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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 <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// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ACPI-WMI mapping driver
4 *
5 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
6 *
7 * GUID parsing code from ldm.c is:
8 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
9 * Copyright (c) 2001-2007 Anton Altaparmakov
10 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
11 *
12 * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
13 * Copyright (C) 2015 Andrew Lutomirski
14 * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include <linux/acpi.h>
20#include <linux/bits.h>
21#include <linux/build_bug.h>
22#include <linux/device.h>
23#include <linux/init.h>
24#include <linux/kernel.h>
25#include <linux/list.h>
26#include <linux/miscdevice.h>
27#include <linux/module.h>
28#include <linux/platform_device.h>
29#include <linux/slab.h>
30#include <linux/sysfs.h>
31#include <linux/types.h>
32#include <linux/uaccess.h>
33#include <linux/uuid.h>
34#include <linux/wmi.h>
35#include <linux/fs.h>
36#include <uapi/linux/wmi.h>
37
38MODULE_AUTHOR("Carlos Corbacho");
39MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
40MODULE_LICENSE("GPL");
41
42static LIST_HEAD(wmi_block_list);
43
44struct guid_block {
45 guid_t guid;
46 union {
47 char object_id[2];
48 struct {
49 unsigned char notify_id;
50 unsigned char reserved;
51 };
52 };
53 u8 instance_count;
54 u8 flags;
55} __packed;
56static_assert(sizeof(typeof_member(struct guid_block, guid)) == 16);
57static_assert(sizeof(struct guid_block) == 20);
58static_assert(__alignof__(struct guid_block) == 1);
59
60enum { /* wmi_block flags */
61 WMI_READ_TAKES_NO_ARGS,
62 WMI_PROBED,
63};
64
65struct wmi_block {
66 struct wmi_device dev;
67 struct list_head list;
68 struct guid_block gblock;
69 struct miscdevice char_dev;
70 struct mutex char_mutex;
71 struct acpi_device *acpi_device;
72 wmi_notify_handler handler;
73 void *handler_data;
74 u64 req_buf_size;
75 unsigned long flags;
76};
77
78
79/*
80 * If the GUID data block is marked as expensive, we must enable and
81 * explicitily disable data collection.
82 */
83#define ACPI_WMI_EXPENSIVE BIT(0)
84#define ACPI_WMI_METHOD BIT(1) /* GUID is a method */
85#define ACPI_WMI_STRING BIT(2) /* GUID takes & returns a string */
86#define ACPI_WMI_EVENT BIT(3) /* GUID is an event */
87
88static bool debug_event;
89module_param(debug_event, bool, 0444);
90MODULE_PARM_DESC(debug_event,
91 "Log WMI Events [0/1]");
92
93static bool debug_dump_wdg;
94module_param(debug_dump_wdg, bool, 0444);
95MODULE_PARM_DESC(debug_dump_wdg,
96 "Dump available WMI interfaces [0/1]");
97
98static const struct acpi_device_id wmi_device_ids[] = {
99 {"PNP0C14", 0},
100 {"pnp0c14", 0},
101 { }
102};
103MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
104
105/* allow duplicate GUIDs as these device drivers use struct wmi_driver */
106static const char * const allow_duplicates[] = {
107 "05901221-D566-11D1-B2F0-00A0C9062910", /* wmi-bmof */
108 "8A42EA14-4F2A-FD45-6422-0087F7A7E608", /* dell-wmi-ddv */
109 NULL
110};
111
112/*
113 * GUID parsing functions
114 */
115
116static acpi_status find_guid(const char *guid_string, struct wmi_block **out)
117{
118 guid_t guid_input;
119 struct wmi_block *wblock;
120
121 if (!guid_string)
122 return AE_BAD_PARAMETER;
123
124 if (guid_parse(guid_string, &guid_input))
125 return AE_BAD_PARAMETER;
126
127 list_for_each_entry(wblock, &wmi_block_list, list) {
128 if (guid_equal(&wblock->gblock.guid, &guid_input)) {
129 if (out)
130 *out = wblock;
131
132 return AE_OK;
133 }
134 }
135
136 return AE_NOT_FOUND;
137}
138
139static const void *find_guid_context(struct wmi_block *wblock,
140 struct wmi_driver *wdriver)
141{
142 const struct wmi_device_id *id;
143
144 id = wdriver->id_table;
145 if (!id)
146 return NULL;
147
148 while (*id->guid_string) {
149 guid_t guid_input;
150
151 if (guid_parse(id->guid_string, &guid_input))
152 continue;
153 if (guid_equal(&wblock->gblock.guid, &guid_input))
154 return id->context;
155 id++;
156 }
157 return NULL;
158}
159
160static int get_subobj_info(acpi_handle handle, const char *pathname,
161 struct acpi_device_info **info)
162{
163 struct acpi_device_info *dummy_info, **info_ptr;
164 acpi_handle subobj_handle;
165 acpi_status status;
166
167 status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
168 if (status == AE_NOT_FOUND)
169 return -ENOENT;
170 else if (ACPI_FAILURE(status))
171 return -EIO;
172
173 info_ptr = info ? info : &dummy_info;
174 status = acpi_get_object_info(subobj_handle, info_ptr);
175 if (ACPI_FAILURE(status))
176 return -EIO;
177
178 if (!info)
179 kfree(dummy_info);
180
181 return 0;
182}
183
184static acpi_status wmi_method_enable(struct wmi_block *wblock, bool enable)
185{
186 struct guid_block *block;
187 char method[5];
188 acpi_status status;
189 acpi_handle handle;
190
191 block = &wblock->gblock;
192 handle = wblock->acpi_device->handle;
193
194 snprintf(method, 5, "WE%02X", block->notify_id);
195 status = acpi_execute_simple_method(handle, method, enable);
196 if (status == AE_NOT_FOUND)
197 return AE_OK;
198
199 return status;
200}
201
202#define WMI_ACPI_METHOD_NAME_SIZE 5
