xref: /openbmc/linux/drivers/input/mouse/elantech.c (revision f7c35abe)
1 /*
2  * Elantech Touchpad driver (v6)
3  *
4  * Copyright (C) 2007-2009 Arjan Opmeer <arjan@opmeer.net>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation.
9  *
10  * Trademarks are the property of their respective owners.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/dmi.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/input.h>
18 #include <linux/input/mt.h>
19 #include <linux/serio.h>
20 #include <linux/libps2.h>
21 #include <asm/unaligned.h>
22 #include "psmouse.h"
23 #include "elantech.h"
24 
25 #define elantech_debug(fmt, ...)					\
26 	do {								\
27 		if (etd->debug)						\
28 			psmouse_printk(KERN_DEBUG, psmouse,		\
29 					fmt, ##__VA_ARGS__);		\
30 	} while (0)
31 
32 /*
33  * Send a Synaptics style sliced query command
34  */
35 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
36 				unsigned char *param)
37 {
38 	if (psmouse_sliced_command(psmouse, c) ||
39 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
40 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
41 		return -1;
42 	}
43 
44 	return 0;
45 }
46 
47 /*
48  * V3 and later support this fast command
49  */
50 static int elantech_send_cmd(struct psmouse *psmouse, unsigned char c,
51 				unsigned char *param)
52 {
53 	struct ps2dev *ps2dev = &psmouse->ps2dev;
54 
55 	if (ps2_command(ps2dev, NULL, ETP_PS2_CUSTOM_COMMAND) ||
56 	    ps2_command(ps2dev, NULL, c) ||
57 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
58 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
59 		return -1;
60 	}
61 
62 	return 0;
63 }
64 
65 /*
66  * A retrying version of ps2_command
67  */
68 static int elantech_ps2_command(struct psmouse *psmouse,
69 				unsigned char *param, int command)
70 {
71 	struct ps2dev *ps2dev = &psmouse->ps2dev;
72 	struct elantech_data *etd = psmouse->private;
73 	int rc;
74 	int tries = ETP_PS2_COMMAND_TRIES;
75 
76 	do {
77 		rc = ps2_command(ps2dev, param, command);
78 		if (rc == 0)
79 			break;
80 		tries--;
81 		elantech_debug("retrying ps2 command 0x%02x (%d).\n",
82 				command, tries);
83 		msleep(ETP_PS2_COMMAND_DELAY);
84 	} while (tries > 0);
85 
86 	if (rc)
87 		psmouse_err(psmouse, "ps2 command 0x%02x failed.\n", command);
88 
89 	return rc;
90 }
91 
92 /*
93  * Send an Elantech style special command to read a value from a register
94  */
95 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
96 				unsigned char *val)
97 {
98 	struct elantech_data *etd = psmouse->private;
99 	unsigned char param[3];
100 	int rc = 0;
101 
102 	if (reg < 0x07 || reg > 0x26)
103 		return -1;
104 
105 	if (reg > 0x11 && reg < 0x20)
106 		return -1;
107 
108 	switch (etd->hw_version) {
109 	case 1:
110 		if (psmouse_sliced_command(psmouse, ETP_REGISTER_READ) ||
111 		    psmouse_sliced_command(psmouse, reg) ||
112 		    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
113 			rc = -1;
114 		}
115 		break;
116 
117 	case 2:
118 		if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
119 		    elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
120 		    elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
121 		    elantech_ps2_command(psmouse,  NULL, reg) ||
122 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
123 			rc = -1;
124 		}
125 		break;
126 
127 	case 3 ... 4:
128 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
129 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
130 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
131 		    elantech_ps2_command(psmouse, NULL, reg) ||
132 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
133 			rc = -1;
134 		}
135 		break;
136 	}
137 
138 	if (rc)
139 		psmouse_err(psmouse, "failed to read register 0x%02x.\n", reg);
140 	else if (etd->hw_version != 4)
141 		*val = param[0];
142 	else
143 		*val = param[1];
144 
145 	return rc;
146 }
147 
148 /*
149  * Send an Elantech style special command to write a register with a value
150  */
151 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
152 				unsigned char val)
153 {
154 	struct elantech_data *etd = psmouse->private;
155 	int rc = 0;
156 
157 	if (reg < 0x07 || reg > 0x26)
158 		return -1;
159 
160 	if (reg > 0x11 && reg < 0x20)
161 		return -1;
162 
163 	switch (etd->hw_version) {
164 	case 1:
165 		if (psmouse_sliced_command(psmouse, ETP_REGISTER_WRITE) ||
166 		    psmouse_sliced_command(psmouse, reg) ||
167 		    psmouse_sliced_command(psmouse, val) ||
168 		    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
169 			rc = -1;
170 		}
171 		break;
172 
173 	case 2:
174 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
175 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
176 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
177 		    elantech_ps2_command(psmouse, NULL, reg) ||
178 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
179 		    elantech_ps2_command(psmouse, NULL, val) ||
180 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
181 			rc = -1;
182 		}
183 		break;
184 
185 	case 3:
186 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
187 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
188 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
189 		    elantech_ps2_command(psmouse, NULL, reg) ||
190 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
191 		    elantech_ps2_command(psmouse, NULL, val) ||
192 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
193 			rc = -1;
194 		}
195 		break;
196 
197 	case 4:
198 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
199 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
200 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
201 		    elantech_ps2_command(psmouse, NULL, reg) ||
202 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
203 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
204 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
205 		    elantech_ps2_command(psmouse, NULL, val) ||
206 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
207 			rc = -1;
208 		}
209 		break;
210 	}
211 
212 	if (rc)
213 		psmouse_err(psmouse,
214 			    "failed to write register 0x%02x with value 0x%02x.\n",
215 			    reg, val);
216 
217 	return rc;
218 }
219 
220 /*
221  * Dump a complete mouse movement packet to the syslog
222  */
223 static void elantech_packet_dump(struct psmouse *psmouse)
224 {
225 	psmouse_printk(KERN_DEBUG, psmouse, "PS/2 packet [%*ph]\n",
226 		       psmouse->pktsize, psmouse->packet);
227 }
228 
229 /*
230  * Interpret complete data packets and report absolute mode input events for
231  * hardware version 1. (4 byte packets)
232  */
233 static void elantech_report_absolute_v1(struct psmouse *psmouse)
234 {
235 	struct input_dev *dev = psmouse->dev;
236 	struct elantech_data *etd = psmouse->private;
237 	unsigned char *packet = psmouse->packet;
238 	int fingers;
239 
240 	if (etd->fw_version < 0x020000) {
241 		/*
242 		 * byte 0:  D   U  p1  p2   1  p3   R   L
243 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
244 		 */
245 		fingers = ((packet[1] & 0x80) >> 7) +
246 				((packet[1] & 0x30) >> 4);
247 	} else {
248 		/*
249 		 * byte 0: n1  n0  p2  p1   1  p3   R   L
250 		 * byte 1:  0   0   0   0  x9  x8  y9  y8
251 		 */
252 		fingers = (packet[0] & 0xc0) >> 6;
253 	}
254 
255 	if (etd->jumpy_cursor) {
256 		if (fingers != 1) {
257 			etd->single_finger_reports = 0;
258 		} else if (etd->single_finger_reports < 2) {
259 			/* Discard first 2 reports of one finger, bogus */
260 			etd->single_finger_reports++;
261 			elantech_debug("discarding packet\n");
262 			return;
263 		}
264 	}
265 
266 	input_report_key(dev, BTN_TOUCH, fingers != 0);
267 
268 	/*
269 	 * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
270 	 * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
271 	 */
272 	if (fingers) {
273 		input_report_abs(dev, ABS_X,
274 			((packet[1] & 0x0c) << 6) | packet[2]);
275 		input_report_abs(dev, ABS_Y,
276 			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
277 	}
278 
279 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
280 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
281 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
282 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
283 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
284 
285 	if (etd->fw_version < 0x020000 &&
286 	    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
287 		/* rocker up */
288 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
289 		/* rocker down */
290 		input_report_key(dev, BTN_BACK, packet[0] & 0x80);
291 	}
292 
293 	input_sync(dev);
294 }
295 
296 static void elantech_set_slot(struct input_dev *dev, int slot, bool active,
297 			      unsigned int x, unsigned int y)
298 {
299 	input_mt_slot(dev, slot);
300 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
301 	if (active) {
302 		input_report_abs(dev, ABS_MT_POSITION_X, x);
303 		input_report_abs(dev, ABS_MT_POSITION_Y, y);
304 	}
305 }
306 
307 /* x1 < x2 and y1 < y2 when two fingers, x = y = 0 when not pressed */
308 static void elantech_report_semi_mt_data(struct input_dev *dev,
309 					 unsigned int num_fingers,
310 					 unsigned int x1, unsigned int y1,
311 					 unsigned int x2, unsigned int y2)
312 {
313 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
314 	elantech_set_slot(dev, 1, num_fingers >= 2, x2, y2);
315 }
316 
317 /*
318  * Interpret complete data packets and report absolute mode input events for
319  * hardware version 2. (6 byte packets)
320  */
321 static void elantech_report_absolute_v2(struct psmouse *psmouse)
322 {
323 	struct elantech_data *etd = psmouse->private;
324 	struct input_dev *dev = psmouse->dev;
325 	unsigned char *packet = psmouse->packet;
326 	unsigned int fingers, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
327 	unsigned int width = 0, pres = 0;
328 
329 	/* byte 0: n1  n0   .   .   .   .   R   L */
330 	fingers = (packet[0] & 0xc0) >> 6;
331 
332 	switch (fingers) {
333 	case 3:
334 		/*
335 		 * Same as one finger, except report of more than 3 fingers:
336 		 * byte 3:  n4  .   w1  w0   .   .   .   .
