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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);
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/device.h>
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/list.h>
24#include <linux/miscdevice.h>
25#include <linux/module.h>
26#include <linux/platform_device.h>
27#include <linux/slab.h>
28#include <linux/types.h>
29#include <linux/uaccess.h>
30#include <linux/uuid.h>
31#include <linux/wmi.h>
32#include <linux/fs.h>
33#include <uapi/linux/wmi.h>
34
35ACPI_MODULE_NAME("wmi");
36MODULE_AUTHOR("Carlos Corbacho");
37MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
38MODULE_LICENSE("GPL");
39
40static LIST_HEAD(wmi_block_list);
41
42struct guid_block {
43 char guid[16];
44 union {
45 char object_id[2];
46 struct {
47 unsigned char notify_id;
48 unsigned char reserved;
49 };
50 };
51 u8 instance_count;
52 u8 flags;
53};
54
55struct wmi_block {
56 struct wmi_device dev;
57 struct list_head list;
58 struct guid_block gblock;
59 struct miscdevice char_dev;
60 struct mutex char_mutex;
61 struct acpi_device *acpi_device;
62 wmi_notify_handler handler;
63 void *handler_data;
64 u64 req_buf_size;
65
66 bool read_takes_no_args;
67};
68
69
70/*
71 * If the GUID data block is marked as expensive, we must enable and
72 * explicitily disable data collection.
73 */
74#define ACPI_WMI_EXPENSIVE 0x1
75#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
76#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
77#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
78
79static bool debug_event;
80module_param(debug_event, bool, 0444);
81MODULE_PARM_DESC(debug_event,
82 "Log WMI Events [0/1]");
83
84static bool debug_dump_wdg;
85module_param(debug_dump_wdg, bool, 0444);
86MODULE_PARM_DESC(debug_dump_wdg,
87 "Dump available WMI interfaces [0/1]");
88
89static int acpi_wmi_remove(struct platform_device *device);
90static int acpi_wmi_probe(struct platform_device *device);
91
92static const struct acpi_device_id wmi_device_ids[] = {
93 {"PNP0C14", 0},
94 {"pnp0c14", 0},
95 {"", 0},
96};
97MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
98
99static struct platform_driver acpi_wmi_driver = {
100 .driver = {
101 .name = "acpi-wmi",
102 .acpi_match_table = wmi_device_ids,
103 },
104 .probe = acpi_wmi_probe,
105 .remove = acpi_wmi_remove,
106};
107
108/*
109 * GUID parsing functions
110 */
111
112static bool find_guid(const char *guid_string, struct wmi_block **out)
113{
114 guid_t guid_input;
115 struct wmi_block *wblock;
116 struct guid_block *block;
117
118 if (guid_parse(guid_string, &guid_input))
119 return false;
120
121 list_for_each_entry(wblock, &wmi_block_list, list) {
122 block = &wblock->gblock;
123
124 if (memcmp(block->guid, &guid_input, 16) == 0) {
125 if (out)
126 *out = wblock;
127 return true;
128 }
129 }
130 return false;
131}
132
133static const void *find_guid_context(struct wmi_block *wblock,
134 struct wmi_driver *wdriver)
135{
136 const struct wmi_device_id *id;
137 guid_t guid_input;
138
139 if (wblock == NULL || wdriver == NULL)
140 return NULL;
141 if (wdriver->id_table == NULL)
142 return NULL;
143
144 id = wdriver->id_table;
145 while (*id->guid_string) {
146 if (guid_parse(id->guid_string, &guid_input))
147 continue;
148 if (!memcmp(wblock->gblock.guid, &guid_input, 16))
149 return id->context;
150 id++;
151 }
152 return NULL;
153}
154
155static int get_subobj_info(acpi_handle handle, const char *pathname,
156 struct acpi_device_info **info)
157{
158 struct acpi_device_info *dummy_info, **info_ptr;
159 acpi_handle subobj_handle;
160 acpi_status status;
161
162 status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
163 if (status == AE_NOT_FOUND)
164 return -ENOENT;
165 else if (ACPI_FAILURE(status))
166 return -EIO;
167
168 info_ptr = info ? info : &dummy_info;
169 status = acpi_get_object_info(subobj_handle, info_ptr);
170 if (ACPI_FAILURE(status))
171 return -EIO;
172
173 if (!info)
174 kfree(dummy_info);
175
176 return 0;
177}
178
179static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
180{
181 struct guid_block *block = NULL;
182 char method[5];
183 acpi_status status;
184 acpi_handle handle;
185
186 block = &wblock->gblock;
187 handle = wblock->acpi_device->handle;
188
189 snprintf(method, 5, "WE%02X", block->notify_id);
190 status = acpi_execute_simple_method(handle, method, enable);
191
192 if (status != AE_OK && status != AE_NOT_FOUND)
193 return status;
194 else
195 return AE_OK;
196}
197
