1 /*
2 * ACPI-WMI mapping driver
3 *
4 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
5 *
6 * GUID parsing code from ldm.c is:
7 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
8 * Copyright (c) 2001-2007 Anton Altaparmakov
9 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
10 *
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 *
27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 */
29
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
32 #include <linux/kernel.h>
33 #include <linux/init.h>
34 #include <linux/types.h>
35 #include <linux/device.h>
36 #include <linux/list.h>
37 #include <linux/acpi.h>
38 #include <linux/slab.h>
39 #include <linux/module.h>
40
41 ACPI_MODULE_NAME("wmi");
42 MODULE_AUTHOR("Carlos Corbacho");
43 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
44 MODULE_LICENSE("GPL");
45
46 #define ACPI_WMI_CLASS "wmi"
47
48 static LIST_HEAD(wmi_block_list);
49
50 struct guid_block {
51 char guid[16];
52 union {
53 char object_id[2];
54 struct {
55 unsigned char notify_id;
56 unsigned char reserved;
57 };
58 };
59 u8 instance_count;
60 u8 flags;
61 };
62
63 struct wmi_block {
64 struct list_head list;
65 struct guid_block gblock;
66 acpi_handle handle;
67 wmi_notify_handler handler;
68 void *handler_data;
69 struct device dev;
70 };
71
72
73 /*
74 * If the GUID data block is marked as expensive, we must enable and
75 * explicitily disable data collection.
76 */
77 #define ACPI_WMI_EXPENSIVE 0x1
78 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
79 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
80 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
81
82 static bool debug_event;
83 module_param(debug_event, bool, 0444);
84 MODULE_PARM_DESC(debug_event,
85 "Log WMI Events [0/1]");
86
87 static bool debug_dump_wdg;
88 module_param(debug_dump_wdg, bool, 0444);
89 MODULE_PARM_DESC(debug_dump_wdg,
90 "Dump available WMI interfaces [0/1]");
91
92 static int acpi_wmi_remove(struct acpi_device *device);
93 static int acpi_wmi_add(struct acpi_device *device);
94 static void acpi_wmi_notify(struct acpi_device *device, u32 event);
95
96 static const struct acpi_device_id wmi_device_ids[] = {
97 {"PNP0C14", 0},
98 {"pnp0c14", 0},
99 {"", 0},
100 };
101 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
102
103 static struct acpi_driver acpi_wmi_driver = {
104 .name = "wmi",
105 .class = ACPI_WMI_CLASS,
106 .ids = wmi_device_ids,
107 .ops = {
108 .add = acpi_wmi_add,
109 .remove = acpi_wmi_remove,
110 .notify = acpi_wmi_notify,
111 },
112 };
113
114 /*
115 * GUID parsing functions
116 */
117
118 /**
119 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
120 * @src: Pointer to at least 2 characters to convert.
121 *
122 * Convert a two character ASCII hex string to a number.
123 *
124 * Return: 0-255 Success, the byte was parsed correctly
125 * -1 Error, an invalid character was supplied
126 */
wmi_parse_hexbyte(const u8 * src)127 static int wmi_parse_hexbyte(const u8 *src)
128 {
129 int h;
130 int value;
131
132 /* high part */
133 h = value = hex_to_bin(src[0]);
134 if (value < 0)
135 return -1;
136
137 /* low part */
138 value = hex_to_bin(src[1]);
139 if (value >= 0)
140 return (h << 4) | value;
141 return -1;
142 }
143
144 /**
145 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
146 * @src: Memory block holding binary GUID (16 bytes)
147 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
148 *
149 * Byte swap a binary GUID to match it's real GUID value
150 */
wmi_swap_bytes(u8 * src,u8 * dest)151 static void wmi_swap_bytes(u8 *src, u8 *dest)
152 {
153 int i;
154
155 for (i = 0; i <= 3; i++)
156 memcpy(dest + i, src + (3 - i), 1);
157
158 for (i = 0; i <= 1; i++)
159 memcpy(dest + 4 + i, src + (5 - i), 1);
160
161 for (i = 0; i <= 1; i++)
162 memcpy(dest + 6 + i, src + (7 - i), 1);
163
164 memcpy(dest + 8, src + 8, 8);
165 }
166
167 /**
168 * wmi_parse_guid - Convert GUID from ASCII to binary
169 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
170 * @dest: Memory block to hold binary GUID (16 bytes)
171 *
172 * N.B. The GUID need not be NULL terminated.