337 		 */
338 		if (packet[3] & 0x80)
339 			fingers = 4;
340 		/* pass through... */
341 	case 1:
342 		/*
343 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
344 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
345 		 */
346 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
347 		/*
348 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
349 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
350 		 */
351 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
352 
353 		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
354 		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
355 		break;
356 
357 	case 2:
358 		/*
359 		 * The coordinate of each finger is reported separately
360 		 * with a lower resolution for two finger touches:
361 		 * byte 0:  .   .  ay8 ax8  .   .   .   .
362 		 * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
363 		 */
364 		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
365 		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
366 		y1 = etd->y_max -
367 			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
368 		/*
369 		 * byte 3:  .   .  by8 bx8  .   .   .   .
370 		 * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
371 		 */
372 		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
373 		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
374 		y2 = etd->y_max -
375 			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
376 
377 		/* Unknown so just report sensible values */
378 		pres = 127;
379 		width = 7;
380 		break;
381 	}
382 
383 	input_report_key(dev, BTN_TOUCH, fingers != 0);
384 	if (fingers != 0) {
385 		input_report_abs(dev, ABS_X, x1);
386 		input_report_abs(dev, ABS_Y, y1);
387 	}
388 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
389 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
390 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
391 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
392 	input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);
393 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
394 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
395 	if (etd->reports_pressure) {
396 		input_report_abs(dev, ABS_PRESSURE, pres);
397 		input_report_abs(dev, ABS_TOOL_WIDTH, width);
398 	}
399 
400 	input_sync(dev);
401 }
402 
403 static void elantech_report_trackpoint(struct psmouse *psmouse,
404 				       int packet_type)
405 {
406 	/*
407 	 * byte 0:  0   0  sx  sy   0   M   R   L
408 	 * byte 1:~sx   0   0   0   0   0   0   0
409 	 * byte 2:~sy   0   0   0   0   0   0   0
410 	 * byte 3:  0   0 ~sy ~sx   0   1   1   0
411 	 * byte 4: x7  x6  x5  x4  x3  x2  x1  x0
412 	 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
413 	 *
414 	 * x and y are written in two's complement spread
415 	 * over 9 bits with sx/sy the relative top bit and
416 	 * x7..x0 and y7..y0 the lower bits.
417 	 * The sign of y is opposite to what the input driver
418 	 * expects for a relative movement
419 	 */
420 
421 	struct elantech_data *etd = psmouse->private;
422 	struct input_dev *tp_dev = etd->tp_dev;
423 	unsigned char *packet = psmouse->packet;
424 	int x, y;
425 	u32 t;
426 
427 	t = get_unaligned_le32(&packet[0]);
428 
429 	switch (t & ~7U) {
430 	case 0x06000030U:
431 	case 0x16008020U:
432 	case 0x26800010U:
433 	case 0x36808000U:
434 		x = packet[4] - (int)((packet[1]^0x80) << 1);
435 		y = (int)((packet[2]^0x80) << 1) - packet[5];
436 
437 		input_report_key(tp_dev, BTN_LEFT, packet[0] & 0x01);
438 		input_report_key(tp_dev, BTN_RIGHT, packet[0] & 0x02);
439 		input_report_key(tp_dev, BTN_MIDDLE, packet[0] & 0x04);
440 
441 		input_report_rel(tp_dev, REL_X, x);
442 		input_report_rel(tp_dev, REL_Y, y);
443 
444 		input_sync(tp_dev);
445 
446 		break;
447 
448 	default:
449 		/* Dump unexpected packet sequences if debug=1 (default) */
450 		if (etd->debug == 1)
451 			elantech_packet_dump(psmouse);
452 
453 		break;
454 	}
455 }
456 
457 /*
458  * Interpret complete data packets and report absolute mode input events for
459  * hardware version 3. (12 byte packets for two fingers)
460  */
461 static void elantech_report_absolute_v3(struct psmouse *psmouse,
462 					int packet_type)
463 {
464 	struct input_dev *dev = psmouse->dev;
465 	struct elantech_data *etd = psmouse->private;
466 	unsigned char *packet = psmouse->packet;
467 	unsigned int fingers = 0, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
468 	unsigned int width = 0, pres = 0;
469 
470 	/* byte 0: n1  n0   .   .   .   .   R   L */
471 	fingers = (packet[0] & 0xc0) >> 6;
472 
473 	switch (fingers) {
474 	case 3:
475 	case 1:
476 		/*
477 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
478 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
479 		 */
480 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
481 		/*
482 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
483 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
484 		 */
485 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
486 		break;
487 
488 	case 2:
489 		if (packet_type == PACKET_V3_HEAD) {
490 			/*
491 			 * byte 1:   .    .    .    .  ax11 ax10 ax9  ax8
492 			 * byte 2: ax7  ax6  ax5  ax4  ax3  ax2  ax1  ax0
493 			 */
494 			etd->mt[0].x = ((packet[1] & 0x0f) << 8) | packet[2];
495 			/*
496 			 * byte 4:   .    .    .    .  ay11 ay10 ay9  ay8
497 			 * byte 5: ay7  ay6  ay5  ay4  ay3  ay2  ay1  ay0
498 			 */
499 			etd->mt[0].y = etd->y_max -
500 				(((packet[4] & 0x0f) << 8) | packet[5]);
501 			/*
502 			 * wait for next packet
503 			 */
504 			return;
505 		}
506 
507 		/* packet_type == PACKET_V3_TAIL */
508 		x1 = etd->mt[0].x;
509 		y1 = etd->mt[0].y;
510 		x2 = ((packet[1] & 0x0f) << 8) | packet[2];
511 		y2 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
512 		break;
513 	}
514 
515 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
516 	width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
517 
518 	input_report_key(dev, BTN_TOUCH, fingers != 0);
519 	if (fingers != 0) {
520 		input_report_abs(dev, ABS_X, x1);
521 		input_report_abs(dev, ABS_Y, y1);
522 	}
523 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
524 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
525 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
526 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
527 
528 	/* For clickpads map both buttons to BTN_LEFT */
529 	if (etd->fw_version & 0x001000) {
