xref: /openbmc/linux/drivers/input/mouse/elantech.c (revision 5e29a910)
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 	int	i;
226 
227 	psmouse_printk(KERN_DEBUG, psmouse, "PS/2 packet [");
228 	for (i = 0; i < psmouse->pktsize; i++)
229 		printk("%s0x%02x ", i ? ", " : " ", psmouse->packet[i]);
230 	printk("]\n");
231 }
232 
233 /*
234  * Interpret complete data packets and report absolute mode input events for
235  * hardware version 1. (4 byte packets)
236  */
237 static void elantech_report_absolute_v1(struct psmouse *psmouse)
238 {
239 	struct input_dev *dev = psmouse->dev;
240 	struct elantech_data *etd = psmouse->private;
241 	unsigned char *packet = psmouse->packet;
242 	int fingers;
243 
244 	if (etd->fw_version < 0x020000) {
245 		/*
246 		 * byte 0:  D   U  p1  p2   1  p3   R   L
247 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
248 		 */
249 		fingers = ((packet[1] & 0x80) >> 7) +
250 				((packet[1] & 0x30) >> 4);
251 	} else {
252 		/*
253 		 * byte 0: n1  n0  p2  p1   1  p3   R   L
254 		 * byte 1:  0   0   0   0  x9  x8  y9  y8
255 		 */
256 		fingers = (packet[0] & 0xc0) >> 6;
257 	}
258 
259 	if (etd->jumpy_cursor) {
260 		if (fingers != 1) {
261 			etd->single_finger_reports = 0;
262 		} else if (etd->single_finger_reports < 2) {
263 			/* Discard first 2 reports of one finger, bogus */
264 			etd->single_finger_reports++;
265 			elantech_debug("discarding packet\n");
266 			return;
267 		}
268 	}
269 
270 	input_report_key(dev, BTN_TOUCH, fingers != 0);
271 
272 	/*
273 	 * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
274 	 * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
275 	 */
276 	if (fingers) {
277 		input_report_abs(dev, ABS_X,
278 			((packet[1] & 0x0c) << 6) | packet[2]);
279 		input_report_abs(dev, ABS_Y,
280 			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
281 	}
282 
283 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
284 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
285 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
286 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
287 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
288 
289 	if (etd->fw_version < 0x020000 &&
290 	    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
291 		/* rocker up */
292 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
293 		/* rocker down */
294 		input_report_key(dev, BTN_BACK, packet[0] & 0x80);
295 	}
296 
297 	input_sync(dev);
298 }
299 
300 static void elantech_set_slot(struct input_dev *dev, int slot, bool active,
301 			      unsigned int x, unsigned int y)
302 {
303 	input_mt_slot(dev, slot);
304 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
305 	if (active) {
306 		input_report_abs(dev, ABS_MT_POSITION_X, x);
307 		input_report_abs(dev, ABS_MT_POSITION_Y, y);
308 	}
309 }
310 
311 /* x1 < x2 and y1 < y2 when two fingers, x = y = 0 when not pressed */
312 static void elantech_report_semi_mt_data(struct input_dev *dev,
313 					 unsigned int num_fingers,
314 					 unsigned int x1, unsigned int y1,
315 					 unsigned int x2, unsigned int y2)
316 {
317 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
318 	elantech_set_slot(dev, 1, num_fingers == 2, x2, y2);
319 }
320 
321 /*
322  * Interpret complete data packets and report absolute mode input events for
323  * hardware version 2. (6 byte packets)
324  */
325 static void elantech_report_absolute_v2(struct psmouse *psmouse)
326 {
327 	struct elantech_data *etd = psmouse->private;
328 	struct input_dev *dev = psmouse->dev;
329 	unsigned char *packet = psmouse->packet;
330 	unsigned int fingers, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
331 	unsigned int width = 0, pres = 0;
332 
333 	/* byte 0: n1  n0   .   .   .   .   R   L */
334 	fingers = (packet[0] & 0xc0) >> 6;
335 
336 	switch (fingers) {
337 	case 3:
338 		/*
339 		 * Same as one finger, except report of more than 3 fingers:
340 		 * byte 3:  n4  .   w1  w0   .   .   .   .
341 		 */
342 		if (packet[3] & 0x80)
343 			fingers = 4;
344 		/* pass through... */
345 	case 1:
346 		/*
347 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
348 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
349 		 */
350 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
351 		/*
352 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
353 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
354 		 */
355 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
356 
357 		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
358 		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
359 		break;
360 
361 	case 2:
362 		/*
363 		 * The coordinate of each finger is reported separately
364 		 * with a lower resolution for two finger touches:
365 		 * byte 0:  .   .  ay8 ax8  .   .   .   .
366 		 * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
367 		 */
368 		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
369 		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
370 		y1 = etd->y_max -
371 			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
372 		/*
373 		 * byte 3:  .   .  by8 bx8  .   .   .   .
374 		 * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
375 		 */
376 		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
377 		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
378 		y2 = etd->y_max -
379 			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
380 
381 		/* Unknown so just report sensible values */
382 		pres = 127;
383 		width = 7;
384 		break;
385 	}
386 
387 	input_report_key(dev, BTN_TOUCH, fingers != 0);
388 	if (fingers != 0) {
389 		input_report_abs(dev, ABS_X, x1);
390 		input_report_abs(dev, ABS_Y, y1);
391 	}
392 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
393 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
394 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
395 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
396 	input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);
397 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
398 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
399 	if (etd->reports_pressure) {
400 		input_report_abs(dev, ABS_PRESSURE, pres);
401 		input_report_abs(dev, ABS_TOOL_WIDTH, width);
402 	}
403 
404 	input_sync(dev);
405 }
406 
407 static void elantech_report_trackpoint(struct psmouse *psmouse,
408 				       int packet_type)
409 {
410 	/*
411 	 * byte 0:  0   0  sx  sy   0   M   R   L
412 	 * byte 1:~sx   0   0   0   0   0   0   0
413 	 * byte 2:~sy   0   0   0   0   0   0   0
414 	 * byte 3:  0   0 ~sy ~sx   0   1   1   0
415 	 * byte 4: x7  x6  x5  x4  x3  x2  x1  x0
416 	 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
417 	 *
418 	 * x and y are written in two's complement spread
419 	 * over 9 bits with sx/sy the relative top bit and
420 	 * x7..x0 and y7..y0 the lower bits.
