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/sched.h> 22 #include <linux/list.h> 23 #include <linux/mm.h> 24 #include <linux/smp_lock.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 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 48 static 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 77 static 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 */ 101 102 static 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 */ 150 151 static 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 */ 165 166 static 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 */ 178 179 static 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 */ 196 197 static 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 */ 259 260 static 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 } 269 270 static 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 */ 283 284 static 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 */ 374 375 static 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 */ 466 467 static 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 */ 503 504 static 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 */ 515 516 static 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 */ 528 529 void 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 } 547 EXPORT_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 */ 553 554 static 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 */ 621 622 struct 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 = kzalloc(sizeof(struct hid_parser), GFP_KERNEL))) { 659 kfree(device->rdesc); 660 kfree(device->collection); 661 kfree(device); 662 return NULL; 663 } 664 parser->device = device; 665 666 end = start + size; 667 while ((start = fetch_item(start, end, &item)) != NULL) { 668 669 if (item.format != HID_ITEM_FORMAT_SHORT) { 670 dbg("unexpected long global item"); 671 kfree(device->collection); 672 hid_free_device(device); 673 kfree(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 kfree(device->collection); 681 hid_free_device(device); 682 kfree(parser); 683 return NULL; 684 } 685 686 if (start == end) { 687 if (parser->collection_stack_ptr) { 688 dbg("unbalanced collection at end of report description"); 689 kfree(device->collection); 690 hid_free_device(device); 691 kfree(parser); 692 return NULL; 693 } 694 if (parser->local.delimiter_depth) { 695 dbg("unbalanced delimiter at end of report description"); 696 kfree(device->collection); 697 hid_free_device(device); 698 kfree(parser); 699 return NULL; 700 } 701 kfree(parser); 702 return device; 703 } 704 } 705 706 dbg("item fetching failed at offset %d\n", (int)(end - start)); 707 kfree(device->collection); 708 hid_free_device(device); 709 kfree(parser); 710 return NULL; 711 } 712 EXPORT_SYMBOL_GPL(hid_parse_report); 713 714 /* 715 * Convert a signed n-bit integer to signed 32-bit integer. Common 716 * cases are done through the compiler, the screwed things has to be 717 * done by hand. 718 */ 719 720 static s32 snto32(__u32 value, unsigned n) 721 { 722 switch (n) { 723 case 8: return ((__s8)value); 724 case 16: return ((__s16)value); 725 case 32: return ((__s32)value); 726 } 727 return value & (1 << (n - 1)) ? value | (-1 << n) : value; 728 } 729 730 /* 731 * Convert a signed 32-bit integer to a signed n-bit integer. 732 */ 733 734 static u32 s32ton(__s32 value, unsigned n) 735 { 736 s32 a = value >> (n - 1); 737 if (a && a != -1) 738 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; 739 return value & ((1 << n) - 1); 740 } 741 742 /* 743 * Extract/implement a data field from/to a little endian report (bit array). 744 * 745 * Code sort-of follows HID spec: 746 * http://www.usb.org/developers/devclass_docs/HID1_11.pdf 747 * 748 * While the USB HID spec allows unlimited length bit fields in "report 749 * descriptors", most devices never use more than 16 bits. 750 * One model of UPS is claimed to report "LINEV" as a 32-bit field. 751 * Search linux-kernel and linux-usb-devel archives for "hid-core extract". 752 */ 753 754 static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n) 755 { 756 u64 x; 757 758 WARN_ON(n > 32); 759 760 report += offset >> 3; /* adjust byte index */ 761 offset &= 7; /* now only need bit offset into one byte */ 762 x = get_unaligned((u64 *) report); 763 x = le64_to_cpu(x); 764 x = (x >> offset) & ((1ULL << n) - 1); /* extract bit field */ 765 return (u32) x; 766 } 767 768 /* 769 * "implement" : set bits in a little endian bit stream. 770 * Same concepts as "extract" (see comments above). 771 * The data mangled in the bit stream remains in little endian 772 * order the whole time. It make more sense to talk about 773 * endianness of register values by considering a register 774 * a "cached" copy of the little endiad bit stream. 775 */ 776 static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value) 777 { 778 u64 x; 779 u64 m = (1ULL << n) - 1; 780 781 WARN_ON(n > 32); 782 783 WARN_ON(value > m); 784 value &= m; 785 786 report += offset >> 3; 787 offset &= 7; 788 789 x = get_unaligned((u64 *)report); 790 x &= cpu_to_le64(~(m << offset)); 791 x |= cpu_to_le64(((u64) value) << offset); 792 put_unaligned(x, (u64 *) report); 793 } 794 795 /* 796 * Search an array for a value. 