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gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / platform / x86 / wmi.c
blob941739db7199f1ed975f8a9ff9be50db104a9a33
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * ACPI-WMI mapping driver
4 *
5 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
6 *
7 * GUID parsing code from ldm.c is:
8 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
9 * Copyright (c) 2001-2007 Anton Altaparmakov
10 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
11 *
12 * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
13 * Copyright (C) 2015 Andrew Lutomirski
14 * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
15 */
16
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19 #include <linux/acpi.h>
20 #include <linux/device.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/list.h>
24 #include <linux/miscdevice.h>
25 #include <linux/module.h>
26 #include <linux/platform_device.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29 #include <linux/uaccess.h>
30 #include <linux/uuid.h>
31 #include <linux/wmi.h>
32 #include <linux/fs.h>
33 #include <uapi/linux/wmi.h>
34
35 ACPI_MODULE_NAME("wmi");
36 MODULE_AUTHOR("Carlos Corbacho");
37 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
38 MODULE_LICENSE("GPL");
39
40 static LIST_HEAD(wmi_block_list);
41
42 struct guid_block {
43 char guid[16];
44 union {
45 char object_id[2];
46 struct {
47 unsigned char notify_id;
48 unsigned char reserved;
49 };
50 };
51 u8 instance_count;
52 u8 flags;
53 };
54
55 struct wmi_block {
56 struct wmi_device dev;
57 struct list_head list;
58 struct guid_block gblock;
59 struct miscdevice char_dev;
60 struct mutex char_mutex;
61 struct acpi_device *acpi_device;
62 wmi_notify_handler handler;
63 void *handler_data;
64 u64 req_buf_size;
65
66 bool read_takes_no_args;
67 };
68
69
70 /*
71 * If the GUID data block is marked as expensive, we must enable and
72 * explicitily disable data collection.
73 */
74 #define ACPI_WMI_EXPENSIVE 0x1
75 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
76 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
77 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
78
79 static bool debug_event;
80 module_param(debug_event, bool, 0444);
81 MODULE_PARM_DESC(debug_event,
82 "Log WMI Events [0/1]");
83
84 static bool debug_dump_wdg;
85 module_param(debug_dump_wdg, bool, 0444);
86 MODULE_PARM_DESC(debug_dump_wdg,
87 "Dump available WMI interfaces [0/1]");
88
89 static int acpi_wmi_remove(struct platform_device *device);
90 static int acpi_wmi_probe(struct platform_device *device);
91
92 static const struct acpi_device_id wmi_device_ids[] = {
93 {"PNP0C14", 0},
94 {"pnp0c14", 0},
95 {"", 0},
96 };
97 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
98
99 static struct platform_driver acpi_wmi_driver = {
100 .driver = {
101 .name = "acpi-wmi",
102 .acpi_match_table = wmi_device_ids,
103 },
104 .probe = acpi_wmi_probe,
105 .remove = acpi_wmi_remove,
106 };
107
108 /*
109 * GUID parsing functions
110 */
111
112 static bool find_guid(const char *guid_string, struct wmi_block **out)
113 {
114 uuid_le guid_input;
115 struct wmi_block *wblock;
116 struct guid_block *block;
117
118 if (uuid_le_to_bin(guid_string, &guid_input))
119 return false;
120
121 list_for_each_entry(wblock, &wmi_block_list, list) {
122 block = &wblock->gblock;
123
124 if (memcmp(block->guid, &guid_input, 16) == 0) {
125 if (out)
126 *out = wblock;
127 return true;
128 }
129 }
130 return false;
131 }
132
133 static const void *find_guid_context(struct wmi_block *wblock,
134 struct wmi_driver *wdriver)
135 {
136 const struct wmi_device_id *id;
137 uuid_le guid_input;
138
139 if (wblock == NULL || wdriver == NULL)
140 return NULL;
141 if (wdriver->id_table == NULL)
142 return NULL;
143
144 id = wdriver->id_table;
145 while (*id->guid_string) {
146 if (uuid_le_to_bin(id->guid_string, &guid_input))
147 continue;
148 if (!memcmp(wblock->gblock.guid, &guid_input, 16))
149 return id->context;
150 id++;
151 }
152 return NULL;
153 }
154
155 static int get_subobj_info(acpi_handle handle, const char *pathname,
156 struct acpi_device_info **info)
157 {
158 struct acpi_device_info *dummy_info, **info_ptr;
159 acpi_handle subobj_handle;
160 acpi_status status;
161
162 status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
163 if (status == AE_NOT_FOUND)
164 return -ENOENT;
165 else if (ACPI_FAILURE(status))
166 return -EIO;
167
168 info_ptr = info ? info : &dummy_info;
169 status = acpi_get_object_info(subobj_handle, info_ptr);
170 if (ACPI_FAILURE(status))
171 return -EIO;
172
173 if (!info)
174 kfree(dummy_info);
175
176 return 0;
177 }
178
179 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
180 {
181 struct guid_block *block = NULL;
182 char method[5];
183 acpi_status status;
