xref: /openbmc/linux/drivers/acpi/utils.c (revision 930beb5a)
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, expecting"
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 					      " expecting [%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 == ACPI_ALLOCATE_BUFFER) {
173 		buffer->pointer = ACPI_ALLOCATE(size_required);
174 		if (!buffer->pointer)
175 			return AE_NO_MEMORY;
176 		buffer->length = size_required;
177 		memset(buffer->pointer, 0, size_required);
178 	} else {
179 		if (buffer->length < size_required) {
180 			buffer->length = size_required;
181 			return AE_BUFFER_OVERFLOW;
182 		} else if (buffer->length != size_required ||
183 			   !buffer->pointer) {
184 			return AE_BAD_PARAMETER;
185 		}
186 	}
187 
188 	head = buffer->pointer;
189 	tail = buffer->pointer + tail_offset;
190 
191 	/*
192 	 * Extract package data.
193 	 */
194 	for (i = 0; i < format_count; i++) {
195 
196 		u8 **pointer = NULL;
197 		union acpi_object *element = &(package->package.elements[i]);
198 
199 		if (!element) {
200 			return AE_BAD_DATA;
201 		}
202 
203 		switch (element->type) {
204 
205 		case ACPI_TYPE_INTEGER:
206 			switch (format_string[i]) {
207 			case 'N':
208 				*((u64 *) head) =
209 				    element->integer.value;
210 				head += sizeof(u64);
211 				break;
212 			case 'S':
213 				pointer = (u8 **) head;
214 				*pointer = tail;
215 				*((u64 *) tail) =
216 				    element->integer.value;
217 				head += sizeof(u64 *);
218 				tail += sizeof(u64);
219 				/* NULL terminate string */
220 				*tail = (char)0;
221 				tail += sizeof(char);
222 				break;
223 			default:
224 				/* Should never get here */
225 				break;
226 			}
227 			break;
228 
229 		case ACPI_TYPE_STRING:
230 		case ACPI_TYPE_BUFFER:
231 			switch (format_string[i]) {
232 			case 'S':
233 				pointer = (u8 **) head;
234 				*pointer = tail;
235 				memcpy(tail, element->string.pointer,
236 				       element->string.length);
237 				head += sizeof(char *);
238 				tail += element->string.length * sizeof(char);
239 				/* NULL terminate string */
240 				*tail = (char)0;
241 				tail += sizeof(char);
242 				break;
243 			case 'B':
244 				pointer = (u8 **) head;
245 				*pointer = tail;
246 				memcpy(tail, element->buffer.pointer,
247 				       element->buffer.length);
248 				head += sizeof(u8 *);
249 				tail += element->buffer.length * sizeof(u8);
250 				break;
251 			default:
252 				/* Should never get here */
253 				break;
254 			}
255 			break;
256 
257 		case ACPI_TYPE_PACKAGE:
258 			/* TBD: handle nested packages... */
259 		default:
260 			/* Should never get here */
261 			break;
262 		}
263 	}
264 
265 	return AE_OK;
266 }
267 
268 EXPORT_SYMBOL(acpi_extract_package);
269 
270 acpi_status
271 acpi_evaluate_integer(acpi_handle handle,
272 		      acpi_string pathname,
273 		      struct acpi_object_list *arguments, unsigned long long *data)
274 {
275 	acpi_status status = AE_OK;
276 	union acpi_object element;
277 	struct acpi_buffer buffer = { 0, NULL };
278 
279 	if (!data)
280 		return AE_BAD_PARAMETER;
281 
282 	buffer.length = sizeof(union acpi_object);
283 	buffer.pointer = &element;
284 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
285 	if (ACPI_FAILURE(status)) {
286 		acpi_util_eval_error(handle, pathname, status);
287 		return status;
288 	}
289 
290 	if (element.type != ACPI_TYPE_INTEGER) {
291 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
292 		return AE_BAD_DATA;
293 	}
294 
295 	*data = element.integer.value;
296 
297 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
298 
299 	return AE_OK;
300 }
301 
302 EXPORT_SYMBOL(acpi_evaluate_integer);
303 
304 acpi_status
305 acpi_evaluate_reference(acpi_handle handle,
306 			acpi_string pathname,
307 			struct acpi_object_list *arguments,