421 	 * The sign of y is opposite to what the input driver
422 	 * expects for a relative movement
423 	 */
424 
425 	struct elantech_data *etd = psmouse->private;
426 	struct input_dev *tp_dev = etd->tp_dev;
427 	unsigned char *packet = psmouse->packet;
428 	int x, y;
429 	u32 t;
430 
431 	t = get_unaligned_le32(&packet[0]);
432 
433 	switch (t & ~7U) {
434 	case 0x06000030U:
435 	case 0x16008020U:
436 	case 0x26800010U:
437 	case 0x36808000U:
438 		x = packet[4] - (int)((packet[1]^0x80) << 1);
439 		y = (int)((packet[2]^0x80) << 1) - packet[5];
440 
441 		input_report_key(tp_dev, BTN_LEFT, packet[0] & 0x01);
442 		input_report_key(tp_dev, BTN_RIGHT, packet[0] & 0x02);
443 		input_report_key(tp_dev, BTN_MIDDLE, packet[0] & 0x04);
444 
445 		input_report_rel(tp_dev, REL_X, x);
446 		input_report_rel(tp_dev, REL_Y, y);
447 
448 		input_sync(tp_dev);
449 
450 		break;
451 
452 	default:
453 		/* Dump unexpected packet sequences if debug=1 (default) */
454 		if (etd->debug == 1)
455 			elantech_packet_dump(psmouse);
456 
457 		break;
458 	}
459 }
460 
461 /*
462  * Interpret complete data packets and report absolute mode input events for
463  * hardware version 3. (12 byte packets for two fingers)
464  */
465 static void elantech_report_absolute_v3(struct psmouse *psmouse,
466 					int packet_type)
467 {
468 	struct input_dev *dev = psmouse->dev;
469 	struct elantech_data *etd = psmouse->private;
470 	unsigned char *packet = psmouse->packet;
471 	unsigned int fingers = 0, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
472 	unsigned int width = 0, pres = 0;
473 
474 	/* byte 0: n1  n0   .   .   .   .   R   L */
475 	fingers = (packet[0] & 0xc0) >> 6;
476 
477 	switch (fingers) {
478 	case 3:
479 	case 1:
480 		/*
481 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
482 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
483 		 */
484 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
485 		/*
486 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
487 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
488 		 */
489 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
490 		break;
491 
492 	case 2:
493 		if (packet_type == PACKET_V3_HEAD) {
494 			/*
495 			 * byte 1:   .    .    .    .  ax11 ax10 ax9  ax8
496 			 * byte 2: ax7  ax6  ax5  ax4  ax3  ax2  ax1  ax0
497 			 */
498 			etd->mt[0].x = ((packet[1] & 0x0f) << 8) | packet[2];
499 			/*
500 			 * byte 4:   .    .    .    .  ay11 ay10 ay9  ay8
501 			 * byte 5: ay7  ay6  ay5  ay4  ay3  ay2  ay1  ay0
502 			 */
503 			etd->mt[0].y = etd->y_max -
504 				(((packet[4] & 0x0f) << 8) | packet[5]);
505 			/*
506 			 * wait for next packet
507 			 */
508 			return;
509 		}
510 
511 		/* packet_type == PACKET_V3_TAIL */
512 		x1 = etd->mt[0].x;
513 		y1 = etd->mt[0].y;
514 		x2 = ((packet[1] & 0x0f) << 8) | packet[2];
515 		y2 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
516 		break;
517 	}
518 
519 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
520 	width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
521 
522 	input_report_key(dev, BTN_TOUCH, fingers != 0);
523 	if (fingers != 0) {
524 		input_report_abs(dev, ABS_X, x1);
525 		input_report_abs(dev, ABS_Y, y1);
526 	}
527 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
528 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
529 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
530 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
531 
532 	/* For clickpads map both buttons to BTN_LEFT */
533 	if (etd->fw_version & 0x001000) {
534 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
535 	} else {
536 		input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
537 		input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
538 	}
539 
540 	input_report_abs(dev, ABS_PRESSURE, pres);
541 	input_report_abs(dev, ABS_TOOL_WIDTH, width);
542 
543 	input_sync(dev);
544 }
545 
546 static void elantech_input_sync_v4(struct psmouse *psmouse)
547 {
548 	struct input_dev *dev = psmouse->dev;
549 	struct elantech_data *etd = psmouse->private;
550 	unsigned char *packet = psmouse->packet;
551 
552 	/* For clickpads map both buttons to BTN_LEFT */
553 	if (etd->fw_version & 0x001000) {
554 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
555 	} else {
556 		input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
557 		input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
558 		input_report_key(dev, BTN_MIDDLE, packet[0] & 0x04);
559 	}
560 
561 	input_mt_report_pointer_emulation(dev, true);
562 	input_sync(dev);
563 }
564 
565 static void process_packet_status_v4(struct psmouse *psmouse)
566 {
567 	struct input_dev *dev = psmouse->dev;
568 	unsigned char *packet = psmouse->packet;
569 	unsigned fingers;
570 	int i;
571 
572 	/* notify finger state change */
573 	fingers = packet[1] & 0x1f;
574 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
575 		if ((fingers & (1 << i)) == 0) {
576 			input_mt_slot(dev, i);
577 			input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
578 		}
579 	}
580 
581 	elantech_input_sync_v4(psmouse);
582 }
583 
584 static void process_packet_head_v4(struct psmouse *psmouse)
585 {
586 	struct input_dev *dev = psmouse->dev;
587 	struct elantech_data *etd = psmouse->private;
588 	unsigned char *packet = psmouse->packet;
589 	int id = ((packet[3] & 0xe0) >> 5) - 1;
590 	int pres, traces;
591 
592 	if (id < 0)
593 		return;
594 
595 	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
596 	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
597 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
598 	traces = (packet[0] & 0xf0) >> 4;
599 
600 	input_mt_slot(dev, id);
601 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
602 
603 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
604 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
605 	input_report_abs(dev, ABS_MT_PRESSURE, pres);
606 	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, traces * etd->width);
607 	/* report this for backwards compatibility */
608 	input_report_abs(dev, ABS_TOOL_WIDTH, traces);
609 
610 	elantech_input_sync_v4(psmouse);
611 }
612 
613 static void process_packet_motion_v4(struct psmouse *psmouse)
614 {
615 	struct input_dev *dev = psmouse->dev;
616 	struct elantech_data *etd = psmouse->private;
617 	unsigned char *packet = psmouse->packet;
618 	int weight, delta_x1 = 0, delta_y1 = 0, delta_x2 = 0, delta_y2 = 0;
619 	int id, sid;
620 
621 	id = ((packet[0] & 0xe0) >> 5) - 1;
622 	if (id < 0)
623 		return;
624 
625 	sid = ((packet[3] & 0xe0) >> 5) - 1;
626 	weight = (packet[0] & 0x10) ? ETP_WEIGHT_VALUE : 1;
627 	/*
628 	 * Motion packets give us the delta of x, y values of specific fingers,
629 	 * but in two's complement. Let the compiler do the conversion for us.
