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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#include "sleep.h"
33
34#define _COMPONENT ACPI_BUS_COMPONENT
35ACPI_MODULE_NAME("utils");
36
37/* --------------------------------------------------------------------------
38 Object Evaluation Helpers
39 -------------------------------------------------------------------------- */
40static void
41acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
42{
43#ifdef ACPI_DEBUG_OUTPUT
44 char prefix[80] = {'\0'};
45 struct acpi_buffer buffer = {sizeof(prefix), prefix};
46 acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
47 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
48 (char *) prefix, p, acpi_format_exception(s)));
49#else
50 return;
51#endif
52}
53
54acpi_status
55acpi_extract_package(union acpi_object *package,
56 struct acpi_buffer *format, struct acpi_buffer *buffer)
57{
58 u32 size_required = 0;
59 u32 tail_offset = 0;
60 char *format_string = NULL;
61 u32 format_count = 0;
62 u32 i = 0;
63 u8 *head = NULL;
64 u8 *tail = NULL;
65
66
67 if (!package || (package->type != ACPI_TYPE_PACKAGE)
68 || (package->package.count < 1)) {
69 printk(KERN_WARNING PREFIX "Invalid package argument\n");
70 return AE_BAD_PARAMETER;
71 }
72
73 if (!format || !format->pointer || (format->length < 1)) {
74 printk(KERN_WARNING PREFIX "Invalid format argument\n");
75 return AE_BAD_PARAMETER;
76 }
77
78 if (!buffer) {
79 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
80 return AE_BAD_PARAMETER;
81 }
82
83 format_count = (format->length / sizeof(char)) - 1;
84 if (format_count > package->package.count) {
85 printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
86 " than exist in package [%d].\n",
87 format_count, package->package.count);
88 return AE_BAD_DATA;
89 }
90
91 format_string = format->pointer;
92
93 /*
94 * Calculate size_required.
95 */
96 for (i = 0; i < format_count; i++) {
97
98 union acpi_object *element = &(package->package.elements[i]);
99
100 switch (element->type) {
101
102 case ACPI_TYPE_INTEGER:
103 switch (format_string[i]) {
104 case 'N':
105 size_required += sizeof(u64);
106 tail_offset += sizeof(u64);
107 break;
108 case 'S':
109 size_required +=
110 sizeof(char *) + sizeof(u64) +
111 sizeof(char);
112 tail_offset += sizeof(char *);
113 break;
114 default:
115 printk(KERN_WARNING PREFIX "Invalid package element"
116 " [%d]: got number, expecting"
117 " [%c]\n",
118 i, format_string[i]);
119 return AE_BAD_DATA;
120 break;
121 }
122 break;
123
124 case ACPI_TYPE_STRING:
125 case ACPI_TYPE_BUFFER:
126 switch (format_string[i]) {
127 case 'S':
128 size_required +=
129 sizeof(char *) +
130 (element->string.length * sizeof(char)) +
131 sizeof(char);
132 tail_offset += sizeof(char *);
133 break;
134 case 'B':
135 size_required +=
136 sizeof(u8 *) + element->buffer.length;
137 tail_offset += sizeof(u8 *);
138 break;
139 default:
140 printk(KERN_WARNING PREFIX "Invalid package element"
141 " [%d] got string/buffer,"
142 " expecting [%c]\n",
143 i, format_string[i]);
144 return AE_BAD_DATA;
145 break;
146 }
147 break;
148 case ACPI_TYPE_LOCAL_REFERENCE:
149 switch (format_string[i]) {
150 case 'R':
151 size_required += sizeof(void *);
152 tail_offset += sizeof(void *);
153 break;
154 default:
155 printk(KERN_WARNING PREFIX "Invalid package element"
156 " [%d] got reference,"
157 " expecting [%c]\n",
158 i, format_string[i]);
159 return AE_BAD_DATA;
160 break;
161 }
162 break;
163
164 case ACPI_TYPE_PACKAGE:
165 default:
166 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
167 "Found unsupported element at index=%d\n",
168 i));
169 /* TBD: handle nested packages... */
170 return AE_SUPPORT;
171 break;
172 }
173 }
174
175 /*
176 * Validate output buffer.
177 */
178 if (buffer->length == ACPI_ALLOCATE_BUFFER) {
179 buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
180 if (!buffer->pointer)
181 return AE_NO_MEMORY;
182 buffer->length = size_required;
183 } else {
184 if (buffer->length < size_required) {
185 buffer->length = size_required;
186 return AE_BUFFER_OVERFLOW;
187 } else if (buffer->length != size_required ||
188 !buffer->pointer) {
189 return AE_BAD_PARAMETER;
190 }
191 }
192
193 head = buffer->pointer;
194 tail = buffer->pointer + tail_offset;
195
196 /*
197 * Extract package data.