308 			struct acpi_handle_list *list)
309 {
310 	acpi_status status = AE_OK;
311 	union acpi_object *package = NULL;
312 	union acpi_object *element = NULL;
313 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
314 	u32 i = 0;
315 
316 
317 	if (!list) {
318 		return AE_BAD_PARAMETER;
319 	}
320 
321 	/* Evaluate object. */
322 
323 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
324 	if (ACPI_FAILURE(status))
325 		goto end;
326 
327 	package = buffer.pointer;
328 
329 	if ((buffer.length == 0) || !package) {
330 		printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
331 			    (unsigned)buffer.length, package);
332 		status = AE_BAD_DATA;
333 		acpi_util_eval_error(handle, pathname, status);
334 		goto end;
335 	}
336 	if (package->type != ACPI_TYPE_PACKAGE) {
337 		printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
338 			    package->type);
339 		status = AE_BAD_DATA;
340 		acpi_util_eval_error(handle, pathname, status);
341 		goto end;
342 	}
343 	if (!package->package.count) {
344 		printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
345 			    package);
346 		status = AE_BAD_DATA;
347 		acpi_util_eval_error(handle, pathname, status);
348 		goto end;
349 	}
350 
351 	if (package->package.count > ACPI_MAX_HANDLES) {
352 		return AE_NO_MEMORY;
353 	}
354 	list->count = package->package.count;
355 
356 	/* Extract package data. */
357 
358 	for (i = 0; i < list->count; i++) {
359 
360 		element = &(package->package.elements[i]);
361 
362 		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
363 			status = AE_BAD_DATA;
364 			printk(KERN_ERR PREFIX
365 				    "Expecting a [Reference] package element, found type %X\n",
366 				    element->type);
367 			acpi_util_eval_error(handle, pathname, status);
368 			break;
369 		}
370 
371 		if (!element->reference.handle) {
372 			printk(KERN_WARNING PREFIX "Invalid reference in"
373 			       " package %s\n", pathname);
374 			status = AE_NULL_ENTRY;
375 			break;
376 		}
377 		/* Get the  acpi_handle. */
378 
379 		list->handles[i] = element->reference.handle;
380 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
381 				  list->handles[i]));
382 	}
383 
384       end:
385 	if (ACPI_FAILURE(status)) {
386 		list->count = 0;
387 		//kfree(list->handles);
388 	}
389 
390 	kfree(buffer.pointer);
391 
392 	return status;
393 }
394 
395 EXPORT_SYMBOL(acpi_evaluate_reference);
396 
397 acpi_status
398 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
399 {
400 	acpi_status status;
401 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
402 	union acpi_object *output;
403 
404 	status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
405 
406 	if (ACPI_FAILURE(status))
407 		return status;
408 
409 	output = buffer.pointer;
410 
411 	if (!output || output->type != ACPI_TYPE_PACKAGE
412 	    || !output->package.count
413 	    || output->package.elements[0].type != ACPI_TYPE_BUFFER
414 	    || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
415 		status = AE_TYPE;
416 		goto out;
417 	}
418 
419 	status = acpi_decode_pld_buffer(
420 			output->package.elements[0].buffer.pointer,
421 			output->package.elements[0].buffer.length,
422 			pld);
423 
424 out:
425 	kfree(buffer.pointer);
426 	return status;
427 }
428 EXPORT_SYMBOL(acpi_get_physical_device_location);
429 
430 /**
431  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
432  * @handle: ACPI device handle
433  * @source_event: source event code
434  * @status_code: status code
435  * @status_buf: optional detailed information (NULL if none)
436  *
437  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
438  * must call this function when evaluating _OST for hotplug operations.
439  * When the platform does not support _OST, this function has no effect.
