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1/*
2 * ACPI-WMI mapping driver
3 *
4 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
5 *
6 * GUID parsing code from ldm.c is:
7 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
8 * Copyright (c) 2001-2007 Anton Altaparmakov
9 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
10 *
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 *
27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 */
29
30#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
32#include <linux/kernel.h>
33#include <linux/init.h>
34#include <linux/types.h>
35#include <linux/device.h>
36#include <linux/list.h>
37#include <linux/acpi.h>
38#include <linux/slab.h>
39#include <linux/module.h>
40
41ACPI_MODULE_NAME("wmi");
42MODULE_AUTHOR("Carlos Corbacho");
43MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
44MODULE_LICENSE("GPL");
45
46#define ACPI_WMI_CLASS "wmi"
47
48static LIST_HEAD(wmi_block_list);
49
50struct guid_block {
51 char guid[16];
52 union {
53 char object_id[2];
54 struct {
55 unsigned char notify_id;
56 unsigned char reserved;
57 };
58 };
59 u8 instance_count;
60 u8 flags;
61};
62
63struct wmi_block {
64 struct list_head list;
65 struct guid_block gblock;
66 acpi_handle handle;
67 wmi_notify_handler handler;
68 void *handler_data;
69 struct device dev;
70};
71
72
73/*
74 * If the GUID data block is marked as expensive, we must enable and
75 * explicitily disable data collection.
76 */
77#define ACPI_WMI_EXPENSIVE 0x1
78#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
79#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
80#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
81
82static bool debug_event;
83module_param(debug_event, bool, 0444);
84MODULE_PARM_DESC(debug_event,
85 "Log WMI Events [0/1]");
86
87static bool debug_dump_wdg;
88module_param(debug_dump_wdg, bool, 0444);
89MODULE_PARM_DESC(debug_dump_wdg,
90 "Dump available WMI interfaces [0/1]");
91
92static int acpi_wmi_remove(struct acpi_device *device);
93static int acpi_wmi_add(struct acpi_device *device);
94static void acpi_wmi_notify(struct acpi_device *device, u32 event);
95
96static const struct acpi_device_id wmi_device_ids[] = {
97 {"PNP0C14", 0},
98 {"pnp0c14", 0},
99 {"", 0},
100};
101MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
102
103static struct acpi_driver acpi_wmi_driver = {
104 .name = "wmi",
105 .class = ACPI_WMI_CLASS,
106 .ids = wmi_device_ids,
107 .ops = {
108 .add = acpi_wmi_add,
109 .remove = acpi_wmi_remove,
110 .notify = acpi_wmi_notify,
111 },
112};
113
114/*
115 * GUID parsing functions
116 */
117
118/**
119 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
120 * @src: Pointer to at least 2 characters to convert.
121 *
122 * Convert a two character ASCII hex string to a number.
123 *
124 * Return: 0-255 Success, the byte was parsed correctly
125 * -1 Error, an invalid character was supplied
126 */
127static int wmi_parse_hexbyte(const u8 *src)
128{
129 int h;
130 int value;
131
132 /* high part */
133 h = value = hex_to_bin(src[0]);
134 if (value < 0)
135 return -1;
136
137 /* low part */
138 value = hex_to_bin(src[1]);
139 if (value >= 0)
140 return (h << 4) | value;
141 return -1;
142}
143
144/**
145 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
146 * @src: Memory block holding binary GUID (16 bytes)
147 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
148 *
149 * Byte swap a binary GUID to match it's real GUID value
150 */
151static void wmi_swap_bytes(u8 *src, u8 *dest)
152{
153 int i;
154
155 for (i = 0; i <= 3; i++)
156 memcpy(dest + i, src + (3 - i), 1);
157
158 for (i = 0; i <= 1; i++)
159 memcpy(dest + 4 + i, src + (5 - i), 1);
160
161 for (i = 0; i <= 1; i++)
162 memcpy(dest + 6 + i, src + (7 - i), 1);
163
164 memcpy(dest + 8, src + 8, 8);
165}
166
167/**
168 * wmi_parse_guid - Convert GUID from ASCII to binary
169 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
170 * @dest: Memory block to hold binary GUID (16 bytes)
171 *
172 * N.B. The GUID need not be NULL terminated.
173 *
174 * Return: 'true' @dest contains binary GUID
175 * 'false' @dest contents are undefined
176 */
177static bool wmi_parse_guid(const u8 *src, u8 *dest)
178{
179 static const int size[] = { 4, 2, 2, 2, 6 };
180 int i, j, v;
181
182 if (src[8] != '-' || src[13] != '-' ||
183 src[18] != '-' || src[23] != '-')
184 return false;
185
186 for (j = 0; j < 5; j++, src++) {
187 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
188 v = wmi_parse_hexbyte(src);
189 if (v < 0)
190 return false;
191 }
192 }
193
194 return true;
195}
196
197static bool find_guid(const char *guid_string, struct wmi_block **out)
198{
199 char tmp[16], guid_input[16];
200 struct wmi_block *wblock;
201 struct guid_block *block;
202 struct list_head *p;
203
204 wmi_parse_guid(guid_string, tmp);
205 wmi_swap_bytes(tmp, guid_input);
206
207 list_for_each(p, &wmi_block_list) {
208 wblock = list_entry(p, struct wmi_block, list);
209 block = &wblock->gblock;
210
211 if (memcmp(block->guid, guid_input, 16) == 0) {
212 if (out)
213 *out = wblock;
214 return true;
215 }
216 }
217 return false;
218}
219
220static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
221{
222 struct guid_block *block = NULL;
223 char method[5];
224 acpi_status status;
225 acpi_handle handle;
226
227 block = &wblock->gblock;
228 handle = wblock->handle;
229
230 snprintf(method, 5, "WE%02X", block->notify_id);
231 status = acpi_execute_simple_method(handle, method, enable);
232
233 if (status != AE_OK && status != AE_NOT_FOUND)
234 return status;
235 else
236 return AE_OK;
237}
238
239/*
240 * Exported WMI functions
241 */
242/**
243 * wmi_evaluate_method - Evaluate a WMI method
244 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
245 * @instance: Instance index
246 * @method_id: Method ID to call
247 * &in: Buffer containing input for the method call
248 * &out: Empty buffer to return the method results
249 *
250 * Call an ACPI-WMI method
251 */
252acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
253u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
254{
255 struct guid_block *block = NULL;
256 struct wmi_block *wblock = NULL;
257 acpi_handle handle;
258 acpi_status status;
259 struct acpi_object_list input;
260 union acpi_object params[3];
261 char method[5] = "WM";
262
263 if (!find_guid(guid_string, &wblock))
264 return AE_ERROR;
265
266 block = &wblock->gblock;
267 handle = wblock->handle;
268
269 if (!(block->flags & ACPI_WMI_METHOD))
270 return AE_BAD_DATA;
271
272 if (block->instance_count < instance)
273 return AE_BAD_PARAMETER;
274
275 input.count = 2;
276 input.pointer = params;
277 params[0].type = ACPI_TYPE_INTEGER;
278 params[0].integer.value = instance;
279 params[1].type = ACPI_TYPE_INTEGER;
280 params[1].integer.value = method_id;
281
282 if (in) {
283 input.count = 3;
284
285 if (block->flags & ACPI_WMI_STRING) {
286 params[2].type = ACPI_TYPE_STRING;
287 } else {
288 params[2].type = ACPI_TYPE_BUFFER;
289 }
290 params[2].buffer.length = in->length;
291 params[2].buffer.pointer = in->pointer;
292 }
293
294 strncat(method, block->object_id, 2);
295
296 status = acpi_evaluate_object(handle, method, &input, out);
297
298 return status;
299}
300EXPORT_SYMBOL_GPL(wmi_evaluate_method);
301
302/**
303 * wmi_query_block - Return contents of a WMI block
304 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
305 * @instance: Instance index
306 * &out: Empty buffer to return the contents of the data block to
307 *
308 * Return the contents of an ACPI-WMI data block to a buffer
309 */
310acpi_status wmi_query_block(const char *guid_string, u8 instance,
311struct acpi_buffer *out)
312{
313 struct guid_block *block = NULL;
314 struct wmi_block *wblock = NULL;
315 acpi_handle handle;
316 acpi_status status, wc_status = AE_ERROR;
317 struct acpi_object_list input;
318 union acpi_object wq_params[1];
319 char method[5];
320 char wc_method[5] = "WC";
321
322 if (!guid_string || !out)
323 return AE_BAD_PARAMETER;
324
325 if (!find_guid(guid_string, &wblock))
326 return AE_ERROR;
327
328 block = &wblock->gblock;
329 handle = wblock->handle;
330
331 if (block->instance_count < instance)
332 return AE_BAD_PARAMETER;
333
334 /* Check GUID is a data block */
335 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
336 return AE_ERROR;
337
338 input.count = 1;
339 input.pointer = wq_params;
340 wq_params[0].type = ACPI_TYPE_INTEGER;
341 wq_params[0].integer.value = instance;
342
343 /*
344 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
345 * enable collection.
