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