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v4.6
  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 LIST_HEAD(wmi_block_list);
 49
 50struct 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
 63struct 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
 82static bool debug_event;
 83module_param(debug_event, bool, 0444);
 84MODULE_PARM_DESC(debug_event,
 85		 "Log WMI Events [0/1]");
 86
 87static bool debug_dump_wdg;
 88module_param(debug_dump_wdg, bool, 0444);
 89MODULE_PARM_DESC(debug_dump_wdg,
 90		 "Dump available WMI interfaces [0/1]");
 91
 92static int acpi_wmi_remove(struct acpi_device *device);
 93static int acpi_wmi_add(struct acpi_device *device);
 94static void acpi_wmi_notify(struct acpi_device *device, u32 event);
 95
 96static const struct acpi_device_id wmi_device_ids[] = {
 97	{"PNP0C14", 0},
 98	{"pnp0c14", 0},
 99	{"", 0},
100};
101MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
102
103static 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 */
127static 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 */
151static 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 */
177static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
197static 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
220static 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 */
252acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
253u32 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}
300EXPORT_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 */
310acpi_status wmi_query_block(const char *guid_string, u8 instance,
311struct 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		status = acpi_execute_simple_method(handle, wc_method, 0);
 
 
371	}
372
373	return status;
374}
375EXPORT_SYMBOL_GPL(wmi_query_block);
376
377/**
378 * wmi_set_block - Write to a WMI block
379 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
380 * @instance: Instance index
381 * &in: Buffer containing new values for the data block
382 *
383 * Write the contents of the input buffer to an ACPI-WMI data block
384 */
385acpi_status wmi_set_block(const char *guid_string, u8 instance,
386const struct acpi_buffer *in)
387{
388	struct guid_block *block = NULL;
389	struct wmi_block *wblock = NULL;
390	acpi_handle handle;
391	struct acpi_object_list input;
392	union acpi_object params[2];
393	char method[5] = "WS";
394
395	if (!guid_string || !in)
396		return AE_BAD_DATA;
397
398	if (!find_guid(guid_string, &wblock))
399		return AE_ERROR;
400
401	block = &wblock->gblock;
402	handle = wblock->handle;
403
404	if (block->instance_count < instance)
405		return AE_BAD_PARAMETER;
406
407	/* Check GUID is a data block */
408	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
409		return AE_ERROR;
410
411	input.count = 2;
412	input.pointer = params;
413	params[0].type = ACPI_TYPE_INTEGER;
414	params[0].integer.value = instance;
415
416	if (block->flags & ACPI_WMI_STRING) {
417		params[1].type = ACPI_TYPE_STRING;
418	} else {
419		params[1].type = ACPI_TYPE_BUFFER;
420	}
421	params[1].buffer.length = in->length;
422	params[1].buffer.pointer = in->pointer;
423
424	strncat(method, block->object_id, 2);
425
426	return acpi_evaluate_object(handle, method, &input, NULL);
427}
428EXPORT_SYMBOL_GPL(wmi_set_block);
429
430static void wmi_dump_wdg(const struct guid_block *g)
431{
432	pr_info("%pUL:\n", g->guid);
 
 
 
 
433	pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
434	pr_info("\tnotify_id: %02X\n", g->notify_id);
435	pr_info("\treserved: %02X\n", g->reserved);
436	pr_info("\tinstance_count: %d\n", g->instance_count);
437	pr_info("\tflags: %#x", g->flags);
438	if (g->flags) {
439		if (g->flags & ACPI_WMI_EXPENSIVE)
440			pr_cont(" ACPI_WMI_EXPENSIVE");
441		if (g->flags & ACPI_WMI_METHOD)
442			pr_cont(" ACPI_WMI_METHOD");
443		if (g->flags & ACPI_WMI_STRING)
444			pr_cont(" ACPI_WMI_STRING");
445		if (g->flags & ACPI_WMI_EVENT)
446			pr_cont(" ACPI_WMI_EVENT");
447	}
448	pr_cont("\n");
449
450}
451
452static void wmi_notify_debug(u32 value, void *context)
453{
454	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
455	union acpi_object *obj;
456	acpi_status status;
457
458	status = wmi_get_event_data(value, &response);
459	if (status != AE_OK) {
460		pr_info("bad event status 0x%x\n", status);
461		return;
462	}
463
464	obj = (union acpi_object *)response.pointer;
465
466	if (!obj)
467		return;
468
469	pr_info("DEBUG Event ");
470	switch(obj->type) {
471	case ACPI_TYPE_BUFFER:
472		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
473		break;
474	case ACPI_TYPE_STRING:
475		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
476		break;
477	case ACPI_TYPE_INTEGER:
478		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
479		break;
480	case ACPI_TYPE_PACKAGE:
481		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
482		break;
483	default:
484		pr_cont("object type 0x%X\n", obj->type);
485	}
486	kfree(obj);
487}
488
489/**
490 * wmi_install_notify_handler - Register handler for WMI events
491 * @handler: Function to handle notifications
492 * @data: Data to be returned to handler when event is fired
493 *
494 * Register a handler for events sent to the ACPI-WMI mapper device.