630 	 * Also _enlarge_ the numbers to int, in case of overflow.
631 	 */
632 	delta_x1 = (signed char)packet[1];
633 	delta_y1 = (signed char)packet[2];
634 	delta_x2 = (signed char)packet[4];
635 	delta_y2 = (signed char)packet[5];
636 
637 	etd->mt[id].x += delta_x1 * weight;
638 	etd->mt[id].y -= delta_y1 * weight;
639 	input_mt_slot(dev, id);
640 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
641 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
642 
643 	if (sid >= 0) {
644 		etd->mt[sid].x += delta_x2 * weight;
645 		etd->mt[sid].y -= delta_y2 * weight;
646 		input_mt_slot(dev, sid);
647 		input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[sid].x);
648 		input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[sid].y);
649 	}
650 
651 	elantech_input_sync_v4(psmouse);
652 }
653 
654 static void elantech_report_absolute_v4(struct psmouse *psmouse,
655 					int packet_type)
656 {
657 	switch (packet_type) {
658 	case PACKET_V4_STATUS:
659 		process_packet_status_v4(psmouse);
660 		break;
661 
662 	case PACKET_V4_HEAD:
663 		process_packet_head_v4(psmouse);
664 		break;
665 
666 	case PACKET_V4_MOTION:
667 		process_packet_motion_v4(psmouse);
668 		break;
669 
670 	case PACKET_UNKNOWN:
671 	default:
672 		/* impossible to get here */
673 		break;
674 	}
675 }
676 
677 static int elantech_packet_check_v1(struct psmouse *psmouse)
678 {
679 	struct elantech_data *etd = psmouse->private;
680 	unsigned char *packet = psmouse->packet;
681 	unsigned char p1, p2, p3;
682 
683 	/* Parity bits are placed differently */
684 	if (etd->fw_version < 0x020000) {
685 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
686 		p1 = (packet[0] & 0x20) >> 5;
687 		p2 = (packet[0] & 0x10) >> 4;
688 	} else {
689 		/* byte 0: n1  n0  p2  p1   1  p3   R   L */
690 		p1 = (packet[0] & 0x10) >> 4;
691 		p2 = (packet[0] & 0x20) >> 5;
692 	}
693 
694 	p3 = (packet[0] & 0x04) >> 2;
695 
696 	return etd->parity[packet[1]] == p1 &&
697 	       etd->parity[packet[2]] == p2 &&
698 	       etd->parity[packet[3]] == p3;
699 }
700 
701 static int elantech_debounce_check_v2(struct psmouse *psmouse)
702 {
703         /*
704          * When we encounter packet that matches this exactly, it means the
705          * hardware is in debounce status. Just ignore the whole packet.
706          */
707         const u8 debounce_packet[] = { 0x84, 0xff, 0xff, 0x02, 0xff, 0xff };
708         unsigned char *packet = psmouse->packet;
709 
710         return !memcmp(packet, debounce_packet, sizeof(debounce_packet));
711 }
712 
713 static int elantech_packet_check_v2(struct psmouse *psmouse)
714 {
715 	struct elantech_data *etd = psmouse->private;
716 	unsigned char *packet = psmouse->packet;
717 
718 	/*
719 	 * V2 hardware has two flavors. Older ones that do not report pressure,
720 	 * and newer ones that reports pressure and width. With newer ones, all
721 	 * packets (1, 2, 3 finger touch) have the same constant bits. With
722 	 * older ones, 1/3 finger touch packets and 2 finger touch packets
723 	 * have different constant bits.
724 	 * With all three cases, if the constant bits are not exactly what I
725 	 * expected, I consider them invalid.
726 	 */
727 	if (etd->reports_pressure)
728 		return (packet[0] & 0x0c) == 0x04 &&
729 		       (packet[3] & 0x0f) == 0x02;
730 
731 	if ((packet[0] & 0xc0) == 0x80)
732 		return (packet[0] & 0x0c) == 0x0c &&
733 		       (packet[3] & 0x0e) == 0x08;
734 
735 	return (packet[0] & 0x3c) == 0x3c &&
736 	       (packet[1] & 0xf0) == 0x00 &&
737 	       (packet[3] & 0x3e) == 0x38 &&
738 	       (packet[4] & 0xf0) == 0x00;
739 }
740 
741 /*
742  * We check the constant bits to determine what packet type we get,
743  * so packet checking is mandatory for v3 and later hardware.
744  */
745 static int elantech_packet_check_v3(struct psmouse *psmouse)
746 {
747 	struct elantech_data *etd = psmouse->private;
748 	const u8 debounce_packet[] = { 0xc4, 0xff, 0xff, 0x02, 0xff, 0xff };
749 	unsigned char *packet = psmouse->packet;
750 
751 	/*
752 	 * check debounce first, it has the same signature in byte 0
753 	 * and byte 3 as PACKET_V3_HEAD.
754 	 */
755 	if (!memcmp(packet, debounce_packet, sizeof(debounce_packet)))
756 		return PACKET_DEBOUNCE;
757 
758 	/*
759 	 * If the hardware flag 'crc_enabled' is set the packets have
760 	 * different signatures.
761 	 */
762 	if (etd->crc_enabled) {
763 		if ((packet[3] & 0x09) == 0x08)
764 			return PACKET_V3_HEAD;
765 
766 		if ((packet[3] & 0x09) == 0x09)
767 			return PACKET_V3_TAIL;
768 	} else {
769 		if ((packet[0] & 0x0c) == 0x04 && (packet[3] & 0xcf) == 0x02)
770 			return PACKET_V3_HEAD;
771 
772 		if ((packet[0] & 0x0c) == 0x0c && (packet[3] & 0xce) == 0x0c)
773 			return PACKET_V3_TAIL;
774 		if ((packet[3] & 0x0f) == 0x06)
775 			return PACKET_TRACKPOINT;
776 	}
777 
778 	return PACKET_UNKNOWN;
779 }
780 
781 static int elantech_packet_check_v4(struct psmouse *psmouse)
782 {
783 	struct elantech_data *etd = psmouse->private;
784 	unsigned char *packet = psmouse->packet;
785 	unsigned char packet_type = packet[3] & 0x03;
786 	bool sanity_check;
787 
788 	if (etd->tp_dev && (packet[3] & 0x0f) == 0x06)
789 		return PACKET_TRACKPOINT;
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' but are the same for
795 	 * every packet, regardless of the type.
