Linux Audio

Check our new training course

Loading...
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);
v5.9
   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
  35ACPI_MODULE_NAME("wmi");
  36MODULE_AUTHOR("Carlos Corbacho");
  37MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
  38MODULE_LICENSE("GPL");
  39
 
 
  40static LIST_HEAD(wmi_block_list);
  41
  42struct guid_block {
  43	char guid[16];
  44	union {
  45		char object_id[2];
  46		struct {
  47			unsigned char notify_id;
  48			unsigned char reserved;
  49		};
  50	};
  51	u8 instance_count;
  52	u8 flags;
  53};
  54
  55struct wmi_block {
  56	struct wmi_device dev;
  57	struct list_head list;
  58	struct guid_block gblock;
  59	struct miscdevice char_dev;
  60	struct mutex char_mutex;
  61	struct acpi_device *acpi_device;
  62	wmi_notify_handler handler;
  63	void *handler_data;
  64	u64 req_buf_size;
  65
  66	bool read_takes_no_args;
  67};
  68
  69
  70/*
  71 * If the GUID data block is marked as expensive, we must enable and
  72 * explicitily disable data collection.
  73 */
  74#define ACPI_WMI_EXPENSIVE   0x1
  75#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
  76#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
  77#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
  78
  79static bool debug_event;
  80module_param(debug_event, bool, 0444);
  81MODULE_PARM_DESC(debug_event,
  82		 "Log WMI Events [0/1]");
  83
  84static bool debug_dump_wdg;
  85module_param(debug_dump_wdg, bool, 0444);
  86MODULE_PARM_DESC(debug_dump_wdg,
  87		 "Dump available WMI interfaces [0/1]");
  88
  89static int acpi_wmi_remove(struct platform_device *device);
  90static int acpi_wmi_probe(struct platform_device *device);
 
  91
  92static const struct acpi_device_id wmi_device_ids[] = {
  93	{"PNP0C14", 0},
  94	{"pnp0c14", 0},
  95	{"", 0},
  96};
  97MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
  98
  99static struct platform_driver acpi_wmi_driver = {
 100	.driver = {
 101		.name = "acpi-wmi",
 102		.acpi_match_table = wmi_device_ids,
 
 
 
 
 103	},
 104	.probe = acpi_wmi_probe,
 105	.remove = acpi_wmi_remove,
 106};
 107
 108/*
 109 * GUID parsing functions
 110 */
 111
 112static bool find_guid(const char *guid_string, struct wmi_block **out)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 113{
 114	guid_t guid_input;
 115	struct wmi_block *wblock;
 116	struct guid_block *block;
 
 117
 118	if (guid_parse(guid_string, &guid_input))
 119		return false;
 120
 121	list_for_each_entry(wblock, &wmi_block_list, list) {
 122		block = &wblock->gblock;
 123
 124		if (memcmp(block->guid, &guid_input, 16) == 0) {
 125			if (out)
 126				*out = wblock;
 127			return true;
 128		}
 129	}
 130	return false;
 131}
 132
 133static const void *find_guid_context(struct wmi_block *wblock,
 134				      struct wmi_driver *wdriver)
 
 
 
 
 
 
 
 
 
 135{
 136	const struct wmi_device_id *id;
 137	guid_t guid_input;
 138
 139	if (wblock == NULL || wdriver == NULL)
 140		return NULL;
 141	if (wdriver->id_table == NULL)
 142		return NULL;
 143
 144	id = wdriver->id_table;
 145	while (*id->guid_string) {
 146		if (guid_parse(id->guid_string, &guid_input))
 147			continue;
 148		if (!memcmp(wblock->gblock.guid, &guid_input, 16))
 149			return id->context;
 150		id++;
 151	}
 152	return NULL;
 
 153}
 154
 155static int get_subobj_info(acpi_handle handle, const char *pathname,
 156			   struct acpi_device_info **info)
 157{
 158	struct acpi_device_info *dummy_info, **info_ptr;
 159	acpi_handle subobj_handle;
 160	acpi_status status;
 
 161
 162	status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
 163	if (status == AE_NOT_FOUND)
 164		return -ENOENT;
 165	else if (ACPI_FAILURE(status))
 166		return -EIO;
 167
 168	info_ptr = info ? info : &dummy_info;
 169	status = acpi_get_object_info(subobj_handle, info_ptr);
 170	if (ACPI_FAILURE(status))
 171		return -EIO;
 172
 173	if (!info)
 174		kfree(dummy_info);
 175
 176	return 0;
 
 
 
 177}
 178
 179static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
 180{
 181	struct guid_block *block = NULL;
 182	char method[5];
 183	acpi_status status;
 184	acpi_handle handle;
 185
 186	block = &wblock->gblock;
 187	handle = wblock->acpi_device->handle;
 188
 189	snprintf(method, 5, "WE%02X", block->notify_id);
 190	status = acpi_execute_simple_method(handle, method, enable);
 191
 192	if (status != AE_OK && status != AE_NOT_FOUND)
 193		return status;
 194	else
 195		return AE_OK;
 196}
 197
 198/*
 199 * Exported WMI functions
 200 */
 201
 202/**
 203 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
 204 * @wdev: A wmi bus device from a driver
 205 * @length: Required buffer size
 206 *
 207 * Allocates memory needed for buffer, stores the buffer size in that memory
 208 */
 209int set_required_buffer_size(struct wmi_device *wdev, u64 length)
 210{
 211	struct wmi_block *wblock;
 212
 213	wblock = container_of(wdev, struct wmi_block, dev);
 214	wblock->req_buf_size = length;
 215
 216	return 0;
 217}
 218EXPORT_SYMBOL_GPL(set_required_buffer_size);
 219
 220/**
 221 * wmi_evaluate_method - Evaluate a WMI method
 222 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 223 * @instance: Instance index
 224 * @method_id: Method ID to call
 225 * @in: Buffer containing input for the method call
 226 * @out: Empty buffer to return the method results
 227 *
 228 * Call an ACPI-WMI method
 229 */
 230acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
 231u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 232{
 233	struct wmi_block *wblock = NULL;
 234
 235	if (!find_guid(guid_string, &wblock))
 236		return AE_ERROR;
 237	return wmidev_evaluate_method(&wblock->dev, instance, method_id,
 238				      in, out);
 239}
 240EXPORT_SYMBOL_GPL(wmi_evaluate_method);
 241
 242/**
 243 * wmidev_evaluate_method - Evaluate a WMI method
 244 * @wdev: A wmi bus device from a driver
 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 wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
 253	u32 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	wblock = container_of(wdev, struct wmi_block, dev);
 
