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v3.5.6
  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#include <acpi/acpi_bus.h>
 41#include <acpi/acpi_drivers.h>
 42
 43ACPI_MODULE_NAME("wmi");
 44MODULE_AUTHOR("Carlos Corbacho");
 45MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
 46MODULE_LICENSE("GPL");
 47
 48#define ACPI_WMI_CLASS "wmi"
 49
 50static DEFINE_MUTEX(wmi_data_lock);
 51static LIST_HEAD(wmi_block_list);
 52
 53struct guid_block {
 54	char guid[16];
 55	union {
 56		char object_id[2];
 57		struct {
 58			unsigned char notify_id;
 59			unsigned char reserved;
 60		};
 61	};
 62	u8 instance_count;
 63	u8 flags;
 64};
 65
 66struct wmi_block {
 67	struct list_head list;
 68	struct guid_block gblock;
 69	acpi_handle handle;
 70	wmi_notify_handler handler;
 71	void *handler_data;
 72	struct device dev;
 73};
 74
 75
 76/*
 77 * If the GUID data block is marked as expensive, we must enable and
 78 * explicitily disable data collection.
 79 */
 80#define ACPI_WMI_EXPENSIVE   0x1
 81#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
 82#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
 83#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
 84
 85static bool debug_event;
 86module_param(debug_event, bool, 0444);
 87MODULE_PARM_DESC(debug_event,
 88		 "Log WMI Events [0/1]");
 89
 90static bool debug_dump_wdg;
 91module_param(debug_dump_wdg, bool, 0444);
 92MODULE_PARM_DESC(debug_dump_wdg,
 93		 "Dump available WMI interfaces [0/1]");
 94
 95static int acpi_wmi_remove(struct acpi_device *device, int type);
 96static int acpi_wmi_add(struct acpi_device *device);
 97static void acpi_wmi_notify(struct acpi_device *device, u32 event);
 98
 99static const struct acpi_device_id wmi_device_ids[] = {
100	{"PNP0C14", 0},
101	{"pnp0c14", 0},
102	{"", 0},
103};
104MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
105
106static struct acpi_driver acpi_wmi_driver = {
107	.name = "wmi",
108	.class = ACPI_WMI_CLASS,
109	.ids = wmi_device_ids,
110	.ops = {
111		.add = acpi_wmi_add,
112		.remove = acpi_wmi_remove,
113		.notify = acpi_wmi_notify,
114	},
115};
116
117/*
118 * GUID parsing functions
119 */
120
121/**
122 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
123 * @src:  Pointer to at least 2 characters to convert.
124 *
125 * Convert a two character ASCII hex string to a number.
126 *
127 * Return:  0-255  Success, the byte was parsed correctly
128 *          -1     Error, an invalid character was supplied
129 */
130static int wmi_parse_hexbyte(const u8 *src)
131{
132	int h;
133	int value;
134
135	/* high part */
136	h = value = hex_to_bin(src[0]);
137	if (value < 0)
138		return -1;
139
140	/* low part */
141	value = hex_to_bin(src[1]);
142	if (value >= 0)
143		return (h << 4) | value;
144	return -1;
145}
146
147/**
148 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
149 * @src:   Memory block holding binary GUID (16 bytes)
150 * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
151 *
152 * Byte swap a binary GUID to match it's real GUID value
153 */
154static void wmi_swap_bytes(u8 *src, u8 *dest)
155{
156	int i;
157
158	for (i = 0; i <= 3; i++)
159		memcpy(dest + i, src + (3 - i), 1);
160
161	for (i = 0; i <= 1; i++)
162		memcpy(dest + 4 + i, src + (5 - i), 1);
163
164	for (i = 0; i <= 1; i++)
165		memcpy(dest + 6 + i, src + (7 - i), 1);
166
167	memcpy(dest + 8, src + 8, 8);
168}
169
170/**
171 * wmi_parse_guid - Convert GUID from ASCII to binary
172 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
173 * @dest:  Memory block to hold binary GUID (16 bytes)
174 *
175 * N.B. The GUID need not be NULL terminated.
