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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20 */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/slab.h>
25#include <linux/init.h>
26#include <linux/types.h>
27#include <linux/hardirq.h>
28#include <linux/acpi.h>
29#include <linux/dynamic_debug.h>
30
31#include "internal.h"
32
33#define _COMPONENT		ACPI_BUS_COMPONENT
34ACPI_MODULE_NAME("utils");
35
36/* --------------------------------------------------------------------------
37                            Object Evaluation Helpers
38   -------------------------------------------------------------------------- */
39static void
40acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
41{
42#ifdef ACPI_DEBUG_OUTPUT
43	char prefix[80] = {'\0'};
44	struct acpi_buffer buffer = {sizeof(prefix), prefix};
45	acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
46	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
47		(char *) prefix, p, acpi_format_exception(s)));
48#else
49	return;
50#endif
51}
52
53acpi_status
54acpi_extract_package(union acpi_object *package,
55		     struct acpi_buffer *format, struct acpi_buffer *buffer)
56{
57	u32 size_required = 0;
58	u32 tail_offset = 0;
59	char *format_string = NULL;
60	u32 format_count = 0;
61	u32 i = 0;
62	u8 *head = NULL;
63	u8 *tail = NULL;
64
65
66	if (!package || (package->type != ACPI_TYPE_PACKAGE)
67	    || (package->package.count < 1)) {
68		printk(KERN_WARNING PREFIX "Invalid package argument\n");
69		return AE_BAD_PARAMETER;
70	}
71
72	if (!format || !format->pointer || (format->length < 1)) {
73		printk(KERN_WARNING PREFIX "Invalid format argument\n");
74		return AE_BAD_PARAMETER;
75	}
76
77	if (!buffer) {
78		printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
79		return AE_BAD_PARAMETER;
80	}
81
82	format_count = (format->length / sizeof(char)) - 1;
83	if (format_count > package->package.count) {
84		printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
85			      " than exist in package [%d].\n",
86			      format_count, package->package.count);
87		return AE_BAD_DATA;
88	}
89
90	format_string = format->pointer;
91
92	/*
93	 * Calculate size_required.
94	 */
95	for (i = 0; i < format_count; i++) {
96
97		union acpi_object *element = &(package->package.elements[i]);
98
99		switch (element->type) {
100
101		case ACPI_TYPE_INTEGER:
102			switch (format_string[i]) {
103			case 'N':
104				size_required += sizeof(u64);
105				tail_offset += sizeof(u64);
106				break;
107			case 'S':
108				size_required +=
109				    sizeof(char *) + sizeof(u64) +
110				    sizeof(char);
111				tail_offset += sizeof(char *);
112				break;
113			default:
114				printk(KERN_WARNING PREFIX "Invalid package element"
115					      " [%d]: got number, expecting"
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 *) + element->buffer.length;
136				tail_offset += sizeof(u8 *);
137				break;
138			default:
139				printk(KERN_WARNING PREFIX "Invalid package element"
140					      " [%d] got string/buffer,"
141					      " expecting [%c]\n",
142					      i, format_string[i]);
143				return AE_BAD_DATA;
144				break;
145			}
146			break;
147		case ACPI_TYPE_LOCAL_REFERENCE:
148			switch (format_string[i]) {
149			case 'R':
150				size_required += sizeof(void *);
151				tail_offset += sizeof(void *);
152				break;
153			default:
154				printk(KERN_WARNING PREFIX "Invalid package element"
155					      " [%d] got reference,"
156					      " expecting [%c]\n",
157					      i, format_string[i]);
158				return AE_BAD_DATA;
159				break;
160			}
161			break;
162
163		case ACPI_TYPE_PACKAGE:
164		default:
165			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
166					  "Found unsupported element at index=%d\n",
167					  i));
168			/* TBD: handle nested packages... */
169			return AE_SUPPORT;
170			break;
171		}
172	}
173
174	/*
175	 * Validate output buffer.
