1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  HID support for Linux
   4 *
   5 *  Copyright (c) 1999 Andreas Gal
   6 *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
   7 *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
   8 *  Copyright (c) 2006-2012 Jiri Kosina
   9 */
  10
  11/*
 
 
 
 
  12 */
  13
  14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16#include <linux/module.h>
  17#include <linux/slab.h>
  18#include <linux/init.h>
  19#include <linux/kernel.h>
  20#include <linux/list.h>
  21#include <linux/mm.h>
  22#include <linux/spinlock.h>
  23#include <asm/unaligned.h>
  24#include <asm/byteorder.h>
  25#include <linux/input.h>
  26#include <linux/wait.h>
  27#include <linux/vmalloc.h>
  28#include <linux/sched.h>
  29#include <linux/semaphore.h>
  30
  31#include <linux/hid.h>
  32#include <linux/hiddev.h>
  33#include <linux/hid-debug.h>
  34#include <linux/hidraw.h>
  35
  36#include "hid-ids.h"
  37
  38/*
  39 * Version Information
  40 */
  41
  42#define DRIVER_DESC "HID core driver"
 
  43
  44int hid_debug = 0;
  45module_param_named(debug, hid_debug, int, 0600);
  46MODULE_PARM_DESC(debug, "toggle HID debugging messages");
  47EXPORT_SYMBOL_GPL(hid_debug);
  48
  49static int hid_ignore_special_drivers = 0;
  50module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
  51MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
  52
  53/*
  54 * Register a new report for a device.
  55 */
  56
  57struct hid_report *hid_register_report(struct hid_device *device,
  58				       unsigned int type, unsigned int id,
  59				       unsigned int application)
  60{
  61	struct hid_report_enum *report_enum = device->report_enum + type;
  62	struct hid_report *report;
  63
  64	if (id >= HID_MAX_IDS)
  65		return NULL;
  66	if (report_enum->report_id_hash[id])
  67		return report_enum->report_id_hash[id];
  68
  69	report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
  70	if (!report)
  71		return NULL;
  72
  73	if (id != 0)
  74		report_enum->numbered = 1;
  75
  76	report->id = id;
  77	report->type = type;
  78	report->size = 0;
  79	report->device = device;
  80	report->application = application;
  81	report_enum->report_id_hash[id] = report;
  82
  83	list_add_tail(&report->list, &report_enum->report_list);
  84
  85	return report;
  86}
  87EXPORT_SYMBOL_GPL(hid_register_report);
  88
  89/*
  90 * Register a new field for this report.
  91 */
  92
  93static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values)
  94{
  95	struct hid_field *field;
  96
  97	if (report->maxfield == HID_MAX_FIELDS) {
  98		hid_err(report->device, "too many fields in report\n");
  99		return NULL;
 100	}
 101
 102	field = kzalloc((sizeof(struct hid_field) +
 103			 usages * sizeof(struct hid_usage) +
 104			 values * sizeof(unsigned)), GFP_KERNEL);
 105	if (!field)
 106		return NULL;
 107
 108	field->index = report->maxfield++;
 109	report->field[field->index] = field;
 110	field->usage = (struct hid_usage *)(field + 1);
 111	field->value = (s32 *)(field->usage + usages);
 112	field->report = report;
 113
 114	return field;
 115}
 116
 117/*
 118 * Open a collection. The type/usage is pushed on the stack.
 119 */
 120
 121static int open_collection(struct hid_parser *parser, unsigned type)
 122{
 123	struct hid_collection *collection;
 124	unsigned usage;
 125	int collection_index;
 126
 127	usage = parser->local.usage[0];
 128
 129	if (parser->collection_stack_ptr == parser->collection_stack_size) {
 130		unsigned int *collection_stack;
 131		unsigned int new_size = parser->collection_stack_size +
 132					HID_COLLECTION_STACK_SIZE;
 133
 134		collection_stack = krealloc(parser->collection_stack,
 135					    new_size * sizeof(unsigned int),
 136					    GFP_KERNEL);
 137		if (!collection_stack)
 138			return -ENOMEM;
 139
 140		parser->collection_stack = collection_stack;
 141		parser->collection_stack_size = new_size;
 142	}
 143
 144	if (parser->device->maxcollection == parser->device->collection_size) {
 145		collection = kmalloc(
 146				array3_size(sizeof(struct hid_collection),
 147					    parser->device->collection_size,
 148					    2),
 149				GFP_KERNEL);
 150		if (collection == NULL) {
 151			hid_err(parser->device, "failed to reallocate collection array\n");
 152			return -ENOMEM;
 153		}
 154		memcpy(collection, parser->device->collection,
 155			sizeof(struct hid_collection) *
 156			parser->device->collection_size);
 157		memset(collection + parser->device->collection_size, 0,
 158			sizeof(struct hid_collection) *
 159			parser->device->collection_size);
 160		kfree(parser->device->collection);
 161		parser->device->collection = collection;
 162		parser->device->collection_size *= 2;
 163	}
 164
 165	parser->collection_stack[parser->collection_stack_ptr++] =
 166		parser->device->maxcollection;
 167
 168	collection_index = parser->device->maxcollection++;
 169	collection = parser->device->collection + collection_index;
 170	collection->type = type;
 171	collection->usage = usage;
 172	collection->level = parser->collection_stack_ptr - 1;
 173	collection->parent_idx = (collection->level == 0) ? -1 :
 174		parser->collection_stack[collection->level - 1];
 175
 176	if (type == HID_COLLECTION_APPLICATION)
 177		parser->device->maxapplication++;
 178
 179	return 0;
 180}
 181
 182/*
 183 * Close a collection.
 184 */
 185
 186static int close_collection(struct hid_parser *parser)
 187{
 188	if (!parser->collection_stack_ptr) {
 189		hid_err(parser->device, "collection stack underflow\n");
 190		return -EINVAL;
 191	}
 192	parser->collection_stack_ptr--;
 193	return 0;
 194}
 195
 196/*
 197 * Climb up the stack, search for the specified collection type
 198 * and return the usage.
 199 */
 200
 201static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
 202{
 203	struct hid_collection *collection = parser->device->collection;
 204	int n;
 205
 206	for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
 207		unsigned index = parser->collection_stack[n];
 208		if (collection[index].type == type)
 209			return collection[index].usage;
 210	}
 211	return 0; /* we know nothing about this usage type */
 212}
 213
 214/*
 215 * Add a usage to the temporary parser table.
 216 */
 217
 218static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
 219{
 220	if (parser->local.usage_index >= HID_MAX_USAGES) {
 221		hid_err(parser->device, "usage index exceeded\n");
 222		return -1;
 223	}
 224	parser->local.usage[parser->local.usage_index] = usage;
 225	parser->local.usage_size[parser->local.usage_index] = size;
 226	parser->local.collection_index[parser->local.usage_index] =
 227		parser->collection_stack_ptr ?
 228		parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
 229	parser->local.usage_index++;
 230	return 0;
 231}
 232
 233/*
 234 * Register a new field for this report.
 235 */
 236
 237static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
 238{
 239	struct hid_report *report;
 240	struct hid_field *field;
 241	unsigned int usages;
 242	unsigned int offset;
 243	unsigned int i;
 244	unsigned int application;
 245
 246	application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
 247
 248	report = hid_register_report(parser->device, report_type,
 249				     parser->global.report_id, application);
 250	if (!report) {
 251		hid_err(parser->device, "hid_register_report failed\n");
 252		return -1;
 253	}
 254
 255	/* Handle both signed and unsigned cases properly */
 256	if ((parser->global.logical_minimum < 0 &&
 257		parser->global.logical_maximum <
 258		parser->global.logical_minimum) ||
 259		(parser->global.logical_minimum >= 0 &&
 260		(__u32)parser->global.logical_maximum <
 261		(__u32)parser->global.logical_minimum)) {
 262		dbg_hid("logical range invalid 0x%x 0x%x\n",
 263			parser->global.logical_minimum,
 264			parser->global.logical_maximum);
 265		return -1;
 266	}
 267
 268	offset = report->size;
 269	report->size += parser->global.report_size * parser->global.report_count;
 270
 271	if (!parser->local.usage_index) /* Ignore padding fields */
 272		return 0;
 273
 274	usages = max_t(unsigned, parser->local.usage_index,
 275				 parser->global.report_count);
 276
 277	field = hid_register_field(report, usages, parser->global.report_count);
 278	if (!field)
 279		return 0;
 280
 281	field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
 282	field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
 283	field->application = application;
 284
 285	for (i = 0; i < usages; i++) {
 286		unsigned j = i;
 287		/* Duplicate the last usage we parsed if we have excess values */
 288		if (i >= parser->local.usage_index)
 289			j = parser->local.usage_index - 1;
 290		field->usage[i].hid = parser->local.usage[j];
 291		field->usage[i].collection_index =
 292			parser->local.collection_index[j];
 293		field->usage[i].usage_index = i;
 294		field->usage[i].resolution_multiplier = 1;
 295	}
 296
 297	field->maxusage = usages;
 298	field->flags = flags;
 299	field->report_offset = offset;
 300	field->report_type = report_type;
 301	field->report_size = parser->global.report_size;
 302	field->report_count = parser->global.report_count;
 303	field->logical_minimum = parser->global.logical_minimum;
 304	field->logical_maximum = parser->global.logical_maximum;
 305	field->physical_minimum = parser->global.physical_minimum;
 306	field->physical_maximum = parser->global.physical_maximum;
 307	field->unit_exponent = parser->global.unit_exponent;
 308	field->unit = parser->global.unit;
 309
 310	return 0;
 311}
 312
 313/*
 314 * Read data value from item.
 315 */
 316
 317static u32 item_udata(struct hid_item *item)
 318{
 319	switch (item->size) {
 320	case 1: return item->data.u8;
 321	case 2: return item->data.u16;
 322	case 4: return item->data.u32;
 323	}
 324	return 0;
 325}
 326
 327static s32 item_sdata(struct hid_item *item)
 328{
 329	switch (item->size) {
 330	case 1: return item->data.s8;
 331	case 2: return item->data.s16;
 332	case 4: return item->data.s32;
 333	}
 334	return 0;
 335}
 336
 337/*
 338 * Process a global item.
 339 */
 340
 341static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 342{
 343	__s32 raw_value;
 344	switch (item->tag) {
 345	case HID_GLOBAL_ITEM_TAG_PUSH:
 346
 347		if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
 348			hid_err(parser->device, "global environment stack overflow\n");
 349			return -1;
 350		}
 351
 352		memcpy(parser->global_stack + parser->global_stack_ptr++,
 353			&parser->global, sizeof(struct hid_global));
 354		return 0;
 355
 356	case HID_GLOBAL_ITEM_TAG_POP:
 357
 358		if (!parser->global_stack_ptr) {
 359			hid_err(parser->device, "global environment stack underflow\n");
 360			return -1;
 361		}
 362
 363		memcpy(&parser->global, parser->global_stack +
 364			--parser->global_stack_ptr, sizeof(struct hid_global));
 365		return 0;
 366
 367	case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
 368		parser->global.usage_page = item_udata(item);
 369		return 0;
 370
 371	case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
 372		parser->global.logical_minimum = item_sdata(item);
 373		return 0;
 374
 375	case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
 376		if (parser->global.logical_minimum < 0)
 377			parser->global.logical_maximum = item_sdata(item);
 378		else
 379			parser->global.logical_maximum = item_udata(item);
 380		return 0;
 381
 382	case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
 383		parser->global.physical_minimum = item_sdata(item);
 384		return 0;
 385
 386	case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
 387		if (parser->global.physical_minimum < 0)
 388			parser->global.physical_maximum = item_sdata(item);
 389		else
 390			parser->global.physical_maximum = item_udata(item);
 391		return 0;
 392
 393	case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
 394		/* Many devices provide unit exponent as a two's complement
 395		 * nibble due to the common misunderstanding of HID
 396		 * specification 1.11, 6.2.2.7 Global Items. Attempt to handle
 397		 * both this and the standard encoding. */
 398		raw_value = item_sdata(item);
 399		if (!(raw_value & 0xfffffff0))
 400			parser->global.unit_exponent = hid_snto32(raw_value, 4);
 401		else
 402			parser->global.unit_exponent = raw_value;
 403		return 0;
 404
 405	case HID_GLOBAL_ITEM_TAG_UNIT:
 406		parser->global.unit = item_udata(item);
 407		return 0;
 408
 409	case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
 410		parser->global.report_size = item_udata(item);
 411		if (parser->global.report_size > 256) {
 412			hid_err(parser->device, "invalid report_size %d\n",
 413					parser->global.report_size);
 414			return -1;
 415		}
 416		return 0;
 417
 418	case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
 419		parser->global.report_count = item_udata(item);
 420		if (parser->global.report_count > HID_MAX_USAGES) {
 421			hid_err(parser->device, "invalid report_count %d\n",
 422					parser->global.report_count);
 423			return -1;
 424		}
 425		return 0;
 426
 427	case HID_GLOBAL_ITEM_TAG_REPORT_ID:
 428		parser->global.report_id = item_udata(item);
 429		if (parser->global.report_id == 0 ||
 430		    parser->global.report_id >= HID_MAX_IDS) {
 431			hid_err(parser->device, "report_id %u is invalid\n",
 432				parser->global.report_id);
 433			return -1;
 434		}
 435		return 0;
 436
 437	default:
 438		hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
 439		return -1;
 440	}
 441}
 442
 443/*
 444 * Process a local item.
 445 */
 446
 447static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 448{
 449	__u32 data;
 450	unsigned n;
 451	__u32 count;
 452
 453	data = item_udata(item);
 454
 455	switch (item->tag) {
 456	case HID_LOCAL_ITEM_TAG_DELIMITER:
 457
 458		if (data) {
 459			/*
 460			 * We treat items before the first delimiter
 461			 * as global to all usage sets (branch 0).
 462			 * In the moment we process only these global
 463			 * items and the first delimiter set.
 464			 */
 465			if (parser->local.delimiter_depth != 0) {
 466				hid_err(parser->device, "nested delimiters\n");
 467				return -1;
 468			}
 469			parser->local.delimiter_depth++;
 470			parser->local.delimiter_branch++;
 471		} else {
 472			if (parser->local.delimiter_depth < 1) {
 473				hid_err(parser->device, "bogus close delimiter\n");
 474				return -1;
 475			}
 476			parser->local.delimiter_depth--;
 477		}
 478		return 0;
 479
 480	case HID_LOCAL_ITEM_TAG_USAGE:
 481
 482		if (parser->local.delimiter_branch > 1) {
 483			dbg_hid("alternative usage ignored\n");
 484			return 0;
 485		}
 486
 487		return hid_add_usage(parser, data, item->size);
 