198/*
199 * Exported WMI functions
200 */
201
202/**
203 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
204 * @wdev: A wmi bus device from a driver
205 * @length: Required buffer size
206 *
207 * Allocates memory needed for buffer, stores the buffer size in that memory
208 */
209int set_required_buffer_size(struct wmi_device *wdev, u64 length)
210{
211 struct wmi_block *wblock;
212
213 wblock = container_of(wdev, struct wmi_block, dev);
214 wblock->req_buf_size = length;
215
216 return 0;
217}
218EXPORT_SYMBOL_GPL(set_required_buffer_size);
219
220/**
221 * wmi_evaluate_method - Evaluate a WMI method
222 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
223 * @instance: Instance index
224 * @method_id: Method ID to call
225 * @in: Buffer containing input for the method call
226 * @out: Empty buffer to return the method results
227 *
228 * Call an ACPI-WMI method
229 */
230acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
231u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
232{
233 struct wmi_block *wblock = NULL;
234
235 if (!find_guid(guid_string, &wblock))
236 return AE_ERROR;
237 return wmidev_evaluate_method(&wblock->dev, instance, method_id,
238 in, out);
239}
240EXPORT_SYMBOL_GPL(wmi_evaluate_method);
241
242/**
243 * wmidev_evaluate_method - Evaluate a WMI method
244 * @wdev: A wmi bus device from a driver
245 * @instance: Instance index
246 * @method_id: Method ID to call
247 * @in: Buffer containing input for the method call
248 * @out: Empty buffer to return the method results
249 *
250 * Call an ACPI-WMI method
251 */
252acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
253 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
254{
255 struct guid_block *block = NULL;
256 struct wmi_block *wblock = NULL;
257 acpi_handle handle;
258 acpi_status status;
259 struct acpi_object_list input;
260 union acpi_object params[3];
261 char method[5] = "WM";
262
263 wblock = container_of(wdev, struct wmi_block, dev);
264 block = &wblock->gblock;
265 handle = wblock->acpi_device->handle;
266
267 if (!(block->flags & ACPI_WMI_METHOD))
268 return AE_BAD_DATA;
269
270 if (block->instance_count <= instance)
271 return AE_BAD_PARAMETER;
272
273 input.count = 2;
274 input.pointer = params;
275 params[0].type = ACPI_TYPE_INTEGER;
276 params[0].integer.value = instance;
277 params[1].type = ACPI_TYPE_INTEGER;
278 params[1].integer.value = method_id;
279
280 if (in) {
281 input.count = 3;
282
283 if (block->flags & ACPI_WMI_STRING) {
284 params[2].type = ACPI_TYPE_STRING;
285 } else {
286 params[2].type = ACPI_TYPE_BUFFER;
287 }
288 params[2].buffer.length = in->length;
289 params[2].buffer.pointer = in->pointer;
290 }
291
292 strncat(method, block->object_id, 2);
293
294 status = acpi_evaluate_object(handle, method, &input, out);
295
296 return status;
297}
298EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
299
300static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
301 struct acpi_buffer *out)
302{
303 struct guid_block *block = NULL;
304 acpi_handle handle;
305 acpi_status status, wc_status = AE_ERROR;
306 struct acpi_object_list input;
307 union acpi_object wq_params[1];
308 char method[5];
309 char wc_method[5] = "WC";
310
311 if (!out)
312 return AE_BAD_PARAMETER;
313
314 block = &wblock->gblock;
315 handle = wblock->acpi_device->handle;
316
317 if (block->instance_count <= instance)
318 return AE_BAD_PARAMETER;
319
320 /* Check GUID is a data block */
321 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
322 return AE_ERROR;
323
324 input.count = 1;
325 input.pointer = wq_params;
326 wq_params[0].type = ACPI_TYPE_INTEGER;
327 wq_params[0].integer.value = instance;
328
329 if (instance == 0 && wblock->read_takes_no_args)
330 input.count = 0;
331
332 /*
333 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
334 * enable collection.
335 */
336 if (block->flags & ACPI_WMI_EXPENSIVE) {
337 strncat(wc_method, block->object_id, 2);
338
339 /*
340 * Some GUIDs break the specification by declaring themselves
341 * expensive, but have no corresponding WCxx method. So we
342 * should not fail if this happens.
343 */
344 wc_status = acpi_execute_simple_method(handle, wc_method, 1);
345 }
346
347 strcpy(method, "WQ");
348 strncat(method, block->object_id, 2);
349
350 status = acpi_evaluate_object(handle, method, &input, out);
351
352 /*
353 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
354 * the WQxx method failed - we should disable collection anyway.
