wmi.c 23 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
/*
 *  ACPI-WMI mapping driver
 *
 *  Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
 *
 *  GUID parsing code from ldm.c is:
 *   Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
 *   Copyright (c) 2001-2007 Anton Altaparmakov
 *   Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

30 31
#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt

32 33 34
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
35
#include <linux/device.h>
36 37
#include <linux/list.h>
#include <linux/acpi.h>
38
#include <linux/slab.h>
39 40 41 42 43 44 45 46 47 48 49
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

ACPI_MODULE_NAME("wmi");
MODULE_AUTHOR("Carlos Corbacho");
MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
MODULE_LICENSE("GPL");

#define ACPI_WMI_CLASS "wmi"

static DEFINE_MUTEX(wmi_data_lock);
50
static LIST_HEAD(wmi_block_list);
51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70

struct guid_block {
	char guid[16];
	union {
		char object_id[2];
		struct {
			unsigned char notify_id;
			unsigned char reserved;
		};
	};
	u8 instance_count;
	u8 flags;
};

struct wmi_block {
	struct list_head list;
	struct guid_block gblock;
	acpi_handle handle;
	wmi_notify_handler handler;
	void *handler_data;
71
	struct device dev;
72 73 74 75 76 77 78 79 80 81 82 83
};


/*
 * If the GUID data block is marked as expensive, we must enable and
 * explicitily disable data collection.
 */
#define ACPI_WMI_EXPENSIVE   0x1
#define ACPI_WMI_METHOD      0x2	/* GUID is a method */
#define ACPI_WMI_STRING      0x4	/* GUID takes & returns a string */
#define ACPI_WMI_EVENT       0x8	/* GUID is an event */

84 85 86 87 88
static int debug_event;
module_param(debug_event, bool, 0444);
MODULE_PARM_DESC(debug_event,
		 "Log WMI Events [0/1]");

89 90 91 92 93
static int debug_dump_wdg;
module_param(debug_dump_wdg, bool, 0444);
MODULE_PARM_DESC(debug_dump_wdg,
		 "Dump available WMI interfaces [0/1]");

94 95
static int acpi_wmi_remove(struct acpi_device *device, int type);
static int acpi_wmi_add(struct acpi_device *device);
96
static void acpi_wmi_notify(struct acpi_device *device, u32 event);
97 98 99 100 101 102 103 104 105 106 107 108 109 110 111

static const struct acpi_device_id wmi_device_ids[] = {
	{"PNP0C14", 0},
	{"pnp0c14", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, wmi_device_ids);

static struct acpi_driver acpi_wmi_driver = {
	.name = "wmi",
	.class = ACPI_WMI_CLASS,
	.ids = wmi_device_ids,
	.ops = {
		.add = acpi_wmi_add,
		.remove = acpi_wmi_remove,
112
		.notify = acpi_wmi_notify,
113
	},
114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131
};

/*
 * GUID parsing functions
 */

/**
 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
 * @src:  Pointer to at least 2 characters to convert.
 *
 * Convert a two character ASCII hex string to a number.
 *
 * Return:  0-255  Success, the byte was parsed correctly
 *          -1     Error, an invalid character was supplied
 */
static int wmi_parse_hexbyte(const u8 *src)
{
	int h;
132
	int value;
133 134

	/* high part */
135 136
	h = value = hex_to_bin(src[0]);
	if (value < 0)
137 138 139
		return -1;

	/* low part */
140 141 142
	value = hex_to_bin(src[1]);
	if (value >= 0)
		return (h << 4) | value;
143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198
	return -1;
}

/**
 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
 * @src:   Memory block holding binary GUID (16 bytes)
 * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
 *
 * Byte swap a binary GUID to match it's real GUID value
 */
static void wmi_swap_bytes(u8 *src, u8 *dest)
{
	int i;

	for (i = 0; i <= 3; i++)
		memcpy(dest + i, src + (3 - i), 1);

	for (i = 0; i <= 1; i++)
		memcpy(dest + 4 + i, src + (5 - i), 1);

	for (i = 0; i <= 1; i++)
		memcpy(dest + 6 + i, src + (7 - i), 1);

	memcpy(dest + 8, src + 8, 8);
}

/**
 * wmi_parse_guid - Convert GUID from ASCII to binary
 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 * @dest:  Memory block to hold binary GUID (16 bytes)
 *
 * N.B. The GUID need not be NULL terminated.
 *
 * Return:  'true'   @dest contains binary GUID
 *          'false'  @dest contents are undefined
 */
static bool wmi_parse_guid(const u8 *src, u8 *dest)
{
	static const int size[] = { 4, 2, 2, 2, 6 };
	int i, j, v;