 
 
 488
 489	case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
 490
 491		if (parser->local.delimiter_branch > 1) {
 492			dbg_hid("alternative usage ignored\n");
 493			return 0;
 494		}
 495
 
 
 
 496		parser->local.usage_minimum = data;
 497		return 0;
 498
 499	case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
 500
 501		if (parser->local.delimiter_branch > 1) {
 502			dbg_hid("alternative usage ignored\n");
 503			return 0;
 504		}
 505
 506		count = data - parser->local.usage_minimum;
 507		if (count + parser->local.usage_index >= HID_MAX_USAGES) {
 508			/*
 509			 * We do not warn if the name is not set, we are
 510			 * actually pre-scanning the device.
 511			 */
 512			if (dev_name(&parser->device->dev))
 513				hid_warn(parser->device,
 514					 "ignoring exceeding usage max\n");
 515			data = HID_MAX_USAGES - parser->local.usage_index +
 516				parser->local.usage_minimum - 1;
 517			if (data <= 0) {
 518				hid_err(parser->device,
 519					"no more usage index available\n");
 520				return -1;
 521			}
 522		}
 523
 524		for (n = parser->local.usage_minimum; n <= data; n++)
 525			if (hid_add_usage(parser, n, item->size)) {
 526				dbg_hid("hid_add_usage failed\n");
 527				return -1;
 528			}
 529		return 0;
 530
 531	default:
 532
 533		dbg_hid("unknown local item tag 0x%x\n", item->tag);
 534		return 0;
 535	}
 536	return 0;
 537}
 538
 539/*
 540 * Concatenate Usage Pages into Usages where relevant:
 541 * As per specification, 6.2.2.8: "When the parser encounters a main item it
 542 * concatenates the last declared Usage Page with a Usage to form a complete
 543 * usage value."
 544 */
 545
 546static void hid_concatenate_usage_page(struct hid_parser *parser)
 547{
 548	int i;
 549
 550	for (i = 0; i < parser->local.usage_index; i++)
 551		if (parser->local.usage_size[i] <= 2)
 552			parser->local.usage[i] += parser->global.usage_page << 16;
 553}
 554
 555/*
 556 * Process a main item.
 557 */
 558
 559static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
 560{
 561	__u32 data;
 562	int ret;
 563
 564	hid_concatenate_usage_page(parser);
 565
 566	data = item_udata(item);
 567
 568	switch (item->tag) {
 569	case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 570		ret = open_collection(parser, data & 0xff);
 571		break;
 572	case HID_MAIN_ITEM_TAG_END_COLLECTION:
 573		ret = close_collection(parser);
 574		break;
 575	case HID_MAIN_ITEM_TAG_INPUT:
 576		ret = hid_add_field(parser, HID_INPUT_REPORT, data);
 577		break;
 578	case HID_MAIN_ITEM_TAG_OUTPUT:
 579		ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
 580		break;
 581	case HID_MAIN_ITEM_TAG_FEATURE:
 582		ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
 583		break;
 584	default:
 585		hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag);
 586		ret = 0;
 587	}
 588
 589	memset(&parser->local, 0, sizeof(parser->local));	/* Reset the local parser environment */
 590
 591	return ret;
 592}
 593
 594/*
 595 * Process a reserved item.
 596 */
 597
 598static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
 599{
 600	dbg_hid("reserved item type, tag 0x%x\n", item->tag);
 601	return 0;
 602}
 603
 604/*
 605 * Free a report and all registered fields. The field->usage and
 606 * field->value table's are allocated behind the field, so we need
 607 * only to free(field) itself.
 608 */
 609
 610static void hid_free_report(struct hid_report *report)
 611{
 612	unsigned n;
 613
 614	for (n = 0; n < report->maxfield; n++)
 615		kfree(report->field[n]);
 616	kfree(report);
 617}
 618
 619/*
 620 * Close report. This function returns the device
 621 * state to the point prior to hid_open_report().
 622 */
 623static void hid_close_report(struct hid_device *device)
 
