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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/*
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#include <linux/uuid.h>
41
42ACPI_MODULE_NAME("wmi");
43MODULE_AUTHOR("Carlos Corbacho");
44MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
45MODULE_LICENSE("GPL");
46
47#define ACPI_WMI_CLASS "wmi"
48
49static LIST_HEAD(wmi_block_list);
50
51struct guid_block {
52 char guid[16];
53 union {
54 char object_id[2];
55 struct {
56 unsigned char notify_id;
57 unsigned char reserved;
58 };
59 };
60 u8 instance_count;
61 u8 flags;
62};
63
64struct wmi_block {
65 struct list_head list;
66 struct guid_block gblock;
67 acpi_handle handle;
68 wmi_notify_handler handler;
69 void *handler_data;
70 struct device dev;
71};
72
73
74/*
75 * If the GUID data block is marked as expensive, we must enable and
76 * explicitily disable data collection.
77 */
78#define ACPI_WMI_EXPENSIVE 0x1
79#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
80#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
81#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
82
83static bool debug_event;
84module_param(debug_event, bool, 0444);
85MODULE_PARM_DESC(debug_event,
86 "Log WMI Events [0/1]");
87
88static bool debug_dump_wdg;
89module_param(debug_dump_wdg, bool, 0444);
90MODULE_PARM_DESC(debug_dump_wdg,
91 "Dump available WMI interfaces [0/1]");
92
93static int acpi_wmi_remove(struct acpi_device *device);
94static int acpi_wmi_add(struct acpi_device *device);
95static void acpi_wmi_notify(struct acpi_device *device, u32 event);
96
97static const struct acpi_device_id wmi_device_ids[] = {
98 {"PNP0C14", 0},
99 {"pnp0c14", 0},
100 {"", 0},
101};
102MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
103
104static struct acpi_driver acpi_wmi_driver = {
105 .name = "wmi",
106 .class = ACPI_WMI_CLASS,
107 .ids = wmi_device_ids,
108 .ops = {
109 .add = acpi_wmi_add,
110 .remove = acpi_wmi_remove,
111 .notify = acpi_wmi_notify,
112 },
113};
114
115/*
116 * GUID parsing functions
117 */
118
119static bool find_guid(const char *guid_string, struct wmi_block **out)
120{
121 uuid_le guid_input;
122 struct wmi_block *wblock;
123 struct guid_block *block;
124 struct list_head *p;
125
126 if (uuid_le_to_bin(guid_string, &guid_input))
127 return false;
128
129 list_for_each(p, &wmi_block_list) {
130 wblock = list_entry(p, struct wmi_block, list);
131 block = &wblock->gblock;
132
133 if (memcmp(block->guid, &guid_input, 16) == 0) {
134 if (out)
135 *out = wblock;
136 return true;
137 }
138 }
139 return false;
140}
141
142static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
143{
144 struct guid_block *block = NULL;
145 char method[5];
146 acpi_status status;
147 acpi_handle handle;
148
149 block = &wblock->gblock;
150 handle = wblock->handle;
151
152 snprintf(method, 5, "WE%02X", block->notify_id);
153 status = acpi_execute_simple_method(handle, method, enable);
154
155 if (status != AE_OK && status != AE_NOT_FOUND)
156 return status;
157 else
158 return AE_OK;
159}
160
161/*
162 * Exported WMI functions
163 */
164/**
165 * wmi_evaluate_method - Evaluate a WMI method
166 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
167 * @instance: Instance index
168 * @method_id: Method ID to call
169 * &in: Buffer containing input for the method call
170 * &out: Empty buffer to return the method results
171 *
172 * Call an ACPI-WMI method
173 */
174acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
175u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
176{
177 struct guid_block *block = NULL;
178 struct wmi_block *wblock = NULL;
179 acpi_handle handle;
180 acpi_status status;
181 struct acpi_object_list input;
182 union acpi_object params[3];
183 char method[5] = "WM";
184
185 if (!find_guid(guid_string, &wblock))
186 return AE_ERROR;
187
188 block = &wblock->gblock;
189 handle = wblock->handle;
190
191 if (!(block->flags & ACPI_WMI_METHOD))
192 return AE_BAD_DATA;
193
194 if (block->instance_count < instance)
195 return AE_BAD_PARAMETER;
196
197 input.count = 2;
198 input.pointer = params;
199 params[0].type = ACPI_TYPE_INTEGER;
200 params[0].integer.value = instance;
201 params[1].type = ACPI_TYPE_INTEGER;