 
 264	block = &wblock->gblock;
 265	handle = wblock->acpi_device->handle;
 266
 267	if (!(block->flags & ACPI_WMI_METHOD))
 268		return AE_BAD_DATA;
 269
 270	if (block->instance_count <= instance)
 271		return AE_BAD_PARAMETER;
 272
 273	input.count = 2;
 274	input.pointer = params;
 275	params[0].type = ACPI_TYPE_INTEGER;
 276	params[0].integer.value = instance;
 277	params[1].type = ACPI_TYPE_INTEGER;
 278	params[1].integer.value = method_id;
 279
 280	if (in) {
 281		input.count = 3;
 282
 283		if (block->flags & ACPI_WMI_STRING) {
 284			params[2].type = ACPI_TYPE_STRING;
 285		} else {
 286			params[2].type = ACPI_TYPE_BUFFER;
 287		}
 288		params[2].buffer.length = in->length;
 289		params[2].buffer.pointer = in->pointer;
 290	}
 291
 292	strncat(method, block->object_id, 2);
 293
 294	status = acpi_evaluate_object(handle, method, &input, out);
 295
 296	return status;
 297}
 298EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
 299
 300static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
 301				 struct acpi_buffer *out)
 
 
 
 
 
 
 
 
 302{
 303	struct guid_block *block = NULL;
 
 304	acpi_handle handle;
 305	acpi_status status, wc_status = AE_ERROR;
 306	struct acpi_object_list input;
 307	union acpi_object wq_params[1];
 308	char method[5];
 309	char wc_method[5] = "WC";
 310
 311	if (!out)
 312		return AE_BAD_PARAMETER;
 313
 
 
 
 314	block = &wblock->gblock;
 315	handle = wblock->acpi_device->handle;
 316
 317	if (block->instance_count <= instance)
 318		return AE_BAD_PARAMETER;
 319
 320	/* Check GUID is a data block */
 321	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 322		return AE_ERROR;
 323
 324	input.count = 1;
 325	input.pointer = wq_params;
 326	wq_params[0].type = ACPI_TYPE_INTEGER;
 327	wq_params[0].integer.value = instance;
 328
 329	if (instance == 0 && wblock->read_takes_no_args)
 330		input.count = 0;
 331
 332	/*
 333	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
 334	 * enable collection.
 335	 */
 336	if (block->flags & ACPI_WMI_EXPENSIVE) {
 337		strncat(wc_method, block->object_id, 2);
 338
 339		/*
 340		 * Some GUIDs break the specification by declaring themselves
 341		 * expensive, but have no corresponding WCxx method. So we
 342		 * should not fail if this happens.
 343		 */
 344		wc_status = acpi_execute_simple_method(handle, wc_method, 1);
 
