Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 1 | /* |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 2 | * HID support for Linux |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 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> |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 21 | #include <linux/list.h> |
| 22 | #include <linux/mm.h> |
| 23 | #include <linux/smp_lock.h> |
| 24 | #include <linux/spinlock.h> |
| 25 | #include <asm/unaligned.h> |
| 26 | #include <asm/byteorder.h> |
| 27 | #include <linux/input.h> |
| 28 | #include <linux/wait.h> |
| 29 | |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 30 | #include <linux/hid.h> |
| 31 | #include <linux/hiddev.h> |
Jiri Kosina | c080d89 | 2007-01-25 11:43:31 +0100 | [diff] [blame] | 32 | #include <linux/hid-debug.h> |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 33 | |
| 34 | /* |
| 35 | * Version Information |
| 36 | */ |
| 37 | |
| 38 | #define DRIVER_VERSION "v2.6" |
| 39 | #define DRIVER_AUTHOR "Andreas Gal, Vojtech Pavlik" |
Jiri Kosina | 5314980 | 2007-01-09 13:24:25 +0100 | [diff] [blame] | 40 | #define DRIVER_DESC "HID core driver" |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 41 | #define DRIVER_LICENSE "GPL" |
| 42 | |
| 43 | /* |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 44 | * Register a new report for a device. |
| 45 | */ |
| 46 | |
| 47 | static struct hid_report *hid_register_report(struct hid_device *device, unsigned type, unsigned id) |
| 48 | { |
| 49 | struct hid_report_enum *report_enum = device->report_enum + type; |
| 50 | struct hid_report *report; |
| 51 | |
| 52 | if (report_enum->report_id_hash[id]) |
| 53 | return report_enum->report_id_hash[id]; |
| 54 | |
| 55 | if (!(report = kzalloc(sizeof(struct hid_report), GFP_KERNEL))) |
| 56 | return NULL; |
| 57 | |
| 58 | if (id != 0) |
| 59 | report_enum->numbered = 1; |
| 60 | |
| 61 | report->id = id; |
| 62 | report->type = type; |
| 63 | report->size = 0; |
| 64 | report->device = device; |
| 65 | report_enum->report_id_hash[id] = report; |
| 66 | |
| 67 | list_add_tail(&report->list, &report_enum->report_list); |
| 68 | |
| 69 | return report; |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Register a new field for this report. |
| 74 | */ |
| 75 | |
| 76 | static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values) |
| 77 | { |
| 78 | struct hid_field *field; |
| 79 | |
| 80 | if (report->maxfield == HID_MAX_FIELDS) { |
| 81 | dbg("too many fields in report"); |
| 82 | return NULL; |
| 83 | } |
| 84 | |
| 85 | if (!(field = kzalloc(sizeof(struct hid_field) + usages * sizeof(struct hid_usage) |
| 86 | + values * sizeof(unsigned), GFP_KERNEL))) return NULL; |
| 87 | |
| 88 | field->index = report->maxfield++; |
| 89 | report->field[field->index] = field; |
| 90 | field->usage = (struct hid_usage *)(field + 1); |
| 91 | field->value = (unsigned *)(field->usage + usages); |
| 92 | field->report = report; |
| 93 | |
| 94 | return field; |
| 95 | } |
| 96 | |
| 97 | /* |
| 98 | * Open a collection. The type/usage is pushed on the stack. |
| 99 | */ |
| 100 | |
| 101 | static int open_collection(struct hid_parser *parser, unsigned type) |
| 102 | { |
| 103 | struct hid_collection *collection; |
| 104 | unsigned usage; |
| 105 | |
| 106 | usage = parser->local.usage[0]; |
| 107 | |
| 108 | if (parser->collection_stack_ptr == HID_COLLECTION_STACK_SIZE) { |
| 109 | dbg("collection stack overflow"); |
| 110 | return -1; |
| 111 | } |
| 112 | |
| 113 | if (parser->device->maxcollection == parser->device->collection_size) { |
| 114 | collection = kmalloc(sizeof(struct hid_collection) * |
| 115 | parser->device->collection_size * 2, GFP_KERNEL); |
| 116 | if (collection == NULL) { |
| 117 | dbg("failed to reallocate collection array"); |
| 118 | return -1; |
| 119 | } |
| 120 | memcpy(collection, parser->device->collection, |
| 121 | sizeof(struct hid_collection) * |
| 122 | parser->device->collection_size); |
| 123 | memset(collection + parser->device->collection_size, 0, |
| 124 | sizeof(struct hid_collection) * |
| 125 | parser->device->collection_size); |
| 126 | kfree(parser->device->collection); |
| 127 | parser->device->collection = collection; |
| 128 | parser->device->collection_size *= 2; |
| 129 | } |
| 130 | |
