?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
MOXA linux-2.6.x / linux-2.6.9-uc0 from sdlinux-moxaart.tgz
[linux-2.6.9-moxart.git] / drivers / acpi / namespace / nsaccess.c
blob765217be42d731fafa1d3f9fe328673ab84330cf
1 /*******************************************************************************
2 *
3 * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2004, R. Byron Moore
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
45 #include <acpi/acpi.h>
46 #include <acpi/amlcode.h>
47 #include <acpi/acnamesp.h>
48 #include <acpi/acdispat.h>
49
50
51 #define _COMPONENT ACPI_NAMESPACE
52 ACPI_MODULE_NAME ("nsaccess")
53
54
55 /*******************************************************************************
56 *
57 * FUNCTION: acpi_ns_root_initialize
58 *
59 * PARAMETERS: None
60 *
61 * RETURN: Status
62 *
63 * DESCRIPTION: Allocate and initialize the default root named objects
64 *
65 * MUTEX: Locks namespace for entire execution
66 *
67 ******************************************************************************/
68
69 acpi_status
70 acpi_ns_root_initialize (void)
71 {
72 acpi_status status;
73 const struct acpi_predefined_names *init_val = NULL;
74 struct acpi_namespace_node *new_node;
75 union acpi_operand_object *obj_desc;
76 acpi_string val = NULL;
77
78
79 ACPI_FUNCTION_TRACE ("ns_root_initialize");
80
81
82 status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
83 if (ACPI_FAILURE (status)) {
84 return_ACPI_STATUS (status);
85 }
86
87 /*
88 * The global root ptr is initially NULL, so a non-NULL value indicates
89 * that acpi_ns_root_initialize() has already been called; just return.
90 */
91 if (acpi_gbl_root_node) {
92 status = AE_OK;
93 goto unlock_and_exit;
94 }
95
96 /*
97 * Tell the rest of the subsystem that the root is initialized
98 * (This is OK because the namespace is locked)
99 */
100 acpi_gbl_root_node = &acpi_gbl_root_node_struct;
101
102 /* Enter the pre-defined names in the name table */
103
104 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
105 "Entering predefined entries into namespace\n"));
106
107 for (init_val = acpi_gbl_pre_defined_names; init_val->name; init_val++) {
108 /* _OSI is optional for now, will be permanent later */
109
110 if (!ACPI_STRCMP (init_val->name, "_OSI") && !acpi_gbl_create_osi_method) {
111 continue;
112 }
113
114 status = acpi_ns_lookup (NULL, init_val->name, init_val->type,
115 ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH,
116 NULL, &new_node);
117
118 if (ACPI_FAILURE (status) || (!new_node)) /* Must be on same line for code converter */ {
119 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
120 "Could not create predefined name %s, %s\n",
121 init_val->name, acpi_format_exception (status)));
122 }
123
124 /*
125 * Name entered successfully.
126 * If entry in pre_defined_names[] specifies an
127 * initial value, create the initial value.
128 */
129 if (init_val->val) {
130 status = acpi_os_predefined_override (init_val, &val);
131 if (ACPI_FAILURE (status)) {
132 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
133 "Could not override predefined %s\n",
134 init_val->name));
135 }
136
137 if (!val) {
138 val = init_val->val;
139 }
140
141 /*
142 * Entry requests an initial value, allocate a
143 * descriptor for it.
144 */
145 obj_desc = acpi_ut_create_internal_object (init_val->type);
146 if (!obj_desc) {
147 status = AE_NO_MEMORY;
148 goto unlock_and_exit;
149 }
150
151 /*
152 * Convert value string from table entry to
153 * internal representation. Only types actually
154 * used for initial values are implemented here.
