xref: /openbsd/sys/dev/hid/hidmt.c (revision 771a028d)
1 /* $OpenBSD: hidmt.c,v 1.13 2022/10/16 20:17:08 bru Exp $ */
2 /*
3  * HID multitouch driver for devices conforming to Windows Precision Touchpad
4  * standard
5  *
6  * https://msdn.microsoft.com/en-us/library/windows/hardware/dn467314%28v=vs.85%29.aspx
7  * https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/touchscreen-packet-reporting-modes
8  *
9  * Copyright (c) 2016 joshua stein <jcs@openbsd.org>
10  *
11  * Permission to use, copy, modify, and distribute this software for any
12  * purpose with or without fee is hereby granted, provided that the above
13  * copyright notice and this permission notice appear in all copies.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
16  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
17  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
18  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
21  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22  */
23 
24 #include <sys/param.h>
25 #include <sys/systm.h>
26 #include <sys/kernel.h>
27 #include <sys/device.h>
28 #include <sys/ioctl.h>
29 #include <sys/malloc.h>
30 
31 #include <dev/wscons/wsconsio.h>
32 #include <dev/wscons/wsmousevar.h>
33 
34 #include <dev/hid/hid.h>
35 #include <dev/hid/hidmtvar.h>
36 
37 /* #define HIDMT_DEBUG */
38 
39 #ifdef HIDMT_DEBUG
40 #define DPRINTF(x) printf x
41 #else
42 #define DPRINTF(x)
43 #endif
44 
45 #define HID_UNIT_CM	0x11
46 #define HID_UNIT_INCH	0x13
47 
48 /*
49  * Calculate the horizontal or vertical resolution, in device units per
50  * millimeter.
51  *
52  * With the length unit specified by the descriptor (centimeter or inch),
53  * the result is:
54  *     (logical_maximum - logical_minimum) / ((physical_maximum -
55  *         physical_minimum) * 10^unit_exponent)
56  *
57  * The descriptors should encode the unit exponent as a signed half-byte.
58  * However, this function accepts the values from -8 to -1 in both the
59  * 4-bit format and the usual encoding.  Other values beyond the 4-bit
60  * range are treated as undefined.  Possibly a misinterpretation of
61  * section 6.2.2.7 of the HID specification (v1.11) has been turned into
62  * a standard here, see (from www.usb.org)
63  *     HUTRR39: "HID Sensor Usage Tables", sect. 3.9, 3.10, 4.2.1
64  * for an official exegesis and
65  *     https://patchwork.kernel.org/patch/3033191
66  * for details and a different view.
67  */
68 int
hidmt_get_resolution(struct hid_item * h)69 hidmt_get_resolution(struct hid_item *h)
70 {
71 	int log_extent, phy_extent, exponent;
72 
73 	if (h->unit != HID_UNIT_CM && h->unit != HID_UNIT_INCH)
74 		return (0);
75 
76 	log_extent = h->logical_maximum - h->logical_minimum;
77 	phy_extent = h->physical_maximum - h->physical_minimum;
78 	if (log_extent <= 0 || phy_extent <= 0)
79 		return (0);
80 
81 	exponent = h->unit_exponent;
82 	if (exponent < -8 || exponent > 15)		/* See above. */
83 		return (0);
84 	if (exponent > 7)
85 		exponent -= 16;
86 
87 	for (; exponent < 0 && log_extent <= INT_MAX / 10; exponent++)
88 		log_extent *= 10;
89 	for (; exponent > 0 && phy_extent <= INT_MAX / 10; exponent--)
90 		phy_extent *= 10;
91 	if (exponent != 0)
92 		return (0);
93 
94 	if (h->unit == HID_UNIT_INCH) {			/* Map inches to mm. */
95 		if ((phy_extent > INT_MAX / 127)
96 		    || (log_extent > INT_MAX / 5))
97 			return (0);
98 		log_extent *= 5;
99 		phy_extent *= 127;
100 	} else {					/* Map cm to mm. */
101 		if (phy_extent > INT_MAX / 10)
