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 <linux/dynamic_debug.h>
34
35#include "internal.h"
36
37#define _COMPONENT		ACPI_BUS_COMPONENT
38ACPI_MODULE_NAME("utils");
39
40/* --------------------------------------------------------------------------
41                            Object Evaluation Helpers
42   -------------------------------------------------------------------------- */
43static void
44acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
45{
46#ifdef ACPI_DEBUG_OUTPUT
47	char prefix[80] = {'\0'};
48	struct acpi_buffer buffer = {sizeof(prefix), prefix};
49	acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
50	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
51		(char *) prefix, p, acpi_format_exception(s)));
52#else
53	return;
54#endif
55}
56
57acpi_status
58acpi_extract_package(union acpi_object *package,
59		     struct acpi_buffer *format, struct acpi_buffer *buffer)
60{
61	u32 size_required = 0;
62	u32 tail_offset = 0;
63	char *format_string = NULL;
64	u32 format_count = 0;
65	u32 i = 0;
66	u8 *head = NULL;
67	u8 *tail = NULL;
68
69
70	if (!package || (package->type != ACPI_TYPE_PACKAGE)
71	    || (package->package.count < 1)) {
72		printk(KERN_WARNING PREFIX "Invalid package argument\n");
73		return AE_BAD_PARAMETER;
74	}
75
76	if (!format || !format->pointer || (format->length < 1)) {
77		printk(KERN_WARNING PREFIX "Invalid format argument\n");
78		return AE_BAD_PARAMETER;
79	}
80
81	if (!buffer) {
82		printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
83		return AE_BAD_PARAMETER;
84	}
85
86	format_count = (format->length / sizeof(char)) - 1;
87	if (format_count > package->package.count) {
88		printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
89			      " than exist in package [%d].\n",
90			      format_count, package->package.count);
91		return AE_BAD_DATA;
92	}
93
94	format_string = format->pointer;
95
96	/*
97	 * Calculate size_required.
98	 */
99	for (i = 0; i < format_count; i++) {
100
101		union acpi_object *element = &(package->package.elements[i]);
102
103		switch (element->type) {
104
105		case ACPI_TYPE_INTEGER:
106			switch (format_string[i]) {
107			case 'N':
108				size_required += sizeof(u64);
109				tail_offset += sizeof(u64);
110				break;
111			case 'S':
112				size_required +=
113				    sizeof(char *) + sizeof(u64) +
114				    sizeof(char);
115				tail_offset += sizeof(char *);
116				break;
117			default:
118				printk(KERN_WARNING PREFIX "Invalid package element"
119					      " [%d]: got number, expecting"
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					      " expecting [%c]\n",
147					      i, format_string[i]);
148				return AE_BAD_DATA;
149				break;
150			}
151			break;
152		case ACPI_TYPE_LOCAL_REFERENCE:
153			switch (format_string[i]) {
154			case 'R':
155				size_required += sizeof(void *);
156				tail_offset += sizeof(void *);
157				break;
158			default:
159				printk(KERN_WARNING PREFIX "Invalid package element"
160					      " [%d] got reference,"
161					      " expecting [%c]\n",
162					      i, format_string[i]);
163				return AE_BAD_DATA;
164				break;
165			}
166			break;
167
168		case ACPI_TYPE_PACKAGE:
169		default:
170			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
171					  "Found unsupported element at index=%d\n",
172					  i));
173			/* TBD: handle nested packages... */
174			return AE_SUPPORT;
175			break;
176		}
177	}
178
179	/*
180	 * Validate output buffer.
181	 */
182	if (buffer->length == ACPI_ALLOCATE_BUFFER) {
183		buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
184		if (!buffer->pointer)
185			return AE_NO_MEMORY;
186		buffer->length = size_required;
187	} else {
188		if (buffer->length < size_required) {
189			buffer->length = size_required;
190			return AE_BUFFER_OVERFLOW;
191		} else if (buffer->length != size_required ||
192			   !buffer->pointer) {
193			return AE_BAD_PARAMETER;
194		}
195	}
196
197	head = buffer->pointer;
198	tail = buffer->pointer + tail_offset;
199
200	/*
201	 * Extract package data.
