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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/*
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 * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
12 * Copyright (C) 2015 Andrew Lutomirski
13 * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
14 *
15 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or (at
20 * your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful, but
23 * WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25 * General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License along
28 * with this program; if not, write to the Free Software Foundation, Inc.,
29 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
30 *
31 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
32 */
33
34#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
35
36#include <linux/acpi.h>
37#include <linux/device.h>
38#include <linux/init.h>
39#include <linux/kernel.h>
40#include <linux/list.h>
41#include <linux/miscdevice.h>
42#include <linux/module.h>
43#include <linux/platform_device.h>
44#include <linux/slab.h>
45#include <linux/types.h>
46#include <linux/uaccess.h>
47#include <linux/uuid.h>
48#include <linux/wmi.h>
49#include <uapi/linux/wmi.h>
50
51ACPI_MODULE_NAME("wmi");
52MODULE_AUTHOR("Carlos Corbacho");
53MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
54MODULE_LICENSE("GPL");
55
56static LIST_HEAD(wmi_block_list);
57
58struct guid_block {
59 char guid[16];
60 union {
61 char object_id[2];
62 struct {
63 unsigned char notify_id;
64 unsigned char reserved;
65 };
66 };
67 u8 instance_count;
68 u8 flags;
69};
70
71struct wmi_block {
72 struct wmi_device dev;
73 struct list_head list;
74 struct guid_block gblock;
75 struct miscdevice char_dev;
76 struct mutex char_mutex;
77 struct acpi_device *acpi_device;
78 wmi_notify_handler handler;
79 void *handler_data;
80 u64 req_buf_size;
81
82 bool read_takes_no_args;
83};
84
85
86/*
87 * If the GUID data block is marked as expensive, we must enable and
88 * explicitily disable data collection.
89 */
90#define ACPI_WMI_EXPENSIVE 0x1
91#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
92#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
93#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
94
95static bool debug_event;
96module_param(debug_event, bool, 0444);
97MODULE_PARM_DESC(debug_event,
98 "Log WMI Events [0/1]");
99
100static bool debug_dump_wdg;
101module_param(debug_dump_wdg, bool, 0444);
102MODULE_PARM_DESC(debug_dump_wdg,
103 "Dump available WMI interfaces [0/1]");
104
105static int acpi_wmi_remove(struct platform_device *device);
106static int acpi_wmi_probe(struct platform_device *device);
107
108static const struct acpi_device_id wmi_device_ids[] = {
109 {"PNP0C14", 0},
110 {"pnp0c14", 0},
111 {"", 0},
112};
113MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
114
115static struct platform_driver acpi_wmi_driver = {
116 .driver = {
117 .name = "acpi-wmi",
118 .acpi_match_table = wmi_device_ids,
119 },
120 .probe = acpi_wmi_probe,
121 .remove = acpi_wmi_remove,
122};
123
124/*
125 * GUID parsing functions
126 */
127
128static bool find_guid(const char *guid_string, struct wmi_block **out)
129{
130 uuid_le guid_input;
131 struct wmi_block *wblock;
132 struct guid_block *block;
133
134 if (uuid_le_to_bin(guid_string, &guid_input))
135 return false;
136
137 list_for_each_entry(wblock, &wmi_block_list, list) {
138 block = &wblock->gblock;
139
140 if (memcmp(block->guid, &guid_input, 16) == 0) {
141 if (out)
142 *out = wblock;
143 return true;
144 }
145 }
146 return false;
147}
148
149static int get_subobj_info(acpi_handle handle, const char *pathname,
150 struct acpi_device_info **info)
151{
152 struct acpi_device_info *dummy_info, **info_ptr;
153 acpi_handle subobj_handle;
154 acpi_status status;
155
156 status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
157 if (status == AE_NOT_FOUND)
158 return -ENOENT;
159 else if (ACPI_FAILURE(status))
160 return -EIO;
161
162 info_ptr = info ? info : &dummy_info;
163 status = acpi_get_object_info(subobj_handle, info_ptr);
164 if (ACPI_FAILURE(status))
165 return -EIO;
166
167 if (!info)
168 kfree(dummy_info);
169
170 return 0;
171}
172
173static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
174{
175 struct guid_block *block = NULL;
176 char method[5];
177 acpi_status status;
178 acpi_handle handle;
179
180 block = &wblock->gblock;
181 handle = wblock->acpi_device->handle;
182
183 snprintf(method, 5, "WE%02X", block->notify_id);
184 status = acpi_execute_simple_method(handle, method, enable);
185
