xref: /openbmc/linux/drivers/acpi/utils.c (revision b6bec26c)
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/slab.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/hardirq.h>
32 #include <linux/acpi.h>
33 #include <acpi/acpi_bus.h>
34 #include <acpi/acpi_drivers.h>
35 
36 #include "internal.h"
37 
38 #define _COMPONENT		ACPI_BUS_COMPONENT
39 ACPI_MODULE_NAME("utils");
40 
41 /* --------------------------------------------------------------------------
42                             Object Evaluation Helpers
43    -------------------------------------------------------------------------- */
44 static void
45 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
46 {
47 #ifdef ACPI_DEBUG_OUTPUT
48 	char prefix[80] = {'\0'};
49 	struct acpi_buffer buffer = {sizeof(prefix), prefix};
50 	acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
51 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
52 		(char *) prefix, p, acpi_format_exception(s)));
53 #else
54 	return;
55 #endif
56 }
57 
58 acpi_status
59 acpi_extract_package(union acpi_object *package,
60 		     struct acpi_buffer *format, struct acpi_buffer *buffer)
61 {
62 	u32 size_required = 0;
63 	u32 tail_offset = 0;
64 	char *format_string = NULL;
65 	u32 format_count = 0;
66 	u32 i = 0;
67 	u8 *head = NULL;
68 	u8 *tail = NULL;
69 
70 
71 	if (!package || (package->type != ACPI_TYPE_PACKAGE)
72 	    || (package->package.count < 1)) {
73 		printk(KERN_WARNING PREFIX "Invalid package argument\n");
74 		return AE_BAD_PARAMETER;
75 	}
76 
77 	if (!format || !format->pointer || (format->length < 1)) {
78 		printk(KERN_WARNING PREFIX "Invalid format argument\n");
79 		return AE_BAD_PARAMETER;
80 	}
81 
82 	if (!buffer) {
83 		printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
84 		return AE_BAD_PARAMETER;
85 	}
86 
87 	format_count = (format->length / sizeof(char)) - 1;
88 	if (format_count > package->package.count) {
89 		printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
90 			      " than exist in package [%d].\n",
91 			      format_count, package->package.count);
92 		return AE_BAD_DATA;
93 	}
94 
95 	format_string = format->pointer;
96 
97 	/*
98 	 * Calculate size_required.
99 	 */
100 	for (i = 0; i < format_count; i++) {
101 
102 		union acpi_object *element = &(package->package.elements[i]);
103 
104 		if (!element) {
105 			return AE_BAD_DATA;
106 		}
107 
108 		switch (element->type) {
109 
110 		case ACPI_TYPE_INTEGER:
111 			switch (format_string[i]) {
112 			case 'N':
113 				size_required += sizeof(u64);
114 				tail_offset += sizeof(u64);
115 				break;
116 			case 'S':
117 				size_required +=
118 				    sizeof(char *) + sizeof(u64) +
119 				    sizeof(char);
120 				tail_offset += sizeof(char *);
121 				break;
122 			default:
123 				printk(KERN_WARNING PREFIX "Invalid package element"
124 					      " [%d]: got number, expecing"
125 					      " [%c]\n",
126 					      i, format_string[i]);
127 				return AE_BAD_DATA;
128 				break;
129 			}
130 			break;
131 
132 		case ACPI_TYPE_STRING:
133 		case ACPI_TYPE_BUFFER:
134 			switch (format_string[i]) {
135 			case 'S':
136 				size_required +=
137 				    sizeof(char *) +
138 				    (element->string.length * sizeof(char)) +
139 				    sizeof(char);
140 				tail_offset += sizeof(char *);
141 				break;
142 			case 'B':
143 				size_required +=
144 				    sizeof(u8 *) +
145 				    (element->buffer.length * sizeof(u8));
146 				tail_offset += sizeof(u8 *);
147 				break;
148 			default:
149 				printk(KERN_WARNING PREFIX "Invalid package element"
150 					      " [%d] got string/buffer,"
151 					      " expecing [%c]\n",
152 					      i, format_string[i]);
153 				return AE_BAD_DATA;
154 				break;
155 			}
156 			break;
157 
158 		case ACPI_TYPE_PACKAGE:
159 		default:
160 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
161 					  "Found unsupported element at index=%d\n",
162 					  i));
163 			/* TBD: handle nested packages... */
164 			return AE_SUPPORT;
165 			break;
166 		}
167 	}
168 
169 	/*
170 	 * Validate output buffer.
