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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);
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  ACPI-WMI mapping driver
   4 *
   5 *  Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
   6 *
   7 *  GUID parsing code from ldm.c is:
   8 *   Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
   9 *   Copyright (c) 2001-2007 Anton Altaparmakov
  10 *   Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
  11 *
  12 *  WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
  13 *    Copyright (C) 2015 Andrew Lutomirski
  14 *    Copyright (C) 2017 VMware, Inc. All Rights Reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  15 */
  16
  17#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
  18
  19#include <linux/acpi.h>
 
 
  20#include <linux/device.h>
  21#include <linux/init.h>
  22#include <linux/kernel.h>
  23#include <linux/list.h>
  24#include <linux/miscdevice.h>
 
  25#include <linux/module.h>
  26#include <linux/platform_device.h>
  27#include <linux/slab.h>
  28#include <linux/types.h>
  29#include <linux/uaccess.h>
  30#include <linux/uuid.h>
  31#include <linux/wmi.h>
  32#include <linux/fs.h>
  33#include <uapi/linux/wmi.h>
  34
 
  35MODULE_AUTHOR("Carlos Corbacho");
  36MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
  37MODULE_LICENSE("GPL");
  38
 
 
  39static LIST_HEAD(wmi_block_list);
  40
  41struct guid_block {
  42	char guid[16];
  43	union {
  44		char object_id[2];
  45		struct {
  46			unsigned char notify_id;
  47			unsigned char reserved;
  48		};
  49	};
  50	u8 instance_count;
  51	u8 flags;
  52};
  53
  54struct wmi_block {
  55	struct wmi_device dev;
  56	struct list_head list;
  57	struct guid_block gblock;
  58	struct miscdevice char_dev;
  59	struct mutex char_mutex;
  60	struct acpi_device *acpi_device;
  61	wmi_notify_handler handler;
  62	void *handler_data;
  63	u64 req_buf_size;
  64
  65	bool read_takes_no_args;
  66};
  67
  68
  69/*
  70 * If the GUID data block is marked as expensive, we must enable and
  71 * explicitily disable data collection.
  72 */
  73#define ACPI_WMI_EXPENSIVE   0x1
  74#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
  75#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
  76#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
  77
  78static bool debug_event;
  79module_param(debug_event, bool, 0444);
  80MODULE_PARM_DESC(debug_event,
  81		 "Log WMI Events [0/1]");
  82
  83static bool debug_dump_wdg;
  84module_param(debug_dump_wdg, bool, 0444);
  85MODULE_PARM_DESC(debug_dump_wdg,
  86		 "Dump available WMI interfaces [0/1]");
  87
  88static int acpi_wmi_remove(struct platform_device *device);
  89static int acpi_wmi_probe(struct platform_device *device);
 
  90
  91static const struct acpi_device_id wmi_device_ids[] = {
  92	{"PNP0C14", 0},
  93	{"pnp0c14", 0},
  94	{"", 0},
  95};
  96MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
  97
  98static struct platform_driver acpi_wmi_driver = {
  99	.driver = {
 100		.name = "acpi-wmi",
 101		.acpi_match_table = wmi_device_ids,
 
 
 
 
 102	},
 103	.probe = acpi_wmi_probe,
 104	.remove = acpi_wmi_remove,
 105};
 106
 107/*
 108 * GUID parsing functions
 109 */
 110
 111static bool find_guid(const char *guid_string, struct wmi_block **out)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 112{
 113	guid_t guid_input;
 114	struct wmi_block *wblock;
 115	struct guid_block *block;
 
 116
 117	if (guid_parse(guid_string, &guid_input))
 118		return false;
 119
 120	list_for_each_entry(wblock, &wmi_block_list, list) {
 121		block = &wblock->gblock;
 122
 123		if (memcmp(block->guid, &guid_input, 16) == 0) {
 124			if (out)
 125				*out = wblock;
 126			return true;
 127		}
 128	}
 129	return false;
 130}
 131
 132static const void *find_guid_context(struct wmi_block *wblock,
 133				      struct wmi_driver *wdriver)
 
 
 
 
 
 
 
 
 
 134{
 135	const struct wmi_device_id *id;
 136	guid_t guid_input;
 137
 138	if (wblock == NULL || wdriver == NULL)
 139		return NULL;
 140	if (wdriver->id_table == NULL)
 141		return NULL;
 142
 143	id = wdriver->id_table;
 144	while (*id->guid_string) {
 145		if (guid_parse(id->guid_string, &guid_input))
 146			continue;
 147		if (!memcmp(wblock->gblock.guid, &guid_input, 16))
 148			return id->context;
 149		id++;
 150	}
 151	return NULL;
 
 152}
 153
 154static int get_subobj_info(acpi_handle handle, const char *pathname,
 155			   struct acpi_device_info **info)
 156{
 157	struct acpi_device_info *dummy_info, **info_ptr;
 158	acpi_handle subobj_handle;
 159	acpi_status status;
 
 160
 161	status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
 162	if (status == AE_NOT_FOUND)
 163		return -ENOENT;
 164	else if (ACPI_FAILURE(status))
 165		return -EIO;
 166
 167	info_ptr = info ? info : &dummy_info;
 168	status = acpi_get_object_info(subobj_handle, info_ptr);
 169	if (ACPI_FAILURE(status))
 170		return -EIO;
 171
 172	if (!info)
 173		kfree(dummy_info);
 174
 175	return 0;
 
 
 
