xref: /openbmc/linux/drivers/acpi/utils.c (revision 874b8d42)
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 
34 #include "internal.h"
35 
36 #define _COMPONENT		ACPI_BUS_COMPONENT
37 ACPI_MODULE_NAME("utils");
38 
39 /* --------------------------------------------------------------------------
40                             Object Evaluation Helpers
41    -------------------------------------------------------------------------- */
42 static void
43 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
44 {
45 #ifdef ACPI_DEBUG_OUTPUT
46 	char prefix[80] = {'\0'};
47 	struct acpi_buffer buffer = {sizeof(prefix), prefix};
48 	acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
49 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
50 		(char *) prefix, p, acpi_format_exception(s)));
51 #else
52 	return;
53 #endif
54 }
55 
56 acpi_status
57 acpi_extract_package(union acpi_object *package,
58 		     struct acpi_buffer *format, struct acpi_buffer *buffer)
59 {
60 	u32 size_required = 0;
61 	u32 tail_offset = 0;
62 	char *format_string = NULL;
63 	u32 format_count = 0;
64 	u32 i = 0;
65 	u8 *head = NULL;
66 	u8 *tail = NULL;
67 
68 
69 	if (!package || (package->type != ACPI_TYPE_PACKAGE)
70 	    || (package->package.count < 1)) {
71 		printk(KERN_WARNING PREFIX "Invalid package argument\n");
72 		return AE_BAD_PARAMETER;
73 	}
74 
75 	if (!format || !format->pointer || (format->length < 1)) {
76 		printk(KERN_WARNING PREFIX "Invalid format argument\n");
77 		return AE_BAD_PARAMETER;
78 	}
79 
80 	if (!buffer) {
81 		printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
82 		return AE_BAD_PARAMETER;
83 	}
84 
85 	format_count = (format->length / sizeof(char)) - 1;
86 	if (format_count > package->package.count) {
87 		printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
88 			      " than exist in package [%d].\n",
89 			      format_count, package->package.count);
90 		return AE_BAD_DATA;
91 	}
92 
93 	format_string = format->pointer;
94 
95 	/*
96 	 * Calculate size_required.
97 	 */
98 	for (i = 0; i < format_count; i++) {
99 
100 		union acpi_object *element = &(package->package.elements[i]);
101 
102 		if (!element) {
103 			return AE_BAD_DATA;
104 		}
105 
106 		switch (element->type) {
107 
108 		case ACPI_TYPE_INTEGER:
109 			switch (format_string[i]) {
110 			case 'N':
111 				size_required += sizeof(u64);
112 				tail_offset += sizeof(u64);
113 				break;
114 			case 'S':
115 				size_required +=
116 				    sizeof(char *) + sizeof(u64) +
117 				    sizeof(char);
118 				tail_offset += sizeof(char *);
119 				break;
120 			default:
121 				printk(KERN_WARNING PREFIX "Invalid package element"
122 					      " [%d]: got number, expecting"
123 					      " [%c]\n",
124 					      i, format_string[i]);
125 				return AE_BAD_DATA;
126 				break;
127 			}
128 			break;
129 
130 		case ACPI_TYPE_STRING:
131 		case ACPI_TYPE_BUFFER:
132 			switch (format_string[i]) {
133 			case 'S':
134 				size_required +=
135 				    sizeof(char *) +
136 				    (element->string.length * sizeof(char)) +
137 				    sizeof(char);
138 				tail_offset += sizeof(char *);
139 				break;
140 			case 'B':
141 				size_required +=
142 				    sizeof(u8 *) +
143 				    (element->buffer.length * sizeof(u8));
144 				tail_offset += sizeof(u8 *);
145 				break;
146 			default:
147 				printk(KERN_WARNING PREFIX "Invalid package element"
148 					      " [%d] got string/buffer,"
149 					      " expecting [%c]\n",
150 					      i, format_string[i]);
151 				return AE_BAD_DATA;
152 				break;
153 			}
154 			break;
155 
156 		case ACPI_TYPE_PACKAGE:
157 		default:
158 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
159 					  "Found unsupported element at index=%d\n",
160 					  i));
161 			/* TBD: handle nested packages... */
162 			return AE_SUPPORT;
163 			break;
164 		}
165 	}
166 
167 	/*
168 	 * Validate output buffer.
