GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / acpi / utils.c
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
34 ACPI_MODULE_NAME("utils");
35
36 /* --------------------------------------------------------------------------
37                             Object Evaluation Helpers
38    -------------------------------------------------------------------------- */
39 static void
40 acpi_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
53 acpi_status
54 acpi_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
283 EXPORT_SYMBOL(acpi_extract_package);
284
285 acpi_status
286 acpi_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
317 EXPORT_SYMBOL(acpi_evaluate_integer);
318
319 acpi_status
320 acpi_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
400 EXPORT_SYMBOL(acpi_evaluate_reference);
401
402 acpi_status
403 acpi_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
429 out:
430         kfree(buffer.pointer);
431         return status;
432 }
433 EXPORT_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  */
446 acpi_status
447 acpi_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 }
469 EXPORT_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  */
476 static 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  */
497 void
498 acpi_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 }
514 EXPORT_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  */
525 void
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 }
543 EXPORT_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  */
553 bool 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 }
559 EXPORT_SYMBOL(acpi_has_method);
560
561 acpi_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 }
571 EXPORT_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  */
579 acpi_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  */
599 acpi_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  */
630 union acpi_object *
631 acpi_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 }
667 EXPORT_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  */
680 bool 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 }
710 EXPORT_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  */
716 char acpi_video_backlight_string[16];
717 EXPORT_SYMBOL(acpi_video_backlight_string);
718
719 static 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);