202 params[1].integer.value = method_id;
203
204 if (in) {
205 input.count = 3;
206
207 if (block->flags & ACPI_WMI_STRING) {
208 params[2].type = ACPI_TYPE_STRING;
209 } else {
210 params[2].type = ACPI_TYPE_BUFFER;
211 }
212 params[2].buffer.length = in->length;
213 params[2].buffer.pointer = in->pointer;
214 }
215
216 strncat(method, block->object_id, 2);
217
218 status = acpi_evaluate_object(handle, method, &input, out);
219
220 return status;
221}
222EXPORT_SYMBOL_GPL(wmi_evaluate_method);
223
224/**
225 * wmi_query_block - Return contents of a WMI block
226 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
227 * @instance: Instance index
228 * &out: Empty buffer to return the contents of the data block to
229 *
230 * Return the contents of an ACPI-WMI data block to a buffer
231 */
232acpi_status wmi_query_block(const char *guid_string, u8 instance,
233struct acpi_buffer *out)
234{
235 struct guid_block *block = NULL;
236 struct wmi_block *wblock = NULL;
237 acpi_handle handle;
238 acpi_status status, wc_status = AE_ERROR;
239 struct acpi_object_list input;
240 union acpi_object wq_params[1];
241 char method[5];
242 char wc_method[5] = "WC";
243
244 if (!guid_string || !out)
245 return AE_BAD_PARAMETER;
246
247 if (!find_guid(guid_string, &wblock))
248 return AE_ERROR;
249
250 block = &wblock->gblock;
251 handle = wblock->handle;
252
253 if (block->instance_count < instance)
254 return AE_BAD_PARAMETER;
255
256 /* Check GUID is a data block */
257 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
258 return AE_ERROR;
259
260 input.count = 1;
261 input.pointer = wq_params;
262 wq_params[0].type = ACPI_TYPE_INTEGER;
263 wq_params[0].integer.value = instance;
264
265 /*
266 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
267 * enable collection.
268 */
269 if (block->flags & ACPI_WMI_EXPENSIVE) {
270 strncat(wc_method, block->object_id, 2);
271
272 /*
273 * Some GUIDs break the specification by declaring themselves
274 * expensive, but have no corresponding WCxx method. So we
275 * should not fail if this happens.
276 */
277 if (acpi_has_method(handle, wc_method))
278 wc_status = acpi_execute_simple_method(handle,
279 wc_method, 1);
280 }
281
282 strcpy(method, "WQ");
283 strncat(method, block->object_id, 2);
284
285 status = acpi_evaluate_object(handle, method, &input, out);
286
287 /*
288 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
289 * the WQxx method failed - we should disable collection anyway.
290 */
291 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
292 status = acpi_execute_simple_method(handle, wc_method, 0);
293 }
294
295 return status;
296}
297EXPORT_SYMBOL_GPL(wmi_query_block);
298
299/**
300 * wmi_set_block - Write to a WMI block
301 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
302 * @instance: Instance index
303 * &in: Buffer containing new values for the data block
304 *
305 * Write the contents of the input buffer to an ACPI-WMI data block
306 */
307acpi_status wmi_set_block(const char *guid_string, u8 instance,
308const struct acpi_buffer *in)
309{
310 struct guid_block *block = NULL;
311 struct wmi_block *wblock = NULL;
312 acpi_handle handle;
313 struct acpi_object_list input;
314 union acpi_object params[2];
315 char method[5] = "WS";
316
317 if (!guid_string || !in)
318 return AE_BAD_DATA;
319
320 if (!find_guid(guid_string, &wblock))
321 return AE_ERROR;
322
323 block = &wblock->gblock;
324 handle = wblock->handle;
325
326 if (block->instance_count < instance)
327 return AE_BAD_PARAMETER;
328
329 /* Check GUID is a data block */
330 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
331 return AE_ERROR;
332
333 input.count = 2;
334 input.pointer = params;
335 params[0].type = ACPI_TYPE_INTEGER;
336 params[0].integer.value = instance;
337
338 if (block->flags & ACPI_WMI_STRING) {
339 params[1].type = ACPI_TYPE_STRING;
340 } else {
341 params[1].type = ACPI_TYPE_BUFFER;
342 }
343 params[1].buffer.length = in->length;
344 params[1].buffer.pointer = in->pointer;
345
346 strncat(method, block->object_id, 2);
347
348 return acpi_evaluate_object(handle, method, &input, NULL);
349}
350EXPORT_SYMBOL_GPL(wmi_set_block);
351
352static void wmi_dump_wdg(const struct guid_block *g)
353{
