xref: /openbmc/linux/drivers/input/mouse/elantech.c (revision e3d786a3)
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/i2c.h>
18 #include <linux/input.h>
19 #include <linux/input/mt.h>
20 #include <linux/platform_device.h>
21 #include <linux/serio.h>
22 #include <linux/libps2.h>
23 #include <asm/unaligned.h>
24 #include "psmouse.h"
25 #include "elantech.h"
26 #include "elan_i2c.h"
27 
28 #define elantech_debug(fmt, ...)					\
29 	do {								\
30 		if (etd->info.debug)					\
31 			psmouse_printk(KERN_DEBUG, psmouse,		\
32 					fmt, ##__VA_ARGS__);		\
33 	} while (0)
34 
35 /*
36  * Send a Synaptics style sliced query command
37  */
38 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
39 				unsigned char *param)
40 {
41 	if (ps2_sliced_command(&psmouse->ps2dev, c) ||
42 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
43 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
44 		return -1;
45 	}
46 
47 	return 0;
48 }
49 
50 /*
51  * V3 and later support this fast command
52  */
53 static int elantech_send_cmd(struct psmouse *psmouse, unsigned char c,
54 				unsigned char *param)
55 {
56 	struct ps2dev *ps2dev = &psmouse->ps2dev;
57 
58 	if (ps2_command(ps2dev, NULL, ETP_PS2_CUSTOM_COMMAND) ||
59 	    ps2_command(ps2dev, NULL, c) ||
60 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
61 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
62 		return -1;
63 	}
64 
65 	return 0;
66 }
67 
68 /*
69  * A retrying version of ps2_command
70  */
71 static int elantech_ps2_command(struct psmouse *psmouse,
72 				unsigned char *param, int command)
73 {
74 	struct ps2dev *ps2dev = &psmouse->ps2dev;
75 	struct elantech_data *etd = psmouse->private;
76 	int rc;
77 	int tries = ETP_PS2_COMMAND_TRIES;
78 
79 	do {
80 		rc = ps2_command(ps2dev, param, command);
81 		if (rc == 0)
82 			break;
83 		tries--;
84 		elantech_debug("retrying ps2 command 0x%02x (%d).\n",
85 				command, tries);
86 		msleep(ETP_PS2_COMMAND_DELAY);
87 	} while (tries > 0);
88 
89 	if (rc)
90 		psmouse_err(psmouse, "ps2 command 0x%02x failed.\n", command);
91 
92 	return rc;
93 }
94 
95 /*
96  * Send an Elantech style special command to read a value from a register
97  */
98 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
99 				unsigned char *val)
100 {
101 	struct elantech_data *etd = psmouse->private;
102 	unsigned char param[3];
103 	int rc = 0;
104 
105 	if (reg < 0x07 || reg > 0x26)
106 		return -1;
107 
108 	if (reg > 0x11 && reg < 0x20)
109 		return -1;
110 
111 	switch (etd->info.hw_version) {
112 	case 1:
113 		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_READ) ||
114 		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
115 		    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
116 			rc = -1;
117 		}
118 		break;
119 
120 	case 2:
121 		if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
122 		    elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
123 		    elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
124 		    elantech_ps2_command(psmouse,  NULL, reg) ||
125 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
126 			rc = -1;
127 		}
128 		break;
129 
130 	case 3 ... 4:
131 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
132 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
133 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
134 		    elantech_ps2_command(psmouse, NULL, reg) ||
135 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
136 			rc = -1;
137 		}
138 		break;
139 	}
140 
141 	if (rc)
142 		psmouse_err(psmouse, "failed to read register 0x%02x.\n", reg);
143 	else if (etd->info.hw_version != 4)
144 		*val = param[0];
145 	else
146 		*val = param[1];
147 
148 	return rc;
149 }
150 
151 /*
152  * Send an Elantech style special command to write a register with a value
153  */
154 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
155 				unsigned char val)
156 {
157 	struct elantech_data *etd = psmouse->private;
158 	int rc = 0;
159 
160 	if (reg < 0x07 || reg > 0x26)
161 		return -1;
162 
163 	if (reg > 0x11 && reg < 0x20)
164 		return -1;
165 
166 	switch (etd->info.hw_version) {
167 	case 1:
168 		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_WRITE) ||
169 		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
170 		    ps2_sliced_command(&psmouse->ps2dev, val) ||
171 		    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
172 			rc = -1;
173 		}
174 		break;
175 
176 	case 2:
177 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
178 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
179 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
180 		    elantech_ps2_command(psmouse, NULL, reg) ||
181 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
182 		    elantech_ps2_command(psmouse, NULL, val) ||
183 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
184 			rc = -1;
185 		}
186 		break;
187 
188 	case 3:
189 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
190 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
191 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
192 		    elantech_ps2_command(psmouse, NULL, reg) ||
193 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
194 		    elantech_ps2_command(psmouse, NULL, val) ||
195 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
196 			rc = -1;
197 		}
198 		break;
199 
200 	case 4:
201 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
202 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
203 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
204 		    elantech_ps2_command(psmouse, NULL, reg) ||
205 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
206 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
207 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
208 		    elantech_ps2_command(psmouse, NULL, val) ||
209 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
210 			rc = -1;
211 		}
212 		break;
213 	}
214 
215 	if (rc)
216 		psmouse_err(psmouse,
217 			    "failed to write register 0x%02x with value 0x%02x.\n",
218 			    reg, val);
219 
220 	return rc;
221 }
222 
223 /*
224  * Dump a complete mouse movement packet to the syslog
225  */
226 static void elantech_packet_dump(struct psmouse *psmouse)
227 {
228 	psmouse_printk(KERN_DEBUG, psmouse, "PS/2 packet [%*ph]\n",
229 		       psmouse->pktsize, psmouse->packet);
230 }
231 
232 /*
233  * Interpret complete data packets and report absolute mode input events for
234  * hardware version 1. (4 byte packets)
235  */
236 static void elantech_report_absolute_v1(struct psmouse *psmouse)
237 {
238 	struct input_dev *dev = psmouse->dev;
239 	struct elantech_data *etd = psmouse->private;
240 	unsigned char *packet = psmouse->packet;
241 	int fingers;
242 
243 	if (etd->info.fw_version < 0x020000) {
244 		/*
245 		 * byte 0:  D   U  p1  p2   1  p3   R   L
246 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
247 		 */
248 		fingers = ((packet[1] & 0x80) >> 7) +
249 				((packet[1] & 0x30) >> 4);
250 	} else {
251 		/*
252 		 * byte 0: n1  n0  p2  p1   1  p3   R   L
253 		 * byte 1:  0   0   0   0  x9  x8  y9  y8
254 		 */
255 		fingers = (packet[0] & 0xc0) >> 6;
256 	}
257 
258 	if (etd->info.jumpy_cursor) {
259 		if (fingers != 1) {
260 			etd->single_finger_reports = 0;
261 		} else if (etd->single_finger_reports < 2) {
262 			/* Discard first 2 reports of one finger, bogus */
263 			etd->single_finger_reports++;
264 			elantech_debug("discarding packet\n");
265 			return;
266 		}
267 	}
268 
269 	input_report_key(dev, BTN_TOUCH, fingers != 0);
270 
271 	/*
272 	 * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
273 	 * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
274 	 */
275 	if (fingers) {
276 		input_report_abs(dev, ABS_X,
277 			((packet[1] & 0x0c) << 6) | packet[2]);
278 		input_report_abs(dev, ABS_Y,
279 			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
280 	}
281 
282 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
283 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
284 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
285 
286 	psmouse_report_standard_buttons(dev, packet[0]);
287 
288 	if (etd->info.fw_version < 0x020000 &&
289 	    (etd->info.capabilities[0] & ETP_CAP_HAS_ROCKER)) {
290 		/* rocker up */
291 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
292 		/* rocker down */
293 		input_report_key(dev, BTN_BACK, packet[0] & 0x80);
294 	}
295 
296 	input_sync(dev);
297 }
298 
299 static void elantech_set_slot(struct input_dev *dev, int slot, bool active,
300 			      unsigned int x, unsigned int y)
301 {
302 	input_mt_slot(dev, slot);
303 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
304 	if (active) {
305 		input_report_abs(dev, ABS_MT_POSITION_X, x);
306 		input_report_abs(dev, ABS_MT_POSITION_Y, y);
307 	}
308 }
309 
310 /* x1 < x2 and y1 < y2 when two fingers, x = y = 0 when not pressed */
311 static void elantech_report_semi_mt_data(struct input_dev *dev,
312 					 unsigned int num_fingers,
313 					 unsigned int x1, unsigned int y1,
314 					 unsigned int x2, unsigned int y2)
315 {
316 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
317 	elantech_set_slot(dev, 1, num_fingers >= 2, x2, y2);
318 }
319 
320 /*
321  * Interpret complete data packets and report absolute mode input events for
322  * hardware version 2. (6 byte packets)
323  */
324 static void elantech_report_absolute_v2(struct psmouse *psmouse)
325 {
326 	struct elantech_data *etd = psmouse->private;
327 	struct input_dev *dev = psmouse->dev;
328 	unsigned char *packet = psmouse->packet;
329 	unsigned int fingers, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
330 	unsigned int width = 0, pres = 0;
331 
332 	/* byte 0: n1  n0   .   .   .   .   R   L */
333 	fingers = (packet[0] & 0xc0) >> 6;
334 
335 	switch (fingers) {
336 	case 3:
337 		/*
338 		 * Same as one finger, except report of more than 3 fingers:
339 		 * byte 3:  n4  .   w1  w0   .   .   .   .
