xref: /freebsd/sys/dev/hid/ietp.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020, 2022 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 /*
29  * Elan I2C Touchpad driver. Based on Linux driver.
30  * https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/input/mouse/elan_i2c_core.c
31  */
32 
33 #include <sys/param.h>
34 #include <sys/bus.h>
35 #include <sys/endian.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/sysctl.h>
42 #include <sys/systm.h>
43 
44 #include <dev/evdev/evdev.h>
45 #include <dev/evdev/input.h>
46 
47 #include <dev/iicbus/iic.h>
48 #include <dev/iicbus/iicbus.h>
49 
50 #define HID_DEBUG_VAR   ietp_debug
51 #include <dev/hid/hid.h>
52 #include <dev/hid/hidbus.h>
53 #include <dev/hid/hidquirk.h>
54 
55 #ifdef HID_DEBUG
56 static SYSCTL_NODE(_hw_hid, OID_AUTO, ietp, CTLFLAG_RW, 0,
57     "Elantech Touchpad");
58 static int ietp_debug = 1;
59 SYSCTL_INT(_hw_hid_ietp, OID_AUTO, debug, CTLFLAG_RWTUN,
60     &ietp_debug, 1, "Debug level");
61 #endif
62 
63 #define	IETP_PATTERN		0x0100
64 #define	IETP_UNIQUEID		0x0101
65 #define	IETP_FW_VERSION		0x0102
66 #define	IETP_IC_TYPE		0x0103
67 #define	IETP_OSM_VERSION	0x0103
68 #define	IETP_NSM_VERSION	0x0104
69 #define	IETP_TRACENUM		0x0105
70 #define	IETP_MAX_X_AXIS		0x0106
71 #define	IETP_MAX_Y_AXIS		0x0107
72 #define	IETP_RESOLUTION		0x0108
73 #define	IETP_PRESSURE		0x010A
74 
75 #define	IETP_CONTROL		0x0300
76 #define	IETP_CTRL_ABSOLUTE	0x0001
77 #define	IETP_CTRL_STANDARD	0x0000
78 
79 #define	IETP_REPORT_LEN_LO	32
80 #define	IETP_REPORT_LEN_HI	37
81 #define	IETP_MAX_FINGERS	5
82 
83 #define	IETP_REPORT_ID_LO	0x5D
84 #define	IETP_REPORT_ID_HI	0x60
85 
86 #define	IETP_TOUCH_INFO		1
87 #define	IETP_FINGER_DATA	2
88 #define	IETP_FINGER_DATA_LEN	5
89 #define	IETP_HOVER_INFO		28
90 #define	IETP_WH_DATA		31
91 
92 #define	IETP_TOUCH_LMB		(1 << 0)
93 #define	IETP_TOUCH_RMB		(1 << 1)
94 #define	IETP_TOUCH_MMB		(1 << 2)
95 
96 #define	IETP_MAX_PRESSURE	255
97 #define	IETP_FWIDTH_REDUCE	90
98 #define	IETP_FINGER_MAX_WIDTH	15
99 #define	IETP_PRESSURE_BASE	25
100 
101 struct ietp_softc {
102 	device_t		dev;
103 
104 	struct evdev_dev	*evdev;
105 	uint8_t			report_id;
106 	hid_size_t		report_len;
107 
108 	uint16_t		product_id;
109 	uint16_t		ic_type;
110 
111 	int32_t			pressure_base;
112 	uint16_t		max_x;
113 	uint16_t		max_y;
114 	uint16_t		trace_x;
115 	uint16_t		trace_y;
116 	uint16_t		res_x;		/* dots per mm */
117 	uint16_t		res_y;
118 	bool			hi_precision;
119 	bool			is_clickpad;
120 	bool			has_3buttons;
121 };
122 
123 static evdev_open_t	ietp_ev_open;
124 static evdev_close_t	ietp_ev_close;
125 static hid_intr_t	ietp_intr;
126 
127 static int		ietp_probe(struct ietp_softc *);
128 static int		ietp_attach(struct ietp_softc *);
129 static int		ietp_detach(struct ietp_softc *);
130 static int32_t		ietp_res2dpmm(uint8_t, bool);
131 