173 *
174 * Return: 'true' @dest contains binary GUID
175 * 'false' @dest contents are undefined
176 */
wmi_parse_guid(const u8 * src,u8 * dest)177 static bool wmi_parse_guid(const u8 *src, u8 *dest)
178 {
179 static const int size[] = { 4, 2, 2, 2, 6 };
180 int i, j, v;
181
182 if (src[8] != '-' || src[13] != '-' ||
183 src[18] != '-' || src[23] != '-')
184 return false;
185
186 for (j = 0; j < 5; j++, src++) {
187 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
188 v = wmi_parse_hexbyte(src);
189 if (v < 0)
190 return false;
191 }
192 }
193
194 return true;
195 }
196
find_guid(const char * guid_string,struct wmi_block ** out)197 static bool find_guid(const char *guid_string, struct wmi_block **out)
198 {
199 char tmp[16], guid_input[16];
200 struct wmi_block *wblock;
201 struct guid_block *block;
202 struct list_head *p;
203
204 wmi_parse_guid(guid_string, tmp);
205 wmi_swap_bytes(tmp, guid_input);
206
207 list_for_each(p, &wmi_block_list) {
208 wblock = list_entry(p, struct wmi_block, list);
209 block = &wblock->gblock;
210
211 if (memcmp(block->guid, guid_input, 16) == 0) {
212 if (out)
213 *out = wblock;
214 return true;
215 }
216 }
217 return false;
218 }
219
wmi_method_enable(struct wmi_block * wblock,int enable)220 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
221 {
222 struct guid_block *block = NULL;
223 char method[5];
224 acpi_status status;
225 acpi_handle handle;
226
227 block = &wblock->gblock;
228 handle = wblock->handle;
229
230 snprintf(method, 5, "WE%02X", block->notify_id);
231 status = acpi_execute_simple_method(handle, method, enable);
232
233 if (status != AE_OK && status != AE_NOT_FOUND)
234 return status;
235 else
236 return AE_OK;
237 }
238
239 /*
240 * Exported WMI functions
241 */
242 /**
243 * wmi_evaluate_method - Evaluate a WMI method
244 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
245 * @instance: Instance index
246 * @method_id: Method ID to call
247 * &in: Buffer containing input for the method call
248 * &out: Empty buffer to return the method results
249 *
250 * Call an ACPI-WMI method
251 */
wmi_evaluate_method(const char * guid_string,u8 instance,u32 method_id,const struct acpi_buffer * in,struct acpi_buffer * out)252 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
253 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
254 {
255 struct guid_block *block = NULL;
256 struct wmi_block *wblock = NULL;
257 acpi_handle handle;
258 acpi_status status;
259 struct acpi_object_list input;
260 union acpi_object params[3];
261 char method[5] = "WM";
262
263 if (!find_guid(guid_string, &wblock))
264 return AE_ERROR;
265
266 block = &wblock->gblock;
267 handle = wblock->handle;
268
269 if (!(block->flags & ACPI_WMI_METHOD))
270 return AE_BAD_DATA;
271
272 if (block->instance_count < instance)
273 return AE_BAD_PARAMETER;
274
275 input.count = 2;
276 input.pointer = params;
277 params[0].type = ACPI_TYPE_INTEGER;
278 params[0].integer.value = instance;
279 params[1].type = ACPI_TYPE_INTEGER;
280 params[1].integer.value = method_id;
281
282 if (in) {
283 input.count = 3;
284
285 if (block->flags & ACPI_WMI_STRING) {
286 params[2].type = ACPI_TYPE_STRING;
287 } else {
288 params[2].type = ACPI_TYPE_BUFFER;
289 }
290 params[2].buffer.length = in->length;
291 params[2].buffer.pointer = in->pointer;
292 }
293
294 strncat(method, block->object_id, 2);
295
296 status = acpi_evaluate_object(handle, method, &input, out);
297
298 return status;
299 }
300 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
301
302 /**
303 * wmi_query_block - Return contents of a WMI block
