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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#include <acpi/acpi_bus.h>
41#include <acpi/acpi_drivers.h>
42
43ACPI_MODULE_NAME("wmi");
44MODULE_AUTHOR("Carlos Corbacho");
45MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
46MODULE_LICENSE("GPL");
47
48#define ACPI_WMI_CLASS "wmi"
49
50static DEFINE_MUTEX(wmi_data_lock);
51static LIST_HEAD(wmi_block_list);
52
53struct guid_block {
54 char guid[16];
55 union {
56 char object_id[2];
57 struct {
58 unsigned char notify_id;
59 unsigned char reserved;
60 };
61 };
62 u8 instance_count;
63 u8 flags;
64};
65
66struct wmi_block {
67 struct list_head list;
68 struct guid_block gblock;
69 acpi_handle handle;
70 wmi_notify_handler handler;
71 void *handler_data;
72 struct device dev;
73};
74
75
76/*
77 * If the GUID data block is marked as expensive, we must enable and
78 * explicitily disable data collection.
79 */
80#define ACPI_WMI_EXPENSIVE 0x1
81#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
82#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
83#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
84
85static bool debug_event;
86module_param(debug_event, bool, 0444);
87MODULE_PARM_DESC(debug_event,
88 "Log WMI Events [0/1]");
89
90static bool debug_dump_wdg;
91module_param(debug_dump_wdg, bool, 0444);
92MODULE_PARM_DESC(debug_dump_wdg,
93 "Dump available WMI interfaces [0/1]");
94
95static int acpi_wmi_remove(struct acpi_device *device, int type);
96static int acpi_wmi_add(struct acpi_device *device);
97static void acpi_wmi_notify(struct acpi_device *device, u32 event);
98
99static const struct acpi_device_id wmi_device_ids[] = {
100 {"PNP0C14", 0},
101 {"pnp0c14", 0},
102 {"", 0},
103};
104MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
105
106static struct acpi_driver acpi_wmi_driver = {
107 .name = "wmi",
108 .class = ACPI_WMI_CLASS,
109 .ids = wmi_device_ids,
110 .ops = {
111 .add = acpi_wmi_add,
112 .remove = acpi_wmi_remove,
113 .notify = acpi_wmi_notify,
114 },
115};
116
117/*
118 * GUID parsing functions
119 */
120
121/**
122 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
123 * @src: Pointer to at least 2 characters to convert.
124 *
125 * Convert a two character ASCII hex string to a number.
126 *
127 * Return: 0-255 Success, the byte was parsed correctly
128 * -1 Error, an invalid character was supplied
129 */
130static int wmi_parse_hexbyte(const u8 *src)
131{
132 int h;
133 int value;
134
135 /* high part */
136 h = value = hex_to_bin(src[0]);
137 if (value < 0)
138 return -1;
139
140 /* low part */
141 value = hex_to_bin(src[1]);
142 if (value >= 0)
143 return (h << 4) | value;
144 return -1;
145}
146
147/**
148 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
149 * @src: Memory block holding binary GUID (16 bytes)
150 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
151 *
152 * Byte swap a binary GUID to match it's real GUID value
153 */
154static void wmi_swap_bytes(u8 *src, u8 *dest)
155{
156 int i;
157
158 for (i = 0; i <= 3; i++)
159 memcpy(dest + i, src + (3 - i), 1);
160
161 for (i = 0; i <= 1; i++)
162 memcpy(dest + 4 + i, src + (5 - i), 1);
163
164 for (i = 0; i <= 1; i++)
165 memcpy(dest + 6 + i, src + (7 - i), 1);
166
167 memcpy(dest + 8, src + 8, 8);
168}
169
170/**
171 * wmi_parse_guid - Convert GUID from ASCII to binary
172 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
173 * @dest: Memory block to hold binary GUID (16 bytes)
174 *
175 * N.B. The GUID need not be NULL terminated.
