On Tue, Nov 06, 2007 at 02:33:53AM -0800, akpm@linux-foundation.org wrote:
[mmotm.git] / drivers / acpi / utils.c
blob811fec10462b7f41b89bcc0735b3b99c1819a6b3
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 #include "internal.h"
35 #define _COMPONENT ACPI_BUS_COMPONENT
36 ACPI_MODULE_NAME("utils");
38 /* --------------------------------------------------------------------------
39 Object Evaluation Helpers
40 -------------------------------------------------------------------------- */
41 static void
42 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
44 #ifdef ACPI_DEBUG_OUTPUT
45 char prefix[80] = {'\0'};
46 struct acpi_buffer buffer = {sizeof(prefix), prefix};
47 acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
48 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
49 (char *) prefix, p, acpi_format_exception(s)));
50 #else
51 return;
52 #endif
55 acpi_status
56 acpi_extract_package(union acpi_object *package,
57 struct acpi_buffer *format, struct acpi_buffer *buffer)
59 u32 size_required = 0;
60 u32 tail_offset = 0;
61 char *format_string = NULL;
62 u32 format_count = 0;
63 u32 i = 0;
64 u8 *head = NULL;
65 u8 *tail = NULL;
68 if (!package || (package->type != ACPI_TYPE_PACKAGE)
69 || (package->package.count < 1)) {
70 printk(KERN_WARNING PREFIX "Invalid package argument\n");
71 return AE_BAD_PARAMETER;
74 if (!format || !format->pointer || (format->length < 1)) {
75 printk(KERN_WARNING PREFIX "Invalid format argument\n");
76 return AE_BAD_PARAMETER;
79 if (!buffer) {
80 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
81 return AE_BAD_PARAMETER;
84 format_count = (format->length / sizeof(char)) - 1;
85 if (format_count > package->package.count) {
86 printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
87 " than exist in package [%d].\n",
88 format_count, package->package.count);
89 return AE_BAD_DATA;
92 format_string = format->pointer;
95 * Calculate size_required.
97 for (i = 0; i < format_count; i++) {
99 union acpi_object *element = &(package->package.elements[i]);
101 if (!element) {
102 return AE_BAD_DATA;
105 switch (element->type) {
107 case ACPI_TYPE_INTEGER:
108 switch (format_string[i]) {
109 case 'N':
110 size_required += sizeof(acpi_integer);
111 tail_offset += sizeof(acpi_integer);
112 break;
113 case 'S':
114 size_required +=
115 sizeof(char *) + sizeof(acpi_integer) +
116 sizeof(char);
117 tail_offset += sizeof(char *);
118 break;
119 default:
120 printk(KERN_WARNING PREFIX "Invalid package element"
121 " [%d]: got number, expecing"
122 " [%c]\n",
123 i, format_string[i]);
124 return AE_BAD_DATA;
125 break;
127 break;
129 case ACPI_TYPE_STRING:
130 case ACPI_TYPE_BUFFER:
131 switch (format_string[i]) {
132 case 'S':
133 size_required +=
134 sizeof(char *) +
135 (element->string.length * sizeof(char)) +
136 sizeof(char);
137 tail_offset += sizeof(char *);
138 break;
139 case 'B':
140 size_required +=
141 sizeof(u8 *) +
142 (element->buffer.length * sizeof(u8));
143 tail_offset += sizeof(u8 *);
144 break;
145 default:
146 printk(KERN_WARNING PREFIX "Invalid package element"
147 " [%d] got string/buffer,"
148 " expecing [%c]\n",
149 i, format_string[i]);
150 return AE_BAD_DATA;
151 break;
153 break;
155 case ACPI_TYPE_PACKAGE:
156 default:
157 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
158 "Found unsupported element at index=%d\n",
159 i));
160 /* TBD: handle nested packages... */
161 return AE_SUPPORT;
162 break;
167 * Validate output buffer.
169 if (buffer->length < size_required) {
170 buffer->length = size_required;
171 return AE_BUFFER_OVERFLOW;
172 } else if (buffer->length != size_required || !buffer->pointer) {
173 return AE_BAD_PARAMETER;
176 head = buffer->pointer;
177 tail = buffer->pointer + tail_offset;
180 * Extract package data.