304 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
305 * @instance: Instance index
306 * &out: Empty buffer to return the contents of the data block to
307 *
308 * Return the contents of an ACPI-WMI data block to a buffer
309 */
wmi_query_block(const char * guid_string,u8 instance,struct acpi_buffer * out)310 acpi_status wmi_query_block(const char *guid_string, u8 instance,
311 struct acpi_buffer *out)
312 {
313 struct guid_block *block = NULL;
314 struct wmi_block *wblock = NULL;
315 acpi_handle handle;
316 acpi_status status, wc_status = AE_ERROR;
317 struct acpi_object_list input;
318 union acpi_object wq_params[1];
319 char method[5];
320 char wc_method[5] = "WC";
321
322 if (!guid_string || !out)
323 return AE_BAD_PARAMETER;
324
325 if (!find_guid(guid_string, &wblock))
326 return AE_ERROR;
327
328 block = &wblock->gblock;
329 handle = wblock->handle;
330
331 if (block->instance_count < instance)
332 return AE_BAD_PARAMETER;
333
334 /* Check GUID is a data block */
335 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
336 return AE_ERROR;
337
338 input.count = 1;
339 input.pointer = wq_params;
340 wq_params[0].type = ACPI_TYPE_INTEGER;
341 wq_params[0].integer.value = instance;
342
343 /*
344 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
345 * enable collection.
346 */
347 if (block->flags & ACPI_WMI_EXPENSIVE) {
348 strncat(wc_method, block->object_id, 2);
349
350 /*
351 * Some GUIDs break the specification by declaring themselves
352 * expensive, but have no corresponding WCxx method. So we
353 * should not fail if this happens.
354 */
355 if (acpi_has_method(handle, wc_method))
356 wc_status = acpi_execute_simple_method(handle,
357 wc_method, 1);
358 }
359
360 strcpy(method, "WQ");
361 strncat(method, block->object_id, 2);
362
363 status = acpi_evaluate_object(handle, method, &input, out);
364
365 /*
366 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
367 * the WQxx method failed - we should disable collection anyway.
368 */
369 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
370 /*
371 * Ignore whether this WCxx call succeeds or not since
372 * the previously executed WQxx method call might have
373 * succeeded, and returning the failing status code
374 * of this call would throw away the result of the WQxx
375 * call, potentially leaking memory.
376 */
377 acpi_execute_simple_method(handle, wc_method, 0);
378 }
379
380 return status;
381 }
382 EXPORT_SYMBOL_GPL(wmi_query_block);
383
384 /**
385 * wmi_set_block - Write to a WMI block
386 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
387 * @instance: Instance index
388 * &in: Buffer containing new values for the data block
389 *
390 * Write the contents of the input buffer to an ACPI-WMI data block
391 */
wmi_set_block(const char * guid_string,u8 instance,const struct acpi_buffer * in)392 acpi_status wmi_set_block(const char *guid_string, u8 instance,
393 const struct acpi_buffer *in)
394 {
395 struct guid_block *block = NULL;
396 struct wmi_block *wblock = NULL;
397 acpi_handle handle;
398 struct acpi_object_list input;
399 union acpi_object params[2];
400 char method[5] = "WS";
401
402 if (!guid_string || !in)
403 return AE_BAD_DATA;
404
405 if (!find_guid(guid_string, &wblock))
406 return AE_ERROR;
407
408 block = &wblock->gblock;
409 handle = wblock->handle;
410
411 if (block->instance_count < instance)
412 return AE_BAD_PARAMETER;
413
414 /* Check GUID is a data block */
415 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
416 return AE_ERROR;
417
418 input.count = 2;
419 input.pointer = params;
420 params[0].type = ACPI_TYPE_INTEGER;
421 params[0].integer.value = instance;