186 if (status != AE_OK && status != AE_NOT_FOUND)
187 return status;
188 else
189 return AE_OK;
190}
191
192/*
193 * Exported WMI functions
194 */
195
196/**
197 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
198 * @wdev: A wmi bus device from a driver
199 * @instance: Instance index
200 *
201 * Allocates memory needed for buffer, stores the buffer size in that memory
202 */
203int set_required_buffer_size(struct wmi_device *wdev, u64 length)
204{
205 struct wmi_block *wblock;
206
207 wblock = container_of(wdev, struct wmi_block, dev);
208 wblock->req_buf_size = length;
209
210 return 0;
211}
212EXPORT_SYMBOL_GPL(set_required_buffer_size);
213
214/**
215 * wmi_evaluate_method - Evaluate a WMI method
216 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
217 * @instance: Instance index
218 * @method_id: Method ID to call
219 * &in: Buffer containing input for the method call
220 * &out: Empty buffer to return the method results
221 *
222 * Call an ACPI-WMI method
223 */
224acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
225u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
226{
227 struct wmi_block *wblock = NULL;
228
229 if (!find_guid(guid_string, &wblock))
230 return AE_ERROR;
231 return wmidev_evaluate_method(&wblock->dev, instance, method_id,
232 in, out);
233}
234EXPORT_SYMBOL_GPL(wmi_evaluate_method);
235
236/**
237 * wmidev_evaluate_method - Evaluate a WMI method
238 * @wdev: A wmi bus device from a driver
239 * @instance: Instance index
240 * @method_id: Method ID to call
241 * &in: Buffer containing input for the method call
242 * &out: Empty buffer to return the method results
243 *
244 * Call an ACPI-WMI method
245 */
246acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
247 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
248{
249 struct guid_block *block = NULL;
250 struct wmi_block *wblock = NULL;
251 acpi_handle handle;
252 acpi_status status;
253 struct acpi_object_list input;
254 union acpi_object params[3];
255 char method[5] = "WM";
256
257 wblock = container_of(wdev, struct wmi_block, dev);
258 block = &wblock->gblock;
259 handle = wblock->acpi_device->handle;
260
261 if (!(block->flags & ACPI_WMI_METHOD))
262 return AE_BAD_DATA;
263
264 if (block->instance_count <= instance)
265 return AE_BAD_PARAMETER;
266
267 input.count = 2;
268 input.pointer = params;
269 params[0].type = ACPI_TYPE_INTEGER;
270 params[0].integer.value = instance;
271 params[1].type = ACPI_TYPE_INTEGER;
272 params[1].integer.value = method_id;
273
274 if (in) {
275 input.count = 3;
276
277 if (block->flags & ACPI_WMI_STRING) {
278 params[2].type = ACPI_TYPE_STRING;
279 } else {
280 params[2].type = ACPI_TYPE_BUFFER;
281 }
282 params[2].buffer.length = in->length;
283 params[2].buffer.pointer = in->pointer;
284 }
285
286 strncat(method, block->object_id, 2);
287
288 status = acpi_evaluate_object(handle, method, &input, out);
289
290 return status;
291}
292EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
293
294static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
295 struct acpi_buffer *out)
296{
297 struct guid_block *block = NULL;
298 acpi_handle handle;
299 acpi_status status, wc_status = AE_ERROR;
300 struct acpi_object_list input;
301 union acpi_object wq_params[1];
302 char method[5];
303 char wc_method[5] = "WC";
304
305 if (!out)
306 return AE_BAD_PARAMETER;
307
308 block = &wblock->gblock;
309 handle = wblock->acpi_device->handle;
310
311 if (block->instance_count <= instance)
312 return AE_BAD_PARAMETER;
313
314 /* Check GUID is a data block */
315 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
316 return AE_ERROR;
317
318 input.count = 1;
319 input.pointer = wq_params;
320 wq_params[0].type = ACPI_TYPE_INTEGER;
321 wq_params[0].integer.value = instance;
322
323 if (instance == 0 && wblock->read_takes_no_args)
324 input.count = 0;
325
326 /*
327 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
328 * enable collection.
329 */
330 if (block->flags & ACPI_WMI_EXPENSIVE) {
331 strncat(wc_method, block->object_id, 2);
332
333 /*
334 * Some GUIDs break the specification by declaring themselves
335 * expensive, but have no corresponding WCxx method. So we
336 * should not fail if this happens.
337 */
338 if (acpi_has_method(handle, wc_method))
339 wc_status = acpi_execute_simple_method(handle,
340 wc_method, 1);
341 }
342
343 strcpy(method, "WQ");
344 strncat(method, block->object_id, 2);
345
346 status = acpi_evaluate_object(handle, method, &input, out);
347
348 /*
349 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
350 * the WQxx method failed - we should disable collection anyway.