796 	 */
797 	if (etd->crc_enabled)
798 		sanity_check = ((packet[3] & 0x08) == 0x00);
799 	else
800 		sanity_check = ((packet[0] & 0x0c) == 0x04 &&
801 				(packet[3] & 0x1c) == 0x10);
802 
803 	if (!sanity_check)
804 		return PACKET_UNKNOWN;
805 
806 	switch (packet_type) {
807 	case 0:
808 		return PACKET_V4_STATUS;
809 
810 	case 1:
811 		return PACKET_V4_HEAD;
812 
813 	case 2:
814 		return PACKET_V4_MOTION;
815 	}
816 
817 	return PACKET_UNKNOWN;
818 }
819 
820 /*
821  * Process byte stream from mouse and handle complete packets
822  */
823 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
824 {
825 	struct elantech_data *etd = psmouse->private;
826 	int packet_type;
827 
828 	if (psmouse->pktcnt < psmouse->pktsize)
829 		return PSMOUSE_GOOD_DATA;
830 
831 	if (etd->debug > 1)
832 		elantech_packet_dump(psmouse);
833 
834 	switch (etd->hw_version) {
835 	case 1:
836 		if (etd->paritycheck && !elantech_packet_check_v1(psmouse))
837 			return PSMOUSE_BAD_DATA;
838 
839 		elantech_report_absolute_v1(psmouse);
840 		break;
841 
842 	case 2:
843 		/* ignore debounce */
844 		if (elantech_debounce_check_v2(psmouse))
845 			return PSMOUSE_FULL_PACKET;
846 
847 		if (etd->paritycheck && !elantech_packet_check_v2(psmouse))
848 			return PSMOUSE_BAD_DATA;
849 
850 		elantech_report_absolute_v2(psmouse);
851 		break;
852 
853 	case 3:
854 		packet_type = elantech_packet_check_v3(psmouse);
855 		switch (packet_type) {
856 		case PACKET_UNKNOWN:
857 			return PSMOUSE_BAD_DATA;
858 
859 		case PACKET_DEBOUNCE:
860 			/* ignore debounce */
861 			break;
862 
863 		case PACKET_TRACKPOINT:
864 			elantech_report_trackpoint(psmouse, packet_type);
865 			break;
866 
867 		default:
868 			elantech_report_absolute_v3(psmouse, packet_type);
869 			break;
870 		}
871 
872 		break;
873 
874 	case 4:
875 		packet_type = elantech_packet_check_v4(psmouse);
876 		switch (packet_type) {
877 		case PACKET_UNKNOWN:
878 			return PSMOUSE_BAD_DATA;
879 
880 		case PACKET_TRACKPOINT:
881 			elantech_report_trackpoint(psmouse, packet_type);
882 			break;
883 
884 		default:
885 			elantech_report_absolute_v4(psmouse, packet_type);
886 			break;
887 		}
888 
889 		break;
890 	}
891 
892 	return PSMOUSE_FULL_PACKET;
893 }
894 
895 /*
896  * Put the touchpad into absolute mode
897  */
898 static int elantech_set_absolute_mode(struct psmouse *psmouse)
899 {
900 	struct elantech_data *etd = psmouse->private;
901 	unsigned char val;
902 	int tries = ETP_READ_BACK_TRIES;
903 	int rc = 0;
904 
905 	switch (etd->hw_version) {
906 	case 1:
907 		etd->reg_10 = 0x16;
908 		etd->reg_11 = 0x8f;
909 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
910 		    elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
911 			rc = -1;
912 		}
913 		break;
914 
915 	case 2:
916 					/* Windows driver values */
917 		etd->reg_10 = 0x54;
918 		etd->reg_11 = 0x88;	/* 0x8a */
919 		etd->reg_21 = 0x60;	/* 0x00 */
920 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
921 		    elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
922 		    elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
923 			rc = -1;
924 		}
925 		break;
926 
927 	case 3:
928 		if (etd->set_hw_resolution)
929 			etd->reg_10 = 0x0b;
930 		else
931 			etd->reg_10 = 0x01;
932 
933 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10))
934 			rc = -1;
935 
936 		break;
937 
938 	case 4:
939 		etd->reg_07 = 0x01;
940 		if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
941 			rc = -1;
942 
943 		goto skip_readback_reg_10; /* v4 has no reg 0x10 to read */
944 	}
945 
946 	if (rc == 0) {
947 		/*
948 		 * Read back reg 0x10. For hardware version 1 we must make
949 		 * sure the absolute mode bit is set. For hardware version 2
950 		 * the touchpad is probably initializing and not ready until
951 		 * we read back the value we just wrote.