495 */
496acpi_status wmi_install_notify_handler(const char *guid,
497wmi_notify_handler handler, void *data)
498{
499	struct wmi_block *block;
500	acpi_status status = AE_NOT_EXIST;
501	char tmp[16], guid_input[16];
502	struct list_head *p;
503
504	if (!guid || !handler)
505		return AE_BAD_PARAMETER;
506
507	wmi_parse_guid(guid, tmp);
508	wmi_swap_bytes(tmp, guid_input);
509
510	list_for_each(p, &wmi_block_list) {
511		acpi_status wmi_status;
512		block = list_entry(p, struct wmi_block, list);
513
514		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
515			if (block->handler &&
516			    block->handler != wmi_notify_debug)
517				return AE_ALREADY_ACQUIRED;
518
519			block->handler = handler;
520			block->handler_data = data;
521
522			wmi_status = wmi_method_enable(block, 1);
523			if ((wmi_status != AE_OK) ||
524			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
525				status = wmi_status;
526		}
527	}
528
529	return status;
530}
531EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
532
533/**
534 * wmi_uninstall_notify_handler - Unregister handler for WMI events
535 *
536 * Unregister handler for events sent to the ACPI-WMI mapper device.
537 */
538acpi_status wmi_remove_notify_handler(const char *guid)
539{
540	struct wmi_block *block;
541	acpi_status status = AE_NOT_EXIST;
542	char tmp[16], guid_input[16];
543	struct list_head *p;
544
545	if (!guid)
546		return AE_BAD_PARAMETER;
547
548	wmi_parse_guid(guid, tmp);
549	wmi_swap_bytes(tmp, guid_input);
550
551	list_for_each(p, &wmi_block_list) {
552		acpi_status wmi_status;
553		block = list_entry(p, struct wmi_block, list);
554
555		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
556			if (!block->handler ||
557			    block->handler == wmi_notify_debug)
558				return AE_NULL_ENTRY;
559
560			if (debug_event) {
561				block->handler = wmi_notify_debug;
562				status = AE_OK;
563			} else {
564				wmi_status = wmi_method_enable(block, 0);
565				block->handler = NULL;
566				block->handler_data = NULL;
567				if ((wmi_status != AE_OK) ||
568				    ((wmi_status == AE_OK) &&
569				     (status == AE_NOT_EXIST)))
570					status = wmi_status;
571			}
572		}
573	}
574
575	return status;
576}
577EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
578
579/**
580 * wmi_get_event_data - Get WMI data associated with an event
581 *
582 * @event: Event to find
583 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
584 *
585 * Returns extra data associated with an event in WMI.
586 */
587acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
588{
589	struct acpi_object_list input;
590	union acpi_object params[1];
591	struct guid_block *gblock;
592	struct wmi_block *wblock;
593	struct list_head *p;
594
595	input.count = 1;
596	input.pointer = params;
597	params[0].type = ACPI_TYPE_INTEGER;
598	params[0].integer.value = event;
599
600	list_for_each(p, &wmi_block_list) {
601		wblock = list_entry(p, struct wmi_block, list);
602		gblock = &wblock->gblock;
603
604		if ((gblock->flags & ACPI_WMI_EVENT) &&
605			(gblock->notify_id == event))
606			return acpi_evaluate_object(wblock->handle, "_WED",
607				&input, out);
608	}
609
610	return AE_NOT_FOUND;
611}
612EXPORT_SYMBOL_GPL(wmi_get_event_data);
613
614/**
615 * wmi_has_guid - Check if a GUID is available
616 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
617 *
618 * Check if a given GUID is defined by _WDG
619 */
620bool wmi_has_guid(const char *guid_string)
621{
622	return find_guid(guid_string, NULL);
623}
624EXPORT_SYMBOL_GPL(wmi_has_guid);
625
626/*
627 * sysfs interface
628 */
629static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
630			     char *buf)
631{
 
632	struct wmi_block *wblock;
633
634	wblock = dev_get_drvdata(dev);
635	if (!wblock) {
636		strcat(buf, "\n");
637		return strlen(buf);
638	}
639
640	return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
641}
642static DEVICE_ATTR_RO(modalias);
643
644static struct attribute *wmi_attrs[] = {
645	&dev_attr_modalias.attr,
646	NULL,
647};
648ATTRIBUTE_GROUPS(wmi);
649
650static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
651{
652	char guid_string[37];
653
654	struct wmi_block *wblock;
655
656	if (add_uevent_var(env, "MODALIAS="))
657		return -ENOMEM;
658
659	wblock = dev_get_drvdata(dev);
660	if (!wblock)
661		return -ENOMEM;
662
663	sprintf(guid_string, "%pUL", wblock->gblock.guid);
664
665	strcpy(&env->buf[env->buflen - 1], "wmi:");
666	memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
667	env->buflen += 40;
668
669	return 0;
670}
671
672static void wmi_dev_free(struct device *dev)
673{
674	struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
675
676	kfree(wmi_block);
677}
678
679static struct class wmi_class = {
680	.name = "wmi",
681	.dev_release = wmi_dev_free,
682	.dev_uevent = wmi_dev_uevent,
683	.dev_groups = wmi_groups,
684};
685
686static int wmi_create_device(const struct guid_block *gblock,
687			     struct wmi_block *wblock, acpi_handle handle)
688{
 
 
689	wblock->dev.class = &wmi_class;
690
691	dev_set_name(&wblock->dev, "%pUL", gblock->guid);
 
692
693	dev_set_drvdata(&wblock->dev, wblock);
694
695	return device_register(&wblock->dev);
696}
697
698static void wmi_free_devices(void)
699{
700	struct wmi_block *wblock, *next;
701
702	/* Delete devices for all the GUIDs */
703	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
704		list_del(&wblock->list);
705		if (wblock->dev.class)
706			device_unregister(&wblock->dev);
707		else
708			kfree(wblock);
709	}
710}
711
712static bool guid_already_parsed(const char *guid_string)
713{
714	struct wmi_block *wblock;
715
716	list_for_each_entry(wblock, &wmi_block_list, list)
717		if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
718			return true;
719
720	return false;
721}
722
723/*
724 * Parse the _WDG method for the GUID data blocks
725 */
726static int parse_wdg(acpi_handle handle)
727{
728	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
729	union acpi_object *obj;
730	const struct guid_block *gblock;
731	struct wmi_block *wblock;
732	acpi_status status;
733	int retval;
734	u32 i, total;
735
736	status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
737	if (ACPI_FAILURE(status))
738		return -ENXIO;
739
740	obj = (union acpi_object *) out.pointer;
741	if (!obj)
742		return -ENXIO;
743
744	if (obj->type != ACPI_TYPE_BUFFER) {
745		retval = -ENXIO;
746		goto out_free_pointer;
747	}
748
749	gblock = (const struct guid_block *)obj->buffer.pointer;
750	total = obj->buffer.length / sizeof(struct guid_block);
751
752	for (i = 0; i < total; i++) {
753		if (debug_dump_wdg)
754			wmi_dump_wdg(&gblock[i]);
755
756		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
757		if (!wblock)
758			return -ENOMEM;
759
760		wblock->handle = handle;
761		wblock->gblock = gblock[i];
762
763		/*
764		  Some WMI devices, like those for nVidia hooks, have a
765		  duplicate GUID. It's not clear what we should do in this
766		  case yet, so for now, we'll just ignore the duplicate
767		  for device creation.