 624{
 
 625	unsigned i, j;
 626
 627	for (i = 0; i < HID_REPORT_TYPES; i++) {
 628		struct hid_report_enum *report_enum = device->report_enum + i;
 629
 630		for (j = 0; j < HID_MAX_IDS; j++) {
 631			struct hid_report *report = report_enum->report_id_hash[j];
 632			if (report)
 633				hid_free_report(report);
 634		}
 635		memset(report_enum, 0, sizeof(*report_enum));
 636		INIT_LIST_HEAD(&report_enum->report_list);
 637	}
 638
 639	kfree(device->rdesc);
 640	device->rdesc = NULL;
 641	device->rsize = 0;
 642
 643	kfree(device->collection);
 644	device->collection = NULL;
 645	device->collection_size = 0;
 646	device->maxcollection = 0;
 647	device->maxapplication = 0;
 648
 649	device->status &= ~HID_STAT_PARSED;
 650}
 651
 652/*
 653 * Free a device structure, all reports, and all fields.
 654 */
 655
 656static void hid_device_release(struct device *dev)
 657{
 658	struct hid_device *hid = to_hid_device(dev);
 659
 660	hid_close_report(hid);
 661	kfree(hid->dev_rdesc);
 662	kfree(hid);
 663}
 664
 665/*
 666 * Fetch a report description item from the data stream. We support long
 667 * items, though they are not used yet.
 668 */
 669
 670static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
 671{
 672	u8 b;
 673
 674	if ((end - start) <= 0)
 675		return NULL;
 676
 677	b = *start++;
 678
 679	item->type = (b >> 2) & 3;
 680	item->tag  = (b >> 4) & 15;
 681
 682	if (item->tag == HID_ITEM_TAG_LONG) {
 683
 684		item->format = HID_ITEM_FORMAT_LONG;
 685
 686		if ((end - start) < 2)
 687			return NULL;
 688
 689		item->size = *start++;
 690		item->tag  = *start++;
 691
 692		if ((end - start) < item->size)
 693			return NULL;
 694
 695		item->data.longdata = start;
 696		start += item->size;
 697		return start;
 698	}
 699
 700	item->format = HID_ITEM_FORMAT_SHORT;
 701	item->size = b & 3;
 702
 703	switch (item->size) {
 704	case 0:
 705		return start;
 706
 707	case 1:
 708		if ((end - start) < 1)
 709			return NULL;
 710		item->data.u8 = *start++;
 711		return start;
 712
 713	case 2:
 714		if ((end - start) < 2)
 715			return NULL;
 716		item->data.u16 = get_unaligned_le16(start);
 717		start = (__u8 *)((__le16 *)start + 1);
 718		return start;
 719
 720	case 3:
 721		item->size++;
 722		if ((end - start) < 4)
 723			return NULL;
 724		item->data.u32 = get_unaligned_le32(start);
 725		start = (__u8 *)((__le32 *)start + 1);
 726		return start;
 727	}
 728
 729	return NULL;
 730}
 731
 732static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
 733{
 734	struct hid_device *hid = parser->device;
 735
 736	if (usage == HID_DG_CONTACTID)
 737		hid->group = HID_GROUP_MULTITOUCH;
 738}
 739
 740static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
 741{
 742	if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
 743	    parser->global.report_size == 8)
 744		parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 745}
 746
 747static void hid_scan_collection(struct hid_parser *parser, unsigned type)
 748{
 749	struct hid_device *hid = parser->device;
 750	int i;
 751
 752	if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
 753	    type == HID_COLLECTION_PHYSICAL)
 754		hid->group = HID_GROUP_SENSOR_HUB;
 755
 756	if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
 757	    hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
 758	    hid->group == HID_GROUP_MULTITOUCH)
 759		hid->group = HID_GROUP_GENERIC;
 760
 761	if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
 762		for (i = 0; i < parser->local.usage_index; i++)
 763			if (parser->local.usage[i] == HID_GD_POINTER)
 764				parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
 765
 766	if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
 767		parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
 768}
 769
 770static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
 771{
 772	__u32 data;
 773	int i;
 774
 775	hid_concatenate_usage_page(parser);
 776
 777	data = item_udata(item);
 778
 779	switch (item->tag) {
 780	case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 781		hid_scan_collection(parser, data & 0xff);
 782		break;
 783	case HID_MAIN_ITEM_TAG_END_COLLECTION:
 784		break;
 785	case HID_MAIN_ITEM_TAG_INPUT:
 786		/* ignore constant inputs, they will be ignored by hid-input */
 787		if (data & HID_MAIN_ITEM_CONSTANT)
 788			break;
 789		for (i = 0; i < parser->local.usage_index; i++)
 790			hid_scan_input_usage(parser, parser->local.usage[i]);
 791		break;
 792	case HID_MAIN_ITEM_TAG_OUTPUT:
 793		break;
 794	case HID_MAIN_ITEM_TAG_FEATURE:
 795		for (i = 0; i < parser->local.usage_index; i++)
 796			hid_scan_feature_usage(parser, parser->local.usage[i]);
 797		break;
 798	}
 799
 800	/* Reset the local parser environment */
 801	memset(&parser->local, 0, sizeof(parser->local));
 802
 803	return 0;
 804}
 805
 806/*
 807 * Scan a report descriptor before the device is added to the bus.
 808 * Sets device groups and other properties that determine what driver
 809 * to load.
 810 */
 811static int hid_scan_report(struct hid_device *hid)
 812{
 813	struct hid_parser *parser;
 814	struct hid_item item;
 815	__u8 *start = hid->dev_rdesc;
 816	__u8 *end = start + hid->dev_rsize;
 817	static int (*dispatch_type[])(struct hid_parser *parser,
 818				      struct hid_item *item) = {
 819		hid_scan_main,
 820		hid_parser_global,
 821		hid_parser_local,
 822		hid_parser_reserved
 823	};
 824
 825	parser = vzalloc(sizeof(struct hid_parser));
 826	if (!parser)
 827		return -ENOMEM;
 828
 829	parser->device = hid;
 830	hid->group = HID_GROUP_GENERIC;
 831
 832	/*
 833	 * The parsing is simpler than the one in hid_open_report() as we should
 834	 * be robust against hid errors. Those errors will be raised by
 835	 * hid_open_report() anyway.
 836	 */
 837	while ((start = fetch_item(start, end, &item)) != NULL)
 838		dispatch_type[item.type](parser, &item);
 839
 840	/*
 841	 * Handle special flags set during scanning.
 842	 */
 843	if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
 844	    (hid->group == HID_GROUP_MULTITOUCH))
 845		hid->group = HID_GROUP_MULTITOUCH_WIN_8;
 846
 847	/*
 848	 * Vendor specific handlings
 849	 */
 850	switch (hid->vendor) {
 851	case USB_VENDOR_ID_WACOM:
 852		hid->group = HID_GROUP_WACOM;
 853		break;
 854	case USB_VENDOR_ID_SYNAPTICS:
 855		if (hid->group == HID_GROUP_GENERIC)
 856			if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
 857			    && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
 858				/*
 859				 * hid-rmi should take care of them,
 860				 * not hid-generic
 861				 */
 862				hid->group = HID_GROUP_RMI;
 863		break;
 864	}
 865
 866	kfree(parser->collection_stack);
 867	vfree(parser);
 868	return 0;
 869}
 870
 871/**
 872 * hid_parse_report - parse device report
 873 *
 874 * @device: hid device
 875 * @start: report start
 876 * @size: report size
 877 *
 878 * Allocate the device report as read by the bus driver. This function should
 879 * only be called from parse() in ll drivers.
 880 */
 881int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
 882{
 883	hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
 884	if (!hid->dev_rdesc)
 885		return -ENOMEM;
 886	hid->dev_rsize = size;
 887	return 0;
 888}
 889EXPORT_SYMBOL_GPL(hid_parse_report);
 890
 891static const char * const hid_report_names[] = {
 892	"HID_INPUT_REPORT",
 893	"HID_OUTPUT_REPORT",
 894	"HID_FEATURE_REPORT",
 895};
 896/**
 897 * hid_validate_values - validate existing device report's value indexes
 898 *
 899 * @device: hid device
 900 * @type: which report type to examine
 901 * @id: which report ID to examine (0 for first)
 902 * @field_index: which report field to examine
 903 * @report_counts: expected number of values
 904 *
 905 * Validate the number of values in a given field of a given report, after
 906 * parsing.
 907 */
 908struct hid_report *hid_validate_values(struct hid_device *hid,
 909				       unsigned int type, unsigned int id,
 910				       unsigned int field_index,
 911				       unsigned int report_counts)
 912{
 913	struct hid_report *report;
 914
 915	if (type > HID_FEATURE_REPORT) {
 916		hid_err(hid, "invalid HID report type %u\n", type);
 917		return NULL;
 918	}
 919
 920	if (id >= HID_MAX_IDS) {
 921		hid_err(hid, "invalid HID report id %u\n", id);
 922		return NULL;
 923	}
 924
 925	/*
 926	 * Explicitly not using hid_get_report() here since it depends on
 927	 * ->numbered being checked, which may not always be the case when
 928	 * drivers go to access report values.
 929	 */
 930	if (id == 0) {
 931		/*
 932		 * Validating on id 0 means we should examine the first
 933		 * report in the list.
 934		 */
 935		report = list_entry(
 936				hid->report_enum[type].report_list.next,
 937				struct hid_report, list);
 938	} else {
 939		report = hid->report_enum[type].report_id_hash[id];
 940	}
 941	if (!report) {
 942		hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
 943		return NULL;
 944	}
 945	if (report->maxfield <= field_index) {
 946		hid_err(hid, "not enough fields in %s %u\n",
 947			hid_report_names[type], id);
 948		return NULL;
 949	}
 950	if (report->field[field_index]->report_count < report_counts) {
 951		hid_err(hid, "not enough values in %s %u field %u\n",
 952			hid_report_names[type], id, field_index);
 953		return NULL;
 954	}
 955	return report;
 956}
 957EXPORT_SYMBOL_GPL(hid_validate_values);
 958
 959static int hid_calculate_multiplier(struct hid_device *hid,
 960				     struct hid_field *multiplier)
 961{
 962	int m;
 963	__s32 v = *multiplier->value;
 964	__s32 lmin = multiplier->logical_minimum;
 965	__s32 lmax = multiplier->logical_maximum;
 966	__s32 pmin = multiplier->physical_minimum;
 967	__s32 pmax = multiplier->physical_maximum;
 968
 969	/*
 970	 * "Because OS implementations will generally divide the control's
 971	 * reported count by the Effective Resolution Multiplier, designers
 972	 * should take care not to establish a potential Effective
 973	 * Resolution Multiplier of zero."
 974	 * HID Usage Table, v1.12, Section 4.3.1, p31
 975	 */
 976	if (lmax - lmin == 0)
 977		return 1;
 978	/*
 979	 * Handling the unit exponent is left as an exercise to whoever
 980	 * finds a device where that exponent is not 0.
 981	 */
 982	m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
 983	if (unlikely(multiplier->unit_exponent != 0)) {
 984		hid_warn(hid,
 985			 "unsupported Resolution Multiplier unit exponent %d\n",
 986			 multiplier->unit_exponent);
 987	}
 988
 989	/* There are no devices with an effective multiplier > 255 */
 990	if (unlikely(m == 0 || m > 255 || m < -255)) {
 991		hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
 992		m = 1;
 993	}
 994
 995	return m;
 996}
 997
 998static void hid_apply_multiplier_to_field(struct hid_device *hid,
 999					  struct hid_field *field,
1000					  struct hid_collection *multiplier_collection,
1001					  int effective_multiplier)
1002{
1003	struct hid_collection *collection;
1004	struct hid_usage *usage;
1005	int i;
1006
1007	/*
1008	 * If multiplier_collection is NULL, the multiplier applies
1009	 * to all fields in the report.
1010	 * Otherwise, it is the Logical Collection the multiplier applies to
1011	 * but our field may be in a subcollection of that collection.
1012	 */
1013	for (i = 0; i < field->maxusage; i++) {
1014		usage = &field->usage[i];
1015
1016		collection = &hid->collection[usage->collection_index];
1017		while (collection->parent_idx != -1 &&
1018		       collection != multiplier_collection)
1019			collection = &hid->collection[collection->parent_idx];
1020
1021		if (collection->parent_idx != -1 ||
1022		    multiplier_collection == NULL)
1023			usage->resolution_multiplier = effective_multiplier;
1024
1025	}
1026}
1027
1028static void hid_apply_multiplier(struct hid_device *hid,
1029				 struct hid_field *multiplier)
1030{
1031	struct hid_report_enum *rep_enum;
1032	struct hid_report *rep;
1033	struct hid_field *field;
1034	struct hid_collection *multiplier_collection;
1035	int effective_multiplier;
1036	int i;
1037
1038	/*
1039	 * "The Resolution Multiplier control must be contained in the same
1040	 * Logical Collection as the control(s) to which it is to be applied.
1041	 * If no Resolution Multiplier is defined, then the Resolution
1042	 * Multiplier defaults to 1.  If more than one control exists in a
1043	 * Logical Collection, the Resolution Multiplier is associated with
1044	 * all controls in the collection. If no Logical Collection is
1045	 * defined, the Resolution Multiplier is associated with all
1046	 * controls in the report."
1047	 * HID Usage Table, v1.12, Section 4.3.1, p30
1048	 *
1049	 * Thus, search from the current collection upwards until we find a
1050	 * logical collection. Then search all fields for that same parent
1051	 * collection. Those are the fields the multiplier applies to.
1052	 *
1053	 * If we have more than one multiplier, it will overwrite the
1054	 * applicable fields later.
1055	 */
1056	multiplier_collection = &hid->collection[multiplier->usage->collection_index];
1057	while (multiplier_collection->parent_idx != -1 &&
1058	       multiplier_collection->type != HID_COLLECTION_LOGICAL)
1059		multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
1060
1061	effective_multiplier = hid_calculate_multiplier(hid, multiplier);
1062
1063	rep_enum = &hid->report_enum[HID_INPUT_REPORT];
1064	list_for_each_entry(rep, &rep_enum->report_list, list) {
1065		for (i = 0; i < rep->maxfield; i++) {
1066			field = rep->field[i];
1067			hid_apply_multiplier_to_field(hid, field,
1068						      multiplier_collection,
1069						      effective_multiplier);
1070		}
1071	}
1072}
1073
1074/*
1075 * hid_setup_resolution_multiplier - set up all resolution multipliers
1076 *
1077 * @device: hid device
1078 *
1079 * Search for all Resolution Multiplier Feature Reports and apply their
1080 * value to all matching Input items. This only updates the internal struct
1081 * fields.
1082 *
1083 * The Resolution Multiplier is applied by the hardware. If the multiplier
1084 * is anything other than 1, the hardware will send pre-multiplied events
1085 * so that the same physical interaction generates an accumulated
1086 *	accumulated_value = value * * multiplier
1087 * This may be achieved by sending
1088 * - "value * multiplier" for each event, or
1089 * - "value" but "multiplier" times as frequently, or
1090 * - a combination of the above
1091 * The only guarantee is that the same physical interaction always generates
1092 * an accumulated 'value * multiplier'.
1093 *
1094 * This function must be called before any event processing and after
1095 * any SetRequest to the Resolution Multiplier.
1096 */
1097void hid_setup_resolution_multiplier(struct hid_device *hid)
1098{
1099	struct hid_report_enum *rep_enum;
1100	struct hid_report *rep;
1101	struct hid_usage *usage;
1102	int i, j;
1103
1104	rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
1105	list_for_each_entry(rep, &rep_enum->report_list, list) {
1106		for (i = 0; i < rep->maxfield; i++) {
1107			/* Ignore if report count is out of bounds. */
1108			if (rep->field[i]->report_count < 1)
1109				continue;
1110
1111			for (j = 0; j < rep->field[i]->maxusage; j++) {
1112				usage = &rep->field[i]->usage[j];
1113				if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
1114					hid_apply_multiplier(hid,
1115							     rep->field[i]);
1116			}
1117		}
1118	}
1119}
1120EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
1121
1122/**
1123 * hid_open_report - open a driver-specific device report
1124 *
1125 * @device: hid device
1126 *
1127 * Parse a report description into a hid_device structure. Reports are
1128 * enumerated, fields are attached to these reports.
1129 * 0 returned on success, otherwise nonzero error value.
1130 *
1131 * This function (or the equivalent hid_parse() macro) should only be
1132 * called from probe() in drivers, before starting the device.
1133 */
1134int hid_open_report(struct hid_device *device)
 