176 *
177 * Return: 'true' @dest contains binary GUID
178 * 'false' @dest contents are undefined
179 */
180static bool wmi_parse_guid(const u8 *src, u8 *dest)
181{
182 static const int size[] = { 4, 2, 2, 2, 6 };
183 int i, j, v;
184
185 if (src[8] != '-' || src[13] != '-' ||
186 src[18] != '-' || src[23] != '-')
187 return false;
188
189 for (j = 0; j < 5; j++, src++) {
190 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
191 v = wmi_parse_hexbyte(src);
192 if (v < 0)
193 return false;
194 }
195 }
196
197 return true;
198}
199
200/*
201 * Convert a raw GUID to the ACII string representation
202 */
203static int wmi_gtoa(const char *in, char *out)
204{
205 int i;
206
207 for (i = 3; i >= 0; i--)
208 out += sprintf(out, "%02X", in[i] & 0xFF);
209
210 out += sprintf(out, "-");
211 out += sprintf(out, "%02X", in[5] & 0xFF);
212 out += sprintf(out, "%02X", in[4] & 0xFF);
213 out += sprintf(out, "-");
214 out += sprintf(out, "%02X", in[7] & 0xFF);
215 out += sprintf(out, "%02X", in[6] & 0xFF);
216 out += sprintf(out, "-");
217 out += sprintf(out, "%02X", in[8] & 0xFF);
218 out += sprintf(out, "%02X", in[9] & 0xFF);
219 out += sprintf(out, "-");
220
221 for (i = 10; i <= 15; i++)
222 out += sprintf(out, "%02X", in[i] & 0xFF);
223
224 *out = '\0';
225 return 0;
226}
227
228static bool find_guid(const char *guid_string, struct wmi_block **out)
229{
230 char tmp[16], guid_input[16];
231 struct wmi_block *wblock;
232 struct guid_block *block;
233 struct list_head *p;
234
235 wmi_parse_guid(guid_string, tmp);
236 wmi_swap_bytes(tmp, guid_input);
237
238 list_for_each(p, &wmi_block_list) {
239 wblock = list_entry(p, struct wmi_block, list);
240 block = &wblock->gblock;
241
242 if (memcmp(block->guid, guid_input, 16) == 0) {
243 if (out)
244 *out = wblock;
245 return 1;
246 }
247 }
248 return 0;
249}
250
251static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
252{
253 struct guid_block *block = NULL;
254 char method[5];
255 struct acpi_object_list input;
256 union acpi_object params[1];
257 acpi_status status;
258 acpi_handle handle;
259
260 block = &wblock->gblock;
261 handle = wblock->handle;
262
263 if (!block)
264 return AE_NOT_EXIST;
265
266 input.count = 1;
267 input.pointer = params;
268 params[0].type = ACPI_TYPE_INTEGER;
269 params[0].integer.value = enable;
270
271 snprintf(method, 5, "WE%02X", block->notify_id);
272 status = acpi_evaluate_object(handle, method, &input, NULL);
273
274 if (status != AE_OK && status != AE_NOT_FOUND)
275 return status;
276 else
277 return AE_OK;
278}
279
280/*
281 * Exported WMI functions
282 */
283/**
284 * wmi_evaluate_method - Evaluate a WMI method
285 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
286 * @instance: Instance index
287 * @method_id: Method ID to call
288 * &in: Buffer containing input for the method call
289 * &out: Empty buffer to return the method results
290 *
291 * Call an ACPI-WMI method
292 */
293acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
294u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
295{
296 struct guid_block *block = NULL;
297 struct wmi_block *wblock = NULL;
298 acpi_handle handle;
299 acpi_status status;
300 struct acpi_object_list input;