 176}
 177
 178static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
 179{
 180	struct guid_block *block = NULL;
 181	char method[5];
 182	acpi_status status;
 183	acpi_handle handle;
 184
 185	block = &wblock->gblock;
 186	handle = wblock->acpi_device->handle;
 187
 188	snprintf(method, 5, "WE%02X", block->notify_id);
 189	status = acpi_execute_simple_method(handle, method, enable);
 190
 191	if (status != AE_OK && status != AE_NOT_FOUND)
 192		return status;
 193	else
 194		return AE_OK;
 195}
 196
 197/*
 198 * Exported WMI functions
 199 */
 200
 201/**
 202 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
 203 * @wdev: A wmi bus device from a driver
 204 * @length: Required buffer size
 205 *
 206 * Allocates memory needed for buffer, stores the buffer size in that memory
 207 */
 208int set_required_buffer_size(struct wmi_device *wdev, u64 length)
 209{
 210	struct wmi_block *wblock;
 211
 212	wblock = container_of(wdev, struct wmi_block, dev);
 213	wblock->req_buf_size = length;
 214
 215	return 0;
 216}
 217EXPORT_SYMBOL_GPL(set_required_buffer_size);
 218
 219/**
 220 * wmi_evaluate_method - Evaluate a WMI method
 221 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 222 * @instance: Instance index
 223 * @method_id: Method ID to call
 224 * @in: Buffer containing input for the method call
 225 * @out: Empty buffer to return the method results
 226 *
 227 * Call an ACPI-WMI method
 228 */
 229acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
 230u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 231{
 232	struct wmi_block *wblock = NULL;
 233
 234	if (!find_guid(guid_string, &wblock))
 235		return AE_ERROR;
 236	return wmidev_evaluate_method(&wblock->dev, instance, method_id,
 237				      in, out);
 238}
 239EXPORT_SYMBOL_GPL(wmi_evaluate_method);
 240
 241/**
 242 * wmidev_evaluate_method - Evaluate a WMI method
 243 * @wdev: A wmi bus device from a driver
 244 * @instance: Instance index
 245 * @method_id: Method ID to call
 246 * @in: Buffer containing input for the method call
 247 * @out: Empty buffer to return the method results
 248 *
 249 * Call an ACPI-WMI method
 250 */
 251acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
 252	u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 253{
 254	struct guid_block *block = NULL;
 255	struct wmi_block *wblock = NULL;
 256	acpi_handle handle;
 257	acpi_status status;
 258	struct acpi_object_list input;
 259	union acpi_object params[3];
 260	char method[5] = "WM";
 261
 262	wblock = container_of(wdev, struct wmi_block, dev);
 
 
 263	block = &wblock->gblock;
 264	handle = wblock->acpi_device->handle;
 265
 266	if (!(block->flags & ACPI_WMI_METHOD))
 267		return AE_BAD_DATA;
 268
 269	if (block->instance_count <= instance)
 270		return AE_BAD_PARAMETER;
 271
 272	input.count = 2;
 273	input.pointer = params;
 274	params[0].type = ACPI_TYPE_INTEGER;
 275	params[0].integer.value = instance;
 276	params[1].type = ACPI_TYPE_INTEGER;
 277	params[1].integer.value = method_id;
 278
 279	if (in) {
 280		input.count = 3;
 281
 282		if (block->flags & ACPI_WMI_STRING) {
 283			params[2].type = ACPI_TYPE_STRING;
 284		} else {
 285			params[2].type = ACPI_TYPE_BUFFER;
 286		}
 287		params[2].buffer.length = in->length;
 288		params[2].buffer.pointer = in->pointer;
 289	}
 290
 291	strncat(method, block->object_id, 2);
 292
 293	status = acpi_evaluate_object(handle, method, &input, out);
 294
 295	return status;
 296}
 297EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
 298
 299static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
 300				 struct acpi_buffer *out)
 
 
 
 
 
 
 
 
 301{
 302	struct guid_block *block = NULL;
 
 303	acpi_handle handle;
 304	acpi_status status, wc_status = AE_ERROR;
 305	struct acpi_object_list input;
 306	union acpi_object wq_params[1];
 307	char method[5];
 308	char wc_method[5] = "WC";
 309
 310	if (!out)
 311		return AE_BAD_PARAMETER;
 312
 
 
 
 313	block = &wblock->gblock;
 314	handle = wblock->acpi_device->handle;
 315
 316	if (block->instance_count <= instance)
 317		return AE_BAD_PARAMETER;
 318
 319	/* Check GUID is a data block */
 320	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 321		return AE_ERROR;
 322
 323	input.count = 1;
 324	input.pointer = wq_params;
 325	wq_params[0].type = ACPI_TYPE_INTEGER;
 326	wq_params[0].integer.value = instance;
 327
 328	if (instance == 0 && wblock->read_takes_no_args)
 329		input.count = 0;
 330
 331	/*
 332	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
 333	 * enable collection.
 334	 */
 335	if (block->flags & ACPI_WMI_EXPENSIVE) {
 336		strncat(wc_method, block->object_id, 2);
 337
 338		/*
 339		 * Some GUIDs break the specification by declaring themselves
 340		 * expensive, but have no corresponding WCxx method. So we
 341		 * should not fail if this happens.
 342		 */
 343		wc_status = acpi_execute_simple_method(handle, wc_method, 1);
 
