299 if (ACPI_FAILURE(status)) {
300 ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
301 acpi_ut_get_region_name(region_obj->region.
302 space_id)));
303
304 /*
305 * Special case for an EC timeout. These are seen so frequently
306 * that an additional error message is helpful
307 */
308 if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
309 (status == AE_TIME)) {
310 ACPI_ERROR((AE_INFO,
311 "Timeout from EC hardware or EC device driver"));
312 }
313 }
314
315re_enter_interpreter:
316 if (!(handler_desc->address_space.handler_flags &
317 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
318 /*
319 * We just returned from a non-default handler, we must re-enter the
320 * interpreter
321 */
322 acpi_ex_enter_interpreter();
323 }
324
325 return_ACPI_STATUS(status);
326}
327
328/*******************************************************************************
329 *
330 * FUNCTION: acpi_ev_detach_region
331 *
332 * PARAMETERS: region_obj - Region Object
333 * acpi_ns_is_locked - Namespace Region Already Locked?
334 *
335 * RETURN: None
336 *
337 * DESCRIPTION: Break the association between the handler and the region
338 * this is a two way association.
339 *
340 ******************************************************************************/
341
342void
343acpi_ev_detach_region(union acpi_operand_object *region_obj,
344 u8 acpi_ns_is_locked)
345{
346 union acpi_operand_object *handler_obj;
347 union acpi_operand_object *obj_desc;
348 union acpi_operand_object *start_desc;
349 union acpi_operand_object **last_obj_ptr;
350 acpi_adr_space_setup region_setup;
351 void **region_context;
352 union acpi_operand_object *region_obj2;
353 acpi_status status;
354
355 ACPI_FUNCTION_TRACE(ev_detach_region);
356
357 region_obj2 = acpi_ns_get_secondary_object(obj_desc: region_obj);
358 if (!region_obj2) {
359 return_VOID;
360 }
361 region_context = &region_obj2->extra.region_context;
362
363 /* Get the address handler from the region object */
364
365 handler_obj = region_obj->region.handler;
366 if (!handler_obj) {
367
368 /* This region has no handler, all done */
369
370 return_VOID;
371 }
372
373 /* Find this region in the handler's list */
374
375 obj_desc = handler_obj->address_space.region_list;
376 start_desc = obj_desc;
377 last_obj_ptr = &handler_obj->address_space.region_list;
378
379 while (obj_desc) {
380
381 /* Is this the correct Region? */
382
383 if (obj_desc == region_obj) {
384 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
385 "Removing Region %p from address handler %p\n",
386 region_obj, handler_obj));
387
388 /* This is it, remove it from the handler's list */
389
390 *last_obj_ptr = obj_desc->region.next;
391 obj_desc->region.next = NULL; /* Must clear field */
392
393 if (acpi_ns_is_locked) {
394 status =
395 acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
396 if (ACPI_FAILURE(status)) {
397 return_VOID;
398 }
399 }
400
401 /* Now stop region accesses by executing the _REG method */
402
403 status =
404 acpi_ev_execute_reg_method(region_obj,
405 ACPI_REG_DISCONNECT);
406 if (ACPI_FAILURE(status)) {
407 ACPI_EXCEPTION((AE_INFO, status,
408 "from region _REG, [%s]",
409 acpi_ut_get_region_name
410 (region_obj->region.space_id)));
411 }
412
413 if (acpi_ns_is_locked) {
414 status =
415 acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
416 if (ACPI_FAILURE(status)) {
417 return_VOID;
418 }
419 }
420
421 /*
422 * If the region has been activated, call the setup handler with
423 * the deactivate notification
424 */
425 if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
426 region_setup = handler_obj->address_space.setup;
427 status =
428 region_setup(region_obj,
429 ACPI_REGION_DEACTIVATE,
430 handler_obj->address_space.
431 context, region_context);
432
433 /*
434 * region_context should have been released by the deactivate
435 * operation. We don't need access to it anymore here.
436 */
437 if (region_context) {
438 *region_context = NULL;
439 }
440
441 /* Init routine may fail, Just ignore errors */
442
443 if (ACPI_FAILURE(status)) {
444 ACPI_EXCEPTION((AE_INFO, status,
445 "from region handler - deactivate, [%s]",
446 acpi_ut_get_region_name
447 (region_obj->region.