301 union acpi_object params[3];
302 char method[5] = "WM";
303
304 if (!find_guid(guid_string, &wblock))
305 return AE_ERROR;
306
307 block = &wblock->gblock;
308 handle = wblock->handle;
309
310 if (!(block->flags & ACPI_WMI_METHOD))
311 return AE_BAD_DATA;
312
313 if (block->instance_count < instance)
314 return AE_BAD_PARAMETER;
315
316 input.count = 2;
317 input.pointer = params;
318 params[0].type = ACPI_TYPE_INTEGER;
319 params[0].integer.value = instance;
320 params[1].type = ACPI_TYPE_INTEGER;
321 params[1].integer.value = method_id;
322
323 if (in) {
324 input.count = 3;
325
326 if (block->flags & ACPI_WMI_STRING) {
327 params[2].type = ACPI_TYPE_STRING;
328 } else {
329 params[2].type = ACPI_TYPE_BUFFER;
330 }
331 params[2].buffer.length = in->length;
332 params[2].buffer.pointer = in->pointer;
333 }
334
335 strncat(method, block->object_id, 2);
336
337 status = acpi_evaluate_object(handle, method, &input, out);
338
339 return status;
340}
341EXPORT_SYMBOL_GPL(wmi_evaluate_method);
342
343/**
344 * wmi_query_block - Return contents of a WMI block
345 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
346 * @instance: Instance index
347 * &out: Empty buffer to return the contents of the data block to
348 *
349 * Return the contents of an ACPI-WMI data block to a buffer
350 */
351acpi_status wmi_query_block(const char *guid_string, u8 instance,
352struct acpi_buffer *out)
353{
354 struct guid_block *block = NULL;
355 struct wmi_block *wblock = NULL;
356 acpi_handle handle, wc_handle;
357 acpi_status status, wc_status = AE_ERROR;
358 struct acpi_object_list input, wc_input;
359 union acpi_object wc_params[1], wq_params[1];
360 char method[5];
361 char wc_method[5] = "WC";
362
363 if (!guid_string || !out)
364 return AE_BAD_PARAMETER;
365
366 if (!find_guid(guid_string, &wblock))
367 return AE_ERROR;
368
369 block = &wblock->gblock;
370 handle = wblock->handle;
371
372 if (block->instance_count < instance)
373 return AE_BAD_PARAMETER;
374
375 /* Check GUID is a data block */
376 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
377 return AE_ERROR;
378
379 input.count = 1;
380 input.pointer = wq_params;
381 wq_params[0].type = ACPI_TYPE_INTEGER;
382 wq_params[0].integer.value = instance;
383
384 /*
385 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
386 * enable collection.
387 */
388 if (block->flags & ACPI_WMI_EXPENSIVE) {
389 wc_input.count = 1;
390 wc_input.pointer = wc_params;
391 wc_params[0].type = ACPI_TYPE_INTEGER;
392 wc_params[0].integer.value = 1;
393
394 strncat(wc_method, block->object_id, 2);
395
396 /*
397 * Some GUIDs break the specification by declaring themselves
398 * expensive, but have no corresponding WCxx method. So we
399 * should not fail if this happens.
400 */
401 wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
402 if (ACPI_SUCCESS(wc_status))
403 wc_status = acpi_evaluate_object(handle, wc_method,
404 &wc_input, NULL);
405 }
406
407 strcpy(method, "WQ");
408 strncat(method, block->object_id, 2);
409
410 status = acpi_evaluate_object(handle, method, &input, out);
411
412 /*
413 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
414 * the WQxx method failed - we should disable collection anyway.