 
 344	}
 345
 346	strcpy(method, "WQ");
 347	strncat(method, block->object_id, 2);
 348
 349	status = acpi_evaluate_object(handle, method, &input, out);
 350
 351	/*
 352	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
 353	 * the WQxx method failed - we should disable collection anyway.
 354	 */
 355	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
 356		status = acpi_execute_simple_method(handle, wc_method, 0);
 357	}
 358
 359	return status;
 360}
 361
 362/**
 363 * wmi_query_block - Return contents of a WMI block (deprecated)
 364 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 365 * @instance: Instance index
 366 * @out: Empty buffer to return the contents of the data block to
 367 *
 368 * Return the contents of an ACPI-WMI data block to a buffer
 369 */
 370acpi_status wmi_query_block(const char *guid_string, u8 instance,
 371			    struct acpi_buffer *out)
 372{
 373	struct wmi_block *wblock;
 374
 375	if (!guid_string)
 376		return AE_BAD_PARAMETER;
 377
 378	if (!find_guid(guid_string, &wblock))
 379		return AE_ERROR;
 380
 381	return __query_block(wblock, instance, out);
 382}
 383EXPORT_SYMBOL_GPL(wmi_query_block);
 384
 385union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
 386{
 387	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
 388	struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
 389
 390	if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
 391		return NULL;
 392
 393	return (union acpi_object *)out.pointer;
 394}
 395EXPORT_SYMBOL_GPL(wmidev_block_query);
 396
 397/**
 398 * wmi_set_block - Write to a WMI block
 399 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 400 * @instance: Instance index
 401 * @in: Buffer containing new values for the data block
 402 *
 403 * Write the contents of the input buffer to an ACPI-WMI data block
 404 */
 405acpi_status wmi_set_block(const char *guid_string, u8 instance,
 406			  const struct acpi_buffer *in)
 407{
 408	struct guid_block *block = NULL;
 409	struct wmi_block *wblock = NULL;
 410	acpi_handle handle;
 411	struct acpi_object_list input;
 412	union acpi_object params[2];
 413	char method[5] = "WS";
 414
 415	if (!guid_string || !in)
 416		return AE_BAD_DATA;
 417
 418	if (!find_guid(guid_string, &wblock))
 419		return AE_ERROR;
 420
 421	block = &wblock->gblock;
 422	handle = wblock->acpi_device->handle;
 423
 424	if (block->instance_count <= instance)
 425		return AE_BAD_PARAMETER;
 426
 427	/* Check GUID is a data block */
 428	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 429		return AE_ERROR;
 430
 431	input.count = 2;
 432	input.pointer = params;
 433	params[0].type = ACPI_TYPE_INTEGER;
 434	params[0].integer.value = instance;
 435
 436	if (block->flags & ACPI_WMI_STRING) {
 437		params[1].type = ACPI_TYPE_STRING;
 438	} else {
 439		params[1].type = ACPI_TYPE_BUFFER;
 440	}
 441	params[1].buffer.length = in->length;
 442	params[1].buffer.pointer = in->pointer;
 443
 444	strncat(method, block->object_id, 2);
 445
 446	return acpi_evaluate_object(handle, method, &input, NULL);
 447}
 448EXPORT_SYMBOL_GPL(wmi_set_block);
 449
 450static void wmi_dump_wdg(const struct guid_block *g)
 451{
 452	pr_info("%pUL:\n", g->guid);
 453	if (g->flags & ACPI_WMI_EVENT)
 454		pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
 455	else
 456		pr_info("\tobject_id: %2pE\n", g->object_id);
 457	pr_info("\tinstance_count: %d\n", g->instance_count);
 458	pr_info("\tflags: %#x", g->flags);
 459	if (g->flags) {
 460		if (g->flags & ACPI_WMI_EXPENSIVE)
 461			pr_cont(" ACPI_WMI_EXPENSIVE");
 462		if (g->flags & ACPI_WMI_METHOD)
 463			pr_cont(" ACPI_WMI_METHOD");
 464		if (g->flags & ACPI_WMI_STRING)
 465			pr_cont(" ACPI_WMI_STRING");
 466		if (g->flags & ACPI_WMI_EVENT)
 467			pr_cont(" ACPI_WMI_EVENT");
 468	}
 469	pr_cont("\n");
 470
 471}
 472
 473static void wmi_notify_debug(u32 value, void *context)
 474{
 475	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
 476	union acpi_object *obj;
 477	acpi_status status;
 478
 479	status = wmi_get_event_data(value, &response);
 480	if (status != AE_OK) {
 481		pr_info("bad event status 0x%x\n", status);
 482		return;
 483	}
 484
 485	obj = (union acpi_object *)response.pointer;
 486
 487	if (!obj)
 488		return;
 489
 490	pr_info("DEBUG Event ");
 491	switch(obj->type) {
 492	case ACPI_TYPE_BUFFER:
 493		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
 494		break;
 495	case ACPI_TYPE_STRING:
 496		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
 497		break;
 498	case ACPI_TYPE_INTEGER:
 499		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
 500		break;
 501	case ACPI_TYPE_PACKAGE:
 502		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
 503		break;
 504	default:
 505		pr_cont("object type 0x%X\n", obj->type);
 506	}
 507	kfree(obj);
 508}
 509
 510/**
 511 * wmi_install_notify_handler - Register handler for WMI events
 512 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 513 * @handler: Function to handle notifications
 514 * @data: Data to be returned to handler when event is fired
 515 *
 516 * Register a handler for events sent to the ACPI-WMI mapper device.
 517 */
 518acpi_status wmi_install_notify_handler(const char *guid,
 519wmi_notify_handler handler, void *data)
 520{
 521	struct wmi_block *block;
 522	acpi_status status = AE_NOT_EXIST;
 523	guid_t guid_input;
 
 524
 525	if (!guid || !handler)
 526		return AE_BAD_PARAMETER;
 527
 528	if (guid_parse(guid, &guid_input))
 529		return AE_BAD_PARAMETER;
 530
 531	list_for_each_entry(block, &wmi_block_list, list) {
 532		acpi_status wmi_status;
 