203
204static inline void get_acpi_method_name(const struct wmi_block *wblock,
205 const char method,
206 char buffer[static WMI_ACPI_METHOD_NAME_SIZE])
207{
208 static_assert(ARRAY_SIZE(wblock->gblock.object_id) == 2);
209 static_assert(WMI_ACPI_METHOD_NAME_SIZE >= 5);
210
211 buffer[0] = 'W';
212 buffer[1] = method;
213 buffer[2] = wblock->gblock.object_id[0];
214 buffer[3] = wblock->gblock.object_id[1];
215 buffer[4] = '\0';
216}
217
218static inline acpi_object_type get_param_acpi_type(const struct wmi_block *wblock)
219{
220 if (wblock->gblock.flags & ACPI_WMI_STRING)
221 return ACPI_TYPE_STRING;
222 else
223 return ACPI_TYPE_BUFFER;
224}
225
226static acpi_status get_event_data(const struct wmi_block *wblock, struct acpi_buffer *out)
227{
228 union acpi_object param = {
229 .integer = {
230 .type = ACPI_TYPE_INTEGER,
231 .value = wblock->gblock.notify_id,
232 }
233 };
234 struct acpi_object_list input = {
235 .count = 1,
236 .pointer = ¶m,
237 };
238
239 return acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, out);
240}
241
242/*
243 * Exported WMI functions
244 */
245
246/**
247 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
248 * @wdev: A wmi bus device from a driver
249 * @length: Required buffer size
250 *
251 * Allocates memory needed for buffer, stores the buffer size in that memory
252 */
253int set_required_buffer_size(struct wmi_device *wdev, u64 length)
254{
255 struct wmi_block *wblock;
256
257 wblock = container_of(wdev, struct wmi_block, dev);
258 wblock->req_buf_size = length;
259
260 return 0;
261}
262EXPORT_SYMBOL_GPL(set_required_buffer_size);
263
264/**
265 * wmi_evaluate_method - Evaluate a WMI method
266 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
267 * @instance: Instance index
268 * @method_id: Method ID to call
269 * @in: Buffer containing input for the method call
270 * @out: Empty buffer to return the method results
271 *
272 * Call an ACPI-WMI method
273 */
274acpi_status wmi_evaluate_method(const char *guid_string, u8 instance, u32 method_id,
275 const struct acpi_buffer *in, struct acpi_buffer *out)
276{
277 struct wmi_block *wblock = NULL;
278 acpi_status status;
279
280 status = find_guid(guid_string, &wblock);
281 if (ACPI_FAILURE(status))
282 return status;
283
284 return wmidev_evaluate_method(&wblock->dev, instance, method_id,
285 in, out);
286}
287EXPORT_SYMBOL_GPL(wmi_evaluate_method);
288
289/**
290 * wmidev_evaluate_method - Evaluate a WMI method
291 * @wdev: A wmi bus device from a driver
292 * @instance: Instance index
293 * @method_id: Method ID to call
294 * @in: Buffer containing input for the method call
295 * @out: Empty buffer to return the method results
296 *
297 * Call an ACPI-WMI method
298 */
299acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance, u32 method_id,
300 const struct acpi_buffer *in, struct acpi_buffer *out)
301{
302 struct guid_block *block;
303 struct wmi_block *wblock;
304 acpi_handle handle;
305 struct acpi_object_list input;
306 union acpi_object params[3];
307 char method[WMI_ACPI_METHOD_NAME_SIZE];
308
309 wblock = container_of(wdev, struct wmi_block, dev);
310 block = &wblock->gblock;
311 handle = wblock->acpi_device->handle;
312
313 if (!(block->flags & ACPI_WMI_METHOD))
314 return AE_BAD_DATA;
315
316 if (block->instance_count <= instance)
317 return AE_BAD_PARAMETER;
318
319 input.count = 2;
320 input.pointer = params;
321 params[0].type = ACPI_TYPE_INTEGER;
322 params[0].integer.value = instance;
323 params[1].type = ACPI_TYPE_INTEGER;
324 params[1].integer.value = method_id;
325
326 if (in) {
327 input.count = 3;
328
329 params[2].type = get_param_acpi_type(wblock);
330 params[2].buffer.length = in->length;
331 params[2].buffer.pointer = in->pointer;
332 }
333
334 get_acpi_method_name(wblock, 'M', method);
335
336 return acpi_evaluate_object(handle, method, &input, out);
337}
338EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
339
340static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
341 struct acpi_buffer *out)
342{
343 struct guid_block *block;
344 acpi_handle handle;
345 acpi_status status, wc_status = AE_ERROR;
346 struct acpi_object_list input;
347 union acpi_object wq_params[1];
348 char wc_method[WMI_ACPI_METHOD_NAME_SIZE];
349 char method[WMI_ACPI_METHOD_NAME_SIZE];
350
351 if (!out)
352 return AE_BAD_PARAMETER;
353
354 block = &wblock->gblock;
355 handle = wblock->acpi_device->handle;
356
357 if (block->instance_count <= instance)
358 return AE_BAD_PARAMETER;
359
360 /* Check GUID is a data block */
361 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
362 return AE_ERROR;
363
364 input.count = 1;
365 input.pointer = wq_params;
366 wq_params[0].type = ACPI_TYPE_INTEGER;
367 wq_params[0].integer.value = instance;
368
369 if (instance == 0 && test_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags))
370 input.count = 0;
371
372 /*
373 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
374 * enable collection.
375 */
376 if (block->flags & ACPI_WMI_EXPENSIVE) {
377 get_acpi_method_name(wblock, 'C', wc_method);
378
379 /*
380 * Some GUIDs break the specification by declaring themselves
381 * expensive, but have no corresponding WCxx method. So we
382 * should not fail if this happens.