| 131 | parser->collection_stack[parser->collection_stack_ptr++] = |
| 132 | parser->device->maxcollection; |
| 133 | |
| 134 | collection = parser->device->collection + |
| 135 | parser->device->maxcollection++; |
| 136 | collection->type = type; |
| 137 | collection->usage = usage; |
| 138 | collection->level = parser->collection_stack_ptr - 1; |
| 139 | |
| 140 | if (type == HID_COLLECTION_APPLICATION) |
| 141 | parser->device->maxapplication++; |
| 142 | |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | /* |
| 147 | * Close a collection. |
| 148 | */ |
| 149 | |
| 150 | static int close_collection(struct hid_parser *parser) |
| 151 | { |
| 152 | if (!parser->collection_stack_ptr) { |
| 153 | dbg("collection stack underflow"); |
| 154 | return -1; |
| 155 | } |
| 156 | parser->collection_stack_ptr--; |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | /* |
| 161 | * Climb up the stack, search for the specified collection type |
| 162 | * and return the usage. |
| 163 | */ |
| 164 | |
| 165 | static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) |
| 166 | { |
| 167 | int n; |
| 168 | for (n = parser->collection_stack_ptr - 1; n >= 0; n--) |
| 169 | if (parser->device->collection[parser->collection_stack[n]].type == type) |
| 170 | return parser->device->collection[parser->collection_stack[n]].usage; |
| 171 | return 0; /* we know nothing about this usage type */ |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * Add a usage to the temporary parser table. |
| 176 | */ |
| 177 | |
| 178 | static int hid_add_usage(struct hid_parser *parser, unsigned usage) |
| 179 | { |
| 180 | if (parser->local.usage_index >= HID_MAX_USAGES) { |
| 181 | dbg("usage index exceeded"); |
| 182 | return -1; |
| 183 | } |
| 184 | parser->local.usage[parser->local.usage_index] = usage; |
| 185 | parser->local.collection_index[parser->local.usage_index] = |
| 186 | parser->collection_stack_ptr ? |
| 187 | parser->collection_stack[parser->collection_stack_ptr - 1] : 0; |
| 188 | parser->local.usage_index++; |
| 189 | return 0; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * Register a new field for this report. |
| 194 | */ |
| 195 | |
| 196 | static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags) |
| 197 | { |
| 198 | struct hid_report *report; |
| 199 | struct hid_field *field; |
| 200 | int usages; |
| 201 | unsigned offset; |
| 202 | int i; |
| 203 | |
| 204 | if (!(report = hid_register_report(parser->device, report_type, parser->global.report_id))) { |
| 205 | dbg("hid_register_report failed"); |
| 206 | return -1; |
| 207 | } |
| 208 | |
| 209 | if (parser->global.logical_maximum < parser->global.logical_minimum) { |
| 210 | dbg("logical range invalid %d %d", parser->global.logical_minimum, parser->global.logical_maximum); |
| 211 | return -1; |
| 212 | } |
| 213 | |
| 214 | offset = report->size; |
| 215 | report->size += parser->global.report_size * parser->global.report_count; |
| 216 | |
| 217 | if (!parser->local.usage_index) /* Ignore padding fields */ |
| 218 | return 0; |
| 219 | |
| 220 | usages = max_t(int, parser->local.usage_index, parser->global.report_count); |
| 221 | |
| 222 | if ((field = hid_register_field(report, usages, parser->global.report_count)) == NULL) |
| 223 | return 0; |
| 224 | |
| 225 | field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL); |
| 226 | field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL); |
| 227 | field->application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); |
| 228 | |
| 229 | for (i = 0; i < usages; i++) { |
| 230 | int j = i; |
| 231 | /* Duplicate the last usage we parsed if we have excess values */ |
| 232 | if (i >= parser->local.usage_index) |
| 233 | j = parser->local.usage_index - 1; |
| 234 | field->usage[i].hid = parser->local.usage[j]; |
| 235 | field->usage[i].collection_index = |
| 236 | parser->local.collection_index[j]; |
| 237 | } |
| 238 | |
| 239 | field->maxusage = usages; |
| 240 | field->flags = flags; |
| 241 | field->report_offset = offset; |
| 242 | field->report_type = report_type; |
| 243 | field->report_size = parser->global.report_size; |
| 244 | field->report_count = parser->global.report_count; |
| 245 | field->logical_minimum = parser->global.logical_minimum; |
| 246 | field->logical_maximum = parser->global.logical_maximum; |