340 		 */
341 		if (packet[3] & 0x80)
342 			fingers = 4;
343 		/* fall through */
344 	case 1:
345 		/*
346 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
347 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
348 		 */
349 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
350 		/*
351 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
352 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
353 		 */
354 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
355 
356 		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
357 		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
358 		break;
359 
360 	case 2:
361 		/*
362 		 * The coordinate of each finger is reported separately
363 		 * with a lower resolution for two finger touches:
364 		 * byte 0:  .   .  ay8 ax8  .   .   .   .
365 		 * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
366 		 */
367 		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
368 		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
369 		y1 = etd->y_max -
370 			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
371 		/*
372 		 * byte 3:  .   .  by8 bx8  .   .   .   .
373 		 * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
374 		 */
375 		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
376 		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
377 		y2 = etd->y_max -
378 			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
379 
380 		/* Unknown so just report sensible values */
381 		pres = 127;
382 		width = 7;
383 		break;
384 	}
385 
386 	input_report_key(dev, BTN_TOUCH, fingers != 0);
387 	if (fingers != 0) {
388 		input_report_abs(dev, ABS_X, x1);
389 		input_report_abs(dev, ABS_Y, y1);
390 	}
391 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
392 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
393 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
394 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
395 	input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);
396 	psmouse_report_standard_buttons(dev, packet[0]);
397 	if (etd->info.reports_pressure) {
398 		input_report_abs(dev, ABS_PRESSURE, pres);
399 		input_report_abs(dev, ABS_TOOL_WIDTH, width);
400 	}
401 
402 	input_sync(dev);
403 }
404 
405 static void elantech_report_trackpoint(struct psmouse *psmouse,
406 				       int packet_type)
407 {
408 	/*
409 	 * byte 0:  0   0  sx  sy   0   M   R   L
410 	 * byte 1:~sx   0   0   0   0   0   0   0
411 	 * byte 2:~sy   0   0   0   0   0   0   0
412 	 * byte 3:  0   0 ~sy ~sx   0   1   1   0
413 	 * byte 4: x7  x6  x5  x4  x3  x2  x1  x0
414 	 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
415 	 *
416 	 * x and y are written in two's complement spread
417 	 * over 9 bits with sx/sy the relative top bit and
418 	 * x7..x0 and y7..y0 the lower bits.
419 	 * The sign of y is opposite to what the input driver
420 	 * expects for a relative movement
421 	 */
422 
423 	struct elantech_data *etd = psmouse->private;
424 	struct input_dev *tp_dev = etd->tp_dev;
425 	unsigned char *packet = psmouse->packet;
426 	int x, y;
427 	u32 t;
428 
429 	t = get_unaligned_le32(&packet[0]);
430 
431 	switch (t & ~7U) {
432 	case 0x06000030U:
433 	case 0x16008020U:
434 	case 0x26800010U:
435 	case 0x36808000U:
436 		x = packet[4] - (int)((packet[1]^0x80) << 1);
437 		y = (int)((packet[2]^0x80) << 1) - packet[5];
438 
439 		psmouse_report_standard_buttons(tp_dev, packet[0]);
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->info.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->info.fw_version & 0x001000)
530 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
531 	else
532 		psmouse_report_standard_buttons(dev, packet[0]);
533 
534 	input_report_abs(dev, ABS_PRESSURE, pres);
535 	input_report_abs(dev, ABS_TOOL_WIDTH, width);
536 
537 	input_sync(dev);
538 }
539 
540 static void elantech_input_sync_v4(struct psmouse *psmouse)
541 {
542 	struct input_dev *dev = psmouse->dev;
543 	struct elantech_data *etd = psmouse->private;
544 	unsigned char *packet = psmouse->packet;
545 
546 	/* For clickpads map both buttons to BTN_LEFT */
547 	if (etd->info.fw_version & 0x001000)
548 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
549 	else
550 		psmouse_report_standard_buttons(dev, packet[0]);
551 
552 	input_mt_report_pointer_emulation(dev, true);
553 	input_sync(dev);
554 }
555 
556 static void process_packet_status_v4(struct psmouse *psmouse)
557 {
558 	struct input_dev *dev = psmouse->dev;
559 	unsigned char *packet = psmouse->packet;
560 	unsigned fingers;
561 	int i;
562 
563 	/* notify finger state change */
564 	fingers = packet[1] & 0x1f;
565 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
566 		if ((fingers & (1 << i)) == 0) {
567 			input_mt_slot(dev, i);
568 			input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
569 		}
570 	}
571 
572 	elantech_input_sync_v4(psmouse);
573 }
574 
575 static void process_packet_head_v4(struct psmouse *psmouse)
576 {
577 	struct input_dev *dev = psmouse->dev;
578 	struct elantech_data *etd = psmouse->private;
579 	unsigned char *packet = psmouse->packet;
580 	int id = ((packet[3] & 0xe0) >> 5) - 1;
581 	int pres, traces;
582 
583 	if (id < 0)
584 		return;
585 
586 	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
587 	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
588 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
589 	traces = (packet[0] & 0xf0) >> 4;
590 
591 	input_mt_slot(dev, id);
592 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
593 
594 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
595 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
596 	input_report_abs(dev, ABS_MT_PRESSURE, pres);
597 	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, traces * etd->width);
598 	/* report this for backwards compatibility */
599 	input_report_abs(dev, ABS_TOOL_WIDTH, traces);
600 
601 	elantech_input_sync_v4(psmouse);
602 }
603 
604 static void process_packet_motion_v4(struct psmouse *psmouse)
605 {
606 	struct input_dev *dev = psmouse->dev;
607 	struct elantech_data *etd = psmouse->private;
608 	unsigned char *packet = psmouse->packet;
609 	int weight, delta_x1 = 0, delta_y1 = 0, delta_x2 = 0, delta_y2 = 0;
610 	int id, sid;
611 
612 	id = ((packet[0] & 0xe0) >> 5) - 1;
613 	if (id < 0)
614 		return;
615 
616 	sid = ((packet[3] & 0xe0) >> 5) - 1;
617 	weight = (packet[0] & 0x10) ? ETP_WEIGHT_VALUE : 1;
618 	/*
619 	 * Motion packets give us the delta of x, y values of specific fingers,
620 	 * but in two's complement. Let the compiler do the conversion for us.
621 	 * Also _enlarge_ the numbers to int, in case of overflow.