351 */
352 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
353 status = acpi_execute_simple_method(handle, wc_method, 0);
354 }
355
356 return status;
357}
358
359/**
360 * wmi_query_block - Return contents of a WMI block (deprecated)
361 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
362 * @instance: Instance index
363 * &out: Empty buffer to return the contents of the data block to
364 *
365 * Return the contents of an ACPI-WMI data block to a buffer
366 */
367acpi_status wmi_query_block(const char *guid_string, u8 instance,
368 struct acpi_buffer *out)
369{
370 struct wmi_block *wblock;
371
372 if (!guid_string)
373 return AE_BAD_PARAMETER;
374
375 if (!find_guid(guid_string, &wblock))
376 return AE_ERROR;
377
378 return __query_block(wblock, instance, out);
379}
380EXPORT_SYMBOL_GPL(wmi_query_block);
381
382union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
383{
384 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
385 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
386
387 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
388 return NULL;
389
390 return (union acpi_object *)out.pointer;
391}
392EXPORT_SYMBOL_GPL(wmidev_block_query);
393
394/**
395 * wmi_set_block - Write to a WMI block
396 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
397 * @instance: Instance index
398 * &in: Buffer containing new values for the data block
399 *
400 * Write the contents of the input buffer to an ACPI-WMI data block
401 */
402acpi_status wmi_set_block(const char *guid_string, u8 instance,
403 const struct acpi_buffer *in)
404{
405 struct guid_block *block = NULL;
406 struct wmi_block *wblock = NULL;
407 acpi_handle handle;
408 struct acpi_object_list input;
409 union acpi_object params[2];
410 char method[5] = "WS";
411
412 if (!guid_string || !in)
413 return AE_BAD_DATA;
414
415 if (!find_guid(guid_string, &wblock))
416 return AE_ERROR;
417
418 block = &wblock->gblock;
419 handle = wblock->acpi_device->handle;
420
421 if (block->instance_count <= instance)
422 return AE_BAD_PARAMETER;
423
424 /* Check GUID is a data block */
425 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
426 return AE_ERROR;
427
428 input.count = 2;
429 input.pointer = params;
430 params[0].type = ACPI_TYPE_INTEGER;
431 params[0].integer.value = instance;
432
433 if (block->flags & ACPI_WMI_STRING) {
434 params[1].type = ACPI_TYPE_STRING;
435 } else {
436 params[1].type = ACPI_TYPE_BUFFER;
437 }
438 params[1].buffer.length = in->length;
439 params[1].buffer.pointer = in->pointer;
440
441 strncat(method, block->object_id, 2);
442
443 return acpi_evaluate_object(handle, method, &input, NULL);
444}
445EXPORT_SYMBOL_GPL(wmi_set_block);
446
447static void wmi_dump_wdg(const struct guid_block *g)
448{
449 pr_info("%pUL:\n", g->guid);
450 if (g->flags & ACPI_WMI_EVENT)
451 pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
452 else
453 pr_info("\tobject_id: %2pE\n", g->object_id);
454 pr_info("\tinstance_count: %d\n", g->instance_count);
455 pr_info("\tflags: %#x", g->flags);
456 if (g->flags) {
457 if (g->flags & ACPI_WMI_EXPENSIVE)
458 pr_cont(" ACPI_WMI_EXPENSIVE");
459 if (g->flags & ACPI_WMI_METHOD)
460 pr_cont(" ACPI_WMI_METHOD");
461 if (g->flags & ACPI_WMI_STRING)
462 pr_cont(" ACPI_WMI_STRING");
463 if (g->flags & ACPI_WMI_EVENT)
464 pr_cont(" ACPI_WMI_EVENT");
465 }
466 pr_cont("\n");
467
468}
469
470static void wmi_notify_debug(u32 value, void *context)
471{
472 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
473 union acpi_object *obj;
474 acpi_status status;
475
476 status = wmi_get_event_data(value, &response);
477 if (status != AE_OK) {
478 pr_info("bad event status 0x%x\n", status);
479 return;
480 }
481
482 obj = (union acpi_object *)response.pointer;
483
484 if (!obj)
485 return;
486
487 pr_info("DEBUG Event ");
488 switch(obj->type) {
489 case ACPI_TYPE_BUFFER:
490 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
491 break;
492 case ACPI_TYPE_STRING:
493 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
494 break;
495 case ACPI_TYPE_INTEGER:
496 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
497 break;
498 case ACPI_TYPE_PACKAGE:
499 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
500 break;
501 default:
502 pr_cont("object type 0x%X\n", obj->type);
503 }
504 kfree(obj);
505}
506
507/**
508 * wmi_install_notify_handler - Register handler for WMI events
509 * @handler: Function to handle notifications
510 * @data: Data to be returned to handler when event is fired
511 *
512 * Register a handler for events sent to the ACPI-WMI mapper device.
513 */
514acpi_status wmi_install_notify_handler(const char *guid,
515wmi_notify_handler handler, void *data)
516{
517 struct wmi_block *block;
518 acpi_status status = AE_NOT_EXIST;
519 uuid_le guid_input;
520
521 if (!guid || !handler)
522 return AE_BAD_PARAMETER;
523
524 if (uuid_le_to_bin(guid, &guid_input))
525 return AE_BAD_PARAMETER;
526
527 list_for_each_entry(block, &wmi_block_list, list) {
528 acpi_status wmi_status;
529
530 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
531 if (block->handler &&
532 block->handler != wmi_notify_debug)
533 return AE_ALREADY_ACQUIRED;
534
535 block->handler = handler;
536 block->handler_data = data;
537
538 wmi_status = wmi_method_enable(block, 1);
539 if ((wmi_status != AE_OK) ||
540 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
541 status = wmi_status;
542 }
543 }
544
545 return status;
546}
547EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
548
549/**
550 * wmi_uninstall_notify_handler - Unregister handler for WMI events
551 *
552 * Unregister handler for events sent to the ACPI-WMI mapper device.