169 	 */
170 	if (buffer->length == ACPI_ALLOCATE_BUFFER) {
171 		buffer->pointer = ACPI_ALLOCATE(size_required);
172 		if (!buffer->pointer)
173 			return AE_NO_MEMORY;
174 		buffer->length = size_required;
175 		memset(buffer->pointer, 0, size_required);
176 	} else {
177 		if (buffer->length < size_required) {
178 			buffer->length = size_required;
179 			return AE_BUFFER_OVERFLOW;
180 		} else if (buffer->length != size_required ||
181 			   !buffer->pointer) {
182 			return AE_BAD_PARAMETER;
183 		}
184 	}
185 
186 	head = buffer->pointer;
187 	tail = buffer->pointer + tail_offset;
188 
189 	/*
190 	 * Extract package data.
191 	 */
192 	for (i = 0; i < format_count; i++) {
193 
194 		u8 **pointer = NULL;
195 		union acpi_object *element = &(package->package.elements[i]);
196 
197 		if (!element) {
198 			return AE_BAD_DATA;
199 		}
200 
201 		switch (element->type) {
202 
203 		case ACPI_TYPE_INTEGER:
204 			switch (format_string[i]) {
205 			case 'N':
206 				*((u64 *) head) =
207 				    element->integer.value;
208 				head += sizeof(u64);
209 				break;
210 			case 'S':
211 				pointer = (u8 **) head;
212 				*pointer = tail;
213 				*((u64 *) tail) =
214 				    element->integer.value;
215 				head += sizeof(u64 *);
216 				tail += sizeof(u64);
217 				/* NULL terminate string */
218 				*tail = (char)0;
219 				tail += sizeof(char);
220 				break;
221 			default:
222 				/* Should never get here */
223 				break;
224 			}
225 			break;
226 
227 		case ACPI_TYPE_STRING:
228 		case ACPI_TYPE_BUFFER:
229 			switch (format_string[i]) {
230 			case 'S':
231 				pointer = (u8 **) head;
232 				*pointer = tail;
233 				memcpy(tail, element->string.pointer,
234 				       element->string.length);
235 				head += sizeof(char *);
236 				tail += element->string.length * sizeof(char);
237 				/* NULL terminate string */
238 				*tail = (char)0;
239 				tail += sizeof(char);
240 				break;
241 			case 'B':
242 				pointer = (u8 **) head;
243 				*pointer = tail;
244 				memcpy(tail, element->buffer.pointer,
245 				       element->buffer.length);
246 				head += sizeof(u8 *);
247 				tail += element->buffer.length * sizeof(u8);
248 				break;
249 			default:
250 				/* Should never get here */
251 				break;
252 			}
253 			break;
254 
255 		case ACPI_TYPE_PACKAGE:
256 			/* TBD: handle nested packages... */
257 		default:
258 			/* Should never get here */
259 			break;
260 		}
261 	}
262 
263 	return AE_OK;
264 }
265 
266 EXPORT_SYMBOL(acpi_extract_package);
267 
268 acpi_status
269 acpi_evaluate_integer(acpi_handle handle,
270 		      acpi_string pathname,
271 		      struct acpi_object_list *arguments, unsigned long long *data)
272 {
273 	acpi_status status = AE_OK;
274 	union acpi_object element;
275 	struct acpi_buffer buffer = { 0, NULL };
276 
277 	if (!data)
278 		return AE_BAD_PARAMETER;
279 
280 	buffer.length = sizeof(union acpi_object);
281 	buffer.pointer = &element;
282 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
283 	if (ACPI_FAILURE(status)) {
284 		acpi_util_eval_error(handle, pathname, status);
285 		return status;
286 	}
287 
288 	if (element.type != ACPI_TYPE_INTEGER) {
289 		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
290 		return AE_BAD_DATA;
291 	}
292 
293 	*data = element.integer.value;
294 
295 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
296 
297 	return AE_OK;
298 }
299 
300 EXPORT_SYMBOL(acpi_evaluate_integer);
301 
302 acpi_status
303 acpi_evaluate_reference(acpi_handle handle,
304 			acpi_string pathname,
305 			struct acpi_object_list *arguments,
306 			struct acpi_handle_list *list)
307 {
308 	acpi_status status = AE_OK;