952 		 */
953 		do {
954 			rc = elantech_read_reg(psmouse, 0x10, &val);
955 			if (rc == 0)
956 				break;
957 			tries--;
958 			elantech_debug("retrying read (%d).\n", tries);
959 			msleep(ETP_READ_BACK_DELAY);
960 		} while (tries > 0);
961 
962 		if (rc) {
963 			psmouse_err(psmouse,
964 				    "failed to read back register 0x10.\n");
965 		} else if (etd->hw_version == 1 &&
966 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
967 			psmouse_err(psmouse,
968 				    "touchpad refuses to switch to absolute mode.\n");
969 			rc = -1;
970 		}
971 	}
972 
973  skip_readback_reg_10:
974 	if (rc)
975 		psmouse_err(psmouse, "failed to initialise registers.\n");
976 
977 	return rc;
978 }
979 
980 static int elantech_set_range(struct psmouse *psmouse,
981 			      unsigned int *x_min, unsigned int *y_min,
982 			      unsigned int *x_max, unsigned int *y_max,
983 			      unsigned int *width)
984 {
985 	struct elantech_data *etd = psmouse->private;
986 	unsigned char param[3];
987 	unsigned char traces;
988 
989 	switch (etd->hw_version) {
990 	case 1:
991 		*x_min = ETP_XMIN_V1;
992 		*y_min = ETP_YMIN_V1;
993 		*x_max = ETP_XMAX_V1;
994 		*y_max = ETP_YMAX_V1;
995 		break;
996 
997 	case 2:
998 		if (etd->fw_version == 0x020800 ||
999 		    etd->fw_version == 0x020b00 ||
1000 		    etd->fw_version == 0x020030) {
1001 			*x_min = ETP_XMIN_V2;
1002 			*y_min = ETP_YMIN_V2;
1003 			*x_max = ETP_XMAX_V2;
1004 			*y_max = ETP_YMAX_V2;
1005 		} else {
1006 			int i;
1007 			int fixed_dpi;
1008 
1009 			i = (etd->fw_version > 0x020800 &&
1010 			     etd->fw_version < 0x020900) ? 1 : 2;
1011 
1012 			if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1013 				return -1;
1014 
1015 			fixed_dpi = param[1] & 0x10;
1016 
1017 			if (((etd->fw_version >> 16) == 0x14) && fixed_dpi) {
1018 				if (etd->send_cmd(psmouse, ETP_SAMPLE_QUERY, param))
1019 					return -1;
1020 
1021 				*x_max = (etd->capabilities[1] - i) * param[1] / 2;
1022 				*y_max = (etd->capabilities[2] - i) * param[2] / 2;
1023 			} else if (etd->fw_version == 0x040216) {
1024 				*x_max = 819;
1025 				*y_max = 405;
1026 			} else if (etd->fw_version == 0x040219 || etd->fw_version == 0x040215) {
1027 				*x_max = 900;
1028 				*y_max = 500;
1029 			} else {
1030 				*x_max = (etd->capabilities[1] - i) * 64;
1031 				*y_max = (etd->capabilities[2] - i) * 64;
1032 			}
1033 		}
1034 		break;
1035 
1036 	case 3:
1037 		if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1038 			return -1;
1039 
1040 		*x_max = (0x0f & param[0]) << 8 | param[1];
1041 		*y_max = (0xf0 & param[0]) << 4 | param[2];
1042 		break;
1043 
1044 	case 4:
1045 		if (etd->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1046 			return -1;
1047 
1048 		*x_max = (0x0f & param[0]) << 8 | param[1];
1049 		*y_max = (0xf0 & param[0]) << 4 | param[2];
1050 		traces = etd->capabilities[1];
1051 		if ((traces < 2) || (traces > *x_max))
1052 			return -1;
1053 
1054 		*width = *x_max / (traces - 1);
1055 		break;
1056 	}
1057 
1058 	return 0;
1059 }
1060 
1061 /*
1062  * (value from firmware) * 10 + 790 = dpi
1063  * we also have to convert dpi to dots/mm (*10/254 to avoid floating point)
1064  */
1065 static unsigned int elantech_convert_res(unsigned int val)
1066 {
1067 	return (val * 10 + 790) * 10 / 254;
1068 }
1069 
1070 static int elantech_get_resolution_v4(struct psmouse *psmouse,
1071 				      unsigned int *x_res,
1072 				      unsigned int *y_res)
1073 {
1074 	unsigned char param[3];
1075 
1076 	if (elantech_send_cmd(psmouse, ETP_RESOLUTION_QUERY, param))
1077 		return -1;
1078 
1079 	*x_res = elantech_convert_res(param[1] & 0x0f);
1080 	*y_res = elantech_convert_res((param[1] & 0xf0) >> 4);
1081 
1082 	return 0;
1083 }
1084 
1085 /*
1086  * Advertise INPUT_PROP_BUTTONPAD for clickpads. The testing of bit 12 in
1087  * fw_version for this is based on the following fw_version & caps table:
1088  *
1089  * Laptop-model:           fw_version:     caps:           buttons:
1090  * Acer S3                 0x461f00        10, 13, 0e      clickpad
1091  * Acer S7-392             0x581f01        50, 17, 0d      clickpad
1092  * Acer V5-131             0x461f02        01, 16, 0c      clickpad
1093  * Acer V5-551             0x461f00        ?               clickpad
1094  * Asus K53SV              0x450f01        78, 15, 0c      2 hw buttons
1095  * Asus G46VW              0x460f02        00, 18, 0c      2 hw buttons
1096  * Asus G750JX             0x360f00        00, 16, 0c      2 hw buttons
1097  * Asus UX31               0x361f00        20, 15, 0e      clickpad
1098  * Asus UX32VD             0x361f02        00, 15, 0e      clickpad
1099  * Avatar AVIU-145A2       0x361f00        ?               clickpad
1100  * Fujitsu LIFEBOOK E544   0x470f00        d0, 12, 09      2 hw buttons
1101  * Fujitsu LIFEBOOK E554   0x570f01        40, 14, 0c      2 hw buttons
1102  * Fujitsu H730            0x570f00        c0, 14, 0c      3 hw buttons (**)
1103  * Gigabyte U2442          0x450f01        58, 17, 0c      2 hw buttons
1104  * Lenovo L430             0x350f02        b9, 15, 0c      2 hw buttons (*)
1105  * Lenovo L530             0x350f02        b9, 15, 0c      2 hw buttons (*)
1106  * Samsung NF210           0x150b00        78, 14, 0a      2 hw buttons
1107  * Samsung NP770Z5E        0x575f01        10, 15, 0f      clickpad
1108  * Samsung NP700Z5B        0x361f06        21, 15, 0f      clickpad
1109  * Samsung NP900X3E-A02    0x575f03        ?               clickpad
1110  * Samsung NP-QX410        0x851b00        19, 14, 0c      clickpad
1111  * Samsung RC512           0x450f00        08, 15, 0c      2 hw buttons
1112  * Samsung RF710           0x450f00        ?               2 hw buttons
1113  * System76 Pangolin       0x250f01        ?               2 hw buttons
1114  * (*) + 3 trackpoint buttons
1115  * (**) + 0 trackpoint buttons
1116  * Note: Lenovo L430 and Lenovo L430 have the same fw_version/caps
1117  */
1118 static void elantech_set_buttonpad_prop(struct psmouse *psmouse)
1119 {
1120 	struct input_dev *dev = psmouse->dev;
1121 	struct elantech_data *etd = psmouse->private;
1122 
1123 	if (etd->fw_version & 0x001000) {
1124 		__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
1125 		__clear_bit(BTN_RIGHT, dev->keybit);
1126 	}
1127 }
1128 
1129 /*
1130  * Some hw_version 4 models do have a middle button
1131  */
1132 static const struct dmi_system_id elantech_dmi_has_middle_button[] = {
1133 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1134 	{
1135 		/* Fujitsu H730 has a middle button */
1136 		.matches = {
1137 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1138 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1139 		},
1140 	},
1141 #endif
1142 	{ }
1143 };
1144 
1145 /*
1146  * Set the appropriate event bits for the input subsystem
1147  */
1148 static int elantech_set_input_params(struct psmouse *psmouse)
1149 {
1150 	struct input_dev *dev = psmouse->dev;
1151 	struct elantech_data *etd = psmouse->private;
1152 	unsigned int x_min = 0, y_min = 0, x_max = 0, y_max = 0, width = 0;
1153 	unsigned int x_res = 0, y_res = 0;
1154 
1155 	if (elantech_set_range(psmouse, &x_min, &y_min, &x_max, &y_max, &width))