415 */
416 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
417 wc_params[0].integer.value = 0;
418 status = acpi_evaluate_object(handle,
419 wc_method, &wc_input, NULL);
420 }
421
422 return status;
423}
424EXPORT_SYMBOL_GPL(wmi_query_block);
425
426/**
427 * wmi_set_block - Write to a WMI block
428 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
429 * @instance: Instance index
430 * &in: Buffer containing new values for the data block
431 *
432 * Write the contents of the input buffer to an ACPI-WMI data block
433 */
434acpi_status wmi_set_block(const char *guid_string, u8 instance,
435const struct acpi_buffer *in)
436{
437 struct guid_block *block = NULL;
438 struct wmi_block *wblock = NULL;
439 acpi_handle handle;
440 struct acpi_object_list input;
441 union acpi_object params[2];
442 char method[5] = "WS";
443
444 if (!guid_string || !in)
445 return AE_BAD_DATA;
446
447 if (!find_guid(guid_string, &wblock))
448 return AE_ERROR;
449
450 block = &wblock->gblock;
451 handle = wblock->handle;
452
453 if (block->instance_count < instance)
454 return AE_BAD_PARAMETER;
455
456 /* Check GUID is a data block */
457 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
458 return AE_ERROR;
459
460 input.count = 2;
461 input.pointer = params;
462 params[0].type = ACPI_TYPE_INTEGER;
463 params[0].integer.value = instance;
464
465 if (block->flags & ACPI_WMI_STRING) {
466 params[1].type = ACPI_TYPE_STRING;
467 } else {
468 params[1].type = ACPI_TYPE_BUFFER;
469 }
470 params[1].buffer.length = in->length;
471 params[1].buffer.pointer = in->pointer;
472
473 strncat(method, block->object_id, 2);
474
475 return acpi_evaluate_object(handle, method, &input, NULL);
476}
477EXPORT_SYMBOL_GPL(wmi_set_block);
478
479static void wmi_dump_wdg(const struct guid_block *g)
480{
481 char guid_string[37];
482
483 wmi_gtoa(g->guid, guid_string);
484
485 pr_info("%s:\n", guid_string);
486 pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
487 pr_info("\tnotify_id: %02X\n", g->notify_id);
488 pr_info("\treserved: %02X\n", g->reserved);
489 pr_info("\tinstance_count: %d\n", g->instance_count);
490 pr_info("\tflags: %#x", g->flags);
491 if (g->flags) {
492 if (g->flags & ACPI_WMI_EXPENSIVE)
493 pr_cont(" ACPI_WMI_EXPENSIVE");
494 if (g->flags & ACPI_WMI_METHOD)
495 pr_cont(" ACPI_WMI_METHOD");
496 if (g->flags & ACPI_WMI_STRING)
497 pr_cont(" ACPI_WMI_STRING");
498 if (g->flags & ACPI_WMI_EVENT)
499 pr_cont(" ACPI_WMI_EVENT");
500 }
501 pr_cont("\n");
502
503}
504
505static void wmi_notify_debug(u32 value, void *context)
506{
507 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
508 union acpi_object *obj;
509 acpi_status status;
510
511 status = wmi_get_event_data(value, &response);
512 if (status != AE_OK) {
513 pr_info("bad event status 0x%x\n", status);
514 return;
515 }
516
517 obj = (union acpi_object *)response.pointer;
518
519 if (!obj)
520 return;
521
522 pr_info("DEBUG Event ");
523 switch(obj->type) {
524 case ACPI_TYPE_BUFFER:
525 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
526 break;
527 case ACPI_TYPE_STRING:
528 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
529 break;
530 case ACPI_TYPE_INTEGER:
531 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
532 break;
533 case ACPI_TYPE_PACKAGE:
534 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
535 break;
536 default:
537 pr_cont("object type 0x%X\n", obj->type);
538 }
539 kfree(obj);
540}
541
542/**
543 * wmi_install_notify_handler - Register handler for WMI events
544 * @handler: Function to handle notifications
545 * @data: Data to be returned to handler when event is fired
546 *
547 * Register a handler for events sent to the ACPI-WMI mapper device.