176 *
177 * Return:  'true'   @dest contains binary GUID
178 *          'false'  @dest contents are undefined
179 */
180static bool wmi_parse_guid(const u8 *src, u8 *dest)
181{
182	static const int size[] = { 4, 2, 2, 2, 6 };
183	int i, j, v;
184
185	if (src[8]  != '-' || src[13] != '-' ||
186		src[18] != '-' || src[23] != '-')
187		return false;
188
189	for (j = 0; j < 5; j++, src++) {
190		for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
191			v = wmi_parse_hexbyte(src);
192			if (v < 0)
193				return false;
194		}
195	}
196
197	return true;
198}
199
200/*
201 * Convert a raw GUID to the ACII string representation
202 */
203static int wmi_gtoa(const char *in, char *out)
204{
205	int i;
206
207	for (i = 3; i >= 0; i--)
208		out += sprintf(out, "%02X", in[i] & 0xFF);
209
210	out += sprintf(out, "-");
211	out += sprintf(out, "%02X", in[5] & 0xFF);
212	out += sprintf(out, "%02X", in[4] & 0xFF);
213	out += sprintf(out, "-");
214	out += sprintf(out, "%02X", in[7] & 0xFF);
215	out += sprintf(out, "%02X", in[6] & 0xFF);
216	out += sprintf(out, "-");
217	out += sprintf(out, "%02X", in[8] & 0xFF);
218	out += sprintf(out, "%02X", in[9] & 0xFF);
219	out += sprintf(out, "-");
220
221	for (i = 10; i <= 15; i++)
222		out += sprintf(out, "%02X", in[i] & 0xFF);
223
224	*out = '\0';
225	return 0;
226}
227
228static bool find_guid(const char *guid_string, struct wmi_block **out)
229{
230	char tmp[16], guid_input[16];
231	struct wmi_block *wblock;
232	struct guid_block *block;
233	struct list_head *p;
234
235	wmi_parse_guid(guid_string, tmp);
236	wmi_swap_bytes(tmp, guid_input);
237
238	list_for_each(p, &wmi_block_list) {
239		wblock = list_entry(p, struct wmi_block, list);
240		block = &wblock->gblock;
241
242		if (memcmp(block->guid, guid_input, 16) == 0) {
243			if (out)
244				*out = wblock;
245			return 1;
246		}
247	}
248	return 0;
249}
250
251static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
252{
253	struct guid_block *block = NULL;
254	char method[5];
255	struct acpi_object_list input;
256	union acpi_object params[1];
257	acpi_status status;
258	acpi_handle handle;
259
260	block = &wblock->gblock;
261	handle = wblock->handle;
262
263	if (!block)
264		return AE_NOT_EXIST;
265
266	input.count = 1;
267	input.pointer = params;
268	params[0].type = ACPI_TYPE_INTEGER;
269	params[0].integer.value = enable;
270
271	snprintf(method, 5, "WE%02X", block->notify_id);
272	status = acpi_evaluate_object(handle, method, &input, NULL);
273
274	if (status != AE_OK && status != AE_NOT_FOUND)
275		return status;
276	else
277		return AE_OK;
278}
279
280/*
281 * Exported WMI functions
282 */
283/**
284 * wmi_evaluate_method - Evaluate a WMI method
285 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
286 * @instance: Instance index
287 * @method_id: Method ID to call
288 * &in: Buffer containing input for the method call
289 * &out: Empty buffer to return the method results
290 *
291 * Call an ACPI-WMI method
292 */
293acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
294u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
295{
296	struct guid_block *block = NULL;
297	struct wmi_block *wblock = NULL;
298	acpi_handle handle;
299	acpi_status status;
300	struct acpi_object_list input;