155 */
156 switch (init_val->type) {
157 case ACPI_TYPE_METHOD:
158 obj_desc->method.param_count = (u8) ACPI_STRTOUL
159 (val, NULL, 10);
160 obj_desc->common.flags |= AOPOBJ_DATA_VALID;
161
162 #if defined (_ACPI_ASL_COMPILER) || defined (_ACPI_DUMP_App)
163
164 /* i_aSL Compiler cheats by putting parameter count in the owner_iD */
165
166 new_node->owner_id = obj_desc->method.param_count;
167 #else
168 /* Mark this as a very SPECIAL method */
169
170 obj_desc->method.method_flags = AML_METHOD_INTERNAL_ONLY;
171 obj_desc->method.implementation = acpi_ut_osi_implementation;
172 #endif
173 break;
174
175 case ACPI_TYPE_INTEGER:
176
177 obj_desc->integer.value =
178 (acpi_integer) ACPI_STRTOUL (val, NULL, 10);
179 break;
180
181
182 case ACPI_TYPE_STRING:
183
184 /*
185 * Build an object around the static string
186 */
187 obj_desc->string.length = (u32) ACPI_STRLEN (val);
188 obj_desc->string.pointer = val;
189 obj_desc->common.flags |= AOPOBJ_STATIC_POINTER;
190 break;
191
192
193 case ACPI_TYPE_MUTEX:
194
195 obj_desc->mutex.node = new_node;
196 obj_desc->mutex.sync_level = (u8) ACPI_STRTOUL
197 (val, NULL, 10);
198
199 if (ACPI_STRCMP (init_val->name, "_GL_") == 0) {
200 /*
201 * Create a counting semaphore for the
202 * global lock
203 */
204 status = acpi_os_create_semaphore (ACPI_NO_UNIT_LIMIT,
205 1, &obj_desc->mutex.semaphore);
206 if (ACPI_FAILURE (status)) {
207 goto unlock_and_exit;
208 }
209
210 /*
211 * We just created the mutex for the
212 * global lock, save it
213 */
214 acpi_gbl_global_lock_semaphore = obj_desc->mutex.semaphore;
215 }
216 else {
217 /* Create a mutex */
218
219 status = acpi_os_create_semaphore (1, 1,
220 &obj_desc->mutex.semaphore);
221 if (ACPI_FAILURE (status)) {
222 goto unlock_and_exit;
223 }
224 }
225 break;
226
227
228 default:
229
230 ACPI_REPORT_ERROR (("Unsupported initial type value %X\n",
231 init_val->type));
232 acpi_ut_remove_reference (obj_desc);
233 obj_desc = NULL;
234 continue;
235 }
236
237 /* Store pointer to value descriptor in the Node */
238
239 status = acpi_ns_attach_object (new_node, obj_desc, ACPI_GET_OBJECT_TYPE (obj_desc));
240
241 /* Remove local reference to the object */
242
243 acpi_ut_remove_reference (obj_desc);
244 }
245 }
246
247
248 unlock_and_exit:
249 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
250
251 /* Save a handle to "_GPE", it is always present */
252
253 if (ACPI_SUCCESS (status)) {
254 status = acpi_ns_get_node_by_path ("\\_GPE", NULL, ACPI_NS_NO_UPSEARCH,
255 &acpi_gbl_fadt_gpe_device);
256 }
257
258 return_ACPI_STATUS (status);
259 }
260
261
262 /*******************************************************************************
263 *
264 * FUNCTION: acpi_ns_lookup
265 *
266 * PARAMETERS: prefix_node - Search scope if name is not fully qualified
267 * Pathname - Search pathname, in internal format
268 * (as represented in the AML stream)
269 * Type - Type associated with name
270 * interpreter_mode - IMODE_LOAD_PASS2 => add name if not found
271 * Flags - Flags describing the search restrictions
272 * walk_state - Current state of the walk
273 * return_node - Where the Node is placed (if found
274 * or created successfully)
275 *
276 * RETURN: Status
277 *
278 * DESCRIPTION: Find or enter the passed name in the name space.
279 * Log an error if name not found in Exec mode.
280 *
281 * MUTEX: Assumes namespace is locked.
