1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: evxfregn - External Interfaces, ACPI Operation Regions and
5 *                         Address Spaces.
6 *
7 * Copyright (C) 2000 - 2020, Intel Corp.
8 *
9 *****************************************************************************/
10
11#define EXPORT_ACPI_INTERFACES
12
13#include <acpi/acpi.h>
14#include "accommon.h"
15#include "acnamesp.h"
16#include "acevents.h"
17
18#define _COMPONENT          ACPI_EVENTS
19ACPI_MODULE_NAME("evxfregn")
20
21/*******************************************************************************
22 *
23 * FUNCTION:    acpi_install_address_space_handler
24 *
25 * PARAMETERS:  device          - Handle for the device
26 *              space_id        - The address space ID
27 *              handler         - Address of the handler
28 *              setup           - Address of the setup function
29 *              context         - Value passed to the handler on each access
30 *
31 * RETURN:      Status
32 *
33 * DESCRIPTION: Install a handler for all op_regions of a given space_id.
34 *
35 * NOTE: This function should only be called after acpi_enable_subsystem has
36 * been called. This is because any _REG methods associated with the Space ID
37 * are executed here, and these methods can only be safely executed after
38 * the default handlers have been installed and the hardware has been
39 * initialized (via acpi_enable_subsystem.)
40 *
41 ******************************************************************************/
42acpi_status
43acpi_install_address_space_handler(acpi_handle device,
44				   acpi_adr_space_type space_id,
45				   acpi_adr_space_handler handler,
46				   acpi_adr_space_setup setup, void *context)
47{
48	struct acpi_namespace_node *node;
49	acpi_status status;
50
51	ACPI_FUNCTION_TRACE(acpi_install_address_space_handler);
52
53	/* Parameter validation */
54
55	if (!device) {
56		return_ACPI_STATUS(AE_BAD_PARAMETER);
57	}
58
59	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
60	if (ACPI_FAILURE(status)) {
61		return_ACPI_STATUS(status);
62	}
63
64	/* Convert and validate the device handle */
65
66	node = acpi_ns_validate_handle(device);
67	if (!node) {
68		status = AE_BAD_PARAMETER;
69		goto unlock_and_exit;
70	}
71
72	/* Install the handler for all Regions for this Space ID */
73
74	status =
75	    acpi_ev_install_space_handler(node, space_id, handler, setup,
76					  context);
77	if (ACPI_FAILURE(status)) {
78		goto unlock_and_exit;
79	}
80
81	/* Run all _REG methods for this address space */
82
83	acpi_ev_execute_reg_methods(node, space_id, ACPI_REG_CONNECT);
84
85unlock_and_exit:
86	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
87	return_ACPI_STATUS(status);
88}
89
90ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler)
91
92/*******************************************************************************
93 *
94 * FUNCTION:    acpi_remove_address_space_handler
95 *
96 * PARAMETERS:  device          - Handle for the device
97 *              space_id        - The address space ID
98 *              handler         - Address of the handler
99 *
100 * RETURN:      Status
101 *
102 * DESCRIPTION: Remove a previously installed handler.
103 *
104 ******************************************************************************/
105acpi_status
106acpi_remove_address_space_handler(acpi_handle device,
107				  acpi_adr_space_type space_id,
108				  acpi_adr_space_handler handler)
109{
110	union acpi_operand_object *obj_desc;
111	union acpi_operand_object *handler_obj;
112	union acpi_operand_object *region_obj;
113	union acpi_operand_object **last_obj_ptr;
114	struct acpi_namespace_node *node;
115	acpi_status status;
116
117	ACPI_FUNCTION_TRACE(acpi_remove_address_space_handler);
118
119	/* Parameter validation */
120
121	if (!device) {
122		return_ACPI_STATUS(AE_BAD_PARAMETER);
123	}
124
125	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
126	if (ACPI_FAILURE(status)) {
127		return_ACPI_STATUS(status);
128	}
129
130	/* Convert and validate the device handle */
131
132	node = acpi_ns_validate_handle(device);
133	if (!node ||
134	    ((node->type != ACPI_TYPE_DEVICE) &&
135	     (node->type != ACPI_TYPE_PROCESSOR) &&
136	     (node->type != ACPI_TYPE_THERMAL) &&
137	     (node != acpi_gbl_root_node))) {
138		status = AE_BAD_PARAMETER;
139		goto unlock_and_exit;
140	}
141
142	/* Make sure the internal object exists */
143
144	obj_desc = acpi_ns_get_attached_object(node);
145	if (!obj_desc) {
146		status = AE_NOT_EXIST;
147		goto unlock_and_exit;
148	}
149
150	/* Find the address handler the user requested */
151
152	handler_obj = obj_desc->common_notify.handler;
153	last_obj_ptr = &obj_desc->common_notify.handler;
154	while (handler_obj) {
155
156		/* We have a handler, see if user requested this one */
157
158		if (handler_obj->address_space.space_id == space_id) {
159
160			/* Handler must be the same as the installed handler */
161
162			if (handler_obj->address_space.handler != handler) {
163				status = AE_BAD_PARAMETER;
164				goto unlock_and_exit;
165			}
166
167			/* Matched space_id, first dereference this in the Regions */
168
169			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
170					  "Removing address handler %p(%p) for region %s "
171					  "on Device %p(%p)\n",
172					  handler_obj, handler,
173					  acpi_ut_get_region_name(space_id),
174					  node, obj_desc));
175
176			region_obj = handler_obj->address_space.region_list;
177
178			/* Walk the handler's region list */
179
180			while (region_obj) {
181				/*
182				 * First disassociate the handler from the region.
183				 *
184				 * NOTE: this doesn't mean that the region goes away
185				 * The region is just inaccessible as indicated to
186				 * the _REG method
187				 */
188				acpi_ev_detach_region(region_obj, TRUE);
189
190				/*
191				 * Walk the list: Just grab the head because the
192				 * detach_region removed the previous head.
193				 */
194				region_obj =
195				    handler_obj->address_space.region_list;
196			}
197
198			/* Remove this Handler object from the list */
199
200			*last_obj_ptr = handler_obj->address_space.next;
201
202			/* Now we can delete the handler object */
203
204			acpi_os_release_mutex(handler_obj->address_space.
205					      context_mutex);
206			acpi_ut_remove_reference(handler_obj);
207			goto unlock_and_exit;
208		}
209
210		/* Walk the linked list of handlers */
211
212		last_obj_ptr = &handler_obj->address_space.next;
213		handler_obj = handler_obj->address_space.next;
214	}
215
216	/* The handler does not exist */
217
218	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
219			  "Unable to remove address handler %p for %s(%X), DevNode %p, obj %p\n",
220			  handler, acpi_ut_get_region_name(space_id), space_id,
221			  node, obj_desc));
222
223	status = AE_NOT_EXIST;
224
225unlock_and_exit:
226	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
227	return_ACPI_STATUS(status);
228}
229
230ACPI_EXPORT_SYMBOL(acpi_remove_address_space_handler)
231