548 */
549acpi_status wmi_install_notify_handler(const char *guid,
550wmi_notify_handler handler, void *data)
551{
552 struct wmi_block *block;
553 acpi_status status = AE_NOT_EXIST;
554 char tmp[16], guid_input[16];
555 struct list_head *p;
556
557 if (!guid || !handler)
558 return AE_BAD_PARAMETER;
559
560 wmi_parse_guid(guid, tmp);
561 wmi_swap_bytes(tmp, guid_input);
562
563 list_for_each(p, &wmi_block_list) {
564 acpi_status wmi_status;
565 block = list_entry(p, struct wmi_block, list);
566
567 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
568 if (block->handler &&
569 block->handler != wmi_notify_debug)
570 return AE_ALREADY_ACQUIRED;
571
572 block->handler = handler;
573 block->handler_data = data;
574
575 wmi_status = wmi_method_enable(block, 1);
576 if ((wmi_status != AE_OK) ||
577 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
578 status = wmi_status;
579 }
580 }
581
582 return status;
583}
584EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
585
586/**
587 * wmi_uninstall_notify_handler - Unregister handler for WMI events
588 *
589 * Unregister handler for events sent to the ACPI-WMI mapper device.
590 */
591acpi_status wmi_remove_notify_handler(const char *guid)
592{
593 struct wmi_block *block;
594 acpi_status status = AE_NOT_EXIST;
595 char tmp[16], guid_input[16];
596 struct list_head *p;
597
598 if (!guid)
599 return AE_BAD_PARAMETER;
600
601 wmi_parse_guid(guid, tmp);
602 wmi_swap_bytes(tmp, guid_input);
603
604 list_for_each(p, &wmi_block_list) {
605 acpi_status wmi_status;
606 block = list_entry(p, struct wmi_block, list);
607
608 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
609 if (!block->handler ||
610 block->handler == wmi_notify_debug)
611 return AE_NULL_ENTRY;
612
613 if (debug_event) {
614 block->handler = wmi_notify_debug;
615 status = AE_OK;
616 } else {
617 wmi_status = wmi_method_enable(block, 0);
618 block->handler = NULL;
619 block->handler_data = NULL;
620 if ((wmi_status != AE_OK) ||
621 ((wmi_status == AE_OK) &&
622 (status == AE_NOT_EXIST)))
623 status = wmi_status;
624 }
625 }
626 }
627
628 return status;
629}
630EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
631
632/**
633 * wmi_get_event_data - Get WMI data associated with an event
634 *
635 * @event: Event to find
636 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
637 *
638 * Returns extra data associated with an event in WMI.
639 */
640acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
641{
642 struct acpi_object_list input;
643 union acpi_object params[1];
644 struct guid_block *gblock;
645 struct wmi_block *wblock;
646 struct list_head *p;
647
648 input.count = 1;
649 input.pointer = params;
650 params[0].type = ACPI_TYPE_INTEGER;
651 params[0].integer.value = event;
652
653 list_for_each(p, &wmi_block_list) {
654 wblock = list_entry(p, struct wmi_block, list);
655 gblock = &wblock->gblock;
656
657 if ((gblock->flags & ACPI_WMI_EVENT) &&
658 (gblock->notify_id == event))
659 return acpi_evaluate_object(wblock->handle, "_WED",
660 &input, out);
661 }
662
663 return AE_NOT_FOUND;
664}
665EXPORT_SYMBOL_GPL(wmi_get_event_data);
666
667/**
668 * wmi_has_guid - Check if a GUID is available
669 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
670 *
671 * Check if a given GUID is defined by _WDG
672 */
673bool wmi_has_guid(const char *guid_string)
674{
675 return find_guid(guid_string, NULL);
676}
677EXPORT_SYMBOL_GPL(wmi_has_guid);
678
679/*
680 * sysfs interface
681 */
682static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
683 char *buf)
684{
685 char guid_string[37];
686 struct wmi_block *wblock;
687
688 wblock = dev_get_drvdata(dev);
689 if (!wblock)
690 return -ENOMEM;
691
692 wmi_gtoa(wblock->gblock.guid, guid_string);
693