176	 */
177	if (buffer->length == ACPI_ALLOCATE_BUFFER) {
178		buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
179		if (!buffer->pointer)
180			return AE_NO_MEMORY;
181		buffer->length = size_required;
182	} else {
183		if (buffer->length < size_required) {
184			buffer->length = size_required;
185			return AE_BUFFER_OVERFLOW;
186		} else if (buffer->length != size_required ||
187			   !buffer->pointer) {
188			return AE_BAD_PARAMETER;
189		}
190	}
191
192	head = buffer->pointer;
193	tail = buffer->pointer + tail_offset;
194
195	/*
196	 * Extract package data.
197	 */
198	for (i = 0; i < format_count; i++) {
199
200		u8 **pointer = NULL;
201		union acpi_object *element = &(package->package.elements[i]);
202
203		if (!element) {
204			return AE_BAD_DATA;
205		}
206
207		switch (element->type) {
208
209		case ACPI_TYPE_INTEGER:
210			switch (format_string[i]) {
211			case 'N':
212				*((u64 *) head) =
213				    element->integer.value;
214				head += sizeof(u64);
215				break;
216			case 'S':
217				pointer = (u8 **) head;
218				*pointer = tail;
219				*((u64 *) tail) =
220				    element->integer.value;
221				head += sizeof(u64 *);
222				tail += sizeof(u64);
223				/* NULL terminate string */
224				*tail = (char)0;
225				tail += sizeof(char);
226				break;
227			default:
228				/* Should never get here */
229				break;
230			}
231			break;
232
233		case ACPI_TYPE_STRING:
234		case ACPI_TYPE_BUFFER:
235			switch (format_string[i]) {
236			case 'S':
237				pointer = (u8 **) head;
238				*pointer = tail;
239				memcpy(tail, element->string.pointer,
240				       element->string.length);
241				head += sizeof(char *);
242				tail += element->string.length * sizeof(char);
243				/* NULL terminate string */
244				*tail = (char)0;
245				tail += sizeof(char);
246				break;
247			case 'B':
248				pointer = (u8 **) head;
249				*pointer = tail;
250				memcpy(tail, element->buffer.pointer,
251				       element->buffer.length);
252				head += sizeof(u8 *);
253				tail += element->buffer.length;
254				break;
255			default:
256				/* Should never get here */
257				break;
258			}
259			break;
260		case ACPI_TYPE_LOCAL_REFERENCE:
261			switch (format_string[i]) {
262			case 'R':
263				*(void **)head =
264				    (void *)element->reference.handle;
265				head += sizeof(void *);
266				break;
267			default:
268				/* Should never get here */
269				break;
270			}
271			break;
272		case ACPI_TYPE_PACKAGE:
273			/* TBD: handle nested packages... */
274		default:
275			/* Should never get here */
276			break;
277		}
278	}
279
280	return AE_OK;
281}
282
283EXPORT_SYMBOL(acpi_extract_package);
284
285acpi_status
286acpi_evaluate_integer(acpi_handle handle,
287		      acpi_string pathname,
288		      struct acpi_object_list *arguments, unsigned long long *data)
289{
290	acpi_status status = AE_OK;
291	union acpi_object element;
292	struct acpi_buffer buffer = { 0, NULL };
293
294	if (!data)
295		return AE_BAD_PARAMETER;
296
297	buffer.length = sizeof(union acpi_object);
298	buffer.pointer = &element;
299	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
300	if (ACPI_FAILURE(status)) {
301		acpi_util_eval_error(handle, pathname, status);
302		return status;
303	}
304
305	if (element.type != ACPI_TYPE_INTEGER) {
306		acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
307		return AE_BAD_DATA;
308	}
309
310	*data = element.integer.value;
311
312	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