768		*/
769		if (!guid_already_parsed(gblock[i].guid)) {
770			retval = wmi_create_device(&gblock[i], wblock, handle);
771			if (retval) {
772				wmi_free_devices();
773				goto out_free_pointer;
774			}
775		}
776
777		list_add_tail(&wblock->list, &wmi_block_list);
778
779		if (debug_event) {
780			wblock->handler = wmi_notify_debug;
781			wmi_method_enable(wblock, 1);
782		}
783	}
784
785	retval = 0;
786
787out_free_pointer:
788	kfree(out.pointer);
789
790	return retval;
791}
792
793/*
794 * WMI can have EmbeddedControl access regions. In which case, we just want to
795 * hand these off to the EC driver.
796 */
797static acpi_status
798acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
799		      u32 bits, u64 *value,
800		      void *handler_context, void *region_context)
801{
802	int result = 0, i = 0;
803	u8 temp = 0;
804
805	if ((address > 0xFF) || !value)
806		return AE_BAD_PARAMETER;
807
808	if (function != ACPI_READ && function != ACPI_WRITE)
809		return AE_BAD_PARAMETER;
810
811	if (bits != 8)
812		return AE_BAD_PARAMETER;
813
814	if (function == ACPI_READ) {
815		result = ec_read(address, &temp);
816		(*value) |= ((u64)temp) << i;
817	} else {
818		temp = 0xff & ((*value) >> i);
819		result = ec_write(address, temp);
820	}
821
822	switch (result) {
823	case -EINVAL:
824		return AE_BAD_PARAMETER;
825		break;
826	case -ENODEV:
827		return AE_NOT_FOUND;
828		break;
829	case -ETIME:
830		return AE_TIME;
831		break;
832	default:
833		return AE_OK;
834	}
835}
836
837static void acpi_wmi_notify(struct acpi_device *device, u32 event)
838{
839	struct guid_block *block;
840	struct wmi_block *wblock;
841	struct list_head *p;
 
842
843	list_for_each(p, &wmi_block_list) {
844		wblock = list_entry(p, struct wmi_block, list);
845		block = &wblock->gblock;
846
847		if ((block->flags & ACPI_WMI_EVENT) &&
848			(block->notify_id == event)) {
849			if (wblock->handler)
850				wblock->handler(event, wblock->handler_data);
851			if (debug_event) {
852				pr_info("DEBUG Event GUID: %pUL\n",
853					wblock->gblock.guid);
854			}
855
856			acpi_bus_generate_netlink_event(
857				device->pnp.device_class, dev_name(&device->dev),
858				event, 0);
859			break;
860		}
861	}
862}
863
864static int acpi_wmi_remove(struct acpi_device *device)
865{
866	acpi_remove_address_space_handler(device->handle,
867				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
868	wmi_free_devices();
869
870	return 0;
871}
872
873static int acpi_wmi_add(struct acpi_device *device)
874{
875	acpi_status status;
876	int error;
877
878	status = acpi_install_address_space_handler(device->handle,
879						    ACPI_ADR_SPACE_EC,
880						    &acpi_wmi_ec_space_handler,
881						    NULL, NULL);
882	if (ACPI_FAILURE(status)) {
883		pr_err("Error installing EC region handler\n");
884		return -ENODEV;
885	}
886
887	error = parse_wdg(device->handle);
888	if (error) {
889		acpi_remove_address_space_handler(device->handle,
890						  ACPI_ADR_SPACE_EC,
891						  &acpi_wmi_ec_space_handler);
892		pr_err("Failed to parse WDG method\n");
893		return error;
894	}
895
896	return 0;
897}
898
899static int __init acpi_wmi_init(void)
900{
901	int error;
902
903	if (acpi_disabled)
904		return -ENODEV;
905
906	error = class_register(&wmi_class);
907	if (error)
908		return error;
909
910	error = acpi_bus_register_driver(&acpi_wmi_driver);
911	if (error) {
912		pr_err("Error loading mapper\n");
913		class_unregister(&wmi_class);
914		return error;
915	}
916
917	pr_info("Mapper loaded\n");
918	return 0;
919}
920
921static void __exit acpi_wmi_exit(void)
922{
923	acpi_bus_unregister_driver(&acpi_wmi_driver);
924	class_unregister(&wmi_class);
925
926	pr_info("Mapper unloaded\n");
927}
928
929subsys_initcall(acpi_wmi_init);
930module_exit(acpi_wmi_exit);
v3.1
  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 <acpi/acpi_bus.h>
 40#include <acpi/acpi_drivers.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 DEFINE_MUTEX(wmi_data_lock);
 50static LIST_HEAD(wmi_block_list);
 51
 52struct guid_block {
 53	char guid[16];
 54	union {
 55		char object_id[2];
 56		struct {
 57			unsigned char notify_id;
 58			unsigned char reserved;
 59		};
 60	};
 61	u8 instance_count;
 62	u8 flags;
 63};
 64
 65struct wmi_block {
 66	struct list_head list;
 67	struct guid_block gblock;
 68	acpi_handle handle;
 69	wmi_notify_handler handler;
 70	void *handler_data;
 71	struct device dev;
 72};
 73
 74
 75/*
 76 * If the GUID data block is marked as expensive, we must enable and
 77 * explicitily disable data collection.