383 */
384 wc_status = acpi_execute_simple_method(handle, wc_method, 1);
385 }
386
387 get_acpi_method_name(wblock, 'Q', method);
388 status = acpi_evaluate_object(handle, method, &input, out);
389
390 /*
391 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
392 * the WQxx method failed - we should disable collection anyway.
393 */
394 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
395 /*
396 * Ignore whether this WCxx call succeeds or not since
397 * the previously executed WQxx method call might have
398 * succeeded, and returning the failing status code
399 * of this call would throw away the result of the WQxx
400 * call, potentially leaking memory.
401 */
402 acpi_execute_simple_method(handle, wc_method, 0);
403 }
404
405 return status;
406}
407
408/**
409 * wmi_query_block - Return contents of a WMI block (deprecated)
410 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
411 * @instance: Instance index
412 * @out: Empty buffer to return the contents of the data block to
413 *
414 * Return the contents of an ACPI-WMI data block to a buffer
415 */
416acpi_status wmi_query_block(const char *guid_string, u8 instance,
417 struct acpi_buffer *out)
418{
419 struct wmi_block *wblock;
420 acpi_status status;
421
422 status = find_guid(guid_string, &wblock);
423 if (ACPI_FAILURE(status))
424 return status;
425
426 return __query_block(wblock, instance, out);
427}
428EXPORT_SYMBOL_GPL(wmi_query_block);
429
430union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
431{
432 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
433 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
434
435 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
436 return NULL;
437
438 return out.pointer;
439}
440EXPORT_SYMBOL_GPL(wmidev_block_query);
441
442/**
443 * wmi_set_block - Write to a WMI block
444 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
445 * @instance: Instance index
446 * @in: Buffer containing new values for the data block
447 *
448 * Write the contents of the input buffer to an ACPI-WMI data block
449 */
450acpi_status wmi_set_block(const char *guid_string, u8 instance,
451 const struct acpi_buffer *in)
452{
453 struct wmi_block *wblock = NULL;
454 struct guid_block *block;
455 acpi_handle handle;
456 struct acpi_object_list input;
457 union acpi_object params[2];
458 char method[WMI_ACPI_METHOD_NAME_SIZE];
459 acpi_status status;
460
461 if (!in)
462 return AE_BAD_DATA;
463
464 status = find_guid(guid_string, &wblock);
465 if (ACPI_FAILURE(status))
466 return status;
467
468 block = &wblock->gblock;
469 handle = wblock->acpi_device->handle;
470
471 if (block->instance_count <= instance)
472 return AE_BAD_PARAMETER;
473
474 /* Check GUID is a data block */
475 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
476 return AE_ERROR;
477
478 input.count = 2;
479 input.pointer = params;
480 params[0].type = ACPI_TYPE_INTEGER;
481 params[0].integer.value = instance;
482 params[1].type = get_param_acpi_type(wblock);
483 params[1].buffer.length = in->length;
484 params[1].buffer.pointer = in->pointer;
485
486 get_acpi_method_name(wblock, 'S', method);
487
488 return acpi_evaluate_object(handle, method, &input, NULL);
489}
490EXPORT_SYMBOL_GPL(wmi_set_block);
491
492static void wmi_dump_wdg(const struct guid_block *g)
493{
494 pr_info("%pUL:\n", &g->guid);
495 if (g->flags & ACPI_WMI_EVENT)
496 pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
497 else
498 pr_info("\tobject_id: %2pE\n", g->object_id);
499 pr_info("\tinstance_count: %d\n", g->instance_count);
500 pr_info("\tflags: %#x", g->flags);
501 if (g->flags) {
502 if (g->flags & ACPI_WMI_EXPENSIVE)
503 pr_cont(" ACPI_WMI_EXPENSIVE");
504 if (g->flags & ACPI_WMI_METHOD)
505 pr_cont(" ACPI_WMI_METHOD");
506 if (g->flags & ACPI_WMI_STRING)
507 pr_cont(" ACPI_WMI_STRING");
508 if (g->flags & ACPI_WMI_EVENT)
509 pr_cont(" ACPI_WMI_EVENT");
510 }
511 pr_cont("\n");
512
513}
514
515static void wmi_notify_debug(u32 value, void *context)
516{
517 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
518 union acpi_object *obj;
519 acpi_status status;
520
521 status = wmi_get_event_data(value, &response);
522 if (status != AE_OK) {
523 pr_info("bad event status 0x%x\n", status);
524 return;
525 }
526
527 obj = response.pointer;
528 if (!obj)
529 return;
530
531 pr_info("DEBUG: event 0x%02X ", value);
532 switch (obj->type) {
533 case ACPI_TYPE_BUFFER:
534 pr_cont("BUFFER_TYPE - length %u\n", obj->buffer.length);
535 break;
536 case ACPI_TYPE_STRING:
537 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
538 break;
539 case ACPI_TYPE_INTEGER:
540 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
541 break;
542 case ACPI_TYPE_PACKAGE:
543 pr_cont("PACKAGE_TYPE - %u elements\n", obj->package.count);
544 break;
545 default:
546 pr_cont("object type 0x%X\n", obj->type);
547 }
548 kfree(obj);
549}
550
551/**
552 * wmi_install_notify_handler - Register handler for WMI events
553 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
554 * @handler: Function to handle notifications
555 * @data: Data to be returned to handler when event is fired
556 *
557 * Register a handler for events sent to the ACPI-WMI mapper device.
