1 /* $NetBSD: parse.c,v 1.11 2000/09/24 02:19:54 augustss Exp $ */ 2 3 /* 4 * Copyright (c) 1999, 2001 Lennart Augustsson <augustss@netbsd.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <assert.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <sys/time.h> 36 37 #include <dev/usb/usb.h> 38 #include <dev/usb/usbhid.h> 39 40 #include "usbhid.h" 41 #include "usbvar.h" 42 43 #define MAXUSAGE 100 44 #define MAXPUSH 4 45 #define MAXID 64 46 #define ITEMTYPES 3 47 48 struct hid_pos_data { 49 int32_t rid; 50 uint32_t pos[ITEMTYPES]; 51 }; 52 53 struct hid_data { 54 const uint8_t *start; 55 const uint8_t *end; 56 const uint8_t *p; 57 struct hid_item cur[MAXPUSH]; 58 struct hid_pos_data last_pos[MAXID]; 59 uint32_t pos[ITEMTYPES]; 60 int32_t usages_min[MAXUSAGE]; 61 int32_t usages_max[MAXUSAGE]; 62 int32_t usage_last; /* last seen usage */ 63 uint32_t loc_size; /* last seen size */ 64 uint32_t loc_count; /* last seen count */ 65 uint8_t kindset; /* we have 5 kinds so 8 bits are enough */ 66 uint8_t pushlevel; /* current pushlevel */ 67 uint8_t ncount; /* end usage item count */ 68 uint8_t icount; /* current usage item count */ 69 uint8_t nusage; /* end "usages_min/max" index */ 70 uint8_t iusage; /* current "usages_min/max" index */ 71 uint8_t ousage; /* current "usages_min/max" offset */ 72 uint8_t susage; /* usage set flags */ 73 }; 74 75 /*------------------------------------------------------------------------* 76 * hid_clear_local 77 *------------------------------------------------------------------------*/ 78 static void 79 hid_clear_local(hid_item_t *c) 80 { 81 82 c->usage = 0; 83 c->usage_minimum = 0; 84 c->usage_maximum = 0; 85 c->designator_index = 0; 86 c->designator_minimum = 0; 87 c->designator_maximum = 0; 88 c->string_index = 0; 89 c->string_minimum = 0; 90 c->string_maximum = 0; 91 c->set_delimiter = 0; 92 } 93 94 static void 95 hid_switch_rid(struct hid_data *s, struct hid_item *c, int32_t next_rID) 96 { 97 uint8_t i, j; 98 99 /* check for same report ID - optimise */ 100 101 if (c->report_ID == next_rID) 102 return; 103 104 /* save current position for current rID */ 105 106 if (c->report_ID == 0) { 107 i = 0; 108 } else { 109 for (i = 1; i != MAXID; i++) { 110 if (s->last_pos[i].rid == c->report_ID) 111 break; 112 if (s->last_pos[i].rid == 0) 113 break; 114 } 115 } 116 if (i != MAXID) { 117 s->last_pos[i].rid = c->report_ID; 118 for (j = 0; j < ITEMTYPES; j++) 119 s->last_pos[i].pos[j] = s->pos[j]; 120 } 121 122 /* store next report ID */ 123 124 c->report_ID = next_rID; 125 126 /* lookup last position for next rID */ 127 128 if (next_rID == 0) { 129 i = 0; 130 } else { 131 for (i = 1; i != MAXID; i++) { 132 if (s->last_pos[i].rid == next_rID) 133 break; 134 if (s->last_pos[i].rid == 0) 135 break; 136 } 137 } 138 if (i != MAXID) { 139 s->last_pos[i].rid = next_rID; 140 for (j = 0; j < ITEMTYPES; j++) 141 s->pos[j] = s->last_pos[i].pos[j]; 142 } else { 143 for (j = 0; j < ITEMTYPES; j++) 144 s->pos[j] = 0; /* Out of RID entries. */ 145 } 146 } 147 148 /*------------------------------------------------------------------------* 149 * hid_start_parse 150 *------------------------------------------------------------------------*/ 151 hid_data_t 152 hid_start_parse(report_desc_t d, int kindset, int id __unused) 153 { 154 struct hid_data *s; 155 156 s = malloc(sizeof *s); 157 memset(s, 0, sizeof *s); 158 s->start = s->p = d->data; 159 s->end = d->data + d->size; 160 s->kindset = kindset; 161 return (s); 162 } 163 164 /*------------------------------------------------------------------------* 165 * hid_end_parse 166 *------------------------------------------------------------------------*/ 167 void 168 hid_end_parse(hid_data_t s) 169 { 170 171 if (s == NULL) 172 return; 173 174 free(s); 175 } 176 177 /*------------------------------------------------------------------------* 178 * get byte from HID descriptor 179 *------------------------------------------------------------------------*/ 180 static uint8_t 181 hid_get_byte(struct hid_data *s, const