1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * HID support for Linux 4 * 5 * Copyright (c) 1999 Andreas Gal 6 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz> 7 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc 8 * Copyright (c) 2006-2012 Jiri Kosina 9 */ 10 11 /* 12 */ 13 14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 #include <linux/init.h> 19 #include <linux/kernel.h> 20 #include <linux/list.h> 21 #include <linux/mm.h> 22 #include <linux/spinlock.h> 23 #include <linux/unaligned.h> 24 #include <asm/byteorder.h> 25 #include <linux/input.h> 26 #include <linux/wait.h> 27 #include <linux/vmalloc.h> 28 #include <linux/sched.h> 29 #include <linux/semaphore.h> 30 31 #include <linux/hid.h> 32 #include <linux/hiddev.h> 33 #include <linux/hid-debug.h> 34 #include <linux/hidraw.h> 35 36 #include "hid-ids.h" 37 38 /* 39 * Version Information 40 */ 41 42 #define DRIVER_DESC "HID core driver" 43 44 static int hid_ignore_special_drivers = 0; 45 module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600); 46 MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver"); 47 48 /* 49 * Convert a signed n-bit integer to signed 32-bit integer. 50 */ 51 52 static s32 snto32(__u32 value, unsigned int n) 53 { 54 if (!value || !n) 55 return 0; 56 57 if (n > 32) 58 n = 32; 59 60 return sign_extend32(value, n - 1); 61 } 62 63 /* 64 * Convert a signed 32-bit integer to a signed n-bit integer. 65 */ 66 67 static u32 s32ton(__s32 value, unsigned int n) 68 { 69 s32 a; 70 71 if (!value || !n) 72 return 0; 73 74 a = value >> (n - 1); 75 if (a && a != -1) 76 return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; 77 return value & ((1 << n) - 1); 78 } 79 80 /* 81 * Register a new report for a device. 82 */ 83 84 struct hid_report *hid_register_report(struct hid_device *device, 85 enum hid_report_type type, unsigned int id, 86 unsigned int application) 87 { 88 struct hid_report_enum *report_enum = device->report_enum + type; 89 struct hid_report *report; 90 91 if (id >= HID_MAX_IDS) 92 return NULL; 93 if (report_enum->report_id_hash[id]) 94 return report_enum->report_id_hash[id]; 95 96 report = kzalloc_obj(struct hid_report, GFP_KERNEL); 97 if (!report) 98 return NULL; 99 100 if (id != 0) 101 report_enum->numbered = 1; 102 103 report->id = id; 104 report->type = type; 105 report->size = 0; 106 report->device = device; 107 report->application = application; 108 report_enum->report_id_hash[id] = report; 109 110 list_add_tail(&report->list, &report_enum->report_list); 111 INIT_LIST_HEAD(&report->field_entry_list); 112 113 return report; 114 } 115 EXPORT_SYMBOL_GPL(hid_register_report); 116 117 /* 118 * Register a new field for this report. 119 */ 120 121 static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages) 122 { 123 struct hid_field *field; 124 125 if (report->maxfield == HID_MAX_FIELDS) { 126 hid_err(report->device, "too many fields in report\n"); 127 return NULL; 128 } 129 130 field = kvzalloc((sizeof(struct hid_field) + 131 usages * sizeof(struct hid_usage) + 132 3 * usages * sizeof(unsigned int)), GFP_KERNEL); 133 if (!field) 134 return NULL; 135 136 field->index = report->maxfield++; 137 report->field[field->index] = field; 138 field->usage = (struct hid_usage *)(field + 1); 139 field->value = (s32 *)(field->usage + usages); 140 field->new_value = (s32 *)(field->value + usages); 141 field->usages_priorities = (s32 *)(field->new_value + usages); 142 field->report = report; 143 144 return field; 145 } 146 147 /* 148 * Open a collection. The type/usage is pushed on the stack. 149 */ 150 151 static int open_collection(struct hid_parser *parser, unsigned type) 152 { 153 struct hid_collection *collection; 154 unsigned usage; 155 int collection_index; 156 157 usage = parser->local.usage[0]; 158 159 if (parser->collection_stack_ptr == parser->collection_stack_size) { 160 unsigned int *collection_stack; 161 unsigned int new_size = parser->collection_stack_size + 162 HID_COLLECTION_STACK_SIZE; 163 164 collection_stack = krealloc(parser->collection_stack, 165 new_size * sizeof(unsigned int), 166 GFP_KERNEL); 167 if (!collection_stack) 168 return -ENOMEM; 169 170 parser->collection_stack = collection_stack; 171 parser->collection_stack_size = new_size; 172 } 173 174 if (parser->device->maxcollection == parser->device->collection_size) { 175 collection = kmalloc( 176 array3_size(sizeof(struct hid_collection), 177 parser->device->collection_size, 178 2), 179 GFP_KERNEL); 180 if (collection == NULL) { 181 hid_err(parser->device, "failed to reallocate collection array\n"); 182 return -ENOMEM; 183 } 184 memcpy(collection, parser->device->collection, 185 sizeof(struct hid_collection) * 186 parser->device->collection_size); 187 memset(collection + parser->device->collection_size, 0, 188 sizeof(struct hid_collection) * 189 parser->device->collection_size); 190 kfree(parser->device->collection); 191 parser->device->collection = collection; 192 parser->device->collection_size *= 2; 193 } 194 195 parser->collection_stack[parser->collection_stack_ptr++] = 196 parser->device->maxcollection; 197 198 collection_index = parser->device->maxcollection++; 199 collection = parser->device->collection + collection_index; 200 collection->type = type; 201 collection->usage = usage; 202 collection->level = parser->collection_stack_ptr - 1; 203 collection->parent_idx = (collection->level == 0) ? -1 : 204 parser->collection_stack[collection->level - 1]; 205 206 if (type == HID_COLLECTION_APPLICATION) 207 parser->device->maxapplication++; 208 209 return 0; 210 } 211 212 /* 213 * Close a collection. 214 */ 215 216 static int close_collection(struct hid_parser *parser) 217 { 218 if (!parser->collection_stack_ptr) { 219 hid_err(parser->device, "collection stack underflow\n"); 220 return -EINVAL; 221 } 222 parser->collection_stack_ptr--; 223 return 0; 224 } 225 226 /* 227 * Climb up the stack, search for the specified collection type 228 * and return the usage. 229 */ 230 231 static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) 232 { 233 struct hid_collection *collection = parser->device->collection; 234 int n; 235 236 for (n = parser->collection_stack_ptr - 1; n >= 0; n--) { 237 unsigned index = parser->collection_stack[n]; 238 if (collection[index].type == type) 239 return collection[index].usage; 240 } 241 return 0; /* we know nothing about this usage type */ 242 } 243 244 /* 245 * Concatenate usage which defines 16 bits or less with the 246 * currently defined usage page to form a 32 bit usage 247 */ 248 249 static void complete_usage(struct hid_parser *parser, unsigned int index) 250 { 251 parser->local.usage[index] &= 0xFFFF; 252 parser->local.usage[index] |= 253 (parser->global.usage_page & 0xFFFF) << 16; 254 } 255 256 /* 257 * Add a usage to the temporary parser table. 258 */ 259 260 static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size) 261 { 262 if (parser->local.usage_index >= HID_MAX_USAGES) { 263 hid_err(parser->device, "usage index exceeded\n"); 264 return -1; 265 } 266 parser->local.usage[parser->local.usage_index] = usage; 267 268 /* 269 * If Usage item only includes usage id, concatenate it with 270 * currently defined usage page 271 */ 272 if (size <= 2) 273 complete_usage(parser, parser->local.usage_index); 274 275 parser->local.usage_size[parser->local.usage_index] = size; 276 parser->local.collection_index[parser->local.usage_index] = 277 parser->collection_stack_ptr ? 278 parser->collection_stack[parser->collection_stack_ptr - 1] : 0; 279 parser->local.usage_index++; 280 return 0; 281 } 282 283 /* 284 * Register a new field for this report. 285 */ 286 287 static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags) 288 { 289 struct hid_report *report; 290 struct hid_field *field; 291 unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE; 292 unsigned int usages; 293 unsigned int offset; 294 unsigned int i; 295 unsigned int application; 296 297 application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); 298 299 report = hid_register_report(parser->device, report_type, 300 parser->global.report_id, application); 301 if (!report) { 302 hid_err(parser->device, "hid_register_report failed\n"); 303 return -1; 304 } 305 306 /* Handle both signed and unsigned cases properly */ 307 if ((parser->global.logical_minimum < 0 && 308 parser->global.logical_maximum < 309 parser->global.logical_minimum) || 310 (parser->global.logical_minimum >= 0 && 311 (__u32)parser->global.logical_maximum < 312 (__u32)parser->global.logical_minimum)) { 313 dbg_hid("logical range invalid 0x%x 0x%x\n", 314 parser->global.logical_minimum, 315 parser->global.logical_maximum); 316 return -1; 317 } 318 319 offset = report->size; 320 report->size += parser->global.report_size * parser->global.report_count; 321 322 if (parser->device->ll_driver->max_buffer_size) 323 max_buffer_size = parser->device->ll_driver->max_buffer_size; 324 325 /* Total size check: Allow for possible report index byte */ 326 if (report->size > (max_buffer_size - 1) << 3) { 327 hid_err(parser->device, "report is too long\n"); 328 return -1; 329 } 330 331 if (!parser->local.usage_index) /* Ignore padding fields */ 332 return 0; 333 334 usages = max_t(unsigned, parser->local.usage_index, 335 parser->global.report_count); 336 337 field = hid_register_field(report, usages); 338 if (!field) 339 return 0; 340 341 field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL); 342 field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL); 343 field->application = application; 344 345 for (i = 0; i < usages; i++) { 346 unsigned j = i; 347 /* Duplicate the last usage we parsed if we have excess values */ 348 if (i >= parser->local.usage_index) 349 j = parser->local.usage_index - 1; 350 field->usage[i].hid = parser->local.usage[j]; 351 field->usage[i].collection_index = 352 parser->local.collection_index[j]; 353 field->usage[i].usage_index = i; 354 field->usage[i].resolution_multiplier = 1; 355 } 356 357 field->maxusage = usages; 358 field->flags = flags; 359 field->report_offset = offset; 360 field->report_type = report_type; 361 field->report_size = parser->global.report_size; 362 field->report_count = parser->global.report_count; 363 field->logical_minimum = parser->global.logical_minimum; 364 field->logical_maximum = parser->global.logical_maximum; 365 field->physical_minimum = parser->global.physical_minimum; 366 field->physical_maximum = parser->global.physical_maximum; 367 field->unit_exponent = parser->global.unit_exponent; 368 field->unit = parser->global.unit; 369 370 return 0; 371 } 372 373 /* 374 * Read data value from item. 375 */ 376 377 static u32 item_udata(struct hid_item *item) 378 { 379 switch (item->size) { 380 case 1: return item->data.u8; 381 case 2: return item->data.u16; 382 case 4: return item->data.u32; 383 } 384 return 0; 385 } 386 387 static s32 item_sdata(struct hid_item *item) 388 { 389 switch (item->size) { 390 case 1: return item->data.s8; 391 case 2: return item->data.s16; 392 case 4: return item->data.s32; 393 } 394 return 0; 395 } 396 397 /* 398 * Process a global item. 399 */ 400 401 static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) 402 { 403 __s32 raw_value; 404 switch (item->tag) { 405 case HID_GLOBAL_ITEM_TAG_PUSH: 406 407 