198 */
199 for (i = 0; i < format_count; i++) {
200
201 u8 **pointer = NULL;
202 union acpi_object *element = &(package->package.elements[i]);
203
204 switch (element->type) {
205
206 case ACPI_TYPE_INTEGER:
207 switch (format_string[i]) {
208 case 'N':
209 *((u64 *) head) =
210 element->integer.value;
211 head += sizeof(u64);
212 break;
213 case 'S':
214 pointer = (u8 **) head;
215 *pointer = tail;
216 *((u64 *) tail) =
217 element->integer.value;
218 head += sizeof(u64 *);
219 tail += sizeof(u64);
220 /* NULL terminate string */
221 *tail = (char)0;
222 tail += sizeof(char);
223 break;
224 default:
225 /* Should never get here */
226 break;
227 }
228 break;
229
230 case ACPI_TYPE_STRING:
231 case ACPI_TYPE_BUFFER:
232 switch (format_string[i]) {
233 case 'S':
234 pointer = (u8 **) head;
235 *pointer = tail;
236 memcpy(tail, element->string.pointer,
237 element->string.length);
238 head += sizeof(char *);
239 tail += element->string.length * sizeof(char);
240 /* NULL terminate string */
241 *tail = (char)0;
242 tail += sizeof(char);
243 break;
244 case 'B':
245 pointer = (u8 **) head;
246 *pointer = tail;
247 memcpy(tail, element->buffer.pointer,
248 element->buffer.length);
249 head += sizeof(u8 *);
250 tail += element->buffer.length;
251 break;
252 default:
253 /* Should never get here */
254 break;
255 }
256 break;
257 case ACPI_TYPE_LOCAL_REFERENCE:
258 switch (format_string[i]) {
259 case 'R':
260 *(void **)head =
261 (void *)element->reference.handle;
262 head += sizeof(void *);
263 break;
264 default:
265 /* Should never get here */
266 break;
267 }
268 break;
269 case ACPI_TYPE_PACKAGE:
270 /* TBD: handle nested packages... */
271 default:
272 /* Should never get here */
273 break;
274 }
275 }
276
277 return AE_OK;
278}
279
280EXPORT_SYMBOL(acpi_extract_package);
281
282acpi_status
283acpi_evaluate_integer(acpi_handle handle,
284 acpi_string pathname,
285 struct acpi_object_list *arguments, unsigned long long *data)
286{
287 acpi_status status = AE_OK;
288 union acpi_object element;
289 struct acpi_buffer buffer = { 0, NULL };
290
291 if (!data)
292 return AE_BAD_PARAMETER;
293
294 buffer.length = sizeof(union acpi_object);
295 buffer.pointer = &element;
296 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
297 if (ACPI_FAILURE(status)) {
298 acpi_util_eval_error(handle, pathname, status);
299 return status;
300 }
301
302 if (element.type != ACPI_TYPE_INTEGER) {
303 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
304 return AE_BAD_DATA;
305 }
306
307 *data = element.integer.value;
308
309 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
310
311 return AE_OK;
312}
313
314EXPORT_SYMBOL(acpi_evaluate_integer);
315
316acpi_status
317acpi_evaluate_reference(acpi_handle handle,
318 acpi_string pathname,
319 struct acpi_object_list *arguments,
320 struct acpi_handle_list *list)
321{
322 acpi_status status = AE_OK;
323 union acpi_object *package = NULL;
324 union acpi_object *element = NULL;
325 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
326 u32 i = 0;
327
328
329 if (!list) {
330 return AE_BAD_PARAMETER;
331 }
332
333 /* Evaluate object. */
334
335 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
336 if (ACPI_FAILURE(status))
337 goto end;
338
339 package = buffer.pointer;
340
341 if ((buffer.length == 0) || !package) {
342 status = AE_BAD_DATA;
343 acpi_util_eval_error(handle, pathname, status);
344 goto end;
345 }
346 if (package->type != ACPI_TYPE_PACKAGE) {
347 status = AE_BAD_DATA;
348 acpi_util_eval_error(handle, pathname, status);
349 goto end;
350 }
351 if (!package->package.count) {
352 status = AE_BAD_DATA;
353 acpi_util_eval_error(handle, pathname, status);
354 goto end;
355 }
356
357 if (package->package.count > ACPI_MAX_HANDLES) {
358 return AE_NO_MEMORY;
359 }
360 list->count = package->package.count;
361
362 /* Extract package data. */
363
364 for (i = 0; i < list->count; i++) {
365
366 element = &(package->package.elements[i]);
367
368 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
369 status = AE_BAD_DATA;
370 acpi_util_eval_error(handle, pathname, status);
371 break;
372 }
373
374 if (!element->reference.handle) {
375 status = AE_NULL_ENTRY;
376 acpi_util_eval_error(handle, pathname, status);
377 break;
378 }
379 /* Get the acpi_handle. */
380
381 list->handles[i] = element->reference.handle;
382 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
383 list->handles[i]));
384 }
385
386 end:
387 if (ACPI_FAILURE(status)) {
388 list->count = 0;
389 //kfree(list->handles);
390 }
391
392 kfree(buffer.pointer);
393
394 return status;
395}
396
397EXPORT_SYMBOL(acpi_evaluate_reference);
398
399acpi_status
400acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
401{
402 acpi_status status;
403 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
404 union acpi_object *output;
405
406 status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
407
408 if (ACPI_FAILURE(status))
409 return status;
410
411 output = buffer.pointer;
412
413 if (!output || output->type != ACPI_TYPE_PACKAGE
414 || !output->package.count
415 || output->package.elements[0].type != ACPI_TYPE_BUFFER
416 || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
417 status = AE_TYPE;
418 goto out;
419 }
420
421 status = acpi_decode_pld_buffer(
422 output->package.elements[0].buffer.pointer,
423 output->package.elements[0].buffer.length,
424 pld);
425
426out:
427 kfree(buffer.pointer);
428 return status;
429}
430EXPORT_SYMBOL(acpi_get_physical_device_location);
431
432/**
433 * acpi_evaluate_ost: Evaluate _OST for hotplug operations
434 * @handle: ACPI device handle
435 * @source_event: source event code
436 * @status_code: status code
437 * @status_buf: optional detailed information (NULL if none)
438 *
439 * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
440 * must call this function when evaluating _OST for hotplug operations.
441 * When the platform does not support _OST, this function has no effect.
442 */
443acpi_status
444acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
445 struct acpi_buffer *status_buf)
446{
447 union acpi_object params[3] = {
448 {.type = ACPI_TYPE_INTEGER,},
449 {.type = ACPI_TYPE_INTEGER,},
450 {.type = ACPI_TYPE_BUFFER,}
451 };
452 struct acpi_object_list arg_list = {3, params};
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 return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
465}
466EXPORT_SYMBOL(acpi_evaluate_ost);
467
468/**
469 * acpi_handle_path: Return the object path of handle
470 *
471 * Caller must free the returned buffer
472 */
473static char *acpi_handle_path(acpi_handle handle)
474{
475 struct acpi_buffer buffer = {
476 .length = ACPI_ALLOCATE_BUFFER,
477 .pointer = NULL
478 };
479
480 if (in_interrupt() ||
481 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
482 return NULL;
483 return buffer.pointer;
484}
485
486/**
487 * acpi_handle_printk: Print message with ACPI prefix and object path
488 *
489 * This function is called through acpi_handle_<level> macros and prints
490 * a message with ACPI prefix and object path. This function acquires
491 * the global namespace mutex to obtain an object path. In interrupt
492 * context, it shows the object path as <n/a>.
493 */
494void
495acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
496{
497 struct va_format vaf;
498 va_list args;
499 const char *path;
500
501 va_start(args, fmt);
502 vaf.fmt = fmt;
503 vaf.va = &args;
504
505 path = acpi_handle_path(handle);
506 printk("%sACPI: %s: %pV", level, path ? path : "<n/a>" , &vaf);
507
508 va_end(args);
509 kfree(path);
510}
511EXPORT_SYMBOL(acpi_handle_printk);
512
513#if defined(CONFIG_DYNAMIC_DEBUG)
514/**
515 * __acpi_handle_debug: pr_debug with ACPI prefix and object path
516 *
517 * This function is called through acpi_handle_debug macro and debug
518 * prints a message with ACPI prefix and object path. This function
519 * acquires the global namespace mutex to obtain an object path. In
520 * interrupt context, it shows the object path as <n/a>.
521 */
522void
523__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
524 const char *fmt, ...)
