lib/libu4bhid/parse.c

   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  * $FreeBSD: head/lib/libusbhid/parse.c 240762 2012-09-20 18:56:27Z mav $
  29  */
  30
  31 #include <assert.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <sys/time.h>
  35
  36 #include <bus/u4b/usb.h>
  37 #include <bus/u4b/usbhid.h>
  38
  39 #include "usbhid.h"
  40 #include "usbvar.h"
  41
  42 #define MAXUSAGE 100
  43 #define MAXPUSH 4
  44 #define MAXID 64
  45 #define ITEMTYPES 3
  46
  47 struct hid_pos_data {
  48         int32_t rid;
  49         uint32_t pos[ITEMTYPES];
  50 };
  51
  52 struct hid_data {
  53         const uint8_t *start;
  54         const uint8_t *end;
  55         const uint8_t *p;
  56         struct hid_item cur[MAXPUSH];
  57         struct hid_pos_data last_pos[MAXID];
  58         uint32_t pos[ITEMTYPES];
  59         int32_t usages_min[MAXUSAGE];
  60         int32_t usages_max[MAXUSAGE];
  61         int32_t usage_last;     /* last seen usage */
  62         uint32_t loc_size;      /* last seen size */
  63         uint32_t loc_count;     /* last seen count */
  64         uint8_t kindset;        /* we have 5 kinds so 8 bits are enough */
  65         uint8_t pushlevel;      /* current pushlevel */
  66         uint8_t ncount;         /* end usage item count */
  67         uint8_t icount;         /* current usage item count */
  68         uint8_t nusage;         /* end "usages_min/max" index */
  69         uint8_t iusage;         /* current "usages_min/max" index */
  70         uint8_t ousage;         /* current "usages_min/max" offset */
  71         uint8_t susage;         /* usage set flags */
  72         int32_t reportid;       /* requested report ID */
  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)
 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         s->reportid = id;
 162         return (s);
 163 }
 164
 165 /*------------------------------------------------------------------------*
 166  *      hid_end_parse
 167  *------------------------------------------------------------------------*/
 168 void
 169 hid_end_parse(hid_data_t s)
 170 {
 171
 172         if (s == NULL)
 173                 return;
 174
 175         free(s);
 176 }
 177
 178 /*------------------------------------------------------------------------*
 179  *      get byte from HID descriptor
 180  *------------------------------------------------------------------------*/
 181 static uint8_t
 182 hid_get_byte(struct hid_data *s, const uint16_t wSize)
 183 {
 184         const uint8_t *ptr;
 185         uint8_t retval;
 186
 187         ptr = s->p;
 188
 189         /* check if end is reached */
 190         if (ptr == s->end)
 191                 return (0);
 192
 193         /* read out a byte */
 194         retval = *ptr;
 195
 196         /* check if data pointer can be advanced by "wSize" bytes */
 197         if ((s->end - ptr) < wSize)
 198                 ptr = s->end;
 199         else
 200                 ptr += wSize;
 201
 202         /* update pointer */
 203         s->p = ptr;
 204
 205         return (retval);
 206 }
 207
 208 /*------------------------------------------------------------------------*
 209  *      hid_get_item
 210  *------------------------------------------------------------------------*/
 211 static int
 212 hid_get_item_raw(hid_data_t s, hid_item_t *h)
 213 {
 214         hid_item_t *c;
 215         unsigned int bTag, bType, bSize;
 216         int32_t mask;
 217         int32_t dval;
 218
 219         if (s == NULL)
 220                 return (0);
 221
 222         c = &s->cur[s->pushlevel];
 223
 224  top:
 225         /* check if there is an array of items */
 226         if (s->icount < s->ncount) {
 227                 /* get current usage */
 228                 if (s->iusage < s->nusage) {
 229                         dval = s->usages_min[s->iusage] + s->ousage;
 230                         c->usage = dval;
 231                         s->usage_last = dval;
 232                         if (dval == s->usages_max[s->iusage]) {
 233                                 s->iusage ++;
 234                                 s->ousage = 0;
 235                         } else {
 236                                 s->ousage ++;
 237                         }
 238                 } else {
 239                         /* Using last usage */
 240                         dval = s->usage_last;
 241                 }
 242                 s->icount ++;
 243                 /*
 244                  * Only copy HID item, increment position and return
 245                  * if correct kindset!