309 	union acpi_object *package = NULL;
310 	union acpi_object *element = NULL;
311 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
312 	u32 i = 0;
313 
314 
315 	if (!list) {
316 		return AE_BAD_PARAMETER;
317 	}
318 
319 	/* Evaluate object. */
320 
321 	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
322 	if (ACPI_FAILURE(status))
323 		goto end;
324 
325 	package = buffer.pointer;
326 
327 	if ((buffer.length == 0) || !package) {
328 		printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
329 			    (unsigned)buffer.length, package);
330 		status = AE_BAD_DATA;
331 		acpi_util_eval_error(handle, pathname, status);
332 		goto end;
333 	}
334 	if (package->type != ACPI_TYPE_PACKAGE) {
335 		printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
336 			    package->type);
337 		status = AE_BAD_DATA;
338 		acpi_util_eval_error(handle, pathname, status);
339 		goto end;
340 	}
341 	if (!package->package.count) {
342 		printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
343 			    package);
344 		status = AE_BAD_DATA;
345 		acpi_util_eval_error(handle, pathname, status);
346 		goto end;
347 	}
348 
349 	if (package->package.count > ACPI_MAX_HANDLES) {
350 		return AE_NO_MEMORY;
351 	}
352 	list->count = package->package.count;
353 
354 	/* Extract package data. */
355 
356 	for (i = 0; i < list->count; i++) {
357 
358 		element = &(package->package.elements[i]);
359 
360 		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
361 			status = AE_BAD_DATA;
362 			printk(KERN_ERR PREFIX
363 				    "Expecting a [Reference] package element, found type %X\n",
364 				    element->type);
365 			acpi_util_eval_error(handle, pathname, status);
366 			break;
367 		}
368 
369 		if (!element->reference.handle) {
370 			printk(KERN_WARNING PREFIX "Invalid reference in"
371 			       " package %s\n", pathname);
372 			status = AE_NULL_ENTRY;
373 			break;
374 		}
375 		/* Get the  acpi_handle. */
376 
377 		list->handles[i] = element->reference.handle;
378 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
379 				  list->handles[i]));
380 	}
381 
382       end:
383 	if (ACPI_FAILURE(status)) {
384 		list->count = 0;
385 		//kfree(list->handles);
386 	}
387 
388 	kfree(buffer.pointer);
389 
390 	return status;
391 }
392 
393 EXPORT_SYMBOL(acpi_evaluate_reference);
394 
395 acpi_status
396 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
397 {
398 	acpi_status status;
399 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
400 	union acpi_object *output;
401 
402 	status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
403 
404 	if (ACPI_FAILURE(status))
405 		return status;
406 
407 	output = buffer.pointer;
408 
409 	if (!output || output->type != ACPI_TYPE_PACKAGE
410 	    || !output->package.count
411 	    || output->package.elements[0].type != ACPI_TYPE_BUFFER
412 	    || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
413 		status = AE_TYPE;
414 		goto out;
415 	}
416 
417 	status = acpi_decode_pld_buffer(
418 			output->package.elements[0].buffer.pointer,
419 			output->package.elements[0].buffer.length,
420 			pld);
421 
422 out:
423 	kfree(buffer.pointer);
424 	return status;
425 }
426 EXPORT_SYMBOL(acpi_get_physical_device_location);
427 
428 /**
429  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
430  * @handle: ACPI device handle
431  * @source_event: source event code
432  * @status_code: status code
433  * @status_buf: optional detailed information (NULL if none)
434  *
435  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
436  * must call this function when evaluating _OST for hotplug operations.