525{
526 struct va_format vaf;
527 va_list args;
528 const char *path;
529
530 va_start(args, fmt);
531 vaf.fmt = fmt;
532 vaf.va = &args;
533
534 path = acpi_handle_path(handle);
535 __dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
536
537 va_end(args);
538 kfree(path);
539}
540EXPORT_SYMBOL(__acpi_handle_debug);
541#endif
542
543/**
544 * acpi_has_method: Check whether @handle has a method named @name
545 * @handle: ACPI device handle
546 * @name: name of object or method
547 *
548 * Check whether @handle has a method named @name.
549 */
550bool acpi_has_method(acpi_handle handle, char *name)
551{
552 acpi_handle tmp;
553
554 return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
555}
556EXPORT_SYMBOL(acpi_has_method);
557
558acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
559 u64 arg)
560{
561 union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
562 struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
563
564 obj.integer.value = arg;
565
566 return acpi_evaluate_object(handle, method, &arg_list, NULL);
567}
568EXPORT_SYMBOL(acpi_execute_simple_method);
569
570/**
571 * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
572 * @handle: ACPI device handle
573 *
574 * Evaluate device's _EJ0 method for hotplug operations.
575 */
576acpi_status acpi_evaluate_ej0(acpi_handle handle)
577{
578 acpi_status status;
579
580 status = acpi_execute_simple_method(handle, "_EJ0", 1);
581 if (status == AE_NOT_FOUND)
582 acpi_handle_warn(handle, "No _EJ0 support for device\n");
583 else if (ACPI_FAILURE(status))
584 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
585
586 return status;
587}
588
589/**
590 * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
591 * @handle: ACPI device handle
592 * @lock: lock device if non-zero, otherwise unlock device
593 *
594 * Evaluate device's _LCK method if present to lock/unlock device
595 */
596acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
597{
598 acpi_status status;
599
600 status = acpi_execute_simple_method(handle, "_LCK", !!lock);
601 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
602 if (lock)
603 acpi_handle_warn(handle,
604 "Locking device failed (0x%x)\n", status);
605 else
606 acpi_handle_warn(handle,
607 "Unlocking device failed (0x%x)\n", status);
608 }
609
610 return status;
611}
612
613/**
614 * acpi_evaluate_dsm - evaluate device's _DSM method
615 * @handle: ACPI device handle
616 * @uuid: UUID of requested functions, should be 16 bytes
617 * @rev: revision number of requested function
618 * @func: requested function number
619 * @argv4: the function specific parameter
620 *
621 * Evaluate device's _DSM method with specified UUID, revision id and
622 * function number. Caller needs to free the returned object.
623 *
624 * Though ACPI defines the fourth parameter for _DSM should be a package,
625 * some old BIOSes do expect a buffer or an integer etc.
626 */
627union acpi_object *
628acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
629 union acpi_object *argv4)
630{
631 acpi_status ret;
632 struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
633 union acpi_object params[4];
634 struct acpi_object_list input = {
635 .count = 4,
636 .pointer = params,
637 };
638
639 params[0].type = ACPI_TYPE_BUFFER;
640 params[0].buffer.length = 16;
641 params[0].buffer.pointer = (char *)uuid;
642 params[1].type = ACPI_TYPE_INTEGER;
643 params[1].integer.value = rev;
644 params[2].type = ACPI_TYPE_INTEGER;
645 params[2].integer.value = func;
646 if (argv4) {
647 params[3] = *argv4;
648 } else {
649 params[3].type = ACPI_TYPE_PACKAGE;
650 params[3].package.count = 0;
651 params[3].package.elements = NULL;
652 }
653
654 ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
655 if (ACPI_SUCCESS(ret))
656 return (union acpi_object *)buf.pointer;
657
658 if (ret != AE_NOT_FOUND)
659 acpi_handle_warn(handle,
660 "failed to evaluate _DSM (0x%x)\n", ret);
661
662 return NULL;
663}
664EXPORT_SYMBOL(acpi_evaluate_dsm);
665
666/**
667 * acpi_check_dsm - check if _DSM method supports requested functions.
668 * @handle: ACPI device handle
669 * @uuid: UUID of requested functions, should be 16 bytes at least
670 * @rev: revision number of requested functions
671 * @funcs: bitmap of requested functions
672 *
673 * Evaluate device's _DSM method to check whether it supports requested
674 * functions. Currently only support 64 functions at maximum, should be
675 * enough for now.
676 */
677bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
678{
679 int i;
680 u64 mask = 0;
681 union acpi_object *obj;
682
683 if (funcs == 0)
684 return false;
685
686 obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
687 if (!obj)
688 return false;
689
690 /* For compatibility, old BIOSes may return an integer */
691 if (obj->type == ACPI_TYPE_INTEGER)
692 mask = obj->integer.value;
693 else if (obj->type == ACPI_TYPE_BUFFER)
694 for (i = 0; i < obj->buffer.length && i < 8; i++)
695 mask |= (((u64)obj->buffer.pointer[i]) << (i * 8));
696 ACPI_FREE(obj);
697
698 /*
699 * Bit 0 indicates whether there's support for any functions other than
700 * function 0 for the specified UUID and revision.
701 */
702 if ((mask & 0x1) && (mask & funcs) == funcs)
703 return true;
704
705 return false;
706}
707EXPORT_SYMBOL(acpi_check_dsm);
708
709/**
710 * acpi_dev_present - Detect presence of a given ACPI device in the system.
711 * @hid: Hardware ID of the device.
712 *
713 * Return %true if the device was present at the moment of invocation.
714 * Note that if the device is pluggable, it may since have disappeared.
715 *
716 * For this function to work, acpi_bus_scan() must have been executed
717 * which happens in the subsys_initcall() subsection. Hence, do not
718 * call from a subsys_initcall() or earlier (use acpi_get_devices()
719 * instead). Calling from module_init() is fine (which is synonymous
720 * with device_initcall()).
721 */
722bool acpi_dev_present(const char *hid)
723{
724 struct acpi_device_bus_id *acpi_device_bus_id;
725 bool found = false;
726
727 mutex_lock(&acpi_device_lock);
728 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
729 if (!strcmp(acpi_device_bus_id->bus_id, hid)) {
730 found = true;
731 break;
732 }
733 mutex_unlock(&acpi_device_lock);
734
735 return found;
736}
737EXPORT_SYMBOL(acpi_dev_present);
738
739/*
740 * acpi_backlight= handling, this is done here rather then in video_detect.c
741 * because __setup cannot be used in modules.
