xref: /freebsd/sys/dev/hid/hmt.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2014-2020 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/cdefs.h>
29 /*
30  * MS Windows 7/8/10 compatible HID Multi-touch Device driver.
31  * https://msdn.microsoft.com/en-us/library/windows/hardware/jj151569(v=vs.85).aspx
32  * http://download.microsoft.com/download/7/d/d/7dd44bb7-2a7a-4505-ac1c-7227d3d96d5b/hid-over-i2c-protocol-spec-v1-0.docx
33  * https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt
34  */
35 
36 #include "opt_hid.h"
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/malloc.h>
43 #include <sys/module.h>
44 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
46 #include <sys/systm.h>
47 
48 #include <dev/evdev/evdev.h>
49 #include <dev/evdev/input.h>
50 
51 #define	HID_DEBUG_VAR	hmt_debug
52 #include <dev/hid/hid.h>
53 #include <dev/hid/hidbus.h>
54 #include <dev/hid/hidquirk.h>
55 
56 #include <dev/hid/hconf.h>
57 
58 static SYSCTL_NODE(_hw_hid, OID_AUTO, hmt, CTLFLAG_RW, 0,
59     "MSWindows 7/8/10 compatible HID Multi-touch Device");
60 #ifdef HID_DEBUG
61 static int hmt_debug = 0;
62 SYSCTL_INT(_hw_hid_hmt, OID_AUTO, debug, CTLFLAG_RWTUN,
63     &hmt_debug, 1, "Debug level");
64 #endif
65 static bool hmt_timestamps = 0;
66 SYSCTL_BOOL(_hw_hid_hmt, OID_AUTO, timestamps, CTLFLAG_RDTUN,
67     &hmt_timestamps, 1, "Enable hardware timestamp reporting");
68 
69 #define	HMT_BTN_MAX	8	/* Number of buttons supported */
70 
71 enum hmt_type {
72 	HMT_TYPE_UNKNOWN = 0,	/* HID report descriptor is not probed */
73 	HMT_TYPE_UNSUPPORTED,	/* Repdescr does not belong to MT device */
74 	HMT_TYPE_TOUCHPAD,
75 	HMT_TYPE_TOUCHSCREEN,
76 };
77 
78 enum {
79 	HMT_TIP_SWITCH =	ABS_MT_INDEX(ABS_MT_TOOL_TYPE),
80 	HMT_WIDTH =		ABS_MT_INDEX(ABS_MT_TOUCH_MAJOR),
81 	HMT_HEIGHT =		ABS_MT_INDEX(ABS_MT_TOUCH_MINOR),
82 	HMT_ORIENTATION = 	ABS_MT_INDEX(ABS_MT_ORIENTATION),
83 	HMT_X =			ABS_MT_INDEX(ABS_MT_POSITION_X),
84 	HMT_Y =			ABS_MT_INDEX(ABS_MT_POSITION_Y),
85 	HMT_CONTACTID = 	ABS_MT_INDEX(ABS_MT_TRACKING_ID),
86 	HMT_PRESSURE =		ABS_MT_INDEX(ABS_MT_PRESSURE),
87 	HMT_IN_RANGE = 		ABS_MT_INDEX(ABS_MT_DISTANCE),
88 	HMT_CONFIDENCE = 	ABS_MT_INDEX(ABS_MT_BLOB_ID),
89 	HMT_TOOL_X =		ABS_MT_INDEX(ABS_MT_TOOL_X),
90 	HMT_TOOL_Y = 		ABS_MT_INDEX(ABS_MT_TOOL_Y),
91 };
92 
93 #define	HMT_N_USAGES	MT_CNT
94 #define	HMT_NO_USAGE	-1
95 
96 struct hmt_hid_map_item {
97 	char		name[5];
98 	int32_t 	usage;		/* HID usage */
99 	bool		reported;	/* Item value is passed to evdev */
100 	bool		required;	/* Required for MT Digitizers */
101 };
102 
103 static const struct hmt_hid_map_item hmt_hid_map[HMT_N_USAGES] = {
104 	[HMT_TIP_SWITCH] = {
105 		.name = "TIP",
106 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_TIP_SWITCH),
107 		.reported = false,
108 		.required = true,
109 	},
110 	[HMT_WIDTH] = {
111 		.name = "WDTH",
112 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_WIDTH),
113 		.reported = true,
114 		.required = false,
115 	},
116 	[HMT_HEIGHT] = {
117 		.name = "HGHT",
118 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_HEIGHT),
119 		.reported = true,
120 		.required = false,
121 	},
122 	[HMT_ORIENTATION] = {
123 		.name = "ORIE",
124 		.usage = HMT_NO_USAGE,
125 		.reported = true,
126 		.required = false,
127 	},
128 	[HMT_X] = {
129 		.name = "X",
130 		.usage = HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_X),
131 		.reported = true,
132 		.required = true,
133 	},
134 	[HMT_Y] = {
135 		.name = "Y",
136 		.usage = HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y),
137 		.reported = true,
138 		.required = true,
139 	},
140 	[HMT_CONTACTID] = {
141 		.name = "C_ID",
142 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTID),
143 		.reported = true,