301	union acpi_object params[3];
302	char method[5] = "WM";
303
304	if (!find_guid(guid_string, &wblock))
305		return AE_ERROR;
306
307	block = &wblock->gblock;
308	handle = wblock->handle;
309
310	if (!(block->flags & ACPI_WMI_METHOD))
311		return AE_BAD_DATA;
312
313	if (block->instance_count < instance)
314		return AE_BAD_PARAMETER;
315
316	input.count = 2;
317	input.pointer = params;
318	params[0].type = ACPI_TYPE_INTEGER;
319	params[0].integer.value = instance;
320	params[1].type = ACPI_TYPE_INTEGER;
321	params[1].integer.value = method_id;
322
323	if (in) {
324		input.count = 3;
325
326		if (block->flags & ACPI_WMI_STRING) {
327			params[2].type = ACPI_TYPE_STRING;
328		} else {
329			params[2].type = ACPI_TYPE_BUFFER;
330		}
331		params[2].buffer.length = in->length;
332		params[2].buffer.pointer = in->pointer;
333	}
334
335	strncat(method, block->object_id, 2);
336
337	status = acpi_evaluate_object(handle, method, &input, out);
338
339	return status;
340}
341EXPORT_SYMBOL_GPL(wmi_evaluate_method);
342
343/**
344 * wmi_query_block - Return contents of a WMI block
345 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
346 * @instance: Instance index
347 * &out: Empty buffer to return the contents of the data block to
348 *
349 * Return the contents of an ACPI-WMI data block to a buffer
350 */
351acpi_status wmi_query_block(const char *guid_string, u8 instance,
352struct acpi_buffer *out)
353{
354	struct guid_block *block = NULL;
355	struct wmi_block *wblock = NULL;
356	acpi_handle handle, wc_handle;
357	acpi_status status, wc_status = AE_ERROR;
358	struct acpi_object_list input, wc_input;
359	union acpi_object wc_params[1], wq_params[1];
360	char method[5];
361	char wc_method[5] = "WC";
362
363	if (!guid_string || !out)
364		return AE_BAD_PARAMETER;
365
366	if (!find_guid(guid_string, &wblock))
367		return AE_ERROR;
368
369	block = &wblock->gblock;
370	handle = wblock->handle;
371
372	if (block->instance_count < instance)
373		return AE_BAD_PARAMETER;
374
375	/* Check GUID is a data block */
376	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
377		return AE_ERROR;
378
379	input.count = 1;
380	input.pointer = wq_params;
381	wq_params[0].type = ACPI_TYPE_INTEGER;
382	wq_params[0].integer.value = instance;
383
384	/*
385	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
386	 * enable collection.
387	 */
388	if (block->flags & ACPI_WMI_EXPENSIVE) {
389		wc_input.count = 1;
390		wc_input.pointer = wc_params;
391		wc_params[0].type = ACPI_TYPE_INTEGER;
392		wc_params[0].integer.value = 1;
393
394		strncat(wc_method, block->object_id, 2);
395
396		/*
397		 * Some GUIDs break the specification by declaring themselves
398		 * expensive, but have no corresponding WCxx method. So we
399		 * should not fail if this happens.
400		 */
401		wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
402		if (ACPI_SUCCESS(wc_status))
403			wc_status = acpi_evaluate_object(handle, wc_method,
404				&wc_input, NULL);
405	}
406
407	strcpy(method, "WQ");
408	strncat(method, block->object_id, 2);
409
410	status = acpi_evaluate_object(handle, method, &input, out);
411
412	/*
413	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
414	 * the WQxx method failed - we should disable collection anyway.