102 			return (0);
103 		phy_extent *= 10;
104 	}
105 
106 	return (log_extent / phy_extent);
107 }
108 
109 int
hidmt_setup(struct device * self,struct hidmt * mt,void * desc,int dlen)110 hidmt_setup(struct device *self, struct hidmt *mt, void *desc, int dlen)
111 {
112 	struct hid_location cap;
113 	int32_t d;
114 	uint8_t *rep;
115 	int capsize;
116 
117 	struct hid_data *hd;
118 	struct hid_item h;
119 
120 	mt->sc_device = self;
121 	mt->sc_rep_input_size = hid_report_size(desc, dlen, hid_input,
122 	    mt->sc_rep_input);
123 
124 	mt->sc_minx = mt->sc_miny = mt->sc_maxx = mt->sc_maxy = 0;
125 
126 	capsize = hid_report_size(desc, dlen, hid_feature, mt->sc_rep_cap);
127 	rep = malloc(capsize, M_DEVBUF, M_NOWAIT | M_ZERO);
128 
129 	if (mt->hidev_report_type_conv == NULL)
130 		panic("no report type conversion function");
131 
132 	if (mt->hidev_get_report(mt->sc_device,
133 	    mt->hidev_report_type_conv(hid_feature), mt->sc_rep_cap,
134 	    rep, capsize)) {
135 		printf("\n%s: failed getting capability report\n",
136 		    self->dv_xname);
137 		return 1;
138 	}
139 
140 	/* find maximum number of contacts being reported per input report */
141 	mt->sc_num_contacts = HIDMT_MAX_CONTACTS;
142 	if (hid_locate(desc, dlen, HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACT_MAX),
143 	    mt->sc_rep_cap, hid_feature, &cap, NULL)) {
144 		d = hid_get_udata(rep, capsize, &cap);
145 		if (d > HIDMT_MAX_CONTACTS)
146 			printf("\n%s: contacts %d > max %d\n", self->dv_xname,
147 			    d, HIDMT_MAX_CONTACTS);
148 		else
149 			mt->sc_num_contacts = d;
150 	}
151 
152 	/* find whether this is a clickpad or not */
153 	if (hid_locate(desc, dlen, HID_USAGE2(HUP_DIGITIZERS, HUD_BUTTON_TYPE),
154 	    mt->sc_rep_cap, hid_feature, &cap, NULL)) {
155 		d = hid_get_udata(rep, capsize, &cap);
156 		mt->sc_clickpad = (d == 0);
157 	} else if (hid_locate(desc, dlen, HID_USAGE2(HUP_BUTTON, 1),
158 	    mt->sc_rep_input, hid_input, &cap, NULL) ||
159 	    !hid_locate(desc, dlen, HID_USAGE2(HUP_BUTTON, 2),
160 	    mt->sc_rep_input, hid_input, &cap, NULL) ||
161 	    !hid_locate(desc, dlen, HID_USAGE2(HUP_BUTTON, 3),
162 	    mt->sc_rep_input, hid_input, &cap, NULL)) {
163 		mt->sc_clickpad = 1;
164 	}
165 	/*
166 	 * Walk HID descriptor and store usages we care about to know what to
167 	 * pluck out of input reports.
168 	 */
169 
170 	SIMPLEQ_INIT(&mt->sc_inputs);
171 
172 	hd = hid_start_parse(desc, dlen, hid_input);
173 	while (hid_get_item(hd, &h)) {
174 		struct hidmt_data *input;
175 
176 		if (h.report_ID != mt->sc_rep_input)
177 			continue;
178 		if (h.kind != hid_input)
179 			continue;
180 
181 		switch (h.usage) {
182 		/* contact level usages */
183 		case HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_X):
184 			if (h.logical_maximum - h.logical_minimum) {
185 				mt->sc_minx = h.logical_minimum;
186 				mt->sc_maxx = h.logical_maximum;
187 				mt->sc_resx = hidmt_get_resolution(&h);
188 			}
189 			break;
190 		case HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y):
191 			if (h.logical_maximum - h.logical_minimum) {
192 				mt->sc_miny = h.logical_minimum;
193 				mt->sc_maxy = h.logical_maximum;
194 				mt->sc_resy = hidmt_get_resolution(&h);
195 			}
196 			break;
197 		case HID_USAGE2(HUP_DIGITIZERS, HUD_TIP_SWITCH):
198 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONFIDENCE):
199 		case HID_USAGE2(HUP_DIGITIZERS, HUD_WIDTH):
200 		case HID_USAGE2(HUP_DIGITIZERS, HUD_HEIGHT):
