hid-core.c revision 58037eb961f859607b161c50d9d4ecb374de1e8f
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) 2006-2007 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/spinlock.h> 24#include <asm/unaligned.h> 25#include <asm/byteorder.h> 26#include <linux/input.h> 27#include <linux/wait.h> 28#include <linux/vmalloc.h> 29 30#include <linux/hid.h> 31#include <linux/hiddev.h> 32#include <linux/hid-debug.h> 33 34/* 35 * Version Information 36 */ 37 38#define DRIVER_VERSION "v2.6" 39#define DRIVER_AUTHOR "Andreas Gal, Vojtech Pavlik, Jiri Kosina" 40#define DRIVER_DESC "HID core driver" 41#define DRIVER_LICENSE "GPL" 42 43#ifdef CONFIG_HID_DEBUG 44int hid_debug = 0; 45module_param_named(debug, hid_debug, bool, 0600); 46MODULE_PARM_DESC(debug, "Turn HID debugging mode on and off"); 47EXPORT_SYMBOL_GPL(hid_debug); 48#endif 49 50/* 51 * Register a new report for a device. 52 */ 53 54static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id) 55{ 56 struct hid_report_enum *report_enum = device->report_enum + type; 57 struct hid_report *report; 58 59 if (report_enum->report_id_hash[id]) 60 return report_enum->report_id_hash[id]; 61 62 if (!(report = kzalloc(sizeof(struct hid_report), GFP_KERNEL))) 63 return NULL; 64 65 if (id != 0) 66 report_enum->numbered = 1; 67 68 report->id = id; 69 report->type = type; 70 report->size = 0; 71 report->device = device; 72 report_enum->report_id_hash[id] = report; 73 74 list_add_tail(&report->list, &report_enum->report_list); 75 76 return report; 77} 78 79/* 80 * Register a new field for this report. 81 */ 82 83static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values) 84{ 85 struct hid_field *field; 86 87 if (report->maxfield == HID_MAX_FIELDS) { 88 dbg_hid("too many fields in report\n"); 89 return NULL; 90 } 91 92 if (!(field = kzalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage) 93 + values * sizeof(unsigned), GFP_KERNEL))) return NULL; 94 95 field->index = report->maxfield++; 96 report->field[field->index] = field; 97 field->usage = (struct hid_usage *)(field + 1); 98 field->value = (unsigned *)(field->usage + usages); 99 field->report = report; 100 101 return field; 102} 103 104/* 105 * Open a collection. The type/usage is pushed on the stack. 106 */ 107 108static int open_collection(struct hid_parser *parser, unsigned type) 109{ 110 struct hid_collection *collection; 111 unsigned usage; 112 113 usage = parser->local.usage[0]; 114 115 if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) { 116 dbg_hid("collection stack overflow\n"); 117 return -1; 118 } 119 120 if (parser->device->maxcollection == parser->device->collection_size) { 121 collection = kmalloc(sizeof(struct hid_collection) * 122 parser->device->collection_size * 2, GFP_KERNEL); 123 if (collection == NULL) { 124 dbg_hid("failed to reallocate collection array\n"); 125 return -1; 126 } 127 memcpy(collection, parser->device->collection, 128 sizeof(struct hid_collection) * 129 parser->device->collection_size); 130 memset(collection + parser->device->collection_size, 0, 131 sizeof(struct hid_collection) * 132 parser->device->collection_size); 133 kfree(parser->device->collection); 134 parser->device->collection = collection; 135 parser->device->collection_size *= 2; 136 } 137 138 parser->collection_stack[parser->collection_stack_ptr++] = 139 parser->device->maxcollection; 140 141 collection = parser->device->collection + 142 parser->device->maxcollection++; 143 collection->type = type; 144 collection->usage = usage; 145 collection->level = parser->collection_stack_ptr - 1; 146 147 if (type == HID_COLLECTION_APPLICATION) 148 parser->device->maxapplication++; 149 150 return 0; 151} 152 153/* 154 * Close a collection. 