xref: /linux/drivers/acpi/utils.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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("acpi_utils")
35 
36 /* --------------------------------------------------------------------------
37                             Object Evaluation Helpers
38    -------------------------------------------------------------------------- */
39 #ifdef ACPI_DEBUG_OUTPUT
40 #define acpi_util_eval_error(h,p,s) {\
41 	char prefix[80] = {'\0'};\
42 	struct acpi_buffer buffer = {sizeof(prefix), prefix};\
43 	acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);\
44 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",\
45 		(char *) prefix, p, acpi_format_exception(s))); }
46 #else
47 #define acpi_util_eval_error(h,p,s)
48 #endif
49 acpi_status
50 acpi_extract_package(union acpi_object *package,
51 		     struct acpi_buffer *format, struct acpi_buffer *buffer)
52 {
53 	u32 size_required = 0;
54 	u32 tail_offset = 0;
55 	char *format_string = NULL;
56 	u32 format_count = 0;
57 	u32 i = 0;
58 	u8 *head = NULL;
59 	u8 *tail = NULL;
60 
61 	ACPI_FUNCTION_TRACE("acpi_extract_package");
62 
63 	if (!package || (package->type != ACPI_TYPE_PACKAGE)
64 	    || (package->package.count < 1)) {
65 		ACPI_DEBUG_PRINT((ACPI_DB_WARN,
66 				  "Invalid 'package' argument\n"));
67 		return_ACPI_STATUS(AE_BAD_PARAMETER);
68 	}
69 
70 	if (!format || !format->pointer || (format->length < 1)) {
71 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid 'format' argument\n"));
72 		return_ACPI_STATUS(AE_BAD_PARAMETER);
73 	}
74 
75 	if (!buffer) {
76 		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid 'buffer' argument\n"));
77 		return_ACPI_STATUS(AE_BAD_PARAMETER);
78 	}
79 
80 	format_count = (format->length / sizeof(char)) - 1;
81 	if (format_count > package->package.count) {
82 		ACPI_DEBUG_PRINT((ACPI_DB_WARN,
83 				  "Format specifies more objects [%d] than exist in package [%d].",
84 				  format_count, package->package.count));
85 		return_ACPI_STATUS(AE_BAD_DATA);
86 	}
87 
88 	format_string = (char *)format->pointer;
89 
90 	/*
91 	 * Calculate size_required.
92 	 */
93 	for (i = 0; i < format_count; i++) {
94 
95 		union acpi_object *element = &(package->package.elements[i]);
96 
97 		if (!element) {
98 			return_ACPI_STATUS(AE_BAD_DATA);
99 		}
100 
101 		switch (element->type) {
102 
103 		case ACPI_TYPE_INTEGER:
104 			switch (format_string[i]) {
105 			case 'N':
106 				size_required += sizeof(acpi_integer);
107 				tail_offset += sizeof(acpi_integer);
108 				break;
109 			case 'S':
110 				size_required +=
111 				    sizeof(char *) + sizeof(acpi_integer) +
112 				    sizeof(char);
113 				tail_offset += sizeof(char *);
114 				break;
115 			default:
116 				ACPI_DEBUG_PRINT((ACPI_DB_WARN,
117 						  "Invalid package element [%d]: got number, expecing [%c].\n",
118 						  i, format_string[i]));
119 				return_ACPI_STATUS(AE_BAD_DATA);
120 				break;
121 			}
122 			break;
123 
124 		case ACPI_TYPE_STRING:
125 		case ACPI_TYPE_BUFFER:
126 			switch (format_string[i]) {
127 			case 'S':
128 				size_required +=
129 				    sizeof(char *) +
130 				    (element->string.length * sizeof(char)) +
131 				    sizeof(char);
132 				tail_offset += sizeof(char *);
133 				break;
134 			case 'B':
135 				size_required +=
136 				    sizeof(u8 *) +
137 				    (element->buffer.length * sizeof(u8));
138 				tail_offset += sizeof(u8 *);
139 				break;
140 			default:
141 				ACPI_DEBUG_PRINT((ACPI_DB_WARN,
142 						  "Invalid package element [%d] got string/buffer, expecing [%c].\n",
143 						  i, format_string[i]));
144 				return_ACPI_STATUS(AE_BAD_DATA);
145 				break;
146 			}
147 			break;
148 
149 		case ACPI_TYPE_PACKAGE:
150 		default:
151 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
152 					  "Found unsupported element at index=%d\n",
153 					  i));
154 			/* TBD: handle nested packages... */
155 			return_ACPI_STATUS(AE_SUPPORT);
156 			break;
157 		}
158 	}
159 
160 	/*
161 	 * Validate output buffer.