355 */
356 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
357 status = acpi_execute_simple_method(handle, wc_method, 0);
358 }
359
360 return status;
361}
362
363/**
364 * wmi_query_block - Return contents of a WMI block (deprecated)
365 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
366 * @instance: Instance index
367 * @out: Empty buffer to return the contents of the data block to
368 *
369 * Return the contents of an ACPI-WMI data block to a buffer
370 */
371acpi_status wmi_query_block(const char *guid_string, u8 instance,
372 struct acpi_buffer *out)
373{
374 struct wmi_block *wblock;
375
376 if (!guid_string)
377 return AE_BAD_PARAMETER;
378
379 if (!find_guid(guid_string, &wblock))
380 return AE_ERROR;
381
382 return __query_block(wblock, instance, out);
383}
384EXPORT_SYMBOL_GPL(wmi_query_block);
385
386union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
387{
388 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
389 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
390
391 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
392 return NULL;
393
394 return (union acpi_object *)out.pointer;
395}
396EXPORT_SYMBOL_GPL(wmidev_block_query);
397
398/**
399 * wmi_set_block - Write to a WMI block
400 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
401 * @instance: Instance index
402 * @in: Buffer containing new values for the data block
403 *
404 * Write the contents of the input buffer to an ACPI-WMI data block
405 */
406acpi_status wmi_set_block(const char *guid_string, u8 instance,
407 const struct acpi_buffer *in)
408{
409 struct guid_block *block = NULL;
410 struct wmi_block *wblock = NULL;
411 acpi_handle handle;
412 struct acpi_object_list input;
413 union acpi_object params[2];
414 char method[5] = "WS";
415
416 if (!guid_string || !in)
417 return AE_BAD_DATA;
418
419 if (!find_guid(guid_string, &wblock))
420 return AE_ERROR;
421
422 block = &wblock->gblock;
423 handle = wblock->acpi_device->handle;
424
425 if (block->instance_count <= instance)
426 return AE_BAD_PARAMETER;
427
428 /* Check GUID is a data block */
429 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
430 return AE_ERROR;
431
432 input.count = 2;
433 input.pointer = params;
434 params[0].type = ACPI_TYPE_INTEGER;
435 params[0].integer.value = instance;
436
437 if (block->flags & ACPI_WMI_STRING) {
438 params[1].type = ACPI_TYPE_STRING;
439 } else {
440 params[1].type = ACPI_TYPE_BUFFER;
441 }
442 params[1].buffer.length = in->length;
443 params[1].buffer.pointer = in->pointer;
444
445 strncat(method, block->object_id, 2);
446
447 return acpi_evaluate_object(handle, method, &input, NULL);
448}
449EXPORT_SYMBOL_GPL(wmi_set_block);
450
451static void wmi_dump_wdg(const struct guid_block *g)
452{
453 pr_info("%pUL:\n", g->guid);
454 if (g->flags & ACPI_WMI_EVENT)
455 pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
456 else
457 pr_info("\tobject_id: %2pE\n", g->object_id);
458 pr_info("\tinstance_count: %d\n", g->instance_count);
459 pr_info("\tflags: %#x", g->flags);
460 if (g->flags) {
461 if (g->flags & ACPI_WMI_EXPENSIVE)
462 pr_cont(" ACPI_WMI_EXPENSIVE");
463 if (g->flags & ACPI_WMI_METHOD)
464 pr_cont(" ACPI_WMI_METHOD");
465 if (g->flags & ACPI_WMI_STRING)
466 pr_cont(" ACPI_WMI_STRING");
467 if (g->flags & ACPI_WMI_EVENT)
468 pr_cont(" ACPI_WMI_EVENT");
469 }
470 pr_cont("\n");
471
472}
473
474static void wmi_notify_debug(u32 value, void *context)
475{
476 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
477 union acpi_object *obj;
478 acpi_status status;
479
480 status = wmi_get_event_data(value, &response);
481 if (status != AE_OK) {
482 pr_info("bad event status 0x%x\n", status);
483 return;
484 }
485
486 obj = (union acpi_object *)response.pointer;
487
488 if (!obj)
489 return;
490
491 pr_info("DEBUG Event ");
492 switch(obj->type) {
493 case ACPI_TYPE_BUFFER:
494 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
495 break;
496 case ACPI_TYPE_STRING:
497 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
498 break;
499 case ACPI_TYPE_INTEGER:
500 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
501 break;
502 case ACPI_TYPE_PACKAGE:
503 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
504 break;
505 default:
506 pr_cont("object type 0x%X\n", obj->type);
507 }
508 kfree(obj);
509}
510
511/**
512 * wmi_install_notify_handler - Register handler for WMI events
513 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
514 * @handler: Function to handle notifications
515 * @data: Data to be returned to handler when event is fired
516 *
517 * Register a handler for events sent to the ACPI-WMI mapper device.
518 */
519acpi_status wmi_install_notify_handler(const char *guid,
520wmi_notify_handler handler, void *data)
521{
522 struct wmi_block *block;
523 acpi_status status = AE_NOT_EXIST;
524 guid_t guid_input;
525
526 if (!guid || !handler)
527 return AE_BAD_PARAMETER;
528
529 if (guid_parse(guid, &guid_input))
530 return AE_BAD_PARAMETER;
531
532 list_for_each_entry(block, &wmi_block_list, list) {
533 acpi_status wmi_status;
534
535 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
536 if (block->handler &&
537 block->handler != wmi_notify_debug)
538 return AE_ALREADY_ACQUIRED;
539
540 block->handler = handler;
541 block->handler_data = data;
542
543 wmi_status = wmi_method_enable(block, 1);
544 if ((wmi_status != AE_OK) ||
545 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
546 status = wmi_status;
547 }
548 }
549
550 return status;
551}
552EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
553
554/**
555 * wmi_uninstall_notify_handler - Unregister handler for WMI events
556 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
557 *
558 * Unregister handler for events sent to the ACPI-WMI mapper device.