1156 		return -1;
1157 
1158 	__set_bit(INPUT_PROP_POINTER, dev->propbit);
1159 	__set_bit(EV_KEY, dev->evbit);
1160 	__set_bit(EV_ABS, dev->evbit);
1161 	__clear_bit(EV_REL, dev->evbit);
1162 
1163 	__set_bit(BTN_LEFT, dev->keybit);
1164 	if (dmi_check_system(elantech_dmi_has_middle_button))
1165 		__set_bit(BTN_MIDDLE, dev->keybit);
1166 	__set_bit(BTN_RIGHT, dev->keybit);
1167 
1168 	__set_bit(BTN_TOUCH, dev->keybit);
1169 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
1170 	__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
1171 	__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
1172 
1173 	switch (etd->hw_version) {
1174 	case 1:
1175 		/* Rocker button */
1176 		if (etd->fw_version < 0x020000 &&
1177 		    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
1178 			__set_bit(BTN_FORWARD, dev->keybit);
1179 			__set_bit(BTN_BACK, dev->keybit);
1180 		}
1181 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1182 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1183 		break;
1184 
1185 	case 2:
1186 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1187 		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
1188 		/* fall through */
1189 	case 3:
1190 		if (etd->hw_version == 3)
1191 			elantech_set_buttonpad_prop(psmouse);
1192 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1193 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1194 		if (etd->reports_pressure) {
1195 			input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1196 					     ETP_PMAX_V2, 0, 0);
1197 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1198 					     ETP_WMAX_V2, 0, 0);
1199 		}
1200 		input_mt_init_slots(dev, 2, 0);
1201 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1202 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1203 		break;
1204 
1205 	case 4:
1206 		if (elantech_get_resolution_v4(psmouse, &x_res, &y_res)) {
1207 			/*
1208 			 * if query failed, print a warning and leave the values
1209 			 * zero to resemble synaptics.c behavior.
1210 			 */
1211 			psmouse_warn(psmouse, "couldn't query resolution data.\n");
1212 		}
1213 		elantech_set_buttonpad_prop(psmouse);
1214 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1215 		/* For X to recognize me as touchpad. */
1216 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1217 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1218 		input_abs_set_res(dev, ABS_X, x_res);
1219 		input_abs_set_res(dev, ABS_Y, y_res);
1220 		/*
1221 		 * range of pressure and width is the same as v2,
1222 		 * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
1223 		 */
1224 		input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1225 				     ETP_PMAX_V2, 0, 0);
1226 		input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1227 				     ETP_WMAX_V2, 0, 0);
1228 		/* Multitouch capable pad, up to 5 fingers. */
1229 		input_mt_init_slots(dev, ETP_MAX_FINGERS, 0);
1230 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1231 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1232 		input_abs_set_res(dev, ABS_MT_POSITION_X, x_res);
1233 		input_abs_set_res(dev, ABS_MT_POSITION_Y, y_res);
1234 		input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
1235 				     ETP_PMAX_V2, 0, 0);
1236 		/*
1237 		 * The firmware reports how many trace lines the finger spans,
1238 		 * convert to surface unit as Protocol-B requires.
1239 		 */
1240 		input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 0,
1241 				     ETP_WMAX_V2 * width, 0, 0);
1242 		break;
1243 	}
1244 
1245 	etd->y_max = y_max;
1246 	etd->width = width;
1247 
1248 	return 0;
1249 }
1250 
1251 struct elantech_attr_data {
1252 	size_t		field_offset;
1253 	unsigned char	reg;
1254 };
1255 
1256 /*
1257  * Display a register value by reading a sysfs entry
1258  */
1259 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
1260 					char *buf)
1261 {
1262 	struct elantech_data *etd = psmouse->private;
1263 	struct elantech_attr_data *attr = data;
1264 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1265 	int rc = 0;
1266 
1267 	if (attr->reg)
1268 		rc = elantech_read_reg(psmouse, attr->reg, reg);
1269 
1270 	return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
1271 }
1272 
1273 /*
1274  * Write a register value by writing a sysfs entry
1275  */
1276 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
1277 				     void *data, const char *buf, size_t count)
1278 {
1279 	struct elantech_data *etd = psmouse->private;
1280 	struct elantech_attr_data *attr = data;
1281 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1282 	unsigned char value;
1283 	int err;
1284 
1285 	err = kstrtou8(buf, 16, &value);
1286 	if (err)
1287 		return err;
1288 
1289 	/* Do we need to preserve some bits for version 2 hardware too? */
1290 	if (etd->hw_version == 1) {
1291 		if (attr->reg == 0x10)
1292 			/* Force absolute mode always on */
1293 			value |= ETP_R10_ABSOLUTE_MODE;
1294 		else if (attr->reg == 0x11)
1295 			/* Force 4 byte mode always on */
1296 			value |= ETP_R11_4_BYTE_MODE;
1297 	}
1298 
1299 	if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
1300 		*reg = value;
1301 
1302 	return count;
1303 }
1304 
1305 #define ELANTECH_INT_ATTR(_name, _register)				\
1306 	static struct elantech_attr_data elantech_attr_##_name = {	\
1307 		.field_offset = offsetof(struct elantech_data, _name),	\
1308 		.reg = _register,					\
1309 	};								\
1310 	PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,			\
1311 			    &elantech_attr_##_name,			\
1312 			    elantech_show_int_attr,			\
1313 			    elantech_set_int_attr)
1314 
1315 ELANTECH_INT_ATTR(reg_07, 0x07);
1316 ELANTECH_INT_ATTR(reg_10, 0x10);
1317 ELANTECH_INT_ATTR(reg_11, 0x11);
1318 ELANTECH_INT_ATTR(reg_20, 0x20);
1319 ELANTECH_INT_ATTR(reg_21, 0x21);
1320 ELANTECH_INT_ATTR(reg_22, 0x22);
1321 ELANTECH_INT_ATTR(reg_23, 0x23);
1322 ELANTECH_INT_ATTR(reg_24, 0x24);
1323 ELANTECH_INT_ATTR(reg_25, 0x25);
1324 ELANTECH_INT_ATTR(reg_26, 0x26);
1325 ELANTECH_INT_ATTR(debug, 0);
1326 ELANTECH_INT_ATTR(paritycheck, 0);
1327 ELANTECH_INT_ATTR(crc_enabled, 0);
1328 
1329 static struct attribute *elantech_attrs[] = {
1330 	&psmouse_attr_reg_07.dattr.attr,
1331 	&psmouse_attr_reg_10.dattr.attr,
1332 	&psmouse_attr_reg_11.dattr.attr,
1333 	&psmouse_attr_reg_20.dattr.attr,
1334 	&psmouse_attr_reg_21.dattr.attr,
1335 	&psmouse_attr_reg_22.dattr.attr,
1336 	&psmouse_attr_reg_23.dattr.attr,
1337 	&psmouse_attr_reg_24.dattr.attr,
1338 	&psmouse_attr_reg_25.dattr.attr,
1339 	&psmouse_attr_reg_26.dattr.attr,
1340 	&psmouse_attr_debug.dattr.attr,
1341 	&psmouse_attr_paritycheck.dattr.attr,
1342 	&psmouse_attr_crc_enabled.dattr.attr,
1343 	NULL
1344 };
1345 
1346 static struct attribute_group elantech_attr_group = {
1347 	.attrs = elantech_attrs,
1348 };
1349 
1350 static bool elantech_is_signature_valid(const unsigned char *param)
1351 {
1352 	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
1353 	int i;
1354 
1355 	if (param[0] == 0)
1356 		return false;
1357 
1358 	if (param[1] == 0)
1359 		return true;
1360 
1361 	/*
1362 	 * Some models have a revision higher then 20. Meaning param[2] may
1363 	 * be 10 or 20, skip the rates check for these.