182 for (i = 0; i < format_count; i++) {
184 u8 **pointer = NULL;
185 union acpi_object *element = &(package->package.elements[i]);
187 if (!element) {
188 return AE_BAD_DATA;
191 switch (element->type) {
193 case ACPI_TYPE_INTEGER:
194 switch (format_string[i]) {
195 case 'N':
196 *((acpi_integer *) head) =
197 element->integer.value;
198 head += sizeof(acpi_integer);
199 break;
200 case 'S':
201 pointer = (u8 **) head;
202 *pointer = tail;
203 *((acpi_integer *) tail) =
204 element->integer.value;
205 head += sizeof(acpi_integer *);
206 tail += sizeof(acpi_integer);
207 /* NULL terminate string */
208 *tail = (char)0;
209 tail += sizeof(char);
210 break;
211 default:
212 /* Should never get here */
213 break;
215 break;
217 case ACPI_TYPE_STRING:
218 case ACPI_TYPE_BUFFER:
219 switch (format_string[i]) {
220 case 'S':
221 pointer = (u8 **) head;
222 *pointer = tail;
223 memcpy(tail, element->string.pointer,
224 element->string.length);
225 head += sizeof(char *);
226 tail += element->string.length * sizeof(char);
227 /* NULL terminate string */
228 *tail = (char)0;
229 tail += sizeof(char);
230 break;
231 case 'B':
232 pointer = (u8 **) head;
233 *pointer = tail;
234 memcpy(tail, element->buffer.pointer,
235 element->buffer.length);
236 head += sizeof(u8 *);
237 tail += element->buffer.length * sizeof(u8);
238 break;
239 default:
240 /* Should never get here */
241 break;
243 break;
245 case ACPI_TYPE_PACKAGE:
246 /* TBD: handle nested packages... */
247 default:
248 /* Should never get here */
249 break;
253 return AE_OK;
256 EXPORT_SYMBOL(acpi_extract_package);
258 acpi_status
259 acpi_evaluate_integer(acpi_handle handle,
260 acpi_string pathname,
261 struct acpi_object_list *arguments, unsigned long long *data)
263 acpi_status status = AE_OK;
264 union acpi_object element;
265 struct acpi_buffer buffer = { 0, NULL };
267 if (!data)
268 return AE_BAD_PARAMETER;
270 buffer.length = sizeof(union acpi_object);
271 buffer.pointer = &element;
272 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
273 if (ACPI_FAILURE(status)) {
274 acpi_util_eval_error(handle, pathname, status);
275 return status;
278 if (element.type != ACPI_TYPE_INTEGER) {
279 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
280 return AE_BAD_DATA;
283 *data = element.integer.value;
285 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
287 return AE_OK;
290 EXPORT_SYMBOL(acpi_evaluate_integer);
292 #if 0
293 acpi_status
294 acpi_evaluate_string(acpi_handle handle,
295 acpi_string pathname,
296 acpi_object_list * arguments, acpi_string * data)
298 acpi_status status = AE_OK;
299 acpi_object *element = NULL;
300 acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
303 if (!data)
304 return AE_BAD_PARAMETER;
306 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
307 if (ACPI_FAILURE(status)) {
308 acpi_util_eval_error(handle, pathname, status);
309 return status;
312 element = (acpi_object *) buffer.pointer;
314 if ((element->type != ACPI_TYPE_STRING)
315 || (element->type != ACPI_TYPE_BUFFER)
316 || !element->string.length) {
317 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
318 return AE_BAD_DATA;
321 *data = kzalloc(element->string.length + 1, GFP_KERNEL);
322 if (!data) {
323 printk(KERN_ERR PREFIX "Memory allocation\n");
324 return -ENOMEM;
327 memcpy(*data, element->string.pointer, element->string.length);
329 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data));
331 kfree(buffer.pointer);
333 return AE_OK;
335 #endif
337 acpi_status
338 acpi_evaluate_reference(acpi_handle handle,
339 acpi_string pathname,
340 struct acpi_object_list *arguments,
341 struct acpi_handle_list *list)
343 acpi_status status = AE_OK;
344 union acpi_object *package = NULL;
345 union acpi_object *element = NULL;
346 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
347 u32 i = 0;
350 if (!list) {
351 return AE_BAD_PARAMETER;
354 /* Evaluate object. */
356 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
357 if (ACPI_FAILURE(status))
358 goto end;
360 package = buffer.pointer;
362 if ((buffer.length == 0) || !package) {
363 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
364 (unsigned)buffer.length, package);
365 status = AE_BAD_DATA;
366 acpi_util_eval_error(handle, pathname, status);
367 goto end;
369 if (package->type != ACPI_TYPE_PACKAGE) {
370 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
371 package->type);
372 status = AE_BAD_DATA;
373 acpi_util_eval_error(handle, pathname, status);
374 goto end;
376 if (!package->package.count) {
377 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
378 package);
379 status = AE_BAD_DATA;
380 acpi_util_eval_error(handle, pathname, status);
381 goto end;
384 if (package->package.count > ACPI_MAX_HANDLES) {
385 return AE_NO_MEMORY;
387 list->count = package->package.count;
389 /* Extract package data. */
391 for (i = 0; i < list->count; i++) {
393 element = &(package->package.elements[i]);
395 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
396 status = AE_BAD_DATA;
397 printk(KERN_ERR PREFIX
398 "Expecting a [Reference] package element, found type %X\n",
399 element->type);
400 acpi_util_eval_error(handle, pathname, status);
401 break;
404 if (!element->reference.handle) {
405 printk(KERN_WARNING PREFIX "Invalid reference in"
406 " package %s\n", pathname);
407 status = AE_NULL_ENTRY;
408 break;
410 /* Get the acpi_handle. */
412 list->handles[i] = element->reference.handle;
413 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
414 list->handles[i]));
417 end:
418 if (ACPI_FAILURE(status)) {
419 list->count = 0;
420 //kfree(list->handles);
423 kfree(buffer.pointer);
425 return status;
428 EXPORT_SYMBOL(acpi_evaluate_reference);