xref: /openbmc/linux/drivers/acpi/utils.c (revision 545e4006)
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_LOCAL_REFERENCE) {
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);
435