559 */
560acpi_status wmi_remove_notify_handler(const char *guid)
561{
562 struct wmi_block *block;
563 acpi_status status = AE_NOT_EXIST;
564 guid_t guid_input;
565
566 if (!guid)
567 return AE_BAD_PARAMETER;
568
569 if (guid_parse(guid, &guid_input))
570 return AE_BAD_PARAMETER;
571
572 list_for_each_entry(block, &wmi_block_list, list) {
573 acpi_status wmi_status;
574
575 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
576 if (!block->handler ||
577 block->handler == wmi_notify_debug)
578 return AE_NULL_ENTRY;
579
580 if (debug_event) {
581 block->handler = wmi_notify_debug;
582 status = AE_OK;
583 } else {
584 wmi_status = wmi_method_enable(block, 0);
585 block->handler = NULL;
586 block->handler_data = NULL;
587 if ((wmi_status != AE_OK) ||
588 ((wmi_status == AE_OK) &&
589 (status == AE_NOT_EXIST)))
590 status = wmi_status;
591 }
592 }
593 }
594
595 return status;
596}
597EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
598
599/**
600 * wmi_get_event_data - Get WMI data associated with an event
601 *
602 * @event: Event to find
603 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
604 *
605 * Returns extra data associated with an event in WMI.
606 */
607acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
608{
609 struct acpi_object_list input;
610 union acpi_object params[1];
611 struct guid_block *gblock;
612 struct wmi_block *wblock;
613
614 input.count = 1;
615 input.pointer = params;
616 params[0].type = ACPI_TYPE_INTEGER;
617 params[0].integer.value = event;
618
619 list_for_each_entry(wblock, &wmi_block_list, list) {
620 gblock = &wblock->gblock;
621
622 if ((gblock->flags & ACPI_WMI_EVENT) &&
623 (gblock->notify_id == event))
624 return acpi_evaluate_object(wblock->acpi_device->handle,
625 "_WED", &input, out);
626 }
627
628 return AE_NOT_FOUND;
629}
630EXPORT_SYMBOL_GPL(wmi_get_event_data);
631
632/**
633 * wmi_has_guid - Check if a GUID is available
634 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
635 *
636 * Check if a given GUID is defined by _WDG
637 */
638bool wmi_has_guid(const char *guid_string)
639{
640 return find_guid(guid_string, NULL);
641}
642EXPORT_SYMBOL_GPL(wmi_has_guid);
643
644/**
645 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
646 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
647 *
648 * Find the _UID of ACPI device associated with this WMI GUID.
649 *
650 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
651 */
652char *wmi_get_acpi_device_uid(const char *guid_string)
653{
654 struct wmi_block *wblock = NULL;
655
656 if (!find_guid(guid_string, &wblock))
657 return NULL;
658
659 return acpi_device_uid(wblock->acpi_device);
660}
661EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
662
663static struct wmi_block *dev_to_wblock(struct device *dev)
664{
665 return container_of(dev, struct wmi_block, dev.dev);
666}
667
668static struct wmi_device *dev_to_wdev(struct device *dev)
669{
670 return container_of(dev, struct wmi_device, dev);
671}
672
673/*
674 * sysfs interface
675 */
676static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
677 char *buf)
678{
679 struct wmi_block *wblock = dev_to_wblock(dev);
680
681 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
682}
683static DEVICE_ATTR_RO(modalias);
684
685static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
686 char *buf)
687{
688 struct wmi_block *wblock = dev_to_wblock(dev);
689
690 return sprintf(buf, "%pUL\n", wblock->gblock.guid);
691}
692static DEVICE_ATTR_RO(guid);
693
694static ssize_t instance_count_show(struct device *dev,
695 struct device_attribute *attr, char *buf)
696{
697 struct wmi_block *wblock = dev_to_wblock(dev);
698
699 return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
700}
701static DEVICE_ATTR_RO(instance_count);
702
703static ssize_t expensive_show(struct device *dev,
704 struct device_attribute *attr, char *buf)
705{
706 struct wmi_block *wblock = dev_to_wblock(dev);
707
708 return sprintf(buf, "%d\n",
709 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
710}
711static DEVICE_ATTR_RO(expensive);
712
713static struct attribute *wmi_attrs[] = {
714 &dev_attr_modalias.attr,
715 &dev_attr_guid.attr,
716 &dev_attr_instance_count.attr,
717 &dev_attr_expensive.attr,
718 NULL,
719};
720ATTRIBUTE_GROUPS(wmi);
721
722static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
723 char *buf)
724{
725 struct wmi_block *wblock = dev_to_wblock(dev);
726
727 return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
728}
729static DEVICE_ATTR_RO(notify_id);
730
731static struct attribute *wmi_event_attrs[] = {
732 &dev_attr_notify_id.attr,
733 NULL,
734};
735ATTRIBUTE_GROUPS(wmi_event);
736
737static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
738 char *buf)
739{
740 struct wmi_block *wblock = dev_to_wblock(dev);
741
742 return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
743 wblock->gblock.object_id[1]);
744}
745static DEVICE_ATTR_RO(object_id);
746
747static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
748 char *buf)
749{
750 struct wmi_device *wdev = dev_to_wdev(dev);
751
752 return sprintf(buf, "%d\n", (int)wdev->setable);
753}
754static DEVICE_ATTR_RO(setable);
755
