drivers/hid/hid-core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  HID support for Linux
   4  *
   5  *  Copyright (c) 1999 Andreas Gal
   6  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
   7  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
   8  *  Copyright (c) 2006-2012 Jiri Kosina
   9  */
  10
  11 /*
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/list.h>
  21 #include <linux/mm.h>
  22 #include <linux/spinlock.h>
  23 #include <asm/unaligned.h>
  24 #include <asm/byteorder.h>
  25 #include <linux/input.h>
  26 #include <linux/wait.h>
  27 #include <linux/vmalloc.h>
  28 #include <linux/sched.h>
  29 #include <linux/semaphore.h>
  30
  31 #include <linux/hid.h>
  32 #include <linux/hiddev.h>
  33 #include <linux/hid-debug.h>
  34 #include <linux/hidraw.h>
  35
  36 #include "hid-ids.h"
  37
  38 /*
  39  * Version Information
  40  */
  41
  42 #define DRIVER_DESC "HID core driver"
  43
  44 static int hid_ignore_special_drivers = 0;
  45 module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
  46 MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
  47
  48 /*
  49  * Register a new report for a device.
  50  */
  51
  52 struct hid_report *hid_register_report(struct hid_device *device,
  53                                        enum hid_report_type type, unsigned int id,
  54                                        unsigned int application)
  55 {
  56         struct hid_report_enum *report_enum = device->report_enum + type;
  57         struct hid_report *report;
  58
  59         if (id >= HID_MAX_IDS)
  60                 return NULL;
  61         if (report_enum->report_id_hash[id])
  62                 return report_enum->report_id_hash[id];
  63
  64         report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
  65         if (!report)
  66                 return NULL;
  67
  68         if (id != 0)
  69                 report_enum->numbered = 1;
  70
  71         report->id = id;
  72         report->type = type;
  73         report->size = 0;
  74         report->device = device;
  75         report->application = application;
  76         report_enum->report_id_hash[id] = report;
  77
  78         list_add_tail(&report->list, &report_enum->report_list);
  79         INIT_LIST_HEAD(&report->field_entry_list);
  80
  81         return report;
  82 }
  83 EXPORT_SYMBOL_GPL(hid_register_report);
  84
  85 /*
  86  * Register a new field for this report.
  87  */
  88
  89 static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages)
  90 {
  91         struct hid_field *field;
  92
  93         if (report->maxfield == HID_MAX_FIELDS) {
  94                 hid_err(report->device, "too many fields in report\n");
  95                 return NULL;
  96         }
  97
  98         field = kzalloc((sizeof(struct hid_field) +
  99                          usages * sizeof(struct hid_usage) +
 100                          3 * usages * sizeof(unsigned int)), GFP_KERNEL);
 101         if (!field)
 102                 return NULL;
 103
 104         field->index = report->maxfield++;
 105         report->field[field->index] = field;
 106         field->usage = (struct hid_usage *)(field + 1);
 107         field->value = (s32 *)(field->usage + usages);
 108         field->new_value = (s32 *)(field->value + usages);
 109         field->usages_priorities = (s32 *)(field->new_value + usages);
 110         field->report = report;
 111
 112         return field;
 113 }
 114
 115 /*
 116  * Open a collection. The type/usage is pushed on the stack.
 117  */
 118
 119 static int open_collection(struct hid_parser *parser, unsigned type)
 120 {
 121         struct hid_collection *collection;
 122         unsigned usage;
 123         int collection_index;
 124
 125         usage = parser->local.usage[0];
 126
 127         if (parser->collection_stack_ptr == parser->collection_stack_size) {
 128                 unsigned int *collection_stack;
 129                 unsigned int new_size = parser->collection_stack_size +
 130                                         HID_COLLECTION_STACK_SIZE;
 131
 132                 collection_stack = krealloc(parser->collection_stack,
 133                                             new_size * sizeof(unsigned int),
 134                                             GFP_KERNEL);
 135                 if (!collection_stack)
 136                         return -ENOMEM;
 137
 138                 parser->collection_stack = collection_stack;
 139                 parser->collection_stack_size = new_size;
 140         }
 141
 142         if (parser->device->maxcollection == parser->device->collection_size) {
 143                 collection = kmalloc(
 144                                 array3_size(sizeof(struct hid_collection),
 145                                             parser->device->collection_size,
 146                                             2),
 147                                 GFP_KERNEL);
 148                 if (collection == NULL) {
 149                         hid_err(parser->device, "failed to reallocate collection array\n");
 150                         return -ENOMEM;
 151                 }
 152                 memcpy(collection, parser->device->collection,
 153                         sizeof(struct hid_collection) *
 154                         parser->device->collection_size);
 155                 memset(collection + parser->device->collection_size, 0,
 156                         sizeof(struct hid_collection) *
 157                         parser->device->collection_size);
 158                 kfree(parser->device->collection);
 159                 parser->device->collection = collection;
 160                 parser->device->collection_size *= 2;
 161         }
 162
 163         parser->collection_stack[parser->collection_stack_ptr++] =
 164                 parser->device->maxcollection;
 165
 166         collection_index = parser->device->maxcollection++;
 167         collection = parser->device->collection + collection_index;
 168         collection->type = type;
 169         collection->usage = usage;
 170         collection->level = parser->collection_stack_ptr - 1;
 171         collection->parent_idx = (collection->level == 0) ? -1 :
 172                 parser->collection_stack[collection->level - 1];
 173
 174         if (type == HID_COLLECTION_APPLICATION)
 175                 parser->device->maxapplication++;
 176
 177         return 0;
 178 }
 179
 180 /*
 181  * Close a collection.
 182  */
 183
 184 static int close_collection(struct hid_parser *parser)
 185 {
 186         if (!parser->collection_stack_ptr) {
 187                 hid_err(parser->device, "collection stack underflow\n");
 188                 return -EINVAL;
 189         }
 190         parser->collection_stack_ptr--;
 191         return 0;
 192 }
 193
 194 /*
 195  * Climb up the stack, search for the specified collection type
 196  * and return the usage.
 197  */
 198
 199 static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
 200 {
 201         struct hid_collection *collection = parser->device->collection;
 202         int n;
 203
 204         for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
 205                 unsigned index = parser->collection_stack[n];
 206                 if (collection[index].type == type)
 207                         return collection[index].usage;
 208         }
 209         return 0; /* we know nothing about this usage type */
 210 }
 211
 212 /*
 213  * Concatenate usage which defines 16 bits or less with the
 214  * currently defined usage page to form a 32 bit usage
 215  */
 216
 217 static void complete_usage(struct hid_parser *parser, unsigned int index)
 218 {
 219         parser->local.usage[index] &= 0xFFFF;
 220         parser->local.usage[index] |=
 221                 (parser->global.usage_page & 0xFFFF) << 16;
 222 }
 223
 224 /*
 225  * Add a usage to the temporary parser table.
 226  */
 227
 228 static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
 229 {
 230         if (parser->local.usage_index >= HID_MAX_USAGES) {
 231                 hid_err(parser->device, "usage index exceeded\n");
 232                 return -1;
 233         }
 234         parser->local.usage[parser->local.usage_index] = usage;
 235
 236         /*
 237          * If Usage item only includes usage id, concatenate it with
 238          * currently defined usage page
 239          */
 240         if (size <= 2)
 241                 complete_usage(parser, parser->local.usage_index);
 242
 243         parser->local.usage_size[parser->local.usage_index] = size;
 244         parser->local.collection_index[parser->local.usage_index] =
 245                 parser->collection_stack_ptr ?
 246                 parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
 247         parser->local.usage_index++;
 248         return 0;
 249 }
 250
 251 /*
 252  * Register a new field for this report.
 253  */
 254
 255 static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
 256 {
 257         struct hid_report *report;
 258         struct hid_field *field;
 259         unsigned int usages;
 260         unsigned int offset;
 261         unsigned int i;
 262         unsigned int application;
 263
 264         application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
 265
 266         report = hid_register_report(parser->device, report_type,
 267                                      parser->global.report_id, application);
 268         if (!report) {
 269                 hid_err(parser->device, "hid_register_report failed\n");
 270                 return -1;
 271         }
 272
 273         /* Handle both signed and unsigned cases properly */
 274         if ((parser->global.logical_minimum < 0 &&
 275                 parser->global.logical_maximum <
 276                 parser->global.logical_minimum) ||
 277                 (parser->global.logical_minimum >= 0 &&
 278                 (__u32)parser->global.logical_maximum <
 279                 (__u32)parser->global.logical_minimum)) {
 280                 dbg_hid("logical range invalid 0x%x 0x%x\n",
 281                         parser->global.logical_minimum,
 282                         parser->global.logical_maximum);
 283                 return -1;
 284         }
 285
 286         offset = report->size;
 287         report->size += parser->global.report_size * parser->global.report_count;
 288
 289         /* Total size check: Allow for possible report index byte */
 290         if (report->size > (HID_MAX_BUFFER_SIZE - 1) << 3) {
 291                 hid_err(parser->device, "report is too long\n");
 292                 return -1;
 293         }
 294
 295         if (!parser->local.usage_index) /* Ignore padding fields */
 296                 return 0;
 297
 298         usages = max_t(unsigned, parser->local.usage_index,
 299                                  parser->global.report_count);
 300
 301         field = hid_register_field(report, usages);
 302         if (!field)
 303                 return 0;
 304
 305         field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
 306         field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
 307         field->application = application;
 308
 309         for (i = 0; i < usages; i++) {
 310                 unsigned j = i;
 311                 /* Duplicate the last usage we parsed if we have excess values */
 312                 if (i >= parser->local.usage_index)
 313                         j = parser->local.usage_index - 1;
 314                 field->usage[i].hid = parser->local.usage[j];
 315                 field->usage[i].collection_index =
 316                         parser->local.collection_index[j];
 317                 field->usage[i].usage_index = i;
 318                 field->usage[i].resolution_multiplier = 1;
 319         }
 320
 321         field->maxusage = usages;
 322         field->flags = flags;
 323         field->report_offset = offset;
 324         field->report_type = report_type;
 325         field->report_size = parser->global.report_size;
 326         field->report_count = parser->global.report_count;
 327         field->logical_minimum = parser->global.logical_minimum;
 328         field->logical_maximum = parser->global.logical_maximum;
 329         field->physical_minimum = parser->global.physical_minimum;
 330         field->physical_maximum = parser->global.physical_maximum;
 331         field->unit_exponent = parser->global.unit_exponent;
 332         field->unit = parser->global.unit;
 333
 334         return 0;
 335 }
 336
 337 /*
 338  * Read data value from item.
 339  */
 340
 341 static u32 item_udata(struct hid_item *item)
 342 {
 343         switch (item->size) {
 344         case 1: return item->data.u8;
 345         case 2: return item->data.u16;
 346         case 4: return item->data.u32;
 347         }
 348         return 0;
 349 }
 350
 351 static s32 item_sdata(struct hid_item *item)
 352 {
 353         switch (item->size) {
 354         case 1: return item->data.s8;
 355         case 2: return item->data.s16;
 356         case 4: return item->data.s32;
 357         }
 358         return 0;
 359 }
 360
 361 /*
 362  * Process a global item.