 78 */
 79#define ACPI_WMI_EXPENSIVE   0x1
 80#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
 81#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
 82#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
 83
 84static int debug_event;
 85module_param(debug_event, bool, 0444);
 86MODULE_PARM_DESC(debug_event,
 87		 "Log WMI Events [0/1]");
 88
 89static int debug_dump_wdg;
 90module_param(debug_dump_wdg, bool, 0444);
 91MODULE_PARM_DESC(debug_dump_wdg,
 92		 "Dump available WMI interfaces [0/1]");
 93
 94static int acpi_wmi_remove(struct acpi_device *device, int type);
 95static int acpi_wmi_add(struct acpi_device *device);
 96static void acpi_wmi_notify(struct acpi_device *device, u32 event);
 97
 98static const struct acpi_device_id wmi_device_ids[] = {
 99	{"PNP0C14", 0},
100	{"pnp0c14", 0},
101	{"", 0},
102};
103MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
104
105static struct acpi_driver acpi_wmi_driver = {
106	.name = "wmi",
107	.class = ACPI_WMI_CLASS,
108	.ids = wmi_device_ids,
109	.ops = {
110		.add = acpi_wmi_add,
111		.remove = acpi_wmi_remove,
112		.notify = acpi_wmi_notify,
113	},
114};
115
116/*
117 * GUID parsing functions
118 */
119
120/**
121 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
122 * @src:  Pointer to at least 2 characters to convert.
123 *
124 * Convert a two character ASCII hex string to a number.
125 *
126 * Return:  0-255  Success, the byte was parsed correctly
127 *          -1     Error, an invalid character was supplied
128 */
129static int wmi_parse_hexbyte(const u8 *src)
130{
131	int h;
132	int value;
133
134	/* high part */
135	h = value = hex_to_bin(src[0]);
136	if (value < 0)
137		return -1;
138
139	/* low part */
140	value = hex_to_bin(src[1]);
141	if (value >= 0)
142		return (h << 4) | value;
143	return -1;
144}
145
146/**
147 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
148 * @src:   Memory block holding binary GUID (16 bytes)
149 * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
150 *
151 * Byte swap a binary GUID to match it's real GUID value
152 */
153static void wmi_swap_bytes(u8 *src, u8 *dest)
154{
155	int i;
156
157	for (i = 0; i <= 3; i++)
158		memcpy(dest + i, src + (3 - i), 1);
159
160	for (i = 0; i <= 1; i++)
161		memcpy(dest + 4 + i, src + (5 - i), 1);
162
163	for (i = 0; i <= 1; i++)
164		memcpy(dest + 6 + i, src + (7 - i), 1);
165
166	memcpy(dest + 8, src + 8, 8);
167}
168
169/**
170 * wmi_parse_guid - Convert GUID from ASCII to binary
171 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
172 * @dest:  Memory block to hold binary GUID (16 bytes)
173 *
174 * N.B. The GUID need not be NULL terminated.