313
314	return AE_OK;
315}
316
317EXPORT_SYMBOL(acpi_evaluate_integer);
318
319acpi_status
320acpi_evaluate_reference(acpi_handle handle,
321			acpi_string pathname,
322			struct acpi_object_list *arguments,
323			struct acpi_handle_list *list)
324{
325	acpi_status status = AE_OK;
326	union acpi_object *package = NULL;
327	union acpi_object *element = NULL;
328	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
329	u32 i = 0;
330
331
332	if (!list) {
333		return AE_BAD_PARAMETER;
334	}
335
336	/* Evaluate object. */
337
338	status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
339	if (ACPI_FAILURE(status))
340		goto end;
341
342	package = buffer.pointer;
343
344	if ((buffer.length == 0) || !package) {
345		status = AE_BAD_DATA;
346		acpi_util_eval_error(handle, pathname, status);
347		goto end;
348	}
349	if (package->type != ACPI_TYPE_PACKAGE) {
350		status = AE_BAD_DATA;
351		acpi_util_eval_error(handle, pathname, status);
352		goto end;
353	}
354	if (!package->package.count) {
355		status = AE_BAD_DATA;
356		acpi_util_eval_error(handle, pathname, status);
357		goto end;
358	}
359
360	if (package->package.count > ACPI_MAX_HANDLES) {
361		return AE_NO_MEMORY;
362	}
363	list->count = package->package.count;
364
365	/* Extract package data. */
366
367	for (i = 0; i < list->count; i++) {
368
369		element = &(package->package.elements[i]);
370
371		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
372			status = AE_BAD_DATA;
373			acpi_util_eval_error(handle, pathname, status);
374			break;
375		}
376
377		if (!element->reference.handle) {
378			status = AE_NULL_ENTRY;
379			acpi_util_eval_error(handle, pathname, status);
380			break;
381		}
382		/* Get the  acpi_handle. */
383
384		list->handles[i] = element->reference.handle;
385		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
386				  list->handles[i]));
387	}
388
389      end:
390	if (ACPI_FAILURE(status)) {
391		list->count = 0;
392		//kfree(list->handles);
393	}
394
395	kfree(buffer.pointer);
396
397	return status;
398}
399
400EXPORT_SYMBOL(acpi_evaluate_reference);
401
402acpi_status
403acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
404{
405	acpi_status status;
406	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
407	union acpi_object *output;
408
409	status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
410
411	if (ACPI_FAILURE(status))
412		return status;
413
414	output = buffer.pointer;
415
416	if (!output || output->type != ACPI_TYPE_PACKAGE
417	    || !output->package.count
418	    || output->package.elements[0].type != ACPI_TYPE_BUFFER
419	    || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
420		status = AE_TYPE;
421		goto out;
422	}
423
424	status = acpi_decode_pld_buffer(
425			output->package.elements[0].buffer.pointer,
426			output->package.elements[0].buffer.length,
427			pld);
428
429out:
430	kfree(buffer.pointer);
431	return status;
432}
433EXPORT_SYMBOL(acpi_get_physical_device_location);
434
435/**
436 * acpi_evaluate_ost: Evaluate _OST for hotplug operations
437 * @handle: ACPI device handle
438 * @source_event: source event code
439 * @status_code: status code
440 * @status_buf: optional detailed information (NULL if none)
441 *
442 * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
443 * must call this function when evaluating _OST for hotplug operations.
444 * When the platform does not support _OST, this function has no effect.