 363  */
 364
 365 static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 366 {
 367         __s32 raw_value;
 368         switch (item->tag) {
 369         case HID_GLOBAL_ITEM_TAG_PUSH:
 370
 371                 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
 372                         hid_err(parser->device, "global environment stack overflow\n");
 373                         return -1;
 374                 }
 375
 376                 memcpy(parser->global_stack + parser->global_stack_ptr++,
 377                         &parser->global, sizeof(struct hid_global));
 378                 return 0;
 379
 380         case HID_GLOBAL_ITEM_TAG_POP:
 381
 382                 if (!parser->global_stack_ptr) {
 383                         hid_err(parser->device, "global environment stack underflow\n");
 384                         return -1;
 385                 }
 386
 387                 memcpy(&parser->global, parser->global_stack +
 388                         --parser->global_stack_ptr, sizeof(struct hid_global));
 389                 return 0;
 390
 391         case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
 392                 parser->global.usage_page = item_udata(item);
 393                 return 0;
 394
 395         case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
 396                 parser->global.logical_minimum = item_sdata(item);
 397                 return 0;
 398
 399         case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
 400                 if (parser->global.logical_minimum < 0)
 401                         parser->global.logical_maximum = item_sdata(item);
 402                 else
 403                         parser->global.logical_maximum = item_udata(item);
 404                 return 0;
 405
 406         case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
 407                 parser->global.physical_minimum = item_sdata(item);
 408                 return 0;
 409
 410         case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
 411                 if (parser->global.physical_minimum < 0)
 412                         parser->global.physical_maximum = item_sdata(item);
 413                 else
 414                         parser->global.physical_maximum = item_udata(item);
 415                 return 0;
 416
 417         case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
 418                 /* Many devices provide unit exponent as a two's complement
 419                  * nibble due to the common misunderstanding of HID
 420                  * specification 1.11, 6.2.2.7 Global Items. Attempt to handle
 421                  * both this and the standard encoding. */
 422                 raw_value = item_sdata(item);
 423                 if (!(raw_value & 0xfffffff0))
 424                         parser->global.unit_exponent = hid_snto32(raw_value, 4);
 425                 else
 426                         parser->global.unit_exponent = raw_value;
 427                 return 0;
 428
 429         case HID_GLOBAL_ITEM_TAG_UNIT:
 430                 parser->global.unit = item_udata(item);
 431                 return 0;
 432
 433         case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
 434                 parser->global.report_size = item_udata(item);
 435                 if (parser->global.report_size > 256) {
 436                         hid_err(parser->device, "invalid report_size %d\n",
 437                                         parser->global.report_size);
 438                         return -1;
 439                 }
 440                 return 0;
 441
 442         case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
 443                 parser->global.report_count = item_udata(item);
 444                 if (parser->global.report_count > HID_MAX_USAGES) {
 445                         hid_err(parser->device, "invalid report_count %d\n",
 446                                         parser->global.report_count);
 447                         return -1;
 448                 }
 449                 return 0;
 450
 451         case HID_GLOBAL_ITEM_TAG_REPORT_ID:
 452                 parser->global.report_id = item_udata(item);
 453                 if (parser->global.report_id == 0 ||
 454                     parser->global.report_id >= HID_MAX_IDS) {
 455                         hid_err(parser->device, "report_id %u is invalid\n",
 456                                 parser->global.report_id);
 457                         return -1;
 458                 }
 459                 return 0;
 460
 461         default:
 462                 hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
 463                 return -1;
 464         }
 465 }
 466
 467 /*
 468  * Process a local item.
 469  */
 470
 471 static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 472 {
 473         __u32 data;
 474         unsigned n;
 475         __u32 count;
 476
 477         data = item_udata(item);
 478
 479         switch (item->tag) {
 480         case HID_LOCAL_ITEM_TAG_DELIMITER:
 481
 482                 if (data) {
 483                         /*
 484                          * We treat items before the first delimiter
 485                          * as global to all usage sets (branch 0).
 486                          * In the moment we process only these global
 487                          * items and the first delimiter set.
 488                          */
 489                         if (parser->local.delimiter_depth != 0) {
 490                                 hid_err(parser->device, "nested delimiters\n");
 491                                 return -1;
 492                         }
 493                         parser->local.delimiter_depth++;
 494                         parser->local.delimiter_branch++;
 495                 } else {
 496                         if (parser->local.delimiter_depth < 1) {
 497                                 hid_err(parser->device, "bogus close delimiter\n");
 498                                 return -1;
 499                         }
 500                         parser->local.delimiter_depth--;
 501                 }
 502                 return 0;
 503
 504         case HID_LOCAL_ITEM_TAG_USAGE:
 505
 506                 if (parser->local.delimiter_branch > 1) {
 507                         dbg_hid("alternative usage ignored\n");
 508                         return 0;
 509                 }
 510
 511                 return hid_add_usage(parser, data, item->size);
 512
 513         case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
 514
 515                 if (parser->local.delimiter_branch > 1) {
 516                         dbg_hid("alternative usage ignored\n");
 517                         return 0;
 518                 }
 519
 520                 parser->local.usage_minimum = data;
 521                 return 0;
 522
 523         case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
 524
 525                 if (parser->local.delimiter_branch > 1) {
 526                         dbg_hid("alternative usage ignored\n");
 527                         return 0;
 528                 }
 529
 530                 count = data - parser->local.usage_minimum;
 531                 if (count + parser->local.usage_index >= HID_MAX_USAGES) {
 532                         /*
 533                          * We do not warn if the name is not set, we are
 534                          * actually pre-scanning the device.
 535                          */
 536                         if (dev_name(&parser->device->dev))
 537                                 hid_warn(parser->device,
 538                                          "ignoring exceeding usage max\n");
 539                         data = HID_MAX_USAGES - parser->local.usage_index +
 540                                 parser->local.usage_minimum - 1;
 541                         if (data <= 0) {
 542                                 hid_err(parser->device,
 543                                         "no more usage index available\n");
 544                                 return -1;
 545                         }
 546                 }
 547
 548                 for (n = parser->local.usage_minimum; n <= data; n++)
 549                         if (hid_add_usage(parser, n, item->size)) {
 550                                 dbg_hid("hid_add_usage failed\n");
 551                                 return -1;
 552                         }
 553                 return 0;
 554
 555         default:
 556
 557                 dbg_hid("unknown local item tag 0x%x\n", item->tag);
 558                 return 0;
 559         }
 560         return 0;
 561 }
 562
 563 /*
 564  * Concatenate Usage Pages into Usages where relevant:
 565  * As per specification, 6.2.2.8: "When the parser encounters a main item it
 566  * concatenates the last declared Usage Page with a Usage to form a complete
 567  * usage value."
 568  */
 569
 570 static void hid_concatenate_last_usage_page(struct hid_parser *parser)
 571 {
 572         int i;
 573         unsigned int usage_page;
 574         unsigned int current_page;
 575
 576         if (!parser->local.usage_index)
 577                 return;
 578
 579         usage_page = parser->global.usage_page;
 580
 581         /*
 582          * Concatenate usage page again only if last declared Usage Page
 583          * has not been already used in previous usages concatenation
 584          */
 585         for (i = parser->local.usage_index - 1; i >= 0; i--) {
 586                 if (parser->local.usage_size[i] > 2)
 587                         /* Ignore extended usages */
 588                         continue;
 589
 590                 current_page = parser->local.usage[i] >> 16;
 591                 if (current_page == usage_page)
 592                         break;
 593
 594                 complete_usage(parser, i);
 595         }
 596 }
 597
 598 /*
 599  * Process a main item.
 600  */
 601
 602 static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
 603 {
 604         __u32 data;
 605         int ret;
 606
 607         hid_concatenate_last_usage_page(parser);
 608
 609         data = item_udata(item);
 610
 611         switch (item->tag) {
 612         case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 613                 ret = open_collection(parser, data & 0xff);
 614                 break;
 615         case HID_MAIN_ITEM_TAG_END_COLLECTION:
 616                 ret = close_collection(parser);
 617                 break;
 618         case HID_MAIN_ITEM_TAG_INPUT:
 619                 ret = hid_add_field(parser, HID_INPUT_REPORT, data);
 620                 break;
 621         case HID_MAIN_ITEM_TAG_OUTPUT:
 622                 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
 623                 break;
 624         case HID_MAIN_ITEM_TAG_FEATURE:
 625                 ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
 626                 break;
 627         default:
 628                 hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag);
 629                 ret = 0;
 630         }
 631
 632         memset(&parser->local, 0, sizeof(parser->local));       /* Reset the local parser environment */
 633
 634         return ret;
 635 }
 636
 637 /*
 638  * Process a reserved item.
 639  */
 640
 641 static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
 642 {
 643         dbg_hid("reserved item type, tag 0x%x\n", item->tag);
 644         return 0;
 645 }
 646
 647 /*
 648  * Free a report and all registered fields. The field->usage and
 649  * field->value table's are allocated behind the field, so we need
 650  * only to free(field) itself.
 651  */
 652
 653 static void hid_free_report(struct hid_report *report)
 654 {
 655         unsigned n;
 656
 657         kfree(report->field_entries);
 658
 659         for (n = 0; n < report->maxfield; n++)
 660                 kfree(report->field[n]);
 661         kfree(report);
 662 }
 663
 664 /*
 665  * Close report. This function returns the device
 666  * state to the point prior to hid_open_report().
 667  */
 668 static void hid_close_report(struct hid_device *device)
 669 {
 670         unsigned i, j;
 671
 672         for (i = 0; i < HID_REPORT_TYPES; i++) {
 673                 struct hid_report_enum *report_enum = device->report_enum + i;
 674
 675                 for (j = 0; j < HID_MAX_IDS; j++) {
 676                         struct hid_report *report = report_enum->report_id_hash[j];
 677                         if (report)
 678                                 hid_free_report(report);
 679                 }
 680                 memset(report_enum, 0, sizeof(*report_enum));
 681                 INIT_LIST_HEAD(&report_enum->report_list);
 682         }
 683
 684         kfree(device->rdesc);
 685         device->rdesc = NULL;
 686         device->rsize = 0;
 687
 688         kfree(device->collection);
 689         device->collection = NULL;
 690         device->collection_size = 0;
 691         device->maxcollection = 0;
 692         device->maxapplication = 0;
 693
 694         device->status &= ~HID_STAT_PARSED;
 695 }
 696
 697 /*
 698  * Free a device structure, all reports, and all fields.
 699  */
 700
 701 static void hid_device_release(struct device *dev)
 702 {
 703         struct hid_device *hid = to_hid_device(dev);
 704
 705         hid_close_report(hid);
 706         kfree(hid->dev_rdesc);
 707         kfree(hid);
 708 }
 709
 710 /*
 711  * Fetch a report description item from the data stream. We support long
 712  * items, though they are not used yet.
