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v3.1
  1/*
  2 *  ACPI-WMI mapping driver
  3 *
  4 *  Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
  5 *
  6 *  GUID parsing code from ldm.c is:
  7 *   Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
  8 *   Copyright (c) 2001-2007 Anton Altaparmakov
  9 *   Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
 10 *
 
 
 
 
 11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 12 *
 13 *  This program is free software; you can redistribute it and/or modify
 14 *  it under the terms of the GNU General Public License as published by
 15 *  the Free Software Foundation; either version 2 of the License, or (at
 16 *  your option) any later version.
 17 *
 18 *  This program is distributed in the hope that it will be useful, but
 19 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 20 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 21 *  General Public License for more details.
 22 *
 23 *  You should have received a copy of the GNU General Public License along
 24 *  with this program; if not, write to the Free Software Foundation, Inc.,
 25 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 26 *
 27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 28 */
 29
 30#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
 31
 32#include <linux/kernel.h>
 33#include <linux/init.h>
 34#include <linux/types.h>
 35#include <linux/device.h>
 
 
 36#include <linux/list.h>
 37#include <linux/acpi.h>
 
 
 38#include <linux/slab.h>
 39#include <acpi/acpi_bus.h>
 40#include <acpi/acpi_drivers.h>
 
 
 
 41
 42ACPI_MODULE_NAME("wmi");
 43MODULE_AUTHOR("Carlos Corbacho");
 44MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
 45MODULE_LICENSE("GPL");
 46
 47#define ACPI_WMI_CLASS "wmi"
 48
 49static DEFINE_MUTEX(wmi_data_lock);
 50static LIST_HEAD(wmi_block_list);
 51
 52struct guid_block {
 53	char guid[16];
 54	union {
 55		char object_id[2];
 56		struct {
 57			unsigned char notify_id;
 58			unsigned char reserved;
 59		};
 60	};
 61	u8 instance_count;
 62	u8 flags;
 63};
 64
 65struct wmi_block {
 
 66	struct list_head list;
 67	struct guid_block gblock;
 68	acpi_handle handle;
 
 
 69	wmi_notify_handler handler;
 70	void *handler_data;
 71	struct device dev;
 
 
 72};
 73
 74
 75/*
 76 * If the GUID data block is marked as expensive, we must enable and
 77 * explicitily disable data collection.
 78 */
 79#define ACPI_WMI_EXPENSIVE   0x1
 80#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
 81#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
 82#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
 83
 84static int debug_event;
 85module_param(debug_event, bool, 0444);
 86MODULE_PARM_DESC(debug_event,
 87		 "Log WMI Events [0/1]");
 88
 89static int debug_dump_wdg;
 90module_param(debug_dump_wdg, bool, 0444);
 91MODULE_PARM_DESC(debug_dump_wdg,
 92		 "Dump available WMI interfaces [0/1]");
 93
 94static int acpi_wmi_remove(struct acpi_device *device, int type);
 95static int acpi_wmi_add(struct acpi_device *device);
 96static void acpi_wmi_notify(struct acpi_device *device, u32 event);
 97
 98static const struct acpi_device_id wmi_device_ids[] = {
 99	{"PNP0C14", 0},
100	{"pnp0c14", 0},
101	{"", 0},
102};
103MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
104
105static struct acpi_driver acpi_wmi_driver = {
106	.name = "wmi",
107	.class = ACPI_WMI_CLASS,
108	.ids = wmi_device_ids,
109	.ops = {
110		.add = acpi_wmi_add,
111		.remove = acpi_wmi_remove,
112		.notify = acpi_wmi_notify,
113	},
 
 
114};
115
116/*
117 * GUID parsing functions
118 */
119
120/**
121 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
122 * @src:  Pointer to at least 2 characters to convert.
123 *
124 * Convert a two character ASCII hex string to a number.
125 *
126 * Return:  0-255  Success, the byte was parsed correctly
127 *          -1     Error, an invalid character was supplied
128 */
129static int wmi_parse_hexbyte(const u8 *src)
130{
131	int h;
132	int value;
133
134	/* high part */
135	h = value = hex_to_bin(src[0]);
136	if (value < 0)
137		return -1;
138
139	/* low part */
140	value = hex_to_bin(src[1]);
141	if (value >= 0)
142		return (h << 4) | value;
143	return -1;
144}
145
146/**
147 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
148 * @src:   Memory block holding binary GUID (16 bytes)
149 * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
150 *
151 * Byte swap a binary GUID to match it's real GUID value
152 */
153static void wmi_swap_bytes(u8 *src, u8 *dest)
154{
155	int i;
156
157	for (i = 0; i <= 3; i++)
158		memcpy(dest + i, src + (3 - i), 1);
159
160	for (i = 0; i <= 1; i++)
161		memcpy(dest + 4 + i, src + (5 - i), 1);
162
163	for (i = 0; i <= 1; i++)
164		memcpy(dest + 6 + i, src + (7 - i), 1);
165
166	memcpy(dest + 8, src + 8, 8);
167}
168
169/**
170 * wmi_parse_guid - Convert GUID from ASCII to binary
171 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
172 * @dest:  Memory block to hold binary GUID (16 bytes)
173 *
174 * N.B. The GUID need not be NULL terminated.
175 *
176 * Return:  'true'   @dest contains binary GUID
177 *          'false'  @dest contents are undefined
178 */
179static bool wmi_parse_guid(const u8 *src, u8 *dest)
180{
181	static const int size[] = { 4, 2, 2, 2, 6 };
182	int i, j, v;
 
183
184	if (src[8]  != '-' || src[13] != '-' ||
185		src[18] != '-' || src[23] != '-')
186		return false;
187
188	for (j = 0; j < 5; j++, src++) {
189		for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
190			v = wmi_parse_hexbyte(src);
191			if (v < 0)
192				return false;
 
 
193		}
194	}
195
196	return true;
197}
198
199/*
200 * Convert a raw GUID to the ACII string representation
201 */
202static int wmi_gtoa(const char *in, char *out)
203{
204	int i;
 
 
205
206	for (i = 3; i >= 0; i--)
207		out += sprintf(out, "%02X", in[i] & 0xFF);
 
 
 
208
209	out += sprintf(out, "-");
210	out += sprintf(out, "%02X", in[5] & 0xFF);
211	out += sprintf(out, "%02X", in[4] & 0xFF);
212	out += sprintf(out, "-");
213	out += sprintf(out, "%02X", in[7] & 0xFF);
214	out += sprintf(out, "%02X", in[6] & 0xFF);
215	out += sprintf(out, "-");
216	out += sprintf(out, "%02X", in[8] & 0xFF);
217	out += sprintf(out, "%02X", in[9] & 0xFF);
218	out += sprintf(out, "-");
219
220	for (i = 10; i <= 15; i++)
221		out += sprintf(out, "%02X", in[i] & 0xFF);
222
223	*out = '\0';
224	return 0;
225}
226
227static bool find_guid(const char *guid_string, struct wmi_block **out)
228{
229	char tmp[16], guid_input[16];
230	struct wmi_block *wblock;
231	struct guid_block *block;
232	struct list_head *p;
233
234	wmi_parse_guid(guid_string, tmp);
235	wmi_swap_bytes(tmp, guid_input);
236
237	list_for_each(p, &wmi_block_list) {
238		wblock = list_entry(p, struct wmi_block, list);
239		block = &wblock->gblock;
240
241		if (memcmp(block->guid, guid_input, 16) == 0) {
242			if (out)
243				*out = wblock;
244			return 1;
245		}
246	}
247	return 0;
248}
249
250static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
251{
252	struct guid_block *block = NULL;
253	char method[5];
254	struct acpi_object_list input;
255	union acpi_object params[1];
256	acpi_status status;
257	acpi_handle handle;
258
259	block = &wblock->gblock;
260	handle = wblock->handle;
261
262	if (!block)
263		return AE_NOT_EXIST;
264
265	input.count = 1;
266	input.pointer = params;
267	params[0].type = ACPI_TYPE_INTEGER;
268	params[0].integer.value = enable;
269
270	snprintf(method, 5, "WE%02X", block->notify_id);
271	status = acpi_evaluate_object(handle, method, &input, NULL);
272
273	if (status != AE_OK && status != AE_NOT_FOUND)
274		return status;
275	else
276		return AE_OK;
277}
278
279/*
280 * Exported WMI functions
281 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
282/**
283 * wmi_evaluate_method - Evaluate a WMI method
284 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
285 * @instance: Instance index
286 * @method_id: Method ID to call
287 * &in: Buffer containing input for the method call
288 * &out: Empty buffer to return the method results
289 *
290 * Call an ACPI-WMI method
291 */
292acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
293u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
294{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
295	struct guid_block *block = NULL;
296	struct wmi_block *wblock = NULL;
297	acpi_handle handle;
298	acpi_status status;
299	struct acpi_object_list input;
300	union acpi_object params[3];
301	char method[5] = "WM";
302
303	if (!find_guid(guid_string, &wblock))
304		return AE_ERROR;
305
306	block = &wblock->gblock;
307	handle = wblock->handle;
308
309	if (!(block->flags & ACPI_WMI_METHOD))
310		return AE_BAD_DATA;
311
312	if (block->instance_count < instance)
313		return AE_BAD_PARAMETER;
314
315	input.count = 2;
316	input.pointer = params;
317	params[0].type = ACPI_TYPE_INTEGER;
318	params[0].integer.value = instance;
319	params[1].type = ACPI_TYPE_INTEGER;
320	params[1].integer.value = method_id;
321
322	if (in) {
323		input.count = 3;
324
325		if (block->flags & ACPI_WMI_STRING) {
326			params[2].type = ACPI_TYPE_STRING;
327		} else {
328			params[2].type = ACPI_TYPE_BUFFER;
329		}
330		params[2].buffer.length = in->length;
331		params[2].buffer.pointer = in->pointer;
332	}
333
334	strncat(method, block->object_id, 2);
335
336	status = acpi_evaluate_object(handle, method, &input, out);
337
338	return status;
339}
340EXPORT_SYMBOL_GPL(wmi_evaluate_method);
341
342/**
343 * wmi_query_block - Return contents of a WMI block
344 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
345 * @instance: Instance index
346 * &out: Empty buffer to return the contents of the data block to
347 *
348 * Return the contents of an ACPI-WMI data block to a buffer
349 */
350acpi_status wmi_query_block(const char *guid_string, u8 instance,
351struct acpi_buffer *out)
352{
353	struct guid_block *block = NULL;
354	struct wmi_block *wblock = NULL;
355	acpi_handle handle, wc_handle;
356	acpi_status status, wc_status = AE_ERROR;
357	struct acpi_object_list input, wc_input;
358	union acpi_object wc_params[1], wq_params[1];
359	char method[5];
360	char wc_method[5] = "WC";
361
362	if (!guid_string || !out)
363		return AE_BAD_PARAMETER;
364
365	if (!find_guid(guid_string, &wblock))
366		return AE_ERROR;
367
368	block = &wblock->gblock;
369	handle = wblock->handle;
370
371	if (block->instance_count < instance)
372		return AE_BAD_PARAMETER;
373
374	/* Check GUID is a data block */
375	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
376		return AE_ERROR;
377
378	input.count = 1;
379	input.pointer = wq_params;
380	wq_params[0].type = ACPI_TYPE_INTEGER;
381	wq_params[0].integer.value = instance;
382
 
