xref: /freebsd/sys/dev/hid/hidbus.c (revision 18250ec6c089c0c50cbd9fd87d78e03ff89916df)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019-2020 Vladimir Kondratyev <wulf@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/ck.h>
31 #include <sys/epoch.h>
32 #include <sys/kdb.h>
33 #include <sys/kernel.h>
34 #include <sys/libkern.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/proc.h>
40 #include <sys/sbuf.h>
41 #include <sys/sx.h>
42 #include <sys/systm.h>
43 
44 #define	HID_DEBUG_VAR	hid_debug
45 #include <dev/hid/hid.h>
46 #include <dev/hid/hidbus.h>
47 #include <dev/hid/hidquirk.h>
48 
49 #include "hid_if.h"
50 
51 #define	INPUT_EPOCH	global_epoch_preempt
52 #define	HID_RSIZE_MAX	1024
53 
54 static hid_intr_t	hidbus_intr;
55 
56 static device_probe_t	hidbus_probe;
57 static device_attach_t	hidbus_attach;
58 static device_detach_t	hidbus_detach;
59 
60 struct hidbus_ivars {
61 	int32_t				usage;
62 	uint8_t				index;
63 	uint32_t			flags;
64 	uintptr_t			driver_info;    /* for internal use */
65 	struct mtx			*mtx;		/* child intr mtx */
66 	hid_intr_t			*intr_handler;	/* executed under mtx*/
67 	void				*intr_ctx;
68 	unsigned int			refcnt;		/* protected by mtx */
69 	struct epoch_context		epoch_ctx;
70 	CK_STAILQ_ENTRY(hidbus_ivars)	link;
71 };
72 
73 struct hidbus_softc {
74 	device_t			dev;
75 	struct sx			sx;
76 	struct mtx			mtx;
77 
78 	bool				nowrite;
79 
80 	struct hid_rdesc_info		rdesc;
81 	bool				overloaded;
82 	int				nest;	/* Child attach nesting lvl */
83 	int				nauto;	/* Number of autochildren */
84 
85 	CK_STAILQ_HEAD(, hidbus_ivars)	tlcs;
86 };
87 
88 static int
89 hidbus_fill_rdesc_info(struct hid_rdesc_info *hri, const void *data,
90     hid_size_t len)
91 {
92 	int error = 0;
93 
94 	hri->data = __DECONST(void *, data);
95 	hri->len = len;
96 
97 	/*
98 	 * If report descriptor is not available yet, set maximal
99 	 * report sizes high enough to allow hidraw to work.
100 	 */
101 	hri->isize = len == 0 ? HID_RSIZE_MAX :
102 	    hid_report_size_max(data, len, hid_input, &hri->iid);
103 	hri->osize = len == 0 ? HID_RSIZE_MAX :
104 	    hid_report_size_max(data, len, hid_output, &hri->oid);
105 	hri->fsize = len == 0 ? HID_RSIZE_MAX :
106 	    hid_report_size_max(data, len, hid_feature, &hri->fid);
107 
108 	if (hri->isize > HID_RSIZE_MAX) {
109 		DPRINTF("input size is too large, %u bytes (truncating)\n",
110 		    hri->isize);
111 		hri->isize = HID_RSIZE_MAX;
112 		error = EOVERFLOW;
113 	}
114 	if (hri->osize > HID_RSIZE_MAX) {
115 		DPRINTF("output size is too large, %u bytes (truncating)\n",
116 		    hri->osize);
117 		hri->osize = HID_RSIZE_MAX;
118 		error = EOVERFLOW;
119 	}
120 	if (hri->fsize > HID_RSIZE_MAX) {
121 		DPRINTF("feature size is too large, %u bytes (truncating)\n",
122 		    hri->fsize);
123 		hri->fsize = HID_RSIZE_MAX;
124 		error = EOVERFLOW;
125 	}
126 
127 	return (error);
128 }
129 
130 int
131 hidbus_locate(const void *desc, hid_size_t size, int32_t u, enum hid_kind k,
132     uint8_t tlc_index, uint8_t index, struct hid_location *loc,
133     uint32_t *flags, uint8_t *id, struct hid_absinfo *ai)
134 {
135 	struct hid_data *d;
136 	struct hid_item h;
137 	int i;
138 
139 	d = hid_start_parse(desc, size, 1 << k);
140 	HIDBUS_FOREACH_ITEM(d, &h, tlc_index) {
141 		for (i = 0; i < h.nusages; i++) {
142 			if (h.kind == k && h.usages[i] == u) {
143 				if (index--)