 713  */
 714
 715 static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
 716 {
 717         u8 b;
 718
 719         if ((end - start) <= 0)
 720                 return NULL;
 721
 722         b = *start++;
 723
 724         item->type = (b >> 2) & 3;
 725         item->tag  = (b >> 4) & 15;
 726
 727         if (item->tag == HID_ITEM_TAG_LONG) {
 728
 729                 item->format = HID_ITEM_FORMAT_LONG;
 730
 731                 if ((end - start) < 2)
 732                         return NULL;
 733
 734                 item->size = *start++;
 735                 item->tag  = *start++;
 736
 737                 if ((end - start) < item->size)
 738                         return NULL;
 739
 740                 item->data.longdata = start;
 741                 start += item->size;
 742                 return start;
 743         }
 744
 745         item->format = HID_ITEM_FORMAT_SHORT;
 746         item->size = b & 3;
 747
 748         switch (item->size) {
 749         case 0:
 750                 return start;
 751
 752         case 1:
 753                 if ((end - start) < 1)
 754                         return NULL;
 755                 item->data.u8 = *start++;
 756                 return start;
 757
 758         case 2:
 759                 if ((end - start) < 2)
 760                         return NULL;
 761                 item->data.u16 = get_unaligned_le16(start);
 762                 start = (__u8 *)((__le16 *)start + 1);
 763                 return start;
 764
 765         case 3:
 766                 item->size++;
 767                 if ((end - start) < 4)
 768                         return NULL;
 769                 item->data.u32 = get_unaligned_le32(start);
 770                 start = (__u8 *)((__le32 *)start + 1);
 771                 return start;
 772         }
 773
 774         return NULL;
 775 }
 776
 777 static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
 778 {
 779         struct hid_device *hid = parser->device;
 780
 781         if (usage == HID_DG_CONTACTID)
 782                 hid->group = HID_GROUP_MULTITOUCH;
 783 }
 784
 785 static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
 786 {
 787         if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
 788             parser->global.report_size == 8)
 789                 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 790
 791         if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
 792             parser->global.report_size == 8)
 793                 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 794 }
 795
 796 static void hid_scan_collection(struct hid_parser *parser, unsigned type)
 797 {
 798         struct hid_device *hid = parser->device;
 799         int i;
 800
 801         if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
 802             (type == HID_COLLECTION_PHYSICAL ||
 803              type == HID_COLLECTION_APPLICATION))
 804                 hid->group = HID_GROUP_SENSOR_HUB;
 805
 806         if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
 807             hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
 808             hid->group == HID_GROUP_MULTITOUCH)
 809                 hid->group = HID_GROUP_GENERIC;
 810
 811         if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
 812                 for (i = 0; i < parser->local.usage_index; i++)
 813                         if (parser->local.usage[i] == HID_GD_POINTER)
 814                                 parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
 815
 816         if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
 817                 parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
 818
 819         if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR)
 820                 for (i = 0; i < parser->local.usage_index; i++)
 821                         if (parser->local.usage[i] ==
 822                                         (HID_UP_GOOGLEVENDOR | 0x0001))
 823                                 parser->device->group =
 824                                         HID_GROUP_VIVALDI;
 825 }
 826
 827 static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
 828 {
 829         __u32 data;
 830         int i;
 831
 832         hid_concatenate_last_usage_page(parser);
 833
 834         data = item_udata(item);
 835
 836         switch (item->tag) {
 837         case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 838                 hid_scan_collection(parser, data & 0xff);
 839                 break;
 840         case HID_MAIN_ITEM_TAG_END_COLLECTION:
 841                 break;
 842         case HID_MAIN_ITEM_TAG_INPUT:
 843                 /* ignore constant inputs, they will be ignored by hid-input */
 844                 if (data & HID_MAIN_ITEM_CONSTANT)
 845                         break;
 846                 for (i = 0; i < parser->local.usage_index; i++)
 847                         hid_scan_input_usage(parser, parser->local.usage[i]);
 848                 break;
 849         case HID_MAIN_ITEM_TAG_OUTPUT:
 850                 break;
 851         case HID_MAIN_ITEM_TAG_FEATURE:
 852                 for (i = 0; i < parser->local.usage_index; i++)
 853                         hid_scan_feature_usage(parser, parser->local.usage[i]);
 854                 break;
 855         }
 856
 857         /* Reset the local parser environment */
 858         memset(&parser->local, 0, sizeof(parser->local));
 859
 860         return 0;
 861 }
 862
 863 /*
 864  * Scan a report descriptor before the device is added to the bus.
 865  * Sets device groups and other properties that determine what driver
 866  * to load.
 867  */
 868 static int hid_scan_report(struct hid_device *hid)
 869 {
 870         struct hid_parser *parser;
 871         struct hid_item item;
 872         __u8 *start = hid->dev_rdesc;
 873         __u8 *end = start + hid->dev_rsize;
 874         static int (*dispatch_type[])(struct hid_parser *parser,
 875                                       struct hid_item *item) = {
 876                 hid_scan_main,
 877                 hid_parser_global,
 878                 hid_parser_local,
 879                 hid_parser_reserved
 880         };
 881
 882         parser = vzalloc(sizeof(struct hid_parser));
 883         if (!parser)
 884                 return -ENOMEM;
 885
 886         parser->device = hid;
 887         hid->group = HID_GROUP_GENERIC;
 888
 889         /*
 890          * The parsing is simpler than the one in hid_open_report() as we should
 891          * be robust against hid errors. Those errors will be raised by
 892          * hid_open_report() anyway.
 893          */
 894         while ((start = fetch_item(start, end, &item)) != NULL)
 895                 dispatch_type[item.type](parser, &item);
 896
 897         /*
 898          * Handle special flags set during scanning.
 899          */
 900         if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
 901             (hid->group == HID_GROUP_MULTITOUCH))
 902                 hid->group = HID_GROUP_MULTITOUCH_WIN_8;
 903
 904         /*
 905          * Vendor specific handlings
 906          */
 907         switch (hid->vendor) {
 908         case USB_VENDOR_ID_WACOM:
 909                 hid->group = HID_GROUP_WACOM;
 910                 break;
 911         case USB_VENDOR_ID_SYNAPTICS:
 912                 if (hid->group == HID_GROUP_GENERIC)
 913                         if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
 914                             && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
 915                                 /*
 916                                  * hid-rmi should take care of them,
 917                                  * not hid-generic
 918                                  */
 919                                 hid->group = HID_GROUP_RMI;
 920                 break;
 921         }
 922
 923         kfree(parser->collection_stack);
 924         vfree(parser);
 925         return 0;
 926 }
 927
 928 /**
 929  * hid_parse_report - parse device report
 930  *
 931  * @hid: hid device
 932  * @start: report start
 933  * @size: report size
 934  *
 935  * Allocate the device report as read by the bus driver. This function should
 936  * only be called from parse() in ll drivers.
 937  */
 938 int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
 939 {
 940         hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
 941         if (!hid->dev_rdesc)
 942                 return -ENOMEM;
 943         hid->dev_rsize = size;
 944         return 0;
 945 }
 946 EXPORT_SYMBOL_GPL(hid_parse_report);
 947
 948 static const char * const hid_report_names[] = {
 949         "HID_INPUT_REPORT",
 950         "HID_OUTPUT_REPORT",
 951         "HID_FEATURE_REPORT",
 952 };
 953 /**
 954  * hid_validate_values - validate existing device report's value indexes
 955  *
 956  * @hid: hid device
 957  * @type: which report type to examine
 958  * @id: which report ID to examine (0 for first)
 959  * @field_index: which report field to examine
 960  * @report_counts: expected number of values
 961  *
 962  * Validate the number of values in a given field of a given report, after
 963  * parsing.
 964  */
 965 struct hid_report *hid_validate_values(struct hid_device *hid,
 966                                        enum hid_report_type type, unsigned int id,
 967                                        unsigned int field_index,
 968                                        unsigned int report_counts)
 969 {
 970         struct hid_report *report;
 971
 972         if (type > HID_FEATURE_REPORT) {
 973                 hid_err(hid, "invalid HID report type %u\n", type);
 974                 return NULL;
 975         }
 976
 977         if (id >= HID_MAX_IDS) {
 978                 hid_err(hid, "invalid HID report id %u\n", id);
 979                 return NULL;
 980         }
 981
 982         /*
 983          * Explicitly not using hid_get_report() here since it depends on
 984          * ->numbered being checked, which may not always be the case when
 985          * drivers go to access report values.
 986          */
 987         if (id == 0) {
 988                 /*
 989                  * Validating on id 0 means we should examine the first
 990                  * report in the list.
 991                  */
 992                 report = list_first_entry_or_null(
 993                                 &hid->report_enum[type].report_list,
 994                                 struct hid_report, list);
 995         } else {
 996                 report = hid->report_enum[type].report_id_hash[id];
 997         }
 998         if (!report) {
 999                 hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
1000                 return NULL;
1001         }
1002         if (report->maxfield <= field_index) {
1003                 hid_err(hid, "not enough fields in %s %u\n",
1004                         hid_report_names[type], id);
1005                 return NULL;
1006         }
1007         if (report->field[field_index]->report_count < report_counts) {
1008                 hid_err(hid, "not enough values in %s %u field %u\n",
1009                         hid_report_names[type], id, field_index);
1010                 return NULL;
1011         }
1012         return report;
1013 }
1014 EXPORT_SYMBOL_GPL(hid_validate_values);
1015
1016 static int hid_calculate_multiplier(struct hid_device *hid,
1017                                      struct hid_field *multiplier)
1018 {
1019         int m;
1020         __s32 v = *multiplier->value;
1021         __s32 lmin = multiplier->logical_minimum;
1022         __s32 lmax = multiplier->logical_maximum;
1023         __s32 pmin = multiplier->physical_minimum;
1024         __s32 pmax = multiplier->physical_maximum;
1025
1026         /*
1027          * "Because OS implementations will generally divide the control's
1028          * reported count by the Effective Resolution Multiplier, designers
1029          * should take care not to establish a potential Effective
1030          * Resolution Multiplier of zero."
1031          * HID Usage Table, v1.12, Section 4.3.1, p31
1032          */
1033         if (lmax - lmin == 0)
1034                 return 1;
1035         /*
1036          * Handling the unit exponent is left as an exercise to whoever
1037          * finds a device where that exponent is not 0.
1038          */
1039         m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
1040         if (unlikely(multiplier->unit_exponent != 0)) {
1041                 hid_warn(hid,
1042                          "unsupported Resolution Multiplier unit exponent %d\n",
1043                          multiplier->unit_exponent);
1044         }
1045
1046         /* There are no devices with an effective multiplier > 255 */
1047         if (unlikely(m == 0 || m > 255 || m < -255)) {
1048                 hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
1049                 m = 1;
1050         }
1051
1052         return m;
1053 }
1054
1055 static void hid_apply_multiplier_to_field(struct hid_device *hid,
1056                                           struct hid_field *field,
1057                                           struct hid_collection *multiplier_collection,
1058                                           int effective_multiplier)
1059 {
1060         struct hid_collection *collection;
1061         struct hid_usage *usage;
1062         int i;
1063
1064         /*
1065          * If multiplier_collection is NULL, the multiplier applies
1066          * to all fields in the report.
1067          * Otherwise, it is the Logical Collection the multiplier applies to
1068          * but our field may be in a subcollection of that collection.
1069          */
1070         for (i = 0; i < field->maxusage; i++) {
1071                 usage = &field->usage[i];
1072
1073                 collection = &hid->collection[usage->collection_index];
1074                 while (collection->parent_idx != -1 &&
1075                        collection != multiplier_collection)
1076                         collection = &hid->collection[collection->parent_idx];
1077
1078                 if (collection->parent_idx != -1 ||
1079                     multiplier_collection == NULL)
1080                         usage->resolution_multiplier = effective_multiplier;
1081
1082         }
1083 }
1084
1085 static void hid_apply_multiplier(struct hid_device *hid,
1086                                  struct hid_field *multiplier)
1087 {
1088         struct hid_report_enum *rep_enum;
1089         struct hid_report *rep;
1090         struct hid_field *field;
1091         struct hid_collection *multiplier_collection;
1092         int effective_multiplier;
1093         int i;
1094
1095         /*
1096          * "The Resolution Multiplier control must be contained in the same
1097          * Logical Collection as the control(s) to which it is to be applied.
1098          * If no Resolution Multiplier is defined, then the Resolution
1099          * Multiplier defaults to 1.  If more than one control exists in a
1100          * Logical Collection, the Resolution Multiplier is associated with
1101          * all controls in the collection. If no Logical Collection is
1102          * defined, the Resolution Multiplier is associated with all
1103          * controls in the report."
1104          * HID Usage Table, v1.12, Section 4.3.1, p30
1105          *
1106          * Thus, search from the current collection upwards until we find a
1107          * logical collection. Then search all fields for that same parent
1108          * collection. Those are the fields the multiplier applies to.
1109          *
1110          * If we have more than one multiplier, it will overwrite the
1111          * applicable fields later.
1112          */
1113         multiplier_collection = &hid->collection[multiplier->usage->collection_index];
1114         while (multiplier_collection->parent_idx != -1 &&
1115                multiplier_collection->type != HID_COLLECTION_LOGICAL)
1116                 multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
1117
1118         effective_multiplier = hid_calculate_multiplier(hid, multiplier);
1119
1120         rep_enum = &hid->report_enum[HID_INPUT_REPORT];
1121         list_for_each_entry(rep, &rep_enum->report_list, list) {
1122                 for (i = 0; i < rep->maxfield; i++) {
1123                         field = rep->field[i];
1124                         hid_apply_multiplier_to_field(hid, field,
1125                                                       multiplier_collection,
1126                                                       effective_multiplier);
1127                 }
1128         }
1129 }
1130
1131 /*
1132  * hid_setup_resolution_multiplier - set up all resolution multipliers
1133  *
1134  * @device: hid device
1135  *
1136  * Search for all Resolution Multiplier Feature Reports and apply their
1137  * value to all matching Input items. This only updates the internal struct
1138  * fields.