 
 
383	/*
384	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
385	 * enable collection.
386	 */
387	if (block->flags & ACPI_WMI_EXPENSIVE) {
388		wc_input.count = 1;
389		wc_input.pointer = wc_params;
390		wc_params[0].type = ACPI_TYPE_INTEGER;
391		wc_params[0].integer.value = 1;
392
393		strncat(wc_method, block->object_id, 2);
394
395		/*
396		 * Some GUIDs break the specification by declaring themselves
397		 * expensive, but have no corresponding WCxx method. So we
398		 * should not fail if this happens.
399		 */
400		wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
401		if (ACPI_SUCCESS(wc_status))
402			wc_status = acpi_evaluate_object(handle, wc_method,
403				&wc_input, NULL);
404	}
405
406	strcpy(method, "WQ");
407	strncat(method, block->object_id, 2);
408
409	status = acpi_evaluate_object(handle, method, &input, out);
410
411	/*
412	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
413	 * the WQxx method failed - we should disable collection anyway.
414	 */
415	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
416		wc_params[0].integer.value = 0;
417		status = acpi_evaluate_object(handle,
418		wc_method, &wc_input, NULL);
419	}
420
421	return status;
422}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
423EXPORT_SYMBOL_GPL(wmi_query_block);
424
 
 
 
 
 
 
 
 
 
 
 
 
425/**
426 * wmi_set_block - Write to a WMI block
427 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
428 * @instance: Instance index
429 * &in: Buffer containing new values for the data block
430 *
431 * Write the contents of the input buffer to an ACPI-WMI data block
432 */
433acpi_status wmi_set_block(const char *guid_string, u8 instance,
434const struct acpi_buffer *in)
435{
436	struct guid_block *block = NULL;
437	struct wmi_block *wblock = NULL;
438	acpi_handle handle;
439	struct acpi_object_list input;
440	union acpi_object params[2];
441	char method[5] = "WS";
442
443	if (!guid_string || !in)
444		return AE_BAD_DATA;
445
446	if (!find_guid(guid_string, &wblock))
447		return AE_ERROR;
448
449	block = &wblock->gblock;
450	handle = wblock->handle;
451
452	if (block->instance_count < instance)
453		return AE_BAD_PARAMETER;
454
455	/* Check GUID is a data block */
456	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
457		return AE_ERROR;
458
459	input.count = 2;
460	input.pointer = params;
461	params[0].type = ACPI_TYPE_INTEGER;
462	params[0].integer.value = instance;
463
464	if (block->flags & ACPI_WMI_STRING) {
465		params[1].type = ACPI_TYPE_STRING;
466	} else {
467		params[1].type = ACPI_TYPE_BUFFER;
468	}
469	params[1].buffer.length = in->length;
470	params[1].buffer.pointer = in->pointer;
471
472	strncat(method, block->object_id, 2);
473
474	return acpi_evaluate_object(handle, method, &input, NULL);
475}
476EXPORT_SYMBOL_GPL(wmi_set_block);
477
478static void wmi_dump_wdg(const struct guid_block *g)
479{
480	char guid_string[37];
481
482	wmi_gtoa(g->guid, guid_string);
483
484	pr_info("%s:\n", guid_string);
485	pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
486	pr_info("\tnotify_id: %02X\n", g->notify_id);
487	pr_info("\treserved: %02X\n", g->reserved);
488	pr_info("\tinstance_count: %d\n", g->instance_count);
489	pr_info("\tflags: %#x", g->flags);
490	if (g->flags) {
491		if (g->flags & ACPI_WMI_EXPENSIVE)
492			pr_cont(" ACPI_WMI_EXPENSIVE");
493		if (g->flags & ACPI_WMI_METHOD)
494			pr_cont(" ACPI_WMI_METHOD");
495		if (g->flags & ACPI_WMI_STRING)
496			pr_cont(" ACPI_WMI_STRING");
497		if (g->flags & ACPI_WMI_EVENT)
498			pr_cont(" ACPI_WMI_EVENT");
499	}
500	pr_cont("\n");
501
502}
503
504static void wmi_notify_debug(u32 value, void *context)
505{
506	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
507	union acpi_object *obj;
508	acpi_status status;
509
510	status = wmi_get_event_data(value, &response);
511	if (status != AE_OK) {
512		pr_info("bad event status 0x%x\n", status);
513		return;
514	}
515
516	obj = (union acpi_object *)response.pointer;
517
518	if (!obj)
519		return;
520
521	pr_info("DEBUG Event ");
522	switch(obj->type) {
523	case ACPI_TYPE_BUFFER:
524		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
525		break;
526	case ACPI_TYPE_STRING:
527		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
528		break;
529	case ACPI_TYPE_INTEGER:
530		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
531		break;
532	case ACPI_TYPE_PACKAGE:
533		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
534		break;
535	default:
536		pr_cont("object type 0x%X\n", obj->type);
537	}
538	kfree(obj);
539}
540
541/**
542 * wmi_install_notify_handler - Register handler for WMI events
543 * @handler: Function to handle notifications
544 * @data: Data to be returned to handler when event is fired
545 *
546 * Register a handler for events sent to the ACPI-WMI mapper device.
547 */
548acpi_status wmi_install_notify_handler(const char *guid,
549wmi_notify_handler handler, void *data)
550{
551	struct wmi_block *block;
552	acpi_status status = AE_NOT_EXIST;
553	char tmp[16], guid_input[16];
554	struct list_head *p;
555
556	if (!guid || !handler)
557		return AE_BAD_PARAMETER;
558
559	wmi_parse_guid(guid, tmp);
560	wmi_swap_bytes(tmp, guid_input);
561
562	list_for_each(p, &wmi_block_list) {
563		acpi_status wmi_status;
564		block = list_entry(p, struct wmi_block, list);
565
566		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
567			if (block->handler &&
568			    block->handler != wmi_notify_debug)
569				return AE_ALREADY_ACQUIRED;
570
571			block->handler = handler;
572			block->handler_data = data;
573
574			wmi_status = wmi_method_enable(block, 1);
575			if ((wmi_status != AE_OK) ||
576			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
577				status = wmi_status;
578		}
579	}
580
581	return status;
582}
583EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
584
585/**
586 * wmi_uninstall_notify_handler - Unregister handler for WMI events
587 *
588 * Unregister handler for events sent to the ACPI-WMI mapper device.
589 */
590acpi_status wmi_remove_notify_handler(const char *guid)
591{
592	struct wmi_block *block;
593	acpi_status status = AE_NOT_EXIST;
594	char tmp[16], guid_input[16];
595	struct list_head *p;
596
597	if (!guid)
598		return AE_BAD_PARAMETER;
599
600	wmi_parse_guid(guid, tmp);
601	wmi_swap_bytes(tmp, guid_input);
602
603	list_for_each(p, &wmi_block_list) {
604		acpi_status wmi_status;
605		block = list_entry(p, struct wmi_block, list);
606
607		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
608			if (!block->handler ||
609			    block->handler == wmi_notify_debug)
610				return AE_NULL_ENTRY;
611
612			if (debug_event) {
613				block->handler = wmi_notify_debug;
614				status = AE_OK;
615			} else {
616				wmi_status = wmi_method_enable(block, 0);
617				block->handler = NULL;
618				block->handler_data = NULL;
619				if ((wmi_status != AE_OK) ||
620				    ((wmi_status == AE_OK) &&
621				     (status == AE_NOT_EXIST)))
622					status = wmi_status;
623			}
624		}
625	}
626
627	return status;
628}
629EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
630
631/**
632 * wmi_get_event_data - Get WMI data associated with an event
633 *
634 * @event: Event to find
635 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
636 *
637 * Returns extra data associated with an event in WMI.
638 */
639acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
640{
641	struct acpi_object_list input;
642	union acpi_object params[1];
643	struct guid_block *gblock;
644	struct wmi_block *wblock;
645	struct list_head *p;
646
647	input.count = 1;
648	input.pointer = params;
649	params[0].type = ACPI_TYPE_INTEGER;
650	params[0].integer.value = event;
651
652	list_for_each(p, &wmi_block_list) {
653		wblock = list_entry(p, struct wmi_block, list);
654		gblock = &wblock->gblock;
655
656		if ((gblock->flags & ACPI_WMI_EVENT) &&
657			(gblock->notify_id == event))
658			return acpi_evaluate_object(wblock->handle, "_WED",
659				&input, out);
660	}
661
662	return AE_NOT_FOUND;
663}
664EXPORT_SYMBOL_GPL(wmi_get_event_data);
665
666/**
667 * wmi_has_guid - Check if a GUID is available
668 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
669 *
670 * Check if a given GUID is defined by _WDG
671 */
672bool wmi_has_guid(const char *guid_string)
673{
674	return find_guid(guid_string, NULL);
675}
676EXPORT_SYMBOL_GPL(wmi_has_guid);
677
 