144 					break;
145 				if (loc != NULL)
146 					*loc = h.loc;
147 				if (flags != NULL)
148 					*flags = h.flags;
149 				if (id != NULL)
150 					*id = h.report_ID;
151 				if (ai != NULL && (h.flags&HIO_RELATIVE) == 0)
152 					*ai = (struct hid_absinfo) {
153 					    .max = h.logical_maximum,
154 					    .min = h.logical_minimum,
155 					    .res = hid_item_resolution(&h),
156 					};
157 				hid_end_parse(d);
158 				return (1);
159 			}
160 		}
161 	}
162 	if (loc != NULL)
163 		loc->size = 0;
164 	if (flags != NULL)
165 		*flags = 0;
166 	if (id != NULL)
167 		*id = 0;
168 	hid_end_parse(d);
169 	return (0);
170 }
171 
172 bool
173 hidbus_is_collection(const void *desc, hid_size_t size, int32_t usage,
174     uint8_t tlc_index)
175 {
176 	struct hid_data *d;
177 	struct hid_item h;
178 	bool ret = false;
179 
180 	d = hid_start_parse(desc, size, 0);
181 	HIDBUS_FOREACH_ITEM(d, &h, tlc_index) {
182 		if (h.kind == hid_collection && h.usage == usage) {
183 			ret = true;
184 			break;
185 		}
186 	}
187 	hid_end_parse(d);
188 	return (ret);
189 }
190 
191 static device_t
192 hidbus_add_child(device_t dev, u_int order, const char *name, int unit)
193 {
194 	struct hidbus_softc *sc = device_get_softc(dev);
195 	struct hidbus_ivars *tlc;
196 	device_t child;
197 
198 	child = device_add_child_ordered(dev, order, name, unit);
199 	if (child == NULL)
200 			return (child);
201 
202 	tlc = malloc(sizeof(struct hidbus_ivars), M_DEVBUF, M_WAITOK | M_ZERO);
203 	tlc->mtx = &sc->mtx;
204 	device_set_ivars(child, tlc);
205 	sx_xlock(&sc->sx);
206 	CK_STAILQ_INSERT_TAIL(&sc->tlcs, tlc, link);
207 	sx_unlock(&sc->sx);
208 
209 	return (child);
210 }
211 
212 static int
213 hidbus_enumerate_children(device_t dev, const void* data, hid_size_t len)
214 {
215 	struct hidbus_softc *sc = device_get_softc(dev);
216 	struct hid_data *hd;
217 	struct hid_item hi;
218 	device_t child;
219 	uint8_t index = 0;
220 
221 	if (data == NULL || len == 0)
222 		return (ENXIO);
223 
224 	/* Add a child for each top level collection */
225 	hd = hid_start_parse(data, len, 1 << hid_input);
226 	while (hid_get_item(hd, &hi)) {
227 		if (hi.kind != hid_collection || hi.collevel != 1)
228 			continue;
229 		child = BUS_ADD_CHILD(dev, 0, NULL, DEVICE_UNIT_ANY);
230 		if (child == NULL) {
231 			device_printf(dev, "Could not add HID device\n");
232 			continue;
233 		}
234 		hidbus_set_index(child, index);
235 		hidbus_set_usage(child, hi.usage);
236 		hidbus_set_flags(child, HIDBUS_FLAG_AUTOCHILD);
237 		index++;
238 		DPRINTF("Add child TLC: 0x%04x:0x%04x\n",
239 		    HID_GET_USAGE_PAGE(hi.usage), HID_GET_USAGE(hi.usage));
240 	}
241 	hid_end_parse(hd);
242 
243 	if (index == 0)
244 		return (ENXIO);
245 
246 	sc->nauto = index;
247 
248 	return (0);
249 }
250 
251 static int
252 hidbus_attach_children(device_t dev)
253 {
254 	struct hidbus_softc *sc = device_get_softc(dev);
255 	int error;
256 
257 	HID_INTR_SETUP(device_get_parent(dev), dev, hidbus_intr, sc,
258 	    &sc->rdesc);
259 
260 	error = hidbus_enumerate_children(dev, sc->rdesc.data, sc->rdesc.len);
261 	if (error != 0)
262 		DPRINTF("failed to enumerate children: error %d\n", error);
263 
264 	/*
265 	 * hidbus_attach_children() can recurse through device_identify->
266 	 * hid_set_report_descr() call sequence. Do not perform children
267 	 * attach twice in that case.