1139  *
1140  * The Resolution Multiplier is applied by the hardware. If the multiplier
1141  * is anything other than 1, the hardware will send pre-multiplied events
1142  * so that the same physical interaction generates an accumulated
1143  *      accumulated_value = value * * multiplier
1144  * This may be achieved by sending
1145  * - "value * multiplier" for each event, or
1146  * - "value" but "multiplier" times as frequently, or
1147  * - a combination of the above
1148  * The only guarantee is that the same physical interaction always generates
1149  * an accumulated 'value * multiplier'.
1150  *
1151  * This function must be called before any event processing and after
1152  * any SetRequest to the Resolution Multiplier.
1153  */
1154 void hid_setup_resolution_multiplier(struct hid_device *hid)
1155 {
1156         struct hid_report_enum *rep_enum;
1157         struct hid_report *rep;
1158         struct hid_usage *usage;
1159         int i, j;
1160
1161         rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
1162         list_for_each_entry(rep, &rep_enum->report_list, list) {
1163                 for (i = 0; i < rep->maxfield; i++) {
1164                         /* Ignore if report count is out of bounds. */
1165                         if (rep->field[i]->report_count < 1)
1166                                 continue;
1167
1168                         for (j = 0; j < rep->field[i]->maxusage; j++) {
1169                                 usage = &rep->field[i]->usage[j];
1170                                 if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
1171                                         hid_apply_multiplier(hid,
1172                                                              rep->field[i]);
1173                         }
1174                 }
1175         }
1176 }
1177 EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
1178
1179 /**
1180  * hid_open_report - open a driver-specific device report
1181  *
1182  * @device: hid device
1183  *
1184  * Parse a report description into a hid_device structure. Reports are
1185  * enumerated, fields are attached to these reports.
1186  * 0 returned on success, otherwise nonzero error value.
1187  *
1188  * This function (or the equivalent hid_parse() macro) should only be
1189  * called from probe() in drivers, before starting the device.
1190  */
1191 int hid_open_report(struct hid_device *device)
1192 {
1193         struct hid_parser *parser;
1194         struct hid_item item;
1195         unsigned int size;
1196         __u8 *start;
1197         __u8 *buf;
1198         __u8 *end;
1199         __u8 *next;
1200         int ret;
1201         int i;
1202         static int (*dispatch_type[])(struct hid_parser *parser,
1203                                       struct hid_item *item) = {
1204                 hid_parser_main,
1205                 hid_parser_global,
1206                 hid_parser_local,
1207                 hid_parser_reserved
1208         };
1209
1210         if (WARN_ON(device->status & HID_STAT_PARSED))
1211                 return -EBUSY;
1212
1213         start = device->dev_rdesc;
1214         if (WARN_ON(!start))
1215                 return -ENODEV;
1216         size = device->dev_rsize;
1217
1218         /* call_hid_bpf_rdesc_fixup() ensures we work on a copy of rdesc */
1219         buf = call_hid_bpf_rdesc_fixup(device, start, &size);
1220         if (buf == NULL)
1221                 return -ENOMEM;
1222
1223         if (device->driver->report_fixup)
1224                 start = device->driver->report_fixup(device, buf, &size);
1225         else
1226                 start = buf;
1227
1228         start = kmemdup(start, size, GFP_KERNEL);
1229         kfree(buf);
1230         if (start == NULL)
1231                 return -ENOMEM;
1232
1233         device->rdesc = start;
1234         device->rsize = size;
1235
1236         parser = vzalloc(sizeof(struct hid_parser));
1237         if (!parser) {
1238                 ret = -ENOMEM;
1239                 goto alloc_err;
1240         }
1241
1242         parser->device = device;
1243
1244         end = start + size;
1245
1246         device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
1247                                      sizeof(struct hid_collection), GFP_KERNEL);
1248         if (!device->collection) {
1249                 ret = -ENOMEM;
1250                 goto err;
1251         }
1252         device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
1253         for (i = 0; i < HID_DEFAULT_NUM_COLLECTIONS; i++)
1254                 device->collection[i].parent_idx = -1;
1255
1256         ret = -EINVAL;
1257         while ((next = fetch_item(start, end, &item)) != NULL) {
1258                 start = next;
1259
1260                 if (item.format != HID_ITEM_FORMAT_SHORT) {
1261                         hid_err(device, "unexpected long global item\n");
1262                         goto err;
1263                 }
1264
1265                 if (dispatch_type[item.type](parser, &item)) {
1266                         hid_err(device, "item %u %u %u %u parsing failed\n",
1267                                 item.format, (unsigned)item.size,
1268                                 (unsigned)item.type, (unsigned)item.tag);
1269                         goto err;
1270                 }
1271
1272                 if (start == end) {
1273                         if (parser->collection_stack_ptr) {
1274                                 hid_err(device, "unbalanced collection at end of report description\n");
1275                                 goto err;
1276                         }
1277                         if (parser->local.delimiter_depth) {
1278                                 hid_err(device, "unbalanced delimiter at end of report description\n");
1279                                 goto err;
1280                         }
1281
1282                         /*
1283                          * fetch initial values in case the device's
1284                          * default multiplier isn't the recommended 1
1285                          */
1286                         hid_setup_resolution_multiplier(device);
1287
1288                         kfree(parser->collection_stack);
1289                         vfree(parser);
1290                         device->status |= HID_STAT_PARSED;
1291
1292                         return 0;
1293                 }
1294         }
1295
1296         hid_err(device, "item fetching failed at offset %u/%u\n",
1297                 size - (unsigned int)(end - start), size);
1298 err:
1299         kfree(parser->collection_stack);
1300 alloc_err:
1301         vfree(parser);
1302         hid_close_report(device);
1303         return ret;
1304 }
1305 EXPORT_SYMBOL_GPL(hid_open_report);
1306
1307 /*
1308  * Convert a signed n-bit integer to signed 32-bit integer. Common
1309  * cases are done through the compiler, the screwed things has to be
1310  * done by hand.
1311  */
1312
1313 static s32 snto32(__u32 value, unsigned n)
1314 {
1315         if (!value || !n)
1316                 return 0;
1317
1318         if (n > 32)
1319                 n = 32;
1320
1321         switch (n) {
1322         case 8:  return ((__s8)value);
1323         case 16: return ((__s16)value);
1324         case 32: return ((__s32)value);
1325         }
1326         return value & (1 << (n - 1)) ? value | (~0U << n) : value;
1327 }
1328
1329 s32 hid_snto32(__u32 value, unsigned n)
1330 {
1331         return snto32(value, n);
1332 }
1333 EXPORT_SYMBOL_GPL(hid_snto32);
1334
1335 /*
1336  * Convert a signed 32-bit integer to a signed n-bit integer.
1337  */
1338
1339 static u32 s32ton(__s32 value, unsigned n)
1340 {
1341         s32 a = value >> (n - 1);
1342         if (a && a != -1)
1343                 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
1344         return value & ((1 << n) - 1);
1345 }
1346
1347 /*
1348  * Extract/implement a data field from/to a little endian report (bit array).
1349  *
1350  * Code sort-of follows HID spec:
1351  *     http://www.usb.org/developers/hidpage/HID1_11.pdf
1352  *
1353  * While the USB HID spec allows unlimited length bit fields in "report
1354  * descriptors", most devices never use more than 16 bits.
1355  * One model of UPS is claimed to report "LINEV" as a 32-bit field.
1356  * Search linux-kernel and linux-usb-devel archives for "hid-core extract".
1357  */
1358
1359 static u32 __extract(u8 *report, unsigned offset, int n)
1360 {
1361         unsigned int idx = offset / 8;
1362         unsigned int bit_nr = 0;
1363         unsigned int bit_shift = offset % 8;
1364         int bits_to_copy = 8 - bit_shift;
1365         u32 value = 0;
1366         u32 mask = n < 32 ? (1U << n) - 1 : ~0U;
1367
1368         while (n > 0) {
1369                 value |= ((u32)report[idx] >> bit_shift) << bit_nr;
1370                 n -= bits_to_copy;
1371                 bit_nr += bits_to_copy;
1372                 bits_to_copy = 8;
1373                 bit_shift = 0;
1374                 idx++;
1375         }
1376
1377         return value & mask;
1378 }
1379
1380 u32 hid_field_extract(const struct hid_device *hid, u8 *report,
1381                         unsigned offset, unsigned n)
1382 {
1383         if (n > 32) {
1384                 hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
1385                               __func__, n, current->comm);
1386                 n = 32;
1387         }
1388
1389         return __extract(report, offset, n);
1390 }
1391 EXPORT_SYMBOL_GPL(hid_field_extract);
1392
1393 /*
1394  * "implement" : set bits in a little endian bit stream.
1395  * Same concepts as "extract" (see comments above).
1396  * The data mangled in the bit stream remains in little endian
1397  * order the whole time. It make more sense to talk about
1398  * endianness of register values by considering a register
1399  * a "cached" copy of the little endian bit stream.
1400  */
1401
1402 static void __implement(u8 *report, unsigned offset, int n, u32 value)
1403 {
1404         unsigned int idx = offset / 8;
1405         unsigned int bit_shift = offset % 8;
1406         int bits_to_set = 8 - bit_shift;
1407
1408         while (n - bits_to_set >= 0) {
1409                 report[idx] &= ~(0xff << bit_shift);
1410                 report[idx] |= value << bit_shift;
1411                 value >>= bits_to_set;
1412                 n -= bits_to_set;
1413                 bits_to_set = 8;
1414                 bit_shift = 0;
1415                 idx++;
1416         }
1417
1418         /* last nibble */
1419         if (n) {
1420                 u8 bit_mask = ((1U << n) - 1);
1421                 report[idx] &= ~(bit_mask << bit_shift);
1422                 report[idx] |= value << bit_shift;
1423         }
1424 }
1425
1426 static void implement(const struct hid_device *hid, u8 *report,
1427                       unsigned offset, unsigned n, u32 value)
1428 {
1429         if (unlikely(n > 32)) {
1430                 hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
1431                          __func__, n, current->comm);
1432                 n = 32;
1433         } else if (n < 32) {
1434                 u32 m = (1U << n) - 1;
1435
1436                 if (unlikely(value > m)) {
1437                         hid_warn(hid,
1438                                  "%s() called with too large value %d (n: %d)! (%s)\n",
1439                                  __func__, value, n, current->comm);
1440                         WARN_ON(1);
1441                         value &= m;
1442                 }
1443         }
1444
1445         __implement(report, offset, n, value);
1446 }
1447
1448 /*
1449  * Search an array for a value.
1450  */
1451
1452 static int search(__s32 *array, __s32 value, unsigned n)
1453 {
1454         while (n--) {
1455                 if (*array++ == value)
1456                         return 0;
1457         }
1458         return -1;
1459 }
1460
1461 /**
1462  * hid_match_report - check if driver's raw_event should be called
1463  *
1464  * @hid: hid device
1465  * @report: hid report to match against
1466  *
1467  * compare hid->driver->report_table->report_type to report->type
1468  */
1469 static int hid_match_report(struct hid_device *hid, struct hid_report *report)
1470 {
1471         const struct hid_report_id *id = hid->driver->report_table;
1472
1473         if (!id) /* NULL means all */
1474                 return 1;
1475
1476         for (; id->report_type != HID_TERMINATOR; id++)
1477                 if (id->report_type == HID_ANY_ID ||
1478                                 id->report_type == report->type)
1479                         return 1;
1480         return 0;
1481 }
1482
1483 /**
1484  * hid_match_usage - check if driver's event should be called
1485  *
1486  * @hid: hid device
1487  * @usage: usage to match against
1488  *
1489  * compare hid->driver->usage_table->usage_{type,code} to
1490  * usage->usage_{type,code}
1491  */
1492 static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage)
1493 {
1494         const struct hid_usage_id *id = hid->driver->usage_table;
1495
1496         if (!id) /* NULL means all */
1497                 return 1;
1498
1499         for (; id->usage_type != HID_ANY_ID - 1; id++)
1500                 if ((id->usage_hid == HID_ANY_ID ||
1501                                 id->usage_hid == usage->hid) &&
1502                                 (id->usage_type == HID_ANY_ID ||
1503                                 id->usage_type == usage->type) &&
1504                                 (id->usage_code == HID_ANY_ID ||
1505                                  id->usage_code == usage->code))
1506                         return 1;
1507         return 0;
1508 }
1509
1510 static void hid_process_event(struct hid_device *hid, struct hid_field *field,
1511                 struct hid_usage *usage, __s32 value, int interrupt)
1512 {
1513         struct hid_driver *hdrv = hid->driver;
1514         int ret;
1515
1516         if (!list_empty(&hid->debug_list))
1517                 hid_dump_input(hid, usage, value);
1518
1519         if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
1520                 ret = hdrv->event(hid, field, usage, value);
1521                 if (ret != 0) {
1522                         if (ret < 0)
1523                                 hid_err(hid, "%s's event failed with %d\n",
1524                                                 hdrv->name, ret);
1525                         return;
1526                 }
1527         }
1528
1529         if (hid->claimed & HID_CLAIMED_INPUT)
1530                 hidinput_hid_event(hid, field, usage, value);
1531         if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
1532                 hid->hiddev_hid_event(hid, field, usage, value);
1533 }
1534
1535 /*
1536  * Checks if the given value is valid within this field
1537  */
1538 static inline int hid_array_value_is_valid(struct hid_field *field,
1539                                            __s32 value)
1540 {
1541         __s32 min = field->logical_minimum;
1542
1543         /*
1544          * Value needs to be between logical min and max, and
1545          * (value - min) is used as an index in the usage array.
