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 #include <acpi/acpi_bus.h>
41 #include <acpi/acpi_drivers.h>
42
43 ACPI_MODULE_NAME("wmi");
44 MODULE_AUTHOR("Carlos Corbacho");
45 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
46 MODULE_LICENSE("GPL");
47
48 #define ACPI_WMI_CLASS "wmi"
49
50 static DEFINE_MUTEX(wmi_data_lock);
51 static LIST_HEAD(wmi_block_list);
52
53 struct guid_block {
54 char guid[16];
55 union {
56 char object_id[2];
57 struct {
58 unsigned char notify_id;
59 unsigned char reserved;
60 };
61 };
62 u8 instance_count;
63 u8 flags;
64 };
65
66 struct wmi_block {
67 struct list_head list;
68 struct guid_block gblock;
69 acpi_handle handle;
70 wmi_notify_handler handler;
71 void *handler_data;
72 struct device dev;
73 };
74
75
76 /*
77 * If the GUID data block is marked as expensive, we must enable and
78 * explicitily disable data collection.
79 */
80 #define ACPI_WMI_EXPENSIVE 0x1
81 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
82 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
83 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
84
85 static bool debug_event;
86 module_param(debug_event, bool, 0444);
87 MODULE_PARM_DESC(debug_event,
88 "Log WMI Events [0/1]");
89
90 static bool debug_dump_wdg;
91 module_param(debug_dump_wdg, bool, 0444);
92 MODULE_PARM_DESC(debug_dump_wdg,
93 "Dump available WMI interfaces [0/1]");
94
95 static int acpi_wmi_remove(struct acpi_device *device, int type);
96 static int acpi_wmi_add(struct acpi_device *device);
97 static void acpi_wmi_notify(struct acpi_device *device, u32 event);
98
99 static const struct acpi_device_id wmi_device_ids[] = {
100 {"PNP0C14", 0},
101 {"pnp0c14", 0},
102 {"", 0},
103 };
104 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
105
106 static struct acpi_driver acpi_wmi_driver = {
107 .name = "wmi",
108 .class = ACPI_WMI_CLASS,
109 .ids = wmi_device_ids,
110 .ops = {
111 .add = acpi_wmi_add,
112 .remove = acpi_wmi_remove,
113 .notify = acpi_wmi_notify,
114 },
115 };
116
117 /*
118 * GUID parsing functions
119 */
120
121 /**
122 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
123 * @src: Pointer to at least 2 characters to convert.
124 *
125 * Convert a two character ASCII hex string to a number.
126 *
127 * Return: 0-255 Success, the byte was parsed correctly
128 * -1 Error, an invalid character was supplied
129 */
wmi_parse_hexbyte(const u8 * src)130 static int wmi_parse_hexbyte(const u8 *src)
131 {
132 int h;
133 int value;
134
135 /* high part */
136 h = value = hex_to_bin(src[0]);
137 if (value < 0)
138 return -1;
139
140 /* low part */
141 value = hex_to_bin(src[1]);
142 if (value >= 0)
143 return (h << 4) | value;
144 return -1;
145 }
146
147 /**
148 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
149 * @src: Memory block holding binary GUID (16 bytes)
150 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
151 *
152 * Byte swap a binary GUID to match it's real GUID value
153 */
wmi_swap_bytes(u8 * src,u8 * dest)154 static void wmi_swap_bytes(u8 *src, u8 *dest)
155 {
156 int i;
157
158 for (i = 0; i <= 3; i++)
159 memcpy(dest + i, src + (3 - i), 1);
160
161 for (i = 0; i <= 1; i++)
162 memcpy(dest + 4 + i, src + (5 - i), 1);
163
164 for (i = 0; i <= 1; i++)
165 memcpy(dest + 6 + i, src + (7 - i), 1);
166
167 memcpy(dest + 8, src + 8, 8);
168 }
169
170 /**
171 * wmi_parse_guid - Convert GUID from ASCII to binary
172 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
173 * @dest: Memory block to hold binary GUID (16 bytes)
174 *
175 * N.B. The GUID need not be NULL terminated.