1135{
1136	struct hid_parser *parser;
1137	struct hid_item item;
1138	unsigned int size;
1139	__u8 *start;
1140	__u8 *buf;
1141	__u8 *end;
1142	__u8 *next;
1143	int ret;
1144	static int (*dispatch_type[])(struct hid_parser *parser,
1145				      struct hid_item *item) = {
1146		hid_parser_main,
1147		hid_parser_global,
1148		hid_parser_local,
1149		hid_parser_reserved
1150	};
1151
1152	if (WARN_ON(device->status & HID_STAT_PARSED))
1153		return -EBUSY;
1154
1155	start = device->dev_rdesc;
1156	if (WARN_ON(!start))
1157		return -ENODEV;
1158	size = device->dev_rsize;
1159
1160	buf = kmemdup(start, size, GFP_KERNEL);
1161	if (buf == NULL)
1162		return -ENOMEM;
1163
1164	if (device->driver->report_fixup)
1165		start = device->driver->report_fixup(device, buf, &size);
1166	else
1167		start = buf;
1168
1169	start = kmemdup(start, size, GFP_KERNEL);
1170	kfree(buf);
1171	if (start == NULL)
1172		return -ENOMEM;
1173
1174	device->rdesc = start;
1175	device->rsize = size;
1176
1177	parser = vzalloc(sizeof(struct hid_parser));
1178	if (!parser) {
1179		ret = -ENOMEM;
1180		goto alloc_err;
1181	}
1182
1183	parser->device = device;
1184
1185	end = start + size;
1186
1187	device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
1188				     sizeof(struct hid_collection), GFP_KERNEL);
1189	if (!device->collection) {
1190		ret = -ENOMEM;
1191		goto err;
1192	}
1193	device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
1194
1195	ret = -EINVAL;
1196	while ((next = fetch_item(start, end, &item)) != NULL) {
1197		start = next;
1198
1199		if (item.format != HID_ITEM_FORMAT_SHORT) {
1200			hid_err(device, "unexpected long global item\n");
1201			goto err;
1202		}
1203
1204		if (dispatch_type[item.type](parser, &item)) {
1205			hid_err(device, "item %u %u %u %u parsing failed\n",
1206				item.format, (unsigned)item.size,
1207				(unsigned)item.type, (unsigned)item.tag);
1208			goto err;
1209		}
1210
1211		if (start == end) {
1212			if (parser->collection_stack_ptr) {
1213				hid_err(device, "unbalanced collection at end of report description\n");
1214				goto err;
1215			}
1216			if (parser->local.delimiter_depth) {
1217				hid_err(device, "unbalanced delimiter at end of report description\n");
1218				goto err;
1219			}
1220
1221			/*
1222			 * fetch initial values in case the device's
1223			 * default multiplier isn't the recommended 1
1224			 */
1225			hid_setup_resolution_multiplier(device);
1226
1227			kfree(parser->collection_stack);
1228			vfree(parser);
1229			device->status |= HID_STAT_PARSED;
1230
1231			return 0;
1232		}
1233	}
1234
1235	hid_err(device, "item fetching failed at offset %u/%u\n",
1236		size - (unsigned int)(end - start), size);
1237err:
1238	kfree(parser->collection_stack);
1239alloc_err:
1240	vfree(parser);
1241	hid_close_report(device);
1242	return ret;
1243}
1244EXPORT_SYMBOL_GPL(hid_open_report);
1245
1246/*
1247 * Convert a signed n-bit integer to signed 32-bit integer. Common
1248 * cases are done through the compiler, the screwed things has to be
1249 * done by hand.
1250 */
1251
1252static s32 snto32(__u32 value, unsigned n)
1253{
1254	switch (n) {
1255	case 8:  return ((__s8)value);
1256	case 16: return ((__s16)value);
1257	case 32: return ((__s32)value);
1258	}
1259	return value & (1 << (n - 1)) ? value | (~0U << n) : value;
1260}
1261
1262s32 hid_snto32(__u32 value, unsigned n)
1263{
1264	return snto32(value, n);
1265}
1266EXPORT_SYMBOL_GPL(hid_snto32);
1267
1268/*
1269 * Convert a signed 32-bit integer to a signed n-bit integer.
1270 */
1271
1272static u32 s32ton(__s32 value, unsigned n)
1273{
1274	s32 a = value >> (n - 1);
1275	if (a && a != -1)
1276		return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
1277	return value & ((1 << n) - 1);
1278}
1279
1280/*
1281 * Extract/implement a data field from/to a little endian report (bit array).
1282 *
1283 * Code sort-of follows HID spec:
1284 *     http://www.usb.org/developers/hidpage/HID1_11.pdf
1285 *
1286 * While the USB HID spec allows unlimited length bit fields in "report
1287 * descriptors", most devices never use more than 16 bits.
1288 * One model of UPS is claimed to report "LINEV" as a 32-bit field.
1289 * Search linux-kernel and linux-usb-devel archives for "hid-core extract".
1290 */
1291
1292static u32 __extract(u8 *report, unsigned offset, int n)
 