530 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
531 	} else {
532 		input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
533 		input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
534 	}
535 
536 	input_report_abs(dev, ABS_PRESSURE, pres);
537 	input_report_abs(dev, ABS_TOOL_WIDTH, width);
538 
539 	input_sync(dev);
540 }
541 
542 static void elantech_input_sync_v4(struct psmouse *psmouse)
543 {
544 	struct input_dev *dev = psmouse->dev;
545 	struct elantech_data *etd = psmouse->private;
546 	unsigned char *packet = psmouse->packet;
547 
548 	/* For clickpads map both buttons to BTN_LEFT */
549 	if (etd->fw_version & 0x001000) {
550 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
551 	} else {
552 		input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
553 		input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
554 		input_report_key(dev, BTN_MIDDLE, packet[0] & 0x04);
555 	}
556 
557 	input_mt_report_pointer_emulation(dev, true);
558 	input_sync(dev);
559 }
560 
561 static void process_packet_status_v4(struct psmouse *psmouse)
562 {
563 	struct input_dev *dev = psmouse->dev;
564 	unsigned char *packet = psmouse->packet;
565 	unsigned fingers;
566 	int i;
567 
568 	/* notify finger state change */
569 	fingers = packet[1] & 0x1f;
570 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
571 		if ((fingers & (1 << i)) == 0) {
572 			input_mt_slot(dev, i);
573 			input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
574 		}
575 	}
576 
577 	elantech_input_sync_v4(psmouse);
578 }
579 
580 static void process_packet_head_v4(struct psmouse *psmouse)
581 {
582 	struct input_dev *dev = psmouse->dev;
583 	struct elantech_data *etd = psmouse->private;
584 	unsigned char *packet = psmouse->packet;
585 	int id = ((packet[3] & 0xe0) >> 5) - 1;
586 	int pres, traces;
587 
588 	if (id < 0)
589 		return;
590 
591 	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
592 	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
593 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
594 	traces = (packet[0] & 0xf0) >> 4;
595 
596 	input_mt_slot(dev, id);
597 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
598 
599 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
600 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
601 	input_report_abs(dev, ABS_MT_PRESSURE, pres);
602 	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, traces * etd->width);
603 	/* report this for backwards compatibility */
604 	input_report_abs(dev, ABS_TOOL_WIDTH, traces);
605 
606 	elantech_input_sync_v4(psmouse);
607 }
608 
609 static void process_packet_motion_v4(struct psmouse *psmouse)
610 {
611 	struct input_dev *dev = psmouse->dev;
612 	struct elantech_data *etd = psmouse->private;
613 	unsigned char *packet = psmouse->packet;
614 	int weight, delta_x1 = 0, delta_y1 = 0, delta_x2 = 0, delta_y2 = 0;
615 	int id, sid;
616 
617 	id = ((packet[0] & 0xe0) >> 5) - 1;
618 	if (id < 0)
619 		return;
620 
621 	sid = ((packet[3] & 0xe0) >> 5) - 1;
622 	weight = (packet[0] & 0x10) ? ETP_WEIGHT_VALUE : 1;
623 	/*
624 	 * Motion packets give us the delta of x, y values of specific fingers,
625 	 * but in two's complement. Let the compiler do the conversion for us.
626 	 * Also _enlarge_ the numbers to int, in case of overflow.
627 	 */
628 	delta_x1 = (signed char)packet[1];
629 	delta_y1 = (signed char)packet[2];
630 	delta_x2 = (signed char)packet[4];
631 	delta_y2 = (signed char)packet[5];
632 
633 	etd->mt[id].x += delta_x1 * weight;
634 	etd->mt[id].y -= delta_y1 * weight;
635 	input_mt_slot(dev, id);
636 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
637 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
638 
639 	if (sid >= 0) {
640 		etd->mt[sid].x += delta_x2 * weight;
641 		etd->mt[sid].y -= delta_y2 * weight;
642 		input_mt_slot(dev, sid);
643 		input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[sid].x);
644 		input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[sid].y);
645 	}
646 
647 	elantech_input_sync_v4(psmouse);
648 }
649 
650 static void elantech_report_absolute_v4(struct psmouse *psmouse,
651 					int packet_type)
652 {
653 	switch (packet_type) {
654 	case PACKET_V4_STATUS:
655 		process_packet_status_v4(psmouse);
656 		break;
657 
658 	case PACKET_V4_HEAD:
659 		process_packet_head_v4(psmouse);
660 		break;
661 
662 	case PACKET_V4_MOTION:
663 		process_packet_motion_v4(psmouse);
664 		break;
665 
666 	case PACKET_UNKNOWN:
667 	default:
668 		/* impossible to get here */
669 		break;
670 	}
671 }
672 
673 static int elantech_packet_check_v1(struct psmouse *psmouse)
674 {
675 	struct elantech_data *etd = psmouse->private;
676 	unsigned char *packet = psmouse->packet;
677 	unsigned char p1, p2, p3;
678 
679 	/* Parity bits are placed differently */
680 	if (etd->fw_version < 0x020000) {
681 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
682 		p1 = (packet[0] & 0x20) >> 5;
683 		p2 = (packet[0] & 0x10) >> 4;
684 	} else {
685 		/* byte 0: n1  n0  p2  p1   1  p3   R   L */
686 		p1 = (packet[0] & 0x10) >> 4;
687 		p2 = (packet[0] & 0x20) >> 5;
688 	}
689 
690 	p3 = (packet[0] & 0x04) >> 2;
691 
692 	return etd->parity[packet[1]] == p1 &&
693 	       etd->parity[packet[2]] == p2 &&
694 	       etd->parity[packet[3]] == p3;
695 }
696 
697 static int elantech_debounce_check_v2(struct psmouse *psmouse)
698 {
699         /*
700          * When we encounter packet that matches this exactly, it means the
701          * hardware is in debounce status. Just ignore the whole packet.
702          */
703         const u8 debounce_packet[] = { 0x84, 0xff, 0xff, 0x02, 0xff, 0xff };
704         unsigned char *packet = psmouse->packet;
705 
706         return !memcmp(packet, debounce_packet, sizeof(debounce_packet));
707 }
708 
709 static int elantech_packet_check_v2(struct psmouse *psmouse)
710 {
711 	struct elantech_data *etd = psmouse->private;
712 	unsigned char *packet = psmouse->packet;
713 
714 	/*
715 	 * V2 hardware has two flavors. Older ones that do not report pressure,
716 	 * and newer ones that reports pressure and width. With newer ones, all
717 	 * packets (1, 2, 3 finger touch) have the same constant bits. With
718 	 * older ones, 1/3 finger touch packets and 2 finger touch packets
719 	 * have different constant bits.
720 	 * With all three cases, if the constant bits are not exactly what I
721 	 * expected, I consider them invalid.