184 acpi_handle handle;
185
186 block = &wblock->gblock;
187 handle = wblock->acpi_device->handle;
188
189 snprintf(method, 5, "WE%02X", block->notify_id);
190 status = acpi_execute_simple_method(handle, method, enable);
191
192 if (status != AE_OK && status != AE_NOT_FOUND)
193 return status;
194 else
195 return AE_OK;
196 }
197
198 /*
199 * Exported WMI functions
200 */
201
202 /**
203 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
204 * @wdev: A wmi bus device from a driver
205 * @instance: Instance index
206 *
207 * Allocates memory needed for buffer, stores the buffer size in that memory
208 */
209 int set_required_buffer_size(struct wmi_device *wdev, u64 length)
210 {
211 struct wmi_block *wblock;
212
213 wblock = container_of(wdev, struct wmi_block, dev);
214 wblock->req_buf_size = length;
215
216 return 0;
217 }
218 EXPORT_SYMBOL_GPL(set_required_buffer_size);
219
220 /**
221 * wmi_evaluate_method - Evaluate a WMI method
222 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
223 * @instance: Instance index
224 * @method_id: Method ID to call
225 * &in: Buffer containing input for the method call
226 * &out: Empty buffer to return the method results
227 *
228 * Call an ACPI-WMI method
229 */
230 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
231 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
232 {
233 struct wmi_block *wblock = NULL;
234
235 if (!find_guid(guid_string, &wblock))
236 return AE_ERROR;
237 return wmidev_evaluate_method(&wblock->dev, instance, method_id,
238 in, out);
239 }
240 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
241
242 /**
243 * wmidev_evaluate_method - Evaluate a WMI method
244 * @wdev: A wmi bus device from a driver
245 * @instance: Instance index
246 * @method_id: Method ID to call
247 * &in: Buffer containing input for the method call
248 * &out: Empty buffer to return the method results
249 *
250 * Call an ACPI-WMI method
251 */
252 acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
253 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
254 {
255 struct guid_block *block = NULL;
256 struct wmi_block *wblock = NULL;
257 acpi_handle handle;
258 acpi_status status;
259 struct acpi_object_list input;
260 union acpi_object params[3];
261 char method[5] = "WM";
262
263 wblock = container_of(wdev, struct wmi_block, dev);
264 block = &wblock->gblock;
265 handle = wblock->acpi_device->handle;
266
267 if (!(block->flags & ACPI_WMI_METHOD))
268 return AE_BAD_DATA;
269
270 if (block->instance_count <= instance)
271 return AE_BAD_PARAMETER;
272
273 input.count = 2;
274 input.pointer = params;
275 params[0].type = ACPI_TYPE_INTEGER;
276 params[0].integer.value = instance;
277 params[1].type = ACPI_TYPE_INTEGER;
278 params[1].integer.value = method_id;
279
280 if (in) {
281 input.count = 3;
282
283 if (block->flags & ACPI_WMI_STRING) {
284 params[2].type = ACPI_TYPE_STRING;
285 } else {
286 params[2].type = ACPI_TYPE_BUFFER;
287 }
288 params[2].buffer.length = in->length;
289 params[2].buffer.pointer = in->pointer;
290 }
291
292 strncat(method, block->object_id, 2);
293
294 status = acpi_evaluate_object(handle, method, &input, out);
295
296 return status;
297 }
298 EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
299
300 static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
301 struct acpi_buffer *out)
302 {
303 struct guid_block *block = NULL;
304 acpi_handle handle;
305 acpi_status status, wc_status = AE_ERROR;
306 struct acpi_object_list input;
307 union acpi_object wq_params[1];
308 char method[5];
309 char wc_method[5] = "WC";
310
311 if (!out)
312 return AE_BAD_PARAMETER;
313
314 block = &wblock->gblock;
315 handle = wblock->acpi_device->handle;
316
317 if (block->instance_count <= instance)
318 return AE_BAD_PARAMETER;
319
320 /* Check GUID is a data block */
321 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
322 return AE_ERROR;
323
324 input.count = 1;
325 input.pointer = wq_params;
326 wq_params[0].type = ACPI_TYPE_INTEGER;
327 wq_params[0].integer.value = instance;
328
329 if (instance == 0 && wblock->read_takes_no_args)
330 input.count = 0;
331
332 /*
333 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
334 * enable collection.
335 */
336 if (block->flags & ACPI_WMI_EXPENSIVE) {
337 strncat(wc_method, block->object_id, 2);
338
339 /*
340 * Some GUIDs break the specification by declaring themselves
341 * expensive, but have no corresponding WCxx method. So we
342 * should not fail if this happens.
343 */
344 wc_status = acpi_execute_simple_method(handle, wc_method, 1);
345 }
346
347 strcpy(method, "WQ");
348 strncat(method, block->object_id, 2);
349
350 status = acpi_evaluate_object(handle, method, &input, out);
351
352 /*
353 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
354 * the WQxx method failed - we should disable collection anyway.