176 *
177 * Return: 'true' @dest contains binary GUID
178 * 'false' @dest contents are undefined
179 */
wmi_parse_guid(const u8 * src,u8 * dest)180 static bool wmi_parse_guid(const u8 *src, u8 *dest)
181 {
182 static const int size[] = { 4, 2, 2, 2, 6 };
183 int i, j, v;
184
185 if (src[8] != '-' || src[13] != '-' ||
186 src[18] != '-' || src[23] != '-')
187 return false;
188
189 for (j = 0; j < 5; j++, src++) {
190 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
191 v = wmi_parse_hexbyte(src);
192 if (v < 0)
193 return false;
194 }
195 }
196
197 return true;
198 }
199
200 /*
201 * Convert a raw GUID to the ACII string representation
202 */
wmi_gtoa(const char * in,char * out)203 static int wmi_gtoa(const char *in, char *out)
204 {
205 int i;
206
207 for (i = 3; i >= 0; i--)
208 out += sprintf(out, "%02X", in[i] & 0xFF);
209
210 out += sprintf(out, "-");
211 out += sprintf(out, "%02X", in[5] & 0xFF);
212 out += sprintf(out, "%02X", in[4] & 0xFF);
213 out += sprintf(out, "-");
214 out += sprintf(out, "%02X", in[7] & 0xFF);
215 out += sprintf(out, "%02X", in[6] & 0xFF);
216 out += sprintf(out, "-");
217 out += sprintf(out, "%02X", in[8] & 0xFF);
218 out += sprintf(out, "%02X", in[9] & 0xFF);
219 out += sprintf(out, "-");
220
221 for (i = 10; i <= 15; i++)
222 out += sprintf(out, "%02X", in[i] & 0xFF);
223
224 *out = '\0';
225 return 0;
226 }
227
find_guid(const char * guid_string,struct wmi_block ** out)228 static bool find_guid(const char *guid_string, struct wmi_block **out)
229 {
230 char tmp[16], guid_input[16];
231 struct wmi_block *wblock;
232 struct guid_block *block;
233 struct list_head *p;
234
235 wmi_parse_guid(guid_string, tmp);
236 wmi_swap_bytes(tmp, guid_input);
237
238 list_for_each(p, &wmi_block_list) {
239 wblock = list_entry(p, struct wmi_block, list);
240 block = &wblock->gblock;
241
242 if (memcmp(block->guid, guid_input, 16) == 0) {
243 if (out)
244 *out = wblock;
245 return 1;
246 }
247 }
248 return 0;
249 }
250
wmi_method_enable(struct wmi_block * wblock,int enable)251 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
252 {
253 struct guid_block *block = NULL;
254 char method[5];
255 struct acpi_object_list input;
256 union acpi_object params[1];
257 acpi_status status;
258 acpi_handle handle;
259
260 block = &wblock->gblock;
261 handle = wblock->handle;
262
263 if (!block)
264 return AE_NOT_EXIST;
265
266 input.count = 1;
267 input.pointer = params;
268 params[0].type = ACPI_TYPE_INTEGER;
269 params[0].integer.value = enable;
270
271 snprintf(method, 5, "WE%02X", block->notify_id);
272 status = acpi_evaluate_object(handle, method, &input, NULL);
273
274 if (status != AE_OK && status != AE_NOT_FOUND)
275 return status;
276 else
277 return AE_OK;
278 }
279
280 /*
281 * Exported WMI functions
282 */
283 /**
284 * wmi_evaluate_method - Evaluate a WMI method
285 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
286 * @instance: Instance index
287 * @method_id: Method ID to call
288 * &in: Buffer containing input for the method call
289 * &out: Empty buffer to return the method results
290 *
291 * Call an ACPI-WMI method
292 */
wmi_evaluate_method(const char * guid_string,u8 instance,u32 method_id,const struct acpi_buffer * in,struct acpi_buffer * out)293 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
294 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
295 {
296 struct guid_block *block = NULL;