440  */
441 acpi_status
442 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
443 		u32 status_code, struct acpi_buffer *status_buf)
444 {
445 #ifdef ACPI_HOTPLUG_OST
446 	union acpi_object params[3] = {
447 		{.type = ACPI_TYPE_INTEGER,},
448 		{.type = ACPI_TYPE_INTEGER,},
449 		{.type = ACPI_TYPE_BUFFER,}
450 	};
451 	struct acpi_object_list arg_list = {3, params};
452 	acpi_status status;
453 
454 	params[0].integer.value = source_event;
455 	params[1].integer.value = status_code;
456 	if (status_buf != NULL) {
457 		params[2].buffer.pointer = status_buf->pointer;
458 		params[2].buffer.length = status_buf->length;
459 	} else {
460 		params[2].buffer.pointer = NULL;
461 		params[2].buffer.length = 0;
462 	}
463 
464 	status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
465 	return status;
466 #else
467 	return AE_OK;
468 #endif
469 }
470 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
471 
472 /**
473  * acpi_handle_printk: Print message with ACPI prefix and object path
474  *
475  * This function is called through acpi_handle_<level> macros and prints
476  * a message with ACPI prefix and object path.  This function acquires
477  * the global namespace mutex to obtain an object path.  In interrupt
478  * context, it shows the object path as <n/a>.
479  */
480 void
481 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
482 {
483 	struct va_format vaf;
484 	va_list args;
485 	struct acpi_buffer buffer = {
486 		.length = ACPI_ALLOCATE_BUFFER,
487 		.pointer = NULL
488 	};
489 	const char *path;
490 
491 	va_start(args, fmt);
492 	vaf.fmt = fmt;
493 	vaf.va = &args;
494 
495 	if (in_interrupt() ||
496 	    acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
497 		path = "<n/a>";
498 	else
499 		path = buffer.pointer;
500 
501 	printk("%sACPI: %s: %pV", level, path, &vaf);
502 
503 	va_end(args);
504 	kfree(buffer.pointer);
505 }
506 EXPORT_SYMBOL(acpi_handle_printk);
507 
508 /**
509  * acpi_has_method: Check whether @handle has a method named @name
510  * @handle: ACPI device handle
511  * @name: name of object or method
512  *
513  * Check whether @handle has a method named @name.
514  */
515 bool acpi_has_method(acpi_handle handle, char *name)
516 {
517 	acpi_handle tmp;
518 
519 	return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
520 }
521 EXPORT_SYMBOL(acpi_has_method);
522 
523 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
524 				       u64 arg)
525 {
526 	union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
527 	struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
528 
529 	obj.integer.value = arg;
530 
531 	return acpi_evaluate_object(handle, method, &arg_list, NULL);
532 }
533 EXPORT_SYMBOL(acpi_execute_simple_method);
534 
535 /**
536  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
537  * @handle: ACPI device handle
538  *
539  * Evaluate device's _EJ0 method for hotplug operations.
540  */
541 acpi_status acpi_evaluate_ej0(acpi_handle handle)
542 {
543 	acpi_status status;
544 
545 	status = acpi_execute_simple_method(handle, "_EJ0", 1);
546 	if (status == AE_NOT_FOUND)
547 		acpi_handle_warn(handle, "No _EJ0 support for device\n");
548 	else if (ACPI_FAILURE(status))
549 		acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
550 
551 	return status;
552 }
553 
554 /**
555  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
556  * @handle: ACPI device handle
557  * @lock: lock device if non-zero, otherwise unlock device
558  *
559  * Evaluate device's _LCK method if present to lock/unlock device
560  */
561 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
562 {
563 	acpi_status status;
564 
565 	status = acpi_execute_simple_method(handle, "_LCK", !!lock);
566 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
567 		if (lock)
568 			acpi_handle_warn(handle,
569 				"Locking device failed (0x%x)\n", status);
570 		else
571 			acpi_handle_warn(handle,
572 				"Unlocking device failed (0x%x)\n", status);
573 	}
574 
575 	return status;
576 }
577