xref: /linux/drivers/acpi/acpica/uteval.c (revision b14132797d8041a42e03f4ffa1e722da1425adfb)
1 /******************************************************************************
2  *
3  * Module Name: uteval - Object evaluation
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acnamesp.h"
47 
48 #define _COMPONENT          ACPI_UTILITIES
49 ACPI_MODULE_NAME("uteval")
50 
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_ut_evaluate_object
54  *
55  * PARAMETERS:  prefix_node         - Starting node
56  *              path                - Path to object from starting node
57  *              expected_return_types - Bitmap of allowed return types
58  *              return_desc         - Where a return value is stored
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Evaluates a namespace object and verifies the type of the
63  *              return object. Common code that simplifies accessing objects
64  *              that have required return objects of fixed types.
65  *
66  *              NOTE: Internal function, no parameter validation
67  *
68  ******************************************************************************/
69 
70 acpi_status
71 acpi_ut_evaluate_object(struct acpi_namespace_node *prefix_node,
72 			char *path,
73 			u32 expected_return_btypes,
74 			union acpi_operand_object **return_desc)
75 {
76 	struct acpi_evaluate_info *info;
77 	acpi_status status;
78 	u32 return_btype;
79 
80 	ACPI_FUNCTION_TRACE(ut_evaluate_object);
81 
82 	/* Allocate the evaluation information block */
83 
84 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
85 	if (!info) {
86 		return_ACPI_STATUS(AE_NO_MEMORY);
87 	}
88 
89 	info->prefix_node = prefix_node;
90 	info->relative_pathname = path;
91 
92 	/* Evaluate the object/method */
93 
94 	status = acpi_ns_evaluate(info);
95 	if (ACPI_FAILURE(status)) {
96 		if (status == AE_NOT_FOUND) {
97 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
98 					  "[%4.4s.%s] was not found\n",
99 					  acpi_ut_get_node_name(prefix_node),
100 					  path));
101 		} else {
102 			ACPI_ERROR_METHOD("Method execution failed",
103 					  prefix_node, path, status);
104 		}
105 
106 		goto cleanup;
107 	}
108 
109 	/* Did we get a return object? */
110 
111 	if (!info->return_object) {
112 		if (expected_return_btypes) {
113 			ACPI_ERROR_METHOD("No object was returned from",
114 					  prefix_node, path, AE_NOT_EXIST);
115 
116 			status = AE_NOT_EXIST;
117 		}
118 
119 		goto cleanup;
120 	}
121 
122 	/* Map the return object type to the bitmapped type */
123 
124 	switch ((info->return_object)->common.type) {
125 	case ACPI_TYPE_INTEGER:
126 
127 		return_btype = ACPI_BTYPE_INTEGER;
128 		break;
129 
130 	case ACPI_TYPE_BUFFER:
131 
132 		return_btype = ACPI_BTYPE_BUFFER;
133 		break;
134 
135 	case ACPI_TYPE_STRING:
136 
137 		return_btype = ACPI_BTYPE_STRING;
138 		break;
139 
140 	case ACPI_TYPE_PACKAGE:
141 
142 		return_btype = ACPI_BTYPE_PACKAGE;
143 		break;
144 
145 	default:
146 
147 		return_btype = 0;
148 		break;
149 	}
150 
151 	if ((acpi_gbl_enable_interpreter_slack) && (!expected_return_btypes)) {
152 		/*
153 		 * We received a return object, but one was not expected. This can
154 		 * happen frequently if the "implicit return" feature is enabled.
155 		 * Just delete the return object and return AE_OK.
156 		 */
157 		acpi_ut_remove_reference(info->return_object);
158 		goto cleanup;
159 	}
160 
161 	/* Is the return object one of the expected types? */
162 
163 	if (!(expected_return_btypes & return_btype)) {
164 		ACPI_ERROR_METHOD("Return object type is incorrect",
165 				  prefix_node, path, AE_TYPE);
166 
167 		ACPI_ERROR((AE_INFO,
168 			    "Type returned from %s was incorrect: %s, expected Btypes: 0x%X",
169 			    path,
170 			    acpi_ut_get_object_type_name(info->return_object),
171 			    expected_return_btypes));
172 
173 		/* On error exit, we must delete the return object */
174 
175 		acpi_ut_remove_reference(info->return_object);
176 		status = AE_TYPE;
177 		goto cleanup;
178 	}
179 
180 	/* Object type is OK, return it */
181 
182 	*return_desc = info->return_object;
183 
184 cleanup:
185 	ACPI_FREE(info);
186 	return_ACPI_STATUS(status);
187 }
188 
189 /*******************************************************************************
190  *
191  * FUNCTION:    acpi_ut_evaluate_numeric_object
192  *
193  * PARAMETERS:  object_name         - Object name to be evaluated
194  *              device_node         - Node for the device
195  *              value               - Where the value is returned
196  *
197  * RETURN:      Status
198  *
199  * DESCRIPTION: Evaluates a numeric namespace object for a selected device
200  *              and stores result in *Value.