722 	 */
723 	if (etd->reports_pressure)
724 		return (packet[0] & 0x0c) == 0x04 &&
725 		       (packet[3] & 0x0f) == 0x02;
726 
727 	if ((packet[0] & 0xc0) == 0x80)
728 		return (packet[0] & 0x0c) == 0x0c &&
729 		       (packet[3] & 0x0e) == 0x08;
730 
731 	return (packet[0] & 0x3c) == 0x3c &&
732 	       (packet[1] & 0xf0) == 0x00 &&
733 	       (packet[3] & 0x3e) == 0x38 &&
734 	       (packet[4] & 0xf0) == 0x00;
735 }
736 
737 /*
738  * We check the constant bits to determine what packet type we get,
739  * so packet checking is mandatory for v3 and later hardware.
740  */
741 static int elantech_packet_check_v3(struct psmouse *psmouse)
742 {
743 	struct elantech_data *etd = psmouse->private;
744 	const u8 debounce_packet[] = { 0xc4, 0xff, 0xff, 0x02, 0xff, 0xff };
745 	unsigned char *packet = psmouse->packet;
746 
747 	/*
748 	 * check debounce first, it has the same signature in byte 0
749 	 * and byte 3 as PACKET_V3_HEAD.
750 	 */
751 	if (!memcmp(packet, debounce_packet, sizeof(debounce_packet)))
752 		return PACKET_DEBOUNCE;
753 
754 	/*
755 	 * If the hardware flag 'crc_enabled' is set the packets have
756 	 * different signatures.
757 	 */
758 	if (etd->crc_enabled) {
759 		if ((packet[3] & 0x09) == 0x08)
760 			return PACKET_V3_HEAD;
761 
762 		if ((packet[3] & 0x09) == 0x09)
763 			return PACKET_V3_TAIL;
764 	} else {
765 		if ((packet[0] & 0x0c) == 0x04 && (packet[3] & 0xcf) == 0x02)
766 			return PACKET_V3_HEAD;
767 
768 		if ((packet[0] & 0x0c) == 0x0c && (packet[3] & 0xce) == 0x0c)
769 			return PACKET_V3_TAIL;
770 		if ((packet[3] & 0x0f) == 0x06)
771 			return PACKET_TRACKPOINT;
772 	}
773 
774 	return PACKET_UNKNOWN;
775 }
776 
777 static int elantech_packet_check_v4(struct psmouse *psmouse)
778 {
779 	struct elantech_data *etd = psmouse->private;
780 	unsigned char *packet = psmouse->packet;
781 	unsigned char packet_type = packet[3] & 0x03;
782 	unsigned int ic_version;
783 	bool sanity_check;
784 
785 	if (etd->tp_dev && (packet[3] & 0x0f) == 0x06)
786 		return PACKET_TRACKPOINT;
787 
788 	/* This represents the version of IC body. */
789 	ic_version = (etd->fw_version & 0x0f0000) >> 16;
790 
791 	/*
792 	 * Sanity check based on the constant bits of a packet.
793 	 * The constant bits change depending on the value of
794 	 * the hardware flag 'crc_enabled' and the version of
795 	 * the IC body, but are the same for every packet,
796 	 * regardless of the type.
797 	 */
798 	if (etd->crc_enabled)
799 		sanity_check = ((packet[3] & 0x08) == 0x00);
800 	else if (ic_version == 7 && etd->samples[1] == 0x2A)
801 		sanity_check = ((packet[3] & 0x1c) == 0x10);
802 	else
803 		sanity_check = ((packet[0] & 0x0c) == 0x04 &&
804 				(packet[3] & 0x1c) == 0x10);
805 
806 	if (!sanity_check)
807 		return PACKET_UNKNOWN;
808 
809 	switch (packet_type) {
810 	case 0:
811 		return PACKET_V4_STATUS;
812 
813 	case 1:
814 		return PACKET_V4_HEAD;
815 
816 	case 2:
817 		return PACKET_V4_MOTION;
818 	}
819 
820 	return PACKET_UNKNOWN;
821 }
822 
823 /*
824  * Process byte stream from mouse and handle complete packets
825  */
826 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
827 {
828 	struct elantech_data *etd = psmouse->private;
829 	int packet_type;
830 
831 	if (psmouse->pktcnt < psmouse->pktsize)
832 		return PSMOUSE_GOOD_DATA;
833 
834 	if (etd->debug > 1)
835 		elantech_packet_dump(psmouse);
836 
837 	switch (etd->hw_version) {
838 	case 1:
839 		if (etd->paritycheck && !elantech_packet_check_v1(psmouse))
840 			return PSMOUSE_BAD_DATA;
841 
842 		elantech_report_absolute_v1(psmouse);
843 		break;
844 
845 	case 2:
846 		/* ignore debounce */
847 		if (elantech_debounce_check_v2(psmouse))
848 			return PSMOUSE_FULL_PACKET;
849 
850 		if (etd->paritycheck && !elantech_packet_check_v2(psmouse))
851 			return PSMOUSE_BAD_DATA;
852 
853 		elantech_report_absolute_v2(psmouse);
854 		break;
855 
856 	case 3:
857 		packet_type = elantech_packet_check_v3(psmouse);
858 		switch (packet_type) {
859 		case PACKET_UNKNOWN:
860 			return PSMOUSE_BAD_DATA;
861 
862 		case PACKET_DEBOUNCE:
863 			/* ignore debounce */
864 			break;
865 
866 		case PACKET_TRACKPOINT:
867 			elantech_report_trackpoint(psmouse, packet_type);
868 			break;
869 
870 		default:
871 			elantech_report_absolute_v3(psmouse, packet_type);
872 			break;
873 		}
874 
875 		break;
876 
877 	case 4:
878 		packet_type = elantech_packet_check_v4(psmouse);
879 		switch (packet_type) {
880 		case PACKET_UNKNOWN:
881 			return PSMOUSE_BAD_DATA;
882 
883 		case PACKET_TRACKPOINT:
884 			elantech_report_trackpoint(psmouse, packet_type);
885 			break;
886 
887 		default:
888 			elantech_report_absolute_v4(psmouse, packet_type);
889 			break;
890 		}
891 
892 		break;
893 	}
894 
895 	return PSMOUSE_FULL_PACKET;
896 }
897 
898 /*
899  * This writes the reg_07 value again to the hardware at the end of every
900  * set_rate call because the register loses its value. reg_07 allows setting
901  * absolute mode on v4 hardware
902  */
903 static void elantech_set_rate_restore_reg_07(struct psmouse *psmouse,
904 		unsigned int rate)
905 {
906 	struct elantech_data *etd = psmouse->private;
907 
908 	etd->original_set_rate(psmouse, rate);
909 	if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
910 		psmouse_err(psmouse, "restoring reg_07 failed\n");
911 }
912 
913 /*
914  * Put the touchpad into absolute mode
915  */
916 static int elantech_set_absolute_mode(struct psmouse *psmouse)
917 {
918 	struct elantech_data *etd = psmouse->private;
919 	unsigned char val;
920 	int tries = ETP_READ_BACK_TRIES;
921 	int rc = 0;
922 
923 	switch (etd->hw_version) {
924 	case 1:
925 		etd->reg_10 = 0x16;
926 		etd->reg_11 = 0x8f;
927 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
928 		    elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
929 			rc = -1;
930 		}
931 		break;
932 
933 	case 2:
934 					/* Windows driver values */
935 		etd->reg_10 = 0x54;
936 		etd->reg_11 = 0x88;	/* 0x8a */
937 		etd->reg_21 = 0x60;	/* 0x00 */
938 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
939 		    elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
940 		    elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
941 			rc = -1;
942 		}
943 		break;
944 
945 	case 3:
946 		if (etd->set_hw_resolution)
947 			etd->reg_10 = 0x0b;
948 		else
949 			etd->reg_10 = 0x01;
950 
951 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10))
952 			rc = -1;
953 
954 		break;
955 
956 	case 4:
957 		etd->reg_07 = 0x01;
958 		if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
959 			rc = -1;
960 
961 		goto skip_readback_reg_10; /* v4 has no reg 0x10 to read */
962 	}
963 
964 	if (rc == 0) {
965 		/*
966 		 * Read back reg 0x10. For hardware version 1 we must make
967 		 * sure the absolute mode bit is set. For hardware version 2
968 		 * the touchpad is probably initializing and not ready until
969 		 * we read back the value we just wrote.
