aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpica/nseval.c
blob: a8d7764c73b740a6aa7229ac90ea978e4e1034fb (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
/*******************************************************************************
 *
 * Module Name: nseval - Object evaluation, includes control method execution
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2008, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include <acpi/accommon.h>
#include <acpi/acparser.h>
#include <acpi/acinterp.h>
#include <acpi/acnamesp.h>

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nseval")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_evaluate
 *
 * PARAMETERS:  Info            - Evaluation info block, contains:
 *                  prefix_node     - Prefix or Method/Object Node to execute
 *                  Pathname        - Name of method to execute, If NULL, the
 *                                    Node is the object to execute
 *                  Parameters      - List of parameters to pass to the method,
 *                                    terminated by NULL. Params itself may be
 *                                    NULL if no parameters are being passed.
 *                  return_object   - Where to put method's return value (if
 *                                    any). If NULL, no value is returned.
 *                  parameter_type  - Type of Parameter list
 *                  return_object   - Where to put method's return value (if
 *                                    any). If NULL, no value is returned.
 *                  Flags           - ACPI_IGNORE_RETURN_VALUE to delete return
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute a control method or return the current value of an
 *              ACPI namespace object.
 *
 * MUTEX:       Locks interpreter
 *
 ******************************************************************************/
acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
{
	acpi_status status;
	struct acpi_namespace_node *node;

	ACPI_FUNCTION_TRACE(ns_evaluate);

	if (!info) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* Initialize the return value to an invalid object */

	info->return_object = NULL;
	info->param_count = 0;

	/*
	 * Get the actual namespace node for the target object. Handles these cases:
	 *
	 * 1) Null node, Pathname (absolute path)
	 * 2) Node, Pathname (path relative to Node)
	 * 3) Node, Null Pathname
	 */
	status = acpi_ns_get_node(info->prefix_node, info->pathname,
				  ACPI_NS_NO_UPSEARCH, &info->resolved_node);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * For a method alias, we must grab the actual method node so that proper
	 * scoping context will be established before execution.
	 */
	if (acpi_ns_get_type(info->resolved_node) ==
	    ACPI_TYPE_LOCAL_METHOD_ALIAS) {
		info->resolved_node =
		    ACPI_CAST_PTR(struct acpi_namespace_node,
				  info->resolved_node->object);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
			  info->resolved_node,
			  acpi_ns_get_attached_object(info->resolved_node)));

	node = info->resolved_node;

	/*
	 * Two major cases here:
	 *
	 * 1) The object is a control method -- execute it
	 * 2) The object is not a method -- just return it's current value
	 */
	if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
		/*
		 * 1) Object is a control method - execute it
		 */

		/* Verify that there is a method object associated with this node */

		info->obj_desc =
		    acpi_ns_get_attached_object(info->resolved_node);
		if (!info->obj_desc) {
			ACPI_ERROR((AE_INFO,
				    "Control method has no attached sub-object"));
			return_ACPI_STATUS(AE_NULL_OBJECT);
		}

		/* Count the number of arguments being passed to the method */

		if (info->parameters) {
			while (info->parameters[info->param_count]) {
				if (info->param_count > ACPI_METHOD_MAX_ARG) {
					return_ACPI_STATUS(AE_LIMIT);
				}
				info->param_count++;
			}
		}


		ACPI_DUMP_PATHNAME(info->resolved_node, "Execute Method:",
				   ACPI_LV_INFO, _COMPONENT);

		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
				  "Method at AML address %p Length %X\n",
				  info->obj_desc->method.aml_start + 1,
				  info->obj_desc->method.aml_length - 1));

		/*
		 * Any namespace deletion must acquire both the namespace and
		 * interpreter locks to ensure that no thread is using the portion of
		 * the namespace that is being deleted.
		 *
		 * Execute the method via the interpreter. The interpreter is locked
		 * here before calling into the AML parser
		 */
		acpi_ex_enter_interpreter();
		status = acpi_ps_execute_method(info);
		acpi_ex_exit_interpreter();
	} else {
		/*
		 * 2) Object is not a method, return its current value
		 *
		 * Disallow certain object types. For these, "evaluation" is undefined.
		 */
		switch (info->resolved_node->type) {
		case ACPI_TYPE_DEVICE:
		case ACPI_TYPE_EVENT:
		case ACPI_TYPE_MUTEX:
		case ACPI_TYPE_REGION:
		case ACPI_TYPE_THERMAL:
		case ACPI_TYPE_LOCAL_SCOPE:

			ACPI_ERROR((AE_INFO,
				    "[%4.4s] Evaluation of object type [%s] is not supported",
				    info->resolved_node->name.ascii,
				    acpi_ut_get_type_name(info->resolved_node->
							  type)));

			return_ACPI_STATUS(AE_TYPE);

		default:
			break;
		}

		/*
		 * Objects require additional resolution steps (e.g., the Node may be
		 * a field that must be read, etc.) -- we can't just grab the object
		 * out of the node.
		 *
		 * Use resolve_node_to_value() to get the associated value.
		 *
		 * NOTE: we can get away with passing in NULL for a walk state because
		 * resolved_node is guaranteed to not be a reference to either a method
		 * local or a method argument (because this interface is never called
		 * from a running method.)
		 *
		 * Even though we do not directly invoke the interpreter for object
		 * resolution, we must lock it because we could access an opregion.
		 * The opregion access code assumes that the interpreter is locked.
		 */
		acpi_ex_enter_interpreter();

		/* Function has a strange interface */

		status =
		    acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
		acpi_ex_exit_interpreter();

		/*
		 * If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
		 * in resolved_node.
		 */
		if (ACPI_SUCCESS(status)) {
			status = AE_CTRL_RETURN_VALUE;
			info->return_object =
			    ACPI_CAST_PTR(union acpi_operand_object,
					  info->resolved_node);

			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
					  "Returning object %p [%s]\n",
					  info->return_object,
					  acpi_ut_get_object_type_name(info->
								       return_object)));
		}
	}

	/*
	 * Check input argument count against the ASL-defined count for a method.
	 * Also check predefined names: argument count and return value against
	 * the ACPI specification. Some incorrect return value types are repaired.
	 */
	(void)acpi_ns_check_predefined_names(node, info->param_count,
		status, &info->return_object);

	/* Check if there is a return value that must be dealt with */

	if (status == AE_CTRL_RETURN_VALUE) {

		/* If caller does not want the return value, delete it */

		if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
			acpi_ut_remove_reference(info->return_object);
			info->return_object = NULL;
		}

		/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */

		status = AE_OK;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
			  "*** Completed evaluation of object %s ***\n",
			  info->pathname));

	/*
	 * Namespace was unlocked by the handling acpi_ns* function, so we
	 * just return
	 */
	return_ACPI_STATUS(status);
}