558 */
559acpi_status wmi_install_notify_handler(const char *guid,
560 wmi_notify_handler handler,
561 void *data)
562{
563 struct wmi_block *block;
564 acpi_status status = AE_NOT_EXIST;
565 guid_t guid_input;
566
567 if (!guid || !handler)
568 return AE_BAD_PARAMETER;
569
570 if (guid_parse(guid, &guid_input))
571 return AE_BAD_PARAMETER;
572
573 list_for_each_entry(block, &wmi_block_list, list) {
574 acpi_status wmi_status;
575
576 if (guid_equal(&block->gblock.guid, &guid_input)) {
577 if (block->handler &&
578 block->handler != wmi_notify_debug)
579 return AE_ALREADY_ACQUIRED;
580
581 block->handler = handler;
582 block->handler_data = data;
583
584 wmi_status = wmi_method_enable(block, true);
585 if ((wmi_status != AE_OK) ||
586 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
587 status = wmi_status;
588 }
589 }
590
591 return status;
592}
593EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
594
595/**
596 * wmi_remove_notify_handler - Unregister handler for WMI events
597 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
598 *
599 * Unregister handler for events sent to the ACPI-WMI mapper device.
600 */
601acpi_status wmi_remove_notify_handler(const char *guid)
602{
603 struct wmi_block *block;
604 acpi_status status = AE_NOT_EXIST;
605 guid_t guid_input;
606
607 if (!guid)
608 return AE_BAD_PARAMETER;
609
610 if (guid_parse(guid, &guid_input))
611 return AE_BAD_PARAMETER;
612
613 list_for_each_entry(block, &wmi_block_list, list) {
614 acpi_status wmi_status;
615
616 if (guid_equal(&block->gblock.guid, &guid_input)) {
617 if (!block->handler ||
618 block->handler == wmi_notify_debug)
619 return AE_NULL_ENTRY;
620
621 if (debug_event) {
622 block->handler = wmi_notify_debug;
623 status = AE_OK;
624 } else {
625 wmi_status = wmi_method_enable(block, false);
626 block->handler = NULL;
627 block->handler_data = NULL;
628 if ((wmi_status != AE_OK) ||
629 ((wmi_status == AE_OK) &&
630 (status == AE_NOT_EXIST)))
631 status = wmi_status;
632 }
633 }
634 }
635
636 return status;
637}
638EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
639
640/**
641 * wmi_get_event_data - Get WMI data associated with an event
642 *
643 * @event: Event to find
644 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
645 *
646 * Returns extra data associated with an event in WMI.
647 */
648acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
649{
650 struct wmi_block *wblock;
651
652 list_for_each_entry(wblock, &wmi_block_list, list) {
653 struct guid_block *gblock = &wblock->gblock;
654
655 if ((gblock->flags & ACPI_WMI_EVENT) && gblock->notify_id == event)
656 return get_event_data(wblock, out);
657 }
658
659 return AE_NOT_FOUND;
660}
661EXPORT_SYMBOL_GPL(wmi_get_event_data);
662
663/**
664 * wmi_has_guid - Check if a GUID is available
665 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
666 *
667 * Check if a given GUID is defined by _WDG
668 */
669bool wmi_has_guid(const char *guid_string)
670{
671 return ACPI_SUCCESS(find_guid(guid_string, NULL));
672}
673EXPORT_SYMBOL_GPL(wmi_has_guid);
674
675/**
676 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
677 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
678 *
679 * Find the _UID of ACPI device associated with this WMI GUID.
680 *
681 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
682 */
683char *wmi_get_acpi_device_uid(const char *guid_string)
684{
685 struct wmi_block *wblock = NULL;
686 acpi_status status;
687
688 status = find_guid(guid_string, &wblock);
689 if (ACPI_FAILURE(status))
690 return NULL;
691
692 return acpi_device_uid(wblock->acpi_device);
693}
694EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
695
696static struct wmi_block *dev_to_wblock(struct device *dev)
697{
698 return container_of(dev, struct wmi_block, dev.dev);
699}
700
701static struct wmi_device *dev_to_wdev(struct device *dev)
702{
703 return container_of(dev, struct wmi_device, dev);
704}
705
706static inline struct wmi_driver *drv_to_wdrv(struct device_driver *drv)
707{
708 return container_of(drv, struct wmi_driver, driver);
709}
710
711/*
712 * sysfs interface
713 */
714static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
715 char *buf)
716{
717 struct wmi_block *wblock = dev_to_wblock(dev);
718
719 return sysfs_emit(buf, "wmi:%pUL\n", &wblock->gblock.guid);
720}
721static DEVICE_ATTR_RO(modalias);
722
723static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
724 char *buf)
725{
726 struct wmi_block *wblock = dev_to_wblock(dev);
727
728 return sysfs_emit(buf, "%pUL\n", &wblock->gblock.guid);
729}
730static DEVICE_ATTR_RO(guid);
731
732static ssize_t instance_count_show(struct device *dev,
733 struct device_attribute *attr, char *buf)
734{
735 struct wmi_block *wblock = dev_to_wblock(dev);
736
737 return sysfs_emit(buf, "%d\n", (int)wblock->gblock.instance_count);
738}
739static DEVICE_ATTR_RO(instance_count);
740
741static ssize_t expensive_show(struct device *dev,
742 struct device_attribute *attr, char *buf)
743{
744 struct wmi_block *wblock = dev_to_wblock(dev);
745
746 return sysfs_emit(buf, "%d\n",
747 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
748}
749static DEVICE_ATTR_RO(expensive);
750
751static struct attribute *wmi_attrs[] = {