970 		 */
971 		do {
972 			rc = elantech_read_reg(psmouse, 0x10, &val);
973 			if (rc == 0)
974 				break;
975 			tries--;
976 			elantech_debug("retrying read (%d).\n", tries);
977 			msleep(ETP_READ_BACK_DELAY);
978 		} while (tries > 0);
979 
980 		if (rc) {
981 			psmouse_err(psmouse,
982 				    "failed to read back register 0x10.\n");
983 		} else if (etd->hw_version == 1 &&
984 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
985 			psmouse_err(psmouse,
986 				    "touchpad refuses to switch to absolute mode.\n");
987 			rc = -1;
988 		}
989 	}
990 
991  skip_readback_reg_10:
992 	if (rc)
993 		psmouse_err(psmouse, "failed to initialise registers.\n");
994 
995 	return rc;
996 }
997 
998 static int elantech_set_range(struct psmouse *psmouse,
999 			      unsigned int *x_min, unsigned int *y_min,
1000 			      unsigned int *x_max, unsigned int *y_max,
1001 			      unsigned int *width)
1002 {
1003 	struct elantech_data *etd = psmouse->private;
1004 	unsigned char param[3];
1005 	unsigned char traces;
1006 
1007 	switch (etd->hw_version) {
1008 	case 1:
1009 		*x_min = ETP_XMIN_V1;
1010 		*y_min = ETP_YMIN_V1;
1011 		*x_max = ETP_XMAX_V1;
1012 		*y_max = ETP_YMAX_V1;
1013 		break;
1014 
1015 	case 2:
1016 		if (etd->fw_version == 0x020800 ||
1017 		    etd->fw_version == 0x020b00 ||
1018 		    etd->fw_version == 0x020030) {
1019 			*x_min = ETP_XMIN_V2;
1020 			*y_min = ETP_YMIN_V2;
1021 			*x_max = ETP_XMAX_V2;
1022 			*y_max = ETP_YMAX_V2;
1023 		} else {
1024 			int i;
1025 			int fixed_dpi;
1026 
1027 			i = (etd->fw_version > 0x020800 &&
1028 			     etd->fw_version < 0x020900) ? 1 : 2;
1029 
1030 			if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1031 				return -1;
1032 
1033 			fixed_dpi = param[1] & 0x10;
1034 
1035 			if (((etd->fw_version >> 16) == 0x14) && fixed_dpi) {
1036 				if (etd->send_cmd(psmouse, ETP_SAMPLE_QUERY, param))
1037 					return -1;
1038 
1039 				*x_max = (etd->capabilities[1] - i) * param[1] / 2;
1040 				*y_max = (etd->capabilities[2] - i) * param[2] / 2;
1041 			} else if (etd->fw_version == 0x040216) {
1042 				*x_max = 819;
1043 				*y_max = 405;
1044 			} else if (etd->fw_version == 0x040219 || etd->fw_version == 0x040215) {
1045 				*x_max = 900;
1046 				*y_max = 500;
1047 			} else {
1048 				*x_max = (etd->capabilities[1] - i) * 64;
1049 				*y_max = (etd->capabilities[2] - i) * 64;
1050 			}
1051 		}
1052 		break;
1053 
1054 	case 3:
1055 		if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1056 			return -1;
1057 
1058 		*x_max = (0x0f & param[0]) << 8 | param[1];
1059 		*y_max = (0xf0 & param[0]) << 4 | param[2];
1060 		break;
1061 
1062 	case 4:
1063 		if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1064 			return -1;
1065 
1066 		*x_max = (0x0f & param[0]) << 8 | param[1];
1067 		*y_max = (0xf0 & param[0]) << 4 | param[2];
1068 		traces = etd->capabilities[1];
1069 		if ((traces < 2) || (traces > *x_max))
1070 			return -1;
1071 
1072 		*width = *x_max / (traces - 1);
1073 		break;
1074 	}
1075 
1076 	return 0;
1077 }
1078 
1079 /*
1080  * (value from firmware) * 10 + 790 = dpi
1081  * we also have to convert dpi to dots/mm (*10/254 to avoid floating point)
1082  */
1083 static unsigned int elantech_convert_res(unsigned int val)
1084 {
1085 	return (val * 10 + 790) * 10 / 254;
1086 }
1087 
1088 static int elantech_get_resolution_v4(struct psmouse *psmouse,
1089 				      unsigned int *x_res,
1090 				      unsigned int *y_res)
1091 {
1092 	unsigned char param[3];
1093 
1094 	if (elantech_send_cmd(psmouse, ETP_RESOLUTION_QUERY, param))
1095 		return -1;
1096 
1097 	*x_res = elantech_convert_res(param[1] & 0x0f);
1098 	*y_res = elantech_convert_res((param[1] & 0xf0) >> 4);
1099 
1100 	return 0;
1101 }
1102 
1103 /*
1104  * Advertise INPUT_PROP_BUTTONPAD for clickpads. The testing of bit 12 in
1105  * fw_version for this is based on the following fw_version & caps table:
1106  *
1107  * Laptop-model:           fw_version:     caps:           buttons:
1108  * Acer S3                 0x461f00        10, 13, 0e      clickpad
1109  * Acer S7-392             0x581f01        50, 17, 0d      clickpad
1110  * Acer V5-131             0x461f02        01, 16, 0c      clickpad
1111  * Acer V5-551             0x461f00        ?               clickpad
1112  * Asus K53SV              0x450f01        78, 15, 0c      2 hw buttons
1113  * Asus G46VW              0x460f02        00, 18, 0c      2 hw buttons
1114  * Asus G750JX             0x360f00        00, 16, 0c      2 hw buttons
1115  * Asus TP500LN            0x381f17        10, 14, 0e      clickpad
1116  * Asus X750JN             0x381f17        10, 14, 0e      clickpad
1117  * Asus UX31               0x361f00        20, 15, 0e      clickpad
1118  * Asus UX32VD             0x361f02        00, 15, 0e      clickpad
1119  * Avatar AVIU-145A2       0x361f00        ?               clickpad
1120  * Fujitsu LIFEBOOK E544   0x470f00        d0, 12, 09      2 hw buttons
1121  * Fujitsu LIFEBOOK E554   0x570f01        40, 14, 0c      2 hw buttons
1122  * Fujitsu T725            0x470f01        05, 12, 09      2 hw buttons
1123  * Fujitsu H730            0x570f00        c0, 14, 0c      3 hw buttons (**)
1124  * Gigabyte U2442          0x450f01        58, 17, 0c      2 hw buttons
1125  * Lenovo L430             0x350f02        b9, 15, 0c      2 hw buttons (*)
1126  * Lenovo L530             0x350f02        b9, 15, 0c      2 hw buttons (*)
1127  * Samsung NF210           0x150b00        78, 14, 0a      2 hw buttons
1128  * Samsung NP770Z5E        0x575f01        10, 15, 0f      clickpad
1129  * Samsung NP700Z5B        0x361f06        21, 15, 0f      clickpad
1130  * Samsung NP900X3E-A02    0x575f03        ?               clickpad
1131  * Samsung NP-QX410        0x851b00        19, 14, 0c      clickpad
1132  * Samsung RC512           0x450f00        08, 15, 0c      2 hw buttons
1133  * Samsung RF710           0x450f00        ?               2 hw buttons
1134  * System76 Pangolin       0x250f01        ?               2 hw buttons
1135  * (*) + 3 trackpoint buttons
1136  * (**) + 0 trackpoint buttons
1137  * Note: Lenovo L430 and Lenovo L530 have the same fw_version/caps
1138  */
1139 static void elantech_set_buttonpad_prop(struct psmouse *psmouse)
1140 {
1141 	struct input_dev *dev = psmouse->dev;
1142 	struct elantech_data *etd = psmouse->private;
1143 
1144 	if (etd->fw_version & 0x001000) {
1145 		__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
1146 		__clear_bit(BTN_RIGHT, dev->keybit);
1147 	}
1148 }
1149 
1150 /*
1151  * Some hw_version 4 models do have a middle button
1152  */
1153 static const struct dmi_system_id elantech_dmi_has_middle_button[] = {
1154 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1155 	{