 533
 534		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 535			if (block->handler &&
 536			    block->handler != wmi_notify_debug)
 537				return AE_ALREADY_ACQUIRED;
 538
 539			block->handler = handler;
 540			block->handler_data = data;
 541
 542			wmi_status = wmi_method_enable(block, 1);
 543			if ((wmi_status != AE_OK) ||
 544			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
 545				status = wmi_status;
 546		}
 547	}
 548
 549	return status;
 550}
 551EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
 552
 553/**
 554 * wmi_uninstall_notify_handler - Unregister handler for WMI events
 555 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 556 *
 557 * Unregister handler for events sent to the ACPI-WMI mapper device.
 558 */
 559acpi_status wmi_remove_notify_handler(const char *guid)
 560{
 561	struct wmi_block *block;
 562	acpi_status status = AE_NOT_EXIST;
 563	guid_t guid_input;
 
 564
 565	if (!guid)
 566		return AE_BAD_PARAMETER;
 567
 568	if (guid_parse(guid, &guid_input))
 569		return AE_BAD_PARAMETER;
 570
 571	list_for_each_entry(block, &wmi_block_list, list) {
 572		acpi_status wmi_status;
 
 573
 574		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 575			if (!block->handler ||
 576			    block->handler == wmi_notify_debug)
 577				return AE_NULL_ENTRY;
 578
 579			if (debug_event) {
 580				block->handler = wmi_notify_debug;
 581				status = AE_OK;
 582			} else {
 583				wmi_status = wmi_method_enable(block, 0);
 584				block->handler = NULL;
 585				block->handler_data = NULL;
 586				if ((wmi_status != AE_OK) ||
 587				    ((wmi_status == AE_OK) &&
 588				     (status == AE_NOT_EXIST)))
 589					status = wmi_status;
 590			}
 591		}
 592	}
 593
 594	return status;
 595}
 596EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
 597
 598/**
 599 * wmi_get_event_data - Get WMI data associated with an event
 600 *
 601 * @event: Event to find
 602 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
 603 *
 604 * Returns extra data associated with an event in WMI.
 605 */
 606acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
 607{
 608	struct acpi_object_list input;
 609	union acpi_object params[1];
 610	struct guid_block *gblock;
 611	struct wmi_block *wblock;
 
 612
 613	input.count = 1;
 614	input.pointer = params;
 615	params[0].type = ACPI_TYPE_INTEGER;
 616	params[0].integer.value = event;
 617
 618	list_for_each_entry(wblock, &wmi_block_list, list) {
 
 619		gblock = &wblock->gblock;
 620
 621		if ((gblock->flags & ACPI_WMI_EVENT) &&
 622			(gblock->notify_id == event))
 623			return acpi_evaluate_object(wblock->acpi_device->handle,
 624				"_WED", &input, out);
 625	}
 626
 627	return AE_NOT_FOUND;
 628}
 629EXPORT_SYMBOL_GPL(wmi_get_event_data);
 630
 631/**
 632 * wmi_has_guid - Check if a GUID is available
 633 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 634 *
 635 * Check if a given GUID is defined by _WDG
 636 */
 637bool wmi_has_guid(const char *guid_string)
 638{
 639	return find_guid(guid_string, NULL);
 640}
 641EXPORT_SYMBOL_GPL(wmi_has_guid);
 642
 643/**
 644 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
 645 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 646 *
 647 * Find the _UID of ACPI device associated with this WMI GUID.
 648 *
 649 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
 650 */
 651char *wmi_get_acpi_device_uid(const char *guid_string)
 652{
 653	struct wmi_block *wblock = NULL;
 654
 655	if (!find_guid(guid_string, &wblock))
 656		return NULL;
 657
 658	return acpi_device_uid(wblock->acpi_device);
 659}
 660EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
 661
 662static struct wmi_block *dev_to_wblock(struct device *dev)
 663{
 664	return container_of(dev, struct wmi_block, dev.dev);
 665}
 666
 667static struct wmi_device *dev_to_wdev(struct device *dev)
 668{
 669	return container_of(dev, struct wmi_device, dev);
 670}
 671
 672/*
 673 * sysfs interface
 674 */
 675static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 676			     char *buf)
 677{
 678	struct wmi_block *wblock = dev_to_wblock(dev);
 
 
 
 
 
 
 679
 680	return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
 681}
 682static DEVICE_ATTR_RO(modalias);
 683
 684static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
 685			 char *buf)
 686{
 687	struct wmi_block *wblock = dev_to_wblock(dev);
 688
 689	return sprintf(buf, "%pUL\n", wblock->gblock.guid);
 690}
 691static DEVICE_ATTR_RO(guid);
 692
 693static ssize_t instance_count_show(struct device *dev,
 694				   struct device_attribute *attr, char *buf)
 695{
 696	struct wmi_block *wblock = dev_to_wblock(dev);
 697
 698	return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
 699}
 700static DEVICE_ATTR_RO(instance_count);
 701
 702static ssize_t expensive_show(struct device *dev,
 703			      struct device_attribute *attr, char *buf)
 704{
 705	struct wmi_block *wblock = dev_to_wblock(dev);
 706
 707	return sprintf(buf, "%d\n",
 708		       (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
 709}
 710static DEVICE_ATTR_RO(expensive);
 711
 712static struct attribute *wmi_attrs[] = {
 713	&dev_attr_modalias.attr,
 714	&dev_attr_guid.attr,
 715	&dev_attr_instance_count.attr,
 716	&dev_attr_expensive.attr,
 717	NULL,
 718};
 719ATTRIBUTE_GROUPS(wmi);
 720
 721static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
 722			      char *buf)
 723{
 724	struct wmi_block *wblock = dev_to_wblock(dev);
 725
 726	return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
 727}
 728static DEVICE_ATTR_RO(notify_id);
 729
 730static struct attribute *wmi_event_attrs[] = {
 731	&dev_attr_notify_id.attr,
 732	NULL,
 733};
 734ATTRIBUTE_GROUPS(wmi_event);
 735
 736static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
 737			      char *buf)
 738{
 739	struct wmi_block *wblock = dev_to_wblock(dev);
 740
 741	return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
 742		       wblock->gblock.object_id[1]);
 743}
 744static DEVICE_ATTR_RO(object_id);
 745
 746static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
 747			    char *buf)
 748{
 749	struct wmi_device *wdev = dev_to_wdev(dev);
 750
 751	return sprintf(buf, "%d\n", (int)wdev->setable);
 752}
 753static DEVICE_ATTR_RO(setable);
 754
 755static struct attribute *wmi_data_attrs[] = {
 756	&dev_attr_object_id.attr,
 757	&dev_attr_setable.attr,
 758	NULL,
 759};
 760ATTRIBUTE_GROUPS(wmi_data);
 761
 762static struct attribute *wmi_method_attrs[] = {
 763	&dev_attr_object_id.attr,
 764	NULL,
 765};
 766ATTRIBUTE_GROUPS(wmi_method);
 767
 768static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 769{
 770	struct wmi_block *wblock = dev_to_wblock(dev);
 771
 772	if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
 773		return -ENOMEM;
 774
 775	if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
 