202	 */
203	for (i = 0; i < format_count; i++) {
204
205		u8 **pointer = NULL;
206		union acpi_object *element = &(package->package.elements[i]);
207
208		if (!element) {
209			return AE_BAD_DATA;
210		}
211
212		switch (element->type) {
213
214		case ACPI_TYPE_INTEGER:
215			switch (format_string[i]) {
216			case 'N':
217				*((u64 *) head) =
218				    element->integer.value;
219				head += sizeof(u64);
220				break;
221			case 'S':
222				pointer = (u8 **) head;
223				*pointer = tail;
224				*((u64 *) tail) =
225				    element->integer.value;
226				head += sizeof(u64 *);
227				tail += sizeof(u64);
228				/* NULL terminate string */
229				*tail = (char)0;
230				tail += sizeof(char);
231				break;
232			default:
233				/* Should never get here */
234				break;
235			}
236			break;
237
238		case ACPI_TYPE_STRING:
239		case ACPI_TYPE_BUFFER:
240			switch (format_string[i]) {
241			case 'S':
242				pointer = (u8 **) head;
243				*pointer = tail;
244				memcpy(tail, element->string.pointer,
245				       element->string.length);
246				head += sizeof(char *);
247				tail += element->string.length * sizeof(char);
248				/* NULL terminate string */
249				*tail = (char)0;
250				tail += sizeof(char);
251				break;
252			case 'B':
253				pointer = (u8 **) head;
254				*pointer = tail;
255				memcpy(tail, element->buffer.pointer,
256				       element->buffer.length);
257				head += sizeof(u8 *);
258				tail += element->buffer.length * sizeof(u8);
259				break;
260			default:
261				/* Should never get here */
262				break;
263			}
264			break;
265		case ACPI_TYPE_LOCAL_REFERENCE:
266			switch (format_string[i]) {
267			case 'R':
268				*(void **)head =
269				    (void *)element->reference.handle;
270				head += sizeof(void *);
271				break;
272			default:
273				/* Should never get here */
274				break;
275			}
276			break;
277		case ACPI_TYPE_PACKAGE:
278			/* TBD: handle nested packages... */
279		default:
280			/* Should never get here */
281			break;
282		}
283	}
284
285	return AE_OK;
286}
287
288EXPORT_SYMBOL(acpi_extract_package);
289
290acpi_status
291acpi_evaluate_integer(acpi_handle handle,
292		      acpi_string pathname,
293		      struct acpi_object_list *arguments, unsigned long long *data)
294{
295	acpi_status status = AE_OK;
296	union acpi_object element;
297	struct acpi_buffer buffer = { 0, NULL };
298
299	if (!data)
300		return AE_BAD_PARAMETER;
301
302	buffer.length = sizeof(union acpi_object);
303	buffer.pointer = &element;
304	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
305	if (ACPI_FAILURE(status)) {
306		acpi_util_eval_error(handle, pathname, status);
307		return status;
308	}
309
310	if (element.type != ACPI_TYPE_INTEGER) {
311		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
312		return AE_BAD_DATA;
313	}
314
315	*data = element.integer.value;
316
317	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
318
319	return AE_OK;
320}
321
322EXPORT_SYMBOL(acpi_evaluate_integer);
323
324acpi_status
325acpi_evaluate_reference(acpi_handle handle,
326			acpi_string pathname,
327			struct acpi_object_list *arguments,
328			struct acpi_handle_list *list)
329{
330	acpi_status status = AE_OK;
331	union acpi_object *package = NULL;
332	union acpi_object *element = NULL;
333	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
334	u32 i = 0;
335
336
337	if (!list) {
338		return AE_BAD_PARAMETER;
339	}
340
341	/* Evaluate object. */
342
343	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
344	if (ACPI_FAILURE(status))
345		goto end;
346
347	package = buffer.pointer;
348
349	if ((buffer.length == 0) || !package) {
350		printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
351			    (unsigned)buffer.length, package);
352		status = AE_BAD_DATA;
353		acpi_util_eval_error(handle, pathname, status);
354		goto end;
355	}
356	if (package->type != ACPI_TYPE_PACKAGE) {
357		printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
358			    package->type);
359		status = AE_BAD_DATA;
360		acpi_util_eval_error(handle, pathname, status);
361		goto end;
362	}
363	if (!package->package.count) {
364		printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
365			    package);
366		status = AE_BAD_DATA;
367		acpi_util_eval_error(handle, pathname, status);
368		goto end;
369	}
370
371	if (package->package.count > ACPI_MAX_HANDLES) {
372		return AE_NO_MEMORY;
373	}
374	list->count = package->package.count;
375
376	/* Extract package data. */
377
378	for (i = 0; i < list->count; i++) {
379
380		element = &(package->package.elements[i]);
381
382		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
383			status = AE_BAD_DATA;
384			printk(KERN_ERR PREFIX
385				    "Expecting a [Reference] package element, found type %X\n",
386				    element->type);
387			acpi_util_eval_error(handle, pathname, status);
388			break;
389		}
390
391		if (!element->reference.handle) {
