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/module.h> |
27 | #include <linux/platform_device.h> |
28 | #include <linux/rwsem.h> |
29 | #include <linux/slab.h> |
30 | #include <linux/sysfs.h> |
31 | #include <linux/types.h> |
32 | #include <linux/uuid.h> |
33 | #include <linux/wmi.h> |
34 | #include <linux/fs.h> |
35 | |
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 | guid_t guid; |
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 | } __packed; |
54 | static_assert(sizeof(typeof_member(struct guid_block, guid)) == 16); |
55 | static_assert(sizeof(struct guid_block) == 20); |
56 | static_assert(__alignof__(struct guid_block) == 1); |
57 | |
58 | enum { /* wmi_block flags */ |
59 | WMI_READ_TAKES_NO_ARGS, |
60 | WMI_GUID_DUPLICATED, |
61 | WMI_NO_EVENT_DATA, |
62 | }; |
63 | |
64 | struct wmi_block { |
65 | struct wmi_device dev; |
66 | struct list_head list; |
67 | struct guid_block gblock; |
68 | struct acpi_device *acpi_device; |
69 | struct rw_semaphore notify_lock; /* Protects notify callback add/remove */ |
70 | wmi_notify_handler handler; |
71 | void *handler_data; |
72 | bool driver_ready; |
73 | unsigned long flags; |
74 | }; |
75 | |
76 | |
77 | /* |
78 | * If the GUID data block is marked as expensive, we must enable and |
79 | * explicitily disable data collection. |
80 | */ |
81 | #define ACPI_WMI_EXPENSIVE BIT(0) |
82 | #define ACPI_WMI_METHOD BIT(1) /* GUID is a method */ |
83 | #define ACPI_WMI_STRING BIT(2) /* GUID takes & returns a string */ |
84 | #define ACPI_WMI_EVENT BIT(3) /* GUID is an event */ |
85 | |
86 | static const struct acpi_device_id wmi_device_ids[] = { |
87 | {"PNP0C14" , 0}, |
88 | {"pnp0c14" , 0}, |
89 | { } |
90 | }; |
91 | MODULE_DEVICE_TABLE(acpi, wmi_device_ids); |
92 | |
93 | #define dev_to_wblock(__dev) container_of_const(__dev, struct wmi_block, dev.dev) |
94 | #define dev_to_wdev(__dev) container_of_const(__dev, struct wmi_device, dev) |
95 | |
96 | /* |
97 | * GUID parsing functions |
98 | */ |
99 | |
100 | static bool guid_parse_and_compare(const char *string, const guid_t *guid) |
101 | { |
102 | guid_t guid_input; |
103 | |
104 | if (guid_parse(uuid: string, u: &guid_input)) |
105 | return false; |
106 | |
107 | return guid_equal(u1: &guid_input, u2: guid); |
108 | } |
109 | |
110 | static const void *find_guid_context(struct wmi_block *wblock, |
111 | struct wmi_driver *wdriver) |
112 | { |
113 | const struct wmi_device_id *id; |
114 | |
115 | id = wdriver->id_table; |
116 | if (!id) |
117 | return NULL; |
118 | |
119 | while (*id->guid_string) { |
120 | if (guid_parse_and_compare(string: id->guid_string, guid: &wblock->gblock.guid)) |
121 | return id->context; |
122 | id++; |
123 | } |
124 | return NULL; |
125 | } |
126 | |
127 | static acpi_status wmi_method_enable(struct wmi_block *wblock, bool enable) |
128 | { |
129 | struct guid_block *block; |
130 | char method[5]; |
131 | acpi_status status; |
132 | acpi_handle handle; |
133 | |
134 | block = &wblock->gblock; |
135 | handle = wblock->acpi_device->handle; |
136 | |
137 | snprintf(buf: method, size: 5, fmt: "WE%02X" , block->notify_id); |
138 | status = acpi_execute_simple_method(handle, method, arg: enable); |
139 | if (status == AE_NOT_FOUND) |
140 | return AE_OK; |
141 | |
142 | return status; |
143 | } |
144 | |
145 | #define WMI_ACPI_METHOD_NAME_SIZE 5 |
146 | |
147 | static inline void get_acpi_method_name(const struct wmi_block *wblock, |
148 | const char method, |
149 | char buffer[static WMI_ACPI_METHOD_NAME_SIZE]) |
150 | { |
151 | static_assert(ARRAY_SIZE(wblock->gblock.object_id) == 2); |
152 | static_assert(WMI_ACPI_METHOD_NAME_SIZE >= 5); |
153 | |
154 | buffer[0] = 'W'; |
155 | buffer[1] = method; |
156 | buffer[2] = wblock->gblock.object_id[0]; |
157 | buffer[3] = wblock->gblock.object_id[1]; |
158 | buffer[4] = '\0'; |
159 | } |
160 | |
161 | static inline acpi_object_type get_param_acpi_type(const struct wmi_block *wblock) |
162 | { |
163 | if (wblock->gblock.flags & ACPI_WMI_STRING) |
164 | return ACPI_TYPE_STRING; |
165 | else |
166 | return ACPI_TYPE_BUFFER; |
167 | } |
168 | |
169 | static acpi_status get_event_data(const struct wmi_block *wblock, struct acpi_buffer *out) |
170 | { |
171 | union acpi_object param = { |
172 | .integer = { |
173 | .type = ACPI_TYPE_INTEGER, |
174 | .value = wblock->gblock.notify_id, |
175 | } |
176 | }; |
177 | struct acpi_object_list input = { |
178 | .count = 1, |
179 | .pointer = ¶m, |
180 | }; |
181 | |
182 | return acpi_evaluate_object(object: wblock->acpi_device->handle, pathname: "_WED" , parameter_objects: &input, return_object_buffer: out); |
183 | } |
184 | |
185 | static int wmidev_match_guid(struct device *dev, const void *data) |
186 | { |
187 | struct wmi_block *wblock = dev_to_wblock(dev); |
188 | const guid_t *guid = data; |
189 | |
190 | /* Legacy GUID-based functions are restricted to only see |
191 | * a single WMI device for each GUID. |
192 | */ |
193 | if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags)) |
194 | return 0; |
195 | |
196 | if (guid_equal(u1: guid, u2: &wblock->gblock.guid)) |
197 | return 1; |
198 | |
199 | return 0; |
200 | } |
201 | |
202 | static int wmidev_match_notify_id(struct device *dev, const void *data) |
203 | { |
204 | struct wmi_block *wblock = dev_to_wblock(dev); |
205 | const u32 *notify_id = data; |
206 | |
207 | /* Legacy GUID-based functions are restricted to only see |
208 | * a single WMI device for each GUID. |
209 | */ |
210 | if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags)) |
211 | return 0; |
212 | |
213 | if (wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *notify_id) |
214 | return 1; |
215 | |
216 | return 0; |
217 | } |
218 | |
219 | static const struct bus_type wmi_bus_type; |
220 | |
221 | static struct wmi_device *wmi_find_device_by_guid(const char *guid_string) |
