kernel-parameters.txt: document memmap option better
[linux-2.6/zen-sources.git] / drivers / acpi / utils.c
blob44ea60cf21c09c00adc1135394decbb4af2faa1d
1 /*
2 * acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <acpi/acpi_bus.h>
31 #include <acpi/acpi_drivers.h>
33 #define _COMPONENT ACPI_BUS_COMPONENT
34 ACPI_MODULE_NAME("utils");
36 /* --------------------------------------------------------------------------
37 Object Evaluation Helpers
38 -------------------------------------------------------------------------- */
39 static void
40 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
42 #ifdef ACPI_DEBUG_OUTPUT
43 char prefix[80] = {'\0'};
44 struct acpi_buffer buffer = {sizeof(prefix), prefix};
45 acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
46 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
47 (char *) prefix, p, acpi_format_exception(s)));
48 #else
49 return;
50 #endif
53 acpi_status
54 acpi_extract_package(union acpi_object *package,
55 struct acpi_buffer *format, struct acpi_buffer *buffer)
57 u32 size_required = 0;
58 u32 tail_offset = 0;
59 char *format_string = NULL;
60 u32 format_count = 0;
61 u32 i = 0;
62 u8 *head = NULL;
63 u8 *tail = NULL;
66 if (!package || (package->type != ACPI_TYPE_PACKAGE)
67 || (package->package.count < 1)) {
68 printk(KERN_WARNING PREFIX "Invalid package argument\n");
69 return AE_BAD_PARAMETER;
72 if (!format || !format->pointer || (format->length < 1)) {
73 printk(KERN_WARNING PREFIX "Invalid format argument\n");
74 return AE_BAD_PARAMETER;
77 if (!buffer) {
78 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
79 return AE_BAD_PARAMETER;
82 format_count = (format->length / sizeof(char)) - 1;
83 if (format_count > package->package.count) {
84 printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
85 " than exist in package [%d].\n",
86 format_count, package->package.count);
87 return AE_BAD_DATA;
90 format_string = format->pointer;
93 * Calculate size_required.
95 for (i = 0; i < format_count; i++) {
97 union acpi_object *element = &(package->package.elements[i]);
99 if (!element) {
100 return AE_BAD_DATA;
103 switch (element->type) {
105 case ACPI_TYPE_INTEGER:
106 switch (format_string[i]) {
107 case 'N':
108 size_required += sizeof(acpi_integer);
109 tail_offset += sizeof(acpi_integer);
110 break;
111 case 'S':
112 size_required +=
113 sizeof(char *) + sizeof(acpi_integer) +
114 sizeof(char);
115 tail_offset += sizeof(char *);
116 break;
117 default:
118 printk(KERN_WARNING PREFIX "Invalid package element"
119 " [%d]: got number, expecing"
120 " [%c]\n",
121 i, format_string[i]);
122 return AE_BAD_DATA;
123 break;
125 break;
127 case ACPI_TYPE_STRING:
128 case ACPI_TYPE_BUFFER:
129 switch (format_string[i]) {
130 case 'S':
131 size_required +=
132 sizeof(char *) +
133 (element->string.length * sizeof(char)) +
134 sizeof(char);
135 tail_offset += sizeof(char *);
136 break;
137 case 'B':
138 size_required +=
139 sizeof(u8 *) +
140 (element->buffer.length * sizeof(u8));
141 tail_offset += sizeof(u8 *);
142 break;
143 default:
144 printk(KERN_WARNING PREFIX "Invalid package element"
145 " [%d] got string/buffer,"
146 " expecing [%c]\n",
147 i, format_string[i]);
148 return AE_BAD_DATA;
149 break;
151 break;
153 case ACPI_TYPE_PACKAGE:
154 default:
155 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
156 "Found unsupported element at index=%d\n",
157 i));
158 /* TBD: handle nested packages... */
159 return AE_SUPPORT;
160 break;
165 * Validate output buffer.
167 if (buffer->length < size_required) {
168 buffer->length = size_required;
169 return AE_BUFFER_OVERFLOW;
170 } else if (buffer->length != size_required || !buffer->pointer) {
171 return AE_BAD_PARAMETER;
174 head = buffer->pointer;
175 tail = buffer->pointer + tail_offset;
178 * Extract package data.