 246                  */
 247                 if (s->kindset & (1 << c->kind)) {
 248                         *h = *c;
 249                         h->pos = s->pos[c->kind];
 250                         s->pos[c->kind] += c->report_size * c->report_count;
 251                         return (1);
 252                 }
 253         }
 254
 255         /* reset state variables */
 256         s->icount = 0;
 257         s->ncount = 0;
 258         s->iusage = 0;
 259         s->nusage = 0;
 260         s->susage = 0;
 261         s->ousage = 0;
 262         hid_clear_local(c);
 263
 264         /* get next item */
 265         while (s->p != s->end) {
 266
 267                 bSize = hid_get_byte(s, 1);
 268                 if (bSize == 0xfe) {
 269                         /* long item */
 270                         bSize = hid_get_byte(s, 1);
 271                         bSize |= hid_get_byte(s, 1) << 8;
 272                         bTag = hid_get_byte(s, 1);
 273                         bType = 0xff;   /* XXX what should it be */
 274                 } else {
 275                         /* short item */
 276                         bTag = bSize >> 4;
 277                         bType = (bSize >> 2) & 3;
 278                         bSize &= 3;
 279                         if (bSize == 3)
 280                                 bSize = 4;
 281                 }
 282
 283                 switch(bSize) {
 284                 case 0:
 285                         dval = 0;
 286                         mask = 0;
 287                         break;
 288                 case 1:
 289                         dval = (int8_t)hid_get_byte(s, 1);
 290                         mask = 0xFF;
 291                         break;
 292                 case 2:
 293                         dval = hid_get_byte(s, 1);
 294                         dval |= hid_get_byte(s, 1) << 8;
 295                         dval = (int16_t)dval;
 296                         mask = 0xFFFF;
 297                         break;
 298                 case 4:
 299                         dval = hid_get_byte(s, 1);
 300                         dval |= hid_get_byte(s, 1) << 8;
 301                         dval |= hid_get_byte(s, 1) << 16;
 302                         dval |= hid_get_byte(s, 1) << 24;
 303                         mask = 0xFFFFFFFF;
 304                         break;
 305                 default:
 306                         dval = hid_get_byte(s, bSize);
 307                         continue;
 308                 }
 309
 310                 switch (bType) {
 311                 case 0:         /* Main */
 312                         switch (bTag) {
 313                         case 8: /* Input */
 314                                 c->kind = hid_input;
 315                                 c->flags = dval;
 316                 ret:
 317                                 c->report_count = s->loc_count;
 318                                 c->report_size = s->loc_size;
 319
 320                                 if (c->flags & HIO_VARIABLE) {
 321                                         /* range check usage count */
 322                                         if (c->report_count > 255) {
 323                                                 s->ncount = 255;
 324                                         } else
 325                                                 s->ncount = c->report_count;
 326
 327                                         /*
 328                                          * The "top" loop will return
 329                                          * one and one item:
 330                                          */
 331                                         c->report_count = 1;
 332                                         c->usage_minimum = 0;
 333                                         c->usage_maximum = 0;
 334                                 } else {
 335                                         s->ncount = 1;
 336                                 }
 337                                 goto top;
 338
 339                         case 9: /* Output */
 340                                 c->kind = hid_output;
 341                                 c->flags = dval;
 342                                 goto ret;
 343                         case 10:        /* Collection */
 344                                 c->kind = hid_collection;
 345                                 c->collection = dval;
 346                                 c->collevel++;
 347                                 c->usage = s->usage_last;
 348                                 *h = *c;
 349                                 return (1);
 350                         case 11:        /* Feature */
 351                                 c->kind = hid_feature;
 352                                 c->flags = dval;
 353                                 goto ret;
 354                         case 12:        /* End collection */
 355                                 c->kind = hid_endcollection;
 356                                 if (c->collevel == 0) {
 357                                         /* Invalid end collection. */
 358                                         return (0);
 359                                 }
 360                                 c->collevel--;
 361                                 *h = *c;
 362                                 return (1);
 363                         default:
 364                                 break;
 365                         }
 366                         break;
 367
 368                 case 1:         /* Global */
 369                         switch (bTag) {
 370                         case 0:
 371                                 c->_usage_page = dval << 16;
 372                                 break;
 373                         case 1:
 374                                 c->logical_minimum = dval;
 375                                 break;
 376                         case 2:
 377                                 c->logical_maximum = dval;
 378                                 break;
 379                         case 3:
 380                                 c->physical_minimum = dval;
 381                                 break;
 382                         case 4:
 383                                 c->physical_maximum = dval;
 384                                 break;
 385                         case 5:
 386                                 c->unit_exponent = dval;
 387                                 break;
 388                         case 6:
 389                                 c->unit = dval;
 390                                 break;
 391                         case 7:
 392                                 /* mask because value is unsigned */
 393                                 s->loc_size = dval & mask;
 394                                 break;
 395                         case 8:
 396                                 hid_switch_rid(s, c, dval & mask);
 397                                 break;
 398                         case 9:
 399                                 /* mask because value is unsigned */
 400                                 s->loc_count = dval & mask;
 401                                 break;
 402                         case 10:        /* Push */
 403                                 s->pushlevel ++;
 404                                 if (s->pushlevel < MAXPUSH) {
 405                                         s->cur[s->pushlevel] = *c;
