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 int hid_debug = 0;
  45 module_param_named(debug, hid_debug, int, 0600);
  46 MODULE_PARM_DESC(debug, "toggle HID debugging messages");
  47 EXPORT_SYMBOL_GPL(hid_debug);
  48
  49 static int hid_ignore_special_drivers = 0;
  50 module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
  51 MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
  52
  53 /*
  54  * Register a new report for a device.
  55  */
  56
  57 struct hid_report *hid_register_report(struct hid_device *device,
  58                                        enum hid_report_type type, unsigned int id,
  59                                        unsigned int application)
  60 {
  61         struct hid_report_enum *report_enum = device->report_enum + type;
  62         struct hid_report *report;
  63
  64         if (id >= HID_MAX_IDS)
  65                 return NULL;
  66         if (report_enum->report_id_hash[id])
  67                 return report_enum->report_id_hash[id];
  68
  69         report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
  70         if (!report)
  71                 return NULL;
  72
  73         if (id != 0)
  74                 report_enum->numbered = 1;
  75
  76         report->id = id;
  77         report->type = type;
  78         report->size = 0;
  79         report->device = device;
  80         report->application = application;
  81         report_enum->report_id_hash[id] = report;
  82
  83         list_add_tail(&report->list, &report_enum->report_list);
  84         INIT_LIST_HEAD(&report->field_entry_list);
  85
  86         return report;
  87 }
  88 EXPORT_SYMBOL_GPL(hid_register_report);
  89
  90 /*
  91  * Register a new field for this report.
  92  */
  93
  94 static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages)
  95 {
  96         struct hid_field *field;
  97
  98         if (report->maxfield == HID_MAX_FIELDS) {
  99                 hid_err(report->device, "too many fields in report\n");
 100                 return NULL;
 101         }
 102
 103         field = kzalloc((sizeof(struct hid_field) +
 104                          usages * sizeof(struct hid_usage) +
 105                          3 * usages * sizeof(unsigned int)), GFP_KERNEL);
 106         if (!field)
 107                 return NULL;
 108
 109         field->index = report->maxfield++;
 110         report->field[field->index] = field;
 111         field->usage = (struct hid_usage *)(field + 1);
 112         field->value = (s32 *)(field->usage + usages);
 113         field->new_value = (s32 *)(field->value + usages);
 114         field->usages_priorities = (s32 *)(field->new_value + usages);
 115         field->report = report;
 116
 117         return field;
 118 }
 119
 120 /*
 121  * Open a collection. The type/usage is pushed on the stack.
 122  */
 123
 124 static int open_collection(struct hid_parser *parser, unsigned type)
 125 {
 126         struct hid_collection *collection;
 127         unsigned usage;
 128         int collection_index;
 129
 130         usage = parser->local.usage[0];
 131
 132         if (parser->collection_stack_ptr == parser->collection_stack_size) {
 133                 unsigned int *collection_stack;
 134                 unsigned int new_size = parser->collection_stack_size +
 135                                         HID_COLLECTION_STACK_SIZE;
 136
 137                 collection_stack = krealloc(parser->collection_stack,
 138                                             new_size * sizeof(unsigned int),
 139                                             GFP_KERNEL);
 140                 if (!collection_stack)
 141                         return -ENOMEM;
 142
 143                 parser->collection_stack = collection_stack;
 144                 parser->collection_stack_size = new_size;
 145         }
 146
 147         if (parser->device->maxcollection == parser->device->collection_size) {
 148                 collection = kmalloc(
 149                                 array3_size(sizeof(struct hid_collection),
 150                                             parser->device->collection_size,
 151                                             2),
 152                                 GFP_KERNEL);
 153                 if (collection == NULL) {
 154                         hid_err(parser->device, "failed to reallocate collection array\n");
 155                         return -ENOMEM;
 156                 }
 157                 memcpy(collection, parser->device->collection,
 158                         sizeof(struct hid_collection) *
 159                         parser->device->collection_size);
 160                 memset(collection + parser->device->collection_size, 0,
 161                         sizeof(struct hid_collection) *
 162                         parser->device->collection_size);
 163                 kfree(parser->device->collection);
 164                 parser->device->collection = collection;
 165                 parser->device->collection_size *= 2;
 166         }
 167
 168         parser->collection_stack[parser->collection_stack_ptr++] =
 169                 parser->device->maxcollection;
 170
 171         collection_index = parser->device->maxcollection++;
 172         collection = parser->device->collection + collection_index;
 173         collection->type = type;
 174         collection->usage = usage;
 175         collection->level = parser->collection_stack_ptr - 1;
 176         collection->parent_idx = (collection->level == 0) ? -1 :
 177                 parser->collection_stack[collection->level - 1];
 178
 179         if (type == HID_COLLECTION_APPLICATION)
 180                 parser->device->maxapplication++;
 181
 182         return 0;
 183 }
 184
 185 /*
 186  * Close a collection.
 187  */
 188
 189 static int close_collection(struct hid_parser *parser)
 190 {
 191         if (!parser->collection_stack_ptr) {
 192                 hid_err(parser->device, "collection stack underflow\n");
 193                 return -EINVAL;
 194         }
 195         parser->collection_stack_ptr--;
 196         return 0;
 197 }
 198
 199 /*
 200  * Climb up the stack, search for the specified collection type
 201  * and return the usage.
 202  */
 203
 204 static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
 205 {
 206         struct hid_collection *collection = parser->device->collection;
 207         int n;
 208
 209         for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
 210                 unsigned index = parser->collection_stack[n];
 211                 if (collection[index].type == type)
 212                         return collection[index].usage;
 213         }
 214         return 0; /* we know nothing about this usage type */
 215 }
 216
 217 /*
 218  * Concatenate usage which defines 16 bits or less with the
 219  * currently defined usage page to form a 32 bit usage
 220  */
 221
 222 static void complete_usage(struct hid_parser *parser, unsigned int index)
 223 {
 224         parser->local.usage[index] &= 0xFFFF;
 225         parser->local.usage[index] |=
 226                 (parser->global.usage_page & 0xFFFF) << 16;
 227 }
 228
 229 /*
 230  * Add a usage to the temporary parser table.
 231  */
 232
 233 static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
 234 {
 235         if (parser->local.usage_index >= HID_MAX_USAGES) {
 236                 hid_err(parser->device, "usage index exceeded\n");
 237                 return -1;
 238         }
 239         parser->local.usage[parser->local.usage_index] = usage;
 240
 241         /*
 242          * If Usage item only includes usage id, concatenate it with
 243          * currently defined usage page
 244          */
 245         if (size <= 2)
 246                 complete_usage(parser, parser->local.usage_index);
 247
 248         parser->local.usage_size[parser->local.usage_index] = size;
 249         parser->local.collection_index[parser->local.usage_index] =
 250                 parser->collection_stack_ptr ?
 251                 parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
 252         parser->local.usage_index++;
 253         return 0;
 254 }
 255
 256 /*
 257  * Register a new field for this report.
 258  */
 259
 260 static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
 261 {
 262         struct hid_report *report;
 263         struct hid_field *field;
 264         unsigned int usages;
 265         unsigned int offset;
 266         unsigned int i;
 267         unsigned int application;
 268
 269         application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
 270
 271         report = hid_register_report(parser->device, report_type,
 272                                      parser->global.report_id, application);
 273         if (!report) {
 274                 hid_err(parser->device, "hid_register_report failed\n");
 275                 return -1;
 276         }
 277
 278         /* Handle both signed and unsigned cases properly */
 279         if ((parser->global.logical_minimum < 0 &&
 280                 parser->global.logical_maximum <
 281                 parser->global.logical_minimum) ||
 282                 (parser->global.logical_minimum >= 0 &&
 283                 (__u32)parser->global.logical_maximum <
 284                 (__u32)parser->global.logical_minimum)) {
 285                 dbg_hid("logical range invalid 0x%x 0x%x\n",
 286                         parser->global.logical_minimum,
 287                         parser->global.logical_maximum);
 288                 return -1;
 289         }
 290
 291         offset = report->size;
 292         report->size += parser->global.report_size * parser->global.report_count;
 293
 294         /* Total size check: Allow for possible report index byte */
 295         if (report->size > (HID_MAX_BUFFER_SIZE - 1) << 3) {
 296                 hid_err(parser->device, "report is too long\n");
 297                 return -1;
 298         }
 299
 300         if (!parser->local.usage_index) /* Ignore padding fields */
 301                 return 0;
 302
 303         usages = max_t(unsigned, parser->local.usage_index,
 304                                  parser->global.report_count);
 305
 306         field = hid_register_field(report, usages);
 307         if (!field)
 308                 return 0;
 309
 310         field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
 311         field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
 312         field->application = application;
 313
 314         for (i = 0; i < usages; i++) {
 315                 unsigned j = i;
 316                 /* Duplicate the last usage we parsed if we have excess values */
 317                 if (i >= parser->local.usage_index)
 318                         j = parser->local.usage_index - 1;
 319                 field->usage[i].hid = parser->local.usage[j];
 320                 field->usage[i].collection_index =
 321                         parser->local.collection_index[j];
 322                 field->usage[i].usage_index = i;
 323                 field->usage[i].resolution_multiplier = 1;
 324         }
 325
 326         field->maxusage = usages;
 327         field->flags = flags;
 328         field->report_offset = offset;
 329         field->report_type = report_type;
 330         field->report_size = parser->global.report_size;
 331         field->report_count = parser->global.report_count;
 332         field->logical_minimum = parser->global.logical_minimum;
 333         field->logical_maximum = parser->global.logical_maximum;
 334         field->physical_minimum = parser->global.physical_minimum;
 335         field->physical_maximum = parser->global.physical_maximum;
 336         field->unit_exponent = parser->global.unit_exponent;
 337         field->unit = parser->global.unit;
 338
 339         return 0;
 340 }
 341
 342 /*
 343  * Read data value from item.