155 */ 156 157static int close_collection(struct hid_parser *parser) 158{ 159 if (!parser->collection_stack_ptr) { 160 dbg_hid("collection stack underflow\n"); 161 return -1; 162 } 163 parser->collection_stack_ptr--; 164 return 0; 165} 166 167/* 168 * Climb up the stack, search for the specified collection type 169 * and return the usage. 170 */ 171 172static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) 173{ 174 int n; 175 for (n = parser->collection_stack_ptr - 1; n >= 0; n--) 176 if (parser->device->collection[parser->collection_stack[n]].type == type) 177 return parser->device->collection[parser->collection_stack[n]].usage; 178 return 0; /* we know nothing about this usage type */ 179} 180 181/* 182 * Add a usage to the temporary parser table. 183 */ 184 185static int hid_add_usage(struct hid_parser *parser, unsigned usage) 186{ 187 if (parser->local.usage_index >= HID_MAX_USAGES) { 188 dbg_hid("usage index exceeded\n"); 189 return -1; 190 } 191 parser->local.usage[parser->local.usage_index] = usage; 192 parser->local.collection_index[parser->local.usage_index] = 193 parser->collection_stack_ptr ? 194 parser->collection_stack[parser->collection_stack_ptr - 1] : 0; 195 parser->local.usage_index++; 196 return 0; 197} 198 199/* 200 * Register a new field for this report. 201 */ 202 203static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags) 204{ 205 struct hid_report *report; 206 struct hid_field *field; 207 int usages; 208 unsigned offset; 209 int i; 210 211 if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) { 212 dbg_hid("hid_register_report failed\n"); 213 return -1; 214 } 215 216 if (parser->global.logical_maximum < parser->global.logical_minimum) { 217 dbg_hid("logical range invalid %d %d\n", parser->global.logical_minimum, parser->global.logical_maximum); 218 return -1; 219 } 220 221 offset = report->size; 222 report->size += parser->global.report_size * parser->global.report_count; 223 224 if (!parser->local.usage_index) /* Ignore padding fields */ 225 return 0; 226 227 usages = max_t(int, parser->local.usage_index, parser->global.report_count); 228 229 if ((field = hid_register_field(report, usages, parser->global.report_count)) == NULL) 230 return 0; 231 232 field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL); 233 field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL); 234 field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); 235 236 for (i = 0; i < usages; i++) { 237 int j = i; 238 /* Duplicate the last usage we parsed if we have excess values */ 239 if (i >= parser->local.usage_index) 240 j = parser->local.usage_index - 1; 241 field->usage[i].hid = parser->local.usage[j]; 242 field->usage[i].collection_index = 243 parser->local.collection_index[j]; 244 } 245 246 field->maxusage = usages; 247 field->flags = flags; 248 field->report_offset = offset; 249 field->report_type = report_type; 250 field->report_size = parser->global.report_size; 251 field->report_count = parser->global.report_count; 252 field->logical_minimum = parser->global.logical_minimum; 253 field->logical_maximum = parser->global.logical_maximum; 254 field->physical_minimum = parser->global.physical_minimum; 255 field->physical_maximum = parser->global.physical_maximum; 256 field->unit_exponent = parser->global.unit_exponent; 257 field->unit = parser->global.unit; 258 259 return 0; 260} 261 262/* 263 * Read data value from item. 264 */ 265 266static u32 item_udata(struct hid_item *item) 267{ 268 switch (item->size) { 269 case 1: return item->data.u8; 270 case 2: return item->data.u16; 271 case 4: return item->data.u32; 272 } 273 return 0; 274} 275 276static s32 item_sdata(struct hid_item *item) 277{ 278 switch (item->size) { 279 case 1: return