	if (src[8]  != '-' || src[13] != '-' ||
		src[18] != '-' || src[23] != '-')
		return false;

	for (j = 0; j < 5; j++, src++) {
		for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
			v = wmi_parse_hexbyte(src);
			if (v < 0)
				return false;
		}
	}

	return true;
}

199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222
/*
 * Convert a raw GUID to the ACII string representation
 */
static int wmi_gtoa(const char *in, char *out)
{
	int i;

	for (i = 3; i >= 0; i--)
		out += sprintf(out, "%02X", in[i] & 0xFF);

	out += sprintf(out, "-");
	out += sprintf(out, "%02X", in[5] & 0xFF);
	out += sprintf(out, "%02X", in[4] & 0xFF);
	out += sprintf(out, "-");
	out += sprintf(out, "%02X", in[7] & 0xFF);
	out += sprintf(out, "%02X", in[6] & 0xFF);
	out += sprintf(out, "-");
	out += sprintf(out, "%02X", in[8] & 0xFF);
	out += sprintf(out, "%02X", in[9] & 0xFF);
	out += sprintf(out, "-");

	for (i = 10; i <= 15; i++)
		out += sprintf(out, "%02X", in[i] & 0xFF);

223
	*out = '\0';
224 225 226
	return 0;
}

227 228 229 230 231 232 233 234 235 236
static bool find_guid(const char *guid_string, struct wmi_block **out)
{
	char tmp[16], guid_input[16];
	struct wmi_block *wblock;
	struct guid_block *block;
	struct list_head *p;

	wmi_parse_guid(guid_string, tmp);
	wmi_swap_bytes(tmp, guid_input);

237
	list_for_each(p, &wmi_block_list) {
238 239 240 241 242 243 244 245 246 247 248 249
		wblock = list_entry(p, struct wmi_block, list);
		block = &wblock->gblock;

		if (memcmp(block->guid, guid_input, 16) == 0) {
			if (out)
				*out = wblock;
			return 1;
		}
	}
	return 0;
}

250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278
static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
{
	struct guid_block *block = NULL;
	char method[5];
	struct acpi_object_list input;
	union acpi_object params[1];
	acpi_status status;
	acpi_handle handle;

	block = &wblock->gblock;
	handle = wblock->handle;

	if (!block)
		return AE_NOT_EXIST;

	input.count = 1;
	input.pointer = params;
	params[0].type = ACPI_TYPE_INTEGER;
	params[0].integer.value = enable;

	snprintf(method, 5, "WE%02X", block->notify_id);
	status = acpi_evaluate_object(handle, method, &input, NULL);

	if (status != AE_OK && status != AE_NOT_FOUND)
		return status;
	else
		return AE_OK;
}

279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300
/*
 * Exported WMI functions
 */
/**
 * wmi_evaluate_method - Evaluate a WMI method
 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 * @instance: Instance index
 * @method_id: Method ID to call
 * &in: Buffer containing input for the method call
 * &out: Empty buffer to return the method results
 *
 * Call an ACPI-WMI method
 */
acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
{
	struct guid_block *block = NULL;
	struct wmi_block *wblock = NULL;
	acpi_handle handle;
	acpi_status status;
	struct acpi_object_list input;
	union acpi_object params[3];
301
	char method[5] = "WM";
302 303

	if (!find_guid(guid_string, &wblock))
304
		return AE_ERROR;
305 306 307 308

	block = &wblock->gblock;
	handle = wblock->handle;

Al Viro's avatar
Al Viro committed
309
	if (!(block->flags & ACPI_WMI_METHOD))
310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354
		return AE_BAD_DATA;

	if (block->instance_count < instance)
		return AE_BAD_PARAMETER;

	input.count = 2;
	input.pointer = params;
	params[0].type = ACPI_TYPE_INTEGER;
	params[0].integer.value = instance;
	params[1].type = ACPI_TYPE_INTEGER;
	params[1].integer.value = method_id;

	if (in) {
		input.count = 3;

		if (block->flags & ACPI_WMI_STRING) {
			params[2].type = ACPI_TYPE_STRING;
		} else {
			params[2].type = ACPI_TYPE_BUFFER;
		}
		params[2].buffer.length = in->length;
		params[2].buffer.pointer = in->pointer;
	}

	strncat(method, block->object_id, 2);

	status = acpi_evaluate_object(handle, method, &input, out);

	return status;
}
EXPORT_SYMBOL_GPL(wmi_evaluate_method);

