Merge branch 'docs' of git://git.lwn.net/linux-2.6
[linux-2.6] / drivers / acpi / utils.c
1 /*
2  *  acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
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.
13  *
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.
18  *
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.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
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>
32
33 #define _COMPONENT              ACPI_BUS_COMPONENT
34 ACPI_MODULE_NAME("utils");
35
36 /* --------------------------------------------------------------------------
37                             Object Evaluation Helpers
38    -------------------------------------------------------------------------- */
39 static void
40 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
41 {
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
51 }
52
53 acpi_status
54 acpi_extract_package(union acpi_object *package,
55                      struct acpi_buffer *format, struct acpi_buffer *buffer)
56 {
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;
64
65
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;
70         }
71
72         if (!format || !format->pointer || (format->length < 1)) {
73                 printk(KERN_WARNING PREFIX "Invalid format argument\n");
74                 return AE_BAD_PARAMETER;
75         }
76
77         if (!buffer) {
78                 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
79                 return AE_BAD_PARAMETER;
80         }
81
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;
88         }
89
90         format_string = format->pointer;
91
92         /*
93          * Calculate size_required.
94          */
95         for (i = 0; i < format_count; i++) {
96
97                 union acpi_object *element = &(package->package.elements[i]);
98
99                 if (!element) {
100                         return AE_BAD_DATA;
101                 }
102
103                 switch (element->type) {
104
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;
124                         }
125                         break;
126
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;
150                         }
151                         break;
152
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;
161                 }
162         }
163
164         /*
165          * Validate output buffer.
166          */
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;
172         }
173
174         head = buffer->pointer;
175         tail = buffer->pointer + tail_offset;
176
177         /*
178          * Extract package data.
179          */
180         for (i = 0; i < format_count; i++) {
181
182                 u8 **pointer = NULL;
183                 union acpi_object *element = &(package->package.elements[i]);
184
185                 if (!element) {
186                         return AE_BAD_DATA;
187                 }
188
189                 switch (element->type) {
190
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;
212                         }
213                         break;
214
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;
240                         }
241                         break;
242
243                 case ACPI_TYPE_PACKAGE:
244                         /* TBD: handle nested packages... */
245                 default:
246                         /* Should never get here */
247                         break;
248                 }
249         }
250
251         return AE_OK;
252 }
253
254 EXPORT_SYMBOL(acpi_extract_package);
255
256 acpi_status
257 acpi_evaluate_integer(acpi_handle handle,
258                       acpi_string pathname,
259                       struct acpi_object_list *arguments, unsigned long *data)
260 {
261         acpi_status status = AE_OK;
262         union acpi_object *element;
263         struct acpi_buffer buffer = { 0, NULL };
264
265
266         if (!data)
267                 return AE_BAD_PARAMETER;
268
269         element = kzalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
270         if (!element)
271                 return AE_NO_MEMORY;
272
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;
280         }
281
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;
286         }
287
288         *data = element->integer.value;
289         kfree(element);
290
291         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%lu]\n", *data));
292
293         return AE_OK;
294 }
295
296 EXPORT_SYMBOL(acpi_evaluate_integer);
297
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)
303 {
304         acpi_status status = AE_OK;
305         acpi_object *element = NULL;
306         acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
307
308
309         if (!data)
310                 return AE_BAD_PARAMETER;
311
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;
316         }
317
318         element = (acpi_object *) buffer.pointer;
319
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;
325         }
326
327         *data = kzalloc(element->string.length + 1, GFP_KERNEL);
328         if (!data) {
329                 printk(KERN_ERR PREFIX "Memory allocation\n");
330                 return -ENOMEM;
331         }
332
333         memcpy(*data, element->string.pointer, element->string.length);
334
335         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data));
336
337         kfree(buffer.pointer);
338
339         return AE_OK;
340 }
341 #endif
342
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)
348 {
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;
354
355
356         if (!list) {
357                 return AE_BAD_PARAMETER;
358         }
359
360         /* Evaluate object. */
361
362         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
363         if (ACPI_FAILURE(status))
364                 goto end;
365
366         package = buffer.pointer;
367
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;
374         }
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;
381         }
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;
388         }
389
390         if (package->package.count > ACPI_MAX_HANDLES) {
391                 return AE_NO_MEMORY;
392         }
393         list->count = package->package.count;
394
395         /* Extract package data. */
396
397         for (i = 0; i < list->count; i++) {
398
399                 element = &(package->package.elements[i]);
400
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;
408                 }
409
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;
415                 }
416                 /* Get the  acpi_handle. */
417
418                 list->handles[i] = element->reference.handle;
419                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
420                                   list->handles[i]));
421         }
422
423       end:
424         if (ACPI_FAILURE(status)) {
425                 list->count = 0;
426                 //kfree(list->handles);
427         }
428
429         kfree(buffer.pointer);
430
431         return status;
432 }
433
434 EXPORT_SYMBOL(acpi_evaluate_reference);