622 	 */
623 	delta_x1 = (signed char)packet[1];
624 	delta_y1 = (signed char)packet[2];
625 	delta_x2 = (signed char)packet[4];
626 	delta_y2 = (signed char)packet[5];
627 
628 	etd->mt[id].x += delta_x1 * weight;
629 	etd->mt[id].y -= delta_y1 * weight;
630 	input_mt_slot(dev, id);
631 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
632 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
633 
634 	if (sid >= 0) {
635 		etd->mt[sid].x += delta_x2 * weight;
636 		etd->mt[sid].y -= delta_y2 * weight;
637 		input_mt_slot(dev, sid);
638 		input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[sid].x);
639 		input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[sid].y);
640 	}
641 
642 	elantech_input_sync_v4(psmouse);
643 }
644 
645 static void elantech_report_absolute_v4(struct psmouse *psmouse,
646 					int packet_type)
647 {
648 	switch (packet_type) {
649 	case PACKET_V4_STATUS:
650 		process_packet_status_v4(psmouse);
651 		break;
652 
653 	case PACKET_V4_HEAD:
654 		process_packet_head_v4(psmouse);
655 		break;
656 
657 	case PACKET_V4_MOTION:
658 		process_packet_motion_v4(psmouse);
659 		break;
660 
661 	case PACKET_UNKNOWN:
662 	default:
663 		/* impossible to get here */
664 		break;
665 	}
666 }
667 
668 static int elantech_packet_check_v1(struct psmouse *psmouse)
669 {
670 	struct elantech_data *etd = psmouse->private;
671 	unsigned char *packet = psmouse->packet;
672 	unsigned char p1, p2, p3;
673 
674 	/* Parity bits are placed differently */
675 	if (etd->info.fw_version < 0x020000) {
676 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
677 		p1 = (packet[0] & 0x20) >> 5;
678 		p2 = (packet[0] & 0x10) >> 4;
679 	} else {
680 		/* byte 0: n1  n0  p2  p1   1  p3   R   L */
681 		p1 = (packet[0] & 0x10) >> 4;
682 		p2 = (packet[0] & 0x20) >> 5;
683 	}
684 
685 	p3 = (packet[0] & 0x04) >> 2;
686 
687 	return etd->parity[packet[1]] == p1 &&
688 	       etd->parity[packet[2]] == p2 &&
689 	       etd->parity[packet[3]] == p3;
690 }
691 
692 static int elantech_debounce_check_v2(struct psmouse *psmouse)
693 {
694         /*
695          * When we encounter packet that matches this exactly, it means the
696          * hardware is in debounce status. Just ignore the whole packet.
697          */
698 	static const u8 debounce_packet[] = {
699 		0x84, 0xff, 0xff, 0x02, 0xff, 0xff
700 	};
701         unsigned char *packet = psmouse->packet;
702 
703         return !memcmp(packet, debounce_packet, sizeof(debounce_packet));
704 }
705 
706 static int elantech_packet_check_v2(struct psmouse *psmouse)
707 {
708 	struct elantech_data *etd = psmouse->private;
709 	unsigned char *packet = psmouse->packet;
710 
711 	/*
712 	 * V2 hardware has two flavors. Older ones that do not report pressure,
713 	 * and newer ones that reports pressure and width. With newer ones, all
714 	 * packets (1, 2, 3 finger touch) have the same constant bits. With
715 	 * older ones, 1/3 finger touch packets and 2 finger touch packets
716 	 * have different constant bits.
717 	 * With all three cases, if the constant bits are not exactly what I
718 	 * expected, I consider them invalid.
719 	 */
720 	if (etd->info.reports_pressure)
721 		return (packet[0] & 0x0c) == 0x04 &&
722 		       (packet[3] & 0x0f) == 0x02;
723 
724 	if ((packet[0] & 0xc0) == 0x80)
725 		return (packet[0] & 0x0c) == 0x0c &&
726 		       (packet[3] & 0x0e) == 0x08;
727 
728 	return (packet[0] & 0x3c) == 0x3c &&
729 	       (packet[1] & 0xf0) == 0x00 &&
730 	       (packet[3] & 0x3e) == 0x38 &&
731 	       (packet[4] & 0xf0) == 0x00;
732 }
733 
734 /*
735  * We check the constant bits to determine what packet type we get,
736  * so packet checking is mandatory for v3 and later hardware.
737  */
738 static int elantech_packet_check_v3(struct psmouse *psmouse)
739 {
740 	struct elantech_data *etd = psmouse->private;
741 	static const u8 debounce_packet[] = {
742 		0xc4, 0xff, 0xff, 0x02, 0xff, 0xff
743 	};
744 	unsigned char *packet = psmouse->packet;
745 
746 	/*
747 	 * check debounce first, it has the same signature in byte 0
748 	 * and byte 3 as PACKET_V3_HEAD.
749 	 */
750 	if (!memcmp(packet, debounce_packet, sizeof(debounce_packet)))
751 		return PACKET_DEBOUNCE;
752 
753 	/*
754 	 * If the hardware flag 'crc_enabled' is set the packets have
755 	 * different signatures.
756 	 */
757 	if (etd->info.crc_enabled) {
758 		if ((packet[3] & 0x09) == 0x08)
759 			return PACKET_V3_HEAD;
760 
761 		if ((packet[3] & 0x09) == 0x09)
762 			return PACKET_V3_TAIL;
763 	} else {
764 		if ((packet[0] & 0x0c) == 0x04 && (packet[3] & 0xcf) == 0x02)
765 			return PACKET_V3_HEAD;
766 
767 		if ((packet[0] & 0x0c) == 0x0c && (packet[3] & 0xce) == 0x0c)
768 			return PACKET_V3_TAIL;
769 		if ((packet[3] & 0x0f) == 0x06)
770 			return PACKET_TRACKPOINT;
771 	}
772 
773 	return PACKET_UNKNOWN;
774 }
775 
776 static int elantech_packet_check_v4(struct psmouse *psmouse)
777 {
778 	struct elantech_data *etd = psmouse->private;
779 	unsigned char *packet = psmouse->packet;
780 	unsigned char packet_type = packet[3] & 0x03;
781 	unsigned int ic_version;
782 	bool sanity_check;
783 
784 	if (etd->tp_dev && (packet[3] & 0x0f) == 0x06)
785 		return PACKET_TRACKPOINT;
786 
787 	/* This represents the version of IC body. */
788 	ic_version = (etd->info.fw_version & 0x0f0000) >> 16;
789 
790 	/*
791 	 * Sanity check based on the constant bits of a packet.
792 	 * The constant bits change depending on the value of
793 	 * the hardware flag 'crc_enabled' and the version of
794 	 * the IC body, but are the same for every packet,
795 	 * regardless of the type.