 
 345	}
 346
 347	strcpy(method, "WQ");
 348	strncat(method, block->object_id, 2);
 349
 350	status = acpi_evaluate_object(handle, method, &input, out);
 351
 352	/*
 353	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
 354	 * the WQxx method failed - we should disable collection anyway.
 355	 */
 356	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
 357		status = acpi_execute_simple_method(handle, wc_method, 0);
 358	}
 359
 360	return status;
 361}
 362
 363/**
 364 * wmi_query_block - Return contents of a WMI block (deprecated)
 365 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 366 * @instance: Instance index
 367 * @out: Empty buffer to return the contents of the data block to
 368 *
 369 * Return the contents of an ACPI-WMI data block to a buffer
 370 */
 371acpi_status wmi_query_block(const char *guid_string, u8 instance,
 372			    struct acpi_buffer *out)
 373{
 374	struct wmi_block *wblock;
 375
 376	if (!guid_string)
 377		return AE_BAD_PARAMETER;
 378
 379	if (!find_guid(guid_string, &wblock))
 380		return AE_ERROR;
 381
 382	return __query_block(wblock, instance, out);
 383}
 384EXPORT_SYMBOL_GPL(wmi_query_block);
 385
 386union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
 387{
 388	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
 389	struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
 390
 391	if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
 392		return NULL;
 393
 394	return (union acpi_object *)out.pointer;
 395}
 396EXPORT_SYMBOL_GPL(wmidev_block_query);
 397
 398/**
 399 * wmi_set_block - Write to a WMI block
 400 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 401 * @instance: Instance index
 402 * @in: Buffer containing new values for the data block
 403 *
 404 * Write the contents of the input buffer to an ACPI-WMI data block
 405 */
 406acpi_status wmi_set_block(const char *guid_string, u8 instance,
 407			  const struct acpi_buffer *in)
 408{
 409	struct guid_block *block = NULL;
 410	struct wmi_block *wblock = NULL;
 411	acpi_handle handle;
 412	struct acpi_object_list input;
 413	union acpi_object params[2];
 414	char method[5] = "WS";
 415
 416	if (!guid_string || !in)
 417		return AE_BAD_DATA;
 418
 419	if (!find_guid(guid_string, &wblock))
 420		return AE_ERROR;
 421
 422	block = &wblock->gblock;
 423	handle = wblock->acpi_device->handle;
 424
 425	if (block->instance_count <= instance)
 426		return AE_BAD_PARAMETER;
 427
 428	/* Check GUID is a data block */
 429	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 430		return AE_ERROR;
 431
 432	input.count = 2;
 433	input.pointer = params;
 434	params[0].type = ACPI_TYPE_INTEGER;
 435	params[0].integer.value = instance;
 436
 437	if (block->flags & ACPI_WMI_STRING) {
 438		params[1].type = ACPI_TYPE_STRING;
 439	} else {
 440		params[1].type = ACPI_TYPE_BUFFER;
 441	}
 442	params[1].buffer.length = in->length;
 443	params[1].buffer.pointer = in->pointer;
 444
 445	strncat(method, block->object_id, 2);
 446
 447	return acpi_evaluate_object(handle, method, &input, NULL);
 448}
 449EXPORT_SYMBOL_GPL(wmi_set_block);
 450
 451static void wmi_dump_wdg(const struct guid_block *g)
 452{
 453	pr_info("%pUL:\n", g->guid);
 454	if (g->flags & ACPI_WMI_EVENT)
 455		pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
 456	else
 457		pr_info("\tobject_id: %2pE\n", g->object_id);
 458	pr_info("\tinstance_count: %d\n", g->instance_count);
 459	pr_info("\tflags: %#x", g->flags);
 460	if (g->flags) {
 461		if (g->flags & ACPI_WMI_EXPENSIVE)
 462			pr_cont(" ACPI_WMI_EXPENSIVE");
 463		if (g->flags & ACPI_WMI_METHOD)
 464			pr_cont(" ACPI_WMI_METHOD");
 465		if (g->flags & ACPI_WMI_STRING)
 466			pr_cont(" ACPI_WMI_STRING");
 467		if (g->flags & ACPI_WMI_EVENT)
 468			pr_cont(" ACPI_WMI_EVENT");
 469	}
 470	pr_cont("\n");
 471
 472}
 473
 474static void wmi_notify_debug(u32 value, void *context)
 475{
 476	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
 477	union acpi_object *obj;
 478	acpi_status status;
 479
 480	status = wmi_get_event_data(value, &response);
 481	if (status != AE_OK) {
 482		pr_info("bad event status 0x%x\n", status);
 483		return;
 484	}
 485
 486	obj = (union acpi_object *)response.pointer;
 487
 488	if (!obj)
 489		return;
 490
 491	pr_info("DEBUG Event ");
 492	switch(obj->type) {
 493	case ACPI_TYPE_BUFFER:
 494		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
 495		break;
 496	case ACPI_TYPE_STRING:
 497		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
 498		break;
 499	case ACPI_TYPE_INTEGER:
 500		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
 501		break;
 502	case ACPI_TYPE_PACKAGE:
 503		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
 504		break;
 505	default:
 506		pr_cont("object type 0x%X\n", obj->type);
 507	}
 508	kfree(obj);
 509}
 510
 511/**
 512 * wmi_install_notify_handler - Register handler for WMI events
 513 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 514 * @handler: Function to handle notifications
 515 * @data: Data to be returned to handler when event is fired
 516 *
 517 * Register a handler for events sent to the ACPI-WMI mapper device.
 518 */
 519acpi_status wmi_install_notify_handler(const char *guid,
 520wmi_notify_handler handler, void *data)
 521{
 522	struct wmi_block *block;
 523	acpi_status status = AE_NOT_EXIST;
 524	guid_t guid_input;
 
 525
 526	if (!guid || !handler)
 527		return AE_BAD_PARAMETER;
 528
 529	if (guid_parse(guid, &guid_input))
 530		return AE_BAD_PARAMETER;
 531
 532	list_for_each_entry(block, &wmi_block_list, list) {
 533		acpi_status wmi_status;
 
 534
 535		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 536			if (block->handler &&
 537			    block->handler != wmi_notify_debug)
 538				return AE_ALREADY_ACQUIRED;
 539
 540			block->handler = handler;
 541			block->handler_data = data;
 542
 543			wmi_status = wmi_method_enable(block, 1);
 544			if ((wmi_status != AE_OK) ||
 545			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
 546				status = wmi_status;
 547		}
 548	}
 549
 550	return status;
 551}
 552EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
 553
 554/**
 555 * wmi_uninstall_notify_handler - Unregister handler for WMI events
 556 * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 557 *
 558 * Unregister handler for events sent to the ACPI-WMI mapper device.
 559 */
 560acpi_status wmi_remove_notify_handler(const char *guid)
 561{
 562	struct wmi_block *block;
 563	acpi_status status = AE_NOT_EXIST;
 564	guid_t guid_input;
 
 565
 566	if (!guid)
 567		return AE_BAD_PARAMETER;
 568
 569	if (guid_parse(guid, &guid_input))
 570		return AE_BAD_PARAMETER;
 571
 572	list_for_each_entry(block, &wmi_block_list, list) {
 573		acpi_status wmi_status;
 