448 space_id)));
449 }
450
451 region_obj->region.flags &=
452 ~(AOPOBJ_SETUP_COMPLETE);
453 }
454
455 /*
456 * Remove handler reference in the region
457 *
458 * NOTE: this doesn't mean that the region goes away, the region
459 * is just inaccessible as indicated to the _REG method
460 *
461 * If the region is on the handler's list, this must be the
462 * region's handler
463 */
464 region_obj->region.handler = NULL;
465 acpi_ut_remove_reference(object: handler_obj);
466
467 return_VOID;
468 }
469
470 /* Walk the linked list of handlers */
471
472 last_obj_ptr = &obj_desc->region.next;
473 obj_desc = obj_desc->region.next;
474
475 /* Prevent infinite loop if list is corrupted */
476
477 if (obj_desc == start_desc) {
478 ACPI_ERROR((AE_INFO,
479 "Circular handler list in region object %p",
480 region_obj));
481 return_VOID;
482 }
483 }
484
485 /* If we get here, the region was not in the handler's region list */
486
487 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
488 "Cannot remove region %p from address handler %p\n",
489 region_obj, handler_obj));
490
491 return_VOID;
492}
493
494/*******************************************************************************
495 *
496 * FUNCTION: acpi_ev_attach_region
497 *
498 * PARAMETERS: handler_obj - Handler Object
499 * region_obj - Region Object
500 * acpi_ns_is_locked - Namespace Region Already Locked?
501 *
502 * RETURN: None
503 *
504 * DESCRIPTION: Create the association between the handler and the region
505 * this is a two way association.
506 *
507 ******************************************************************************/
508
509acpi_status
510acpi_ev_attach_region(union acpi_operand_object *handler_obj,
511 union acpi_operand_object *region_obj,
512 u8 acpi_ns_is_locked)
513{
514
515 ACPI_FUNCTION_TRACE(ev_attach_region);
516
517 /* Install the region's handler */
518
519 if (region_obj->region.handler) {
520 return_ACPI_STATUS(AE_ALREADY_EXISTS);
521 }
522
523 ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
524 "Adding Region [%4.4s] %p to address handler %p [%s]\n",
525 acpi_ut_get_node_name(region_obj->region.node),
526 region_obj, handler_obj,
527 acpi_ut_get_region_name(region_obj->region.
528 space_id)));
529
530 /* Link this region to the front of the handler's list */
531
532 region_obj->region.next = handler_obj->address_space.region_list;
533 handler_obj->address_space.region_list = region_obj;
534 region_obj->region.handler = handler_obj;
535 acpi_ut_add_reference(object: handler_obj);
536
537 return_ACPI_STATUS(AE_OK);
538}
539
540/*******************************************************************************
541 *
542 * FUNCTION: acpi_ev_execute_reg_method
543 *
544 * PARAMETERS: region_obj - Region object
545 * function - Passed to _REG: On (1) or Off (0)
546 *
547 * RETURN: Status
548 *
549 * DESCRIPTION: Execute _REG method for a region
550 *
551 ******************************************************************************/
552
553acpi_status
554acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
555{
556 struct acpi_evaluate_info *info;
557 union acpi_operand_object *args[3];
558 union acpi_operand_object *region_obj2;
559 const acpi_name *reg_name_ptr =
560 ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
561 struct acpi_namespace_node *method_node;
562 struct acpi_namespace_node *node;
563 acpi_status status;
564
565 ACPI_FUNCTION_TRACE(ev_execute_reg_method);
566
567 if (!acpi_gbl_namespace_initialized ||
568 region_obj->region.handler == NULL) {
569 return_ACPI_STATUS(AE_OK);
570 }
571
572 region_obj2 = acpi_ns_get_secondary_object(obj_desc: region_obj);
573 if (!region_obj2) {
574 return_ACPI_STATUS(AE_NOT_EXIST);
575 }
576
577 /*
578 * Find any "_REG" method associated with this region definition.
579 * The method should always be updated as this function may be
580 * invoked after a namespace change.
581 */
582 node = region_obj->region.node->parent;
583 status =
584 acpi_ns_search_one_scope(entry_name: *reg_name_ptr, node, ACPI_TYPE_METHOD,
585 ret_node: &method_node);
586 if (ACPI_SUCCESS(status)) {
587 /*
588 * The _REG method is optional and there can be only one per
589 * region definition. This will be executed when the handler is
590 * attached or removed.