132 static device_identify_t ietp_iic_identify;
133 static device_probe_t	ietp_iic_probe;
134 static device_attach_t	ietp_iic_attach;
135 static device_detach_t	ietp_iic_detach;
136 static device_resume_t	ietp_iic_resume;
137 
138 static int		ietp_iic_read_reg(device_t, uint16_t, size_t, void *);
139 static int		ietp_iic_write_reg(device_t, uint16_t, uint16_t);
140 static int		ietp_iic_set_absolute_mode(device_t, bool);
141 
142 #define	IETP_IIC_DEV(pnp) \
143     { HID_TLC(HUP_GENERIC_DESKTOP, HUG_MOUSE), HID_BUS(BUS_I2C), HID_PNP(pnp) }
144 
145 static const struct hid_device_id ietp_iic_devs[] = {
146 	IETP_IIC_DEV("ELAN0000"),
147 	IETP_IIC_DEV("ELAN0100"),
148 	IETP_IIC_DEV("ELAN0600"),
149 	IETP_IIC_DEV("ELAN0601"),
150 	IETP_IIC_DEV("ELAN0602"),
151 	IETP_IIC_DEV("ELAN0603"),
152 	IETP_IIC_DEV("ELAN0604"),
153 	IETP_IIC_DEV("ELAN0605"),
154 	IETP_IIC_DEV("ELAN0606"),
155 	IETP_IIC_DEV("ELAN0607"),
156 	IETP_IIC_DEV("ELAN0608"),
157 	IETP_IIC_DEV("ELAN0609"),
158 	IETP_IIC_DEV("ELAN060B"),
159 	IETP_IIC_DEV("ELAN060C"),
160 	IETP_IIC_DEV("ELAN060F"),
161 	IETP_IIC_DEV("ELAN0610"),
162 	IETP_IIC_DEV("ELAN0611"),
163 	IETP_IIC_DEV("ELAN0612"),
164 	IETP_IIC_DEV("ELAN0615"),
165 	IETP_IIC_DEV("ELAN0616"),
166 	IETP_IIC_DEV("ELAN0617"),
167 	IETP_IIC_DEV("ELAN0618"),
168 	IETP_IIC_DEV("ELAN0619"),
169 	IETP_IIC_DEV("ELAN061A"),
170 	IETP_IIC_DEV("ELAN061B"),
171 	IETP_IIC_DEV("ELAN061C"),
172 	IETP_IIC_DEV("ELAN061D"),
173 	IETP_IIC_DEV("ELAN061E"),
174 	IETP_IIC_DEV("ELAN061F"),
175 	IETP_IIC_DEV("ELAN0620"),
176 	IETP_IIC_DEV("ELAN0621"),
177 	IETP_IIC_DEV("ELAN0622"),
178 	IETP_IIC_DEV("ELAN0623"),
179 	IETP_IIC_DEV("ELAN0624"),
180 	IETP_IIC_DEV("ELAN0625"),
181 	IETP_IIC_DEV("ELAN0626"),
182 	IETP_IIC_DEV("ELAN0627"),
183 	IETP_IIC_DEV("ELAN0628"),
184 	IETP_IIC_DEV("ELAN0629"),
185 	IETP_IIC_DEV("ELAN062A"),
186 	IETP_IIC_DEV("ELAN062B"),
187 	IETP_IIC_DEV("ELAN062C"),
188 	IETP_IIC_DEV("ELAN062D"),
189 	IETP_IIC_DEV("ELAN062E"),	/* Lenovo V340 Whiskey Lake U */
190 	IETP_IIC_DEV("ELAN062F"),	/* Lenovo V340 Comet Lake U */
191 	IETP_IIC_DEV("ELAN0631"),
192 	IETP_IIC_DEV("ELAN0632"),
193 	IETP_IIC_DEV("ELAN0633"),	/* Lenovo S145 */
194 	IETP_IIC_DEV("ELAN0634"),	/* Lenovo V340 Ice lake */
195 	IETP_IIC_DEV("ELAN0635"),	/* Lenovo V1415-IIL */
196 	IETP_IIC_DEV("ELAN0636"),	/* Lenovo V1415-Dali */
197 	IETP_IIC_DEV("ELAN0637"),	/* Lenovo V1415-IGLR */
198 	IETP_IIC_DEV("ELAN1000"),
199 };
200 
201 static uint8_t const ietp_dummy_rdesc[] = {
202 	0x05, HUP_GENERIC_DESKTOP,	/* Usage Page (Generic Desktop Ctrls)	*/
203 	0x09, HUG_MOUSE,		/* Usage (Mouse)			*/
204 	0xA1, 0x01,			/* Collection (Application)		*/
205 	0x09, 0x01,			/*   Usage (0x01)			*/
206 	0x95, IETP_REPORT_LEN_LO,	/*   Report Count (IETP_REPORT_LEN_LO)	*/
207 	0x75, 0x08,			/*   Report Size (8)			*/
208 	0x81, 0x02,			/*   Input (Data,Var,Abs)		*/
209 	0xC0,				/* End Collection			*/