756static struct attribute *wmi_data_attrs[] = {
757 &dev_attr_object_id.attr,
758 &dev_attr_setable.attr,
759 NULL,
760};
761ATTRIBUTE_GROUPS(wmi_data);
762
763static struct attribute *wmi_method_attrs[] = {
764 &dev_attr_object_id.attr,
765 NULL,
766};
767ATTRIBUTE_GROUPS(wmi_method);
768
769static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
770{
771 struct wmi_block *wblock = dev_to_wblock(dev);
772
773 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
774 return -ENOMEM;
775
776 if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
777 return -ENOMEM;
778
779 return 0;
780}
781
782static void wmi_dev_release(struct device *dev)
783{
784 struct wmi_block *wblock = dev_to_wblock(dev);
785
786 kfree(wblock);
787}
788
789static int wmi_dev_match(struct device *dev, struct device_driver *driver)
790{
791 struct wmi_driver *wmi_driver =
792 container_of(driver, struct wmi_driver, driver);
793 struct wmi_block *wblock = dev_to_wblock(dev);
794 const struct wmi_device_id *id = wmi_driver->id_table;
795
796 if (id == NULL)
797 return 0;
798
799 while (*id->guid_string) {
800 guid_t driver_guid;
801
802 if (WARN_ON(guid_parse(id->guid_string, &driver_guid)))
803 continue;
804 if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
805 return 1;
806
807 id++;
808 }
809
810 return 0;
811}
812static int wmi_char_open(struct inode *inode, struct file *filp)
813{
814 const char *driver_name = filp->f_path.dentry->d_iname;
815 struct wmi_block *wblock = NULL;
816 struct wmi_block *next = NULL;
817
818 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
819 if (!wblock->dev.dev.driver)
820 continue;
821 if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
822 filp->private_data = wblock;
823 break;
824 }
825 }
826
827 if (!filp->private_data)
828 return -ENODEV;
829
830 return nonseekable_open(inode, filp);
831}
832
833static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
834 size_t length, loff_t *offset)
835{
836 struct wmi_block *wblock = filp->private_data;
837
838 return simple_read_from_buffer(buffer, length, offset,
839 &wblock->req_buf_size,
840 sizeof(wblock->req_buf_size));
841}
842
843static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
844{
845 struct wmi_ioctl_buffer __user *input =
846 (struct wmi_ioctl_buffer __user *) arg;
847 struct wmi_block *wblock = filp->private_data;
848 struct wmi_ioctl_buffer *buf = NULL;
849 struct wmi_driver *wdriver = NULL;
850 int ret;
851
852 if (_IOC_TYPE(cmd) != WMI_IOC)
853 return -ENOTTY;
854
855 /* make sure we're not calling a higher instance than exists*/
856 if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
857 return -EINVAL;
858
859 mutex_lock(&wblock->char_mutex);
860 buf = wblock->handler_data;
861 if (get_user(buf->length, &input->length)) {
862 dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
863 ret = -EFAULT;
864 goto out_ioctl;
865 }
866 /* if it's too small, abort */
867 if (buf->length < wblock->req_buf_size) {
868 dev_err(&wblock->dev.dev,
869 "Buffer %lld too small, need at least %lld\n",
870 buf->length, wblock->req_buf_size);
871 ret = -EINVAL;
872 goto out_ioctl;
873 }
874 /* if it's too big, warn, driver will only use what is needed */
875 if (buf->length > wblock->req_buf_size)
876 dev_warn(&wblock->dev.dev,
877 "Buffer %lld is bigger than required %lld\n",
878 buf->length, wblock->req_buf_size);
879
880 /* copy the structure from userspace */
881 if (copy_from_user(buf, input, wblock->req_buf_size)) {
882 dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
883 wblock->req_buf_size);
884 ret = -EFAULT;
885 goto out_ioctl;
886 }
887
888 /* let the driver do any filtering and do the call */
889 wdriver = container_of(wblock->dev.dev.driver,
890 struct wmi_driver, driver);
891 if (!try_module_get(wdriver->driver.owner)) {
892 ret = -EBUSY;
893 goto out_ioctl;
894 }
895 ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
896 module_put(wdriver->driver.owner);
897 if (ret)
898 goto out_ioctl;
899
900 /* return the result (only up to our internal buffer size) */
901 if (copy_to_user(input, buf, wblock->req_buf_size)) {
902 dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
903 wblock->req_buf_size);
904 ret = -EFAULT;
905 }
906
907out_ioctl:
908 mutex_unlock(&wblock->char_mutex);
909 return ret;
910}
911
912static const struct file_operations wmi_fops = {
913 .owner = THIS_MODULE,
914 .read = wmi_char_read,
915 .open = wmi_char_open,
916 .unlocked_ioctl = wmi_ioctl,
917 .compat_ioctl = compat_ptr_ioctl,
918};
919
920static int wmi_dev_probe(struct device *dev)
921{
922 struct wmi_block *wblock = dev_to_wblock(dev);
923 struct wmi_driver *wdriver =
924 container_of(dev->driver, struct wmi_driver, driver);
925 int ret = 0;
926 char *buf;
927
928 if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
929 dev_warn(dev, "failed to enable device -- probing anyway\n");
930
931 if (wdriver->probe) {
932 ret = wdriver->probe(dev_to_wdev(dev),
933 find_guid_context(wblock, wdriver));
934 if (ret != 0)
935 goto probe_failure;
936 }
937
938 /* driver wants a character device made */
939 if (wdriver->filter_callback) {
940 /* check that required buffer size declared by driver or MOF */
941 if (!wblock->req_buf_size) {