171 	 */
172 	if (buffer->length < size_required) {
173 		buffer->length = size_required;
174 		return AE_BUFFER_OVERFLOW;
175 	} else if (buffer->length != size_required || !buffer->pointer) {
176 		return AE_BAD_PARAMETER;
177 	}
178 
179 	head = buffer->pointer;
180 	tail = buffer->pointer + tail_offset;
181 
182 	/*
183 	 * Extract package data.
184 	 */
185 	for (i = 0; i < format_count; i++) {
186 
187 		u8 **pointer = NULL;
188 		union acpi_object *element = &(package->package.elements[i]);
189 
190 		if (!element) {
191 			return AE_BAD_DATA;
192 		}
193 
194 		switch (element->type) {
195 
196 		case ACPI_TYPE_INTEGER:
197 			switch (format_string[i]) {
198 			case 'N':
199 				*((u64 *) head) =
200 				    element->integer.value;
201 				head += sizeof(u64);
202 				break;
203 			case 'S':
204 				pointer = (u8 **) head;
205 				*pointer = tail;
206 				*((u64 *) tail) =
207 				    element->integer.value;
208 				head += sizeof(u64 *);
209 				tail += sizeof(u64);
210 				/* NULL terminate string */
211 				*tail = (char)0;
212 				tail += sizeof(char);
213 				break;
214 			default:
215 				/* Should never get here */
216 				break;
217 			}
218 			break;
219 
220 		case ACPI_TYPE_STRING:
221 		case ACPI_TYPE_BUFFER:
222 			switch (format_string[i]) {
223 			case 'S':
224 				pointer = (u8 **) head;
225 				*pointer = tail;
226 				memcpy(tail, element->string.pointer,
227 				       element->string.length);
228 				head += sizeof(char *);
229 				tail += element->string.length * sizeof(char);
230 				/* NULL terminate string */
231 				*tail = (char)0;
232 				tail += sizeof(char);
233 				break;
234 			case 'B':
235 				pointer = (u8 **) head;
236 				*pointer = tail;
237 				memcpy(tail, element->buffer.pointer,
238 				       element->buffer.length);
239 				head += sizeof(u8 *);
240 				tail += element->buffer.length * sizeof(u8);
241 				break;
242 			default:
243 				/* Should never get here */
244 				break;
245 			}
246 			break;
247 
248 		case ACPI_TYPE_PACKAGE:
249 			/* TBD: handle nested packages... */
250 		default:
251 			/* Should never get here */
252 			break;
253 		}
254 	}
255 
256 	return AE_OK;
257 }
258 
259 EXPORT_SYMBOL(acpi_extract_package);
260 
261 acpi_status
262 acpi_evaluate_integer(acpi_handle handle,
263 		      acpi_string pathname,
264 		      struct acpi_object_list *arguments, unsigned long long *data)
265 {
266 	acpi_status status = AE_OK;
267 	union acpi_object element;
268 	struct acpi_buffer buffer = { 0, NULL };
269 
270 	if (!data)
271 		return AE_BAD_PARAMETER;
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 		return status;
279 	}
280 
281 	if (element.type != ACPI_TYPE_INTEGER) {
282 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
283 		return AE_BAD_DATA;
284 	}
285 
286 	*data = element.integer.value;
287 
288 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
289 
290 	return AE_OK;
291 }
292 
293 EXPORT_SYMBOL(acpi_evaluate_integer);
294 
295 acpi_status
296 acpi_evaluate_reference(acpi_handle handle,
297 			acpi_string pathname,
298 			struct acpi_object_list *arguments,
299 			struct acpi_handle_list *list)
300 {
301 	acpi_status status = AE_OK;
302 	union acpi_object *package = NULL;
303 	union acpi_object *element = NULL;
304 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
305 	u32 i = 0;
306 
307 
308 	if (!list) {
309 		return AE_BAD_PARAMETER;
310 	}
311 
312 	/* Evaluate object. */
313 
314 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
315 	if (ACPI_FAILURE(status))
316 		goto end;
317 
318 	package = buffer.pointer;
319 
320 	if ((buffer.length == 0) || !package) {
321 		printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
322 			    (unsigned)buffer.length, package);
323 		status = AE_BAD_DATA;
324 		acpi_util_eval_error(handle, pathname, status);
325 		goto end;
326 	}
327 	if (package->type != ACPI_TYPE_PACKAGE) {
328 		printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
329 			    package->type);
330 		status = AE_BAD_DATA;
331 		acpi_util_eval_error(handle, pathname, status);
332 		goto end;
333 	}
334 	if (!package->package.count) {
335 		printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
336 			    package);
337 		status = AE_BAD_DATA;
338 		acpi_util_eval_error(handle, pathname, status);
339 		goto end;
340 	}
341 
342 	if (package->package.count > ACPI_MAX_HANDLES) {
343 		return AE_NO_MEMORY;