| 247 | field->physical_minimum = parser->global.physical_minimum; |
| 248 | field->physical_maximum = parser->global.physical_maximum; |
| 249 | field->unit_exponent = parser->global.unit_exponent; |
| 250 | field->unit = parser->global.unit; |
| 251 | |
| 252 | return 0; |
| 253 | } |
| 254 | |
| 255 | /* |
| 256 | * Read data value from item. |
| 257 | */ |
| 258 | |
| 259 | static u32 item_udata(struct hid_item *item) |
| 260 | { |
| 261 | switch (item->size) { |
| 262 | case 1: return item->data.u8; |
| 263 | case 2: return item->data.u16; |
| 264 | case 4: return item->data.u32; |
| 265 | } |
| 266 | return 0; |
| 267 | } |
| 268 | |
| 269 | static s32 item_sdata(struct hid_item *item) |
| 270 | { |
| 271 | switch (item->size) { |
| 272 | case 1: return item->data.s8; |
| 273 | case 2: return item->data.s16; |
| 274 | case 4: return item->data.s32; |
| 275 | } |
| 276 | return 0; |
| 277 | } |
| 278 | |
| 279 | /* |
| 280 | * Process a global item. |
| 281 | */ |
| 282 | |
| 283 | static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) |
| 284 | { |
| 285 | switch (item->tag) { |
| 286 | |
| 287 | case HID_GLOBAL_ITEM_TAG_PUSH: |
| 288 | |
| 289 | if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) { |
| 290 | dbg("global enviroment stack overflow"); |
| 291 | return -1; |
| 292 | } |
| 293 | |
| 294 | memcpy(parser->global_stack + parser->global_stack_ptr++, |
| 295 | &parser->global, sizeof(struct hid_global)); |
| 296 | return 0; |
| 297 | |
| 298 | case HID_GLOBAL_ITEM_TAG_POP: |
| 299 | |
| 300 | if (!parser->global_stack_ptr) { |
| 301 | dbg("global enviroment stack underflow"); |
| 302 | return -1; |
| 303 | } |
| 304 | |
| 305 | memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr, |
| 306 | sizeof(struct hid_global)); |
| 307 | return 0; |
| 308 | |
| 309 | case HID_GLOBAL_ITEM_TAG_USAGE_PAGE: |
| 310 | parser->global.usage_page = item_udata(item); |
| 311 | return 0; |
| 312 | |
| 313 | case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM: |
| 314 | parser->global.logical_minimum = item_sdata(item); |
| 315 | return 0; |
| 316 | |
| 317 | case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM: |
| 318 | if (parser->global.logical_minimum < 0) |
| 319 | parser->global.logical_maximum = item_sdata(item); |
| 320 | else |
| 321 | parser->global.logical_maximum = item_udata(item); |
| 322 | return 0; |
| 323 | |
| 324 | case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM: |
| 325 | parser->global.physical_minimum = item_sdata(item); |
| 326 | return 0; |
| 327 | |
| 328 | case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM: |
| 329 | if (parser->global.physical_minimum < 0) |
| 330 | parser->global.physical_maximum = item_sdata(item); |
| 331 | else |
| 332 | parser->global.physical_maximum = item_udata(item); |
| 333 | return 0; |
| 334 | |
| 335 | case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: |
| 336 | parser->global.unit_exponent = item_sdata(item); |
| 337 | return 0; |
| 338 | |
| 339 | case HID_GLOBAL_ITEM_TAG_UNIT: |
| 340 | parser->global.unit = item_udata(item); |
| 341 | return 0; |
| 342 | |
| 343 | case HID_GLOBAL_ITEM_TAG_REPORT_SIZE: |
| 344 | if ((parser->global.report_size = item_udata(item)) > 32) { |
| 345 | dbg("invalid report_size %d", parser->global.report_size); |
| 346 | return -1; |
| 347 | } |
| 348 | return 0; |
| 349 | |
| 350 | case HID_GLOBAL_ITEM_TAG_REPORT_COUNT: |
| 351 | if ((parser->global.report_count = item_udata(item)) > HID_MAX_USAGES) { |
| 352 | dbg("invalid report_count %d", parser->global.report_count); |
| 353 | return -1; |
| 354 | } |
| 355 | return 0; |
| 356 | |
| 357 | case HID_GLOBAL_ITEM_TAG_REPORT_ID: |
| 358 | if ((parser->global.report_id = item_udata(item)) == 0) { |
| 359 | dbg("report_id 0 is invalid"); |
| 360 | return -1; |
| 361 | } |
| 362 | return 0; |
| 363 | |
| 364 | default: |
| 365 | dbg("unknown global tag 0x%x", item->tag); |
| 366 | return -1; |
| 367 | } |
| 368 | } |
| 369 | |
| 370 | /* |
| 371 | * Process a local item. |
| 372 | */ |
| 373 | |
| 374 | static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) |
| 375 | { |
| 376 | __u32 data; |
| 377 | unsigned n; |
| 378 | |
| 379 | if (item->size == 0) { |
| 380 | dbg("item data expected for local item"); |
| 381 | return -1; |
| 382 | } |
| 383 | |