144 		.required = true,
145 	},
146 	[HMT_PRESSURE] = {
147 		.name = "PRES",
148 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_TIP_PRESSURE),
149 		.reported = true,
150 		.required = false,
151 	},
152 	[HMT_IN_RANGE] = {
153 		.name = "RANG",
154 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_IN_RANGE),
155 		.reported = true,
156 		.required = false,
157 	},
158 	[HMT_CONFIDENCE] = {
159 		.name = "CONF",
160 		.usage = HID_USAGE2(HUP_DIGITIZERS, HUD_CONFIDENCE),
161 		.reported = false,
162 		.required = false,
163 	},
164 	[HMT_TOOL_X] = { /* Shares HID usage with POS_X */
165 		.name = "TL_X",
166 		.usage = HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_X),
167 		.reported = true,
168 		.required = false,
169 	},
170 	[HMT_TOOL_Y] = { /* Shares HID usage with POS_Y */
171 		.name = "TL_Y",
172 		.usage = HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y),
173 		.reported = true,
174 		.required = false,
175 	},
176 };
177 
178 struct hmt_softc {
179 	device_t		dev;
180 	enum hmt_type		type;
181 
182 	int32_t			cont_count_max;
183 	struct hid_absinfo	ai[HMT_N_USAGES];
184 	struct hid_location	locs[MAX_MT_SLOTS][HMT_N_USAGES];
185 	struct hid_location	cont_count_loc;
186 	struct hid_location	btn_loc[HMT_BTN_MAX];
187 	struct hid_location	int_btn_loc;
188 	struct hid_location	scan_time_loc;
189 	int32_t			scan_time_max;
190 	int32_t			scan_time;
191 	int32_t			timestamp;
192 	bool			touch;
193 	bool			prev_touch;
194 
195 	struct evdev_dev	*evdev;
196 
197 	union evdev_mt_slot	slot_data;
198 	uint8_t			caps[howmany(HMT_N_USAGES, 8)];
199 	uint8_t			buttons[howmany(HMT_BTN_MAX, 8)];
200 	uint32_t		nconts_per_report;
201 	uint32_t		nconts_todo;
202 	uint8_t			report_id;
203 	uint32_t		max_button;
204 	bool			has_int_button;
205 	bool			has_cont_count;
206 	bool			has_scan_time;
207 	bool			is_clickpad;
208 	bool			do_timestamps;
209 #ifdef IICHID_SAMPLING
210 	bool			iichid_sampling;
211 #endif
212 
213 	struct hid_location	cont_max_loc;
214 	uint32_t		cont_max_rlen;
215 	uint8_t			cont_max_rid;
216 	struct hid_location	btn_type_loc;
217 	uint32_t		btn_type_rlen;
218 	uint8_t			btn_type_rid;
219 	uint32_t		thqa_cert_rlen;
220 	uint8_t			thqa_cert_rid;
221 };
222 
223 #define	HMT_FOREACH_USAGE(caps, usage)			\
224 	for ((usage) = 0; (usage) < HMT_N_USAGES; ++(usage))	\
225 		if (isset((caps), (usage)))
226 
227 static enum hmt_type hmt_hid_parse(struct hmt_softc *, const void *,
228     hid_size_t, uint32_t, uint8_t);
229 static int hmt_set_input_mode(struct hmt_softc *, enum hconf_input_mode);
230 
231 static hid_intr_t	hmt_intr;
232 
233 static device_probe_t	hmt_probe;
234 static device_attach_t	hmt_attach;
235 static device_detach_t	hmt_detach;
236 
237 static evdev_open_t	hmt_ev_open;
238 static evdev_close_t	hmt_ev_close;
239 
240 static const struct evdev_methods hmt_evdev_methods = {
241 	.ev_open = &hmt_ev_open,
242 	.ev_close = &hmt_ev_close,
243 };
244 
245 static const struct hid_device_id hmt_devs[] = {
246 	{ HID_TLC(HUP_DIGITIZERS, HUD_TOUCHSCREEN) },
247 	{ HID_TLC(HUP_DIGITIZERS, HUD_TOUCHPAD) },
248 };
249 
250 static int
251 hmt_ev_close(struct evdev_dev *evdev)
252 {
253 	return (hid_intr_stop(evdev_get_softc(evdev)));
254 }
255 
256 static int
257 hmt_ev_open(struct evdev_dev *evdev)
258 {
259 	return (hid_intr_start(evdev_get_softc(evdev)));
260 }
261 
262 static int
263 hmt_probe(device_t dev)
264 {
265 	struct hmt_softc *sc = device_get_softc(dev);
266 	void *d_ptr;
267 	hid_size_t d_len;
268 	int err;
269 
270 	err = HIDBUS_LOOKUP_DRIVER_INFO(dev, hmt_devs);
271 	if (err != 0)
272 		return (err);
273 
274 	err = hid_get_report_descr(dev, &d_ptr, &d_len);
275 	if (err != 0) {
276 		device_printf(dev, "could not retrieve report descriptor from "