796 	 */
797 	if (etd->info.crc_enabled)
798 		sanity_check = ((packet[3] & 0x08) == 0x00);
799 	else if (ic_version == 7 && etd->info.samples[1] == 0x2A)
800 		sanity_check = ((packet[3] & 0x1c) == 0x10);
801 	else
802 		sanity_check = ((packet[0] & 0x08) == 0x00 &&
803 				(packet[3] & 0x1c) == 0x10);
804 
805 	if (!sanity_check)
806 		return PACKET_UNKNOWN;
807 
808 	switch (packet_type) {
809 	case 0:
810 		return PACKET_V4_STATUS;
811 
812 	case 1:
813 		return PACKET_V4_HEAD;
814 
815 	case 2:
816 		return PACKET_V4_MOTION;
817 	}
818 
819 	return PACKET_UNKNOWN;
820 }
821 
822 /*
823  * Process byte stream from mouse and handle complete packets
824  */
825 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
826 {
827 	struct elantech_data *etd = psmouse->private;
828 	int packet_type;
829 
830 	if (psmouse->pktcnt < psmouse->pktsize)
831 		return PSMOUSE_GOOD_DATA;
832 
833 	if (etd->info.debug > 1)
834 		elantech_packet_dump(psmouse);
835 
836 	switch (etd->info.hw_version) {
837 	case 1:
838 		if (etd->info.paritycheck && !elantech_packet_check_v1(psmouse))
839 			return PSMOUSE_BAD_DATA;
840 
841 		elantech_report_absolute_v1(psmouse);
842 		break;
843 
844 	case 2:
845 		/* ignore debounce */
846 		if (elantech_debounce_check_v2(psmouse))
847 			return PSMOUSE_FULL_PACKET;
848 
849 		if (etd->info.paritycheck && !elantech_packet_check_v2(psmouse))
850 			return PSMOUSE_BAD_DATA;
851 
852 		elantech_report_absolute_v2(psmouse);
853 		break;
854 
855 	case 3:
856 		packet_type = elantech_packet_check_v3(psmouse);
857 		switch (packet_type) {
858 		case PACKET_UNKNOWN:
859 			return PSMOUSE_BAD_DATA;
860 
861 		case PACKET_DEBOUNCE:
862 			/* ignore debounce */
863 			break;
864 
865 		case PACKET_TRACKPOINT:
866 			elantech_report_trackpoint(psmouse, packet_type);
867 			break;
868 
869 		default:
870 			elantech_report_absolute_v3(psmouse, packet_type);
871 			break;
872 		}
873 
874 		break;
875 
876 	case 4:
877 		packet_type = elantech_packet_check_v4(psmouse);
878 		switch (packet_type) {
879 		case PACKET_UNKNOWN:
880 			return PSMOUSE_BAD_DATA;
881 
882 		case PACKET_TRACKPOINT:
883 			elantech_report_trackpoint(psmouse, packet_type);
884 			break;
885 
886 		default:
887 			elantech_report_absolute_v4(psmouse, packet_type);
888 			break;
889 		}
890 
891 		break;
892 	}
893 
894 	return PSMOUSE_FULL_PACKET;
895 }
896 
897 /*
898  * This writes the reg_07 value again to the hardware at the end of every
899  * set_rate call because the register loses its value. reg_07 allows setting
900  * absolute mode on v4 hardware
901  */
902 static void elantech_set_rate_restore_reg_07(struct psmouse *psmouse,
903 		unsigned int rate)
904 {
905 	struct elantech_data *etd = psmouse->private;
906 
907 	etd->original_set_rate(psmouse, rate);
908 	if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
909 		psmouse_err(psmouse, "restoring reg_07 failed\n");
910 }
911 
912 /*
913  * Put the touchpad into absolute mode
914  */
915 static int elantech_set_absolute_mode(struct psmouse *psmouse)
916 {
917 	struct elantech_data *etd = psmouse->private;
918 	unsigned char val;
919 	int tries = ETP_READ_BACK_TRIES;
920 	int rc = 0;
921 
922 	switch (etd->info.hw_version) {
923 	case 1:
924 		etd->reg_10 = 0x16;
925 		etd->reg_11 = 0x8f;
926 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
927 		    elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
928 			rc = -1;
929 		}
930 		break;
931 
932 	case 2:
933 					/* Windows driver values */
934 		etd->reg_10 = 0x54;
935 		etd->reg_11 = 0x88;	/* 0x8a */
936 		etd->reg_21 = 0x60;	/* 0x00 */
937 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
938 		    elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
939 		    elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
940 			rc = -1;
941 		}
942 		break;
943 
944 	case 3:
945 		if (etd->info.set_hw_resolution)
946 			etd->reg_10 = 0x0b;
947 		else
948 			etd->reg_10 = 0x01;
949 
950 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10))
951 			rc = -1;
952 
953 		break;
954 
955 	case 4:
956 		etd->reg_07 = 0x01;
957 		if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
958 			rc = -1;
959 
960 		goto skip_readback_reg_10; /* v4 has no reg 0x10 to read */
961 	}
962 
963 	if (rc == 0) {
964 		/*
965 		 * Read back reg 0x10. For hardware version 1 we must make
966 		 * sure the absolute mode bit is set. For hardware version 2
967 		 * the touchpad is probably initializing and not ready until
968 		 * we read back the value we just wrote.
969 		 */
970 		do {
971 			rc = elantech_read_reg(psmouse, 0x10, &val);
972 			if (rc == 0)
973 				break;
974 			tries--;
975 			elantech_debug("retrying read (%d).\n", tries);
976 			msleep(ETP_READ_BACK_DELAY);
977 		} while (tries > 0);
978 
979 		if (rc) {
980 			psmouse_err(psmouse,
981 				    "failed to read back register 0x10.\n");
982 		} else if (etd->info.hw_version == 1 &&
983 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
984 			psmouse_err(psmouse,
985 				    "touchpad refuses to switch to absolute mode.\n");
986 			rc = -1;
987 		}
988 	}
989 
990  skip_readback_reg_10:
991 	if (rc)
992 		psmouse_err(psmouse, "failed to initialise registers.\n");
993 
994 	return rc;
995 }
996 
997 static int elantech_set_range(struct psmouse *psmouse,
998 			      unsigned int *x_min, unsigned int *y_min,
999 			      unsigned int *x_max, unsigned int *y_max,
1000 			      unsigned int *width)
1001 {
1002 	struct elantech_data *etd = psmouse->private;
1003 	struct elantech_device_info *info = &etd->info;
1004 	unsigned char param[3];
1005 	unsigned char traces;
1006 
1007 	switch (info->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 (info->fw_version == 0x020800 ||
1017 		    info->fw_version == 0x020b00 ||
1018 		    info->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 = (info->fw_version > 0x020800 &&
1028 			     info->fw_version < 0x020900) ? 1 : 2;
1029 
1030 			if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1031 				return -1;
1032 
1033 			fixed_dpi = param[1] & 0x10;
1034 
1035 			if (((info->fw_version >> 16) == 0x14) && fixed_dpi) {
1036 				if (info->send_cmd(psmouse, ETP_SAMPLE_QUERY, param))
1037 					return -1;
1038 
1039 				*x_max = (info->capabilities[1] - i) * param[1] / 2;
1040 				*y_max = (info->capabilities[2] - i) * param[2] / 2;
1041 			} else if (info->fw_version == 0x040216) {
1042 				*x_max = 819;
1043 				*y_max = 405;
1044 			} else if (info->fw_version == 0x040219 || info->fw_version == 0x040215) {
1045 				*x_max = 900;
1046 				*y_max = 500;
1047 			} else {
1048 				*x_max = (info->capabilities[1] - i) * 64;
1049 				*y_max = (info->capabilities[2] - i) * 64;
1050 			}
1051 		}
1052 		break;
1053 
1054 	case 3:
1055 		if (info->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 (info->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 = info->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 				      unsigned int *bus)
1092 {
1093 	unsigned char param[3];
1094 
1095 	if (elantech_send_cmd(psmouse, ETP_RESOLUTION_QUERY, param))
1096 		return -1;
1097 
1098 	*x_res = elantech_convert_res(param[1] & 0x0f);
1099 	*y_res = elantech_convert_res((param[1] & 0xf0) >> 4);
1100 	*bus = param[2];
1101 
1102 	return 0;
1103 }
1104 
1105 /*