742 */
743char acpi_video_backlight_string[16];
744EXPORT_SYMBOL(acpi_video_backlight_string);
745
746static int __init acpi_backlight(char *str)
747{
748 strlcpy(acpi_video_backlight_string, str,
749 sizeof(acpi_video_backlight_string));
750 return 1;
751}
752__setup("acpi_backlight=", acpi_backlight);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 */
8
9#define pr_fmt(fmt) "ACPI: utils: " fmt
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/types.h>
16#include <linux/hardirq.h>
17#include <linux/acpi.h>
18#include <linux/dynamic_debug.h>
19
20#include "internal.h"
21#include "sleep.h"
22
23/* --------------------------------------------------------------------------
24 Object Evaluation Helpers
25 -------------------------------------------------------------------------- */
26static void acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
27{
28 acpi_handle_debug(h, "Evaluate [%s]: %s\n", p, acpi_format_exception(s));
29}
30
31acpi_status
32acpi_extract_package(union acpi_object *package,
33 struct acpi_buffer *format, struct acpi_buffer *buffer)
34{
35 u32 size_required = 0;
36 u32 tail_offset = 0;
37 char *format_string = NULL;
38 u32 format_count = 0;
39 u32 i = 0;
40 u8 *head = NULL;
41 u8 *tail = NULL;
42
43
44 if (!package || (package->type != ACPI_TYPE_PACKAGE)
45 || (package->package.count < 1)) {
46 pr_debug("Invalid package argument\n");
47 return AE_BAD_PARAMETER;
48 }
49
50 if (!format || !format->pointer || (format->length < 1)) {
51 pr_debug("Invalid format argument\n");
52 return AE_BAD_PARAMETER;
53 }
54
55 if (!buffer) {
56 pr_debug("Invalid buffer argument\n");
57 return AE_BAD_PARAMETER;
58 }
59
60 format_count = (format->length / sizeof(char)) - 1;
61 if (format_count > package->package.count) {
62 pr_debug("Format specifies more objects [%d] than present [%d]\n",
63 format_count, package->package.count);
64 return AE_BAD_DATA;
65 }
66
67 format_string = format->pointer;
68
69 /*
70 * Calculate size_required.
71 */
72 for (i = 0; i < format_count; i++) {
73
74 union acpi_object *element = &(package->package.elements[i]);
75
76 switch (element->type) {
77
78 case ACPI_TYPE_INTEGER:
79 switch (format_string[i]) {
80 case 'N':
81 size_required += sizeof(u64);
82 tail_offset += sizeof(u64);
83 break;
84 case 'S':
85 size_required +=
86 sizeof(char *) + sizeof(u64) +
87 sizeof(char);
88 tail_offset += sizeof(char *);
89 break;
90 default:
91 pr_debug("Invalid package element [%d]: got number, expected [%c]\n",
92 i, format_string[i]);
93 return AE_BAD_DATA;
94 }
95 break;
96
97 case ACPI_TYPE_STRING:
98 case ACPI_TYPE_BUFFER:
99 switch (format_string[i]) {
100 case 'S':
101 size_required +=
102 sizeof(char *) +
103 (element->string.length * sizeof(char)) +
104 sizeof(char);
105 tail_offset += sizeof(char *);
106 break;
107 case 'B':
108 size_required +=
109 sizeof(u8 *) + element->buffer.length;
110 tail_offset += sizeof(u8 *);
111 break;
112 default:
113 pr_debug("Invalid package element [%d] got string/buffer, expected [%c]\n",
114 i, format_string[i]);
115 return AE_BAD_DATA;
116 }
117 break;
118 case ACPI_TYPE_LOCAL_REFERENCE:
119 switch (format_string[i]) {
120 case 'R':
121 size_required += sizeof(void *);
122 tail_offset += sizeof(void *);
123 break;
124 default:
125 pr_debug("Invalid package element [%d] got reference, expected [%c]\n",
126 i, format_string[i]);
127 return AE_BAD_DATA;
128 }
129 break;
130
131 case ACPI_TYPE_PACKAGE:
132 default:
133 pr_debug("Unsupported element at index=%d\n", i);
134 /* TBD: handle nested packages... */
135 return AE_SUPPORT;
136 }
137 }
138
139 /*
140 * Validate output buffer.
141 */
142 if (buffer->length == ACPI_ALLOCATE_BUFFER) {
143 buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
144 if (!buffer->pointer)
145 return AE_NO_MEMORY;
146 buffer->length = size_required;
147 } else {
148 if (buffer->length < size_required) {
149 buffer->length = size_required;
150 return AE_BUFFER_OVERFLOW;
151 } else if (buffer->length != size_required ||
152 !buffer->pointer) {
153 return AE_BAD_PARAMETER;
154 }
155 }
156
157 head = buffer->pointer;
158 tail = buffer->pointer + tail_offset;
159
160 /*
161 * Extract package data.
162 */
163 for (i = 0; i < format_count; i++) {
164
165 u8 **pointer = NULL;
166 union acpi_object *element = &(package->package.elements[i]);
167
168 switch (element->type) {
169
170 case ACPI_TYPE_INTEGER:
171 switch (format_string[i]) {
172 case 'N':
173 *((u64 *) head) =
174 element->integer.value;
175 head += sizeof(u64);
176 break;
177 case 'S':
178 pointer = (u8 **) head;
179 *pointer = tail;
180 *((u64 *) tail) =
181 element->integer.value;
182 head += sizeof(u64 *);
183 tail += sizeof(u64);
184 /* NULL terminate string */
185 *tail = (char)0;
186 tail += sizeof(char);
187 break;
188 default:
189 /* Should never get here */
190 break;
191 }
192 break;
193
194 case ACPI_TYPE_STRING:
195 case ACPI_TYPE_BUFFER:
196 switch (format_string[i]) {
197 case 'S':
198 pointer = (u8 **) head;
199 *pointer = tail;
200 memcpy(tail, element->string.pointer,
201 element->string.length);
202 head += sizeof(char *);
203 tail += element->string.length * sizeof(char);
204 /* NULL terminate string */
205 *tail = (char)0;
206 tail += sizeof(char);
207 break;
208 case 'B':
209 pointer = (u8 **) head;
210 *pointer = tail;
211 memcpy(tail, element->buffer.pointer,
212 element->buffer.length);
213 head += sizeof(u8 *);
214 tail += element->buffer.length;
215 break;
216 default:
217 /* Should never get here */
218 break;
219 }
220 break;
221 case ACPI_TYPE_LOCAL_REFERENCE:
222 switch (format_string[i]) {
223 case 'R':
224 *(void **)head =
225 (void *)element->reference.handle;
226 head += sizeof(void *);
227 break;
228 default:
229 /* Should never get here */
230 break;
231 }
232 break;
233 case ACPI_TYPE_PACKAGE:
234 /* TBD: handle nested packages... */
235 default:
