xref: /openbmc/linux/drivers/acpi/utils.c (revision 64c70b1c)
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 #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 
62 	if (!package || (package->type != ACPI_TYPE_PACKAGE)
63 	    || (package->package.count < 1)) {
64 		printk(KERN_WARNING PREFIX "Invalid package argument\n");
65 		return AE_BAD_PARAMETER;
66 	}
67 
68 	if (!format || !format->pointer || (format->length < 1)) {
69 		printk(KERN_WARNING PREFIX "Invalid format argument\n");
70 		return AE_BAD_PARAMETER;
71 	}
72 
73 	if (!buffer) {
74 		printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
75 		return AE_BAD_PARAMETER;
76 	}
77 
78 	format_count = (format->length / sizeof(char)) - 1;
79 	if (format_count > package->package.count) {
80 		printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
81 			      " than exist in package [%d].\n",
82 			      format_count, package->package.count);
83 		return AE_BAD_DATA;
84 	}
85 
86 	format_string = format->pointer;
87 
88 	/*
89 	 * Calculate size_required.
90 	 */
91 	for (i = 0; i < format_count; i++) {
92 
93 		union acpi_object *element = &(package->package.elements[i]);
94 
95 		if (!element) {
96 			return AE_BAD_DATA;
97 		}
98 
99 		switch (element->type) {
100 
101 		case ACPI_TYPE_INTEGER:
102 			switch (format_string[i]) {
103 			case 'N':
104 				size_required += sizeof(acpi_integer);
105 				tail_offset += sizeof(acpi_integer);
106 				break;
107 			case 'S':
108 				size_required +=
109 				    sizeof(char *) + sizeof(acpi_integer) +
110 				    sizeof(char);
111 				tail_offset += sizeof(char *);
112 				break;
113 			default:
114 				printk(KERN_WARNING PREFIX "Invalid package element"
115 					      " [%d]: got number, expecing"
116 					      " [%c]\n",
117 					      i, format_string[i]);
118 				return AE_BAD_DATA;
119 				break;
120 			}
121 			break;
122 
123 		case ACPI_TYPE_STRING:
124 		case ACPI_TYPE_BUFFER:
125 			switch (format_string[i]) {
126 			case 'S':
127 				size_required +=
128 				    sizeof(char *) +
129 				    (element->string.length * sizeof(char)) +
130 				    sizeof(char);
131 				tail_offset += sizeof(char *);
132 				break;
133 			case 'B':
134 				size_required +=
135 				    sizeof(u8 *) +
136 				    (element->buffer.length * sizeof(u8));
137 				tail_offset += sizeof(u8 *);
138 				break;
139 			default:
140 				printk(KERN_WARNING PREFIX "Invalid package element"
141 					      " [%d] got string/buffer,"
142 					      " expecing [%c]\n",
143 					      i, format_string[i]);
144 				return 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 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 AE_BUFFER_OVERFLOW;
166 	} else if (buffer->length != size_required || !buffer->pointer) {
167 		return 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 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 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 
262 	if (!data)
263 		return AE_BAD_PARAMETER;
264 
265 	element = kzalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
266 	if (!element)
267 		return AE_NO_MEMORY;
268 
269 	buffer.length = sizeof(union acpi_object);
270 	buffer.pointer = element;
271 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
272 	if (ACPI_FAILURE(status)) {
273 		acpi_util_eval_error(handle, pathname, status);
274 		kfree(element);
275 		return status;
276 	}
277 
278 	if (element->type != ACPI_TYPE_INTEGER) {
279 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
280 		kfree(element);
281 		return AE_BAD_DATA;
282 	}
283 
284 	*data = element->integer.value;
285 	kfree(element);
286 
287 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%lu]\n", *data));
288 
289 	return AE_OK;
290 }
291 
292 EXPORT_SYMBOL(acpi_evaluate_integer);
293 
294 #if 0
295 acpi_status
296 acpi_evaluate_string(acpi_handle handle,
297 		     acpi_string pathname,
298 		     acpi_object_list * arguments, acpi_string * data)
299 {
300 	acpi_status status = AE_OK;
301 	acpi_object *element = NULL;
302 	acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
303 
304 
305 	if (!data)
306 		return AE_BAD_PARAMETER;
307 
308 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
309 	if (ACPI_FAILURE(status)) {
310 		acpi_util_eval_error(handle, pathname, status);
311 		return status;
312 	}
313 
314 	element = (acpi_object *) buffer.pointer;
315 
316 	if ((element->type != ACPI_TYPE_STRING)
317 	    || (element->type != ACPI_TYPE_BUFFER)
318 	    || !element->string.length) {
319 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
320 		return AE_BAD_DATA;
321 	}
322 
323 	*data = kzalloc(element->string.length + 1, GFP_KERNEL);
324 	if (!data) {
325 		printk(KERN_ERR PREFIX "Memory allocation\n");
326 		return -ENOMEM;
327 	}
328 
329 	memcpy(*data, element->string.pointer, element->string.length);
330 
331 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data));
332 
333 	kfree(buffer.pointer);
334 
335 	return AE_OK;
336 }
337 #endif
338 
339 acpi_status
340 acpi_evaluate_reference(acpi_handle handle,
341 			acpi_string pathname,
342 			struct acpi_object_list *arguments,
343 			struct acpi_handle_list *list)
344 {
345 	acpi_status status = AE_OK;
346 	union acpi_object *package = NULL;
347 	union acpi_object *element = NULL;
348 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
349 	u32 i = 0;
350 
351 
352 	if (!list) {
353 		return AE_BAD_PARAMETER;
354 	}
355 
356 	/* Evaluate object. */
357 
358 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
359 	if (ACPI_FAILURE(status))
360 		goto end;
361 
362 	package = buffer.pointer;
363 
364 	if ((buffer.length == 0) || !package) {
365 		printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
366 			    (unsigned)buffer.length, package);
367 		status = AE_BAD_DATA;
368 		acpi_util_eval_error(handle, pathname, status);
369 		goto end;
370 	}
371 	if (package->type != ACPI_TYPE_PACKAGE) {
372 		printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
373 			    package->type);
374 		status = AE_BAD_DATA;
375 		acpi_util_eval_error(handle, pathname, status);
376 		goto end;
377 	}
378 	if (!package->package.count) {
379 		printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
380 			    package);
381 		status = AE_BAD_DATA;
382 		acpi_util_eval_error(handle, pathname, status);
383 		goto end;
384 	}
385 
386 	if (package->package.count > ACPI_MAX_HANDLES) {
387 		return AE_NO_MEMORY;
388 	}
389 	list->count = package->package.count;
390 
391 	/* Extract package data. */
392 
393 	for (i = 0; i < list->count; i++) {
394 
395 		element = &(package->package.elements[i]);
396 
397 		if (element->type != ACPI_TYPE_ANY) {
398 			status = AE_BAD_DATA;
399 			printk(KERN_ERR PREFIX
400 				    "Expecting a [Reference] package element, found type %X\n",
401 				    element->type);
402 			acpi_util_eval_error(handle, pathname, status);
403 			break;
404 		}
405 
406 		/* Get the  acpi_handle. */
407 
408 		list->handles[i] = element->reference.handle;
409 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
410 				  list->handles[i]));
411 	}
412 
413       end:
414 	if (ACPI_FAILURE(status)) {
415 		list->count = 0;
416 		//kfree(list->handles);
417 	}
418 
419 	kfree(buffer.pointer);
420 
421 	return status;
422 }
423 
424 EXPORT_SYMBOL(acpi_evaluate_reference);
425