1106  * Advertise INPUT_PROP_BUTTONPAD for clickpads. The testing of bit 12 in
1107  * fw_version for this is based on the following fw_version & caps table:
1108  *
1109  * Laptop-model:           fw_version:     caps:           buttons:
1110  * Acer S3                 0x461f00        10, 13, 0e      clickpad
1111  * Acer S7-392             0x581f01        50, 17, 0d      clickpad
1112  * Acer V5-131             0x461f02        01, 16, 0c      clickpad
1113  * Acer V5-551             0x461f00        ?               clickpad
1114  * Asus K53SV              0x450f01        78, 15, 0c      2 hw buttons
1115  * Asus G46VW              0x460f02        00, 18, 0c      2 hw buttons
1116  * Asus G750JX             0x360f00        00, 16, 0c      2 hw buttons
1117  * Asus TP500LN            0x381f17        10, 14, 0e      clickpad
1118  * Asus X750JN             0x381f17        10, 14, 0e      clickpad
1119  * Asus UX31               0x361f00        20, 15, 0e      clickpad
1120  * Asus UX32VD             0x361f02        00, 15, 0e      clickpad
1121  * Avatar AVIU-145A2       0x361f00        ?               clickpad
1122  * Fujitsu LIFEBOOK E544   0x470f00        d0, 12, 09      2 hw buttons
1123  * Fujitsu LIFEBOOK E546   0x470f00        50, 12, 09      2 hw buttons
1124  * Fujitsu LIFEBOOK E547   0x470f00        50, 12, 09      2 hw buttons
1125  * Fujitsu LIFEBOOK E554   0x570f01        40, 14, 0c      2 hw buttons
1126  * Fujitsu LIFEBOOK E557   0x570f01        40, 14, 0c      2 hw buttons
1127  * Fujitsu T725            0x470f01        05, 12, 09      2 hw buttons
1128  * Fujitsu H730            0x570f00        c0, 14, 0c      3 hw buttons (**)
1129  * Gigabyte U2442          0x450f01        58, 17, 0c      2 hw buttons
1130  * Lenovo L430             0x350f02        b9, 15, 0c      2 hw buttons (*)
1131  * Lenovo L530             0x350f02        b9, 15, 0c      2 hw buttons (*)
1132  * Samsung NF210           0x150b00        78, 14, 0a      2 hw buttons
1133  * Samsung NP770Z5E        0x575f01        10, 15, 0f      clickpad
1134  * Samsung NP700Z5B        0x361f06        21, 15, 0f      clickpad
1135  * Samsung NP900X3E-A02    0x575f03        ?               clickpad
1136  * Samsung NP-QX410        0x851b00        19, 14, 0c      clickpad
1137  * Samsung RC512           0x450f00        08, 15, 0c      2 hw buttons
1138  * Samsung RF710           0x450f00        ?               2 hw buttons
1139  * System76 Pangolin       0x250f01        ?               2 hw buttons
1140  * (*) + 3 trackpoint buttons
1141  * (**) + 0 trackpoint buttons
1142  * Note: Lenovo L430 and Lenovo L530 have the same fw_version/caps
1143  */
1144 static void elantech_set_buttonpad_prop(struct psmouse *psmouse)
1145 {
1146 	struct input_dev *dev = psmouse->dev;
1147 	struct elantech_data *etd = psmouse->private;
1148 
1149 	if (etd->info.fw_version & 0x001000) {
1150 		__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
1151 		__clear_bit(BTN_RIGHT, dev->keybit);
1152 	}
1153 }
1154 
1155 /*
1156  * Some hw_version 4 models do have a middle button
1157  */
1158 static const struct dmi_system_id elantech_dmi_has_middle_button[] = {
1159 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1160 	{
1161 		/* Fujitsu H730 has a middle button */
1162 		.matches = {
1163 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1164 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1165 		},
1166 	},
1167 	{
1168 		/* Fujitsu H760 also has a middle button */
1169 		.matches = {
1170 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1171 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1172 		},
1173 	},
1174 #endif
1175 	{ }
1176 };
1177 
1178 static const char * const middle_button_pnp_ids[] = {
1179 	"LEN2131", /* ThinkPad P52 w/ NFC */
1180 	"LEN2132", /* ThinkPad P52 */
1181 	"LEN2133", /* ThinkPad P72 w/ NFC */
1182 	"LEN2134", /* ThinkPad P72 */
1183 	NULL
1184 };
1185 
1186 /*
1187  * Set the appropriate event bits for the input subsystem
1188  */
1189 static int elantech_set_input_params(struct psmouse *psmouse)
1190 {
1191 	struct input_dev *dev = psmouse->dev;
1192 	struct elantech_data *etd = psmouse->private;
1193 	struct elantech_device_info *info = &etd->info;
1194 	unsigned int x_min = 0, y_min = 0, x_max = 0, y_max = 0, width = 0;
1195 
1196 	if (elantech_set_range(psmouse, &x_min, &y_min, &x_max, &y_max, &width))
1197 		return -1;
1198 
1199 	__set_bit(INPUT_PROP_POINTER, dev->propbit);
1200 	__set_bit(EV_KEY, dev->evbit);
1201 	__set_bit(EV_ABS, dev->evbit);
1202 	__clear_bit(EV_REL, dev->evbit);
1203 
1204 	__set_bit(BTN_LEFT, dev->keybit);
1205 	if (dmi_check_system(elantech_dmi_has_middle_button) ||
1206 			psmouse_matches_pnp_id(psmouse, middle_button_pnp_ids))
1207 		__set_bit(BTN_MIDDLE, dev->keybit);
1208 	__set_bit(BTN_RIGHT, dev->keybit);
1209 
1210 	__set_bit(BTN_TOUCH, dev->keybit);
1211 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
1212 	__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
1213 	__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
1214 
1215 	switch (info->hw_version) {
1216 	case 1:
1217 		/* Rocker button */
1218 		if (info->fw_version < 0x020000 &&
1219 		    (info->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
1220 			__set_bit(BTN_FORWARD, dev->keybit);
1221 			__set_bit(BTN_BACK, dev->keybit);
1222 		}
1223 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1224 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1225 		break;
1226 
1227 	case 2:
1228 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1229 		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
1230 		/* fall through */
1231 	case 3:
1232 		if (info->hw_version == 3)
1233 			elantech_set_buttonpad_prop(psmouse);
1234 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1235 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1236 		if (info->reports_pressure) {
1237 			input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1238 					     ETP_PMAX_V2, 0, 0);
1239 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1240 					     ETP_WMAX_V2, 0, 0);
1241 		}
1242 		input_mt_init_slots(dev, 2, INPUT_MT_SEMI_MT);
1243 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1244 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1245 		break;
1246 
1247 	case 4:
1248 		elantech_set_buttonpad_prop(psmouse);
1249 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1250 		/* For X to recognize me as touchpad. */
1251 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1252 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1253 		/*
1254 		 * range of pressure and width is the same as v2,
1255 		 * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
1256 		 */
1257 		input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1258 				     ETP_PMAX_V2, 0, 0);
1259 		input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1260 				     ETP_WMAX_V2, 0, 0);
1261 		/* Multitouch capable pad, up to 5 fingers. */
1262 		input_mt_init_slots(dev, ETP_MAX_FINGERS, 0);
1263 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1264 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1265 		input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
1266 				     ETP_PMAX_V2, 0, 0);
1267 		/*
1268 		 * The firmware reports how many trace lines the finger spans,
1269 		 * convert to surface unit as Protocol-B requires.
