drivers/hid/hid-core.c

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