752 &dev_attr_modalias.attr,
753 &dev_attr_guid.attr,
754 &dev_attr_instance_count.attr,
755 &dev_attr_expensive.attr,
756 NULL
757};
758ATTRIBUTE_GROUPS(wmi);
759
760static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
761 char *buf)
762{
763 struct wmi_block *wblock = dev_to_wblock(dev);
764
765 return sysfs_emit(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
766}
767static DEVICE_ATTR_RO(notify_id);
768
769static struct attribute *wmi_event_attrs[] = {
770 &dev_attr_notify_id.attr,
771 NULL
772};
773ATTRIBUTE_GROUPS(wmi_event);
774
775static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
776 char *buf)
777{
778 struct wmi_block *wblock = dev_to_wblock(dev);
779
780 return sysfs_emit(buf, "%c%c\n", wblock->gblock.object_id[0],
781 wblock->gblock.object_id[1]);
782}
783static DEVICE_ATTR_RO(object_id);
784
785static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
786 char *buf)
787{
788 struct wmi_device *wdev = dev_to_wdev(dev);
789
790 return sysfs_emit(buf, "%d\n", (int)wdev->setable);
791}
792static DEVICE_ATTR_RO(setable);
793
794static struct attribute *wmi_data_attrs[] = {
795 &dev_attr_object_id.attr,
796 &dev_attr_setable.attr,
797 NULL
798};
799ATTRIBUTE_GROUPS(wmi_data);
800
801static struct attribute *wmi_method_attrs[] = {
802 &dev_attr_object_id.attr,
803 NULL
804};
805ATTRIBUTE_GROUPS(wmi_method);
806
807static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
808{
809 struct wmi_block *wblock = dev_to_wblock(dev);
810
811 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", &wblock->gblock.guid))
812 return -ENOMEM;
813
814 if (add_uevent_var(env, "WMI_GUID=%pUL", &wblock->gblock.guid))
815 return -ENOMEM;
816
817 return 0;
818}
819
820static void wmi_dev_release(struct device *dev)
821{
822 struct wmi_block *wblock = dev_to_wblock(dev);
823
824 kfree(wblock);
825}
826
827static int wmi_dev_match(struct device *dev, struct device_driver *driver)
828{
829 struct wmi_driver *wmi_driver = drv_to_wdrv(driver);
830 struct wmi_block *wblock = dev_to_wblock(dev);
831 const struct wmi_device_id *id = wmi_driver->id_table;
832
833 if (id == NULL)
834 return 0;
835
836 while (*id->guid_string) {
837 guid_t driver_guid;
838
839 if (WARN_ON(guid_parse(id->guid_string, &driver_guid)))
840 continue;
841 if (guid_equal(&driver_guid, &wblock->gblock.guid))
842 return 1;
843
844 id++;
845 }
846
847 return 0;
848}
849static int wmi_char_open(struct inode *inode, struct file *filp)
850{
851 const char *driver_name = filp->f_path.dentry->d_iname;
852 struct wmi_block *wblock;
853 struct wmi_block *next;
854
855 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
856 if (!wblock->dev.dev.driver)
857 continue;
858 if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
859 filp->private_data = wblock;
860 break;
861 }
862 }
863
864 if (!filp->private_data)
865 return -ENODEV;
866
867 return nonseekable_open(inode, filp);
868}
869
870static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
871 size_t length, loff_t *offset)
872{
873 struct wmi_block *wblock = filp->private_data;
874
875 return simple_read_from_buffer(buffer, length, offset,
876 &wblock->req_buf_size,
877 sizeof(wblock->req_buf_size));
878}
879
880static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
881{
882 struct wmi_ioctl_buffer __user *input =
883 (struct wmi_ioctl_buffer __user *) arg;
884 struct wmi_block *wblock = filp->private_data;
885 struct wmi_ioctl_buffer *buf;
886 struct wmi_driver *wdriver;
887 int ret;
888
889 if (_IOC_TYPE(cmd) != WMI_IOC)
890 return -ENOTTY;
891
892 /* make sure we're not calling a higher instance than exists*/
893 if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
894 return -EINVAL;
895
896 mutex_lock(&wblock->char_mutex);
897 buf = wblock->handler_data;
898 if (get_user(buf->length, &input->length)) {
899 dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
900 ret = -EFAULT;
901 goto out_ioctl;
902 }
903 /* if it's too small, abort */
904 if (buf->length < wblock->req_buf_size) {
905 dev_err(&wblock->dev.dev,
906 "Buffer %lld too small, need at least %lld\n",
907 buf->length, wblock->req_buf_size);
908 ret = -EINVAL;
909 goto out_ioctl;
910 }
911 /* if it's too big, warn, driver will only use what is needed */
912 if (buf->length > wblock->req_buf_size)
913 dev_warn(&wblock->dev.dev,
914 "Buffer %lld is bigger than required %lld\n",
915 buf->length, wblock->req_buf_size);
916
917 /* copy the structure from userspace */
918 if (copy_from_user(buf, input, wblock->req_buf_size)) {
919 dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
920 wblock->req_buf_size);
921 ret = -EFAULT;
922 goto out_ioctl;
923 }
924
925 /* let the driver do any filtering and do the call */
926 wdriver = drv_to_wdrv(wblock->dev.dev.driver);
927 if (!try_module_get(wdriver->driver.owner)) {
928 ret = -EBUSY;
929 goto out_ioctl;
930 }
931 ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
932 module_put(wdriver->driver.owner);
933 if (ret)
934 goto out_ioctl;
935
936 /* return the result (only up to our internal buffer size) */
937 if (copy_to_user(input, buf, wblock->req_buf_size)) {
938 dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
939 wblock->req_buf_size);
940 ret = -EFAULT;