1364 	 */
1365 	if (param[0] == 0x46 && (param[1] & 0xef) == 0x0f && param[2] < 40)
1366 		return true;
1367 
1368 	for (i = 0; i < ARRAY_SIZE(rates); i++)
1369 		if (param[2] == rates[i])
1370 			return false;
1371 
1372 	return true;
1373 }
1374 
1375 /*
1376  * Use magic knock to detect Elantech touchpad
1377  */
1378 int elantech_detect(struct psmouse *psmouse, bool set_properties)
1379 {
1380 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1381 	unsigned char param[3];
1382 
1383 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1384 
1385 	if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
1386 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1387 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1388 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1389 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1390 		psmouse_dbg(psmouse, "sending Elantech magic knock failed.\n");
1391 		return -1;
1392 	}
1393 
1394 	/*
1395 	 * Report this in case there are Elantech models that use a different
1396 	 * set of magic numbers
1397 	 */
1398 	if (param[0] != 0x3c || param[1] != 0x03 ||
1399 	    (param[2] != 0xc8 && param[2] != 0x00)) {
1400 		psmouse_dbg(psmouse,
1401 			    "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
1402 			    param[0], param[1], param[2]);
1403 		return -1;
1404 	}
1405 
1406 	/*
1407 	 * Query touchpad's firmware version and see if it reports known
1408 	 * value to avoid mis-detection. Logitech mice are known to respond
1409 	 * to Elantech magic knock and there might be more.
1410 	 */
1411 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1412 		psmouse_dbg(psmouse, "failed to query firmware version.\n");
1413 		return -1;
1414 	}
1415 
1416 	psmouse_dbg(psmouse,
1417 		    "Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
1418 		    param[0], param[1], param[2]);
1419 
1420 	if (!elantech_is_signature_valid(param)) {
1421 		psmouse_dbg(psmouse,
1422 			    "Probably not a real Elantech touchpad. Aborting.\n");
1423 		return -1;
1424 	}
1425 
1426 	if (set_properties) {
1427 		psmouse->vendor = "Elantech";
1428 		psmouse->name = "Touchpad";
1429 	}
1430 
1431 	return 0;
1432 }
1433 
1434 /*
1435  * Clean up sysfs entries when disconnecting
1436  */
1437 static void elantech_disconnect(struct psmouse *psmouse)
1438 {
1439 	struct elantech_data *etd = psmouse->private;
1440 
1441 	if (etd->tp_dev)
1442 		input_unregister_device(etd->tp_dev);
1443 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1444 			   &elantech_attr_group);
1445 	kfree(psmouse->private);
1446 	psmouse->private = NULL;
1447 }
1448 
1449 /*
1450  * Put the touchpad back into absolute mode when reconnecting
1451  */
1452 static int elantech_reconnect(struct psmouse *psmouse)
1453 {
1454 	psmouse_reset(psmouse);
1455 
1456 	if (elantech_detect(psmouse, 0))
1457 		return -1;
1458 
1459 	if (elantech_set_absolute_mode(psmouse)) {
1460 		psmouse_err(psmouse,
1461 			    "failed to put touchpad back into absolute mode.\n");
1462 		return -1;
1463 	}
1464 
1465 	return 0;
1466 }
1467 
1468 /*
1469  * Some hw_version 4 models do not work with crc_disabled
1470  */
1471 static const struct dmi_system_id elantech_dmi_force_crc_enabled[] = {
1472 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1473 	{
1474 		/* Fujitsu H730 does not work with crc_enabled == 0 */
1475 		.matches = {
1476 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1477 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1478 		},
1479 	},
1480 	{
1481 		/* Fujitsu LIFEBOOK E554  does not work with crc_enabled == 0 */
1482 		.matches = {
1483 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1484 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E554"),
1485 		},
1486 	},
1487 	{
1488 		/* Fujitsu LIFEBOOK E544  does not work with crc_enabled == 0 */
1489 		.matches = {
1490 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1491 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E544"),
1492 		},
1493 	},
1494 #endif
1495 	{ }
1496 };
1497 
1498 /*
1499  * Some hw_version 3 models go into error state when we try to set
1500  * bit 3 and/or bit 1 of r10.
1501  */
1502 static const struct dmi_system_id no_hw_res_dmi_table[] = {
1503 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1504 	{
1505 		/* Gigabyte U2442 */
1506 		.matches = {
1507 			DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
1508 			DMI_MATCH(DMI_PRODUCT_NAME, "U2442"),
1509 		},
1510 	},
1511 #endif
1512 	{ }
1513 };
1514 
1515 /*
1516  * determine hardware version and set some properties according to it.