180 for (i = 0; i < format_count; i++) {
182 u8 **pointer = NULL;
183 union acpi_object *element = &(package->package.elements[i]);
185 if (!element) {
186 return AE_BAD_DATA;
189 switch (element->type) {
191 case ACPI_TYPE_INTEGER:
192 switch (format_string[i]) {
193 case 'N':
194 *((acpi_integer *) head) =
195 element->integer.value;
196 head += sizeof(acpi_integer);
197 break;
198 case 'S':
199 pointer = (u8 **) head;
200 *pointer = tail;
201 *((acpi_integer *) tail) =
202 element->integer.value;
203 head += sizeof(acpi_integer *);
204 tail += sizeof(acpi_integer);
205 /* NULL terminate string */
206 *tail = (char)0;
207 tail += sizeof(char);
208 break;
209 default:
210 /* Should never get here */
211 break;
213 break;
215 case ACPI_TYPE_STRING:
216 case ACPI_TYPE_BUFFER:
217 switch (format_string[i]) {
218 case 'S':
219 pointer = (u8 **) head;
220 *pointer = tail;
221 memcpy(tail, element->string.pointer,
222 element->string.length);
223 head += sizeof(char *);
224 tail += element->string.length * sizeof(char);
225 /* NULL terminate string */
226 *tail = (char)0;
227 tail += sizeof(char);
228 break;
229 case 'B':
230 pointer = (u8 **) head;
231 *pointer = tail;
232 memcpy(tail, element->buffer.pointer,
233 element->buffer.length);
234 head += sizeof(u8 *);
235 tail += element->buffer.length * sizeof(u8);
236 break;
237 default:
238 /* Should never get here */
239 break;
241 break;
243 case ACPI_TYPE_PACKAGE:
244 /* TBD: handle nested packages... */
245 default:
246 /* Should never get here */
247 break;
251 return AE_OK;
254 EXPORT_SYMBOL(acpi_extract_package);
256 acpi_status
257 acpi_evaluate_integer(acpi_handle handle,
258 acpi_string pathname,
259 struct acpi_object_list *arguments, unsigned long *data)
261 acpi_status status = AE_OK;
262 union acpi_object *element;
263 struct acpi_buffer buffer = { 0, NULL };
266 if (!data)
267 return AE_BAD_PARAMETER;
269 element = kzalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
270 if (!element)
271 return AE_NO_MEMORY;
273 buffer.length = sizeof(union acpi_object);
274 buffer.pointer = element;
275 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
276 if (ACPI_FAILURE(status)) {
277 acpi_util_eval_error(handle, pathname, status);
278 kfree(element);
279 return status;
282 if (element->type != ACPI_TYPE_INTEGER) {
283 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
284 kfree(element);
285 return AE_BAD_DATA;
288 *data = element->integer.value;
289 kfree(element);
291 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%lu]\n", *data));
293 return AE_OK;
296 EXPORT_SYMBOL(acpi_evaluate_integer);
298 #if 0
299 acpi_status
300 acpi_evaluate_string(acpi_handle handle,
301 acpi_string pathname,
302 acpi_object_list * arguments, acpi_string * data)
304 acpi_status status = AE_OK;
305 acpi_object *element = NULL;
306 acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
309 if (!data)
310 return AE_BAD_PARAMETER;
312 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
313 if (ACPI_FAILURE(status)) {
314 acpi_util_eval_error(handle, pathname, status);
315 return status;
318 element = (acpi_object *) buffer.pointer;
320 if ((element->type != ACPI_TYPE_STRING)
321 || (element->type != ACPI_TYPE_BUFFER)
322 || !element->string.length) {
323 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
324 return AE_BAD_DATA;
327 *data = kzalloc(element->string.length + 1, GFP_KERNEL);
328 if (!data) {
329 printk(KERN_ERR PREFIX "Memory allocation\n");
330 return -ENOMEM;
333 memcpy(*data, element->string.pointer, element->string.length);
335 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data));
337 kfree(buffer.pointer);
339 return AE_OK;
341 #endif
343 acpi_status
344 acpi_evaluate_reference(acpi_handle handle,
345 acpi_string pathname,
346 struct acpi_object_list *arguments,
347 struct acpi_handle_list *list)
349 acpi_status status = AE_OK;
350 union acpi_object *package = NULL;
351 union acpi_object *element = NULL;
352 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
353 u32 i = 0;
356 if (!list) {
357 return AE_BAD_PARAMETER;
360 /* Evaluate object. */
362 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
363 if (ACPI_FAILURE(status))
364 goto end;
366 package = buffer.pointer;
368 if ((buffer.length == 0) || !package) {
369 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
370 (unsigned)buffer.length, package);
371 status = AE_BAD_DATA;
372 acpi_util_eval_error(handle, pathname, status);
373 goto end;
375 if (package->type != ACPI_TYPE_PACKAGE) {
376 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
377 package->type);
378 status = AE_BAD_DATA;
379 acpi_util_eval_error(handle, pathname, status);
380 goto end;
382 if (!package->package.count) {
383 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
384 package);
385 status = AE_BAD_DATA;
386 acpi_util_eval_error(handle, pathname, status);
387 goto end;
390 if (package->package.count > ACPI_MAX_HANDLES) {
391 return AE_NO_MEMORY;
393 list->count = package->package.count;
395 /* Extract package data. */
397 for (i = 0; i < list->count; i++) {
399 element = &(package->package.elements[i]);
401 if (element->type != ACPI_TYPE_ANY) {
402 status = AE_BAD_DATA;
403 printk(KERN_ERR PREFIX
404 "Expecting a [Reference] package element, found type %X\n",
405 element->type);
406 acpi_util_eval_error(handle, pathname, status);
407 break;
410 if (!element->reference.handle) {
411 printk(KERN_WARNING PREFIX "Invalid reference in"
412 " package %s\n", pathname);
413 status = AE_NULL_ENTRY;
414 break;
416 /* Get the acpi_handle. */
418 list->handles[i] = element->reference.handle;
419 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
420 list->handles[i]));
423 end:
424 if (ACPI_FAILURE(status)) {
425 list->count = 0;
426 //kfree(list->handles);
429 kfree(buffer.pointer);
431 return status;
434 EXPORT_SYMBOL(acpi_evaluate_reference);