222 | { |
223 | struct device *dev; |
224 | guid_t guid; |
225 | int ret; |
226 | |
227 | ret = guid_parse(uuid: guid_string, u: &guid); |
228 | if (ret < 0) |
229 | return ERR_PTR(error: ret); |
230 | |
231 | dev = bus_find_device(bus: &wmi_bus_type, NULL, data: &guid, match: wmidev_match_guid); |
232 | if (!dev) |
233 | return ERR_PTR(error: -ENODEV); |
234 | |
235 | return dev_to_wdev(dev); |
236 | } |
237 | |
238 | static struct wmi_device *wmi_find_event_by_notify_id(const u32 notify_id) |
239 | { |
240 | struct device *dev; |
241 | |
242 | dev = bus_find_device(bus: &wmi_bus_type, NULL, data: ¬ify_id, match: wmidev_match_notify_id); |
243 | if (!dev) |
244 | return ERR_PTR(error: -ENODEV); |
245 | |
246 | return to_wmi_device(dev); |
247 | } |
248 | |
249 | static void wmi_device_put(struct wmi_device *wdev) |
250 | { |
251 | put_device(dev: &wdev->dev); |
252 | } |
253 | |
254 | /* |
255 | * Exported WMI functions |
256 | */ |
257 | |
258 | /** |
259 | * wmi_instance_count - Get number of WMI object instances |
260 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
261 | * |
262 | * Get the number of WMI object instances. |
263 | * |
264 | * Returns: Number of WMI object instances or negative error code. |
265 | */ |
266 | int wmi_instance_count(const char *guid_string) |
267 | { |
268 | struct wmi_device *wdev; |
269 | int ret; |
270 | |
271 | wdev = wmi_find_device_by_guid(guid_string); |
272 | if (IS_ERR(ptr: wdev)) |
273 | return PTR_ERR(ptr: wdev); |
274 | |
275 | ret = wmidev_instance_count(wdev); |
276 | wmi_device_put(wdev); |
277 | |
278 | return ret; |
279 | } |
280 | EXPORT_SYMBOL_GPL(wmi_instance_count); |
281 | |
282 | /** |
283 | * wmidev_instance_count - Get number of WMI object instances |
284 | * @wdev: A wmi bus device from a driver |
285 | * |
286 | * Get the number of WMI object instances. |
287 | * |
288 | * Returns: Number of WMI object instances. |
289 | */ |
290 | u8 wmidev_instance_count(struct wmi_device *wdev) |
291 | { |
292 | struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); |
293 | |
294 | return wblock->gblock.instance_count; |
295 | } |
296 | EXPORT_SYMBOL_GPL(wmidev_instance_count); |
297 | |
298 | /** |
299 | * wmi_evaluate_method - Evaluate a WMI method (deprecated) |
300 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
301 | * @instance: Instance index |
302 | * @method_id: Method ID to call |
303 | * @in: Mandatory buffer containing input for the method call |
304 | * @out: Empty buffer to return the method results |
305 | * |
306 | * Call an ACPI-WMI method, the caller must free @out. |
307 | * |
308 | * Return: acpi_status signaling success or error. |
309 | */ |
310 | acpi_status wmi_evaluate_method(const char *guid_string, u8 instance, u32 method_id, |
311 | const struct acpi_buffer *in, struct acpi_buffer *out) |
312 | { |
313 | struct wmi_device *wdev; |
314 | acpi_status status; |
315 | |
316 | wdev = wmi_find_device_by_guid(guid_string); |
317 | if (IS_ERR(ptr: wdev)) |
318 | return AE_ERROR; |
319 | |
320 | status = wmidev_evaluate_method(wdev, instance, method_id, in, out); |
321 | |
322 | wmi_device_put(wdev); |
323 | |
324 | return status; |
325 | } |
326 | EXPORT_SYMBOL_GPL(wmi_evaluate_method); |
327 | |
328 | /** |
329 | * wmidev_evaluate_method - Evaluate a WMI method |
330 | * @wdev: A wmi bus device from a driver |
331 | * @instance: Instance index |
332 | * @method_id: Method ID to call |
333 | * @in: Mandatory buffer containing input for the method call |
334 | * @out: Empty buffer to return the method results |
335 | * |
336 | * Call an ACPI-WMI method, the caller must free @out. |
337 | * |
338 | * Return: acpi_status signaling success or error. |
339 | */ |
340 | acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance, u32 method_id, |
341 | const struct acpi_buffer *in, struct acpi_buffer *out) |
342 | { |
343 | struct guid_block *block; |
344 | struct wmi_block *wblock; |
345 | acpi_handle handle; |
346 | struct acpi_object_list input; |
347 | union acpi_object params[3]; |
348 | char method[WMI_ACPI_METHOD_NAME_SIZE]; |
349 | |
350 | wblock = container_of(wdev, struct wmi_block, dev); |
351 | block = &wblock->gblock; |
352 | handle = wblock->acpi_device->handle; |
353 | |
354 | if (!in) |
355 | return AE_BAD_DATA; |
356 | |
357 | if (!(block->flags & ACPI_WMI_METHOD)) |
358 | return AE_BAD_DATA; |
359 | |
360 | if (block->instance_count <= instance) |
361 | return AE_BAD_PARAMETER; |
362 | |
363 | input.count = 3; |
364 | input.pointer = params; |
365 | |
366 | params[0].type = ACPI_TYPE_INTEGER; |
367 | params[0].integer.value = instance; |
368 | params[1].type = ACPI_TYPE_INTEGER; |
369 | params[1].integer.value = method_id; |
370 | params[2].type = get_param_acpi_type(wblock); |
371 | params[2].buffer.length = in->length; |
372 | params[2].buffer.pointer = in->pointer; |
373 | |
374 | get_acpi_method_name(wblock, method: 'M', buffer: method); |
375 | |
376 | return acpi_evaluate_object(object: handle, pathname: method, parameter_objects: &input, return_object_buffer: out); |
377 | } |
378 | EXPORT_SYMBOL_GPL(wmidev_evaluate_method); |
379 | |
380 | static acpi_status __query_block(struct wmi_block *wblock, u8 instance, |
381 | struct acpi_buffer *out) |
382 | { |
383 | struct guid_block *block; |
384 | acpi_handle handle; |
385 | acpi_status status, wc_status = AE_ERROR; |
386 | struct acpi_object_list input; |
387 | union acpi_object wq_params[1]; |
388 | char wc_method[WMI_ACPI_METHOD_NAME_SIZE]; |
389 | char method[WMI_ACPI_METHOD_NAME_SIZE]; |
390 | |
391 | if (!out) |
392 | return AE_BAD_PARAMETER; |
393 | |
394 | block = &wblock->gblock; |
395 | handle = wblock->acpi_device->handle; |
396 | |
397 | if (block->instance_count <= instance) |
398 | return AE_BAD_PARAMETER; |
399 | |
