xref: /openbmc/linux/drivers/acpi/acpica/uteval.c (revision 3213486f)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: uteval - Object evaluation
5  *
6  * Copyright (C) 2000 - 2019, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acnamesp.h"
13 
14 #define _COMPONENT          ACPI_UTILITIES
15 ACPI_MODULE_NAME("uteval")
16 
17 /*******************************************************************************
18  *
19  * FUNCTION:    acpi_ut_evaluate_object
20  *
21  * PARAMETERS:  prefix_node         - Starting node
22  *              path                - Path to object from starting node
23  *              expected_return_types - Bitmap of allowed return types
24  *              return_desc         - Where a return value is stored
25  *
26  * RETURN:      Status
27  *
28  * DESCRIPTION: Evaluates a namespace object and verifies the type of the
29  *              return object. Common code that simplifies accessing objects
30  *              that have required return objects of fixed types.
31  *
32  *              NOTE: Internal function, no parameter validation
33  *
34  ******************************************************************************/
35 
36 acpi_status
37 acpi_ut_evaluate_object(struct acpi_namespace_node *prefix_node,
38 			const char *path,
39 			u32 expected_return_btypes,
40 			union acpi_operand_object **return_desc)
41 {
42 	struct acpi_evaluate_info *info;
43 	acpi_status status;
44 	u32 return_btype;
45 
46 	ACPI_FUNCTION_TRACE(ut_evaluate_object);
47 
48 	/* Allocate the evaluation information block */
49 
50 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
51 	if (!info) {
52 		return_ACPI_STATUS(AE_NO_MEMORY);
53 	}
54 
55 	info->prefix_node = prefix_node;
56 	info->relative_pathname = path;
57 
58 	/* Evaluate the object/method */
59 
60 	status = acpi_ns_evaluate(info);
61 	if (ACPI_FAILURE(status)) {
62 		if (status == AE_NOT_FOUND) {
63 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
64 					  "[%4.4s.%s] was not found\n",
65 					  acpi_ut_get_node_name(prefix_node),
66 					  path));
67 		} else {
68 			ACPI_ERROR_METHOD("Method execution failed",
69 					  prefix_node, path, status);
70 		}
71 
72 		goto cleanup;
73 	}
74 
75 	/* Did we get a return object? */
76 
77 	if (!info->return_object) {
78 		if (expected_return_btypes) {
79 			ACPI_ERROR_METHOD("No object was returned from",
80 					  prefix_node, path, AE_NOT_EXIST);
81 
82 			status = AE_NOT_EXIST;
83 		}
84 
85 		goto cleanup;
86 	}
87 
88 	/* Map the return object type to the bitmapped type */
89 
90 	switch ((info->return_object)->common.type) {
91 	case ACPI_TYPE_INTEGER:
92 
93 		return_btype = ACPI_BTYPE_INTEGER;
94 		break;
95 
96 	case ACPI_TYPE_BUFFER:
97 
98 		return_btype = ACPI_BTYPE_BUFFER;
99 		break;
100 
101 	case ACPI_TYPE_STRING:
102 
103 		return_btype = ACPI_BTYPE_STRING;
104 		break;
105 
106 	case ACPI_TYPE_PACKAGE:
107 
108 		return_btype = ACPI_BTYPE_PACKAGE;
109 		break;
110 
111 	default:
112 
113 		return_btype = 0;
114 		break;
115 	}
116 
117 	if ((acpi_gbl_enable_interpreter_slack) && (!expected_return_btypes)) {
118 		/*
119 		 * We received a return object, but one was not expected. This can
120 		 * happen frequently if the "implicit return" feature is enabled.
121 		 * Just delete the return object and return AE_OK.
122 		 */
123 		acpi_ut_remove_reference(info->return_object);
124 		goto cleanup;
125 	}
126 
127 	/* Is the return object one of the expected types? */
128 
129 	if (!(expected_return_btypes & return_btype)) {
130 		ACPI_ERROR_METHOD("Return object type is incorrect",
131 				  prefix_node, path, AE_TYPE);
132 
133 		ACPI_ERROR((AE_INFO,
134 			    "Type returned from %s was incorrect: %s, expected Btypes: 0x%X",
135 			    path,
136 			    acpi_ut_get_object_type_name(info->return_object),
137 			    expected_return_btypes));
138 
139 		/* On error exit, we must delete the return object */
140 
141 		acpi_ut_remove_reference(info->return_object);
142 		status = AE_TYPE;
143 		goto cleanup;
144 	}
145 
146 	/* Object type is OK, return it */
147 
148 	*return_desc = info->return_object;
149 
150 cleanup:
151 	ACPI_FREE(info);
152 	return_ACPI_STATUS(status);
153 }
154 
155 /*******************************************************************************
156  *
157  * FUNCTION:    acpi_ut_evaluate_numeric_object
158  *
159  * PARAMETERS:  object_name         - Object name to be evaluated
160  *              device_node         - Node for the device
161  *              value               - Where the value is returned
162  *
163  * RETURN:      Status
164  *
165  * DESCRIPTION: Evaluates a numeric namespace object for a selected device
166  *              and stores result in *Value.