 776		return -ENOMEM;
 777
 778	return 0;
 779}
 780
 781static void wmi_dev_release(struct device *dev)
 782{
 783	struct wmi_block *wblock = dev_to_wblock(dev);
 784
 785	kfree(wblock);
 786}
 787
 788static int wmi_dev_match(struct device *dev, struct device_driver *driver)
 789{
 790	struct wmi_driver *wmi_driver =
 791		container_of(driver, struct wmi_driver, driver);
 792	struct wmi_block *wblock = dev_to_wblock(dev);
 793	const struct wmi_device_id *id = wmi_driver->id_table;
 794
 795	if (id == NULL)
 796		return 0;
 797
 798	while (*id->guid_string) {
 799		guid_t driver_guid;
 800
 801		if (WARN_ON(guid_parse(id->guid_string, &driver_guid)))
 802			continue;
 803		if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
 804			return 1;
 805
 806		id++;
 807	}
 808
 809	return 0;
 810}
 811static int wmi_char_open(struct inode *inode, struct file *filp)
 812{
 813	const char *driver_name = filp->f_path.dentry->d_iname;
 814	struct wmi_block *wblock = NULL;
 815	struct wmi_block *next = NULL;
 816
 817	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
 818		if (!wblock->dev.dev.driver)
 819			continue;
 820		if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
 821			filp->private_data = wblock;
 822			break;
 823		}
 824	}
 825
 826	if (!filp->private_data)
 827		return -ENODEV;
 828
 829	return nonseekable_open(inode, filp);
 830}
 831
 832static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
 833	size_t length, loff_t *offset)
 834{
 835	struct wmi_block *wblock = filp->private_data;
 836
 837	return simple_read_from_buffer(buffer, length, offset,
 838				       &wblock->req_buf_size,
 839				       sizeof(wblock->req_buf_size));
 840}
 841
 842static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 843{
 844	struct wmi_ioctl_buffer __user *input =
 845		(struct wmi_ioctl_buffer __user *) arg;
 846	struct wmi_block *wblock = filp->private_data;
 847	struct wmi_ioctl_buffer *buf = NULL;
 848	struct wmi_driver *wdriver = NULL;
 849	int ret;
 850
 851	if (_IOC_TYPE(cmd) != WMI_IOC)
 852		return -ENOTTY;
 853
 854	/* make sure we're not calling a higher instance than exists*/
 855	if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
 856		return -EINVAL;
 857
 858	mutex_lock(&wblock->char_mutex);
 859	buf = wblock->handler_data;
 860	if (get_user(buf->length, &input->length)) {
 861		dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
 862		ret = -EFAULT;
 863		goto out_ioctl;
 864	}
 865	/* if it's too small, abort */
 866	if (buf->length < wblock->req_buf_size) {
 867		dev_err(&wblock->dev.dev,
 868			"Buffer %lld too small, need at least %lld\n",
 869			buf->length, wblock->req_buf_size);
 870		ret = -EINVAL;
 871		goto out_ioctl;
 872	}
 873	/* if it's too big, warn, driver will only use what is needed */
 874	if (buf->length > wblock->req_buf_size)
 875		dev_warn(&wblock->dev.dev,
 876			"Buffer %lld is bigger than required %lld\n",
 877			buf->length, wblock->req_buf_size);
 878
 879	/* copy the structure from userspace */
 880	if (copy_from_user(buf, input, wblock->req_buf_size)) {
 881		dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
 882			wblock->req_buf_size);
 883		ret = -EFAULT;
 884		goto out_ioctl;
 885	}
 886
 887	/* let the driver do any filtering and do the call */
 888	wdriver = container_of(wblock->dev.dev.driver,
 889			       struct wmi_driver, driver);
 890	if (!try_module_get(wdriver->driver.owner)) {
 891		ret = -EBUSY;
 892		goto out_ioctl;
 893	}
 894	ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
 895	module_put(wdriver->driver.owner);
 896	if (ret)
 897		goto out_ioctl;
 898
 899	/* return the result (only up to our internal buffer size) */
 900	if (copy_to_user(input, buf, wblock->req_buf_size)) {
 901		dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
 902			wblock->req_buf_size);
 903		ret = -EFAULT;
 904	}
 905
 906out_ioctl:
 907	mutex_unlock(&wblock->char_mutex);
 908	return ret;
 909}
 910
 911static const struct file_operations wmi_fops = {
 912	.owner		= THIS_MODULE,
 913	.read		= wmi_char_read,
 914	.open		= wmi_char_open,
 915	.unlocked_ioctl	= wmi_ioctl,
 916	.compat_ioctl	= compat_ptr_ioctl,
 917};
 918
 919static int wmi_dev_probe(struct device *dev)
 920{
 921	struct wmi_block *wblock = dev_to_wblock(dev);
 922	struct wmi_driver *wdriver =
 923		container_of(dev->driver, struct wmi_driver, driver);
 924	int ret = 0;
 925	char *buf;
 926
 927	if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
 928		dev_warn(dev, "failed to enable device -- probing anyway\n");
 929
 930	if (wdriver->probe) {
 931		ret = wdriver->probe(dev_to_wdev(dev),
 932				find_guid_context(wblock, wdriver));
 933		if (ret != 0)
 934			goto probe_failure;
 935	}
 936
 937	/* driver wants a character device made */
 938	if (wdriver->filter_callback) {
 939		/* check that required buffer size declared by driver or MOF */
 940		if (!wblock->req_buf_size) {
 941			dev_err(&wblock->dev.dev,
 942				"Required buffer size not set\n");
 943			ret = -EINVAL;
 944			goto probe_failure;
 945		}
 946
 947		wblock->handler_data = kmalloc(wblock->req_buf_size,
 948					       GFP_KERNEL);
 949		if (!wblock->handler_data) {
 950			ret = -ENOMEM;
 951			goto probe_failure;
 952		}
 953
 954		buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
 955		if (!buf) {
 956			ret = -ENOMEM;
 957			goto probe_string_failure;
 958		}
 959		wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
 960		wblock->char_dev.name = buf;
 961		wblock->char_dev.fops = &wmi_fops;
 962		wblock->char_dev.mode = 0444;
 963		ret = misc_register(&wblock->char_dev);
 964		if (ret) {
 965			dev_warn(dev, "failed to register char dev: %d\n", ret);
 966			ret = -ENOMEM;
 967			goto probe_misc_failure;
 968		}
 969	}
 970
 971	return 0;
 972
 973probe_misc_failure:
 974	kfree(buf);
 975probe_string_failure:
 976	kfree(wblock->handler_data);
 977probe_failure:
 978	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
 979		dev_warn(dev, "failed to disable device\n");
 980	return ret;
 981}
 982
 983static int wmi_dev_remove(struct device *dev)
 984{
 985	struct wmi_block *wblock = dev_to_wblock(dev);
 986	struct wmi_driver *wdriver =
 987		container_of(dev->driver, struct wmi_driver, driver);
 988
 989	if (wdriver->filter_callback) {
 990		misc_deregister(&wblock->char_dev);
 991		kfree(wblock->char_dev.name);
 992		kfree(wblock->handler_data);
 993	}
 994
 995	if (wdriver->remove)
 996		wdriver->remove(dev_to_wdev(dev));
 997
 998	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
 999		dev_warn(dev, "failed to disable device\n");
1000
1001	return 0;
1002}
1003
1004static struct class wmi_bus_class = {
1005	.name = "wmi_bus",
1006};
1007
1008static struct bus_type wmi_bus_type = {
1009	.name = "wmi",
 