1156 		/* Fujitsu H730 has a middle button */
1157 		.matches = {
1158 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1159 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1160 		},
1161 	},
1162 	{
1163 		/* Fujitsu H760 also has a middle button */
1164 		.matches = {
1165 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1166 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1167 		},
1168 	},
1169 #endif
1170 	{ }
1171 };
1172 
1173 /*
1174  * Set the appropriate event bits for the input subsystem
1175  */
1176 static int elantech_set_input_params(struct psmouse *psmouse)
1177 {
1178 	struct input_dev *dev = psmouse->dev;
1179 	struct elantech_data *etd = psmouse->private;
1180 	unsigned int x_min = 0, y_min = 0, x_max = 0, y_max = 0, width = 0;
1181 	unsigned int x_res = 31, y_res = 31;
1182 
1183 	if (elantech_set_range(psmouse, &x_min, &y_min, &x_max, &y_max, &width))
1184 		return -1;
1185 
1186 	__set_bit(INPUT_PROP_POINTER, dev->propbit);
1187 	__set_bit(EV_KEY, dev->evbit);
1188 	__set_bit(EV_ABS, dev->evbit);
1189 	__clear_bit(EV_REL, dev->evbit);
1190 
1191 	__set_bit(BTN_LEFT, dev->keybit);
1192 	if (dmi_check_system(elantech_dmi_has_middle_button))
1193 		__set_bit(BTN_MIDDLE, dev->keybit);
1194 	__set_bit(BTN_RIGHT, dev->keybit);
1195 
1196 	__set_bit(BTN_TOUCH, dev->keybit);
1197 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
1198 	__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
1199 	__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
1200 
1201 	switch (etd->hw_version) {
1202 	case 1:
1203 		/* Rocker button */
1204 		if (etd->fw_version < 0x020000 &&
1205 		    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
1206 			__set_bit(BTN_FORWARD, dev->keybit);
1207 			__set_bit(BTN_BACK, dev->keybit);
1208 		}
1209 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1210 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1211 		break;
1212 
1213 	case 2:
1214 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1215 		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
1216 		/* fall through */
1217 	case 3:
1218 		if (etd->hw_version == 3)
1219 			elantech_set_buttonpad_prop(psmouse);
1220 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1221 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1222 		if (etd->reports_pressure) {
1223 			input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1224 					     ETP_PMAX_V2, 0, 0);
1225 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1226 					     ETP_WMAX_V2, 0, 0);
1227 		}
1228 		input_mt_init_slots(dev, 2, INPUT_MT_SEMI_MT);
1229 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1230 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1231 		break;
1232 
1233 	case 4:
1234 		if (elantech_get_resolution_v4(psmouse, &x_res, &y_res)) {
1235 			/*
1236 			 * if query failed, print a warning and leave the values
1237 			 * zero to resemble synaptics.c behavior.
1238 			 */
1239 			psmouse_warn(psmouse, "couldn't query resolution data.\n");
1240 		}
1241 		elantech_set_buttonpad_prop(psmouse);
1242 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1243 		/* For X to recognize me as touchpad. */
1244 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1245 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1246 		/*
1247 		 * range of pressure and width is the same as v2,
1248 		 * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
1249 		 */
1250 		input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1251 				     ETP_PMAX_V2, 0, 0);
1252 		input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1253 				     ETP_WMAX_V2, 0, 0);
1254 		/* Multitouch capable pad, up to 5 fingers. */
1255 		input_mt_init_slots(dev, ETP_MAX_FINGERS, 0);
1256 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1257 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1258 		input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
1259 				     ETP_PMAX_V2, 0, 0);
1260 		/*
1261 		 * The firmware reports how many trace lines the finger spans,
1262 		 * convert to surface unit as Protocol-B requires.
1263 		 */
1264 		input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 0,
1265 				     ETP_WMAX_V2 * width, 0, 0);
1266 		break;
1267 	}
1268 
1269 	input_abs_set_res(dev, ABS_X, x_res);
1270 	input_abs_set_res(dev, ABS_Y, y_res);
1271 	if (etd->hw_version > 1) {
1272 		input_abs_set_res(dev, ABS_MT_POSITION_X, x_res);
1273 		input_abs_set_res(dev, ABS_MT_POSITION_Y, y_res);
1274 	}
1275 
1276 	etd->y_max = y_max;
1277 	etd->width = width;
1278 
1279 	return 0;
1280 }
1281 
1282 struct elantech_attr_data {
1283 	size_t		field_offset;
1284 	unsigned char	reg;
1285 };
1286 
1287 /*
1288  * Display a register value by reading a sysfs entry
1289  */
1290 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
1291 					char *buf)
1292 {
1293 	struct elantech_data *etd = psmouse->private;
1294 	struct elantech_attr_data *attr = data;
1295 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1296 	int rc = 0;
1297 
1298 	if (attr->reg)
1299 		rc = elantech_read_reg(psmouse, attr->reg, reg);
1300 
1301 	return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
1302 }
1303 
1304 /*
1305  * Write a register value by writing a sysfs entry
1306  */
1307 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
1308 				     void *data, const char *buf, size_t count)
1309 {
1310 	struct elantech_data *etd = psmouse->private;
1311 	struct elantech_attr_data *attr = data;
1312 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1313 	unsigned char value;
1314 	int err;
1315 
1316 	err = kstrtou8(buf, 16, &value);
1317 	if (err)
1318 		return err;
1319 
1320 	/* Do we need to preserve some bits for version 2 hardware too? */
1321 	if (etd->hw_version == 1) {
1322 		if (attr->reg == 0x10)
1323 			/* Force absolute mode always on */
1324 			value |= ETP_R10_ABSOLUTE_MODE;
1325 		else if (attr->reg == 0x11)
1326 			/* Force 4 byte mode always on */
1327 			value |= ETP_R11_4_BYTE_MODE;
1328 	}
1329 
1330 	if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
1331 		*reg = value;
1332 
1333 	return count;
1334 }
1335 
1336 #define ELANTECH_INT_ATTR(_name, _register)				\
1337 	static struct elantech_attr_data elantech_attr_##_name = {	\
1338 		.field_offset = offsetof(struct elantech_data, _name),	\
1339 		.reg = _register,					\
1340 	};								\
1341 	PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,			\
1342 			    &elantech_attr_##_name,			\
1343 			    elantech_show_int_attr,			\
1344 			    elantech_set_int_attr)
1345 
1346 ELANTECH_INT_ATTR(reg_07, 0x07);
1347 ELANTECH_INT_ATTR(reg_10, 0x10);
1348 ELANTECH_INT_ATTR(reg_11, 0x11);
1349 ELANTECH_INT_ATTR(reg_20, 0x20);
1350 ELANTECH_INT_ATTR(reg_21, 0x21);