355 */
356 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
357 status = acpi_execute_simple_method(handle, wc_method, 0);
358 }
359
360 return status;
361 }
362
363 /**
364 * wmi_query_block - Return contents of a WMI block (deprecated)
365 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
366 * @instance: Instance index
367 * &out: Empty buffer to return the contents of the data block to
368 *
369 * Return the contents of an ACPI-WMI data block to a buffer
370 */
371 acpi_status wmi_query_block(const char *guid_string, u8 instance,
372 struct acpi_buffer *out)
373 {
374 struct wmi_block *wblock;
375
376 if (!guid_string)
377 return AE_BAD_PARAMETER;
378
379 if (!find_guid(guid_string, &wblock))
380 return AE_ERROR;
381
382 return __query_block(wblock, instance, out);
383 }
384 EXPORT_SYMBOL_GPL(wmi_query_block);
385
386 union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
387 {
388 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
389 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
390
391 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
392 return NULL;
393
394 return (union acpi_object *)out.pointer;
395 }
396 EXPORT_SYMBOL_GPL(wmidev_block_query);
397
398 /**
399 * wmi_set_block - Write to a WMI block
400 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
401 * @instance: Instance index
402 * &in: Buffer containing new values for the data block
403 *
404 * Write the contents of the input buffer to an ACPI-WMI data block
405 */
406 acpi_status wmi_set_block(const char *guid_string, u8 instance,
407 const struct acpi_buffer *in)
408 {
409 struct guid_block *block = NULL;
410 struct wmi_block *wblock = NULL;
411 acpi_handle handle;
412 struct acpi_object_list input;
413 union acpi_object params[2];
414 char method[5] = "WS";
415
416 if (!guid_string || !in)
417 return AE_BAD_DATA;
418
419 if (!find_guid(guid_string, &wblock))
420 return AE_ERROR;
421
422 block = &wblock->gblock;
423 handle = wblock->acpi_device->handle;
424
425 if (block->instance_count <= instance)
426 return AE_BAD_PARAMETER;
427
428 /* Check GUID is a data block */
429 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
430 return AE_ERROR;
431
432 input.count = 2;
433 input.pointer = params;
434 params[0].type = ACPI_TYPE_INTEGER;
435 params[0].integer.value = instance;
436
437 if (block->flags & ACPI_WMI_STRING) {
438 params[1].type = ACPI_TYPE_STRING;
439 } else {
440 params[1].type = ACPI_TYPE_BUFFER;
441 }
442 params[1].buffer.length = in->length;
443 params[1].buffer.pointer = in->pointer;
444
445 strncat(method, block->object_id, 2);
446
447 return acpi_evaluate_object(handle, method, &input, NULL);
448 }
449 EXPORT_SYMBOL_GPL(wmi_set_block);
450
451 static void wmi_dump_wdg(const struct guid_block *g)
452 {
453 pr_info("%pUL:\n", g->guid);
454 if (g->flags & ACPI_WMI_EVENT)
455 pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
456 else
457 pr_info("\tobject_id: %2pE\n", g->object_id);
458 pr_info("\tinstance_count: %d\n", g->instance_count);
459 pr_info("\tflags: %#x", g->flags);
460 if (g->flags) {
461 if (g->flags & ACPI_WMI_EXPENSIVE)
462 pr_cont(" ACPI_WMI_EXPENSIVE");
463 if (g->flags & ACPI_WMI_METHOD)
464 pr_cont(" ACPI_WMI_METHOD");
465 if (g->flags & ACPI_WMI_STRING)
466 pr_cont(" ACPI_WMI_STRING");
467 if (g->flags & ACPI_WMI_EVENT)
468 pr_cont(" ACPI_WMI_EVENT");
469 }
470 pr_cont("\n");
471
472 }
473
474 static void wmi_notify_debug(u32 value, void *context)
475 {
476 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
477 union acpi_object *obj;
478 acpi_status status;
479
480 status = wmi_get_event_data(value, &response);
481 if (status != AE_OK) {
482 pr_info("bad event status 0x%x\n", status);
483 return;
484 }
485
486 obj = (union acpi_object *)response.pointer;
487
488 if (!obj)
489 return;
490
491 pr_info("DEBUG Event ");
492 switch(obj->type) {
493 case ACPI_TYPE_BUFFER:
494 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
495 break;
496 case ACPI_TYPE_STRING:
497 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
498 break;
499 case ACPI_TYPE_INTEGER:
500 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
501 break;
502 case ACPI_TYPE_PACKAGE:
503 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
504 break;
505 default:
506 pr_cont("object type 0x%X\n", obj->type);
507 }
508 kfree(obj);
509 }
510
511 /**
512 * wmi_install_notify_handler - Register handler for WMI events
513 * @handler: Function to handle notifications
514 * @data: Data to be returned to handler when event is fired
515 *
516 * Register a handler for events sent to the ACPI-WMI mapper device.
517 */
518 acpi_status wmi_install_notify_handler(const char *guid,
519 wmi_notify_handler handler, void *data)
520 {
521 struct wmi_block *block;
522 acpi_status status = AE_NOT_EXIST;
523 uuid_le guid_input;
524
525 if (!guid || !handler)
526 return AE_BAD_PARAMETER;
527
528 if (uuid_le_to_bin(guid, &guid_input))
529 return AE_BAD_PARAMETER;
530
531 list_for_each_entry(block, &wmi_block_list, list) {
532 acpi_status wmi_status;
533
534 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
535 if (block->handler &&
536 block->handler != wmi_notify_debug)
537 return AE_ALREADY_ACQUIRED;
538
539 block->handler = handler;
540 block->handler_data = data;
541
542 wmi_status = wmi_method_enable(block, 1);
543 if ((wmi_status != AE_OK) ||
544 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
545 status = wmi_status;
546 }
547 }
548
549 return status;
550 }
551 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
552
553 /**
554 * wmi_uninstall_notify_handler - Unregister handler for WMI events
555 *
556 * Unregister handler for events sent to the ACPI-WMI mapper device.