201 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTID):
202 
203 		/* report level usages */
204 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTCOUNT):
205 		case HID_USAGE2(HUP_BUTTON, 0x01):
206 		case HID_USAGE2(HUP_BUTTON, 0x02):
207 		case HID_USAGE2(HUP_BUTTON, 0x03):
208 			break;
209 		default:
210 			continue;
211 		}
212 
213 		input = malloc(sizeof(*input), M_DEVBUF, M_NOWAIT | M_ZERO);
214 		memcpy(&input->loc, &h.loc, sizeof(struct hid_location));
215 		input->usage = h.usage;
216 
217 		SIMPLEQ_INSERT_TAIL(&mt->sc_inputs, input, entry);
218 	}
219 	hid_end_parse(hd);
220 
221 	if (mt->sc_maxx <= 0 || mt->sc_maxy <= 0) {
222 		printf("\n%s: invalid max X/Y %d/%d\n", self->dv_xname,
223 		    mt->sc_maxx, mt->sc_maxy);
224 		return 1;
225 	}
226 
227 	if (hidmt_set_input_mode(mt, HIDMT_INPUT_MODE_MT_TOUCHPAD)) {
228 		printf("\n%s: switch to multitouch mode failed\n",
229 		    self->dv_xname);
230 		return 1;
231 	}
232 
233 	return 0;
234 }
235 
236 void
hidmt_configure(struct hidmt * mt)237 hidmt_configure(struct hidmt *mt)
238 {
239 	struct wsmousehw *hw;
240 
241 	if (mt->sc_wsmousedev == NULL)
242 		return;
243 
244 	hw = wsmouse_get_hw(mt->sc_wsmousedev);
245 	hw->type = WSMOUSE_TYPE_TOUCHPAD;
246 	hw->hw_type = (mt->sc_clickpad
247 	    ? WSMOUSEHW_CLICKPAD : WSMOUSEHW_TOUCHPAD);
248 	hw->x_min = mt->sc_minx;
249 	hw->x_max = mt->sc_maxx;
250 	hw->y_min = mt->sc_miny;
251 	hw->y_max = mt->sc_maxy;
252 	hw->h_res = mt->sc_resx;
253 	hw->v_res = mt->sc_resy;
254 	hw->mt_slots = HIDMT_MAX_CONTACTS;
255 
256 	wsmouse_configure(mt->sc_wsmousedev, NULL, 0);
257 }
258 
259 void
hidmt_attach(struct hidmt * mt,const struct wsmouse_accessops * ops)260 hidmt_attach(struct hidmt *mt, const struct wsmouse_accessops *ops)
261 {
262 	struct wsmousedev_attach_args a;
263 
264 	printf(": %spad, %d contact%s\n",
265 	    (mt->sc_clickpad ? "click" : "touch"), mt->sc_num_contacts,
266 	    (mt->sc_num_contacts == 1 ? "" : "s"));
267 
268 	a.accessops = ops;
269 	a.accesscookie = mt->sc_device;
270 	mt->sc_wsmousedev = config_found(mt->sc_device, &a, wsmousedevprint);
271 	hidmt_configure(mt);
272 }
273 
274 int
hidmt_detach(struct hidmt * mt,int flags)275 hidmt_detach(struct hidmt *mt, int flags)
276 {
277 	int rv = 0;
278 
279 	if (mt->sc_wsmousedev != NULL)
280 		rv = config_detach(mt->sc_wsmousedev, flags);
281 
282 	return (rv);
283 }
284 
285 int
hidmt_set_input_mode(struct hidmt * mt,uint16_t mode)286 hidmt_set_input_mode(struct hidmt *mt, uint16_t mode)
287 {
288 	if (mt->hidev_report_type_conv == NULL)
289 		panic("no report type conversion function");
290 
291 	return mt->hidev_set_report(mt->sc_device,
292 	    mt->hidev_report_type_conv(hid_feature),
293 	    mt->sc_rep_config, &mode, sizeof(mode));
294 }
295 
296 void
hidmt_input(struct hidmt * mt,uint8_t * data,u_int len)297 hidmt_input(struct hidmt *mt, uint8_t *data, u_int len)
298 {
299 	struct hidmt_data *hi;
300 	struct hidmt_contact hc;
301 	int32_t d, firstu = 0;
302 	int contactcount = 0, seencontacts = 0, tips = 0, buttons = 0, i, s, z;
303 
304 	if (len != mt->sc_rep_input_size) {
305 		DPRINTF(("%s: %s: length %d not %d, ignoring\n",
306 		    mt->sc_device->dv_xname, __func__, len,
307 		    mt->sc_rep_input_size));
308 		return;
309 	}
310 
311 	/*
312 	 * "In Parallel mode, devices report all contact information in a
313 	 * single packet. Each physical contact is represented by a logical
314 	 * collection that is embedded in the top-level collection."
