drivers/hid/hid-core.c

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