557 */
558 acpi_status wmi_remove_notify_handler(const char *guid)
559 {
560 struct wmi_block *block;
561 acpi_status status = AE_NOT_EXIST;
562 uuid_le guid_input;
563
564 if (!guid)
565 return AE_BAD_PARAMETER;
566
567 if (uuid_le_to_bin(guid, &guid_input))
568 return AE_BAD_PARAMETER;
569
570 list_for_each_entry(block, &wmi_block_list, list) {
571 acpi_status wmi_status;
572
573 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
574 if (!block->handler ||
575 block->handler == wmi_notify_debug)
576 return AE_NULL_ENTRY;
577
578 if (debug_event) {
579 block->handler = wmi_notify_debug;
580 status = AE_OK;
581 } else {
582 wmi_status = wmi_method_enable(block, 0);
583 block->handler = NULL;
584 block->handler_data = NULL;
585 if ((wmi_status != AE_OK) ||
586 ((wmi_status == AE_OK) &&
587 (status == AE_NOT_EXIST)))
588 status = wmi_status;
589 }
590 }
591 }
592
593 return status;
594 }
595 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
596
597 /**
598 * wmi_get_event_data - Get WMI data associated with an event
599 *
600 * @event: Event to find
601 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
602 *
603 * Returns extra data associated with an event in WMI.
604 */
605 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
606 {
607 struct acpi_object_list input;
608 union acpi_object params[1];
609 struct guid_block *gblock;
610 struct wmi_block *wblock;
611
612 input.count = 1;
613 input.pointer = params;
614 params[0].type = ACPI_TYPE_INTEGER;
615 params[0].integer.value = event;
616
617 list_for_each_entry(wblock, &wmi_block_list, list) {
618 gblock = &wblock->gblock;
619
620 if ((gblock->flags & ACPI_WMI_EVENT) &&
621 (gblock->notify_id == event))
622 return acpi_evaluate_object(wblock->acpi_device->handle,
623 "_WED", &input, out);
624 }
625
626 return AE_NOT_FOUND;
627 }
628 EXPORT_SYMBOL_GPL(wmi_get_event_data);
629
630 /**
631 * wmi_has_guid - Check if a GUID is available
632 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
633 *
634 * Check if a given GUID is defined by _WDG
635 */
636 bool wmi_has_guid(const char *guid_string)
637 {
638 return find_guid(guid_string, NULL);
639 }
640 EXPORT_SYMBOL_GPL(wmi_has_guid);
641
642 /**
643 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
644 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
645 *
646 * Find the _UID of ACPI device associated with this WMI GUID.
647 *
648 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
649 */
650 char *wmi_get_acpi_device_uid(const char *guid_string)
651 {
652 struct wmi_block *wblock = NULL;
653
654 if (!find_guid(guid_string, &wblock))
655 return NULL;
656
657 return acpi_device_uid(wblock->acpi_device);
658 }
659 EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
660
661 static struct wmi_block *dev_to_wblock(struct device *dev)
662 {
663 return container_of(dev, struct wmi_block, dev.dev);
664 }
665
666 static struct wmi_device *dev_to_wdev(struct device *dev)
667 {
668 return container_of(dev, struct wmi_device, dev);
669 }
670
671 /*
672 * sysfs interface
673 */
674 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
675 char *buf)
676 {
677 struct wmi_block *wblock = dev_to_wblock(dev);
678
679 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
680 }
681 static DEVICE_ATTR_RO(modalias);
682
683 static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
684 char *buf)
685 {
686 struct wmi_block *wblock = dev_to_wblock(dev);
687
688 return sprintf(buf, "%pUL\n", wblock->gblock.guid);
689 }
690 static DEVICE_ATTR_RO(guid);
691
692 static ssize_t instance_count_show(struct device *dev,
693 struct device_attribute *attr, char *buf)
694 {
695 struct wmi_block *wblock = dev_to_wblock(dev);
696
697 return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
698 }
699 static DEVICE_ATTR_RO(instance_count);
700
701 static ssize_t expensive_show(struct device *dev,
702 struct device_attribute *attr, char *buf)
703 {
704 struct wmi_block *wblock = dev_to_wblock(dev);
705
706 return sprintf(buf, "%d\n",
707 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
708 }
709 static DEVICE_ATTR_RO(expensive);
710
711 static struct attribute *wmi_attrs[] = {
712 &dev_attr_modalias.attr,
713 &dev_attr_guid.attr,
714 &dev_attr_instance_count.attr,
715 &dev_attr_expensive.attr,
716 NULL,
717 };
718 ATTRIBUTE_GROUPS(wmi);
719
720 static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
721 char *buf)
722 {
723 struct wmi_block *wblock = dev_to_wblock(dev);
724
725 return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
726 }
727 static DEVICE_ATTR_RO(notify_id);
728
729 static struct attribute *wmi_event_attrs[] = {
730 &dev_attr_notify_id.attr,
731 NULL,
732 };
733 ATTRIBUTE_GROUPS(wmi_event);
734
735 static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
736 char *buf)
737 {
738 struct wmi_block *wblock = dev_to_wblock(dev);
739
740 return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
741 wblock->gblock.object_id[1]);
742 }
743 static DEVICE_ATTR_RO(object_id);
744
745 static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
746 char *buf)
747 {
748 struct wmi_device *wdev = dev_to_wdev(dev);
749
750 return sprintf(buf, "%d\n", (int)wdev->setable);
751 }
752 static DEVICE_ATTR_RO(setable);
753