if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) { 408 hid_err(parser->device, "global environment stack overflow\n"); 409 return -1; 410 } 411 412 memcpy(parser->global_stack + parser->global_stack_ptr++, 413 &parser->global, sizeof(struct hid_global)); 414 return 0; 415 416 case HID_GLOBAL_ITEM_TAG_POP: 417 418 if (!parser->global_stack_ptr) { 419 hid_err(parser->device, "global environment stack underflow\n"); 420 return -1; 421 } 422 423 memcpy(&parser->global, parser->global_stack + 424 --parser->global_stack_ptr, sizeof(struct hid_global)); 425 return 0; 426 427 case HID_GLOBAL_ITEM_TAG_USAGE_PAGE: 428 parser->global.usage_page = item_udata(item); 429 return 0; 430 431 case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM: 432 parser->global.logical_minimum = item_sdata(item); 433 return 0; 434 435 case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM: 436 if (parser->global.logical_minimum < 0) 437 parser->global.logical_maximum = item_sdata(item); 438 else 439 parser->global.logical_maximum = item_udata(item); 440 return 0; 441 442 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM: 443 parser->global.physical_minimum = item_sdata(item); 444 return 0; 445 446 case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM: 447 if (parser->global.physical_minimum < 0) 448 parser->global.physical_maximum = item_sdata(item); 449 else 450 parser->global.physical_maximum = item_udata(item); 451 return 0; 452 453 case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: 454 /* Many devices provide unit exponent as a two's complement 455 * nibble due to the common misunderstanding of HID 456 * specification 1.11, 6.2.2.7 Global Items. Attempt to handle 457 * both this and the standard encoding. */ 458 raw_value = item_sdata(item); 459 if (!(raw_value & 0xfffffff0)) 460 parser->global.unit_exponent = snto32(raw_value, 4); 461 else 462 parser->global.unit_exponent = raw_value; 463 return 0; 464 465 case HID_GLOBAL_ITEM_TAG_UNIT: 466 parser->global.unit = item_udata(item); 467 return 0; 468 469 case HID_GLOBAL_ITEM_TAG_REPORT_SIZE: 470 parser->global.report_size = item_udata(item); 471 if (parser->global.report_size > 256) { 472 hid_err(parser->device, "invalid report_size %d\n", 473 parser->global.report_size); 474 return -1; 475 } 476 return 0; 477 478 case HID_GLOBAL_ITEM_TAG_REPORT_COUNT: 479 parser->global.report_count = item_udata(item); 480 if (parser->global.report_count > HID_MAX_USAGES) { 481 hid_err(parser->device, "invalid report_count %d\n", 482 parser->global.report_count); 483 return -1; 484 } 485 return 0; 486 487 case HID_GLOBAL_ITEM_TAG_REPORT_ID: 488 parser->global.report_id = item_udata(item); 489 if (parser->global.report_id == 0 || 490 parser->global.report_id >= HID_MAX_IDS) { 491 hid_err(parser->device, "report_id %u is invalid\n", 492 parser->global.report_id); 493 return -1; 494 } 495 return 0; 496 497 default: 498 hid_err(parser->device, "unknown global tag 0x%x\n", item->tag); 499 return -1; 500 } 501 } 502 503 /* 504 * Process a local item. 505 */ 506 507 static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) 508 { 509 __u32 data; 510 unsigned n; 511 __u32 count; 512 513 data = item_udata(item); 514 515 switch (item->tag) { 516 case HID_LOCAL_ITEM_TAG_DELIMITER: 517 518 if (data) { 519 /* 520 * We treat items before the first delimiter 521 * as global to all usage sets (branch 0). 522 * In the moment we process only these global 523 * items and the first delimiter set. 524 */ 525 if (parser->local.delimiter_depth != 0) { 526 hid_err(parser->device, "nested delimiters\n"); 527 return -1; 528 } 529 parser->local.delimiter_depth++; 530 parser->local.delimiter_branch++; 531 } else { 532 if (parser->local.delimiter_depth < 1) { 533 hid_err(parser->device, "bogus close delimiter\n"); 534 return -1; 535 } 536 parser->local.delimiter_depth--; 537 } 538 return 0; 539 540 case HID_LOCAL_ITEM_TAG_USAGE: 541 542 if (parser->local.delimiter_branch > 1) { 543 dbg_hid("alternative usage ignored\n"); 544 return 0; 545 } 546 547 return hid_add_usage(parser, data, item->size); 548 549 case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: 550 551 if (parser->local.delimiter_branch > 1) { 552 dbg_hid("alternative usage ignored\n"); 553 return 0; 554 } 555 556 parser->local.usage_minimum = data; 557 return 0; 558 559 case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: 560 561 if (parser->local.delimiter_branch > 1) { 562 dbg_hid("alternative usage ignored\n"); 563 return 0; 564 } 565 566 count = data - parser->local.usage_minimum; 567 if (count + parser->local.usage_index >= HID_MAX_USAGES) { 568 /* 569 * We do not warn if the name is not set, we are 570 * actually pre-scanning the device. 571 */ 572 if (dev_name(&parser->device->dev)) 573 hid_warn(parser->device, 574 "ignoring exceeding usage max\n"); 575 data = HID_MAX_USAGES - parser->local.usage_index + 576 parser->local.usage_minimum - 1; 577 if (data <= 0) { 578 hid_err(parser->device, 579 "no more usage index available\n"); 580 return -1; 581 } 582 } 583 584 for (n = parser->local.usage_minimum; n <= data; n++) 585 if (hid_add_usage(parser, n, item->size)) { 586 dbg_hid("hid_add_usage failed\n"); 587 return -1; 588 } 589 return 0; 590 591 default: 592 593 dbg_hid("unknown local item tag 0x%x\n", item->tag); 594 return 0; 595 } 596 return 0; 597 } 598 599 /* 600 * Concatenate Usage Pages into Usages where relevant: 601 * As per specification, 6.2.2.8: "When the parser encounters a main item it 602 * concatenates the last declared Usage Page with a Usage to form a complete 603 * usage value." 604 */ 605 606 static void hid_concatenate_last_usage_page(struct hid_parser *parser) 607 { 608 int i; 609 unsigned int usage_page; 610 unsigned int current_page; 611 612 if (!parser->local.usage_index) 613 return; 614 615 usage_page = parser->global.usage_page; 616 617 /* 618 * Concatenate usage page again only if last declared Usage Page 619 * has not been already used in previous usages concatenation 620 */ 621 for (i = parser->local.usage_index - 1; i >= 0; i--) { 622 if (parser->local.usage_size[i] > 2) 623 /* Ignore extended usages */ 624 continue; 625 626 current_page = parser->local.usage[i] >> 16; 627 if (current_page == usage_page) 628 break; 629 630 complete_usage(parser, i); 631 } 632 } 633 634 /* 635 * Process a main item. 636 */ 637 638 static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) 639 { 640 __u32 data; 641 int ret; 642 643 hid_concatenate_last_usage_page(parser); 644 645 data = item_udata(item); 646 647 switch (item->tag) { 648 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: 649 ret = open_collection(parser, data & 0xff); 650 break; 651 case HID_MAIN_ITEM_TAG_END_COLLECTION: 652 ret = close_collection(parser); 653 break; 654 case HID_MAIN_ITEM_TAG_INPUT: 655 ret = hid_add_field(parser, HID_INPUT_REPORT, data); 656 break; 657 case HID_MAIN_ITEM_TAG_OUTPUT: 658 ret = hid_add_field(parser, HID_OUTPUT_REPORT, data); 659 break; 660 case HID_MAIN_ITEM_TAG_FEATURE: 661 ret = hid_add_field(parser, HID_FEATURE_REPORT, data); 662 break; 663 default: 664 if (item->tag >= HID_MAIN_ITEM_TAG_RESERVED_MIN && 665 item->tag <= HID_MAIN_ITEM_TAG_RESERVED_MAX) 666 hid_warn_ratelimited(parser->device, "reserved main item tag 0x%x\n", item->tag); 667 else 668 hid_warn_ratelimited(parser->device, "unknown main item tag 0x%x\n", item->tag); 669 ret = 0; 670 } 671 672 memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */ 673 674 return ret; 675 } 676 677 /* 678 * Process a reserved item. 679 */ 680 681 static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item) 682 { 683 dbg_hid("reserved item type, tag 0x%x\n", item->tag); 684 return 0; 685 } 686 687 /* 688 * Free a report and all registered fields. The field->usage and 689 * field->value table's are allocated behind the field, so we need 690 * only to free(field) itself. 691 */ 692 693 static void hid_free_report(struct hid_report *report) 694 { 695 unsigned n; 696 697 kfree(report->field_entries); 698 699 for (n = 0; n < report->maxfield; n++) 700 kvfree(report->field[n]); 701 kfree(report); 702 } 703 704 /* 705 * Close report. This function returns the device 706 * state to the point prior to hid_open_report(). 707 */ 708 static void hid_close_report(struct hid_device *device) 709 { 710 unsigned i, j; 711 712 for (i = 0; i < HID_REPORT_TYPES; i++) { 713 struct hid_report_enum *report_enum = device->report_enum + i; 714 715 for (j = 0; j < HID_MAX_IDS; j++) { 716 struct hid_report *report = report_enum->report_id_hash[j]; 717 if (report) 718 hid_free_report(report); 719 } 720 memset(report_enum, 0, sizeof(*report_enum)); 721 INIT_LIST_HEAD(&report_enum->report_list); 722 } 723 724 /* 725 * If the HID driver had a rdesc_fixup() callback, dev->rdesc 726 * will be allocated by hid-core and needs to be freed. 727 * Otherwise, it is either equal to dev_rdesc or bpf_rdesc, in 728 * which cases it'll be freed later on device removal or destroy. 729 */ 730 if (device->rdesc != device->dev_rdesc && device->rdesc != device->bpf_rdesc) 731 kfree(device->rdesc); 732 device->rdesc = NULL; 733 device->rsize = 0; 734 735 kfree(device->collection); 736 device->collection = NULL; 737 device->collection_size = 0; 738 device->maxcollection = 0; 739 device->maxapplication = 0; 740 741 device->status &= ~HID_STAT_PARSED; 742 } 743 744 static inline void hid_free_bpf_rdesc(struct hid_device *hdev) 745 { 746 /* bpf_rdesc is either equal to dev_rdesc or allocated by call_hid_bpf_rdesc_fixup() */ 747 if (hdev->bpf_rdesc != hdev->dev_rdesc) 748 kfree(hdev->bpf_rdesc); 749 hdev->bpf_rdesc = NULL; 750 } 751 752 /* 753 * Free a device structure, all reports, and all fields. 