268 	 */
269 	sc->nest++;
270 	bus_identify_children(dev);
271 	sc->nest--;
272 	if (sc->nest != 0)
273 		return (0);
274 
275 	if (hid_is_keyboard(sc->rdesc.data, sc->rdesc.len) != 0) {
276 		bus_attach_children(dev);
277 		error = 0;
278 	} else
279 		error = bus_delayed_attach_children(dev);
280 	if (error != 0)
281 		device_printf(dev, "failed to attach child: error %d\n", error);
282 
283 	return (error);
284 }
285 
286 static int
287 hidbus_detach_children(device_t dev)
288 {
289 	device_t *children, bus;
290 	bool is_bus;
291 	int i, error;
292 
293 	error = 0;
294 
295 	is_bus = device_get_devclass(dev) == devclass_find("hidbus");
296 	bus = is_bus ? dev : device_get_parent(dev);
297 
298 	KASSERT(device_get_devclass(bus) == devclass_find("hidbus"),
299 	    ("Device is not hidbus or it's child"));
300 
301 	if (is_bus) {
302 		/* If hidbus is passed, delete all children. */
303 		bus_generic_detach(bus);
304 		device_delete_children(bus);
305 	} else {
306 		/*
307 		 * If hidbus child is passed, delete all hidbus children
308 		 * except caller. Deleting the caller may result in deadlock.
309 		 */
310 		error = device_get_children(bus, &children, &i);
311 		if (error != 0)
312 			return (error);
313 		while (i-- > 0) {
314 			if (children[i] == dev)
315 				continue;
316 			DPRINTF("Delete child. index=%d (%s)\n",
317 			    hidbus_get_index(children[i]),
318 			    device_get_nameunit(children[i]));
319 			error = device_delete_child(bus, children[i]);
320 			if (error) {
321 				DPRINTF("Failed deleting %s\n",
322 				    device_get_nameunit(children[i]));
323 				break;
324 			}
325 		}
326 		free(children, M_TEMP);
327 	}
328 
329 	HID_INTR_UNSETUP(device_get_parent(bus), bus);
330 
331 	return (error);
332 }
333 
334 static int
335 hidbus_probe(device_t dev)
336 {
337 
338 	device_set_desc(dev, "HID bus");
339 
340 	/* Allow other subclasses to override this driver. */
341 	return (BUS_PROBE_GENERIC);
342 }
343 
344 static int
345 hidbus_attach(device_t dev)
346 {
347 	struct hidbus_softc *sc = device_get_softc(dev);
348 	struct hid_device_info *devinfo = device_get_ivars(dev);
349 	void *d_ptr = NULL;
350 	hid_size_t d_len;
351 	int error;
352 
353 	sc->dev = dev;
354 	CK_STAILQ_INIT(&sc->tlcs);
355 	mtx_init(&sc->mtx, "hidbus ivar lock", NULL, MTX_DEF);
356 	sx_init(&sc->sx, "hidbus ivar list lock");
357 
358 	/*
359 	 * Ignore error. It is possible for non-HID device e.g. XBox360 gamepad
360 	 * to emulate HID through overloading of report descriptor.