346 */
347 if (block->flags & ACPI_WMI_EXPENSIVE) {
348 strncat(wc_method, block->object_id, 2);
349
350 /*
351 * Some GUIDs break the specification by declaring themselves
352 * expensive, but have no corresponding WCxx method. So we
353 * should not fail if this happens.
354 */
355 if (acpi_has_method(handle, wc_method))
356 wc_status = acpi_execute_simple_method(handle,
357 wc_method, 1);
358 }
359
360 strcpy(method, "WQ");
361 strncat(method, block->object_id, 2);
362
363 status = acpi_evaluate_object(handle, method, &input, out);
364
365 /*
366 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
367 * the WQxx method failed - we should disable collection anyway.
368 */
369 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
370 status = acpi_execute_simple_method(handle, wc_method, 0);
371 }
372
373 return status;
374}
375EXPORT_SYMBOL_GPL(wmi_query_block);
376
377/**
378 * wmi_set_block - Write to a WMI block
379 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
380 * @instance: Instance index
381 * &in: Buffer containing new values for the data block
382 *
383 * Write the contents of the input buffer to an ACPI-WMI data block
384 */
385acpi_status wmi_set_block(const char *guid_string, u8 instance,
386const struct acpi_buffer *in)
387{
388 struct guid_block *block = NULL;
389 struct wmi_block *wblock = NULL;
390 acpi_handle handle;
391 struct acpi_object_list input;
392 union acpi_object params[2];
393 char method[5] = "WS";
394
395 if (!guid_string || !in)
396 return AE_BAD_DATA;
397
398 if (!find_guid(guid_string, &wblock))
399 return AE_ERROR;
400
401 block = &wblock->gblock;
402 handle = wblock->handle;
403
404 if (block->instance_count < instance)
405 return AE_BAD_PARAMETER;
406
407 /* Check GUID is a data block */
408 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
409 return AE_ERROR;
410
411 input.count = 2;
412 input.pointer = params;
413 params[0].type = ACPI_TYPE_INTEGER;
414 params[0].integer.value = instance;
415
416 if (block->flags & ACPI_WMI_STRING) {
417 params[1].type = ACPI_TYPE_STRING;
418 } else {
419 params[1].type = ACPI_TYPE_BUFFER;
420 }
421 params[1].buffer.length = in->length;
422 params[1].buffer.pointer = in->pointer;
423
424 strncat(method, block->object_id, 2);
425
426 return acpi_evaluate_object(handle, method, &input, NULL);
427}
428EXPORT_SYMBOL_GPL(wmi_set_block);
429
430static void wmi_dump_wdg(const struct guid_block *g)
431{
432 pr_info("%pUL:\n", g->guid);
433 pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
434 pr_info("\tnotify_id: %02X\n", g->notify_id);
435 pr_info("\treserved: %02X\n", g->reserved);
436 pr_info("\tinstance_count: %d\n", g->instance_count);
437 pr_info("\tflags: %#x", g->flags);
438 if (g->flags) {
439 if (g->flags & ACPI_WMI_EXPENSIVE)
440 pr_cont(" ACPI_WMI_EXPENSIVE");
441 if (g->flags & ACPI_WMI_METHOD)
442 pr_cont(" ACPI_WMI_METHOD");
443 if (g->flags & ACPI_WMI_STRING)
444 pr_cont(" ACPI_WMI_STRING");
445 if (g->flags & ACPI_WMI_EVENT)
446 pr_cont(" ACPI_WMI_EVENT");
447 }
448 pr_cont("\n");
449
450}
451
452static void wmi_notify_debug(u32 value, void *context)
453{
454 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
455 union acpi_object *obj;
456 acpi_status status;
457
458 status = wmi_get_event_data(value, &response);
459 if (status != AE_OK) {
460 pr_info("bad event status 0x%x\n", status);
461 return;
462 }
463
464 obj = (union acpi_object *)response.pointer;
465
466 if (!obj)
467 return;
468
469 pr_info("DEBUG Event ");
470 switch(obj->type) {
471 case ACPI_TYPE_BUFFER:
472 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
473 break;
474 case ACPI_TYPE_STRING:
475 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
476 break;
477 case ACPI_TYPE_INTEGER:
478 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
479 break;
480 case ACPI_TYPE_PACKAGE:
481 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
482 break;
483 default:
484 pr_cont("object type 0x%X\n", obj->type);
485 }
486 kfree(obj);
487}
488
489/**
490 * wmi_install_notify_handler - Register handler for WMI events
491 * @handler: Function to handle notifications
492 * @data: Data to be returned to handler when event is fired
493 *
494 * Register a handler for events sent to the ACPI-WMI mapper device.
495 */
496acpi_status wmi_install_notify_handler(const char *guid,
497wmi_notify_handler handler, void *data)
498{
499 struct wmi_block *block;
500 acpi_status status = AE_NOT_EXIST;
501 char tmp[16], guid_input[16];
502 struct list_head *p;
503
504 if (!guid || !handler)
505 return AE_BAD_PARAMETER;
506
507 wmi_parse_guid(guid, tmp);
508 wmi_swap_bytes(tmp, guid_input);
509
510 list_for_each(p, &wmi_block_list) {
511 acpi_status wmi_status;
512 block = list_entry(p, struct wmi_block, list);
513
514 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
515 if (block->handler &&
516 block->handler != wmi_notify_debug)
517 return AE_ALREADY_ACQUIRED;
518
519 block->handler = handler;
520 block->handler_data = data;
521
522 wmi_status = wmi_method_enable(block, 1);
523 if ((wmi_status != AE_OK) ||
524 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
525 status = wmi_status;
526 }
527 }
528
529 return status;
530}
531EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
532
533/**
534 * wmi_uninstall_notify_handler - Unregister handler for WMI events
535 *
536 * Unregister handler for events sent to the ACPI-WMI mapper device.
537 */
538acpi_status wmi_remove_notify_handler(const char *guid)
539{
540 struct wmi_block *block;
541 acpi_status status = AE_NOT_EXIST;
542 char tmp[16], guid_input[16];
543 struct list_head *p;
544
545 if (!guid)
546 return AE_BAD_PARAMETER;
547
548 wmi_parse_guid(guid, tmp);
549 wmi_swap_bytes(tmp, guid_input);
550
551 list_for_each(p, &wmi_block_list) {
552 acpi_status wmi_status;
553 block = list_entry(p, struct wmi_block, list);
554
555 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
556 if (!block->handler ||
557 block->handler == wmi_notify_debug)
558 return AE_NULL_ENTRY;
559
560 if (debug_event) {
561 block->handler = wmi_notify_debug;
562 status = AE_OK;
563 } else {
564 wmi_status = wmi_method_enable(block, 0);
565 block->handler = NULL;
566 block->handler_data = NULL;
567 if ((wmi_status != AE_OK) ||
568 ((wmi_status == AE_OK) &&
569 (status == AE_NOT_EXIST)))
570 status = wmi_status;
571 }
572 }
573 }
574
575 return status;
576}
577EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
578
579/**
580 * wmi_get_event_data - Get WMI data associated with an event
581 *
582 * @event: Event to find
583 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
584 *
585 * Returns extra data associated with an event in WMI.