/**
 * wmi_query_block - Return contents of a WMI block
 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 * @instance: Instance index
 * &out: Empty buffer to return the contents of the data block to
 *
 * Return the contents of an ACPI-WMI data block to a buffer
 */
acpi_status wmi_query_block(const char *guid_string, u8 instance,
struct acpi_buffer *out)
{
	struct guid_block *block = NULL;
	struct wmi_block *wblock = NULL;
355
	acpi_handle handle, wc_handle;
356 357 358
	acpi_status status, wc_status = AE_ERROR;
	struct acpi_object_list input, wc_input;
	union acpi_object wc_params[1], wq_params[1];
359 360
	char method[5];
	char wc_method[5] = "WC";
361 362 363 364 365

	if (!guid_string || !out)
		return AE_BAD_PARAMETER;

	if (!find_guid(guid_string, &wblock))
366
		return AE_ERROR;
367 368 369 370 371 372 373 374 375

	block = &wblock->gblock;
	handle = wblock->handle;

	if (block->instance_count < instance)
		return AE_BAD_PARAMETER;

	/* Check GUID is a data block */
	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
376
		return AE_ERROR;
377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399

	input.count = 1;
	input.pointer = wq_params;
	wq_params[0].type = ACPI_TYPE_INTEGER;
	wq_params[0].integer.value = instance;

	/*
	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
	 * enable collection.
	 */
	if (block->flags & ACPI_WMI_EXPENSIVE) {
		wc_input.count = 1;
		wc_input.pointer = wc_params;
		wc_params[0].type = ACPI_TYPE_INTEGER;
		wc_params[0].integer.value = 1;

		strncat(wc_method, block->object_id, 2);

		/*
		 * Some GUIDs break the specification by declaring themselves
		 * expensive, but have no corresponding WCxx method. So we
		 * should not fail if this happens.
		 */
400 401 402 403
		wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
		if (ACPI_SUCCESS(wc_status))
			wc_status = acpi_evaluate_object(handle, wc_method,
				&wc_input, NULL);
404 405 406 407 408
	}

	strcpy(method, "WQ");
	strncat(method, block->object_id, 2);

409
	status = acpi_evaluate_object(handle, method, &input, out);
410 411 412 413 414

	/*
	 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
	 * the WQxx method failed - we should disable collection anyway.
	 */
415
	if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440
		wc_params[0].integer.value = 0;
		status = acpi_evaluate_object(handle,
		wc_method, &wc_input, NULL);
	}

	return status;
}
EXPORT_SYMBOL_GPL(wmi_query_block);

/**
 * wmi_set_block - Write to a WMI block
 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 * @instance: Instance index
 * &in: Buffer containing new values for the data block
 *
 * Write the contents of the input buffer to an ACPI-WMI data block
 */
acpi_status wmi_set_block(const char *guid_string, u8 instance,
const struct acpi_buffer *in)
{
	struct guid_block *block = NULL;
	struct wmi_block *wblock = NULL;
	acpi_handle handle;
	struct acpi_object_list input;
	union acpi_object params[2];
441
	char method[5] = "WS";
442 443 444 445 446

	if (!guid_string || !in)
		return AE_BAD_DATA;

	if (!find_guid(guid_string, &wblock))
447
		return AE_ERROR;
448 449 450 451 452 453 454 455 456

	block = &wblock->gblock;
	handle = wblock->handle;

	if (block->instance_count < instance)
		return AE_BAD_PARAMETER;

	/* Check GUID is a data block */
	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
457
		return AE_ERROR;
458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477

	input.count = 2;
	input.pointer = params;
	params[0].type = ACPI_TYPE_INTEGER;
	params[0].integer.value = instance;

	if (block->flags & ACPI_WMI_STRING) {
		params[1].type = ACPI_TYPE_STRING;
	} else {
		params[1].type = ACPI_TYPE_BUFFER;
	}
	params[1].buffer.length = in->length;
	params[1].buffer.pointer = in->pointer;

	strncat(method, block->object_id, 2);

	return acpi_evaluate_object(handle, method, &input, NULL);
}
EXPORT_SYMBOL_GPL(wmi_set_block);