354 pr_info("%pUL:\n", g->guid);
355 pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
356 pr_info("\tnotify_id: %02X\n", g->notify_id);
357 pr_info("\treserved: %02X\n", g->reserved);
358 pr_info("\tinstance_count: %d\n", g->instance_count);
359 pr_info("\tflags: %#x", g->flags);
360 if (g->flags) {
361 if (g->flags & ACPI_WMI_EXPENSIVE)
362 pr_cont(" ACPI_WMI_EXPENSIVE");
363 if (g->flags & ACPI_WMI_METHOD)
364 pr_cont(" ACPI_WMI_METHOD");
365 if (g->flags & ACPI_WMI_STRING)
366 pr_cont(" ACPI_WMI_STRING");
367 if (g->flags & ACPI_WMI_EVENT)
368 pr_cont(" ACPI_WMI_EVENT");
369 }
370 pr_cont("\n");
371
372}
373
374static void wmi_notify_debug(u32 value, void *context)
375{
376 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
377 union acpi_object *obj;
378 acpi_status status;
379
380 status = wmi_get_event_data(value, &response);
381 if (status != AE_OK) {
382 pr_info("bad event status 0x%x\n", status);
383 return;
384 }
385
386 obj = (union acpi_object *)response.pointer;
387
388 if (!obj)
389 return;
390
391 pr_info("DEBUG Event ");
392 switch(obj->type) {
393 case ACPI_TYPE_BUFFER:
394 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
395 break;
396 case ACPI_TYPE_STRING:
397 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
398 break;
399 case ACPI_TYPE_INTEGER:
400 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
401 break;
402 case ACPI_TYPE_PACKAGE:
403 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
404 break;
405 default:
406 pr_cont("object type 0x%X\n", obj->type);
407 }
408 kfree(obj);
409}
410
411/**
412 * wmi_install_notify_handler - Register handler for WMI events
413 * @handler: Function to handle notifications
414 * @data: Data to be returned to handler when event is fired
415 *
416 * Register a handler for events sent to the ACPI-WMI mapper device.
417 */
418acpi_status wmi_install_notify_handler(const char *guid,
419wmi_notify_handler handler, void *data)
420{
421 struct wmi_block *block;
422 acpi_status status = AE_NOT_EXIST;
423 uuid_le guid_input;
424 struct list_head *p;
425
426 if (!guid || !handler)
427 return AE_BAD_PARAMETER;
428
429 if (uuid_le_to_bin(guid, &guid_input))
430 return AE_BAD_PARAMETER;
431
432 list_for_each(p, &wmi_block_list) {
433 acpi_status wmi_status;
434 block = list_entry(p, struct wmi_block, list);
435
436 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
437 if (block->handler &&
438 block->handler != wmi_notify_debug)
439 return AE_ALREADY_ACQUIRED;
440
441 block->handler = handler;
442 block->handler_data = data;
443
444 wmi_status = wmi_method_enable(block, 1);
445 if ((wmi_status != AE_OK) ||
446 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
447 status = wmi_status;
448 }
449 }
450
451 return status;
452}
453EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
454
455/**
456 * wmi_uninstall_notify_handler - Unregister handler for WMI events
457 *
458 * Unregister handler for events sent to the ACPI-WMI mapper device.
459 */
460acpi_status wmi_remove_notify_handler(const char *guid)
461{
462 struct wmi_block *block;
463 acpi_status status = AE_NOT_EXIST;
464 uuid_le guid_input;
465 struct list_head *p;
466
467 if (!guid)
468 return AE_BAD_PARAMETER;
469
470 if (uuid_le_to_bin(guid, &guid_input))
471 return AE_BAD_PARAMETER;
472
473 list_for_each(p, &wmi_block_list) {
474 acpi_status wmi_status;
475 block = list_entry(p, struct wmi_block, list);
476
477 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
478 if (!block->handler ||
479 block->handler == wmi_notify_debug)
480 return AE_NULL_ENTRY;
481
482 if (debug_event) {
483 block->handler = wmi_notify_debug;
484 status = AE_OK;
485 } else {
486 wmi_status = wmi_method_enable(block, 0);
487 block->handler = NULL;
488 block->handler_data = NULL;
489 if ((wmi_status != AE_OK) ||
490 ((wmi_status == AE_OK) &&
491 (status == AE_NOT_EXIST)))
492 status = wmi_status;
493 }
494 }
495 }
496
497 return status;
498}
499EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
500
501/**
502 * wmi_get_event_data - Get WMI data associated with an event
503 *
504 * @event: Event to find
505 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
506 *
507 * Returns extra data associated with an event in WMI.