1546          * This array is of size field->maxusage
1547          */
1548         return value >= min &&
1549                value <= field->logical_maximum &&
1550                value - min < field->maxusage;
1551 }
1552
1553 /*
1554  * Fetch the field from the data. The field content is stored for next
1555  * report processing (we do differential reporting to the layer).
1556  */
1557 static void hid_input_fetch_field(struct hid_device *hid,
1558                                   struct hid_field *field,
1559                                   __u8 *data)
1560 {
1561         unsigned n;
1562         unsigned count = field->report_count;
1563         unsigned offset = field->report_offset;
1564         unsigned size = field->report_size;
1565         __s32 min = field->logical_minimum;
1566         __s32 *value;
1567
1568         value = field->new_value;
1569         memset(value, 0, count * sizeof(__s32));
1570         field->ignored = false;
1571
1572         for (n = 0; n < count; n++) {
1573
1574                 value[n] = min < 0 ?
1575                         snto32(hid_field_extract(hid, data, offset + n * size,
1576                                size), size) :
1577                         hid_field_extract(hid, data, offset + n * size, size);
1578
1579                 /* Ignore report if ErrorRollOver */
1580                 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&
1581                     hid_array_value_is_valid(field, value[n]) &&
1582                     field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) {
1583                         field->ignored = true;
1584                         return;
1585                 }
1586         }
1587 }
1588
1589 /*
1590  * Process a received variable field.
1591  */
1592
1593 static void hid_input_var_field(struct hid_device *hid,
1594                                 struct hid_field *field,
1595                                 int interrupt)
1596 {
1597         unsigned int count = field->report_count;
1598         __s32 *value = field->new_value;
1599         unsigned int n;
1600
1601         for (n = 0; n < count; n++)
1602                 hid_process_event(hid,
1603                                   field,
1604                                   &field->usage[n],
1605                                   value[n],
1606                                   interrupt);
1607
1608         memcpy(field->value, value, count * sizeof(__s32));
1609 }
1610
1611 /*
1612  * Process a received array field. The field content is stored for
1613  * next report processing (we do differential reporting to the layer).
1614  */
1615
1616 static void hid_input_array_field(struct hid_device *hid,
1617                                   struct hid_field *field,
1618                                   int interrupt)
1619 {
1620         unsigned int n;
1621         unsigned int count = field->report_count;
1622         __s32 min = field->logical_minimum;
1623         __s32 *value;
1624
1625         value = field->new_value;
1626
1627         /* ErrorRollOver */
1628         if (field->ignored)
1629                 return;
1630
1631         for (n = 0; n < count; n++) {
1632                 if (hid_array_value_is_valid(field, field->value[n]) &&
1633                     search(value, field->value[n], count))
1634                         hid_process_event(hid,
1635                                           field,
1636                                           &field->usage[field->value[n] - min],
1637                                           0,
1638                                           interrupt);
1639
1640                 if (hid_array_value_is_valid(field, value[n]) &&
1641                     search(field->value, value[n], count))
1642                         hid_process_event(hid,
1643                                           field,
1644                                           &field->usage[value[n] - min],
1645                                           1,
1646                                           interrupt);
1647         }
1648
1649         memcpy(field->value, value, count * sizeof(__s32));
1650 }
1651
1652 /*
1653  * Analyse a received report, and fetch the data from it. The field
1654  * content is stored for next report processing (we do differential
1655  * reporting to the layer).
1656  */
1657 static void hid_process_report(struct hid_device *hid,
1658                                struct hid_report *report,
1659                                __u8 *data,
1660                                int interrupt)
1661 {
1662         unsigned int a;
1663         struct hid_field_entry *entry;
1664         struct hid_field *field;
1665
1666         /* first retrieve all incoming values in data */
1667         for (a = 0; a < report->maxfield; a++)
1668                 hid_input_fetch_field(hid, report->field[a], data);
1669
1670         if (!list_empty(&report->field_entry_list)) {
1671                 /* INPUT_REPORT, we have a priority list of fields */
1672                 list_for_each_entry(entry,
1673                                     &report->field_entry_list,
1674                                     list) {
1675                         field = entry->field;
1676
1677                         if (field->flags & HID_MAIN_ITEM_VARIABLE)
1678                                 hid_process_event(hid,
1679                                                   field,
1680                                                   &field->usage[entry->index],
1681                                                   field->new_value[entry->index],
1682                                                   interrupt);
1683                         else
1684                                 hid_input_array_field(hid, field, interrupt);
1685                 }
1686
1687                 /* we need to do the memcpy at the end for var items */
1688                 for (a = 0; a < report->maxfield; a++) {
1689                         field = report->field[a];
1690
1691                         if (field->flags & HID_MAIN_ITEM_VARIABLE)
1692                                 memcpy(field->value, field->new_value,
1693                                        field->report_count * sizeof(__s32));
1694                 }
1695         } else {
1696                 /* FEATURE_REPORT, regular processing */
1697                 for (a = 0; a < report->maxfield; a++) {
1698                         field = report->field[a];
1699
1700                         if (field->flags & HID_MAIN_ITEM_VARIABLE)
1701                                 hid_input_var_field(hid, field, interrupt);
1702                         else
1703                                 hid_input_array_field(hid, field, interrupt);
1704                 }
1705         }
1706 }
1707
1708 /*
1709  * Insert a given usage_index in a field in the list
1710  * of processed usages in the report.
1711  *
1712  * The elements of lower priority score are processed
1713  * first.
1714  */
1715 static void __hid_insert_field_entry(struct hid_device *hid,
1716                                      struct hid_report *report,
1717                                      struct hid_field_entry *entry,
1718                                      struct hid_field *field,
1719                                      unsigned int usage_index)
1720 {
1721         struct hid_field_entry *next;
1722
1723         entry->field = field;
1724         entry->index = usage_index;
1725         entry->priority = field->usages_priorities[usage_index];
1726
1727         /* insert the element at the correct position */
1728         list_for_each_entry(next,
1729                             &report->field_entry_list,
1730                             list) {
1731                 /*
1732                  * the priority of our element is strictly higher
1733                  * than the next one, insert it before
1734                  */
1735                 if (entry->priority > next->priority) {
1736                         list_add_tail(&entry->list, &next->list);
1737                         return;
1738                 }
1739         }
1740
1741         /* lowest priority score: insert at the end */
1742         list_add_tail(&entry->list, &report->field_entry_list);
1743 }
1744
1745 static void hid_report_process_ordering(struct hid_device *hid,
1746                                         struct hid_report *report)
1747 {
1748         struct hid_field *field;
1749         struct hid_field_entry *entries;
1750         unsigned int a, u, usages;
1751         unsigned int count = 0;
1752
1753         /* count the number of individual fields in the report */
1754         for (a = 0; a < report->maxfield; a++) {
1755                 field = report->field[a];
1756
1757                 if (field->flags & HID_MAIN_ITEM_VARIABLE)
1758                         count += field->report_count;
1759                 else
1760                         count++;
1761         }
1762
1763         /* allocate the memory to process the fields */
1764         entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
1765         if (!entries)
1766                 return;
1767
1768         report->field_entries = entries;
1769
1770         /*
1771          * walk through all fields in the report and
1772          * store them by priority order in report->field_entry_list
1773          *
1774          * - Var elements are individualized (field + usage_index)
1775          * - Arrays are taken as one, we can not chose an order for them
1776          */
1777         usages = 0;
1778         for (a = 0; a < report->maxfield; a++) {
1779                 field = report->field[a];
1780
1781                 if (field->flags & HID_MAIN_ITEM_VARIABLE) {
1782                         for (u = 0; u < field->report_count; u++) {
1783                                 __hid_insert_field_entry(hid, report,
1784                                                          &entries[usages],
1785                                                          field, u);
1786                                 usages++;
1787                         }
1788                 } else {
1789                         __hid_insert_field_entry(hid, report, &entries[usages],
1790                                                  field, 0);
1791                         usages++;
1792                 }
1793         }
1794 }
1795
1796 static void hid_process_ordering(struct hid_device *hid)
1797 {
1798         struct hid_report *report;
1799         struct hid_report_enum *report_enum = &hid->report_enum[HID_INPUT_REPORT];
1800
1801         list_for_each_entry(report, &report_enum->report_list, list)
1802                 hid_report_process_ordering(hid, report);
1803 }
1804
1805 /*
1806  * Output the field into the report.
1807  */
1808
1809 static void hid_output_field(const struct hid_device *hid,
1810                              struct hid_field *field, __u8 *data)
1811 {
1812         unsigned count = field->report_count;
1813         unsigned offset = field->report_offset;
1814         unsigned size = field->report_size;
1815         unsigned n;
1816
1817         for (n = 0; n < count; n++) {
1818                 if (field->logical_minimum < 0) /* signed values */
1819                         implement(hid, data, offset + n * size, size,
1820                                   s32ton(field->value[n], size));
1821                 else                            /* unsigned values */
1822                         implement(hid, data, offset + n * size, size,
1823                                   field->value[n]);
1824         }
1825 }
1826
1827 /*
1828  * Compute the size of a report.
1829  */
1830 static size_t hid_compute_report_size(struct hid_report *report)
1831 {
1832         if (report->size)
1833                 return ((report->size - 1) >> 3) + 1;
1834
1835         return 0;
1836 }
1837
1838 /*
1839  * Create a report. 'data' has to be allocated using
1840  * hid_alloc_report_buf() so that it has proper size.
1841  */
1842
1843 void hid_output_report(struct hid_report *report, __u8 *data)
1844 {
1845         unsigned n;
1846
1847         if (report->id > 0)
1848                 *data++ = report->id;
1849
1850         memset(data, 0, hid_compute_report_size(report));
1851         for (n = 0; n < report->maxfield; n++)
1852                 hid_output_field(report->device, report->field[n], data);
1853 }
1854 EXPORT_SYMBOL_GPL(hid_output_report);
1855
1856 /*
1857  * Allocator for buffer that is going to be passed to hid_output_report()
1858  */
1859 u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
1860 {
1861         /*
1862          * 7 extra bytes are necessary to achieve proper functionality
1863          * of implement() working on 8 byte chunks
1864          */
1865
1866         u32 len = hid_report_len(report) + 7;
1867
1868         return kmalloc(len, flags);
1869 }
1870 EXPORT_SYMBOL_GPL(hid_alloc_report_buf);
1871
1872 /*
1873  * Set a field value. The report this field belongs to has to be
1874  * created and transferred to the device, to set this value in the
1875  * device.