478
static void wmi_dump_wdg(const struct guid_block *g)
479 480 481 482
{
	char guid_string[37];

	wmi_gtoa(g->guid, guid_string);
483 484 485 486 487 488 489

	pr_info("%s:\n", guid_string);
	pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
	pr_info("\tnotify_id: %02X\n", g->notify_id);
	pr_info("\treserved: %02X\n", g->reserved);
	pr_info("\tinstance_count: %d\n", g->instance_count);
	pr_info("\tflags: %#x ", g->flags);
490 491
	if (g->flags) {
		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

}

504 505 506 507
static void wmi_notify_debug(u32 value, void *context)
{
	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *obj;
508
	acpi_status status;
509

510 511
	status = wmi_get_event_data(value, &response);
	if (status != AE_OK) {
512
		pr_info("bad event status 0x%x\n", status);
513 514
		return;
	}
515 516 517 518 519 520

	obj = (union acpi_object *)response.pointer;

	if (!obj)
		return;

521
	pr_info("DEBUG Event ");
522 523
	switch(obj->type) {
	case ACPI_TYPE_BUFFER:
524
		pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
525 526
		break;
	case ACPI_TYPE_STRING:
527
		pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
528 529
		break;
	case ACPI_TYPE_INTEGER:
530
		pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
531 532
		break;
	case ACPI_TYPE_PACKAGE:
533
		pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
534 535
		break;
	default:
536
		pr_cont("object type 0x%X\n", obj->type);
537
	}
538
	kfree(obj);
539 540
}

541 542 543 544 545 546 547 548 549 550 551
/**
 * wmi_install_notify_handler - Register handler for WMI events
 * @handler: Function to handle notifications
 * @data: Data to be returned to handler when event is fired
 *
 * Register a handler for events sent to the ACPI-WMI mapper device.
 */
acpi_status wmi_install_notify_handler(const char *guid,
wmi_notify_handler handler, void *data)
{
	struct wmi_block *block;
552 553 554
	acpi_status status = AE_NOT_EXIST;
	char tmp[16], guid_input[16];
	struct list_head *p;
555 556 557 558

	if (!guid || !handler)
		return AE_BAD_PARAMETER;

559 560
	wmi_parse_guid(guid, tmp);
	wmi_swap_bytes(tmp, guid_input);
561

562 563 564 565 566 567 568 569
	list_for_each(p, &wmi_block_list) {
		acpi_status wmi_status;
		block = list_entry(p, struct wmi_block, list);

		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
			if (block->handler &&
			    block->handler != wmi_notify_debug)
				return AE_ALREADY_ACQUIRED;
570

571 572
			block->handler = handler;
			block->handler_data = data;
573

574 575 576 577 578 579
			wmi_status = wmi_method_enable(block, 1);
			if ((wmi_status != AE_OK) ||
			    ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
				status = wmi_status;
		}
	}
580 581

	return status;
582 583 584 585 586 587 588 589 590 591 592
}
EXPORT_SYMBOL_GPL(wmi_install_notify_handler);

/**
 * wmi_uninstall_notify_handler - Unregister handler for WMI events
 *
 * Unregister handler for events sent to the ACPI-WMI mapper device.
 */
acpi_status wmi_remove_notify_handler(const char *guid)
{
	struct wmi_block *block;
593 594 595
	acpi_status status = AE_NOT_EXIST;
	char tmp[16], guid_input[16];
	struct list_head *p;
596 597 598 599

	if (!guid)
		return AE_BAD_PARAMETER;

600 601
	wmi_parse_guid(guid, tmp);
	wmi_swap_bytes(tmp, guid_input);
602

603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624
	list_for_each(p, &wmi_block_list) {
		acpi_status wmi_status;
		block = list_entry(p, struct wmi_block, list);

		if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
			if (!block->handler ||
			    block->handler == wmi_notify_debug)
				return AE_NULL_ENTRY;

			if (debug_event) {
				block->handler = wmi_notify_debug;
				status = AE_OK;
			} else {
				wmi_status = wmi_method_enable(block, 0);
				block->handler = NULL;
				block->handler_data = NULL;
				if ((wmi_status != AE_OK) ||
				    ((wmi_status == AE_OK) &&
				     (status == AE_NOT_EXIST)))
					status = wmi_status;
			}
		}
625
	}
626

627
	return status;
628 629 630 631 632 633
}
EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);

/**
 * wmi_get_event_data - Get WMI data associated with an event
 *
634 635
 * @event: Event to find
 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651
 *
 * Returns extra data associated with an event in WMI.
 */
acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
{
	struct acpi_object_list input;
	union acpi_object params[1];
	struct guid_block *gblock;
	struct wmi_block *wblock;
	struct list_head *p;

	input.count = 1;
	input.pointer = params;
	params[0].type = ACPI_TYPE_INTEGER;
	params[0].integer.value = event;