508 */
509acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
510{
511 struct acpi_object_list input;
512 union acpi_object params[1];
513 struct guid_block *gblock;
514 struct wmi_block *wblock;
515 struct list_head *p;
516
517 input.count = 1;
518 input.pointer = params;
519 params[0].type = ACPI_TYPE_INTEGER;
520 params[0].integer.value = event;
521
522 list_for_each(p, &wmi_block_list) {
523 wblock = list_entry(p, struct wmi_block, list);
524 gblock = &wblock->gblock;
525
526 if ((gblock->flags & ACPI_WMI_EVENT) &&
527 (gblock->notify_id == event))
528 return acpi_evaluate_object(wblock->handle, "_WED",
529 &input, out);
530 }
531
532 return AE_NOT_FOUND;
533}
534EXPORT_SYMBOL_GPL(wmi_get_event_data);
535
536/**
537 * wmi_has_guid - Check if a GUID is available
538 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
539 *
540 * Check if a given GUID is defined by _WDG
541 */
542bool wmi_has_guid(const char *guid_string)
543{
544 return find_guid(guid_string, NULL);
545}
546EXPORT_SYMBOL_GPL(wmi_has_guid);
547
548/*
549 * sysfs interface
550 */
551static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
552 char *buf)
553{
554 struct wmi_block *wblock;
555
556 wblock = dev_get_drvdata(dev);
557 if (!wblock) {
558 strcat(buf, "\n");
559 return strlen(buf);
560 }
561
562 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
563}
564static DEVICE_ATTR_RO(modalias);
565
566static struct attribute *wmi_attrs[] = {
567 &dev_attr_modalias.attr,
568 NULL,
569};
570ATTRIBUTE_GROUPS(wmi);
571
572static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
573{
574 char guid_string[37];
575
576 struct wmi_block *wblock;
577
578 if (add_uevent_var(env, "MODALIAS="))
579 return -ENOMEM;
580
581 wblock = dev_get_drvdata(dev);
582 if (!wblock)
583 return -ENOMEM;
584
585 sprintf(guid_string, "%pUL", wblock->gblock.guid);
586
587 strcpy(&env->buf[env->buflen - 1], "wmi:");
588 memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
589 env->buflen += 40;
590
591 return 0;
592}
593
594static void wmi_dev_free(struct device *dev)
595{
596 struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
597
598 kfree(wmi_block);
599}
600
601static struct class wmi_class = {
602 .name = "wmi",
603 .dev_release = wmi_dev_free,
604 .dev_uevent = wmi_dev_uevent,
605 .dev_groups = wmi_groups,
606};
607
608static int wmi_create_device(const struct guid_block *gblock,
609 struct wmi_block *wblock, acpi_handle handle)
610{
611 wblock->dev.class = &wmi_class;
612
613 dev_set_name(&wblock->dev, "%pUL", gblock->guid);
614
615 dev_set_drvdata(&wblock->dev, wblock);
616
617 return device_register(&wblock->dev);
618}
619
620static void wmi_free_devices(void)
621{
622 struct wmi_block *wblock, *next;
623
624 /* Delete devices for all the GUIDs */
625 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
626 list_del(&wblock->list);
627 if (wblock->dev.class)
628 device_unregister(&wblock->dev);
629 else
630 kfree(wblock);
631 }
632}
633
634static bool guid_already_parsed(const char *guid_string)
635{
636 struct wmi_block *wblock;
637
638 list_for_each_entry(wblock, &wmi_block_list, list)
639 if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
640 return true;
641
642 return false;
643}
644
645/*
646 * Parse the _WDG method for the GUID data blocks
647 */
648static int parse_wdg(acpi_handle handle)
649{
650 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
651 union acpi_object *obj;
652 const struct guid_block *gblock;
653 struct wmi_block *wblock;
654 acpi_status status;
655 int retval;
656 u32 i, total;
657
658 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
659 if (ACPI_FAILURE(status))
660 return -ENXIO;
661
662 obj = (union acpi_object *) out.pointer;
663 if (!obj)
664 return -ENXIO;
665
666 if (obj->type != ACPI_TYPE_BUFFER) {
667 retval = -ENXIO;
668 goto out_free_pointer;
669 }
670
671 gblock = (const struct guid_block *)obj->buffer.pointer;
672 total = obj->buffer.length / sizeof(struct guid_block);
673
674 for (i = 0; i < total; i++) {
675 if (debug_dump_wdg)
676 wmi_dump_wdg(&gblock[i]);
677
678 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
679 if (!wblock)
680 return -ENOMEM;
681
682 wblock->handle = handle;
683 wblock->gblock = gblock[i];
684
685 /*
686 Some WMI devices, like those for nVidia hooks, have a
687 duplicate GUID. It's not clear what we should do in this
688 case yet, so for now, we'll just ignore the duplicate
689 for device creation.