591 */
592 region_obj2->extra.method_REG = method_node;
593 }
594 if (region_obj2->extra.method_REG == NULL) {
595 return_ACPI_STATUS(AE_OK);
596 }
597
598 /* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
599
600 if ((function == ACPI_REG_CONNECT &&
601 region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
602 (function == ACPI_REG_DISCONNECT &&
603 !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
604 return_ACPI_STATUS(AE_OK);
605 }
606
607 /* Allocate and initialize the evaluation information block */
608
609 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
610 if (!info) {
611 return_ACPI_STATUS(AE_NO_MEMORY);
612 }
613
614 info->prefix_node = region_obj2->extra.method_REG;
615 info->relative_pathname = NULL;
616 info->parameters = args;
617 info->flags = ACPI_IGNORE_RETURN_VALUE;
618
619 /*
620 * The _REG method has two arguments:
621 *
622 * arg0 - Integer:
623 * Operation region space ID Same value as region_obj->Region.space_id
624 *
625 * arg1 - Integer:
626 * connection status 1 for connecting the handler, 0 for disconnecting
627 * the handler (Passed as a parameter)
628 */
629 args[0] =
630 acpi_ut_create_integer_object(value: (u64)region_obj->region.space_id);
631 if (!args[0]) {
632 status = AE_NO_MEMORY;
633 goto cleanup1;
634 }
635
636 args[1] = acpi_ut_create_integer_object(value: (u64)function);
637 if (!args[1]) {
638 status = AE_NO_MEMORY;
639 goto cleanup2;
640 }
641
642 args[2] = NULL; /* Terminate list */
643
644 /* Execute the method, no return value */
645
646 ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
647 (ACPI_TYPE_METHOD, info->prefix_node, NULL));
648
649 status = acpi_ns_evaluate(info);
650 acpi_ut_remove_reference(object: args[1]);
651
652 if (ACPI_FAILURE(status)) {
653 goto cleanup2;
654 }
655
656 if (function == ACPI_REG_CONNECT) {
657 region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
658 } else {
659 region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
660 }
661
662cleanup2:
663 acpi_ut_remove_reference(object: args[0]);
664
665cleanup1:
666 ACPI_FREE(info);
667 return_ACPI_STATUS(status);
668}
669
670/*******************************************************************************
671 *
672 * FUNCTION: acpi_ev_execute_reg_methods
673 *
674 * PARAMETERS: node - Namespace node for the device
675 * space_id - The address space ID
676 * function - Passed to _REG: On (1) or Off (0)
677 *
678 * RETURN: None
679 *
680 * DESCRIPTION: Run all _REG methods for the input Space ID;
681 * Note: assumes namespace is locked, or system init time.
682 *
683 ******************************************************************************/
684
685void
686acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
687 acpi_adr_space_type space_id, u32 function)
688{
689 struct acpi_reg_walk_info info;
690
691 ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
692
693 /*
694 * These address spaces do not need a call to _REG, since the ACPI
695 * specification defines them as: "must always be accessible". Since
696 * they never change state (never become unavailable), no need to ever
697 * call _REG on them. Also, a data_table is not a "real" address space,
698 * so do not call _REG. September 2018.
699 */
700 if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
701 (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
702 (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
703 return_VOID;
704 }
705
706 info.space_id = space_id;
707 info.function = function;
708 info.reg_run_count = 0;
709
710 ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
711 " Running _REG methods for SpaceId %s\n",
712 acpi_ut_get_region_name(info.space_id)));
713
714 /*
715 * Run all _REG methods for all Operation Regions for this space ID. This
716 * is a separate walk in order to handle any interdependencies between
717 * regions and _REG methods. (i.e. handlers must be installed for all
718 * regions of this Space ID before we can run any _REG methods)
719 */
720 (void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, start_object: node, ACPI_UINT32_MAX,
721 ACPI_NS_WALK_UNLOCK, descending_callback: acpi_ev_reg_run, NULL,
722 context: &info, NULL);
723
724 /*
725 * Special case for EC and GPIO: handle "orphan" _REG methods with
726 * no region.