297 struct wmi_block *wblock = NULL;
298 acpi_handle handle;
299 acpi_status status;
300 struct acpi_object_list input;
301 union acpi_object params[3];
302 char method[5] = "WM";
303
304 if (!find_guid(guid_string, &wblock))
305 return AE_ERROR;
306
307 block = &wblock->gblock;
308 handle = wblock->handle;
309
310 if (!(block->flags & ACPI_WMI_METHOD))
311 return AE_BAD_DATA;
312
313 if (block->instance_count < instance)
314 return AE_BAD_PARAMETER;
315
316 input.count = 2;
317 input.pointer = params;
318 params[0].type = ACPI_TYPE_INTEGER;
319 params[0].integer.value = instance;
320 params[1].type = ACPI_TYPE_INTEGER;
321 params[1].integer.value = method_id;
322
323 if (in) {
324 input.count = 3;
325
326 if (block->flags & ACPI_WMI_STRING) {
327 params[2].type = ACPI_TYPE_STRING;
328 } else {
329 params[2].type = ACPI_TYPE_BUFFER;
330 }
331 params[2].buffer.length = in->length;
332 params[2].buffer.pointer = in->pointer;
333 }
334
335 strncat(method, block->object_id, 2);
336
337 status = acpi_evaluate_object(handle, method, &input, out);
338
339 return status;
340 }
341 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
342
343 /**
344 * wmi_query_block - Return contents of a WMI block
345 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
346 * @instance: Instance index
347 * &out: Empty buffer to return the contents of the data block to
348 *
349 * Return the contents of an ACPI-WMI data block to a buffer
350 */
wmi_query_block(const char * guid_string,u8 instance,struct acpi_buffer * out)351 acpi_status wmi_query_block(const char *guid_string, u8 instance,
352 struct acpi_buffer *out)
353 {
354 struct guid_block *block = NULL;
355 struct wmi_block *wblock = NULL;
356 acpi_handle handle, wc_handle;
357 acpi_status status, wc_status = AE_ERROR;
358 struct acpi_object_list input, wc_input;
359 union acpi_object wc_params[1], wq_params[1];
360 char method[5];
361 char wc_method[5] = "WC";
362
363 if (!guid_string || !out)
364 return AE_BAD_PARAMETER;
365
366 if (!find_guid(guid_string, &wblock))
367 return AE_ERROR;
368
369 block = &wblock->gblock;
370 handle = wblock->handle;
371
372 if (block->instance_count < instance)
373 return AE_BAD_PARAMETER;
374
375 /* Check GUID is a data block */
376 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
377 return AE_ERROR;
378
379 input.count = 1;
380 input.pointer = wq_params;
381 wq_params[0].type = ACPI_TYPE_INTEGER;
382 wq_params[0].integer.value = instance;
383
384 /*
385 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
386 * enable collection.
387 */
388 if (block->flags & ACPI_WMI_EXPENSIVE) {
389 wc_input.count = 1;
390 wc_input.pointer = wc_params;
391 wc_params[0].type = ACPI_TYPE_INTEGER;
392 wc_params[0].integer.value = 1;
393
394 strncat(wc_method, block->object_id, 2);
395
396 /*
397 * Some GUIDs break the specification by declaring themselves
398 * expensive, but have no corresponding WCxx method. So we
399 * should not fail if this happens.
400 */
401 wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
402 if (ACPI_SUCCESS(wc_status))
403 wc_status = acpi_evaluate_object(handle, wc_method,
404 &wc_input, NULL);
405 }
406
407 strcpy(method, "WQ");
408 strncat(method, block->object_id, 2);
409
410 status = acpi_evaluate_object(handle, method, &input, out);
411
412 /*
413 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
414 * the WQxx method failed - we should disable collection anyway.