210 };
211 
212 static const struct evdev_methods ietp_evdev_methods = {
213 	.ev_open = &ietp_ev_open,
214 	.ev_close = &ietp_ev_close,
215 };
216 
217 static int
218 ietp_ev_open(struct evdev_dev *evdev)
219 {
220 	return (hid_intr_start(evdev_get_softc(evdev)));
221 }
222 
223 static int
224 ietp_ev_close(struct evdev_dev *evdev)
225 {
226 	return (hid_intr_stop(evdev_get_softc(evdev)));
227 }
228 
229 static int
230 ietp_probe(struct ietp_softc *sc)
231 {
232 	if (hidbus_find_child(device_get_parent(sc->dev),
233 	    HID_USAGE2(HUP_DIGITIZERS, HUD_TOUCHPAD)) != NULL) {
234 		DPRINTFN(5, "Ignore HID-compatible touchpad on %s\n",
235 		    device_get_nameunit(device_get_parent(sc->dev)));
236 		return (ENXIO);
237 	}
238 
239 	device_set_desc(sc->dev, "Elan Touchpad");
240 
241 	return (BUS_PROBE_DEFAULT);
242 }
243 
244 static int
245 ietp_attach(struct ietp_softc *sc)
246 {
247 	const struct hid_device_info *hw = hid_get_device_info(sc->dev);
248 	void *d_ptr;
249 	hid_size_t d_len;
250 	int32_t minor, major;
251 	int error;
252 
253 	sc->report_id = sc->hi_precision ?
254 	    IETP_REPORT_ID_HI : IETP_REPORT_ID_LO;
255 	sc->report_len = sc->hi_precision ?
256 	    IETP_REPORT_LEN_HI : IETP_REPORT_LEN_LO;
257 
258 	/* Try to detect 3-rd button by relative mouse TLC */
259 	if (!sc->is_clickpad) {
260 		error = hid_get_report_descr(sc->dev, &d_ptr, &d_len);
261 		if (error != 0) {
262 			device_printf(sc->dev, "could not retrieve report "
263 			    "descriptor from device: %d\n", error);
264 			return (ENXIO);
265 		}
266 		if (hidbus_locate(d_ptr, d_len, HID_USAGE2(HUP_BUTTON, 3),
267 		    hid_input, hidbus_get_index(sc->dev), 0, NULL, NULL, NULL,
268 		    NULL))
269 			sc->has_3buttons = true;
270 	}
271 
272 	sc->evdev = evdev_alloc();
273 	evdev_set_name(sc->evdev, device_get_desc(sc->dev));
274 	evdev_set_phys(sc->evdev, device_get_nameunit(sc->dev));
275 	evdev_set_id(sc->evdev, hw->idBus, hw->idVendor, hw->idProduct,
276 	    hw->idVersion);
277 	evdev_set_serial(sc->evdev, hw->serial);
278 	evdev_set_methods(sc->evdev, sc->dev, &ietp_evdev_methods);
279 	evdev_set_flag(sc->evdev, EVDEV_FLAG_MT_STCOMPAT);
280 	evdev_set_flag(sc->evdev, EVDEV_FLAG_EXT_EPOCH); /* hidbus child */
281 
282 	evdev_support_event(sc->evdev, EV_SYN);
283 	evdev_support_event(sc->evdev, EV_ABS);
284 	evdev_support_event(sc->evdev, EV_KEY);
285 	evdev_support_prop(sc->evdev, INPUT_PROP_POINTER);
286 	evdev_support_key(sc->evdev, BTN_LEFT);
287 	if (sc->is_clickpad) {
288 		evdev_support_prop(sc->evdev, INPUT_PROP_BUTTONPAD);
289 	} else {
290 		evdev_support_key(sc->evdev, BTN_RIGHT);
291 		if (sc->has_3buttons)
292 			evdev_support_key(sc->evdev, BTN_MIDDLE);
293 	}
294 
295 	major = IETP_FINGER_MAX_WIDTH * MAX(sc->trace_x, sc->trace_y);
296 	minor = IETP_FINGER_MAX_WIDTH * MIN(sc->trace_x, sc->trace_y);
297 