754 static struct attribute *wmi_data_attrs[] = {
755 &dev_attr_object_id.attr,
756 &dev_attr_setable.attr,
757 NULL,
758 };
759 ATTRIBUTE_GROUPS(wmi_data);
760
761 static struct attribute *wmi_method_attrs[] = {
762 &dev_attr_object_id.attr,
763 NULL,
764 };
765 ATTRIBUTE_GROUPS(wmi_method);
766
767 static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
768 {
769 struct wmi_block *wblock = dev_to_wblock(dev);
770
771 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
772 return -ENOMEM;
773
774 if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
775 return -ENOMEM;
776
777 return 0;
778 }
779
780 static void wmi_dev_release(struct device *dev)
781 {
782 struct wmi_block *wblock = dev_to_wblock(dev);
783
784 kfree(wblock);
785 }
786
787 static int wmi_dev_match(struct device *dev, struct device_driver *driver)
788 {
789 struct wmi_driver *wmi_driver =
790 container_of(driver, struct wmi_driver, driver);
791 struct wmi_block *wblock = dev_to_wblock(dev);
792 const struct wmi_device_id *id = wmi_driver->id_table;
793
794 if (id == NULL)
795 return 0;
796
797 while (*id->guid_string) {
798 uuid_le driver_guid;
799
800 if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid)))
801 continue;
802 if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
803 return 1;
804
805 id++;
806 }
807
808 return 0;
809 }
810 static int wmi_char_open(struct inode *inode, struct file *filp)
811 {
812 const char *driver_name = filp->f_path.dentry->d_iname;
813 struct wmi_block *wblock = NULL;
814 struct wmi_block *next = NULL;
815
816 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
817 if (!wblock->dev.dev.driver)
818 continue;
819 if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
820 filp->private_data = wblock;
821 break;
822 }
823 }
824
825 if (!filp->private_data)
826 return -ENODEV;
827
828 return nonseekable_open(inode, filp);
829 }
830
831 static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
832 size_t length, loff_t *offset)
833 {
834 struct wmi_block *wblock = filp->private_data;
835
836 return simple_read_from_buffer(buffer, length, offset,
837 &wblock->req_buf_size,
838 sizeof(wblock->req_buf_size));
839 }
840
841 static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
842 {
843 struct wmi_ioctl_buffer __user *input =
844 (struct wmi_ioctl_buffer __user *) arg;
845 struct wmi_block *wblock = filp->private_data;
846 struct wmi_ioctl_buffer *buf = NULL;
847 struct wmi_driver *wdriver = NULL;
848 int ret;
849
850 if (_IOC_TYPE(cmd) != WMI_IOC)
851 return -ENOTTY;
852
853 /* make sure we're not calling a higher instance than exists*/
854 if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
855 return -EINVAL;
856
857 mutex_lock(&wblock->char_mutex);
858 buf = wblock->handler_data;
859 if (get_user(buf->length, &input->length)) {
860 dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
861 ret = -EFAULT;
862 goto out_ioctl;
863 }
864 /* if it's too small, abort */
865 if (buf->length < wblock->req_buf_size) {
866 dev_err(&wblock->dev.dev,
867 "Buffer %lld too small, need at least %lld\n",
868 buf->length, wblock->req_buf_size);
869 ret = -EINVAL;
870 goto out_ioctl;
871 }
872 /* if it's too big, warn, driver will only use what is needed */
873 if (buf->length > wblock->req_buf_size)
874 dev_warn(&wblock->dev.dev,
875 "Buffer %lld is bigger than required %lld\n",
876 buf->length, wblock->req_buf_size);
877
878 /* copy the structure from userspace */
879 if (copy_from_user(buf, input, wblock->req_buf_size)) {
880 dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
881 wblock->req_buf_size);
882 ret = -EFAULT;
883 goto out_ioctl;
884 }
885
886 /* let the driver do any filtering and do the call */
887 wdriver = container_of(wblock->dev.dev.driver,
888 struct wmi_driver, driver);
889 if (!try_module_get(wdriver->driver.owner)) {
890 ret = -EBUSY;
891 goto out_ioctl;
892 }
893 ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
894 module_put(wdriver->driver.owner);
895 if (ret)
896 goto out_ioctl;
897
898 /* return the result (only up to our internal buffer size) */
899 if (copy_to_user(input, buf, wblock->req_buf_size)) {
900 dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
901 wblock->req_buf_size);
902 ret = -EFAULT;
903 }
904
905 out_ioctl:
906 mutex_unlock(&wblock->char_mutex);
907 return ret;
908 }
909
910 static const struct file_operations wmi_fops = {
911 .owner = THIS_MODULE,
912 .read = wmi_char_read,
913 .open = wmi_char_open,
914 .unlocked_ioctl = wmi_ioctl,
915 .compat_ioctl = compat_ptr_ioctl,
916 };
917
918 static int wmi_dev_probe(struct device *dev)
919 {
920 struct wmi_block *wblock = dev_to_wblock(dev);
921 struct wmi_driver *wdriver =
922 container_of(dev->driver, struct wmi_driver, driver);
923 int ret = 0;
924 char *buf;
925
926 if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
927 dev_warn(dev, "failed to enable device -- probing anyway\n");
928
929 if (wdriver->probe) {
930 ret = wdriver->probe(dev_to_wdev(dev),
931 find_guid_context(wblock, wdriver));
932 if (ret != 0)
933 goto probe_failure;
934 }
935
936 /* driver wants a character device made */
937 if (wdriver->filter_callback) {
938 /* check that required buffer size declared by driver or MOF */
939 if (!wblock->req_buf_size) {