694 return sprintf(buf, "wmi:%s\n", guid_string);
695}
696
697static struct device_attribute wmi_dev_attrs[] = {
698 __ATTR_RO(modalias),
699 __ATTR_NULL
700};
701
702static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
703{
704 char guid_string[37];
705
706 struct wmi_block *wblock;
707
708 if (add_uevent_var(env, "MODALIAS="))
709 return -ENOMEM;
710
711 wblock = dev_get_drvdata(dev);
712 if (!wblock)
713 return -ENOMEM;
714
715 wmi_gtoa(wblock->gblock.guid, guid_string);
716
717 strcpy(&env->buf[env->buflen - 1], "wmi:");
718 memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
719 env->buflen += 40;
720
721 return 0;
722}
723
724static void wmi_dev_free(struct device *dev)
725{
726 struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
727
728 kfree(wmi_block);
729}
730
731static struct class wmi_class = {
732 .name = "wmi",
733 .dev_release = wmi_dev_free,
734 .dev_uevent = wmi_dev_uevent,
735 .dev_attrs = wmi_dev_attrs,
736};
737
738static int wmi_create_device(const struct guid_block *gblock,
739 struct wmi_block *wblock, acpi_handle handle)
740{
741 char guid_string[37];
742
743 wblock->dev.class = &wmi_class;
744
745 wmi_gtoa(gblock->guid, guid_string);
746 dev_set_name(&wblock->dev, guid_string);
747
748 dev_set_drvdata(&wblock->dev, wblock);
749
750 return device_register(&wblock->dev);
751}
752
753static void wmi_free_devices(void)
754{
755 struct wmi_block *wblock, *next;
756
757 /* Delete devices for all the GUIDs */
758 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
759 list_del(&wblock->list);
760 if (wblock->dev.class)
761 device_unregister(&wblock->dev);
762 else
763 kfree(wblock);
764 }
765}
766
767static bool guid_already_parsed(const char *guid_string)
768{
769 struct wmi_block *wblock;
770
771 list_for_each_entry(wblock, &wmi_block_list, list)
772 if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
773 return true;
774
775 return false;
776}
777
778/*
779 * Parse the _WDG method for the GUID data blocks
780 */
781static acpi_status parse_wdg(acpi_handle handle)
782{
783 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
784 union acpi_object *obj;
785 const struct guid_block *gblock;
786 struct wmi_block *wblock;
787 acpi_status status;
788 int retval;
789 u32 i, total;
790
791 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
792 if (ACPI_FAILURE(status))
793 return -ENXIO;
794
795 obj = (union acpi_object *) out.pointer;
796 if (!obj)
797 return -ENXIO;
798
799 if (obj->type != ACPI_TYPE_BUFFER) {
800 retval = -ENXIO;
801 goto out_free_pointer;
802 }
803
804 gblock = (const struct guid_block *)obj->buffer.pointer;
805 total = obj->buffer.length / sizeof(struct guid_block);
806
807 for (i = 0; i < total; i++) {
808 if (debug_dump_wdg)
809 wmi_dump_wdg(&gblock[i]);
810
811 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
812 if (!wblock)
813 return AE_NO_MEMORY;
814
815 wblock->handle = handle;
816 wblock->gblock = gblock[i];
817
818 /*
819 Some WMI devices, like those for nVidia hooks, have a
820 duplicate GUID. It's not clear what we should do in this
821 case yet, so for now, we'll just ignore the duplicate
822 for device creation.
823 */
824 if (!guid_already_parsed(gblock[i].guid)) {
825 retval = wmi_create_device(&gblock[i], wblock, handle);
826 if (retval) {
827 wmi_free_devices();
828 goto out_free_pointer;
829 }
830 }
831
832 list_add_tail(&wblock->list, &wmi_block_list);
833
834 if (debug_event) {
835 wblock->handler = wmi_notify_debug;
836 wmi_method_enable(wblock, 1);
837 }
838 }
839
840 retval = 0;
841
842out_free_pointer:
843 kfree(out.pointer);
844
845 return retval;
846}
847
848/*
849 * WMI can have EmbeddedControl access regions. In which case, we just want to
850 * hand these off to the EC driver.