item->data.s8; 280 case 2: return item->data.s16; 281 case 4: return item->data.s32; 282 } 283 return 0; 284} 285 286/* 287 * Process a global item. 288 */ 289 290static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) 291{ 292 switch (item->tag) { 293 294 case HID_GLOBAL_ITEM_TAG_PUSH: 295 296 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) { 297 dbg_hid("global enviroment stack overflow\n"); 298 return -1; 299 } 300 301 memcpy(parser->global_stack + parser->global_stack_ptr++, 302 &parser->global, sizeof(struct hid_global)); 303 return 0; 304 305 case HID_GLOBAL_ITEM_TAG_POP: 306 307 if (!parser->global_stack_ptr) { 308 dbg_hid("global enviroment stack underflow\n"); 309 return -1; 310 } 311 312 memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr, 313 sizeof(struct hid_global)); 314 return 0; 315 316 case HID_GLOBAL_ITEM_TAG_USAGE_PAGE: 317 parser->global.usage_page = item_udata(item); 318 return 0; 319 320 case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM: 321 parser->global.logical_minimum = item_sdata(item); 322 return 0; 323 324 case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM: 325 if (parser->global.logical_minimum < 0) 326 parser->global.logical_maximum = item_sdata(item); 327 else 328 parser->global.logical_maximum = item_udata(item); 329 return 0; 330 331 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM: 332 parser->global.physical_minimum = item_sdata(item); 333 return 0; 334 335 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM: 336 if (parser->global.physical_minimum < 0) 337 parser->global.physical_maximum = item_sdata(item); 338 else 339 parser->global.physical_maximum = item_udata(item); 340 return 0; 341 342 case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: 343 parser->global.unit_exponent = item_sdata(item); 344 return 0; 345 346 case HID_GLOBAL_ITEM_TAG_UNIT: 347 parser->global.unit = item_udata(item); 348 return 0; 349 350 case HID_GLOBAL_ITEM_TAG_REPORT_SIZE: 351 if ((parser->global.report_size = item_udata(item)) > 32) { 352 dbg_hid("invalid report_size %d\n", parser->global.report_size); 353 return -1; 354 } 355 return 0; 356 357 case HID_GLOBAL_ITEM_TAG_REPORT_COUNT: 358 if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) { 359 dbg_hid("invalid report_count %d\n", parser->global.report_count); 360 return -1; 361 } 362 return 0; 363 364 case HID_GLOBAL_ITEM_TAG_REPORT_ID: 365 if ((parser->global.report_id = item_udata(item)) == 0) { 366 dbg_hid("report_id 0 is invalid\n"); 367 return -1; 368 } 369 return 0; 370 371 default: 372 dbg_hid("unknown global tag 0x%x\n", item->tag); 373 return -1; 374 } 375} 376 377/* 378 * Process a local item. 379 */ 380 381static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) 382{ 383 __u32 data; 384 unsigned n; 385 386 if (item->size == 0) { 387 dbg_hid("item data expected for local item\n"); 388 return -1; 389 } 390 391 data = item_udata(item); 392 393 switch (item->tag) { 394 395 case HID_LOCAL_ITEM_TAG_DELIMITER: 396 397 if (data) { 398 /* 399 * We treat items before the first delimiter 400 * as global to all usage sets (branch 0). 401 * In the moment we process only these global 402 * items and the first delimiter set. 403 */ 404 if (parser->local.delimiter_depth != 0) { 405 dbg_hid("nested delimiters\n"); 406 return -1; 407 } 408 parser->local.delimiter_depth++; 409 parser->local.delimiter_branch++; 410 } else { 411 if (parser->local.delimiter_depth < 1) { 412 dbg_hid("bogus close delimiter\n"); 413 return -1; 414 } 415 parser->local.delimiter_depth--; 416 } 417 return 1; 418 419 case HID_LOCAL_ITEM_TAG_USAGE: 420 421 if (parser->local.delimiter_branch > 1) { 422 dbg_hid("alternative usage ignored\n"); 423 return 0; 424 } 425 