940 dev_err(&wblock->dev.dev,
941 "Required buffer size not set\n");
942 ret = -EINVAL;
943 goto probe_failure;
944 }
945
946 wblock->handler_data = kmalloc(wblock->req_buf_size,
947 GFP_KERNEL);
948 if (!wblock->handler_data) {
949 ret = -ENOMEM;
950 goto probe_failure;
951 }
952
953 buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
954 if (!buf) {
955 ret = -ENOMEM;
956 goto probe_string_failure;
957 }
958 wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
959 wblock->char_dev.name = buf;
960 wblock->char_dev.fops = &wmi_fops;
961 wblock->char_dev.mode = 0444;
962 ret = misc_register(&wblock->char_dev);
963 if (ret) {
964 dev_warn(dev, "failed to register char dev: %d\n", ret);
965 ret = -ENOMEM;
966 goto probe_misc_failure;
967 }
968 }
969
970 return 0;
971
972 probe_misc_failure:
973 kfree(buf);
974 probe_string_failure:
975 kfree(wblock->handler_data);
976 probe_failure:
977 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
978 dev_warn(dev, "failed to disable device\n");
979 return ret;
980 }
981
982 static int wmi_dev_remove(struct device *dev)
983 {
984 struct wmi_block *wblock = dev_to_wblock(dev);
985 struct wmi_driver *wdriver =
986 container_of(dev->driver, struct wmi_driver, driver);
987 int ret = 0;
988
989 if (wdriver->filter_callback) {
990 misc_deregister(&wblock->char_dev);
991 kfree(wblock->char_dev.name);
992 kfree(wblock->handler_data);
993 }
994
995 if (wdriver->remove)
996 ret = wdriver->remove(dev_to_wdev(dev));
997
998 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
999 dev_warn(dev, "failed to disable device\n");
1000
1001 return ret;
1002 }
1003
1004 static struct class wmi_bus_class = {
1005 .name = "wmi_bus",
1006 };
1007
1008 static struct bus_type wmi_bus_type = {
1009 .name = "wmi",
1010 .dev_groups = wmi_groups,
1011 .match = wmi_dev_match,
1012 .uevent = wmi_dev_uevent,
1013 .probe = wmi_dev_probe,
1014 .remove = wmi_dev_remove,
1015 };
1016
1017 static const struct device_type wmi_type_event = {
1018 .name = "event",
1019 .groups = wmi_event_groups,
1020 .release = wmi_dev_release,
1021 };
1022
1023 static const struct device_type wmi_type_method = {
1024 .name = "method",
1025 .groups = wmi_method_groups,
1026 .release = wmi_dev_release,
1027 };
1028
1029 static const struct device_type wmi_type_data = {
1030 .name = "data",
1031 .groups = wmi_data_groups,
1032 .release = wmi_dev_release,
1033 };
1034
1035 static int wmi_create_device(struct device *wmi_bus_dev,
1036 const struct guid_block *gblock,
1037 struct wmi_block *wblock,
1038 struct acpi_device *device)
1039 {
1040 struct acpi_device_info *info;
1041 char method[5];
1042 int result;
1043
1044 if (gblock->flags & ACPI_WMI_EVENT) {
1045 wblock->dev.dev.type = &wmi_type_event;
1046 goto out_init;
1047 }
1048
1049 if (gblock->flags & ACPI_WMI_METHOD) {
1050 wblock->dev.dev.type = &wmi_type_method;
1051 mutex_init(&wblock->char_mutex);
1052 goto out_init;
1053 }
1054
1055 /*
1056 * Data Block Query Control Method (WQxx by convention) is
1057 * required per the WMI documentation. If it is not present,
1058 * we ignore this data block.
1059 */
1060 strcpy(method, "WQ");
1061 strncat(method, wblock->gblock.object_id, 2);
1062 result = get_subobj_info(device->handle, method, &info);
1063
1064 if (result) {
1065 dev_warn(wmi_bus_dev,
1066 "%s data block query control method not found\n",
1067 method);
1068 return result;
1069 }
1070
1071 wblock->dev.dev.type = &wmi_type_data;
1072
1073 /*
1074 * The Microsoft documentation specifically states:
1075 *
1076 * Data blocks registered with only a single instance
1077 * can ignore the parameter.
1078 *
1079 * ACPICA will get mad at us if we call the method with the wrong number
1080 * of arguments, so check what our method expects. (On some Dell
1081 * laptops, WQxx may not be a method at all.)
1082 */
1083 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1084 wblock->read_takes_no_args = true;
1085
1086 kfree(info);
1087
1088 strcpy(method, "WS");
1089 strncat(method, wblock->gblock.object_id, 2);
1090 result = get_subobj_info(device->handle, method, NULL);
1091
1092 if (result == 0)
1093 wblock->dev.setable = true;
1094
1095 out_init:
1096 wblock->dev.dev.bus = &wmi_bus_type;
1097 wblock->dev.dev.parent = wmi_bus_dev;
1098
1099 dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1100
1101 device_initialize(&wblock->dev.dev);
1102
1103 return 0;
1104 }
1105
1106 static void wmi_free_devices(struct acpi_device *device)
1107 {
1108 struct wmi_block *wblock, *next;
1109
1110 /* Delete devices for all the GUIDs */
1111 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1112 if (wblock->acpi_device == device) {
1113 list_del(&wblock->list);
1114 device_unregister(&wblock->dev.dev);
1115 }
1116 }
1117 }
1118
1119 static bool guid_already_parsed(struct acpi_device *device,
1120 const u8 *guid)
1121 {
1122 struct wmi_block *wblock;
1123
1124 list_for_each_entry(wblock, &wmi_block_list, list) {
1125 if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1126 /*
1127 * Because we historically didn't track the relationship
1128 * between GUIDs and ACPI nodes, we don't know whether
1129 * we need to suppress GUIDs that are unique on a
1130 * given node but duplicated across nodes.