415	 */
416	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
417		wc_params[0].integer.value = 0;
418		status = acpi_evaluate_object(handle,
419		wc_method, &wc_input, NULL);
420	}
421
422	return status;
423}
424EXPORT_SYMBOL_GPL(wmi_query_block);
425
426/**
427 * wmi_set_block - Write to a WMI block
428 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
429 * @instance: Instance index
430 * &in: Buffer containing new values for the data block
431 *
432 * Write the contents of the input buffer to an ACPI-WMI data block
433 */
434acpi_status wmi_set_block(const char *guid_string, u8 instance,
435const struct acpi_buffer *in)
436{
437	struct guid_block *block = NULL;
438	struct wmi_block *wblock = NULL;
439	acpi_handle handle;
440	struct acpi_object_list input;
441	union acpi_object params[2];
442	char method[5] = "WS";
443
444	if (!guid_string || !in)
445		return AE_BAD_DATA;
446
447	if (!find_guid(guid_string, &wblock))
448		return AE_ERROR;
449
450	block = &wblock->gblock;
451	handle = wblock->handle;
452
453	if (block->instance_count < instance)
454		return AE_BAD_PARAMETER;
455
456	/* Check GUID is a data block */
457	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
458		return AE_ERROR;
459
460	input.count = 2;
461	input.pointer = params;
462	params[0].type = ACPI_TYPE_INTEGER;
463	params[0].integer.value = instance;
464
465	if (block->flags & ACPI_WMI_STRING) {
466		params[1].type = ACPI_TYPE_STRING;
467	} else {
468		params[1].type = ACPI_TYPE_BUFFER;
469	}
470	params[1].buffer.length = in->length;
471	params[1].buffer.pointer = in->pointer;
472
473	strncat(method, block->object_id, 2);
474
475	return acpi_evaluate_object(handle, method, &input, NULL);
476}
477EXPORT_SYMBOL_GPL(wmi_set_block);
478
479static void wmi_dump_wdg(const struct guid_block *g)
480{
481	char guid_string[37];
482
483	wmi_gtoa(g->guid, guid_string);
484
485	pr_info("%s:\n", guid_string);
486	pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
487	pr_info("\tnotify_id: %02X\n", g->notify_id);
488	pr_info("\treserved: %02X\n", g->reserved);
489	pr_info("\tinstance_count: %d\n", g->instance_count);
490	pr_info("\tflags: %#x", g->flags);
491	if (g->flags) {
492		if (g->flags & ACPI_WMI_EXPENSIVE)
493			pr_cont(" ACPI_WMI_EXPENSIVE");
494		if (g->flags & ACPI_WMI_METHOD)
495			pr_cont(" ACPI_WMI_METHOD");
496		if (g->flags & ACPI_WMI_STRING)
497			pr_cont(" ACPI_WMI_STRING");
498		if (g->flags & ACPI_WMI_EVENT)
499			pr_cont(" ACPI_WMI_EVENT");
500	}
501	pr_cont("\n");
502
503}
504
505static void wmi_notify_debug(u32 value, void *context)
506{
507	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
508	union acpi_object *obj;
509	acpi_status status;
510
511	status = wmi_get_event_data(value, &response);
512	if (status != AE_OK) {
513		pr_info("bad event status 0x%x\n", status);
514		return;
515	}
516
517	obj = (union acpi_object *)response.pointer;
518
519	if (!obj)
520		return;
521
522	pr_info("DEBUG Event ");
523	switch(obj->type) {
524	case ACPI_TYPE_BUFFER:
525		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
526		break;
527	case ACPI_TYPE_STRING:
528		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
529		break;
530	case ACPI_TYPE_INTEGER:
531		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
532		break;
533	case ACPI_TYPE_PACKAGE:
534		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
535		break;
536	default:
537		pr_cont("object type 0x%X\n", obj->type);
538	}
539	kfree(obj);
540}
541
542/**
543 * wmi_install_notify_handler - Register handler for WMI events
544 * @handler: Function to handle notifications
545 * @data: Data to be returned to handler when event is fired
546 *
547 * Register a handler for events sent to the ACPI-WMI mapper device.