426 if (item->size <= 2) 427 data = (parser->global.usage_page << 16) + data; 428 429 return hid_add_usage(parser, data); 430 431 case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: 432 433 if (parser->local.delimiter_branch > 1) { 434 dbg_hid("alternative usage ignored\n"); 435 return 0; 436 } 437 438 if (item->size <= 2) 439 data = (parser->global.usage_page << 16) + data; 440 441 parser->local.usage_minimum = data; 442 return 0; 443 444 case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: 445 446 if (parser->local.delimiter_branch > 1) { 447 dbg_hid("alternative usage ignored\n"); 448 return 0; 449 } 450 451 if (item->size <= 2) 452 data = (parser->global.usage_page << 16) + data; 453 454 for (n = parser->local.usage_minimum; n <= data; n++) 455 if (hid_add_usage(parser, n)) { 456 dbg_hid("hid_add_usage failed\n"); 457 return -1; 458 } 459 return 0; 460 461 default: 462 463 dbg_hid("unknown local item tag 0x%x\n", item->tag); 464 return 0; 465 } 466 return 0; 467} 468 469/* 470 * Process a main item. 471 */ 472 473static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) 474{ 475 __u32 data; 476 int ret; 477 478 data = item_udata(item); 479 480 switch (item->tag) { 481 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: 482 ret = open_collection(parser, data & 0xff); 483 break; 484 case HID_MAIN_ITEM_TAG_END_COLLECTION: 485 ret = close_collection(parser); 486 break; 487 case HID_MAIN_ITEM_TAG_INPUT: 488 ret = hid_add_field(parser, HID_INPUT_REPORT, data); 489 break; 490 case HID_MAIN_ITEM_TAG_OUTPUT: 491 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data); 492 break; 493 case HID_MAIN_ITEM_TAG_FEATURE: 494 ret = hid_add_field(parser, HID_FEATURE_REPORT, data); 495 break; 496 default: 497 dbg_hid("unknown main item tag 0x%x\n", item->tag); 498 ret = 0; 499 } 500 501 memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */ 502 503 return ret; 504} 505 506/* 507 * Process a reserved item. 508 */ 509 510static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item) 511{ 512 dbg_hid("reserved item type, tag 0x%x\n", item->tag); 513 return 0; 514} 515 516/* 517 * Free a report and all registered fields. The field->usage and 518 * field->value table's are allocated behind the field, so we need 519 * only to free(field) itself. 520 */ 521 522static void hid_free_report(struct hid_report *report) 523{ 524 unsigned n; 525 526 for (n = 0; n < report->maxfield; n++) 527 kfree(report->field[n]); 528 kfree(report); 529} 530 531/* 532 * Free a device structure, all reports, and all fields. 533 */ 534 535void hid_free_device(struct hid_device *device) 536{ 537 unsigned i,j; 538 539 for (i = 0; i < HID_REPORT_TYPES; i++) { 540 struct hid_report_enum *report_enum = device->report_enum + i; 541 542 for (j = 0; j < 256; j++) { 543 struct hid_report *report = report_enum->report_id_hash[j]; 544 if (report) 545 hid_free_report(report); 546 } 547 } 548 549 kfree(device->rdesc); 550 kfree(device->collection); 551 kfree(device); 552} 553EXPORT_SYMBOL_GPL(hid_free_device); 554 555/* 556 * Fetch a report description item from the data stream. We support long 557 * items, though they are not used yet. 558 */ 559 560static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item) 561{ 562 u8 b; 563 564 if ((end - start) <= 0) 565 return NULL; 566 567 b = *start++; 568 569 item->type = (b >> 2) & 3; 570 item->tag = (b >> 4) & 15; 571 572 if (item->tag == HID_ITEM_TAG_LONG) { 573 574 item->format = HID_ITEM_FORMAT_LONG; 575 576 if ((end - start) < 2) 577 return NULL; 578 579 item->size = *start++; 580 item->tag = *start++; 581 582 if ((end - start) < item->size) 583 return NULL; 584 585 item->data.longdata = start; 586 start += item->size; 587 