586 */
587acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
588{
589 struct acpi_object_list input;
590 union acpi_object params[1];
591 struct guid_block *gblock;
592 struct wmi_block *wblock;
593 struct list_head *p;
594
595 input.count = 1;
596 input.pointer = params;
597 params[0].type = ACPI_TYPE_INTEGER;
598 params[0].integer.value = event;
599
600 list_for_each(p, &wmi_block_list) {
601 wblock = list_entry(p, struct wmi_block, list);
602 gblock = &wblock->gblock;
603
604 if ((gblock->flags & ACPI_WMI_EVENT) &&
605 (gblock->notify_id == event))
606 return acpi_evaluate_object(wblock->handle, "_WED",
607 &input, out);
608 }
609
610 return AE_NOT_FOUND;
611}
612EXPORT_SYMBOL_GPL(wmi_get_event_data);
613
614/**
615 * wmi_has_guid - Check if a GUID is available
616 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
617 *
618 * Check if a given GUID is defined by _WDG
619 */
620bool wmi_has_guid(const char *guid_string)
621{
622 return find_guid(guid_string, NULL);
623}
624EXPORT_SYMBOL_GPL(wmi_has_guid);
625
626/*
627 * sysfs interface
628 */
629static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
630 char *buf)
631{
632 struct wmi_block *wblock;
633
634 wblock = dev_get_drvdata(dev);
635 if (!wblock) {
636 strcat(buf, "\n");
637 return strlen(buf);
638 }
639
640 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
641}
642static DEVICE_ATTR_RO(modalias);
643
644static struct attribute *wmi_attrs[] = {
645 &dev_attr_modalias.attr,
646 NULL,
647};
648ATTRIBUTE_GROUPS(wmi);
649
650static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
651{
652 char guid_string[37];
653
654 struct wmi_block *wblock;
655
656 if (add_uevent_var(env, "MODALIAS="))
657 return -ENOMEM;
658
659 wblock = dev_get_drvdata(dev);
660 if (!wblock)
661 return -ENOMEM;
662
663 sprintf(guid_string, "%pUL", wblock->gblock.guid);
664
665 strcpy(&env->buf[env->buflen - 1], "wmi:");
666 memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
667 env->buflen += 40;
668
669 return 0;
670}
671
672static void wmi_dev_free(struct device *dev)
673{
674 struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
675
676 kfree(wmi_block);
677}
678
679static struct class wmi_class = {
680 .name = "wmi",
681 .dev_release = wmi_dev_free,
682 .dev_uevent = wmi_dev_uevent,
683 .dev_groups = wmi_groups,
684};
685
686static int wmi_create_device(const struct guid_block *gblock,
687 struct wmi_block *wblock, acpi_handle handle)
688{
689 wblock->dev.class = &wmi_class;
690
691 dev_set_name(&wblock->dev, "%pUL", gblock->guid);
692
693 dev_set_drvdata(&wblock->dev, wblock);
694
695 return device_register(&wblock->dev);
696}
697
698static void wmi_free_devices(void)
699{
700 struct wmi_block *wblock, *next;
701
702 /* Delete devices for all the GUIDs */
703 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
704 list_del(&wblock->list);
705 if (wblock->dev.class)
706 device_unregister(&wblock->dev);
707 else
708 kfree(wblock);
709 }
710}
711
712static bool guid_already_parsed(const char *guid_string)
713{
714 struct wmi_block *wblock;
715
716 list_for_each_entry(wblock, &wmi_block_list, list)
717 if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
718 return true;
719
720 return false;
721}
722
723/*
724 * Parse the _WDG method for the GUID data blocks
725 */
726static int parse_wdg(acpi_handle handle)
727{
728 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
729 union acpi_object *obj;
730 const struct guid_block *gblock;
731 struct wmi_block *wblock;
732 acpi_status status;
733 int retval;
734 u32 i, total;
735
736 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
737 if (ACPI_FAILURE(status))
738 return -ENXIO;
739
740 obj = (union acpi_object *) out.pointer;
741 if (!obj)
742 return -ENXIO;
743
744 if (obj->type != ACPI_TYPE_BUFFER) {
745 retval = -ENXIO;
746 goto out_free_pointer;
747 }
748
749 gblock = (const struct guid_block *)obj->buffer.pointer;
750 total = obj->buffer.length / sizeof(struct guid_block);
751
752 for (i = 0; i < total; i++) {
753 if (debug_dump_wdg)
754 wmi_dump_wdg(&gblock[i]);
755
756 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
757 if (!wblock)
758 return -ENOMEM;
759
760 wblock->handle = handle;
761 wblock->gblock = gblock[i];
762
763 /*
764 Some WMI devices, like those for nVidia hooks, have a
765 duplicate GUID. It's not clear what we should do in this
766 case yet, so for now, we'll just ignore the duplicate
767 for device creation.
768 */
769 if (!guid_already_parsed(gblock[i].guid)) {
770 retval = wmi_create_device(&gblock[i], wblock, handle);
771 if (retval) {
772 wmi_free_devices();
773 goto out_free_pointer;
774 }
775 }
776
777 list_add_tail(&wblock->list, &wmi_block_list);
778
779 if (debug_event) {
780 wblock->handler = wmi_notify_debug;
781 wmi_method_enable(wblock, 1);
782 }
783 }
784
785 retval = 0;
786
787out_free_pointer:
788 kfree(out.pointer);
789
790 return retval;
791}
792
793/*
794 * WMI can have EmbeddedControl access regions. In which case, we just want to
795 * hand these off to the EC driver.
796 */
797static acpi_status
798acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
799 u32 bits, u64 *value,
800 void *handler_context, void *region_context)
801{
802 int result = 0, i = 0;
803 u8 temp = 0;
804
805 if ((address > 0xFF) || !value)
806 return AE_BAD_PARAMETER;
807
808 if (function != ACPI_READ && function != ACPI_WRITE)
809 return AE_BAD_PARAMETER;
810
811 if (bits != 8)
812 return AE_BAD_PARAMETER;
813
814 if (function == ACPI_READ) {
815 result = ec_read(address, &temp);
816 (*value) |= ((u64)temp) << i;
817 } else {
818 temp = 0xff & ((*value) >> i);
819 result = ec_write(address, temp);
820 }
821
822 switch (result) {
823 case -EINVAL:
824 return AE_BAD_PARAMETER;
825 break;
826 case -ENODEV:
827 return AE_NOT_FOUND;
828 break;
829 case -ETIME:
830 return AE_TIME;
831 break;
832 default:
833 return AE_OK;
834 }
835}
836
837static void acpi_wmi_notify(struct acpi_device *device, u32 event)
838{
839 struct guid_block *block;
840 struct wmi_block *wblock;
841 struct list_head *p;
842
843 list_for_each(p, &wmi_block_list) {
844 wblock = list_entry(p, struct wmi_block, list);
845 block = &wblock->gblock;
846
847 if ((block->flags & ACPI_WMI_EVENT) &&
848 (block->notify_id == event)) {
849 if (wblock->handler)
850 wblock->handler(event, wblock->handler_data);
851 if (debug_event) {
852 pr_info("DEBUG Event GUID: %pUL\n",
853 wblock->gblock.guid);
854 }
855
856 acpi_bus_generate_netlink_event(
857 device->pnp.device_class, dev_name(&device->dev),
858 event, 0);
859 break;
860 }
861 }
862}
863
864static int acpi_wmi_remove(struct acpi_device *device)
865{
866 acpi_remove_address_space_handler(device->handle,
867 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
868 wmi_free_devices();
869
870 return 0;
871}
872
873static int acpi_wmi_add(struct acpi_device *device)
874{
875 acpi_status status;
876 int error;
877
878 status = acpi_install_address_space_handler(device->handle,
879 ACPI_ADR_SPACE_EC,
880 &acpi_wmi_ec_space_handler,
881 NULL, NULL);
882 if (ACPI_FAILURE(status)) {
883 pr_err("Error installing EC region handler\n");
884 return -ENODEV;
885 }
886
887 error = parse_wdg(device->handle);
888 if (error) {
889 acpi_remove_address_space_handler(device->handle,
890 ACPI_ADR_SPACE_EC,
891 &acpi_wmi_ec_space_handler);
892 pr_err("Failed to parse WDG method\n");
893 return error;
894 }
895
896 return 0;
897}
898
899static int __init acpi_wmi_init(void)
900{
901 int error;
902
903 if (acpi_disabled)
904 return -ENODEV;
905
906 error = class_register(&wmi_class);
907 if (error)
908 return error;
909
910 error = acpi_bus_register_driver(&acpi_wmi_driver);
911 if (error) {
912 pr_err("Error loading mapper\n");
913 class_unregister(&wmi_class);
914 return error;
915 }
916
917 pr_info("Mapper loaded\n");
918 return 0;
919}
920
921static void __exit acpi_wmi_exit(void)
922{
923 acpi_bus_unregister_driver(&acpi_wmi_driver);
924 class_unregister(&wmi_class);
925
926 pr_info("Mapper unloaded\n");
927}
928
929subsys_initcall(acpi_wmi_init);
930module_exit(acpi_wmi_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ACPI-WMI mapping driver
4 *
5 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
6 *
7 * GUID parsing code from ldm.c is:
8 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
9 * Copyright (c) 2001-2007 Anton Altaparmakov
10 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
11 *
12 * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
13 * Copyright (C) 2015 Andrew Lutomirski
14 * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include <linux/acpi.h>
20#include <linux/bits.h>
21#include <linux/build_bug.h>
22#include <linux/device.h>
23#include <linux/init.h>
24#include <linux/kernel.h>
25#include <linux/list.h>
26#include <linux/module.h>
27#include <linux/platform_device.h>
28#include <linux/rwsem.h>
29#include <linux/slab.h>
30#include <linux/sysfs.h>
31#include <linux/types.h>
32#include <linux/uuid.h>
33#include <linux/wmi.h>
34#include <linux/fs.h>
35
36MODULE_AUTHOR("Carlos Corbacho");
37MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
38MODULE_LICENSE("GPL");
39
40static LIST_HEAD(wmi_block_list);
41
42struct guid_block {
43 guid_t guid;
44 union {
45 char object_id[2];
46 struct {
47 unsigned char notify_id;
48 unsigned char reserved;
49 };
50 };
51 u8 instance_count;
52 u8 flags;
53} __packed;
54static_assert(sizeof(typeof_member(struct guid_block, guid)) == 16);
55static_assert(sizeof(struct guid_block) == 20);
56static_assert(__alignof__(struct guid_block) == 1);
57
58enum { /* wmi_block flags */
59 WMI_READ_TAKES_NO_ARGS,
60 WMI_GUID_DUPLICATED,
61 WMI_NO_EVENT_DATA,
62};
63
64struct wmi_block {
65 struct wmi_device dev;
66 struct list_head list;
67 struct guid_block gblock;
68 struct acpi_device *acpi_device;
69 struct rw_semaphore notify_lock; /* Protects notify callback add/remove */
70 wmi_notify_handler handler;
71 void *handler_data;
72 bool driver_ready;
73 unsigned long flags;
74};
75
76
77/*
78 * If the GUID data block is marked as expensive, we must enable and
79 * explicitily disable data collection.