754 */ 755 756 void hiddev_free(struct kref *ref) 757 { 758 struct hid_device *hid = container_of(ref, struct hid_device, ref); 759 760 hid_close_report(hid); 761 hid_free_bpf_rdesc(hid); 762 kfree(hid->dev_rdesc); 763 kfree(hid); 764 } 765 766 static void hid_device_release(struct device *dev) 767 { 768 struct hid_device *hid = to_hid_device(dev); 769 770 kref_put(&hid->ref, hiddev_free); 771 } 772 773 /* 774 * Fetch a report description item from the data stream. We support long 775 * items, though they are not used yet. 776 */ 777 778 static const u8 *fetch_item(const __u8 *start, const __u8 *end, struct hid_item *item) 779 { 780 u8 b; 781 782 if ((end - start) <= 0) 783 return NULL; 784 785 b = *start++; 786 787 item->type = (b >> 2) & 3; 788 item->tag = (b >> 4) & 15; 789 790 if (item->tag == HID_ITEM_TAG_LONG) { 791 792 item->format = HID_ITEM_FORMAT_LONG; 793 794 if ((end - start) < 2) 795 return NULL; 796 797 item->size = *start++; 798 item->tag = *start++; 799 800 if ((end - start) < item->size) 801 return NULL; 802 803 item->data.longdata = start; 804 start += item->size; 805 return start; 806 } 807 808 item->format = HID_ITEM_FORMAT_SHORT; 809 item->size = BIT(b & 3) >> 1; /* 0, 1, 2, 3 -> 0, 1, 2, 4 */ 810 811 if (end - start < item->size) 812 return NULL; 813 814 switch (item->size) { 815 case 0: 816 break; 817 818 case 1: 819 item->data.u8 = *start; 820 break; 821 822 case 2: 823 item->data.u16 = get_unaligned_le16(start); 824 break; 825 826 case 4: 827 item->data.u32 = get_unaligned_le32(start); 828 break; 829 } 830 831 return start + item->size; 832 } 833 834 static void hid_scan_input_usage(struct hid_parser *parser, u32 usage) 835 { 836 struct hid_device *hid = parser->device; 837 838 if (usage == HID_DG_CONTACTID) 839 hid->group = HID_GROUP_MULTITOUCH; 840 } 841 842 static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage) 843 { 844 if (usage == 0xff0000c5 && parser->global.report_count == 256 && 845 parser->global.report_size == 8) 846 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8; 847 848 if (usage == 0xff0000c6 && parser->global.report_count == 1 && 849 parser->global.report_size == 8) 850 parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8; 851 } 852 853 static void hid_scan_collection(struct hid_parser *parser, unsigned type) 854 { 855 struct hid_device *hid = parser->device; 856 int i; 857 858 if (((parser->global.usage_page << 16) == HID_UP_SENSOR) && 859 (type == HID_COLLECTION_PHYSICAL || 860 type == HID_COLLECTION_APPLICATION)) 861 hid->group = HID_GROUP_SENSOR_HUB; 862 863 if (hid->vendor == USB_VENDOR_ID_MICROSOFT && 864 hid->product == USB_DEVICE_ID_MS_POWER_COVER && 865 hid->group == HID_GROUP_MULTITOUCH) 866 hid->group = HID_GROUP_GENERIC; 867 868 if ((parser->global.usage_page << 16) == HID_UP_GENDESK) 869 for (i = 0; i < parser->local.usage_index; i++) 870 if (parser->local.usage[i] == HID_GD_POINTER) 871 parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER; 872 873 if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR) 874 parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC; 875 876 if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR) 877 for (i = 0; i < parser->local.usage_index; i++) 878 if (parser->local.usage[i] == 879 (HID_UP_GOOGLEVENDOR | 0x0001)) 880 parser->device->group = 881 HID_GROUP_VIVALDI; 882 } 883 884 static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) 885 { 886 __u32 data; 887 int i; 888 889 hid_concatenate_last_usage_page(parser); 890 891 data = item_udata(item); 892 893 switch (item->tag) { 894 case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: 895 hid_scan_collection(parser, data & 0xff); 896 break; 897 case HID_MAIN_ITEM_TAG_END_COLLECTION: 898 break; 899 case HID_MAIN_ITEM_TAG_INPUT: 900 /* ignore constant inputs, they will be ignored by hid-input */ 901 if (data & HID_MAIN_ITEM_CONSTANT) 902 break; 903 for (i = 0; i < parser->local.usage_index; i++) 904 hid_scan_input_usage(parser, parser->local.usage[i]); 905 break; 906 case HID_MAIN_ITEM_TAG_OUTPUT: 907 break; 908 case HID_MAIN_ITEM_TAG_FEATURE: 909 for (i = 0; i < parser->local.usage_index; i++) 910 hid_scan_feature_usage(parser, parser->local.usage[i]); 911 break; 912 } 913 914 /* Reset the local parser environment */ 915 memset(&parser->local, 0, sizeof(parser->local)); 916 917 return 0; 918 } 919 920 /* 921 * Scan a report descriptor before the device is added to the bus. 922 * Sets device groups and other properties that determine what driver 923 * to load. 924 */ 925 static int hid_scan_report(struct hid_device *hid) 926 { 927 struct hid_parser *parser; 928 struct hid_item item; 929 const __u8 *start = hid->dev_rdesc; 930 const __u8 *end = start + hid->dev_rsize; 931 static int (*dispatch_type[])(struct hid_parser *parser, 932 struct hid_item *item) = { 933 hid_scan_main, 934 hid_parser_global, 935 hid_parser_local, 936 hid_parser_reserved 937 }; 938 939 parser = vzalloc(sizeof(struct hid_parser)); 940 if (!parser) 941 return -ENOMEM; 942 943 parser->device = hid; 944 hid->group = HID_GROUP_GENERIC; 945 946 /* 947 * In case we are re-scanning after a BPF has been loaded, 948 * we need to use the bpf report descriptor, not the original one. 949 */ 950 if (hid->bpf_rdesc && hid->bpf_rsize) { 951 start = hid->bpf_rdesc; 952 end = start + hid->bpf_rsize; 953 } 954 955 /* 956 * The parsing is simpler than the one in hid_open_report() as we should 957 * be robust against hid errors. Those errors will be raised by 958 * hid_open_report() anyway. 959 */ 960 while ((start = fetch_item(start, end, &item)) != NULL) 961 dispatch_type[item.type](parser, &item); 962 963 /* 964 * Handle special flags set during scanning. 965 */ 966 if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) && 967 (hid->group == HID_GROUP_MULTITOUCH)) 968 hid->group = HID_GROUP_MULTITOUCH_WIN_8; 969 970 /* 971 * Vendor specific handlings 972 */ 973 switch (hid->vendor) { 974 case USB_VENDOR_ID_WACOM: 975 hid->group = HID_GROUP_WACOM; 976 break; 977 case USB_VENDOR_ID_SYNAPTICS: 978 if (hid->group == HID_GROUP_GENERIC) 979 if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC) 980 && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER)) 981 /* 982 * hid-rmi should take care of them, 983 * not hid-generic 984 */ 985 hid->group = HID_GROUP_RMI; 986 break; 987 } 988 989 kfree(parser->collection_stack); 990 vfree(parser); 991 return 0; 992 } 993 994 /** 995 * hid_parse_report - parse device report 996 * 997 * @hid: hid device 998 * @start: report start 999 * @size: report size 1000 * 1001 * Allocate the device report as read by the bus driver. This function should 1002 * only be called from parse() in ll drivers. 1003 */ 1004 int hid_parse_report(struct hid_device *hid, const __u8 *start, unsigned size) 1005 { 1006 hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL); 1007 if (!hid->dev_rdesc) 1008 return -ENOMEM; 1009 hid->dev_rsize = size; 1010 return 0; 1011 } 1012 EXPORT_SYMBOL_GPL(hid_parse_report); 1013 1014 static const char * const hid_report_names[] = { 1015 "HID_INPUT_REPORT", 1016 "HID_OUTPUT_REPORT", 1017 "HID_FEATURE_REPORT", 1018 }; 1019 /** 1020 * hid_validate_values - validate existing device report's value indexes 1021 * 1022 * @hid: hid device 1023 * @type: which report type to examine 1024 * @id: which report ID to examine (0 for first) 1025 * @field_index: which report field to examine 1026 * @report_counts: expected number of values 1027 * 1028 * Validate the number of values in a given field of a given report, after 1029 * parsing. 1030 */ 1031 struct hid_report *hid_validate_values(struct hid_device *hid, 1032 enum hid_report_type type, unsigned int id, 1033 unsigned int field_index, 1034 unsigned int report_counts) 1035 { 1036 struct hid_report *report; 1037 1038 if (type > HID_FEATURE_REPORT) { 1039 hid_err(hid, "invalid HID report type %u\n", type); 1040 return NULL; 1041 } 1042 1043 if (id >= HID_MAX_IDS) { 1044 hid_err(hid, "invalid HID report id %u\n", id); 1045 return NULL; 1046 } 1047 1048 /* 1049 * Explicitly not using hid_get_report() here since it depends on 1050 * ->numbered being checked, which may not always be the case when 1051 * drivers go to access report values. 1052 */ 1053 if (id == 0) { 1054 /* 1055 * Validating on id 0 means we should examine the first 1056 * report in the list. 1057 */ 1058 report = list_first_entry_or_null( 1059 &hid->report_enum[type].report_list, 1060 struct hid_report, list); 1061 } else { 1062 report = hid->report_enum[type].report_id_hash[id]; 1063 } 1064 if (!report) { 1065 hid_err(hid, "missing %s %u\n", hid_report_names[type], id); 1066 return NULL; 1067 } 1068 if (report->maxfield <= field_index) { 1069 hid_err(hid, "not enough fields in %s %u\n", 1070 hid_report_names[type], id); 1071 return NULL; 1072 } 1073 if (report->field[field_index]->report_count < report_counts) { 1074 hid_err(hid, "not enough values in %s %u field %u\n", 1075 hid_report_names[type], id, field_index); 1076 return NULL; 1077 } 1078 return report; 1079 } 1080 EXPORT_SYMBOL_GPL(hid_validate_values); 1081 1082 static int hid_calculate_multiplier(struct hid_device *hid, 1083 struct hid_field *multiplier) 1084 { 1085 int m; 1086 __s32 v = *multiplier->value; 1087 __s32 lmin = multiplier->logical_minimum; 1088 __s32 lmax = multiplier->logical_maximum; 1089 __s32 pmin = multiplier->physical_minimum; 1090 __s32 pmax = multiplier->physical_maximum; 1091 1092 /* 1093 * "Because OS implementations will generally divide the control's 1094 * reported count by the Effective Resolution Multiplier, designers 1095 * should take care not to establish a potential Effective 1096 * Resolution Multiplier of zero." 1097 * HID Usage Table, v1.12, Section 4.3.1, p31 1098 */ 1099 if (lmax - lmin == 0) 1100 return 1; 1101 /* 1102 * Handling the unit exponent is left as an exercise to whoever 1103 * finds a device where that exponent is not 0. 1104 */ 1105 m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin); 1106 if (unlikely(multiplier->unit_exponent != 0)) { 1107 hid_warn(hid, 1108 "unsupported Resolution Multiplier unit exponent %d\n", 1109 multiplier->unit_exponent); 1110 } 1111 1112 /* There are no devices with an effective multiplier > 255 */ 1113 if (unlikely(m == 0 || m > 255 || m < -255)) { 1114 hid_warn(hid, "unsupported Resolution Multiplier %d\n", m); 1115 m = 1; 1116 } 1117 1118 return m; 1119 } 1120 1121 static void hid_apply_multiplier_to_field(struct hid_device *hid, 1122 struct hid_field *field, 1123 struct hid_collection *multiplier_collection, 1124 int effective_multiplier) 1125 { 1126 struct hid_collection *collection; 1127 struct hid_usage *usage; 1128 int i; 1129 1130 /* 1131 * If multiplier_collection is NULL, the multiplier applies 1132 * to all fields in the report. 1133 * Otherwise, it is the Logical Collection the multiplier applies to 1134 * but our field may be in a subcollection of that collection. 1135 */ 1136 for (i = 0; i < field->maxusage; i++) { 1137 usage = &field->usage[i]; 1138 1139 collection = &hid->collection[usage->collection_index]; 1140 while (collection->parent_idx != -1 && 1141 collection != multiplier_collection) 1142 collection = &hid->collection[collection->parent_idx]; 1143 1144 if (collection->parent_idx != -1 || 1145 multiplier_collection == NULL) 1146 usage->resolution_multiplier = effective_multiplier; 1147 1148 } 1149 } 1150 1151 static void hid_apply_multiplier(struct hid_device *hid, 1152 struct hid_field *multiplier) 1153 { 1154 struct hid_report_enum *rep_enum; 1155 struct hid_report *rep; 1156 struct hid_field *field; 1157 struct hid_collection *multiplier_collection; 1158 int effective_multiplier; 1159 int i; 1160 1161 /* 1162 * "The Resolution Multiplier control must be contained in the same 1163 * Logical Collection as the control(s) to which it is to be applied. 1164 * If no Resolution Multiplier is defined, then the Resolution 1165 * Multiplier defaults to 1. If more than one control exists in a 1166 * Logical Collection, the Resolution Multiplier is associated with 1167 * all controls in the collection. If no Logical Collection is 1168 * defined, the Resolution Multiplier is associated with all 1169 * controls in the report." 1170 * HID Usage Table, v1.12, Section 4.3.1, p30 1171 * 1172 * Thus, search from the current collection upwards until we find a 1173 * logical collection. Then search all fields for that same parent 1174 * collection. Those are the fields the multiplier applies to. 1175 * 1176 * If we have more than one multiplier, it will overwrite the 1177 * applicable fields later. 