422
423 if (block->flags & ACPI_WMI_STRING) {
424 params[1].type = ACPI_TYPE_STRING;
425 } else {
426 params[1].type = ACPI_TYPE_BUFFER;
427 }
428 params[1].buffer.length = in->length;
429 params[1].buffer.pointer = in->pointer;
430
431 strncat(method, block->object_id, 2);
432
433 return acpi_evaluate_object(handle, method, &input, NULL);
434 }
435 EXPORT_SYMBOL_GPL(wmi_set_block);
436
wmi_dump_wdg(const struct guid_block * g)437 static void wmi_dump_wdg(const struct guid_block *g)
438 {
439 pr_info("%pUL:\n", g->guid);
440 pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
441 pr_info("\tnotify_id: %02X\n", g->notify_id);
442 pr_info("\treserved: %02X\n", g->reserved);
443 pr_info("\tinstance_count: %d\n", g->instance_count);
444 pr_info("\tflags: %#x", g->flags);
445 if (g->flags) {
446 if (g->flags & ACPI_WMI_EXPENSIVE)
447 pr_cont(" ACPI_WMI_EXPENSIVE");
448 if (g->flags & ACPI_WMI_METHOD)
449 pr_cont(" ACPI_WMI_METHOD");
450 if (g->flags & ACPI_WMI_STRING)
451 pr_cont(" ACPI_WMI_STRING");
452 if (g->flags & ACPI_WMI_EVENT)
453 pr_cont(" ACPI_WMI_EVENT");
454 }
455 pr_cont("\n");
456
457 }
458
wmi_notify_debug(u32 value,void * context)459 static void wmi_notify_debug(u32 value, void *context)
460 {
461 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
462 union acpi_object *obj;
463 acpi_status status;
464
465 status = wmi_get_event_data(value, &response);
466 if (status != AE_OK) {
467 pr_info("bad event status 0x%x\n", status);
468 return;
469 }
470
471 obj = (union acpi_object *)response.pointer;
472
473 if (!obj)
474 return;
475
476 pr_info("DEBUG Event ");
477 switch(obj->type) {
478 case ACPI_TYPE_BUFFER:
479 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
480 break;
481 case ACPI_TYPE_STRING:
482 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
483 break;
484 case ACPI_TYPE_INTEGER:
485 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
486 break;
487 case ACPI_TYPE_PACKAGE:
488 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
489 break;
490 default:
491 pr_cont("object type 0x%X\n", obj->type);
492 }
493 kfree(obj);
494 }
495
496 /**
497 * wmi_install_notify_handler - Register handler for WMI events
498 * @handler: Function to handle notifications
499 * @data: Data to be returned to handler when event is fired
500 *
501 * Register a handler for events sent to the ACPI-WMI mapper device.
502 */
wmi_install_notify_handler(const char * guid,wmi_notify_handler handler,void * data)503 acpi_status wmi_install_notify_handler(const char *guid,
504 wmi_notify_handler handler, void *data)
505 {
506 struct wmi_block *block;
507 acpi_status status = AE_NOT_EXIST;
508 char tmp[16], guid_input[16];
509 struct list_head *p;
510
511 if (!guid || !handler)
512 return AE_BAD_PARAMETER;
513
514 wmi_parse_guid(guid, tmp);
515 wmi_swap_bytes(tmp, guid_input);
516
517 list_for_each(p, &wmi_block_list) {
518 acpi_status wmi_status;
519 block = list_entry(p, struct wmi_block, list);
520
521 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
522 if (block->handler &&
523 block->handler != wmi_notify_debug)
524 return AE_ALREADY_ACQUIRED;
525
526 block->handler = handler;
527 block->handler_data = data;
528
529 wmi_status = wmi_method_enable(block, 1);
530 if ((wmi_status != AE_OK) ||
531 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
532 status = wmi_status;
533 }
534 }
535
536 return status;
537 }
538 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
539
540 /**
541 * wmi_uninstall_notify_handler - Unregister handler for WMI events
542 *
543 * Unregister handler for events sent to the ACPI-WMI mapper device.
