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