 
 
 
 
 
 
 
 
 
678/*
679 * sysfs interface
680 */
681static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
682			     char *buf)
683{
684	char guid_string[37];
685	struct wmi_block *wblock;
686
687	wblock = dev_get_drvdata(dev);
688	if (!wblock)
689		return -ENOMEM;
 
 
 
 
 
 
 
 
 
690
691	wmi_gtoa(wblock->gblock.guid, guid_string);
 
 
 
692
693	return sprintf(buf, "wmi:%s\n", guid_string);
694}
 
695
696static struct device_attribute wmi_dev_attrs[] = {
697	__ATTR_RO(modalias),
698	__ATTR_NULL
 
 
 
 
 
 
 
 
 
 
 
 
 
699};
 
700
701static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 
702{
703	char guid_string[37];
704
705	struct wmi_block *wblock;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
706
707	if (add_uevent_var(env, "MODALIAS="))
708		return -ENOMEM;
709
710	wblock = dev_get_drvdata(dev);
711	if (!wblock)
712		return -ENOMEM;
713
714	wmi_gtoa(wblock->gblock.guid, guid_string);
 
 
 
 
 
715
716	strcpy(&env->buf[env->buflen - 1], "wmi:");
717	memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
718	env->buflen += 40;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
719
720	return 0;
721}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
722
723static void wmi_dev_free(struct device *dev)
 
 
 
 
 
 
 
724{
725	struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
726
727	kfree(wmi_block);
 
 
728}
729
730static struct class wmi_class = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
731	.name = "wmi",
732	.dev_release = wmi_dev_free,
733	.dev_uevent = wmi_dev_uevent,
734	.dev_attrs = wmi_dev_attrs,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
735};
736
737static int wmi_create_device(const struct guid_block *gblock,
738			     struct wmi_block *wblock, acpi_handle handle)
 
 
 
 
 
 
 
 
739{
740	char guid_string[37];
 
 
741
742	wblock->dev.class = &wmi_class;
 
 
 
 
 
 
 
 
 
743
744	wmi_gtoa(gblock->guid, guid_string);
745	dev_set_name(&wblock->dev, guid_string);
 
 
 
 
 
 
 
 
 
 
 
 
 
746
747	dev_set_drvdata(&wblock->dev, wblock);
748
749	return device_register(&wblock->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
750}
751
752static void wmi_free_devices(void)
753{
754	struct wmi_block *wblock, *next;
755
756	/* Delete devices for all the GUIDs */
757	list_for_each_entry_safe(wblock, next, &wmi_block_list, list)
758		if (wblock->dev.class)
759			device_unregister(&wblock->dev);
 
 
 
760}
761
762static bool guid_already_parsed(const char *guid_string)
 
763{
764	struct wmi_block *wblock;
765
766	list_for_each_entry(wblock, &wmi_block_list, list)
767		if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
 
 
 
 
 
 
 
 
768			return true;
 
 
769
770	return false;
771}
772
773/*
774 * Parse the _WDG method for the GUID data blocks
775 */
776static acpi_status parse_wdg(acpi_handle handle)
777{
778	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
779	union acpi_object *obj;
780	const struct guid_block *gblock;
781	struct wmi_block *wblock;
 
782	acpi_status status;
783	int retval;
784	u32 i, total;
785
786	status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
787	if (ACPI_FAILURE(status))
788		return -ENXIO;
789
790	obj = (union acpi_object *) out.pointer;
791	if (!obj)
792		return -ENXIO;
793
794	if (obj->type != ACPI_TYPE_BUFFER) {
795		retval = -ENXIO;
796		goto out_free_pointer;
797	}
798
799	gblock = (const struct guid_block *)obj->buffer.pointer;
800	total = obj->buffer.length / sizeof(struct guid_block);
801
802	for (i = 0; i < total; i++) {
803		if (debug_dump_wdg)
804			wmi_dump_wdg(&gblock[i]);
805
 
 
 
 
 
 
 
 
 
806		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
807		if (!wblock)
808			return AE_NO_MEMORY;
 
 
809
810		wblock->handle = handle;
811		wblock->gblock = gblock[i];
812
813		/*
814		  Some WMI devices, like those for nVidia hooks, have a
815		  duplicate GUID. It's not clear what we should do in this
816		  case yet, so for now, we'll just ignore the duplicate
817		  for device creation.
818		*/
819		if (!guid_already_parsed(gblock[i].guid)) {
820			retval = wmi_create_device(&gblock[i], wblock, handle);
821			if (retval) {
822				wmi_free_devices();
823				goto out_free_pointer;
824			}
825		}
826
827		list_add_tail(&wblock->list, &wmi_block_list);
828
829		if (debug_event) {
830			wblock->handler = wmi_notify_debug;
831			wmi_method_enable(wblock, 1);
832		}
833	}
834
835	retval = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
836
837out_free_pointer:
838	kfree(out.pointer);
839
840	return retval;
841}
842
843/*
844 * WMI can have EmbeddedControl access regions. In which case, we just want to
845 * hand these off to the EC driver.
846 */
847static acpi_status
848acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
849		      u32 bits, u64 *value,
850		      void *handler_context, void *region_context)
851{
852	int result = 0, i = 0;
853	u8 temp = 0;
854
855	if ((address > 0xFF) || !value)
856		return AE_BAD_PARAMETER;
857
858	if (function != ACPI_READ && function != ACPI_WRITE)
859		return AE_BAD_PARAMETER;
860
861	if (bits != 8)
862		return AE_BAD_PARAMETER;
863
864	if (function == ACPI_READ) {
865		result = ec_read(address, &temp);
866		(*value) |= ((u64)temp) << i;
867	} else {
868		temp = 0xff & ((*value) >> i);
869		result = ec_write(address, temp);
870	}
871
872	switch (result) {
873	case -EINVAL:
874		return AE_BAD_PARAMETER;
875		break;
876	case -ENODEV:
877		return AE_NOT_FOUND;
878		break;
879	case -ETIME:
880		return AE_TIME;
881		break;
882	default:
883		return AE_OK;
884	}
885}
886
887static void acpi_wmi_notify(struct acpi_device *device, u32 event)
 
888{
889	struct guid_block *block;
890	struct wmi_block *wblock;
891	struct list_head *p;
892	char guid_string[37];
893
894	list_for_each(p, &wmi_block_list) {
895		wblock = list_entry(p, struct wmi_block, list);
896		block = &wblock->gblock;
897
898		if ((block->flags & ACPI_WMI_EVENT) &&
899			(block->notify_id == event)) {
900			if (wblock->handler)
901				wblock->handler(event, wblock->handler_data);
902			if (debug_event) {
903				wmi_gtoa(wblock->gblock.guid, guid_string);
904				pr_info("DEBUG Event GUID: %s\n", guid_string);
905			}
906
907			acpi_bus_generate_netlink_event(
908				device->pnp.device_class, dev_name(&device->dev),
909				event, 0);
910			break;
911		}
912	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
913}
914
915static int acpi_wmi_remove(struct acpi_device *device, int type)
916{
917	acpi_remove_address_space_handler(device->handle,
 
 
 
 
918				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
919	wmi_free_devices();
 
920
921	return 0;
922}
923
924static int acpi_wmi_add(struct acpi_device *device)
925{
 
 
926	acpi_status status;
927	int error;
928
929	status = acpi_install_address_space_handler(device->handle,
 
 
 
 
 