1178 */ 1179 multiplier_collection = &hid->collection[multiplier->usage->collection_index]; 1180 while (multiplier_collection->parent_idx != -1 && 1181 multiplier_collection->type != HID_COLLECTION_LOGICAL) 1182 multiplier_collection = &hid->collection[multiplier_collection->parent_idx]; 1183 if (multiplier_collection->type != HID_COLLECTION_LOGICAL) 1184 multiplier_collection = NULL; 1185 1186 effective_multiplier = hid_calculate_multiplier(hid, multiplier); 1187 1188 rep_enum = &hid->report_enum[HID_INPUT_REPORT]; 1189 list_for_each_entry(rep, &rep_enum->report_list, list) { 1190 for (i = 0; i < rep->maxfield; i++) { 1191 field = rep->field[i]; 1192 hid_apply_multiplier_to_field(hid, field, 1193 multiplier_collection, 1194 effective_multiplier); 1195 } 1196 } 1197 } 1198 1199 /* 1200 * hid_setup_resolution_multiplier - set up all resolution multipliers 1201 * 1202 * @device: hid device 1203 * 1204 * Search for all Resolution Multiplier Feature Reports and apply their 1205 * value to all matching Input items. This only updates the internal struct 1206 * fields. 1207 * 1208 * The Resolution Multiplier is applied by the hardware. If the multiplier 1209 * is anything other than 1, the hardware will send pre-multiplied events 1210 * so that the same physical interaction generates an accumulated 1211 * accumulated_value = value * * multiplier 1212 * This may be achieved by sending 1213 * - "value * multiplier" for each event, or 1214 * - "value" but "multiplier" times as frequently, or 1215 * - a combination of the above 1216 * The only guarantee is that the same physical interaction always generates 1217 * an accumulated 'value * multiplier'. 1218 * 1219 * This function must be called before any event processing and after 1220 * any SetRequest to the Resolution Multiplier. 1221 */ 1222 void hid_setup_resolution_multiplier(struct hid_device *hid) 1223 { 1224 struct hid_report_enum *rep_enum; 1225 struct hid_report *rep; 1226 struct hid_usage *usage; 1227 int i, j; 1228 1229 rep_enum = &hid->report_enum[HID_FEATURE_REPORT]; 1230 list_for_each_entry(rep, &rep_enum->report_list, list) { 1231 for (i = 0; i < rep->maxfield; i++) { 1232 /* Ignore if report count is out of bounds. */ 1233 if (rep->field[i]->report_count < 1) 1234 continue; 1235 1236 for (j = 0; j < rep->field[i]->maxusage; j++) { 1237 usage = &rep->field[i]->usage[j]; 1238 if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER) 1239 hid_apply_multiplier(hid, 1240 rep->field[i]); 1241 } 1242 } 1243 } 1244 } 1245 EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier); 1246 1247 /** 1248 * hid_open_report - open a driver-specific device report 1249 * 1250 * @device: hid device 1251 * 1252 * Parse a report description into a hid_device structure. Reports are 1253 * enumerated, fields are attached to these reports. 1254 * 0 returned on success, otherwise nonzero error value. 1255 * 1256 * This function (or the equivalent hid_parse() macro) should only be 1257 * called from probe() in drivers, before starting the device. 1258 */ 1259 int hid_open_report(struct hid_device *device) 1260 { 1261 struct hid_parser *parser; 1262 struct hid_item item; 1263 unsigned int size; 1264 const __u8 *start; 1265 const __u8 *end; 1266 const __u8 *next; 1267 int ret; 1268 int i; 1269 static int (*dispatch_type[])(struct hid_parser *parser, 1270 struct hid_item *item) = { 1271 hid_parser_main, 1272 hid_parser_global, 1273 hid_parser_local, 1274 hid_parser_reserved 1275 }; 1276 1277 if (WARN_ON(device->status & HID_STAT_PARSED)) 1278 return -EBUSY; 1279 1280 start = device->bpf_rdesc; 1281 if (WARN_ON(!start)) 1282 return -ENODEV; 1283 size = device->bpf_rsize; 1284 1285 if (device->driver->report_fixup) { 1286 /* 1287 * device->driver->report_fixup() needs to work 1288 * on a copy of our report descriptor so it can 1289 * change it. 1290 */ 1291 __u8 *buf = kmemdup(start, size, GFP_KERNEL); 1292 1293 if (buf == NULL) 1294 return -ENOMEM; 1295 1296 start = device->driver->report_fixup(device, buf, &size); 1297 1298 /* 1299 * The second kmemdup is required in case report_fixup() returns 1300 * a static read-only memory, but we have no idea if that memory 1301 * needs to be cleaned up or not at the end. 1302 */ 1303 start = kmemdup(start, size, GFP_KERNEL); 1304 kfree(buf); 1305 if (start == NULL) 1306 return -ENOMEM; 1307 } 1308 1309 device->rdesc = start; 1310 device->rsize = size; 1311 1312 parser = vzalloc(sizeof(struct hid_parser)); 1313 if (!parser) { 1314 ret = -ENOMEM; 1315 goto alloc_err; 1316 } 1317 1318 parser->device = device; 1319 1320 end = start + size; 1321 1322 device->collection = kzalloc_objs(struct hid_collection, 1323 HID_DEFAULT_NUM_COLLECTIONS, 1324 GFP_KERNEL); 1325 if (!device->collection) { 1326 ret = -ENOMEM; 1327 goto err; 1328 } 1329 device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; 1330 for (i = 0; i < HID_DEFAULT_NUM_COLLECTIONS; i++) 1331 device->collection[i].parent_idx = -1; 1332 1333 ret = -EINVAL; 1334 while ((next = fetch_item(start, end, &item)) != NULL) { 1335 start = next; 1336 1337 if (item.format != HID_ITEM_FORMAT_SHORT) { 1338 hid_err(device, "unexpected long global item\n"); 1339 goto err; 1340 } 1341 1342 if (dispatch_type[item.type](parser, &item)) { 1343 hid_err(device, "item %u %u %u %u parsing failed\n", 1344 item.format, (unsigned)item.size, 1345 (unsigned)item.type, (unsigned)item.tag); 1346 goto err; 1347 } 1348 1349 if (start == end) { 1350 if (parser->collection_stack_ptr) { 1351 hid_err(device, "unbalanced collection at end of report description\n"); 1352 goto err; 1353 } 1354 if (parser->local.delimiter_depth) { 1355 hid_err(device, "unbalanced delimiter at end of report description\n"); 1356 goto err; 1357 } 1358 1359 /* 1360 * fetch initial values in case the device's 1361 * default multiplier isn't the recommended 1 1362 */ 1363 hid_setup_resolution_multiplier(device); 1364 1365 kfree(parser->collection_stack); 1366 vfree(parser); 1367 device->status |= HID_STAT_PARSED; 1368 1369 return 0; 1370 } 1371 } 1372 1373 hid_err(device, "item fetching failed at offset %u/%u\n", 1374 size - (unsigned int)(end - start), size); 1375 err: 1376 kfree(parser->collection_stack); 1377 alloc_err: 1378 vfree(parser); 1379 hid_close_report(device); 1380 return ret; 1381 } 1382 EXPORT_SYMBOL_GPL(hid_open_report); 1383 1384 /* 1385 * Extract/implement a data field from/to a little endian report (bit array). 1386 * 1387 * Code sort-of follows HID spec: 1388 * http://www.usb.org/developers/hidpage/HID1_11.pdf 1389 * 1390 * While the USB HID spec allows unlimited length bit fields in "report 1391 * descriptors", most devices never use more than 16 bits. 1392 * One model of UPS is claimed to report "LINEV" as a 32-bit field. 1393 * Search linux-kernel and linux-usb-devel archives for "hid-core extract". 1394 */ 1395 1396 static u32 __extract(u8 *report, unsigned offset, int n) 1397 { 1398 unsigned int idx = offset / 8; 1399 unsigned int bit_nr = 0; 1400 unsigned int bit_shift = offset % 8; 1401 int bits_to_copy = 8 - bit_shift; 1402 u32 value = 0; 1403 u32 mask = n < 32 ? (1U << n) - 1 : ~0U; 1404 1405 while (n > 0) { 1406 value |= ((u32)report[idx] >> bit_shift) << bit_nr; 1407 n -= bits_to_copy; 1408 bit_nr += bits_to_copy; 1409 bits_to_copy = 8; 1410 bit_shift = 0; 1411 idx++; 1412 } 1413 1414 return value & mask; 1415 } 1416 1417 u32 hid_field_extract(const struct hid_device *hid, u8 *report, 1418 unsigned offset, unsigned n) 1419 { 1420 if (n > 32) { 1421 hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n", 1422 __func__, n, current->comm); 1423 n = 32; 1424 } 1425 1426 return __extract(report, offset, n); 1427 } 1428 EXPORT_SYMBOL_GPL(hid_field_extract); 1429 1430 /* 1431 * "implement" : set bits in a little endian bit stream. 1432 * Same concepts as "extract" (see comments above). 1433 * The data mangled in the bit stream remains in little endian 1434 * order the whole time. It make more sense to talk about 1435 * endianness of register values by considering a register 1436 * a "cached" copy of the little endian bit stream. 1437 */ 1438 1439 static void __implement(u8 *report, unsigned offset, int n, u32 value) 1440 { 1441 unsigned int idx = offset / 8; 1442 unsigned int bit_shift = offset % 8; 1443 int bits_to_set = 8 - bit_shift; 1444 1445 while (n - bits_to_set >= 0) { 1446 report[idx] &= ~(0xff << bit_shift); 1447 report[idx] |= value << bit_shift; 1448 value >>= bits_to_set; 1449 n -= bits_to_set; 1450 bits_to_set = 8; 1451 bit_shift = 0; 1452 idx++; 1453 } 1454 1455 /* last nibble */ 1456 if (n) { 1457 u8 bit_mask = ((1U << n) - 1); 1458 report[idx] &= ~(bit_mask << bit_shift); 1459 report[idx] |= value << bit_shift; 1460 } 1461 } 1462 1463 static void implement(const struct hid_device *hid, u8 *report, 1464 unsigned offset, unsigned n, u32 value) 1465 { 1466 if (unlikely(n > 32)) { 1467 hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n", 1468 __func__, n, current->comm); 1469 n = 32; 1470 } else if (n < 32) { 1471 u32 m = (1U << n) - 1; 1472 1473 if (unlikely(value > m)) { 1474 hid_warn(hid, 1475 "%s() called with too large value %d (n: %d)! (%s)\n", 1476 __func__, value, n, current->comm); 1477 value &= m; 1478 } 1479 } 1480 1481 __implement(report, offset, n, value); 1482 } 1483 1484 /* 1485 * Search an array for a value. 1486 */ 1487 1488 static int search(__s32 *array, __s32 value, unsigned n) 1489 { 1490 while (n--) { 1491 if (*array++ == value) 1492 return 0; 1493 } 1494 return -1; 1495 } 1496 1497 /** 1498 * hid_match_report - check if driver's raw_event should be called 1499 * 1500 * @hid: hid device 1501 * @report: hid report to match against 1502 * 1503 * compare hid->driver->report_table->report_type to report->type 1504 */ 1505 static int hid_match_report(struct hid_device *hid, struct hid_report *report) 1506 { 1507 const struct hid_report_id *id = hid->driver->report_table; 1508 1509 if (!id) /* NULL means all */ 1510 return 1; 1511 1512 for (; id->report_type != HID_TERMINATOR; id++) 1513 if (id->report_type == HID_ANY_ID || 1514 id->report_type == report->type) 1515 return 1; 1516 return 0; 1517 } 1518 1519 /** 1520 * hid_match_usage - check if driver's event should be called 1521 * 1522 * @hid: hid device 1523 * @usage: usage to match against 1524 * 1525 * compare hid->driver->usage_table->usage_{type,code} to 1526 * usage->usage_{type,code} 1527 */ 1528 static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage) 1529 { 1530 const struct hid_usage_id *id = hid->driver->usage_table; 1531 1532 if (!id) /* NULL means all */ 1533 return 1; 1534 1535 for (; id->usage_type != HID_ANY_ID - 1; id++) 1536 if ((id->usage_hid == HID_ANY_ID || 1537 id->usage_hid == usage->hid) && 1538 (id->usage_type == HID_ANY_ID || 1539 id->usage_type == usage->type) && 1540 (id->usage_code == HID_ANY_ID || 1541 id->usage_code == usage->code)) 1542 return 1; 1543 return 0; 1544 } 1545 1546 static void hid_process_event(struct hid_device *hid, struct hid_field *field, 1547 struct hid_usage *usage, __s32 value, int interrupt) 1548 { 1549 struct hid_driver *hdrv = hid->driver; 1550 int ret; 1551 1552 if (!list_empty(&hid->debug_list)) 1553 hid_dump_input(hid, usage, value); 1554 1555 if (hdrv && hdrv->event && hid_match_usage(hid, usage)) { 1556 ret = hdrv->event(hid, field, usage, value); 1557 if (ret != 0) { 1558 if (ret < 0) 1559 hid_err(hid, "%s's event failed with %d\n", 1560 hdrv->name, ret); 1561 return; 1562 } 1563 } 1564 1565 if (hid->claimed & HID_CLAIMED_INPUT) 1566 hidinput_hid_event(hid, field, usage, value); 1567 if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) 1568 hid->hiddev_hid_event(hid, field, usage, value); 1569 } 1570 1571 /* 1572 * Checks if the given value is valid within this field 1573 */ 1574 static inline int hid_array_value_is_valid(struct hid_field *field, 1575 __s32 value) 1576 { 1577 __s32 min = field->logical_minimum; 1578 1579 /* 1580 * Value needs to be between logical min and max, and 1581 * (value - min) is used as an index in the usage array. 