544 */
wmi_remove_notify_handler(const char * guid)545 acpi_status wmi_remove_notify_handler(const char *guid)
546 {
547 struct wmi_block *block;
548 acpi_status status = AE_NOT_EXIST;
549 char tmp[16], guid_input[16];
550 struct list_head *p;
551
552 if (!guid)
553 return AE_BAD_PARAMETER;
554
555 wmi_parse_guid(guid, tmp);
556 wmi_swap_bytes(tmp, guid_input);
557
558 list_for_each(p, &wmi_block_list) {
559 acpi_status wmi_status;
560 block = list_entry(p, struct wmi_block, list);
561
562 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
563 if (!block->handler ||
564 block->handler == wmi_notify_debug)
565 return AE_NULL_ENTRY;
566
567 if (debug_event) {
568 block->handler = wmi_notify_debug;
569 status = AE_OK;
570 } else {
571 wmi_status = wmi_method_enable(block, 0);
572 block->handler = NULL;
573 block->handler_data = NULL;
574 if ((wmi_status != AE_OK) ||
575 ((wmi_status == AE_OK) &&
576 (status == AE_NOT_EXIST)))
577 status = wmi_status;
578 }
579 }
580 }
581
582 return status;
583 }
584 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
585
586 /**
587 * wmi_get_event_data - Get WMI data associated with an event
588 *
589 * @event: Event to find
590 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
591 *
592 * Returns extra data associated with an event in WMI.
593 */
wmi_get_event_data(u32 event,struct acpi_buffer * out)594 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
595 {
596 struct acpi_object_list input;
597 union acpi_object params[1];
598 struct guid_block *gblock;
599 struct wmi_block *wblock;
600 struct list_head *p;
601
602 input.count = 1;
603 input.pointer = params;
604 params[0].type = ACPI_TYPE_INTEGER;
605 params[0].integer.value = event;
606
607 list_for_each(p, &wmi_block_list) {
608 wblock = list_entry(p, struct wmi_block, list);
609 gblock = &wblock->gblock;
610
611 if ((gblock->flags & ACPI_WMI_EVENT) &&
612 (gblock->notify_id == event))
613 return acpi_evaluate_object(wblock->handle, "_WED",
614 &input, out);
615 }
616
617 return AE_NOT_FOUND;
618 }
619 EXPORT_SYMBOL_GPL(wmi_get_event_data);
620
621 /**
622 * wmi_has_guid - Check if a GUID is available
623 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
624 *
625 * Check if a given GUID is defined by _WDG
626 */
wmi_has_guid(const char * guid_string)627 bool wmi_has_guid(const char *guid_string)
628 {
629 return find_guid(guid_string, NULL);
630 }
631 EXPORT_SYMBOL_GPL(wmi_has_guid);
632
633 /*
634 * sysfs interface
635 */
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)636 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
637 char *buf)
638 {
639 struct wmi_block *wblock;
640
641 wblock = dev_get_drvdata(dev);
642 if (!wblock) {
643 strcat(buf, "\n");
644 return strlen(buf);
645 }
646
647 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
648 }
649 static DEVICE_ATTR_RO(modalias);
650
651 static struct attribute *wmi_attrs[] = {
652 &dev_attr_modalias.attr,
653 NULL,
654 };
655 ATTRIBUTE_GROUPS(wmi);
656
wmi_dev_uevent(struct device * dev,struct kobj_uevent_env * env)657 static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
658 {
659 char guid_string[37];
660
661 struct wmi_block *wblock;
662
663 if (add_uevent_var(env, "MODALIAS="))
664 return -ENOMEM;
665
666 wblock = dev_get_drvdata(dev);
667 if (!wblock)
668 return -ENOMEM;
669
670 sprintf(guid_string, "%pUL", wblock->gblock.guid);
671