298 	evdev_support_abs(sc->evdev, ABS_MT_SLOT,
299 	    0, IETP_MAX_FINGERS - 1, 0, 0, 0);
300 	evdev_support_abs(sc->evdev, ABS_MT_TRACKING_ID,
301 	    -1, IETP_MAX_FINGERS - 1, 0, 0, 0);
302 	evdev_support_abs(sc->evdev, ABS_MT_POSITION_X,
303 	    0, sc->max_x, 0, 0, sc->res_x);
304 	evdev_support_abs(sc->evdev, ABS_MT_POSITION_Y,
305 	    0, sc->max_y, 0, 0, sc->res_y);
306 	evdev_support_abs(sc->evdev, ABS_MT_PRESSURE,
307 	    0, IETP_MAX_PRESSURE, 0, 0, 0);
308 	evdev_support_abs(sc->evdev, ABS_MT_ORIENTATION, 0, 1, 0, 0, 0);
309 	evdev_support_abs(sc->evdev, ABS_MT_TOUCH_MAJOR, 0, major, 0, 0, 0);
310 	evdev_support_abs(sc->evdev, ABS_MT_TOUCH_MINOR, 0, minor, 0, 0, 0);
311 	evdev_support_abs(sc->evdev, ABS_DISTANCE, 0, 1, 0, 0, 0);
312 
313 	error = evdev_register(sc->evdev);
314 	if (error != 0) {
315 		ietp_detach(sc);
316 		return (ENOMEM);
317 	}
318 
319 	hidbus_set_intr(sc->dev, ietp_intr, sc);
320 
321 	device_printf(sc->dev, "[%d:%d], %s\n", sc->max_x, sc->max_y,
322 	    sc->is_clickpad ? "clickpad" :
323 	    sc->has_3buttons ? "3 buttons" : "2 buttons");
324 
325 	return (0);
326 }
327 
328 static int
329 ietp_detach(struct ietp_softc *sc)
330 {
331 	evdev_free(sc->evdev);
332 
333 	return (0);
334 }
335 
336 static void
337 ietp_intr(void *context, void *buf, hid_size_t len)
338 {
339 	struct ietp_softc *sc = context;
340 	union evdev_mt_slot slot_data;
341 	uint8_t *report, *fdata;
342 	int32_t finger;
343 	int32_t x, y, w, h, wh;
344 
345 	/* we seem to get 0 length reports sometimes, ignore them */
346 	if (len == 0)
347 		return;
348 	if (len != sc->report_len) {
349 		DPRINTF("wrong report length (%d vs %d expected)", len, sc->report_len);
350 		return;
351 	}
352 
353 	report = buf;
354 	if (*report != sc->report_id)
355 		return;
356 
357 	evdev_push_key(sc->evdev, BTN_LEFT,
358 	    report[IETP_TOUCH_INFO] & IETP_TOUCH_LMB);
359 	evdev_push_key(sc->evdev, BTN_MIDDLE,
360 	    report[IETP_TOUCH_INFO] & IETP_TOUCH_MMB);
361 	evdev_push_key(sc->evdev, BTN_RIGHT,
362 	    report[IETP_TOUCH_INFO] & IETP_TOUCH_RMB);
363 	evdev_push_abs(sc->evdev, ABS_DISTANCE,
364 	    (report[IETP_HOVER_INFO] & 0x40) >> 6);
365 
366 	for (finger = 0, fdata = report + IETP_FINGER_DATA;
367 	     finger < IETP_MAX_FINGERS;
368 	     finger++, fdata += IETP_FINGER_DATA_LEN) {
369 		if ((report[IETP_TOUCH_INFO] & (1 << (finger + 3))) != 0) {
370 			if (sc->hi_precision) {
371 				x = fdata[0] << 8 | fdata[1];
372 				y = fdata[2] << 8 | fdata[3];
373 				wh = report[IETP_WH_DATA + finger];
374 			} else {
375 				x = (fdata[0] & 0xf0) << 4 | fdata[1];
376 				y = (fdata[0] & 0x0f) << 8 | fdata[2];
377 				wh = fdata[3];
378 			}
379 
380 			if (x > sc->max_x || y > sc->max_y) {
381 				DPRINTF("[%d] x=%d y=%d over max (%d, %d)",
382 				    finger, x, y, sc->max_x, sc->max_y);
383 				continue;
384 			}
385 