282 *
283 ******************************************************************************/
284
285 acpi_status
286 acpi_ns_lookup (
287 union acpi_generic_state *scope_info,
288 char *pathname,
289 acpi_object_type type,
290 acpi_interpreter_mode interpreter_mode,
291 u32 flags,
292 struct acpi_walk_state *walk_state,
293 struct acpi_namespace_node **return_node)
294 {
295 acpi_status status;
296 char *path = pathname;
297 struct acpi_namespace_node *prefix_node;
298 struct acpi_namespace_node *current_node = NULL;
299 struct acpi_namespace_node *this_node = NULL;
300 u32 num_segments;
301 u32 num_carats;
302 acpi_name simple_name;
303 acpi_object_type type_to_check_for;
304 acpi_object_type this_search_type;
305 u32 search_parent_flag = ACPI_NS_SEARCH_PARENT;
306 u32 local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND |
307 ACPI_NS_SEARCH_PARENT);
308
309
310 ACPI_FUNCTION_TRACE ("ns_lookup");
311
312
313 if (!return_node) {
314 return_ACPI_STATUS (AE_BAD_PARAMETER);
315 }
316
317 acpi_gbl_ns_lookup_count++;
318 *return_node = ACPI_ENTRY_NOT_FOUND;
319
320 if (!acpi_gbl_root_node) {
321 return_ACPI_STATUS (AE_NO_NAMESPACE);
322 }
323
324 /*
325 * Get the prefix scope.
326 * A null scope means use the root scope
327 */
328 if ((!scope_info) ||
329 (!scope_info->scope.node)) {
330 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
331 "Null scope prefix, using root node (%p)\n",
332 acpi_gbl_root_node));
333
334 prefix_node = acpi_gbl_root_node;
335 }
336 else {
337 prefix_node = scope_info->scope.node;
338 if (ACPI_GET_DESCRIPTOR_TYPE (prefix_node) != ACPI_DESC_TYPE_NAMED) {
339 ACPI_REPORT_ERROR (("ns_lookup: %p is not a namespace node [%s]\n",
340 prefix_node, acpi_ut_get_descriptor_name (prefix_node)));
341 return_ACPI_STATUS (AE_AML_INTERNAL);
342 }
343
344 /*
345 * This node might not be a actual "scope" node (such as a
346 * Device/Method, etc.) It could be a Package or other object node.
347 * Backup up the tree to find the containing scope node.
348 */
349 while (!acpi_ns_opens_scope (prefix_node->type) &&
350 prefix_node->type != ACPI_TYPE_ANY) {
351 prefix_node = acpi_ns_get_parent_node (prefix_node);
352 }
353 }
354
355 /* Save type TBD: may be no longer necessary */
356
357 type_to_check_for = type;
358
359 /*
360 * Begin examination of the actual pathname
361 */
362 if (!pathname) {
363 /* A Null name_path is allowed and refers to the root */
364
365 num_segments = 0;
366 this_node = acpi_gbl_root_node;
367 path = "";
368
369 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
370 "Null Pathname (Zero segments), Flags=%X\n", flags));
371 }
372 else {
373 /*
374 * Name pointer is valid (and must be in internal name format)
375 *
376 * Check for scope prefixes:
377 *
378 * As represented in the AML stream, a namepath consists of an
379 * optional scope prefix followed by a name segment part.
380 *
381 * If present, the scope prefix is either a Root Prefix (in
382 * which case the name is fully qualified), or one or more
383 * Parent Prefixes (in which case the name's scope is relative
384 * to the current scope).
385 */
386 if (*path == (u8) AML_ROOT_PREFIX) {
387 /* Pathname is fully qualified, start from the root */
388
389 this_node = acpi_gbl_root_node;
390 search_parent_flag = ACPI_NS_NO_UPSEARCH;
391
392 /* Point to name segment part */
393
394 path++;
395
396 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
397 "Path is absolute from root [%p]\n", this_node));
398 }
399 else {
400 /* Pathname is relative to current scope, start there */
401
402 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
403 "Searching relative to prefix scope [%4.4s] (%p)\n",
404 acpi_ut_get_node_name (prefix_node), prefix_node));
405
406 /*
407 * Handle multiple Parent Prefixes (carat) by just getting
408 * the parent node for each prefix instance.