690 */
691 if (!guid_already_parsed(gblock[i].guid)) {
692 retval = wmi_create_device(&gblock[i], wblock, handle);
693 if (retval) {
694 wmi_free_devices();
695 goto out_free_pointer;
696 }
697 }
698
699 list_add_tail(&wblock->list, &wmi_block_list);
700
701 if (debug_event) {
702 wblock->handler = wmi_notify_debug;
703 wmi_method_enable(wblock, 1);
704 }
705 }
706
707 retval = 0;
708
709out_free_pointer:
710 kfree(out.pointer);
711
712 return retval;
713}
714
715/*
716 * WMI can have EmbeddedControl access regions. In which case, we just want to
717 * hand these off to the EC driver.
718 */
719static acpi_status
720acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
721 u32 bits, u64 *value,
722 void *handler_context, void *region_context)
723{
724 int result = 0, i = 0;
725 u8 temp = 0;
726
727 if ((address > 0xFF) || !value)
728 return AE_BAD_PARAMETER;
729
730 if (function != ACPI_READ && function != ACPI_WRITE)
731 return AE_BAD_PARAMETER;
732
733 if (bits != 8)
734 return AE_BAD_PARAMETER;
735
736 if (function == ACPI_READ) {
737 result = ec_read(address, &temp);
738 (*value) |= ((u64)temp) << i;
739 } else {
740 temp = 0xff & ((*value) >> i);
741 result = ec_write(address, temp);
742 }
743
744 switch (result) {
745 case -EINVAL:
746 return AE_BAD_PARAMETER;
747 break;
748 case -ENODEV:
749 return AE_NOT_FOUND;
750 break;
751 case -ETIME:
752 return AE_TIME;
753 break;
754 default:
755 return AE_OK;
756 }
757}
758
759static void acpi_wmi_notify(struct acpi_device *device, u32 event)
760{
761 struct guid_block *block;
762 struct wmi_block *wblock;
763 struct list_head *p;
764
765 list_for_each(p, &wmi_block_list) {
766 wblock = list_entry(p, struct wmi_block, list);
767 block = &wblock->gblock;
768
769 if ((block->flags & ACPI_WMI_EVENT) &&
770 (block->notify_id == event)) {
771 if (wblock->handler)
772 wblock->handler(event, wblock->handler_data);
773 if (debug_event) {
774 pr_info("DEBUG Event GUID: %pUL\n",
775 wblock->gblock.guid);
776 }
777
778 acpi_bus_generate_netlink_event(
779 device->pnp.device_class, dev_name(&device->dev),
780 event, 0);
781 break;
782 }
783 }
784}
785
786static int acpi_wmi_remove(struct acpi_device *device)
787{
788 acpi_remove_address_space_handler(device->handle,
789 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
790 wmi_free_devices();
791
792 return 0;
793}
794
795static int acpi_wmi_add(struct acpi_device *device)
796{
797 acpi_status status;
798 int error;
799
800 status = acpi_install_address_space_handler(device->handle,
801 ACPI_ADR_SPACE_EC,
802 &acpi_wmi_ec_space_handler,
803 NULL, NULL);
804 if (ACPI_FAILURE(status)) {
805 pr_err("Error installing EC region handler\n");
806 return -ENODEV;
807 }
808
809 error = parse_wdg(device->handle);
810 if (error) {
811 acpi_remove_address_space_handler(device->handle,
812 ACPI_ADR_SPACE_EC,
813 &acpi_wmi_ec_space_handler);
814 pr_err("Failed to parse WDG method\n");
815 return error;
816 }
817
818 return 0;
819}
820
821static int __init acpi_wmi_init(void)
822{
823 int error;
824
825 if (acpi_disabled)
826 return -ENODEV;
827
828 error = class_register(&wmi_class);
829 if (error)
830 return error;
831
832 error = acpi_bus_register_driver(&acpi_wmi_driver);
833 if (error) {
834 pr_err("Error loading mapper\n");
835 class_unregister(&wmi_class);
836 return error;
837 }
838
839 pr_info("Mapper loaded\n");
840 return 0;
841}
842
843static void __exit acpi_wmi_exit(void)
844{
845 acpi_bus_unregister_driver(&acpi_wmi_driver);
846 class_unregister(&wmi_class);
847
848 pr_info("Mapper unloaded\n");
849}
850
851subsys_initcall(acpi_wmi_init);
852module_exit(acpi_wmi_exit);