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