hid-core.c revision d108d4fe34730135647fe32a4f8091491d3542ea
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 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#include <linux/module.h> 18#include <linux/slab.h> 19#include <linux/init.h> 20#include <linux/kernel.h> 21#include <linux/list.h> 22#include <linux/mm.h> 23#include <linux/smp_lock.h> 24#include <linux/spinlock.h> 25#include <asm/unaligned.h> 26#include <asm/byteorder.h> 27#include <linux/input.h> 28#include <linux/wait.h> 29#include <linux/vmalloc.h> 30 31#include <linux/hid.h> 32#include <linux/hiddev.h> 33#include <linux/hid-debug.h> 34 35/* 36 * Version Information 37 */ 38 39#define DRIVER_VERSION "v2.6" 40#define DRIVER_AUTHOR "Andreas Gal, Vojtech Pavlik" 41#define DRIVER_DESC "HID core driver" 42#define DRIVER_LICENSE "GPL" 43 44/* 45 * Register a new report for a device. 46 */ 47 48static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id) 49{ 50 struct hid_report_enum *report_enum = device->report_enum + type; 51 struct hid_report *report; 52 53 if (report_enum->report_id_hash[id]) 54 return report_enum->report_id_hash[id]; 55 56 if (!(report = kzalloc(sizeof(struct hid_report), GFP_KERNEL))) 57 return NULL; 58 59 if (id != 0) 60 report_enum->numbered = 1; 61 62 report->id = id; 63 report->type = type; 64 report->size = 0; 65 report->device = device; 66 report_enum->report_id_hash[id] = report; 67 68 list_add_tail(&report->list, &report_enum->report_list); 69 70 return report; 71} 72 73/* 74 * Register a new field for this report. 75 */ 76 77static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values) 78{ 79 struct hid_field *field; 80 81 if (report->maxfield == HID_MAX_FIELDS) { 82 dbg("too many fields in report"); 83 return NULL; 84 } 85 86 if (!(field = kzalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage) 87 + values * sizeof(unsigned), GFP_KERNEL))) return NULL; 88 89 field->index = report->maxfield++; 90 report->field[field->index] = field; 91 field->usage = (struct hid_usage *)(field + 1); 92 field->value = (unsigned *)(field->usage + usages); 93 field->report = report; 94 95 return field; 96} 97 98/* 99 * Open a collection. The type/usage is pushed on the stack. 100 */ 101 102static int open_collection(struct hid_parser *parser, unsigned type) 103{ 104 struct hid_collection *collection; 105 unsigned usage; 106 107 usage = parser->local.usage[0]; 108 109 if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) { 110 dbg("collection stack overflow"); 111 return -1; 112 } 113 114 if (parser->device->maxcollection == parser->device->collection_size) { 115 collection = kmalloc(sizeof(struct hid_collection) * 116 parser->device->collection_size * 2, GFP_KERNEL); 117 if (collection == NULL) { 118 dbg("failed to reallocate collection array"); 119 return -1; 120 } 121 memcpy(collection, parser->device->collection, 122 sizeof(struct hid_collection) * 123 parser->device->collection_size); 124 memset(collection + parser->device->collection_size, 0, 125 sizeof(struct hid_collection) * 126 parser->device->collection_size); 127 kfree(parser->device->collection); 128 parser->device->collection = collection; 129 parser->device->collection_size *= 2; 130 } 131 132 parser->collection_stack[parser->collection_stack_ptr++] = 133 parser->device->maxcollection; 134 135 collection = parser->device->collection + 136 parser->device->maxcollection++; 137 collection->type = type; 138 collection->usage = usage; 139 collection->level = parser->collection_stack_ptr - 1; 140 141 if (type == HID_COLLECTION_APPLICATION) 142 parser->device->maxapplication++; 143 144 return 0; 145} 146 147/* 148 * Close a collection. 