1876  */
1877
1878 int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
1879 {
1880         unsigned size;
1881
1882         if (!field)
1883                 return -1;
1884
1885         size = field->report_size;
1886
1887         hid_dump_input(field->report->device, field->usage + offset, value);
1888
1889         if (offset >= field->report_count) {
1890                 hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n",
1891                                 offset, field->report_count);
1892                 return -1;
1893         }
1894         if (field->logical_minimum < 0) {
1895                 if (value != snto32(s32ton(value, size), size)) {
1896                         hid_err(field->report->device, "value %d is out of range\n", value);
1897                         return -1;
1898                 }
1899         }
1900         field->value[offset] = value;
1901         return 0;
1902 }
1903 EXPORT_SYMBOL_GPL(hid_set_field);
1904
1905 static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
1906                 const u8 *data)
1907 {
1908         struct hid_report *report;
1909         unsigned int n = 0;     /* Normally report number is 0 */
1910
1911         /* Device uses numbered reports, data[0] is report number */
1912         if (report_enum->numbered)
1913                 n = *data;
1914
1915         report = report_enum->report_id_hash[n];
1916         if (report == NULL)
1917                 dbg_hid("undefined report_id %u received\n", n);
1918
1919         return report;
1920 }
1921
1922 /*
1923  * Implement a generic .request() callback, using .raw_request()
1924  * DO NOT USE in hid drivers directly, but through hid_hw_request instead.
1925  */
1926 int __hid_request(struct hid_device *hid, struct hid_report *report,
1927                 enum hid_class_request reqtype)
1928 {
1929         char *buf;
1930         int ret;
1931         u32 len;
1932
1933         buf = hid_alloc_report_buf(report, GFP_KERNEL);
1934         if (!buf)
1935                 return -ENOMEM;
1936
1937         len = hid_report_len(report);
1938
1939         if (reqtype == HID_REQ_SET_REPORT)
1940                 hid_output_report(report, buf);
1941
1942         ret = hid->ll_driver->raw_request(hid, report->id, buf, len,
1943                                           report->type, reqtype);
1944         if (ret < 0) {
1945                 dbg_hid("unable to complete request: %d\n", ret);
1946                 goto out;
1947         }
1948
1949         if (reqtype == HID_REQ_GET_REPORT)
1950                 hid_input_report(hid, report->type, buf, ret, 0);
1951
1952         ret = 0;
1953
1954 out:
1955         kfree(buf);
1956         return ret;
1957 }
1958 EXPORT_SYMBOL_GPL(__hid_request);
1959
1960 int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
1961                          int interrupt)
1962 {
1963         struct hid_report_enum *report_enum = hid->report_enum + type;
1964         struct hid_report *report;
1965         struct hid_driver *hdrv;
1966         u32 rsize, csize = size;
1967         u8 *cdata = data;
1968         int ret = 0;
1969
1970         report = hid_get_report(report_enum, data);
1971         if (!report)
1972                 goto out;
1973
1974         if (report_enum->numbered) {
1975                 cdata++;
1976                 csize--;
1977         }
1978
1979         rsize = hid_compute_report_size(report);
1980
1981         if (report_enum->numbered && rsize >= HID_MAX_BUFFER_SIZE)
1982                 rsize = HID_MAX_BUFFER_SIZE - 1;
1983         else if (rsize > HID_MAX_BUFFER_SIZE)
1984                 rsize = HID_MAX_BUFFER_SIZE;
1985
1986         if (csize < rsize) {
1987                 dbg_hid("report %d is too short, (%d < %d)\n", report->id,
1988                                 csize, rsize);
1989                 memset(cdata + csize, 0, rsize - csize);
1990         }
1991
1992         if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
1993                 hid->hiddev_report_event(hid, report);
1994         if (hid->claimed & HID_CLAIMED_HIDRAW) {
1995                 ret = hidraw_report_event(hid, data, size);
1996                 if (ret)
1997                         goto out;
1998         }
1999
2000         if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
2001                 hid_process_report(hid, report, cdata, interrupt);
2002                 hdrv = hid->driver;
2003                 if (hdrv && hdrv->report)
2004                         hdrv->report(hid, report);
2005         }
2006
2007         if (hid->claimed & HID_CLAIMED_INPUT)
2008                 hidinput_report_event(hid, report);
2009 out:
2010         return ret;
2011 }
2012 EXPORT_SYMBOL_GPL(hid_report_raw_event);
2013
2014 /**
2015  * hid_input_report - report data from lower layer (usb, bt...)
2016  *
2017  * @hid: hid device
2018  * @type: HID report type (HID_*_REPORT)
2019  * @data: report contents
2020  * @size: size of data parameter
2021  * @interrupt: distinguish between interrupt and control transfers
2022  *
2023  * This is data entry for lower layers.
2024  */
2025 int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
2026                      int interrupt)
2027 {
2028         struct hid_report_enum *report_enum;
2029         struct hid_driver *hdrv;
2030         struct hid_report *report;
2031         int ret = 0;
2032
2033         if (!hid)
2034                 return -ENODEV;
2035
2036         if (down_trylock(&hid->driver_input_lock))
2037                 return -EBUSY;
2038
2039         if (!hid->driver) {
2040                 ret = -ENODEV;
2041                 goto unlock;
2042         }
2043         report_enum = hid->report_enum + type;
2044         hdrv = hid->driver;
2045
2046         data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt);
2047         if (IS_ERR(data)) {
2048                 ret = PTR_ERR(data);
2049                 goto unlock;
2050         }
2051
2052         if (!size) {
2053                 dbg_hid("empty report\n");
2054                 ret = -1;
2055                 goto unlock;
2056         }
2057
2058         /* Avoid unnecessary overhead if debugfs is disabled */
2059         if (!list_empty(&hid->debug_list))
2060                 hid_dump_report(hid, type, data, size);
2061
2062         report = hid_get_report(report_enum, data);
2063
2064         if (!report) {
2065                 ret = -1;
2066                 goto unlock;
2067         }
2068
2069         if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
2070                 ret = hdrv->raw_event(hid, report, data, size);
2071                 if (ret < 0)
2072                         goto unlock;
2073         }
2074
2075         ret = hid_report_raw_event(hid, type, data, size, interrupt);
2076
2077 unlock:
2078         up(&hid->driver_input_lock);
2079         return ret;
2080 }
2081 EXPORT_SYMBOL_GPL(hid_input_report);
2082
2083 bool hid_match_one_id(const struct hid_device *hdev,
2084                       const struct hid_device_id *id)
2085 {
2086         return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
2087                 (id->group == HID_GROUP_ANY || id->group == hdev->group) &&
2088                 (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
2089                 (id->product == HID_ANY_ID || id->product == hdev->product);
2090 }
2091
2092 const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
2093                 const struct hid_device_id *id)
2094 {
2095         for (; id->bus; id++)
2096                 if (hid_match_one_id(hdev, id))
2097                         return id;
2098
2099         return NULL;
2100 }
2101 EXPORT_SYMBOL_GPL(hid_match_id);
2102
2103 static const struct hid_device_id hid_hiddev_list[] = {
2104         { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
2105         { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
2106         { }
2107 };
2108
2109 static bool hid_hiddev(struct hid_device *hdev)
2110 {
2111         return !!hid_match_id(hdev, hid_hiddev_list);
2112 }
2113
2114
2115 static ssize_t
2116 read_report_descriptor(struct file *filp, struct kobject *kobj,
2117                 struct bin_attribute *attr,
2118                 char *buf, loff_t off, size_t count)
2119 {
2120         struct device *dev = kobj_to_dev(kobj);
2121         struct hid_device *hdev = to_hid_device(dev);
2122
2123         if (off >= hdev->rsize)
2124                 return 0;
2125
2126         if (off + count > hdev->rsize)
2127                 count = hdev->rsize - off;
2128
2129         memcpy(buf, hdev->rdesc + off, count);
2130
2131         return count;
2132 }
2133
2134 static ssize_t
2135 show_country(struct device *dev, struct device_attribute *attr,
2136                 char *buf)
2137 {
2138         struct hid_device *hdev = to_hid_device(dev);
2139
2140         return sprintf(buf, "%02x\n", hdev->country & 0xff);
2141 }
2142
2143 static struct bin_attribute dev_bin_attr_report_desc = {
2144         .attr = { .name = "report_descriptor", .mode = 0444 },
2145         .read = read_report_descriptor,
2146         .size = HID_MAX_DESCRIPTOR_SIZE,
2147 };
2148
2149 static const struct device_attribute dev_attr_country = {
2150         .attr = { .name = "country", .mode = 0444 },
2151         .show = show_country,
2152 };
2153
2154 int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
2155 {
2156         static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
2157                 "Joystick", "Gamepad", "Keyboard", "Keypad",
2158                 "Multi-Axis Controller"
2159         };
2160         const char *type, *bus;
2161         char buf[64] = "";
2162         unsigned int i;
2163         int len;
2164         int ret;
2165
2166         ret = hid_bpf_connect_device(hdev);
2167         if (ret)
2168                 return ret;
2169
2170         if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
2171                 connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
2172         if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
2173                 connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
2174         if (hdev->bus != BUS_USB)
2175                 connect_mask &= ~HID_CONNECT_HIDDEV;
2176         if (hid_hiddev(hdev))
2177                 connect_mask |= HID_CONNECT_HIDDEV_FORCE;
2178
2179         if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
2180                                 connect_mask & HID_CONNECT_HIDINPUT_FORCE))
2181                 hdev->claimed |= HID_CLAIMED_INPUT;
2182
2183         if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
2184                         !hdev->hiddev_connect(hdev,
2185                                 connect_mask & HID_CONNECT_HIDDEV_FORCE))
2186                 hdev->claimed |= HID_CLAIMED_HIDDEV;
2187         if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
2188                 hdev->claimed |= HID_CLAIMED_HIDRAW;
2189
2190         if (connect_mask & HID_CONNECT_DRIVER)
2191                 hdev->claimed |= HID_CLAIMED_DRIVER;
2192
2193         /* Drivers with the ->raw_event callback set are not required to connect
2194          * to any other listener. */
2195         if (!hdev->claimed && !hdev->driver->raw_event) {
2196                 hid_err(hdev, "device has no listeners, quitting\n");
2197                 return -ENODEV;
2198         }
2199
2200         hid_process_ordering(hdev);
2201
2202         if ((hdev->claimed & HID_CLAIMED_INPUT) &&
2203                         (connect_mask & HID_CONNECT_FF) && hdev->ff_init)
2204                 hdev->ff_init(hdev);
2205
2206         len = 0;
2207         if (hdev->claimed & HID_CLAIMED_INPUT)
2208                 len += sprintf(buf + len, "input");
2209         if (hdev->claimed & HID_CLAIMED_HIDDEV)
2210                 len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
2211                                 ((struct hiddev *)hdev->hiddev)->minor);
2212         if (hdev->claimed & HID_CLAIMED_HIDRAW)
2213                 len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
2214                                 ((struct hidraw *)hdev->hidraw)->minor);
2215
2216         type = "Device";
2217         for (i = 0; i < hdev->maxcollection; i++) {
2218                 struct hid_collection *col = &hdev->collection[i];
2219                 if (col->type == HID_COLLECTION_APPLICATION &&
2220                    (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
2221                    (col->usage & 0xffff) < ARRAY_SIZE(types)) {
2222                         type = types[col->usage & 0xffff];
2223                         break;
2224                 }
2225         }
2226
2227         switch (hdev->bus) {
2228         case BUS_USB:
2229                 bus = "USB";
2230                 break;
2231         case BUS_BLUETOOTH:
2232                 bus = "BLUETOOTH";
2233                 break;
2234         case BUS_I2C:
2235                 bus = "I2C";
2236                 break;
2237         case BUS_VIRTUAL:
2238                 bus = "VIRTUAL";
2239                 break;
2240         case BUS_INTEL_ISHTP:
2241         case BUS_AMD_SFH:
2242                 bus = "SENSOR HUB";
2243                 break;
2244         default:
2245                 bus = "<UNKNOWN>";
2246         }
2247
2248         ret = device_create_file(&hdev->dev, &dev_attr_country);
2249         if (ret)
2250                 hid_warn(hdev,
2251                          "can't create sysfs country code attribute err: %d\n", ret);
2252
2253         hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
2254                  buf, bus, hdev->version >> 8, hdev->version & 0xff,
2255                  type, hdev->name, hdev->phys);
2256
2257         return 0;
2258 }
2259 EXPORT_SYMBOL_GPL(hid_connect);
2260
2261 void hid_disconnect(struct hid_device *hdev)
2262 {
2263         device_remove_file(&hdev->dev, &dev_attr_country);
2264         if (hdev->claimed & HID_CLAIMED_INPUT)
2265                 hidinput_disconnect(hdev);
2266         if (hdev->claimed & HID_CLAIMED_HIDDEV)
2267                 hdev->hiddev_disconnect(hdev);
2268         if (hdev->claimed & HID_CLAIMED_HIDRAW)
2269                 hidraw_disconnect(hdev);
2270         hdev->claimed = 0;
2271
2272         hid_bpf_disconnect_device(hdev);
2273 }
2274 EXPORT_SYMBOL_GPL(hid_disconnect);
2275
2276 /**
2277  * hid_hw_start - start underlying HW
2278  * @hdev: hid device
2279  * @connect_mask: which outputs to connect, see HID_CONNECT_*
2280  *
2281  * Call this in probe function *after* hid_parse. This will setup HW
2282  * buffers and start the device (if not defeirred to device open).