 
930						    ACPI_ADR_SPACE_EC,
931						    &acpi_wmi_ec_space_handler,
932						    NULL, NULL);
933	if (ACPI_FAILURE(status)) {
934		pr_err("Error installing EC region handler\n");
935		return -ENODEV;
936	}
937
938	error = parse_wdg(device->handle);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
939	if (error) {
940		acpi_remove_address_space_handler(device->handle,
941						  ACPI_ADR_SPACE_EC,
942						  &acpi_wmi_ec_space_handler);
943		pr_err("Failed to parse WDG method\n");
944		return error;
945	}
946
947	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
948}
 
 
 
 
 
 
 
949
950static int __init acpi_wmi_init(void)
951{
952	int error;
953
954	if (acpi_disabled)
955		return -ENODEV;
956
957	error = class_register(&wmi_class);
958	if (error)
959		return error;
960
961	error = acpi_bus_register_driver(&acpi_wmi_driver);
 
 
 
 
962	if (error) {
963		pr_err("Error loading mapper\n");
964		class_unregister(&wmi_class);
965		return error;
966	}
967
968	pr_info("Mapper loaded\n");
969	return 0;
 
 
 
 
 
 
 
 
970}
971
972static void __exit acpi_wmi_exit(void)
973{
974	acpi_bus_unregister_driver(&acpi_wmi_driver);
975	class_unregister(&wmi_class);
976
977	pr_info("Mapper unloaded\n");
978}
979
980subsys_initcall(acpi_wmi_init);
981module_exit(acpi_wmi_exit);
v4.17
   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 *  WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
  12 *    Copyright (C) 2015 Andrew Lutomirski
  13 *    Copyright (C) 2017 VMware, Inc. All Rights Reserved.
  14 *
  15 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  16 *
  17 *  This program is free software; you can redistribute it and/or modify
  18 *  it under the terms of the GNU General Public License as published by
  19 *  the Free Software Foundation; either version 2 of the License, or (at
  20 *  your option) any later version.
  21 *
  22 *  This program is distributed in the hope that it will be useful, but
  23 *  WITHOUT ANY WARRANTY; without even the implied warranty of
  24 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  25 *  General Public License for more details.
  26 *
  27 *  You should have received a copy of the GNU General Public License along
  28 *  with this program; if not, write to the Free Software Foundation, Inc.,
  29 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  30 *
  31 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  32 */
  33
  34#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
  35
  36#include <linux/acpi.h>
 
 
  37#include <linux/device.h>
  38#include <linux/init.h>
  39#include <linux/kernel.h>
  40#include <linux/list.h>
  41#include <linux/miscdevice.h>
  42#include <linux/module.h>
  43#include <linux/platform_device.h>
  44#include <linux/slab.h>
  45#include <linux/types.h>
  46#include <linux/uaccess.h>
  47#include <linux/uuid.h>
  48#include <linux/wmi.h>
  49#include <uapi/linux/wmi.h>
  50
  51ACPI_MODULE_NAME("wmi");
  52MODULE_AUTHOR("Carlos Corbacho");
  53MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
  54MODULE_LICENSE("GPL");
  55
 
 
 
  56static LIST_HEAD(wmi_block_list);
  57
  58struct guid_block {
  59	char guid[16];
  60	union {
  61		char object_id[2];
  62		struct {
  63			unsigned char notify_id;
  64			unsigned char reserved;
  65		};
  66	};
  67	u8 instance_count;
  68	u8 flags;
  69};
  70
  71struct wmi_block {
  72	struct wmi_device dev;
  73	struct list_head list;
  74	struct guid_block gblock;
  75	struct miscdevice char_dev;
  76	struct mutex char_mutex;
  77	struct acpi_device *acpi_device;
  78	wmi_notify_handler handler;
  79	void *handler_data;
  80	u64 req_buf_size;
  81
  82	bool read_takes_no_args;
  83};
  84
  85
  86/*
  87 * If the GUID data block is marked as expensive, we must enable and
  88 * explicitily disable data collection.
  89 */
  90#define ACPI_WMI_EXPENSIVE   0x1
  91#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
  92#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
  93#define ACPI_WMI_EVENT       0x8	/* GUID is an event */
  94
  95static bool debug_event;
  96module_param(debug_event, bool, 0444);
  97MODULE_PARM_DESC(debug_event,
  98		 "Log WMI Events [0/1]");
  99
 100static bool debug_dump_wdg;
 101module_param(debug_dump_wdg, bool, 0444);
 102MODULE_PARM_DESC(debug_dump_wdg,
 103		 "Dump available WMI interfaces [0/1]");
 104
 105static int acpi_wmi_remove(struct platform_device *device);
 106static int acpi_wmi_probe(struct platform_device *device);
 
 107
 108static const struct acpi_device_id wmi_device_ids[] = {
 109	{"PNP0C14", 0},
 110	{"pnp0c14", 0},
 111	{"", 0},
 112};
 113MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
 114
 115static struct platform_driver acpi_wmi_driver = {
 116	.driver = {
 117		.name = "acpi-wmi",
 118		.acpi_match_table = wmi_device_ids,
 
 
 
 
 119	},
 120	.probe = acpi_wmi_probe,
 121	.remove = acpi_wmi_remove,
 122};
 123
 124/*
 125 * GUID parsing functions
 126 */
 127
 128static bool find_guid(const char *guid_string, struct wmi_block **out)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 129{
 130	uuid_le guid_input;
 131	struct wmi_block *wblock;
 132	struct guid_block *block;
 133
 134	if (uuid_le_to_bin(guid_string, &guid_input))
 
 135		return false;
 136
 137	list_for_each_entry(wblock, &wmi_block_list, list) {
 138		block = &wblock->gblock;
 139
 140		if (memcmp(block->guid, &guid_input, 16) == 0) {
 141			if (out)
 142				*out = wblock;
 143			return true;
 144		}
 145	}
 146	return false;
 
 147}
 148
 149static int get_subobj_info(acpi_handle handle, const char *pathname,
 150			   struct acpi_device_info **info)
 
 
 151{
 152	struct acpi_device_info *dummy_info, **info_ptr;
 153	acpi_handle subobj_handle;
 154	acpi_status status;
 155
 156	status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
 157	if (status == AE_NOT_FOUND)
 158		return -ENOENT;
 159	else if (ACPI_FAILURE(status))
 160		return -EIO;
 161
 162	info_ptr = info ? info : &dummy_info;
 163	status = acpi_get_object_info(subobj_handle, info_ptr);
 164	if (ACPI_FAILURE(status))
 165		return -EIO;
 
 
 
 
 
 
 166
 167	if (!info)
 168		kfree(dummy_info);
 169
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 170	return 0;
 171}
 172
 173static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
 174{
 175	struct guid_block *block = NULL;
 176	char method[5];
 
 
 177	acpi_status status;
 178	acpi_handle handle;
 179
 180	block = &wblock->gblock;
 181	handle = wblock->acpi_device->handle;
 
 
 
 
 
 
 
 
 182
 183	snprintf(method, 5, "WE%02X", block->notify_id);
 184	status = acpi_execute_simple_method(handle, method, enable);
 185
 186	if (status != AE_OK && status != AE_NOT_FOUND)
 187		return status;
 188	else
 189		return AE_OK;
 190}
 191
 192/*
 193 * Exported WMI functions
 194 */
 195
 196/**
 197 * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
 198 * @wdev: A wmi bus device from a driver
 199 * @instance: Instance index
 200 *
 201 * Allocates memory needed for buffer, stores the buffer size in that memory
 202 */
 203int set_required_buffer_size(struct wmi_device *wdev, u64 length)
 204{
 205	struct wmi_block *wblock;
 206
 207	wblock = container_of(wdev, struct wmi_block, dev);
 208	wblock->req_buf_size = length;
 209
 210	return 0;
 211}
 212EXPORT_SYMBOL_GPL(set_required_buffer_size);
 213
 214/**
 215 * wmi_evaluate_method - Evaluate a WMI method
 216 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 217 * @instance: Instance index
 218 * @method_id: Method ID to call
 219 * &in: Buffer containing input for the method call
 220 * &out: Empty buffer to return the method results
 221 *
 222 * Call an ACPI-WMI method
 223 */
 224acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
 225u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 226{
 227	struct wmi_block *wblock = NULL;
 228
 229	if (!find_guid(guid_string, &wblock))
 230		return AE_ERROR;
 231	return wmidev_evaluate_method(&wblock->dev, instance, method_id,
 232				      in, out);
 233}
 234EXPORT_SYMBOL_GPL(wmi_evaluate_method);
 235
 236/**
 237 * wmidev_evaluate_method - Evaluate a WMI method
 238 * @wdev: A wmi bus device from a driver
 239 * @instance: Instance index
 240 * @method_id: Method ID to call
 241 * &in: Buffer containing input for the method call
 242 * &out: Empty buffer to return the method results
 243 *
 244 * Call an ACPI-WMI method
 245 */
 246acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance,
 247	u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 248{
 249	struct guid_block *block = NULL;
 250	struct wmi_block *wblock = NULL;
 251	acpi_handle handle;
 252	acpi_status status;
 253	struct acpi_object_list input;
 254	union acpi_object params[3];
 255	char method[5] = "WM";
 256
 257	wblock = container_of(wdev, struct wmi_block, dev);
 