652
	list_for_each(p, &wmi_block_list) {
653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677
		wblock = list_entry(p, struct wmi_block, list);
		gblock = &wblock->gblock;

		if ((gblock->flags & ACPI_WMI_EVENT) &&
			(gblock->notify_id == event))
			return acpi_evaluate_object(wblock->handle, "_WED",
				&input, out);
	}

	return AE_NOT_FOUND;
}
EXPORT_SYMBOL_GPL(wmi_get_event_data);

/**
 * wmi_has_guid - Check if a GUID is available
 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 *
 * Check if a given GUID is defined by _WDG
 */
bool wmi_has_guid(const char *guid_string)
{
	return find_guid(guid_string, NULL);
}
EXPORT_SYMBOL_GPL(wmi_has_guid);

678 679 680
/*
 * sysfs interface
 */
681
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
682 683 684 685 686 687 688 689 690 691 692 693 694
			     char *buf)
{
	char guid_string[37];
	struct wmi_block *wblock;

	wblock = dev_get_drvdata(dev);
	if (!wblock)
		return -ENOMEM;

	wmi_gtoa(wblock->gblock.guid, guid_string);

	return sprintf(buf, "wmi:%s\n", guid_string);
}
695 696 697 698 699

static struct device_attribute wmi_dev_attrs[] = {
	__ATTR_RO(modalias),
	__ATTR_NULL
};
700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724

static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	char guid_string[37];

	struct wmi_block *wblock;

	if (add_uevent_var(env, "MODALIAS="))
		return -ENOMEM;

	wblock = dev_get_drvdata(dev);
	if (!wblock)
		return -ENOMEM;

	wmi_gtoa(wblock->gblock.guid, guid_string);

	strcpy(&env->buf[env->buflen - 1], "wmi:");
	memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
	env->buflen += 40;

	return 0;
}

static void wmi_dev_free(struct device *dev)
{
725 726 727
	struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);

	kfree(wmi_block);
728 729 730 731 732 733
}

static struct class wmi_class = {
	.name = "wmi",
	.dev_release = wmi_dev_free,
	.dev_uevent = wmi_dev_uevent,
734
	.dev_attrs = wmi_dev_attrs,
735 736
};

737 738
static int wmi_create_device(const struct guid_block *gblock,
			     struct wmi_block *wblock, acpi_handle handle)
739
{
740
	char guid_string[37];
741

742
	wblock->dev.class = &wmi_class;
743

744 745
	wmi_gtoa(gblock->guid, guid_string);
	dev_set_name(&wblock->dev, guid_string);
746

747
	dev_set_drvdata(&wblock->dev, wblock);
748

749
	return device_register(&wblock->dev);
750 751
}

752
static 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)
758 759
		if (wblock->dev.class)
			device_unregister(&wblock->dev);
760 761
}

762 763 764 765
static bool guid_already_parsed(const char *guid_string)
{
	struct wmi_block *wblock;

766
	list_for_each_entry(wblock, &wmi_block_list, list)
767
		if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
768 769
			return true;

770
	return false;
771 772
}

773 774 775
/*
 * Parse the _WDG method for the GUID data blocks
 */
776
static acpi_status parse_wdg(acpi_handle handle)
777 778 779
{
	struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
	union acpi_object *obj;
780
	const struct guid_block *gblock;
781 782
	struct wmi_block *wblock;
	acpi_status status;
783
	int retval;
784 785 786 787
	u32 i, total;

	status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
	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;
796 797
		goto out_free_pointer;
	}
798

799
	gblock = (const struct guid_block *)obj->buffer.pointer;
800 801 802
	total = obj->buffer.length / sizeof(struct guid_block);

	for (i = 0; i < total; i++) {
803 804 805 806 807 808 809 810 811 812
		if (debug_dump_wdg)
			wmi_dump_wdg(&gblock[i]);

		wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
		if (!wblock)
			return AE_NO_MEMORY;

		wblock->handle = handle;
		wblock->gblock = gblock[i];

813 814 815
		/*
		  Some WMI devices, like those for nVidia hooks, have a
		  duplicate GUID. It's not clear what we should do in this
816 817
		  case yet, so for now, we'll just ignore the duplicate
		  for device creation.
818
		*/
819 820 821 822
		if (!guid_already_parsed(gblock[i].guid)) {
			retval = wmi_create_device(&gblock[i], wblock, handle);
			if (retval) {
				wmi_free_devices();
823
				goto out_free_pointer;
824
			}
825
		}
826