361 	 */
362 	d_len = devinfo->rdescsize;
363 	if (d_len != 0) {
364 		d_ptr = malloc(d_len, M_DEVBUF, M_ZERO | M_WAITOK);
365 		error = hid_get_rdesc(dev, d_ptr, d_len);
366 		if (error != 0) {
367 			free(d_ptr, M_DEVBUF);
368 			d_len = 0;
369 			d_ptr = NULL;
370 		}
371 	}
372 
373 	hidbus_fill_rdesc_info(&sc->rdesc, d_ptr, d_len);
374 
375 	sc->nowrite = hid_test_quirk(devinfo, HQ_NOWRITE);
376 
377 	error = hidbus_attach_children(dev);
378 	if (error != 0) {
379 		hidbus_detach(dev);
380 		return (ENXIO);
381 	}
382 
383 	return (0);
384 }
385 
386 static int
387 hidbus_detach(device_t dev)
388 {
389 	struct hidbus_softc *sc = device_get_softc(dev);
390 
391 	hidbus_detach_children(dev);
392 	sx_destroy(&sc->sx);
393 	mtx_destroy(&sc->mtx);
394 	free(sc->rdesc.data, M_DEVBUF);
395 
396 	return (0);
397 }
398 
399 static void
400 hidbus_child_detached(device_t bus, device_t child)
401 {
402 	struct hidbus_softc *sc = device_get_softc(bus);
403 	struct hidbus_ivars *tlc = device_get_ivars(child);
404 
405 	KASSERT(tlc->refcnt == 0, ("Child device is running"));
406 	tlc->mtx = &sc->mtx;
407 	tlc->intr_handler = NULL;
408 	tlc->flags &= ~HIDBUS_FLAG_CAN_POLL;
409 }
410 
411 /*
412  * Epoch callback indicating tlc is safe to destroy
413  */
414 static void
415 hidbus_ivar_dtor(epoch_context_t ctx)
416 {
417 	struct hidbus_ivars *tlc;
418 
419 	tlc = __containerof(ctx, struct hidbus_ivars, epoch_ctx);
420 	free(tlc, M_DEVBUF);
421 }
422 
423 static void
424 hidbus_child_deleted(device_t bus, device_t child)
425 {
426 	struct hidbus_softc *sc = device_get_softc(bus);
427 	struct hidbus_ivars *tlc = device_get_ivars(child);
428 
429 	sx_xlock(&sc->sx);
430 	KASSERT(tlc->refcnt == 0, ("Child device is running"));
431 	CK_STAILQ_REMOVE(&sc->tlcs, tlc, hidbus_ivars, link);
432 	sx_unlock(&sc->sx);
433 	epoch_call(INPUT_EPOCH, hidbus_ivar_dtor, &tlc->epoch_ctx);
434 }
435 
436 static int
437 hidbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
438 {
439 	struct hidbus_softc *sc = device_get_softc(bus);
440 	struct hidbus_ivars *tlc = device_get_ivars(child);
441 
442 	switch (which) {
443 	case HIDBUS_IVAR_INDEX:
444 		*result = tlc->index;
445 		break;
446 	case HIDBUS_IVAR_USAGE:
447 		*result = tlc->usage;
448 		break;
449 	case HIDBUS_IVAR_FLAGS:
450 		*result = tlc->flags;
451 		break;
452 	case HIDBUS_IVAR_DRIVER_INFO:
453 		*result = tlc->driver_info;
454 		break;
455 	case HIDBUS_IVAR_LOCK:
456 		*result = (uintptr_t)(tlc->mtx == &sc->mtx ? NULL : tlc->mtx);
457 		break;
458 	default:
459 		return (EINVAL);
460 	}
461 	return (0);
462 }
463 
464 static int
465 hidbus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
466 {
467 	struct hidbus_softc *sc = device_get_softc(bus);
468 	struct hidbus_ivars *tlc = device_get_ivars(child);
469 
470 	switch (which) {
471 	case HIDBUS_IVAR_INDEX:
472 		tlc->index = value;
473 		break;
474 	case HIDBUS_IVAR_USAGE:
475 		tlc->usage = value;
476 		break;
477 	case HIDBUS_IVAR_FLAGS:
478 		tlc->flags = value;
479 		if ((value & HIDBUS_FLAG_CAN_POLL) != 0)
480 			HID_INTR_SETUP(
481 			    device_get_parent(bus), bus, NULL, NULL, NULL);
482 		break;
483 	case HIDBUS_IVAR_DRIVER_INFO:
484 		tlc->driver_info = value;
485 		break;
486 	case HIDBUS_IVAR_LOCK:
487 		tlc->mtx = (struct mtx *)value == NULL ?