149 */ 150 151static int close_collection(struct hid_parser *parser) 152{ 153 if (!parser->collection_stack_ptr) { 154 dbg("collection stack underflow"); 155 return -1; 156 } 157 parser->collection_stack_ptr--; 158 return 0; 159} 160 161/* 162 * Climb up the stack, search for the specified collection type 163 * and return the usage. 164 */ 165 166static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) 167{ 168 int n; 169 for (n = parser->collection_stack_ptr - 1; n >= 0; n--) 170 if (parser->device->collection[parser->collection_stack[n]].type == type) 171 return parser->device->collection[parser->collection_stack[n]].usage; 172 return 0; /* we know nothing about this usage type */ 173} 174 175/* 176 * Add a usage to the temporary parser table. 177 */ 178 179static int hid_add_usage(struct hid_parser *parser, unsigned usage) 180{ 181 if (parser->local.usage_index >= HID_MAX_USAGES) { 182 dbg("usage index exceeded"); 183 return -1; 184 } 185 parser->local.usage[parser->local.usage_index] = usage; 186 parser->local.collection_index[parser->local.usage_index] = 187 parser->collection_stack_ptr ? 188 parser->collection_stack[parser->collection_stack_ptr - 1] : 0; 189 parser->local.usage_index++; 190 return 0; 191} 192 193/* 194 * Register a new field for this report. 195 */ 196 197static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags) 198{ 199 struct hid_report *report; 200 struct hid_field *field; 201 int usages; 202 unsigned offset; 203 int i; 204 205 if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) { 206 dbg("hid_register_report failed"); 207 return -1; 208 } 209 210 if (parser->global.logical_maximum < parser->global.logical_minimum) { 211 dbg("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum); 212 return -1; 213 } 214 215 offset = report->size; 216 report->size += parser->global.report_size * parser->global.report_count; 217 218 if (!parser->local.usage_index) /* Ignore padding fields */ 219 return 0; 220 221 usages = max_t(int, parser->local.usage_index, parser->global.report_count); 222 223 if ((field = hid_register_field(report, usages, parser->global.report_count)) == NULL) 224 return 0; 225 226 field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL); 227 field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL); 228 field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); 229 230 for (i = 0; i < usages; i++) { 231 int j = i; 232 /* Duplicate the last usage we parsed if we have excess values */ 233 if (i >= parser->local.usage_index) 234 j = parser->local.usage_index - 1; 235 field->usage[i].hid = parser->local.usage[j]; 236 field->usage[i].collection_index = 237 parser->local.collection_index[j]; 238 } 239 240 field->maxusage = usages; 241 field->flags = flags; 242 field->report_offset = offset; 243 field->report_type = report_type; 244 field->report_size = parser->global.report_size; 245 field->report_count = parser->global.report_count; 246 field->logical_minimum = parser->global.logical_minimum; 247 field->logical_maximum = parser->global.logical_maximum; 248 field->physical_minimum = parser->global.physical_minimum; 249 field->physical_maximum = parser->global.physical_maximum; 250 field->unit_exponent = parser->global.unit_exponent; 251 field->unit = parser->global.unit; 252 253 return 0; 254} 255 256/* 257 * Read data value from item. 258 */ 259 260static u32 item_udata(struct hid_item *item) 261{ 262 switch (item->size) { 263 case 1: return item->data.u8; 264 case 2: return item->data.u16; 265 case 4: return item->data.u32; 266 } 267 return 0; 268} 269 270static s32 item_sdata(struct hid_item *item) 271{ 272 switch (item->size) { 273 case 1: return item->data.s8; 274 case 2: return item->data.s16; 275 case 4: return item->data.s32; 276 } 277 return 0; 278} 279 280/* 281 * Process a global item. 282 */ 283 284static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) 285{ 286 switch (item->tag) { 287 288 case HID_GLOBAL_ITEM_TAG_PUSH: 289 290 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) { 291 dbg("global enviroment stack overflow"); 292 return -1; 293 } 294 295 memcpy(parser->global_stack + parser->global_stack_ptr++, 296 &parser->global, sizeof(struct hid_global)); 297 return 0; 298 299 case HID_GLOBAL_ITEM_TAG_POP: 300 301 if (!parser->global_stack_ptr) { 302 dbg("global enviroment stack underflow"); 303 return -1; 304 } 305 306 memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr, 307 sizeof(struct hid_global)); 308 return 0; 309 310 case HID_GLOBAL_ITEM_TAG_USAGE_PAGE: 311 parser->global.usage_page = item_udata(item); 312 return 0; 313 314 case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM: 315 parser->global.logical_minimum = item_sdata(item); 316 return 0; 317 318 case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM: 319 if (parser->global.logical_minimum < 0) 320 parser->global.logical_maximum = item_sdata(item); 321 else 322 parser->global.logical_maximum = item_udata(item); 323 return 0; 324 325 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM: 326 parser->global.physical_minimum = item_sdata(item); 327 return 0; 328 329 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM: 330 if (parser->global.physical_minimum < 0) 331 parser->global.physical_maximum = item_sdata(item); 332 else 333 parser->global.physical_maximum = item_udata(item); 334 return 0; 335 336 case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: 337 parser->global.unit_exponent = item_sdata(item); 338 return 0; 339 340 case HID_GLOBAL_ITEM_TAG_UNIT: 341 parser->global.unit = item_udata(item); 342 return 0; 343 344 case HID_GLOBAL_ITEM_TAG_REPORT_SIZE: 345 if ((parser->global.report_size = item_udata(item)) > 32) { 346 dbg("invalid report_size %d", parser->global.report_size); 347 return -1; 348 } 349 return 0; 350 351 case HID_GLOBAL_ITEM_TAG_REPORT_COUNT: 352 if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) { 353 dbg("invalid report_count %d", parser->global.report_count); 354 return -1; 355 } 356 return 0; 357 358 case HID_GLOBAL_ITEM_TAG_REPORT_ID: 359 if ((parser->global.report_id = item_udata(item)) == 0) { 360 dbg("report_id 0 is invalid"); 361 return -1; 362 } 363 return 0; 364 365 default: 366 dbg("unknown global tag 0x%x", item->tag); 367 return -1; 368 } 369} 370 371/* 372 * Process a local item. 373 */ 374 375static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) 376{ 377 __u32 data; 378 unsigned n; 379 380 if (item->size == 0) { 381 dbg("item data expected for local item"); 382 return -1; 383 } 384 385 data = item_udata(item); 386 387 switch (item->tag) { 388 389 case HID_LOCAL_ITEM_TAG_DELIMITER: 390 391 if (data) { 392 /* 393 * We treat items before the first delimiter 394 * as global to all usage sets (branch 0). 395 * In the moment we process only these global 396 * items and the first delimiter set. 397 */ 398 if (parser->local.delimiter_depth != 0) { 399 dbg("nested delimiters"); 400 return -1; 401 } 402 parser->local.delimiter_depth++; 403 parser->local.delimiter_branch++; 404 } else { 405 if (parser->local.delimiter_depth < 1) { 406 dbg("bogus close delimiter"); 407 return -1; 408 } 409 parser->local.delimiter_depth--; 410 } 411 return 1; 412 413 case HID_LOCAL_ITEM_TAG_USAGE: 414 415 if (parser->local.delimiter_branch > 1) { 416 dbg("alternative usage ignored"); 417 return 0; 