 
1010	.dev_groups = wmi_groups,
1011	.match = wmi_dev_match,
1012	.uevent = wmi_dev_uevent,
1013	.probe = wmi_dev_probe,
1014	.remove = wmi_dev_remove,
1015};
1016
1017static const struct device_type wmi_type_event = {
1018	.name = "event",
1019	.groups = wmi_event_groups,
1020	.release = wmi_dev_release,
1021};
1022
1023static const struct device_type wmi_type_method = {
1024	.name = "method",
1025	.groups = wmi_method_groups,
1026	.release = wmi_dev_release,
1027};
1028
1029static const struct device_type wmi_type_data = {
1030	.name = "data",
1031	.groups = wmi_data_groups,
1032	.release = wmi_dev_release,
1033};
1034
1035static int wmi_create_device(struct device *wmi_bus_dev,
1036			     const struct guid_block *gblock,
1037			     struct wmi_block *wblock,
1038			     struct acpi_device *device)
1039{
1040	struct acpi_device_info *info;
1041	char method[5];
1042	int result;
1043
1044	if (gblock->flags & ACPI_WMI_EVENT) {
1045		wblock->dev.dev.type = &wmi_type_event;
1046		goto out_init;
1047	}
1048
1049	if (gblock->flags & ACPI_WMI_METHOD) {
1050		wblock->dev.dev.type = &wmi_type_method;
1051		mutex_init(&wblock->char_mutex);
1052		goto out_init;
1053	}
1054
1055	/*
1056	 * Data Block Query Control Method (WQxx by convention) is
1057	 * required per the WMI documentation. If it is not present,
1058	 * we ignore this data block.
1059	 */
1060	strcpy(method, "WQ");
1061	strncat(method, wblock->gblock.object_id, 2);
1062	result = get_subobj_info(device->handle, method, &info);
1063
1064	if (result) {
1065		dev_warn(wmi_bus_dev,
1066			 "%s data block query control method not found\n",
1067			 method);
1068		return result;
1069	}
1070
1071	wblock->dev.dev.type = &wmi_type_data;
1072
1073	/*
1074	 * The Microsoft documentation specifically states:
1075	 *
1076	 *   Data blocks registered with only a single instance
1077	 *   can ignore the parameter.
1078	 *
1079	 * ACPICA will get mad at us if we call the method with the wrong number
1080	 * of arguments, so check what our method expects.  (On some Dell
1081	 * laptops, WQxx may not be a method at all.)
1082	 */
1083	if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1084		wblock->read_takes_no_args = true;
1085
1086	kfree(info);
1087
1088	strcpy(method, "WS");
1089	strncat(method, wblock->gblock.object_id, 2);
1090	result = get_subobj_info(device->handle, method, NULL);
1091
1092	if (result == 0)
1093		wblock->dev.setable = true;
1094
1095 out_init:
1096	wblock->dev.dev.bus = &wmi_bus_type;
1097	wblock->dev.dev.parent = wmi_bus_dev;
1098
1099	dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1100
1101	device_initialize(&wblock->dev.dev);
1102
1103	return 0;
1104}
1105
1106static void wmi_free_devices(struct acpi_device *device)
1107{
1108	struct wmi_block *wblock, *next;
1109
1110	/* Delete devices for all the GUIDs */
1111	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1112		if (wblock->acpi_device == device) {
1113			list_del(&wblock->list);
1114			device_unregister(&wblock->dev.dev);
1115		}
 
