xref: /openbmc/linux/drivers/acpi/acpica/nsobject.c (revision d4295e12)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3  *
4  * Module Name: nsobject - Utilities for objects attached to namespace
5  *                         table entries
6  *
7  ******************************************************************************/
8 
9 #include <acpi/acpi.h>
10 #include "accommon.h"
11 #include "acnamesp.h"
12 
13 #define _COMPONENT          ACPI_NAMESPACE
14 ACPI_MODULE_NAME("nsobject")
15 
16 /*******************************************************************************
17  *
18  * FUNCTION:    acpi_ns_attach_object
19  *
20  * PARAMETERS:  node                - Parent Node
21  *              object              - Object to be attached
22  *              type                - Type of object, or ACPI_TYPE_ANY if not
23  *                                    known
24  *
25  * RETURN:      Status
26  *
27  * DESCRIPTION: Record the given object as the value associated with the
28  *              name whose acpi_handle is passed. If Object is NULL
29  *              and Type is ACPI_TYPE_ANY, set the name as having no value.
30  *              Note: Future may require that the Node->Flags field be passed
31  *              as a parameter.
32  *
33  * MUTEX:       Assumes namespace is locked
34  *
35  ******************************************************************************/
36 acpi_status
37 acpi_ns_attach_object(struct acpi_namespace_node *node,
38 		      union acpi_operand_object *object, acpi_object_type type)
39 {
40 	union acpi_operand_object *obj_desc;
41 	union acpi_operand_object *last_obj_desc;
42 	acpi_object_type object_type = ACPI_TYPE_ANY;
43 
44 	ACPI_FUNCTION_TRACE(ns_attach_object);
45 
46 	/*
47 	 * Parameter validation
48 	 */
49 	if (!node) {
50 
51 		/* Invalid handle */
52 
53 		ACPI_ERROR((AE_INFO, "Null NamedObj handle"));
54 		return_ACPI_STATUS(AE_BAD_PARAMETER);
55 	}
56 
57 	if (!object && (ACPI_TYPE_ANY != type)) {
58 
59 		/* Null object */
60 
61 		ACPI_ERROR((AE_INFO,
62 			    "Null object, but type not ACPI_TYPE_ANY"));
63 		return_ACPI_STATUS(AE_BAD_PARAMETER);
64 	}
65 
66 	if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {
67 
68 		/* Not a name handle */
69 
70 		ACPI_ERROR((AE_INFO, "Invalid handle %p [%s]",
71 			    node, acpi_ut_get_descriptor_name(node)));
72 		return_ACPI_STATUS(AE_BAD_PARAMETER);
73 	}
74 
75 	/* Check if this object is already attached */
76 
77 	if (node->object == object) {
78 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
79 				  "Obj %p already installed in NameObj %p\n",
80 				  object, node));
81 
82 		return_ACPI_STATUS(AE_OK);
83 	}
84 
85 	/* If null object, we will just install it */
86 
87 	if (!object) {
88 		obj_desc = NULL;
89 		object_type = ACPI_TYPE_ANY;
90 	}
91 
92 	/*
93 	 * If the source object is a namespace Node with an attached object,
94 	 * we will use that (attached) object
95 	 */
96 	else if ((ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) &&
97 		 ((struct acpi_namespace_node *)object)->object) {
98 		/*
99 		 * Value passed is a name handle and that name has a
100 		 * non-null value. Use that name's value and type.
101 		 */
102 		obj_desc = ((struct acpi_namespace_node *)object)->object;
103 		object_type = ((struct acpi_namespace_node *)object)->type;
104 	}
105 
106 	/*
107 	 * Otherwise, we will use the parameter object, but we must type
108 	 * it first
109 	 */
110 	else {
111 		obj_desc = (union acpi_operand_object *)object;
112 
113 		/* Use the given type */
114 
115 		object_type = type;
116 	}
117 
118 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Installing %p into Node %p [%4.4s]\n",
119 			  obj_desc, node, acpi_ut_get_node_name(node)));
120 
121 	/* Detach an existing attached object if present */
122 
123 	if (node->object) {
124 		acpi_ns_detach_object(node);
125 	}
126 
127 	if (obj_desc) {
128 		/*
129 		 * Must increment the new value's reference count
130 		 * (if it is an internal object)
131 		 */
132 		acpi_ut_add_reference(obj_desc);
133 
134 		/*
135 		 * Handle objects with multiple descriptors - walk
136 		 * to the end of the descriptor list
137 		 */
138 		last_obj_desc = obj_desc;
139 		while (last_obj_desc->common.next_object) {
140 			last_obj_desc = last_obj_desc->common.next_object;
141 		}
142 
143 		/* Install the object at the front of the object list */
144 
145 		last_obj_desc->common.next_object = node->object;
146 	}
147 
148 	node->type = (u8) object_type;
149 	node->object = obj_desc;
150 
151 	return_ACPI_STATUS(AE_OK);
152 }
153 
154 /*******************************************************************************
155  *
156  * FUNCTION:    acpi_ns_detach_object
157  *
158  * PARAMETERS:  node           - A Namespace node whose object will be detached
159  *
160  * RETURN:      None.