488 		    &sc->mtx : (struct mtx *)value;
489 		break;
490 	default:
491 		return (EINVAL);
492 	}
493 	return (0);
494 }
495 
496 /* Location hint for devctl(8) */
497 static int
498 hidbus_child_location(device_t bus, device_t child, struct sbuf *sb)
499 {
500 	struct hidbus_ivars *tlc = device_get_ivars(child);
501 
502 	sbuf_printf(sb, "index=%hhu", tlc->index);
503         return (0);
504 }
505 
506 /* PnP information for devctl(8) */
507 static int
508 hidbus_child_pnpinfo(device_t bus, device_t child, struct sbuf *sb)
509 {
510 	struct hidbus_ivars *tlc = device_get_ivars(child);
511 	struct hid_device_info *devinfo = device_get_ivars(bus);
512 
513 	sbuf_printf(sb, "page=0x%04x usage=0x%04x bus=0x%02hx "
514 	    "vendor=0x%04hx product=0x%04hx version=0x%04hx%s%s",
515 	    HID_GET_USAGE_PAGE(tlc->usage), HID_GET_USAGE(tlc->usage),
516 	    devinfo->idBus, devinfo->idVendor, devinfo->idProduct,
517 	    devinfo->idVersion, devinfo->idPnP[0] == '\0' ? "" : " _HID=",
518 	    devinfo->idPnP[0] == '\0' ? "" : devinfo->idPnP);
519 	return (0);
520 }
521 
522 void
523 hidbus_set_desc(device_t child, const char *suffix)
524 {
525 	device_t bus = device_get_parent(child);
526 	struct hidbus_softc *sc = device_get_softc(bus);
527 	struct hid_device_info *devinfo = device_get_ivars(bus);
528 	struct hidbus_ivars *tlc = device_get_ivars(child);
529 
530 	/* Do not add NULL suffix or if device name already contains it. */
531 	if (suffix != NULL && strcasestr(devinfo->name, suffix) == NULL &&
532 	    (sc->nauto > 1 || (tlc->flags & HIDBUS_FLAG_AUTOCHILD) == 0))
533 		device_set_descf(child, "%s %s", devinfo->name, suffix);
534 	else
535 		device_set_desc(child, devinfo->name);
536 }
537 
538 device_t
539 hidbus_find_child(device_t bus, int32_t usage)
540 {
541 	device_t *children, child;
542 	int ccount, i;
543 
544 	bus_topo_assert();
545 
546 	/* Get a list of all hidbus children */
547 	if (device_get_children(bus, &children, &ccount) != 0)
548 		return (NULL);
549 
550 	/* Scan through to find required TLC */
551 	for (i = 0, child = NULL; i < ccount; i++) {
552 		if (hidbus_get_usage(children[i]) == usage) {
553 			child = children[i];
554 			break;
555 		}
556 	}
557 	free(children, M_TEMP);
558 
559 	return (child);
560 }
561 
562 void
563 hidbus_intr(void *context, void *buf, hid_size_t len)
564 {
565 	struct hidbus_softc *sc = context;
566 	struct hidbus_ivars *tlc;
567 	struct epoch_tracker et;
568 
569 	/*
570 	 * Broadcast input report to all subscribers.
571 	 * TODO: Add check for input report ID.
572 	 *
573 	 * Relock mutex on every TLC item as we can't hold any locks over whole
574 	 * TLC list here due to LOR with open()/close() handlers.
575 	 */
576 	if (!HID_IN_POLLING_MODE())
577 		epoch_enter_preempt(INPUT_EPOCH, &et);
578 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
579 		if (tlc->refcnt == 0 || tlc->intr_handler == NULL)
580 			continue;
581 		if (HID_IN_POLLING_MODE()) {
582 			if ((tlc->flags & HIDBUS_FLAG_CAN_POLL) != 0)
583 				tlc->intr_handler(tlc->intr_ctx, buf, len);
584 		} else {
585 			mtx_lock(tlc->mtx);
586 			tlc->intr_handler(tlc->intr_ctx, buf, len);
587 			mtx_unlock(tlc->mtx);
588 		}
589 	}
590 	if (!HID_IN_POLLING_MODE())
591 		epoch_exit_preempt(INPUT_EPOCH, &et);
592 }
593 
594 void
595 hidbus_set_intr(device_t child, hid_intr_t *handler, void *context)
596 {
597 	struct hidbus_ivars *tlc = device_get_ivars(child);
598 
599 	tlc->intr_handler = handler;
600 	tlc->intr_ctx = context;
601 }
602 
603 static int
604 hidbus_intr_start(device_t bus, device_t child)