| 384 | data = item_udata(item); |
| 385 | |
| 386 | switch (item->tag) { |
| 387 | |
| 388 | case HID_LOCAL_ITEM_TAG_DELIMITER: |
| 389 | |
| 390 | if (data) { |
| 391 | /* |
| 392 | * We treat items before the first delimiter |
| 393 | * as global to all usage sets (branch 0). |
| 394 | * In the moment we process only these global |
| 395 | * items and the first delimiter set. |
| 396 | */ |
| 397 | if (parser->local.delimiter_depth != 0) { |
| 398 | dbg("nested delimiters"); |
| 399 | return -1; |
| 400 | } |
| 401 | parser->local.delimiter_depth++; |
| 402 | parser->local.delimiter_branch++; |
| 403 | } else { |
| 404 | if (parser->local.delimiter_depth < 1) { |
| 405 | dbg("bogus close delimiter"); |
| 406 | return -1; |
| 407 | } |
| 408 | parser->local.delimiter_depth--; |
| 409 | } |
| 410 | return 1; |
| 411 | |
| 412 | case HID_LOCAL_ITEM_TAG_USAGE: |
| 413 | |
| 414 | if (parser->local.delimiter_branch > 1) { |
| 415 | dbg("alternative usage ignored"); |
| 416 | return 0; |
| 417 | } |
| 418 | |
| 419 | if (item->size <= 2) |
| 420 | data = (parser->global.usage_page << 16) + data; |
| 421 | |
| 422 | return hid_add_usage(parser, data); |
| 423 | |
| 424 | case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: |
| 425 | |
| 426 | if (parser->local.delimiter_branch > 1) { |
| 427 | dbg("alternative usage ignored"); |
| 428 | return 0; |
| 429 | } |
| 430 | |
| 431 | if (item->size <= 2) |
| 432 | data = (parser->global.usage_page << 16) + data; |
| 433 | |
| 434 | parser->local.usage_minimum = data; |
| 435 | return 0; |
| 436 | |
| 437 | case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: |
| 438 | |
| 439 | if (parser->local.delimiter_branch > 1) { |
| 440 | dbg("alternative usage ignored"); |
| 441 | return 0; |
| 442 | } |
| 443 | |
| 444 | if (item->size <= 2) |
| 445 | data = (parser->global.usage_page << 16) + data; |
| 446 | |
| 447 | for (n = parser->local.usage_minimum; n <= data; n++) |
| 448 | if (hid_add_usage(parser, n)) { |
| 449 | dbg("hid_add_usage failed\n"); |
| 450 | return -1; |
| 451 | } |
| 452 | return 0; |
| 453 | |
| 454 | default: |
| 455 | |
| 456 | dbg("unknown local item tag 0x%x", item->tag); |
| 457 | return 0; |
| 458 | } |
| 459 | return 0; |
| 460 | } |
| 461 | |
| 462 | /* |
| 463 | * Process a main item. |
| 464 | */ |
| 465 | |
| 466 | static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) |
| 467 | { |
| 468 | __u32 data; |
| 469 | int ret; |
| 470 | |
| 471 | data = item_udata(item); |
| 472 | |
| 473 | switch (item->tag) { |
| 474 | case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: |
| 475 | ret = open_collection(parser, data & 0xff); |
| 476 | break; |
| 477 | case HID_MAIN_ITEM_TAG_END_COLLECTION: |
| 478 | ret = close_collection(parser); |
| 479 | break; |
| 480 | case HID_MAIN_ITEM_TAG_INPUT: |
| 481 | ret = hid_add_field(parser, HID_INPUT_REPORT, data); |
| 482 | break; |
| 483 | case HID_MAIN_ITEM_TAG_OUTPUT: |
| 484 | ret = hid_add_field(parser, HID_OUTPUT_REPORT, data); |
| 485 | break; |
| 486 | case HID_MAIN_ITEM_TAG_FEATURE: |
| 487 | ret = hid_add_field(parser, HID_FEATURE_REPORT, data); |
| 488 | break; |
| 489 | default: |
| 490 | dbg("unknown main item tag 0x%x", item->tag); |
| 491 | ret = 0; |
| 492 | } |
| 493 | |
| 494 | memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */ |
| 495 | |
| 496 | return ret; |
| 497 | } |
| 498 | |
| 499 | /* |
| 500 | * Process a reserved item. |
| 501 | */ |
| 502 | |
| 503 | static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item) |
| 504 | { |
| 505 | dbg("reserved item type, tag 0x%x", item->tag); |
| 506 | return 0; |
| 507 | } |
| 508 | |
| 509 | /* |
| 510 | * Free a report and all registered fields. The field->usage and |
| 511 | * field->value table's are allocated behind the field, so we need |
| 512 | * only to free(field) itself. |
| 513 | */ |
| 514 | |
| 515 | static void hid_free_report(struct hid_report *report) |
| 516 | { |
| 517 | unsigned n; |
| 518 | |
| 519 | for (n = 0; n < report->maxfield; n++) |
| 520 | kfree(report->field[n]); |
| 521 | kfree(report); |
| 522 | } |
| 523 | |
| 524 | /* |
| 525 | * Free a device structure, all reports, and all fields. |
| 526 | */ |
| 527 | |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 528 | void hid_free_device(struct hid_device *device) |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 529 | { |