236 /* Should never get here */
237 break;
238 }
239 }
240
241 return AE_OK;
242}
243
244EXPORT_SYMBOL(acpi_extract_package);
245
246acpi_status
247acpi_evaluate_integer(acpi_handle handle,
248 acpi_string pathname,
249 struct acpi_object_list *arguments, unsigned long long *data)
250{
251 acpi_status status = AE_OK;
252 union acpi_object element;
253 struct acpi_buffer buffer = { 0, NULL };
254
255 if (!data)
256 return AE_BAD_PARAMETER;
257
258 buffer.length = sizeof(union acpi_object);
259 buffer.pointer = &element;
260 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
261 if (ACPI_FAILURE(status)) {
262 acpi_util_eval_error(handle, pathname, status);
263 return status;
264 }
265
266 if (element.type != ACPI_TYPE_INTEGER) {
267 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
268 return AE_BAD_DATA;
269 }
270
271 *data = element.integer.value;
272
273 acpi_handle_debug(handle, "Return value [%llu]\n", *data);
274
275 return AE_OK;
276}
277
278EXPORT_SYMBOL(acpi_evaluate_integer);
279
280int acpi_get_local_address(acpi_handle handle, u32 *addr)
281{
282 unsigned long long adr;
283 acpi_status status;
284
285 status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &adr);
286 if (ACPI_FAILURE(status))
287 return -ENODATA;
288
289 *addr = (u32)adr;
290 return 0;
291}
292EXPORT_SYMBOL(acpi_get_local_address);
293
294#define ACPI_MAX_SUB_BUF_SIZE 9
295
296const char *acpi_get_subsystem_id(acpi_handle handle)
297{
298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
299 union acpi_object *obj;
300 acpi_status status;
301 const char *sub;
302 size_t len;
303
304 status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
305 if (ACPI_FAILURE(status)) {
306 acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
307 return ERR_PTR(-ENODATA);
308 }
309
310 obj = buffer.pointer;
311 if (obj->type == ACPI_TYPE_STRING) {
312 len = strlen(obj->string.pointer);
313 if (len < ACPI_MAX_SUB_BUF_SIZE && len > 0) {
314 sub = kstrdup(obj->string.pointer, GFP_KERNEL);
315 if (!sub)
316 sub = ERR_PTR(-ENOMEM);
317 } else {
318 acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n", len);
319 sub = ERR_PTR(-ENODATA);
320 }
321 } else {
322 acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
323 sub = ERR_PTR(-ENODATA);
324 }
325
326 acpi_os_free(buffer.pointer);
327
328 return sub;
329}
330EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
331
332bool acpi_evaluate_reference(acpi_handle handle, acpi_string pathname,
333 struct acpi_object_list *arguments,
334 struct acpi_handle_list *list)
335{
336 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
337 union acpi_object *package;
338 acpi_status status;
339 bool ret = false;
340 u32 i;
341
342 if (!list)
343 return false;
344
345 /* Evaluate object. */
346
347 status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
348 if (ACPI_FAILURE(status))
349 goto end;
350
351 package = buffer.pointer;
352
353 if (buffer.length == 0 || !package ||
354 package->type != ACPI_TYPE_PACKAGE || !package->package.count)
355 goto err;
356
357 list->count = package->package.count;
358 list->handles = kcalloc(list->count, sizeof(*list->handles), GFP_KERNEL);
359 if (!list->handles)
360 goto err_clear;
361
362 /* Extract package data. */
363
364 for (i = 0; i < list->count; i++) {
365 union acpi_object *element = &(package->package.elements[i]);
366
367 if (element->type != ACPI_TYPE_LOCAL_REFERENCE ||
368 !element->reference.handle)
369 goto err_free;
370
371 /* Get the acpi_handle. */
372
373 list->handles[i] = element->reference.handle;
374 acpi_handle_debug(list->handles[i], "Found in reference list\n");
375 }
376
377 ret = true;
378
379end:
380 kfree(buffer.pointer);
381
382 return ret;
383
384err_free:
385 kfree(list->handles);
386 list->handles = NULL;
387
388err_clear:
389 list->count = 0;
390
391err:
392 acpi_util_eval_error(handle, pathname, status);
393 goto end;
394}
395
396EXPORT_SYMBOL(acpi_evaluate_reference);
397
398/**
399 * acpi_handle_list_equal - Check if two ACPI handle lists are the same
400 * @list1: First list to compare.
401 * @list2: Second list to compare.
402 *
403 * Return true if the given ACPI handle lists are of the same size and
404 * contain the same ACPI handles in the same order. Otherwise, return false.
405 */
406bool acpi_handle_list_equal(struct acpi_handle_list *list1,
407 struct acpi_handle_list *list2)
408{
409 return list1->count == list2->count &&
410 !memcmp(list1->handles, list2->handles,
411 list1->count * sizeof(*list1->handles));
412}
413EXPORT_SYMBOL_GPL(acpi_handle_list_equal);
414
415/**
416 * acpi_handle_list_replace - Replace one ACPI handle list with another
417 * @dst: ACPI handle list to replace.
418 * @src: Source ACPI handle list.
419 *
420 * Free the handles table in @dst, move the handles table from @src to @dst,
421 * copy count from @src to @dst and clear @src.
422 */
423void acpi_handle_list_replace(struct acpi_handle_list *dst,
424 struct acpi_handle_list *src)
425{
426 if (dst->count)
427 kfree(dst->handles);
428
429 dst->count = src->count;
430 dst->handles = src->handles;
431
432 src->handles = NULL;
433 src->count = 0;
434}
435EXPORT_SYMBOL_GPL(acpi_handle_list_replace);
436
437/**
438 * acpi_handle_list_free - Free the handles table in an ACPI handle list
439 * @list: ACPI handle list to free.
440 *
441 * Free the handles table in @list and clear its count field.
442 */
443void acpi_handle_list_free(struct acpi_handle_list *list)
444{
445 if (!list->count)
446 return;
447
448 kfree(list->handles);
449 list->count = 0;
450}
451EXPORT_SYMBOL_GPL(acpi_handle_list_free);
452
453/**
454 * acpi_device_dep - Check ACPI device dependency
455 * @target: ACPI handle of the target ACPI device.
456 * @match: ACPI handle to look up in the target's _DEP list.
457 *
458 * Return true if @match is present in the list returned by _DEP for
459 * @target or false otherwise.