942 dev_err(&wblock->dev.dev,
943 "Required buffer size not set\n");
944 ret = -EINVAL;
945 goto probe_failure;
946 }
947
948 wblock->handler_data = kmalloc(wblock->req_buf_size,
949 GFP_KERNEL);
950 if (!wblock->handler_data) {
951 ret = -ENOMEM;
952 goto probe_failure;
953 }
954
955 buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
956 if (!buf) {
957 ret = -ENOMEM;
958 goto probe_string_failure;
959 }
960 wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
961 wblock->char_dev.name = buf;
962 wblock->char_dev.fops = &wmi_fops;
963 wblock->char_dev.mode = 0444;
964 ret = misc_register(&wblock->char_dev);
965 if (ret) {
966 dev_warn(dev, "failed to register char dev: %d\n", ret);
967 ret = -ENOMEM;
968 goto probe_misc_failure;
969 }
970 }
971
972 return 0;
973
974probe_misc_failure:
975 kfree(buf);
976probe_string_failure:
977 kfree(wblock->handler_data);
978probe_failure:
979 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
980 dev_warn(dev, "failed to disable device\n");
981 return ret;
982}
983
984static int wmi_dev_remove(struct device *dev)
985{
986 struct wmi_block *wblock = dev_to_wblock(dev);
987 struct wmi_driver *wdriver =
988 container_of(dev->driver, struct wmi_driver, driver);
989 int ret = 0;
990
991 if (wdriver->filter_callback) {
992 misc_deregister(&wblock->char_dev);
993 kfree(wblock->char_dev.name);
994 kfree(wblock->handler_data);
995 }
996
997 if (wdriver->remove)
998 ret = wdriver->remove(dev_to_wdev(dev));
999
1000 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
1001 dev_warn(dev, "failed to disable device\n");
1002
1003 return ret;
1004}
1005
1006static struct class wmi_bus_class = {
1007 .name = "wmi_bus",
1008};
1009
1010static struct bus_type wmi_bus_type = {
1011 .name = "wmi",
1012 .dev_groups = wmi_groups,
1013 .match = wmi_dev_match,
1014 .uevent = wmi_dev_uevent,
1015 .probe = wmi_dev_probe,
1016 .remove = wmi_dev_remove,
1017};
1018
1019static const struct device_type wmi_type_event = {
1020 .name = "event",
1021 .groups = wmi_event_groups,
1022 .release = wmi_dev_release,
1023};
1024
1025static const struct device_type wmi_type_method = {
1026 .name = "method",
1027 .groups = wmi_method_groups,
1028 .release = wmi_dev_release,
1029};
1030
1031static const struct device_type wmi_type_data = {
1032 .name = "data",
1033 .groups = wmi_data_groups,
1034 .release = wmi_dev_release,
1035};
1036
1037static int wmi_create_device(struct device *wmi_bus_dev,
1038 const struct guid_block *gblock,
1039 struct wmi_block *wblock,
1040 struct acpi_device *device)
1041{
1042 struct acpi_device_info *info;
1043 char method[5];
1044 int result;
1045
1046 if (gblock->flags & ACPI_WMI_EVENT) {
1047 wblock->dev.dev.type = &wmi_type_event;
1048 goto out_init;
1049 }
1050
1051 if (gblock->flags & ACPI_WMI_METHOD) {
1052 wblock->dev.dev.type = &wmi_type_method;
1053 mutex_init(&wblock->char_mutex);
1054 goto out_init;
1055 }
1056
1057 /*
1058 * Data Block Query Control Method (WQxx by convention) is
1059 * required per the WMI documentation. If it is not present,
1060 * we ignore this data block.
1061 */
1062 strcpy(method, "WQ");
1063 strncat(method, wblock->gblock.object_id, 2);
1064 result = get_subobj_info(device->handle, method, &info);
1065
1066 if (result) {
1067 dev_warn(wmi_bus_dev,
1068 "%s data block query control method not found\n",
1069 method);
1070 return result;
1071 }
1072
1073 wblock->dev.dev.type = &wmi_type_data;
1074
1075 /*
1076 * The Microsoft documentation specifically states:
1077 *
1078 * Data blocks registered with only a single instance
1079 * can ignore the parameter.
1080 *
1081 * ACPICA will get mad at us if we call the method with the wrong number
1082 * of arguments, so check what our method expects. (On some Dell
1083 * laptops, WQxx may not be a method at all.)
1084 */
1085 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1086 wblock->read_takes_no_args = true;
1087
1088 kfree(info);
1089
1090 strcpy(method, "WS");
1091 strncat(method, wblock->gblock.object_id, 2);
1092 result = get_subobj_info(device->handle, method, NULL);
1093
1094 if (result == 0)
1095 wblock->dev.setable = true;
1096
1097 out_init:
1098 wblock->dev.dev.bus = &wmi_bus_type;
1099 wblock->dev.dev.parent = wmi_bus_dev;
1100
1101 dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1102
1103 device_initialize(&wblock->dev.dev);
1104
1105 return 0;
1106}
1107
1108static void wmi_free_devices(struct acpi_device *device)
1109{
1110 struct wmi_block *wblock, *next;
1111
1112 /* Delete devices for all the GUIDs */
1113 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1114 if (wblock->acpi_device == device) {
1115 list_del(&wblock->list);
1116 device_unregister(&wblock->dev.dev);
1117 }
1118 }
1119}
1120
1121static bool guid_already_parsed(struct acpi_device *device, const u8 *guid)
1122{
1123 struct wmi_block *wblock;
1124
1125 list_for_each_entry(wblock, &wmi_block_list, list) {
1126 if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1127 /*
1128 * Because we historically didn't track the relationship
1129 * between GUIDs and ACPI nodes, we don't know whether
1130 * we need to suppress GUIDs that are unique on a
1131 * given node but duplicated across nodes.