2283  * hid_hw_stop must be called if this was successful.
2284  */
2285 int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
2286 {
2287         int error;
2288
2289         error = hdev->ll_driver->start(hdev);
2290         if (error)
2291                 return error;
2292
2293         if (connect_mask) {
2294                 error = hid_connect(hdev, connect_mask);
2295                 if (error) {
2296                         hdev->ll_driver->stop(hdev);
2297                         return error;
2298                 }
2299         }
2300
2301         return 0;
2302 }
2303 EXPORT_SYMBOL_GPL(hid_hw_start);
2304
2305 /**
2306  * hid_hw_stop - stop underlying HW
2307  * @hdev: hid device
2308  *
2309  * This is usually called from remove function or from probe when something
2310  * failed and hid_hw_start was called already.
2311  */
2312 void hid_hw_stop(struct hid_device *hdev)
2313 {
2314         hid_disconnect(hdev);
2315         hdev->ll_driver->stop(hdev);
2316 }
2317 EXPORT_SYMBOL_GPL(hid_hw_stop);
2318
2319 /**
2320  * hid_hw_open - signal underlying HW to start delivering events
2321  * @hdev: hid device
2322  *
2323  * Tell underlying HW to start delivering events from the device.
2324  * This function should be called sometime after successful call
2325  * to hid_hw_start().
2326  */
2327 int hid_hw_open(struct hid_device *hdev)
2328 {
2329         int ret;
2330
2331         ret = mutex_lock_killable(&hdev->ll_open_lock);
2332         if (ret)
2333                 return ret;
2334
2335         if (!hdev->ll_open_count++) {
2336                 ret = hdev->ll_driver->open(hdev);
2337                 if (ret)
2338                         hdev->ll_open_count--;
2339         }
2340
2341         mutex_unlock(&hdev->ll_open_lock);
2342         return ret;
2343 }
2344 EXPORT_SYMBOL_GPL(hid_hw_open);
2345
2346 /**
2347  * hid_hw_close - signal underlaying HW to stop delivering events
2348  *
2349  * @hdev: hid device
2350  *
2351  * This function indicates that we are not interested in the events
2352  * from this device anymore. Delivery of events may or may not stop,
2353  * depending on the number of users still outstanding.
2354  */
2355 void hid_hw_close(struct hid_device *hdev)
2356 {
2357         mutex_lock(&hdev->ll_open_lock);
2358         if (!--hdev->ll_open_count)
2359                 hdev->ll_driver->close(hdev);
2360         mutex_unlock(&hdev->ll_open_lock);
2361 }
2362 EXPORT_SYMBOL_GPL(hid_hw_close);
2363
2364 /**
2365  * hid_hw_request - send report request to device
2366  *
2367  * @hdev: hid device
2368  * @report: report to send
2369  * @reqtype: hid request type
2370  */
2371 void hid_hw_request(struct hid_device *hdev,
2372                     struct hid_report *report, enum hid_class_request reqtype)
2373 {
2374         if (hdev->ll_driver->request)
2375                 return hdev->ll_driver->request(hdev, report, reqtype);
2376
2377         __hid_request(hdev, report, reqtype);
2378 }
2379 EXPORT_SYMBOL_GPL(hid_hw_request);
2380
2381 /**
2382  * hid_hw_raw_request - send report request to device
2383  *
2384  * @hdev: hid device
2385  * @reportnum: report ID
2386  * @buf: in/out data to transfer
2387  * @len: length of buf
2388  * @rtype: HID report type
2389  * @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT
2390  *
2391  * Return: count of data transferred, negative if error
2392  *
2393  * Same behavior as hid_hw_request, but with raw buffers instead.
2394  */
2395 int hid_hw_raw_request(struct hid_device *hdev,
2396                        unsigned char reportnum, __u8 *buf,
2397                        size_t len, enum hid_report_type rtype, enum hid_class_request reqtype)
2398 {
2399         if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
2400                 return -EINVAL;
2401
2402         return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
2403                                             rtype, reqtype);
2404 }
2405 EXPORT_SYMBOL_GPL(hid_hw_raw_request);
2406
2407 /**
2408  * hid_hw_output_report - send output report to device
2409  *
2410  * @hdev: hid device
2411  * @buf: raw data to transfer
2412  * @len: length of buf
2413  *
2414  * Return: count of data transferred, negative if error
2415  */
2416 int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
2417 {
2418         if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
2419                 return -EINVAL;
2420
2421         if (hdev->ll_driver->output_report)
2422                 return hdev->ll_driver->output_report(hdev, buf, len);
2423
2424         return -ENOSYS;
2425 }
2426 EXPORT_SYMBOL_GPL(hid_hw_output_report);
2427
2428 #ifdef CONFIG_PM
2429 int hid_driver_suspend(struct hid_device *hdev, pm_message_t state)
2430 {
2431         if (hdev->driver && hdev->driver->suspend)
2432                 return hdev->driver->suspend(hdev, state);
2433
2434         return 0;
2435 }
2436 EXPORT_SYMBOL_GPL(hid_driver_suspend);
2437
2438 int hid_driver_reset_resume(struct hid_device *hdev)
2439 {
2440         if (hdev->driver && hdev->driver->reset_resume)
2441                 return hdev->driver->reset_resume(hdev);
2442
2443         return 0;
2444 }
2445 EXPORT_SYMBOL_GPL(hid_driver_reset_resume);
2446
2447 int hid_driver_resume(struct hid_device *hdev)
2448 {
2449         if (hdev->driver && hdev->driver->resume)
2450                 return hdev->driver->resume(hdev);
2451
2452         return 0;
2453 }
2454 EXPORT_SYMBOL_GPL(hid_driver_resume);
2455 #endif /* CONFIG_PM */
2456
2457 struct hid_dynid {
2458         struct list_head list;
2459         struct hid_device_id id;
2460 };
2461
2462 /**
2463  * new_id_store - add a new HID device ID to this driver and re-probe devices
2464  * @drv: target device driver
2465  * @buf: buffer for scanning device ID data
2466  * @count: input size
2467  *
2468  * Adds a new dynamic hid device ID to this driver,
2469  * and causes the driver to probe for all devices again.
2470  */
2471 static ssize_t new_id_store(struct device_driver *drv, const char *buf,
2472                 size_t count)
2473 {
2474         struct hid_driver *hdrv = to_hid_driver(drv);
2475         struct hid_dynid *dynid;
2476         __u32 bus, vendor, product;
2477         unsigned long driver_data = 0;
2478         int ret;
2479
2480         ret = sscanf(buf, "%x %x %x %lx",
2481                         &bus, &vendor, &product, &driver_data);
2482         if (ret < 3)
2483                 return -EINVAL;
2484
2485         dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
2486         if (!dynid)
2487                 return -ENOMEM;
2488
2489         dynid->id.bus = bus;
2490         dynid->id.group = HID_GROUP_ANY;
2491         dynid->id.vendor = vendor;
2492         dynid->id.product = product;
2493         dynid->id.driver_data = driver_data;
2494
2495         spin_lock(&hdrv->dyn_lock);
2496         list_add_tail(&dynid->list, &hdrv->dyn_list);
2497         spin_unlock(&hdrv->dyn_lock);
2498
2499         ret = driver_attach(&hdrv->driver);
2500
2501         return ret ? : count;
2502 }
2503 static DRIVER_ATTR_WO(new_id);
2504
2505 static struct attribute *hid_drv_attrs[] = {
2506         &driver_attr_new_id.attr,
2507         NULL,
2508 };
2509 ATTRIBUTE_GROUPS(hid_drv);
2510
2511 static void hid_free_dynids(struct hid_driver *hdrv)
2512 {
2513         struct hid_dynid *dynid, *n;
2514
2515         spin_lock(&hdrv->dyn_lock);
2516         list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
2517                 list_del(&dynid->list);
2518                 kfree(dynid);
2519         }
2520         spin_unlock(&hdrv->dyn_lock);
2521 }
2522
2523 const struct hid_device_id *hid_match_device(struct hid_device *hdev,
2524                                              struct hid_driver *hdrv)
2525 {
2526         struct hid_dynid *dynid;
2527
2528         spin_lock(&hdrv->dyn_lock);
2529         list_for_each_entry(dynid, &hdrv->dyn_list, list) {
2530                 if (hid_match_one_id(hdev, &dynid->id)) {
2531                         spin_unlock(&hdrv->dyn_lock);
2532                         return &dynid->id;
2533                 }
2534         }
2535         spin_unlock(&hdrv->dyn_lock);
2536
2537         return hid_match_id(hdev, hdrv->id_table);
2538 }
2539 EXPORT_SYMBOL_GPL(hid_match_device);
2540
2541 static int hid_bus_match(struct device *dev, struct device_driver *drv)
2542 {
2543         struct hid_driver *hdrv = to_hid_driver(drv);
2544         struct hid_device *hdev = to_hid_device(dev);
2545
2546         return hid_match_device(hdev, hdrv) != NULL;
2547 }
2548
2549 /**
2550  * hid_compare_device_paths - check if both devices share the same path
2551  * @hdev_a: hid device
2552  * @hdev_b: hid device
2553  * @separator: char to use as separator
2554  *
2555  * Check if two devices share the same path up to the last occurrence of
2556  * the separator char. Both paths must exist (i.e., zero-length paths
2557  * don't match).
2558  */
2559 bool hid_compare_device_paths(struct hid_device *hdev_a,
2560                               struct hid_device *hdev_b, char separator)
2561 {
2562         int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
2563         int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
2564
2565         if (n1 != n2 || n1 <= 0 || n2 <= 0)
2566                 return false;
2567
2568         return !strncmp(hdev_a->phys, hdev_b->phys, n1);
2569 }
2570 EXPORT_SYMBOL_GPL(hid_compare_device_paths);
2571
2572 static int hid_device_probe(struct device *dev)
2573 {
2574         struct hid_driver *hdrv = to_hid_driver(dev->driver);
2575         struct hid_device *hdev = to_hid_device(dev);
2576         const struct hid_device_id *id;
2577         int ret = 0;
2578
2579         if (down_interruptible(&hdev->driver_input_lock)) {
2580                 ret = -EINTR;
2581                 goto end;
2582         }
2583         hdev->io_started = false;
2584
2585         clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
2586
2587         if (!hdev->driver) {
2588                 id = hid_match_device(hdev, hdrv);
2589                 if (id == NULL) {
2590                         ret = -ENODEV;
2591                         goto unlock;
2592                 }
2593
2594                 if (hdrv->match) {
2595                         if (!hdrv->match(hdev, hid_ignore_special_drivers)) {
2596                                 ret = -ENODEV;
2597                                 goto unlock;
2598                         }
2599                 } else {
2600                         /*
2601                          * hid-generic implements .match(), so if
2602                          * hid_ignore_special_drivers is set, we can safely
2603                          * return.