 
 258	block = &wblock->gblock;
 259	handle = wblock->acpi_device->handle;
 260
 261	if (!(block->flags & ACPI_WMI_METHOD))
 262		return AE_BAD_DATA;
 263
 264	if (block->instance_count <= instance)
 265		return AE_BAD_PARAMETER;
 266
 267	input.count = 2;
 268	input.pointer = params;
 269	params[0].type = ACPI_TYPE_INTEGER;
 270	params[0].integer.value = instance;
 271	params[1].type = ACPI_TYPE_INTEGER;
 272	params[1].integer.value = method_id;
 273
 274	if (in) {
 275		input.count = 3;
 276
 277		if (block->flags & ACPI_WMI_STRING) {
 278			params[2].type = ACPI_TYPE_STRING;
 279		} else {
 280			params[2].type = ACPI_TYPE_BUFFER;
 281		}
 282		params[2].buffer.length = in->length;
 283		params[2].buffer.pointer = in->pointer;
 284	}
 285
 286	strncat(method, block->object_id, 2);
 287
 288	status = acpi_evaluate_object(handle, method, &input, out);
 289
 290	return status;
 291}
 292EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
 293
 294static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
 295				 struct acpi_buffer *out)
 
 
 
 
 
 
 
 
 296{
 297	struct guid_block *block = NULL;
 298	acpi_handle handle;
 
 299	acpi_status status, wc_status = AE_ERROR;
 300	struct acpi_object_list input;
 301	union acpi_object wq_params[1];
 302	char method[5];
 303	char wc_method[5] = "WC";
 304
 305	if (!out)
 306		return AE_BAD_PARAMETER;
 307
 
 
 
 308	block = &wblock->gblock;
 309	handle = wblock->acpi_device->handle;
 310
 311	if (block->instance_count <= instance)
 312		return AE_BAD_PARAMETER;
 313
 314	/* Check GUID is a data block */
 315	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 316		return AE_ERROR;
 317
 318	input.count = 1;
 319	input.pointer = wq_params;
 320	wq_params[0].type = ACPI_TYPE_INTEGER;
 321	wq_params[0].integer.value = instance;
 322
 323	if (instance == 0 && wblock->read_takes_no_args)
 324		input.count = 0;
 325
 326	/*
 327	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
 328	 * enable collection.
 329	 */
 330	if (block->flags & ACPI_WMI_EXPENSIVE) {
 
 
 
 
 
 331		strncat(wc_method, block->object_id, 2);
 332
 333		/*
 334		 * Some GUIDs break the specification by declaring themselves
 335		 * expensive, but have no corresponding WCxx method. So we
 336		 * should not fail if this happens.
 337		 */
 338		if (acpi_has_method(handle, wc_method))
 339			wc_status = acpi_execute_simple_method(handle,
 340								wc_method, 1);
 
 341	}
 342
 343	strcpy(method, "WQ");
 344	strncat(method, block->object_id, 2);
 345
 346	status = acpi_evaluate_object(handle, method, &input, out);
 347
 348	/*
 349	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
 350	 * the WQxx method failed - we should disable collection anyway.
 351	 */
 352	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
 353		status = acpi_execute_simple_method(handle, wc_method, 0);
 
 
 354	}
 355
 356	return status;
 357}
 358
 359/**
 360 * wmi_query_block - Return contents of a WMI block (deprecated)
 361 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 362 * @instance: Instance index
 363 * &out: Empty buffer to return the contents of the data block to
 364 *
 365 * Return the contents of an ACPI-WMI data block to a buffer
 366 */
 367acpi_status wmi_query_block(const char *guid_string, u8 instance,
 368			    struct acpi_buffer *out)
 369{
 370	struct wmi_block *wblock;
 371
 372	if (!guid_string)
 373		return AE_BAD_PARAMETER;
 374
 375	if (!find_guid(guid_string, &wblock))
 376		return AE_ERROR;
 377
 378	return __query_block(wblock, instance, out);
 379}
 380EXPORT_SYMBOL_GPL(wmi_query_block);
 381
 382union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
 383{
 384	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
 385	struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
 386
 387	if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
 388		return NULL;
 389
 390	return (union acpi_object *)out.pointer;
 391}
 392EXPORT_SYMBOL_GPL(wmidev_block_query);
 393
 394/**
 395 * wmi_set_block - Write to a WMI block
 396 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 397 * @instance: Instance index
 398 * &in: Buffer containing new values for the data block
 399 *
 400 * Write the contents of the input buffer to an ACPI-WMI data block
 401 */
 402acpi_status wmi_set_block(const char *guid_string, u8 instance,
 403			  const struct acpi_buffer *in)
 404{
 405	struct guid_block *block = NULL;
 406	struct wmi_block *wblock = NULL;
 407	acpi_handle handle;
 408	struct acpi_object_list input;
 409	union acpi_object params[2];
 410	char method[5] = "WS";
 411
 412	if (!guid_string || !in)
 413		return AE_BAD_DATA;
 414
 415	if (!find_guid(guid_string, &wblock))
 416		return AE_ERROR;
 417
 418	block = &wblock->gblock;
 419	handle = wblock->acpi_device->handle;
 420
 421	if (block->instance_count <= instance)
 422		return AE_BAD_PARAMETER;
 423
 424	/* Check GUID is a data block */
 425	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 426		return AE_ERROR;
 427
 428	input.count = 2;
 429	input.pointer = params;
 430	params[0].type = ACPI_TYPE_INTEGER;
 431	params[0].integer.value = instance;
 432
 433	if (block->flags & ACPI_WMI_STRING) {
 434		params[1].type = ACPI_TYPE_STRING;
 435	} else {
 436		params[1].type = ACPI_TYPE_BUFFER;
 437	}
 438	params[1].buffer.length = in->length;
 439	params[1].buffer.pointer = in->pointer;
 440
 441	strncat(method, block->object_id, 2);
 442
 443	return acpi_evaluate_object(handle, method, &input, NULL);
 444}
 445EXPORT_SYMBOL_GPL(wmi_set_block);
 446
 447static void wmi_dump_wdg(const struct guid_block *g)
 448{
 449	pr_info("%pUL:\n", g->guid);
 450	if (g->flags & ACPI_WMI_EVENT)
 451		pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
 452	else
 453		pr_info("\tobject_id: %2pE\n", g->object_id);
 
 
 
 454	pr_info("\tinstance_count: %d\n", g->instance_count);
 455	pr_info("\tflags: %#x", g->flags);
 456	if (g->flags) {
 457		if (g->flags & ACPI_WMI_EXPENSIVE)
 458			pr_cont(" ACPI_WMI_EXPENSIVE");
 459		if (g->flags & ACPI_WMI_METHOD)
 460			pr_cont(" ACPI_WMI_METHOD");
 461		if (g->flags & ACPI_WMI_STRING)
 462			pr_cont(" ACPI_WMI_STRING");
 463		if (g->flags & ACPI_WMI_EVENT)
 464			pr_cont(" ACPI_WMI_EVENT");
 465	}
 466	pr_cont("\n");
 467
 468}
 469
 470static void wmi_notify_debug(u32 value, void *context)
 471{
 472	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
 473	union acpi_object *obj;
 474	acpi_status status;
 475
 476	status = wmi_get_event_data(value, &response);
 477	if (status != AE_OK) {
 478		pr_info("bad event status 0x%x\n", status);
 479		return;
 480	}
 481
 482	obj = (union acpi_object *)response.pointer;
 483
 484	if (!obj)
 485		return;
 486
 487	pr_info("DEBUG Event ");
 488	switch(obj->type) {
 489	case ACPI_TYPE_BUFFER:
 490		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
 491		break;
 492	case ACPI_TYPE_STRING:
 493		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
 494		break;
 495	case ACPI_TYPE_INTEGER:
 496		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
 497		break;
 498	case ACPI_TYPE_PACKAGE:
 499		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
 500		break;
 501	default:
 502		pr_cont("object type 0x%X\n", obj->type);
 503	}
 504	kfree(obj);
 505}
 506
 507/**
 508 * wmi_install_notify_handler - Register handler for WMI events
 509 * @handler: Function to handle notifications
 510 * @data: Data to be returned to handler when event is fired
 511 *
 512 * Register a handler for events sent to the ACPI-WMI mapper device.
 513 */
 514acpi_status wmi_install_notify_handler(const char *guid,
 515wmi_notify_handler handler, void *data)
 516{
 517	struct wmi_block *block;
 518	acpi_status status = AE_NOT_EXIST;
 519	uuid_le guid_input;
 
 520
 521	if (!guid || !handler)
 522		return AE_BAD_PARAMETER;
 523
 524	if (uuid_le_to_bin(guid, &guid_input))
 525		return AE_BAD_PARAMETER;
 526
 527	list_for_each_entry(block, &wmi_block_list, list) {
 528		acpi_status wmi_status;
 
 529
 530		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 531			if (block->handler &&
 532			    block->handler != wmi_notify_debug)
 533				return AE_ALREADY_ACQUIRED;
 534
 535			block->handler = handler;
 536			block->handler_data = data;
 537
 538			wmi_status = wmi_method_enable(block, 1);
 539			if ((wmi_status != AE_OK) ||
 540			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
 541				status = wmi_status;
 542		}
 543	}
 544
 545	return status;
 546}
 547EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
 548
 549/**
 550 * wmi_uninstall_notify_handler - Unregister handler for WMI events
 551 *
 552 * Unregister handler for events sent to the ACPI-WMI mapper device.
 553 */
 554acpi_status wmi_remove_notify_handler(const char *guid)
 555{
 556	struct wmi_block *block;
 557	acpi_status status = AE_NOT_EXIST;
 558	uuid_le guid_input;
 