1582 * This array is of size field->maxusage 1583 */ 1584 return value >= min && 1585 value <= field->logical_maximum && 1586 value - min < field->maxusage; 1587 } 1588 1589 /* 1590 * Fetch the field from the data. The field content is stored for next 1591 * report processing (we do differential reporting to the layer). 1592 */ 1593 static void hid_input_fetch_field(struct hid_device *hid, 1594 struct hid_field *field, 1595 __u8 *data) 1596 { 1597 unsigned n; 1598 unsigned count = field->report_count; 1599 unsigned offset = field->report_offset; 1600 unsigned size = field->report_size; 1601 __s32 min = field->logical_minimum; 1602 __s32 *value; 1603 1604 value = field->new_value; 1605 memset(value, 0, count * sizeof(__s32)); 1606 field->ignored = false; 1607 1608 for (n = 0; n < count; n++) { 1609 1610 value[n] = min < 0 ? 1611 snto32(hid_field_extract(hid, data, offset + n * size, 1612 size), size) : 1613 hid_field_extract(hid, data, offset + n * size, size); 1614 1615 /* Ignore report if ErrorRollOver */ 1616 if (!(field->flags & HID_MAIN_ITEM_VARIABLE) && 1617 hid_array_value_is_valid(field, value[n]) && 1618 field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) { 1619 field->ignored = true; 1620 return; 1621 } 1622 } 1623 } 1624 1625 /* 1626 * Process a received variable field. 1627 */ 1628 1629 static void hid_input_var_field(struct hid_device *hid, 1630 struct hid_field *field, 1631 int interrupt) 1632 { 1633 unsigned int count = field->report_count; 1634 __s32 *value = field->new_value; 1635 unsigned int n; 1636 1637 for (n = 0; n < count; n++) 1638 hid_process_event(hid, 1639 field, 1640 &field->usage[n], 1641 value[n], 1642 interrupt); 1643 1644 memcpy(field->value, value, count * sizeof(__s32)); 1645 } 1646 1647 /* 1648 * Process a received array field. The field content is stored for 1649 * next report processing (we do differential reporting to the layer). 1650 */ 1651 1652 static void hid_input_array_field(struct hid_device *hid, 1653 struct hid_field *field, 1654 int interrupt) 1655 { 1656 unsigned int n; 1657 unsigned int count = field->report_count; 1658 __s32 min = field->logical_minimum; 1659 __s32 *value; 1660 1661 value = field->new_value; 1662 1663 /* ErrorRollOver */ 1664 if (field->ignored) 1665 return; 1666 1667 for (n = 0; n < count; n++) { 1668 if (hid_array_value_is_valid(field, field->value[n]) && 1669 search(value, field->value[n], count)) 1670 hid_process_event(hid, 1671 field, 1672 &field->usage[field->value[n] - min], 1673 0, 1674 interrupt); 1675 1676 if (hid_array_value_is_valid(field, value[n]) && 1677 search(field->value, value[n], count)) 1678 hid_process_event(hid, 1679 field, 1680 &field->usage[value[n] - min], 1681 1, 1682 interrupt); 1683 } 1684 1685 memcpy(field->value, value, count * sizeof(__s32)); 1686 } 1687 1688 /* 1689 * Analyse a received report, and fetch the data from it. The field 1690 * content is stored for next report processing (we do differential 1691 * reporting to the layer). 1692 */ 1693 static void hid_process_report(struct hid_device *hid, 1694 struct hid_report *report, 1695 __u8 *data, 1696 int interrupt) 1697 { 1698 unsigned int a; 1699 struct hid_field_entry *entry; 1700 struct hid_field *field; 1701 1702 /* first retrieve all incoming values in data */ 1703 for (a = 0; a < report->maxfield; a++) 1704 hid_input_fetch_field(hid, report->field[a], data); 1705 1706 if (!list_empty(&report->field_entry_list)) { 1707 /* INPUT_REPORT, we have a priority list of fields */ 1708 list_for_each_entry(entry, 1709 &report->field_entry_list, 1710 list) { 1711 field = entry->field; 1712 1713 if (field->flags & HID_MAIN_ITEM_VARIABLE) 1714 hid_process_event(hid, 1715 field, 1716 &field->usage[entry->index], 1717 field->new_value[entry->index], 1718 interrupt); 1719 else 1720 hid_input_array_field(hid, field, interrupt); 1721 } 1722 1723 /* we need to do the memcpy at the end for var items */ 1724 for (a = 0; a < report->maxfield; a++) { 1725 field = report->field[a]; 1726 1727 if (field->flags & HID_MAIN_ITEM_VARIABLE) 1728 memcpy(field->value, field->new_value, 1729 field->report_count * sizeof(__s32)); 1730 } 1731 } else { 1732 /* FEATURE_REPORT, regular processing */ 1733 for (a = 0; a < report->maxfield; a++) { 1734 field = report->field[a]; 1735 1736 if (field->flags & HID_MAIN_ITEM_VARIABLE) 1737 hid_input_var_field(hid, field, interrupt); 1738 else 1739 hid_input_array_field(hid, field, interrupt); 1740 } 1741 } 1742 } 1743 1744 /* 1745 * Insert a given usage_index in a field in the list 1746 * of processed usages in the report. 1747 * 1748 * The elements of lower priority score are processed 1749 * first. 1750 */ 1751 static void __hid_insert_field_entry(struct hid_device *hid, 1752 struct hid_report *report, 1753 struct hid_field_entry *entry, 1754 struct hid_field *field, 1755 unsigned int usage_index) 1756 { 1757 struct hid_field_entry *next; 1758 1759 entry->field = field; 1760 entry->index = usage_index; 1761 entry->priority = field->usages_priorities[usage_index]; 1762 1763 /* insert the element at the correct position */ 1764 list_for_each_entry(next, 1765 &report->field_entry_list, 1766 list) { 1767 /* 1768 * the priority of our element is strictly higher 1769 * than the next one, insert it before 1770 */ 1771 if (entry->priority > next->priority) { 1772 list_add_tail(&entry->list, &next->list); 1773 return; 1774 } 1775 } 1776 1777 /* lowest priority score: insert at the end */ 1778 list_add_tail(&entry->list, &report->field_entry_list); 1779 } 1780 1781 static void hid_report_process_ordering(struct hid_device *hid, 1782 struct hid_report *report) 1783 { 1784 struct hid_field *field; 1785 struct hid_field_entry *entries; 1786 unsigned int a, u, usages; 1787 unsigned int count = 0; 1788 1789 /* count the number of individual fields in the report */ 1790 for (a = 0; a < report->maxfield; a++) { 1791 field = report->field[a]; 1792 1793 if (field->flags & HID_MAIN_ITEM_VARIABLE) 1794 count += field->report_count; 1795 else 1796 count++; 1797 } 1798 1799 /* allocate the memory to process the fields */ 1800 entries = kzalloc_objs(*entries, count, GFP_KERNEL); 1801 if (!entries) 1802 return; 1803 1804 report->field_entries = entries; 1805 1806 /* 1807 * walk through all fields in the report and 1808 * store them by priority order in report->field_entry_list 1809 * 1810 * - Var elements are individualized (field + usage_index) 1811 * - Arrays are taken as one, we can not chose an order for them 1812 */ 1813 usages = 0; 1814 for (a = 0; a < report->maxfield; a++) { 1815 field = report->field[a]; 1816 1817 if (field->flags & HID_MAIN_ITEM_VARIABLE) { 1818 for (u = 0; u < field->report_count; u++) { 1819 __hid_insert_field_entry(hid, report, 1820 &entries[usages], 1821 field, u); 1822 usages++; 1823 } 1824 } else { 1825 __hid_insert_field_entry(hid, report, &entries[usages], 1826 field, 0); 1827 usages++; 1828 } 1829 } 1830 } 1831 1832 static void hid_process_ordering(struct hid_device *hid) 1833 { 1834 struct hid_report *report; 1835 struct hid_report_enum *report_enum = &hid->report_enum[HID_INPUT_REPORT]; 1836 1837 list_for_each_entry(report, &report_enum->report_list, list) 1838 hid_report_process_ordering(hid, report); 1839 } 1840 1841 /* 1842 * Output the field into the report. 1843 */ 1844 1845 static void hid_output_field(const struct hid_device *hid, 1846 struct hid_field *field, __u8 *data) 1847 { 1848 unsigned count = field->report_count; 1849 unsigned offset = field->report_offset; 1850 unsigned size = field->report_size; 1851 unsigned n; 1852 1853 for (n = 0; n < count; n++) { 1854 if (field->logical_minimum < 0) /* signed values */ 1855 implement(hid, data, offset + n * size, size, 1856 s32ton(field->value[n], size)); 1857 else /* unsigned values */ 1858 implement(hid, data, offset + n * size, size, 1859 field->value[n]); 1860 } 1861 } 1862 1863 /* 1864 * Compute the size of a report. 1865 */ 1866 static size_t hid_compute_report_size(struct hid_report *report) 1867 { 1868 if (report->size) 1869 return ((report->size - 1) >> 3) + 1; 1870 1871 return 0; 1872 } 1873 1874 /* 1875 * Create a report. 'data' has to be allocated using 1876 * hid_alloc_report_buf() so that it has proper size. 1877 */ 1878 1879 void hid_output_report(struct hid_report *report, __u8 *data) 1880 { 1881 unsigned n; 1882 1883 if (report->id > 0) 1884 *data++ = report->id; 1885 1886 memset(data, 0, hid_compute_report_size(report)); 1887 for (n = 0; n < report->maxfield; n++) 1888 hid_output_field(report->device, report->field[n], data); 1889 } 1890 EXPORT_SYMBOL_GPL(hid_output_report); 1891 1892 /* 1893 * Allocator for buffer that is going to be passed to hid_output_report() 1894 */ 1895 u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags) 1896 { 1897 /* 1898 * 7 extra bytes are necessary to achieve proper functionality 1899 * of implement() working on 8 byte chunks 1900 * 1 extra byte for the report ID if it is null (not used) so 1901 * we can reserve that extra byte in the first position of the buffer 1902 * when sending it to .raw_request() 1903 */ 1904 1905 u32 len = hid_report_len(report) + 7 + (report->id == 0); 1906 1907 return kzalloc(len, flags); 1908 } 1909 EXPORT_SYMBOL_GPL(hid_alloc_report_buf); 1910 1911 /* 1912 * Set a field value. The report this field belongs to has to be 1913 * created and transferred to the device, to set this value in the 1914 * device. 1915 */ 1916 1917 int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) 1918 { 1919 unsigned size; 1920 1921 if (!field) 1922 return -1; 1923 1924 size = field->report_size; 1925 1926 hid_dump_input(field->report->device, field->usage + offset, value); 1927 1928 if (offset >= field->report_count) { 1929 hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n", 1930 offset, field->report_count); 1931 return -1; 1932 } 1933 if (field->logical_minimum < 0) { 1934 if (value != snto32(s32ton(value, size), size)) { 1935 hid_err(field->report->device, "value %d is out of range\n", value); 1936 return -1; 1937 } 1938 } 1939 field->value[offset] = value; 1940 return 0; 1941 } 1942 EXPORT_SYMBOL_GPL(hid_set_field); 1943 1944 struct hid_field *hid_find_field(struct hid_device *hdev, unsigned int report_type, 1945 unsigned int application, unsigned int usage) 1946 { 1947 struct list_head *report_list = &hdev->report_enum[report_type].report_list; 1948 struct hid_report *report; 1949 int i, j; 1950 1951 list_for_each_entry(report, report_list, list) { 1952 if (report->application != application) 1953 continue; 1954 1955 for (i = 0; i < report->maxfield; i++) { 1956 struct hid_field *field = report->field[i]; 1957 1958 for (j = 0; j < field->maxusage; j++) { 1959 if (field->usage[j].hid == usage) 1960 return field; 1961 } 1962 } 1963 } 1964 1965 return NULL; 1966 } 1967 EXPORT_SYMBOL_GPL(hid_find_field); 1968 1969 static struct hid_report *hid_get_report(struct hid_report_enum *report_enum, 1970 const u8 *data) 1971 { 1972 struct hid_report *report; 1973 unsigned int n = 0; /* Normally report number is 0 */ 1974 1975 /* Device uses numbered reports, data[0] is report number */ 1976 if (report_enum->numbered) 1977 n = *data; 1978 1979 report = report_enum->report_id_hash[n]; 1980 if (report == NULL) 1981 dbg_hid("undefined report_id %u received\n", n); 1982 1983 return report; 1984 } 1985 1986 /* 1987 * Implement a generic .request() callback, using .raw_request() 1988 * DO NOT USE in hid drivers directly, but through hid_hw_request instead. 