400 | /* Check GUID is a data block */ |
401 | if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD)) |
402 | return AE_ERROR; |
403 | |
404 | input.count = 1; |
405 | input.pointer = wq_params; |
406 | wq_params[0].type = ACPI_TYPE_INTEGER; |
407 | wq_params[0].integer.value = instance; |
408 | |
409 | if (instance == 0 && test_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags)) |
410 | input.count = 0; |
411 | |
412 | /* |
413 | * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to |
414 | * enable collection. |
415 | */ |
416 | if (block->flags & ACPI_WMI_EXPENSIVE) { |
417 | get_acpi_method_name(wblock, method: 'C', buffer: wc_method); |
418 | |
419 | /* |
420 | * Some GUIDs break the specification by declaring themselves |
421 | * expensive, but have no corresponding WCxx method. So we |
422 | * should not fail if this happens. |
423 | */ |
424 | wc_status = acpi_execute_simple_method(handle, method: wc_method, arg: 1); |
425 | } |
426 | |
427 | get_acpi_method_name(wblock, method: 'Q', buffer: method); |
428 | status = acpi_evaluate_object(object: handle, pathname: method, parameter_objects: &input, return_object_buffer: out); |
429 | |
430 | /* |
431 | * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if |
432 | * the WQxx method failed - we should disable collection anyway. |
433 | */ |
434 | if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) { |
435 | /* |
436 | * Ignore whether this WCxx call succeeds or not since |
437 | * the previously executed WQxx method call might have |
438 | * succeeded, and returning the failing status code |
439 | * of this call would throw away the result of the WQxx |
440 | * call, potentially leaking memory. |
441 | */ |
442 | acpi_execute_simple_method(handle, method: wc_method, arg: 0); |
443 | } |
444 | |
445 | return status; |
446 | } |
447 | |
448 | /** |
449 | * wmi_query_block - Return contents of a WMI block (deprecated) |
450 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
451 | * @instance: Instance index |
452 | * @out: Empty buffer to return the contents of the data block to |
453 | * |
454 | * Query a ACPI-WMI block, the caller must free @out. |
455 | * |
456 | * Return: ACPI object containing the content of the WMI block. |
457 | */ |
458 | acpi_status wmi_query_block(const char *guid_string, u8 instance, |
459 | struct acpi_buffer *out) |
460 | { |
461 | struct wmi_block *wblock; |
462 | struct wmi_device *wdev; |
463 | acpi_status status; |
464 | |
465 | wdev = wmi_find_device_by_guid(guid_string); |
466 | if (IS_ERR(ptr: wdev)) |
467 | return AE_ERROR; |
468 | |
469 | wblock = container_of(wdev, struct wmi_block, dev); |
470 | status = __query_block(wblock, instance, out); |
471 | |
472 | wmi_device_put(wdev); |
473 | |
474 | return status; |
475 | } |
476 | EXPORT_SYMBOL_GPL(wmi_query_block); |
477 | |
478 | /** |
479 | * wmidev_block_query - Return contents of a WMI block |
480 | * @wdev: A wmi bus device from a driver |
481 | * @instance: Instance index |
482 | * |
483 | * Query an ACPI-WMI block, the caller must free the result. |
484 | * |
485 | * Return: ACPI object containing the content of the WMI block. |
486 | */ |
487 | union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance) |
488 | { |
489 | struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL }; |
490 | struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); |
491 | |
492 | if (ACPI_FAILURE(__query_block(wblock, instance, &out))) |
493 | return NULL; |
494 | |
495 | return out.pointer; |
496 | } |
497 | EXPORT_SYMBOL_GPL(wmidev_block_query); |
498 | |
499 | /** |
500 | * wmi_set_block - Write to a WMI block (deprecated) |
501 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
502 | * @instance: Instance index |
503 | * @in: Buffer containing new values for the data block |
504 | * |
505 | * Write the contents of the input buffer to an ACPI-WMI data block. |
506 | * |
507 | * Return: acpi_status signaling success or error. |
508 | */ |
509 | acpi_status wmi_set_block(const char *guid_string, u8 instance, const struct acpi_buffer *in) |
510 | { |
511 | struct wmi_device *wdev; |
512 | acpi_status status; |
513 | |
514 | wdev = wmi_find_device_by_guid(guid_string); |
515 | if (IS_ERR(ptr: wdev)) |
516 | return AE_ERROR; |
517 | |
518 | status = wmidev_block_set(wdev, instance, in); |
519 | wmi_device_put(wdev); |
520 | |
521 | return status; |
522 | } |
523 | EXPORT_SYMBOL_GPL(wmi_set_block); |
524 | |
525 | /** |
526 | * wmidev_block_set - Write to a WMI block |
527 | * @wdev: A wmi bus device from a driver |
528 | * @instance: Instance index |
529 | * @in: Buffer containing new values for the data block |
530 | * |
531 | * Write contents of the input buffer to an ACPI-WMI data block. |
532 | * |
533 | * Return: acpi_status signaling success or error. |
534 | */ |
535 | acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in) |
536 | { |
537 | struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev); |
538 | acpi_handle handle = wblock->acpi_device->handle; |
539 | struct guid_block *block = &wblock->gblock; |
540 | char method[WMI_ACPI_METHOD_NAME_SIZE]; |
541 | struct acpi_object_list input; |
542 | union acpi_object params[2]; |
543 | |
544 | if (!in) |
545 | return AE_BAD_DATA; |
546 | |
547 | if (block->instance_count <= instance) |
548 | return AE_BAD_PARAMETER; |
549 | |
550 | /* Check GUID is a data block */ |
551 | if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD)) |
552 | return AE_ERROR; |
553 | |
554 | input.count = 2; |
555 | input.pointer = params; |
556 | params[0].type = ACPI_TYPE_INTEGER; |
557 | params[0].integer.value = instance; |
558 | params[1].type = get_param_acpi_type(wblock); |
559 | params[1].buffer.length = in->length; |
560 | params[1].buffer.pointer = in->pointer; |
561 | |