344 	}
345 	list->count = package->package.count;
346 
347 	/* Extract package data. */
348 
349 	for (i = 0; i < list->count; i++) {
350 
351 		element = &(package->package.elements[i]);
352 
353 		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
354 			status = AE_BAD_DATA;
355 			printk(KERN_ERR PREFIX
356 				    "Expecting a [Reference] package element, found type %X\n",
357 				    element->type);
358 			acpi_util_eval_error(handle, pathname, status);
359 			break;
360 		}
361 
362 		if (!element->reference.handle) {
363 			printk(KERN_WARNING PREFIX "Invalid reference in"
364 			       " package %s\n", pathname);
365 			status = AE_NULL_ENTRY;
366 			break;
367 		}
368 		/* Get the  acpi_handle. */
369 
370 		list->handles[i] = element->reference.handle;
371 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
372 				  list->handles[i]));
373 	}
374 
375       end:
376 	if (ACPI_FAILURE(status)) {
377 		list->count = 0;
378 		//kfree(list->handles);
379 	}
380 
381 	kfree(buffer.pointer);
382 
383 	return status;
384 }
385 
386 EXPORT_SYMBOL(acpi_evaluate_reference);
387 
388 acpi_status
389 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
390 {
391 	acpi_status status;
392 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
393 	union acpi_object *output;
394 
395 	status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
396 
397 	if (ACPI_FAILURE(status))
398 		return status;
399 
400 	output = buffer.pointer;
401 
402 	if (!output || output->type != ACPI_TYPE_PACKAGE
403 	    || !output->package.count
404 	    || output->package.elements[0].type != ACPI_TYPE_BUFFER
405 	    || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
406 		status = AE_TYPE;
407 		goto out;
408 	}
409 
410 	status = acpi_decode_pld_buffer(
411 			output->package.elements[0].buffer.pointer,
412 			output->package.elements[0].buffer.length,
413 			pld);
414 
415 out:
416 	kfree(buffer.pointer);
417 	return status;
418 }
419 EXPORT_SYMBOL(acpi_get_physical_device_location);
420 
421 /**
422  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
423  * @handle: ACPI device handle
424  * @source_event: source event code
425  * @status_code: status code
426  * @status_buf: optional detailed information (NULL if none)
427  *
428  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
429  * must call this function when evaluating _OST for hotplug operations.
430  * When the platform does not support _OST, this function has no effect.
431  */
432 acpi_status
433 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
434 		u32 status_code, struct acpi_buffer *status_buf)
435 {
436 #ifdef ACPI_HOTPLUG_OST
437 	union acpi_object params[3] = {
438 		{.type = ACPI_TYPE_INTEGER,},
439 		{.type = ACPI_TYPE_INTEGER,},
440 		{.type = ACPI_TYPE_BUFFER,}
441 	};
442 	struct acpi_object_list arg_list = {3, params};
443 	acpi_status status;
444 
445 	params[0].integer.value = source_event;
446 	params[1].integer.value = status_code;
447 	if (status_buf != NULL) {
448 		params[2].buffer.pointer = status_buf->pointer;
449 		params[2].buffer.length = status_buf->length;
450 	} else {
451 		params[2].buffer.pointer = NULL;
452 		params[2].buffer.length = 0;
453 	}
454 
455 	status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
456 	return status;
457 #else
458 	return AE_OK;
459 #endif
460 }
461 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
462 
463 /**
464  * acpi_handle_printk: Print message with ACPI prefix and object path
465  *
466  * This function is called through acpi_handle_<level> macros and prints
467  * a message with ACPI prefix and object path.  This function acquires
468  * the global namespace mutex to obtain an object path.  In interrupt
469  * context, it shows the object path as <n/a>.
470  */
471 void
472 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
473 {
474 	struct va_format vaf;
475 	va_list args;
476 	struct acpi_buffer buffer = {
477 		.length = ACPI_ALLOCATE_BUFFER,
478 		.pointer = NULL
479 	};
480 	const char *path;
481 
482 	va_start(args, fmt);
483 	vaf.fmt = fmt;
484 	vaf.va = &args;
485 
486 	if (in_interrupt() ||
487 	    acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
488 		path = "<n/a>";
489 	else
490 		path = buffer.pointer;
491 
492 	printk("%sACPI: %s: %pV", level, path, &vaf);
493 
494 	va_end(args);
495 	kfree(buffer.pointer);
496 }
497 EXPORT_SYMBOL(acpi_handle_printk);
498