415 */
416 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
417 wc_params[0].integer.value = 0;
418 status = acpi_evaluate_object(handle,
419 wc_method, &wc_input, NULL);
420 }
421
422 return status;
423 }
424 EXPORT_SYMBOL_GPL(wmi_query_block);
425
426 /**
427 * wmi_set_block - Write to a WMI block
428 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
429 * @instance: Instance index
430 * &in: Buffer containing new values for the data block
431 *
432 * Write the contents of the input buffer to an ACPI-WMI data block
433 */
wmi_set_block(const char * guid_string,u8 instance,const struct acpi_buffer * in)434 acpi_status wmi_set_block(const char *guid_string, u8 instance,
435 const struct acpi_buffer *in)
436 {
437 struct guid_block *block = NULL;
438 struct wmi_block *wblock = NULL;
439 acpi_handle handle;
440 struct acpi_object_list input;
441 union acpi_object params[2];
442 char method[5] = "WS";
443
444 if (!guid_string || !in)
445 return AE_BAD_DATA;
446
447 if (!find_guid(guid_string, &wblock))
448 return AE_ERROR;
449
450 block = &wblock->gblock;
451 handle = wblock->handle;
452
453 if (block->instance_count < instance)
454 return AE_BAD_PARAMETER;
455
456 /* Check GUID is a data block */
457 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
458 return AE_ERROR;
459
460 input.count = 2;
461 input.pointer = params;
462 params[0].type = ACPI_TYPE_INTEGER;
463 params[0].integer.value = instance;
464
465 if (block->flags & ACPI_WMI_STRING) {
466 params[1].type = ACPI_TYPE_STRING;
467 } else {
468 params[1].type = ACPI_TYPE_BUFFER;
469 }
470 params[1].buffer.length = in->length;
471 params[1].buffer.pointer = in->pointer;
472
473 strncat(method, block->object_id, 2);
474
475 return acpi_evaluate_object(handle, method, &input, NULL);
476 }
477 EXPORT_SYMBOL_GPL(wmi_set_block);
478
wmi_dump_wdg(const struct guid_block * g)479 static void wmi_dump_wdg(const struct guid_block *g)
480 {
481 char guid_string[37];
482
483 wmi_gtoa(g->guid, guid_string);
484
485 pr_info("%s:\n", guid_string);
486 pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
487 pr_info("\tnotify_id: %02X\n", g->notify_id);
488 pr_info("\treserved: %02X\n", g->reserved);
489 pr_info("\tinstance_count: %d\n", g->instance_count);
490 pr_info("\tflags: %#x", g->flags);
491 if (g->flags) {
492 if (g->flags & ACPI_WMI_EXPENSIVE)
493 pr_cont(" ACPI_WMI_EXPENSIVE");
494 if (g->flags & ACPI_WMI_METHOD)
495 pr_cont(" ACPI_WMI_METHOD");
496 if (g->flags & ACPI_WMI_STRING)
497 pr_cont(" ACPI_WMI_STRING");
498 if (g->flags & ACPI_WMI_EVENT)
499 pr_cont(" ACPI_WMI_EVENT");
500 }
501 pr_cont("\n");
502
503 }
504
wmi_notify_debug(u32 value,void * context)505 static void wmi_notify_debug(u32 value, void *context)
506 {
507 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
508 union acpi_object *obj;
509 acpi_status status;
510
511 status = wmi_get_event_data(value, &response);
512 if (status != AE_OK) {
513 pr_info("bad event status 0x%x\n", status);
514 return;
515 }
516
517 obj = (union acpi_object *)response.pointer;
518
519 if (!obj)
520 return;
521
522 pr_info("DEBUG Event ");
523 switch(obj->type) {
524 case ACPI_TYPE_BUFFER:
525 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
526 break;
527 case ACPI_TYPE_STRING:
528 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
529 break;
530 case ACPI_TYPE_INTEGER:
531 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
532 break;
533 case ACPI_TYPE_PACKAGE:
534 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
535 break;
536 default:
537 pr_cont("object type 0x%X\n", obj->type);
538 }
539 kfree(obj);
540 }
541
542 /**
543 * wmi_install_notify_handler - Register handler for WMI events
544 * @handler: Function to handle notifications
545 * @data: Data to be returned to handler when event is fired
546 *
547 * Register a handler for events sent to the ACPI-WMI mapper device.