562 | get_acpi_method_name(wblock, method: 'S', buffer: method); |
563 | |
564 | return acpi_evaluate_object(object: handle, pathname: method, parameter_objects: &input, NULL); |
565 | } |
566 | EXPORT_SYMBOL_GPL(wmidev_block_set); |
567 | |
568 | /** |
569 | * wmi_install_notify_handler - Register handler for WMI events (deprecated) |
570 | * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
571 | * @handler: Function to handle notifications |
572 | * @data: Data to be returned to handler when event is fired |
573 | * |
574 | * Register a handler for events sent to the ACPI-WMI mapper device. |
575 | * |
576 | * Return: acpi_status signaling success or error. |
577 | */ |
578 | acpi_status wmi_install_notify_handler(const char *guid, |
579 | wmi_notify_handler handler, |
580 | void *data) |
581 | { |
582 | struct wmi_block *wblock; |
583 | struct wmi_device *wdev; |
584 | acpi_status status; |
585 | |
586 | wdev = wmi_find_device_by_guid(guid_string: guid); |
587 | if (IS_ERR(ptr: wdev)) |
588 | return AE_ERROR; |
589 | |
590 | wblock = container_of(wdev, struct wmi_block, dev); |
591 | |
592 | down_write(sem: &wblock->notify_lock); |
593 | if (wblock->handler) { |
594 | status = AE_ALREADY_ACQUIRED; |
595 | } else { |
596 | wblock->handler = handler; |
597 | wblock->handler_data = data; |
598 | |
599 | if (ACPI_FAILURE(wmi_method_enable(wblock, true))) |
600 | dev_warn(&wblock->dev.dev, "Failed to enable device\n" ); |
601 | |
602 | status = AE_OK; |
603 | } |
604 | up_write(sem: &wblock->notify_lock); |
605 | |
606 | wmi_device_put(wdev); |
607 | |
608 | return status; |
609 | } |
610 | EXPORT_SYMBOL_GPL(wmi_install_notify_handler); |
611 | |
612 | /** |
613 | * wmi_remove_notify_handler - Unregister handler for WMI events (deprecated) |
614 | * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
615 | * |
616 | * Unregister handler for events sent to the ACPI-WMI mapper device. |
617 | * |
618 | * Return: acpi_status signaling success or error. |
619 | */ |
620 | acpi_status wmi_remove_notify_handler(const char *guid) |
621 | { |
622 | struct wmi_block *wblock; |
623 | struct wmi_device *wdev; |
624 | acpi_status status; |
625 | |
626 | wdev = wmi_find_device_by_guid(guid_string: guid); |
627 | if (IS_ERR(ptr: wdev)) |
628 | return AE_ERROR; |
629 | |
630 | wblock = container_of(wdev, struct wmi_block, dev); |
631 | |
632 | down_write(sem: &wblock->notify_lock); |
633 | if (!wblock->handler) { |
634 | status = AE_NULL_ENTRY; |
635 | } else { |
636 | if (ACPI_FAILURE(wmi_method_enable(wblock, false))) |
637 | dev_warn(&wblock->dev.dev, "Failed to disable device\n" ); |
638 | |
639 | wblock->handler = NULL; |
640 | wblock->handler_data = NULL; |
641 | |
642 | status = AE_OK; |
643 | } |
644 | up_write(sem: &wblock->notify_lock); |
645 | |
646 | wmi_device_put(wdev); |
647 | |
648 | return status; |
649 | } |
650 | EXPORT_SYMBOL_GPL(wmi_remove_notify_handler); |
651 | |
652 | /** |
653 | * wmi_get_event_data - Get WMI data associated with an event (deprecated) |
654 | * |
655 | * @event: Event to find |
656 | * @out: Buffer to hold event data |
657 | * |
658 | * Get extra data associated with an WMI event, the caller needs to free @out. |
659 | * |
660 | * Return: acpi_status signaling success or error. |
661 | */ |
662 | acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out) |
663 | { |
664 | struct wmi_block *wblock; |
665 | struct wmi_device *wdev; |
666 | acpi_status status; |
667 | |
668 | wdev = wmi_find_event_by_notify_id(notify_id: event); |
669 | if (IS_ERR(ptr: wdev)) |
670 | return AE_NOT_FOUND; |
671 | |
672 | wblock = container_of(wdev, struct wmi_block, dev); |
673 | status = get_event_data(wblock, out); |
674 | |
675 | wmi_device_put(wdev); |
676 | |
677 | return status; |
678 | } |
679 | EXPORT_SYMBOL_GPL(wmi_get_event_data); |
680 | |
681 | /** |
682 | * wmi_has_guid - Check if a GUID is available |
683 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
684 | * |
685 | * Check if a given GUID is defined by _WDG. |
686 | * |
687 | * Return: True if GUID is available, false otherwise. |
688 | */ |
689 | bool wmi_has_guid(const char *guid_string) |
690 | { |
691 | struct wmi_device *wdev; |
692 | |
693 | wdev = wmi_find_device_by_guid(guid_string); |
694 | if (IS_ERR(ptr: wdev)) |
695 | return false; |
696 | |
697 | wmi_device_put(wdev); |
698 | |
699 | return true; |
700 | } |
701 | EXPORT_SYMBOL_GPL(wmi_has_guid); |
702 | |
703 | /** |
704 | * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID (deprecated) |
705 | * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba |
706 | * |
707 | * Find the _UID of ACPI device associated with this WMI GUID. |
708 | * |
709 | * Return: The ACPI _UID field value or NULL if the WMI GUID was not found. |
710 | */ |
711 | char *wmi_get_acpi_device_uid(const char *guid_string) |
712 | { |
713 | struct wmi_block *wblock; |
714 | struct wmi_device *wdev; |
715 | char *uid; |
716 | |
717 | wdev = wmi_find_device_by_guid(guid_string); |
718 | if (IS_ERR(ptr: wdev)) |
719 | return NULL; |
720 | |
721 | wblock = container_of(wdev, struct wmi_block, dev); |
722 | uid = acpi_device_uid(wblock->acpi_device); |
723 | |
724 | wmi_device_put(wdev); |
725 | |
726 | return uid; |
727 | } |
728 | EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid); |
729 | |
730 | static inline struct wmi_driver *drv_to_wdrv(struct device_driver *drv) |
731 | { |
732 | return container_of(drv, struct wmi_driver, driver); |
733 | } |
734 | |
735 | /* |
736 | * sysfs interface |
737 | */ |
738 | static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, |
739 | char *buf) |
740 | { |
741 | struct wmi_block *wblock = dev_to_wblock(dev); |
742 | |
743 | return sysfs_emit(buf, fmt: "wmi:%pUL\n" , &wblock->gblock.guid); |
744 | } |
745 | static DEVICE_ATTR_RO(modalias); |
746 | |