1116	}
1117}
1118
1119static bool guid_already_parsed(struct acpi_device *device, const u8 *guid)
1120{
1121	struct wmi_block *wblock;
1122
1123	list_for_each_entry(wblock, &wmi_block_list, list) {
1124		if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1125			/*
1126			 * Because we historically didn't track the relationship
1127			 * between GUIDs and ACPI nodes, we don't know whether
1128			 * we need to suppress GUIDs that are unique on a
1129			 * given node but duplicated across nodes.
1130			 */
1131			dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1132				 guid, dev_name(&wblock->acpi_device->dev));
1133			return true;
1134		}
1135	}
1136
1137	return false;
1138}
1139
1140/*
1141 * Parse the _WDG method for the GUID data blocks
1142 */
1143static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1144{
1145	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
 
1146	const struct guid_block *gblock;
1147	struct wmi_block *wblock, *next;
1148	union acpi_object *obj;
1149	acpi_status status;
1150	int retval = 0;
1151	u32 i, total;
1152
1153	status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1154	if (ACPI_FAILURE(status))
1155		return -ENXIO;
1156
1157	obj = (union acpi_object *) out.pointer;
1158	if (!obj)
1159		return -ENXIO;
1160
1161	if (obj->type != ACPI_TYPE_BUFFER) {
1162		retval = -ENXIO;
1163		goto out_free_pointer;
1164	}
1165
1166	gblock = (const struct guid_block *)obj->buffer.pointer;
1167	total = obj->buffer.length / sizeof(struct guid_block);
1168
1169	for (i = 0; i < total; i++) {
1170		if (debug_dump_wdg)
1171			wmi_dump_wdg(&gblock[i]);
1172
1173		/*
1174		 * Some WMI devices, like those for nVidia hooks, have a
1175		 * duplicate GUID. It's not clear what we should do in this
1176		 * case yet, so for now, we'll just ignore the duplicate
1177		 * for device creation.
1178		 */
1179		if (guid_already_parsed(device, gblock[i].guid))
1180			continue;
1181
1182		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1183		if (!wblock) {
1184			retval = -ENOMEM;
1185			break;
1186		}
1187
1188		wblock->acpi_device = device;
1189		wblock->gblock = gblock[i];
1190
1191		retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1192		if (retval) {
1193			kfree(wblock);
1194			continue;
 
 
 
 
 
 
 
 
1195		}
1196
1197		list_add_tail(&wblock->list, &wmi_block_list);
1198
1199		if (debug_event) {
1200			wblock->handler = wmi_notify_debug;
1201			wmi_method_enable(wblock, 1);
1202		}
1203	}
1204
1205	/*
1206	 * Now that all of the devices are created, add them to the
1207	 * device tree and probe subdrivers.
1208	 */
1209	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1210		if (wblock->acpi_device != device)
1211			continue;
1212
1213		retval = device_add(&wblock->dev.dev);
1214		if (retval) {
1215			dev_err(wmi_bus_dev, "failed to register %pUL\n",
1216				wblock->gblock.guid);
1217			if (debug_event)
1218				wmi_method_enable(wblock, 0);
1219			list_del(&wblock->list);
1220			put_device(&wblock->dev.dev);
1221		}
1222	}
1223
1224out_free_pointer:
1225	kfree(out.pointer);
 
1226	return retval;
1227}
1228
1229/*
1230 * WMI can have EmbeddedControl access regions. In which case, we just want to
1231 * hand these off to the EC driver.
1232 */
1233static acpi_status
1234acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1235		      u32 bits, u64 *value,
1236		      void *handler_context, void *region_context)
1237{
1238	int result = 0, i = 0;
1239	u8 temp = 0;
1240
1241	if ((address > 0xFF) || !value)
1242		return AE_BAD_PARAMETER;
1243
1244	if (function != ACPI_READ && function != ACPI_WRITE)
1245		return AE_BAD_PARAMETER;
1246
1247	if (bits != 8)
1248		return AE_BAD_PARAMETER;
1249
1250	if (function == ACPI_READ) {
1251		result = ec_read(address, &temp);
1252		(*value) |= ((u64)temp) << i;
1253	} else {
1254		temp = 0xff & ((*value) >> i);
1255		result = ec_write(address, temp);
1256	}
1257
1258	switch (result) {
1259	case -EINVAL:
1260		return AE_BAD_PARAMETER;
 
1261	case -ENODEV:
1262		return AE_NOT_FOUND;
 
1263	case -ETIME:
1264		return AE_TIME;
 
1265	default:
1266		return AE_OK;
1267	}
1268}
1269
1270static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1271				    void *context)
1272{
1273	struct guid_block *block;
1274	struct wmi_block *wblock;
1275	bool found_it = false;
1276
1277	list_for_each_entry(wblock, &wmi_block_list, list) {
 
1278		block = &wblock->gblock;
1279
1280		if (wblock->acpi_device->handle == handle &&
1281		    (block->flags & ACPI_WMI_EVENT) &&
1282		    (block->notify_id == event))
1283		{
1284			found_it = true;
 
 
 
 
 
 
 