 574
 575		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 576			if (!block->handler ||
 577			    block->handler == wmi_notify_debug)
 578				return AE_NULL_ENTRY;
 579
 580			if (debug_event) {
 581				block->handler = wmi_notify_debug;
 582				status = AE_OK;
 583			} else {
 584				wmi_status = wmi_method_enable(block, 0);
 585				block->handler = NULL;
 586				block->handler_data = NULL;
 587				if ((wmi_status != AE_OK) ||
 588				    ((wmi_status == AE_OK) &&
 589				     (status == AE_NOT_EXIST)))
 590					status = wmi_status;
 591			}
 592		}
 593	}
 594
 595	return status;
 596}
 597EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
 598
 599/**
 600 * wmi_get_event_data - Get WMI data associated with an event
 601 *
 602 * @event: Event to find
 603 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
 604 *
 605 * Returns extra data associated with an event in WMI.
 606 */
 607acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
 608{
 609	struct acpi_object_list input;
 610	union acpi_object params[1];
 611	struct guid_block *gblock;
 612	struct wmi_block *wblock;
 
 613
 614	input.count = 1;
 615	input.pointer = params;
 616	params[0].type = ACPI_TYPE_INTEGER;
 617	params[0].integer.value = event;
 618
 619	list_for_each_entry(wblock, &wmi_block_list, list) {
 
 620		gblock = &wblock->gblock;
 621
 622		if ((gblock->flags & ACPI_WMI_EVENT) &&
 623			(gblock->notify_id == event))
 624			return acpi_evaluate_object(wblock->acpi_device->handle,
 625				"_WED", &input, out);
 626	}
 627
 628	return AE_NOT_FOUND;
 629}
 630EXPORT_SYMBOL_GPL(wmi_get_event_data);
 631
 632/**
 633 * wmi_has_guid - Check if a GUID is available
 634 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 635 *
 636 * Check if a given GUID is defined by _WDG
 637 */
 638bool wmi_has_guid(const char *guid_string)
 639{
 640	return find_guid(guid_string, NULL);
 641}
 642EXPORT_SYMBOL_GPL(wmi_has_guid);
 643
 644/**
 645 * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID
 646 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 647 *
 648 * Find the _UID of ACPI device associated with this WMI GUID.
 649 *
 650 * Return: The ACPI _UID field value or NULL if the WMI GUID was not found
 651 */
 652char *wmi_get_acpi_device_uid(const char *guid_string)
 653{
 654	struct wmi_block *wblock = NULL;
 655
 656	if (!find_guid(guid_string, &wblock))
 657		return NULL;
 658
 659	return acpi_device_uid(wblock->acpi_device);
 660}
 661EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
 662
 663static struct wmi_block *dev_to_wblock(struct device *dev)
 664{
 665	return container_of(dev, struct wmi_block, dev.dev);
 666}
 667
 668static struct wmi_device *dev_to_wdev(struct device *dev)
 669{
 670	return container_of(dev, struct wmi_device, dev);
 671}
 672
 673/*
 674 * sysfs interface
 675 */
 676static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 677			     char *buf)
 678{
 679	struct wmi_block *wblock = dev_to_wblock(dev);
 
 
 
 
 
 
 680
 681	return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
 682}
 683static DEVICE_ATTR_RO(modalias);
 684
 685static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
 686			 char *buf)
 687{
 688	struct wmi_block *wblock = dev_to_wblock(dev);
 689
 690	return sprintf(buf, "%pUL\n", wblock->gblock.guid);
 691}
 692static DEVICE_ATTR_RO(guid);
 693
 694static ssize_t instance_count_show(struct device *dev,
 695				   struct device_attribute *attr, char *buf)
 696{
 697	struct wmi_block *wblock = dev_to_wblock(dev);
 698
 699	return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
 700}
 701static DEVICE_ATTR_RO(instance_count);
 702
 703static ssize_t expensive_show(struct device *dev,
 704			      struct device_attribute *attr, char *buf)
 705{
 706	struct wmi_block *wblock = dev_to_wblock(dev);
 707
 708	return sprintf(buf, "%d\n",
 709		       (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
 710}
 711static DEVICE_ATTR_RO(expensive);
 712
 713static struct attribute *wmi_attrs[] = {
 714	&dev_attr_modalias.attr,
 715	&dev_attr_guid.attr,
 716	&dev_attr_instance_count.attr,
 717	&dev_attr_expensive.attr,
 718	NULL,
 719};
 720ATTRIBUTE_GROUPS(wmi);
 721
 722static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
 723			      char *buf)
 724{
 725	struct wmi_block *wblock = dev_to_wblock(dev);
 726
 727	return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
 728}
 729static DEVICE_ATTR_RO(notify_id);
 730
 731static struct attribute *wmi_event_attrs[] = {
 732	&dev_attr_notify_id.attr,
 733	NULL,
 734};
 735ATTRIBUTE_GROUPS(wmi_event);
 736
 737static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
 738			      char *buf)
 739{
 740	struct wmi_block *wblock = dev_to_wblock(dev);
 741
 742	return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
 743		       wblock->gblock.object_id[1]);
 744}
 745static DEVICE_ATTR_RO(object_id);
 746
 747static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
 748			    char *buf)
 749{
 750	struct wmi_device *wdev = dev_to_wdev(dev);
 751
 752	return sprintf(buf, "%d\n", (int)wdev->setable);
 753}
 754static DEVICE_ATTR_RO(setable);
 755
 756static struct attribute *wmi_data_attrs[] = {
 757	&dev_attr_object_id.attr,
 758	&dev_attr_setable.attr,
 759	NULL,
 760};
 761ATTRIBUTE_GROUPS(wmi_data);
 762
 763static struct attribute *wmi_method_attrs[] = {
 764	&dev_attr_object_id.attr,
 765	NULL,
 766};
 767ATTRIBUTE_GROUPS(wmi_method);
 768
 769static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 770{
 771	struct wmi_block *wblock = dev_to_wblock(dev);
 772
 773	if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
 774		return -ENOMEM;
 775
 776	if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
 