437  * When the platform does not support _OST, this function has no effect.
438  */
439 acpi_status
440 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
441 		u32 status_code, struct acpi_buffer *status_buf)
442 {
443 #ifdef ACPI_HOTPLUG_OST
444 	union acpi_object params[3] = {
445 		{.type = ACPI_TYPE_INTEGER,},
446 		{.type = ACPI_TYPE_INTEGER,},
447 		{.type = ACPI_TYPE_BUFFER,}
448 	};
449 	struct acpi_object_list arg_list = {3, params};
450 	acpi_status status;
451 
452 	params[0].integer.value = source_event;
453 	params[1].integer.value = status_code;
454 	if (status_buf != NULL) {
455 		params[2].buffer.pointer = status_buf->pointer;
456 		params[2].buffer.length = status_buf->length;
457 	} else {
458 		params[2].buffer.pointer = NULL;
459 		params[2].buffer.length = 0;
460 	}
461 
462 	status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
463 	return status;
464 #else
465 	return AE_OK;
466 #endif
467 }
468 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
469 
470 /**
471  * acpi_handle_printk: Print message with ACPI prefix and object path
472  *
473  * This function is called through acpi_handle_<level> macros and prints
474  * a message with ACPI prefix and object path.  This function acquires
475  * the global namespace mutex to obtain an object path.  In interrupt
476  * context, it shows the object path as <n/a>.
477  */
478 void
479 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
480 {
481 	struct va_format vaf;
482 	va_list args;
483 	struct acpi_buffer buffer = {
484 		.length = ACPI_ALLOCATE_BUFFER,
485 		.pointer = NULL
486 	};
487 	const char *path;
488 
489 	va_start(args, fmt);
490 	vaf.fmt = fmt;
491 	vaf.va = &args;
492 
493 	if (in_interrupt() ||
494 	    acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
495 		path = "<n/a>";
496 	else
497 		path = buffer.pointer;
498 
499 	printk("%sACPI: %s: %pV", level, path, &vaf);
500 
501 	va_end(args);
502 	kfree(buffer.pointer);
503 }
504 EXPORT_SYMBOL(acpi_handle_printk);
505 
506 /**
507  * acpi_has_method: Check whether @handle has a method named @name
508  * @handle: ACPI device handle
509  * @name: name of object or method
510  *
511  * Check whether @handle has a method named @name.
512  */
513 bool acpi_has_method(acpi_handle handle, char *name)
514 {
515 	acpi_handle tmp;
516 
517 	return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
518 }
519 EXPORT_SYMBOL(acpi_has_method);
520 
521 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
522 				       u64 arg)
523 {
524 	union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
525 	struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
526 
527 	obj.integer.value = arg;
528 
529 	return acpi_evaluate_object(handle, method, &arg_list, NULL);
530 }
531 EXPORT_SYMBOL(acpi_execute_simple_method);
532 
533 /**
534  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
535  * @handle: ACPI device handle
536  *
537  * Evaluate device's _EJ0 method for hotplug operations.