460 */
461bool acpi_device_dep(acpi_handle target, acpi_handle match)
462{
463 struct acpi_handle_list dep_devices;
464 bool ret = false;
465 int i;
466
467 if (!acpi_has_method(target, "_DEP"))
468 return false;
469
470 if (!acpi_evaluate_reference(target, "_DEP", NULL, &dep_devices)) {
471 acpi_handle_debug(target, "Failed to evaluate _DEP.\n");
472 return false;
473 }
474
475 for (i = 0; i < dep_devices.count; i++) {
476 if (dep_devices.handles[i] == match) {
477 ret = true;
478 break;
479 }
480 }
481
482 acpi_handle_list_free(&dep_devices);
483 return ret;
484}
485EXPORT_SYMBOL_GPL(acpi_device_dep);
486
487acpi_status
488acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
489{
490 acpi_status status;
491 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
492 union acpi_object *output;
493
494 status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
495
496 if (ACPI_FAILURE(status))
497 return status;
498
499 output = buffer.pointer;
500
501 if (!output || output->type != ACPI_TYPE_PACKAGE
502 || !output->package.count
503 || output->package.elements[0].type != ACPI_TYPE_BUFFER
504 || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
505 status = AE_TYPE;
506 goto out;
507 }
508
509 status = acpi_decode_pld_buffer(
510 output->package.elements[0].buffer.pointer,
511 output->package.elements[0].buffer.length,
512 pld);
513
514out:
515 kfree(buffer.pointer);
516 return status;
517}
518EXPORT_SYMBOL(acpi_get_physical_device_location);
519
520/**
521 * acpi_evaluate_ost: Evaluate _OST for hotplug operations
522 * @handle: ACPI device handle
523 * @source_event: source event code
524 * @status_code: status code
525 * @status_buf: optional detailed information (NULL if none)
526 *
527 * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
528 * must call this function when evaluating _OST for hotplug operations.
529 * When the platform does not support _OST, this function has no effect.
530 */
531acpi_status
532acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
533 struct acpi_buffer *status_buf)
534{
535 union acpi_object params[3] = {
536 {.type = ACPI_TYPE_INTEGER,},
537 {.type = ACPI_TYPE_INTEGER,},
538 {.type = ACPI_TYPE_BUFFER,}
539 };
540 struct acpi_object_list arg_list = {3, params};
541
542 params[0].integer.value = source_event;
543 params[1].integer.value = status_code;
544 if (status_buf != NULL) {
545 params[2].buffer.pointer = status_buf->pointer;
546 params[2].buffer.length = status_buf->length;
547 } else {
548 params[2].buffer.pointer = NULL;
549 params[2].buffer.length = 0;
550 }
551
552 return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
553}
554EXPORT_SYMBOL(acpi_evaluate_ost);
555
556/**
557 * acpi_handle_path: Return the object path of handle
558 * @handle: ACPI device handle
559 *
560 * Caller must free the returned buffer
561 */
562char *acpi_handle_path(acpi_handle handle)
563{
564 struct acpi_buffer buffer = {
565 .length = ACPI_ALLOCATE_BUFFER,
566 .pointer = NULL
567 };
568
569 if (in_interrupt() ||
570 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
571 return NULL;
572 return buffer.pointer;
573}
574
575/**
576 * acpi_handle_printk: Print message with ACPI prefix and object path
577 * @level: log level
578 * @handle: ACPI device handle
579 * @fmt: format string
580 *
581 * This function is called through acpi_handle_<level> macros and prints
582 * a message with ACPI prefix and object path. This function acquires
583 * the global namespace mutex to obtain an object path. In interrupt
584 * context, it shows the object path as <n/a>.
585 */
586void
587acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
588{
589 struct va_format vaf;
590 va_list args;
591 const char *path;
592
593 va_start(args, fmt);
594 vaf.fmt = fmt;
595 vaf.va = &args;
596
597 path = acpi_handle_path(handle);
598 printk("%sACPI: %s: %pV", level, path ? path : "<n/a>", &vaf);
599
600 va_end(args);
601 kfree(path);
602}
603EXPORT_SYMBOL(acpi_handle_printk);
604
605#if defined(CONFIG_DYNAMIC_DEBUG)
606/**
607 * __acpi_handle_debug: pr_debug with ACPI prefix and object path
608 * @descriptor: Dynamic Debug descriptor
609 * @handle: ACPI device handle
610 * @fmt: format string
611 *
612 * This function is called through acpi_handle_debug macro and debug
613 * prints a message with ACPI prefix and object path. This function
614 * acquires the global namespace mutex to obtain an object path. In
615 * interrupt context, it shows the object path as <n/a>.
616 */
617void
618__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
619 const char *fmt, ...)
620{
621 struct va_format vaf;
622 va_list args;
623 const char *path;
624
625 va_start(args, fmt);
626 vaf.fmt = fmt;
627 vaf.va = &args;
628
629 path = acpi_handle_path(handle);
630 __dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
631
632 va_end(args);
633 kfree(path);
634}
635EXPORT_SYMBOL(__acpi_handle_debug);
636#endif
637
638/**
639 * acpi_evaluation_failure_warn - Log evaluation failure warning.
640 * @handle: Parent object handle.
641 * @name: Name of the object whose evaluation has failed.
642 * @status: Status value returned by the failing object evaluation.
643 */
644void acpi_evaluation_failure_warn(acpi_handle handle, const char *name,
645 acpi_status status)
646{
647 acpi_handle_warn(handle, "%s evaluation failed: %s\n", name,
648 acpi_format_exception(status));
649}
650EXPORT_SYMBOL_GPL(acpi_evaluation_failure_warn);
651
652/**
653 * acpi_has_method: Check whether @handle has a method named @name
654 * @handle: ACPI device handle
655 * @name: name of object or method
656 *
657 * Check whether @handle has a method named @name.
658 */
659bool acpi_has_method(acpi_handle handle, char *name)
660{
661 acpi_handle tmp;
662
663 return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
664}
665EXPORT_SYMBOL(acpi_has_method);
666
667acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
668 u64 arg)
669{
670 union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
671 struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
672
673 obj.integer.value = arg;
674
675 return acpi_evaluate_object(handle, method, &arg_list, NULL);
676}
677EXPORT_SYMBOL(acpi_execute_simple_method);
678
679/**
680 * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
681 * @handle: ACPI device handle
682 *
683 * Evaluate device's _EJ0 method for hotplug operations.