418 } 419 420 if (item->size <= 2) 421 data = (parser->global.usage_page << 16) + data; 422 423 return hid_add_usage(parser, data); 424 425 case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: 426 427 if (parser->local.delimiter_branch > 1) { 428 dbg("alternative usage ignored"); 429 return 0; 430 } 431 432 if (item->size <= 2) 433 data = (parser->global.usage_page << 16) + data; 434 435 parser->local.usage_minimum = data; 436 return 0; 437 438 case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: 439 440 if (parser->local.delimiter_branch > 1) { 441 dbg("alternative usage ignored"); 442 return 0; 443 } 444 445 if (item->size <= 2) 446 data = (parser->global.usage_page << 16) + data; 447 448 for (n = parser->local.usage_minimum; n <= data; n++) 449 if (hid_add_usage(parser, n)) { 450 dbg("hid_add_usage failed\n"); 451 return -1; 452 } 453 return 0; 454 455 default: 456 457 dbg("unknown local item tag 0x%x", item->tag); 458 return 0; 459 } 460 return 0; 461} 462 463/* 464 * Process a main item. 465 */ 466 467static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) 468{ 469 __u32 data; 470 int ret; 471 472 data = item_udata(item); 473 474 switch (item->tag) { 475 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: 476 ret = open_collection(parser, data & 0xff); 477 break; 478 case HID_MAIN_ITEM_TAG_END_COLLECTION: 479 ret = close_collection(parser); 480 break; 481 case HID_MAIN_ITEM_TAG_INPUT: 482 ret = hid_add_field(parser, HID_INPUT_REPORT, data); 483 break; 484 case HID_MAIN_ITEM_TAG_OUTPUT: 485 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data); 486 break; 487 case HID_MAIN_ITEM_TAG_FEATURE: 488 ret = hid_add_field(parser, HID_FEATURE_REPORT, data); 489 break; 490 default: 491 dbg("unknown main item tag 0x%x", item->tag); 492 ret = 0; 493 } 494 495 memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */ 496 497 return ret; 498} 499 500/* 501 * Process a reserved item. 502 */ 503 504static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item) 505{ 506 dbg("reserved item type, tag 0x%x", item->tag); 507 return 0; 508} 509 510/* 511 * Free a report and all registered fields. The field->usage and 512 * field->value table's are allocated behind the field, so we need 513 * only to free(field) itself. 514 */ 515 516static void hid_free_report(struct hid_report *report) 517{ 518 unsigned n; 519 520 for (n = 0; n < report->maxfield; n++) 521 kfree(report->field[n]); 522 kfree(report); 523} 524 525/* 526 * Free a device structure, all reports, and all fields. 527 */ 528 529void hid_free_device(struct hid_device *device) 530{ 531 unsigned i,j; 532 533 for (i = 0; i < HID_REPORT_TYPES; i++) { 534 struct hid_report_enum *report_enum = device->report_enum + i; 535 536 for (j = 0; j < 256; j++) { 537 struct hid_report *report = report_enum->report_id_hash[j]; 538 if (report) 539 hid_free_report(report); 540 } 541 } 542 543 kfree(device->rdesc); 544 kfree(device->collection); 545 kfree(device); 546} 547EXPORT_SYMBOL_GPL(hid_free_device); 548 549/* 550 * Fetch a report description item from the data stream. We support long 551 * items, though they are not used yet. 552 */ 553 554static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item) 555{ 556 u8 b; 557 558 if ((end - start) <= 0) 559 return NULL; 560 561 b = *start++; 562 563 item->type = (b >> 2) & 3; 564 item->tag = (b >> 4) & 15; 565 566 if (item->tag == HID_ITEM_TAG_LONG) { 567 568 item->format = HID_ITEM_FORMAT_LONG; 569 570 if ((end - start) < 2) 571 return NULL; 572 573 item->size = *start++; 574 item->tag = *start++; 575 576 if ((end - start) < item->size) 577 return NULL; 578 579 item->data.longdata = start; 580 start += item->size; 581 return start; 582 } 583 584 item->format = HID_ITEM_FORMAT_SHORT; 585 item->size = b & 3; 586 587 switch (item->size) { 588 589 case 0: 590 return start; 591 592 case 1: 593 if ((end - start) < 1) 594 return NULL; 595 item->data.u8 = *start++; 596 return start; 597 598 case 2: 599 if ((end - start) < 2) 600 return NULL; 601 item->data.u16 = le16_to_cpu(get_unaligned((__le16*)start)); 602 start = (__u8 *)((__le16 *)start + 1); 603 return start; 604 605 case 3: 606 item->size++; 607 if ((end - start) < 4) 608 return NULL; 609 item->data.u32 = le32_to_cpu(get_unaligned((__le32*)start)); 610 start = (__u8 *)((__le32 *)start + 1); 611 return start; 612 } 613 614 return NULL; 615} 616 617/* 618 * Parse a report description into a hid_device structure. Reports are 619 * enumerated, fields are attached to these reports. 620 */ 621 622struct hid_device *hid_parse_report(__u8 *start, unsigned size) 623{ 624 struct hid_device *device; 625 struct hid_parser *parser; 626 struct hid_item item; 627 __u8 *end; 628 unsigned i; 629 static int (*dispatch_type[])(struct hid_parser *parser, 630 struct hid_item *item) = { 631 hid_parser_main, 632 hid_parser_global, 633 hid_parser_local, 634 hid_parser_reserved 635 }; 636 637 if (!(device = kzalloc(sizeof(struct hid_device), GFP_KERNEL))) 638 return NULL; 639 640 if (!(device->collection = kzalloc(sizeof(struct hid_collection) * 641 HID_DEFAULT_NUM_COLLECTIONS, GFP_KERNEL))) { 642 kfree(device); 643 return NULL; 644 } 645 device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; 646 647 for (i = 0; i < HID_REPORT_TYPES; i++) 648 INIT_LIST_HEAD(&device->report_enum[i].report_list); 649 650 if (!(device->rdesc = kmalloc(size, GFP_KERNEL))) { 651 kfree(device->collection); 652 kfree(device); 653 return NULL; 654 } 655 memcpy(device->rdesc, start, size); 656 device->rsize = size; 657 658 if (!(parser = vmalloc(sizeof(struct hid_parser)))) { 659 kfree(device->rdesc); 660 kfree(device->collection); 661 kfree(device); 662 return NULL; 663 } 664 memset(parser, 0, sizeof(struct hid_parser)); 665 parser->device = device; 666 667 end = start + size; 668 while ((start = fetch_item(start, end, &item)) != NULL) { 669 670 if (item.format != HID_ITEM_FORMAT_SHORT) { 671 dbg("unexpected long global item"); 672 hid_free_device(device); 673 vfree(parser); 674 return NULL; 675 } 676 677 if (dispatch_type[item.type](parser, &item)) { 678 dbg("item %u %u %u %u parsing failed\n", 679 item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag); 680 hid_free_device(device); 681 vfree(parser); 682 return NULL; 683 } 684 685 if (start == end) { 686 if (parser->collection_stack_ptr) { 687 dbg("unbalanced collection at end of report description"); 688 hid_free_device(device); 689 vfree(parser); 690 return NULL; 691 } 692 if (parser->local.delimiter_depth) { 693 dbg("unbalanced delimiter at end of report description"); 694 hid_free_device(device); 695 vfree(parser); 696 return NULL; 697 } 698 vfree(parser); 699 return device; 700 } 701 } 702 703 dbg("item fetching failed at offset %d\n", (int)(end - start)); 704 hid_free_device(device); 705 vfree(parser); 706 return NULL; 707} 708EXPORT_SYMBOL_GPL(hid_parse_report); 709 710/* 711 * Convert a signed n-bit integer to signed 32-bit integer. Common 712 * cases are done through the compiler, the screwed things has to be 713 * done by hand. 714 */ 715 716static s32 snto32(__u32 value, unsigned n) 717{ 718 switch (n) { 719 case 8: return ((__s8)value); 720 case 16: return ((__s16)value); 721 case 32: return ((__s32)value); 722 } 723 return value & (1 << (n - 1)) ? value | (-1 << n) : value; 724} 725 726/* 727 * Convert a signed 32-bit integer to a signed n-bit integer. 