392			printk(KERN_WARNING PREFIX "Invalid reference in"
393			       " package %s\n", pathname);
394			status = AE_NULL_ENTRY;
395			break;
396		}
397		/* Get the  acpi_handle. */
398
399		list->handles[i] = element->reference.handle;
400		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
401				  list->handles[i]));
402	}
403
404      end:
405	if (ACPI_FAILURE(status)) {
406		list->count = 0;
407		//kfree(list->handles);
408	}
409
410	kfree(buffer.pointer);
411
412	return status;
413}
414
415EXPORT_SYMBOL(acpi_evaluate_reference);
416
417acpi_status
418acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
419{
420	acpi_status status;
421	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
422	union acpi_object *output;
423
424	status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
425
426	if (ACPI_FAILURE(status))
427		return status;
428
429	output = buffer.pointer;
430
431	if (!output || output->type != ACPI_TYPE_PACKAGE
432	    || !output->package.count
433	    || output->package.elements[0].type != ACPI_TYPE_BUFFER
434	    || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
435		status = AE_TYPE;
436		goto out;
437	}
438
439	status = acpi_decode_pld_buffer(
440			output->package.elements[0].buffer.pointer,
441			output->package.elements[0].buffer.length,
442			pld);
443
444out:
445	kfree(buffer.pointer);
446	return status;
447}
448EXPORT_SYMBOL(acpi_get_physical_device_location);
449
450/**
451 * acpi_evaluate_ost: Evaluate _OST for hotplug operations
452 * @handle: ACPI device handle
453 * @source_event: source event code
454 * @status_code: status code
455 * @status_buf: optional detailed information (NULL if none)
456 *
457 * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
458 * must call this function when evaluating _OST for hotplug operations.
459 * When the platform does not support _OST, this function has no effect.
460 */
461acpi_status
462acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
463		  struct acpi_buffer *status_buf)
464{
465	union acpi_object params[3] = {
466		{.type = ACPI_TYPE_INTEGER,},
467		{.type = ACPI_TYPE_INTEGER,},
468		{.type = ACPI_TYPE_BUFFER,}
469	};
470	struct acpi_object_list arg_list = {3, params};
471
472	params[0].integer.value = source_event;
473	params[1].integer.value = status_code;
474	if (status_buf != NULL) {
475		params[2].buffer.pointer = status_buf->pointer;
476		params[2].buffer.length = status_buf->length;
477	} else {
478		params[2].buffer.pointer = NULL;
479		params[2].buffer.length = 0;
480	}
481
482	return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
483}
484EXPORT_SYMBOL(acpi_evaluate_ost);
485
486/**
487 * acpi_handle_path: Return the object path of handle
488 *
489 * Caller must free the returned buffer
490 */
491static char *acpi_handle_path(acpi_handle handle)
492{
493	struct acpi_buffer buffer = {
494		.length = ACPI_ALLOCATE_BUFFER,
495		.pointer = NULL
496	};
497
498	if (in_interrupt() ||
499	    acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
500		return NULL;
501	return buffer.pointer;
502}
503
504/**
505 * acpi_handle_printk: Print message with ACPI prefix and object path
506 *
507 * This function is called through acpi_handle_<level> macros and prints
508 * a message with ACPI prefix and object path.  This function acquires
509 * the global namespace mutex to obtain an object path.  In interrupt
510 * context, it shows the object path as <n/a>.
511 */
512void
513acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
514{
515	struct va_format vaf;
516	va_list args;
517	const char *path;
518
519	va_start(args, fmt);
520	vaf.fmt = fmt;
521	vaf.va = &args;
522
523	path = acpi_handle_path(handle);
524	printk("%sACPI: %s: %pV", level, path ? path : "<n/a>" , &vaf);
525
526	va_end(args);
527	kfree(path);
528}
529EXPORT_SYMBOL(acpi_handle_printk);
530
531#if defined(CONFIG_DYNAMIC_DEBUG)
532/**
533 * __acpi_handle_debug: pr_debug with ACPI prefix and object path
534 *
535 * This function is called through acpi_handle_debug macro and debug
536 * prints a message with ACPI prefix and object path. This function
537 * acquires the global namespace mutex to obtain an object path.  In
538 * interrupt context, it shows the object path as <n/a>.
539 */
540void
541__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
542		    const char *fmt, ...)
543{
544	struct va_format vaf;
545	va_list args;
546	const char *path;
547
548	va_start(args, fmt);
549	vaf.fmt = fmt;
550	vaf.va = &args;
551
552	path = acpi_handle_path(handle);
553	__dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
554
555	va_end(args);
556	kfree(path);
557}
558EXPORT_SYMBOL(__acpi_handle_debug);
559#endif
560
561/**
562 * acpi_has_method: Check whether @handle has a method named @name
563 * @handle: ACPI device handle
564 * @name: name of object or method
565 *
566 * Check whether @handle has a method named @name.