1132 */
1133 dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1134 guid, dev_name(&wblock->acpi_device->dev));
1135 return true;
1136 }
1137 }
1138
1139 return false;
1140}
1141
1142/*
1143 * Parse the _WDG method for the GUID data blocks
1144 */
1145static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1146{
1147 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
1148 const struct guid_block *gblock;
1149 struct wmi_block *wblock, *next;
1150 union acpi_object *obj;
1151 acpi_status status;
1152 int retval = 0;
1153 u32 i, total;
1154
1155 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1156 if (ACPI_FAILURE(status))
1157 return -ENXIO;
1158
1159 obj = (union acpi_object *) out.pointer;
1160 if (!obj)
1161 return -ENXIO;
1162
1163 if (obj->type != ACPI_TYPE_BUFFER) {
1164 retval = -ENXIO;
1165 goto out_free_pointer;
1166 }
1167
1168 gblock = (const struct guid_block *)obj->buffer.pointer;
1169 total = obj->buffer.length / sizeof(struct guid_block);
1170
1171 for (i = 0; i < total; i++) {
1172 if (debug_dump_wdg)
1173 wmi_dump_wdg(&gblock[i]);
1174
1175 /*
1176 * Some WMI devices, like those for nVidia hooks, have a
1177 * duplicate GUID. It's not clear what we should do in this
1178 * case yet, so for now, we'll just ignore the duplicate
1179 * for device creation.
1180 */
1181 if (guid_already_parsed(device, gblock[i].guid))
1182 continue;
1183
1184 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1185 if (!wblock) {
1186 retval = -ENOMEM;
1187 break;
1188 }
1189
1190 wblock->acpi_device = device;
1191 wblock->gblock = gblock[i];
1192
1193 retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1194 if (retval) {
1195 kfree(wblock);
1196 continue;
1197 }
1198
1199 list_add_tail(&wblock->list, &wmi_block_list);
1200
1201 if (debug_event) {
1202 wblock->handler = wmi_notify_debug;
1203 wmi_method_enable(wblock, 1);
1204 }
1205 }
1206
1207 /*
1208 * Now that all of the devices are created, add them to the
1209 * device tree and probe subdrivers.
1210 */
1211 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1212 if (wblock->acpi_device != device)
1213 continue;
1214
1215 retval = device_add(&wblock->dev.dev);
1216 if (retval) {
1217 dev_err(wmi_bus_dev, "failed to register %pUL\n",
1218 wblock->gblock.guid);
1219 if (debug_event)
1220 wmi_method_enable(wblock, 0);
1221 list_del(&wblock->list);
1222 put_device(&wblock->dev.dev);
1223 }
1224 }
1225
1226out_free_pointer:
1227 kfree(out.pointer);
1228 return retval;
1229}
1230
1231/*
1232 * WMI can have EmbeddedControl access regions. In which case, we just want to
1233 * hand these off to the EC driver.
1234 */
1235static acpi_status
1236acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1237 u32 bits, u64 *value,
1238 void *handler_context, void *region_context)
1239{
1240 int result = 0, i = 0;
1241 u8 temp = 0;
1242
1243 if ((address > 0xFF) || !value)
1244 return AE_BAD_PARAMETER;
1245
1246 if (function != ACPI_READ && function != ACPI_WRITE)
1247 return AE_BAD_PARAMETER;
1248
1249 if (bits != 8)
1250 return AE_BAD_PARAMETER;
1251
1252 if (function == ACPI_READ) {
1253 result = ec_read(address, &temp);
1254 (*value) |= ((u64)temp) << i;
1255 } else {
1256 temp = 0xff & ((*value) >> i);
1257 result = ec_write(address, temp);
1258 }
1259
1260 switch (result) {
1261 case -EINVAL:
1262 return AE_BAD_PARAMETER;
1263 break;
1264 case -ENODEV:
1265 return AE_NOT_FOUND;
1266 break;
1267 case -ETIME:
1268 return AE_TIME;
1269 break;
1270 default:
1271 return AE_OK;
1272 }
1273}
1274
1275static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1276 void *context)
1277{
1278 struct guid_block *block;
1279 struct wmi_block *wblock;
1280 bool found_it = false;
1281
1282 list_for_each_entry(wblock, &wmi_block_list, list) {
1283 block = &wblock->gblock;
1284
1285 if (wblock->acpi_device->handle == handle &&
1286 (block->flags & ACPI_WMI_EVENT) &&
1287 (block->notify_id == event))
1288 {
1289 found_it = true;
1290 break;
1291 }
1292 }
1293
1294 if (!found_it)
1295 return;
1296
1297 /* If a driver is bound, then notify the driver. */
1298 if (wblock->dev.dev.driver) {
1299 struct wmi_driver *driver;
1300 struct acpi_object_list input;
1301 union acpi_object params[1];
1302 struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1303 acpi_status status;
1304
1305 driver = container_of(wblock->dev.dev.driver,
1306 struct wmi_driver, driver);
1307