277 		     "device: %d\n", err);
278 		return (ENXIO);
279 	}
280 
281 	/* Check if report descriptor belongs to a HID multitouch device */
282 	if (sc->type == HMT_TYPE_UNKNOWN)
283 		sc->type = hmt_hid_parse(sc, d_ptr, d_len,
284 		    hidbus_get_usage(dev), hidbus_get_index(dev));
285 	if (sc->type == HMT_TYPE_UNSUPPORTED)
286 		return (ENXIO);
287 
288 	hidbus_set_desc(dev,
289 	    sc->type == HMT_TYPE_TOUCHPAD ? "TouchPad" : "TouchScreen");
290 
291 	return (BUS_PROBE_DEFAULT);
292 }
293 
294 static int
295 hmt_attach(device_t dev)
296 {
297 	struct hmt_softc *sc = device_get_softc(dev);
298 	const struct hid_device_info *hw = hid_get_device_info(dev);
299 	void *d_ptr;
300 	uint8_t *fbuf = NULL;
301 	hid_size_t d_len, fsize, rsize;
302 	uint32_t cont_count_max;
303 	int nbuttons, btn;
304 	size_t i;
305 	int err;
306 
307 	err = hid_get_report_descr(dev, &d_ptr, &d_len);
308 	if (err != 0) {
309 		device_printf(dev, "could not retrieve report descriptor from "
310 		    "device: %d\n", err);
311 		return (ENXIO);
312 	}
313 
314 	sc->dev = dev;
315 
316 	fsize = hid_report_size_max(d_ptr, d_len, hid_feature, NULL);
317 	if (fsize != 0)
318 		fbuf = malloc(fsize, M_TEMP, M_WAITOK | M_ZERO);
319 
320 	/* Fetch and parse "Contact count maximum" feature report */
321 	if (sc->cont_max_rlen > 1) {
322 		err = hid_get_report(dev, fbuf, sc->cont_max_rlen, &rsize,
323 		    HID_FEATURE_REPORT, sc->cont_max_rid);
324 		if (err == 0 && (rsize - 1) * 8 >=
325 		    sc->cont_max_loc.pos + sc->cont_max_loc.size) {
326 			cont_count_max = hid_get_udata(fbuf + 1,
327 			    sc->cont_max_rlen - 1, &sc->cont_max_loc);
328 			/*
329 			 * Feature report is a primary source of
330 			 * 'Contact Count Maximum'
331 			 */
332 			if (cont_count_max > 0)
333 				sc->cont_count_max = cont_count_max;
334 		} else
335 			DPRINTF("hid_get_report error=%d\n", err);
336 	}
337 	if (sc->cont_count_max == 0)
338 		sc->cont_count_max = sc->type == HMT_TYPE_TOUCHSCREEN ? 10 : 5;
339 
340 	/* Fetch and parse "Button type" feature report */
341 	if (sc->btn_type_rlen > 1 && sc->btn_type_rid != sc->cont_max_rid) {
342 		bzero(fbuf, fsize);
343 		err = hid_get_report(dev, fbuf, sc->btn_type_rlen, &rsize,
344 		    HID_FEATURE_REPORT, sc->btn_type_rid);
345 		if (err != 0)
346 			DPRINTF("hid_get_report error=%d\n", err);
347 	}
348 	if (sc->btn_type_rlen > 1 && err == 0 && (rsize - 1) * 8 >=
349 	    sc->btn_type_loc.pos + sc->btn_type_loc.size)
350 		sc->is_clickpad = hid_get_udata(fbuf + 1, sc->btn_type_rlen - 1,
351 		    &sc->btn_type_loc) == 0;
352 	else
353 		sc->is_clickpad = sc->max_button == 0 && sc->has_int_button;
354 
355 	/* Fetch THQA certificate to enable some devices like WaveShare */
356 	if (sc->thqa_cert_rlen > 1 && sc->thqa_cert_rid != sc->cont_max_rid)
357 		(void)hid_get_report(dev, fbuf, sc->thqa_cert_rlen, NULL,
358 		    HID_FEATURE_REPORT, sc->thqa_cert_rid);
359 
360 	free(fbuf, M_TEMP);
361 
362 	/* Switch touchpad in to absolute multitouch mode */
363 	if (sc->type == HMT_TYPE_TOUCHPAD) {
364 		err = hmt_set_input_mode(sc, HCONF_INPUT_MODE_MT_TOUCHPAD);
365 		if (err != 0)
366 			DPRINTF("Failed to set input mode: %d\n", err);
367 	}
368 
369 	/* Cap contact count maximum to MAX_MT_SLOTS */
370 	if (sc->cont_count_max > MAX_MT_SLOTS) {
371 		DPRINTF("Hardware reported %d contacts while only %d is "
372 		    "supported\n", sc->cont_count_max, MAX_MT_SLOTS);
373 		sc->cont_count_max = MAX_MT_SLOTS;
374 	}
375 
376 	if (sc->has_scan_time &&
377 	    (hid_test_quirk(hw, HQ_MT_TIMESTAMP) || hmt_timestamps))
378 		sc->do_timestamps = true;
379 #ifdef IICHID_SAMPLING
380 	if (hid_test_quirk(hw, HQ_IICHID_SAMPLING))
381 		sc->iichid_sampling = true;
382 #endif
383 
384 	hidbus_set_intr(dev, hmt_intr, sc);
385 