445 */
446acpi_status
447acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
448		  struct acpi_buffer *status_buf)
449{
450	union acpi_object params[3] = {
451		{.type = ACPI_TYPE_INTEGER,},
452		{.type = ACPI_TYPE_INTEGER,},
453		{.type = ACPI_TYPE_BUFFER,}
454	};
455	struct acpi_object_list arg_list = {3, params};
456
457	params[0].integer.value = source_event;
458	params[1].integer.value = status_code;
459	if (status_buf != NULL) {
460		params[2].buffer.pointer = status_buf->pointer;
461		params[2].buffer.length = status_buf->length;
462	} else {
463		params[2].buffer.pointer = NULL;
464		params[2].buffer.length = 0;
465	}
466
467	return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
468}
469EXPORT_SYMBOL(acpi_evaluate_ost);
470
471/**
472 * acpi_handle_path: Return the object path of handle
473 *
474 * Caller must free the returned buffer
475 */
476static char *acpi_handle_path(acpi_handle handle)
477{
478	struct acpi_buffer buffer = {
479		.length = ACPI_ALLOCATE_BUFFER,
480		.pointer = NULL
481	};
482
483	if (in_interrupt() ||
484	    acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
485		return NULL;
486	return buffer.pointer;
487}
488
489/**
490 * acpi_handle_printk: Print message with ACPI prefix and object path
491 *
492 * This function is called through acpi_handle_<level> macros and prints
493 * a message with ACPI prefix and object path.  This function acquires
494 * the global namespace mutex to obtain an object path.  In interrupt
495 * context, it shows the object path as <n/a>.
496 */
497void
498acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
499{
500	struct va_format vaf;
501	va_list args;
502	const char *path;
503
504	va_start(args, fmt);
505	vaf.fmt = fmt;
506	vaf.va = &args;
507
508	path = acpi_handle_path(handle);
509	printk("%sACPI: %s: %pV", level, path ? path : "<n/a>" , &vaf);
510
511	va_end(args);
512	kfree(path);
513}
514EXPORT_SYMBOL(acpi_handle_printk);
515
516#if defined(CONFIG_DYNAMIC_DEBUG)
517/**
518 * __acpi_handle_debug: pr_debug with ACPI prefix and object path
519 *
520 * This function is called through acpi_handle_debug macro and debug
521 * prints a message with ACPI prefix and object path. This function
522 * acquires the global namespace mutex to obtain an object path.  In
523 * interrupt context, it shows the object path as <n/a>.
524 */
525void
526__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
527		    const char *fmt, ...)
528{
529	struct va_format vaf;
530	va_list args;
531	const char *path;
532
533	va_start(args, fmt);
534	vaf.fmt = fmt;
535	vaf.va = &args;
536
537	path = acpi_handle_path(handle);
538	__dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
539
540	va_end(args);
541	kfree(path);
542}
543EXPORT_SYMBOL(__acpi_handle_debug);
544#endif
545
546/**
547 * acpi_has_method: Check whether @handle has a method named @name
548 * @handle: ACPI device handle
549 * @name: name of object or method
550 *
551 * Check whether @handle has a method named @name.
552 */
553bool acpi_has_method(acpi_handle handle, char *name)
554{
555	acpi_handle tmp;
556
557	return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
558}
559EXPORT_SYMBOL(acpi_has_method);
560
561acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
562				       u64 arg)
563{
564	union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
565	struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
566
567	obj.integer.value = arg;
568
569	return acpi_evaluate_object(handle, method, &arg_list, NULL);
570}
571EXPORT_SYMBOL(acpi_execute_simple_method);
572
573/**
574 * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
575 * @handle: ACPI device handle
576 *
577 * Evaluate device's _EJ0 method for hotplug operations.
578 */
579acpi_status acpi_evaluate_ej0(acpi_handle handle)
580{
581	acpi_status status;
582
583	status = acpi_execute_simple_method(handle, "_EJ0", 1);
584	if (status == AE_NOT_FOUND)
585		acpi_handle_warn(handle, "No _EJ0 support for device\n");
586	else if (ACPI_FAILURE(status))
587		acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
588
589	return status;
590}
591
592/**
593 * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
594 * @handle: ACPI device handle
595 * @lock: lock device if non-zero, otherwise unlock device
596 *
597 * Evaluate device's _LCK method if present to lock/unlock device
598 */
599acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
600{
601	acpi_status status;
602
603	status = acpi_execute_simple_method(handle, "_LCK", !!lock);
604	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
605		if (lock)
606			acpi_handle_warn(handle,
607				"Locking device failed (0x%x)\n", status);
608		else
609			acpi_handle_warn(handle,
610				"Unlocking device failed (0x%x)\n", status);
611	}
612
613	return status;
614}
615
616/**
617 * acpi_evaluate_dsm - evaluate device's _DSM method
618 * @handle: ACPI device handle
619 * @uuid: UUID of requested functions, should be 16 bytes
620 * @rev: revision number of requested function
621 * @func: requested function number
622 * @argv4: the function specific parameter
623 *
624 * Evaluate device's _DSM method with specified UUID, revision id and
625 * function number. Caller needs to free the returned object.