162 	 */
163 	if (buffer->length < size_required) {
164 		buffer->length = size_required;
165 		return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
166 	} else if (buffer->length != size_required || !buffer->pointer) {
167 		return_ACPI_STATUS(AE_BAD_PARAMETER);
168 	}
169 
170 	head = buffer->pointer;
171 	tail = buffer->pointer + tail_offset;
172 
173 	/*
174 	 * Extract package data.
175 	 */
176 	for (i = 0; i < format_count; i++) {
177 
178 		u8 **pointer = NULL;
179 		union acpi_object *element = &(package->package.elements[i]);
180 
181 		if (!element) {
182 			return_ACPI_STATUS(AE_BAD_DATA);
183 		}
184 
185 		switch (element->type) {
186 
187 		case ACPI_TYPE_INTEGER:
188 			switch (format_string[i]) {
189 			case 'N':
190 				*((acpi_integer *) head) =
191 				    element->integer.value;
192 				head += sizeof(acpi_integer);
193 				break;
194 			case 'S':
195 				pointer = (u8 **) head;
196 				*pointer = tail;
197 				*((acpi_integer *) tail) =
198 				    element->integer.value;
199 				head += sizeof(acpi_integer *);
200 				tail += sizeof(acpi_integer);
201 				/* NULL terminate string */
202 				*tail = (char)0;
203 				tail += sizeof(char);
204 				break;
205 			default:
206 				/* Should never get here */
207 				break;
208 			}
209 			break;
210 
211 		case ACPI_TYPE_STRING:
212 		case ACPI_TYPE_BUFFER:
213 			switch (format_string[i]) {
214 			case 'S':
215 				pointer = (u8 **) head;
216 				*pointer = tail;
217 				memcpy(tail, element->string.pointer,
218 				       element->string.length);
219 				head += sizeof(char *);
220 				tail += element->string.length * sizeof(char);
221 				/* NULL terminate string */
222 				*tail = (char)0;
223 				tail += sizeof(char);
224 				break;
225 			case 'B':
226 				pointer = (u8 **) head;
227 				*pointer = tail;
228 				memcpy(tail, element->buffer.pointer,
229 				       element->buffer.length);
230 				head += sizeof(u8 *);
231 				tail += element->buffer.length * sizeof(u8);
232 				break;
233 			default:
234 				/* Should never get here */
235 				break;
236 			}
237 			break;
238 
239 		case ACPI_TYPE_PACKAGE:
240 			/* TBD: handle nested packages... */
241 		default:
242 			/* Should never get here */
243 			break;
244 		}
245 	}
246 
247 	return_ACPI_STATUS(AE_OK);
248 }
249 
250 EXPORT_SYMBOL(acpi_extract_package);
251 
252 acpi_status
253 acpi_evaluate_integer(acpi_handle handle,
254 		      acpi_string pathname,
255 		      struct acpi_object_list *arguments, unsigned long *data)
256 {
257 	acpi_status status = AE_OK;
258 	union acpi_object *element;
259 	struct acpi_buffer buffer = { 0, NULL };
260 
261 	ACPI_FUNCTION_TRACE("acpi_evaluate_integer");
262 
263 	if (!data)
264 		return_ACPI_STATUS(AE_BAD_PARAMETER);
265 
266 	element = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
267 	if (!element)
268 		return_ACPI_STATUS(AE_NO_MEMORY);
269 
270 	memset(element, 0, sizeof(union acpi_object));
271 	buffer.length = sizeof(union acpi_object);
272 	buffer.pointer = element;
273 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
274 	if (ACPI_FAILURE(status)) {
275 		acpi_util_eval_error(handle, pathname, status);
276 		kfree(element);
277 		return_ACPI_STATUS(status);
278 	}
279 
280 	if (element->type != ACPI_TYPE_INTEGER) {
281 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
282 		kfree(element);
283 		return_ACPI_STATUS(AE_BAD_DATA);
284 	}
285 
286 	*data = element->integer.value;
287 	kfree(element);
288 
289 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%lu]\n", *data));
290 
291 	return_ACPI_STATUS(AE_OK);
292 }
293 