1517  */
1518 static int elantech_set_properties(struct elantech_data *etd)
1519 {
1520 	/* This represents the version of IC body. */
1521 	int ver = (etd->fw_version & 0x0f0000) >> 16;
1522 
1523 	/* Early version of Elan touchpads doesn't obey the rule. */
1524 	if (etd->fw_version < 0x020030 || etd->fw_version == 0x020600)
1525 		etd->hw_version = 1;
1526 	else {
1527 		switch (ver) {
1528 		case 2:
1529 		case 4:
1530 			etd->hw_version = 2;
1531 			break;
1532 		case 5:
1533 			etd->hw_version = 3;
1534 			break;
1535 		case 6:
1536 		case 7:
1537 		case 8:
1538 		case 9:
1539 		case 10:
1540 		case 13:
1541 			etd->hw_version = 4;
1542 			break;
1543 		default:
1544 			return -1;
1545 		}
1546 	}
1547 
1548 	/* decide which send_cmd we're gonna use early */
1549 	etd->send_cmd = etd->hw_version >= 3 ? elantech_send_cmd :
1550 					       synaptics_send_cmd;
1551 
1552 	/* Turn on packet checking by default */
1553 	etd->paritycheck = 1;
1554 
1555 	/*
1556 	 * This firmware suffers from misreporting coordinates when
1557 	 * a touch action starts causing the mouse cursor or scrolled page
1558 	 * to jump. Enable a workaround.
1559 	 */
1560 	etd->jumpy_cursor =
1561 		(etd->fw_version == 0x020022 || etd->fw_version == 0x020600);
1562 
1563 	if (etd->hw_version > 1) {
1564 		/* For now show extra debug information */
1565 		etd->debug = 1;
1566 
1567 		if (etd->fw_version >= 0x020800)
1568 			etd->reports_pressure = true;
1569 	}
1570 
1571 	/*
1572 	 * The signatures of v3 and v4 packets change depending on the
1573 	 * value of this hardware flag.
1574 	 */
1575 	etd->crc_enabled = (etd->fw_version & 0x4000) == 0x4000 ||
1576 			   dmi_check_system(elantech_dmi_force_crc_enabled);
1577 
1578 	/* Enable real hardware resolution on hw_version 3 ? */
1579 	etd->set_hw_resolution = !dmi_check_system(no_hw_res_dmi_table);
1580 
1581 	return 0;
1582 }
1583 
1584 /*
1585  * Initialize the touchpad and create sysfs entries
1586  */
1587 int elantech_init(struct psmouse *psmouse)
1588 {
1589 	struct elantech_data *etd;
1590 	int i;
1591 	int error = -EINVAL;
1592 	unsigned char param[3];
1593 	struct input_dev *tp_dev;
1594 
1595 	psmouse->private = etd = kzalloc(sizeof(struct elantech_data), GFP_KERNEL);
1596 	if (!etd)
1597 		return -ENOMEM;
1598 
1599 	psmouse_reset(psmouse);
1600 
1601 	etd->parity[0] = 1;
1602 	for (i = 1; i < 256; i++)
1603 		etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
1604 
1605 	/*
1606 	 * Do the version query again so we can store the result
1607 	 */
1608 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1609 		psmouse_err(psmouse, "failed to query firmware version.\n");
1610 		goto init_fail;
1611 	}
1612 	etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
1613 
1614 	if (elantech_set_properties(etd)) {
1615 		psmouse_err(psmouse, "unknown hardware version, aborting...\n");
1616 		goto init_fail;
1617 	}
1618 	psmouse_info(psmouse,
1619 		     "assuming hardware version %d (with firmware version 0x%02x%02x%02x)\n",
1620 		     etd->hw_version, param[0], param[1], param[2]);
1621 
1622 	if (etd->send_cmd(psmouse, ETP_CAPABILITIES_QUERY,
1623 	    etd->capabilities)) {
1624 		psmouse_err(psmouse, "failed to query capabilities.\n");
1625 		goto init_fail;
1626 	}
1627 	psmouse_info(psmouse,
1628 		     "Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
1629 		     etd->capabilities[0], etd->capabilities[1],
1630 		     etd->capabilities[2]);
1631 
1632 	if (elantech_set_absolute_mode(psmouse)) {
1633 		psmouse_err(psmouse,
1634 			    "failed to put touchpad into absolute mode.\n");
1635 		goto init_fail;
1636 	}
1637 
1638 	if (elantech_set_input_params(psmouse)) {
1639 		psmouse_err(psmouse, "failed to query touchpad range.\n");
1640 		goto init_fail;
1641 	}
1642 
1643 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
1644 				   &elantech_attr_group);
1645 	if (error) {
1646 		psmouse_err(psmouse,
1647 			    "failed to create sysfs attributes, error: %d.\n",
1648 			    error);
1649 		goto init_fail;
1650 	}
1651 
1652 	/* The MSB indicates the presence of the trackpoint */
1653 	if ((etd->capabilities[0] & 0x80) == 0x80) {
1654 		tp_dev = input_allocate_device();
1655 
1656 		if (!tp_dev) {
1657 			error = -ENOMEM;
1658 			goto init_fail_tp_alloc;
1659 		}
1660 
1661 		etd->tp_dev = tp_dev;
1662 		snprintf(etd->tp_phys, sizeof(etd->tp_phys), "%s/input1",
1663 			psmouse->ps2dev.serio->phys);
1664 		tp_dev->phys = etd->tp_phys;
1665 		tp_dev->name = "Elantech PS/2 TrackPoint";
1666 		tp_dev->id.bustype = BUS_I8042;
1667 		tp_dev->id.vendor  = 0x0002;
1668 		tp_dev->id.product = PSMOUSE_ELANTECH;
1669 		tp_dev->id.version = 0x0000;
1670 		tp_dev->dev.parent = &psmouse->ps2dev.serio->dev;
1671 		tp_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
1672 		tp_dev->relbit[BIT_WORD(REL_X)] =
1673 			BIT_MASK(REL_X) | BIT_MASK(REL_Y);
1674 		tp_dev->keybit[BIT_WORD(BTN_LEFT)] =
1675 			BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
1676 			BIT_MASK(BTN_RIGHT);
1677 
1678 		__set_bit(INPUT_PROP_POINTER, tp_dev->propbit);
1679 		__set_bit(INPUT_PROP_POINTING_STICK, tp_dev->propbit);
1680 
1681 		error = input_register_device(etd->tp_dev);
1682 		if (error < 0)
1683 			goto init_fail_tp_reg;
1684 	}
1685 
1686 	psmouse->protocol_handler = elantech_process_byte;
1687 	psmouse->disconnect = elantech_disconnect;
1688 	psmouse->reconnect = elantech_reconnect;
1689 	psmouse->pktsize = etd->hw_version > 1 ? 6 : 4;
1690 
1691 	return 0;
1692  init_fail_tp_reg:
1693 	input_free_device(tp_dev);
1694  init_fail_tp_alloc:
1695 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1696 			   &elantech_attr_group);
1697  init_fail:
1698 	psmouse_reset(psmouse);
1699 	kfree(etd);
1700 	return error;
1701 }
1702