941 }
942
943out_ioctl:
944 mutex_unlock(&wblock->char_mutex);
945 return ret;
946}
947
948static const struct file_operations wmi_fops = {
949 .owner = THIS_MODULE,
950 .read = wmi_char_read,
951 .open = wmi_char_open,
952 .unlocked_ioctl = wmi_ioctl,
953 .compat_ioctl = compat_ptr_ioctl,
954};
955
956static int wmi_dev_probe(struct device *dev)
957{
958 struct wmi_block *wblock = dev_to_wblock(dev);
959 struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
960 int ret = 0;
961 char *buf;
962
963 if (ACPI_FAILURE(wmi_method_enable(wblock, true)))
964 dev_warn(dev, "failed to enable device -- probing anyway\n");
965
966 if (wdriver->probe) {
967 ret = wdriver->probe(dev_to_wdev(dev),
968 find_guid_context(wblock, wdriver));
969 if (ret != 0)
970 goto probe_failure;
971 }
972
973 /* driver wants a character device made */
974 if (wdriver->filter_callback) {
975 /* check that required buffer size declared by driver or MOF */
976 if (!wblock->req_buf_size) {
977 dev_err(&wblock->dev.dev,
978 "Required buffer size not set\n");
979 ret = -EINVAL;
980 goto probe_failure;
981 }
982
983 wblock->handler_data = kmalloc(wblock->req_buf_size,
984 GFP_KERNEL);
985 if (!wblock->handler_data) {
986 ret = -ENOMEM;
987 goto probe_failure;
988 }
989
990 buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
991 if (!buf) {
992 ret = -ENOMEM;
993 goto probe_string_failure;
994 }
995 wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
996 wblock->char_dev.name = buf;
997 wblock->char_dev.fops = &wmi_fops;
998 wblock->char_dev.mode = 0444;
999 ret = misc_register(&wblock->char_dev);
1000 if (ret) {
1001 dev_warn(dev, "failed to register char dev: %d\n", ret);
1002 ret = -ENOMEM;
1003 goto probe_misc_failure;
1004 }
1005 }
1006
1007 set_bit(WMI_PROBED, &wblock->flags);
1008 return 0;
1009
1010probe_misc_failure:
1011 kfree(buf);
1012probe_string_failure:
1013 kfree(wblock->handler_data);
1014probe_failure:
1015 if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
1016 dev_warn(dev, "failed to disable device\n");
1017 return ret;
1018}
1019
1020static void wmi_dev_remove(struct device *dev)
1021{
1022 struct wmi_block *wblock = dev_to_wblock(dev);
1023 struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
1024
1025 clear_bit(WMI_PROBED, &wblock->flags);
1026
1027 if (wdriver->filter_callback) {
1028 misc_deregister(&wblock->char_dev);
1029 kfree(wblock->char_dev.name);
1030 kfree(wblock->handler_data);
1031 }
1032
1033 if (wdriver->remove)
1034 wdriver->remove(dev_to_wdev(dev));
1035
1036 if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
1037 dev_warn(dev, "failed to disable device\n");
1038}
1039
1040static struct class wmi_bus_class = {
1041 .name = "wmi_bus",
1042};
1043
1044static struct bus_type wmi_bus_type = {
1045 .name = "wmi",
1046 .dev_groups = wmi_groups,
1047 .match = wmi_dev_match,
1048 .uevent = wmi_dev_uevent,
1049 .probe = wmi_dev_probe,
1050 .remove = wmi_dev_remove,
1051};
1052
1053static const struct device_type wmi_type_event = {
1054 .name = "event",
1055 .groups = wmi_event_groups,
1056 .release = wmi_dev_release,
1057};
1058
1059static const struct device_type wmi_type_method = {
1060 .name = "method",
1061 .groups = wmi_method_groups,
1062 .release = wmi_dev_release,
1063};
1064
1065static const struct device_type wmi_type_data = {
1066 .name = "data",
1067 .groups = wmi_data_groups,
1068 .release = wmi_dev_release,
1069};
1070
1071/*
1072 * _WDG is a static list that is only parsed at startup,
1073 * so it's safe to count entries without extra protection.
1074 */
1075static int guid_count(const guid_t *guid)
1076{
1077 struct wmi_block *wblock;
1078 int count = 0;
1079
1080 list_for_each_entry(wblock, &wmi_block_list, list) {
1081 if (guid_equal(&wblock->gblock.guid, guid))
1082 count++;
1083 }
1084
1085 return count;
1086}
1087
1088static int wmi_create_device(struct device *wmi_bus_dev,
1089 struct wmi_block *wblock,
1090 struct acpi_device *device)
1091{
1092 struct acpi_device_info *info;
1093 char method[WMI_ACPI_METHOD_NAME_SIZE];
1094 int result;
1095 uint count;
1096
1097 if (wblock->gblock.flags & ACPI_WMI_EVENT) {
1098 wblock->dev.dev.type = &wmi_type_event;
1099 goto out_init;
1100 }
1101
1102 if (wblock->gblock.flags & ACPI_WMI_METHOD) {
1103 wblock->dev.dev.type = &wmi_type_method;
1104 mutex_init(&wblock->char_mutex);
1105 goto out_init;
1106 }
1107
1108 /*
1109 * Data Block Query Control Method (WQxx by convention) is
1110 * required per the WMI documentation. If it is not present,
1111 * we ignore this data block.
1112 */
1113 get_acpi_method_name(wblock, 'Q', method);
1114 result = get_subobj_info(device->handle, method, &info);
1115
1116 if (result) {
1117 dev_warn(wmi_bus_dev,
1118 "%s data block query control method not found\n",
1119 method);
1120 return result;
1121 }
1122
1123 wblock->dev.dev.type = &wmi_type_data;
1124
1125 /*
1126 * The Microsoft documentation specifically states:
1127 *
1128 * Data blocks registered with only a single instance
1129 * can ignore the parameter.
1130 *
1131 * ACPICA will get mad at us if we call the method with the wrong number
1132 * of arguments, so check what our method expects. (On some Dell
1133 * laptops, WQxx may not be a method at all.)