1270 		 */
1271 		input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 0,
1272 				     ETP_WMAX_V2 * width, 0, 0);
1273 		break;
1274 	}
1275 
1276 	input_abs_set_res(dev, ABS_X, info->x_res);
1277 	input_abs_set_res(dev, ABS_Y, info->y_res);
1278 	if (info->hw_version > 1) {
1279 		input_abs_set_res(dev, ABS_MT_POSITION_X, info->x_res);
1280 		input_abs_set_res(dev, ABS_MT_POSITION_Y, info->y_res);
1281 	}
1282 
1283 	etd->y_max = y_max;
1284 	etd->width = width;
1285 
1286 	return 0;
1287 }
1288 
1289 struct elantech_attr_data {
1290 	size_t		field_offset;
1291 	unsigned char	reg;
1292 };
1293 
1294 /*
1295  * Display a register value by reading a sysfs entry
1296  */
1297 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
1298 					char *buf)
1299 {
1300 	struct elantech_data *etd = psmouse->private;
1301 	struct elantech_attr_data *attr = data;
1302 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1303 	int rc = 0;
1304 
1305 	if (attr->reg)
1306 		rc = elantech_read_reg(psmouse, attr->reg, reg);
1307 
1308 	return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
1309 }
1310 
1311 /*
1312  * Write a register value by writing a sysfs entry
1313  */
1314 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
1315 				     void *data, const char *buf, size_t count)
1316 {
1317 	struct elantech_data *etd = psmouse->private;
1318 	struct elantech_attr_data *attr = data;
1319 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1320 	unsigned char value;
1321 	int err;
1322 
1323 	err = kstrtou8(buf, 16, &value);
1324 	if (err)
1325 		return err;
1326 
1327 	/* Do we need to preserve some bits for version 2 hardware too? */
1328 	if (etd->info.hw_version == 1) {
1329 		if (attr->reg == 0x10)
1330 			/* Force absolute mode always on */
1331 			value |= ETP_R10_ABSOLUTE_MODE;
1332 		else if (attr->reg == 0x11)
1333 			/* Force 4 byte mode always on */
1334 			value |= ETP_R11_4_BYTE_MODE;
1335 	}
1336 
1337 	if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
1338 		*reg = value;
1339 
1340 	return count;
1341 }
1342 
1343 #define ELANTECH_INT_ATTR(_name, _register)				\
1344 	static struct elantech_attr_data elantech_attr_##_name = {	\
1345 		.field_offset = offsetof(struct elantech_data, _name),	\
1346 		.reg = _register,					\
1347 	};								\
1348 	PSMOUSE_DEFINE_ATTR(_name, 0644,				\
1349 			    &elantech_attr_##_name,			\
1350 			    elantech_show_int_attr,			\
1351 			    elantech_set_int_attr)
1352 
1353 #define ELANTECH_INFO_ATTR(_name)					       \
1354 	static struct elantech_attr_data elantech_attr_##_name = {	       \
1355 		.field_offset = offsetof(struct elantech_data, info) +	       \
1356 				offsetof(struct elantech_device_info, _name),  \
1357 		.reg = 0,						       \
1358 	};								       \
1359 	PSMOUSE_DEFINE_ATTR(_name, 0644,				       \
1360 			    &elantech_attr_##_name,			       \
1361 			    elantech_show_int_attr,			       \
1362 			    elantech_set_int_attr)
1363 
1364 ELANTECH_INT_ATTR(reg_07, 0x07);
1365 ELANTECH_INT_ATTR(reg_10, 0x10);
1366 ELANTECH_INT_ATTR(reg_11, 0x11);
1367 ELANTECH_INT_ATTR(reg_20, 0x20);
1368 ELANTECH_INT_ATTR(reg_21, 0x21);
1369 ELANTECH_INT_ATTR(reg_22, 0x22);
1370 ELANTECH_INT_ATTR(reg_23, 0x23);
1371 ELANTECH_INT_ATTR(reg_24, 0x24);
1372 ELANTECH_INT_ATTR(reg_25, 0x25);
1373 ELANTECH_INT_ATTR(reg_26, 0x26);
1374 ELANTECH_INFO_ATTR(debug);
1375 ELANTECH_INFO_ATTR(paritycheck);
1376 ELANTECH_INFO_ATTR(crc_enabled);
1377 
1378 static struct attribute *elantech_attrs[] = {
1379 	&psmouse_attr_reg_07.dattr.attr,
1380 	&psmouse_attr_reg_10.dattr.attr,
1381 	&psmouse_attr_reg_11.dattr.attr,
1382 	&psmouse_attr_reg_20.dattr.attr,
1383 	&psmouse_attr_reg_21.dattr.attr,
1384 	&psmouse_attr_reg_22.dattr.attr,
1385 	&psmouse_attr_reg_23.dattr.attr,
1386 	&psmouse_attr_reg_24.dattr.attr,
1387 	&psmouse_attr_reg_25.dattr.attr,
1388 	&psmouse_attr_reg_26.dattr.attr,
1389 	&psmouse_attr_debug.dattr.attr,
1390 	&psmouse_attr_paritycheck.dattr.attr,
1391 	&psmouse_attr_crc_enabled.dattr.attr,
1392 	NULL
1393 };
1394 
1395 static const struct attribute_group elantech_attr_group = {
1396 	.attrs = elantech_attrs,
1397 };
1398 
1399 static bool elantech_is_signature_valid(const unsigned char *param)
1400 {
1401 	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
1402 	int i;
1403 
1404 	if (param[0] == 0)
1405 		return false;
1406 
1407 	if (param[1] == 0)
1408 		return true;
1409 
1410 	/*
1411 	 * Some hw_version >= 4 models have a revision higher then 20. Meaning
1412 	 * that param[2] may be 10 or 20, skip the rates check for these.
1413 	 */
1414 	if ((param[0] & 0x0f) >= 0x06 && (param[1] & 0xaf) == 0x0f &&
1415 	    param[2] < 40)
1416 		return true;
1417 
1418 	for (i = 0; i < ARRAY_SIZE(rates); i++)
1419 		if (param[2] == rates[i])
1420 			return false;
1421 
1422 	return true;
1423 }
1424 
1425 /*
1426  * Use magic knock to detect Elantech touchpad
1427  */
1428 int elantech_detect(struct psmouse *psmouse, bool set_properties)
1429 {
1430 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1431 	unsigned char param[3];
1432 
1433 	ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1434 
1435 	if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
1436 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1437 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1438 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1439 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1440 		psmouse_dbg(psmouse, "sending Elantech magic knock failed.\n");
1441 		return -1;
1442 	}
1443 
1444 	/*
1445 	 * Report this in case there are Elantech models that use a different
1446 	 * set of magic numbers
1447 	 */
1448 	if (param[0] != 0x3c || param[1] != 0x03 ||
1449 	    (param[2] != 0xc8 && param[2] != 0x00)) {
1450 		psmouse_dbg(psmouse,
1451 			    "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
1452 			    param[0], param[1], param[2]);
1453 		return -1;
1454 	}
1455 
1456 	/*
1457 	 * Query touchpad's firmware version and see if it reports known
1458 	 * value to avoid mis-detection. Logitech mice are known to respond
1459 	 * to Elantech magic knock and there might be more.
1460 	 */
1461 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1462 		psmouse_dbg(psmouse, "failed to query firmware version.\n");
1463 		return -1;
1464 	}
1465 
1466 	psmouse_dbg(psmouse,
1467 		    "Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
1468 		    param[0], param[1], param[2]);
1469 
1470 	if (!elantech_is_signature_valid(param)) {
1471 		psmouse_dbg(psmouse,
1472 			    "Probably not a real Elantech touchpad. Aborting.\n");
1473 		return -1;
1474 	}
1475 
1476 	if (set_properties) {
1477 		psmouse->vendor = "Elantech";
1478 		psmouse->name = "Touchpad";
1479 	}
1480 
1481 	return 0;
1482 }
1483 
1484 /*
1485  * Clean up sysfs entries when disconnecting
1486  */
1487 static void elantech_disconnect(struct psmouse *psmouse)
1488 {
1489 	struct elantech_data *etd = psmouse->private;
1490 
1491 	/*
1492 	 * We might have left a breadcrumb when trying to
1493 	 * set up SMbus companion.
1494 	 */
1495 	psmouse_smbus_cleanup(psmouse);
1496 
1497 	if (etd->tp_dev)
1498 		input_unregister_device(etd->tp_dev);
1499 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1500 			   &elantech_attr_group);
1501 	kfree(psmouse->private);
1502 	psmouse->private = NULL;
1503 }
1504 
1505 /*
1506  * Put the touchpad back into absolute mode when reconnecting
1507  */
1508 static int elantech_reconnect(struct psmouse *psmouse)
1509 {
1510 	psmouse_reset(psmouse);
1511 
1512 	if (elantech_detect(psmouse, 0))
1513 		return -1;
1514 
1515 	if (elantech_set_absolute_mode(psmouse)) {
1516 		psmouse_err(psmouse,
1517 			    "failed to put touchpad back into absolute mode.\n");
1518 		return -1;
1519 	}
1520 
1521 	return 0;
1522 }
1523 
1524 /*
1525  * Some hw_version 4 models do not work with crc_disabled
1526  */
1527 static const struct dmi_system_id elantech_dmi_force_crc_enabled[] = {
1528 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1529 	{
1530 		/* Fujitsu H730 does not work with crc_enabled == 0 */
1531 		.matches = {
1532 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1533 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1534 		},
1535 	},
1536 	{
1537 		/* Fujitsu H760 does not work with crc_enabled == 0 */
1538 		.matches = {
1539 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1540 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1541 		},
1542 	},
1543 	{
1544 		/* Fujitsu LIFEBOOK E544  does not work with crc_enabled == 0 */
1545 		.matches = {
1546 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1547 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E544"),
1548 		},
1549 	},
1550 	{
1551 		/* Fujitsu LIFEBOOK E546  does not work with crc_enabled == 0 */
1552 		.matches = {
1553 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1554 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E546"),
1555 		},
1556 	},
1557 	{
1558 		/* Fujitsu LIFEBOOK E547 does not work with crc_enabled == 0 */
1559 		.matches = {
1560 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1561 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E547"),
1562 		},
1563 	},
1564 	{
1565 		/* Fujitsu LIFEBOOK E554  does not work with crc_enabled == 0 */
1566 		.matches = {
1567 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1568 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E554"),
1569 		},
1570 	},
1571 	{
1572 		/* Fujitsu LIFEBOOK E556 does not work with crc_enabled == 0 */
1573 		.matches = {
1574 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1575 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E556"),
1576 		},
1577 	},
1578 	{
1579 		/* Fujitsu LIFEBOOK E557 does not work with crc_enabled == 0 */
1580 		.matches = {
1581 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1582 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E557"),
1583 		},
1584 	},
1585 	{
1586 		/* Fujitsu LIFEBOOK U745 does not work with crc_enabled == 0 */
1587 		.matches = {
1588 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1589 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK U745"),
1590 		},
1591 	},
1592 #endif
1593 	{ }
1594 };
1595 
1596 /*
1597  * Some hw_version 3 models go into error state when we try to set
1598  * bit 3 and/or bit 1 of r10.