386 	sc->evdev = evdev_alloc();
387 	evdev_set_name(sc->evdev, device_get_desc(dev));
388 	evdev_set_phys(sc->evdev, device_get_nameunit(dev));
389 	evdev_set_id(sc->evdev, hw->idBus, hw->idVendor, hw->idProduct,
390 	    hw->idVersion);
391 	evdev_set_serial(sc->evdev, hw->serial);
392 	evdev_set_methods(sc->evdev, dev, &hmt_evdev_methods);
393 	evdev_set_flag(sc->evdev, EVDEV_FLAG_MT_STCOMPAT);
394 	evdev_set_flag(sc->evdev, EVDEV_FLAG_EXT_EPOCH); /* hidbus child */
395 	switch (sc->type) {
396 	case HMT_TYPE_TOUCHSCREEN:
397 		evdev_support_prop(sc->evdev, INPUT_PROP_DIRECT);
398 		break;
399 	case HMT_TYPE_TOUCHPAD:
400 		evdev_support_prop(sc->evdev, INPUT_PROP_POINTER);
401 		if (sc->is_clickpad)
402 			evdev_support_prop(sc->evdev, INPUT_PROP_BUTTONPAD);
403 		break;
404 	default:
405 		KASSERT(0, ("hmt_attach: unsupported touch device type"));
406 	}
407 	evdev_support_event(sc->evdev, EV_SYN);
408 	evdev_support_event(sc->evdev, EV_ABS);
409 	if (sc->do_timestamps) {
410 		evdev_support_event(sc->evdev, EV_MSC);
411 		evdev_support_msc(sc->evdev, MSC_TIMESTAMP);
412 	}
413 #ifdef IICHID_SAMPLING
414 	if (sc->iichid_sampling)
415 		evdev_set_flag(sc->evdev, EVDEV_FLAG_MT_AUTOREL);
416 #endif
417 	nbuttons = 0;
418 	if (sc->max_button != 0 || sc->has_int_button) {
419 		evdev_support_event(sc->evdev, EV_KEY);
420 		if (sc->has_int_button)
421 			evdev_support_key(sc->evdev, BTN_LEFT);
422 		for (btn = 0; btn < sc->max_button; ++btn) {
423 			if (isset(sc->buttons, btn)) {
424 				evdev_support_key(sc->evdev, BTN_MOUSE + btn);
425 				nbuttons++;
426 			}
427 		}
428 	}
429 	evdev_support_abs(sc->evdev,
430 	    ABS_MT_SLOT, 0, sc->cont_count_max - 1, 0, 0, 0);
431 	HMT_FOREACH_USAGE(sc->caps, i) {
432 		if (hmt_hid_map[i].reported)
433 			evdev_support_abs(sc->evdev, ABS_MT_FIRST + i,
434 			    sc->ai[i].min, sc->ai[i].max, 0, 0, sc->ai[i].res);
435 	}
436 
437 	err = evdev_register(sc->evdev);
438 	if (err) {
439 		hmt_detach(dev);
440 		return (ENXIO);
441 	}
442 
443 	/* Announce information about the touch device */
444 	device_printf(sc->dev, "%s %s with %d external button%s%s\n",
445 	    sc->cont_count_max > 1 ? "Multitouch" : "Singletouch",
446 	    sc->type == HMT_TYPE_TOUCHSCREEN ? "touchscreen" : "touchpad",
447 	    nbuttons, nbuttons != 1 ? "s" : "",
448 	    sc->is_clickpad ? ", click-pad" : "");
449 	device_printf(sc->dev,
450 	    "%d contact%s with [%s%s%s%s%s] properties. Report range [%d:%d] - [%d:%d]\n",
451 	    (int)sc->cont_count_max, sc->cont_count_max != 1 ? "s" : "",
452 	    isset(sc->caps, HMT_IN_RANGE) ? "R" : "",
453 	    isset(sc->caps, HMT_CONFIDENCE) ? "C" : "",
454 	    isset(sc->caps, HMT_WIDTH) ? "W" : "",
455 	    isset(sc->caps, HMT_HEIGHT) ? "H" : "",
456 	    isset(sc->caps, HMT_PRESSURE) ? "P" : "",
457 	    (int)sc->ai[HMT_X].min, (int)sc->ai[HMT_Y].min,
458 	    (int)sc->ai[HMT_X].max, (int)sc->ai[HMT_Y].max);
459 
460 	return (0);
461 }
462 
463 static int
464 hmt_detach(device_t dev)
465 {
466 	struct hmt_softc *sc = device_get_softc(dev);
467 
468 	evdev_free(sc->evdev);
469 
470 	return (0);
471 }
472 
473 static void
474 hmt_intr(void *context, void *buf, hid_size_t len)
475 {
476 	struct hmt_softc *sc = context;
477 	size_t usage;
478 	union evdev_mt_slot *slot_data;
479 	uint32_t cont, btn;
480 	uint32_t cont_count;
481 	uint32_t width;
482 	uint32_t height;
483 	uint32_t int_btn = 0;
484 	uint32_t left_btn = 0;
485 	int slot;
486 	uint32_t scan_time;
487 	int32_t delta;
488 	uint8_t id;
489 
490 #ifdef IICHID_SAMPLING
491 	/*
492 	 * Special packet of zero length is generated by iichid driver running
493 	 * in polling mode at the start of inactivity period to workaround
494 	 * "stuck touch" problem caused by miss of finger release events.