 344  */
 345
 346 static u32 item_udata(struct hid_item *item)
 347 {
 348         switch (item->size) {
 349         case 1: return item->data.u8;
 350         case 2: return item->data.u16;
 351         case 4: return item->data.u32;
 352         }
 353         return 0;
 354 }
 355
 356 static s32 item_sdata(struct hid_item *item)
 357 {
 358         switch (item->size) {
 359         case 1: return item->data.s8;
 360         case 2: return item->data.s16;
 361         case 4: return item->data.s32;
 362         }
 363         return 0;
 364 }
 365
 366 /*
 367  * Process a global item.
 368  */
 369
 370 static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
 371 {
 372         __s32 raw_value;
 373         switch (item->tag) {
 374         case HID_GLOBAL_ITEM_TAG_PUSH:
 375
 376                 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
 377                         hid_err(parser->device, "global environment stack overflow\n");
 378                         return -1;
 379                 }
 380
 381                 memcpy(parser->global_stack + parser->global_stack_ptr++,
 382                         &parser->global, sizeof(struct hid_global));
 383                 return 0;
 384
 385         case HID_GLOBAL_ITEM_TAG_POP:
 386
 387                 if (!parser->global_stack_ptr) {
 388                         hid_err(parser->device, "global environment stack underflow\n");
 389                         return -1;
 390                 }
 391
 392                 memcpy(&parser->global, parser->global_stack +
 393                         --parser->global_stack_ptr, sizeof(struct hid_global));
 394                 return 0;
 395
 396         case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
 397                 parser->global.usage_page = item_udata(item);
 398                 return 0;
 399
 400         case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
 401                 parser->global.logical_minimum = item_sdata(item);
 402                 return 0;
 403
 404         case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
 405                 if (parser->global.logical_minimum < 0)
 406                         parser->global.logical_maximum = item_sdata(item);
 407                 else
 408                         parser->global.logical_maximum = item_udata(item);
 409                 return 0;
 410
 411         case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
 412                 parser->global.physical_minimum = item_sdata(item);
 413                 return 0;
 414
 415         case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
 416                 if (parser->global.physical_minimum < 0)
 417                         parser->global.physical_maximum = item_sdata(item);
 418                 else
 419                         parser->global.physical_maximum = item_udata(item);
 420                 return 0;
 421
 422         case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
 423                 /* Many devices provide unit exponent as a two's complement
 424                  * nibble due to the common misunderstanding of HID
 425                  * specification 1.11, 6.2.2.7 Global Items. Attempt to handle
 426                  * both this and the standard encoding. */
 427                 raw_value = item_sdata(item);
 428                 if (!(raw_value & 0xfffffff0))
 429                         parser->global.unit_exponent = hid_snto32(raw_value, 4);
 430                 else
 431                         parser->global.unit_exponent = raw_value;
 432                 return 0;
 433
 434         case HID_GLOBAL_ITEM_TAG_UNIT:
 435                 parser->global.unit = item_udata(item);
 436                 return 0;
 437
 438         case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
 439                 parser->global.report_size = item_udata(item);
 440                 if (parser->global.report_size > 256) {
 441                         hid_err(parser->device, "invalid report_size %d\n",
 442                                         parser->global.report_size);
 443                         return -1;
 444                 }
 445                 return 0;
 446
 447         case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
 448                 parser->global.report_count = item_udata(item);
 449                 if (parser->global.report_count > HID_MAX_USAGES) {
 450                         hid_err(parser->device, "invalid report_count %d\n",
 451                                         parser->global.report_count);
 452                         return -1;
 453                 }
 454                 return 0;
 455
 456         case HID_GLOBAL_ITEM_TAG_REPORT_ID:
 457                 parser->global.report_id = item_udata(item);
 458                 if (parser->global.report_id == 0 ||
 459                     parser->global.report_id >= HID_MAX_IDS) {
 460                         hid_err(parser->device, "report_id %u is invalid\n",
 461                                 parser->global.report_id);
 462                         return -1;
 463                 }
 464                 return 0;
 465
 466         default:
 467                 hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
 468                 return -1;
 469         }
 470 }
 471
 472 /*
 473  * Process a local item.
 474  */
 475
 476 static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
 477 {
 478         __u32 data;
 479         unsigned n;
 480         __u32 count;
 481
 482         data = item_udata(item);
 483
 484         switch (item->tag) {
 485         case HID_LOCAL_ITEM_TAG_DELIMITER:
 486
 487                 if (data) {
 488                         /*
 489                          * We treat items before the first delimiter
 490                          * as global to all usage sets (branch 0).
 491                          * In the moment we process only these global
 492                          * items and the first delimiter set.
 493                          */
 494                         if (parser->local.delimiter_depth != 0) {
 495                                 hid_err(parser->device, "nested delimiters\n");
 496                                 return -1;
 497                         }
 498                         parser->local.delimiter_depth++;
 499                         parser->local.delimiter_branch++;
 500                 } else {
 501                         if (parser->local.delimiter_depth < 1) {
 502                                 hid_err(parser->device, "bogus close delimiter\n");
 503                                 return -1;
 504                         }
 505                         parser->local.delimiter_depth--;
 506                 }
 507                 return 0;
 508
 509         case HID_LOCAL_ITEM_TAG_USAGE:
 510
 511                 if (parser->local.delimiter_branch > 1) {
 512                         dbg_hid("alternative usage ignored\n");
 513                         return 0;
 514                 }
 515
 516                 return hid_add_usage(parser, data, item->size);
 517
 518         case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
 519
 520                 if (parser->local.delimiter_branch > 1) {
 521                         dbg_hid("alternative usage ignored\n");
 522                         return 0;
 523                 }
 524
 525                 parser->local.usage_minimum = data;
 526                 return 0;
 527
 528         case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
 529
 530                 if (parser->local.delimiter_branch > 1) {
 531                         dbg_hid("alternative usage ignored\n");
 532                         return 0;
 533                 }
 534
 535                 count = data - parser->local.usage_minimum;
 536                 if (count + parser->local.usage_index >= HID_MAX_USAGES) {
 537                         /*
 538                          * We do not warn if the name is not set, we are
 539                          * actually pre-scanning the device.
 540                          */
 541                         if (dev_name(&parser->device->dev))
 542                                 hid_warn(parser->device,
 543                                          "ignoring exceeding usage max\n");
 544                         data = HID_MAX_USAGES - parser->local.usage_index +
 545                                 parser->local.usage_minimum - 1;
 546                         if (data <= 0) {
 547                                 hid_err(parser->device,
 548                                         "no more usage index available\n");
 549                                 return -1;
 550                         }
 551                 }
 552
 553                 for (n = parser->local.usage_minimum; n <= data; n++)
 554                         if (hid_add_usage(parser, n, item->size)) {
 555                                 dbg_hid("hid_add_usage failed\n");
 556                                 return -1;
 557                         }
 558                 return 0;
 559
 560         default:
 561
 562                 dbg_hid("unknown local item tag 0x%x\n", item->tag);
 563                 return 0;
 564         }
 565         return 0;
 566 }
 567
 568 /*
 569  * Concatenate Usage Pages into Usages where relevant:
 570  * As per specification, 6.2.2.8: "When the parser encounters a main item it
 571  * concatenates the last declared Usage Page with a Usage to form a complete
 572  * usage value."