2604                          */
2605                         if (hid_ignore_special_drivers) {
2606                                 ret = -ENODEV;
2607                                 goto unlock;
2608                         }
2609                 }
2610
2611                 /* reset the quirks that has been previously set */
2612                 hdev->quirks = hid_lookup_quirk(hdev);
2613                 hdev->driver = hdrv;
2614                 if (hdrv->probe) {
2615                         ret = hdrv->probe(hdev, id);
2616                 } else { /* default probe */
2617                         ret = hid_open_report(hdev);
2618                         if (!ret)
2619                                 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
2620                 }
2621                 if (ret) {
2622                         hid_close_report(hdev);
2623                         hdev->driver = NULL;
2624                 }
2625         }
2626 unlock:
2627         if (!hdev->io_started)
2628                 up(&hdev->driver_input_lock);
2629 end:
2630         return ret;
2631 }
2632
2633 static void hid_device_remove(struct device *dev)
2634 {
2635         struct hid_device *hdev = to_hid_device(dev);
2636         struct hid_driver *hdrv;
2637
2638         down(&hdev->driver_input_lock);
2639         hdev->io_started = false;
2640
2641         hdrv = hdev->driver;
2642         if (hdrv) {
2643                 if (hdrv->remove)
2644                         hdrv->remove(hdev);
2645                 else /* default remove */
2646                         hid_hw_stop(hdev);
2647                 hid_close_report(hdev);
2648                 hdev->driver = NULL;
2649         }
2650
2651         if (!hdev->io_started)
2652                 up(&hdev->driver_input_lock);
2653 }
2654
2655 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
2656                              char *buf)
2657 {
2658         struct hid_device *hdev = container_of(dev, struct hid_device, dev);
2659
2660         return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n",
2661                          hdev->bus, hdev->group, hdev->vendor, hdev->product);
2662 }
2663 static DEVICE_ATTR_RO(modalias);
2664
2665 static struct attribute *hid_dev_attrs[] = {
2666         &dev_attr_modalias.attr,
2667         NULL,
2668 };
2669 static struct bin_attribute *hid_dev_bin_attrs[] = {
2670         &dev_bin_attr_report_desc,
2671         NULL
2672 };
2673 static const struct attribute_group hid_dev_group = {
2674         .attrs = hid_dev_attrs,
2675         .bin_attrs = hid_dev_bin_attrs,
2676 };
2677 __ATTRIBUTE_GROUPS(hid_dev);
2678
2679 static int hid_uevent(struct device *dev, struct kobj_uevent_env *env)
2680 {
2681         struct hid_device *hdev = to_hid_device(dev);
2682
2683         if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
2684                         hdev->bus, hdev->vendor, hdev->product))
2685                 return -ENOMEM;
2686
2687         if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
2688                 return -ENOMEM;
2689
2690         if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
2691                 return -ENOMEM;
2692
2693         if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
2694                 return -ENOMEM;
2695
2696         if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
2697                            hdev->bus, hdev->group, hdev->vendor, hdev->product))
2698                 return -ENOMEM;
2699
2700         return 0;
2701 }
2702
2703 struct bus_type hid_bus_type = {
2704         .name           = "hid",
2705         .dev_groups     = hid_dev_groups,
2706         .drv_groups     = hid_drv_groups,
2707         .match          = hid_bus_match,
2708         .probe          = hid_device_probe,
2709         .remove         = hid_device_remove,
2710         .uevent         = hid_uevent,
2711 };
2712 EXPORT_SYMBOL(hid_bus_type);
2713
2714 int hid_add_device(struct hid_device *hdev)
2715 {
2716         static atomic_t id = ATOMIC_INIT(0);
2717         int ret;
2718
2719         if (WARN_ON(hdev->status & HID_STAT_ADDED))
2720                 return -EBUSY;
2721
2722         hdev->quirks = hid_lookup_quirk(hdev);
2723
2724         /* we need to kill them here, otherwise they will stay allocated to
2725          * wait for coming driver */
2726         if (hid_ignore(hdev))
2727                 return -ENODEV;
2728
2729         /*
2730          * Check for the mandatory transport channel.
2731          */
2732          if (!hdev->ll_driver->raw_request) {
2733                 hid_err(hdev, "transport driver missing .raw_request()\n");
2734                 return -EINVAL;
2735          }
2736
2737         /*
2738          * Read the device report descriptor once and use as template
2739          * for the driver-specific modifications.
2740          */
2741         ret = hdev->ll_driver->parse(hdev);
2742         if (ret)
2743                 return ret;
2744         if (!hdev->dev_rdesc)
2745                 return -ENODEV;
2746
2747         /*
2748          * Scan generic devices for group information
2749          */
2750         if (hid_ignore_special_drivers) {
2751                 hdev->group = HID_GROUP_GENERIC;
2752         } else if (!hdev->group &&
2753                    !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
2754                 ret = hid_scan_report(hdev);
2755                 if (ret)
2756                         hid_warn(hdev, "bad device descriptor (%d)\n", ret);
2757         }
2758
2759         hdev->id = atomic_inc_return(&id);
2760
2761         /* XXX hack, any other cleaner solution after the driver core
2762          * is converted to allow more than 20 bytes as the device name? */
2763         dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
2764                      hdev->vendor, hdev->product, hdev->id);
2765
2766         hid_debug_register(hdev, dev_name(&hdev->dev));
2767         ret = device_add(&hdev->dev);
2768         if (!ret)
2769                 hdev->status |= HID_STAT_ADDED;
2770         else
2771                 hid_debug_unregister(hdev);
2772
2773         return ret;
2774 }
2775 EXPORT_SYMBOL_GPL(hid_add_device);
2776
2777 /**
2778  * hid_allocate_device - allocate new hid device descriptor
2779  *
2780  * Allocate and initialize hid device, so that hid_destroy_device might be
2781  * used to free it.
2782  *
2783  * New hid_device pointer is returned on success, otherwise ERR_PTR encoded
2784  * error value.
2785  */
2786 struct hid_device *hid_allocate_device(void)
2787 {
2788         struct hid_device *hdev;
2789         int ret = -ENOMEM;
2790
2791         hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
2792         if (hdev == NULL)
2793                 return ERR_PTR(ret);
2794
2795         device_initialize(&hdev->dev);
2796         hdev->dev.release = hid_device_release;
2797         hdev->dev.bus = &hid_bus_type;
2798         device_enable_async_suspend(&hdev->dev);
2799
2800         hid_close_report(hdev);
2801
2802         init_waitqueue_head(&hdev->debug_wait);
2803         INIT_LIST_HEAD(&hdev->debug_list);
2804         spin_lock_init(&hdev->debug_list_lock);
2805         sema_init(&hdev->driver_input_lock, 1);
2806         mutex_init(&hdev->ll_open_lock);
2807
2808         hid_bpf_device_init(hdev);
2809
2810         return hdev;
2811 }
2812 EXPORT_SYMBOL_GPL(hid_allocate_device);
2813
2814 static void hid_remove_device(struct hid_device *hdev)
2815 {
2816         if (hdev->status & HID_STAT_ADDED) {
2817                 device_del(&hdev->dev);
2818                 hid_debug_unregister(hdev);
2819                 hdev->status &= ~HID_STAT_ADDED;
2820         }
2821         kfree(hdev->dev_rdesc);
2822         hdev->dev_rdesc = NULL;
2823         hdev->dev_rsize = 0;
2824 }
2825
2826 /**
2827  * hid_destroy_device - free previously allocated device
2828  *
2829  * @hdev: hid device
2830  *
2831  * If you allocate hid_device through hid_allocate_device, you should ever
2832  * free by this function.
2833  */
2834 void hid_destroy_device(struct hid_device *hdev)
2835 {
2836         hid_bpf_destroy_device(hdev);
2837         hid_remove_device(hdev);
2838         put_device(&hdev->dev);
2839 }
2840 EXPORT_SYMBOL_GPL(hid_destroy_device);
2841
2842
2843 static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
2844 {
2845         struct hid_driver *hdrv = data;
2846         struct hid_device *hdev = to_hid_device(dev);
2847
2848         if (hdev->driver == hdrv &&
2849             !hdrv->match(hdev, hid_ignore_special_drivers) &&
2850             !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
2851                 return device_reprobe(dev);
2852
2853         return 0;
2854 }
2855
2856 static int __hid_bus_driver_added(struct device_driver *drv, void *data)
2857 {
2858         struct hid_driver *hdrv = to_hid_driver(drv);
2859
2860         if (hdrv->match) {
2861                 bus_for_each_dev(&hid_bus_type, NULL, hdrv,
2862                                  __hid_bus_reprobe_drivers);
2863         }
2864
2865         return 0;
2866 }
2867
2868 static int __bus_removed_driver(struct device_driver *drv, void *data)
2869 {
2870         return bus_rescan_devices(&hid_bus_type);
2871 }
2872
2873 int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
2874                 const char *mod_name)
2875 {
2876         int ret;
2877
2878         hdrv->driver.name = hdrv->name;
2879         hdrv->driver.bus = &hid_bus_type;
2880         hdrv->driver.owner = owner;
2881         hdrv->driver.mod_name = mod_name;
2882
2883         INIT_LIST_HEAD(&hdrv->dyn_list);
2884         spin_lock_init(&hdrv->dyn_lock);
2885
2886         ret = driver_register(&hdrv->driver);
2887
2888         if (ret == 0)
2889                 bus_for_each_drv(&hid_bus_type, NULL, NULL,
2890                                  __hid_bus_driver_added);
2891
2892         return ret;
2893 }
2894 EXPORT_SYMBOL_GPL(__hid_register_driver);
2895
2896 void hid_unregister_driver(struct hid_driver *hdrv)
2897 {
2898         driver_unregister(&hdrv->driver);
2899         hid_free_dynids(hdrv);
2900
2901         bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
2902 }
2903 EXPORT_SYMBOL_GPL(hid_unregister_driver);
2904
2905 int hid_check_keys_pressed(struct hid_device *hid)
2906 {
2907         struct hid_input *hidinput;
2908         int i;
2909
2910         if (!(hid->claimed & HID_CLAIMED_INPUT))
2911                 return 0;
2912
2913         list_for_each_entry(hidinput, &hid->inputs, list) {
2914                 for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
2915                         if (hidinput->input->key[i])
2916                                 return 1;
2917         }
2918
2919         return 0;
2920 }
2921 EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
2922
2923 #ifdef CONFIG_HID_BPF
2924 static struct hid_bpf_ops hid_ops = {
2925         .hid_get_report = hid_get_report,
2926         .hid_hw_raw_request = hid_hw_raw_request,
2927         .owner = THIS_MODULE,
2928         .bus_type = &hid_bus_type,
2929 };
2930 #endif
2931
2932 static int __init hid_init(void)
2933 {
2934         int ret;
2935
2936         ret = bus_register(&hid_bus_type);
2937         if (ret) {
2938                 pr_err("can't register hid bus\n");
2939                 goto err;
2940         }
2941
2942 #ifdef CONFIG_HID_BPF
2943         hid_bpf_ops = &hid_ops;
2944 #endif
2945
2946         ret = hidraw_init();
2947         if (ret)
2948                 goto err_bus;
2949
2950         hid_debug_init();
2951
2952         return 0;
2953 err_bus:
2954         bus_unregister(&hid_bus_type);
2955 err:
2956         return ret;
2957 }
2958
2959 static void __exit hid_exit(void)
2960 {
2961 #ifdef CONFIG_HID_BPF
2962         hid_bpf_ops = NULL;
2963 #endif
2964         hid_debug_exit();
2965         hidraw_exit();
2966         bus_unregister(&hid_bus_type);
2967         hid_quirks_exit(HID_BUS_ANY);
2968 }
2969
2970 module_init(hid_init);
2971 module_exit(hid_exit);
2972
2973 MODULE_AUTHOR("Andreas Gal");
2974 MODULE_AUTHOR("Vojtech Pavlik");
2975 MODULE_AUTHOR("Jiri Kosina");
2976 MODULE_LICENSE("GPL");