672 strcpy(&env->buf[env->buflen - 1], "wmi:");
673 memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
674 env->buflen += 40;
675
676 return 0;
677 }
678
wmi_dev_free(struct device * dev)679 static void wmi_dev_free(struct device *dev)
680 {
681 struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
682
683 kfree(wmi_block);
684 }
685
686 static struct class wmi_class = {
687 .name = "wmi",
688 .dev_release = wmi_dev_free,
689 .dev_uevent = wmi_dev_uevent,
690 .dev_groups = wmi_groups,
691 };
692
wmi_create_device(const struct guid_block * gblock,struct wmi_block * wblock,acpi_handle handle)693 static int wmi_create_device(const struct guid_block *gblock,
694 struct wmi_block *wblock, acpi_handle handle)
695 {
696 wblock->dev.class = &wmi_class;
697
698 dev_set_name(&wblock->dev, "%pUL", gblock->guid);
699
700 dev_set_drvdata(&wblock->dev, wblock);
701
702 return device_register(&wblock->dev);
703 }
704
wmi_free_devices(void)705 static void wmi_free_devices(void)
706 {
707 struct wmi_block *wblock, *next;
708
709 /* Delete devices for all the GUIDs */
710 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
711 list_del(&wblock->list);
712 if (wblock->dev.class)
713 device_unregister(&wblock->dev);
714 else
715 kfree(wblock);
716 }
717 }
718
guid_already_parsed(const char * guid_string)719 static bool guid_already_parsed(const char *guid_string)
720 {
721 struct wmi_block *wblock;
722
723 list_for_each_entry(wblock, &wmi_block_list, list)
724 if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
725 return true;
726
727 return false;
728 }
729
730 /*
731 * Parse the _WDG method for the GUID data blocks
732 */
parse_wdg(acpi_handle handle)733 static int parse_wdg(acpi_handle handle)
734 {
735 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
736 union acpi_object *obj;
737 const struct guid_block *gblock;
738 struct wmi_block *wblock;
739 acpi_status status;
740 int retval;
741 u32 i, total;
742
743 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
744 if (ACPI_FAILURE(status))
745 return -ENXIO;
746
747 obj = (union acpi_object *) out.pointer;
748 if (!obj)
749 return -ENXIO;
750
751 if (obj->type != ACPI_TYPE_BUFFER) {
752 retval = -ENXIO;
753 goto out_free_pointer;
754 }
755
756 gblock = (const struct guid_block *)obj->buffer.pointer;
757 total = obj->buffer.length / sizeof(struct guid_block);
758
759 for (i = 0; i < total; i++) {
760 if (debug_dump_wdg)
761 wmi_dump_wdg(&gblock[i]);
762
763 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
764 if (!wblock)
765 return -ENOMEM;
766
767 wblock->handle = handle;
768 wblock->gblock = gblock[i];
769
770 /*
771 Some WMI devices, like those for nVidia hooks, have a
772 duplicate GUID. It's not clear what we should do in this
773 case yet, so for now, we'll just ignore the duplicate
774 for device creation.
775 */
776 if (!guid_already_parsed(gblock[i].guid)) {
777 retval = wmi_create_device(&gblock[i], wblock, handle);
778 if (retval) {
779 wmi_free_devices();
780 goto out_free_pointer;
781 }
782 }
783
784 list_add_tail(&wblock->list, &wmi_block_list);
785
786 if (debug_event) {
787 wblock->handler = wmi_notify_debug;
788 wmi_method_enable(wblock, 1);
789 }
790 }
791
792 retval = 0;
793
794 out_free_pointer:
795 kfree(out.pointer);
796
797 return retval;
798 }
799
800 /*
801 * WMI can have EmbeddedControl access regions. In which case, we just want to
802 * hand these off to the EC driver.