567 */
568bool acpi_has_method(acpi_handle handle, char *name)
569{
570	acpi_handle tmp;
571
572	return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
573}
574EXPORT_SYMBOL(acpi_has_method);
575
576acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
577				       u64 arg)
578{
579	union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
580	struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
581
582	obj.integer.value = arg;
583
584	return acpi_evaluate_object(handle, method, &arg_list, NULL);
585}
586EXPORT_SYMBOL(acpi_execute_simple_method);
587
588/**
589 * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
590 * @handle: ACPI device handle
591 *
592 * Evaluate device's _EJ0 method for hotplug operations.
593 */
594acpi_status acpi_evaluate_ej0(acpi_handle handle)
595{
596	acpi_status status;
597
598	status = acpi_execute_simple_method(handle, "_EJ0", 1);
599	if (status == AE_NOT_FOUND)
600		acpi_handle_warn(handle, "No _EJ0 support for device\n");
601	else if (ACPI_FAILURE(status))
602		acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
603
604	return status;
605}
606
607/**
608 * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
609 * @handle: ACPI device handle
610 * @lock: lock device if non-zero, otherwise unlock device
611 *
612 * Evaluate device's _LCK method if present to lock/unlock device
613 */
614acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
615{
616	acpi_status status;
617
618	status = acpi_execute_simple_method(handle, "_LCK", !!lock);
619	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
620		if (lock)
621			acpi_handle_warn(handle,
622				"Locking device failed (0x%x)\n", status);
623		else
624			acpi_handle_warn(handle,
625				"Unlocking device failed (0x%x)\n", status);
626	}
627
628	return status;
629}
630
631/**
632 * acpi_evaluate_dsm - evaluate device's _DSM method
633 * @handle: ACPI device handle
634 * @uuid: UUID of requested functions, should be 16 bytes
635 * @rev: revision number of requested function
636 * @func: requested function number
637 * @argv4: the function specific parameter
638 *
639 * Evaluate device's _DSM method with specified UUID, revision id and
640 * function number. Caller needs to free the returned object.
641 *
642 * Though ACPI defines the fourth parameter for _DSM should be a package,
643 * some old BIOSes do expect a buffer or an integer etc.
644 */
645union acpi_object *
646acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
647		  union acpi_object *argv4)
648{
649	acpi_status ret;
650	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
651	union acpi_object params[4];
652	struct acpi_object_list input = {
653		.count = 4,
654		.pointer = params,
655	};
656
657	params[0].type = ACPI_TYPE_BUFFER;
658	params[0].buffer.length = 16;
659	params[0].buffer.pointer = (char *)uuid;
660	params[1].type = ACPI_TYPE_INTEGER;
661	params[1].integer.value = rev;
662	params[2].type = ACPI_TYPE_INTEGER;
663	params[2].integer.value = func;
664	if (argv4) {
665		params[3] = *argv4;
666	} else {
667		params[3].type = ACPI_TYPE_PACKAGE;
668		params[3].package.count = 0;
669		params[3].package.elements = NULL;
670	}
671
672	ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
673	if (ACPI_SUCCESS(ret))
674		return (union acpi_object *)buf.pointer;
675
676	if (ret != AE_NOT_FOUND)
677		acpi_handle_warn(handle,
678				"failed to evaluate _DSM (0x%x)\n", ret);
679
680	return NULL;
681}
682EXPORT_SYMBOL(acpi_evaluate_dsm);
683
684/**
685 * acpi_check_dsm - check if _DSM method supports requested functions.
686 * @handle: ACPI device handle
687 * @uuid: UUID of requested functions, should be 16 bytes at least
688 * @rev: revision number of requested functions
689 * @funcs: bitmap of requested functions
690 *
691 * Evaluate device's _DSM method to check whether it supports requested
692 * functions. Currently only support 64 functions at maximum, should be
693 * enough for now.
694 */
695bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
696{
697	int i;
698	u64 mask = 0;
699	union acpi_object *obj;
700
701	if (funcs == 0)
702		return false;
703
704	obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
705	if (!obj)
706		return false;
707
708	/* For compatibility, old BIOSes may return an integer */
709	if (obj->type == ACPI_TYPE_INTEGER)
710		mask = obj->integer.value;
711	else if (obj->type == ACPI_TYPE_BUFFER)
712		for (i = 0; i < obj->buffer.length && i < 8; i++)
713			mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
714	ACPI_FREE(obj);
715
716	/*
717	 * Bit 0 indicates whether there's support for any functions other than
718	 * function 0 for the specified UUID and revision.
719	 */
720	if ((mask & 0x1) && (mask & funcs) == funcs)
721		return true;
722
723	return false;
724}
725EXPORT_SYMBOL(acpi_check_dsm);
726