| 530 | unsigned i,j; |
| 531 | |
| 532 | for (i = 0; i < HID_REPORT_TYPES; i++) { |
| 533 | struct hid_report_enum *report_enum = device->report_enum + i; |
| 534 | |
| 535 | for (j = 0; j < 256; j++) { |
| 536 | struct hid_report *report = report_enum->report_id_hash[j]; |
| 537 | if (report) |
| 538 | hid_free_report(report); |
| 539 | } |
| 540 | } |
| 541 | |
| 542 | kfree(device->rdesc); |
Jiri Kosina | 767fe78 | 2007-01-24 23:05:07 +0100 | [diff] [blame] | 543 | kfree(device->collection); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 544 | kfree(device); |
| 545 | } |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 546 | EXPORT_SYMBOL_GPL(hid_free_device); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 547 | |
| 548 | /* |
| 549 | * Fetch a report description item from the data stream. We support long |
| 550 | * items, though they are not used yet. |
| 551 | */ |
| 552 | |
| 553 | static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item) |
| 554 | { |
| 555 | u8 b; |
| 556 | |
| 557 | if ((end - start) <= 0) |
| 558 | return NULL; |
| 559 | |
| 560 | b = *start++; |
| 561 | |
| 562 | item->type = (b >> 2) & 3; |
| 563 | item->tag = (b >> 4) & 15; |
| 564 | |
| 565 | if (item->tag == HID_ITEM_TAG_LONG) { |
| 566 | |
| 567 | item->format = HID_ITEM_FORMAT_LONG; |
| 568 | |
| 569 | if ((end - start) < 2) |
| 570 | return NULL; |
| 571 | |
| 572 | item->size = *start++; |
| 573 | item->tag = *start++; |
| 574 | |
| 575 | if ((end - start) < item->size) |
| 576 | return NULL; |
| 577 | |
| 578 | item->data.longdata = start; |
| 579 | start += item->size; |
| 580 | return start; |
| 581 | } |
| 582 | |
| 583 | item->format = HID_ITEM_FORMAT_SHORT; |
| 584 | item->size = b & 3; |
| 585 | |
| 586 | switch (item->size) { |
| 587 | |
| 588 | case 0: |
| 589 | return start; |
| 590 | |
| 591 | case 1: |
| 592 | if ((end - start) < 1) |
| 593 | return NULL; |
| 594 | item->data.u8 = *start++; |
| 595 | return start; |
| 596 | |
| 597 | case 2: |
| 598 | if ((end - start) < 2) |
| 599 | return NULL; |
| 600 | item->data.u16 = le16_to_cpu(get_unaligned((__le16*)start)); |
| 601 | start = (__u8 *)((__le16 *)start + 1); |
| 602 | return start; |
| 603 | |
| 604 | case 3: |
| 605 | item->size++; |
| 606 | if ((end - start) < 4) |
| 607 | return NULL; |
| 608 | item->data.u32 = le32_to_cpu(get_unaligned((__le32*)start)); |
| 609 | start = (__u8 *)((__le32 *)start + 1); |
| 610 | return start; |
| 611 | } |
| 612 | |
| 613 | return NULL; |
| 614 | } |
| 615 | |
| 616 | /* |
| 617 | * Parse a report description into a hid_device structure. Reports are |
| 618 | * enumerated, fields are attached to these reports. |
| 619 | */ |
| 620 | |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 621 | struct hid_device *hid_parse_report(__u8 *start, unsigned size) |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 622 | { |
| 623 | struct hid_device *device; |
| 624 | struct hid_parser *parser; |
| 625 | struct hid_item item; |
| 626 | __u8 *end; |
| 627 | unsigned i; |
| 628 | static int (*dispatch_type[])(struct hid_parser *parser, |
| 629 | struct hid_item *item) = { |
| 630 | hid_parser_main, |
| 631 | hid_parser_global, |
| 632 | hid_parser_local, |
| 633 | hid_parser_reserved |
| 634 | }; |
| 635 | |
| 636 | if (!(device = kzalloc(sizeof(struct hid_device), GFP_KERNEL))) |
| 637 | return NULL; |
| 638 | |
| 639 | if (!(device->collection = kzalloc(sizeof(struct hid_collection) * |
| 640 | HID_DEFAULT_NUM_COLLECTIONS, GFP_KERNEL))) { |
| 641 | kfree(device); |
| 642 | return NULL; |
| 643 | } |
| 644 | device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; |
| 645 | |
| 646 | for (i = 0; i < HID_REPORT_TYPES; i++) |
| 647 | INIT_LIST_HEAD(&device->report_enum[i].report_list); |
| 648 | |
Ahmed S. Darwish | d6509c3 | 2007-01-06 15:18:52 +0200 | [diff] [blame] | 649 | if (!(device->rdesc = kmalloc(size, GFP_KERNEL))) { |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 650 | kfree(device->collection); |
| 651 | kfree(device); |
| 652 | return NULL; |
| 653 | } |
| 654 | memcpy(device->rdesc, start, size); |
| 655 | device->rsize = size; |
| 656 | |
| 657 | if (!(parser = kzalloc(sizeof(struct hid_parser), GFP_KERNEL))) { |
| 658 | kfree(device->rdesc); |