 777		return -ENOMEM;
 778
 779	return 0;
 780}
 781
 782static void wmi_dev_release(struct device *dev)
 783{
 784	struct wmi_block *wblock = dev_to_wblock(dev);
 785
 786	kfree(wblock);
 787}
 788
 789static int wmi_dev_match(struct device *dev, struct device_driver *driver)
 790{
 791	struct wmi_driver *wmi_driver =
 792		container_of(driver, struct wmi_driver, driver);
 793	struct wmi_block *wblock = dev_to_wblock(dev);
 794	const struct wmi_device_id *id = wmi_driver->id_table;
 795
 796	if (id == NULL)
 797		return 0;
 798
 799	while (*id->guid_string) {
 800		guid_t driver_guid;
 801
 802		if (WARN_ON(guid_parse(id->guid_string, &driver_guid)))
 803			continue;
 804		if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
 805			return 1;
 806
 807		id++;
 808	}
 809
 810	return 0;
 811}
 812static int wmi_char_open(struct inode *inode, struct file *filp)
 813{
 814	const char *driver_name = filp->f_path.dentry->d_iname;
 815	struct wmi_block *wblock = NULL;
 816	struct wmi_block *next = NULL;
 817
 818	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
 819		if (!wblock->dev.dev.driver)
 820			continue;
 821		if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
 822			filp->private_data = wblock;
 823			break;
 824		}
 825	}
 826
 827	if (!filp->private_data)
 828		return -ENODEV;
 829
 830	return nonseekable_open(inode, filp);
 831}
 832
 833static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
 834	size_t length, loff_t *offset)
 835{
 836	struct wmi_block *wblock = filp->private_data;
 837
 838	return simple_read_from_buffer(buffer, length, offset,
 839				       &wblock->req_buf_size,
 840				       sizeof(wblock->req_buf_size));
 841}
 842
 843static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 844{
 845	struct wmi_ioctl_buffer __user *input =
 846		(struct wmi_ioctl_buffer __user *) arg;
 847	struct wmi_block *wblock = filp->private_data;
 848	struct wmi_ioctl_buffer *buf = NULL;
 849	struct wmi_driver *wdriver = NULL;
 850	int ret;
 851
 852	if (_IOC_TYPE(cmd) != WMI_IOC)
 853		return -ENOTTY;
 854
 855	/* make sure we're not calling a higher instance than exists*/
 856	if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
 857		return -EINVAL;
 858
 859	mutex_lock(&wblock->char_mutex);
 860	buf = wblock->handler_data;
 861	if (get_user(buf->length, &input->length)) {
 862		dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
 863		ret = -EFAULT;
 864		goto out_ioctl;
 865	}
 866	/* if it's too small, abort */
 867	if (buf->length < wblock->req_buf_size) {
 868		dev_err(&wblock->dev.dev,
 869			"Buffer %lld too small, need at least %lld\n",
 870			buf->length, wblock->req_buf_size);
 871		ret = -EINVAL;
 872		goto out_ioctl;
 873	}
 874	/* if it's too big, warn, driver will only use what is needed */
 875	if (buf->length > wblock->req_buf_size)
 876		dev_warn(&wblock->dev.dev,
 877			"Buffer %lld is bigger than required %lld\n",
 878			buf->length, wblock->req_buf_size);
 879
 880	/* copy the structure from userspace */
 881	if (copy_from_user(buf, input, wblock->req_buf_size)) {
 882		dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
 883			wblock->req_buf_size);
 884		ret = -EFAULT;
 885		goto out_ioctl;
 886	}
 887
 888	/* let the driver do any filtering and do the call */
 889	wdriver = container_of(wblock->dev.dev.driver,
 890			       struct wmi_driver, driver);
 891	if (!try_module_get(wdriver->driver.owner)) {
 892		ret = -EBUSY;
 893		goto out_ioctl;
 894	}
 895	ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
 896	module_put(wdriver->driver.owner);
 897	if (ret)
 898		goto out_ioctl;
 899
 900	/* return the result (only up to our internal buffer size) */
 901	if (copy_to_user(input, buf, wblock->req_buf_size)) {
 902		dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
 903			wblock->req_buf_size);
 904		ret = -EFAULT;
 905	}
 906
 907out_ioctl:
 908	mutex_unlock(&wblock->char_mutex);
 909	return ret;
 910}
 911
 912static const struct file_operations wmi_fops = {
 913	.owner		= THIS_MODULE,
 914	.read		= wmi_char_read,
 915	.open		= wmi_char_open,
 916	.unlocked_ioctl	= wmi_ioctl,
 917	.compat_ioctl	= compat_ptr_ioctl,
 918};
 919
 920static int wmi_dev_probe(struct device *dev)
 921{
 922	struct wmi_block *wblock = dev_to_wblock(dev);
 923	struct wmi_driver *wdriver =
 924		container_of(dev->driver, struct wmi_driver, driver);
 925	int ret = 0;
 926	char *buf;
 927
 928	if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
 929		dev_warn(dev, "failed to enable device -- probing anyway\n");
 930
 931	if (wdriver->probe) {
 932		ret = wdriver->probe(dev_to_wdev(dev),
 933				find_guid_context(wblock, wdriver));
 934		if (ret != 0)
 935			goto probe_failure;
 936	}
 937
 938	/* driver wants a character device made */
 939	if (wdriver->filter_callback) {
 940		/* check that required buffer size declared by driver or MOF */
 941		if (!wblock->req_buf_size) {
 942			dev_err(&wblock->dev.dev,
 943				"Required buffer size not set\n");
 944			ret = -EINVAL;
 945			goto probe_failure;
 946		}
 947
 948		wblock->handler_data = kmalloc(wblock->req_buf_size,
 949					       GFP_KERNEL);
 950		if (!wblock->handler_data) {
 951			ret = -ENOMEM;
 952			goto probe_failure;
 953		}
 954
 955		buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
 956		if (!buf) {
 957			ret = -ENOMEM;
 958			goto probe_string_failure;
 959		}
 960		wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
 961		wblock->char_dev.name = buf;
 962		wblock->char_dev.fops = &wmi_fops;
 963		wblock->char_dev.mode = 0444;
 964		ret = misc_register(&wblock->char_dev);
 965		if (ret) {
 966			dev_warn(dev, "failed to register char dev: %d\n", ret);
 967			ret = -ENOMEM;
 968			goto probe_misc_failure;
 969		}
 970	}
 971
 972	return 0;
 973
 974probe_misc_failure:
 975	kfree(buf);
 976probe_string_failure:
 977	kfree(wblock->handler_data);
 978probe_failure:
 979	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
 980		dev_warn(dev, "failed to disable device\n");
 981	return ret;
 982}
 983
 984static int wmi_dev_remove(struct device *dev)
 985{
 986	struct wmi_block *wblock = dev_to_wblock(dev);
 987	struct wmi_driver *wdriver =
 988		container_of(dev->driver, struct wmi_driver, driver);
 989	int ret = 0;
 990
 991	if (wdriver->filter_callback) {
 992		misc_deregister(&wblock->char_dev);
 993		kfree(wblock->char_dev.name);
 994		kfree(wblock->handler_data);
 995	}
 996
 997	if (wdriver->remove)
 998		ret = wdriver->remove(dev_to_wdev(dev));
 999
1000	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
1001		dev_warn(dev, "failed to disable device\n");
1002
1003	return ret;
1004}
1005
1006static struct class wmi_bus_class = {
1007	.name = "wmi_bus",
1008};
1009
1010static struct bus_type wmi_bus_type = {
1011	.name = "wmi",
 