80 */
81#define ACPI_WMI_EXPENSIVE BIT(0)
82#define ACPI_WMI_METHOD BIT(1) /* GUID is a method */
83#define ACPI_WMI_STRING BIT(2) /* GUID takes & returns a string */
84#define ACPI_WMI_EVENT BIT(3) /* GUID is an event */
85
86static const struct acpi_device_id wmi_device_ids[] = {
87 {"PNP0C14", 0},
88 {"pnp0c14", 0},
89 { }
90};
91MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
92
93#define dev_to_wblock(__dev) container_of_const(__dev, struct wmi_block, dev.dev)
94#define dev_to_wdev(__dev) container_of_const(__dev, struct wmi_device, dev)
95
96/*
97 * GUID parsing functions
98 */
99
100static bool guid_parse_and_compare(const char *string, const guid_t *guid)
101{
102 guid_t guid_input;
103
104 if (guid_parse(string, &guid_input))
105 return false;
106
107 return guid_equal(&guid_input, guid);
108}
109
110static const void *find_guid_context(struct wmi_block *wblock,
111 struct wmi_driver *wdriver)
112{
113 const struct wmi_device_id *id;
114
115 id = wdriver->id_table;
116 if (!id)
117 return NULL;
118
119 while (*id->guid_string) {
120 if (guid_parse_and_compare(id->guid_string, &wblock->gblock.guid))
121 return id->context;
122 id++;
123 }
124 return NULL;
125}
126
127static acpi_status wmi_method_enable(struct wmi_block *wblock, bool enable)
128{
129 struct guid_block *block;
130 char method[5];
131 acpi_status status;
132 acpi_handle handle;
133
134 block = &wblock->gblock;
135 handle = wblock->acpi_device->handle;
136
137 snprintf(method, 5, "WE%02X", block->notify_id);
138 status = acpi_execute_simple_method(handle, method, enable);
139 if (status == AE_NOT_FOUND)
140 return AE_OK;
141
142 return status;
143}
144
145#define WMI_ACPI_METHOD_NAME_SIZE 5
146
147static inline void get_acpi_method_name(const struct wmi_block *wblock,
148 const char method,
149 char buffer[static WMI_ACPI_METHOD_NAME_SIZE])
150{
151 static_assert(ARRAY_SIZE(wblock->gblock.object_id) == 2);
152 static_assert(WMI_ACPI_METHOD_NAME_SIZE >= 5);
153
154 buffer[0] = 'W';
155 buffer[1] = method;
156 buffer[2] = wblock->gblock.object_id[0];
157 buffer[3] = wblock->gblock.object_id[1];
158 buffer[4] = '\0';
159}
160
161static inline acpi_object_type get_param_acpi_type(const struct wmi_block *wblock)
162{
163 if (wblock->gblock.flags & ACPI_WMI_STRING)
164 return ACPI_TYPE_STRING;
165 else
166 return ACPI_TYPE_BUFFER;
167}
168
169static acpi_status get_event_data(const struct wmi_block *wblock, struct acpi_buffer *out)
170{
171 union acpi_object param = {
172 .integer = {
173 .type = ACPI_TYPE_INTEGER,
174 .value = wblock->gblock.notify_id,
175 }
176 };
177 struct acpi_object_list input = {
178 .count = 1,
179 .pointer = ¶m,
180 };
181
182 return acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, out);
183}
184
185static int wmidev_match_guid(struct device *dev, const void *data)
186{
187 struct wmi_block *wblock = dev_to_wblock(dev);
188 const guid_t *guid = data;
189
190 /* Legacy GUID-based functions are restricted to only see
191 * a single WMI device for each GUID.
192 */
193 if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags))
194 return 0;
195
196 if (guid_equal(guid, &wblock->gblock.guid))
197 return 1;
198
199 return 0;
200}
201
202static int wmidev_match_notify_id(struct device *dev, const void *data)
203{
204 struct wmi_block *wblock = dev_to_wblock(dev);
205 const u32 *notify_id = data;
206
207 /* Legacy GUID-based functions are restricted to only see
208 * a single WMI device for each GUID.
209 */
210 if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags))
211 return 0;
212
213 if (wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *notify_id)
214 return 1;
215
216 return 0;
217}
218
219static const struct bus_type wmi_bus_type;
220
221static struct wmi_device *wmi_find_device_by_guid(const char *guid_string)
222{
223 struct device *dev;
224 guid_t guid;
225 int ret;
226
227 ret = guid_parse(guid_string, &guid);
228 if (ret < 0)
229 return ERR_PTR(ret);
230
231 dev = bus_find_device(&wmi_bus_type, NULL, &guid, wmidev_match_guid);
232 if (!dev)
233 return ERR_PTR(-ENODEV);
234
235 return dev_to_wdev(dev);
236}
237
238static struct wmi_device *wmi_find_event_by_notify_id(const u32 notify_id)
239{
240 struct device *dev;
241
242 dev = bus_find_device(&wmi_bus_type, NULL, ¬ify_id, wmidev_match_notify_id);
243 if (!dev)
244 return ERR_PTR(-ENODEV);
245
246 return to_wmi_device(dev);
247}
248
249static void wmi_device_put(struct wmi_device *wdev)
250{
251 put_device(&wdev->dev);
252}
253
254/*
255 * Exported WMI functions
256 */
257
258/**
259 * wmi_instance_count - Get number of WMI object instances
260 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
261 *
262 * Get the number of WMI object instances.
263 *
264 * Returns: Number of WMI object instances or negative error code.
265 */
266int wmi_instance_count(const char *guid_string)
267{
268 struct wmi_device *wdev;
269 int ret;
270
271 wdev = wmi_find_device_by_guid(guid_string);
272 if (IS_ERR(wdev))
273 return PTR_ERR(wdev);
274
275 ret = wmidev_instance_count(wdev);
276 wmi_device_put(wdev);
277
278 return ret;
279}
280EXPORT_SYMBOL_GPL(wmi_instance_count);
281
282/**
283 * wmidev_instance_count - Get number of WMI object instances
284 * @wdev: A wmi bus device from a driver
285 *
286 * Get the number of WMI object instances.
287 *
288 * Returns: Number of WMI object instances.
289 */
290u8 wmidev_instance_count(struct wmi_device *wdev)
291{
292 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
293
294 return wblock->gblock.instance_count;
295}
296EXPORT_SYMBOL_GPL(wmidev_instance_count);
297
298/**
299 * wmi_evaluate_method - Evaluate a WMI method (deprecated)
300 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
301 * @instance: Instance index
302 * @method_id: Method ID to call
303 * @in: Mandatory buffer containing input for the method call
304 * @out: Empty buffer to return the method results
305 *
306 * Call an ACPI-WMI method, the caller must free @out.
307 *
308 * Return: acpi_status signaling success or error.
