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
hid_clear_local(hid_item_t * c)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
hid_switch_rid(struct hid_data * s,struct hid_item * c,int32_t next_rID)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
hid_start_parse(report_desc_t d,int kindset,int id)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
hid_end_parse(hid_data_t s)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
hid_get_byte(struct hid_data * s,const uint16_t wSize)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
hid_get_item_raw(hid_data_t s,hid_item_t * h)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
hid_get_item(hid_data_t s,hid_item_t * h)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
hid_report_size(report_desc_t r,enum hid_kind k,int id)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
hid_locate(report_desc_t desc,unsigned int u,enum hid_kind k,hid_item_t * h,int id)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 }
581