1599  */
1600 static const struct dmi_system_id no_hw_res_dmi_table[] = {
1601 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1602 	{
1603 		/* Gigabyte U2442 */
1604 		.matches = {
1605 			DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
1606 			DMI_MATCH(DMI_PRODUCT_NAME, "U2442"),
1607 		},
1608 	},
1609 #endif
1610 	{ }
1611 };
1612 
1613 /*
1614  * determine hardware version and set some properties according to it.
1615  */
1616 static int elantech_set_properties(struct elantech_device_info *info)
1617 {
1618 	/* This represents the version of IC body. */
1619 	int ver = (info->fw_version & 0x0f0000) >> 16;
1620 
1621 	/* Early version of Elan touchpads doesn't obey the rule. */
1622 	if (info->fw_version < 0x020030 || info->fw_version == 0x020600)
1623 		info->hw_version = 1;
1624 	else {
1625 		switch (ver) {
1626 		case 2:
1627 		case 4:
1628 			info->hw_version = 2;
1629 			break;
1630 		case 5:
1631 			info->hw_version = 3;
1632 			break;
1633 		case 6 ... 15:
1634 			info->hw_version = 4;
1635 			break;
1636 		default:
1637 			return -1;
1638 		}
1639 	}
1640 
1641 	/* decide which send_cmd we're gonna use early */
1642 	info->send_cmd = info->hw_version >= 3 ? elantech_send_cmd :
1643 						 synaptics_send_cmd;
1644 
1645 	/* Turn on packet checking by default */
1646 	info->paritycheck = 1;
1647 
1648 	/*
1649 	 * This firmware suffers from misreporting coordinates when
1650 	 * a touch action starts causing the mouse cursor or scrolled page
1651 	 * to jump. Enable a workaround.
1652 	 */
1653 	info->jumpy_cursor =
1654 		(info->fw_version == 0x020022 || info->fw_version == 0x020600);
1655 
1656 	if (info->hw_version > 1) {
1657 		/* For now show extra debug information */
1658 		info->debug = 1;
1659 
1660 		if (info->fw_version >= 0x020800)
1661 			info->reports_pressure = true;
1662 	}
1663 
1664 	/*
1665 	 * The signatures of v3 and v4 packets change depending on the
1666 	 * value of this hardware flag.
1667 	 */
1668 	info->crc_enabled = (info->fw_version & 0x4000) == 0x4000 ||
1669 			     dmi_check_system(elantech_dmi_force_crc_enabled);
1670 
1671 	/* Enable real hardware resolution on hw_version 3 ? */
1672 	info->set_hw_resolution = !dmi_check_system(no_hw_res_dmi_table);
1673 
1674 	return 0;
1675 }
1676 
1677 static int elantech_query_info(struct psmouse *psmouse,
1678 			       struct elantech_device_info *info)
1679 {
1680 	unsigned char param[3];
1681 
1682 	memset(info, 0, sizeof(*info));
1683 
1684 	/*
1685 	 * Do the version query again so we can store the result
1686 	 */
1687 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1688 		psmouse_err(psmouse, "failed to query firmware version.\n");
1689 		return -EINVAL;
1690 	}
1691 	info->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
1692 
1693 	if (elantech_set_properties(info)) {
1694 		psmouse_err(psmouse, "unknown hardware version, aborting...\n");
1695 		return -EINVAL;
1696 	}
1697 	psmouse_info(psmouse,
1698 		     "assuming hardware version %d (with firmware version 0x%02x%02x%02x)\n",
1699 		     info->hw_version, param[0], param[1], param[2]);
1700 
1701 	if (info->send_cmd(psmouse, ETP_CAPABILITIES_QUERY,
1702 	    info->capabilities)) {
1703 		psmouse_err(psmouse, "failed to query capabilities.\n");
1704 		return -EINVAL;
1705 	}
1706 	psmouse_info(psmouse,
1707 		     "Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
1708 		     info->capabilities[0], info->capabilities[1],
1709 		     info->capabilities[2]);
1710 
1711 	if (info->hw_version != 1) {
1712 		if (info->send_cmd(psmouse, ETP_SAMPLE_QUERY, info->samples)) {
1713 			psmouse_err(psmouse, "failed to query sample data\n");
1714 			return -EINVAL;
1715 		}
1716 		psmouse_info(psmouse,
1717 			     "Elan sample query result %02x, %02x, %02x\n",
1718 			     info->samples[0],
1719 			     info->samples[1],
1720 			     info->samples[2]);
1721 	}
1722 
1723 	if (info->samples[1] == 0x74 && info->hw_version == 0x03) {
1724 		/*
1725 		 * This module has a bug which makes absolute mode
1726 		 * unusable, so let's abort so we'll be using standard
1727 		 * PS/2 protocol.
1728 		 */
1729 		psmouse_info(psmouse,
1730 			     "absolute mode broken, forcing standard PS/2 protocol\n");
1731 		return -ENODEV;
1732 	}
1733 
1734 	/* The MSB indicates the presence of the trackpoint */
1735 	info->has_trackpoint = (info->capabilities[0] & 0x80) == 0x80;
1736 
1737 	info->x_res = 31;
1738 	info->y_res = 31;
1739 	if (info->hw_version == 4) {
1740 		if (elantech_get_resolution_v4(psmouse,
1741 					       &info->x_res,
1742 					       &info->y_res,
1743 					       &info->bus)) {
1744 			psmouse_warn(psmouse,
1745 				     "failed to query resolution data.\n");
1746 		}
1747 	}
1748 
1749 	return 0;
1750 }
1751 
1752 #if defined(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)
1753 
1754 /*
1755  * The newest Elantech device can use a secondary bus (over SMBus) which
1756  * provides a better bandwidth and allow a better control of the touchpads.
1757  * This is used to decide if we need to use this bus or not.
1758  */
1759 enum {
1760 	ELANTECH_SMBUS_NOT_SET = -1,
1761 	ELANTECH_SMBUS_OFF,
1762 	ELANTECH_SMBUS_ON,
1763 };
1764 
1765 static int elantech_smbus = IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) ?
1766 		ELANTECH_SMBUS_NOT_SET : ELANTECH_SMBUS_OFF;
1767 module_param_named(elantech_smbus, elantech_smbus, int, 0644);
1768 MODULE_PARM_DESC(elantech_smbus, "Use a secondary bus for the Elantech device.");
1769 
1770 static int elantech_create_smbus(struct psmouse *psmouse,
1771 				 struct elantech_device_info *info,
1772 				 bool leave_breadcrumbs)
1773 {
1774 	const struct property_entry i2c_properties[] = {
1775 		PROPERTY_ENTRY_BOOL("elan,trackpoint"),
1776 		{ },
1777 	};
1778 	struct i2c_board_info smbus_board = {
1779 		I2C_BOARD_INFO("elan_i2c", 0x15),
1780 		.flags = I2C_CLIENT_HOST_NOTIFY,
1781 	};
1782 
1783 	if (info->has_trackpoint)
1784 		smbus_board.properties = i2c_properties;
1785 
1786 	return psmouse_smbus_init(psmouse, &smbus_board, NULL, 0, false,
1787 				  leave_breadcrumbs);
1788 }
1789 
1790 /**
1791  * elantech_setup_smbus - called once the PS/2 devices are enumerated
1792  * and decides to instantiate a SMBus InterTouch device.