851 */
852static acpi_status
853acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
854 u32 bits, u64 *value,
855 void *handler_context, void *region_context)
856{
857 int result = 0, i = 0;
858 u8 temp = 0;
859
860 if ((address > 0xFF) || !value)
861 return AE_BAD_PARAMETER;
862
863 if (function != ACPI_READ && function != ACPI_WRITE)
864 return AE_BAD_PARAMETER;
865
866 if (bits != 8)
867 return AE_BAD_PARAMETER;
868
869 if (function == ACPI_READ) {
870 result = ec_read(address, &temp);
871 (*value) |= ((u64)temp) << i;
872 } else {
873 temp = 0xff & ((*value) >> i);
874 result = ec_write(address, temp);
875 }
876
877 switch (result) {
878 case -EINVAL:
879 return AE_BAD_PARAMETER;
880 break;
881 case -ENODEV:
882 return AE_NOT_FOUND;
883 break;
884 case -ETIME:
885 return AE_TIME;
886 break;
887 default:
888 return AE_OK;
889 }
890}
891
892static void acpi_wmi_notify(struct acpi_device *device, u32 event)
893{
894 struct guid_block *block;
895 struct wmi_block *wblock;
896 struct list_head *p;
897 char guid_string[37];
898
899 list_for_each(p, &wmi_block_list) {
900 wblock = list_entry(p, struct wmi_block, list);
901 block = &wblock->gblock;
902
903 if ((block->flags & ACPI_WMI_EVENT) &&
904 (block->notify_id == event)) {
905 if (wblock->handler)
906 wblock->handler(event, wblock->handler_data);
907 if (debug_event) {
908 wmi_gtoa(wblock->gblock.guid, guid_string);
909 pr_info("DEBUG Event GUID: %s\n", guid_string);
910 }
911
912 acpi_bus_generate_netlink_event(
913 device->pnp.device_class, dev_name(&device->dev),
914 event, 0);
915 break;
916 }
917 }
918}
919
920static int acpi_wmi_remove(struct acpi_device *device, int type)
921{
922 acpi_remove_address_space_handler(device->handle,
923 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
924 wmi_free_devices();
925
926 return 0;
927}
928
929static int acpi_wmi_add(struct acpi_device *device)
930{
931 acpi_status status;
932 int error;
933
934 status = acpi_install_address_space_handler(device->handle,
935 ACPI_ADR_SPACE_EC,
936 &acpi_wmi_ec_space_handler,
937 NULL, NULL);
938 if (ACPI_FAILURE(status)) {
939 pr_err("Error installing EC region handler\n");
940 return -ENODEV;
941 }
942
943 error = parse_wdg(device->handle);
944 if (error) {
945 acpi_remove_address_space_handler(device->handle,
946 ACPI_ADR_SPACE_EC,
947 &acpi_wmi_ec_space_handler);
948 pr_err("Failed to parse WDG method\n");
949 return error;
950 }
951
952 return 0;
953}
954
955static int __init acpi_wmi_init(void)
956{
957 int error;
958
959 if (acpi_disabled)
960 return -ENODEV;
961
962 error = class_register(&wmi_class);
963 if (error)
964 return error;
965
966 error = acpi_bus_register_driver(&acpi_wmi_driver);
967 if (error) {
968 pr_err("Error loading mapper\n");
969 class_unregister(&wmi_class);
970 return error;
971 }
972
973 pr_info("Mapper loaded\n");
974 return 0;
975}
976
977static void __exit acpi_wmi_exit(void)
978{
979 acpi_bus_unregister_driver(&acpi_wmi_driver);
980 class_unregister(&wmi_class);
981
982 pr_info("Mapper unloaded\n");
983}
984
985subsys_initcall(acpi_wmi_init);
986module_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);