175 *
176 * Return:  'true'   @dest contains binary GUID
177 *          'false'  @dest contents are undefined
178 */
179static bool wmi_parse_guid(const u8 *src, u8 *dest)
180{
181	static const int size[] = { 4, 2, 2, 2, 6 };
182	int i, j, v;
183
184	if (src[8]  != '-' || src[13] != '-' ||
185		src[18] != '-' || src[23] != '-')
186		return false;
187
188	for (j = 0; j < 5; j++, src++) {
189		for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
190			v = wmi_parse_hexbyte(src);
191			if (v < 0)
192				return false;
193		}
194	}
195
196	return true;
197}
198
199/*
200 * Convert a raw GUID to the ACII string representation
201 */
202static int wmi_gtoa(const char *in, char *out)
203{
204	int i;
205
206	for (i = 3; i >= 0; i--)
207		out += sprintf(out, "%02X", in[i] & 0xFF);
208
209	out += sprintf(out, "-");
210	out += sprintf(out, "%02X", in[5] & 0xFF);
211	out += sprintf(out, "%02X", in[4] & 0xFF);
212	out += sprintf(out, "-");
213	out += sprintf(out, "%02X", in[7] & 0xFF);
214	out += sprintf(out, "%02X", in[6] & 0xFF);
215	out += sprintf(out, "-");
216	out += sprintf(out, "%02X", in[8] & 0xFF);
217	out += sprintf(out, "%02X", in[9] & 0xFF);
218	out += sprintf(out, "-");
219
220	for (i = 10; i <= 15; i++)
221		out += sprintf(out, "%02X", in[i] & 0xFF);
222
223	*out = '\0';
224	return 0;
225}
226
227static bool find_guid(const char *guid_string, struct wmi_block **out)
228{
229	char tmp[16], guid_input[16];
230	struct wmi_block *wblock;
231	struct guid_block *block;
232	struct list_head *p;
233
234	wmi_parse_guid(guid_string, tmp);
235	wmi_swap_bytes(tmp, guid_input);
236
237	list_for_each(p, &wmi_block_list) {
238		wblock = list_entry(p, struct wmi_block, list);
239		block = &wblock->gblock;
240
241		if (memcmp(block->guid, guid_input, 16) == 0) {
242			if (out)
243				*out = wblock;
244			return 1;
245		}
246	}
247	return 0;
248}
249
250static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
251{
252	struct guid_block *block = NULL;
253	char method[5];
254	struct acpi_object_list input;
255	union acpi_object params[1];
256	acpi_status status;
257	acpi_handle handle;
258
259	block = &wblock->gblock;
260	handle = wblock->handle;
261
262	if (!block)
263		return AE_NOT_EXIST;
264
265	input.count = 1;
266	input.pointer = params;
267	params[0].type = ACPI_TYPE_INTEGER;
268	params[0].integer.value = enable;
269
270	snprintf(method, 5, "WE%02X", block->notify_id);
271	status = acpi_evaluate_object(handle, method, &input, NULL);
272
273	if (status != AE_OK && status != AE_NOT_FOUND)
274		return status;
275	else
276		return AE_OK;
277}
278
279/*
280 * Exported WMI functions
281 */
282/**
283 * wmi_evaluate_method - Evaluate a WMI method
284 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
285 * @instance: Instance index
286 * @method_id: Method ID to call
287 * &in: Buffer containing input for the method call
288 * &out: Empty buffer to return the method results
289 *
290 * Call an ACPI-WMI method
291 */
292acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
293u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
294{
295	struct guid_block *block = NULL;
296	struct wmi_block *wblock = NULL;
297	acpi_handle handle;
298	acpi_status status;
299	struct acpi_object_list input;
300	union acpi_object params[3];
301	char method[5] = "WM";
302
303	if (!find_guid(guid_string, &wblock))
304		return AE_ERROR;
305
306	block = &wblock->gblock;
307	handle = wblock->handle;
308
309	if (!(block->flags & ACPI_WMI_METHOD))
310		return AE_BAD_DATA;
311
312	if (block->instance_count < instance)
313		return AE_BAD_PARAMETER;
314
315	input.count = 2;
316	input.pointer = params;
317	params[0].type = ACPI_TYPE_INTEGER;
318	params[0].integer.value = instance;
319	params[1].type = ACPI_TYPE_INTEGER;
320	params[1].integer.value = method_id;
321
322	if (in) {
323		input.count = 3;
324
325		if (block->flags & ACPI_WMI_STRING) {
326			params[2].type = ACPI_TYPE_STRING;
327		} else {
328			params[2].type = ACPI_TYPE_BUFFER;
329		}
330		params[2].buffer.length = in->length;
331		params[2].buffer.pointer = in->pointer;
332	}
333
334	strncat(method, block->object_id, 2);
335
336	status = acpi_evaluate_object(handle, method, &input, out);
337
338	return status;
339}
340EXPORT_SYMBOL_GPL(wmi_evaluate_method);
341
342/**
343 * wmi_query_block - Return contents of a WMI block
344 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
345 * @instance: Instance index
346 * &out: Empty buffer to return the contents of the data block to
347 *
348 * Return the contents of an ACPI-WMI data block to a buffer
349 */
350acpi_status wmi_query_block(const char *guid_string, u8 instance,
351struct acpi_buffer *out)
352{
353	struct guid_block *block = NULL;
354	struct wmi_block *wblock = NULL;
355	acpi_handle handle, wc_handle;
356	acpi_status status, wc_status = AE_ERROR;
357	struct acpi_object_list input, wc_input;
358	union acpi_object wc_params[1], wq_params[1];
359	char method[5];
360	char wc_method[5] = "WC";
361
362	if (!guid_string || !out)
363		return AE_BAD_PARAMETER;
364
365	if (!find_guid(guid_string, &wblock))
366		return AE_ERROR;
367
368	block = &wblock->gblock;
369	handle = wblock->handle;
370
371	if (block->instance_count < instance)
372		return AE_BAD_PARAMETER;
373
374	/* Check GUID is a data block */
375	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
376		return AE_ERROR;
377
378	input.count = 1;
379	input.pointer = wq_params;
380	wq_params[0].type = ACPI_TYPE_INTEGER;
381	wq_params[0].integer.value = instance;
382
383	/*
384	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
385	 * enable collection.
386	 */
387	if (block->flags & ACPI_WMI_EXPENSIVE) {
388		wc_input.count = 1;
389		wc_input.pointer = wc_params;
390		wc_params[0].type = ACPI_TYPE_INTEGER;
391		wc_params[0].integer.value = 1;
392
393		strncat(wc_method, block->object_id, 2);
394
395		/*
396		 * Some GUIDs break the specification by declaring themselves
397		 * expensive, but have no corresponding WCxx method. So we
398		 * should not fail if this happens.