315 	 *
316 	 * Since additional contacts that were not present will still be in the
317 	 * report with contactid=0 but contactids are zero-based, find
318 	 * contactcount first.
319 	 */
320 	SIMPLEQ_FOREACH(hi, &mt->sc_inputs, entry) {
321 		if (hi->usage == HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTCOUNT))
322 			contactcount = hid_get_udata(data, len, &hi->loc);
323 	}
324 
325 	if (contactcount)
326 		mt->sc_cur_contactcount = contactcount;
327 	else {
328 		/*
329 		* "In Hybrid mode, the number of contacts that can be reported
330 		* in one report is less than the maximum number of contacts
331 		* that the device supports. For example, a device that supports
332 		* a maximum of 4 concurrent physical contacts, can set up its
333 		* top-level collection to deliver a maximum of two contacts in
334 		* one report. If four contact points are present, the device
335 		* can break these up into two serial reports that deliver two
336 		* contacts each.
337 		*
338 		* "When a device delivers data in this manner, the Contact
339 		* Count usage value in the first report should reflect the
340 		* total number of contacts that are being delivered in the
341 		* hybrid reports. The other serial reports should have a
342 		* contact count of zero (0)."
343 		*/
344 		contactcount = mt->sc_cur_contactcount;
345 	}
346 
347 	if (!contactcount) {
348 		DPRINTF(("%s: %s: no contactcount in report\n",
349 		    mt->sc_device->dv_xname, __func__));
350 		return;
351 	}
352 
353 	/*
354 	 * Walk through each input we know about and fetch its data from the
355 	 * report, storing it in a temporary contact.  Once we see our first
356 	 * usage again, we'll know we saw all usages being presented for that
357 	 * contact.
358 	 */
359 	bzero(&hc, sizeof(struct hidmt_contact));
360 	SIMPLEQ_FOREACH(hi, &mt->sc_inputs, entry) {
361 		d = hid_get_udata(data, len, &hi->loc);
362 
363 		if (firstu && hi->usage == firstu) {
364 			if (seencontacts < contactcount) {
365 				hc.seen = 1;
366 				i = wsmouse_id_to_slot(
367 				    mt->sc_wsmousedev, hc.contactid);
368 				if (i >= 0)
369 					memcpy(&mt->sc_contacts[i], &hc,
370 					    sizeof(struct hidmt_contact));
371 				seencontacts++;
372 			}
373 
374 			bzero(&hc, sizeof(struct hidmt_contact));
375 		}
376 		else if (!firstu)
377 			firstu = hi->usage;
378 
379 		switch (hi->usage) {
380 		case HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_X):
381 			hc.x = d;
382 			break;
383 		case HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y):
384 			if (mt->sc_flags & HIDMT_REVY)
385 				hc.y = mt->sc_maxy - d;
386 			else
387 				hc.y = d;
388 			break;
389 		case HID_USAGE2(HUP_DIGITIZERS, HUD_TIP_SWITCH):
390 			hc.tip = d;
391 			if (d)
392 				tips++;
393 			break;
394 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONFIDENCE):
395 			hc.confidence = d;
396 			break;
397 		case HID_USAGE2(HUP_DIGITIZERS, HUD_WIDTH):
398 			hc.width = d;
399 			break;
400 		case HID_USAGE2(HUP_DIGITIZERS, HUD_HEIGHT):
401 			hc.height = d;
402 			break;
403 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTID):
404 			hc.contactid = d;
405 			break;
406 
407 		/* these will only appear once per report */
408 		case HID_USAGE2(HUP_DIGITIZERS, HUD_CONTACTCOUNT):
409 			if (d)