 559
 560	if (!guid)
 561		return AE_BAD_PARAMETER;
 562
 563	if (uuid_le_to_bin(guid, &guid_input))
 564		return AE_BAD_PARAMETER;
 565
 566	list_for_each_entry(block, &wmi_block_list, list) {
 567		acpi_status wmi_status;
 
 568
 569		if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
 570			if (!block->handler ||
 571			    block->handler == wmi_notify_debug)
 572				return AE_NULL_ENTRY;
 573
 574			if (debug_event) {
 575				block->handler = wmi_notify_debug;
 576				status = AE_OK;
 577			} else {
 578				wmi_status = wmi_method_enable(block, 0);
 579				block->handler = NULL;
 580				block->handler_data = NULL;
 581				if ((wmi_status != AE_OK) ||
 582				    ((wmi_status == AE_OK) &&
 583				     (status == AE_NOT_EXIST)))
 584					status = wmi_status;
 585			}
 586		}
 587	}
 588
 589	return status;
 590}
 591EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
 592
 593/**
 594 * wmi_get_event_data - Get WMI data associated with an event
 595 *
 596 * @event: Event to find
 597 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
 598 *
 599 * Returns extra data associated with an event in WMI.
 600 */
 601acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
 602{
 603	struct acpi_object_list input;
 604	union acpi_object params[1];
 605	struct guid_block *gblock;
 606	struct wmi_block *wblock;
 
 607
 608	input.count = 1;
 609	input.pointer = params;
 610	params[0].type = ACPI_TYPE_INTEGER;
 611	params[0].integer.value = event;
 612
 613	list_for_each_entry(wblock, &wmi_block_list, list) {
 
 614		gblock = &wblock->gblock;
 615
 616		if ((gblock->flags & ACPI_WMI_EVENT) &&
 617			(gblock->notify_id == event))
 618			return acpi_evaluate_object(wblock->acpi_device->handle,
 619				"_WED", &input, out);
 620	}
 621
 622	return AE_NOT_FOUND;
 623}
 624EXPORT_SYMBOL_GPL(wmi_get_event_data);
 625
 626/**
 627 * wmi_has_guid - Check if a GUID is available
 628 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 629 *
 630 * Check if a given GUID is defined by _WDG
 631 */
 632bool wmi_has_guid(const char *guid_string)
 633{
 634	return find_guid(guid_string, NULL);
 635}
 636EXPORT_SYMBOL_GPL(wmi_has_guid);
 637
 638static struct wmi_block *dev_to_wblock(struct device *dev)
 639{
 640	return container_of(dev, struct wmi_block, dev.dev);
 641}
 642
 643static struct wmi_device *dev_to_wdev(struct device *dev)
 644{
 645	return container_of(dev, struct wmi_device, dev);
 646}
 647
 648/*
 649 * sysfs interface
 650 */
 651static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 652			     char *buf)
 653{
 654	struct wmi_block *wblock = dev_to_wblock(dev);
 
 655
 656	return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
 657}
 658static DEVICE_ATTR_RO(modalias);
 659
 660static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
 661			 char *buf)
 662{
 663	struct wmi_block *wblock = dev_to_wblock(dev);
 664
 665	return sprintf(buf, "%pUL\n", wblock->gblock.guid);
 666}
 667static DEVICE_ATTR_RO(guid);
 668
 669static ssize_t instance_count_show(struct device *dev,
 670				   struct device_attribute *attr, char *buf)
 671{
 672	struct wmi_block *wblock = dev_to_wblock(dev);
 673
 674	return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
 675}
 676static DEVICE_ATTR_RO(instance_count);
 677
 678static ssize_t expensive_show(struct device *dev,
 679			      struct device_attribute *attr, char *buf)
 680{
 681	struct wmi_block *wblock = dev_to_wblock(dev);
 682
 683	return sprintf(buf, "%d\n",
 684		       (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
 685}
 686static DEVICE_ATTR_RO(expensive);
 687
 688static struct attribute *wmi_attrs[] = {
 689	&dev_attr_modalias.attr,
 690	&dev_attr_guid.attr,
 691	&dev_attr_instance_count.attr,
 692	&dev_attr_expensive.attr,
 693	NULL,
 694};
 695ATTRIBUTE_GROUPS(wmi);
 696
 697static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
 698			      char *buf)
 699{
 700	struct wmi_block *wblock = dev_to_wblock(dev);
 701
 702	return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
 703}
 704static DEVICE_ATTR_RO(notify_id);
 705
 706static struct attribute *wmi_event_attrs[] = {
 707	&dev_attr_notify_id.attr,
 708	NULL,
 709};
 710ATTRIBUTE_GROUPS(wmi_event);
 711
 712static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
 713			      char *buf)
 714{
 715	struct wmi_block *wblock = dev_to_wblock(dev);
 716
 717	return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
 718		       wblock->gblock.object_id[1]);
 719}
 720static DEVICE_ATTR_RO(object_id);
 721
 722static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
 723			    char *buf)
 724{
 725	struct wmi_device *wdev = dev_to_wdev(dev);
 726
 727	return sprintf(buf, "%d\n", (int)wdev->setable);
 728}
 729static DEVICE_ATTR_RO(setable);
 730
 731static struct attribute *wmi_data_attrs[] = {
 732	&dev_attr_object_id.attr,
 733	&dev_attr_setable.attr,
 734	NULL,
 735};
 736ATTRIBUTE_GROUPS(wmi_data);
 737
 738static struct attribute *wmi_method_attrs[] = {
 739	&dev_attr_object_id.attr,
 740	NULL,
 741};
 742ATTRIBUTE_GROUPS(wmi_method);
 743
 744static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 745{
 746	struct wmi_block *wblock = dev_to_wblock(dev);
 747
 748	if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
 749		return -ENOMEM;
 750
 751	if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
 
