drivers/hid/hid-core.c

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