409 */
410 this_node = prefix_node;
411 num_carats = 0;
412 while (*path == (u8) AML_PARENT_PREFIX) {
413 /* Name is fully qualified, no search rules apply */
414
415 search_parent_flag = ACPI_NS_NO_UPSEARCH;
416 /*
417 * Point past this prefix to the name segment
418 * part or the next Parent Prefix
419 */
420 path++;
421
422 /* Backup to the parent node */
423
424 num_carats++;
425 this_node = acpi_ns_get_parent_node (this_node);
426 if (!this_node) {
427 /* Current scope has no parent scope */
428
429 ACPI_REPORT_ERROR (
430 ("ACPI path has too many parent prefixes (^) - reached beyond root node\n"));
431 return_ACPI_STATUS (AE_NOT_FOUND);
432 }
433 }
434
435 if (search_parent_flag == ACPI_NS_NO_UPSEARCH) {
436 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
437 "Search scope is [%4.4s], path has %d carat(s)\n",
438 acpi_ut_get_node_name (this_node), num_carats));
439 }
440 }
441
442 /*
443 * Determine the number of ACPI name segments in this pathname.
444 *
445 * The segment part consists of either:
446 * - A Null name segment (0)
447 * - A dual_name_prefix followed by two 4-byte name segments
448 * - A multi_name_prefix followed by a byte indicating the
449 * number of segments and the segments themselves.
450 * - A single 4-byte name segment
451 *
452 * Examine the name prefix opcode, if any, to determine the number of
453 * segments.
454 */
455 switch (*path) {
456 case 0:
457 /*
458 * Null name after a root or parent prefixes. We already
459 * have the correct target node and there are no name segments.
460 */
461 num_segments = 0;
462 type = this_node->type;
463
464 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
465 "Prefix-only Pathname (Zero name segments), Flags=%X\n", flags));
466 break;
467
468 case AML_DUAL_NAME_PREFIX:
469
470 /* More than one name_seg, search rules do not apply */
471
472 search_parent_flag = ACPI_NS_NO_UPSEARCH;
473
474 /* Two segments, point to first name segment */
475
476 num_segments = 2;
477 path++;
478
479 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
480 "Dual Pathname (2 segments, Flags=%X)\n", flags));
481 break;
482
483 case AML_MULTI_NAME_PREFIX_OP:
484
485 /* More than one name_seg, search rules do not apply */
486
487 search_parent_flag = ACPI_NS_NO_UPSEARCH;
488
489 /* Extract segment count, point to first name segment */
490
491 path++;
492 num_segments = (u32) (u8) *path;
493 path++;
494
495 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
496 "Multi Pathname (%d Segments, Flags=%X) \n",
497 num_segments, flags));
498 break;
499
500 default:
501 /*
502 * Not a Null name, no Dual or Multi prefix, hence there is
503 * only one name segment and Pathname is already pointing to it.
504 */
505 num_segments = 1;
506
507 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
508 "Simple Pathname (1 segment, Flags=%X)\n", flags));
509 break;
510 }
511
512 ACPI_DEBUG_EXEC (acpi_ns_print_pathname (num_segments, path));
513 }
514
515
516 /*
517 * Search namespace for each segment of the name. Loop through and
518 * verify (or add to the namespace) each name segment.
519 *
520 * The object type is significant only at the last name
521 * segment. (We don't care about the types along the path, only
522 * the type of the final target object.)