 573  */
 574
 575 static void hid_concatenate_last_usage_page(struct hid_parser *parser)
 576 {
 577         int i;
 578         unsigned int usage_page;
 579         unsigned int current_page;
 580
 581         if (!parser->local.usage_index)
 582                 return;
 583
 584         usage_page = parser->global.usage_page;
 585
 586         /*
 587          * Concatenate usage page again only if last declared Usage Page
 588          * has not been already used in previous usages concatenation
 589          */
 590         for (i = parser->local.usage_index - 1; i >= 0; i--) {
 591                 if (parser->local.usage_size[i] > 2)
 592                         /* Ignore extended usages */
 593                         continue;
 594
 595                 current_page = parser->local.usage[i] >> 16;
 596                 if (current_page == usage_page)
 597                         break;
 598
 599                 complete_usage(parser, i);
 600         }
 601 }
 602
 603 /*
 604  * Process a main item.
 605  */
 606
 607 static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
 608 {
 609         __u32 data;
 610         int ret;
 611
 612         hid_concatenate_last_usage_page(parser);
 613
 614         data = item_udata(item);
 615
 616         switch (item->tag) {
 617         case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 618                 ret = open_collection(parser, data & 0xff);
 619                 break;
 620         case HID_MAIN_ITEM_TAG_END_COLLECTION:
 621                 ret = close_collection(parser);
 622                 break;
 623         case HID_MAIN_ITEM_TAG_INPUT:
 624                 ret = hid_add_field(parser, HID_INPUT_REPORT, data);
 625                 break;
 626         case HID_MAIN_ITEM_TAG_OUTPUT:
 627                 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
 628                 break;
 629         case HID_MAIN_ITEM_TAG_FEATURE:
 630                 ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
 631                 break;
 632         default:
 633                 hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag);
 634                 ret = 0;
 635         }
 636
 637         memset(&parser->local, 0, sizeof(parser->local));       /* Reset the local parser environment */
 638
 639         return ret;
 640 }
 641
 642 /*
 643  * Process a reserved item.
 644  */
 645
 646 static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
 647 {
 648         dbg_hid("reserved item type, tag 0x%x\n", item->tag);
 649         return 0;
 650 }
 651
 652 /*
 653  * Free a report and all registered fields. The field->usage and
 654  * field->value table's are allocated behind the field, so we need
 655  * only to free(field) itself.
 656  */
 657
 658 static void hid_free_report(struct hid_report *report)
 659 {
 660         unsigned n;
 661
 662         kfree(report->field_entries);
 663
 664         for (n = 0; n < report->maxfield; n++)
 665                 kfree(report->field[n]);
 666         kfree(report);
 667 }
 668
 669 /*
 670  * Close report. This function returns the device
 671  * state to the point prior to hid_open_report().
 672  */
 673 static void hid_close_report(struct hid_device *device)
 674 {
 675         unsigned i, j;
 676
 677         for (i = 0; i < HID_REPORT_TYPES; i++) {
 678                 struct hid_report_enum *report_enum = device->report_enum + i;
 679
 680                 for (j = 0; j < HID_MAX_IDS; j++) {
 681                         struct hid_report *report = report_enum->report_id_hash[j];
 682                         if (report)
 683                                 hid_free_report(report);
 684                 }
 685                 memset(report_enum, 0, sizeof(*report_enum));
 686                 INIT_LIST_HEAD(&report_enum->report_list);
 687         }
 688
 689         kfree(device->rdesc);
 690         device->rdesc = NULL;
 691         device->rsize = 0;
 692
 693         kfree(device->collection);
 694         device->collection = NULL;
 695         device->collection_size = 0;
 696         device->maxcollection = 0;
 697         device->maxapplication = 0;
 698
 699         device->status &= ~HID_STAT_PARSED;
 700 }
 701
 702 /*
 703  * Free a device structure, all reports, and all fields.
 704  */
 705
 706 static void hid_device_release(struct device *dev)
 707 {
 708         struct hid_device *hid = to_hid_device(dev);
 709
 710         hid_close_report(hid);
 711         kfree(hid->dev_rdesc);
 712         kfree(hid);
 713 }
 714
 715 /*
 716  * Fetch a report description item from the data stream. We support long
 717  * items, though they are not used yet.
 718  */
 719
 720 static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
 721 {
 722         u8 b;
 723
 724         if ((end - start) <= 0)
 725                 return NULL;
 726
 727         b = *start++;
 728
 729         item->type = (b >> 2) & 3;
 730         item->tag  = (b >> 4) & 15;
 731
 732         if (item->tag == HID_ITEM_TAG_LONG) {
 733
 734                 item->format = HID_ITEM_FORMAT_LONG;
 735
 736                 if ((end - start) < 2)
 737                         return NULL;
 738
 739                 item->size = *start++;
 740                 item->tag  = *start++;
 741
 742                 if ((end - start) < item->size)
 743                         return NULL;
 744
 745                 item->data.longdata = start;
 746                 start += item->size;
 747                 return start;
 748         }
 749
 750         item->format = HID_ITEM_FORMAT_SHORT;
 751         item->size = b & 3;
 752
 753         switch (item->size) {
 754         case 0:
 755                 return start;
 756
 757         case 1:
 758                 if ((end - start) < 1)
 759                         return NULL;
 760                 item->data.u8 = *start++;
 761                 return start;
 762
 763         case 2:
 764                 if ((end - start) < 2)
 765                         return NULL;
 766                 item->data.u16 = get_unaligned_le16(start);
 767                 start = (__u8 *)((__le16 *)start + 1);
 768                 return start;
 769
 770         case 3:
 771                 item->size++;
 772                 if ((end - start) < 4)
 773                         return NULL;
 774                 item->data.u32 = get_unaligned_le32(start);
 775                 start = (__u8 *)((__le32 *)start + 1);
 776                 return start;
 777         }
 778
 779         return NULL;
 780 }
 781
 782 static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
 783 {
 784         struct hid_device *hid = parser->device;
 785
 786         if (usage == HID_DG_CONTACTID)
 787                 hid->group = HID_GROUP_MULTITOUCH;
 788 }
 789
 790 static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
 791 {
 792         if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
 793             parser->global.report_size == 8)
 794                 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 795
 796         if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
 797             parser->global.report_size == 8)
 798                 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 799 }
 800
 801 static void hid_scan_collection(struct hid_parser *parser, unsigned type)
 802 {
 803         struct hid_device *hid = parser->device;
 804         int i;
 805
 806         if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
 807             type == HID_COLLECTION_PHYSICAL)
 808                 hid->group = HID_GROUP_SENSOR_HUB;
 809
 810         if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
 811             hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
 812             hid->group == HID_GROUP_MULTITOUCH)
 813                 hid->group = HID_GROUP_GENERIC;
 814
 815         if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
 816                 for (i = 0; i < parser->local.usage_index; i++)
 817                         if (parser->local.usage[i] == HID_GD_POINTER)
 818                                 parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
 819
 820         if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
 821                 parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
 822
 823         if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR)
 824                 for (i = 0; i < parser->local.usage_index; i++)
 825                         if (parser->local.usage[i] ==
 826                                         (HID_UP_GOOGLEVENDOR | 0x0001))
 827                                 parser->device->group =
 828                                         HID_GROUP_VIVALDI;
 829 }
 830
 831 static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
 832 {
 833         __u32 data;
 834         int i;
 835
 836         hid_concatenate_last_usage_page(parser);
 837
 838         data = item_udata(item);
 839
 840         switch (item->tag) {
 841         case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
 842                 hid_scan_collection(parser, data & 0xff);
 843                 break;
 844         case HID_MAIN_ITEM_TAG_END_COLLECTION:
 845                 break;
 846         case HID_MAIN_ITEM_TAG_INPUT:
 847                 /* ignore constant inputs, they will be ignored by hid-input */
 848                 if (data & HID_MAIN_ITEM_CONSTANT)
 849                         break;
 850                 for (i = 0; i < parser->local.usage_index; i++)
 851                         hid_scan_input_usage(parser, parser->local.usage[i]);
 852                 break;
 853         case HID_MAIN_ITEM_TAG_OUTPUT:
 854                 break;
 855         case HID_MAIN_ITEM_TAG_FEATURE:
 856                 for (i = 0; i < parser->local.usage_index; i++)
 857                         hid_scan_feature_usage(parser, parser->local.usage[i]);
 858                 break;
 859         }
 860
 861         /* Reset the local parser environment */
 862         memset(&parser->local, 0, sizeof(parser->local));
 863
 864         return 0;
 865 }
 866
 867 /*
 868  * Scan a report descriptor before the device is added to the bus.
 869  * Sets device groups and other properties that determine what driver
 870  * to load.