747 | static ssize_t guid_show(struct device *dev, struct device_attribute *attr, |
748 | char *buf) |
749 | { |
750 | struct wmi_block *wblock = dev_to_wblock(dev); |
751 | |
752 | return sysfs_emit(buf, fmt: "%pUL\n" , &wblock->gblock.guid); |
753 | } |
754 | static DEVICE_ATTR_RO(guid); |
755 | |
756 | static ssize_t instance_count_show(struct device *dev, |
757 | struct device_attribute *attr, char *buf) |
758 | { |
759 | struct wmi_block *wblock = dev_to_wblock(dev); |
760 | |
761 | return sysfs_emit(buf, fmt: "%d\n" , (int)wblock->gblock.instance_count); |
762 | } |
763 | static DEVICE_ATTR_RO(instance_count); |
764 | |
765 | static ssize_t expensive_show(struct device *dev, |
766 | struct device_attribute *attr, char *buf) |
767 | { |
768 | struct wmi_block *wblock = dev_to_wblock(dev); |
769 | |
770 | return sysfs_emit(buf, fmt: "%d\n" , |
771 | (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0); |
772 | } |
773 | static DEVICE_ATTR_RO(expensive); |
774 | |
775 | static struct attribute *wmi_attrs[] = { |
776 | &dev_attr_modalias.attr, |
777 | &dev_attr_guid.attr, |
778 | &dev_attr_instance_count.attr, |
779 | &dev_attr_expensive.attr, |
780 | NULL |
781 | }; |
782 | ATTRIBUTE_GROUPS(wmi); |
783 | |
784 | static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr, |
785 | char *buf) |
786 | { |
787 | struct wmi_block *wblock = dev_to_wblock(dev); |
788 | |
789 | return sysfs_emit(buf, fmt: "%02X\n" , (unsigned int)wblock->gblock.notify_id); |
790 | } |
791 | static DEVICE_ATTR_RO(notify_id); |
792 | |
793 | static struct attribute *wmi_event_attrs[] = { |
794 | &dev_attr_notify_id.attr, |
795 | NULL |
796 | }; |
797 | ATTRIBUTE_GROUPS(wmi_event); |
798 | |
799 | static ssize_t object_id_show(struct device *dev, struct device_attribute *attr, |
800 | char *buf) |
801 | { |
802 | struct wmi_block *wblock = dev_to_wblock(dev); |
803 | |
804 | return sysfs_emit(buf, fmt: "%c%c\n" , wblock->gblock.object_id[0], |
805 | wblock->gblock.object_id[1]); |
806 | } |
807 | static DEVICE_ATTR_RO(object_id); |
808 | |
809 | static ssize_t setable_show(struct device *dev, struct device_attribute *attr, |
810 | char *buf) |
811 | { |
812 | struct wmi_device *wdev = dev_to_wdev(dev); |
813 | |
814 | return sysfs_emit(buf, fmt: "%d\n" , (int)wdev->setable); |
815 | } |
816 | static DEVICE_ATTR_RO(setable); |
817 | |
818 | static struct attribute *wmi_data_attrs[] = { |
819 | &dev_attr_object_id.attr, |
820 | &dev_attr_setable.attr, |
821 | NULL |
822 | }; |
823 | ATTRIBUTE_GROUPS(wmi_data); |
824 | |
825 | static struct attribute *wmi_method_attrs[] = { |
826 | &dev_attr_object_id.attr, |
827 | NULL |
828 | }; |
829 | ATTRIBUTE_GROUPS(wmi_method); |
830 | |
831 | static int wmi_dev_uevent(const struct device *dev, struct kobj_uevent_env *env) |
832 | { |
833 | const struct wmi_block *wblock = dev_to_wblock(dev); |
834 | |
835 | if (add_uevent_var(env, format: "MODALIAS=wmi:%pUL" , &wblock->gblock.guid)) |
836 | return -ENOMEM; |
837 | |
838 | if (add_uevent_var(env, format: "WMI_GUID=%pUL" , &wblock->gblock.guid)) |
839 | return -ENOMEM; |
840 | |
841 | return 0; |
842 | } |
843 | |
844 | static void wmi_dev_release(struct device *dev) |
845 | { |
846 | struct wmi_block *wblock = dev_to_wblock(dev); |
847 | |
848 | kfree(objp: wblock); |
849 | } |
850 | |
851 | static int wmi_dev_match(struct device *dev, struct device_driver *driver) |
852 | { |
853 | struct wmi_driver *wmi_driver = drv_to_wdrv(drv: driver); |
854 | struct wmi_block *wblock = dev_to_wblock(dev); |
855 | const struct wmi_device_id *id = wmi_driver->id_table; |
856 | |
857 | if (id == NULL) |
858 | return 0; |
859 | |
860 | while (*id->guid_string) { |
861 | if (guid_parse_and_compare(string: id->guid_string, guid: &wblock->gblock.guid)) |
862 | return 1; |
863 | |
864 | id++; |
865 | } |
866 | |
867 | return 0; |
868 | } |
869 | |
870 | static int wmi_dev_probe(struct device *dev) |
871 | { |
872 | struct wmi_block *wblock = dev_to_wblock(dev); |
873 | struct wmi_driver *wdriver = drv_to_wdrv(drv: dev->driver); |
874 | int ret = 0; |
875 | |
876 | /* Some older WMI drivers will break if instantiated multiple times, |
877 | * so they are blocked from probing WMI devices with a duplicated GUID. |
878 | * |
879 | * New WMI drivers should support being instantiated multiple times. |
880 | */ |
881 | if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags) && !wdriver->no_singleton) { |
882 | dev_warn(dev, "Legacy driver %s cannot be instantiated multiple times\n" , |
883 | dev->driver->name); |
884 | |
885 | return -ENODEV; |
886 | } |
887 | |
888 | if (wdriver->notify) { |
889 | if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags) && !wdriver->no_notify_data) |
890 | return -ENODEV; |
891 | } |
892 | |
893 | if (ACPI_FAILURE(wmi_method_enable(wblock, true))) |
894 | dev_warn(dev, "failed to enable device -- probing anyway\n" ); |
895 | |
896 | if (wdriver->probe) { |
897 | ret = wdriver->probe(dev_to_wdev(dev), |
898 | find_guid_context(wblock, wdriver)); |
899 | if (ret) { |
900 | if (ACPI_FAILURE(wmi_method_enable(wblock, false))) |
901 | dev_warn(dev, "Failed to disable device\n" ); |
902 | |
903 | return ret; |
904 | } |
905 | } |
906 | |
907 | down_write(sem: &wblock->notify_lock); |
908 | wblock->driver_ready = true; |
909 | up_write(sem: &wblock->notify_lock); |
910 | |
911 | return 0; |
912 | } |
913 | |
914 | static void wmi_dev_remove(struct device *dev) |
915 | { |
916 | struct wmi_block *wblock = dev_to_wblock(dev); |
917 | struct wmi_driver *wdriver = drv_to_wdrv(drv: dev->driver); |
918 | |
919 | down_write(sem: &wblock->notify_lock); |
920 | wblock->driver_ready = false; |
921 | up_write(sem: &wblock->notify_lock); |
922 | |
923 | if (wdriver->remove) |
924 | wdriver->remove(dev_to_wdev(dev)); |
925 | |
926 | if (ACPI_FAILURE(wmi_method_enable(wblock, false))) |