1351 ELANTECH_INT_ATTR(reg_22, 0x22);
1352 ELANTECH_INT_ATTR(reg_23, 0x23);
1353 ELANTECH_INT_ATTR(reg_24, 0x24);
1354 ELANTECH_INT_ATTR(reg_25, 0x25);
1355 ELANTECH_INT_ATTR(reg_26, 0x26);
1356 ELANTECH_INT_ATTR(debug, 0);
1357 ELANTECH_INT_ATTR(paritycheck, 0);
1358 ELANTECH_INT_ATTR(crc_enabled, 0);
1359 
1360 static struct attribute *elantech_attrs[] = {
1361 	&psmouse_attr_reg_07.dattr.attr,
1362 	&psmouse_attr_reg_10.dattr.attr,
1363 	&psmouse_attr_reg_11.dattr.attr,
1364 	&psmouse_attr_reg_20.dattr.attr,
1365 	&psmouse_attr_reg_21.dattr.attr,
1366 	&psmouse_attr_reg_22.dattr.attr,
1367 	&psmouse_attr_reg_23.dattr.attr,
1368 	&psmouse_attr_reg_24.dattr.attr,
1369 	&psmouse_attr_reg_25.dattr.attr,
1370 	&psmouse_attr_reg_26.dattr.attr,
1371 	&psmouse_attr_debug.dattr.attr,
1372 	&psmouse_attr_paritycheck.dattr.attr,
1373 	&psmouse_attr_crc_enabled.dattr.attr,
1374 	NULL
1375 };
1376 
1377 static struct attribute_group elantech_attr_group = {
1378 	.attrs = elantech_attrs,
1379 };
1380 
1381 static bool elantech_is_signature_valid(const unsigned char *param)
1382 {
1383 	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
1384 	int i;
1385 
1386 	if (param[0] == 0)
1387 		return false;
1388 
1389 	if (param[1] == 0)
1390 		return true;
1391 
1392 	/*
1393 	 * Some hw_version >= 4 models have a revision higher then 20. Meaning
1394 	 * that param[2] may be 10 or 20, skip the rates check for these.
1395 	 */
1396 	if ((param[0] & 0x0f) >= 0x06 && (param[1] & 0xaf) == 0x0f &&
1397 	    param[2] < 40)
1398 		return true;
1399 
1400 	for (i = 0; i < ARRAY_SIZE(rates); i++)
1401 		if (param[2] == rates[i])
1402 			return false;
1403 
1404 	return true;
1405 }
1406 
1407 /*
1408  * Use magic knock to detect Elantech touchpad
1409  */
1410 int elantech_detect(struct psmouse *psmouse, bool set_properties)
1411 {
1412 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1413 	unsigned char param[3];
1414 
1415 	ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1416 
1417 	if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
1418 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1419 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1420 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1421 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1422 		psmouse_dbg(psmouse, "sending Elantech magic knock failed.\n");
1423 		return -1;
1424 	}
1425 
1426 	/*
1427 	 * Report this in case there are Elantech models that use a different
1428 	 * set of magic numbers
1429 	 */
1430 	if (param[0] != 0x3c || param[1] != 0x03 ||
1431 	    (param[2] != 0xc8 && param[2] != 0x00)) {
1432 		psmouse_dbg(psmouse,
1433 			    "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
1434 			    param[0], param[1], param[2]);
1435 		return -1;
1436 	}
1437 
1438 	/*
1439 	 * Query touchpad's firmware version and see if it reports known
1440 	 * value to avoid mis-detection. Logitech mice are known to respond
1441 	 * to Elantech magic knock and there might be more.
1442 	 */
1443 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1444 		psmouse_dbg(psmouse, "failed to query firmware version.\n");
1445 		return -1;
1446 	}
1447 
1448 	psmouse_dbg(psmouse,
1449 		    "Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
1450 		    param[0], param[1], param[2]);
1451 
1452 	if (!elantech_is_signature_valid(param)) {
1453 		psmouse_dbg(psmouse,
1454 			    "Probably not a real Elantech touchpad. Aborting.\n");
1455 		return -1;
1456 	}
1457 
1458 	if (set_properties) {
1459 		psmouse->vendor = "Elantech";
1460 		psmouse->name = "Touchpad";
1461 	}
1462 
1463 	return 0;
1464 }
1465 
1466 /*
1467  * Clean up sysfs entries when disconnecting
1468  */
1469 static void elantech_disconnect(struct psmouse *psmouse)
1470 {
1471 	struct elantech_data *etd = psmouse->private;
1472 
1473 	if (etd->tp_dev)
1474 		input_unregister_device(etd->tp_dev);
1475 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1476 			   &elantech_attr_group);
1477 	kfree(psmouse->private);
1478 	psmouse->private = NULL;
1479 }
1480 
1481 /*
1482  * Put the touchpad back into absolute mode when reconnecting
1483  */
1484 static int elantech_reconnect(struct psmouse *psmouse)
1485 {
1486 	psmouse_reset(psmouse);
1487 
1488 	if (elantech_detect(psmouse, 0))
1489 		return -1;
1490 
1491 	if (elantech_set_absolute_mode(psmouse)) {
1492 		psmouse_err(psmouse,
1493 			    "failed to put touchpad back into absolute mode.\n");
1494 		return -1;
1495 	}
1496 
1497 	return 0;
1498 }
1499 
1500 /*
1501  * Some hw_version 4 models do not work with crc_disabled
1502  */
1503 static const struct dmi_system_id elantech_dmi_force_crc_enabled[] = {
1504 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1505 	{
1506 		/* Fujitsu H730 does not work with crc_enabled == 0 */
1507 		.matches = {
1508 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1509 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1510 		},
1511 	},
1512 	{
1513 		/* Fujitsu H760 does not work with crc_enabled == 0 */
1514 		.matches = {
1515 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1516 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1517 		},
1518 	},
1519 	{
1520 		/* Fujitsu LIFEBOOK E544  does not work with crc_enabled == 0 */
1521 		.matches = {
1522 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1523 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E544"),
1524 		},
1525 	},
1526 	{
1527 		/* Fujitsu LIFEBOOK E554  does not work with crc_enabled == 0 */
1528 		.matches = {
1529 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1530 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E554"),
1531 		},
1532 	},
1533 	{
1534 		/* Fujitsu LIFEBOOK E556 does not work with crc_enabled == 0 */
1535 		.matches = {
1536 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1537 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E556"),
1538 		},
1539 	},
1540 	{
1541 		/* Fujitsu LIFEBOOK U745 does not work with crc_enabled == 0 */
1542 		.matches = {
1543 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1544 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK U745"),
1545 		},
1546 	},
1547 #endif
1548 	{ }
1549 };
1550 
1551 /*
1552  * Some hw_version 3 models go into error state when we try to set
1553  * bit 3 and/or bit 1 of r10.
1554  */
1555 static const struct dmi_system_id no_hw_res_dmi_table[] = {
1556 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1557 	{
1558 		/* Gigabyte U2442 */
1559 		.matches = {
1560 			DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
1561 			DMI_MATCH(DMI_PRODUCT_NAME, "U2442"),
1562 		},
1563 	},
1564 #endif
1565 	{ }
1566 };
1567 
1568 /*
1569  * determine hardware version and set some properties according to it.