553 */
554acpi_status wmi_remove_notify_handler(const char *guid)
555{
556 struct wmi_block *block;
557 acpi_status status = AE_NOT_EXIST;
558 uuid_le guid_input;
559
560 if (!guid)
561 return AE_BAD_PARAMETER;
562
563 if (uuid_le_to_bin(guid, &guid_input))
564 return AE_BAD_PARAMETER;
565
566 list_for_each_entry(block, &wmi_block_list, list) {
567 acpi_status wmi_status;
568
569 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
570 if (!block->handler ||
571 block->handler == wmi_notify_debug)
572 return AE_NULL_ENTRY;
573
574 if (debug_event) {
575 block->handler = wmi_notify_debug;
576 status = AE_OK;
577 } else {
578 wmi_status = wmi_method_enable(block, 0);
579 block->handler = NULL;
580 block->handler_data = NULL;
581 if ((wmi_status != AE_OK) ||
582 ((wmi_status == AE_OK) &&
583 (status == AE_NOT_EXIST)))
584 status = wmi_status;
585 }
586 }
587 }
588
589 return status;
590}
591EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
592
593/**
594 * wmi_get_event_data - Get WMI data associated with an event
595 *
596 * @event: Event to find
597 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
598 *
599 * Returns extra data associated with an event in WMI.
600 */
601acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
602{
603 struct acpi_object_list input;
604 union acpi_object params[1];
605 struct guid_block *gblock;
606 struct wmi_block *wblock;
607
608 input.count = 1;
609 input.pointer = params;
610 params[0].type = ACPI_TYPE_INTEGER;
611 params[0].integer.value = event;
612
613 list_for_each_entry(wblock, &wmi_block_list, list) {
614 gblock = &wblock->gblock;
615
616 if ((gblock->flags & ACPI_WMI_EVENT) &&
617 (gblock->notify_id == event))
618 return acpi_evaluate_object(wblock->acpi_device->handle,
619 "_WED", &input, out);
620 }
621
622 return AE_NOT_FOUND;
623}
624EXPORT_SYMBOL_GPL(wmi_get_event_data);
625
626/**
627 * wmi_has_guid - Check if a GUID is available
628 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
629 *
630 * Check if a given GUID is defined by _WDG
631 */
632bool wmi_has_guid(const char *guid_string)
633{
634 return find_guid(guid_string, NULL);
635}
636EXPORT_SYMBOL_GPL(wmi_has_guid);
637
638static struct wmi_block *dev_to_wblock(struct device *dev)
639{
640 return container_of(dev, struct wmi_block, dev.dev);
641}
642
643static struct wmi_device *dev_to_wdev(struct device *dev)
644{
645 return container_of(dev, struct wmi_device, dev);
646}
647
648/*
649 * sysfs interface
650 */
651static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
652 char *buf)
653{
654 struct wmi_block *wblock = dev_to_wblock(dev);
655
656 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
657}
658static DEVICE_ATTR_RO(modalias);
659
660static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
661 char *buf)
662{
663 struct wmi_block *wblock = dev_to_wblock(dev);
664
665 return sprintf(buf, "%pUL\n", wblock->gblock.guid);
666}
667static DEVICE_ATTR_RO(guid);
668
669static ssize_t instance_count_show(struct device *dev,
670 struct device_attribute *attr, char *buf)
671{
672 struct wmi_block *wblock = dev_to_wblock(dev);
673
674 return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
675}
676static DEVICE_ATTR_RO(instance_count);
677
678static ssize_t expensive_show(struct device *dev,
679 struct device_attribute *attr, char *buf)
680{
681 struct wmi_block *wblock = dev_to_wblock(dev);
682
683 return sprintf(buf, "%d\n",
684 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
685}
686static DEVICE_ATTR_RO(expensive);
687
688static struct attribute *wmi_attrs[] = {
689 &dev_attr_modalias.attr,
690 &dev_attr_guid.attr,
691 &dev_attr_instance_count.attr,
692 &dev_attr_expensive.attr,
693 NULL,
694};
695ATTRIBUTE_GROUPS(wmi);
696
697static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
698 char *buf)
699{
700 struct wmi_block *wblock = dev_to_wblock(dev);
701
702 return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
703}
704static DEVICE_ATTR_RO(notify_id);
705
706static struct attribute *wmi_event_attrs[] = {
707 &dev_attr_notify_id.attr,
708 NULL,
709};
710ATTRIBUTE_GROUPS(wmi_event);
711
712static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
713 char *buf)
714{
715 struct wmi_block *wblock = dev_to_wblock(dev);
716
717 return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
718 wblock->gblock.object_id[1]);
719}
720static DEVICE_ATTR_RO(object_id);
721
722static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
723 char *buf)
724{
725 struct wmi_device *wdev = dev_to_wdev(dev);
726
727 return sprintf(buf, "%d\n", (int)wdev->setable);
728}
729static DEVICE_ATTR_RO(setable);
730
731static struct attribute *wmi_data_attrs[] = {
732 &dev_attr_object_id.attr,
733 &dev_attr_setable.attr,
734 NULL,
735};
736ATTRIBUTE_GROUPS(wmi_data);
737
738static struct attribute *wmi_method_attrs[] = {
739 &dev_attr_object_id.attr,
740 NULL,
741};
742ATTRIBUTE_GROUPS(wmi_method);
743
744static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
745{