927 | dev_warn(dev, "failed to disable device\n" ); |
928 | } |
929 | |
930 | static struct class wmi_bus_class = { |
931 | .name = "wmi_bus" , |
932 | }; |
933 | |
934 | static const struct bus_type wmi_bus_type = { |
935 | .name = "wmi" , |
936 | .dev_groups = wmi_groups, |
937 | .match = wmi_dev_match, |
938 | .uevent = wmi_dev_uevent, |
939 | .probe = wmi_dev_probe, |
940 | .remove = wmi_dev_remove, |
941 | }; |
942 | |
943 | static const struct device_type wmi_type_event = { |
944 | .name = "event" , |
945 | .groups = wmi_event_groups, |
946 | .release = wmi_dev_release, |
947 | }; |
948 | |
949 | static const struct device_type wmi_type_method = { |
950 | .name = "method" , |
951 | .groups = wmi_method_groups, |
952 | .release = wmi_dev_release, |
953 | }; |
954 | |
955 | static const struct device_type wmi_type_data = { |
956 | .name = "data" , |
957 | .groups = wmi_data_groups, |
958 | .release = wmi_dev_release, |
959 | }; |
960 | |
961 | /* |
962 | * _WDG is a static list that is only parsed at startup, |
963 | * so it's safe to count entries without extra protection. |
964 | */ |
965 | static int guid_count(const guid_t *guid) |
966 | { |
967 | struct wmi_block *wblock; |
968 | int count = 0; |
969 | |
970 | list_for_each_entry(wblock, &wmi_block_list, list) { |
971 | if (guid_equal(u1: &wblock->gblock.guid, u2: guid)) |
972 | count++; |
973 | } |
974 | |
975 | return count; |
976 | } |
977 | |
978 | static int wmi_create_device(struct device *wmi_bus_dev, |
979 | struct wmi_block *wblock, |
980 | struct acpi_device *device) |
981 | { |
982 | char method[WMI_ACPI_METHOD_NAME_SIZE]; |
983 | struct acpi_device_info *info; |
984 | acpi_handle method_handle; |
985 | acpi_status status; |
986 | uint count; |
987 | |
988 | if (wblock->gblock.flags & ACPI_WMI_EVENT) { |
989 | wblock->dev.dev.type = &wmi_type_event; |
990 | goto out_init; |
991 | } |
992 | |
993 | if (wblock->gblock.flags & ACPI_WMI_METHOD) { |
994 | get_acpi_method_name(wblock, method: 'M', buffer: method); |
995 | if (!acpi_has_method(handle: device->handle, name: method)) { |
996 | dev_warn(wmi_bus_dev, |
997 | FW_BUG "%s method block execution control method not found\n" , |
998 | method); |
999 | |
1000 | return -ENXIO; |
1001 | } |
1002 | |
1003 | wblock->dev.dev.type = &wmi_type_method; |
1004 | goto out_init; |
1005 | } |
1006 | |
1007 | /* |
1008 | * Data Block Query Control Method (WQxx by convention) is |
1009 | * required per the WMI documentation. If it is not present, |
1010 | * we ignore this data block. |
1011 | */ |
1012 | get_acpi_method_name(wblock, method: 'Q', buffer: method); |
1013 | status = acpi_get_handle(parent: device->handle, pathname: method, ret_handle: &method_handle); |
1014 | if (ACPI_FAILURE(status)) { |
1015 | dev_warn(wmi_bus_dev, |
1016 | FW_BUG "%s data block query control method not found\n" , |
1017 | method); |
1018 | |
1019 | return -ENXIO; |
1020 | } |
1021 | |
1022 | status = acpi_get_object_info(object: method_handle, return_buffer: &info); |
1023 | if (ACPI_FAILURE(status)) |
1024 | return -EIO; |
1025 | |
1026 | wblock->dev.dev.type = &wmi_type_data; |
1027 | |
1028 | /* |
1029 | * The Microsoft documentation specifically states: |
1030 | * |
1031 | * Data blocks registered with only a single instance |
1032 | * can ignore the parameter. |
1033 | * |
1034 | * ACPICA will get mad at us if we call the method with the wrong number |
1035 | * of arguments, so check what our method expects. (On some Dell |
1036 | * laptops, WQxx may not be a method at all.) |
1037 | */ |
1038 | if (info->type != ACPI_TYPE_METHOD || info->param_count == 0) |
1039 | set_bit(nr: WMI_READ_TAKES_NO_ARGS, addr: &wblock->flags); |
1040 | |
1041 | kfree(objp: info); |
1042 | |
1043 | get_acpi_method_name(wblock, method: 'S', buffer: method); |
1044 | if (acpi_has_method(handle: device->handle, name: method)) |
1045 | wblock->dev.setable = true; |
1046 | |
1047 | out_init: |
1048 | init_rwsem(&wblock->notify_lock); |
1049 | wblock->driver_ready = false; |
1050 | wblock->dev.dev.bus = &wmi_bus_type; |
1051 | wblock->dev.dev.parent = wmi_bus_dev; |
1052 | |
1053 | count = guid_count(guid: &wblock->gblock.guid); |
1054 | if (count) { |
1055 | dev_set_name(dev: &wblock->dev.dev, name: "%pUL-%d" , &wblock->gblock.guid, count); |
1056 | set_bit(nr: WMI_GUID_DUPLICATED, addr: &wblock->flags); |
1057 | } else { |
1058 | dev_set_name(dev: &wblock->dev.dev, name: "%pUL" , &wblock->gblock.guid); |
1059 | } |
1060 | |
1061 | device_initialize(dev: &wblock->dev.dev); |
1062 | |
1063 | return 0; |
1064 | } |
1065 | |
1066 | static int wmi_add_device(struct platform_device *pdev, struct wmi_device *wdev) |
1067 | { |
1068 | struct device_link *link; |
1069 | |
1070 | /* |
1071 | * Many aggregate WMI drivers do not use -EPROBE_DEFER when they |
1072 | * are unable to find a WMI device during probe, instead they require |
1073 | * all WMI devices associated with an platform device to become available |
1074 | * at once. This device link thus prevents WMI drivers from probing until |
1075 | * the associated platform device has finished probing (and has registered |
1076 | * all discovered WMI devices). |
1077 | */ |
1078 | |
1079 | link = device_link_add(consumer: &wdev->dev, supplier: &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER); |
1080 | if (!link) |
1081 | return -EINVAL; |
1082 | |
1083 | return device_add(dev: &wdev->dev); |
1084 | } |
1085 | |
1086 | /* |
1087 | * Parse the _WDG method for the GUID data blocks |
1088 | */ |
1089 | static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev) |
1090 | { |
1091 | struct acpi_device *device = ACPI_COMPANION(&pdev->dev); |
1092 | struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL}; |
1093 | const struct guid_block *gblock; |
1094 | bool event_data_available; |