399		 */
400		wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
401		if (ACPI_SUCCESS(wc_status))
402			wc_status = acpi_evaluate_object(handle, wc_method,
403				&wc_input, NULL);
404	}
405
406	strcpy(method, "WQ");
407	strncat(method, block->object_id, 2);
408
409	status = acpi_evaluate_object(handle, method, &input, out);
410
411	/*
412	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
413	 * the WQxx method failed - we should disable collection anyway.
414	 */
415	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
416		wc_params[0].integer.value = 0;
417		status = acpi_evaluate_object(handle,
418		wc_method, &wc_input, NULL);
419	}
420
421	return status;
422}
423EXPORT_SYMBOL_GPL(wmi_query_block);
424
425/**
426 * wmi_set_block - Write to a WMI block
427 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
428 * @instance: Instance index
429 * &in: Buffer containing new values for the data block
430 *
431 * Write the contents of the input buffer to an ACPI-WMI data block
432 */
433acpi_status wmi_set_block(const char *guid_string, u8 instance,
434const struct acpi_buffer *in)
435{
436	struct guid_block *block = NULL;
437	struct wmi_block *wblock = NULL;
438	acpi_handle handle;
439	struct acpi_object_list input;
440	union acpi_object params[2];
441	char method[5] = "WS";
442
443	if (!guid_string || !in)
444		return AE_BAD_DATA;
445
446	if (!find_guid(guid_string, &wblock))
447		return AE_ERROR;
448
449	block = &wblock->gblock;
450	handle = wblock->handle;
451
452	if (block->instance_count < instance)
453		return AE_BAD_PARAMETER;
454
455	/* Check GUID is a data block */
456	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
457		return AE_ERROR;
458
459	input.count = 2;
460	input.pointer = params;
461	params[0].type = ACPI_TYPE_INTEGER;
462	params[0].integer.value = instance;
463
464	if (block->flags & ACPI_WMI_STRING) {
465		params[1].type = ACPI_TYPE_STRING;
466	} else {
467		params[1].type = ACPI_TYPE_BUFFER;
468	}
469	params[1].buffer.length = in->length;
470	params[1].buffer.pointer = in->pointer;
471
472	strncat(method, block->object_id, 2);
473
474	return acpi_evaluate_object(handle, method, &input, NULL);
475}
476EXPORT_SYMBOL_GPL(wmi_set_block);
477
478static void wmi_dump_wdg(const struct guid_block *g)
479{
480	char guid_string[37];
481
482	wmi_gtoa(g->guid, guid_string);
483
484	pr_info("%s:\n", guid_string);
485	pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
486	pr_info("\tnotify_id: %02X\n", g->notify_id);
487	pr_info("\treserved: %02X\n", g->reserved);
488	pr_info("\tinstance_count: %d\n", g->instance_count);
489	pr_info("\tflags: %#x", g->flags);
490	if (g->flags) {
491		if (g->flags & ACPI_WMI_EXPENSIVE)
492			pr_cont(" ACPI_WMI_EXPENSIVE");
493		if (g->flags & ACPI_WMI_METHOD)
494			pr_cont(" ACPI_WMI_METHOD");
495		if (g->flags & ACPI_WMI_STRING)
496			pr_cont(" ACPI_WMI_STRING");
497		if (g->flags & ACPI_WMI_EVENT)
498			pr_cont(" ACPI_WMI_EVENT");
499	}
500	pr_cont("\n");
501
502}
503
504static void wmi_notify_debug(u32 value, void *context)
505{
506	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
507	union acpi_object *obj;
508	acpi_status status;
509
510	status = wmi_get_event_data(value, &response);
511	if (status != AE_OK) {
512		pr_info("bad event status 0x%x\n", status);
513		return;
514	}
515
516	obj = (union acpi_object *)response.pointer;
517
518	if (!obj)
519		return;
520
521	pr_info("DEBUG Event ");
522	switch(obj->type) {
523	case ACPI_TYPE_BUFFER:
524		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
525		break;
526	case ACPI_TYPE_STRING:
527		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
528		break;
529	case ACPI_TYPE_INTEGER:
530		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
531		break;
532	case ACPI_TYPE_PACKAGE:
533		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
534		break;
535	default:
536		pr_cont("object type 0x%X\n", obj->type);
537	}
538	kfree(obj);
539}
540
541/**
542 * wmi_install_notify_handler - Register handler for WMI events
543 * @handler: Function to handle notifications
544 * @data: Data to be returned to handler when event is fired
545 *
546 * Register a handler for events sent to the ACPI-WMI mapper device.
547 */
548acpi_status wmi_install_notify_handler(const char *guid,
549wmi_notify_handler handler, void *data)
550{
551	struct wmi_block *block;
552	acpi_status status = AE_NOT_EXIST;
553	char tmp[16], guid_input[16];
554	struct list_head *p;
555
556	if (!guid || !handler)
557		return AE_BAD_PARAMETER;
558
559	wmi_parse_guid(guid, tmp);
560	wmi_swap_bytes(tmp, guid_input);
561
562	list_for_each(p, &wmi_block_list) {
563		acpi_status wmi_status;
564		block = list_entry(p, struct wmi_block, list);
565
566		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
567			if (block->handler &&
568			    block->handler != wmi_notify_debug)
569				return AE_ALREADY_ACQUIRED;
570
571			block->handler = handler;
572			block->handler_data = data;
573
574			wmi_status = wmi_method_enable(block, 1);
575			if ((wmi_status != AE_OK) ||
576			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
577				status = wmi_status;
578		}
579	}
580
581	return status;
582}
583EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
584
585/**
586 * wmi_uninstall_notify_handler - Unregister handler for WMI events
587 *
588 * Unregister handler for events sent to the ACPI-WMI mapper device.