 871  */
 872 static int hid_scan_report(struct hid_device *hid)
 873 {
 874         struct hid_parser *parser;
 875         struct hid_item item;
 876         __u8 *start = hid->dev_rdesc;
 877         __u8 *end = start + hid->dev_rsize;
 878         static int (*dispatch_type[])(struct hid_parser *parser,
 879                                       struct hid_item *item) = {
 880                 hid_scan_main,
 881                 hid_parser_global,
 882                 hid_parser_local,
 883                 hid_parser_reserved
 884         };
 885
 886         parser = vzalloc(sizeof(struct hid_parser));
 887         if (!parser)
 888                 return -ENOMEM;
 889
 890         parser->device = hid;
 891         hid->group = HID_GROUP_GENERIC;
 892
 893         /*
 894          * The parsing is simpler than the one in hid_open_report() as we should
 895          * be robust against hid errors. Those errors will be raised by
 896          * hid_open_report() anyway.
 897          */
 898         while ((start = fetch_item(start, end, &item)) != NULL)
 899                 dispatch_type[item.type](parser, &item);
 900
 901         /*
 902          * Handle special flags set during scanning.
 903          */
 904         if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
 905             (hid->group == HID_GROUP_MULTITOUCH))
 906                 hid->group = HID_GROUP_MULTITOUCH_WIN_8;
 907
 908         /*
 909          * Vendor specific handlings
 910          */
 911         switch (hid->vendor) {
 912         case USB_VENDOR_ID_WACOM:
 913                 hid->group = HID_GROUP_WACOM;
 914                 break;
 915         case USB_VENDOR_ID_SYNAPTICS:
 916                 if (hid->group == HID_GROUP_GENERIC)
 917                         if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
 918                             && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
 919                                 /*
 920                                  * hid-rmi should take care of them,
 921                                  * not hid-generic
 922                                  */
 923                                 hid->group = HID_GROUP_RMI;
 924                 break;
 925         }
 926
 927         kfree(parser->collection_stack);
 928         vfree(parser);
 929         return 0;
 930 }
 931
 932 /**
 933  * hid_parse_report - parse device report
 934  *
 935  * @hid: hid device
 936  * @start: report start
 937  * @size: report size
 938  *
 939  * Allocate the device report as read by the bus driver. This function should
 940  * only be called from parse() in ll drivers.
 941  */
 942 int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
 943 {
 944         hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
 945         if (!hid->dev_rdesc)
 946                 return -ENOMEM;
 947         hid->dev_rsize = size;
 948         return 0;
 949 }
 950 EXPORT_SYMBOL_GPL(hid_parse_report);
 951
 952 static const char * const hid_report_names[] = {
 953         "HID_INPUT_REPORT",
 954         "HID_OUTPUT_REPORT",
 955         "HID_FEATURE_REPORT",
 956 };
 957 /**
 958  * hid_validate_values - validate existing device report's value indexes
 959  *
 960  * @hid: hid device
 961  * @type: which report type to examine
 962  * @id: which report ID to examine (0 for first)
 963  * @field_index: which report field to examine
 964  * @report_counts: expected number of values
 965  *
 966  * Validate the number of values in a given field of a given report, after
 967  * parsing.
 968  */
 969 struct hid_report *hid_validate_values(struct hid_device *hid,
 970                                        enum hid_report_type type, unsigned int id,
 971                                        unsigned int field_index,
 972                                        unsigned int report_counts)
 973 {
 974         struct hid_report *report;
 975
 976         if (type > HID_FEATURE_REPORT) {
 977                 hid_err(hid, "invalid HID report type %u\n", type);
 978                 return NULL;
 979         }
 980
 981         if (id >= HID_MAX_IDS) {
 982                 hid_err(hid, "invalid HID report id %u\n", id);
 983                 return NULL;
 984         }
 985
 986         /*
 987          * Explicitly not using hid_get_report() here since it depends on
 988          * ->numbered being checked, which may not always be the case when
 989          * drivers go to access report values.
 990          */
 991         if (id == 0) {
 992                 /*
 993                  * Validating on id 0 means we should examine the first
 994                  * report in the list.
 995                  */
 996                 report = list_first_entry_or_null(
 997                                 &hid->report_enum[type].report_list,
 998                                 struct hid_report, list);
 999         } else {
1000                 report = hid->report_enum[type].report_id_hash[id];
1001         }
1002         if (!report) {
1003                 hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
1004                 return NULL;
1005         }
1006         if (report->maxfield <= field_index) {
1007                 hid_err(hid, "not enough fields in %s %u\n",
1008                         hid_report_names[type], id);
1009                 return NULL;
1010         }
1011         if (report->field[field_index]->report_count < report_counts) {
1012                 hid_err(hid, "not enough values in %s %u field %u\n",
1013                         hid_report_names[type], id, field_index);
1014                 return NULL;
1015         }
1016         return report;
1017 }
1018 EXPORT_SYMBOL_GPL(hid_validate_values);
1019
1020 static int hid_calculate_multiplier(struct hid_device *hid,
1021                                      struct hid_field *multiplier)
1022 {
1023         int m;
1024         __s32 v = *multiplier->value;
1025         __s32 lmin = multiplier->logical_minimum;
1026         __s32 lmax = multiplier->logical_maximum;
1027         __s32 pmin = multiplier->physical_minimum;
1028         __s32 pmax = multiplier->physical_maximum;
1029
1030         /*
1031          * "Because OS implementations will generally divide the control's
1032          * reported count by the Effective Resolution Multiplier, designers
1033          * should take care not to establish a potential Effective
1034          * Resolution Multiplier of zero."
1035          * HID Usage Table, v1.12, Section 4.3.1, p31
1036          */
1037         if (lmax - lmin == 0)
1038                 return 1;
1039         /*
1040          * Handling the unit exponent is left as an exercise to whoever
1041          * finds a device where that exponent is not 0.
1042          */
1043         m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
1044         if (unlikely(multiplier->unit_exponent != 0)) {
1045                 hid_warn(hid,
1046                          "unsupported Resolution Multiplier unit exponent %d\n",
1047                          multiplier->unit_exponent);
1048         }
1049
1050         /* There are no devices with an effective multiplier > 255 */
1051         if (unlikely(m == 0 || m > 255 || m < -255)) {
1052                 hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
1053                 m = 1;
1054         }
1055
1056         return m;
1057 }
1058
1059 static void hid_apply_multiplier_to_field(struct hid_device *hid,
1060                                           struct hid_field *field,
1061                                           struct hid_collection *multiplier_collection,
1062                                           int effective_multiplier)
1063 {
1064         struct hid_collection *collection;
1065         struct hid_usage *usage;
1066         int i;
1067
1068         /*
1069          * If multiplier_collection is NULL, the multiplier applies
1070          * to all fields in the report.
1071          * Otherwise, it is the Logical Collection the multiplier applies to
1072          * but our field may be in a subcollection of that collection.
1073          */
1074         for (i = 0; i < field->maxusage; i++) {
1075                 usage = &field->usage[i];
1076
1077                 collection = &hid->collection[usage->collection_index];
1078                 while (collection->parent_idx != -1 &&
1079                        collection != multiplier_collection)
1080                         collection = &hid->collection[collection->parent_idx];
1081
1082                 if (collection->parent_idx != -1 ||
1083                     multiplier_collection == NULL)
1084                         usage->resolution_multiplier = effective_multiplier;
1085
1086         }
1087 }
1088
1089 static void hid_apply_multiplier(struct hid_device *hid,
1090                                  struct hid_field *multiplier)
1091 {
1092         struct hid_report_enum *rep_enum;
1093         struct hid_report *rep;
1094         struct hid_field *field;
1095         struct hid_collection *multiplier_collection;
1096         int effective_multiplier;
1097         int i;
1098
1099         /*
1100          * "The Resolution Multiplier control must be contained in the same
1101          * Logical Collection as the control(s) to which it is to be applied.
1102          * If no Resolution Multiplier is defined, then the Resolution
1103          * Multiplier defaults to 1.  If more than one control exists in a
1104          * Logical Collection, the Resolution Multiplier is associated with
1105          * all controls in the collection. If no Logical Collection is
1106          * defined, the Resolution Multiplier is associated with all
1107          * controls in the report."
1108          * HID Usage Table, v1.12, Section 4.3.1, p30
1109          *
1110          * Thus, search from the current collection upwards until we find a
1111          * logical collection. Then search all fields for that same parent
1112          * collection. Those are the fields the multiplier applies to.
1113          *
1114          * If we have more than one multiplier, it will overwrite the
1115          * applicable fields later.