803 */
804 static acpi_status
acpi_wmi_ec_space_handler(u32 function,acpi_physical_address address,u32 bits,u64 * value,void * handler_context,void * region_context)805 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
806 u32 bits, u64 *value,
807 void *handler_context, void *region_context)
808 {
809 int result = 0, i = 0;
810 u8 temp = 0;
811
812 if ((address > 0xFF) || !value)
813 return AE_BAD_PARAMETER;
814
815 if (function != ACPI_READ && function != ACPI_WRITE)
816 return AE_BAD_PARAMETER;
817
818 if (bits != 8)
819 return AE_BAD_PARAMETER;
820
821 if (function == ACPI_READ) {
822 result = ec_read(address, &temp);
823 (*value) |= ((u64)temp) << i;
824 } else {
825 temp = 0xff & ((*value) >> i);
826 result = ec_write(address, temp);
827 }
828
829 switch (result) {
830 case -EINVAL:
831 return AE_BAD_PARAMETER;
832 break;
833 case -ENODEV:
834 return AE_NOT_FOUND;
835 break;
836 case -ETIME:
837 return AE_TIME;
838 break;
839 default:
840 return AE_OK;
841 }
842 }
843
acpi_wmi_notify(struct acpi_device * device,u32 event)844 static void acpi_wmi_notify(struct acpi_device *device, u32 event)
845 {
846 struct guid_block *block;
847 struct wmi_block *wblock;
848 struct list_head *p;
849
850 list_for_each(p, &wmi_block_list) {
851 wblock = list_entry(p, struct wmi_block, list);
852 block = &wblock->gblock;
853
854 if ((block->flags & ACPI_WMI_EVENT) &&
855 (block->notify_id == event)) {
856 if (wblock->handler)
857 wblock->handler(event, wblock->handler_data);
858 if (debug_event) {
859 pr_info("DEBUG Event GUID: %pUL\n",
860 wblock->gblock.guid);
861 }
862
863 acpi_bus_generate_netlink_event(
864 device->pnp.device_class, dev_name(&device->dev),
865 event, 0);
866 break;
867 }
868 }
869 }
870
acpi_wmi_remove(struct acpi_device * device)871 static int acpi_wmi_remove(struct acpi_device *device)
872 {
873 acpi_remove_address_space_handler(device->handle,
874 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
875 wmi_free_devices();
876
877 return 0;
878 }
879
acpi_wmi_add(struct acpi_device * device)880 static int acpi_wmi_add(struct acpi_device *device)
881 {
882 acpi_status status;
883 int error;
884
885 status = acpi_install_address_space_handler(device->handle,
886 ACPI_ADR_SPACE_EC,
887 &acpi_wmi_ec_space_handler,
888 NULL, NULL);
889 if (ACPI_FAILURE(status)) {
890 pr_err("Error installing EC region handler\n");
891 return -ENODEV;
892 }
893
894 error = parse_wdg(device->handle);
895 if (error) {
896 acpi_remove_address_space_handler(device->handle,
897 ACPI_ADR_SPACE_EC,
898 &acpi_wmi_ec_space_handler);
899 pr_err("Failed to parse WDG method\n");
900 return error;
901 }
902
903 return 0;
904 }
905
acpi_wmi_init(void)906 static int __init acpi_wmi_init(void)
907 {
908 int error;
909
910 if (acpi_disabled)
911 return -ENODEV;
912
913 error = class_register(&wmi_class);
914 if (error)
915 return error;
916
917 error = acpi_bus_register_driver(&acpi_wmi_driver);
918 if (error) {
919 pr_err("Error loading mapper\n");
920 class_unregister(&wmi_class);
921 return error;
922 }
923
924 pr_info("Mapper loaded\n");
925 return 0;
926 }
927
acpi_wmi_exit(void)928 static void __exit acpi_wmi_exit(void)
929 {
930 acpi_bus_unregister_driver(&acpi_wmi_driver);
931 class_unregister(&wmi_class);
932
933 pr_info("Mapper unloaded\n");
934 }
935
936 subsys_initcall(acpi_wmi_init);
937 module_exit(acpi_wmi_exit);
938