1095 | struct wmi_block *wblock; |
1096 | union acpi_object *obj; |
1097 | acpi_status status; |
1098 | u32 i, total; |
1099 | int retval; |
1100 | |
1101 | status = acpi_evaluate_object(object: device->handle, pathname: "_WDG" , NULL, return_object_buffer: &out); |
1102 | if (ACPI_FAILURE(status)) |
1103 | return -ENXIO; |
1104 | |
1105 | obj = out.pointer; |
1106 | if (!obj) |
1107 | return -ENXIO; |
1108 | |
1109 | if (obj->type != ACPI_TYPE_BUFFER) { |
1110 | kfree(objp: obj); |
1111 | return -ENXIO; |
1112 | } |
1113 | |
1114 | event_data_available = acpi_has_method(handle: device->handle, name: "_WED" ); |
1115 | gblock = (const struct guid_block *)obj->buffer.pointer; |
1116 | total = obj->buffer.length / sizeof(struct guid_block); |
1117 | |
1118 | for (i = 0; i < total; i++) { |
1119 | if (!gblock[i].instance_count) { |
1120 | dev_info(wmi_bus_dev, FW_INFO "%pUL has zero instances\n" , &gblock[i].guid); |
1121 | continue; |
1122 | } |
1123 | |
1124 | wblock = kzalloc(size: sizeof(*wblock), GFP_KERNEL); |
1125 | if (!wblock) |
1126 | continue; |
1127 | |
1128 | wblock->acpi_device = device; |
1129 | wblock->gblock = gblock[i]; |
1130 | if (gblock[i].flags & ACPI_WMI_EVENT && !event_data_available) |
1131 | set_bit(nr: WMI_NO_EVENT_DATA, addr: &wblock->flags); |
1132 | |
1133 | retval = wmi_create_device(wmi_bus_dev, wblock, device); |
1134 | if (retval) { |
1135 | kfree(objp: wblock); |
1136 | continue; |
1137 | } |
1138 | |
1139 | list_add_tail(new: &wblock->list, head: &wmi_block_list); |
1140 | |
1141 | retval = wmi_add_device(pdev, wdev: &wblock->dev); |
1142 | if (retval) { |
1143 | dev_err(wmi_bus_dev, "failed to register %pUL\n" , |
1144 | &wblock->gblock.guid); |
1145 | |
1146 | list_del(entry: &wblock->list); |
1147 | put_device(dev: &wblock->dev.dev); |
1148 | } |
1149 | } |
1150 | |
1151 | kfree(objp: obj); |
1152 | |
1153 | return 0; |
1154 | } |
1155 | |
1156 | /* |
1157 | * WMI can have EmbeddedControl access regions. In which case, we just want to |
1158 | * hand these off to the EC driver. |
1159 | */ |
1160 | static acpi_status |
1161 | acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address, |
1162 | u32 bits, u64 *value, |
1163 | void *handler_context, void *region_context) |
1164 | { |
1165 | int result = 0; |
1166 | u8 temp = 0; |
1167 | |
1168 | if ((address > 0xFF) || !value) |
1169 | return AE_BAD_PARAMETER; |
1170 | |
1171 | if (function != ACPI_READ && function != ACPI_WRITE) |
1172 | return AE_BAD_PARAMETER; |
1173 | |
1174 | if (bits != 8) |
1175 | return AE_BAD_PARAMETER; |
1176 | |
1177 | if (function == ACPI_READ) { |
1178 | result = ec_read(addr: address, val: &temp); |
1179 | *value = temp; |
1180 | } else { |
1181 | temp = 0xff & *value; |
1182 | result = ec_write(addr: address, val: temp); |
1183 | } |
1184 | |
1185 | switch (result) { |
1186 | case -EINVAL: |
1187 | return AE_BAD_PARAMETER; |
1188 | case -ENODEV: |
1189 | return AE_NOT_FOUND; |
1190 | case -ETIME: |
1191 | return AE_TIME; |
1192 | default: |
1193 | return AE_OK; |
1194 | } |
1195 | } |
1196 | |
1197 | static int wmi_get_notify_data(struct wmi_block *wblock, union acpi_object **obj) |
1198 | { |
1199 | struct acpi_buffer data = { ACPI_ALLOCATE_BUFFER, NULL }; |
1200 | acpi_status status; |
1201 | |
1202 | if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags)) { |
1203 | *obj = NULL; |
1204 | return 0; |
1205 | } |
1206 | |
1207 | status = get_event_data(wblock, out: &data); |
1208 | if (ACPI_FAILURE(status)) { |
1209 | dev_warn(&wblock->dev.dev, "Failed to get event data\n" ); |
1210 | return -EIO; |
1211 | } |
1212 | |
1213 | *obj = data.pointer; |
1214 | |
1215 | return 0; |
1216 | } |
1217 | |
1218 | static void wmi_notify_driver(struct wmi_block *wblock, union acpi_object *obj) |
1219 | { |
1220 | struct wmi_driver *driver = drv_to_wdrv(drv: wblock->dev.dev.driver); |
1221 | |
1222 | if (!obj && !driver->no_notify_data) { |
1223 | dev_warn(&wblock->dev.dev, "Event contains no event data\n" ); |
1224 | return; |
1225 | } |
1226 | |
1227 | if (driver->notify) |
1228 | driver->notify(&wblock->dev, obj); |
1229 | } |
1230 | |
1231 | static int wmi_notify_device(struct device *dev, void *data) |
1232 | { |
1233 | struct wmi_block *wblock = dev_to_wblock(dev); |
1234 | union acpi_object *obj; |
1235 | u32 *event = data; |
1236 | int ret; |
1237 | |
1238 | if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event)) |
1239 | return 0; |
1240 | |
1241 | down_read(sem: &wblock->notify_lock); |
1242 | /* The WMI driver notify handler conflicts with the legacy WMI handler. |
1243 | * Because of this the WMI driver notify handler takes precedence. |
1244 | */ |
1245 | if (wblock->dev.dev.driver && wblock->driver_ready) { |
1246 | ret = wmi_get_notify_data(wblock, obj: &obj); |
1247 | if (ret >= 0) { |
1248 | wmi_notify_driver(wblock, obj); |
1249 | kfree(objp: obj); |
1250 | } |
1251 | } else { |
1252 | if (wblock->handler) { |
1253 | wblock->handler(*event, wblock->handler_data); |
1254 | } else { |
1255 | /* The ACPI WMI specification says that _WED should be |
1256 | * evaluated every time an notification is received, even |
1257 | * if no consumers are present. |
1258 | * |
1259 | * Some firmware implementations actually depend on this |
1260 | * by using a queue for events which will fill up if the |
1261 | * WMI driver core stops evaluating _WED due to missing |
1262 | * WMI event consumers. |
1263 | * |
1264 | * Because of this we need this seemingly useless call to |
1265 | * wmi_get_notify_data() which in turn evaluates _WED. |
1266 | */ |
1267 | ret = wmi_get_notify_data(wblock, obj: &obj); |
1268 | if (ret >= 0) |
1269 | kfree(objp: obj); |
1270 | } |
1271 | |
1272 | } |
1273 | up_read(sem: &wblock->notify_lock); |
1274 | |