1116          */
1117         multiplier_collection = &hid->collection[multiplier->usage->collection_index];
1118         while (multiplier_collection->parent_idx != -1 &&
1119                multiplier_collection->type != HID_COLLECTION_LOGICAL)
1120                 multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
1121
1122         effective_multiplier = hid_calculate_multiplier(hid, multiplier);
1123
1124         rep_enum = &hid->report_enum[HID_INPUT_REPORT];
1125         list_for_each_entry(rep, &rep_enum->report_list, list) {
1126                 for (i = 0; i < rep->maxfield; i++) {
1127                         field = rep->field[i];
1128                         hid_apply_multiplier_to_field(hid, field,
1129                                                       multiplier_collection,
1130                                                       effective_multiplier);
1131                 }
1132         }
1133 }
1134
1135 /*
1136  * hid_setup_resolution_multiplier - set up all resolution multipliers
1137  *
1138  * @device: hid device
1139  *
1140  * Search for all Resolution Multiplier Feature Reports and apply their
1141  * value to all matching Input items. This only updates the internal struct
1142  * fields.
1143  *
1144  * The Resolution Multiplier is applied by the hardware. If the multiplier
1145  * is anything other than 1, the hardware will send pre-multiplied events
1146  * so that the same physical interaction generates an accumulated
1147  *      accumulated_value = value * * multiplier
1148  * This may be achieved by sending
1149  * - "value * multiplier" for each event, or
1150  * - "value" but "multiplier" times as frequently, or
1151  * - a combination of the above
1152  * The only guarantee is that the same physical interaction always generates
1153  * an accumulated 'value * multiplier'.
1154  *
1155  * This function must be called before any event processing and after
1156  * any SetRequest to the Resolution Multiplier.
1157  */
1158 void hid_setup_resolution_multiplier(struct hid_device *hid)
1159 {
1160         struct hid_report_enum *rep_enum;
1161         struct hid_report *rep;
1162         struct hid_usage *usage;
1163         int i, j;
1164
1165         rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
1166         list_for_each_entry(rep, &rep_enum->report_list, list) {
1167                 for (i = 0; i < rep->maxfield; i++) {
1168                         /* Ignore if report count is out of bounds. */
1169                         if (rep->field[i]->report_count < 1)
1170                                 continue;
1171
1172                         for (j = 0; j < rep->field[i]->maxusage; j++) {
1173                                 usage = &rep->field[i]->usage[j];
1174                                 if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
1175                                         hid_apply_multiplier(hid,
1176                                                              rep->field[i]);
1177                         }
1178                 }
1179         }
1180 }
1181 EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
1182
1183 /**
1184  * hid_open_report - open a driver-specific device report
1185  *
1186  * @device: hid device
1187  *
1188  * Parse a report description into a hid_device structure. Reports are
1189  * enumerated, fields are attached to these reports.
1190  * 0 returned on success, otherwise nonzero error value.
1191  *
1192  * This function (or the equivalent hid_parse() macro) should only be
1193  * called from probe() in drivers, before starting the device.
1194  */
1195 int hid_open_report(struct hid_device *device)
1196 {
1197         struct hid_parser *parser;
1198         struct hid_item item;
1199         unsigned int size;
1200         __u8 *start;
1201         __u8 *buf;
1202         __u8 *end;
1203         __u8 *next;
1204         int ret;
1205         static int (*dispatch_type[])(struct hid_parser *parser,
1206                                       struct hid_item *item) = {
1207                 hid_parser_main,
1208                 hid_parser_global,
1209                 hid_parser_local,
1210                 hid_parser_reserved
1211         };
1212
1213         if (WARN_ON(device->status & HID_STAT_PARSED))
1214                 return -EBUSY;
1215
1216         start = device->dev_rdesc;
1217         if (WARN_ON(!start))
1218                 return -ENODEV;
1219         size = device->dev_rsize;
1220
1221         buf = kmemdup(start, size, GFP_KERNEL);
1222         if (buf == NULL)
1223                 return -ENOMEM;
1224
1225         if (device->driver->report_fixup)
1226                 start = device->driver->report_fixup(device, buf, &size);
1227         else
1228                 start = buf;
1229
1230         start = kmemdup(start, size, GFP_KERNEL);
1231         kfree(buf);
1232         if (start == NULL)
1233                 return -ENOMEM;
1234
1235         device->rdesc = start;
1236         device->rsize = size;
1237
1238         parser = vzalloc(sizeof(struct hid_parser));
1239         if (!parser) {
1240                 ret = -ENOMEM;
1241                 goto alloc_err;
1242         }
1243
1244         parser->device = device;
1245
1246         end = start + size;
1247
1248         device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
1249                                      sizeof(struct hid_collection), GFP_KERNEL);
1250         if (!device->collection) {
1251                 ret = -ENOMEM;
1252                 goto err;
1253         }
1254         device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
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         if (!size) {
2047                 dbg_hid("empty report\n");
2048                 ret = -1;
2049                 goto unlock;
2050         }
2051
2052         /* Avoid unnecessary overhead if debugfs is disabled */
2053         if (!list_empty(&hid->debug_list))
2054                 hid_dump_report(hid, type, data, size);
2055
2056         report = hid_get_report(report_enum, data);
2057
2058         if (!report) {
2059                 ret = -1;
2060                 goto unlock;
2061         }
2062
2063         if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
2064                 ret = hdrv->raw_event(hid, report, data, size);
2065                 if (ret < 0)
2066                         goto unlock;
2067         }
2068
2069         ret = hid_report_raw_event(hid, type, data, size, interrupt);
2070
2071 unlock:
2072         up(&hid->driver_input_lock);
2073         return ret;
2074 }
2075 EXPORT_SYMBOL_GPL(hid_input_report);
2076
2077 bool hid_match_one_id(const struct hid_device *hdev,
2078                       const struct hid_device_id *id)
2079 {
2080         return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
2081                 (id->group == HID_GROUP_ANY || id->group == hdev->group) &&
2082                 (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
2083                 (id->product == HID_ANY_ID || id->product == hdev->product);
2084 }
2085
2086 const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
2087                 const struct hid_device_id *id)
2088 {
2089         for (; id->bus; id++)
2090                 if (hid_match_one_id(hdev, id))
2091                         return id;
2092
2093         return NULL;
2094 }
2095 EXPORT_SYMBOL_GPL(hid_match_id);
2096
2097 static const struct hid_device_id hid_hiddev_list[] = {
2098         { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
2099         { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
2100         { }
2101 };
2102
2103 static bool hid_hiddev(struct hid_device *hdev)
2104 {
2105         return !!hid_match_id(hdev, hid_hiddev_list);
2106 }
2107
2108
2109 static ssize_t
2110 read_report_descriptor(struct file *filp, struct kobject *kobj,
2111                 struct bin_attribute *attr,
2112                 char *buf, loff_t off, size_t count)
2113 {
2114         struct device *dev = kobj_to_dev(kobj);
2115         struct hid_device *hdev = to_hid_device(dev);
2116
2117         if (off >= hdev->rsize)
2118                 return 0;
2119
2120         if (off + count > hdev->rsize)
2121                 count = hdev->rsize - off;
2122
2123         memcpy(buf, hdev->rdesc + off, count);
2124
2125         return count;
2126 }
2127
2128 static ssize_t
2129 show_country(struct device *dev, struct device_attribute *attr,
2130                 char *buf)
2131 {
2132         struct hid_device *hdev = to_hid_device(dev);
2133
2134         return sprintf(buf, "%02x\n", hdev->country & 0xff);
2135 }
2136
2137 static struct bin_attribute dev_bin_attr_report_desc = {
2138         .attr = { .name = "report_descriptor", .mode = 0444 },
2139         .read = read_report_descriptor,
2140         .size = HID_MAX_DESCRIPTOR_SIZE,
2141 };
2142
2143 static const struct device_attribute dev_attr_country = {
2144         .attr = { .name = "country", .mode = 0444 },
2145         .show = show_country,
2146 };
2147
2148 int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
2149 {
2150         static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
2151                 "Joystick", "Gamepad", "Keyboard", "Keypad",
2152                 "Multi-Axis Controller"
2153         };
2154         const char *type, *bus;
2155         char buf[64] = "";
2156         unsigned int i;
2157         int len;
2158         int ret;
2159
2160         if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
2161                 connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
2162         if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
2163                 connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
2164         if (hdev->bus != BUS_USB)
2165                 connect_mask &= ~HID_CONNECT_HIDDEV;
2166         if (hid_hiddev(hdev))
2167                 connect_mask |= HID_CONNECT_HIDDEV_FORCE;
2168
2169         if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
2170                                 connect_mask & HID_CONNECT_HIDINPUT_FORCE))