309 */
310acpi_status wmi_evaluate_method(const char *guid_string, u8 instance, u32 method_id,
311 const struct acpi_buffer *in, struct acpi_buffer *out)
312{
313 struct wmi_device *wdev;
314 acpi_status status;
315
316 wdev = wmi_find_device_by_guid(guid_string);
317 if (IS_ERR(wdev))
318 return AE_ERROR;
319
320 status = wmidev_evaluate_method(wdev, instance, method_id, in, out);
321
322 wmi_device_put(wdev);
323
324 return status;
325}
326EXPORT_SYMBOL_GPL(wmi_evaluate_method);
327
328/**
329 * wmidev_evaluate_method - Evaluate a WMI method
330 * @wdev: A wmi bus device from a driver
331 * @instance: Instance index
332 * @method_id: Method ID to call
333 * @in: Mandatory buffer containing input for the method call
334 * @out: Empty buffer to return the method results
335 *
336 * Call an ACPI-WMI method, the caller must free @out.
337 *
338 * Return: acpi_status signaling success or error.
339 */
340acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance, u32 method_id,
341 const struct acpi_buffer *in, struct acpi_buffer *out)
342{
343 struct guid_block *block;
344 struct wmi_block *wblock;
345 acpi_handle handle;
346 struct acpi_object_list input;
347 union acpi_object params[3];
348 char method[WMI_ACPI_METHOD_NAME_SIZE];
349
350 wblock = container_of(wdev, struct wmi_block, dev);
351 block = &wblock->gblock;
352 handle = wblock->acpi_device->handle;
353
354 if (!in)
355 return AE_BAD_DATA;
356
357 if (!(block->flags & ACPI_WMI_METHOD))
358 return AE_BAD_DATA;
359
360 if (block->instance_count <= instance)
361 return AE_BAD_PARAMETER;
362
363 input.count = 3;
364 input.pointer = params;
365
366 params[0].type = ACPI_TYPE_INTEGER;
367 params[0].integer.value = instance;
368 params[1].type = ACPI_TYPE_INTEGER;
369 params[1].integer.value = method_id;
370 params[2].type = get_param_acpi_type(wblock);
371 params[2].buffer.length = in->length;
372 params[2].buffer.pointer = in->pointer;
373
374 get_acpi_method_name(wblock, 'M', method);
375
376 return acpi_evaluate_object(handle, method, &input, out);
377}
378EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
379
380static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
381 struct acpi_buffer *out)
382{
383 struct guid_block *block;
384 acpi_handle handle;
385 acpi_status status, wc_status = AE_ERROR;
386 struct acpi_object_list input;
387 union acpi_object wq_params[1];
388 char wc_method[WMI_ACPI_METHOD_NAME_SIZE];
389 char method[WMI_ACPI_METHOD_NAME_SIZE];
390
391 if (!out)
392 return AE_BAD_PARAMETER;
393
394 block = &wblock->gblock;
395 handle = wblock->acpi_device->handle;
396
397 if (block->instance_count <= instance)
398 return AE_BAD_PARAMETER;
399
400 /* Check GUID is a data block */
401 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
402 return AE_ERROR;
403
404 input.count = 1;
405 input.pointer = wq_params;
406 wq_params[0].type = ACPI_TYPE_INTEGER;
407 wq_params[0].integer.value = instance;
408
409 if (instance == 0 && test_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags))
410 input.count = 0;
411
412 /*
413 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
414 * enable collection.
415 */
416 if (block->flags & ACPI_WMI_EXPENSIVE) {
417 get_acpi_method_name(wblock, 'C', wc_method);
418
419 /*
420 * Some GUIDs break the specification by declaring themselves
421 * expensive, but have no corresponding WCxx method. So we
422 * should not fail if this happens.
423 */
424 wc_status = acpi_execute_simple_method(handle, wc_method, 1);
425 }
426
427 get_acpi_method_name(wblock, 'Q', method);
428 status = acpi_evaluate_object(handle, method, &input, out);
429
430 /*
431 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
432 * the WQxx method failed - we should disable collection anyway.
433 */
434 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
435 /*
436 * Ignore whether this WCxx call succeeds or not since
437 * the previously executed WQxx method call might have
438 * succeeded, and returning the failing status code
439 * of this call would throw away the result of the WQxx
440 * call, potentially leaking memory.
441 */
442 acpi_execute_simple_method(handle, wc_method, 0);
443 }
444
445 return status;
446}
447
448/**
449 * wmi_query_block - Return contents of a WMI block (deprecated)
450 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
451 * @instance: Instance index
452 * @out: Empty buffer to return the contents of the data block to
453 *
454 * Query a ACPI-WMI block, the caller must free @out.
455 *
456 * Return: ACPI object containing the content of the WMI block.
457 */
458acpi_status wmi_query_block(const char *guid_string, u8 instance,
459 struct acpi_buffer *out)
460{
461 struct wmi_block *wblock;
462 struct wmi_device *wdev;
463 acpi_status status;
464
465 wdev = wmi_find_device_by_guid(guid_string);
466 if (IS_ERR(wdev))
467 return AE_ERROR;
468
469 wblock = container_of(wdev, struct wmi_block, dev);
470 status = __query_block(wblock, instance, out);
471
472 wmi_device_put(wdev);
473
474 return status;
475}
476EXPORT_SYMBOL_GPL(wmi_query_block);
477
478/**
479 * wmidev_block_query - Return contents of a WMI block
480 * @wdev: A wmi bus device from a driver
481 * @instance: Instance index
482 *
483 * Query an ACPI-WMI block, the caller must free the result.
484 *
485 * Return: ACPI object containing the content of the WMI block.
486 */
487union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
488{
489 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
490 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
491
492 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
493 return NULL;
494
495 return out.pointer;
496}
497EXPORT_SYMBOL_GPL(wmidev_block_query);
498
499/**
500 * wmi_set_block - Write to a WMI block (deprecated)
501 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
502 * @instance: Instance index
503 * @in: Buffer containing new values for the data block
504 *
505 * Write the contents of the input buffer to an ACPI-WMI data block.
506 *
507 * Return: acpi_status signaling success or error.
508 */
509acpi_status wmi_set_block(const char *guid_string, u8 instance, const struct acpi_buffer *in)
510{
511 struct wmi_device *wdev;
512 acpi_status status;
513
514 wdev = wmi_find_device_by_guid(guid_string);
515 if (IS_ERR(wdev))
516 return AE_ERROR;
517
518 status = wmidev_block_set(wdev, instance, in);
519 wmi_device_put(wdev);
520
521 return status;
522}
523EXPORT_SYMBOL_GPL(wmi_set_block);
524
525/**
526 * wmidev_block_set - Write to a WMI block
527 * @wdev: A wmi bus device from a driver
528 * @instance: Instance index
529 * @in: Buffer containing new values for the data block
530 *
531 * Write contents of the input buffer to an ACPI-WMI data block.
532 *
533 * Return: acpi_status signaling success or error.
534 */
535acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in)
536{
537 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
538 acpi_handle handle = wblock->acpi_device->handle;
539 struct guid_block *block = &wblock->gblock;
540 char method[WMI_ACPI_METHOD_NAME_SIZE];
541 struct acpi_object_list input;
542 union acpi_object params[2];
543
544 if (!in)
545 return AE_BAD_DATA;
546
547 if (block->instance_count <= instance)
548 return AE_BAD_PARAMETER;
549
550 /* Check GUID is a data block */
551 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
552 return AE_ERROR;
553
554 input.count = 2;
555 input.pointer = params;
556 params[0].type = ACPI_TYPE_INTEGER;
557 params[0].integer.value = instance;
558 params[1].type = get_param_acpi_type(wblock);
559 params[1].buffer.length = in->length;
560 params[1].buffer.pointer = in->pointer;
561
562 get_acpi_method_name(wblock, 'S', method);
563
564 return acpi_evaluate_object(handle, method, &input, NULL);
565}
566EXPORT_SYMBOL_GPL(wmidev_block_set);
567
568/**
569 * wmi_install_notify_handler - Register handler for WMI events (deprecated)
570 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
571 * @handler: Function to handle notifications
572 * @data: Data to be returned to handler when event is fired
573 *
574 * Register a handler for events sent to the ACPI-WMI mapper device.
575 *
576 * Return: acpi_status signaling success or error.
577 */
578acpi_status wmi_install_notify_handler(const char *guid,
579 wmi_notify_handler handler,
580 void *data)
581{
582 struct wmi_block *wblock;
583 struct wmi_device *wdev;
584 acpi_status status;
585
586 wdev = wmi_find_device_by_guid(guid);
587 if (IS_ERR(wdev))
588 return AE_ERROR;
589
590 wblock = container_of(wdev, struct wmi_block, dev);
591
592 down_write(&wblock->notify_lock);
593 if (wblock->handler) {
594 status = AE_ALREADY_ACQUIRED;
595 } else {
596 wblock->handler = handler;
597 wblock->handler_data = data;
598
599 if (ACPI_FAILURE(wmi_method_enable(wblock, true)))
600 dev_warn(&wblock->dev.dev, "Failed to enable device\n");
601
602 status = AE_OK;
603 }
604 up_write(&wblock->notify_lock);
605
606 wmi_device_put(wdev);
607
608 return status;
609}
610EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
611
612/**
613 * wmi_remove_notify_handler - Unregister handler for WMI events (deprecated)
614 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
615 *
616 * Unregister handler for events sent to the ACPI-WMI mapper device.