684 */
685acpi_status acpi_evaluate_ej0(acpi_handle handle)
686{
687 acpi_status status;
688
689 status = acpi_execute_simple_method(handle, "_EJ0", 1);
690 if (status == AE_NOT_FOUND)
691 acpi_handle_warn(handle, "No _EJ0 support for device\n");
692 else if (ACPI_FAILURE(status))
693 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
694
695 return status;
696}
697
698/**
699 * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
700 * @handle: ACPI device handle
701 * @lock: lock device if non-zero, otherwise unlock device
702 *
703 * Evaluate device's _LCK method if present to lock/unlock device
704 */
705acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
706{
707 acpi_status status;
708
709 status = acpi_execute_simple_method(handle, "_LCK", !!lock);
710 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
711 if (lock)
712 acpi_handle_warn(handle,
713 "Locking device failed (0x%x)\n", status);
714 else
715 acpi_handle_warn(handle,
716 "Unlocking device failed (0x%x)\n", status);
717 }
718
719 return status;
720}
721
722/**
723 * acpi_evaluate_reg: Evaluate _REG method to register OpRegion presence
724 * @handle: ACPI device handle
725 * @space_id: ACPI address space id to register OpRegion presence for
726 * @function: Parameter to pass to _REG one of ACPI_REG_CONNECT or
727 * ACPI_REG_DISCONNECT
728 *
729 * Evaluate device's _REG method to register OpRegion presence.
730 */
731acpi_status acpi_evaluate_reg(acpi_handle handle, u8 space_id, u32 function)
732{
733 struct acpi_object_list arg_list;
734 union acpi_object params[2];
735
736 params[0].type = ACPI_TYPE_INTEGER;
737 params[0].integer.value = space_id;
738 params[1].type = ACPI_TYPE_INTEGER;
739 params[1].integer.value = function;
740 arg_list.count = 2;
741 arg_list.pointer = params;
742
743 return acpi_evaluate_object(handle, "_REG", &arg_list, NULL);
744}
745EXPORT_SYMBOL(acpi_evaluate_reg);
746
747/**
748 * acpi_evaluate_dsm - evaluate device's _DSM method
749 * @handle: ACPI device handle
750 * @guid: GUID of requested functions, should be 16 bytes
751 * @rev: revision number of requested function
752 * @func: requested function number
753 * @argv4: the function specific parameter
754 *
755 * Evaluate device's _DSM method with specified GUID, revision id and
756 * function number. Caller needs to free the returned object.
757 *
758 * Though ACPI defines the fourth parameter for _DSM should be a package,
759 * some old BIOSes do expect a buffer or an integer etc.
760 */
761union acpi_object *
762acpi_evaluate_dsm(acpi_handle handle, const guid_t *guid, u64 rev, u64 func,
763 union acpi_object *argv4)
764{
765 acpi_status ret;
766 struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
767 union acpi_object params[4];
768 struct acpi_object_list input = {
769 .count = 4,
770 .pointer = params,
771 };
772
773 params[0].type = ACPI_TYPE_BUFFER;
774 params[0].buffer.length = 16;
775 params[0].buffer.pointer = (u8 *)guid;
776 params[1].type = ACPI_TYPE_INTEGER;
777 params[1].integer.value = rev;
778 params[2].type = ACPI_TYPE_INTEGER;
779 params[2].integer.value = func;
780 if (argv4) {
781 params[3] = *argv4;
782 } else {
783 params[3].type = ACPI_TYPE_PACKAGE;
784 params[3].package.count = 0;
785 params[3].package.elements = NULL;
786 }
787
788 ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
789 if (ACPI_SUCCESS(ret))
790 return (union acpi_object *)buf.pointer;
791
792 if (ret != AE_NOT_FOUND)
793 acpi_handle_warn(handle,
794 "failed to evaluate _DSM %pUb (0x%x)\n", guid, ret);
795
796 return NULL;
797}
798EXPORT_SYMBOL(acpi_evaluate_dsm);
799
800/**
801 * acpi_check_dsm - check if _DSM method supports requested functions.
802 * @handle: ACPI device handle
803 * @guid: GUID of requested functions, should be 16 bytes at least
804 * @rev: revision number of requested functions
805 * @funcs: bitmap of requested functions
806 *
807 * Evaluate device's _DSM method to check whether it supports requested
808 * functions. Currently only support 64 functions at maximum, should be
809 * enough for now.
810 */
811bool acpi_check_dsm(acpi_handle handle, const guid_t *guid, u64 rev, u64 funcs)
812{
813 int i;
814 u64 mask = 0;
815 union acpi_object *obj;
816
817 if (funcs == 0)
818 return false;
819
820 obj = acpi_evaluate_dsm(handle, guid, rev, 0, NULL);
821 if (!obj)
822 return false;
823
824 /* For compatibility, old BIOSes may return an integer */
825 if (obj->type == ACPI_TYPE_INTEGER)
826 mask = obj->integer.value;
827 else if (obj->type == ACPI_TYPE_BUFFER)
828 for (i = 0; i < obj->buffer.length && i < 8; i++)
829 mask |= (((u64)obj->buffer.pointer[i]) << (i * 8));
830 ACPI_FREE(obj);
831
832 /*
833 * Bit 0 indicates whether there's support for any functions other than
834 * function 0 for the specified GUID and revision.
835 */
836 if ((mask & 0x1) && (mask & funcs) == funcs)
837 return true;
838
839 return false;
840}
841EXPORT_SYMBOL(acpi_check_dsm);
842
843/**
844 * acpi_dev_uid_to_integer - treat ACPI device _UID as integer
845 * @adev: ACPI device to get _UID from
846 * @integer: output buffer for integer
847 *
848 * Considers _UID as integer and converts it to @integer.
849 *
850 * Returns 0 on success, or negative error code otherwise.
851 */
852int acpi_dev_uid_to_integer(struct acpi_device *adev, u64 *integer)
853{
854 const char *uid;
855
856 if (!adev)
857 return -ENODEV;
858
859 uid = acpi_device_uid(adev);
860 if (!uid)
861 return -ENODATA;
862
863 return kstrtou64(uid, 0, integer);
864}
865EXPORT_SYMBOL(acpi_dev_uid_to_integer);
866
867/**
868 * acpi_dev_found - Detect presence of a given ACPI device in the namespace.
869 * @hid: Hardware ID of the device.
870 *
871 * Return %true if the device was present at the moment of invocation.
872 * Note that if the device is pluggable, it may since have disappeared.
873 *
874 * For this function to work, acpi_bus_scan() must have been executed
875 * which happens in the subsys_initcall() subsection. Hence, do not
876 * call from a subsys_initcall() or earlier (use acpi_get_devices()
877 * instead). Calling from module_init() is fine (which is synonymous
878 * with device_initcall()).