827
		list_add_tail(&wblock->list, &wmi_block_list);
828

829 830
		if (debug_event) {
			wblock->handler = wmi_notify_debug;
831
			wmi_method_enable(wblock, 1);
832
		}
833 834
	}

835 836
	retval = 0;

Axel Lin's avatar
Axel Lin committed
837 838
out_free_pointer:
	kfree(out.pointer);
839

840
	return retval;
841 842 843 844 845 846 847 848
}

/*
 * WMI can have EmbeddedControl access regions. In which case, we just want to
 * hand these off to the EC driver.
 */
static acpi_status
acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
Lin Ming's avatar
Lin Ming committed
849
		      u32 bits, u64 *value,
850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865
		      void *handler_context, void *region_context)
{
	int result = 0, i = 0;
	u8 temp = 0;

	if ((address > 0xFF) || !value)
		return AE_BAD_PARAMETER;

	if (function != ACPI_READ && function != ACPI_WRITE)
		return AE_BAD_PARAMETER;

	if (bits != 8)
		return AE_BAD_PARAMETER;

	if (function == ACPI_READ) {
		result = ec_read(address, &temp);
Lin Ming's avatar
Lin Ming committed
866
		(*value) |= ((u64)temp) << i;
867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886
	} else {
		temp = 0xff & ((*value) >> i);
		result = ec_write(address, temp);
	}

	switch (result) {
	case -EINVAL:
		return AE_BAD_PARAMETER;
		break;
	case -ENODEV:
		return AE_NOT_FOUND;
		break;
	case -ETIME:
		return AE_TIME;
		break;
	default:
		return AE_OK;
	}
}

887
static void acpi_wmi_notify(struct acpi_device *device, u32 event)
888 889 890 891
{
	struct guid_block *block;
	struct wmi_block *wblock;
	struct list_head *p;
892
	char guid_string[37];
893

894
	list_for_each(p, &wmi_block_list) {
895 896 897 898 899 900 901
		wblock = list_entry(p, struct wmi_block, list);
		block = &wblock->gblock;

		if ((block->flags & ACPI_WMI_EVENT) &&
			(block->notify_id == event)) {
			if (wblock->handler)
				wblock->handler(event, wblock->handler_data);
902 903
			if (debug_event) {
				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),
909 910 911 912 913 914 915 916 917 918
				event, 0);
			break;
		}
	}
}

static int acpi_wmi_remove(struct acpi_device *device, int type)
{
	acpi_remove_address_space_handler(device->handle,
				ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
919
	wmi_free_devices();
920 921 922 923

	return 0;
}

924
static int acpi_wmi_add(struct acpi_device *device)
925 926
{
	acpi_status status;
927
	int error;
928 929 930 931 932

	status = acpi_install_address_space_handler(device->handle,
						    ACPI_ADR_SPACE_EC,
						    &acpi_wmi_ec_space_handler,
						    NULL, NULL);
933
	if (ACPI_FAILURE(status)) {
934
		pr_err("Error installing EC region handler\n");
935
		return -ENODEV;
936
	}
937

938 939
	error = parse_wdg(device->handle);
	if (error) {
940 941 942
		acpi_remove_address_space_handler(device->handle,
						  ACPI_ADR_SPACE_EC,
						  &acpi_wmi_ec_space_handler);
943
		pr_err("Failed to parse WDG method\n");
944
		return error;
945 946
	}

947
	return 0;
948 949 950 951
}

static int __init acpi_wmi_init(void)
{
952
	int error;
953 954 955 956

	if (acpi_disabled)
		return -ENODEV;

957 958 959
	error = class_register(&wmi_class);
	if (error)
		return error;
960

961 962 963 964 965
	error = acpi_bus_register_driver(&acpi_wmi_driver);
	if (error) {
		pr_err("Error loading mapper\n");
		class_unregister(&wmi_class);
		return error;
966 967
	}

968 969
	pr_info("Mapper loaded\n");
	return 0;
970 971 972 973 974
}

static void __exit acpi_wmi_exit(void)
{
	acpi_bus_unregister_driver(&acpi_wmi_driver);
975
	class_unregister(&wmi_class);
976

977
	pr_info("Mapper unloaded\n");
978 979 980 981
}

subsys_initcall(acpi_wmi_init);
module_exit(acpi_wmi_exit);