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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);
v3.5.6
  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);