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