410 				contactcount = d;
411 			break;
412 		case HID_USAGE2(HUP_BUTTON, 0x01):
413 		case HID_USAGE2(HUP_BUTTON, 0x02):
414 			if (d != 0)
415 				buttons |= 1;
416 			break;
417 		case HID_USAGE2(HUP_BUTTON, 0x03):
418 			if (d != 0)
419 				buttons |= 1 << 2;
420 			break;
421 		}
422 	}
423 	if (seencontacts < contactcount) {
424 		hc.seen = 1;
425 		i = wsmouse_id_to_slot(mt->sc_wsmousedev, hc.contactid);
426 		if (i >= 0)
427 			memcpy(&mt->sc_contacts[i], &hc,
428 			    sizeof(struct hidmt_contact));
429 		seencontacts++;
430 	}
431 
432 	s = spltty();
433 	if (mt->sc_buttons != buttons) {
434 		wsmouse_buttons(mt->sc_wsmousedev, buttons);
435 		mt->sc_buttons = buttons;
436 	}
437 	for (i = 0; i < HIDMT_MAX_CONTACTS; i++) {
438 		if (!mt->sc_contacts[i].seen)
439 			continue;
440 
441 		mt->sc_contacts[i].seen = 0;
442 
443 		DPRINTF(("%s: %s: contact %d of %d: id %d, x %d, y %d, "
444 		    "touch %d, confidence %d, width %d, height %d "
445 		    "(button 0x%x)\n",
446 		    mt->sc_device->dv_xname, __func__,
447 		    i + 1, contactcount,
448 		    mt->sc_contacts[i].contactid,
449 		    mt->sc_contacts[i].x,
450 		    mt->sc_contacts[i].y,
451 		    mt->sc_contacts[i].tip,
452 		    mt->sc_contacts[i].confidence,
453 		    mt->sc_contacts[i].width,
454 		    mt->sc_contacts[i].height,
455 		    mt->sc_buttons));
456 
457 		if (mt->sc_contacts[i].tip && !mt->sc_contacts[i].confidence)
458 			continue;
459 
460 		/* Report width as pressure. */
461 		z = (mt->sc_contacts[i].tip
462 		    ? imax(mt->sc_contacts[i].width, 50) : 0);
463 
464 		wsmouse_mtstate(mt->sc_wsmousedev,
465 		    i, mt->sc_contacts[i].x, mt->sc_contacts[i].y, z);
466 	}
467 	wsmouse_input_sync(mt->sc_wsmousedev);
468 
469 	splx(s);
470 }
471 
472 int
hidmt_enable(struct hidmt * mt)473 hidmt_enable(struct hidmt *mt)
474 {
475 	if (mt->sc_enabled)
476 		return EBUSY;
477 
478 	mt->sc_enabled = 1;
479 
480 	return 0;
481 }
482 
483 int
hidmt_ioctl(struct hidmt * mt,u_long cmd,caddr_t data,int flag,struct proc * p)484 hidmt_ioctl(struct hidmt *mt, u_long cmd, caddr_t data, int flag,
485     struct proc *p)
486 {
487 	struct wsmouse_calibcoords *wsmc = (struct wsmouse_calibcoords *)data;
488 	int wsmode;
489 
490 	switch (cmd) {
491 	case WSMOUSEIO_GTYPE: {
492 		struct wsmousehw *hw = wsmouse_get_hw(mt->sc_wsmousedev);
493 		*(u_int *)data = hw->type;
494 		break;
495 	}
496 
497 	case WSMOUSEIO_GCALIBCOORDS:
498 		wsmc->minx = mt->sc_minx;
499 		wsmc->maxx = mt->sc_maxx;
500 		wsmc->miny = mt->sc_miny;
501 		wsmc->maxy = mt->sc_maxy;
502 		wsmc->swapxy = 0;
503 		wsmc->resx = mt->sc_resx;
504 		wsmc->resy = mt->sc_resy;
505 		break;
506 
507 	case WSMOUSEIO_SETMODE:
508 		wsmode = *(u_int *)data;
509 		if (wsmode != WSMOUSE_COMPAT && wsmode != WSMOUSE_NATIVE) {
510 			printf("%s: invalid mode %d\n",
511 			    mt->sc_device->dv_xname, wsmode);
512 			return (EINVAL);
513 		}
514 
515 		DPRINTF(("%s: changing mode to %s\n", mt->sc_device->dv_xname,
516 		    (wsmode == WSMOUSE_COMPAT ? "compat" : "native")));
517 
518 		wsmouse_set_mode(mt->sc_wsmousedev, wsmode);
519 
520 		break;
521 
522 	default:
523 		return -1;
524 	}
525 
526 	return 0;
527 }
528 
529 void
hidmt_disable(struct hidmt * mt)530 hidmt_disable(struct hidmt *mt)
531 {
532 	mt->sc_enabled = 0;
533 }
534