1570  */
1571 static int elantech_set_properties(struct elantech_data *etd)
1572 {
1573 	/* This represents the version of IC body. */
1574 	int ver = (etd->fw_version & 0x0f0000) >> 16;
1575 
1576 	/* Early version of Elan touchpads doesn't obey the rule. */
1577 	if (etd->fw_version < 0x020030 || etd->fw_version == 0x020600)
1578 		etd->hw_version = 1;
1579 	else {
1580 		switch (ver) {
1581 		case 2:
1582 		case 4:
1583 			etd->hw_version = 2;
1584 			break;
1585 		case 5:
1586 			etd->hw_version = 3;
1587 			break;
1588 		case 6 ... 14:
1589 			etd->hw_version = 4;
1590 			break;
1591 		default:
1592 			return -1;
1593 		}
1594 	}
1595 
1596 	/* decide which send_cmd we're gonna use early */
1597 	etd->send_cmd = etd->hw_version >= 3 ? elantech_send_cmd :
1598 					       synaptics_send_cmd;
1599 
1600 	/* Turn on packet checking by default */
1601 	etd->paritycheck = 1;
1602 
1603 	/*
1604 	 * This firmware suffers from misreporting coordinates when
1605 	 * a touch action starts causing the mouse cursor or scrolled page
1606 	 * to jump. Enable a workaround.
1607 	 */
1608 	etd->jumpy_cursor =
1609 		(etd->fw_version == 0x020022 || etd->fw_version == 0x020600);
1610 
1611 	if (etd->hw_version > 1) {
1612 		/* For now show extra debug information */
1613 		etd->debug = 1;
1614 
1615 		if (etd->fw_version >= 0x020800)
1616 			etd->reports_pressure = true;
1617 	}
1618 
1619 	/*
1620 	 * The signatures of v3 and v4 packets change depending on the
1621 	 * value of this hardware flag.
1622 	 */
1623 	etd->crc_enabled = (etd->fw_version & 0x4000) == 0x4000 ||
1624 			   dmi_check_system(elantech_dmi_force_crc_enabled);
1625 
1626 	/* Enable real hardware resolution on hw_version 3 ? */
1627 	etd->set_hw_resolution = !dmi_check_system(no_hw_res_dmi_table);
1628 
1629 	return 0;
1630 }
1631 
1632 /*
1633  * Initialize the touchpad and create sysfs entries
1634  */
1635 int elantech_init(struct psmouse *psmouse)
1636 {
1637 	struct elantech_data *etd;
1638 	int i;
1639 	int error = -EINVAL;
1640 	unsigned char param[3];
1641 	struct input_dev *tp_dev;
1642 
1643 	psmouse->private = etd = kzalloc(sizeof(struct elantech_data), GFP_KERNEL);
1644 	if (!etd)
1645 		return -ENOMEM;
1646 
1647 	psmouse_reset(psmouse);
1648 
1649 	etd->parity[0] = 1;
1650 	for (i = 1; i < 256; i++)
1651 		etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
1652 
1653 	/*
1654 	 * Do the version query again so we can store the result
1655 	 */
1656 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1657 		psmouse_err(psmouse, "failed to query firmware version.\n");
1658 		goto init_fail;
1659 	}
1660 	etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
1661 
1662 	if (elantech_set_properties(etd)) {
1663 		psmouse_err(psmouse, "unknown hardware version, aborting...\n");
1664 		goto init_fail;
1665 	}
1666 	psmouse_info(psmouse,
1667 		     "assuming hardware version %d (with firmware version 0x%02x%02x%02x)\n",
1668 		     etd->hw_version, param[0], param[1], param[2]);
1669 
1670 	if (etd->send_cmd(psmouse, ETP_CAPABILITIES_QUERY,
1671 	    etd->capabilities)) {
1672 		psmouse_err(psmouse, "failed to query capabilities.\n");
1673 		goto init_fail;
1674 	}
1675 	psmouse_info(psmouse,
1676 		     "Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
1677 		     etd->capabilities[0], etd->capabilities[1],
1678 		     etd->capabilities[2]);
1679 
1680 	if (etd->hw_version != 1) {
1681 		if (etd->send_cmd(psmouse, ETP_SAMPLE_QUERY, etd->samples)) {
1682 			psmouse_err(psmouse, "failed to query sample data\n");
1683 			goto init_fail;
1684 		}
1685 		psmouse_info(psmouse,
1686 			     "Elan sample query result %02x, %02x, %02x\n",
1687 			     etd->samples[0], etd->samples[1], etd->samples[2]);
1688 	}
1689 
1690 	if (elantech_set_absolute_mode(psmouse)) {
1691 		psmouse_err(psmouse,
1692 			    "failed to put touchpad into absolute mode.\n");
1693 		goto init_fail;
1694 	}
1695 
1696 	if (etd->fw_version == 0x381f17) {
1697 		etd->original_set_rate = psmouse->set_rate;
1698 		psmouse->set_rate = elantech_set_rate_restore_reg_07;
1699 	}
1700 
1701 	if (elantech_set_input_params(psmouse)) {
1702 		psmouse_err(psmouse, "failed to query touchpad range.\n");
1703 		goto init_fail;
1704 	}
1705 
1706 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
1707 				   &elantech_attr_group);
1708 	if (error) {
1709 		psmouse_err(psmouse,
1710 			    "failed to create sysfs attributes, error: %d.\n",
1711 			    error);
1712 		goto init_fail;
1713 	}
1714 
1715 	/* The MSB indicates the presence of the trackpoint */
1716 	if ((etd->capabilities[0] & 0x80) == 0x80) {
1717 		tp_dev = input_allocate_device();
1718 
1719 		if (!tp_dev) {
1720 			error = -ENOMEM;
1721 			goto init_fail_tp_alloc;
1722 		}
1723 
1724 		etd->tp_dev = tp_dev;
1725 		snprintf(etd->tp_phys, sizeof(etd->tp_phys), "%s/input1",
1726 			psmouse->ps2dev.serio->phys);
1727 		tp_dev->phys = etd->tp_phys;
1728 		tp_dev->name = "ETPS/2 Elantech TrackPoint";
1729 		tp_dev->id.bustype = BUS_I8042;
1730 		tp_dev->id.vendor  = 0x0002;
1731 		tp_dev->id.product = PSMOUSE_ELANTECH;
1732 		tp_dev->id.version = 0x0000;
1733 		tp_dev->dev.parent = &psmouse->ps2dev.serio->dev;
1734 		tp_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
1735 		tp_dev->relbit[BIT_WORD(REL_X)] =
1736 			BIT_MASK(REL_X) | BIT_MASK(REL_Y);
1737 		tp_dev->keybit[BIT_WORD(BTN_LEFT)] =
1738 			BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
1739 			BIT_MASK(BTN_RIGHT);
1740 
1741 		__set_bit(INPUT_PROP_POINTER, tp_dev->propbit);
1742 		__set_bit(INPUT_PROP_POINTING_STICK, tp_dev->propbit);
1743 
1744 		error = input_register_device(etd->tp_dev);
1745 		if (error < 0)
1746 			goto init_fail_tp_reg;
1747 	}
1748 
1749 	psmouse->protocol_handler = elantech_process_byte;
1750 	psmouse->disconnect = elantech_disconnect;
1751 	psmouse->reconnect = elantech_reconnect;
1752 	psmouse->pktsize = etd->hw_version > 1 ? 6 : 4;
1753 
1754 	return 0;
1755  init_fail_tp_reg:
1756 	input_free_device(tp_dev);
1757  init_fail_tp_alloc:
1758 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1759 			   &elantech_attr_group);
1760  init_fail:
1761 	psmouse_reset(psmouse);
1762 	kfree(etd);
1763 	return error;
1764 }
1765