548 */
549acpi_status wmi_install_notify_handler(const char *guid,
550wmi_notify_handler handler, void *data)
551{
552	struct wmi_block *block;
553	acpi_status status = AE_NOT_EXIST;
554	char tmp[16], guid_input[16];
555	struct list_head *p;
556
557	if (!guid || !handler)
558		return AE_BAD_PARAMETER;
559
560	wmi_parse_guid(guid, tmp);
561	wmi_swap_bytes(tmp, guid_input);
562
563	list_for_each(p, &wmi_block_list) {
564		acpi_status wmi_status;
565		block = list_entry(p, struct wmi_block, list);
566
567		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
568			if (block->handler &&
569			    block->handler != wmi_notify_debug)
570				return AE_ALREADY_ACQUIRED;
571
572			block->handler = handler;
573			block->handler_data = data;
574
575			wmi_status = wmi_method_enable(block, 1);
576			if ((wmi_status != AE_OK) ||
577			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
578				status = wmi_status;
579		}
580	}
581
582	return status;
583}
584EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
585
586/**
587 * wmi_uninstall_notify_handler - Unregister handler for WMI events
588 *
589 * Unregister handler for events sent to the ACPI-WMI mapper device.
590 */
591acpi_status wmi_remove_notify_handler(const char *guid)
592{
593	struct wmi_block *block;
594	acpi_status status = AE_NOT_EXIST;
595	char tmp[16], guid_input[16];
596	struct list_head *p;
597
598	if (!guid)
599		return AE_BAD_PARAMETER;
600
601	wmi_parse_guid(guid, tmp);
602	wmi_swap_bytes(tmp, guid_input);
603
604	list_for_each(p, &wmi_block_list) {
605		acpi_status wmi_status;
606		block = list_entry(p, struct wmi_block, list);
607
608		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
609			if (!block->handler ||
610			    block->handler == wmi_notify_debug)
611				return AE_NULL_ENTRY;
612
613			if (debug_event) {
614				block->handler = wmi_notify_debug;
615				status = AE_OK;
616			} else {
617				wmi_status = wmi_method_enable(block, 0);
618				block->handler = NULL;
619				block->handler_data = NULL;
620				if ((wmi_status != AE_OK) ||
621				    ((wmi_status == AE_OK) &&
622				     (status == AE_NOT_EXIST)))
623					status = wmi_status;
624			}
625		}
626	}
627
628	return status;
629}
630EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
631
632/**
633 * wmi_get_event_data - Get WMI data associated with an event
634 *
635 * @event: Event to find
636 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
637 *
638 * Returns extra data associated with an event in WMI.
639 */
640acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
641{
642	struct acpi_object_list input;
643	union acpi_object params[1];
644	struct guid_block *gblock;
645	struct wmi_block *wblock;
646	struct list_head *p;
647
648	input.count = 1;
649	input.pointer = params;
650	params[0].type = ACPI_TYPE_INTEGER;
651	params[0].integer.value = event;
652
653	list_for_each(p, &wmi_block_list) {
654		wblock = list_entry(p, struct wmi_block, list);
655		gblock = &wblock->gblock;
656
657		if ((gblock->flags & ACPI_WMI_EVENT) &&
658			(gblock->notify_id == event))
659			return acpi_evaluate_object(wblock->handle, "_WED",
660				&input, out);
661	}
662
663	return AE_NOT_FOUND;
664}
665EXPORT_SYMBOL_GPL(wmi_get_event_data);
666
667/**
668 * wmi_has_guid - Check if a GUID is available
669 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
670 *
671 * Check if a given GUID is defined by _WDG
672 */
673bool wmi_has_guid(const char *guid_string)
674{
675	return find_guid(guid_string, NULL);
676}
677EXPORT_SYMBOL_GPL(wmi_has_guid);
678
679/*
680 * sysfs interface
681 */
682static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
683			     char *buf)
684{
685	char guid_string[37];
686	struct wmi_block *wblock;
687
688	wblock = dev_get_drvdata(dev);
689	if (!wblock)
690		return -ENOMEM;
 
 
691
692	wmi_gtoa(wblock->gblock.guid, guid_string);