746 struct wmi_block *wblock = dev_to_wblock(dev);
747
748 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
749 return -ENOMEM;
750
751 if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
752 return -ENOMEM;
753
754 return 0;
755}
756
757static void wmi_dev_release(struct device *dev)
758{
759 struct wmi_block *wblock = dev_to_wblock(dev);
760
761 kfree(wblock);
762}
763
764static int wmi_dev_match(struct device *dev, struct device_driver *driver)
765{
766 struct wmi_driver *wmi_driver =
767 container_of(driver, struct wmi_driver, driver);
768 struct wmi_block *wblock = dev_to_wblock(dev);
769 const struct wmi_device_id *id = wmi_driver->id_table;
770
771 while (id->guid_string) {
772 uuid_le driver_guid;
773
774 if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid)))
775 continue;
776 if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
777 return 1;
778
779 id++;
780 }
781
782 return 0;
783}
784static int wmi_char_open(struct inode *inode, struct file *filp)
785{
786 const char *driver_name = filp->f_path.dentry->d_iname;
787 struct wmi_block *wblock = NULL;
788 struct wmi_block *next = NULL;
789
790 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
791 if (!wblock->dev.dev.driver)
792 continue;
793 if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
794 filp->private_data = wblock;
795 break;
796 }
797 }
798
799 if (!filp->private_data)
800 return -ENODEV;
801
802 return nonseekable_open(inode, filp);
803}
804
805static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
806 size_t length, loff_t *offset)
807{
808 struct wmi_block *wblock = filp->private_data;
809
810 return simple_read_from_buffer(buffer, length, offset,
811 &wblock->req_buf_size,
812 sizeof(wblock->req_buf_size));
813}
814
815static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
816{
817 struct wmi_ioctl_buffer __user *input =
818 (struct wmi_ioctl_buffer __user *) arg;
819 struct wmi_block *wblock = filp->private_data;
820 struct wmi_ioctl_buffer *buf = NULL;
821 struct wmi_driver *wdriver = NULL;
822 int ret;
823
824 if (_IOC_TYPE(cmd) != WMI_IOC)
825 return -ENOTTY;
826
827 /* make sure we're not calling a higher instance than exists*/
828 if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
829 return -EINVAL;
830
831 mutex_lock(&wblock->char_mutex);
832 buf = wblock->handler_data;
833 if (get_user(buf->length, &input->length)) {
834 dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
835 ret = -EFAULT;
836 goto out_ioctl;
837 }
838 /* if it's too small, abort */
839 if (buf->length < wblock->req_buf_size) {
840 dev_err(&wblock->dev.dev,
841 "Buffer %lld too small, need at least %lld\n",
842 buf->length, wblock->req_buf_size);
843 ret = -EINVAL;
844 goto out_ioctl;
845 }
846 /* if it's too big, warn, driver will only use what is needed */
847 if (buf->length > wblock->req_buf_size)
848 dev_warn(&wblock->dev.dev,
849 "Buffer %lld is bigger than required %lld\n",
850 buf->length, wblock->req_buf_size);
851
852 /* copy the structure from userspace */
853 if (copy_from_user(buf, input, wblock->req_buf_size)) {
854 dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
855 wblock->req_buf_size);
856 ret = -EFAULT;
857 goto out_ioctl;
858 }
859
860 /* let the driver do any filtering and do the call */
861 wdriver = container_of(wblock->dev.dev.driver,
862 struct wmi_driver, driver);
863 if (!try_module_get(wdriver->driver.owner)) {
864 ret = -EBUSY;
865 goto out_ioctl;
866 }
867 ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
868 module_put(wdriver->driver.owner);
869 if (ret)
870 goto out_ioctl;
871
872 /* return the result (only up to our internal buffer size) */
873 if (copy_to_user(input, buf, wblock->req_buf_size)) {
874 dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
875 wblock->req_buf_size);
876 ret = -EFAULT;
877 }
878
879out_ioctl:
880 mutex_unlock(&wblock->char_mutex);
881 return ret;
882}
883
884static const struct file_operations wmi_fops = {
885 .owner = THIS_MODULE,
886 .read = wmi_char_read,
887 .open = wmi_char_open,
888 .unlocked_ioctl = wmi_ioctl,
889 .compat_ioctl = wmi_ioctl,
890};
891
892static int wmi_dev_probe(struct device *dev)
893{
894 struct wmi_block *wblock = dev_to_wblock(dev);
895 struct wmi_driver *wdriver =
896 container_of(dev->driver, struct wmi_driver, driver);
897 int ret = 0;
898 int count;
899 char *buf;
900
901 if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
902 dev_warn(dev, "failed to enable device -- probing anyway\n");
903
904 if (wdriver->probe) {
905 ret = wdriver->probe(dev_to_wdev(dev));
906 if (ret != 0)
907 goto probe_failure;
908 }
909
910 /* driver wants a character device made */
911 if (wdriver->filter_callback) {
912 /* check that required buffer size declared by driver or MOF */
913 if (!wblock->req_buf_size) {
914 dev_err(&wblock->dev.dev,
915 "Required buffer size not set\n");
916 ret = -EINVAL;
917 goto probe_failure;
918 }
919
920 count = get_order(wblock->req_buf_size);
921 wblock->handler_data = (void *)__get_free_pages(GFP_KERNEL,
922 count);