1293{
1294	unsigned int idx = offset / 8;
1295	unsigned int bit_nr = 0;
1296	unsigned int bit_shift = offset % 8;
1297	int bits_to_copy = 8 - bit_shift;
1298	u32 value = 0;
1299	u32 mask = n < 32 ? (1U << n) - 1 : ~0U;
1300
1301	while (n > 0) {
1302		value |= ((u32)report[idx] >> bit_shift) << bit_nr;
1303		n -= bits_to_copy;
1304		bit_nr += bits_to_copy;
1305		bits_to_copy = 8;
1306		bit_shift = 0;
1307		idx++;
1308	}
1309
1310	return value & mask;
 
 
 
 
 
 
 
 
1311}
1312
1313u32 hid_field_extract(const struct hid_device *hid, u8 *report,
1314			unsigned offset, unsigned n)
1315{
1316	if (n > 32) {
1317		hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
1318			      __func__, n, current->comm);
1319		n = 32;
1320	}
1321
1322	return __extract(report, offset, n);
1323}
1324EXPORT_SYMBOL_GPL(hid_field_extract);
1325
1326/*
1327 * "implement" : set bits in a little endian bit stream.
1328 * Same concepts as "extract" (see comments above).
1329 * The data mangled in the bit stream remains in little endian
1330 * order the whole time. It make more sense to talk about
1331 * endianness of register values by considering a register
1332 * a "cached" copy of the little endian bit stream.
1333 */
1334
1335static void __implement(u8 *report, unsigned offset, int n, u32 value)
1336{
1337	unsigned int idx = offset / 8;
1338	unsigned int bit_shift = offset % 8;
1339	int bits_to_set = 8 - bit_shift;
1340
1341	while (n - bits_to_set >= 0) {
1342		report[idx] &= ~(0xff << bit_shift);
1343		report[idx] |= value << bit_shift;
1344		value >>= bits_to_set;
1345		n -= bits_to_set;
1346		bits_to_set = 8;
1347		bit_shift = 0;
1348		idx++;
1349	}
1350
1351	/* last nibble */
1352	if (n) {
1353		u8 bit_mask = ((1U << n) - 1);
1354		report[idx] &= ~(bit_mask << bit_shift);
1355		report[idx] |= value << bit_shift;
1356	}
1357}
1358
1359static void implement(const struct hid_device *hid, u8 *report,
1360		      unsigned offset, unsigned n, u32 value)
1361{
1362	if (unlikely(n > 32)) {
1363		hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
1364			 __func__, n, current->comm);
1365		n = 32;
1366	} else if (n < 32) {
1367		u32 m = (1U << n) - 1;
1368
1369		if (unlikely(value > m)) {
1370			hid_warn(hid,
1371				 "%s() called with too large value %d (n: %d)! (%s)\n",
1372				 __func__, value, n, current->comm);
1373			WARN_ON(1);
1374			value &= m;
1375		}
1376	}
1377
1378	__implement(report, offset, n, value);
 
 
 
 
 
 
 
 
 
 
 
 
1379}
1380
1381/*
1382 * Search an array for a value.
1383 */
1384
1385static int search(__s32 *array, __s32 value, unsigned n)
1386{
1387	while (n--) {
1388		if (*array++ == value)
1389			return 0;
1390	}
1391	return -1;
1392}
1393
1394/**
1395 * hid_match_report - check if driver's raw_event should be called
1396 *
1397 * @hid: hid device
1398 * @report_type: type to match against
1399 *
1400 * compare hid->driver->report_table->report_type to report->type
1401 */
1402static int hid_match_report(struct hid_device *hid, struct hid_report *report)
1403{
1404	const struct hid_report_id *id = hid->driver->report_table;
1405
1406	if (!id) /* NULL means all */
1407		return 1;
1408
1409	for (; id->report_type != HID_TERMINATOR; id++)
1410		if (id->report_type == HID_ANY_ID ||
1411				id->report_type == report->type)
1412			return 1;
1413	return 0;
1414}
1415
1416/**
1417 * hid_match_usage - check if driver's event should be called
1418 *
1419 * @hid: hid device
1420 * @usage: usage to match against
1421 *
1422 * compare hid->driver->usage_table->usage_{type,code} to
1423 * usage->usage_{type,code}
1424 */
1425static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage)
1426{
1427	const struct hid_usage_id *id = hid->driver->usage_table;
1428
1429	if (!id) /* NULL means all */
1430		return 1;
1431
1432	for (; id->usage_type != HID_ANY_ID - 1; id++)
1433		if ((id->usage_hid == HID_ANY_ID ||
1434				id->usage_hid == usage->hid) &&
1435				(id->usage_type == HID_ANY_ID ||
1436				id->usage_type == usage->type) &&
1437				(id->usage_code == HID_ANY_ID ||
1438				 id->usage_code == usage->code))
1439			return 1;
1440	return 0;
1441}
1442
1443static void hid_process_event(struct hid_device *hid, struct hid_field *field,
1444		struct hid_usage *usage, __s32 value, int interrupt)
1445{
1446	struct hid_driver *hdrv = hid->driver;
1447	int ret;
1448
1449	if (!list_empty(&hid->debug_list))
1450		hid_dump_input(hid, usage, value);
1451
1452	if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
1453		ret = hdrv->event(hid, field, usage, value);
1454		if (ret != 0) {
1455			if (ret < 0)
1456				hid_err(hid, "%s's event failed with %d\n",
1457						hdrv->name, ret);
1458			return;
1459		}
1460	}
1461
1462	if (hid->claimed & HID_CLAIMED_INPUT)
1463		hidinput_hid_event(hid, field, usage, value);
1464	if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
1465		hid->hiddev_hid_event(hid, field, usage, value);
1466}
1467
1468/*
1469 * Analyse a received field, and fetch the data from it. The field
1470 * content is stored for next report processing (we do differential
1471 * reporting to the layer).
1472 */
1473
1474static void hid_input_field(struct hid_device *hid, struct hid_field *field,
1475			    __u8 *data, int interrupt)
1476{
1477	unsigned n;
1478	unsigned count = field->report_count;
1479	unsigned offset = field->report_offset;
1480	unsigned size = field->report_size;
1481	__s32 min = field->logical_minimum;
1482	__s32 max = field->logical_maximum;
1483	__s32 *value;
1484
1485	value = kmalloc_array(count, sizeof(__s32), GFP_ATOMIC);
1486	if (!value)
1487		return;
1488
1489	for (n = 0; n < count; n++) {
1490
1491		value[n] = min < 0 ?
1492			snto32(hid_field_extract(hid, data, offset + n * size,
1493			       size), size) :
1494			hid_field_extract(hid, data, offset + n * size, size);
1495
1496		/* Ignore report if ErrorRollOver */
1497		if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&
1498		    value[n] >= min && value[n] <= max &&
1499		    value[n] - min < field->maxusage &&
1500		    field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1)
1501			goto exit;
1502	}
1503
1504	for (n = 0; n < count; n++) {
1505
1506		if (HID_MAIN_ITEM_VARIABLE & field->flags) {
1507			hid_process_event(hid, field, &field->usage[n], value[n], interrupt);
1508			continue;
1509		}
1510
1511		if (field->value[n] >= min && field->value[n] <= max
1512			&& field->value[n] - min < field->maxusage
1513			&& field->usage[field->value[n] - min].hid
1514			&& search(value, field->value[n], count))
1515				hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt);
1516
1517		if (value[n] >= min && value[n] <= max
1518			&& value[n] - min < field->maxusage
1519			&& field->usage[value[n] - min].hid
1520			&& search(field->value, value[n], count))
1521				hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt);
1522	}
1523
1524	memcpy(field->value, value, count * sizeof(__s32));
1525exit:
1526	kfree(value);
1527}
1528
1529/*
1530 * Output the field into the report.
1531 */
1532
1533static void hid_output_field(const struct hid_device *hid,
1534			     struct hid_field *field, __u8 *data)
1535{
1536	unsigned count = field->report_count;
1537	unsigned offset = field->report_offset;
1538	unsigned size = field->report_size;
1539	unsigned n;
1540
1541	for (n = 0; n < count; n++) {
1542		if (field->logical_minimum < 0)	/* signed values */
1543			implement(hid, data, offset + n * size, size,
1544				  s32ton(field->value[n], size));
1545		else				/* unsigned values */
1546			implement(hid, data, offset + n * size, size,
1547				  field->value[n]);
1548	}
1549}
1550
1551/*
1552 * Create a report. 'data' has to be allocated using
1553 * hid_alloc_report_buf() so that it has proper size.
1554 */
1555
1556void hid_output_report(struct hid_report *report, __u8 *data)
1557{
1558	unsigned n;
1559
1560	if (report->id > 0)
1561		*data++ = report->id;
1562
1563	memset(data, 0, ((report->size - 1) >> 3) + 1);
1564	for (n = 0; n < report->maxfield; n++)
1565		hid_output_field(report->device, report->field[n], data);
1566}
1567EXPORT_SYMBOL_GPL(hid_output_report);
1568
1569/*
1570 * Allocator for buffer that is going to be passed to hid_output_report()
1571 */
1572u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
1573{
1574	/*
1575	 * 7 extra bytes are necessary to achieve proper functionality
1576	 * of implement() working on 8 byte chunks
1577	 */
1578
1579	u32 len = hid_report_len(report) + 7;
1580
1581	return kmalloc(len, flags);
1582}
1583EXPORT_SYMBOL_GPL(hid_alloc_report_buf);
1584
1585/*
1586 * Set a field value. The report this field belongs to has to be
1587 * created and transferred to the device, to set this value in the
1588 * device.
1589 */
1590
1591int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
1592{
1593	unsigned size;
1594
1595	if (!field)
1596		return -1;
1597
1598	size = field->report_size;
1599
1600	hid_dump_input(field->report->device, field->usage + offset, value);
1601
1602	if (offset >= field->report_count) {
1603		hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n",
1604				offset, field->report_count);
1605		return -1;
1606	}
1607	if (field->logical_minimum < 0) {
1608		if (value != snto32(s32ton(value, size), size)) {
1609			hid_err(field->report->device, "value %d is out of range\n", value);
1610			return -1;
1611		}
1612	}
1613	field->value[offset] = value;
1614	return 0;
1615}
1616EXPORT_SYMBOL_GPL(hid_set_field);
1617
1618static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
1619		const u8 *data)
1620{
1621	struct hid_report *report;
1622	unsigned int n = 0;	/* Normally report number is 0 */
1623
1624	/* Device uses numbered reports, data[0] is report number */
1625	if (report_enum->numbered)
1626		n = *data;
1627
1628	report = report_enum->report_id_hash[n];
1629	if (report == NULL)
1630		dbg_hid("undefined report_id %u received\n", n);
1631
1632	return report;
1633}
1634
1635/*
1636 * Implement a generic .request() callback, using .raw_request()
1637 * DO NOT USE in hid drivers directly, but through hid_hw_request instead.
1638 */
1639int __hid_request(struct hid_device *hid, struct hid_report *report,
1640		int reqtype)
1641{
1642	char *buf;
1643	int ret;
1644	u32 len;
1645
1646	buf = hid_alloc_report_buf(report, GFP_KERNEL);
1647	if (!buf)
1648		return -ENOMEM;
1649
1650	len = hid_report_len(report);
1651
1652	if (reqtype == HID_REQ_SET_REPORT)
1653		hid_output_report(report, buf);
1654
1655	ret = hid->ll_driver->raw_request(hid, report->id, buf, len,
1656					  report->type, reqtype);
1657	if (ret < 0) {
1658		dbg_hid("unable to complete request: %d\n", ret);
1659		goto out;
1660	}
1661
1662	if (reqtype == HID_REQ_GET_REPORT)
1663		hid_input_report(hid, report->type, buf, ret, 0);
1664
1665	ret = 0;
1666
1667out:
1668	kfree(buf);
1669	return ret;
1670}
1671EXPORT_SYMBOL_GPL(__hid_request);
1672
1673int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,
1674		int interrupt)
1675{
1676	struct hid_report_enum *report_enum = hid->report_enum + type;
1677	struct hid_report *report;
1678	struct hid_driver *hdrv;
1679	unsigned int a;
1680	u32 rsize, csize = size;
1681	u8 *cdata = data;
1682	int ret = 0;
1683
1684	report = hid_get_report(report_enum, data);
1685	if (!report)
1686		goto out;
1687
1688	if (report_enum->numbered) {
1689		cdata++;
1690		csize--;
1691	}
1692
1693	rsize = ((report->size - 1) >> 3) + 1;
1694
1695	if (rsize > HID_MAX_BUFFER_SIZE)
1696		rsize = HID_MAX_BUFFER_SIZE;
1697
1698	if (csize < rsize) {
1699		dbg_hid("report %d is too short, (%d < %d)\n", report->id,
1700				csize, rsize);
1701		memset(cdata + csize, 0, rsize - csize);
1702	}
1703
1704	if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
1705		hid->hiddev_report_event(hid, report);
1706	if (hid->claimed & HID_CLAIMED_HIDRAW) {
1707		ret = hidraw_report_event(hid, data, size);
1708		if (ret)
1709			goto out;
1710	}
1711
1712	if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
1713		for (a = 0; a < report->maxfield; a++)
1714			hid_input_field(hid, report->field[a], cdata, interrupt);
1715		hdrv = hid->driver;
1716		if (hdrv && hdrv->report)
1717			hdrv->report(hid, report);
1718	}
1719
1720	if (hid->claimed & HID_CLAIMED_INPUT)
1721		hidinput_report_event(hid, report);
1722out:
1723	return ret;
1724}
1725EXPORT_SYMBOL_GPL(hid_report_raw_event);
1726
1727/**
1728 * hid_input_report - report data from lower layer (usb, bt...)
1729 *
1730 * @hid: hid device
1731 * @type: HID report type (HID_*_REPORT)
1732 * @data: report contents
1733 * @size: size of data parameter
1734 * @interrupt: distinguish between interrupt and control transfers
1735 *
1736 * This is data entry for lower layers.
1737 */
1738int hid_input_report(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt)
1739{
1740	struct hid_report_enum *report_enum;
1741	struct hid_driver *hdrv;
1742	struct hid_report *report;
1743	int ret = 0;
 