161  *
162  * DESCRIPTION: Detach/delete an object associated with a namespace node.
163  *              if the object is an allocated object, it is freed.
164  *              Otherwise, the field is simply cleared.
165  *
166  ******************************************************************************/
167 
168 void acpi_ns_detach_object(struct acpi_namespace_node *node)
169 {
170 	union acpi_operand_object *obj_desc;
171 
172 	ACPI_FUNCTION_TRACE(ns_detach_object);
173 
174 	obj_desc = node->object;
175 
176 	if (!obj_desc || (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
177 		return_VOID;
178 	}
179 
180 	if (node->flags & ANOBJ_ALLOCATED_BUFFER) {
181 
182 		/* Free the dynamic aml buffer */
183 
184 		if (obj_desc->common.type == ACPI_TYPE_METHOD) {
185 			ACPI_FREE(obj_desc->method.aml_start);
186 		}
187 	}
188 
189 	/* Clear the Node entry in all cases */
190 
191 	node->object = NULL;
192 	if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) == ACPI_DESC_TYPE_OPERAND) {
193 
194 		/* Unlink object from front of possible object list */
195 
196 		node->object = obj_desc->common.next_object;
197 
198 		/* Handle possible 2-descriptor object */
199 
200 		if (node->object &&
201 		    (node->object->common.type != ACPI_TYPE_LOCAL_DATA)) {
202 			node->object = node->object->common.next_object;
203 		}
204 
205 		/*
206 		 * Detach the object from any data objects (which are still held by
207 		 * the namespace node)
208 		 */
209 		if (obj_desc->common.next_object &&
210 		    ((obj_desc->common.next_object)->common.type ==
211 		     ACPI_TYPE_LOCAL_DATA)) {
212 			obj_desc->common.next_object = NULL;
213 		}
214 	}
215 
216 	/* Reset the node type to untyped */
217 
218 	node->type = ACPI_TYPE_ANY;
219 
220 	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
221 			  node, acpi_ut_get_node_name(node), obj_desc));
222 
223 	/* Remove one reference on the object (and all subobjects) */
224 
225 	acpi_ut_remove_reference(obj_desc);
226 	return_VOID;
227 }
228 
229 /*******************************************************************************
230  *
231  * FUNCTION:    acpi_ns_get_attached_object
232  *
233  * PARAMETERS:  node             - Namespace node
234  *
235  * RETURN:      Current value of the object field from the Node whose
236  *              handle is passed
237  *
238  * DESCRIPTION: Obtain the object attached to a namespace node.
239  *
240  ******************************************************************************/
241 
242 union acpi_operand_object *acpi_ns_get_attached_object(struct
243 						       acpi_namespace_node
244 						       *node)
245 {
246 	ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);
247 
248 	if (!node) {
249 		ACPI_WARNING((AE_INFO, "Null Node ptr"));
250 		return_PTR(NULL);
251 	}
252 
253 	if (!node->object ||
254 	    ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
255 	     && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
256 		 ACPI_DESC_TYPE_NAMED))
257 	    || ((node->object)->common.type == ACPI_TYPE_LOCAL_DATA)) {
258 		return_PTR(NULL);
259 	}
260 
261 	return_PTR(node->object);
262 }
263 
264 /*******************************************************************************
265  *
266  * FUNCTION:    acpi_ns_get_secondary_object
267  *
268  * PARAMETERS:  node             - Namespace node
269  *
270  * RETURN:      Current value of the object field from the Node whose
271  *              handle is passed.
272  *
273  * DESCRIPTION: Obtain a secondary object associated with a namespace node.