923 if (!wblock->handler_data) {
924 ret = -ENOMEM;
925 goto probe_failure;
926 }
927
928 buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
929 if (!buf) {
930 ret = -ENOMEM;
931 goto probe_string_failure;
932 }
933 wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
934 wblock->char_dev.name = buf;
935 wblock->char_dev.fops = &wmi_fops;
936 wblock->char_dev.mode = 0444;
937 ret = misc_register(&wblock->char_dev);
938 if (ret) {
939 dev_warn(dev, "failed to register char dev: %d\n", ret);
940 ret = -ENOMEM;
941 goto probe_misc_failure;
942 }
943 }
944
945 return 0;
946
947probe_misc_failure:
948 kfree(buf);
949probe_string_failure:
950 kfree(wblock->handler_data);
951probe_failure:
952 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
953 dev_warn(dev, "failed to disable device\n");
954 return ret;
955}
956
957static int wmi_dev_remove(struct device *dev)
958{
959 struct wmi_block *wblock = dev_to_wblock(dev);
960 struct wmi_driver *wdriver =
961 container_of(dev->driver, struct wmi_driver, driver);
962 int ret = 0;
963
964 if (wdriver->filter_callback) {
965 misc_deregister(&wblock->char_dev);
966 kfree(wblock->char_dev.name);
967 free_pages((unsigned long)wblock->handler_data,
968 get_order(wblock->req_buf_size));
969 }
970
971 if (wdriver->remove)
972 ret = wdriver->remove(dev_to_wdev(dev));
973
974 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
975 dev_warn(dev, "failed to disable device\n");
976
977 return ret;
978}
979
980static struct class wmi_bus_class = {
981 .name = "wmi_bus",
982};
983
984static struct bus_type wmi_bus_type = {
985 .name = "wmi",
986 .dev_groups = wmi_groups,
987 .match = wmi_dev_match,
988 .uevent = wmi_dev_uevent,
989 .probe = wmi_dev_probe,
990 .remove = wmi_dev_remove,
991};
992
993static struct device_type wmi_type_event = {
994 .name = "event",
995 .groups = wmi_event_groups,
996 .release = wmi_dev_release,
997};
998
999static struct device_type wmi_type_method = {
1000 .name = "method",
1001 .groups = wmi_method_groups,
1002 .release = wmi_dev_release,
1003};
1004
1005static struct device_type wmi_type_data = {
1006 .name = "data",
1007 .groups = wmi_data_groups,
1008 .release = wmi_dev_release,
1009};
1010
1011static int wmi_create_device(struct device *wmi_bus_dev,
1012 const struct guid_block *gblock,
1013 struct wmi_block *wblock,
1014 struct acpi_device *device)
1015{
1016 struct acpi_device_info *info;
1017 char method[5];
1018 int result;
1019
1020 if (gblock->flags & ACPI_WMI_EVENT) {
1021 wblock->dev.dev.type = &wmi_type_event;
1022 goto out_init;
1023 }
1024
1025 if (gblock->flags & ACPI_WMI_METHOD) {
1026 wblock->dev.dev.type = &wmi_type_method;
1027 mutex_init(&wblock->char_mutex);
1028 goto out_init;
1029 }
1030
1031 /*
1032 * Data Block Query Control Method (WQxx by convention) is
1033 * required per the WMI documentation. If it is not present,
1034 * we ignore this data block.
1035 */
1036 strcpy(method, "WQ");
1037 strncat(method, wblock->gblock.object_id, 2);
1038 result = get_subobj_info(device->handle, method, &info);
1039
1040 if (result) {
1041 dev_warn(wmi_bus_dev,
1042 "%s data block query control method not found\n",
1043 method);
1044 return result;
1045 }
1046
1047 wblock->dev.dev.type = &wmi_type_data;
1048
1049 /*
1050 * The Microsoft documentation specifically states:
1051 *
1052 * Data blocks registered with only a single instance
1053 * can ignore the parameter.
1054 *
1055 * ACPICA will get mad at us if we call the method with the wrong number
1056 * of arguments, so check what our method expects. (On some Dell
1057 * laptops, WQxx may not be a method at all.)
1058 */
1059 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1060 wblock->read_takes_no_args = true;
1061
1062 kfree(info);
1063
1064 strcpy(method, "WS");
1065 strncat(method, wblock->gblock.object_id, 2);
1066 result = get_subobj_info(device->handle, method, NULL);
1067
1068 if (result == 0)
1069 wblock->dev.setable = true;
1070
1071 out_init:
1072 wblock->dev.dev.bus = &wmi_bus_type;
1073 wblock->dev.dev.parent = wmi_bus_dev;
1074
1075 dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1076
1077 device_initialize(&wblock->dev.dev);
1078
1079 return 0;
1080}
1081
1082static void wmi_free_devices(struct acpi_device *device)
1083{
1084 struct wmi_block *wblock, *next;
1085
1086 /* Delete devices for all the GUIDs */
1087 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1088 if (wblock->acpi_device == device) {
1089 list_del(&wblock->list);
1090 device_unregister(&wblock->dev.dev);
1091 }
1092 }
1093}
1094
1095static bool guid_already_parsed(struct acpi_device *device,
1096 const u8 *guid)
1097{
1098 struct wmi_block *wblock;
1099
1100 list_for_each_entry(wblock, &wmi_block_list, list) {
1101 if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1102 /*
1103 * Because we historically didn't track the relationship
1104 * between GUIDs and ACPI nodes, we don't know whether
1105 * we need to suppress GUIDs that are unique on a
1106 * given node but duplicated across nodes.