495 	 * This snippet is to be removed after GPIO interrupt support is added.
496 	 */
497 	if (sc->iichid_sampling && len == 0) {
498 		sc->prev_touch = false;
499 		sc->timestamp = 0;
500 		/* EVDEV_FLAG_MT_AUTOREL releases all touches for us */
501 		evdev_sync(sc->evdev);
502 		return;
503 	}
504 #endif
505 
506 	/* Ignore irrelevant reports */
507 	id = sc->report_id != 0 ? *(uint8_t *)buf : 0;
508 	if (sc->report_id != id) {
509 		DPRINTF("Skip report with unexpected ID: %hhu\n", id);
510 		return;
511 	}
512 
513 	/* Strip leading "report ID" byte */
514 	if (sc->report_id != 0) {
515 		len--;
516 		buf = (uint8_t *)buf + 1;
517 	}
518 
519 	/*
520 	 * "In Serial mode, each packet contains information that describes a
521 	 * single physical contact point. Multiple contacts are streamed
522 	 * serially. In this mode, devices report all contact information in a
523 	 * series of packets. The device sends a separate packet for each
524 	 * concurrent contact."
525 	 *
526 	 * "In Parallel mode, devices report all contact information in a
527 	 * single packet. Each physical contact is represented by a logical
528 	 * collection that is embedded in the top-level collection."
529 	 *
530 	 * Since additional contacts that were not present will still be in the
531 	 * report with contactid=0 but contactids are zero-based, find
532 	 * contactcount first.
533 	 */
534 	if (sc->has_cont_count)
535 		cont_count = hid_get_udata(buf, len, &sc->cont_count_loc);
536 	else
537 		cont_count = 1;
538 	/*
539 	 * "In Hybrid mode, the number of contacts that can be reported in one
540 	 * report is less than the maximum number of contacts that the device
541 	 * supports. For example, a device that supports a maximum of
542 	 * 4 concurrent physical contacts, can set up its top-level collection
543 	 * to deliver a maximum of two contacts in one report. If four contact
544 	 * points are present, the device can break these up into two serial
545 	 * reports that deliver two contacts each.
546 	 *
547 	 * "When a device delivers data in this manner, the Contact Count usage
548 	 * value in the first report should reflect the total number of
549 	 * contacts that are being delivered in the hybrid reports. The other
550 	 * serial reports should have a contact count of zero (0)."