538  */
539 acpi_status acpi_evaluate_ej0(acpi_handle handle)
540 {
541 	acpi_status status;
542 
543 	status = acpi_execute_simple_method(handle, "_EJ0", 1);
544 	if (status == AE_NOT_FOUND)
545 		acpi_handle_warn(handle, "No _EJ0 support for device\n");
546 	else if (ACPI_FAILURE(status))
547 		acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
548 
549 	return status;
550 }
551 
552 /**
553  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
554  * @handle: ACPI device handle
555  * @lock: lock device if non-zero, otherwise unlock device
556  *
557  * Evaluate device's _LCK method if present to lock/unlock device
558  */
559 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
560 {
561 	acpi_status status;
562 
563 	status = acpi_execute_simple_method(handle, "_LCK", !!lock);
564 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
565 		if (lock)
566 			acpi_handle_warn(handle,
567 				"Locking device failed (0x%x)\n", status);
568 		else
569 			acpi_handle_warn(handle,
570 				"Unlocking device failed (0x%x)\n", status);
571 	}
572 
573 	return status;
574 }
575 
576 /**
577  * acpi_evaluate_dsm - evaluate device's _DSM method
578  * @handle: ACPI device handle
579  * @uuid: UUID of requested functions, should be 16 bytes
580  * @rev: revision number of requested function
581  * @func: requested function number
582  * @argv4: the function specific parameter
583  *
584  * Evaluate device's _DSM method with specified UUID, revision id and
585  * function number. Caller needs to free the returned object.
586  *
587  * Though ACPI defines the fourth parameter for _DSM should be a package,
588  * some old BIOSes do expect a buffer or an integer etc.
589  */
590 union acpi_object *
591 acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
592 		  union acpi_object *argv4)
593 {
594 	acpi_status ret;
595 	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
596 	union acpi_object params[4];
597 	struct acpi_object_list input = {
598 		.count = 4,
599 		.pointer = params,
600 	};
601 
602 	params[0].type = ACPI_TYPE_BUFFER;
603 	params[0].buffer.length = 16;
604 	params[0].buffer.pointer = (char *)uuid;
605 	params[1].type = ACPI_TYPE_INTEGER;
606 	params[1].integer.value = rev;
607 	params[2].type = ACPI_TYPE_INTEGER;
608 	params[2].integer.value = func;
609 	if (argv4) {
610 		params[3] = *argv4;
611 	} else {
612 		params[3].type = ACPI_TYPE_PACKAGE;
613 		params[3].package.count = 0;
614 		params[3].package.elements = NULL;
615 	}
616 
617 	ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
618 	if (ACPI_SUCCESS(ret))
619 		return (union acpi_object *)buf.pointer;
620 
621 	if (ret != AE_NOT_FOUND)
622 		acpi_handle_warn(handle,
623 				"failed to evaluate _DSM (0x%x)\n", ret);
624 
625 	return NULL;
626 }
627 EXPORT_SYMBOL(acpi_evaluate_dsm);
628 
629 /**
630  * acpi_check_dsm - check if _DSM method supports requested functions.
631  * @handle: ACPI device handle
632  * @uuid: UUID of requested functions, should be 16 bytes at least
633  * @rev: revision number of requested functions
634  * @funcs: bitmap of requested functions
635  * @exclude: excluding special value, used to support i915 and nouveau
636  *
637  * Evaluate device's _DSM method to check whether it supports requested
638  * functions. Currently only support 64 functions at maximum, should be
639  * enough for now.
640  */
641 bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
642 {
643 	int i;
644 	u64 mask = 0;
645 	union acpi_object *obj;
646 
647 	if (funcs == 0)
648 		return false;
649 
650 	obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
651 	if (!obj)
652 		return false;
653 
654 	/* For compatibility, old BIOSes may return an integer */
655 	if (obj->type == ACPI_TYPE_INTEGER)
656 		mask = obj->integer.value;
657 	else if (obj->type == ACPI_TYPE_BUFFER)
658 		for (i = 0; i < obj->buffer.length && i < 8; i++)
659 			mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
660 	ACPI_FREE(obj);
661 
662 	/*
663 	 * Bit 0 indicates whether there's support for any functions other than
664 	 * function 0 for the specified UUID and revision.
665 	 */
666 	if ((mask & 0x1) && (mask & funcs) == funcs)
667 		return true;
668 
669 	return false;
670 }
671 EXPORT_SYMBOL(acpi_check_dsm);
672