201  *
202  *              NOTE: Internal function, no parameter validation
203  *
204  ******************************************************************************/
205 
206 acpi_status
207 acpi_ut_evaluate_numeric_object(char *object_name,
208 				struct acpi_namespace_node *device_node,
209 				u64 *value)
210 {
211 	union acpi_operand_object *obj_desc;
212 	acpi_status status;
213 
214 	ACPI_FUNCTION_TRACE(ut_evaluate_numeric_object);
215 
216 	status = acpi_ut_evaluate_object(device_node, object_name,
217 					 ACPI_BTYPE_INTEGER, &obj_desc);
218 	if (ACPI_FAILURE(status)) {
219 		return_ACPI_STATUS(status);
220 	}
221 
222 	/* Get the returned Integer */
223 
224 	*value = obj_desc->integer.value;
225 
226 	/* On exit, we must delete the return object */
227 
228 	acpi_ut_remove_reference(obj_desc);
229 	return_ACPI_STATUS(status);
230 }
231 
232 /*******************************************************************************
233  *
234  * FUNCTION:    acpi_ut_execute_STA
235  *
236  * PARAMETERS:  device_node         - Node for the device
237  *              flags               - Where the status flags are returned
238  *
239  * RETURN:      Status
240  *
241  * DESCRIPTION: Executes _STA for selected device and stores results in
242  *              *Flags. If _STA does not exist, then the device is assumed
243  *              to be present/functional/enabled (as per the ACPI spec).
244  *
245  *              NOTE: Internal function, no parameter validation
246  *
247  ******************************************************************************/
248 
249 acpi_status
250 acpi_ut_execute_STA(struct acpi_namespace_node *device_node, u32 * flags)
251 {
252 	union acpi_operand_object *obj_desc;
253 	acpi_status status;
254 
255 	ACPI_FUNCTION_TRACE(ut_execute_STA);
256 
257 	status = acpi_ut_evaluate_object(device_node, METHOD_NAME__STA,
258 					 ACPI_BTYPE_INTEGER, &obj_desc);
259 	if (ACPI_FAILURE(status)) {
260 		if (AE_NOT_FOUND == status) {
261 			/*
262 			 * if _STA does not exist, then (as per the ACPI specification),
263 			 * the returned flags will indicate that the device is present,
264 			 * functional, and enabled.
265 			 */
266 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
267 					  "_STA on %4.4s was not found, assuming device is present\n",
268 					  acpi_ut_get_node_name(device_node)));
269 
270 			*flags = ACPI_UINT32_MAX;
271 			status = AE_OK;
272 		}
273 
274 		return_ACPI_STATUS(status);
275 	}
276 
277 	/* Extract the status flags */
278 
279 	*flags = (u32) obj_desc->integer.value;
280 
281 	/* On exit, we must delete the return object */
282 
283 	acpi_ut_remove_reference(obj_desc);
284 	return_ACPI_STATUS(status);
285 }
286 
287 /*******************************************************************************
288  *
289  * FUNCTION:    acpi_ut_execute_power_methods
290  *
291  * PARAMETERS:  device_node         - Node for the device
292  *              method_names        - Array of power method names
293  *              method_count        - Number of methods to execute
294  *              out_values          - Where the power method values are returned
295  *
296  * RETURN:      Status, out_values
297  *
298  * DESCRIPTION: Executes the specified power methods for the device and returns
299  *              the result(s).
300  *
301  *              NOTE: Internal function, no parameter validation
302  *
303 ******************************************************************************/
304 
305 acpi_status
306 acpi_ut_execute_power_methods(struct acpi_namespace_node *device_node,
307 			      const char **method_names,
308 			      u8 method_count, u8 *out_values)
309 {
310 	union acpi_operand_object *obj_desc;
311 	acpi_status status;
312 	acpi_status final_status = AE_NOT_FOUND;
313 	u32 i;
314 
315 	ACPI_FUNCTION_TRACE(ut_execute_power_methods);
316 
317 	for (i = 0; i < method_count; i++) {
318 		/*
319 		 * Execute the power method (_sx_d or _sx_w). The only allowable
320 		 * return type is an Integer.
321 		 */
322 		status = acpi_ut_evaluate_object(device_node,
323 						 ACPI_CAST_PTR(char,
324 							       method_names[i]),
325 						 ACPI_BTYPE_INTEGER, &obj_desc);
326 		if (ACPI_SUCCESS(status)) {
327 			out_values[i] = (u8)obj_desc->integer.value;
328 
329 			/* Delete the return object */
330 
331 			acpi_ut_remove_reference(obj_desc);
332 			final_status = AE_OK;	/* At least one value is valid */
333 			continue;
334 		}
335 
336 		out_values[i] = ACPI_UINT8_MAX;
337 		if (status == AE_NOT_FOUND) {
338 			continue;	/* Ignore if not found */
339 		}
340 
341 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
342 				  "Failed %s on Device %4.4s, %s\n",
343 				  ACPI_CAST_PTR(char, method_names[i]),
344 				  acpi_ut_get_node_name(device_node),
345 				  acpi_format_exception(status)));
346 	}
347 
348 	return_ACPI_STATUS(final_status);
349 }
350