386 			/* Reduce trace size to not treat large finger as palm */
387 			w = (wh & 0x0F) * (sc->trace_x - IETP_FWIDTH_REDUCE);
388 			h = (wh >> 4) * (sc->trace_y - IETP_FWIDTH_REDUCE);
389 
390 			slot_data = (union evdev_mt_slot) {
391 				.id = finger,
392 				.x = x,
393 				.y = sc->max_y - y,
394 				.p = MIN((int32_t)fdata[4] + sc->pressure_base,
395 				    IETP_MAX_PRESSURE),
396 				.ori = w > h ? 1 : 0,
397 				.maj = MAX(w, h),
398 				.min = MIN(w, h),
399 			};
400 			evdev_mt_push_slot(sc->evdev, finger, &slot_data);
401 		} else {
402 			evdev_push_abs(sc->evdev, ABS_MT_SLOT, finger);
403 			evdev_push_abs(sc->evdev, ABS_MT_TRACKING_ID, -1);
404 		}
405 	}
406 
407 	evdev_sync(sc->evdev);
408 }
409 
410 static int32_t
411 ietp_res2dpmm(uint8_t res, bool hi_precision)
412 {
413 	int32_t dpi;
414 
415 	dpi = hi_precision ? 300 + res * 100 : 790 + res * 10;
416 
417 	return (dpi * 10 /254);
418 }
419 
420 static void
421 ietp_iic_identify(driver_t *driver, device_t parent)
422 {
423 	void *d_ptr;
424 	hid_size_t d_len;
425 	int isize;
426 	uint8_t iid;
427 
428 	if (HIDBUS_LOOKUP_ID(parent, ietp_iic_devs) == NULL)
429 		return;
430 	if (hid_get_report_descr(parent, &d_ptr, &d_len) != 0)
431 		return;
432 
433 	/*
434 	 * Some Elantech trackpads have a mangled HID report descriptor, which
435 	 * reads as having an incorrect input size (i.e. < IETP_REPORT_LEN_LO).
436 	 * If the input size is incorrect, load a dummy report descriptor.
437 	 */
438 
439 	isize = hid_report_size_max(d_ptr, d_len, hid_input, &iid);
440 	if (isize >= IETP_REPORT_LEN_LO)
441 		return;
442 
443 	hid_set_report_descr(parent, ietp_dummy_rdesc,
444 	    sizeof(ietp_dummy_rdesc));
445 }
446 
447 static int
448 ietp_iic_probe(device_t dev)
449 {
450 	struct ietp_softc *sc = device_get_softc(dev);
451 	device_t iichid;
452 	int error;
453 
454 	error = HIDBUS_LOOKUP_DRIVER_INFO(dev, ietp_iic_devs);
455 	if (error != 0)
456 		return (error);
457 
458 	iichid = device_get_parent(device_get_parent(dev));
459 	if (device_get_devclass(iichid) != devclass_find("iichid"))
460 		return (ENXIO);
461 
462 	sc->dev = dev;
463 
464 	return (ietp_probe(sc));
465 }
466 
467 static int
468 ietp_iic_attach(device_t dev)
469 {
470 	struct ietp_softc *sc = device_get_softc(dev);
471 	uint16_t buf, reg;
472 	uint8_t *buf8;
473 	uint8_t pattern;
474 
475 	buf8 = (uint8_t *)&buf;
476 
477 	if (ietp_iic_read_reg(dev, IETP_UNIQUEID, sizeof(buf), &buf) != 0) {
478 		device_printf(sc->dev, "failed reading product ID\n");
479 		return (EIO);
480 	}
481 	sc->product_id = le16toh(buf);
482 
483 	if (ietp_iic_read_reg(dev, IETP_PATTERN, sizeof(buf), &buf) != 0) {
484 		device_printf(sc->dev, "failed reading pattern\n");
485 		return (EIO);
486 	}
487 	pattern = buf == 0xFFFF ? 0 : buf8[1];
488 	sc->hi_precision = pattern >= 0x02;
489 
490 	reg = pattern >= 0x01 ? IETP_IC_TYPE : IETP_OSM_VERSION;