167  *
168  *              NOTE: Internal function, no parameter validation
169  *
170  ******************************************************************************/
171 
172 acpi_status
173 acpi_ut_evaluate_numeric_object(const char *object_name,
174 				struct acpi_namespace_node *device_node,
175 				u64 *value)
176 {
177 	union acpi_operand_object *obj_desc;
178 	acpi_status status;
179 
180 	ACPI_FUNCTION_TRACE(ut_evaluate_numeric_object);
181 
182 	status = acpi_ut_evaluate_object(device_node, object_name,
183 					 ACPI_BTYPE_INTEGER, &obj_desc);
184 	if (ACPI_FAILURE(status)) {
185 		return_ACPI_STATUS(status);
186 	}
187 
188 	/* Get the returned Integer */
189 
190 	*value = obj_desc->integer.value;
191 
192 	/* On exit, we must delete the return object */
193 
194 	acpi_ut_remove_reference(obj_desc);
195 	return_ACPI_STATUS(status);
196 }
197 
198 /*******************************************************************************
199  *
200  * FUNCTION:    acpi_ut_execute_STA
201  *
202  * PARAMETERS:  device_node         - Node for the device
203  *              flags               - Where the status flags are returned
204  *
205  * RETURN:      Status
206  *
207  * DESCRIPTION: Executes _STA for selected device and stores results in
208  *              *Flags. If _STA does not exist, then the device is assumed
209  *              to be present/functional/enabled (as per the ACPI spec).
210  *
211  *              NOTE: Internal function, no parameter validation
212  *
213  ******************************************************************************/
214 
215 acpi_status
216 acpi_ut_execute_STA(struct acpi_namespace_node *device_node, u32 * flags)
217 {
218 	union acpi_operand_object *obj_desc;
219 	acpi_status status;
220 
221 	ACPI_FUNCTION_TRACE(ut_execute_STA);
222 
223 	status = acpi_ut_evaluate_object(device_node, METHOD_NAME__STA,
224 					 ACPI_BTYPE_INTEGER, &obj_desc);
225 	if (ACPI_FAILURE(status)) {
226 		if (AE_NOT_FOUND == status) {
227 			/*
228 			 * if _STA does not exist, then (as per the ACPI specification),
229 			 * the returned flags will indicate that the device is present,
230 			 * functional, and enabled.
231 			 */
232 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
233 					  "_STA on %4.4s was not found, assuming device is present\n",
234 					  acpi_ut_get_node_name(device_node)));
235 
236 			*flags = ACPI_UINT32_MAX;
237 			status = AE_OK;
238 		}
239 
240 		return_ACPI_STATUS(status);
241 	}
242 
243 	/* Extract the status flags */
244 
245 	*flags = (u32) obj_desc->integer.value;
246 
247 	/* On exit, we must delete the return object */
248 
249 	acpi_ut_remove_reference(obj_desc);
250 	return_ACPI_STATUS(status);
251 }
252 
253 /*******************************************************************************
254  *
255  * FUNCTION:    acpi_ut_execute_power_methods
256  *
257  * PARAMETERS:  device_node         - Node for the device
258  *              method_names        - Array of power method names
259  *              method_count        - Number of methods to execute
260  *              out_values          - Where the power method values are returned
261  *
262  * RETURN:      Status, out_values
263  *
264  * DESCRIPTION: Executes the specified power methods for the device and returns
265  *              the result(s).
266  *
267  *              NOTE: Internal function, no parameter validation
268  *
269 ******************************************************************************/
270 
271 acpi_status
272 acpi_ut_execute_power_methods(struct acpi_namespace_node *device_node,
273 			      const char **method_names,
274 			      u8 method_count, u8 *out_values)
275 {
276 	union acpi_operand_object *obj_desc;
277 	acpi_status status;
278 	acpi_status final_status = AE_NOT_FOUND;
279 	u32 i;
280 
281 	ACPI_FUNCTION_TRACE(ut_execute_power_methods);
282 
283 	for (i = 0; i < method_count; i++) {
284 		/*
285 		 * Execute the power method (_sx_d or _sx_w). The only allowable
286 		 * return type is an Integer.
287 		 */
288 		status = acpi_ut_evaluate_object(device_node,
289 						 ACPI_CAST_PTR(char,
290 							       method_names[i]),
291 						 ACPI_BTYPE_INTEGER, &obj_desc);
292 		if (ACPI_SUCCESS(status)) {
293 			out_values[i] = (u8)obj_desc->integer.value;
294 
295 			/* Delete the return object */
296 
297 			acpi_ut_remove_reference(obj_desc);
298 			final_status = AE_OK;	/* At least one value is valid */
299 			continue;
300 		}
301 
302 		out_values[i] = ACPI_UINT8_MAX;
303 		if (status == AE_NOT_FOUND) {
304 			continue;	/* Ignore if not found */
305 		}
306 
307 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
308 				  "Failed %s on Device %4.4s, %s\n",
309 				  ACPI_CAST_PTR(char, method_names[i]),
310 				  acpi_ut_get_node_name(device_node),
311 				  acpi_format_exception(status)));
312 	}
313 
314 	return_ACPI_STATUS(final_status);
315 }
316