 
1012	.dev_groups = wmi_groups,
1013	.match = wmi_dev_match,
1014	.uevent = wmi_dev_uevent,
1015	.probe = wmi_dev_probe,
1016	.remove = wmi_dev_remove,
1017};
1018
1019static const struct device_type wmi_type_event = {
1020	.name = "event",
1021	.groups = wmi_event_groups,
1022	.release = wmi_dev_release,
1023};
1024
1025static const struct device_type wmi_type_method = {
1026	.name = "method",
1027	.groups = wmi_method_groups,
1028	.release = wmi_dev_release,
1029};
1030
1031static const struct device_type wmi_type_data = {
1032	.name = "data",
1033	.groups = wmi_data_groups,
1034	.release = wmi_dev_release,
1035};
1036
1037static int wmi_create_device(struct device *wmi_bus_dev,
1038			     const struct guid_block *gblock,
1039			     struct wmi_block *wblock,
1040			     struct acpi_device *device)
1041{
1042	struct acpi_device_info *info;
1043	char method[5];
1044	int result;
1045
1046	if (gblock->flags & ACPI_WMI_EVENT) {
1047		wblock->dev.dev.type = &wmi_type_event;
1048		goto out_init;
1049	}
1050
1051	if (gblock->flags & ACPI_WMI_METHOD) {
1052		wblock->dev.dev.type = &wmi_type_method;
1053		mutex_init(&wblock->char_mutex);
1054		goto out_init;
1055	}
1056
1057	/*
1058	 * Data Block Query Control Method (WQxx by convention) is
1059	 * required per the WMI documentation. If it is not present,
1060	 * we ignore this data block.
1061	 */
1062	strcpy(method, "WQ");
1063	strncat(method, wblock->gblock.object_id, 2);
1064	result = get_subobj_info(device->handle, method, &info);
1065
1066	if (result) {
1067		dev_warn(wmi_bus_dev,
1068			 "%s data block query control method not found\n",
1069			 method);
1070		return result;
1071	}
1072
1073	wblock->dev.dev.type = &wmi_type_data;
1074
1075	/*
1076	 * The Microsoft documentation specifically states:
1077	 *
1078	 *   Data blocks registered with only a single instance
1079	 *   can ignore the parameter.
1080	 *
1081	 * ACPICA will get mad at us if we call the method with the wrong number
1082	 * of arguments, so check what our method expects.  (On some Dell
1083	 * laptops, WQxx may not be a method at all.)
1084	 */
1085	if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1086		wblock->read_takes_no_args = true;
1087
1088	kfree(info);
1089
1090	strcpy(method, "WS");
1091	strncat(method, wblock->gblock.object_id, 2);
1092	result = get_subobj_info(device->handle, method, NULL);
1093
1094	if (result == 0)
1095		wblock->dev.setable = true;
1096
1097 out_init:
1098	wblock->dev.dev.bus = &wmi_bus_type;
1099	wblock->dev.dev.parent = wmi_bus_dev;
1100
1101	dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1102
1103	device_initialize(&wblock->dev.dev);
1104
1105	return 0;
1106}
1107
1108static void wmi_free_devices(struct acpi_device *device)
1109{
1110	struct wmi_block *wblock, *next;
1111
1112	/* Delete devices for all the GUIDs */
1113	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1114		if (wblock->acpi_device == device) {
1115			list_del(&wblock->list);
1116			device_unregister(&wblock->dev.dev);
1117		}
 