491 	if (ietp_iic_read_reg(dev, reg, sizeof(buf), &buf) != 0) {
492 		device_printf(sc->dev, "failed reading IC type\n");
493 		return (EIO);
494 	}
495 	sc->ic_type = pattern >= 0x01 ? be16toh(buf) : buf8[1];
496 
497 	if (ietp_iic_read_reg(dev, IETP_NSM_VERSION, sizeof(buf), &buf) != 0) {
498 		device_printf(sc->dev, "failed reading SM version\n");
499 		return (EIO);
500 	}
501 	sc->is_clickpad = (buf8[0] & 0x10) != 0;
502 
503 	if (ietp_iic_set_absolute_mode(dev, true) != 0) {
504 		device_printf(sc->dev, "failed to set absolute mode\n");
505 		return (EIO);
506 	}
507 
508 	if (ietp_iic_read_reg(dev, IETP_MAX_X_AXIS, sizeof(buf), &buf) != 0) {
509 		device_printf(sc->dev, "failed reading max x\n");
510 		return (EIO);
511 	}
512 	sc->max_x = le16toh(buf);
513 
514 	if (ietp_iic_read_reg(dev, IETP_MAX_Y_AXIS, sizeof(buf), &buf) != 0) {
515 		device_printf(sc->dev, "failed reading max y\n");
516 		return (EIO);
517 	}
518 	sc->max_y = le16toh(buf);
519 
520 	if (ietp_iic_read_reg(dev, IETP_TRACENUM, sizeof(buf), &buf) != 0) {
521 		device_printf(sc->dev, "failed reading trace info\n");
522 		return (EIO);
523 	}
524 	sc->trace_x = sc->max_x / buf8[0];
525 	sc->trace_y = sc->max_y / buf8[1];
526 
527 	if (ietp_iic_read_reg(dev, IETP_PRESSURE, sizeof(buf), &buf) != 0) {
528 		device_printf(sc->dev, "failed reading pressure format\n");
529 		return (EIO);
530 	}
531 	sc->pressure_base = (buf8[0] & 0x10) ? 0 : IETP_PRESSURE_BASE;
532 
533 	if (ietp_iic_read_reg(dev, IETP_RESOLUTION, sizeof(buf), &buf)  != 0) {
534 		device_printf(sc->dev, "failed reading resolution\n");
535 		return (EIO);
536 	}
537 	/* Conversion from internal format to dot per mm */
538 	sc->res_x = ietp_res2dpmm(buf8[0], sc->hi_precision);
539 	sc->res_y = ietp_res2dpmm(buf8[1], sc->hi_precision);
540 
541 	return (ietp_attach(sc));
542 }
543 
544 static int
545 ietp_iic_detach(device_t dev)
546 {
547 	struct ietp_softc *sc = device_get_softc(dev);
548 
549 	if (ietp_iic_set_absolute_mode(dev, false) != 0)
550 		device_printf(dev, "failed setting standard mode\n");
551 
552 	return (ietp_detach(sc));
553 }
554 
555 static int
556 ietp_iic_resume(device_t dev)
557 {
558 	if (ietp_iic_set_absolute_mode(dev, true) != 0) {
559 		device_printf(dev, "reset when resuming failed: \n");
560 		return (EIO);
561 	}
562 
563 	return (0);
564 }
565 
566 static int
567 ietp_iic_set_absolute_mode(device_t dev, bool enable)
568 {
569 	struct ietp_softc *sc = device_get_softc(dev);
570 	static const struct {
571 		uint16_t	ic_type;
572 		uint16_t	product_id;
573 	} special_fw[] = {
574 	    { 0x0E, 0x05 }, { 0x0E, 0x06 }, { 0x0E, 0x07 }, { 0x0E, 0x09 },
575 	    { 0x0E, 0x13 }, { 0x08, 0x26 },
576 	};
577 	uint16_t val;
578 	int i, error;
579 	bool require_wakeup;
580 
581 	error = 0;
582 
583 	/*
584 	 * Some ASUS touchpads need to be powered on to enter absolute mode.