1131 */
1132 dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1133 guid, dev_name(&wblock->acpi_device->dev));
1134 return true;
1135 }
1136 }
1137
1138 return false;
1139 }
1140
1141 /*
1142 * Parse the _WDG method for the GUID data blocks
1143 */
1144 static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1145 {
1146 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
1147 const struct guid_block *gblock;
1148 struct wmi_block *wblock, *next;
1149 union acpi_object *obj;
1150 acpi_status status;
1151 int retval = 0;
1152 u32 i, total;
1153
1154 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1155 if (ACPI_FAILURE(status))
1156 return -ENXIO;
1157
1158 obj = (union acpi_object *) out.pointer;
1159 if (!obj)
1160 return -ENXIO;
1161
1162 if (obj->type != ACPI_TYPE_BUFFER) {
1163 retval = -ENXIO;
1164 goto out_free_pointer;
1165 }
1166
1167 gblock = (const struct guid_block *)obj->buffer.pointer;
1168 total = obj->buffer.length / sizeof(struct guid_block);
1169
1170 for (i = 0; i < total; i++) {
1171 if (debug_dump_wdg)
1172 wmi_dump_wdg(&gblock[i]);
1173
1174 /*
1175 * Some WMI devices, like those for nVidia hooks, have a
1176 * duplicate GUID. It's not clear what we should do in this
1177 * case yet, so for now, we'll just ignore the duplicate
1178 * for device creation.
1179 */
1180 if (guid_already_parsed(device, gblock[i].guid))
1181 continue;
1182
1183 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1184 if (!wblock) {
1185 retval = -ENOMEM;
1186 break;
1187 }
1188
1189 wblock->acpi_device = device;
1190 wblock->gblock = gblock[i];
1191
1192 retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1193 if (retval) {
1194 kfree(wblock);
1195 continue;
1196 }
1197
1198 list_add_tail(&wblock->list, &wmi_block_list);
1199
1200 if (debug_event) {
1201 wblock->handler = wmi_notify_debug;
1202 wmi_method_enable(wblock, 1);
1203 }
1204 }
1205
1206 /*
1207 * Now that all of the devices are created, add them to the
1208 * device tree and probe subdrivers.
1209 */
1210 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1211 if (wblock->acpi_device != device)
1212 continue;
1213
1214 retval = device_add(&wblock->dev.dev);
1215 if (retval) {
1216 dev_err(wmi_bus_dev, "failed to register %pUL\n",
1217 wblock->gblock.guid);
1218 if (debug_event)
1219 wmi_method_enable(wblock, 0);
1220 list_del(&wblock->list);
1221 put_device(&wblock->dev.dev);
1222 }
1223 }
1224
1225 out_free_pointer:
1226 kfree(out.pointer);
1227 return retval;
1228 }
1229
1230 /*
1231 * WMI can have EmbeddedControl access regions. In which case, we just want to
1232 * hand these off to the EC driver.
1233 */
1234 static acpi_status
1235 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1236 u32 bits, u64 *value,
1237 void *handler_context, void *region_context)
1238 {
1239 int result = 0, i = 0;
1240 u8 temp = 0;
1241
1242 if ((address > 0xFF) || !value)
1243 return AE_BAD_PARAMETER;
1244
1245 if (function != ACPI_READ && function != ACPI_WRITE)
1246 return AE_BAD_PARAMETER;
1247
1248 if (bits != 8)
1249 return AE_BAD_PARAMETER;
1250
1251 if (function == ACPI_READ) {
1252 result = ec_read(address, &temp);
1253 (*value) |= ((u64)temp) << i;
1254 } else {
1255 temp = 0xff & ((*value) >> i);
1256 result = ec_write(address, temp);
1257 }
1258
1259 switch (result) {
1260 case -EINVAL:
1261 return AE_BAD_PARAMETER;
1262 break;
1263 case -ENODEV:
1264 return AE_NOT_FOUND;
1265 break;
1266 case -ETIME:
1267 return AE_TIME;
1268 break;
1269 default:
1270 return AE_OK;
1271 }
1272 }
1273
1274 static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1275 void *context)
1276 {
1277 struct guid_block *block;
1278 struct wmi_block *wblock;
1279 bool found_it = false;
1280
1281 list_for_each_entry(wblock, &wmi_block_list, list) {
1282 block = &wblock->gblock;
1283
1284 if (wblock->acpi_device->handle == handle &&
1285 (block->flags & ACPI_WMI_EVENT) &&
1286 (block->notify_id == event))
1287 {
1288 found_it = true;
1289 break;
1290 }
1291 }
1292
1293 if (!found_it)
1294 return;
1295
1296 /* If a driver is bound, then notify the driver. */
1297 if (wblock->dev.dev.driver) {
1298 struct wmi_driver *driver;
1299 struct acpi_object_list input;
1300 union acpi_object params[1];
1301 struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1302 acpi_status status;
1303
1304 driver = container_of(wblock->dev.dev.driver,
1305 struct wmi_driver, driver);
1306
1307 input.count = 1;