617 *
618 * Return: acpi_status signaling success or error.
619 */
620acpi_status wmi_remove_notify_handler(const char *guid)
621{
622 struct wmi_block *wblock;
623 struct wmi_device *wdev;
624 acpi_status status;
625
626 wdev = wmi_find_device_by_guid(guid);
627 if (IS_ERR(wdev))
628 return AE_ERROR;
629
630 wblock = container_of(wdev, struct wmi_block, dev);
631
632 down_write(&wblock->notify_lock);
633 if (!wblock->handler) {
634 status = AE_NULL_ENTRY;
635 } else {
636 if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
637 dev_warn(&wblock->dev.dev, "Failed to disable device\n");
638
639 wblock->handler = NULL;
640 wblock->handler_data = NULL;
641
642 status = AE_OK;
643 }
644 up_write(&wblock->notify_lock);
645
646 wmi_device_put(wdev);
647
648 return status;
649}
650EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
651
652/**
653 * wmi_get_event_data - Get WMI data associated with an event (deprecated)
654 *
655 * @event: Event to find
656 * @out: Buffer to hold event data
657 *
658 * Get extra data associated with an WMI event, the caller needs to free @out.
659 *
660 * Return: acpi_status signaling success or error.
661 */
662acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
663{
664 struct wmi_block *wblock;
665 struct wmi_device *wdev;
666 acpi_status status;
667
668 wdev = wmi_find_event_by_notify_id(event);
669 if (IS_ERR(wdev))
670 return AE_NOT_FOUND;
671
672 wblock = container_of(wdev, struct wmi_block, dev);
673 status = get_event_data(wblock, out);
674
675 wmi_device_put(wdev);
676
677 return status;
678}
679EXPORT_SYMBOL_GPL(wmi_get_event_data);
680
681/**
682 * wmi_has_guid - Check if a GUID is available
683 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
684 *
685 * Check if a given GUID is defined by _WDG.
686 *
687 * Return: True if GUID is available, false otherwise.
688 */
689bool wmi_has_guid(const char *guid_string)
690{
691 struct wmi_device *wdev;
692
693 wdev = wmi_find_device_by_guid(guid_string);
694 if (IS_ERR(wdev))
695 return false;
696
697 wmi_device_put(wdev);
698
699 return true;
700}
701EXPORT_SYMBOL_GPL(wmi_has_guid);
702
703/**
704 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID (deprecated)
705 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
706 *
707 * Find the _UID of ACPI device associated with this WMI GUID.
708 *
709 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found.
710 */
711char *wmi_get_acpi_device_uid(const char *guid_string)
712{
713 struct wmi_block *wblock;
714 struct wmi_device *wdev;
715 char *uid;
716
717 wdev = wmi_find_device_by_guid(guid_string);
718 if (IS_ERR(wdev))
719 return NULL;
720
721 wblock = container_of(wdev, struct wmi_block, dev);
722 uid = acpi_device_uid(wblock->acpi_device);
723
724 wmi_device_put(wdev);
725
726 return uid;
727}
728EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
729
730static inline struct wmi_driver *drv_to_wdrv(struct device_driver *drv)
731{
732 return container_of(drv, struct wmi_driver, driver);
733}
734
735/*
736 * sysfs interface
737 */
738static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
739 char *buf)
740{
741 struct wmi_block *wblock = dev_to_wblock(dev);
742
743 return sysfs_emit(buf, "wmi:%pUL\n", &wblock->gblock.guid);
744}
745static DEVICE_ATTR_RO(modalias);
746
747static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
748 char *buf)
749{
750 struct wmi_block *wblock = dev_to_wblock(dev);
751
752 return sysfs_emit(buf, "%pUL\n", &wblock->gblock.guid);
753}
754static DEVICE_ATTR_RO(guid);
755
756static ssize_t instance_count_show(struct device *dev,
757 struct device_attribute *attr, char *buf)
758{
759 struct wmi_block *wblock = dev_to_wblock(dev);
760
761 return sysfs_emit(buf, "%d\n", (int)wblock->gblock.instance_count);
762}
763static DEVICE_ATTR_RO(instance_count);
764
765static ssize_t expensive_show(struct device *dev,
766 struct device_attribute *attr, char *buf)
767{
768 struct wmi_block *wblock = dev_to_wblock(dev);
769
770 return sysfs_emit(buf, "%d\n",
771 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
772}
773static DEVICE_ATTR_RO(expensive);
774
775static struct attribute *wmi_attrs[] = {
776 &dev_attr_modalias.attr,
777 &dev_attr_guid.attr,
778 &dev_attr_instance_count.attr,
779 &dev_attr_expensive.attr,
780 NULL
781};
782ATTRIBUTE_GROUPS(wmi);
783
784static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
785 char *buf)
786{
787 struct wmi_block *wblock = dev_to_wblock(dev);
788
789 return sysfs_emit(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
790}
791static DEVICE_ATTR_RO(notify_id);
792
793static struct attribute *wmi_event_attrs[] = {
794 &dev_attr_notify_id.attr,
795 NULL
796};
797ATTRIBUTE_GROUPS(wmi_event);
798
799static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
800 char *buf)
801{
802 struct wmi_block *wblock = dev_to_wblock(dev);
803
804 return sysfs_emit(buf, "%c%c\n", wblock->gblock.object_id[0],
805 wblock->gblock.object_id[1]);
806}
807static DEVICE_ATTR_RO(object_id);
808
809static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
810 char *buf)
811{
812 struct wmi_device *wdev = dev_to_wdev(dev);
813
814 return sysfs_emit(buf, "%d\n", (int)wdev->setable);
815}
816static DEVICE_ATTR_RO(setable);
817
818static struct attribute *wmi_data_attrs[] = {
819 &dev_attr_object_id.attr,
820 &dev_attr_setable.attr,
821 NULL
822};
823ATTRIBUTE_GROUPS(wmi_data);
824
825static struct attribute *wmi_method_attrs[] = {
826 &dev_attr_object_id.attr,
827 NULL
828};
829ATTRIBUTE_GROUPS(wmi_method);
830
831static int wmi_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
832{
833 const struct wmi_block *wblock = dev_to_wblock(dev);
834
835 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", &wblock->gblock.guid))
836 return -ENOMEM;
837
838 if (add_uevent_var(env, "WMI_GUID=%pUL", &wblock->gblock.guid))
839 return -ENOMEM;
840
841 return 0;
842}
843
844static void wmi_dev_release(struct device *dev)
845{
846 struct wmi_block *wblock = dev_to_wblock(dev);
847
848 kfree(wblock);
849}
850
851static int wmi_dev_match(struct device *dev, struct device_driver *driver)
852{
853 struct wmi_driver *wmi_driver = drv_to_wdrv(driver);
854 struct wmi_block *wblock = dev_to_wblock(dev);
855 const struct wmi_device_id *id = wmi_driver->id_table;
856
857 if (id == NULL)
858 return 0;
859
860 while (*id->guid_string) {
861 if (guid_parse_and_compare(id->guid_string, &wblock->gblock.guid))
862 return 1;
863
864 id++;
865 }
866
867 return 0;
868}
869
870static int wmi_dev_probe(struct device *dev)
871{
872 struct wmi_block *wblock = dev_to_wblock(dev);
873 struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
874 int ret = 0;
875
876 /* Some older WMI drivers will break if instantiated multiple times,
877 * so they are blocked from probing WMI devices with a duplicated GUID.
878 *
879 * New WMI drivers should support being instantiated multiple times.