1989 */ 1990 int __hid_request(struct hid_device *hid, struct hid_report *report, 1991 enum hid_class_request reqtype) 1992 { 1993 char *buf, *data_buf; 1994 int ret; 1995 u32 len; 1996 1997 buf = hid_alloc_report_buf(report, GFP_KERNEL); 1998 if (!buf) 1999 return -ENOMEM; 2000 2001 data_buf = buf; 2002 len = hid_report_len(report); 2003 2004 if (report->id == 0) { 2005 /* reserve the first byte for the report ID */ 2006 data_buf++; 2007 len++; 2008 } 2009 2010 if (reqtype == HID_REQ_SET_REPORT) 2011 hid_output_report(report, data_buf); 2012 2013 ret = hid_hw_raw_request(hid, report->id, buf, len, report->type, reqtype); 2014 if (ret < 0) { 2015 dbg_hid("unable to complete request: %d\n", ret); 2016 goto out; 2017 } 2018 2019 if (reqtype == HID_REQ_GET_REPORT) 2020 hid_input_report(hid, report->type, buf, ret, 0); 2021 2022 ret = 0; 2023 2024 out: 2025 kfree(buf); 2026 return ret; 2027 } 2028 EXPORT_SYMBOL_GPL(__hid_request); 2029 2030 int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, 2031 int interrupt) 2032 { 2033 struct hid_report_enum *report_enum = hid->report_enum + type; 2034 struct hid_report *report; 2035 struct hid_driver *hdrv; 2036 int max_buffer_size = HID_MAX_BUFFER_SIZE; 2037 u32 rsize, csize = size; 2038 u8 *cdata = data; 2039 int ret = 0; 2040 2041 report = hid_get_report(report_enum, data); 2042 if (!report) 2043 goto out; 2044 2045 if (report_enum->numbered) { 2046 cdata++; 2047 csize--; 2048 } 2049 2050 rsize = hid_compute_report_size(report); 2051 2052 if (hid->ll_driver->max_buffer_size) 2053 max_buffer_size = hid->ll_driver->max_buffer_size; 2054 2055 if (report_enum->numbered && rsize >= max_buffer_size) 2056 rsize = max_buffer_size - 1; 2057 else if (rsize > max_buffer_size) 2058 rsize = max_buffer_size; 2059 2060 if (csize < rsize) { 2061 dbg_hid("report %d is too short, (%d < %d)\n", report->id, 2062 csize, rsize); 2063 memset(cdata + csize, 0, rsize - csize); 2064 } 2065 2066 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) 2067 hid->hiddev_report_event(hid, report); 2068 if (hid->claimed & HID_CLAIMED_HIDRAW) { 2069 ret = hidraw_report_event(hid, data, size); 2070 if (ret) 2071 goto out; 2072 } 2073 2074 if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) { 2075 hid_process_report(hid, report, cdata, interrupt); 2076 hdrv = hid->driver; 2077 if (hdrv && hdrv->report) 2078 hdrv->report(hid, report); 2079 } 2080 2081 if (hid->claimed & HID_CLAIMED_INPUT) 2082 hidinput_report_event(hid, report); 2083 out: 2084 return ret; 2085 } 2086 EXPORT_SYMBOL_GPL(hid_report_raw_event); 2087 2088 2089 static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, 2090 u8 *data, u32 size, int interrupt, u64 source, bool from_bpf, 2091 bool lock_already_taken) 2092 { 2093 struct hid_report_enum *report_enum; 2094 struct hid_driver *hdrv; 2095 struct hid_report *report; 2096 int ret = 0; 2097 2098 if (!hid) 2099 return -ENODEV; 2100 2101 ret = down_trylock(&hid->driver_input_lock); 2102 if (lock_already_taken && !ret) { 2103 up(&hid->driver_input_lock); 2104 return -EINVAL; 2105 } else if (!lock_already_taken && ret) { 2106 return -EBUSY; 2107 } 2108 2109 if (!hid->driver) { 2110 ret = -ENODEV; 2111 goto unlock; 2112 } 2113 report_enum = hid->report_enum + type; 2114 hdrv = hid->driver; 2115 2116 data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt, source, from_bpf); 2117 if (IS_ERR(data)) { 2118 ret = PTR_ERR(data); 2119 goto unlock; 2120 } 2121 2122 if (!size) { 2123 dbg_hid("empty report\n"); 2124 ret = -1; 2125 goto unlock; 2126 } 2127 2128 /* Avoid unnecessary overhead if debugfs is disabled */ 2129 if (!list_empty(&hid->debug_list)) 2130 hid_dump_report(hid, type, data, size); 2131 2132 report = hid_get_report(report_enum, data); 2133 2134 if (!report) { 2135 ret = -1; 2136 goto unlock; 2137 } 2138 2139 if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) { 2140 ret = hdrv->raw_event(hid, report, data, size); 2141 if (ret < 0) 2142 goto unlock; 2143 } 2144 2145 ret = hid_report_raw_event(hid, type, data, size, interrupt); 2146 2147 unlock: 2148 if (!lock_already_taken) 2149 up(&hid->driver_input_lock); 2150 return ret; 2151 } 2152 2153 /** 2154 * hid_input_report - report data from lower layer (usb, bt...) 2155 * 2156 * @hid: hid device 2157 * @type: HID report type (HID_*_REPORT) 2158 * @data: report contents 2159 * @size: size of data parameter 2160 * @interrupt: distinguish between interrupt and control transfers 2161 * 2162 * This is data entry for lower layers. 2163 */ 2164 int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, 2165 int interrupt) 2166 { 2167 return __hid_input_report(hid, type, data, size, interrupt, 0, 2168 false, /* from_bpf */ 2169 false /* lock_already_taken */); 2170 } 2171 EXPORT_SYMBOL_GPL(hid_input_report); 2172 2173 bool hid_match_one_id(const struct hid_device *hdev, 2174 const struct hid_device_id *id) 2175 { 2176 return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) && 2177 (id->group == HID_GROUP_ANY || id->group == hdev->group) && 2178 (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) && 2179 (id->product == HID_ANY_ID || id->product == hdev->product); 2180 } 2181 2182 const struct hid_device_id *hid_match_id(const struct hid_device *hdev, 2183 const struct hid_device_id *id) 2184 { 2185 for (; id->bus; id++) 2186 if (hid_match_one_id(hdev, id)) 2187 return id; 2188 2189 return NULL; 2190 } 2191 EXPORT_SYMBOL_GPL(hid_match_id); 2192 2193 static const struct hid_device_id hid_hiddev_list[] = { 2194 { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) }, 2195 { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) }, 2196 { } 2197 }; 2198 2199 static bool hid_hiddev(struct hid_device *hdev) 2200 { 2201 return !!hid_match_id(hdev, hid_hiddev_list); 2202 } 2203 2204 2205 static ssize_t 2206 report_descriptor_read(struct file *filp, struct kobject *kobj, 2207 const struct bin_attribute *attr, 2208 char *buf, loff_t off, size_t count) 2209 { 2210 struct device *dev = kobj_to_dev(kobj); 2211 struct hid_device *hdev = to_hid_device(dev); 2212 2213 if (off >= hdev->rsize) 2214 return 0; 2215 2216 if (off + count > hdev->rsize) 2217 count = hdev->rsize - off; 2218 2219 memcpy(buf, hdev->rdesc + off, count); 2220 2221 return count; 2222 } 2223 2224 static ssize_t 2225 country_show(struct device *dev, struct device_attribute *attr, 2226 char *buf) 2227 { 2228 struct hid_device *hdev = to_hid_device(dev); 2229 2230 return sprintf(buf, "%02x\n", hdev->country & 0xff); 2231 } 2232 2233 static const BIN_ATTR_RO(report_descriptor, HID_MAX_DESCRIPTOR_SIZE); 2234 2235 static const DEVICE_ATTR_RO(country); 2236 2237 int hid_connect(struct hid_device *hdev, unsigned int connect_mask) 2238 { 2239 static const char *types[] = { "Device", "Pointer", "Mouse", "Device", 2240 "Joystick", "Gamepad", "Keyboard", "Keypad", 2241 "Multi-Axis Controller" 2242 }; 2243 const char *type, *bus; 2244 char buf[64] = ""; 2245 unsigned int i; 2246 int len; 2247 int ret; 2248 2249 ret = hid_bpf_connect_device(hdev); 2250 if (ret) 2251 return ret; 2252 2253 if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE) 2254 connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV); 2255 if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE) 2256 connect_mask |= HID_CONNECT_HIDINPUT_FORCE; 2257 if (hdev->bus != BUS_USB) 2258 connect_mask &= ~HID_CONNECT_HIDDEV; 2259 if (hid_hiddev(hdev)) 2260 connect_mask |= HID_CONNECT_HIDDEV_FORCE; 2261 2262 if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev, 2263 connect_mask & HID_CONNECT_HIDINPUT_FORCE)) 2264 hdev->claimed |= HID_CLAIMED_INPUT; 2265 2266 if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect && 2267 !hdev->hiddev_connect(hdev, 2268 connect_mask & HID_CONNECT_HIDDEV_FORCE)) 2269 hdev->claimed |= HID_CLAIMED_HIDDEV; 2270 if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev)) 2271 hdev->claimed |= HID_CLAIMED_HIDRAW; 2272 2273 if (connect_mask & HID_CONNECT_DRIVER) 2274 hdev->claimed |= HID_CLAIMED_DRIVER; 2275 2276 /* Drivers with the ->raw_event callback set are not required to connect 2277 * to any other listener. */ 2278 if (!hdev->claimed && !hdev->driver->raw_event) { 2279 hid_err(hdev, "device has no listeners, quitting\n"); 2280 return -ENODEV; 2281 } 2282 2283 hid_process_ordering(hdev); 2284 2285 if ((hdev->claimed & HID_CLAIMED_INPUT) && 2286 (connect_mask & HID_CONNECT_FF) && hdev->ff_init) 2287 hdev->ff_init(hdev); 2288 2289 len = 0; 2290 if (hdev->claimed & HID_CLAIMED_INPUT) 2291 len += sprintf(buf + len, "input"); 2292 if (hdev->claimed & HID_CLAIMED_HIDDEV) 2293 len += sprintf(buf + len, "%shiddev%d", len ? "," : "", 2294 ((struct hiddev *)hdev->hiddev)->minor); 2295 if (hdev->claimed & HID_CLAIMED_HIDRAW) 2296 len += sprintf(buf + len, "%shidraw%d", len ? "," : "", 2297 ((struct hidraw *)hdev->hidraw)->minor); 2298 2299 type = "Device"; 2300 for (i = 0; i < hdev->maxcollection; i++) { 2301 struct hid_collection *col = &hdev->collection[i]; 2302 if (col->type == HID_COLLECTION_APPLICATION && 2303 (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK && 2304 (col->usage & 0xffff) < ARRAY_SIZE(types)) { 2305 type = types[col->usage & 0xffff]; 2306 break; 2307 } 2308 } 2309 2310 switch (hdev->bus) { 2311 case BUS_USB: 2312 bus = "USB"; 2313 break; 2314 case BUS_BLUETOOTH: 2315 bus = "BLUETOOTH"; 2316 break; 2317 case BUS_I2C: 2318 bus = "I2C"; 2319 break; 2320 case BUS_SDW: 2321 bus = "SOUNDWIRE"; 2322 break; 2323 case BUS_VIRTUAL: 2324 bus = "VIRTUAL"; 2325 break; 2326 case BUS_INTEL_ISHTP: 2327 case BUS_AMD_SFH: 2328 bus = "SENSOR HUB"; 2329 break; 2330 default: 2331 bus = "<UNKNOWN>"; 2332 } 2333 2334 ret = device_create_file(&hdev->dev, &dev_attr_country); 2335 if (ret) 2336 hid_warn(hdev, 2337 "can't create sysfs country code attribute err: %d\n", ret); 2338 2339 hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n", 2340 buf, bus, hdev->version >> 8, hdev->version & 0xff, 2341 type, hdev->name, hdev->phys); 2342 2343 return 0; 2344 } 2345 EXPORT_SYMBOL_GPL(hid_connect); 2346 2347 void hid_disconnect(struct hid_device *hdev) 2348 { 2349 device_remove_file(&hdev->dev, &dev_attr_country); 2350 if (hdev->claimed & HID_CLAIMED_INPUT) 2351 hidinput_disconnect(hdev); 2352 if (hdev->claimed & HID_CLAIMED_HIDDEV) 2353 hdev->hiddev_disconnect(hdev); 2354 if (hdev->claimed & HID_CLAIMED_HIDRAW) 2355 hidraw_disconnect(hdev); 2356 hdev->claimed = 0; 2357 2358 hid_bpf_disconnect_device(hdev); 2359 } 2360 EXPORT_SYMBOL_GPL(hid_disconnect); 2361 2362 /** 2363 * hid_hw_start - start underlying HW 2364 * @hdev: hid device 2365 * @connect_mask: which outputs to connect, see HID_CONNECT_* 2366 * 2367 * Call this in probe function *after* hid_parse. This will setup HW 2368 * buffers and start the device (if not defeirred to device open). 