551 	 */
552 	if (cont_count != 0)
553 		sc->nconts_todo = cont_count;
554 
555 #ifdef HID_DEBUG
556 	DPRINTFN(6, "cont_count:%2u", (unsigned)cont_count);
557 	if (hmt_debug >= 6) {
558 		HMT_FOREACH_USAGE(sc->caps, usage) {
559 			if (hmt_hid_map[usage].usage != HMT_NO_USAGE)
560 				printf(" %-4s", hmt_hid_map[usage].name);
561 		}
562 		printf("\n");
563 	}
564 #endif
565 
566 	/* Find the number of contacts reported in current report */
567 	cont_count = MIN(sc->nconts_todo, sc->nconts_per_report);
568 
569 	/* Use protocol Type B for reporting events */
570 	for (cont = 0; cont < cont_count; cont++) {
571 		slot_data = &sc->slot_data;
572 		bzero(slot_data, sizeof(sc->slot_data));
573 		HMT_FOREACH_USAGE(sc->caps, usage) {
574 			if (sc->locs[cont][usage].size > 0)
575 				slot_data->val[usage] = hid_get_udata(
576 				    buf, len, &sc->locs[cont][usage]);
577 		}
578 
579 		slot = evdev_mt_id_to_slot(sc->evdev, slot_data->id);
580 
581 #ifdef HID_DEBUG
582 		DPRINTFN(6, "cont%01x: data = ", cont);
583 		if (hmt_debug >= 6) {
584 			HMT_FOREACH_USAGE(sc->caps, usage) {
585 				if (hmt_hid_map[usage].usage != HMT_NO_USAGE)
586 					printf("%04x ", slot_data->val[usage]);
587 			}
588 			printf("slot = %d\n", slot);
589 		}
590 #endif
591 
592 		if (slot == -1) {
593 			DPRINTF("Slot overflow for contact_id %u\n",
594 			    (unsigned)slot_data->id);
595 			continue;
596 		}
597 
598 		if (slot_data->val[HMT_TIP_SWITCH] != 0 &&
599 		    !(isset(sc->caps, HMT_CONFIDENCE) &&
600 		      slot_data->val[HMT_CONFIDENCE] == 0)) {
601 			/* This finger is in proximity of the sensor */
602 			sc->touch = true;
603 			slot_data->dist = !slot_data->val[HMT_IN_RANGE];
604 			/* Divided by two to match visual scale of touch */
605 			width = slot_data->val[HMT_WIDTH] >> 1;
606 			height = slot_data->val[HMT_HEIGHT] >> 1;
607 			slot_data->ori = width > height;
608 			slot_data->maj = MAX(width, height);
609 			slot_data->min = MIN(width, height);
610 		} else
611 			slot_data = NULL;
612 
613 		evdev_mt_push_slot(sc->evdev, slot, slot_data);
614 	}
615 
616 	sc->nconts_todo -= cont_count;
617 	if (sc->do_timestamps && sc->nconts_todo == 0) {
618 		/* HUD_SCAN_TIME is measured in 100us, convert to us. */
619 		scan_time = hid_get_udata(buf, len, &sc->scan_time_loc);
620 		if (sc->prev_touch) {
621 			delta = scan_time - sc->scan_time;
622 			if (delta < 0)
623 				delta += sc->scan_time_max;
624 		} else
625 			delta = 0;
626 		sc->scan_time = scan_time;
627 		sc->timestamp += delta * 100;
628 		evdev_push_msc(sc->evdev, MSC_TIMESTAMP, sc->timestamp);
629 		sc->prev_touch = sc->touch;
630 		sc->touch = false;
631 		if (!sc->prev_touch)
632 			sc->timestamp = 0;
633 	}
634 	if (sc->nconts_todo == 0) {
635 		/* Report both the click and external left btns as BTN_LEFT */
636 		if (sc->has_int_button)
637 			int_btn = hid_get_data(buf, len, &sc->int_btn_loc);
638 		if (isset(sc->buttons, 0))
639 			left_btn = hid_get_data(buf, len, &sc->btn_loc[0]);
640 		if (sc->has_int_button || isset(sc->buttons, 0))
641 			evdev_push_key(sc->evdev, BTN_LEFT,
642 			    (int_btn != 0) | (left_btn != 0));
643 		for (btn = 1; btn < sc->max_button; ++btn) {
644 			if (isset(sc->buttons, btn))
645 				evdev_push_key(sc->evdev, BTN_MOUSE + btn,
646 				    hid_get_data(buf,
647 						 len,
648 						 &sc->btn_loc[btn]) != 0);
649 		}
650 		evdev_sync(sc->evdev);
651 	}
652 }
653 
654 static enum hmt_type
655 hmt_hid_parse(struct hmt_softc *sc, const void *d_ptr, hid_size_t d_len,
656     uint32_t tlc_usage, uint8_t tlc_index)
657 {
658 	struct hid_absinfo ai;
659 	struct hid_item hi;
660 	struct hid_data *hd;
661 	uint32_t flags;
662 	size_t i;
663 	size_t cont = 0;
664 	enum hmt_type type;
665 	uint32_t left_btn, btn;
666 	int32_t cont_count_max = 0;
667 	uint8_t report_id = 0;
668 	bool finger_coll = false;
669 	bool cont_count_found = false;
670 	bool scan_time_found = false;
671 	bool has_int_button = false;
672 
673 #define HMT_HI_ABSOLUTE(hi)	((hi).nusages != 0 &&	\
674 	((hi).flags & (HIO_VARIABLE | HIO_RELATIVE)) == HIO_VARIABLE)
675 #define	HUMS_THQA_CERT	0xC5
676 
677 	/*
678 	 * Get left button usage taking in account MS Precision Touchpad specs.
679 	 * For Windows PTP report descriptor assigns buttons in following way:
680 	 * Button 1 - Indicates Button State for touchpad button integrated
681 	 *            with digitizer.
682 	 * Button 2 - Indicates Button State for external button for primary
683 	 *            (default left) clicking.
684 	 * Button 3 - Indicates Button State for external button for secondary
685 	 *            (default right) clicking.
686 	 * If a device only supports external buttons, it must still use
687 	 * Button 2 and Button 3 to reference the external buttons.