548 */
wmi_install_notify_handler(const char * guid,wmi_notify_handler handler,void * data)549 acpi_status wmi_install_notify_handler(const char *guid,
550 wmi_notify_handler handler, void *data)
551 {
552 struct wmi_block *block;
553 acpi_status status = AE_NOT_EXIST;
554 char tmp[16], guid_input[16];
555 struct list_head *p;
556
557 if (!guid || !handler)
558 return AE_BAD_PARAMETER;
559
560 wmi_parse_guid(guid, tmp);
561 wmi_swap_bytes(tmp, guid_input);
562
563 list_for_each(p, &wmi_block_list) {
564 acpi_status wmi_status;
565 block = list_entry(p, struct wmi_block, list);
566
567 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
568 if (block->handler &&
569 block->handler != wmi_notify_debug)
570 return AE_ALREADY_ACQUIRED;
571
572 block->handler = handler;
573 block->handler_data = data;
574
575 wmi_status = wmi_method_enable(block, 1);
576 if ((wmi_status != AE_OK) ||
577 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
578 status = wmi_status;
579 }
580 }
581
582 return status;
583 }
584 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
585
586 /**
587 * wmi_uninstall_notify_handler - Unregister handler for WMI events
588 *
589 * Unregister handler for events sent to the ACPI-WMI mapper device.
590 */
wmi_remove_notify_handler(const char * guid)591 acpi_status wmi_remove_notify_handler(const char *guid)
592 {
593 struct wmi_block *block;
594 acpi_status status = AE_NOT_EXIST;
595 char tmp[16], guid_input[16];
596 struct list_head *p;
597
598 if (!guid)
599 return AE_BAD_PARAMETER;
600
601 wmi_parse_guid(guid, tmp);
602 wmi_swap_bytes(tmp, guid_input);
603
604 list_for_each(p, &wmi_block_list) {
605 acpi_status wmi_status;
606 block = list_entry(p, struct wmi_block, list);
607
608 if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
609 if (!block->handler ||
610 block->handler == wmi_notify_debug)
611 return AE_NULL_ENTRY;
612
613 if (debug_event) {
614 block->handler = wmi_notify_debug;
615 status = AE_OK;
616 } else {
617 wmi_status = wmi_method_enable(block, 0);
618 block->handler = NULL;
619 block->handler_data = NULL;
620 if ((wmi_status != AE_OK) ||
621 ((wmi_status == AE_OK) &&
622 (status == AE_NOT_EXIST)))
623 status = wmi_status;
624 }
625 }
626 }
627
628 return status;
629 }
630 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
631
632 /**
633 * wmi_get_event_data - Get WMI data associated with an event
634 *
635 * @event: Event to find
636 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
637 *
638 * Returns extra data associated with an event in WMI.
639 */
wmi_get_event_data(u32 event,struct acpi_buffer * out)640 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
641 {
642 struct acpi_object_list input;
643 union acpi_object params[1];
644 struct guid_block *gblock;
645 struct wmi_block *wblock;
646 struct list_head *p;
647
648 input.count = 1;
649 input.pointer = params;
650 params[0].type = ACPI_TYPE_INTEGER;
651 params[0].integer.value = event;
652
653 list_for_each(p, &wmi_block_list) {
654 wblock = list_entry(p, struct wmi_block, list);
655 gblock = &wblock->gblock;
656
657 if ((gblock->flags & ACPI_WMI_EVENT) &&
658 (gblock->notify_id == event))
659 return acpi_evaluate_object(wblock->handle, "_WED",
660 &input, out);
661 }
662
663 return AE_NOT_FOUND;
664 }
665 EXPORT_SYMBOL_GPL(wmi_get_event_data);
666
667 /**
668 * wmi_has_guid - Check if a GUID is available
669 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
670 *
671 * Check if a given GUID is defined by _WDG
672 */
wmi_has_guid(const char * guid_string)673 bool wmi_has_guid(const char *guid_string)
674 {
675 return find_guid(guid_string, NULL);
676 }
677 EXPORT_SYMBOL_GPL(wmi_has_guid);
678
679 /*
680 * sysfs interface
681 */
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)682 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
683 char *buf)
684 {
685 char guid_string[37];
686 struct wmi_block *wblock;
687
688 wblock = dev_get_drvdata(dev);
689 if (!wblock)
690 return -ENOMEM;
691
692 wmi_gtoa(wblock->gblock.guid, guid_string);
693