uint16_t wSize) 182 { 183 const uint8_t *ptr; 184 uint8_t retval; 185 186 ptr = s->p; 187 188 /* check if end is reached */ 189 if (ptr == s->end) 190 return (0); 191 192 /* read out a byte */ 193 retval = *ptr; 194 195 /* check if data pointer can be advanced by "wSize" bytes */ 196 if ((s->end - ptr) < wSize) 197 ptr = s->end; 198 else 199 ptr += wSize; 200 201 /* update pointer */ 202 s->p = ptr; 203 204 return (retval); 205 } 206 207 /*------------------------------------------------------------------------* 208 * hid_get_item 209 *------------------------------------------------------------------------*/ 210 int 211 hid_get_item(hid_data_t s, hid_item_t *h) 212 { 213 hid_item_t *c; 214 unsigned int bTag, bType, bSize; 215 int32_t mask; 216 int32_t dval; 217 218 if (s == NULL) 219 return (0); 220 221 c = &s->cur[s->pushlevel]; 222 223 top: 224 /* check if there is an array of items */ 225 if (s->icount < s->ncount) { 226 /* get current usage */ 227 if (s->iusage < s->nusage) { 228 dval = s->usages_min[s->iusage] + s->ousage; 229 c->usage = dval; 230 s->usage_last = dval; 231 if (dval == s->usages_max[s->iusage]) { 232 s->iusage ++; 233 s->ousage = 0; 234 } else { 235 s->ousage ++; 236 } 237 } else { 238 /* Using last usage */ 239 dval = s->usage_last; 240 } 241 s->icount ++; 242 /* 243 * Only copy HID item, increment position and return 244 * if correct kindset! 245 */ 246 if (s->kindset & (1 << c->kind)) { 247 *h = *c; 248 h->pos = s->pos[c->kind]; 249 s->pos[c->kind] += c->report_size * c->report_count; 250 return (1); 251 } 252 } 253 254 /* reset state variables */ 255 s->icount = 0; 256 s->ncount = 0; 257 s->iusage = 0; 258 s->nusage = 0; 259 s->susage = 0; 260 s->ousage = 0; 261 hid_clear_local(c); 262 263 /* get next item */ 264 while (s->p != s->end) { 265 266 bSize = hid_get_byte(s, 1); 267 if (bSize == 0xfe) { 268 /* long item */ 269 bSize = hid_get_byte(s, 1); 270 bSize |= hid_get_byte(s, 1) << 8; 271 bTag = hid_get_byte(s, 1); 272 bType = 0xff; /* XXX what should it be */ 273 } else { 274 /* short item */ 275 bTag = bSize >> 4; 276 bType = (bSize >> 2) & 3; 277 bSize &= 3; 278 if (bSize == 3) 279 bSize = 4; 280 } 281 282 switch(bSize) { 283 case 0: 284 dval = 0; 285 mask = 0; 286 break; 287 case 1: 288 dval = (int8_t)hid_get_byte(s, 1); 289 mask = 0xFF; 290 break; 291 case 2: 292 dval = hid_get_byte(s, 1); 293 dval |= hid_get_byte(s, 1) << 8; 294 dval = (int16_t)dval; 295 mask = 0xFFFF; 296 break; 297 case 4: 298 dval = hid_get_byte(s, 1); 299 dval |= hid_get_byte(s, 1) << 8; 300 dval |= hid_get_byte(s, 1) << 16; 301 dval |= hid_get_byte(s, 1) << 24; 302 mask = 0xFFFFFFFF; 303 break; 304 default: 305 dval = hid_get_byte(s, bSize); 306 continue; 307 } 308 309 switch (bType) { 310 case 0: /* Main */ 311 switch (bTag) { 312 case 8: /* Input */ 313 c->kind = hid_input; 314 c->flags = dval; 315 ret: 316 c->report_count = s->loc_count; 317 c->report_size = s->loc_size; 318 319 if (c->flags & HIO_VARIABLE) { 320 /* range check usage count */ 321 if (c->report_count > 255) { 322 s->ncount = 255; 323 } else 324 s->ncount = c->report_count; 325 326 /* 327 * The "top" loop will return 328 * one and one item: 329 */ 330 c->report_count = 1; 331 c->usage_minimum = 0; 332 c->usage_maximum = 0; 333 } else { 334 s->ncount = 1; 335 } 336 goto top; 337 338 case 9: /* Output */ 339 c->kind = hid_output; 340 c->flags = dval; 341 goto ret; 342 case 10: /* Collection */ 343 c->kind = hid_collection; 344 c->collection = dval; 345 c->collevel++; 346 c->usage = s->usage_last; 347 *h = *c; 348 return (1); 349 case 11: /* Feature */ 350 c->kind = hid_feature; 351 c->flags = dval; 352 goto ret; 353 case 12: /* End collection */ 354 c->kind = hid_endcollection; 355 if (c->collevel == 0) { 356 /* Invalid end collection. */ 357 return (0); 358 } 359 c->collevel--; 360 *h = *c; 361 return (1); 362 default: 363 break; 364 } 365 break; 366 367 case 1: /* Global */ 368 switch (bTag) { 369 case 0: 370 c->_usage_page = dval << 16; 371 break; 372 case 1: 373 c->logical_minimum = dval; 374 break; 375 case 2: 376 c->logical_maximum = dval; 377 break; 378 case 3: 379 c->physical_minimum = dval; 380 break; 381 case 4: 382 c->physical_maximum = dval; 383 break; 384 case 5: 385 c->unit_exponent = dval; 386 break; 387 case 6: 388 c->unit = dval; 389 break; 390 case 7: 391 /* mask because value is unsigned */ 392 s->loc_size = dval & mask; 393 break; 394 case 8: 395 hid_switch_rid(s, c, dval); 396 break; 397 case 9: 398 /* mask because value is unsigned */ 399 s->loc_count = dval & mask; 400 break; 401 case 10: /* Push */ 402 s->pushlevel ++; 403 if (s->pushlevel < MAXPUSH) { 404 s->cur[s->pushlevel] = *c; 405 /* store size and count */ 406 c->report_size = s->loc_size; 407 c->report_count = s->loc_count; 408 /* update current item pointer */ 409 c = &s->cur[s->pushlevel]; 410 } 411 break; 412 case 11: /* Pop */ 413 s->pushlevel --; 414 if (s->pushlevel < MAXPUSH) { 415 c = &s->cur[s->pushlevel]; 416 /* restore size and count */ 417 s->loc_size = c->report_size; 418 s->loc_count = c->report_count; 419 c->report_size = 0; 420 c->report_count = 0; 421 } 422 break; 423 default: 424 break; 425 } 426 break; 427 case 2: /* Local */ 428 switch (bTag) { 429 case 0: 430 if (bSize != 4) 431 dval = (dval & mask) | c->_usage_page; 432 433 /* set last usage, in case of a collection */ 434 s->usage_last = dval; 435 436 if (s->nusage < MAXUSAGE) { 437 s->usages_min[s->nusage] = dval; 438 s->usages_max[s->nusage] = dval; 439 s->nusage ++; 440 } 441 /* else XXX */ 442 443 /* clear any pending usage sets */ 444 s->susage = 0; 445 break; 446 case 1: 447 s->susage |= 1; 448 449 if (bSize != 4) 450 dval = (dval & mask) | c->_usage_page; 451 c->usage_minimum = dval; 452 453 goto check_set; 454 case 2: 455 s->susage |= 2; 456 457 if (bSize != 4) 458 dval = (dval & mask) | c->_usage_page; 459 c->usage_maximum = dval; 460 461 check_set: 462 if (s->susage != 3) 463 break; 464 465 /* sanity check */ 466 if ((s->nusage < MAXUSAGE) && 467 (c->usage_minimum <= c->usage_maximum)) { 468 /* add usage range */ 469 s->usages_min[s->nusage] = 470 c->usage_minimum; 471 s->usages_max[s->nusage] = 472 c->usage_maximum; 473 s->nusage ++; 474 } 475 /* else XXX */ 476 477 s->susage = 0; 478 break; 479 case 3: 480 c->designator_index = dval; 481 break; 482 case 4: 483 c->designator_minimum = dval; 484 break; 485 case 5: 486 c->designator_maximum = dval; 487 break; 488 case 7: 489 c->string_index = dval; 490 break; 491 case 8: 492 c->string_minimum = dval; 493 break; 494 case 9: 495 c->string_maximum = dval; 496 break; 497 case 10: 498 c->set_delimiter = dval; 499 break; 500 default: 501 break; 502 } 503 break; 504 default: 505 break; 506 } 507 } 508 return (0); 509 } 510 511 int 512 hid_report_size(report_desc_t r, enum hid_kind k, int id) 513 { 514 struct hid_data *d; 515 struct hid_item h; 516 uint32_t temp; 517 uint32_t hpos; 518 uint32_t lpos; 519 int report_id = 0; 520 521 hpos = 0; 522 lpos = 0xFFFFFFFF; 523 524 memset(&h, 0, sizeof h); 525 for (d = hid_start_parse(r, 1 << k, id); hid_get_item(d, &h); ) { 526 if ((h.report_ID == id || id < 0) && h.kind == k) { 527 /* compute minimum */ 528 if (lpos > h.pos) 529 lpos = h.pos; 530 /* compute end position */ 531 temp = h.pos + (h.report_size * h.report_count); 532 /* compute maximum */ 533 if (hpos < temp) 534 hpos = temp; 535 if (h.report_ID != 0) 536 report_id = 1; 537 } 538 } 539 hid_end_parse(d); 540 541 /* safety check - can happen in case of currupt descriptors */ 542 if (lpos > hpos) 543 temp = 0; 544 else 545 temp = hpos - lpos; 546 547 /* return length in bytes rounded up */ 548 return ((temp + 7) / 8 + report_id); 549 } 550 551 int 552 hid_locate(report_desc_t desc, unsigned int u, enum hid_kind k, 553 hid_item_t *h, int id) 554 { 555 struct hid_data *d; 556 557 for (d = hid_start_parse(desc, 1 << k, id); hid_get_item(d, h); ) { 558 if (h->kind == k && !(h->flags & HIO_CONST) && h->usage == u) { 559 hid_end_parse(d); 560 return (1); 561 } 562 } 563 hid_end_parse(d); 564 h->report_size = 0; 565 return (0); 566 } 567