880 */
881 if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags) && !wdriver->no_singleton) {
882 dev_warn(dev, "Legacy driver %s cannot be instantiated multiple times\n",
883 dev->driver->name);
884
885 return -ENODEV;
886 }
887
888 if (wdriver->notify) {
889 if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags) && !wdriver->no_notify_data)
890 return -ENODEV;
891 }
892
893 if (ACPI_FAILURE(wmi_method_enable(wblock, true)))
894 dev_warn(dev, "failed to enable device -- probing anyway\n");
895
896 if (wdriver->probe) {
897 ret = wdriver->probe(dev_to_wdev(dev),
898 find_guid_context(wblock, wdriver));
899 if (ret) {
900 if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
901 dev_warn(dev, "Failed to disable device\n");
902
903 return ret;
904 }
905 }
906
907 down_write(&wblock->notify_lock);
908 wblock->driver_ready = true;
909 up_write(&wblock->notify_lock);
910
911 return 0;
912}
913
914static void wmi_dev_remove(struct device *dev)
915{
916 struct wmi_block *wblock = dev_to_wblock(dev);
917 struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
918
919 down_write(&wblock->notify_lock);
920 wblock->driver_ready = false;
921 up_write(&wblock->notify_lock);
922
923 if (wdriver->remove)
924 wdriver->remove(dev_to_wdev(dev));
925
926 if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
927 dev_warn(dev, "failed to disable device\n");
928}
929
930static struct class wmi_bus_class = {
931 .name = "wmi_bus",
932};
933
934static const struct bus_type wmi_bus_type = {
935 .name = "wmi",
936 .dev_groups = wmi_groups,
937 .match = wmi_dev_match,
938 .uevent = wmi_dev_uevent,
939 .probe = wmi_dev_probe,
940 .remove = wmi_dev_remove,
941};
942
943static const struct device_type wmi_type_event = {
944 .name = "event",
945 .groups = wmi_event_groups,
946 .release = wmi_dev_release,
947};
948
949static const struct device_type wmi_type_method = {
950 .name = "method",
951 .groups = wmi_method_groups,
952 .release = wmi_dev_release,
953};
954
955static const struct device_type wmi_type_data = {
956 .name = "data",
957 .groups = wmi_data_groups,
958 .release = wmi_dev_release,
959};
960
961/*
962 * _WDG is a static list that is only parsed at startup,
963 * so it's safe to count entries without extra protection.
964 */
965static int guid_count(const guid_t *guid)
966{
967 struct wmi_block *wblock;
968 int count = 0;
969
970 list_for_each_entry(wblock, &wmi_block_list, list) {
971 if (guid_equal(&wblock->gblock.guid, guid))
972 count++;
973 }
974
975 return count;
976}
977
978static int wmi_create_device(struct device *wmi_bus_dev,
979 struct wmi_block *wblock,
980 struct acpi_device *device)
981{
982 char method[WMI_ACPI_METHOD_NAME_SIZE];
983 struct acpi_device_info *info;
984 acpi_handle method_handle;
985 acpi_status status;
986 uint count;
987
988 if (wblock->gblock.flags & ACPI_WMI_EVENT) {
989 wblock->dev.dev.type = &wmi_type_event;
990 goto out_init;
991 }
992
993 if (wblock->gblock.flags & ACPI_WMI_METHOD) {
994 get_acpi_method_name(wblock, 'M', method);
995 if (!acpi_has_method(device->handle, method)) {
996 dev_warn(wmi_bus_dev,
997 FW_BUG "%s method block execution control method not found\n",
998 method);
999
1000 return -ENXIO;
1001 }
1002
1003 wblock->dev.dev.type = &wmi_type_method;
1004 goto out_init;
1005 }
1006
1007 /*
1008 * Data Block Query Control Method (WQxx by convention) is
1009 * required per the WMI documentation. If it is not present,
1010 * we ignore this data block.
1011 */
1012 get_acpi_method_name(wblock, 'Q', method);
1013 status = acpi_get_handle(device->handle, method, &method_handle);
1014 if (ACPI_FAILURE(status)) {
1015 dev_warn(wmi_bus_dev,
1016 FW_BUG "%s data block query control method not found\n",
1017 method);
1018
1019 return -ENXIO;
1020 }
1021
1022 status = acpi_get_object_info(method_handle, &info);
1023 if (ACPI_FAILURE(status))
1024 return -EIO;
1025
1026 wblock->dev.dev.type = &wmi_type_data;
1027
1028 /*
1029 * The Microsoft documentation specifically states:
1030 *
1031 * Data blocks registered with only a single instance
1032 * can ignore the parameter.
1033 *
1034 * ACPICA will get mad at us if we call the method with the wrong number
1035 * of arguments, so check what our method expects. (On some Dell
1036 * laptops, WQxx may not be a method at all.)
1037 */
1038 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1039 set_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags);
1040
1041 kfree(info);
1042
1043 get_acpi_method_name(wblock, 'S', method);
1044 if (acpi_has_method(device->handle, method))
1045 wblock->dev.setable = true;
1046
1047 out_init:
1048 init_rwsem(&wblock->notify_lock);
1049 wblock->driver_ready = false;
1050 wblock->dev.dev.bus = &wmi_bus_type;
1051 wblock->dev.dev.parent = wmi_bus_dev;
1052
1053 count = guid_count(&wblock->gblock.guid);
1054 if (count) {
1055 dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, count);
1056 set_bit(WMI_GUID_DUPLICATED, &wblock->flags);
1057 } else {
1058 dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid);
1059 }
1060
1061 device_initialize(&wblock->dev.dev);
1062
1063 return 0;
1064}
1065
1066static int wmi_add_device(struct platform_device *pdev, struct wmi_device *wdev)
1067{
1068 struct device_link *link;
1069
1070 /*
1071 * Many aggregate WMI drivers do not use -EPROBE_DEFER when they
1072 * are unable to find a WMI device during probe, instead they require
1073 * all WMI devices associated with an platform device to become available
1074 * at once. This device link thus prevents WMI drivers from probing until
1075 * the associated platform device has finished probing (and has registered
1076 * all discovered WMI devices).
1077 */
1078
1079 link = device_link_add(&wdev->dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
1080 if (!link)
1081 return -EINVAL;
1082
1083 return device_add(&wdev->dev);
1084}
1085
1086/*
1087 * Parse the _WDG method for the GUID data blocks
1088 */
1089static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev)
1090{
1091 struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
1092 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
1093 const struct guid_block *gblock;
1094 bool event_data_available;
1095 struct wmi_block *wblock;
1096 union acpi_object *obj;
1097 acpi_status status;
1098 u32 i, total;
1099 int retval;
1100
1101 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1102 if (ACPI_FAILURE(status))
1103 return -ENXIO;
1104
1105 obj = out.pointer;
1106 if (!obj)
1107 return -ENXIO;
1108
1109 if (obj->type != ACPI_TYPE_BUFFER) {
1110 kfree(obj);
1111 return -ENXIO;
1112 }
1113
1114 event_data_available = acpi_has_method(device->handle, "_WED");
1115 gblock = (const struct guid_block *)obj->buffer.pointer;
1116 total = obj->buffer.length / sizeof(struct guid_block);
1117
1118 for (i = 0; i < total; i++) {
1119 if (!gblock[i].instance_count) {
1120 dev_info(wmi_bus_dev, FW_INFO "%pUL has zero instances\n", &gblock[i].guid);
1121 continue;
1122 }
1123
1124 wblock = kzalloc(sizeof(*wblock), GFP_KERNEL);
1125 if (!wblock)
1126 continue;
1127
1128 wblock->acpi_device = device;
1129 wblock->gblock = gblock[i];
1130 if (gblock[i].flags & ACPI_WMI_EVENT && !event_data_available)
1131 set_bit(WMI_NO_EVENT_DATA, &wblock->flags);
1132
1133 retval = wmi_create_device(wmi_bus_dev, wblock, device);
1134 if (retval) {
1135 kfree(wblock);
1136 continue;
1137 }
1138
1139 list_add_tail(&wblock->list, &wmi_block_list);
1140
1141 retval = wmi_add_device(pdev, &wblock->dev);
1142 if (retval) {
1143 dev_err(wmi_bus_dev, "failed to register %pUL\n",
1144 &wblock->gblock.guid);
1145
1146 list_del(&wblock->list);
1147 put_device(&wblock->dev.dev);
1148 }
1149 }
1150
1151 kfree(obj);
1152
1153 return 0;
1154}
1155
1156/*
1157 * WMI can have EmbeddedControl access regions. In which case, we just want to
1158 * hand these off to the EC driver.