694 return sprintf(buf, "wmi:%s\n", guid_string);
695 }
696
697 static struct device_attribute wmi_dev_attrs[] = {
698 __ATTR_RO(modalias),
699 __ATTR_NULL
700 };
701
wmi_dev_uevent(struct device * dev,struct kobj_uevent_env * env)702 static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
703 {
704 char guid_string[37];
705
706 struct wmi_block *wblock;
707
708 if (add_uevent_var(env, "MODALIAS="))
709 return -ENOMEM;
710
711 wblock = dev_get_drvdata(dev);
712 if (!wblock)
713 return -ENOMEM;
714
715 wmi_gtoa(wblock->gblock.guid, guid_string);
716
717 strcpy(&env->buf[env->buflen - 1], "wmi:");
718 memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
719 env->buflen += 40;
720
721 return 0;
722 }
723
wmi_dev_free(struct device * dev)724 static void wmi_dev_free(struct device *dev)
725 {
726 struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
727
728 kfree(wmi_block);
729 }
730
731 static struct class wmi_class = {
732 .name = "wmi",
733 .dev_release = wmi_dev_free,
734 .dev_uevent = wmi_dev_uevent,
735 .dev_attrs = wmi_dev_attrs,
736 };
737
wmi_create_device(const struct guid_block * gblock,struct wmi_block * wblock,acpi_handle handle)738 static int wmi_create_device(const struct guid_block *gblock,
739 struct wmi_block *wblock, acpi_handle handle)
740 {
741 char guid_string[37];
742
743 wblock->dev.class = &wmi_class;
744
745 wmi_gtoa(gblock->guid, guid_string);
746 dev_set_name(&wblock->dev, guid_string);
747
748 dev_set_drvdata(&wblock->dev, wblock);
749
750 return device_register(&wblock->dev);
751 }
752
wmi_free_devices(void)753 static void wmi_free_devices(void)
754 {
755 struct wmi_block *wblock, *next;
756
757 /* Delete devices for all the GUIDs */
758 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
759 list_del(&wblock->list);
760 if (wblock->dev.class)
761 device_unregister(&wblock->dev);
762 else
763 kfree(wblock);
764 }
765 }
766
guid_already_parsed(const char * guid_string)767 static bool guid_already_parsed(const char *guid_string)
768 {
769 struct wmi_block *wblock;
770
771 list_for_each_entry(wblock, &wmi_block_list, list)
772 if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
773 return true;
774
775 return false;
776 }
777
778 /*
779 * Parse the _WDG method for the GUID data blocks
780 */
parse_wdg(acpi_handle handle)781 static acpi_status parse_wdg(acpi_handle handle)
782 {
783 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
784 union acpi_object *obj;
785 const struct guid_block *gblock;
786 struct wmi_block *wblock;
787 acpi_status status;
788 int retval;
789 u32 i, total;
790
791 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
792 if (ACPI_FAILURE(status))
793 return -ENXIO;
794
795 obj = (union acpi_object *) out.pointer;
796 if (!obj)
797 return -ENXIO;
798
799 if (obj->type != ACPI_TYPE_BUFFER) {
800 retval = -ENXIO;
801 goto out_free_pointer;
802 }
803
804 gblock = (const struct guid_block *)obj->buffer.pointer;
805 total = obj->buffer.length / sizeof(struct guid_block);
806
807 for (i = 0; i < total; i++) {
808 if (debug_dump_wdg)
809 wmi_dump_wdg(&gblock[i]);
810
811 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
812 if (!wblock)
813 return AE_NO_MEMORY;
814
815 wblock->handle = handle;
816 wblock->gblock = gblock[i];
817
818 /*
819 Some WMI devices, like those for nVidia hooks, have a
820 duplicate GUID. It's not clear what we should do in this
821 case yet, so for now, we'll just ignore the duplicate
822 for device creation.
823 */
824 if (!guid_already_parsed(gblock[i].guid)) {
825 retval = wmi_create_device(&gblock[i], wblock, handle);
826 if (retval) {
827 wmi_free_devices();
828 goto out_free_pointer;
829 }
830 }
831
832 list_add_tail(&wblock->list, &wmi_block_list);
833
834 if (debug_event) {
835 wblock->handler = wmi_notify_debug;
836 wmi_method_enable(wblock, 1);
837 }
838 }
839
840 retval = 0;
841
842 out_free_pointer:
843 kfree(out.pointer);
844
845 return retval;
846 }
847
848 /*
849 * WMI can have EmbeddedControl access regions. In which case, we just want to
850 * hand these off to the EC driver.