 752		return -ENOMEM;
 753
 754	return 0;
 755}
 756
 757static void wmi_dev_release(struct device *dev)
 758{
 759	struct wmi_block *wblock = dev_to_wblock(dev);
 760
 761	kfree(wblock);
 762}
 763
 764static int wmi_dev_match(struct device *dev, struct device_driver *driver)
 765{
 766	struct wmi_driver *wmi_driver =
 767		container_of(driver, struct wmi_driver, driver);
 768	struct wmi_block *wblock = dev_to_wblock(dev);
 769	const struct wmi_device_id *id = wmi_driver->id_table;
 770
 771	while (id->guid_string) {
 772		uuid_le driver_guid;
 773
 774		if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid)))
 775			continue;
 776		if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
 777			return 1;
 778
 779		id++;
 780	}
 781
 782	return 0;
 783}
 784static int wmi_char_open(struct inode *inode, struct file *filp)
 785{
 786	const char *driver_name = filp->f_path.dentry->d_iname;
 787	struct wmi_block *wblock = NULL;
 788	struct wmi_block *next = NULL;
 789
 790	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
 791		if (!wblock->dev.dev.driver)
 792			continue;
 793		if (strcmp(driver_name, wblock->dev.dev.driver->name) == 0) {
 794			filp->private_data = wblock;
 795			break;
 796		}
 797	}
 798
 799	if (!filp->private_data)
 800		return -ENODEV;
 801
 802	return nonseekable_open(inode, filp);
 803}
 804
 805static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
 806	size_t length, loff_t *offset)
 807{
 808	struct wmi_block *wblock = filp->private_data;
 809
 810	return simple_read_from_buffer(buffer, length, offset,
 811				       &wblock->req_buf_size,
 812				       sizeof(wblock->req_buf_size));
 813}
 814
 815static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 816{
 817	struct wmi_ioctl_buffer __user *input =
 818		(struct wmi_ioctl_buffer __user *) arg;
 819	struct wmi_block *wblock = filp->private_data;
 820	struct wmi_ioctl_buffer *buf = NULL;
 821	struct wmi_driver *wdriver = NULL;
 822	int ret;
 823
 824	if (_IOC_TYPE(cmd) != WMI_IOC)
 825		return -ENOTTY;
 826
 827	/* make sure we're not calling a higher instance than exists*/
 828	if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
 829		return -EINVAL;
 830
 831	mutex_lock(&wblock->char_mutex);
 832	buf = wblock->handler_data;
 833	if (get_user(buf->length, &input->length)) {
 834		dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
 835		ret = -EFAULT;
 836		goto out_ioctl;
 837	}
 838	/* if it's too small, abort */
 839	if (buf->length < wblock->req_buf_size) {
 840		dev_err(&wblock->dev.dev,
 841			"Buffer %lld too small, need at least %lld\n",
 842			buf->length, wblock->req_buf_size);
 843		ret = -EINVAL;
 844		goto out_ioctl;
 845	}
 846	/* if it's too big, warn, driver will only use what is needed */
 847	if (buf->length > wblock->req_buf_size)
 848		dev_warn(&wblock->dev.dev,
 849			"Buffer %lld is bigger than required %lld\n",
 850			buf->length, wblock->req_buf_size);
 851
 852	/* copy the structure from userspace */
 853	if (copy_from_user(buf, input, wblock->req_buf_size)) {
 854		dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
 855			wblock->req_buf_size);
 856		ret = -EFAULT;
 857		goto out_ioctl;
 858	}
 859
 860	/* let the driver do any filtering and do the call */
 861	wdriver = container_of(wblock->dev.dev.driver,
 862			       struct wmi_driver, driver);
 863	if (!try_module_get(wdriver->driver.owner)) {
 864		ret = -EBUSY;
 865		goto out_ioctl;
 866	}
 867	ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
 868	module_put(wdriver->driver.owner);
 869	if (ret)
 870		goto out_ioctl;
 871
 872	/* return the result (only up to our internal buffer size) */
 873	if (copy_to_user(input, buf, wblock->req_buf_size)) {
 874		dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
 875			wblock->req_buf_size);
 876		ret = -EFAULT;
 877	}
 878
 879out_ioctl:
 880	mutex_unlock(&wblock->char_mutex);
 881	return ret;
 882}
 883
 884static const struct file_operations wmi_fops = {
 885	.owner		= THIS_MODULE,
 886	.read		= wmi_char_read,
 887	.open		= wmi_char_open,
 888	.unlocked_ioctl	= wmi_ioctl,
 889	.compat_ioctl	= wmi_ioctl,
 890};
 891
 892static int wmi_dev_probe(struct device *dev)
 893{
 894	struct wmi_block *wblock = dev_to_wblock(dev);
 895	struct wmi_driver *wdriver =
 896		container_of(dev->driver, struct wmi_driver, driver);
 897	int ret = 0;
 898	int count;
 899	char *buf;
 900
 901	if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
 902		dev_warn(dev, "failed to enable device -- probing anyway\n");
 903
 904	if (wdriver->probe) {
 905		ret = wdriver->probe(dev_to_wdev(dev));
 906		if (ret != 0)
 907			goto probe_failure;
 908	}
 909
 910	/* driver wants a character device made */
 911	if (wdriver->filter_callback) {
 912		/* check that required buffer size declared by driver or MOF */
 913		if (!wblock->req_buf_size) {
 914			dev_err(&wblock->dev.dev,
 915				"Required buffer size not set\n");
 916			ret = -EINVAL;
 917			goto probe_failure;
 918		}
 919
 920		count = get_order(wblock->req_buf_size);
 921		wblock->handler_data = (void *)__get_free_pages(GFP_KERNEL,
 922								count);
 923		if (!wblock->handler_data) {
 924			ret = -ENOMEM;
 925			goto probe_failure;
 926		}
 927
 928		buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
 929		if (!buf) {
 930			ret = -ENOMEM;
 931			goto probe_string_failure;
 932		}
 933		wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
 934		wblock->char_dev.name = buf;
 935		wblock->char_dev.fops = &wmi_fops;
 936		wblock->char_dev.mode = 0444;
 937		ret = misc_register(&wblock->char_dev);
 938		if (ret) {
 939			dev_warn(dev, "failed to register char dev: %d\n", ret);
 940			ret = -ENOMEM;
 941			goto probe_misc_failure;
 942		}
 943	}
 944
 945	return 0;
 946
 947probe_misc_failure:
 948	kfree(buf);
 949probe_string_failure:
 950	kfree(wblock->handler_data);
 951probe_failure:
 952	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
 953		dev_warn(dev, "failed to disable device\n");
 954	return ret;
 955}
 956
 957static int wmi_dev_remove(struct device *dev)
 958{
 959	struct wmi_block *wblock = dev_to_wblock(dev);
 960	struct wmi_driver *wdriver =
 961		container_of(dev->driver, struct wmi_driver, driver);
 962	int ret = 0;
 963
 964	if (wdriver->filter_callback) {
 965		misc_deregister(&wblock->char_dev);
 966		kfree(wblock->char_dev.name);
 967		free_pages((unsigned long)wblock->handler_data,
 968			   get_order(wblock->req_buf_size));
 969	}
 970
 971	if (wdriver->remove)
 972		ret = wdriver->remove(dev_to_wdev(dev));
 973
 974	if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
 975		dev_warn(dev, "failed to disable device\n");
 976
 977	return ret;
 978}
 979
 980static struct class wmi_bus_class = {
 981	.name = "wmi_bus",
 982};
 983
 984static struct bus_type wmi_bus_type = {
 985	.name = "wmi",
 986	.dev_groups = wmi_groups,
 987	.match = wmi_dev_match,
 988	.uevent = wmi_dev_uevent,
 989	.probe = wmi_dev_probe,
 990	.remove = wmi_dev_remove,
 991};
 992
 993static struct device_type wmi_type_event = {
 994	.name = "event",
 995	.groups = wmi_event_groups,
 996	.release = wmi_dev_release,
 997};
 998
 999static struct device_type wmi_type_method = {
1000	.name = "method",
1001	.groups = wmi_method_groups,
1002	.release = wmi_dev_release,
1003};
1004
1005static struct device_type wmi_type_data = {
1006	.name = "data",
1007	.groups = wmi_data_groups,
1008	.release = wmi_dev_release,
1009};
1010
1011static int wmi_create_device(struct device *wmi_bus_dev,
1012			     const struct guid_block *gblock,
1013			     struct wmi_block *wblock,
1014			     struct acpi_device *device)
1015{
1016	struct acpi_device_info *info;
1017	char method[5];
1018	int result;
1019
1020	if (gblock->flags & ACPI_WMI_EVENT) {
1021		wblock->dev.dev.type = &wmi_type_event;
1022		goto out_init;
1023	}
1024
1025	if (gblock->flags & ACPI_WMI_METHOD) {
1026		wblock->dev.dev.type = &wmi_type_method;
1027		mutex_init(&wblock->char_mutex);
1028		goto out_init;
1029	}
1030
1031	/*
1032	 * Data Block Query Control Method (WQxx by convention) is
1033	 * required per the WMI documentation. If it is not present,
1034	 * we ignore this data block.
1035	 */
1036	strcpy(method, "WQ");
1037	strncat(method, wblock->gblock.object_id, 2);
1038	result = get_subobj_info(device->handle, method, &info);
1039
1040	if (result) {
1041		dev_warn(wmi_bus_dev,
1042			 "%s data block query control method not found\n",
1043			 method);
1044		return result;
1045	}
1046
1047	wblock->dev.dev.type = &wmi_type_data;
1048
1049	/*
1050	 * The Microsoft documentation specifically states:
1051	 *
1052	 *   Data blocks registered with only a single instance
1053	 *   can ignore the parameter.
1054	 *
1055	 * ACPICA will get mad at us if we call the method with the wrong number
1056	 * of arguments, so check what our method expects.  (On some Dell
1057	 * laptops, WQxx may not be a method at all.)
1058	 */
1059	if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
1060		wblock->read_takes_no_args = true;
1061
1062	kfree(info);
1063
1064	strcpy(method, "WS");
1065	strncat(method, wblock->gblock.object_id, 2);
1066	result = get_subobj_info(device->handle, method, NULL);
1067
1068	if (result == 0)
1069		wblock->dev.setable = true;
1070
1071 out_init:
1072	wblock->dev.dev.bus = &wmi_bus_type;
1073	wblock->dev.dev.parent = wmi_bus_dev;
1074
1075	dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
1076
1077	device_initialize(&wblock->dev.dev);
1078
1079	return 0;
1080}
1081
1082static void wmi_free_devices(struct acpi_device *device)
1083{
1084	struct wmi_block *wblock, *next;
1085
1086	/* Delete devices for all the GUIDs */
1087	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1088		if (wblock->acpi_device == device) {
1089			list_del(&wblock->list);
1090			device_unregister(&wblock->dev.dev);
1091		}
1092	}
1093}
1094
1095static bool guid_already_parsed(struct acpi_device *device,
1096				const u8 *guid)
1097{
1098	struct wmi_block *wblock;
1099
1100	list_for_each_entry(wblock, &wmi_block_list, list) {
1101		if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
1102			/*
1103			 * Because we historically didn't track the relationship
1104			 * between GUIDs and ACPI nodes, we don't know whether
1105			 * we need to suppress GUIDs that are unique on a
1106			 * given node but duplicated across nodes.
1107			 */
1108			dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
1109				 guid, dev_name(&wblock->acpi_device->dev));
1110			return true;
1111		}
1112	}
1113
1114	return false;
1115}
1116
1117/*
1118 * Parse the _WDG method for the GUID data blocks
1119 */
1120static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
1121{
1122	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
 
1123	const struct guid_block *gblock;
1124	struct wmi_block *wblock, *next;
1125	union acpi_object *obj;
1126	acpi_status status;
1127	int retval = 0;
1128	u32 i, total;
1129
1130	status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
1131	if (ACPI_FAILURE(status))
1132		return -ENXIO;
1133
1134	obj = (union acpi_object *) out.pointer;
1135	if (!obj)
1136		return -ENXIO;
1137
1138	if (obj->type != ACPI_TYPE_BUFFER) {
1139		retval = -ENXIO;
1140		goto out_free_pointer;
1141	}
1142
1143	gblock = (const struct guid_block *)obj->buffer.pointer;
1144	total = obj->buffer.length / sizeof(struct guid_block);
1145
1146	for (i = 0; i < total; i++) {
1147		if (debug_dump_wdg)
1148			wmi_dump_wdg(&gblock[i]);
1149
1150		/*
1151		 * Some WMI devices, like those for nVidia hooks, have a
1152		 * duplicate GUID. It's not clear what we should do in this
1153		 * case yet, so for now, we'll just ignore the duplicate
1154		 * for device creation.
1155		 */
1156		if (guid_already_parsed(device, gblock[i].guid))
1157			continue;
1158
1159		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
1160		if (!wblock) {
1161			retval = -ENOMEM;
1162			break;
1163		}
1164
1165		wblock->acpi_device = device;
1166		wblock->gblock = gblock[i];
1167
1168		retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1169		if (retval) {
1170			kfree(wblock);
1171			continue;
 