| 659 | kfree(device->collection); |
| 660 | kfree(device); |
| 661 | return NULL; |
| 662 | } |
| 663 | parser->device = device; |
| 664 | |
| 665 | end = start + size; |
| 666 | while ((start = fetch_item(start, end, &item)) != NULL) { |
| 667 | |
| 668 | if (item.format != HID_ITEM_FORMAT_SHORT) { |
| 669 | dbg("unexpected long global item"); |
| 670 | kfree(device->collection); |
| 671 | hid_free_device(device); |
| 672 | kfree(parser); |
| 673 | return NULL; |
| 674 | } |
| 675 | |
| 676 | if (dispatch_type[item.type](parser, &item)) { |
| 677 | dbg("item %u %u %u %u parsing failed\n", |
| 678 | item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag); |
| 679 | kfree(device->collection); |
| 680 | hid_free_device(device); |
| 681 | kfree(parser); |
| 682 | return NULL; |
| 683 | } |
| 684 | |
| 685 | if (start == end) { |
| 686 | if (parser->collection_stack_ptr) { |
| 687 | dbg("unbalanced collection at end of report description"); |
| 688 | kfree(device->collection); |
| 689 | hid_free_device(device); |
| 690 | kfree(parser); |
| 691 | return NULL; |
| 692 | } |
| 693 | if (parser->local.delimiter_depth) { |
| 694 | dbg("unbalanced delimiter at end of report description"); |
| 695 | kfree(device->collection); |
| 696 | hid_free_device(device); |
| 697 | kfree(parser); |
| 698 | return NULL; |
| 699 | } |
| 700 | kfree(parser); |
| 701 | return device; |
| 702 | } |
| 703 | } |
| 704 | |
| 705 | dbg("item fetching failed at offset %d\n", (int)(end - start)); |
| 706 | kfree(device->collection); |
| 707 | hid_free_device(device); |
| 708 | kfree(parser); |
| 709 | return NULL; |
| 710 | } |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 711 | EXPORT_SYMBOL_GPL(hid_parse_report); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 712 | |
| 713 | /* |
| 714 | * Convert a signed n-bit integer to signed 32-bit integer. Common |
| 715 | * cases are done through the compiler, the screwed things has to be |
| 716 | * done by hand. |
| 717 | */ |
| 718 | |
| 719 | static s32 snto32(__u32 value, unsigned n) |
| 720 | { |
| 721 | switch (n) { |
| 722 | case 8: return ((__s8)value); |
| 723 | case 16: return ((__s16)value); |
| 724 | case 32: return ((__s32)value); |
| 725 | } |
| 726 | return value & (1 << (n - 1)) ? value | (-1 << n) : value; |
| 727 | } |
| 728 | |
| 729 | /* |
| 730 | * Convert a signed 32-bit integer to a signed n-bit integer. |
| 731 | */ |
| 732 | |
| 733 | static u32 s32ton(__s32 value, unsigned n) |
| 734 | { |
| 735 | s32 a = value >> (n - 1); |
| 736 | if (a && a != -1) |
| 737 | return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; |
| 738 | return value & ((1 << n) - 1); |
| 739 | } |
| 740 | |
| 741 | /* |
| 742 | * Extract/implement a data field from/to a little endian report (bit array). |
| 743 | * |
| 744 | * Code sort-of follows HID spec: |
| 745 | * http://www.usb.org/developers/devclass_docs/HID1_11.pdf |
| 746 | * |
| 747 | * While the USB HID spec allows unlimited length bit fields in "report |
| 748 | * descriptors", most devices never use more than 16 bits. |
| 749 | * One model of UPS is claimed to report "LINEV" as a 32-bit field. |
| 750 | * Search linux-kernel and linux-usb-devel archives for "hid-core extract". |
| 751 | */ |
| 752 | |
| 753 | static __inline__ __u32 extract(__u8 *report, unsigned offset, unsigned n) |
| 754 | { |
| 755 | u64 x; |
| 756 | |
| 757 | WARN_ON(n > 32); |
| 758 | |
| 759 | report += offset >> 3; /* adjust byte index */ |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 760 | offset &= 7; /* now only need bit offset into one byte */ |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 761 | x = get_unaligned((u64 *) report); |
| 762 | x = le64_to_cpu(x); |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 763 | x = (x >> offset) & ((1ULL << n) - 1); /* extract bit field */ |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 764 | return (u32) x; |
| 765 | } |
| 766 | |
| 767 | /* |
| 768 | * "implement" : set bits in a little endian bit stream. |
| 769 | * Same concepts as "extract" (see comments above). |
| 770 | * The data mangled in the bit stream remains in little endian |
| 771 | * order the whole time. It make more sense to talk about |
| 772 | * endianness of register values by considering a register |
| 773 | * a "cached" copy of the little endiad bit stream. |