851 */
852 static acpi_status
acpi_wmi_ec_space_handler(u32 function,acpi_physical_address address,u32 bits,u64 * value,void * handler_context,void * region_context)853 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
854 u32 bits, u64 *value,
855 void *handler_context, void *region_context)
856 {
857 int result = 0, i = 0;
858 u8 temp = 0;
859
860 if ((address > 0xFF) || !value)
861 return AE_BAD_PARAMETER;
862
863 if (function != ACPI_READ && function != ACPI_WRITE)
864 return AE_BAD_PARAMETER;
865
866 if (bits != 8)
867 return AE_BAD_PARAMETER;
868
869 if (function == ACPI_READ) {
870 result = ec_read(address, &temp);
871 (*value) |= ((u64)temp) << i;
872 } else {
873 temp = 0xff & ((*value) >> i);
874 result = ec_write(address, temp);
875 }
876
877 switch (result) {
878 case -EINVAL:
879 return AE_BAD_PARAMETER;
880 break;
881 case -ENODEV:
882 return AE_NOT_FOUND;
883 break;
884 case -ETIME:
885 return AE_TIME;
886 break;
887 default:
888 return AE_OK;
889 }
890 }
891
acpi_wmi_notify(struct acpi_device * device,u32 event)892 static void acpi_wmi_notify(struct acpi_device *device, u32 event)
893 {
894 struct guid_block *block;
895 struct wmi_block *wblock;
896 struct list_head *p;
897 char guid_string[37];
898
899 list_for_each(p, &wmi_block_list) {
900 wblock = list_entry(p, struct wmi_block, list);
901 block = &wblock->gblock;
902
903 if ((block->flags & ACPI_WMI_EVENT) &&
904 (block->notify_id == event)) {
905 if (wblock->handler)
906 wblock->handler(event, wblock->handler_data);
907 if (debug_event) {
908 wmi_gtoa(wblock->gblock.guid, guid_string);
909 pr_info("DEBUG Event GUID: %s\n", guid_string);
910 }
911
912 acpi_bus_generate_netlink_event(
913 device->pnp.device_class, dev_name(&device->dev),
914 event, 0);
915 break;
916 }
917 }
918 }
919
acpi_wmi_remove(struct acpi_device * device,int type)920 static int acpi_wmi_remove(struct acpi_device *device, int type)
921 {
922 acpi_remove_address_space_handler(device->handle,
923 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
924 wmi_free_devices();
925
926 return 0;
927 }
928
acpi_wmi_add(struct acpi_device * device)929 static int acpi_wmi_add(struct acpi_device *device)
930 {
931 acpi_status status;
932 int error;
933
934 status = acpi_install_address_space_handler(device->handle,
935 ACPI_ADR_SPACE_EC,
936 &acpi_wmi_ec_space_handler,
937 NULL, NULL);
938 if (ACPI_FAILURE(status)) {
939 pr_err("Error installing EC region handler\n");
940 return -ENODEV;
941 }
942
943 error = parse_wdg(device->handle);
944 if (error) {
945 acpi_remove_address_space_handler(device->handle,
946 ACPI_ADR_SPACE_EC,
947 &acpi_wmi_ec_space_handler);
948 pr_err("Failed to parse WDG method\n");
949 return error;
950 }
951
952 return 0;
953 }
954
acpi_wmi_init(void)955 static int __init acpi_wmi_init(void)
956 {
957 int error;
958
959 if (acpi_disabled)
960 return -ENODEV;
961
962 error = class_register(&wmi_class);
963 if (error)
964 return error;
965
966 error = acpi_bus_register_driver(&acpi_wmi_driver);
967 if (error) {
968 pr_err("Error loading mapper\n");
969 class_unregister(&wmi_class);
970 return error;
971 }
972
973 pr_info("Mapper loaded\n");
974 return 0;
975 }
976
acpi_wmi_exit(void)977 static void __exit acpi_wmi_exit(void)
978 {
979 acpi_bus_unregister_driver(&acpi_wmi_driver);
980 class_unregister(&wmi_class);
981
982 pr_info("Mapper unloaded\n");
983 }
984
985 subsys_initcall(acpi_wmi_init);
986 module_exit(acpi_wmi_exit);
987