2171                 hdev->claimed |= HID_CLAIMED_INPUT;
2172
2173         if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
2174                         !hdev->hiddev_connect(hdev,
2175                                 connect_mask & HID_CONNECT_HIDDEV_FORCE))
2176                 hdev->claimed |= HID_CLAIMED_HIDDEV;
2177         if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
2178                 hdev->claimed |= HID_CLAIMED_HIDRAW;
2179
2180         if (connect_mask & HID_CONNECT_DRIVER)
2181                 hdev->claimed |= HID_CLAIMED_DRIVER;
2182
2183         /* Drivers with the ->raw_event callback set are not required to connect
2184          * to any other listener. */
2185         if (!hdev->claimed && !hdev->driver->raw_event) {
2186                 hid_err(hdev, "device has no listeners, quitting\n");
2187                 return -ENODEV;
2188         }
2189
2190         hid_process_ordering(hdev);
2191
2192         if ((hdev->claimed & HID_CLAIMED_INPUT) &&
2193                         (connect_mask & HID_CONNECT_FF) && hdev->ff_init)
2194                 hdev->ff_init(hdev);
2195
2196         len = 0;
2197         if (hdev->claimed & HID_CLAIMED_INPUT)
2198                 len += sprintf(buf + len, "input");
2199         if (hdev->claimed & HID_CLAIMED_HIDDEV)
2200                 len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
2201                                 ((struct hiddev *)hdev->hiddev)->minor);
2202         if (hdev->claimed & HID_CLAIMED_HIDRAW)
2203                 len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
2204                                 ((struct hidraw *)hdev->hidraw)->minor);
2205
2206         type = "Device";
2207         for (i = 0; i < hdev->maxcollection; i++) {
2208                 struct hid_collection *col = &hdev->collection[i];
2209                 if (col->type == HID_COLLECTION_APPLICATION &&
2210                    (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
2211                    (col->usage & 0xffff) < ARRAY_SIZE(types)) {
2212                         type = types[col->usage & 0xffff];
2213                         break;
2214                 }
2215         }
2216
2217         switch (hdev->bus) {
2218         case BUS_USB:
2219                 bus = "USB";
2220                 break;
2221         case BUS_BLUETOOTH:
2222                 bus = "BLUETOOTH";
2223                 break;
2224         case BUS_I2C:
2225                 bus = "I2C";
2226                 break;
2227         case BUS_VIRTUAL:
2228                 bus = "VIRTUAL";
2229                 break;
2230         case BUS_INTEL_ISHTP:
2231         case BUS_AMD_SFH:
2232                 bus = "SENSOR HUB";
2233                 break;
2234         default:
2235                 bus = "<UNKNOWN>";
2236         }
2237
2238         ret = device_create_file(&hdev->dev, &dev_attr_country);
2239         if (ret)
2240                 hid_warn(hdev,
2241                          "can't create sysfs country code attribute err: %d\n", ret);
2242
2243         hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
2244                  buf, bus, hdev->version >> 8, hdev->version & 0xff,
2245                  type, hdev->name, hdev->phys);
2246
2247         return 0;
2248 }
2249 EXPORT_SYMBOL_GPL(hid_connect);
2250
2251 void hid_disconnect(struct hid_device *hdev)
2252 {
2253         device_remove_file(&hdev->dev, &dev_attr_country);
2254         if (hdev->claimed & HID_CLAIMED_INPUT)
2255                 hidinput_disconnect(hdev);
2256         if (hdev->claimed & HID_CLAIMED_HIDDEV)
2257                 hdev->hiddev_disconnect(hdev);
2258         if (hdev->claimed & HID_CLAIMED_HIDRAW)
2259                 hidraw_disconnect(hdev);
2260         hdev->claimed = 0;
2261 }
2262 EXPORT_SYMBOL_GPL(hid_disconnect);
2263
2264 /**
2265  * hid_hw_start - start underlying HW
2266  * @hdev: hid device
2267  * @connect_mask: which outputs to connect, see HID_CONNECT_*
2268  *
2269  * Call this in probe function *after* hid_parse. This will setup HW
2270  * buffers and start the device (if not defeirred to device open).
2271  * hid_hw_stop must be called if this was successful.
2272  */
2273 int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
2274 {
2275         int error;
2276
2277         error = hdev->ll_driver->start(hdev);
2278         if (error)
2279                 return error;
2280
2281         if (connect_mask) {
2282                 error = hid_connect(hdev, connect_mask);
2283                 if (error) {
2284                         hdev->ll_driver->stop(hdev);
2285                         return error;
2286                 }
2287         }
2288
2289         return 0;
2290 }
2291 EXPORT_SYMBOL_GPL(hid_hw_start);
2292
2293 /**
2294  * hid_hw_stop - stop underlying HW
2295  * @hdev: hid device
2296  *
2297  * This is usually called from remove function or from probe when something
2298  * failed and hid_hw_start was called already.
2299  */
2300 void hid_hw_stop(struct hid_device *hdev)
2301 {
2302         hid_disconnect(hdev);
2303         hdev->ll_driver->stop(hdev);
2304 }
2305 EXPORT_SYMBOL_GPL(hid_hw_stop);
2306
2307 /**
2308  * hid_hw_open - signal underlying HW to start delivering events
2309  * @hdev: hid device
2310  *
2311  * Tell underlying HW to start delivering events from the device.
2312  * This function should be called sometime after successful call
2313  * to hid_hw_start().
2314  */
2315 int hid_hw_open(struct hid_device *hdev)
2316 {
2317         int ret;
2318
2319         ret = mutex_lock_killable(&hdev->ll_open_lock);
2320         if (ret)
2321                 return ret;
2322
2323         if (!hdev->ll_open_count++) {
2324                 ret = hdev->ll_driver->open(hdev);
2325                 if (ret)
2326                         hdev->ll_open_count--;
2327         }
2328
2329         mutex_unlock(&hdev->ll_open_lock);
2330         return ret;
2331 }
2332 EXPORT_SYMBOL_GPL(hid_hw_open);
2333
2334 /**
2335  * hid_hw_close - signal underlaying HW to stop delivering events
2336  *
2337  * @hdev: hid device
2338  *
2339  * This function indicates that we are not interested in the events
2340  * from this device anymore. Delivery of events may or may not stop,
2341  * depending on the number of users still outstanding.
2342  */
2343 void hid_hw_close(struct hid_device *hdev)
2344 {
2345         mutex_lock(&hdev->ll_open_lock);
2346         if (!--hdev->ll_open_count)
2347                 hdev->ll_driver->close(hdev);
2348         mutex_unlock(&hdev->ll_open_lock);
2349 }
2350 EXPORT_SYMBOL_GPL(hid_hw_close);
2351
2352 /**
2353  * hid_hw_request - send report request to device
2354  *
2355  * @hdev: hid device
2356  * @report: report to send
2357  * @reqtype: hid request type
2358  */
2359 void hid_hw_request(struct hid_device *hdev,
2360                     struct hid_report *report, enum hid_class_request reqtype)
2361 {
2362         if (hdev->ll_driver->request)
2363                 return hdev->ll_driver->request(hdev, report, reqtype);
2364
2365         __hid_request(hdev, report, reqtype);
2366 }
2367 EXPORT_SYMBOL_GPL(hid_hw_request);
2368
2369 /**
2370  * hid_hw_raw_request - send report request to device
2371  *
2372  * @hdev: hid device
2373  * @reportnum: report ID
2374  * @buf: in/out data to transfer
2375  * @len: length of buf
2376  * @rtype: HID report type
2377  * @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT
2378  *
2379  * Return: count of data transferred, negative if error
2380  *
2381  * Same behavior as hid_hw_request, but with raw buffers instead.
2382  */
2383 int hid_hw_raw_request(struct hid_device *hdev,
2384                        unsigned char reportnum, __u8 *buf,
2385                        size_t len, enum hid_report_type rtype, enum hid_class_request reqtype)
2386 {
2387         if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
2388                 return -EINVAL;
2389
2390         return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
2391                                             rtype, reqtype);
2392 }
2393 EXPORT_SYMBOL_GPL(hid_hw_raw_request);
2394
2395 /**
2396  * hid_hw_output_report - send output report to device
2397  *
2398  * @hdev: hid device
2399  * @buf: raw data to transfer
2400  * @len: length of buf
2401  *
2402  * Return: count of data transferred, negative if error
2403  */
2404 int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
2405 {
2406         if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
2407                 return -EINVAL;
2408
2409         if (hdev->ll_driver->output_report)
2410                 return hdev->ll_driver->output_report(hdev, buf, len);
2411
2412         return -ENOSYS;
2413 }
2414 EXPORT_SYMBOL_GPL(hid_hw_output_report);
2415
2416 #ifdef CONFIG_PM
2417 int hid_driver_suspend(struct hid_device *hdev, pm_message_t state)
2418 {
2419         if (hdev->driver && hdev->driver->suspend)
2420                 return hdev->driver->suspend(hdev, state);
2421
2422         return 0;
2423 }
2424 EXPORT_SYMBOL_GPL(hid_driver_suspend);
2425
2426 int hid_driver_reset_resume(struct hid_device *hdev)
2427 {
2428         if (hdev->driver && hdev->driver->reset_resume)
2429                 return hdev->driver->reset_resume(hdev);
2430
2431         return 0;
2432 }
2433 EXPORT_SYMBOL_GPL(hid_driver_reset_resume);
2434
2435 int hid_driver_resume(struct hid_device *hdev)
2436 {
2437         if (hdev->driver && hdev->driver->resume)
2438                 return hdev->driver->resume(hdev);
2439
2440         return 0;
2441 }
2442 EXPORT_SYMBOL_GPL(hid_driver_resume);
2443 #endif /* CONFIG_PM */
2444
2445 struct hid_dynid {
2446         struct list_head list;
2447         struct hid_device_id id;
2448 };
2449
2450 /**
2451  * new_id_store - add a new HID device ID to this driver and re-probe devices
2452  * @drv: target device driver
2453  * @buf: buffer for scanning device ID data
2454  * @count: input size
2455  *
2456  * Adds a new dynamic hid device ID to this driver,
2457  * and causes the driver to probe for all devices again.
