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