| 774 | */ |
| 775 | static __inline__ void implement(__u8 *report, unsigned offset, unsigned n, __u32 value) |
| 776 | { |
| 777 | u64 x; |
| 778 | u64 m = (1ULL << n) - 1; |
| 779 | |
| 780 | WARN_ON(n > 32); |
| 781 | |
| 782 | WARN_ON(value > m); |
| 783 | value &= m; |
| 784 | |
| 785 | report += offset >> 3; |
| 786 | offset &= 7; |
| 787 | |
| 788 | x = get_unaligned((u64 *)report); |
| 789 | x &= cpu_to_le64(~(m << offset)); |
| 790 | x |= cpu_to_le64(((u64) value) << offset); |
| 791 | put_unaligned(x, (u64 *) report); |
| 792 | } |
| 793 | |
| 794 | /* |
| 795 | * Search an array for a value. |
| 796 | */ |
| 797 | |
| 798 | static __inline__ int search(__s32 *array, __s32 value, unsigned n) |
| 799 | { |
| 800 | while (n--) { |
| 801 | if (*array++ == value) |
| 802 | return 0; |
| 803 | } |
| 804 | return -1; |
| 805 | } |
| 806 | |
| 807 | static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt) |
| 808 | { |
| 809 | hid_dump_input(usage, value); |
| 810 | if (hid->claimed & HID_CLAIMED_INPUT) |
| 811 | hidinput_hid_event(hid, field, usage, value); |
Jiri Kosina | aa938f7 | 2006-12-08 18:41:10 +0100 | [diff] [blame] | 812 | if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) |
| 813 | hid->hiddev_hid_event(hid, field, usage, value); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 814 | } |
| 815 | |
| 816 | /* |
| 817 | * Analyse a received field, and fetch the data from it. The field |
| 818 | * content is stored for next report processing (we do differential |
| 819 | * reporting to the layer). |
| 820 | */ |
| 821 | |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 822 | void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt) |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 823 | { |
| 824 | unsigned n; |
| 825 | unsigned count = field->report_count; |
| 826 | unsigned offset = field->report_offset; |
| 827 | unsigned size = field->report_size; |
| 828 | __s32 min = field->logical_minimum; |
| 829 | __s32 max = field->logical_maximum; |
| 830 | __s32 *value; |
| 831 | |
| 832 | if (!(value = kmalloc(sizeof(__s32) * count, GFP_ATOMIC))) |
| 833 | return; |
| 834 | |
| 835 | for (n = 0; n < count; n++) { |
| 836 | |
| 837 | value[n] = min < 0 ? snto32(extract(data, offset + n * size, size), size) : |
| 838 | extract(data, offset + n * size, size); |
| 839 | |
| 840 | if (!(field->flags & HID_MAIN_ITEM_VARIABLE) /* Ignore report if ErrorRollOver */ |
| 841 | && value[n] >= min && value[n] <= max |
| 842 | && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) |
| 843 | goto exit; |
| 844 | } |
| 845 | |
| 846 | for (n = 0; n < count; n++) { |
| 847 | |
| 848 | if (HID_MAIN_ITEM_VARIABLE & field->flags) { |
| 849 | hid_process_event(hid, field, &field->usage[n], value[n], interrupt); |
| 850 | continue; |
| 851 | } |
| 852 | |
| 853 | if (field->value[n] >= min && field->value[n] <= max |
| 854 | && field->usage[field->value[n] - min].hid |
| 855 | && search(value, field->value[n], count)) |
| 856 | hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); |
| 857 | |
| 858 | if (value[n] >= min && value[n] <= max |
| 859 | && field->usage[value[n] - min].hid |
| 860 | && search(field->value, value[n], count)) |
| 861 | hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); |
| 862 | } |
| 863 | |
| 864 | memcpy(field->value, value, count * sizeof(__s32)); |
| 865 | exit: |
| 866 | kfree(value); |
| 867 | } |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 868 | EXPORT_SYMBOL_GPL(hid_input_field); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 869 | |
| 870 | /* |
| 871 | * Output the field into the report. |
| 872 | */ |
| 873 | |
| 874 | static void hid_output_field(struct hid_field *field, __u8 *data) |
| 875 | { |
| 876 | unsigned count = field->report_count; |
| 877 | unsigned offset = field->report_offset; |
| 878 | unsigned size = field->report_size; |
| 879 | unsigned n; |
| 880 | |
Simon Budig | d4ae650 | 2007-01-15 17:28:47 +0100 | [diff] [blame] | 881 | /* make sure the unused bits in the last byte are zeros */ |
| 882 | if (count > 0 && size > 0) |
| 883 | data[(count*size-1)/8] = 0; |
| 884 | |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 885 | for (n = 0; n < count; n++) { |
| 886 | if (field->logical_minimum < 0) /* signed values */ |