727 */
728 if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
729 acpi_ev_execute_orphan_reg_method(device_node: node, space_id);
730 }
731
732 ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
733 " Executed %u _REG methods for SpaceId %s\n",
734 info.reg_run_count,
735 acpi_ut_get_region_name(info.space_id)));
736
737 return_VOID;
738}
739
740/*******************************************************************************
741 *
742 * FUNCTION: acpi_ev_reg_run
743 *
744 * PARAMETERS: walk_namespace callback
745 *
746 * DESCRIPTION: Run _REG method for region objects of the requested spaceID
747 *
748 ******************************************************************************/
749
750static acpi_status
751acpi_ev_reg_run(acpi_handle obj_handle,
752 u32 level, void *context, void **return_value)
753{
754 union acpi_operand_object *obj_desc;
755 struct acpi_namespace_node *node;
756 acpi_status status;
757 struct acpi_reg_walk_info *info;
758
759 info = ACPI_CAST_PTR(struct acpi_reg_walk_info, context);
760
761 /* Convert and validate the device handle */
762
763 node = acpi_ns_validate_handle(handle: obj_handle);
764 if (!node) {
765 return (AE_BAD_PARAMETER);
766 }
767
768 /*
769 * We only care about regions and objects that are allowed to have
770 * address space handlers
771 */
772 if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
773 return (AE_OK);
774 }
775
776 /* Check for an existing internal object */
777
778 obj_desc = acpi_ns_get_attached_object(node);
779 if (!obj_desc) {
780
781 /* No object, just exit */
782
783 return (AE_OK);
784 }
785
786 /* Object is a Region */
787
788 if (obj_desc->region.space_id != info->space_id) {
789
790 /* This region is for a different address space, just ignore it */
791
792 return (AE_OK);
793 }
794
795 info->reg_run_count++;
796 status = acpi_ev_execute_reg_method(region_obj: obj_desc, function: info->function);
797 return (status);
798}
799
800/*******************************************************************************
801 *
802 * FUNCTION: acpi_ev_execute_orphan_reg_method
803 *
804 * PARAMETERS: device_node - Namespace node for an ACPI device
805 * space_id - The address space ID
806 *
807 * RETURN: None
808 *
809 * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
810 * device. This is a _REG method that has no corresponding region
811 * within the device's scope. ACPI tables depending on these
812 * "orphan" _REG methods have been seen for both EC and GPIO
813 * Operation Regions. Presumably the Windows ACPI implementation
814 * always calls the _REG method independent of the presence of
815 * an actual Operation Region with the correct address space ID.
816 *
817 * MUTEX: Assumes the namespace is locked
818 *
819 ******************************************************************************/
820
821static void
822acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
823 acpi_adr_space_type space_id)
824{
825 acpi_handle reg_method;
826 struct acpi_namespace_node *next_node;
827 acpi_status status;
828 struct acpi_object_list args;
829 union acpi_object objects[2];
830
831 ACPI_FUNCTION_TRACE(ev_execute_orphan_reg_method);
832
833 if (!device_node) {
834 return_VOID;
835 }
836
837 /* Namespace is currently locked, must release */
838
839 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
840
841 /* Get a handle to a _REG method immediately under the EC device */
842
843 status = acpi_get_handle(parent: device_node, METHOD_NAME__REG, ret_handle: &reg_method);
844 if (ACPI_FAILURE(status)) {
845 goto exit; /* There is no _REG method present */
846 }
847
848 /*
849 * Execute the _REG method only if there is no Operation Region in
850 * this scope with the Embedded Controller space ID. Otherwise, it
851 * will already have been executed. Note, this allows for Regions
852 * with other space IDs to be present; but the code below will then
853 * execute the _REG method with the embedded_control space_ID argument.
854 */
855 next_node = acpi_ns_get_next_node(parent: device_node, NULL);
856 while (next_node) {
857 if ((next_node->type == ACPI_TYPE_REGION) &&
858 (next_node->object) &&
859 (next_node->object->region.space_id == space_id)) {
860 goto exit; /* Do not execute the _REG */
861 }
862
863 next_node = acpi_ns_get_next_node(parent: device_node, child: next_node);
864 }
865
866 /* Evaluate the _REG(space_id,Connect) method */
867
868 args.count = 2;
869 args.pointer = objects;
870 objects[0].type = ACPI_TYPE_INTEGER;
871 objects[0].integer.value = space_id;
872 objects[1].type = ACPI_TYPE_INTEGER;
873 objects[1].integer.value = ACPI_REG_CONNECT;
874
875 (void)acpi_evaluate_object(object: reg_method, NULL, parameter_objects: &args, NULL);
876
877exit:
878 /* We ignore all errors from above, don't care */
879
880 (void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
881 return_VOID;
882}
883

source code of linux/drivers/acpi/acpica/evregion.c