1118	}
1119}
1120
1121static bool guid_already_parsed(struct acpi_device *device, const u8 *guid)
1122{
1123	struct wmi_block *wblock;
1124
1125	list_for_each_entry(wblock, &wmi_block_list, list) {
1126		if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1127			/*
1128			 * Because we historically didn't track the relationship
1129			 * between GUIDs and ACPI nodes, we don't know whether
1130			 * we need to suppress GUIDs that are unique on a
1131			 * given node but duplicated across nodes.
1132			 */
1133			dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1134				 guid, dev_name(&wblock->acpi_device->dev));
1135			return true;
1136		}
1137	}
1138
1139	return false;
1140}
1141
1142/*
1143 * Parse the _WDG method for the GUID data blocks
1144 */
1145static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1146{
1147	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
 
1148	const struct guid_block *gblock;
1149	struct wmi_block *wblock, *next;
1150	union acpi_object *obj;
1151	acpi_status status;
1152	int retval = 0;
1153	u32 i, total;
1154
1155	status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1156	if (ACPI_FAILURE(status))
1157		return -ENXIO;
1158
1159	obj = (union acpi_object *) out.pointer;
1160	if (!obj)
1161		return -ENXIO;
1162
1163	if (obj->type != ACPI_TYPE_BUFFER) {
1164		retval = -ENXIO;
1165		goto out_free_pointer;
1166	}
1167
1168	gblock = (const struct guid_block *)obj->buffer.pointer;
1169	total = obj->buffer.length / sizeof(struct guid_block);
1170
1171	for (i = 0; i < total; i++) {
1172		if (debug_dump_wdg)
1173			wmi_dump_wdg(&gblock[i]);
1174
1175		/*
1176		 * Some WMI devices, like those for nVidia hooks, have a
1177		 * duplicate GUID. It's not clear what we should do in this
1178		 * case yet, so for now, we'll just ignore the duplicate
1179		 * for device creation.
1180		 */
1181		if (guid_already_parsed(device, gblock[i].guid))
1182			continue;
1183
1184		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1185		if (!wblock) {
1186			retval = -ENOMEM;
1187			break;
1188		}
1189
1190		wblock->acpi_device = device;
1191		wblock->gblock = gblock[i];
1192
1193		retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1194		if (retval) {
1195			kfree(wblock);
1196			continue;
 
 
 
 
 
 
 
 
1197		}
1198
1199		list_add_tail(&wblock->list, &wmi_block_list);
1200
1201		if (debug_event) {
1202			wblock->handler = wmi_notify_debug;
1203			wmi_method_enable(wblock, 1);
1204		}
1205	}
1206
1207	/*
1208	 * Now that all of the devices are created, add them to the
1209	 * device tree and probe subdrivers.
1210	 */
1211	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1212		if (wblock->acpi_device != device)
1213			continue;
1214
1215		retval = device_add(&wblock->dev.dev);
1216		if (retval) {
1217			dev_err(wmi_bus_dev, "failed to register %pUL\n",
1218				wblock->gblock.guid);
1219			if (debug_event)
1220				wmi_method_enable(wblock, 0);
1221			list_del(&wblock->list);
1222			put_device(&wblock->dev.dev);
1223		}
1224	}
1225
1226out_free_pointer:
1227	kfree(out.pointer);
 
1228	return retval;
1229}
1230
1231/*
1232 * WMI can have EmbeddedControl access regions. In which case, we just want to
1233 * hand these off to the EC driver.
1234 */
1235static acpi_status
1236acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1237		      u32 bits, u64 *value,
1238		      void *handler_context, void *region_context)
1239{
1240	int result = 0, i = 0;
1241	u8 temp = 0;
1242
1243	if ((address > 0xFF) || !value)
1244		return AE_BAD_PARAMETER;
1245
1246	if (function != ACPI_READ && function != ACPI_WRITE)
1247		return AE_BAD_PARAMETER;
1248
1249	if (bits != 8)
1250		return AE_BAD_PARAMETER;
1251
1252	if (function == ACPI_READ) {
1253		result = ec_read(address, &temp);
1254		(*value) |= ((u64)temp) << i;
1255	} else {
1256		temp = 0xff & ((*value) >> i);
1257		result = ec_write(address, temp);
1258	}
1259
1260	switch (result) {
1261	case -EINVAL:
1262		return AE_BAD_PARAMETER;
1263		break;
1264	case -ENODEV:
1265		return AE_NOT_FOUND;
1266		break;
1267	case -ETIME:
1268		return AE_TIME;
1269		break;
1270	default:
1271		return AE_OK;
1272	}
1273}
1274
1275static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1276				    void *context)
1277{
1278	struct guid_block *block;
1279	struct wmi_block *wblock;
1280	bool found_it = false;
1281
1282	list_for_each_entry(wblock, &wmi_block_list, list) {
 
1283		block = &wblock->gblock;
1284
1285		if (wblock->acpi_device->handle == handle &&
1286		    (block->flags & ACPI_WMI_EVENT) &&
1287		    (block->notify_id == event))
1288		{
1289			found_it = true;
 
 
 
 
 
 
 