2458  */
2459 static ssize_t new_id_store(struct device_driver *drv, const char *buf,
2460                 size_t count)
2461 {
2462         struct hid_driver *hdrv = to_hid_driver(drv);
2463         struct hid_dynid *dynid;
2464         __u32 bus, vendor, product;
2465         unsigned long driver_data = 0;
2466         int ret;
2467
2468         ret = sscanf(buf, "%x %x %x %lx",
2469                         &bus, &vendor, &product, &driver_data);
2470         if (ret < 3)
2471                 return -EINVAL;
2472
2473         dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
2474         if (!dynid)
2475                 return -ENOMEM;
2476
2477         dynid->id.bus = bus;
2478         dynid->id.group = HID_GROUP_ANY;
2479         dynid->id.vendor = vendor;
2480         dynid->id.product = product;
2481         dynid->id.driver_data = driver_data;
2482
2483         spin_lock(&hdrv->dyn_lock);
2484         list_add_tail(&dynid->list, &hdrv->dyn_list);
2485         spin_unlock(&hdrv->dyn_lock);
2486
2487         ret = driver_attach(&hdrv->driver);
2488
2489         return ret ? : count;
2490 }
2491 static DRIVER_ATTR_WO(new_id);
2492
2493 static struct attribute *hid_drv_attrs[] = {
2494         &driver_attr_new_id.attr,
2495         NULL,
2496 };
2497 ATTRIBUTE_GROUPS(hid_drv);
2498
2499 static void hid_free_dynids(struct hid_driver *hdrv)
2500 {
2501         struct hid_dynid *dynid, *n;
2502
2503         spin_lock(&hdrv->dyn_lock);
2504         list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
2505                 list_del(&dynid->list);
2506                 kfree(dynid);
2507         }
2508         spin_unlock(&hdrv->dyn_lock);
2509 }
2510
2511 const struct hid_device_id *hid_match_device(struct hid_device *hdev,
2512                                              struct hid_driver *hdrv)
2513 {
2514         struct hid_dynid *dynid;
2515
2516         spin_lock(&hdrv->dyn_lock);
2517         list_for_each_entry(dynid, &hdrv->dyn_list, list) {
2518                 if (hid_match_one_id(hdev, &dynid->id)) {
2519                         spin_unlock(&hdrv->dyn_lock);
2520                         return &dynid->id;
2521                 }
2522         }
2523         spin_unlock(&hdrv->dyn_lock);
2524
2525         return hid_match_id(hdev, hdrv->id_table);
2526 }
2527 EXPORT_SYMBOL_GPL(hid_match_device);
2528
2529 static int hid_bus_match(struct device *dev, struct device_driver *drv)
2530 {
2531         struct hid_driver *hdrv = to_hid_driver(drv);
2532         struct hid_device *hdev = to_hid_device(dev);
2533
2534         return hid_match_device(hdev, hdrv) != NULL;
2535 }
2536
2537 /**
2538  * hid_compare_device_paths - check if both devices share the same path
2539  * @hdev_a: hid device
2540  * @hdev_b: hid device
2541  * @separator: char to use as separator
2542  *
2543  * Check if two devices share the same path up to the last occurrence of
2544  * the separator char. Both paths must exist (i.e., zero-length paths
2545  * don't match).
2546  */
2547 bool hid_compare_device_paths(struct hid_device *hdev_a,
2548                               struct hid_device *hdev_b, char separator)
2549 {
2550         int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
2551         int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
2552
2553         if (n1 != n2 || n1 <= 0 || n2 <= 0)
2554                 return false;
2555
2556         return !strncmp(hdev_a->phys, hdev_b->phys, n1);
2557 }
2558 EXPORT_SYMBOL_GPL(hid_compare_device_paths);
2559
2560 static int hid_device_probe(struct device *dev)
2561 {
2562         struct hid_driver *hdrv = to_hid_driver(dev->driver);
2563         struct hid_device *hdev = to_hid_device(dev);
2564         const struct hid_device_id *id;
2565         int ret = 0;
2566
2567         if (down_interruptible(&hdev->driver_input_lock)) {
2568                 ret = -EINTR;
2569                 goto end;
2570         }
2571         hdev->io_started = false;
2572
2573         clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
2574
2575         if (!hdev->driver) {
2576                 id = hid_match_device(hdev, hdrv);
2577                 if (id == NULL) {
2578                         ret = -ENODEV;
2579                         goto unlock;
2580                 }
2581
2582                 if (hdrv->match) {
2583                         if (!hdrv->match(hdev, hid_ignore_special_drivers)) {
2584                                 ret = -ENODEV;
2585                                 goto unlock;
2586                         }
2587                 } else {
2588                         /*
2589                          * hid-generic implements .match(), so if
2590                          * hid_ignore_special_drivers is set, we can safely
2591                          * return.
2592                          */
2593                         if (hid_ignore_special_drivers) {
2594                                 ret = -ENODEV;
2595                                 goto unlock;
2596                         }
2597                 }
2598
2599                 /* reset the quirks that has been previously set */
2600                 hdev->quirks = hid_lookup_quirk(hdev);
2601                 hdev->driver = hdrv;
2602                 if (hdrv->probe) {
2603                         ret = hdrv->probe(hdev, id);
2604                 } else { /* default probe */
2605                         ret = hid_open_report(hdev);
2606                         if (!ret)
2607                                 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
2608                 }
2609                 if (ret) {
2610                         hid_close_report(hdev);
2611                         hdev->driver = NULL;
2612                 }
2613         }
2614 unlock:
2615         if (!hdev->io_started)
2616                 up(&hdev->driver_input_lock);
2617 end:
2618         return ret;
2619 }
2620
2621 static void hid_device_remove(struct device *dev)
2622 {
2623         struct hid_device *hdev = to_hid_device(dev);
2624         struct hid_driver *hdrv;
2625
2626         down(&hdev->driver_input_lock);
2627         hdev->io_started = false;
2628
2629         hdrv = hdev->driver;
2630         if (hdrv) {
2631                 if (hdrv->remove)
2632                         hdrv->remove(hdev);
2633                 else /* default remove */
2634                         hid_hw_stop(hdev);
2635                 hid_close_report(hdev);
2636                 hdev->driver = NULL;
2637         }
2638
2639         if (!hdev->io_started)
2640                 up(&hdev->driver_input_lock);
2641 }
2642
2643 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
2644                              char *buf)
2645 {
2646         struct hid_device *hdev = container_of(dev, struct hid_device, dev);
2647
2648         return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n",
2649                          hdev->bus, hdev->group, hdev->vendor, hdev->product);
2650 }
2651 static DEVICE_ATTR_RO(modalias);
2652
2653 static struct attribute *hid_dev_attrs[] = {
2654         &dev_attr_modalias.attr,
2655         NULL,
2656 };
2657 static struct bin_attribute *hid_dev_bin_attrs[] = {
2658         &dev_bin_attr_report_desc,
2659         NULL
2660 };
2661 static const struct attribute_group hid_dev_group = {
2662         .attrs = hid_dev_attrs,
2663         .bin_attrs = hid_dev_bin_attrs,
2664 };
2665 __ATTRIBUTE_GROUPS(hid_dev);
2666
2667 static int hid_uevent(struct device *dev, struct kobj_uevent_env *env)
2668 {
2669         struct hid_device *hdev = to_hid_device(dev);
2670
2671         if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
2672                         hdev->bus, hdev->vendor, hdev->product))
2673                 return -ENOMEM;
2674
2675         if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
2676                 return -ENOMEM;
2677
2678         if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
2679                 return -ENOMEM;
2680
2681         if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
2682                 return -ENOMEM;
2683
2684         if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
2685                            hdev->bus, hdev->group, hdev->vendor, hdev->product))
2686                 return -ENOMEM;
2687
2688         return 0;
2689 }
2690
2691 struct bus_type hid_bus_type = {
2692         .name           = "hid",
2693         .dev_groups     = hid_dev_groups,
2694         .drv_groups     = hid_drv_groups,
2695         .match          = hid_bus_match,
2696         .probe          = hid_device_probe,
2697         .remove         = hid_device_remove,
2698         .uevent         = hid_uevent,
2699 };
2700 EXPORT_SYMBOL(hid_bus_type);
2701
2702 int hid_add_device(struct hid_device *hdev)
2703 {
2704         static atomic_t id = ATOMIC_INIT(0);
2705         int ret;
2706
2707         if (WARN_ON(hdev->status & HID_STAT_ADDED))
2708                 return -EBUSY;
2709
2710         hdev->quirks = hid_lookup_quirk(hdev);
2711
2712         /* we need to kill them here, otherwise they will stay allocated to
2713          * wait for coming driver */
2714         if (hid_ignore(hdev))
2715                 return -ENODEV;
2716
2717         /*
2718          * Check for the mandatory transport channel.