2369 * hid_hw_stop must be called if this was successful. 2370 */ 2371 int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask) 2372 { 2373 int error; 2374 2375 error = hdev->ll_driver->start(hdev); 2376 if (error) 2377 return error; 2378 2379 if (connect_mask) { 2380 error = hid_connect(hdev, connect_mask); 2381 if (error) { 2382 hdev->ll_driver->stop(hdev); 2383 return error; 2384 } 2385 } 2386 2387 return 0; 2388 } 2389 EXPORT_SYMBOL_GPL(hid_hw_start); 2390 2391 /** 2392 * hid_hw_stop - stop underlying HW 2393 * @hdev: hid device 2394 * 2395 * This is usually called from remove function or from probe when something 2396 * failed and hid_hw_start was called already. 2397 */ 2398 void hid_hw_stop(struct hid_device *hdev) 2399 { 2400 hid_disconnect(hdev); 2401 hdev->ll_driver->stop(hdev); 2402 } 2403 EXPORT_SYMBOL_GPL(hid_hw_stop); 2404 2405 /** 2406 * hid_hw_open - signal underlying HW to start delivering events 2407 * @hdev: hid device 2408 * 2409 * Tell underlying HW to start delivering events from the device. 2410 * This function should be called sometime after successful call 2411 * to hid_hw_start(). 2412 */ 2413 int hid_hw_open(struct hid_device *hdev) 2414 { 2415 int ret; 2416 2417 ret = mutex_lock_killable(&hdev->ll_open_lock); 2418 if (ret) 2419 return ret; 2420 2421 if (!hdev->ll_open_count++) { 2422 ret = hdev->ll_driver->open(hdev); 2423 if (ret) 2424 hdev->ll_open_count--; 2425 2426 if (hdev->driver->on_hid_hw_open) 2427 hdev->driver->on_hid_hw_open(hdev); 2428 } 2429 2430 mutex_unlock(&hdev->ll_open_lock); 2431 return ret; 2432 } 2433 EXPORT_SYMBOL_GPL(hid_hw_open); 2434 2435 /** 2436 * hid_hw_close - signal underlaying HW to stop delivering events 2437 * 2438 * @hdev: hid device 2439 * 2440 * This function indicates that we are not interested in the events 2441 * from this device anymore. Delivery of events may or may not stop, 2442 * depending on the number of users still outstanding. 2443 */ 2444 void hid_hw_close(struct hid_device *hdev) 2445 { 2446 mutex_lock(&hdev->ll_open_lock); 2447 if (!--hdev->ll_open_count) { 2448 hdev->ll_driver->close(hdev); 2449 2450 if (hdev->driver->on_hid_hw_close) 2451 hdev->driver->on_hid_hw_close(hdev); 2452 } 2453 mutex_unlock(&hdev->ll_open_lock); 2454 } 2455 EXPORT_SYMBOL_GPL(hid_hw_close); 2456 2457 /** 2458 * hid_hw_request - send report request to device 2459 * 2460 * @hdev: hid device 2461 * @report: report to send 2462 * @reqtype: hid request type 2463 */ 2464 void hid_hw_request(struct hid_device *hdev, 2465 struct hid_report *report, enum hid_class_request reqtype) 2466 { 2467 if (hdev->ll_driver->request) 2468 return hdev->ll_driver->request(hdev, report, reqtype); 2469 2470 __hid_request(hdev, report, reqtype); 2471 } 2472 EXPORT_SYMBOL_GPL(hid_hw_request); 2473 2474 int __hid_hw_raw_request(struct hid_device *hdev, 2475 unsigned char reportnum, __u8 *buf, 2476 size_t len, enum hid_report_type rtype, 2477 enum hid_class_request reqtype, 2478 u64 source, bool from_bpf) 2479 { 2480 unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE; 2481 int ret; 2482 2483 if (hdev->ll_driver->max_buffer_size) 2484 max_buffer_size = hdev->ll_driver->max_buffer_size; 2485 2486 if (len < 1 || len > max_buffer_size || !buf) 2487 return -EINVAL; 2488 2489 ret = dispatch_hid_bpf_raw_requests(hdev, reportnum, buf, len, rtype, 2490 reqtype, source, from_bpf); 2491 if (ret) 2492 return ret; 2493 2494 return hdev->ll_driver->raw_request(hdev, reportnum, buf, len, 2495 rtype, reqtype); 2496 } 2497 2498 /** 2499 * hid_hw_raw_request - send report request to device 2500 * 2501 * @hdev: hid device 2502 * @reportnum: report ID 2503 * @buf: in/out data to transfer 2504 * @len: length of buf 2505 * @rtype: HID report type 2506 * @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT 2507 * 2508 * Return: count of data transferred, negative if error 2509 * 2510 * Same behavior as hid_hw_request, but with raw buffers instead. 2511 */ 2512 int hid_hw_raw_request(struct hid_device *hdev, 2513 unsigned char reportnum, __u8 *buf, 2514 size_t len, enum hid_report_type rtype, enum hid_class_request reqtype) 2515 { 2516 return __hid_hw_raw_request(hdev, reportnum, buf, len, rtype, reqtype, 0, false); 2517 } 2518 EXPORT_SYMBOL_GPL(hid_hw_raw_request); 2519 2520 int __hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len, u64 source, 2521 bool from_bpf) 2522 { 2523 unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE; 2524 int ret; 2525 2526 if (hdev->ll_driver->max_buffer_size) 2527 max_buffer_size = hdev->ll_driver->max_buffer_size; 2528 2529 if (len < 1 || len > max_buffer_size || !buf) 2530 return -EINVAL; 2531 2532 ret = dispatch_hid_bpf_output_report(hdev, buf, len, source, from_bpf); 2533 if (ret) 2534 return ret; 2535 2536 if (hdev->ll_driver->output_report) 2537 return hdev->ll_driver->output_report(hdev, buf, len); 2538 2539 return -ENOSYS; 2540 } 2541 2542 /** 2543 * hid_hw_output_report - send output report to device 2544 * 2545 * @hdev: hid device 2546 * @buf: raw data to transfer 2547 * @len: length of buf 2548 * 2549 * Return: count of data transferred, negative if error 2550 */ 2551 int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len) 2552 { 2553 return __hid_hw_output_report(hdev, buf, len, 0, false); 2554 } 2555 EXPORT_SYMBOL_GPL(hid_hw_output_report); 2556 2557 #ifdef CONFIG_PM 2558 int hid_driver_suspend(struct hid_device *hdev, pm_message_t state) 2559 { 2560 if (hdev->driver && hdev->driver->suspend) 2561 return hdev->driver->suspend(hdev, state); 2562 2563 return 0; 2564 } 2565 EXPORT_SYMBOL_GPL(hid_driver_suspend); 2566 2567 int hid_driver_reset_resume(struct hid_device *hdev) 2568 { 2569 if (hdev->driver && hdev->driver->reset_resume) 2570 return hdev->driver->reset_resume(hdev); 2571 2572 return 0; 2573 } 2574 EXPORT_SYMBOL_GPL(hid_driver_reset_resume); 2575 2576 int hid_driver_resume(struct hid_device *hdev) 2577 { 2578 if (hdev->driver && hdev->driver->resume) 2579 return hdev->driver->resume(hdev); 2580 2581 return 0; 2582 } 2583 EXPORT_SYMBOL_GPL(hid_driver_resume); 2584 #endif /* CONFIG_PM */ 2585 2586 struct hid_dynid { 2587 struct list_head list; 2588 struct hid_device_id id; 2589 }; 2590 2591 /** 2592 * new_id_store - add a new HID device ID to this driver and re-probe devices 2593 * @drv: target device driver 2594 * @buf: buffer for scanning device ID data 2595 * @count: input size 2596 * 2597 * Adds a new dynamic hid device ID to this driver, 2598 * and causes the driver to probe for all devices again. 2599 */ 2600 static ssize_t new_id_store(struct device_driver *drv, const char *buf, 2601 size_t count) 2602 { 2603 struct hid_driver *hdrv = to_hid_driver(drv); 2604 struct hid_dynid *dynid; 2605 __u32 bus, vendor, product; 2606 unsigned long driver_data = 0; 2607 int ret; 2608 2609 ret = sscanf(buf, "%x %x %x %lx", 2610 &bus, &vendor, &product, &driver_data); 2611 if (ret < 3) 2612 return -EINVAL; 2613 2614 dynid = kzalloc_obj(*dynid, GFP_KERNEL); 2615 if (!dynid) 2616 return -ENOMEM; 2617 2618 dynid->id.bus = bus; 2619 dynid->id.group = HID_GROUP_ANY; 2620 dynid->id.vendor = vendor; 2621 dynid->id.product = product; 2622 dynid->id.driver_data = driver_data; 2623 2624 spin_lock(&hdrv->dyn_lock); 2625 list_add_tail(&dynid->list, &hdrv->dyn_list); 2626 spin_unlock(&hdrv->dyn_lock); 2627 2628 ret = driver_attach(&hdrv->driver); 2629 2630 return ret ? : count; 2631 } 2632 static DRIVER_ATTR_WO(new_id); 2633 2634 static struct attribute *hid_drv_attrs[] = { 2635 &driver_attr_new_id.attr, 2636 NULL, 2637 }; 2638 ATTRIBUTE_GROUPS(hid_drv); 2639 2640 static void hid_free_dynids(struct hid_driver *hdrv) 2641 { 2642 struct hid_dynid *dynid, *n; 2643 2644 spin_lock(&hdrv->dyn_lock); 2645 list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) { 2646 list_del(&dynid->list); 2647 kfree(dynid); 2648 } 2649 spin_unlock(&hdrv->dyn_lock); 2650 } 2651 2652 const struct hid_device_id *hid_match_device(struct hid_device *hdev, 2653 struct hid_driver *hdrv) 2654 { 2655 struct hid_dynid *dynid; 2656 2657 spin_lock(&hdrv->dyn_lock); 2658 list_for_each_entry(dynid, &hdrv->dyn_list, list) { 2659 if (hid_match_one_id(hdev, &dynid->id)) { 2660 spin_unlock(&hdrv->dyn_lock); 2661 return &dynid->id; 2662 } 2663 } 2664 spin_unlock(&hdrv->dyn_lock); 2665 2666 return hid_match_id(hdev, hdrv->id_table); 2667 } 2668 EXPORT_SYMBOL_GPL(hid_match_device); 2669 2670 static int hid_bus_match(struct device *dev, const struct device_driver *drv) 2671 { 2672 struct hid_driver *hdrv = to_hid_driver(drv); 2673 struct hid_device *hdev = to_hid_device(dev); 2674 2675 return hid_match_device(hdev, hdrv) != NULL; 2676 } 2677 2678 /** 2679 * hid_compare_device_paths - check if both devices share the same path 2680 * @hdev_a: hid device 2681 * @hdev_b: hid device 2682 * @separator: char to use as separator 2683 * 2684 * Check if two devices share the same path up to the last occurrence of 2685 * the separator char. Both paths must exist (i.e., zero-length paths 2686 * don't match). 2687 */ 2688 bool hid_compare_device_paths(struct hid_device *hdev_a, 2689 struct hid_device *hdev_b, char separator) 2690 { 2691 int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys; 2692 int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys; 2693 2694 if (n1 != n2 || n1 <= 0 || n2 <= 0) 2695 return false; 2696 2697 return !strncmp(hdev_a->phys, hdev_b->phys, n1); 2698 } 2699 EXPORT_SYMBOL_GPL(hid_compare_device_paths); 2700 2701 static bool hid_check_device_match(struct hid_device *hdev, 2702 struct hid_driver *hdrv, 2703 const struct hid_device_id **id) 2704 { 2705 *id = hid_match_device(hdev, hdrv); 2706 if (!*id) 2707 return false; 2708 2709 if (hdrv->match) 2710 return hdrv->match(hdev, hid_ignore_special_drivers); 2711 2712 /* 2713 * hid-generic implements .match(), so we must be dealing with a 2714 * different HID driver here, and can simply check if 2715 * hid_ignore_special_drivers or HID_QUIRK_IGNORE_SPECIAL_DRIVER 2716 * are set or not. 2717 */ 2718 return !hid_ignore_special_drivers && !(hdev->quirks & HID_QUIRK_IGNORE_SPECIAL_DRIVER); 2719 } 2720 2721 static void hid_set_group(struct hid_device *hdev) 2722 { 2723 int ret; 2724 2725 if (hid_ignore_special_drivers) { 2726 hdev->group = HID_GROUP_GENERIC; 2727 } else if (!hdev->group && 2728 !