1308 input.count = 1;
1309 input.pointer = params;
1310 params[0].type = ACPI_TYPE_INTEGER;
1311 params[0].integer.value = event;
1312
1313 status = acpi_evaluate_object(wblock->acpi_device->handle,
1314 "_WED", &input, &evdata);
1315 if (ACPI_FAILURE(status)) {
1316 dev_warn(&wblock->dev.dev,
1317 "failed to get event data\n");
1318 return;
1319 }
1320
1321 if (driver->notify)
1322 driver->notify(&wblock->dev,
1323 (union acpi_object *)evdata.pointer);
1324
1325 kfree(evdata.pointer);
1326 } else if (wblock->handler) {
1327 /* Legacy handler */
1328 wblock->handler(event, wblock->handler_data);
1329 }
1330
1331 if (debug_event)
1332 pr_info("DEBUG Event GUID: %pUL\n", wblock->gblock.guid);
1333
1334 acpi_bus_generate_netlink_event(
1335 wblock->acpi_device->pnp.device_class,
1336 dev_name(&wblock->dev.dev),
1337 event, 0);
1338
1339}
1340
1341static int acpi_wmi_remove(struct platform_device *device)
1342{
1343 struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1344
1345 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1346 acpi_wmi_notify_handler);
1347 acpi_remove_address_space_handler(acpi_device->handle,
1348 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1349 wmi_free_devices(acpi_device);
1350 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1351
1352 return 0;
1353}
1354
1355static int acpi_wmi_probe(struct platform_device *device)
1356{
1357 struct acpi_device *acpi_device;
1358 struct device *wmi_bus_dev;
1359 acpi_status status;
1360 int error;
1361
1362 acpi_device = ACPI_COMPANION(&device->dev);
1363 if (!acpi_device) {
1364 dev_err(&device->dev, "ACPI companion is missing\n");
1365 return -ENODEV;
1366 }
1367
1368 status = acpi_install_address_space_handler(acpi_device->handle,
1369 ACPI_ADR_SPACE_EC,
1370 &acpi_wmi_ec_space_handler,
1371 NULL, NULL);
1372 if (ACPI_FAILURE(status)) {
1373 dev_err(&device->dev, "Error installing EC region handler\n");
1374 return -ENODEV;
1375 }
1376
1377 status = acpi_install_notify_handler(acpi_device->handle,
1378 ACPI_DEVICE_NOTIFY,
1379 acpi_wmi_notify_handler,
1380 NULL);
1381 if (ACPI_FAILURE(status)) {
1382 dev_err(&device->dev, "Error installing notify handler\n");
1383 error = -ENODEV;
1384 goto err_remove_ec_handler;
1385 }
1386
1387 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1388 NULL, "wmi_bus-%s", dev_name(&device->dev));
1389 if (IS_ERR(wmi_bus_dev)) {
1390 error = PTR_ERR(wmi_bus_dev);
1391 goto err_remove_notify_handler;
1392 }
1393 dev_set_drvdata(&device->dev, wmi_bus_dev);
1394
1395 error = parse_wdg(wmi_bus_dev, acpi_device);
1396 if (error) {
1397 pr_err("Failed to parse WDG method\n");
1398 goto err_remove_busdev;
1399 }
1400
1401 return 0;
1402
1403err_remove_busdev:
1404 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1405
1406err_remove_notify_handler:
1407 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1408 acpi_wmi_notify_handler);
1409
1410err_remove_ec_handler:
1411 acpi_remove_address_space_handler(acpi_device->handle,
1412 ACPI_ADR_SPACE_EC,
1413 &acpi_wmi_ec_space_handler);
1414
1415 return error;
1416}
1417
1418int __must_check __wmi_driver_register(struct wmi_driver *driver,
1419 struct module *owner)
1420{
1421 driver->driver.owner = owner;
1422 driver->driver.bus = &wmi_bus_type;
1423
1424 return driver_register(&driver->driver);
1425}
1426EXPORT_SYMBOL(__wmi_driver_register);
1427
1428void wmi_driver_unregister(struct wmi_driver *driver)
1429{
1430 driver_unregister(&driver->driver);
1431}
1432EXPORT_SYMBOL(wmi_driver_unregister);
1433
1434static int __init acpi_wmi_init(void)
1435{
1436 int error;
1437
1438 if (acpi_disabled)
1439 return -ENODEV;
1440
1441 error = class_register(&wmi_bus_class);
1442 if (error)
1443 return error;
1444
1445 error = bus_register(&wmi_bus_type);
1446 if (error)
1447 goto err_unreg_class;
1448
1449 error = platform_driver_register(&acpi_wmi_driver);
1450 if (error) {
1451 pr_err("Error loading mapper\n");
1452 goto err_unreg_bus;
1453 }
1454
1455 return 0;
1456
1457err_unreg_bus:
1458 bus_unregister(&wmi_bus_type);
1459
1460err_unreg_class:
1461 class_unregister(&wmi_bus_class);
1462
1463 return error;
1464}
1465
1466static void __exit acpi_wmi_exit(void)
1467{
1468 platform_driver_unregister(&acpi_wmi_driver);
1469 bus_unregister(&wmi_bus_type);
1470 class_unregister(&wmi_bus_class);
1471}
1472
1473subsys_initcall_sync(acpi_wmi_init);
1474module_exit(acpi_wmi_exit);