626 *
627 * Though ACPI defines the fourth parameter for _DSM should be a package,
628 * some old BIOSes do expect a buffer or an integer etc.
629 */
630union acpi_object *
631acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
632		  union acpi_object *argv4)
633{
634	acpi_status ret;
635	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
636	union acpi_object params[4];
637	struct acpi_object_list input = {
638		.count = 4,
639		.pointer = params,
640	};
641
642	params[0].type = ACPI_TYPE_BUFFER;
643	params[0].buffer.length = 16;
644	params[0].buffer.pointer = (char *)uuid;
645	params[1].type = ACPI_TYPE_INTEGER;
646	params[1].integer.value = rev;
647	params[2].type = ACPI_TYPE_INTEGER;
648	params[2].integer.value = func;
649	if (argv4) {
650		params[3] = *argv4;
651	} else {
652		params[3].type = ACPI_TYPE_PACKAGE;
653		params[3].package.count = 0;
654		params[3].package.elements = NULL;
655	}
656
657	ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
658	if (ACPI_SUCCESS(ret))
659		return (union acpi_object *)buf.pointer;
660
661	if (ret != AE_NOT_FOUND)
662		acpi_handle_warn(handle,
663				"failed to evaluate _DSM (0x%x)\n", ret);
664
665	return NULL;
666}
667EXPORT_SYMBOL(acpi_evaluate_dsm);
668
669/**
670 * acpi_check_dsm - check if _DSM method supports requested functions.
671 * @handle: ACPI device handle
672 * @uuid: UUID of requested functions, should be 16 bytes at least
673 * @rev: revision number of requested functions
674 * @funcs: bitmap of requested functions
675 *
676 * Evaluate device's _DSM method to check whether it supports requested
677 * functions. Currently only support 64 functions at maximum, should be
678 * enough for now.
679 */
680bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
681{
682	int i;
683	u64 mask = 0;
684	union acpi_object *obj;
685
686	if (funcs == 0)
687		return false;
688
689	obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
690	if (!obj)
691		return false;
692
693	/* For compatibility, old BIOSes may return an integer */
694	if (obj->type == ACPI_TYPE_INTEGER)
695		mask = obj->integer.value;
696	else if (obj->type == ACPI_TYPE_BUFFER)
697		for (i = 0; i < obj->buffer.length && i < 8; i++)
698			mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
699	ACPI_FREE(obj);
700
701	/*
702	 * Bit 0 indicates whether there's support for any functions other than
703	 * function 0 for the specified UUID and revision.
704	 */
705	if ((mask & 0x1) && (mask & funcs) == funcs)
706		return true;
707
708	return false;
709}
710EXPORT_SYMBOL(acpi_check_dsm);
711
712/*
713 * acpi_backlight= handling, this is done here rather then in video_detect.c
714 * because __setup cannot be used in modules.
715 */
716char acpi_video_backlight_string[16];
717EXPORT_SYMBOL(acpi_video_backlight_string);
718
719static int __init acpi_backlight(char *str)
720{
721	strlcpy(acpi_video_backlight_string, str,
722		sizeof(acpi_video_backlight_string));
723	return 1;
724}
725__setup("acpi_backlight=", acpi_backlight);
726