728 */ 729 730static u32 s32ton(__s32 value, unsigned n) 731{ 732 s32 a = value >> (n - 1); 733 if (a && a != -1) 734 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; 735 return value & ((1 << n) - 1); 736} 737 738/* 739 * Extract/implement a data field from/to a little endian report (bit array). 740 * 741 * Code sort-of follows HID spec: 742 * http://www.usb.org/developers/devclass_docs/HID1_11.pdf 743 * 744 * While the USB HID spec allows unlimited length bit fields in "report 745 * descriptors", most devices never use more than 16 bits. 746 * One model of UPS is claimed to report "LINEV" as a 32-bit field. 747 * Search linux-kernel and linux-usb-devel archives for "hid-core extract". 748 */ 749 750static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n) 751{ 752 u64 x; 753 754 WARN_ON(n > 32); 755 756 report += offset >> 3; /* adjust byte index */ 757 offset &= 7; /* now only need bit offset into one byte */ 758 x = get_unaligned((u64 *) report); 759 x = le64_to_cpu(x); 760 x = (x >> offset) & ((1ULL << n) - 1); /* extract bit field */ 761 return (u32) x; 762} 763 764/* 765 * "implement" : set bits in a little endian bit stream. 766 * Same concepts as "extract" (see comments above). 767 * The data mangled in the bit stream remains in little endian 768 * order the whole time. It make more sense to talk about 769 * endianness of register values by considering a register 770 * a "cached" copy of the little endiad bit stream. 771 */ 772static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value) 773{ 774 u64 x; 775 u64 m = (1ULL << n) - 1; 776 777 WARN_ON(n > 32); 778 779 WARN_ON(value > m); 780 value &= m; 781 782 report += offset >> 3; 783 offset &= 7; 784 785 x = get_unaligned((u64 *)report); 786 x &= cpu_to_le64(~(m << offset)); 787 x |= cpu_to_le64(((u64) value) << offset); 788 put_unaligned(x, (u64 *) report); 789} 790 791/* 792 * Search an array for a value. 793 */ 794 795static __inline__ int search(__s32 *array, __s32 value, unsigned n) 796{ 797 while (n--) { 798 if (*array++ == value) 799 return 0; 800 } 801 return -1; 802} 803 804static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt) 805{ 806 hid_dump_input(usage, value); 807 if (hid->claimed & HID_CLAIMED_INPUT) 808 hidinput_hid_event(hid, field, usage, value); 809 if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) 810 hid->hiddev_hid_event(hid, field, usage, value); 811} 812 813/* 814 * Analyse a received field, and fetch the data from it. The field 815 * content is stored for next report processing (we do differential 816 * reporting to the layer). 817 */ 818 819void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt) 820{ 821 unsigned n; 822 unsigned count = field->report_count; 823 unsigned offset = field->report_offset; 824 unsigned size = field->report_size; 825 __s32 min = field->logical_minimum; 826 __s32 max = field->logical_maximum; 827 __s32 *value; 828 829 if (!(value = kmalloc(sizeof(__s32) * count, GFP_ATOMIC))) 830 return; 831 832 for (n = 0; n < count; n++) { 833 834 value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) : 835 extract(data, offset + n * size, size); 836 837 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) /* Ignore report if ErrorRollOver */ 838 && value[n] >= min && value[n] <= max 839 && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) 840 goto exit; 841 } 842 843 for (n = 0; n < count; n++) { 844 845 if (HID_MAIN_ITEM_VARIABLE & field->flags) { 846 hid_process_event(hid, field, &field->usage[n], value[n], interrupt); 847 continue; 848 } 849 850 if (field->value[n] >= min && field->value[n] <= max 851 && field->usage[field->value[n] - min].hid 852 && search(value, field->value[n], count)) 853 hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); 854 855 if (value[n] >= min && value[n] <= max 856 && field->usage[value[n] - min].hid 857 && search(field->value, value[n], count)) 858 hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); 859 } 860 861 memcpy(field->value, value, count * sizeof(__s32)); 862exit: 863 kfree(value); 864} 865EXPORT_SYMBOL_GPL(hid_input_field); 866 867/* 868 * Output the field into the report. 