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) { 2729 ret = hid_scan_report(hdev); 2730 if (ret) 2731 hid_warn(hdev, "bad device descriptor (%d)\n", ret); 2732 } 2733 } 2734 2735 static int __hid_device_probe(struct hid_device *hdev, struct hid_driver *hdrv) 2736 { 2737 const struct hid_device_id *id; 2738 int ret; 2739 2740 if (!hdev->bpf_rsize) { 2741 /* we keep a reference to the currently scanned report descriptor */ 2742 const __u8 *original_rdesc = hdev->bpf_rdesc; 2743 2744 if (!original_rdesc) 2745 original_rdesc = hdev->dev_rdesc; 2746 2747 /* in case a bpf program gets detached, we need to free the old one */ 2748 hid_free_bpf_rdesc(hdev); 2749 2750 /* keep this around so we know we called it once */ 2751 hdev->bpf_rsize = hdev->dev_rsize; 2752 2753 /* call_hid_bpf_rdesc_fixup will always return a valid pointer */ 2754 hdev->bpf_rdesc = call_hid_bpf_rdesc_fixup(hdev, hdev->dev_rdesc, 2755 &hdev->bpf_rsize); 2756 2757 /* the report descriptor changed, we need to re-scan it */ 2758 if (original_rdesc != hdev->bpf_rdesc) { 2759 hdev->group = 0; 2760 hid_set_group(hdev); 2761 } 2762 } 2763 2764 if (!hid_check_device_match(hdev, hdrv, &id)) 2765 return -ENODEV; 2766 2767 hdev->devres_group_id = devres_open_group(&hdev->dev, NULL, GFP_KERNEL); 2768 if (!hdev->devres_group_id) 2769 return -ENOMEM; 2770 2771 /* reset the quirks that has been previously set */ 2772 hdev->quirks = hid_lookup_quirk(hdev); 2773 hdev->driver = hdrv; 2774 2775 if (hdrv->probe) { 2776 ret = hdrv->probe(hdev, id); 2777 } else { /* default probe */ 2778 ret = hid_open_report(hdev); 2779 if (!ret) 2780 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); 2781 } 2782 2783 /* 2784 * Note that we are not closing the devres group opened above so 2785 * even resources that were attached to the device after probe is 2786 * run are released when hid_device_remove() is executed. This is 2787 * needed as some drivers would allocate additional resources, 2788 * for example when updating firmware. 2789 */ 2790 2791 if (ret) { 2792 devres_release_group(&hdev->dev, hdev->devres_group_id); 2793 hid_close_report(hdev); 2794 hdev->driver = NULL; 2795 } 2796 2797 return ret; 2798 } 2799 2800 static int hid_device_probe(struct device *dev) 2801 { 2802 struct hid_device *hdev = to_hid_device(dev); 2803 struct hid_driver *hdrv = to_hid_driver(dev->driver); 2804 int ret = 0; 2805 2806 if (down_interruptible(&hdev->driver_input_lock)) 2807 return -EINTR; 2808 2809 hdev->io_started = false; 2810 clear_bit(ffs(HID_STAT_REPROBED), &hdev->status); 2811 2812 if (!hdev->driver) 2813 ret = __hid_device_probe(hdev, hdrv); 2814 2815 if (!hdev->io_started) 2816 up(&hdev->driver_input_lock); 2817 2818 return ret; 2819 } 2820 2821 static void hid_device_remove(struct device *dev) 2822 { 2823 struct hid_device *hdev = to_hid_device(dev); 2824 struct hid_driver *hdrv; 2825 2826 down(&hdev->driver_input_lock); 2827 hdev->io_started = false; 2828 2829 hdrv = hdev->driver; 2830 if (hdrv) { 2831 if (hdrv->remove) 2832 hdrv->remove(hdev); 2833 else /* default remove */ 2834 hid_hw_stop(hdev); 2835 2836 /* Release all devres resources allocated by the driver */ 2837 devres_release_group(&hdev->dev, hdev->devres_group_id); 2838 2839 hid_close_report(hdev); 2840 hdev->driver = NULL; 2841 } 2842 2843 if (!hdev->io_started) 2844 up(&hdev->driver_input_lock); 2845 } 2846 2847 static ssize_t modalias_show(struct device *dev, struct device_attribute *a, 2848 char *buf) 2849 { 2850 struct hid_device *hdev = container_of(dev, struct hid_device, dev); 2851 2852 return sysfs_emit(buf, "hid:b%04Xg%04Xv%08Xp%08X\n", 2853 hdev->bus, hdev->group, hdev->vendor, hdev->product); 2854 } 2855 static DEVICE_ATTR_RO(modalias); 2856 2857 static struct attribute *hid_dev_attrs[] = { 2858 &dev_attr_modalias.attr, 2859 NULL, 2860 }; 2861 static const struct bin_attribute *hid_dev_bin_attrs[] = { 2862 &bin_attr_report_descriptor, 2863 NULL 2864 }; 2865 static const struct attribute_group hid_dev_group = { 2866 .attrs = hid_dev_attrs, 2867 .bin_attrs = hid_dev_bin_attrs, 2868 }; 2869 __ATTRIBUTE_GROUPS(hid_dev); 2870 2871 static int hid_uevent(const struct device *dev, struct kobj_uevent_env *env) 2872 { 2873 const struct hid_device *hdev = to_hid_device(dev); 2874 2875 if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X", 2876 hdev->bus, hdev->vendor, hdev->product)) 2877 return -ENOMEM; 2878 2879 if (add_uevent_var(env, "HID_NAME=%s", hdev->name)) 2880 return -ENOMEM; 2881 2882 if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys)) 2883 return -ENOMEM; 2884 2885 if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq)) 2886 return -ENOMEM; 2887 2888 if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X", 2889 hdev->bus, hdev->group, hdev->vendor, hdev->product)) 2890 return -ENOMEM; 2891 2892 return 0; 2893 } 2894 2895 const struct bus_type hid_bus_type = { 2896 .name = "hid", 2897 .dev_groups = hid_dev_groups, 2898 .drv_groups = hid_drv_groups, 2899 .match = hid_bus_match, 2900 .probe = hid_device_probe, 2901 .remove = hid_device_remove, 2902 .uevent = hid_uevent, 2903 }; 2904 EXPORT_SYMBOL(hid_bus_type); 2905 2906 int hid_add_device(struct hid_device *hdev) 2907 { 2908 static atomic_t id = ATOMIC_INIT(0); 2909 int ret; 2910 2911 if (WARN_ON(hdev->status & HID_STAT_ADDED)) 2912 return -EBUSY; 2913 2914 hdev->quirks = hid_lookup_quirk(hdev); 2915 2916 /* we need to kill them here, otherwise they will stay allocated to 2917 * wait for coming driver */ 2918 if (hid_ignore(hdev)) 2919 return -ENODEV; 2920 2921 /* 2922 * Check for the mandatory transport channel. 2923 */ 2924 if (!hdev->ll_driver->raw_request) { 2925 hid_err(hdev, "transport driver missing .raw_request()\n"); 2926 return -EINVAL; 2927 } 2928 2929 /* 2930 * Read the device report descriptor once and use as template 2931 * for the driver-specific modifications. 2932 */ 2933 ret = hdev->ll_driver->parse(hdev); 2934 if (ret) 2935 return ret; 2936 if (!hdev->dev_rdesc) 2937 return -ENODEV; 2938 2939 /* 2940 * Scan generic devices for group information 2941 */ 2942 hid_set_group(hdev); 2943 2944 hdev->id = atomic_inc_return(&id); 2945 2946 /* XXX hack, any other cleaner solution after the driver core 2947 * is converted to allow more than 20 bytes as the device name? */ 2948 dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus, 2949 hdev->vendor, hdev->product, hdev->id); 2950 2951 hid_debug_register(hdev, dev_name(&hdev->dev)); 2952 ret = device_add(&hdev->dev); 2953 if (!ret) 2954 hdev->status |= HID_STAT_ADDED; 2955 else 2956 hid_debug_unregister(hdev); 2957 2958 return ret; 2959 } 2960 EXPORT_SYMBOL_GPL(hid_add_device); 2961 2962 /** 2963 * hid_allocate_device - allocate new hid device descriptor 2964 * 2965 * Allocate and initialize hid device, so that hid_destroy_device might be 2966 * used to free it. 2967 * 2968 * New hid_device pointer is returned on success, otherwise ERR_PTR encoded 2969 * error value. 2970 */ 2971 struct hid_device *hid_allocate_device(void) 2972 { 2973 struct hid_device *hdev; 2974 int ret = -ENOMEM; 2975 2976 hdev = kzalloc_obj(*hdev, GFP_KERNEL); 2977 if (hdev == NULL) 2978 return ERR_PTR(ret); 2979 2980 device_initialize(&hdev->dev); 2981 hdev->dev.release = hid_device_release; 2982 hdev->dev.bus = &hid_bus_type; 2983 device_enable_async_suspend(&hdev->dev); 2984 2985 hid_close_report(hdev); 2986 2987 init_waitqueue_head(&hdev->debug_wait); 2988 INIT_LIST_HEAD(&hdev->debug_list); 2989 spin_lock_init(&hdev->debug_list_lock); 2990 sema_init(&hdev->driver_input_lock, 1); 2991 mutex_init(&hdev->ll_open_lock); 2992 kref_init(&hdev->ref); 2993 2994 ret = hid_bpf_device_init(hdev); 2995 if (ret) 2996 goto out_err; 2997 2998 return hdev; 2999 3000 out_err: 3001 hid_destroy_device(hdev); 3002 return ERR_PTR(ret); 3003 } 3004 EXPORT_SYMBOL_GPL(hid_allocate_device); 3005 3006 static void hid_remove_device(struct hid_device *hdev) 3007 { 3008 if (hdev->status & HID_STAT_ADDED) { 3009 device_del(&hdev->dev); 3010 hid_debug_unregister(hdev); 3011 hdev->status &= ~HID_STAT_ADDED; 3012 } 3013 hid_free_bpf_rdesc(hdev); 3014 kfree(hdev->dev_rdesc); 3015 hdev->dev_rdesc = NULL; 3016 hdev->dev_rsize = 0; 3017 hdev->bpf_rsize = 0; 3018 } 3019 3020 /** 3021 * hid_destroy_device - free previously allocated device 3022 * 3023 * @hdev: hid device 3024 * 3025 * If you allocate hid_device through hid_allocate_device, you should ever 3026 * free by this function. 3027 */ 3028 void hid_destroy_device(struct hid_device *hdev) 3029 { 3030 hid_bpf_destroy_device(hdev); 3031 hid_remove_device(hdev); 3032 put_device(&hdev->dev); 3033 } 3034 EXPORT_SYMBOL_GPL(hid_destroy_device); 3035 3036 3037 static int __hid_bus_reprobe_drivers(struct device *dev, void *data) 3038 { 3039 struct hid_driver *hdrv = data; 3040 struct hid_device *hdev = to_hid_device(dev); 3041 3042 if (hdev->driver == hdrv && 3043 !hdrv->match(hdev, hid_ignore_special_drivers) && 3044 !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status)) 3045 return device_reprobe(dev); 3046 3047 return 0; 3048 } 3049 3050 static int __hid_bus_driver_added(struct device_driver *drv, void *data) 3051 { 3052 struct hid_driver *hdrv = to_hid_driver(drv); 3053 3054 if (hdrv->match) { 3055 bus_for_each_dev(&hid_bus_type, NULL, hdrv, 3056 __hid_bus_reprobe_drivers); 3057 } 3058 3059 return 0; 3060 } 3061 3062 static int __bus_removed_driver(struct device_driver *drv, void *data) 3063 { 3064 return bus_rescan_devices(&hid_bus_type); 3065 } 3066 3067 int __hid_register_driver(struct hid_driver *hdrv, struct module *owner, 3068 const char *mod_name) 3069 { 3070 int ret; 3071 3072 hdrv->driver.name = hdrv->name; 3073 hdrv->driver.bus = &hid_bus_type; 3074 hdrv->driver.owner = owner; 3075 hdrv->driver.mod_name = mod_name; 3076 3077 INIT_LIST_HEAD(&hdrv->dyn_list); 3078 spin_lock_init(&hdrv->dyn_lock); 3079 3080 ret = driver_register(&hdrv->driver); 3081 3082 if (ret == 0) 3083 bus_for_each_drv(&hid_bus_type, NULL, NULL, 3084 __hid_bus_driver_added); 3085 3086 return ret; 3087 } 3088 EXPORT_SYMBOL_GPL(__hid_register_driver); 3089 3090 void hid_unregister_driver(struct hid_driver *hdrv) 3091 { 3092 driver_unregister(&hdrv->driver); 3093 hid_free_dynids(hdrv); 3094 3095 bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver); 3096 } 3097 EXPORT_SYMBOL_GPL(hid_unregister_driver); 3098 3099 int hid_check_keys_pressed(struct hid_device *hid) 3100 { 3101 struct hid_input *hidinput; 3102 int i; 3103 3104 if (!(hid->claimed & HID_CLAIMED_INPUT)) 3105 return 0; 3106 3107 list_for_each_entry(hidinput, &hid->inputs, list) { 3108 for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++) 3109 if (hidinput->input->key[i]) 3110 return 1; 3111 } 3112 3113 return 0; 3114 } 3115 EXPORT_SYMBOL_GPL(hid_check_keys_pressed); 3116 3117 #ifdef CONFIG_HID_BPF 3118 static const struct hid_ops __hid_ops = { 3119 .hid_get_report = hid_get_report, 3120 .hid_hw_raw_request = __hid_hw_raw_request, 3121 .hid_hw_output_report = __hid_hw_output_report, 3122 .hid_input_report = __hid_input_report, 3123 .owner = THIS_MODULE, 3124 .bus_type = &hid_bus_type, 3125 }; 3126 #endif 3127 3128 static int __init hid_init(void) 3129 { 3130 int ret; 3131 3132 ret = bus_register(&hid_bus_type); 3133 if (ret) { 3134 pr_err("can't register hid bus\n"); 3135 goto err; 3136 } 3137 3138 #ifdef CONFIG_HID_BPF 3139 hid_ops = &__hid_ops; 3140 #endif 3141 3142 ret = hidraw_init(); 3143 if (ret) 3144 goto err_bus; 3145 3146 hid_debug_init(); 3147 3148 return 0; 3149 err_bus: 3150 bus_unregister(&hid_bus_type); 3151 err: 3152 return ret; 3153 } 3154 3155 static void __exit hid_exit(void) 3156 { 3157 #ifdef CONFIG_HID_BPF 3158 hid_ops = NULL; 3159 #endif 3160 hid_debug_exit(); 3161 hidraw_exit(); 3162 bus_unregister(&hid_bus_type); 3163 hid_quirks_exit(HID_BUS_ANY); 3164 } 3165 3166 module_init(hid_init); 3167 module_exit(hid_exit); 3168 3169 MODULE_AUTHOR("Andreas Gal"); 3170 MODULE_AUTHOR("Vojtech Pavlik"); 3171 MODULE_AUTHOR("Jiri Kosina"); 3172 MODULE_DESCRIPTION("HID support for Linux"); 3173 MODULE_LICENSE("GPL"); 3174