688 	 */
689 	switch (tlc_usage) {
690 	case HID_USAGE2(HUP_DIGITIZERS, HUD_TOUCHSCREEN):
691 		type = HMT_TYPE_TOUCHSCREEN;
692 		left_btn = 1;
693 		break;
694 	case HID_USAGE2(HUP_DIGITIZERS, HUD_TOUCHPAD):
695 		type = HMT_TYPE_TOUCHPAD;
696 		left_btn = 2;
697 		break;
698 	default:
699 		return (HMT_TYPE_UNSUPPORTED);
700 	}
701 
702 	/* Parse features for mandatory maximum contact count usage */
703 	if (!hidbus_locate(d_ptr, d_len,
704 	    HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACT_MAX), hid_feature,
705 	    tlc_index, 0, &sc->cont_max_loc, &flags, &sc->cont_max_rid, &ai) ||
706 	    (flags & (HIO_VARIABLE | HIO_RELATIVE)) != HIO_VARIABLE)
707 		return (HMT_TYPE_UNSUPPORTED);
708 
709 	cont_count_max = ai.max;
710 
711 	/* Parse features for button type usage */
712 	if (hidbus_locate(d_ptr, d_len,
713 	    HID_USAGE2(HUP_DIGITIZERS, HUD_BUTTON_TYPE), hid_feature,
714 	    tlc_index, 0, &sc->btn_type_loc, &flags, &sc->btn_type_rid, NULL)
715 	    && (flags & (HIO_VARIABLE | HIO_RELATIVE)) != HIO_VARIABLE)
716 		sc->btn_type_rid = 0;
717 
718 	/* Parse features for THQA certificate report ID */
719 	hidbus_locate(d_ptr, d_len, HID_USAGE2(HUP_MICROSOFT, HUMS_THQA_CERT),
720 	    hid_feature, tlc_index, 0, NULL, NULL, &sc->thqa_cert_rid, NULL);
721 
722 	/* Parse input for other parameters */
723 	hd = hid_start_parse(d_ptr, d_len, 1 << hid_input);
724 	HIDBUS_FOREACH_ITEM(hd, &hi, tlc_index) {
725 		switch (hi.kind) {
726 		case hid_collection:
727 			if (hi.collevel == 2 &&
728 			    hi.usage == HID_USAGE2(HUP_DIGITIZERS, HUD_FINGER))
729 				finger_coll = true;
730 			break;
731 		case hid_endcollection:
732 			if (hi.collevel == 1 && finger_coll) {
733 				finger_coll = false;
734 				cont++;
735 			}
736 			break;
737 		case hid_input:
738 			/*
739 			 * Ensure that all usages belong to the same report
740 			 */
741 			if (HMT_HI_ABSOLUTE(hi) &&
742 			    (report_id == 0 || report_id == hi.report_ID))
743 				report_id = hi.report_ID;
744 			else
745 				break;
746 
747 			if (left_btn == 2 &&
748 			    hi.usage == HID_USAGE2(HUP_BUTTON, 1)) {
749 				has_int_button = true;
750 				sc->int_btn_loc = hi.loc;
751 				break;
752 			}
753 			if (hi.usage >= HID_USAGE2(HUP_BUTTON, left_btn) &&
754 			    hi.usage <= HID_USAGE2(HUP_BUTTON, HMT_BTN_MAX)) {
755 				btn = (hi.usage & 0xFFFF) - left_btn;
756 				setbit(sc->buttons, btn);
757 				sc->btn_loc[btn] = hi.loc;
758 				if (btn >= sc->max_button)
759 					sc->max_button = btn + 1;
760 				break;
761 			}
762 			if (hi.usage ==
763 			    HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTCOUNT)) {
764 				cont_count_found = true;
765 				sc->cont_count_loc = hi.loc;
766 				break;
767 			}
768 			if (hi.usage ==
769 			    HID_USAGE2(HUP_DIGITIZERS, HUD_SCAN_TIME)) {
770 				scan_time_found = true;
771 				sc->scan_time_loc = hi.loc;
772 				sc->scan_time_max = hi.logical_maximum;
773 				break;
774 			}
775 
776 			if (!finger_coll || hi.collevel != 2)
777 				break;
778 			if (cont >= MAX_MT_SLOTS) {
779 				DPRINTF("Finger %zu ignored\n", cont);
780 				break;
781 			}
782 
783 			for (i = 0; i < HMT_N_USAGES; i++) {
784 				if (hi.usage == hmt_hid_map[i].usage) {
785 					/*
786 					 * HUG_X usage is an array mapped to
787 					 * both ABS_MT_POSITION and ABS_MT_TOOL
788 					 * events. So don`t stop search if we
789 					 * already have HUG_X mapping done.
790 					 */
791 					if (sc->locs[cont][i].size)
792 						continue;
793 					sc->locs[cont][i] = hi.loc;
794 					/*
795 					 * Hid parser returns valid logical and
796 					 * physical sizes for first finger only
797 					 * at least on ElanTS 0x04f3:0x0012.