 
 
 
 
 
 
 
1172		}
1173
1174		list_add_tail(&wblock->list, &wmi_block_list);
1175
1176		if (debug_event) {
1177			wblock->handler = wmi_notify_debug;
1178			wmi_method_enable(wblock, 1);
1179		}
1180	}
1181
1182	/*
1183	 * Now that all of the devices are created, add them to the
1184	 * device tree and probe subdrivers.
1185	 */
1186	list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1187		if (wblock->acpi_device != device)
1188			continue;
1189
1190		retval = device_add(&wblock->dev.dev);
1191		if (retval) {
1192			dev_err(wmi_bus_dev, "failed to register %pUL\n",
1193				wblock->gblock.guid);
1194			if (debug_event)
1195				wmi_method_enable(wblock, 0);
1196			list_del(&wblock->list);
1197			put_device(&wblock->dev.dev);
1198		}
1199	}
1200
1201out_free_pointer:
1202	kfree(out.pointer);
 
1203	return retval;
1204}
1205
1206/*
1207 * WMI can have EmbeddedControl access regions. In which case, we just want to
1208 * hand these off to the EC driver.
1209 */
1210static acpi_status
1211acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1212		      u32 bits, u64 *value,
1213		      void *handler_context, void *region_context)
1214{
1215	int result = 0, i = 0;
1216	u8 temp = 0;
1217
1218	if ((address > 0xFF) || !value)
1219		return AE_BAD_PARAMETER;
1220
1221	if (function != ACPI_READ && function != ACPI_WRITE)
1222		return AE_BAD_PARAMETER;
1223
1224	if (bits != 8)
1225		return AE_BAD_PARAMETER;
1226
1227	if (function == ACPI_READ) {
1228		result = ec_read(address, &temp);
1229		(*value) |= ((u64)temp) << i;
1230	} else {
1231		temp = 0xff & ((*value) >> i);
1232		result = ec_write(address, temp);
1233	}
1234
1235	switch (result) {
1236	case -EINVAL:
1237		return AE_BAD_PARAMETER;
1238		break;
1239	case -ENODEV:
1240		return AE_NOT_FOUND;
1241		break;
1242	case -ETIME:
1243		return AE_TIME;
1244		break;
1245	default:
1246		return AE_OK;
1247	}
1248}
1249
1250static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1251				    void *context)
1252{
1253	struct guid_block *block;
1254	struct wmi_block *wblock;
1255	bool found_it = false;
 
1256
1257	list_for_each_entry(wblock, &wmi_block_list, list) {
 
1258		block = &wblock->gblock;
1259
1260		if (wblock->acpi_device->handle == handle &&
1261		    (block->flags & ACPI_WMI_EVENT) &&
1262		    (block->notify_id == event))
1263		{
1264			found_it = true;
 
 
 
 
 
 
 
1265			break;
1266		}
1267	}
1268
1269	if (!found_it)
1270		return;
1271
1272	/* If a driver is bound, then notify the driver. */
1273	if (wblock->dev.dev.driver) {
1274		struct wmi_driver *driver;
1275		struct acpi_object_list input;
1276		union acpi_object params[1];
1277		struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1278		acpi_status status;
1279
1280		driver = container_of(wblock->dev.dev.driver,
1281				      struct wmi_driver, driver);
1282
1283		input.count = 1;
1284		input.pointer = params;
1285		params[0].type = ACPI_TYPE_INTEGER;
1286		params[0].integer.value = event;
1287
1288		status = acpi_evaluate_object(wblock->acpi_device->handle,
1289					      "_WED", &input, &evdata);
1290		if (ACPI_FAILURE(status)) {
1291			dev_warn(&wblock->dev.dev,
1292				 "failed to get event data\n");
1293			return;
1294		}
1295
1296		if (driver->notify)
1297			driver->notify(&wblock->dev,
1298				       (union acpi_object *)evdata.pointer);
1299
1300		kfree(evdata.pointer);
1301	} else if (wblock->handler) {
1302		/* Legacy handler */
1303		wblock->handler(event, wblock->handler_data);
1304	}
1305
1306	if (debug_event) {
1307		pr_info("DEBUG Event GUID: %pUL\n",
1308			wblock->gblock.guid);
1309	}
1310
1311	acpi_bus_generate_netlink_event(
1312		wblock->acpi_device->pnp.device_class,
1313		dev_name(&wblock->dev.dev),
1314		event, 0);
1315
1316}
1317
1318static int acpi_wmi_remove(struct platform_device *device)
1319{
1320	struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1321
1322	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1323				   acpi_wmi_notify_handler);
1324	acpi_remove_address_space_handler(acpi_device->handle,
1325				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1326	wmi_free_devices(acpi_device);
1327	device_destroy(&wmi_bus_class, MKDEV(0, 0));
1328
1329	return 0;
1330}
1331
1332static int acpi_wmi_probe(struct platform_device *device)
1333{
1334	struct acpi_device *acpi_device;
1335	struct device *wmi_bus_dev;
1336	acpi_status status;
1337	int error;
1338
1339	acpi_device = ACPI_COMPANION(&device->dev);
1340	if (!acpi_device) {
1341		dev_err(&device->dev, "ACPI companion is missing\n");
1342		return -ENODEV;
1343	}
1344
1345	status = acpi_install_address_space_handler(acpi_device->handle,
1346						    ACPI_ADR_SPACE_EC,
1347						    &acpi_wmi_ec_space_handler,
1348						    NULL, NULL);
1349	if (ACPI_FAILURE(status)) {
1350		dev_err(&device->dev, "Error installing EC region handler\n");
1351		return -ENODEV;
1352	}
1353
1354	status = acpi_install_notify_handler(acpi_device->handle,
1355					     ACPI_DEVICE_NOTIFY,
1356					     acpi_wmi_notify_handler,
1357					     NULL);
1358	if (ACPI_FAILURE(status)) {
1359		dev_err(&device->dev, "Error installing notify handler\n");
1360		error = -ENODEV;
1361		goto err_remove_ec_handler;
1362	}
1363
1364	wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1365				    NULL, "wmi_bus-%s", dev_name(&device->dev));
1366	if (IS_ERR(wmi_bus_dev)) {
1367		error = PTR_ERR(wmi_bus_dev);
1368		goto err_remove_notify_handler;
1369	}
1370	dev_set_drvdata(&device->dev, wmi_bus_dev);
1371
1372	error = parse_wdg(wmi_bus_dev, acpi_device);
1373	if (error) {
 
 
 
1374		pr_err("Failed to parse WDG method\n");
1375		goto err_remove_busdev;
1376	}
1377
1378	return 0;
1379
1380err_remove_busdev:
1381	device_destroy(&wmi_bus_class, MKDEV(0, 0));
1382
1383err_remove_notify_handler:
1384	acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1385				   acpi_wmi_notify_handler);
1386
1387err_remove_ec_handler:
1388	acpi_remove_address_space_handler(acpi_device->handle,
1389					  ACPI_ADR_SPACE_EC,
1390					  &acpi_wmi_ec_space_handler);
1391
1392	return error;
1393}
1394
1395int __must_check __wmi_driver_register(struct wmi_driver *driver,
1396				       struct module *owner)
1397{
1398	driver->driver.owner = owner;
1399	driver->driver.bus = &wmi_bus_type;
1400
1401	return driver_register(&driver->driver);
1402}
1403EXPORT_SYMBOL(__wmi_driver_register);
1404
1405void wmi_driver_unregister(struct wmi_driver *driver)
1406{
1407	driver_unregister(&driver->driver);
1408}
1409EXPORT_SYMBOL(wmi_driver_unregister);
1410
1411static int __init acpi_wmi_init(void)
1412{
1413	int error;
1414
1415	if (acpi_disabled)
1416		return -ENODEV;
1417
1418	error = class_register(&wmi_bus_class);
1419	if (error)
1420		return error;
1421
1422	error = bus_register(&wmi_bus_type);
1423	if (error)
1424		goto err_unreg_class;
1425
1426	error = platform_driver_register(&acpi_wmi_driver);
1427	if (error) {
1428		pr_err("Error loading mapper\n");
1429		goto err_unreg_bus;
 
1430	}
1431
 
1432	return 0;
1433
1434err_unreg_bus:
1435	bus_unregister(&wmi_bus_type);
1436
1437err_unreg_class:
1438	class_unregister(&wmi_bus_class);
1439
1440	return error;
1441}
1442
1443static void __exit acpi_wmi_exit(void)
1444{
1445	platform_driver_unregister(&acpi_wmi_driver);
1446	bus_unregister(&wmi_bus_type);
1447	class_unregister(&wmi_bus_class);
 
1448}
1449
1450subsys_initcall_sync(acpi_wmi_init);
1451module_exit(acpi_wmi_exit);