return start; 588 } 589 590 item->format = HID_ITEM_FORMAT_SHORT; 591 item->size = b & 3; 592 593 switch (item->size) { 594 595 case 0: 596 return start; 597 598 case 1: 599 if ((end - start) < 1) 600 return NULL; 601 item->data.u8 = *start++; 602 return start; 603 604 case 2: 605 if ((end - start) < 2) 606 return NULL; 607 item->data.u16 = le16_to_cpu(get_unaligned((__le16*)start)); 608 start = (__u8 *)((__le16 *)start + 1); 609 return start; 610 611 case 3: 612 item->size++; 613 if ((end - start) < 4) 614 return NULL; 615 item->data.u32 = le32_to_cpu(get_unaligned((__le32*)start)); 616 start = (__u8 *)((__le32 *)start + 1); 617 return start; 618 } 619 620 return NULL; 621} 622 623/* 624 * Parse a report description into a hid_device structure. Reports are 625 * enumerated, fields are attached to these reports. 626 */ 627 628struct hid_device *hid_parse_report(__u8 *start, unsigned size) 629{ 630 struct hid_device *device; 631 struct hid_parser *parser; 632 struct hid_item item; 633 __u8 *end; 634 unsigned i; 635 static int (*dispatch_type[])(struct hid_parser *parser, 636 struct hid_item *item) = { 637 hid_parser_main, 638 hid_parser_global, 639 hid_parser_local, 640 hid_parser_reserved 641 }; 642 643 if (!(device = kzalloc(sizeof(struct hid_device), GFP_KERNEL))) 644 return NULL; 645 646 if (!(device->collection = kzalloc(sizeof(struct hid_collection) * 647 HID_DEFAULT_NUM_COLLECTIONS, GFP_KERNEL))) { 648 kfree(device); 649 return NULL; 650 } 651 device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; 652 653 for (i = 0; i < HID_REPORT_TYPES; i++) 654 INIT_LIST_HEAD(&device->report_enum[i].report_list); 655 656 if (!(device->rdesc = kmalloc(size, GFP_KERNEL))) { 657 kfree(device->collection); 658 kfree(device); 659 return NULL; 660 } 661 memcpy(device->rdesc, start, size); 662 device->rsize = size; 663 664 if (!(parser = vmalloc(sizeof(struct hid_parser)))) { 665 kfree(device->rdesc); 666 kfree(device->collection); 667 kfree(device); 668 return NULL; 669 } 670 memset(parser, 0, sizeof(struct hid_parser)); 671 parser->device = device; 672 673 end = start + size; 674 while ((start = fetch_item(start, end, &item)) != NULL) { 675 676 if (item.format != HID_ITEM_FORMAT_SHORT) { 677 dbg_hid("unexpected long global item\n"); 678 hid_free_device(device); 679 vfree(parser); 680 return NULL; 681 } 682 683 if (dispatch_type[item.type](parser, &item)) { 684 dbg_hid("item %u %u %u %u parsing failed\n", 685 item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag); 686 hid_free_device(device); 687 vfree(parser); 688 return NULL; 689 } 690 691 if (start == end) { 692 if (parser->collection_stack_ptr) { 693 dbg_hid("unbalanced collection at end of report description\n"); 694 hid_free_device(device); 695 vfree(parser); 696 return NULL; 697 } 698 if (parser->local.delimiter_depth) { 699 dbg_hid("unbalanced delimiter at end of report description\n"); 700 hid_free_device(device); 701 vfree(parser); 702 return NULL; 703 } 704 vfree(parser); 705 return device; 706 } 707 } 708 709 dbg_hid("item fetching failed at offset %d\n", (int)(end - start)); 710 hid_free_device(device); 711 vfree(parser); 712 return NULL; 713} 714EXPORT_SYMBOL_GPL(hid_parse_report); 715 716/* 717 * Convert a signed n-bit integer to signed 32-bit integer. Common 718 * cases are done through the compiler, the screwed things has to be 719 * done by hand. 720 */ 721 722static s32 snto32(__u32 value, unsigned n) 723{ 724 switch (n) { 725 case 8: return ((__s8)value); 726 case 16: return ((__s16)value); 727 case 32: return ((__s32)value); 728 } 729 return value & (1 << (n - 1)) ? value | (-1 << n) : value; 730} 731 732/* 733 * Convert a signed 32-bit integer to a signed n-bit integer. 