605 {
606 	MPASS(bus == device_get_parent(child));
607 	struct hidbus_softc *sc = device_get_softc(bus);
608 	struct hidbus_ivars *ivar = device_get_ivars(child);
609 	struct hidbus_ivars *tlc;
610 	bool refcnted = false;
611 	int error;
612 
613 	if (sx_xlock_sig(&sc->sx) != 0)
614 		return (EINTR);
615 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
616 		refcnted |= (tlc->refcnt != 0);
617 		if (tlc == ivar) {
618 			mtx_lock(tlc->mtx);
619 			++tlc->refcnt;
620 			mtx_unlock(tlc->mtx);
621 		}
622 	}
623 	error = refcnted ? 0 : hid_intr_start(bus);
624 	sx_unlock(&sc->sx);
625 
626 	return (error);
627 }
628 
629 static int
630 hidbus_intr_stop(device_t bus, device_t child)
631 {
632 	MPASS(bus == device_get_parent(child));
633 	struct hidbus_softc *sc = device_get_softc(bus);
634 	struct hidbus_ivars *ivar = device_get_ivars(child);
635 	struct hidbus_ivars *tlc;
636 	bool refcnted = false;
637 	int error;
638 
639 	if (sx_xlock_sig(&sc->sx) != 0)
640 		return (EINTR);
641 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
642 		if (tlc == ivar) {
643 			mtx_lock(tlc->mtx);
644 			MPASS(tlc->refcnt != 0);
645 			--tlc->refcnt;
646 			mtx_unlock(tlc->mtx);
647 		}
648 		refcnted |= (tlc->refcnt != 0);
649 	}
650 	error = refcnted ? 0 : hid_intr_stop(bus);
651 	sx_unlock(&sc->sx);
652 
653 	return (error);
654 }
655 
656 static void
657 hidbus_intr_poll(device_t bus, device_t child __unused)
658 {
659 	hid_intr_poll(bus);
660 }
661 
662 struct hid_rdesc_info *
663 hidbus_get_rdesc_info(device_t child)
664 {
665 	device_t bus = device_get_parent(child);
666 	struct hidbus_softc *sc = device_get_softc(bus);
667 
668 	return (&sc->rdesc);
669 }
670 
671 /*
672  * HID interface.
673  *
674  * Hidbus as well as any hidbus child can be passed as first arg.
675  */
676 
677 /* Read cached report descriptor */
678 int
679 hid_get_report_descr(device_t dev, void **data, hid_size_t *len)
680 {
681 	device_t bus;
682 	struct hidbus_softc *sc;
683 
684 	bus = device_get_devclass(dev) == devclass_find("hidbus") ?
685 	    dev : device_get_parent(dev);
686 	sc = device_get_softc(bus);
687 
688 	/*
689 	 * Do not send request to a transport backend.
690 	 * Use cached report descriptor instead of it.
691 	 */
692 	if (sc->rdesc.data == NULL || sc->rdesc.len == 0)
693 		return (ENXIO);
694 
695 	if (data != NULL)
696 		*data = sc->rdesc.data;
697 	if (len != NULL)
698 		*len = sc->rdesc.len;
699 
700 	return (0);
701 }
702 
703 /*
704  * Replace cached report descriptor with top level driver provided one.
705  *
706  * It deletes all hidbus children except caller and enumerates them again after
707  * new descriptor has been registered. Currently it can not be called from
708  * autoenumerated (by report's TLC) child device context as it results in child
709  * duplication. To overcome this limitation hid_set_report_descr() should be
710  * called from device_identify driver's handler with hidbus itself passed as
711  * 'device_t dev' parameter.
712  */
713 int
714 hid_set_report_descr(device_t dev, const void *data, hid_size_t len)
715 {
716 	struct hid_rdesc_info rdesc;
717 	device_t bus;
718 	struct hidbus_softc *sc;
719 	bool is_bus;
720 	int error;
721 
722 	bus_topo_assert();
723 
724 	is_bus = device_get_devclass(dev) == devclass_find("hidbus");
725 	bus = is_bus ? dev : device_get_parent(dev);
726 	sc = device_get_softc(bus);
727 
728 	/*
729 	 * Do not overload already overloaded report descriptor in
730 	 * device_identify handler. It causes infinite recursion loop.