| 887 | implement(data, offset + n * size, size, s32ton(field->value[n], size)); |
| 888 | else /* unsigned values */ |
| 889 | implement(data, offset + n * size, size, field->value[n]); |
| 890 | } |
| 891 | } |
| 892 | |
| 893 | /* |
| 894 | * Create a report. |
| 895 | */ |
| 896 | |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 897 | void hid_output_report(struct hid_report *report, __u8 *data) |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 898 | { |
| 899 | unsigned n; |
| 900 | |
| 901 | if (report->id > 0) |
| 902 | *data++ = report->id; |
| 903 | |
| 904 | for (n = 0; n < report->maxfield; n++) |
| 905 | hid_output_field(report->field[n], data); |
| 906 | } |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 907 | EXPORT_SYMBOL_GPL(hid_output_report); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 908 | |
| 909 | /* |
| 910 | * Set a field value. The report this field belongs to has to be |
| 911 | * created and transferred to the device, to set this value in the |
| 912 | * device. |
| 913 | */ |
| 914 | |
| 915 | int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) |
| 916 | { |
| 917 | unsigned size = field->report_size; |
| 918 | |
| 919 | hid_dump_input(field->usage + offset, value); |
| 920 | |
| 921 | if (offset >= field->report_count) { |
| 922 | dbg("offset (%d) exceeds report_count (%d)", offset, field->report_count); |
| 923 | hid_dump_field(field, 8); |
| 924 | return -1; |
| 925 | } |
| 926 | if (field->logical_minimum < 0) { |
| 927 | if (value != snto32(s32ton(value, size), size)) { |
| 928 | dbg("value %d is out of range", value); |
| 929 | return -1; |
| 930 | } |
| 931 | } |
| 932 | field->value[offset] = value; |
| 933 | return 0; |
| 934 | } |
Jiri Kosina | 229695e | 2006-12-08 18:40:53 +0100 | [diff] [blame] | 935 | EXPORT_SYMBOL_GPL(hid_set_field); |
Jiri Kosina | dde5845 | 2006-12-08 18:40:44 +0100 | [diff] [blame] | 936 | |
Jiri Kosina | aa8de2f | 2006-12-08 18:41:17 +0100 | [diff] [blame] | 937 | int hid_input_report(struct hid_device *hid, int type, u8 *data, int size, int interrupt) |
| 938 | { |
| 939 | struct hid_report_enum *report_enum = hid->report_enum + type; |
| 940 | struct hid_report *report; |
| 941 | int n, rsize; |
| 942 | |
| 943 | if (!hid) |
| 944 | return -ENODEV; |
| 945 | |
| 946 | if (!size) { |
| 947 | dbg("empty report"); |
| 948 | return -1; |
| 949 | } |
| 950 | |
Jiri Kosina | dd64c15 | 2007-01-30 16:02:24 +0100 | [diff] [blame] | 951 | #ifdef CONFIG_HID_DEBUG |
Jiri Kosina | e54dea6 | 2007-01-15 23:53:05 +0100 | [diff] [blame] | 952 | printk(KERN_DEBUG __FILE__ ": report (size %u) (%snumbered)\n", size, report_enum->numbered ? "" : "un"); |
Jiri Kosina | aa8de2f | 2006-12-08 18:41:17 +0100 | [diff] [blame] | 953 | #endif |
| 954 | |
| 955 | n = 0; /* Normally report number is 0 */ |
| 956 | if (report_enum->numbered) { /* Device uses numbered reports, data[0] is report number */ |
| 957 | n = *data++; |
| 958 | size--; |
| 959 | } |
| 960 | |
Jiri Kosina | dd64c15 | 2007-01-30 16:02:24 +0100 | [diff] [blame] | 961 | #ifdef CONFIG_HID_DEBUG |
Jiri Kosina | aa8de2f | 2006-12-08 18:41:17 +0100 | [diff] [blame] | 962 | { |
| 963 | int i; |
| 964 | printk(KERN_DEBUG __FILE__ ": report %d (size %u) = ", n, size); |
| 965 | for (i = 0; i < size; i++) |
| 966 | printk(" %02x", data[i]); |
| 967 | printk("\n"); |
| 968 | } |
| 969 | #endif |
| 970 | |
| 971 | if (!(report = report_enum->report_id_hash[n])) { |
| 972 | dbg("undefined report_id %d received", n); |
| 973 | return -1; |
| 974 | } |
| 975 | |
| 976 | rsize = ((report->size - 1) >> 3) + 1; |
| 977 | |
| 978 | if (size < rsize) { |
| 979 | dbg("report %d is too short, (%d < %d)", report->id, size, rsize); |
| 980 | return -1; |
| 981 | } |
| 982 | |
| 983 | if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) |
| 984 | hid->hiddev_report_event(hid, report); |
| 985 | |
| 986 | for (n = 0; n < report->maxfield; n++) |
| 987 | hid_input_field(hid, report->field[n], data, interrupt); |
| 988 | |
| 989 | if (hid->claimed & HID_CLAIMED_INPUT) |
| 990 | hidinput_report_event(hid, report); |
| 991 | |
| 992 | return 0; |
| 993 | } |
| 994 | EXPORT_SYMBOL_GPL(hid_input_report); |
| 995 | |
Jiri Kosina | aa938f7 | 2006-12-08 18:41:10 +0100 | [diff] [blame] | 996 | MODULE_LICENSE(DRIVER_LICENSE); |
| 997 | |