1107 */
1108 dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1109 guid, dev_name(&wblock->acpi_device->dev));
1110 return true;
1111 }
1112 }
1113
1114 return false;
1115}
1116
1117/*
1118 * Parse the _WDG method for the GUID data blocks
1119 */
1120static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1121{
1122 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
1123 const struct guid_block *gblock;
1124 struct wmi_block *wblock, *next;
1125 union acpi_object *obj;
1126 acpi_status status;
1127 int retval = 0;
1128 u32 i, total;
1129
1130 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1131 if (ACPI_FAILURE(status))
1132 return -ENXIO;
1133
1134 obj = (union acpi_object *) out.pointer;
1135 if (!obj)
1136 return -ENXIO;
1137
1138 if (obj->type != ACPI_TYPE_BUFFER) {
1139 retval = -ENXIO;
1140 goto out_free_pointer;
1141 }
1142
1143 gblock = (const struct guid_block *)obj->buffer.pointer;
1144 total = obj->buffer.length / sizeof(struct guid_block);
1145
1146 for (i = 0; i < total; i++) {
1147 if (debug_dump_wdg)
1148 wmi_dump_wdg(&gblock[i]);
1149
1150 /*
1151 * Some WMI devices, like those for nVidia hooks, have a
1152 * duplicate GUID. It's not clear what we should do in this
1153 * case yet, so for now, we'll just ignore the duplicate
1154 * for device creation.
1155 */
1156 if (guid_already_parsed(device, gblock[i].guid))
1157 continue;
1158
1159 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1160 if (!wblock) {
1161 retval = -ENOMEM;
1162 break;
1163 }
1164
1165 wblock->acpi_device = device;
1166 wblock->gblock = gblock[i];
1167
1168 retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1169 if (retval) {
1170 kfree(wblock);
1171 continue;
1172 }
1173
1174 list_add_tail(&wblock->list, &wmi_block_list);
1175
1176 if (debug_event) {
1177 wblock->handler = wmi_notify_debug;
1178 wmi_method_enable(wblock, 1);
1179 }
1180 }
1181
1182 /*
1183 * Now that all of the devices are created, add them to the
1184 * device tree and probe subdrivers.
1185 */
1186 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1187 if (wblock->acpi_device != device)
1188 continue;
1189
1190 retval = device_add(&wblock->dev.dev);
1191 if (retval) {
1192 dev_err(wmi_bus_dev, "failed to register %pUL\n",
1193 wblock->gblock.guid);
1194 if (debug_event)
1195 wmi_method_enable(wblock, 0);
1196 list_del(&wblock->list);
1197 put_device(&wblock->dev.dev);
1198 }
1199 }
1200
1201out_free_pointer:
1202 kfree(out.pointer);
1203 return retval;
1204}
1205
1206/*
1207 * WMI can have EmbeddedControl access regions. In which case, we just want to
1208 * hand these off to the EC driver.
1209 */
1210static acpi_status
1211acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1212 u32 bits, u64 *value,
1213 void *handler_context, void *region_context)
1214{
1215 int result = 0, i = 0;
1216 u8 temp = 0;
1217
1218 if ((address > 0xFF) || !value)
1219 return AE_BAD_PARAMETER;
1220
1221 if (function != ACPI_READ && function != ACPI_WRITE)
1222 return AE_BAD_PARAMETER;
1223
1224 if (bits != 8)
1225 return AE_BAD_PARAMETER;
1226
1227 if (function == ACPI_READ) {
1228 result = ec_read(address, &temp);
1229 (*value) |= ((u64)temp) << i;
1230 } else {
1231 temp = 0xff & ((*value) >> i);
1232 result = ec_write(address, temp);
1233 }
1234
1235 switch (result) {
1236 case -EINVAL:
1237 return AE_BAD_PARAMETER;
1238 break;
1239 case -ENODEV:
1240 return AE_NOT_FOUND;
1241 break;
1242 case -ETIME:
1243 return AE_TIME;
1244 break;
1245 default:
1246 return AE_OK;
1247 }
1248}
1249
1250static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1251 void *context)
1252{
1253 struct guid_block *block;
1254 struct wmi_block *wblock;
1255 bool found_it = false;
1256
1257 list_for_each_entry(wblock, &wmi_block_list, list) {
1258 block = &wblock->gblock;
1259
1260 if (wblock->acpi_device->handle == handle &&
1261 (block->flags & ACPI_WMI_EVENT) &&
1262 (block->notify_id == event))
1263 {
1264 found_it = true;
1265 break;
1266 }
1267 }
1268
1269 if (!found_it)
1270 return;
1271
1272 /* If a driver is bound, then notify the driver. */
1273 if (wblock->dev.dev.driver) {
1274 struct wmi_driver *driver;
1275 struct acpi_object_list input;
1276 union acpi_object params[1];
1277 struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1278 acpi_status status;
1279
1280 driver = container_of(wblock->dev.dev.driver,
1281 struct wmi_driver, driver);
1282
1283 input.count = 1;