693
694	return sprintf(buf, "wmi:%s\n", guid_string);
695}
 
696
697static struct device_attribute wmi_dev_attrs[] = {
698	__ATTR_RO(modalias),
699	__ATTR_NULL
700};
 
701
702static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
703{
704	char guid_string[37];
705
706	struct wmi_block *wblock;
707
708	if (add_uevent_var(env, "MODALIAS="))
709		return -ENOMEM;
710
711	wblock = dev_get_drvdata(dev);
712	if (!wblock)
713		return -ENOMEM;
714
715	wmi_gtoa(wblock->gblock.guid, guid_string);
716
717	strcpy(&env->buf[env->buflen - 1], "wmi:");
718	memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
719	env->buflen += 40;
720
721	return 0;
722}
723
724static void wmi_dev_free(struct device *dev)
725{
726	struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
727
728	kfree(wmi_block);
729}
730
731static struct class wmi_class = {
732	.name = "wmi",
733	.dev_release = wmi_dev_free,
734	.dev_uevent = wmi_dev_uevent,
735	.dev_attrs = wmi_dev_attrs,
736};
737
738static int wmi_create_device(const struct guid_block *gblock,
739			     struct wmi_block *wblock, acpi_handle handle)
740{
741	char guid_string[37];
742
743	wblock->dev.class = &wmi_class;
744
745	wmi_gtoa(gblock->guid, guid_string);
746	dev_set_name(&wblock->dev, guid_string);
747
748	dev_set_drvdata(&wblock->dev, wblock);
749
750	return device_register(&wblock->dev);
751}
752
753static void wmi_free_devices(void)
754{
755	struct wmi_block *wblock, *next;
756
757	/* Delete devices for all the GUIDs */
758	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
759		list_del(&wblock->list);
760		if (wblock->dev.class)
761			device_unregister(&wblock->dev);
762		else
763			kfree(wblock);
764	}
765}
766
767static bool guid_already_parsed(const char *guid_string)
768{
769	struct wmi_block *wblock;
770
771	list_for_each_entry(wblock, &wmi_block_list, list)
772		if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
773			return true;
774
775	return false;
776}
777
778/*
779 * Parse the _WDG method for the GUID data blocks
780 */
781static acpi_status parse_wdg(acpi_handle handle)
782{
783	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
784	union acpi_object *obj;
785	const struct guid_block *gblock;
786	struct wmi_block *wblock;
787	acpi_status status;
788	int retval;
789	u32 i, total;
790
791	status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
792	if (ACPI_FAILURE(status))
793		return -ENXIO;
794
795	obj = (union acpi_object *) out.pointer;
796	if (!obj)
797		return -ENXIO;
798
799	if (obj->type != ACPI_TYPE_BUFFER) {
800		retval = -ENXIO;
801		goto out_free_pointer;
802	}
803
804	gblock = (const struct guid_block *)obj->buffer.pointer;
805	total = obj->buffer.length / sizeof(struct guid_block);
806
807	for (i = 0; i < total; i++) {
808		if (debug_dump_wdg)
809			wmi_dump_wdg(&gblock[i]);
810
811		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
812		if (!wblock)
813			return AE_NO_MEMORY;
814
815		wblock->handle = handle;
816		wblock->gblock = gblock[i];
817
818		/*
819		  Some WMI devices, like those for nVidia hooks, have a
820		  duplicate GUID. It's not clear what we should do in this
821		  case yet, so for now, we'll just ignore the duplicate
822		  for device creation.
823		*/
824		if (!guid_already_parsed(gblock[i].guid)) {
825			retval = wmi_create_device(&gblock[i], wblock, handle);
826			if (retval) {
827				wmi_free_devices();
828				goto out_free_pointer;
829			}
830		}
831
832		list_add_tail(&wblock->list, &wmi_block_list);
833
834		if (debug_event) {
835			wblock->handler = wmi_notify_debug;
836			wmi_method_enable(wblock, 1);
837		}
838	}
839
840	retval = 0;
841
842out_free_pointer:
843	kfree(out.pointer);
844
845	return retval;
846}
847
848/*
849 * WMI can have EmbeddedControl access regions. In which case, we just want to
850 * hand these off to the EC driver.