1308 input.pointer = params;
1309 params[0].type = ACPI_TYPE_INTEGER;
1310 params[0].integer.value = event;
1311
1312 status = acpi_evaluate_object(wblock->acpi_device->handle,
1313 "_WED", &input, &evdata);
1314 if (ACPI_FAILURE(status)) {
1315 dev_warn(&wblock->dev.dev,
1316 "failed to get event data\n");
1317 return;
1318 }
1319
1320 if (driver->notify)
1321 driver->notify(&wblock->dev,
1322 (union acpi_object *)evdata.pointer);
1323
1324 kfree(evdata.pointer);
1325 } else if (wblock->handler) {
1326 /* Legacy handler */
1327 wblock->handler(event, wblock->handler_data);
1328 }
1329
1330 if (debug_event) {
1331 pr_info("DEBUG Event GUID: %pUL\n",
1332 wblock->gblock.guid);
1333 }
1334
1335 acpi_bus_generate_netlink_event(
1336 wblock->acpi_device->pnp.device_class,
1337 dev_name(&wblock->dev.dev),
1338 event, 0);
1339
1340 }
1341
1342 static int acpi_wmi_remove(struct platform_device *device)
1343 {
1344 struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1345
1346 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1347 acpi_wmi_notify_handler);
1348 acpi_remove_address_space_handler(acpi_device->handle,
1349 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1350 wmi_free_devices(acpi_device);
1351 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1352
1353 return 0;
1354 }
1355
1356 static int acpi_wmi_probe(struct platform_device *device)
1357 {
1358 struct acpi_device *acpi_device;
1359 struct device *wmi_bus_dev;
1360 acpi_status status;
1361 int error;
1362
1363 acpi_device = ACPI_COMPANION(&device->dev);
1364 if (!acpi_device) {
1365 dev_err(&device->dev, "ACPI companion is missing\n");
1366 return -ENODEV;
1367 }
1368
1369 status = acpi_install_address_space_handler(acpi_device->handle,
1370 ACPI_ADR_SPACE_EC,
1371 &acpi_wmi_ec_space_handler,
1372 NULL, NULL);
1373 if (ACPI_FAILURE(status)) {
1374 dev_err(&device->dev, "Error installing EC region handler\n");
1375 return -ENODEV;
1376 }
1377
1378 status = acpi_install_notify_handler(acpi_device->handle,
1379 ACPI_DEVICE_NOTIFY,
1380 acpi_wmi_notify_handler,
1381 NULL);
1382 if (ACPI_FAILURE(status)) {
1383 dev_err(&device->dev, "Error installing notify handler\n");
1384 error = -ENODEV;
1385 goto err_remove_ec_handler;
1386 }
1387
1388 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1389 NULL, "wmi_bus-%s", dev_name(&device->dev));
1390 if (IS_ERR(wmi_bus_dev)) {
1391 error = PTR_ERR(wmi_bus_dev);
1392 goto err_remove_notify_handler;
1393 }
1394 dev_set_drvdata(&device->dev, wmi_bus_dev);
1395
1396 error = parse_wdg(wmi_bus_dev, acpi_device);
1397 if (error) {
1398 pr_err("Failed to parse WDG method\n");
1399 goto err_remove_busdev;
1400 }
1401
1402 return 0;
1403
1404 err_remove_busdev:
1405 device_destroy(&wmi_bus_class, MKDEV(0, 0));
1406
1407 err_remove_notify_handler:
1408 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1409 acpi_wmi_notify_handler);
1410
1411 err_remove_ec_handler:
1412 acpi_remove_address_space_handler(acpi_device->handle,
1413 ACPI_ADR_SPACE_EC,
1414 &acpi_wmi_ec_space_handler);
1415
1416 return error;
1417 }
1418
1419 int __must_check __wmi_driver_register(struct wmi_driver *driver,
1420 struct module *owner)
1421 {
1422 driver->driver.owner = owner;
1423 driver->driver.bus = &wmi_bus_type;
1424
1425 return driver_register(&driver->driver);
1426 }
1427 EXPORT_SYMBOL(__wmi_driver_register);
1428
1429 void wmi_driver_unregister(struct wmi_driver *driver)
1430 {
1431 driver_unregister(&driver->driver);
1432 }
1433 EXPORT_SYMBOL(wmi_driver_unregister);
1434
1435 static int __init acpi_wmi_init(void)
1436 {
1437 int error;
1438
1439 if (acpi_disabled)
1440 return -ENODEV;
1441
1442 error = class_register(&wmi_bus_class);
1443 if (error)
1444 return error;
1445
1446 error = bus_register(&wmi_bus_type);
1447 if (error)
1448 goto err_unreg_class;
1449
1450 error = platform_driver_register(&acpi_wmi_driver);
1451 if (error) {
1452 pr_err("Error loading mapper\n");
1453 goto err_unreg_bus;
1454 }
1455
1456 return 0;
1457
1458 err_unreg_bus:
1459 bus_unregister(&wmi_bus_type);
1460
1461 err_unreg_class:
1462 class_unregister(&wmi_bus_class);
1463
1464 return error;
1465 }
1466
1467 static void __exit acpi_wmi_exit(void)
1468 {
1469 platform_driver_unregister(&acpi_wmi_driver);
1470 bus_unregister(&wmi_bus_type);
1471 class_unregister(&wmi_bus_class);
1472 }
1473
1474 subsys_initcall_sync(acpi_wmi_init);
1475 module_exit(acpi_wmi_exit);
Linux with added FPC-III support