1284 input.pointer = params;
1285 params[0].type = ACPI_TYPE_INTEGER;
1286 params[0].integer.value = event;
1287
1288 status = acpi_evaluate_object(wblock->acpi_device->handle,
1289 "_WED", &input, &evdata);
1290 if (ACPI_FAILURE(status)) {
1291 dev_warn(&wblock->dev.dev,
1292 "failed to get event data\n");
1293 return;
1294 }
1295
1296 if (driver->notify)
1297 driver->notify(&wblock->dev,
1298 (union acpi_object *)evdata.pointer);
1299
1300 kfree(evdata.pointer);
1301 } else if (wblock->handler) {
1302 /* Legacy handler */
1303 wblock->handler(event, wblock->handler_data);
1304 }
1305
1306 if (debug_event) {
1307 pr_info("DEBUG Event GUID: %pUL\n",
1308 wblock->gblock.guid);
1309 }
1310
1311 acpi_bus_generate_netlink_event(
1312 wblock->acpi_device->pnp.device_class,
1313 dev_name(&wblock->dev.dev),
1314 event, 0);
1315
1316}
1317
1318static int acpi_wmi_remove(struct platform_device *device)
1319{
1320 struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1321
1322 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1323 acpi_wmi_notify_handler);
1324 acpi_remove_address_space_handler(acpi_device->handle,
1325 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1326 wmi_free_devices(acpi_device);
1327 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1328
1329 return 0;
1330}
1331
1332static int acpi_wmi_probe(struct platform_device *device)
1333{
1334 struct acpi_device *acpi_device;
1335 struct device *wmi_bus_dev;
1336 acpi_status status;
1337 int error;
1338
1339 acpi_device = ACPI_COMPANION(&device->dev);
1340 if (!acpi_device) {
1341 dev_err(&device->dev, "ACPI companion is missing\n");
1342 return -ENODEV;
1343 }
1344
1345 status = acpi_install_address_space_handler(acpi_device->handle,
1346 ACPI_ADR_SPACE_EC,
1347 &acpi_wmi_ec_space_handler,
1348 NULL, NULL);
1349 if (ACPI_FAILURE(status)) {
1350 dev_err(&device->dev, "Error installing EC region handler\n");
1351 return -ENODEV;
1352 }
1353
1354 status = acpi_install_notify_handler(acpi_device->handle,
1355 ACPI_DEVICE_NOTIFY,
1356 acpi_wmi_notify_handler,
1357 NULL);
1358 if (ACPI_FAILURE(status)) {
1359 dev_err(&device->dev, "Error installing notify handler\n");
1360 error = -ENODEV;
1361 goto err_remove_ec_handler;
1362 }
1363
1364 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1365 NULL, "wmi_bus-%s", dev_name(&device->dev));
1366 if (IS_ERR(wmi_bus_dev)) {
1367 error = PTR_ERR(wmi_bus_dev);
1368 goto err_remove_notify_handler;
1369 }
1370 dev_set_drvdata(&device->dev, wmi_bus_dev);
1371
1372 error = parse_wdg(wmi_bus_dev, acpi_device);
1373 if (error) {
1374 pr_err("Failed to parse WDG method\n");
1375 goto err_remove_busdev;
1376 }
1377
1378 return 0;
1379
1380err_remove_busdev:
1381 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1382
1383err_remove_notify_handler:
1384 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1385 acpi_wmi_notify_handler);
1386
1387err_remove_ec_handler:
1388 acpi_remove_address_space_handler(acpi_device->handle,
1389 ACPI_ADR_SPACE_EC,
1390 &acpi_wmi_ec_space_handler);
1391
1392 return error;
1393}
1394
1395int __must_check __wmi_driver_register(struct wmi_driver *driver,
1396 struct module *owner)
1397{
1398 driver->driver.owner = owner;
1399 driver->driver.bus = &wmi_bus_type;
1400
1401 return driver_register(&driver->driver);
1402}
1403EXPORT_SYMBOL(__wmi_driver_register);
1404
1405void wmi_driver_unregister(struct wmi_driver *driver)
1406{
1407 driver_unregister(&driver->driver);
1408}
1409EXPORT_SYMBOL(wmi_driver_unregister);
1410
1411static int __init acpi_wmi_init(void)
1412{
1413 int error;
1414
1415 if (acpi_disabled)
1416 return -ENODEV;
1417
1418 error = class_register(&wmi_bus_class);
1419 if (error)
1420 return error;
1421
1422 error = bus_register(&wmi_bus_type);
1423 if (error)
1424 goto err_unreg_class;
1425
1426 error = platform_driver_register(&acpi_wmi_driver);
1427 if (error) {
1428 pr_err("Error loading mapper\n");
1429 goto err_unreg_bus;
1430 }
1431
1432 return 0;
1433
1434err_unreg_bus:
1435 bus_unregister(&wmi_bus_type);
1436
1437err_unreg_class:
1438 class_unregister(&wmi_bus_class);
1439
1440 return error;
1441}
1442
1443static void __exit acpi_wmi_exit(void)
1444{
1445 platform_driver_unregister(&acpi_wmi_driver);
1446 bus_unregister(&wmi_bus_type);
1447 class_unregister(&wmi_bus_class);
1448}
1449
1450subsys_initcall_sync(acpi_wmi_init);
1451module_exit(acpi_wmi_exit);