851 */
852static acpi_status
853acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
854		      u32 bits, u64 *value,
855		      void *handler_context, void *region_context)
856{
857	int result = 0, i = 0;
858	u8 temp = 0;
859
860	if ((address > 0xFF) || !value)
861		return AE_BAD_PARAMETER;
862
863	if (function != ACPI_READ && function != ACPI_WRITE)
864		return AE_BAD_PARAMETER;
865
866	if (bits != 8)
867		return AE_BAD_PARAMETER;
868
869	if (function == ACPI_READ) {
870		result = ec_read(address, &temp);
871		(*value) |= ((u64)temp) << i;
872	} else {
873		temp = 0xff & ((*value) >> i);
874		result = ec_write(address, temp);
875	}
876
877	switch (result) {
878	case -EINVAL:
879		return AE_BAD_PARAMETER;
880		break;
881	case -ENODEV:
882		return AE_NOT_FOUND;
883		break;
884	case -ETIME:
885		return AE_TIME;
886		break;
887	default:
888		return AE_OK;
889	}
890}
891
892static void acpi_wmi_notify(struct acpi_device *device, u32 event)
893{
894	struct guid_block *block;
895	struct wmi_block *wblock;
896	struct list_head *p;
897	char guid_string[37];
898
899	list_for_each(p, &wmi_block_list) {
900		wblock = list_entry(p, struct wmi_block, list);
901		block = &wblock->gblock;
902
903		if ((block->flags & ACPI_WMI_EVENT) &&
904			(block->notify_id == event)) {
905			if (wblock->handler)
906				wblock->handler(event, wblock->handler_data);
907			if (debug_event) {
908				wmi_gtoa(wblock->gblock.guid, guid_string);
909				pr_info("DEBUG Event GUID: %s\n", guid_string);
910			}
911
912			acpi_bus_generate_netlink_event(
913				device->pnp.device_class, dev_name(&device->dev),
914				event, 0);
915			break;
916		}
917	}
918}
919
920static int acpi_wmi_remove(struct acpi_device *device, int type)
921{
922	acpi_remove_address_space_handler(device->handle,
923				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
924	wmi_free_devices();
925
926	return 0;
927}
928
929static int acpi_wmi_add(struct acpi_device *device)
930{
931	acpi_status status;
932	int error;
933
934	status = acpi_install_address_space_handler(device->handle,
935						    ACPI_ADR_SPACE_EC,
936						    &acpi_wmi_ec_space_handler,
937						    NULL, NULL);
938	if (ACPI_FAILURE(status)) {
939		pr_err("Error installing EC region handler\n");
940		return -ENODEV;
941	}
942
943	error = parse_wdg(device->handle);
944	if (error) {
945		acpi_remove_address_space_handler(device->handle,
946						  ACPI_ADR_SPACE_EC,
947						  &acpi_wmi_ec_space_handler);
948		pr_err("Failed to parse WDG method\n");
949		return error;
950	}
951
952	return 0;
953}
954
955static int __init acpi_wmi_init(void)
956{
957	int error;
958
959	if (acpi_disabled)
960		return -ENODEV;
961
962	error = class_register(&wmi_class);
963	if (error)
964		return error;
965
966	error = acpi_bus_register_driver(&acpi_wmi_driver);
967	if (error) {
968		pr_err("Error loading mapper\n");
969		class_unregister(&wmi_class);
970		return error;
971	}
972
973	pr_info("Mapper loaded\n");
974	return 0;
975}
976
977static void __exit acpi_wmi_exit(void)
978{
979	acpi_bus_unregister_driver(&acpi_wmi_driver);
980	class_unregister(&wmi_class);
981
982	pr_info("Mapper unloaded\n");
983}
984
985subsys_initcall(acpi_wmi_init);
986module_exit(acpi_wmi_exit);
v3.15
  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);