798 					 */
799 					if (cont > 0)
800 						break;
801 					setbit(sc->caps, i);
802 					sc->ai[i] = (struct hid_absinfo) {
803 					    .max = hi.logical_maximum,
804 					    .min = hi.logical_minimum,
805 					    .res = hid_item_resolution(&hi),
806 					};
807 					break;
808 				}
809 			}
810 			break;
811 		default:
812 			break;
813 		}
814 	}
815 	hid_end_parse(hd);
816 
817 	/* Check for required HID Usages */
818 	if ((!cont_count_found && cont != 1) || cont == 0)
819 		return (HMT_TYPE_UNSUPPORTED);
820 	for (i = 0; i < HMT_N_USAGES; i++) {
821 		if (hmt_hid_map[i].required && isclr(sc->caps, i))
822 			return (HMT_TYPE_UNSUPPORTED);
823 	}
824 
825 	/* Touchpads must have at least one button */
826 	if (type == HMT_TYPE_TOUCHPAD && !sc->max_button && !has_int_button)
827 		return (HMT_TYPE_UNSUPPORTED);
828 
829 	/*
830 	 * According to specifications 'Contact Count Maximum' should be read
831 	 * from Feature Report rather than from HID descriptor. Set sane
832 	 * default value now to handle the case of 'Get Report' request failure
833 	 */
834 	if (cont_count_max < 1)
835 		cont_count_max = cont;
836 
837 	/* Report touch orientation if both width and height are supported */
838 	if (isset(sc->caps, HMT_WIDTH) && isset(sc->caps, HMT_HEIGHT)) {
839 		setbit(sc->caps, HMT_ORIENTATION);
840 		sc->ai[HMT_ORIENTATION].max = 1;
841 	}
842 
843 	sc->cont_max_rlen = hid_report_size(d_ptr, d_len, hid_feature,
844 	    sc->cont_max_rid);
845 	if (sc->btn_type_rid > 0)
846 		sc->btn_type_rlen = hid_report_size(d_ptr, d_len,
847 		    hid_feature, sc->btn_type_rid);
848 	if (sc->thqa_cert_rid > 0)
849 		sc->thqa_cert_rlen = hid_report_size(d_ptr, d_len,
850 		    hid_feature, sc->thqa_cert_rid);
851 
852 	sc->report_id = report_id;
853 	sc->cont_count_max = cont_count_max;
854 	sc->nconts_per_report = cont;
855 	sc->has_int_button = has_int_button;
856 	sc->has_cont_count = cont_count_found;
857 	sc->has_scan_time = scan_time_found;
858 
859 	return (type);
860 }
861 
862 static int
863 hmt_set_input_mode(struct hmt_softc *sc, enum hconf_input_mode mode)
864 {
865 	devclass_t hconf_devclass;
866 	device_t hconf;
867 	int  err;
868 
869 	bus_topo_assert();
870 
871 	/* Find touchpad's configuration TLC */
872 	hconf = hidbus_find_child(device_get_parent(sc->dev),
873 	    HID_USAGE2(HUP_DIGITIZERS, HUD_CONFIG));
874 	if (hconf == NULL)
875 		return (ENXIO);
876 
877 	/* Ensure that hconf driver is attached to configuration TLC */
878 	if (device_is_alive(hconf) == 0)
879 		device_probe_and_attach(hconf);
880 	if (device_is_attached(hconf) == 0)
881 		return (ENXIO);
882 	hconf_devclass = devclass_find("hconf");
883 	if (device_get_devclass(hconf) != hconf_devclass)
884 		return (ENXIO);
885 
886 	/* hconf_set_input_mode can drop the topo lock while sleeping */
887 	device_busy(hconf);
888 	err = hconf_set_input_mode(hconf, mode);
889 	device_unbusy(hconf);
890 
891 	return (err);
892 }
893 
894 static device_method_t hmt_methods[] = {
895 	DEVMETHOD(device_probe,		hmt_probe),
896 	DEVMETHOD(device_attach,	hmt_attach),
897 	DEVMETHOD(device_detach,	hmt_detach),
898 
899 	DEVMETHOD_END
900 };
901 
902 static driver_t hmt_driver = {
903 	.name = "hmt",
904 	.methods = hmt_methods,
905 	.size = sizeof(struct hmt_softc),
906 };
907 
908 DRIVER_MODULE(hmt, hidbus, hmt_driver, NULL, NULL);
909 MODULE_DEPEND(hmt, hidbus, 1, 1, 1);
910 MODULE_DEPEND(hmt, hid, 1, 1, 1);
911 MODULE_DEPEND(hmt, hconf, 1, 1, 1);
912 MODULE_DEPEND(hmt, evdev, 1, 1, 1);
913 MODULE_VERSION(hmt, 1);
914 HID_PNP_INFO(hmt_devs);
915