294 EXPORT_SYMBOL(acpi_evaluate_integer);
295 
296 #if 0
297 acpi_status
298 acpi_evaluate_string(acpi_handle handle,
299 		     acpi_string pathname,
300 		     acpi_object_list * arguments, acpi_string * data)
301 {
302 	acpi_status status = AE_OK;
303 	acpi_object *element = NULL;
304 	acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
305 
306 	ACPI_FUNCTION_TRACE("acpi_evaluate_string");
307 
308 	if (!data)
309 		return_ACPI_STATUS(AE_BAD_PARAMETER);
310 
311 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
312 	if (ACPI_FAILURE(status)) {
313 		acpi_util_eval_error(handle, pathname, status);
314 		return_ACPI_STATUS(status);
315 	}
316 
317 	element = (acpi_object *) buffer.pointer;
318 
319 	if ((element->type != ACPI_TYPE_STRING)
320 	    || (element->type != ACPI_TYPE_BUFFER)
321 	    || !element->string.length) {
322 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
323 		return_ACPI_STATUS(AE_BAD_DATA);
324 	}
325 
326 	*data = kmalloc(element->string.length + 1, GFP_KERNEL);
327 	if (!data) {
328 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Memory allocation error\n"));
329 		return_VALUE(-ENOMEM);
330 	}
331 	memset(*data, 0, element->string.length + 1);
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 	acpi_os_free(buffer.pointer);
338 
339 	return_ACPI_STATUS(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 	ACPI_FUNCTION_TRACE("acpi_evaluate_reference");
356 
357 	if (!list) {
358 		return_ACPI_STATUS(AE_BAD_PARAMETER);
359 	}
360 
361 	/* Evaluate object. */
362 
363 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
364 	if (ACPI_FAILURE(status))
365 		goto end;
366 
367 	package = (union acpi_object *)buffer.pointer;
368 
369 	if ((buffer.length == 0) || !package) {
370 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
371 				  "No return object (len %X ptr %p)\n",
372 				  (unsigned)buffer.length, package));
373 		status = AE_BAD_DATA;
374 		acpi_util_eval_error(handle, pathname, status);
375 		goto end;
376 	}
377 	if (package->type != ACPI_TYPE_PACKAGE) {
378 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
379 				  "Expecting a [Package], found type %X\n",
380 				  package->type));
381 		status = AE_BAD_DATA;
382 		acpi_util_eval_error(handle, pathname, status);
383 		goto end;
384 	}
385 	if (!package->package.count) {
386 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
387 				  "[Package] has zero elements (%p)\n",
388 				  package));
389 		status = AE_BAD_DATA;
390 		acpi_util_eval_error(handle, pathname, status);
391 		goto end;
392 	}
393 
394 	if (package->package.count > ACPI_MAX_HANDLES) {
395 		return_ACPI_STATUS(AE_NO_MEMORY);
396 	}
397 	list->count = package->package.count;
398 
399 	/* Extract package data. */
400 
401 	for (i = 0; i < list->count; i++) {
402 
403 		element = &(package->package.elements[i]);
404 
405 		if (element->type != ACPI_TYPE_ANY) {
406 			status = AE_BAD_DATA;
407 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
408 					  "Expecting a [Reference] package element, found type %X\n",
409 					  element->type));
410 			acpi_util_eval_error(handle, pathname, status);
411 			break;
412 		}
413 
414 		/* Get the  acpi_handle. */
415 
416 		list->handles[i] = element->reference.handle;
417 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
418 				  list->handles[i]));
419 	}
420 
421       end:
422 	if (ACPI_FAILURE(status)) {
423 		list->count = 0;
424 		//kfree(list->handles);
425 	}
426 
427 	acpi_os_free(buffer.pointer);
428 
429 	return_ACPI_STATUS(status);
430 }
431 
432 EXPORT_SYMBOL(acpi_evaluate_reference);
433