 
1744
1745	if (!hid)
1746		return -ENODEV;
1747
1748	if (down_trylock(&hid->driver_input_lock))
1749		return -EBUSY;
1750
1751	if (!hid->driver) {
1752		ret = -ENODEV;
1753		goto unlock;
1754	}
1755	report_enum = hid->report_enum + type;
1756	hdrv = hid->driver;
1757
1758	if (!size) {
1759		dbg_hid("empty report\n");
1760		ret = -1;
1761		goto unlock;
1762	}
1763
1764	/* Avoid unnecessary overhead if debugfs is disabled */
1765	if (!list_empty(&hid->debug_list))
1766		hid_dump_report(hid, type, data, size);
1767
1768	report = hid_get_report(report_enum, data);
 
1769
1770	if (!report) {
1771		ret = -1;
1772		goto unlock;
 
 
 
 
 
 
1773	}
 
 
 
 
 
 
 
 
1774
1775	if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
1776		ret = hdrv->raw_event(hid, report, data, size);
1777		if (ret < 0)
1778			goto unlock;
1779	}
1780
1781	ret = hid_report_raw_event(hid, type, data, size, interrupt);
1782
1783unlock:
1784	up(&hid->driver_input_lock);
1785	return ret;
1786}
1787EXPORT_SYMBOL_GPL(hid_input_report);
1788
1789bool hid_match_one_id(const struct hid_device *hdev,
1790		      const struct hid_device_id *id)
1791{
1792	return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
1793		(id->group == HID_GROUP_ANY || id->group == hdev->group) &&
1794		(id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
1795		(id->product == HID_ANY_ID || id->product == hdev->product);
1796}
1797
1798const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
1799		const struct hid_device_id *id)
1800{
1801	for (; id->bus; id++)
1802		if (hid_match_one_id(hdev, id))
1803			return id;
1804
1805	return NULL;
1806}
1807
1808static const struct hid_device_id hid_hiddev_list[] = {
1809	{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
1810	{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
1811	{ }
1812};
1813
1814static bool hid_hiddev(struct hid_device *hdev)
1815{
1816	return !!hid_match_id(hdev, hid_hiddev_list);
1817}
1818
1819
1820static ssize_t
1821read_report_descriptor(struct file *filp, struct kobject *kobj,
1822		struct bin_attribute *attr,
1823		char *buf, loff_t off, size_t count)
1824{
1825	struct device *dev = kobj_to_dev(kobj);
1826	struct hid_device *hdev = to_hid_device(dev);
1827
1828	if (off >= hdev->rsize)
1829		return 0;
1830
1831	if (off + count > hdev->rsize)
1832		count = hdev->rsize - off;
1833
1834	memcpy(buf, hdev->rdesc + off, count);
1835
1836	return count;
1837}
1838
1839static ssize_t
1840show_country(struct device *dev, struct device_attribute *attr,
1841		char *buf)
1842{
1843	struct hid_device *hdev = to_hid_device(dev);
1844
1845	return sprintf(buf, "%02x\n", hdev->country & 0xff);
1846}
1847
1848static struct bin_attribute dev_bin_attr_report_desc = {
1849	.attr = { .name = "report_descriptor", .mode = 0444 },
1850	.read = read_report_descriptor,
1851	.size = HID_MAX_DESCRIPTOR_SIZE,
1852};
1853
1854static const struct device_attribute dev_attr_country = {
1855	.attr = { .name = "country", .mode = 0444 },
1856	.show = show_country,
1857};
1858
1859int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
1860{
1861	static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
1862		"Joystick", "Gamepad", "Keyboard", "Keypad",
1863		"Multi-Axis Controller"
1864	};
1865	const char *type, *bus;
1866	char buf[64] = "";
1867	unsigned int i;
1868	int len;
1869	int ret;
1870
1871	if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
1872		connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
1873	if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
1874		connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
1875	if (hdev->bus != BUS_USB)
1876		connect_mask &= ~HID_CONNECT_HIDDEV;
1877	if (hid_hiddev(hdev))
1878		connect_mask |= HID_CONNECT_HIDDEV_FORCE;
1879
1880	if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
1881				connect_mask & HID_CONNECT_HIDINPUT_FORCE))
1882		hdev->claimed |= HID_CLAIMED_INPUT;
1883
1884	if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
1885			!hdev->hiddev_connect(hdev,
1886				connect_mask & HID_CONNECT_HIDDEV_FORCE))
1887		hdev->claimed |= HID_CLAIMED_HIDDEV;
1888	if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
1889		hdev->claimed |= HID_CLAIMED_HIDRAW;
1890
1891	if (connect_mask & HID_CONNECT_DRIVER)
1892		hdev->claimed |= HID_CLAIMED_DRIVER;
1893
1894	/* Drivers with the ->raw_event callback set are not required to connect
1895	 * to any other listener. */
1896	if (!hdev->claimed && !hdev->driver->raw_event) {
1897		hid_err(hdev, "device has no listeners, quitting\n");
1898		return -ENODEV;
1899	}
1900
1901	if ((hdev->claimed & HID_CLAIMED_INPUT) &&
1902			(connect_mask & HID_CONNECT_FF) && hdev->ff_init)
1903		hdev->ff_init(hdev);
1904
1905	len = 0;
1906	if (hdev->claimed & HID_CLAIMED_INPUT)
1907		len += sprintf(buf + len, "input");
1908	if (hdev->claimed & HID_CLAIMED_HIDDEV)
1909		len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
1910				((struct hiddev *)hdev->hiddev)->minor);
1911	if (hdev->claimed & HID_CLAIMED_HIDRAW)
1912		len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
1913				((struct hidraw *)hdev->hidraw)->minor);
1914
1915	type = "Device";
1916	for (i = 0; i < hdev->maxcollection; i++) {
1917		struct hid_collection *col = &hdev->collection[i];
1918		if (col->type == HID_COLLECTION_APPLICATION &&
1919		   (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
1920		   (col->usage & 0xffff) < ARRAY_SIZE(types)) {
1921			type = types[col->usage & 0xffff];
1922			break;
1923		}
1924	}
1925
1926	switch (hdev->bus) {
1927	case BUS_USB:
1928		bus = "USB";
1929		break;
1930	case BUS_BLUETOOTH:
1931		bus = "BLUETOOTH";
1932		break;
1933	case BUS_I2C:
1934		bus = "I2C";
1935		break;
1936	default:
1937		bus = "<UNKNOWN>";
1938	}
1939
1940	ret = device_create_file(&hdev->dev, &dev_attr_country);
1941	if (ret)
1942		hid_warn(hdev,
1943			 "can't create sysfs country code attribute err: %d\n", ret);
1944
1945	hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
1946		 buf, bus, hdev->version >> 8, hdev->version & 0xff,
1947		 type, hdev->name, hdev->phys);
1948
1949	return 0;
1950}
1951EXPORT_SYMBOL_GPL(hid_connect);
1952
1953void hid_disconnect(struct hid_device *hdev)
1954{
1955	device_remove_file(&hdev->dev, &dev_attr_country);
1956	if (hdev->claimed & HID_CLAIMED_INPUT)
1957		hidinput_disconnect(hdev);
1958	if (hdev->claimed & HID_CLAIMED_HIDDEV)
1959		hdev->hiddev_disconnect(hdev);
1960	if (hdev->claimed & HID_CLAIMED_HIDRAW)
1961		hidraw_disconnect(hdev);
1962	hdev->claimed = 0;
1963}
1964EXPORT_SYMBOL_GPL(hid_disconnect);
1965
1966/**
1967 * hid_hw_start - start underlying HW
1968 * @hdev: hid device
1969 * @connect_mask: which outputs to connect, see HID_CONNECT_*
1970 *
1971 * Call this in probe function *after* hid_parse. This will setup HW
1972 * buffers and start the device (if not defeirred to device open).
1973 * hid_hw_stop must be called if this was successful.
1974 */
1975int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
1976{
1977	int error;
1978
1979	error = hdev->ll_driver->start(hdev);
1980	if (error)
1981		return error;
1982
1983	if (connect_mask) {
1984		error = hid_connect(hdev, connect_mask);
1985		if (error) {
1986			hdev->ll_driver->stop(hdev);
1987			return error;
1988		}
1989	}
1990
1991	return 0;
1992}
1993EXPORT_SYMBOL_GPL(hid_hw_start);
1994
1995/**
1996 * hid_hw_stop - stop underlying HW
1997 * @hdev: hid device
1998 *
1999 * This is usually called from remove function or from probe when something
2000 * failed and hid_hw_start was called already.
2001 */
2002void hid_hw_stop(struct hid_device *hdev)
2003{
2004	hid_disconnect(hdev);
2005	hdev->ll_driver->stop(hdev);
2006}
2007EXPORT_SYMBOL_GPL(hid_hw_stop);
2008
2009/**
2010 * hid_hw_open - signal underlying HW to start delivering events
2011 * @hdev: hid device
2012 *
2013 * Tell underlying HW to start delivering events from the device.
2014 * This function should be called sometime after successful call
2015 * to hid_hw_start().
2016 */
2017int hid_hw_open(struct hid_device *hdev)
2018{
2019	int ret;
2020
2021	ret = mutex_lock_killable(&hdev->ll_open_lock);
2022	if (ret)
2023		return ret;
2024
2025	if (!hdev->ll_open_count++) {
2026		ret = hdev->ll_driver->open(hdev);
2027		if (ret)
2028			hdev->ll_open_count--;
2029	}
2030
2031	mutex_unlock(&hdev->ll_open_lock);
2032	return ret;
2033}
2034EXPORT_SYMBOL_GPL(hid_hw_open);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2035
2036/**
2037 * hid_hw_close - signal underlaying HW to stop delivering events
2038 *
2039 * @hdev: hid device
2040 *
2041 * This function indicates that we are not interested in the events
2042 * from this device anymore. Delivery of events may or may not stop,
2043 * depending on the number of users still outstanding.
2044 */
2045void hid_hw_close(struct hid_device *hdev)
2046{
2047	mutex_lock(&hdev->ll_open_lock);
2048	if (!--hdev->ll_open_count)
2049		hdev->ll_driver->close(hdev);
2050	mutex_unlock(&hdev->ll_open_lock);
2051}
2052EXPORT_SYMBOL_GPL(hid_hw_close);
2053
2054struct hid_dynid {
2055	struct list_head list;
2056	struct hid_device_id id;
2057};
2058
2059/**
2060 * store_new_id - add a new HID device ID to this driver and re-probe devices
2061 * @driver: target device driver
2062 * @buf: buffer for scanning device ID data
2063 * @count: input size
2064 *
2065 * Adds a new dynamic hid device ID to this driver,
2066 * and causes the driver to probe for all devices again.
2067 */
2068static ssize_t new_id_store(struct device_driver *drv, const char *buf,
2069		size_t count)
2070{
2071	struct hid_driver *hdrv = to_hid_driver(drv);
2072	struct hid_dynid *dynid;
2073	__u32 bus, vendor, product;
2074	unsigned long driver_data = 0;
2075	int ret;
2076
2077	ret = sscanf(buf, "%x %x %x %lx",
2078			&bus, &vendor, &product, &driver_data);
2079	if (ret < 3)
2080		return -EINVAL;
2081
2082	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
2083	if (!dynid)
2084		return -ENOMEM;
2085
2086	dynid->id.bus = bus;
2087	dynid->id.group = HID_GROUP_ANY;
2088	dynid->id.vendor = vendor;
2089	dynid->id.product = product;
2090	dynid->id.driver_data = driver_data;
2091
2092	spin_lock(&hdrv->dyn_lock);
2093	list_add_tail(&dynid->list, &hdrv->dyn_list);
2094	spin_unlock(&hdrv->dyn_lock);
2095
2096	ret = driver_attach(&hdrv->driver);
 