274  *
275  ******************************************************************************/
276 
277 union acpi_operand_object *acpi_ns_get_secondary_object(union
278 							acpi_operand_object
279 							*obj_desc)
280 {
281 	ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);
282 
283 	if ((!obj_desc) ||
284 	    (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) ||
285 	    (!obj_desc->common.next_object) ||
286 	    ((obj_desc->common.next_object)->common.type ==
287 	     ACPI_TYPE_LOCAL_DATA)) {
288 		return_PTR(NULL);
289 	}
290 
291 	return_PTR(obj_desc->common.next_object);
292 }
293 
294 /*******************************************************************************
295  *
296  * FUNCTION:    acpi_ns_attach_data
297  *
298  * PARAMETERS:  node            - Namespace node
299  *              handler         - Handler to be associated with the data
300  *              data            - Data to be attached
301  *
302  * RETURN:      Status
303  *
304  * DESCRIPTION: Low-level attach data. Create and attach a Data object.
305  *
306  ******************************************************************************/
307 
308 acpi_status
309 acpi_ns_attach_data(struct acpi_namespace_node *node,
310 		    acpi_object_handler handler, void *data)
311 {
312 	union acpi_operand_object *prev_obj_desc;
313 	union acpi_operand_object *obj_desc;
314 	union acpi_operand_object *data_desc;
315 
316 	/* We only allow one attachment per handler */
317 
318 	prev_obj_desc = NULL;
319 	obj_desc = node->object;
320 	while (obj_desc) {
321 		if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
322 		    (obj_desc->data.handler == handler)) {
323 			return (AE_ALREADY_EXISTS);
324 		}
325 
326 		prev_obj_desc = obj_desc;
327 		obj_desc = obj_desc->common.next_object;
328 	}
329 
330 	/* Create an internal object for the data */
331 
332 	data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
333 	if (!data_desc) {
334 		return (AE_NO_MEMORY);
335 	}
336 
337 	data_desc->data.handler = handler;
338 	data_desc->data.pointer = data;
339 
340 	/* Install the data object */
341 
342 	if (prev_obj_desc) {
343 		prev_obj_desc->common.next_object = data_desc;
344 	} else {
345 		node->object = data_desc;
346 	}
347 
348 	return (AE_OK);
349 }
350 
351 /*******************************************************************************
352  *
353  * FUNCTION:    acpi_ns_detach_data
354  *
355  * PARAMETERS:  node            - Namespace node
356  *              handler         - Handler associated with the data
357  *
358  * RETURN:      Status
359  *
360  * DESCRIPTION: Low-level detach data. Delete the data node, but the caller
361  *              is responsible for the actual data.
362  *
363  ******************************************************************************/
364 
365 acpi_status
366 acpi_ns_detach_data(struct acpi_namespace_node *node,
367 		    acpi_object_handler handler)
368 {
369 	union acpi_operand_object *obj_desc;
370 	union acpi_operand_object *prev_obj_desc;
371 
372 	prev_obj_desc = NULL;
373 	obj_desc = node->object;
374 	while (obj_desc) {
375 		if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
376 		    (obj_desc->data.handler == handler)) {
377 			if (prev_obj_desc) {
378 				prev_obj_desc->common.next_object =
379 				    obj_desc->common.next_object;
380 			} else {
381 				node->object = obj_desc->common.next_object;
382 			}
383 
384 			acpi_ut_remove_reference(obj_desc);
385 			return (AE_OK);
386 		}
387 
388 		prev_obj_desc = obj_desc;
389 		obj_desc = obj_desc->common.next_object;
390 	}
391 
392 	return (AE_NOT_FOUND);
393 }
394 
395 /*******************************************************************************
396  *
397  * FUNCTION:    acpi_ns_get_attached_data
398  *
399  * PARAMETERS:  node            - Namespace node
400  *              handler         - Handler associated with the data
401  *              data            - Where the data is returned
402  *
403  * RETURN:      Status
404  *
405  * DESCRIPTION: Low level interface to obtain data previously associated with
406  *              a namespace node.
407  *
408  ******************************************************************************/
409 
410 acpi_status
411 acpi_ns_get_attached_data(struct acpi_namespace_node *node,
412 			  acpi_object_handler handler, void **data)
413 {
414 	union acpi_operand_object *obj_desc;
415 
416 	obj_desc = node->object;
417 	while (obj_desc) {
418 		if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
419 		    (obj_desc->data.handler == handler)) {
420 			*data = obj_desc->data.pointer;
421 			return (AE_OK);
422 		}
423 
424 		obj_desc = obj_desc->common.next_object;
425 	}
426 
427 	return (AE_NOT_FOUND);
428 }
429