734 */ 735 736static u32 s32ton(__s32 value, unsigned n) 737{ 738 s32 a = value >> (n - 1); 739 if (a && a != -1) 740 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; 741 return value & ((1 << n) - 1); 742} 743 744/* 745 * Extract/implement a data field from/to a little endian report (bit array). 746 * 747 * Code sort-of follows HID spec: 748 * http://www.usb.org/developers/devclass_docs/HID1_11.pdf 749 * 750 * While the USB HID spec allows unlimited length bit fields in "report 751 * descriptors", most devices never use more than 16 bits. 752 * One model of UPS is claimed to report "LINEV" as a 32-bit field. 753 * Search linux-kernel and linux-usb-devel archives for "hid-core extract". 754 */ 755 756static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n) 757{ 758 u64 x; 759 760 WARN_ON(n > 32); 761 762 report += offset >> 3; /* adjust byte index */ 763 offset &= 7; /* now only need bit offset into one byte */ 764 x = le64_to_cpu(get_unaligned((__le64 *) report)); 765 x = (x >> offset) & ((1ULL << n) - 1); /* extract bit field */ 766 return (u32) x; 767} 768 769/* 770 * "implement" : set bits in a little endian bit stream. 771 * Same concepts as "extract" (see comments above). 772 * The data mangled in the bit stream remains in little endian 773 * order the whole time. It make more sense to talk about 774 * endianness of register values by considering a register 775 * a "cached" copy of the little endiad bit stream. 776 */ 777static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value) 778{ 779 __le64 x; 780 u64 m = (1ULL << n) - 1; 781 782 WARN_ON(n > 32); 783 784 WARN_ON(value > m); 785 value &= m; 786 787 report += offset >> 3; 788 offset &= 7; 789 790 x = get_unaligned((__le64 *)report); 791 x &= cpu_to_le64(~(m << offset)); 792 x |= cpu_to_le64(((u64) value) << offset); 793 put_unaligned(x, (__le64 *) report); 794} 795 796/* 797 * Search an array for a value. 798 */ 799 800static __inline__ int search(__s32 *array, __s32 value, unsigned n) 801{ 802 while (n--) { 803 if (*array++ == value) 804 return 0; 805 } 806 return -1; 807} 808 809static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt) 810{ 811 hid_dump_input(usage, value); 812 if (hid->claimed & HID_CLAIMED_INPUT) 813 hidinput_hid_event(hid, field, usage, value); 814 if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) 815 hid->hiddev_hid_event(hid, field, usage, value); 816} 817 818/* 819 * Analyse a received field, and fetch the data from it. The field 820 * content is stored for next report processing (we do differential 821 * reporting to the layer). 822 */ 823 824void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt) 825{ 826 unsigned n; 827 unsigned count = field->report_count; 828 unsigned offset = field->report_offset; 829 unsigned size = field->report_size; 830 __s32 min = field->logical_minimum; 831 __s32 max = field->logical_maximum; 832 __s32 *value; 833 834 if (!(value = kmalloc(sizeof(__s32) * count, GFP_ATOMIC))) 835 return; 836 837 for (n = 0; n < count; n++) { 838 839 value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) : 840 extract(data, offset + n * size, size); 841 842 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) /* Ignore report if ErrorRollOver */ 843 && value[n] >= min && value[n] <= max 844 && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) 845 goto exit; 846 } 847 848 for (n = 0; n < count; n++) { 849 850 if (HID_MAIN_ITEM_VARIABLE & field->flags) { 851 hid_process_event(hid, field, &field->usage[n], value[n], interrupt); 852 continue; 853 } 854 855 if (field->value[n] >= min && field->value[n] <= max 856 && field->usage[field->value[n] - min].hid 857 && search(value, field->value[n], count)) 858 hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); 859 860 if (value[n] >= min && value[n] <= max 861 && field->usage[value[n] - min].hid 862 && search(field->value, value[n], count)) 863 hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); 864 } 865 866 memcpy(field->value, value, count * sizeof(__s32)); 867exit: 868 kfree(value); 869} 870EXPORT_SYMBOL_GPL(hid_input_field); 871 872/* 873 * Output the field into the report. 