1275 | acpi_bus_generate_netlink_event("wmi" , acpi_dev_name(adev: wblock->acpi_device), *event, 0); |
1276 | |
1277 | return -EBUSY; |
1278 | } |
1279 | |
1280 | static void acpi_wmi_notify_handler(acpi_handle handle, u32 event, void *context) |
1281 | { |
1282 | struct device *wmi_bus_dev = context; |
1283 | |
1284 | device_for_each_child(dev: wmi_bus_dev, data: &event, fn: wmi_notify_device); |
1285 | } |
1286 | |
1287 | static int wmi_remove_device(struct device *dev, void *data) |
1288 | { |
1289 | struct wmi_block *wblock = dev_to_wblock(dev); |
1290 | |
1291 | list_del(entry: &wblock->list); |
1292 | device_unregister(dev); |
1293 | |
1294 | return 0; |
1295 | } |
1296 | |
1297 | static void acpi_wmi_remove(struct platform_device *device) |
1298 | { |
1299 | struct device *wmi_bus_device = dev_get_drvdata(dev: &device->dev); |
1300 | |
1301 | device_for_each_child_reverse(dev: wmi_bus_device, NULL, fn: wmi_remove_device); |
1302 | } |
1303 | |
1304 | static void acpi_wmi_remove_notify_handler(void *data) |
1305 | { |
1306 | struct acpi_device *acpi_device = data; |
1307 | |
1308 | acpi_remove_notify_handler(device: acpi_device->handle, ACPI_ALL_NOTIFY, handler: acpi_wmi_notify_handler); |
1309 | } |
1310 | |
1311 | static void acpi_wmi_remove_address_space_handler(void *data) |
1312 | { |
1313 | struct acpi_device *acpi_device = data; |
1314 | |
1315 | acpi_remove_address_space_handler(device: acpi_device->handle, ACPI_ADR_SPACE_EC, |
1316 | handler: &acpi_wmi_ec_space_handler); |
1317 | } |
1318 | |
1319 | static void acpi_wmi_remove_bus_device(void *data) |
1320 | { |
1321 | struct device *wmi_bus_dev = data; |
1322 | |
1323 | device_unregister(dev: wmi_bus_dev); |
1324 | } |
1325 | |
1326 | static int acpi_wmi_probe(struct platform_device *device) |
1327 | { |
1328 | struct acpi_device *acpi_device; |
1329 | struct device *wmi_bus_dev; |
1330 | acpi_status status; |
1331 | int error; |
1332 | |
1333 | acpi_device = ACPI_COMPANION(&device->dev); |
1334 | if (!acpi_device) { |
1335 | dev_err(&device->dev, "ACPI companion is missing\n" ); |
1336 | return -ENODEV; |
1337 | } |
1338 | |
1339 | wmi_bus_dev = device_create(cls: &wmi_bus_class, parent: &device->dev, MKDEV(0, 0), NULL, fmt: "wmi_bus-%s" , |
1340 | dev_name(dev: &device->dev)); |
1341 | if (IS_ERR(ptr: wmi_bus_dev)) |
1342 | return PTR_ERR(ptr: wmi_bus_dev); |
1343 | |
1344 | error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_bus_device, wmi_bus_dev); |
1345 | if (error < 0) |
1346 | return error; |
1347 | |
1348 | dev_set_drvdata(dev: &device->dev, data: wmi_bus_dev); |
1349 | |
1350 | status = acpi_install_address_space_handler(device: acpi_device->handle, |
1351 | ACPI_ADR_SPACE_EC, |
1352 | handler: &acpi_wmi_ec_space_handler, |
1353 | NULL, NULL); |
1354 | if (ACPI_FAILURE(status)) { |
1355 | dev_err(&device->dev, "Error installing EC region handler\n" ); |
1356 | return -ENODEV; |
1357 | } |
1358 | error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_address_space_handler, |
1359 | acpi_device); |
1360 | if (error < 0) |
1361 | return error; |
1362 | |
1363 | status = acpi_install_notify_handler(device: acpi_device->handle, ACPI_ALL_NOTIFY, |
1364 | handler: acpi_wmi_notify_handler, context: wmi_bus_dev); |
1365 | if (ACPI_FAILURE(status)) { |
1366 | dev_err(&device->dev, "Error installing notify handler\n" ); |
1367 | return -ENODEV; |
1368 | } |
1369 | error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_notify_handler, |
1370 | acpi_device); |
1371 | if (error < 0) |
1372 | return error; |
1373 | |
1374 | error = parse_wdg(wmi_bus_dev, pdev: device); |
1375 | if (error) { |
1376 | dev_err(&device->dev, "Failed to parse _WDG method\n" ); |
1377 | return error; |
1378 | } |
1379 | |
1380 | return 0; |
1381 | } |
1382 | |
1383 | int __must_check __wmi_driver_register(struct wmi_driver *driver, |
1384 | struct module *owner) |
1385 | { |
1386 | driver->driver.owner = owner; |
1387 | driver->driver.bus = &wmi_bus_type; |
1388 | |
1389 | return driver_register(drv: &driver->driver); |
1390 | } |
1391 | EXPORT_SYMBOL(__wmi_driver_register); |
1392 | |
1393 | /** |
1394 | * wmi_driver_unregister() - Unregister a WMI driver |
1395 | * @driver: WMI driver to unregister |
1396 | * |
1397 | * Unregisters a WMI driver from the WMI bus. |
1398 | */ |
1399 | void wmi_driver_unregister(struct wmi_driver *driver) |
1400 | { |
1401 | driver_unregister(drv: &driver->driver); |
1402 | } |
1403 | EXPORT_SYMBOL(wmi_driver_unregister); |
1404 | |
1405 | static struct platform_driver acpi_wmi_driver = { |
1406 | .driver = { |
1407 | .name = "acpi-wmi" , |
1408 | .acpi_match_table = wmi_device_ids, |
1409 | }, |
1410 | .probe = acpi_wmi_probe, |
1411 | .remove_new = acpi_wmi_remove, |
1412 | }; |
1413 | |
1414 | static int __init acpi_wmi_init(void) |
1415 | { |
1416 | int error; |
1417 | |
1418 | if (acpi_disabled) |
1419 | return -ENODEV; |
1420 | |
1421 | error = class_register(class: &wmi_bus_class); |
1422 | if (error) |
1423 | return error; |
1424 | |
1425 | error = bus_register(bus: &wmi_bus_type); |
1426 | if (error) |
1427 | goto err_unreg_class; |
1428 | |
1429 | error = platform_driver_register(&acpi_wmi_driver); |
1430 | if (error) { |
1431 | pr_err("Error loading mapper\n" ); |
1432 | goto err_unreg_bus; |
1433 | } |
1434 | |
1435 | return 0; |
1436 | |
1437 | err_unreg_bus: |
1438 | bus_unregister(bus: &wmi_bus_type); |
1439 | |
1440 | err_unreg_class: |
1441 | class_unregister(class: &wmi_bus_class); |
1442 | |
1443 | return error; |
1444 | } |
1445 | |
1446 | static void __exit acpi_wmi_exit(void) |
1447 | { |
1448 | platform_driver_unregister(&acpi_wmi_driver); |
1449 | bus_unregister(bus: &wmi_bus_type); |
1450 | class_unregister(class: &wmi_bus_class); |
1451 | } |
1452 | |
1453 | subsys_initcall_sync(acpi_wmi_init); |
1454 | module_exit(acpi_wmi_exit); |
1455 | |