869 */ 870 871static void hid_output_field(struct hid_field *field, __u8 *data) 872{ 873 unsigned count = field->report_count; 874 unsigned offset = field->report_offset; 875 unsigned size = field->report_size; 876 unsigned n; 877 878 for (n = 0; n < count; n++) { 879 if (field->logical_minimum < 0) /* signed values */ 880 implement(data, offset + n * size, size, s32ton(field->value[n], size)); 881 else /* unsigned values */ 882 implement(data, offset + n * size, size, field->value[n]); 883 } 884} 885 886/* 887 * Create a report. 888 */ 889 890void hid_output_report(struct hid_report *report, __u8 *data) 891{ 892 unsigned n; 893 894 if (report->id > 0) 895 *data++ = report->id; 896 897 for (n = 0; n < report->maxfield; n++) 898 hid_output_field(report->field[n], data); 899} 900EXPORT_SYMBOL_GPL(hid_output_report); 901 902/* 903 * Set a field value. The report this field belongs to has to be 904 * created and transferred to the device, to set this value in the 905 * device. 906 */ 907 908int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) 909{ 910 unsigned size = field->report_size; 911 912 hid_dump_input(field->usage + offset, value); 913 914 if (offset >= field->report_count) { 915 dbg("offset (%d) exceeds report_count (%d)", offset, field->report_count); 916 hid_dump_field(field, 8); 917 return -1; 918 } 919 if (field->logical_minimum < 0) { 920 if (value != snto32(s32ton(value, size), size)) { 921 dbg("value %d is out of range", value); 922 return -1; 923 } 924 } 925 field->value[offset] = value; 926 return 0; 927} 928EXPORT_SYMBOL_GPL(hid_set_field); 929 930int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt) 931{ 932 struct hid_report_enum *report_enum = hid->report_enum + type; 933 struct hid_report *report; 934 int n, rsize; 935 936 if (!hid) 937 return -ENODEV; 938 939 if (!size) { 940 dbg("empty report"); 941 return -1; 942 } 943 944#ifdef CONFIG_HID_DEBUG 945 printk(KERN_DEBUG __FILE__ ": report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un"); 946#endif 947 948 n = 0; /* Normally report number is 0 */ 949 if (report_enum->numbered) { /* Device uses numbered reports, data[0] is report number */ 950 n = *data++; 951 size--; 952 } 953 954#ifdef CONFIG_HID_DEBUG 955 { 956 int i; 957 printk(KERN_DEBUG __FILE__ ": report %d (size %u) = ", n, size); 958 for (i = 0; i < size; i++) 959 printk(" %02x", data[i]); 960 printk("\n"); 961 } 962#endif 963 964 if (!(report = report_enum->report_id_hash[n])) { 965 dbg("undefined report_id %d received", n); 966 return -1; 967 } 968 969 rsize = ((report->size - 1) >> 3) + 1; 970 971 if (size < rsize) { 972 dbg("report %d is too short, (%d < %d)", report->id, size, rsize); 973 return -1; 974 } 975 976 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) 977 hid->hiddev_report_event(hid, report); 978 979 for (n = 0; n < report->maxfield; n++) 980 hid_input_field(hid, report->field[n], data, interrupt); 981 982 if (hid->claimed & HID_CLAIMED_INPUT) 983 hidinput_report_event(hid, report); 984 985 return 0; 986} 987EXPORT_SYMBOL_GPL(hid_input_report); 988 989MODULE_LICENSE(DRIVER_LICENSE); 990 991