523 */
524 this_search_type = ACPI_TYPE_ANY;
525 current_node = this_node;
526 while (num_segments && current_node) {
527 num_segments--;
528 if (!num_segments) {
529 /*
530 * This is the last segment, enable typechecking
531 */
532 this_search_type = type;
533
534 /*
535 * Only allow automatic parent search (search rules) if the caller
536 * requested it AND we have a single, non-fully-qualified name_seg
537 */
538 if ((search_parent_flag != ACPI_NS_NO_UPSEARCH) &&
539 (flags & ACPI_NS_SEARCH_PARENT)) {
540 local_flags |= ACPI_NS_SEARCH_PARENT;
541 }
542
543 /* Set error flag according to caller */
544
545 if (flags & ACPI_NS_ERROR_IF_FOUND) {
546 local_flags |= ACPI_NS_ERROR_IF_FOUND;
547 }
548 }
549
550 /* Extract one ACPI name from the front of the pathname */
551
552 ACPI_MOVE_32_TO_32 (&simple_name, path);
553
554 /* Try to find the single (4 character) ACPI name */
555
556 status = acpi_ns_search_and_enter (simple_name, walk_state, current_node,
557 interpreter_mode, this_search_type, local_flags, &this_node);
558 if (ACPI_FAILURE (status)) {
559 if (status == AE_NOT_FOUND) {
560 /* Name not found in ACPI namespace */
561
562 ACPI_DEBUG_PRINT ((ACPI_DB_NAMES,
563 "Name [%4.4s] not found in scope [%4.4s] %p\n",
564 (char *) &simple_name, (char *) &current_node->name,
565 current_node));
566 }
567
568 *return_node = this_node;
569 return_ACPI_STATUS (status);
570 }
571
572 /*
573 * Sanity typecheck of the target object:
574 *
575 * If 1) This is the last segment (num_segments == 0)
576 * 2) And we are looking for a specific type
577 * (Not checking for TYPE_ANY)
578 * 3) Which is not an alias
579 * 4) Which is not a local type (TYPE_SCOPE)
580 * 5) And the type of target object is known (not TYPE_ANY)
581 * 6) And target object does not match what we are looking for
582 *
583 * Then we have a type mismatch. Just warn and ignore it.
584 */
585 if ((num_segments == 0) &&
586 (type_to_check_for != ACPI_TYPE_ANY) &&
587 (type_to_check_for != ACPI_TYPE_LOCAL_ALIAS) &&
588 (type_to_check_for != ACPI_TYPE_LOCAL_METHOD_ALIAS) &&
589 (type_to_check_for != ACPI_TYPE_LOCAL_SCOPE) &&
590 (this_node->type != ACPI_TYPE_ANY) &&
591 (this_node->type != type_to_check_for)) {
592 /* Complain about a type mismatch */
593
594 ACPI_REPORT_WARNING (
595 ("ns_lookup: Type mismatch on %4.4s (%s), searching for (%s)\n",
596 (char *) &simple_name, acpi_ut_get_type_name (this_node->type),
597 acpi_ut_get_type_name (type_to_check_for)));
598 }
599
600 /*
601 * If this is the last name segment and we are not looking for a
602 * specific type, but the type of found object is known, use that type
603 * to see if it opens a scope.
604 */
605 if ((num_segments == 0) && (type == ACPI_TYPE_ANY)) {
606 type = this_node->type;
607 }
608
609 /* Point to next name segment and make this node current */
610
611 path += ACPI_NAME_SIZE;
612 current_node = this_node;
613 }
614
615 /*
616 * Always check if we need to open a new scope
617 */
618 if (!(flags & ACPI_NS_DONT_OPEN_SCOPE) && (walk_state)) {
619 /*
620 * If entry is a type which opens a scope, push the new scope on the
621 * scope stack.
622 */
623 if (acpi_ns_opens_scope (type)) {
624 status = acpi_ds_scope_stack_push (this_node, type, walk_state);
625 if (ACPI_FAILURE (status)) {
626 return_ACPI_STATUS (status);
627 }
628 }
629 }
630
631 *return_node = this_node;
632 return_ACPI_STATUS (AE_OK);
633 }
634
MOXA 2.6.9 from sdlinux-moxaart.tgz