 
 
 
2097
2098	return ret ? : count;
2099}
2100static DRIVER_ATTR_WO(new_id);
2101
2102static struct attribute *hid_drv_attrs[] = {
2103	&driver_attr_new_id.attr,
2104	NULL,
2105};
2106ATTRIBUTE_GROUPS(hid_drv);
2107
2108static void hid_free_dynids(struct hid_driver *hdrv)
2109{
2110	struct hid_dynid *dynid, *n;
2111
2112	spin_lock(&hdrv->dyn_lock);
2113	list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
2114		list_del(&dynid->list);
2115		kfree(dynid);
2116	}
2117	spin_unlock(&hdrv->dyn_lock);
2118}
2119
2120const struct hid_device_id *hid_match_device(struct hid_device *hdev,
2121					     struct hid_driver *hdrv)
2122{
2123	struct hid_dynid *dynid;
2124
2125	spin_lock(&hdrv->dyn_lock);
2126	list_for_each_entry(dynid, &hdrv->dyn_list, list) {
2127		if (hid_match_one_id(hdev, &dynid->id)) {
2128			spin_unlock(&hdrv->dyn_lock);
2129			return &dynid->id;
2130		}
2131	}
2132	spin_unlock(&hdrv->dyn_lock);
2133
2134	return hid_match_id(hdev, hdrv->id_table);
2135}
2136EXPORT_SYMBOL_GPL(hid_match_device);
2137
2138static int hid_bus_match(struct device *dev, struct device_driver *drv)
2139{
2140	struct hid_driver *hdrv = to_hid_driver(drv);
2141	struct hid_device *hdev = to_hid_device(dev);
2142
2143	return hid_match_device(hdev, hdrv) != NULL;
2144}
2145
2146/**
2147 * hid_compare_device_paths - check if both devices share the same path
2148 * @hdev_a: hid device
2149 * @hdev_b: hid device
2150 * @separator: char to use as separator
2151 *
2152 * Check if two devices share the same path up to the last occurrence of
2153 * the separator char. Both paths must exist (i.e., zero-length paths
2154 * don't match).
2155 */
2156bool hid_compare_device_paths(struct hid_device *hdev_a,
2157			      struct hid_device *hdev_b, char separator)
2158{
2159	int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
2160	int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
2161
2162	if (n1 != n2 || n1 <= 0 || n2 <= 0)
2163		return false;
 
2164
2165	return !strncmp(hdev_a->phys, hdev_b->phys, n1);
2166}
2167EXPORT_SYMBOL_GPL(hid_compare_device_paths);
2168
2169static int hid_device_probe(struct device *dev)
2170{
2171	struct hid_driver *hdrv = to_hid_driver(dev->driver);
2172	struct hid_device *hdev = to_hid_device(dev);
 