589 */
590acpi_status wmi_remove_notify_handler(const char *guid)
591{
592	struct wmi_block *block;
593	acpi_status status = AE_NOT_EXIST;
594	char tmp[16], guid_input[16];
595	struct list_head *p;
596
597	if (!guid)
598		return AE_BAD_PARAMETER;
599
600	wmi_parse_guid(guid, tmp);
601	wmi_swap_bytes(tmp, guid_input);
602
603	list_for_each(p, &wmi_block_list) {
604		acpi_status wmi_status;
605		block = list_entry(p, struct wmi_block, list);
606
607		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
608			if (!block->handler ||
609			    block->handler == wmi_notify_debug)
610				return AE_NULL_ENTRY;
611
612			if (debug_event) {
613				block->handler = wmi_notify_debug;
614				status = AE_OK;
615			} else {
616				wmi_status = wmi_method_enable(block, 0);
617				block->handler = NULL;
618				block->handler_data = NULL;
619				if ((wmi_status != AE_OK) ||
620				    ((wmi_status == AE_OK) &&
621				     (status == AE_NOT_EXIST)))
622					status = wmi_status;
623			}
624		}
625	}
626
627	return status;
628}
629EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
630
631/**
632 * wmi_get_event_data - Get WMI data associated with an event
633 *
634 * @event: Event to find
635 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
636 *
637 * Returns extra data associated with an event in WMI.
638 */
639acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
640{
641	struct acpi_object_list input;
642	union acpi_object params[1];
643	struct guid_block *gblock;
644	struct wmi_block *wblock;
645	struct list_head *p;
646
647	input.count = 1;
648	input.pointer = params;
649	params[0].type = ACPI_TYPE_INTEGER;
650	params[0].integer.value = event;
651
652	list_for_each(p, &wmi_block_list) {
653		wblock = list_entry(p, struct wmi_block, list);
654		gblock = &wblock->gblock;
655
656		if ((gblock->flags & ACPI_WMI_EVENT) &&
657			(gblock->notify_id == event))
658			return acpi_evaluate_object(wblock->handle, "_WED",
659				&input, out);
660	}
661
662	return AE_NOT_FOUND;
663}
664EXPORT_SYMBOL_GPL(wmi_get_event_data);
665
666/**
667 * wmi_has_guid - Check if a GUID is available
668 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
669 *
670 * Check if a given GUID is defined by _WDG
671 */
672bool wmi_has_guid(const char *guid_string)
673{
674	return find_guid(guid_string, NULL);
675}
676EXPORT_SYMBOL_GPL(wmi_has_guid);
677
678/*
679 * sysfs interface
680 */
681static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
682			     char *buf)
683{
684	char guid_string[37];
685	struct wmi_block *wblock;
686
687	wblock = dev_get_drvdata(dev);
688	if (!wblock)
689		return -ENOMEM;
690
691	wmi_gtoa(wblock->gblock.guid, guid_string);
692
693	return sprintf(buf, "wmi:%s\n", guid_string);
694}
 
695
696static struct device_attribute wmi_dev_attrs[] = {
697	__ATTR_RO(modalias),
698	__ATTR_NULL
699};
 
700
701static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
702{
703	char guid_string[37];
704
705	struct wmi_block *wblock;
706
707	if (add_uevent_var(env, "MODALIAS="))
708		return -ENOMEM;
709
710	wblock = dev_get_drvdata(dev);
711	if (!wblock)
712		return -ENOMEM;
713
714	wmi_gtoa(wblock->gblock.guid, guid_string);
715
716	strcpy(&env->buf[env->buflen - 1], "wmi:");
717	memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
718	env->buflen += 40;
719
720	return 0;
721}
722
723static void wmi_dev_free(struct device *dev)
724{
725	struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
726
727	kfree(wmi_block);
728}
729
730static struct class wmi_class = {
731	.name = "wmi",
732	.dev_release = wmi_dev_free,
733	.dev_uevent = wmi_dev_uevent,
734	.dev_attrs = wmi_dev_attrs,
735};
736
737static int wmi_create_device(const struct guid_block *gblock,
738			     struct wmi_block *wblock, acpi_handle handle)
739{
740	char guid_string[37];
741
742	wblock->dev.class = &wmi_class;
743
744	wmi_gtoa(gblock->guid, guid_string);
745	dev_set_name(&wblock->dev, guid_string);
746
747	dev_set_drvdata(&wblock->dev, wblock);
748
749	return device_register(&wblock->dev);
750}
751
752static void wmi_free_devices(void)
753{
754	struct wmi_block *wblock, *next;
755
756	/* Delete devices for all the GUIDs */
757	list_for_each_entry_safe(wblock, next, &wmi_block_list, list)
 
758		if (wblock->dev.class)
759			device_unregister(&wblock->dev);
 
 
 
760}
761
762static bool guid_already_parsed(const char *guid_string)
763{
764	struct wmi_block *wblock;
765
766	list_for_each_entry(wblock, &wmi_block_list, list)
767		if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
768			return true;
769
770	return false;
771}
772
773/*
774 * Parse the _WDG method for the GUID data blocks
775 */
776static acpi_status parse_wdg(acpi_handle handle)
777{
778	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
779	union acpi_object *obj;
780	const struct guid_block *gblock;
781	struct wmi_block *wblock;
782	acpi_status status;
783	int retval;
784	u32 i, total;
785
786	status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
787	if (ACPI_FAILURE(status))
788		return -ENXIO;
789
790	obj = (union acpi_object *) out.pointer;
791	if (!obj)
792		return -ENXIO;
793
794	if (obj->type != ACPI_TYPE_BUFFER) {
795		retval = -ENXIO;
796		goto out_free_pointer;
797	}
798
799	gblock = (const struct guid_block *)obj->buffer.pointer;
800	total = obj->buffer.length / sizeof(struct guid_block);
801
802	for (i = 0; i < total; i++) {
803		if (debug_dump_wdg)
804			wmi_dump_wdg(&gblock[i]);
805
806		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
807		if (!wblock)
808			return AE_NO_MEMORY;
809
810		wblock->handle = handle;
811		wblock->gblock = gblock[i];
812
813		/*
814		  Some WMI devices, like those for nVidia hooks, have a
815		  duplicate GUID. It's not clear what we should do in this
816		  case yet, so for now, we'll just ignore the duplicate
817		  for device creation.