2719          */
2720          if (!hdev->ll_driver->raw_request) {
2721                 hid_err(hdev, "transport driver missing .raw_request()\n");
2722                 return -EINVAL;
2723          }
2724
2725         /*
2726          * Read the device report descriptor once and use as template
2727          * for the driver-specific modifications.
2728          */
2729         ret = hdev->ll_driver->parse(hdev);
2730         if (ret)
2731                 return ret;
2732         if (!hdev->dev_rdesc)
2733                 return -ENODEV;
2734
2735         /*
2736          * Scan generic devices for group information
2737          */
2738         if (hid_ignore_special_drivers) {
2739                 hdev->group = HID_GROUP_GENERIC;
2740         } else if (!hdev->group &&
2741                    !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
2742                 ret = hid_scan_report(hdev);
2743                 if (ret)
2744                         hid_warn(hdev, "bad device descriptor (%d)\n", ret);
2745         }
2746
2747         hdev->id = atomic_inc_return(&id);
2748
2749         /* XXX hack, any other cleaner solution after the driver core
2750          * is converted to allow more than 20 bytes as the device name? */
2751         dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
2752                      hdev->vendor, hdev->product, hdev->id);
2753
2754         hid_debug_register(hdev, dev_name(&hdev->dev));
2755         ret = device_add(&hdev->dev);
2756         if (!ret)
2757                 hdev->status |= HID_STAT_ADDED;
2758         else
2759                 hid_debug_unregister(hdev);
2760
2761         return ret;
2762 }
2763 EXPORT_SYMBOL_GPL(hid_add_device);
2764
2765 /**
2766  * hid_allocate_device - allocate new hid device descriptor
2767  *
2768  * Allocate and initialize hid device, so that hid_destroy_device might be
2769  * used to free it.
2770  *
2771  * New hid_device pointer is returned on success, otherwise ERR_PTR encoded
2772  * error value.
2773  */
2774 struct hid_device *hid_allocate_device(void)
2775 {
2776         struct hid_device *hdev;
2777         int ret = -ENOMEM;
2778
2779         hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
2780         if (hdev == NULL)
2781                 return ERR_PTR(ret);
2782
2783         device_initialize(&hdev->dev);
2784         hdev->dev.release = hid_device_release;
2785         hdev->dev.bus = &hid_bus_type;
2786         device_enable_async_suspend(&hdev->dev);
2787
2788         hid_close_report(hdev);
2789
2790         init_waitqueue_head(&hdev->debug_wait);
2791         INIT_LIST_HEAD(&hdev->debug_list);
2792         spin_lock_init(&hdev->debug_list_lock);
2793         sema_init(&hdev->driver_input_lock, 1);
2794         mutex_init(&hdev->ll_open_lock);
2795
2796         return hdev;
2797 }
2798 EXPORT_SYMBOL_GPL(hid_allocate_device);
2799
2800 static void hid_remove_device(struct hid_device *hdev)
2801 {
2802         if (hdev->status & HID_STAT_ADDED) {
2803                 device_del(&hdev->dev);
2804                 hid_debug_unregister(hdev);
2805                 hdev->status &= ~HID_STAT_ADDED;
2806         }
2807         kfree(hdev->dev_rdesc);
2808         hdev->dev_rdesc = NULL;
2809         hdev->dev_rsize = 0;
2810 }
2811
2812 /**
2813  * hid_destroy_device - free previously allocated device
2814  *
2815  * @hdev: hid device
2816  *
2817  * If you allocate hid_device through hid_allocate_device, you should ever
2818  * free by this function.
2819  */
2820 void hid_destroy_device(struct hid_device *hdev)
2821 {
2822         hid_remove_device(hdev);
2823         put_device(&hdev->dev);
2824 }
2825 EXPORT_SYMBOL_GPL(hid_destroy_device);
2826
2827
2828 static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
2829 {
2830         struct hid_driver *hdrv = data;
2831         struct hid_device *hdev = to_hid_device(dev);
2832
2833         if (hdev->driver == hdrv &&
2834             !hdrv->match(hdev, hid_ignore_special_drivers) &&
2835             !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
2836                 return device_reprobe(dev);
2837
2838         return 0;
2839 }
2840
2841 static int __hid_bus_driver_added(struct device_driver *drv, void *data)
2842 {
2843         struct hid_driver *hdrv = to_hid_driver(drv);
2844
2845         if (hdrv->match) {
2846                 bus_for_each_dev(&hid_bus_type, NULL, hdrv,
2847                                  __hid_bus_reprobe_drivers);
2848         }
2849
2850         return 0;
2851 }
2852
2853 static int __bus_removed_driver(struct device_driver *drv, void *data)
2854 {
2855         return bus_rescan_devices(&hid_bus_type);
2856 }
2857
2858 int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
2859                 const char *mod_name)
2860 {
2861         int ret;
2862
2863         hdrv->driver.name = hdrv->name;
2864         hdrv->driver.bus = &hid_bus_type;
2865         hdrv->driver.owner = owner;
2866         hdrv->driver.mod_name = mod_name;
2867
2868         INIT_LIST_HEAD(&hdrv->dyn_list);
2869         spin_lock_init(&hdrv->dyn_lock);
2870
2871         ret = driver_register(&hdrv->driver);
2872
2873         if (ret == 0)
2874                 bus_for_each_drv(&hid_bus_type, NULL, NULL,
2875                                  __hid_bus_driver_added);
2876
2877         return ret;
2878 }
2879 EXPORT_SYMBOL_GPL(__hid_register_driver);
2880
2881 void hid_unregister_driver(struct hid_driver *hdrv)
2882 {
2883         driver_unregister(&hdrv->driver);
2884         hid_free_dynids(hdrv);
2885
2886         bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
2887 }
2888 EXPORT_SYMBOL_GPL(hid_unregister_driver);
2889
2890 int hid_check_keys_pressed(struct hid_device *hid)
2891 {
2892         struct hid_input *hidinput;
2893         int i;
2894
2895         if (!(hid->claimed & HID_CLAIMED_INPUT))
2896                 return 0;
2897
2898         list_for_each_entry(hidinput, &hid->inputs, list) {
2899                 for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
2900                         if (hidinput->input->key[i])
2901                                 return 1;
2902         }
2903
2904         return 0;
2905 }
2906 EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
2907
2908 static int __init hid_init(void)
2909 {
2910         int ret;
2911
2912         if (hid_debug)
2913                 pr_warn("hid_debug is now used solely for parser and driver debugging.\n"
2914                         "debugfs is now used for inspecting the device (report descriptor, reports)\n");
2915
2916         ret = bus_register(&hid_bus_type);
2917         if (ret) {
2918                 pr_err("can't register hid bus\n");
2919                 goto err;
2920         }
2921
2922         ret = hidraw_init();
2923         if (ret)
2924                 goto err_bus;
2925
2926         hid_debug_init();
2927
2928         return 0;
2929 err_bus:
2930         bus_unregister(&hid_bus_type);
2931 err:
2932         return ret;
2933 }
2934
2935 static void __exit hid_exit(void)
2936 {
2937         hid_debug_exit();
2938         hidraw_exit();
2939         bus_unregister(&hid_bus_type);
2940         hid_quirks_exit(HID_BUS_ANY);
2941 }
2942
2943 module_init(hid_init);
2944 module_exit(hid_exit);
2945
2946 MODULE_AUTHOR("Andreas Gal");
2947 MODULE_AUTHOR("Vojtech Pavlik");
2948 MODULE_AUTHOR("Jiri Kosina");
2949 MODULE_LICENSE("GPL");