2173	const struct hid_device_id *id;
2174	int ret = 0;
2175
2176	if (down_interruptible(&hdev->driver_input_lock)) {
2177		ret = -EINTR;
2178		goto end;
2179	}
2180	hdev->io_started = false;
2181
2182	clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
2183
2184	if (!hdev->driver) {
2185		id = hid_match_device(hdev, hdrv);
2186		if (id == NULL) {
2187			ret = -ENODEV;
2188			goto unlock;
2189		}
2190
2191		if (hdrv->match) {
2192			if (!hdrv->match(hdev, hid_ignore_special_drivers)) {
2193				ret = -ENODEV;
2194				goto unlock;
2195			}
2196		} else {
2197			/*
2198			 * hid-generic implements .match(), so if
2199			 * hid_ignore_special_drivers is set, we can safely
2200			 * return.
2201			 */
2202			if (hid_ignore_special_drivers) {
2203				ret = -ENODEV;
2204				goto unlock;
2205			}
2206		}
2207
2208		/* reset the quirks that has been previously set */
2209		hdev->quirks = hid_lookup_quirk(hdev);
2210		hdev->driver = hdrv;
2211		if (hdrv->probe) {
2212			ret = hdrv->probe(hdev, id);
2213		} else { /* default probe */
2214			ret = hid_open_report(hdev);
2215			if (!ret)
2216				ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
2217		}
2218		if (ret) {
2219			hid_close_report(hdev);
2220			hdev->driver = NULL;
2221		}
2222	}
2223unlock:
2224	if (!hdev->io_started)
2225		up(&hdev->driver_input_lock);
2226end:
2227	return ret;
2228}
2229
2230static int hid_device_remove(struct device *dev)
2231{
2232	struct hid_device *hdev = to_hid_device(dev);
2233	struct hid_driver *hdrv;
2234	int ret = 0;
2235
2236	if (down_interruptible(&hdev->driver_input_lock)) {
2237		ret = -EINTR;
2238		goto end;
2239	}
2240	hdev->io_started = false;
2241
2242	hdrv = hdev->driver;
2243	if (hdrv) {
2244		if (hdrv->remove)
2245			hdrv->remove(hdev);
2246		else /* default remove */
2247			hid_hw_stop(hdev);
2248		hid_close_report(hdev);
2249		hdev->driver = NULL;
2250	}
2251
2252	if (!hdev->io_started)
2253		up(&hdev->driver_input_lock);
2254end:
2255	return ret;
2256}
2257
2258static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
2259			     char *buf)
2260{
2261	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
2262
2263	return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n",
2264			 hdev->bus, hdev->group, hdev->vendor, hdev->product);
2265}
2266static DEVICE_ATTR_RO(modalias);
2267
2268static struct attribute *hid_dev_attrs[] = {
2269	&dev_attr_modalias.attr,
2270	NULL,
2271};
2272static struct bin_attribute *hid_dev_bin_attrs[] = {
2273	&dev_bin_attr_report_desc,
2274	NULL
2275};
2276static const struct attribute_group hid_dev_group = {
2277	.attrs = hid_dev_attrs,
2278	.bin_attrs = hid_dev_bin_attrs,
2279};
2280__ATTRIBUTE_GROUPS(hid_dev);
2281
2282static int hid_uevent(struct device *dev, struct kobj_uevent_env *env)
2283{
2284	struct hid_device *hdev = to_hid_device(dev);
2285
2286	if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
2287			hdev->bus, hdev->vendor, hdev->product))
2288		return -ENOMEM;
2289
2290	if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
2291		return -ENOMEM;
2292
2293	if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
2294		return -ENOMEM;
2295
2296	if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
2297		return -ENOMEM;
2298
2299	if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
2300			   hdev->bus, hdev->group, hdev->vendor, hdev->product))
2301		return -ENOMEM;
2302
2303	return 0;
2304}
2305
2306struct bus_type hid_bus_type = {
2307	.name		= "hid",
2308	.dev_groups	= hid_dev_groups,
2309	.drv_groups	= hid_drv_groups,
2310	.match		= hid_bus_match,
2311	.probe		= hid_device_probe,
2312	.remove		= hid_device_remove,
2313	.uevent		= hid_uevent,
2314};
2315EXPORT_SYMBOL(hid_bus_type);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2316
2317int hid_add_device(struct hid_device *hdev)
2318{
2319	static atomic_t id = ATOMIC_INIT(0);
2320	int ret;
2321
2322	if (WARN_ON(hdev->status & HID_STAT_ADDED))
2323		return -EBUSY;
2324
2325	hdev->quirks = hid_lookup_quirk(hdev);
2326
2327	/* we need to kill them here, otherwise they will stay allocated to
2328	 * wait for coming driver */
2329	if (hid_ignore(hdev))
 
2330		return -ENODEV;
2331
2332	/*
2333	 * Check for the mandatory transport channel.
2334	 */
2335	 if (!hdev->ll_driver->raw_request) {
2336		hid_err(hdev, "transport driver missing .raw_request()\n");
2337		return -EINVAL;
2338	 }
2339
2340	/*
2341	 * Read the device report descriptor once and use as template
2342	 * for the driver-specific modifications.
2343	 */
2344	ret = hdev->ll_driver->parse(hdev);
2345	if (ret)
2346		return ret;
2347	if (!hdev->dev_rdesc)
2348		return -ENODEV;
2349
2350	/*
2351	 * Scan generic devices for group information
2352	 */
2353	if (hid_ignore_special_drivers) {
2354		hdev->group = HID_GROUP_GENERIC;
2355	} else if (!hdev->group &&
2356		   !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
2357		ret = hid_scan_report(hdev);
2358		if (ret)
2359			hid_warn(hdev, "bad device descriptor (%d)\n", ret);
2360	}
2361
2362	/* XXX hack, any other cleaner solution after the driver core
2363	 * is converted to allow more than 20 bytes as the device name? */
2364	dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
2365		     hdev->vendor, hdev->product, atomic_inc_return(&id));
2366
2367	hid_debug_register(hdev, dev_name(&hdev->dev));
2368	ret = device_add(&hdev->dev);
2369	if (!ret)
2370		hdev->status |= HID_STAT_ADDED;
2371	else
2372		hid_debug_unregister(hdev);
2373
2374	return ret;
2375}
2376EXPORT_SYMBOL_GPL(hid_add_device);
2377
2378/**
2379 * hid_allocate_device - allocate new hid device descriptor
2380 *
2381 * Allocate and initialize hid device, so that hid_destroy_device might be
2382 * used to free it.
2383 *
2384 * New hid_device pointer is returned on success, otherwise ERR_PTR encoded
2385 * error value.
2386 */
2387struct hid_device *hid_allocate_device(void)
2388{
2389	struct hid_device *hdev;
 
2390	int ret = -ENOMEM;
2391
2392	hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
2393	if (hdev == NULL)
2394		return ERR_PTR(ret);
2395
2396	device_initialize(&hdev->dev);
2397	hdev->dev.release = hid_device_release;
2398	hdev->dev.bus = &hid_bus_type;
2399	device_enable_async_suspend(&hdev->dev);
2400
2401	hid_close_report(hdev);
 
 
 
 
 
 
 
2402
2403	init_waitqueue_head(&hdev->debug_wait);
2404	INIT_LIST_HEAD(&hdev->debug_list);
2405	spin_lock_init(&hdev->debug_list_lock);
2406	sema_init(&hdev->driver_input_lock, 1);
2407	mutex_init(&hdev->ll_open_lock);
2408
2409	return hdev;
 
 
 
2410}
2411EXPORT_SYMBOL_GPL(hid_allocate_device);
2412
2413static void hid_remove_device(struct hid_device *hdev)
2414{
2415	if (hdev->status & HID_STAT_ADDED) {
2416		device_del(&hdev->dev);
2417		hid_debug_unregister(hdev);
2418		hdev->status &= ~HID_STAT_ADDED;
2419	}
2420	kfree(hdev->dev_rdesc);
2421	hdev->dev_rdesc = NULL;
2422	hdev->dev_rsize = 0;
2423}
2424
2425/**
2426 * hid_destroy_device - free previously allocated device
2427 *
2428 * @hdev: hid device
2429 *
2430 * If you allocate hid_device through hid_allocate_device, you should ever
2431 * free by this function.
2432 */
2433void hid_destroy_device(struct hid_device *hdev)
2434{
2435	hid_remove_device(hdev);
2436	put_device(&hdev->dev);
2437}
2438EXPORT_SYMBOL_GPL(hid_destroy_device);
2439
2440
2441static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
2442{
2443	struct hid_driver *hdrv = data;
2444	struct hid_device *hdev = to_hid_device(dev);
2445
2446	if (hdev->driver == hdrv &&
2447	    !hdrv->match(hdev, hid_ignore_special_drivers) &&
2448	    !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
2449		return device_reprobe(dev);
2450
2451	return 0;
2452}
2453
2454static int __hid_bus_driver_added(struct device_driver *drv, void *data)
2455{
2456	struct hid_driver *hdrv = to_hid_driver(drv);
2457
2458	if (hdrv->match) {
2459		bus_for_each_dev(&hid_bus_type, NULL, hdrv,
2460				 __hid_bus_reprobe_drivers);
2461	}
2462
2463	return 0;
2464}
2465
2466static int __bus_removed_driver(struct device_driver *drv, void *data)
2467{
2468	return bus_rescan_devices(&hid_bus_type);
2469}
2470
2471int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
2472		const char *mod_name)
2473{
2474	int ret;
2475
2476	hdrv->driver.name = hdrv->name;
2477	hdrv->driver.bus = &hid_bus_type;
2478	hdrv->driver.owner = owner;
2479	hdrv->driver.mod_name = mod_name;
2480
2481	INIT_LIST_HEAD(&hdrv->dyn_list);
2482	spin_lock_init(&hdrv->dyn_lock);
2483
2484	ret = driver_register(&hdrv->driver);
 
 
2485
2486	if (ret == 0)
2487		bus_for_each_drv(&hid_bus_type, NULL, NULL,
2488				 __hid_bus_driver_added);
2489
2490	return ret;
2491}
2492EXPORT_SYMBOL_GPL(__hid_register_driver);
2493
2494void hid_unregister_driver(struct hid_driver *hdrv)
2495{
 
2496	driver_unregister(&hdrv->driver);
2497	hid_free_dynids(hdrv);
2498
2499	bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
2500}
2501EXPORT_SYMBOL_GPL(hid_unregister_driver);
2502
2503int hid_check_keys_pressed(struct hid_device *hid)
2504{
2505	struct hid_input *hidinput;
2506	int i;
2507
2508	if (!(hid->claimed & HID_CLAIMED_INPUT))
2509		return 0;
2510
2511	list_for_each_entry(hidinput, &hid->inputs, list) {
2512		for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
2513			if (hidinput->input->key[i])
2514				return 1;
2515	}
2516
2517	return 0;
2518}
2519
2520EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
2521
2522static int __init hid_init(void)
2523{
2524	int ret;
2525
2526	if (hid_debug)
2527		pr_warn("hid_debug is now used solely for parser and driver debugging.\n"
2528			"debugfs is now used for inspecting the device (report descriptor, reports)\n");
2529
2530	ret = bus_register(&hid_bus_type);
2531	if (ret) {
2532		pr_err("can't register hid bus\n");
2533		goto err;
2534	}
2535
2536	ret = hidraw_init();
2537	if (ret)
2538		goto err_bus;
2539
2540	hid_debug_init();
2541
2542	return 0;
2543err_bus:
2544	bus_unregister(&hid_bus_type);
2545err:
2546	return ret;
2547}
2548
2549static void __exit hid_exit(void)
2550{
2551	hid_debug_exit();
2552	hidraw_exit();
2553	bus_unregister(&hid_bus_type);
2554	hid_quirks_exit(HID_BUS_ANY);
2555}
2556
2557module_init(hid_init);
2558module_exit(hid_exit);
2559
2560MODULE_AUTHOR("Andreas Gal");
2561MODULE_AUTHOR("Vojtech Pavlik");
2562MODULE_AUTHOR("Jiri Kosina");
2563MODULE_LICENSE("GPL");