1159 */
1160static acpi_status
1161acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1162 u32 bits, u64 *value,
1163 void *handler_context, void *region_context)
1164{
1165 int result = 0;
1166 u8 temp = 0;
1167
1168 if ((address > 0xFF) || !value)
1169 return AE_BAD_PARAMETER;
1170
1171 if (function != ACPI_READ && function != ACPI_WRITE)
1172 return AE_BAD_PARAMETER;
1173
1174 if (bits != 8)
1175 return AE_BAD_PARAMETER;
1176
1177 if (function == ACPI_READ) {
1178 result = ec_read(address, &temp);
1179 *value = temp;
1180 } else {
1181 temp = 0xff & *value;
1182 result = ec_write(address, temp);
1183 }
1184
1185 switch (result) {
1186 case -EINVAL:
1187 return AE_BAD_PARAMETER;
1188 case -ENODEV:
1189 return AE_NOT_FOUND;
1190 case -ETIME:
1191 return AE_TIME;
1192 default:
1193 return AE_OK;
1194 }
1195}
1196
1197static int wmi_get_notify_data(struct wmi_block *wblock, union acpi_object **obj)
1198{
1199 struct acpi_buffer data = { ACPI_ALLOCATE_BUFFER, NULL };
1200 acpi_status status;
1201
1202 if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags)) {
1203 *obj = NULL;
1204 return 0;
1205 }
1206
1207 status = get_event_data(wblock, &data);
1208 if (ACPI_FAILURE(status)) {
1209 dev_warn(&wblock->dev.dev, "Failed to get event data\n");
1210 return -EIO;
1211 }
1212
1213 *obj = data.pointer;
1214
1215 return 0;
1216}
1217
1218static void wmi_notify_driver(struct wmi_block *wblock, union acpi_object *obj)
1219{
1220 struct wmi_driver *driver = drv_to_wdrv(wblock->dev.dev.driver);
1221
1222 if (!obj && !driver->no_notify_data) {
1223 dev_warn(&wblock->dev.dev, "Event contains no event data\n");
1224 return;
1225 }
1226
1227 if (driver->notify)
1228 driver->notify(&wblock->dev, obj);
1229}
1230
1231static int wmi_notify_device(struct device *dev, void *data)
1232{
1233 struct wmi_block *wblock = dev_to_wblock(dev);
1234 union acpi_object *obj;
1235 u32 *event = data;
1236 int ret;
1237
1238 if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event))
1239 return 0;
1240
1241 down_read(&wblock->notify_lock);
1242 /* The WMI driver notify handler conflicts with the legacy WMI handler.
1243 * Because of this the WMI driver notify handler takes precedence.
1244 */
1245 if (wblock->dev.dev.driver && wblock->driver_ready) {
1246 ret = wmi_get_notify_data(wblock, &obj);
1247 if (ret >= 0) {
1248 wmi_notify_driver(wblock, obj);
1249 kfree(obj);
1250 }
1251 } else {
1252 if (wblock->handler) {
1253 wblock->handler(*event, wblock->handler_data);
1254 } else {
1255 /* The ACPI WMI specification says that _WED should be
1256 * evaluated every time an notification is received, even
1257 * if no consumers are present.
1258 *
1259 * Some firmware implementations actually depend on this
1260 * by using a queue for events which will fill up if the
1261 * WMI driver core stops evaluating _WED due to missing
1262 * WMI event consumers.
1263 *
1264 * Because of this we need this seemingly useless call to
1265 * wmi_get_notify_data() which in turn evaluates _WED.
1266 */
1267 ret = wmi_get_notify_data(wblock, &obj);
1268 if (ret >= 0)
1269 kfree(obj);
1270 }
1271
1272 }
1273 up_read(&wblock->notify_lock);
1274
1275 acpi_bus_generate_netlink_event("wmi", acpi_dev_name(wblock->acpi_device), *event, 0);
1276
1277 return -EBUSY;
1278}
1279
1280static void acpi_wmi_notify_handler(acpi_handle handle, u32 event, void *context)
1281{
1282 struct device *wmi_bus_dev = context;
1283
1284 device_for_each_child(wmi_bus_dev, &event, wmi_notify_device);
1285}
1286
1287static int wmi_remove_device(struct device *dev, void *data)
1288{
1289 struct wmi_block *wblock = dev_to_wblock(dev);
1290
1291 list_del(&wblock->list);
1292 device_unregister(dev);
1293
1294 return 0;
1295}
1296
1297static void acpi_wmi_remove(struct platform_device *device)
1298{
1299 struct device *wmi_bus_device = dev_get_drvdata(&device->dev);
1300
1301 device_for_each_child_reverse(wmi_bus_device, NULL, wmi_remove_device);
1302}
1303
1304static void acpi_wmi_remove_notify_handler(void *data)
1305{
1306 struct acpi_device *acpi_device = data;
1307
1308 acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY, acpi_wmi_notify_handler);
1309}
1310
1311static void acpi_wmi_remove_address_space_handler(void *data)
1312{
1313 struct acpi_device *acpi_device = data;
1314
1315 acpi_remove_address_space_handler(acpi_device->handle, ACPI_ADR_SPACE_EC,
1316 &acpi_wmi_ec_space_handler);
1317}
1318
1319static void acpi_wmi_remove_bus_device(void *data)
1320{
1321 struct device *wmi_bus_dev = data;
1322
1323 device_unregister(wmi_bus_dev);
1324}
1325
1326static int acpi_wmi_probe(struct platform_device *device)
1327{
1328 struct acpi_device *acpi_device;
1329 struct device *wmi_bus_dev;
1330 acpi_status status;
1331 int error;
1332
1333 acpi_device = ACPI_COMPANION(&device->dev);
1334 if (!acpi_device) {
1335 dev_err(&device->dev, "ACPI companion is missing\n");
1336 return -ENODEV;
1337 }
1338
1339 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0), NULL, "wmi_bus-%s",
1340 dev_name(&device->dev));
1341 if (IS_ERR(wmi_bus_dev))
1342 return PTR_ERR(wmi_bus_dev);
1343
1344 error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_bus_device, wmi_bus_dev);
1345 if (error < 0)
1346 return error;
1347
1348 dev_set_drvdata(&device->dev, wmi_bus_dev);
1349
1350 status = acpi_install_address_space_handler(acpi_device->handle,
1351 ACPI_ADR_SPACE_EC,
1352 &acpi_wmi_ec_space_handler,
1353 NULL, NULL);
1354 if (ACPI_FAILURE(status)) {
1355 dev_err(&device->dev, "Error installing EC region handler\n");
1356 return -ENODEV;
1357 }
1358 error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_address_space_handler,
1359 acpi_device);
1360 if (error < 0)
1361 return error;
1362
1363 status = acpi_install_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
1364 acpi_wmi_notify_handler, wmi_bus_dev);
1365 if (ACPI_FAILURE(status)) {
1366 dev_err(&device->dev, "Error installing notify handler\n");
1367 return -ENODEV;
1368 }
1369 error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_notify_handler,
1370 acpi_device);
1371 if (error < 0)
1372 return error;
1373
1374 error = parse_wdg(wmi_bus_dev, device);
1375 if (error) {
1376 dev_err(&device->dev, "Failed to parse _WDG method\n");
1377 return error;
1378 }
1379
1380 return 0;
1381}
1382
1383int __must_check __wmi_driver_register(struct wmi_driver *driver,
1384 struct module *owner)
1385{
1386 driver->driver.owner = owner;
1387 driver->driver.bus = &wmi_bus_type;
1388
1389 return driver_register(&driver->driver);
1390}
1391EXPORT_SYMBOL(__wmi_driver_register);
1392
1393/**
1394 * wmi_driver_unregister() - Unregister a WMI driver
1395 * @driver: WMI driver to unregister
1396 *
1397 * Unregisters a WMI driver from the WMI bus.
1398 */
1399void wmi_driver_unregister(struct wmi_driver *driver)
1400{
1401 driver_unregister(&driver->driver);
1402}
1403EXPORT_SYMBOL(wmi_driver_unregister);
1404
1405static struct platform_driver acpi_wmi_driver = {
1406 .driver = {
1407 .name = "acpi-wmi",
1408 .acpi_match_table = wmi_device_ids,
1409 },
1410 .probe = acpi_wmi_probe,
1411 .remove_new = acpi_wmi_remove,
1412};
1413
1414static int __init acpi_wmi_init(void)
1415{
1416 int error;
1417
1418 if (acpi_disabled)
1419 return -ENODEV;
1420
1421 error = class_register(&wmi_bus_class);
1422 if (error)
1423 return error;
1424
1425 error = bus_register(&wmi_bus_type);
1426 if (error)
1427 goto err_unreg_class;
1428
1429 error = platform_driver_register(&acpi_wmi_driver);
1430 if (error) {
1431 pr_err("Error loading mapper\n");
1432 goto err_unreg_bus;
1433 }
1434
1435 return 0;
1436
1437err_unreg_bus:
1438 bus_unregister(&wmi_bus_type);
1439
1440err_unreg_class:
1441 class_unregister(&wmi_bus_class);
1442
1443 return error;
1444}
1445
1446static void __exit acpi_wmi_exit(void)
1447{
1448 platform_driver_unregister(&acpi_wmi_driver);
1449 bus_unregister(&wmi_bus_type);
1450 class_unregister(&wmi_bus_class);
1451}
1452
1453subsys_initcall_sync(acpi_wmi_init);
1454module_exit(acpi_wmi_exit);