1134 */
1135 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1136 set_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags);
1137
1138 kfree(info);
1139
1140 get_acpi_method_name(wblock, 'S', method);
1141 result = get_subobj_info(device->handle, method, NULL);
1142
1143 if (result == 0)
1144 wblock->dev.setable = true;
1145
1146 out_init:
1147 wblock->dev.dev.bus = &wmi_bus_type;
1148 wblock->dev.dev.parent = wmi_bus_dev;
1149
1150 count = guid_count(&wblock->gblock.guid);
1151 if (count)
1152 dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, count);
1153 else
1154 dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid);
1155
1156 device_initialize(&wblock->dev.dev);
1157
1158 return 0;
1159}
1160
1161static void wmi_free_devices(struct acpi_device *device)
1162{
1163 struct wmi_block *wblock, *next;
1164
1165 /* Delete devices for all the GUIDs */
1166 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1167 if (wblock->acpi_device == device) {
1168 list_del(&wblock->list);
1169 device_unregister(&wblock->dev.dev);
1170 }
1171 }
1172}
1173
1174static bool guid_already_parsed_for_legacy(struct acpi_device *device, const guid_t *guid)
1175{
1176 struct wmi_block *wblock;
1177
1178 list_for_each_entry(wblock, &wmi_block_list, list) {
1179 /* skip warning and register if we know the driver will use struct wmi_driver */
1180 for (int i = 0; allow_duplicates[i] != NULL; i++) {
1181 guid_t tmp;
1182
1183 if (guid_parse(allow_duplicates[i], &tmp))
1184 continue;
1185 if (guid_equal(&tmp, guid))
1186 return false;
1187 }
1188 if (guid_equal(&wblock->gblock.guid, guid)) {
1189 /*
1190 * Because we historically didn't track the relationship
1191 * between GUIDs and ACPI nodes, we don't know whether
1192 * we need to suppress GUIDs that are unique on a
1193 * given node but duplicated across nodes.
1194 */
1195 dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1196 guid, dev_name(&wblock->acpi_device->dev));
1197 return true;
1198 }
1199 }
1200
1201 return false;
1202}
1203
1204/*
1205 * Parse the _WDG method for the GUID data blocks
1206 */
1207static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1208{
1209 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
1210 const struct guid_block *gblock;
1211 struct wmi_block *wblock, *next;
1212 union acpi_object *obj;
1213 acpi_status status;
1214 int retval = 0;
1215 u32 i, total;
1216
1217 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1218 if (ACPI_FAILURE(status))
1219 return -ENXIO;
1220
1221 obj = out.pointer;
1222 if (!obj)
1223 return -ENXIO;
1224
1225 if (obj->type != ACPI_TYPE_BUFFER) {
1226 retval = -ENXIO;
1227 goto out_free_pointer;
1228 }
1229
1230 gblock = (const struct guid_block *)obj->buffer.pointer;
1231 total = obj->buffer.length / sizeof(struct guid_block);
1232
1233 for (i = 0; i < total; i++) {
1234 if (debug_dump_wdg)
1235 wmi_dump_wdg(&gblock[i]);
1236
1237 if (guid_already_parsed_for_legacy(device, &gblock[i].guid))
1238 continue;
1239
1240 wblock = kzalloc(sizeof(*wblock), GFP_KERNEL);
1241 if (!wblock) {
1242 retval = -ENOMEM;
1243 break;
1244 }
1245
1246 wblock->acpi_device = device;
1247 wblock->gblock = gblock[i];
1248
1249 retval = wmi_create_device(wmi_bus_dev, wblock, device);
1250 if (retval) {
1251 kfree(wblock);
1252 continue;
1253 }
1254
1255 list_add_tail(&wblock->list, &wmi_block_list);
1256
1257 if (debug_event) {
1258 wblock->handler = wmi_notify_debug;
1259 wmi_method_enable(wblock, true);
1260 }
1261 }
1262
1263 /*
1264 * Now that all of the devices are created, add them to the
1265 * device tree and probe subdrivers.
1266 */
1267 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1268 if (wblock->acpi_device != device)
1269 continue;
1270
1271 retval = device_add(&wblock->dev.dev);
1272 if (retval) {
1273 dev_err(wmi_bus_dev, "failed to register %pUL\n",
1274 &wblock->gblock.guid);
1275 if (debug_event)
1276 wmi_method_enable(wblock, false);
1277 list_del(&wblock->list);
1278 put_device(&wblock->dev.dev);
1279 }
1280 }
1281
1282out_free_pointer:
1283 kfree(out.pointer);
1284 return retval;
1285}
1286
1287/*
1288 * WMI can have EmbeddedControl access regions. In which case, we just want to
1289 * hand these off to the EC driver.