797 */ 798 799 static __inline__ int search(__s32 *array, __s32 value, unsigned n) 800 { 801 while (n--) { 802 if (*array++ == value) 803 return 0; 804 } 805 return -1; 806 } 807 808 static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt) 809 { 810 hid_dump_input(usage, value); 811 if (hid->claimed & HID_CLAIMED_INPUT) 812 hidinput_hid_event(hid, field, usage, value); 813 if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) 814 hid->hiddev_hid_event(hid, field, usage, value); 815 } 816 817 /* 818 * Analyse a received field, and fetch the data from it. The field 819 * content is stored for next report processing (we do differential 820 * reporting to the layer). 821 */ 822 823 void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt) 824 { 825 unsigned n; 826 unsigned count = field->report_count; 827 unsigned offset = field->report_offset; 828 unsigned size = field->report_size; 829 __s32 min = field->logical_minimum; 830 __s32 max = field->logical_maximum; 831 __s32 *value; 832 833 if (!(value = kmalloc(sizeof(__s32) * count, GFP_ATOMIC))) 834 return; 835 836 for (n = 0; n < count; n++) { 837 838 value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) : 839 extract(data, offset + n * size, size); 840 841 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) /* Ignore report if ErrorRollOver */ 842 && value[n] >= min && value[n] <= max 843 && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) 844 goto exit; 845 } 846 847 for (n = 0; n < count; n++) { 848 849 if (HID_MAIN_ITEM_VARIABLE & field->flags) { 850 hid_process_event(hid, field, &field->usage[n], value[n], interrupt); 851 continue; 852 } 853 854 if (field->value[n] >= min && field->value[n] <= max 855 && field->usage[field->value[n] - min].hid 856 && search(value, field->value[n], count)) 857 hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); 858 859 if (value[n] >= min && value[n] <= max 860 && field->usage[value[n] - min].hid 861 && search(field->value, value[n], count)) 862 hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); 863 } 864 865 memcpy(field->value, value, count * sizeof(__s32)); 866 exit: 867 kfree(value); 868 } 869 EXPORT_SYMBOL_GPL(hid_input_field); 870 871 /* 872 * Output the field into the report. 873 */ 874 875 static void hid_output_field(struct hid_field *field, __u8 *data) 876 { 877 unsigned count = field->report_count; 878 unsigned offset = field->report_offset; 879 unsigned size = field->report_size; 880 unsigned n; 881 882 /* make sure the unused bits in the last byte are zeros */ 883 if (count > 0 && size > 0) 884 data[(count*size-1)/8] = 0; 885 886 for (n = 0; n < count; n++) { 887 if (field->logical_minimum < 0) /* signed values */ 888 implement(data, offset + n * size, size, s32ton(field->value[n], size)); 889 else /* unsigned values */ 890 implement(data, offset + n * size, size, field->value[n]); 891 } 892 } 893 894 /* 895 * Create a report. 896 */ 897 898 void hid_output_report(struct hid_report *report, __u8 *data) 899 { 900 unsigned n; 901 902 if (report->id > 0) 903 *data++ = report->id; 904 905 for (n = 0; n < report->maxfield; n++) 906 hid_output_field(report->field[n], data); 907 } 908 EXPORT_SYMBOL_GPL(hid_output_report); 909 910 /* 911 * Set a field value. The report this field belongs to has to be 912 * created and transferred to the device, to set this value in the 913 * device. 914 */ 915 916 int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) 917 { 918 unsigned size = field->report_size; 919 920 hid_dump_input(field->usage + offset, value); 921 922 if (offset >= field->report_count) { 923 dbg("offset (%d) exceeds report_count (%d)", offset, field->report_count); 924 hid_dump_field(field, 8); 925 return -1; 926 } 927 if (field->logical_minimum < 0) { 928 if (value != snto32(s32ton(value, size), size)) { 929 dbg("value %d is out of range", value); 930 return -1; 931 } 932 } 933 field->value[offset] = value; 934 return 0; 935 } 936 EXPORT_SYMBOL_GPL(hid_set_field); 937 938 int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt) 939 { 940 struct hid_report_enum *report_enum = hid->report_enum + type; 941 struct hid_report *report; 942 int n, rsize; 943 944 if (!hid) 945 return -ENODEV; 946 947 if (!size) { 948 dbg("empty report"); 949 return -1; 950 } 951 952 #ifdef CONFIG_HID_DEBUG 953 printk(KERN_DEBUG __FILE__ ": report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un"); 954 #endif 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 #ifdef CONFIG_HID_DEBUG 963 { 964 int i; 965 printk(KERN_DEBUG __FILE__ ": report %d (size %u) = ", n, size); 966 for (i = 0; i < size; i++) 967 printk(" %02x", data[i]); 968 printk("\n"); 969 } 970 #endif 971 972 if (!(report = report_enum->report_id_hash[n])) { 973 dbg("undefined report_id %d received", n); 974 return -1; 975 } 976 977 rsize = ((report->size - 1) >> 3) + 1; 978 979 if (size < rsize) { 980 dbg("report %d is too short, (%d < %d)", report->id, size, rsize); 981 return -1; 982 } 983 984 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) 985 hid->hiddev_report_event(hid, report); 986 987 for (n = 0; n < report->maxfield; n++) 988 hid_input_field(hid, report->field[n], data, interrupt); 989 990 if (hid->claimed & HID_CLAIMED_INPUT) 991 hidinput_report_event(hid, report); 992 993 return 0; 994 } 995 EXPORT_SYMBOL_GPL(hid_input_report); 996 997 MODULE_LICENSE(DRIVER_LICENSE); 998 999