1285			break;
1286		}
1287	}
1288
1289	if (!found_it)
1290		return;
1291
1292	/* If a driver is bound, then notify the driver. */
1293	if (wblock->dev.dev.driver) {
1294		struct wmi_driver *driver;
1295		struct acpi_object_list input;
1296		union acpi_object params[1];
1297		struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1298		acpi_status status;
1299
1300		driver = container_of(wblock->dev.dev.driver,
1301				      struct wmi_driver, driver);
1302
1303		input.count = 1;
1304		input.pointer = params;
1305		params[0].type = ACPI_TYPE_INTEGER;
1306		params[0].integer.value = event;
1307
1308		status = acpi_evaluate_object(wblock->acpi_device->handle,
1309					      "_WED", &input, &evdata);
1310		if (ACPI_FAILURE(status)) {
1311			dev_warn(&wblock->dev.dev,
1312				 "failed to get event data\n");
1313			return;
1314		}
1315
1316		if (driver->notify)
1317			driver->notify(&wblock->dev,
1318				       (union acpi_object *)evdata.pointer);
1319
1320		kfree(evdata.pointer);
1321	} else if (wblock->handler) {
1322		/* Legacy handler */
1323		wblock->handler(event, wblock->handler_data);
1324	}
1325
1326	if (debug_event)
1327		pr_info("DEBUG Event GUID: %pUL\n", wblock->gblock.guid);
1328
1329	acpi_bus_generate_netlink_event(
1330		wblock->acpi_device->pnp.device_class,
1331		dev_name(&wblock->dev.dev),
1332		event, 0);
1333
1334}
1335
1336static int acpi_wmi_remove(struct platform_device *device)
1337{
1338	struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1339
1340	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1341				   acpi_wmi_notify_handler);
1342	acpi_remove_address_space_handler(acpi_device->handle,
1343				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1344	wmi_free_devices(acpi_device);
1345	device_unregister((struct device *)dev_get_drvdata(&device->dev));
1346
1347	return 0;
1348}
1349
1350static int acpi_wmi_probe(struct platform_device *device)
1351{
1352	struct acpi_device *acpi_device;
1353	struct device *wmi_bus_dev;
1354	acpi_status status;
1355	int error;
1356
1357	acpi_device = ACPI_COMPANION(&device->dev);
1358	if (!acpi_device) {
1359		dev_err(&device->dev, "ACPI companion is missing\n");
1360		return -ENODEV;
1361	}
1362
1363	status = acpi_install_address_space_handler(acpi_device->handle,
1364						    ACPI_ADR_SPACE_EC,
1365						    &acpi_wmi_ec_space_handler,
1366						    NULL, NULL);
1367	if (ACPI_FAILURE(status)) {
1368		dev_err(&device->dev, "Error installing EC region handler\n");
1369		return -ENODEV;
1370	}
1371
1372	status = acpi_install_notify_handler(acpi_device->handle,
1373					     ACPI_DEVICE_NOTIFY,
1374					     acpi_wmi_notify_handler,
1375					     NULL);
1376	if (ACPI_FAILURE(status)) {
1377		dev_err(&device->dev, "Error installing notify handler\n");
1378		error = -ENODEV;
1379		goto err_remove_ec_handler;
1380	}
1381
1382	wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1383				    NULL, "wmi_bus-%s", dev_name(&device->dev));
1384	if (IS_ERR(wmi_bus_dev)) {
1385		error = PTR_ERR(wmi_bus_dev);
1386		goto err_remove_notify_handler;
1387	}
1388	dev_set_drvdata(&device->dev, wmi_bus_dev);
1389
1390	error = parse_wdg(wmi_bus_dev, acpi_device);
1391	if (error) {
 
 
 
1392		pr_err("Failed to parse WDG method\n");
1393		goto err_remove_busdev;
1394	}
1395
1396	return 0;
1397
1398err_remove_busdev:
1399	device_unregister(wmi_bus_dev);
1400
1401err_remove_notify_handler:
1402	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1403				   acpi_wmi_notify_handler);
1404
1405err_remove_ec_handler:
1406	acpi_remove_address_space_handler(acpi_device->handle,
1407					  ACPI_ADR_SPACE_EC,
1408					  &acpi_wmi_ec_space_handler);
1409
1410	return error;
1411}
1412
1413int __must_check __wmi_driver_register(struct wmi_driver *driver,
1414				       struct module *owner)
1415{
1416	driver->driver.owner = owner;
1417	driver->driver.bus = &wmi_bus_type;
1418
1419	return driver_register(&driver->driver);
1420}
1421EXPORT_SYMBOL(__wmi_driver_register);
1422
1423void wmi_driver_unregister(struct wmi_driver *driver)
1424{
1425	driver_unregister(&driver->driver);
1426}
1427EXPORT_SYMBOL(wmi_driver_unregister);
1428
1429static int __init acpi_wmi_init(void)
1430{
1431	int error;
1432
1433	if (acpi_disabled)
1434		return -ENODEV;
1435
1436	error = class_register(&wmi_bus_class);
1437	if (error)
1438		return error;
1439
1440	error = bus_register(&wmi_bus_type);
1441	if (error)
1442		goto err_unreg_class;
1443
1444	error = platform_driver_register(&acpi_wmi_driver);
1445	if (error) {
1446		pr_err("Error loading mapper\n");
1447		goto err_unreg_bus;
 
1448	}
1449
 
1450	return 0;
1451
1452err_unreg_bus:
1453	bus_unregister(&wmi_bus_type);
1454
1455err_unreg_class:
1456	class_unregister(&wmi_bus_class);
1457
1458	return error;
1459}
1460
1461static void __exit acpi_wmi_exit(void)
1462{
1463	platform_driver_unregister(&acpi_wmi_driver);
1464	bus_unregister(&wmi_bus_type);
1465	class_unregister(&wmi_bus_class);
 
1466}
1467
1468subsys_initcall_sync(acpi_wmi_init);
1469module_exit(acpi_wmi_exit);