 406                                         /* store size and count */
 407                                         c->report_size = s->loc_size;
 408                                         c->report_count = s->loc_count;
 409                                         /* update current item pointer */
 410                                         c = &s->cur[s->pushlevel];
 411                                 }
 412                                 break;
 413                         case 11:        /* Pop */
 414                                 s->pushlevel --;
 415                                 if (s->pushlevel < MAXPUSH) {
 416                                         c = &s->cur[s->pushlevel];
 417                                         /* restore size and count */
 418                                         s->loc_size = c->report_size;
 419                                         s->loc_count = c->report_count;
 420                                         c->report_size = 0;
 421                                         c->report_count = 0;
 422                                 }
 423                                 break;
 424                         default:
 425                                 break;
 426                         }
 427                         break;
 428                 case 2:         /* Local */
 429                         switch (bTag) {
 430                         case 0:
 431                                 if (bSize != 4)
 432                                         dval = (dval & mask) | c->_usage_page;
 433
 434                                 /* set last usage, in case of a collection */
 435                                 s->usage_last = dval;
 436
 437                                 if (s->nusage < MAXUSAGE) {
 438                                         s->usages_min[s->nusage] = dval;
 439                                         s->usages_max[s->nusage] = dval;
 440                                         s->nusage ++;
 441                                 }
 442                                 /* else XXX */
 443
 444                                 /* clear any pending usage sets */
 445                                 s->susage = 0;
 446                                 break;
 447                         case 1:
 448                                 s->susage |= 1;
 449
 450                                 if (bSize != 4)
 451                                         dval = (dval & mask) | c->_usage_page;
 452                                 c->usage_minimum = dval;
 453
 454                                 goto check_set;
 455                         case 2:
 456                                 s->susage |= 2;
 457
 458                                 if (bSize != 4)
 459                                         dval = (dval & mask) | c->_usage_page;
 460                                 c->usage_maximum = dval;
 461
 462                         check_set:
 463                                 if (s->susage != 3)
 464                                         break;
 465
 466                                 /* sanity check */
 467                                 if ((s->nusage < MAXUSAGE) &&
 468                                     (c->usage_minimum <= c->usage_maximum)) {
 469                                         /* add usage range */
 470                                         s->usages_min[s->nusage] =
 471                                             c->usage_minimum;
 472                                         s->usages_max[s->nusage] =
 473                                             c->usage_maximum;
 474                                         s->nusage ++;
 475                                 }
 476                                 /* else XXX */
 477
 478                                 s->susage = 0;
 479                                 break;
 480                         case 3:
 481                                 c->designator_index = dval;
 482                                 break;
 483                         case 4:
 484                                 c->designator_minimum = dval;
 485                                 break;
 486                         case 5:
 487                                 c->designator_maximum = dval;
 488                                 break;
 489                         case 7:
 490                                 c->string_index = dval;
 491                                 break;
 492                         case 8:
 493                                 c->string_minimum = dval;
 494                                 break;
 495                         case 9:
 496                                 c->string_maximum = dval;
 497                                 break;
 498                         case 10:
 499                                 c->set_delimiter = dval;
 500                                 break;
 501                         default:
 502                                 break;
 503                         }
 504                         break;
 505                 default:
 506                         break;
 507                 }
 508         }
 509         return (0);
 510 }
 511
 512 int
 513 hid_get_item(hid_data_t s, hid_item_t *h)
 514 {
 515         int r;
 516
 517         for (;;) {
 518                 r = hid_get_item_raw(s, h);
 519                 if (r <= 0 || s->reportid == -1 || h->report_ID == s->reportid)
 520                         break;
 521         }
 522         return (r);
 523 }
 524
 525 int
 526 hid_report_size(report_desc_t r, enum hid_kind k, int id)
 527 {
 528         struct hid_data *d;
 529         struct hid_item h;
 530         uint32_t temp;
 531         uint32_t hpos;
 532         uint32_t lpos;
 533         int report_id = 0;
 534
 535         hpos = 0;
 536         lpos = 0xFFFFFFFF;
 537
 538         memset(&h, 0, sizeof h);
 539         for (d = hid_start_parse(r, 1 << k, id); hid_get_item(d, &h); ) {
 540                 if (h.kind == k) {
 541                         /* compute minimum */
 542                         if (lpos > h.pos)
 543                                 lpos = h.pos;
 544                         /* compute end position */
 545                         temp = h.pos + (h.report_size * h.report_count);
 546                         /* compute maximum */
 547                         if (hpos < temp)
 548                                 hpos = temp;
 549                         if (h.report_ID != 0)
 550                                 report_id = 1;
 551                 }
 552         }
 553         hid_end_parse(d);
 554
 555         /* safety check - can happen in case of currupt descriptors */
 556         if (lpos > hpos)
 557                 temp = 0;
 558         else
 559                 temp = hpos - lpos;
 560
 561         /* return length in bytes rounded up */
 562         return ((temp + 7) / 8 + report_id);
 563 }
 564
 565 int
 566 hid_locate(report_desc_t desc, unsigned int u, enum hid_kind k,
 567            hid_item_t *h, int id)
 568 {
 569         struct hid_data *d;
 570
 571         for (d = hid_start_parse(desc, 1 << k, id); hid_get_item(d, h); ) {
 572                 if (h->kind == k && !(h->flags & HIO_CONST) && h->usage == u) {
 573                         hid_end_parse(d);
 574                         return (1);
 575                 }
 576         }
 577         hid_end_parse(d);
 578         h->report_size = 0;
 579         return (0);
 580 }