731 	 */
732 	if (is_bus && sc->overloaded)
733 		return(0);
734 
735 	DPRINTFN(5, "len=%d\n", len);
736 	DPRINTFN(5, "data = %*D\n", len, data, " ");
737 
738 	error = hidbus_fill_rdesc_info(&rdesc, data, len);
739 	if (error != 0)
740 		return (error);
741 
742 	error = hidbus_detach_children(dev);
743 	if (error != 0)
744 		return(error);
745 
746 	/* Make private copy to handle a case of dynamicaly allocated data. */
747 	rdesc.data = malloc(len, M_DEVBUF, M_ZERO | M_WAITOK);
748 	bcopy(data, rdesc.data, len);
749 	sc->overloaded = true;
750 	free(sc->rdesc.data, M_DEVBUF);
751 	bcopy(&rdesc, &sc->rdesc, sizeof(struct hid_rdesc_info));
752 
753 	error = hidbus_attach_children(bus);
754 
755 	return (error);
756 }
757 
758 static int
759 hidbus_get_rdesc(device_t dev, device_t child __unused, void *data,
760     hid_size_t len)
761 {
762 	return (hid_get_rdesc(dev, data, len));
763 }
764 
765 static int
766 hidbus_read(device_t dev, device_t child __unused, void *data,
767     hid_size_t maxlen, hid_size_t *actlen)
768 {
769 	return (hid_read(dev, data, maxlen, actlen));
770 }
771 
772 static int
773 hidbus_write(device_t dev, device_t child __unused, const void *data,
774     hid_size_t len)
775 {
776 	struct hidbus_softc *sc;
777 	uint8_t id;
778 
779 	sc = device_get_softc(dev);
780 	/*
781 	 * Output interrupt endpoint is often optional. If HID device
782 	 * does not provide it, send reports via control pipe.
783 	 */
784 	if (sc->nowrite) {
785 		/* try to extract the ID byte */
786 		id = (sc->rdesc.oid & (len > 0)) ? *(const uint8_t*)data : 0;
787 		return (hid_set_report(dev, data, len, HID_OUTPUT_REPORT, id));
788 	}
789 
790 	return (hid_write(dev, data, len));
791 }
792 
793 static int
794 hidbus_get_report(device_t dev, device_t child __unused, void *data,
795     hid_size_t maxlen, hid_size_t *actlen, uint8_t type, uint8_t id)
796 {
797 	return (hid_get_report(dev, data, maxlen, actlen, type, id));
798 }
799 
800 static int
801 hidbus_set_report(device_t dev, device_t child __unused, const void *data,
802     hid_size_t len, uint8_t type, uint8_t id)
803 {
804 	return (hid_set_report(dev, data, len, type, id));
805 }
806 
807 static int
808 hidbus_set_idle(device_t dev, device_t child __unused, uint16_t duration,
809     uint8_t id)
810 {
811 	return (hid_set_idle(dev, duration, id));
812 }
813 
814 static int
815 hidbus_set_protocol(device_t dev, device_t child __unused, uint16_t protocol)
816 {
817 	return (hid_set_protocol(dev, protocol));
818 }
819 
820 static int
821 hidbus_ioctl(device_t dev, device_t child __unused, unsigned long cmd,
822     uintptr_t data)
823 {
824 	return (hid_ioctl(dev, cmd, data));
825 }
826 
827 /*------------------------------------------------------------------------*
828  *	hidbus_lookup_id
829  *
830  * This functions takes an array of "struct hid_device_id" and tries
831  * to match the entries with the information in "struct hid_device_info".
832  *
833  * Return values:
834  * NULL: No match found.
835  * Else: Pointer to matching entry.
836  *------------------------------------------------------------------------*/
837 const struct hid_device_id *
838 hidbus_lookup_id(device_t dev, const struct hid_device_id *id, int nitems_id)
839 {
840 	const struct hid_device_id *id_end;
841 	const struct hid_device_info *info;
842 	int32_t usage;
843 	bool is_child;
844 
845 	if (id == NULL) {
846 		goto done;
847 	}
848 
849 	id_end = id + nitems_id;
850 	info = hid_get_device_info(dev);
851 	is_child = device_get_devclass(dev) != devclass_find("hidbus");
852 	if (is_child)
853 		usage = hidbus_get_usage(dev);
854 
855 	/*
856 	 * Keep on matching array entries until we find a match or