585 	 */
586 	require_wakeup = false;
587 	for (i = 0; i < nitems(special_fw); i++) {
588 		if (sc->ic_type == special_fw[i].ic_type &&
589 		    sc->product_id == special_fw[i].product_id) {
590 			require_wakeup = true;
591 			break;
592 		}
593 	}
594 
595 	if (require_wakeup && hid_intr_start(dev) != 0) {
596 		device_printf(dev, "failed writing poweron command\n");
597 		return (EIO);
598 	}
599 
600 	val = enable ? IETP_CTRL_ABSOLUTE : IETP_CTRL_STANDARD;
601 	if (ietp_iic_write_reg(dev, IETP_CONTROL, val) != 0) {
602 		device_printf(dev, "failed setting absolute mode\n");
603 		error = EIO;
604 	}
605 
606 	if (require_wakeup && hid_intr_stop(dev) != 0) {
607 		device_printf(dev, "failed writing poweroff command\n");
608 		error = EIO;
609 	}
610 
611 	return (error);
612 }
613 
614 static int
615 ietp_iic_read_reg(device_t dev, uint16_t reg, size_t len, void *val)
616 {
617 	device_t iichid = device_get_parent(device_get_parent(dev));
618 	uint16_t addr = iicbus_get_addr(iichid) << 1;
619 	uint8_t cmd[2] = { reg & 0xff, (reg >> 8) & 0xff };
620 	struct iic_msg msgs[2] = {
621 	    { addr, IIC_M_WR | IIC_M_NOSTOP,  sizeof(cmd), cmd },
622 	    { addr, IIC_M_RD, len, val },
623 	};
624 	struct iic_rdwr_data ird = { msgs, nitems(msgs) };
625 	int error;
626 
627 	DPRINTF("Read reg 0x%04x with size %zu\n", reg, len);
628 
629 	error = hid_ioctl(dev, I2CRDWR, (uintptr_t)&ird);
630 	if (error != 0)
631 		return (error);
632 
633 	DPRINTF("Response: %*D\n", (int)len, val, " ");
634 
635 	return (0);
636 }
637 
638 static int
639 ietp_iic_write_reg(device_t dev, uint16_t reg, uint16_t val)
640 {
641 	device_t iichid = device_get_parent(device_get_parent(dev));
642 	uint16_t addr = iicbus_get_addr(iichid) << 1;
643 	uint8_t cmd[4] = { reg & 0xff, (reg >> 8) & 0xff,
644 			   val & 0xff, (val >> 8) & 0xff };
645 	struct iic_msg msgs[1] = {
646 	    { addr, IIC_M_WR, sizeof(cmd), cmd },
647 	};
648 	struct iic_rdwr_data ird = { msgs, nitems(msgs) };
649 
650 	DPRINTF("Write reg 0x%04x with value 0x%04x\n", reg, val);
651 
652 	return (hid_ioctl(dev, I2CRDWR, (uintptr_t)&ird));
653 }
654 
655 static device_method_t ietp_methods[] = {
656 	DEVMETHOD(device_identify,	ietp_iic_identify),
657 	DEVMETHOD(device_probe,		ietp_iic_probe),
658 	DEVMETHOD(device_attach,	ietp_iic_attach),
659 	DEVMETHOD(device_detach,	ietp_iic_detach),
660 	DEVMETHOD(device_resume,	ietp_iic_resume),
661 	DEVMETHOD_END
662 };
663 
664 static driver_t ietp_driver = {
665 	.name = "ietp",
666 	.methods = ietp_methods,
667 	.size = sizeof(struct ietp_softc),
668 };
669 
670 DRIVER_MODULE(ietp, hidbus, ietp_driver, NULL, NULL);
671 MODULE_DEPEND(ietp, hidbus, 1, 1, 1);
672 MODULE_DEPEND(ietp, hid, 1, 1, 1);
673 MODULE_DEPEND(ietp, evdev, 1, 1, 1);
674 MODULE_VERSION(ietp, 1);
675 HID_PNP_INFO(ietp_iic_devs);
676