874 */ 875 876static void hid_output_field(struct hid_field *field, __u8 *data) 877{ 878 unsigned count = field->report_count; 879 unsigned offset = field->report_offset; 880 unsigned size = field->report_size; 881 unsigned bitsused = offset + count * size; 882 unsigned n; 883 884 /* make sure the unused bits in the last byte are zeros */ 885 if (count > 0 && size > 0 && (bitsused % 8) != 0) 886 data[(bitsused-1)/8] &= (1 << (bitsused % 8)) - 1; 887 888 for (n = 0; n < count; n++) { 889 if (field->logical_minimum < 0) /* signed values */ 890 implement(data, offset + n * size, size, s32ton(field->value[n], size)); 891 else /* unsigned values */ 892 implement(data, offset + n * size, size, field->value[n]); 893 } 894} 895 896/* 897 * Create a report. 898 */ 899 900void hid_output_report(struct hid_report *report, __u8 *data) 901{ 902 unsigned n; 903 904 if (report->id > 0) 905 *data++ = report->id; 906 907 for (n = 0; n < report->maxfield; n++) 908 hid_output_field(report->field[n], data); 909} 910EXPORT_SYMBOL_GPL(hid_output_report); 911 912/* 913 * Set a field value. The report this field belongs to has to be 914 * created and transferred to the device, to set this value in the 915 * device. 916 */ 917 918int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) 919{ 920 unsigned size = field->report_size; 921 922 hid_dump_input(field->usage + offset, value); 923 924 if (offset >= field->report_count) { 925 dbg_hid("offset (%d) exceeds report_count (%d)\n", offset, field->report_count); 926 hid_dump_field(field, 8); 927 return -1; 928 } 929 if (field->logical_minimum < 0) { 930 if (value != snto32(s32ton(value, size), size)) { 931 dbg_hid("value %d is out of range\n", value); 932 return -1; 933 } 934 } 935 field->value[offset] = value; 936 return 0; 937} 938EXPORT_SYMBOL_GPL(hid_set_field); 939 940int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt) 941{ 942 struct hid_report_enum *report_enum = hid->report_enum + type; 943 struct hid_report *report; 944 int n, rsize, i; 945 946 if (!hid) 947 return -ENODEV; 948 949 if (!size) { 950 dbg_hid("empty report\n"); 951 return -1; 952 } 953 954 dbg_hid("report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un"); 955 956 n = 0; /* Normally report number is 0 */ 957 if (report_enum->numbered) { /* Device uses numbered reports, data[0] is report number */ 958 n = *data++; 959 size--; 960 } 961 962 /* dump the report descriptor */ 963 dbg_hid("report %d (size %u) = ", n, size); 964 for (i = 0; i < size; i++) 965 dbg_hid_line(" %02x", data[i]); 966 dbg_hid_line("\n"); 967 968 if (!(report = report_enum->report_id_hash[n])) { 969 dbg_hid("undefined report_id %d received\n", n); 970 return -1; 971 } 972 973 rsize = ((report->size - 1) >> 3) + 1; 974 975 if (size < rsize) { 976 dbg_hid("report %d is too short, (%d < %d)\n", report->id, size, rsize); 977 memset(data + size, 0, rsize - size); 978 } 979 980 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) 981 hid->hiddev_report_event(hid, report); 982 983 for (n = 0; n < report->maxfield; n++) 984 hid_input_field(hid, report->field[n], data, interrupt); 985 986 if (hid->claimed & HID_CLAIMED_INPUT) 987 hidinput_report_event(hid, report); 988 989 return 0; 990} 991EXPORT_SYMBOL_GPL(hid_input_report); 992 993MODULE_LICENSE(DRIVER_LICENSE); 994 995