857 	 * until we reach the end of the matching array:
858 	 */
859 	for (; id != id_end; id++) {
860 
861 		if (is_child && (id->match_flag_page) &&
862 		    (id->page != HID_GET_USAGE_PAGE(usage))) {
863 			continue;
864 		}
865 		if (is_child && (id->match_flag_usage) &&
866 		    (id->usage != HID_GET_USAGE(usage))) {
867 			continue;
868 		}
869 		if ((id->match_flag_bus) &&
870 		    (id->idBus != info->idBus)) {
871 			continue;
872 		}
873 		if ((id->match_flag_vendor) &&
874 		    (id->idVendor != info->idVendor)) {
875 			continue;
876 		}
877 		if ((id->match_flag_product) &&
878 		    (id->idProduct != info->idProduct)) {
879 			continue;
880 		}
881 		if ((id->match_flag_ver_lo) &&
882 		    (id->idVersion_lo > info->idVersion)) {
883 			continue;
884 		}
885 		if ((id->match_flag_ver_hi) &&
886 		    (id->idVersion_hi < info->idVersion)) {
887 			continue;
888 		}
889 		if (id->match_flag_pnp &&
890 		    strncmp(id->idPnP, info->idPnP, HID_PNP_ID_SIZE) != 0) {
891 			continue;
892 		}
893 		/* We found a match! */
894 		return (id);
895 	}
896 
897 done:
898 	return (NULL);
899 }
900 
901 /*------------------------------------------------------------------------*
902  *	hidbus_lookup_driver_info - factored out code
903  *
904  * Return values:
905  *    0: Success
906  * Else: Failure
907  *------------------------------------------------------------------------*/
908 int
909 hidbus_lookup_driver_info(device_t child, const struct hid_device_id *id,
910     int nitems_id)
911 {
912 
913 	id = hidbus_lookup_id(child, id, nitems_id);
914 	if (id) {
915 		/* copy driver info */
916 		hidbus_set_driver_info(child, id->driver_info);
917 		return (0);
918 	}
919 	return (ENXIO);
920 }
921 
922 const struct hid_device_info *
923 hid_get_device_info(device_t dev)
924 {
925 	device_t bus;
926 
927 	bus = device_get_devclass(dev) == devclass_find("hidbus") ?
928 	    dev : device_get_parent(dev);
929 
930 	return (device_get_ivars(bus));
931 }
932 
933 static device_method_t hidbus_methods[] = {
934 	/* device interface */
935 	DEVMETHOD(device_probe,		hidbus_probe),
936 	DEVMETHOD(device_attach,	hidbus_attach),
937 	DEVMETHOD(device_detach,	hidbus_detach),
938 	DEVMETHOD(device_suspend,	bus_generic_suspend),
939 	DEVMETHOD(device_resume,	bus_generic_resume),
940 
941 	/* bus interface */
942 	DEVMETHOD(bus_add_child,	hidbus_add_child),
943 	DEVMETHOD(bus_child_detached,	hidbus_child_detached),
944 	DEVMETHOD(bus_child_deleted,	hidbus_child_deleted),
945 	DEVMETHOD(bus_read_ivar,	hidbus_read_ivar),
946 	DEVMETHOD(bus_write_ivar,	hidbus_write_ivar),
947 	DEVMETHOD(bus_child_pnpinfo,	hidbus_child_pnpinfo),
948 	DEVMETHOD(bus_child_location,	hidbus_child_location),
949 
950 	/* hid interface */
951 	DEVMETHOD(hid_intr_start,	hidbus_intr_start),
952 	DEVMETHOD(hid_intr_stop,	hidbus_intr_stop),
953 	DEVMETHOD(hid_intr_poll,	hidbus_intr_poll),
954 	DEVMETHOD(hid_get_rdesc,	hidbus_get_rdesc),
955 	DEVMETHOD(hid_read,		hidbus_read),
956 	DEVMETHOD(hid_write,		hidbus_write),
957 	DEVMETHOD(hid_get_report,	hidbus_get_report),
958 	DEVMETHOD(hid_set_report,	hidbus_set_report),
959 	DEVMETHOD(hid_set_idle,		hidbus_set_idle),
960 	DEVMETHOD(hid_set_protocol,	hidbus_set_protocol),
961 	DEVMETHOD(hid_ioctl,		hidbus_ioctl),
962 
963 	DEVMETHOD_END
964 };
965 
966 driver_t hidbus_driver = {
967 	"hidbus",
968 	hidbus_methods,
969 	sizeof(struct hidbus_softc),
970 };
971 
972 MODULE_DEPEND(hidbus, hid, 1, 1, 1);
973 MODULE_VERSION(hidbus, 1);
974 DRIVER_MODULE(hidbus, atopcase, hidbus_driver, 0, 0);
975 DRIVER_MODULE(hidbus, hvhid, hidbus_driver, 0, 0);
976 DRIVER_MODULE(hidbus, iichid, hidbus_driver, 0, 0);
977 DRIVER_MODULE(hidbus, usbhid, hidbus_driver, 0, 0);
978