818		*/
819		if (!guid_already_parsed(gblock[i].guid)) {
820			retval = wmi_create_device(&gblock[i], wblock, handle);
821			if (retval) {
822				wmi_free_devices();
823				goto out_free_pointer;
824			}
825		}
826
827		list_add_tail(&wblock->list, &wmi_block_list);
828
829		if (debug_event) {
830			wblock->handler = wmi_notify_debug;
831			wmi_method_enable(wblock, 1);
832		}
833	}
834
835	retval = 0;
836
837out_free_pointer:
838	kfree(out.pointer);
839
840	return retval;
841}
842
843/*
844 * WMI can have EmbeddedControl access regions. In which case, we just want to
845 * hand these off to the EC driver.
846 */
847static acpi_status
848acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
849		      u32 bits, u64 *value,
850		      void *handler_context, void *region_context)
851{
852	int result = 0, i = 0;
853	u8 temp = 0;
854
855	if ((address > 0xFF) || !value)
856		return AE_BAD_PARAMETER;
857
858	if (function != ACPI_READ && function != ACPI_WRITE)
859		return AE_BAD_PARAMETER;
860
861	if (bits != 8)
862		return AE_BAD_PARAMETER;
863
864	if (function == ACPI_READ) {
865		result = ec_read(address, &temp);
866		(*value) |= ((u64)temp) << i;
867	} else {
868		temp = 0xff & ((*value) >> i);
869		result = ec_write(address, temp);
870	}
871
872	switch (result) {
873	case -EINVAL:
874		return AE_BAD_PARAMETER;
875		break;
876	case -ENODEV:
877		return AE_NOT_FOUND;
878		break;
879	case -ETIME:
880		return AE_TIME;
881		break;
882	default:
883		return AE_OK;
884	}
885}
886
887static void acpi_wmi_notify(struct acpi_device *device, u32 event)
888{
889	struct guid_block *block;
890	struct wmi_block *wblock;
891	struct list_head *p;
892	char guid_string[37];
893
894	list_for_each(p, &wmi_block_list) {
895		wblock = list_entry(p, struct wmi_block, list);
896		block = &wblock->gblock;
897
898		if ((block->flags & ACPI_WMI_EVENT) &&
899			(block->notify_id == event)) {
900			if (wblock->handler)
901				wblock->handler(event, wblock->handler_data);
902			if (debug_event) {
903				wmi_gtoa(wblock->gblock.guid, guid_string);
904				pr_info("DEBUG Event GUID: %s\n", guid_string);
905			}
906
907			acpi_bus_generate_netlink_event(
908				device->pnp.device_class, dev_name(&device->dev),
909				event, 0);
910			break;
911		}
912	}
913}
914
915static int acpi_wmi_remove(struct acpi_device *device, int type)
916{
917	acpi_remove_address_space_handler(device->handle,
918				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
919	wmi_free_devices();
920
921	return 0;
922}
923
924static int acpi_wmi_add(struct acpi_device *device)
925{
926	acpi_status status;
927	int error;
928
929	status = acpi_install_address_space_handler(device->handle,
930						    ACPI_ADR_SPACE_EC,
931						    &acpi_wmi_ec_space_handler,
932						    NULL, NULL);
933	if (ACPI_FAILURE(status)) {
934		pr_err("Error installing EC region handler\n");
935		return -ENODEV;
936	}
937
938	error = parse_wdg(device->handle);
939	if (error) {
940		acpi_remove_address_space_handler(device->handle,
941						  ACPI_ADR_SPACE_EC,
942						  &acpi_wmi_ec_space_handler);
943		pr_err("Failed to parse WDG method\n");
944		return error;
945	}
946
947	return 0;
948}
949
950static int __init acpi_wmi_init(void)
951{
952	int error;
953
954	if (acpi_disabled)
955		return -ENODEV;
956
957	error = class_register(&wmi_class);
958	if (error)
959		return error;
960
961	error = acpi_bus_register_driver(&acpi_wmi_driver);
962	if (error) {
963		pr_err("Error loading mapper\n");
964		class_unregister(&wmi_class);
965		return error;
966	}
967
968	pr_info("Mapper loaded\n");
969	return 0;
970}
971
972static void __exit acpi_wmi_exit(void)
973{
974	acpi_bus_unregister_driver(&acpi_wmi_driver);
975	class_unregister(&wmi_class);
976
977	pr_info("Mapper unloaded\n");
978}
979
980subsys_initcall(acpi_wmi_init);
981module_exit(acpi_wmi_exit);