1290 */
1291static acpi_status
1292acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1293 u32 bits, u64 *value,
1294 void *handler_context, void *region_context)
1295{
1296 int result = 0, i = 0;
1297 u8 temp = 0;
1298
1299 if ((address > 0xFF) || !value)
1300 return AE_BAD_PARAMETER;
1301
1302 if (function != ACPI_READ && function != ACPI_WRITE)
1303 return AE_BAD_PARAMETER;
1304
1305 if (bits != 8)
1306 return AE_BAD_PARAMETER;
1307
1308 if (function == ACPI_READ) {
1309 result = ec_read(address, &temp);
1310 (*value) |= ((u64)temp) << i;
1311 } else {
1312 temp = 0xff & ((*value) >> i);
1313 result = ec_write(address, temp);
1314 }
1315
1316 switch (result) {
1317 case -EINVAL:
1318 return AE_BAD_PARAMETER;
1319 case -ENODEV:
1320 return AE_NOT_FOUND;
1321 case -ETIME:
1322 return AE_TIME;
1323 default:
1324 return AE_OK;
1325 }
1326}
1327
1328static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1329 void *context)
1330{
1331 struct wmi_block *wblock = NULL, *iter;
1332
1333 list_for_each_entry(iter, &wmi_block_list, list) {
1334 struct guid_block *block = &iter->gblock;
1335
1336 if (iter->acpi_device->handle == handle &&
1337 (block->flags & ACPI_WMI_EVENT) &&
1338 (block->notify_id == event)) {
1339 wblock = iter;
1340 break;
1341 }
1342 }
1343
1344 if (!wblock)
1345 return;
1346
1347 /* If a driver is bound, then notify the driver. */
1348 if (test_bit(WMI_PROBED, &wblock->flags) && wblock->dev.dev.driver) {
1349 struct wmi_driver *driver = drv_to_wdrv(wblock->dev.dev.driver);
1350 struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1351 acpi_status status;
1352
1353 if (!driver->no_notify_data) {
1354 status = get_event_data(wblock, &evdata);
1355 if (ACPI_FAILURE(status)) {
1356 dev_warn(&wblock->dev.dev, "failed to get event data\n");
1357 return;
1358 }
1359 }
1360
1361 if (driver->notify)
1362 driver->notify(&wblock->dev, evdata.pointer);
1363
1364 kfree(evdata.pointer);
1365 } else if (wblock->handler) {
1366 /* Legacy handler */
1367 wblock->handler(event, wblock->handler_data);
1368 }
1369
1370 if (debug_event)
1371 pr_info("DEBUG: GUID %pUL event 0x%02X\n", &wblock->gblock.guid, event);
1372
1373 acpi_bus_generate_netlink_event(
1374 wblock->acpi_device->pnp.device_class,
1375 dev_name(&wblock->dev.dev),
1376 event, 0);
1377}
1378
1379static int acpi_wmi_remove(struct platform_device *device)
1380{
1381 struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1382
1383 acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
1384 acpi_wmi_notify_handler);
1385 acpi_remove_address_space_handler(acpi_device->handle,
1386 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1387 wmi_free_devices(acpi_device);
1388 device_unregister(dev_get_drvdata(&device->dev));
1389
1390 return 0;
1391}
1392
1393static int acpi_wmi_probe(struct platform_device *device)
1394{
1395 struct acpi_device *acpi_device;
1396 struct device *wmi_bus_dev;
1397 acpi_status status;
1398 int error;
1399
1400 acpi_device = ACPI_COMPANION(&device->dev);
1401 if (!acpi_device) {
1402 dev_err(&device->dev, "ACPI companion is missing\n");
1403 return -ENODEV;
1404 }
1405
1406 status = acpi_install_address_space_handler(acpi_device->handle,
1407 ACPI_ADR_SPACE_EC,
1408 &acpi_wmi_ec_space_handler,
1409 NULL, NULL);
1410 if (ACPI_FAILURE(status)) {
1411 dev_err(&device->dev, "Error installing EC region handler\n");
1412 return -ENODEV;
1413 }
1414
1415 status = acpi_install_notify_handler(acpi_device->handle,
1416 ACPI_ALL_NOTIFY,
1417 acpi_wmi_notify_handler,
1418 NULL);
1419 if (ACPI_FAILURE(status)) {
1420 dev_err(&device->dev, "Error installing notify handler\n");
1421 error = -ENODEV;
1422 goto err_remove_ec_handler;
1423 }
1424
1425 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1426 NULL, "wmi_bus-%s", dev_name(&device->dev));
1427 if (IS_ERR(wmi_bus_dev)) {
1428 error = PTR_ERR(wmi_bus_dev);
1429 goto err_remove_notify_handler;
1430 }
1431 dev_set_drvdata(&device->dev, wmi_bus_dev);
1432
1433 error = parse_wdg(wmi_bus_dev, acpi_device);
1434 if (error) {
1435 pr_err("Failed to parse WDG method\n");
1436 goto err_remove_busdev;
1437 }
1438
1439 return 0;
1440
1441err_remove_busdev:
1442 device_unregister(wmi_bus_dev);
1443
1444err_remove_notify_handler:
1445 acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
1446 acpi_wmi_notify_handler);
1447
1448err_remove_ec_handler:
1449 acpi_remove_address_space_handler(acpi_device->handle,
1450 ACPI_ADR_SPACE_EC,
1451 &acpi_wmi_ec_space_handler);
1452
1453 return error;
1454}
1455
1456int __must_check __wmi_driver_register(struct wmi_driver *driver,
1457 struct module *owner)
1458{
1459 driver->driver.owner = owner;
1460 driver->driver.bus = &wmi_bus_type;
1461
1462 return driver_register(&driver->driver);
1463}
1464EXPORT_SYMBOL(__wmi_driver_register);
1465
1466void wmi_driver_unregister(struct wmi_driver *driver)
1467{
1468 driver_unregister(&driver->driver);
1469}
1470EXPORT_SYMBOL(wmi_driver_unregister);
1471
1472static struct platform_driver acpi_wmi_driver = {
1473 .driver = {
1474 .name = "acpi-wmi",
1475 .acpi_match_table = wmi_device_ids,
1476 },
1477 .probe = acpi_wmi_probe,
1478 .remove = acpi_wmi_remove,
1479};
1480
1481static int __init acpi_wmi_init(void)
1482{
1483 int error;
1484
1485 if (acpi_disabled)
1486 return -ENODEV;
1487
1488 error = class_register(&wmi_bus_class);
1489 if (error)
1490 return error;
1491
1492 error = bus_register(&wmi_bus_type);
1493 if (error)
1494 goto err_unreg_class;
1495
1496 error = platform_driver_register(&acpi_wmi_driver);
1497 if (error) {
1498 pr_err("Error loading mapper\n");
1499 goto err_unreg_bus;
1500 }
1501
1502 return 0;
1503
1504err_unreg_bus:
1505 bus_unregister(&wmi_bus_type);
1506
1507err_unreg_class:
1508 class_unregister(&wmi_bus_class);
1509
1510 return error;
1511}
1512
1513static void __exit acpi_wmi_exit(void)
1514{
1515 platform_driver_unregister(&acpi_wmi_driver);
1516 bus_unregister(&wmi_bus_type);
1517 class_unregister(&wmi_bus_class);
1518}
1519
1520subsys_initcall_sync(acpi_wmi_init);
1521module_exit(acpi_wmi_exit);