1290			break;
1291		}
1292	}
1293
1294	if (!found_it)
1295		return;
1296
1297	/* If a driver is bound, then notify the driver. */
1298	if (wblock->dev.dev.driver) {
1299		struct wmi_driver *driver;
1300		struct acpi_object_list input;
1301		union acpi_object params[1];
1302		struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1303		acpi_status status;
1304
1305		driver = container_of(wblock->dev.dev.driver,
1306				      struct wmi_driver, driver);
1307
1308		input.count = 1;
1309		input.pointer = params;
1310		params[0].type = ACPI_TYPE_INTEGER;
1311		params[0].integer.value = event;
1312
1313		status = acpi_evaluate_object(wblock->acpi_device->handle,
1314					      "_WED", &input, &evdata);
1315		if (ACPI_FAILURE(status)) {
1316			dev_warn(&wblock->dev.dev,
1317				 "failed to get event data\n");
1318			return;
1319		}
1320
1321		if (driver->notify)
1322			driver->notify(&wblock->dev,
1323				       (union acpi_object *)evdata.pointer);
1324
1325		kfree(evdata.pointer);
1326	} else if (wblock->handler) {
1327		/* Legacy handler */
1328		wblock->handler(event, wblock->handler_data);
1329	}
1330
1331	if (debug_event)
1332		pr_info("DEBUG Event GUID: %pUL\n", wblock->gblock.guid);
1333
1334	acpi_bus_generate_netlink_event(
1335		wblock->acpi_device->pnp.device_class,
1336		dev_name(&wblock->dev.dev),
1337		event, 0);
1338
1339}
1340
1341static int acpi_wmi_remove(struct platform_device *device)
1342{
1343	struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1344
1345	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1346				   acpi_wmi_notify_handler);
1347	acpi_remove_address_space_handler(acpi_device->handle,
1348				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1349	wmi_free_devices(acpi_device);
1350	device_destroy(&wmi_bus_class, MKDEV(0, 0));
1351
1352	return 0;
1353}
1354
1355static int acpi_wmi_probe(struct platform_device *device)
1356{
1357	struct acpi_device *acpi_device;
1358	struct device *wmi_bus_dev;
1359	acpi_status status;
1360	int error;
1361
1362	acpi_device = ACPI_COMPANION(&device->dev);
1363	if (!acpi_device) {
1364		dev_err(&device->dev, "ACPI companion is missing\n");
1365		return -ENODEV;
1366	}
1367
1368	status = acpi_install_address_space_handler(acpi_device->handle,
1369						    ACPI_ADR_SPACE_EC,
1370						    &acpi_wmi_ec_space_handler,
1371						    NULL, NULL);
1372	if (ACPI_FAILURE(status)) {
1373		dev_err(&device->dev, "Error installing EC region handler\n");
1374		return -ENODEV;
1375	}
1376
1377	status = acpi_install_notify_handler(acpi_device->handle,
1378					     ACPI_DEVICE_NOTIFY,
1379					     acpi_wmi_notify_handler,
1380					     NULL);
1381	if (ACPI_FAILURE(status)) {
1382		dev_err(&device->dev, "Error installing notify handler\n");
1383		error = -ENODEV;
1384		goto err_remove_ec_handler;
1385	}
1386
1387	wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1388				    NULL, "wmi_bus-%s", dev_name(&device->dev));
1389	if (IS_ERR(wmi_bus_dev)) {
1390		error = PTR_ERR(wmi_bus_dev);
1391		goto err_remove_notify_handler;
1392	}
1393	dev_set_drvdata(&device->dev, wmi_bus_dev);
1394
1395	error = parse_wdg(wmi_bus_dev, acpi_device);
1396	if (error) {
 
 
 
1397		pr_err("Failed to parse WDG method\n");
1398		goto err_remove_busdev;
1399	}
1400
1401	return 0;
1402
1403err_remove_busdev:
1404	device_destroy(&wmi_bus_class, MKDEV(0, 0));
1405
1406err_remove_notify_handler:
1407	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1408				   acpi_wmi_notify_handler);
1409
1410err_remove_ec_handler:
1411	acpi_remove_address_space_handler(acpi_device->handle,
1412					  ACPI_ADR_SPACE_EC,
1413					  &acpi_wmi_ec_space_handler);
1414
1415	return error;
1416}
1417
1418int __must_check __wmi_driver_register(struct wmi_driver *driver,
1419				       struct module *owner)
1420{
1421	driver->driver.owner = owner;
1422	driver->driver.bus = &wmi_bus_type;
1423
1424	return driver_register(&driver->driver);
1425}
1426EXPORT_SYMBOL(__wmi_driver_register);
1427
1428void wmi_driver_unregister(struct wmi_driver *driver)
1429{
1430	driver_unregister(&driver->driver);
1431}
1432EXPORT_SYMBOL(wmi_driver_unregister);
1433
1434static int __init acpi_wmi_init(void)
1435{
1436	int error;
1437
1438	if (acpi_disabled)
1439		return -ENODEV;
1440
1441	error = class_register(&wmi_bus_class);
1442	if (error)
1443		return error;
1444
1445	error = bus_register(&wmi_bus_type);
1446	if (error)
1447		goto err_unreg_class;
1448
1449	error = platform_driver_register(&acpi_wmi_driver);
1450	if (error) {
1451		pr_err("Error loading mapper\n");
1452		goto err_unreg_bus;
 
1453	}
1454
 
1455	return 0;
1456
1457err_unreg_bus:
1458	bus_unregister(&wmi_bus_type);
1459
1460err_unreg_class:
1461	class_unregister(&wmi_bus_class);
1462
1463	return error;
1464}
1465
1466static void __exit acpi_wmi_exit(void)
1467{
1468	platform_driver_unregister(&acpi_wmi_driver);
1469	bus_unregister(&wmi_bus_type);
1470	class_unregister(&wmi_bus_class);
 
1471}
1472
1473subsys_initcall_sync(acpi_wmi_init);
1474module_exit(acpi_wmi_exit);