879 */
880bool acpi_dev_found(const char *hid)
881{
882 struct acpi_device_bus_id *acpi_device_bus_id;
883 bool found = false;
884
885 mutex_lock(&acpi_device_lock);
886 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
887 if (!strcmp(acpi_device_bus_id->bus_id, hid)) {
888 found = true;
889 break;
890 }
891 mutex_unlock(&acpi_device_lock);
892
893 return found;
894}
895EXPORT_SYMBOL(acpi_dev_found);
896
897struct acpi_dev_match_info {
898 struct acpi_device_id hid[2];
899 const char *uid;
900 s64 hrv;
901};
902
903static int acpi_dev_match_cb(struct device *dev, const void *data)
904{
905 struct acpi_device *adev = to_acpi_device(dev);
906 const struct acpi_dev_match_info *match = data;
907 unsigned long long hrv;
908 acpi_status status;
909
910 if (acpi_match_device_ids(adev, match->hid))
911 return 0;
912
913 if (match->uid && !acpi_dev_uid_match(adev, match->uid))
914 return 0;
915
916 if (match->hrv == -1)
917 return 1;
918
919 status = acpi_evaluate_integer(adev->handle, "_HRV", NULL, &hrv);
920 if (ACPI_FAILURE(status))
921 return 0;
922
923 return hrv == match->hrv;
924}
925
926/**
927 * acpi_dev_present - Detect that a given ACPI device is present
928 * @hid: Hardware ID of the device.
929 * @uid: Unique ID of the device, pass NULL to not check _UID
930 * @hrv: Hardware Revision of the device, pass -1 to not check _HRV
931 *
932 * Return %true if a matching device was present at the moment of invocation.
933 * Note that if the device is pluggable, it may since have disappeared.
934 *
935 * Note that unlike acpi_dev_found() this function checks the status
936 * of the device. So for devices which are present in the DSDT, but
937 * which are disabled (their _STA callback returns 0) this function
938 * will return false.
939 *
940 * For this function to work, acpi_bus_scan() must have been executed
941 * which happens in the subsys_initcall() subsection. Hence, do not
942 * call from a subsys_initcall() or earlier (use acpi_get_devices()
943 * instead). Calling from module_init() is fine (which is synonymous
944 * with device_initcall()).
945 */
946bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
947{
948 struct acpi_dev_match_info match = {};
949 struct device *dev;
950
951 strscpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
952 match.uid = uid;
953 match.hrv = hrv;
954
955 dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
956 put_device(dev);
957 return !!dev;
958}
959EXPORT_SYMBOL(acpi_dev_present);
960
961/**
962 * acpi_dev_get_next_match_dev - Return the next match of ACPI device
963 * @adev: Pointer to the previous ACPI device matching this @hid, @uid and @hrv
964 * @hid: Hardware ID of the device.
965 * @uid: Unique ID of the device, pass NULL to not check _UID
966 * @hrv: Hardware Revision of the device, pass -1 to not check _HRV
967 *
968 * Return the next match of ACPI device if another matching device was present
969 * at the moment of invocation, or NULL otherwise.
970 *
971 * The caller is responsible for invoking acpi_dev_put() on the returned device.
972 * On the other hand the function invokes acpi_dev_put() on the given @adev
973 * assuming that its reference counter had been increased beforehand.
974 *
975 * See additional information in acpi_dev_present() as well.
976 */
977struct acpi_device *
978acpi_dev_get_next_match_dev(struct acpi_device *adev, const char *hid, const char *uid, s64 hrv)
979{
980 struct device *start = adev ? &adev->dev : NULL;
981 struct acpi_dev_match_info match = {};
982 struct device *dev;
983
984 strscpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
985 match.uid = uid;
986 match.hrv = hrv;
987
988 dev = bus_find_device(&acpi_bus_type, start, &match, acpi_dev_match_cb);
989 acpi_dev_put(adev);
990 return dev ? to_acpi_device(dev) : NULL;
991}
992EXPORT_SYMBOL(acpi_dev_get_next_match_dev);
993
994/**
995 * acpi_dev_get_first_match_dev - Return the first match of ACPI device
996 * @hid: Hardware ID of the device.
997 * @uid: Unique ID of the device, pass NULL to not check _UID
998 * @hrv: Hardware Revision of the device, pass -1 to not check _HRV
999 *
1000 * Return the first match of ACPI device if a matching device was present
1001 * at the moment of invocation, or NULL otherwise.
1002 *
1003 * The caller is responsible for invoking acpi_dev_put() on the returned device.
1004 *
1005 * See additional information in acpi_dev_present() as well.
1006 */
1007struct acpi_device *
1008acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
1009{
1010 return acpi_dev_get_next_match_dev(NULL, hid, uid, hrv);
1011}
1012EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
1013
1014/**
1015 * acpi_reduced_hardware - Return if this is an ACPI-reduced-hw machine
1016 *
1017 * Return true when running on an ACPI-reduced-hw machine, false otherwise.
1018 */
1019bool acpi_reduced_hardware(void)
1020{
1021 return acpi_gbl_reduced_hardware;
1022}
1023EXPORT_SYMBOL_GPL(acpi_reduced_hardware);
1024
1025/*
1026 * acpi_backlight= handling, this is done here rather then in video_detect.c
1027 * because __setup cannot be used in modules.
1028 */
1029char acpi_video_backlight_string[16];
1030EXPORT_SYMBOL(acpi_video_backlight_string);
1031
1032static int __init acpi_backlight(char *str)
1033{
1034 strscpy(acpi_video_backlight_string, str,
1035 sizeof(acpi_video_backlight_string));
1036 return 1;
1037}
1038__setup("acpi_backlight=", acpi_backlight);
1039
1040/**
1041 * acpi_match_platform_list - Check if the system matches with a given list
1042 * @plat: pointer to acpi_platform_list table terminated by a NULL entry
1043 *
1044 * Return the matched index if the system is found in the platform list.
1045 * Otherwise, return a negative error code.
1046 */
1047int acpi_match_platform_list(const struct acpi_platform_list *plat)
1048{
1049 struct acpi_table_header hdr;
1050 int idx = 0;
1051
1052 if (acpi_disabled)
1053 return -ENODEV;
1054
1055 for (; plat->oem_id[0]; plat++, idx++) {
1056 if (ACPI_FAILURE(acpi_get_table_header(plat->table, 0, &hdr)))
1057 continue;
1058
1059 if (strncmp(plat->oem_id, hdr.oem_id, ACPI_OEM_ID_SIZE))
1060 continue;
1061
1062 if (strncmp(plat->oem_table_id, hdr.oem_table_id, ACPI_OEM_TABLE_ID_SIZE))
1063 continue;
1064
1065 if ((plat->pred == all_versions) ||
1066 (plat->pred == less_than_or_equal && hdr.oem_revision <= plat->oem_revision) ||
1067 (plat->pred == greater_than_or_equal && hdr.oem_revision >= plat->oem_revision) ||
1068 (plat->pred == equal && hdr.oem_revision == plat->oem_revision))
1069 return idx;
1070 }
1071
1072 return -ENODEV;
1073}
1074EXPORT_SYMBOL(acpi_match_platform_list);