1793  */
1794 static int elantech_setup_smbus(struct psmouse *psmouse,
1795 				struct elantech_device_info *info,
1796 				bool leave_breadcrumbs)
1797 {
1798 	int error;
1799 
1800 	if (elantech_smbus == ELANTECH_SMBUS_OFF)
1801 		return -ENXIO;
1802 
1803 	if (elantech_smbus == ELANTECH_SMBUS_NOT_SET) {
1804 		/*
1805 		 * New ICs are enabled by default.
1806 		 * Old ICs are up to the user to decide.
1807 		 */
1808 		if (!ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version))
1809 			return -ENXIO;
1810 	}
1811 
1812 	psmouse_info(psmouse, "Trying to set up SMBus access\n");
1813 
1814 	error = elantech_create_smbus(psmouse, info, leave_breadcrumbs);
1815 	if (error) {
1816 		if (error == -EAGAIN)
1817 			psmouse_info(psmouse, "SMbus companion is not ready yet\n");
1818 		else
1819 			psmouse_err(psmouse, "unable to create intertouch device\n");
1820 
1821 		return error;
1822 	}
1823 
1824 	return 0;
1825 }
1826 
1827 static bool elantech_use_host_notify(struct psmouse *psmouse,
1828 				     struct elantech_device_info *info)
1829 {
1830 	if (ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version))
1831 		return true;
1832 
1833 	switch (info->bus) {
1834 	case ETP_BUS_PS2_ONLY:
1835 		/* expected case */
1836 		break;
1837 	case ETP_BUS_SMB_ALERT_ONLY:
1838 		/* fall-through  */
1839 	case ETP_BUS_PS2_SMB_ALERT:
1840 		psmouse_dbg(psmouse, "Ignoring SMBus provider through alert protocol.\n");
1841 		break;
1842 	case ETP_BUS_SMB_HST_NTFY_ONLY:
1843 		/* fall-through  */
1844 	case ETP_BUS_PS2_SMB_HST_NTFY:
1845 		return true;
1846 	default:
1847 		psmouse_dbg(psmouse,
1848 			    "Ignoring SMBus bus provider %d.\n",
1849 			    info->bus);
1850 	}
1851 
1852 	return false;
1853 }
1854 
1855 int elantech_init_smbus(struct psmouse *psmouse)
1856 {
1857 	struct elantech_device_info info;
1858 	int error = -EINVAL;
1859 
1860 	psmouse_reset(psmouse);
1861 
1862 	error = elantech_query_info(psmouse, &info);
1863 	if (error)
1864 		goto init_fail;
1865 
1866 	if (info.hw_version < 4) {
1867 		error = -ENXIO;
1868 		goto init_fail;
1869 	}
1870 
1871 	return elantech_create_smbus(psmouse, &info, false);
1872  init_fail:
1873 	psmouse_reset(psmouse);
1874 	return error;
1875 }
1876 #endif /* CONFIG_MOUSE_PS2_ELANTECH_SMBUS */
1877 
1878 /*
1879  * Initialize the touchpad and create sysfs entries
1880  */
1881 static int elantech_setup_ps2(struct psmouse *psmouse,
1882 			      struct elantech_device_info *info)
1883 {
1884 	struct elantech_data *etd;
1885 	int i;
1886 	int error = -EINVAL;
1887 	struct input_dev *tp_dev;
1888 
1889 	psmouse->private = etd = kzalloc(sizeof(*etd), GFP_KERNEL);
1890 	if (!etd)
1891 		return -ENOMEM;
1892 
1893 	etd->info = *info;
1894 
1895 	etd->parity[0] = 1;
1896 	for (i = 1; i < 256; i++)
1897 		etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
1898 
1899 	if (elantech_set_absolute_mode(psmouse)) {
1900 		psmouse_err(psmouse,
1901 			    "failed to put touchpad into absolute mode.\n");
1902 		goto init_fail;
1903 	}
1904 
1905 	if (info->fw_version == 0x381f17) {
1906 		etd->original_set_rate = psmouse->set_rate;
1907 		psmouse->set_rate = elantech_set_rate_restore_reg_07;
1908 	}
1909 
1910 	if (elantech_set_input_params(psmouse)) {
1911 		psmouse_err(psmouse, "failed to query touchpad range.\n");
1912 		goto init_fail;
1913 	}
1914 
1915 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
1916 				   &elantech_attr_group);
1917 	if (error) {
1918 		psmouse_err(psmouse,
1919 			    "failed to create sysfs attributes, error: %d.\n",
1920 			    error);
1921 		goto init_fail;
1922 	}
1923 
1924 	if (info->has_trackpoint) {
1925 		tp_dev = input_allocate_device();
1926 
1927 		if (!tp_dev) {
1928 			error = -ENOMEM;
1929 			goto init_fail_tp_alloc;
1930 		}
1931 
1932 		etd->tp_dev = tp_dev;
1933 		snprintf(etd->tp_phys, sizeof(etd->tp_phys), "%s/input1",
1934 			psmouse->ps2dev.serio->phys);
1935 		tp_dev->phys = etd->tp_phys;
1936 		tp_dev->name = "ETPS/2 Elantech TrackPoint";
1937 		tp_dev->id.bustype = BUS_I8042;
1938 		tp_dev->id.vendor  = 0x0002;
1939 		tp_dev->id.product = PSMOUSE_ELANTECH;
1940 		tp_dev->id.version = 0x0000;
1941 		tp_dev->dev.parent = &psmouse->ps2dev.serio->dev;
1942 		tp_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
1943 		tp_dev->relbit[BIT_WORD(REL_X)] =
1944 			BIT_MASK(REL_X) | BIT_MASK(REL_Y);
1945 		tp_dev->keybit[BIT_WORD(BTN_LEFT)] =
1946 			BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
1947 			BIT_MASK(BTN_RIGHT);
1948 
1949 		__set_bit(INPUT_PROP_POINTER, tp_dev->propbit);
1950 		__set_bit(INPUT_PROP_POINTING_STICK, tp_dev->propbit);
1951 
1952 		error = input_register_device(etd->tp_dev);
1953 		if (error < 0)
1954 			goto init_fail_tp_reg;
1955 	}
1956 
1957 	psmouse->protocol_handler = elantech_process_byte;
1958 	psmouse->disconnect = elantech_disconnect;
1959 	psmouse->reconnect = elantech_reconnect;
1960 	psmouse->pktsize = info->hw_version > 1 ? 6 : 4;
1961 
1962 	return 0;
1963  init_fail_tp_reg:
1964 	input_free_device(tp_dev);
1965  init_fail_tp_alloc:
1966 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1967 			   &elantech_attr_group);
1968  init_fail:
1969 	kfree(etd);
1970 	return error;
1971 }
1972 
1973 int elantech_init_ps2(struct psmouse *psmouse)
1974 {
1975 	struct elantech_device_info info;
1976 	int error = -EINVAL;
1977 
1978 	psmouse_reset(psmouse);
1979 
1980 	error = elantech_query_info(psmouse, &info);
1981 	if (error)
1982 		goto init_fail;
1983 
1984 	error = elantech_setup_ps2(psmouse, &info);
1985 	if (error)
1986 		goto init_fail;
1987 
1988 	return 0;
1989  init_fail:
1990 	psmouse_reset(psmouse);
1991 	return error;
1992 }
1993 
1994 int elantech_init(struct psmouse *psmouse)
1995 {
1996 	struct elantech_device_info info;
1997 	int error = -EINVAL;
1998 
1999 	psmouse_reset(psmouse);
2000 
2001 	error = elantech_query_info(psmouse, &info);
2002 	if (error)
2003 		goto init_fail;
2004 
2005 #if defined(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)
2006 
2007 	if (elantech_use_host_notify(psmouse, &info)) {
2008 		if (!IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) ||
2009 		    !IS_ENABLED(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)) {
2010 			psmouse_warn(psmouse,
2011 				     "The touchpad can support a better bus than the too old PS/2 protocol. "
2012 				     "Make sure MOUSE_PS2_ELANTECH_SMBUS and MOUSE_ELAN_I2C_SMBUS are enabled to get a better touchpad experience.\n");
2013 		}
2014 		error = elantech_setup_smbus(psmouse, &info, true);
2015 		if (!error)
2016 			return PSMOUSE_ELANTECH_SMBUS;
2017 	}
2018 
2019 #endif /* CONFIG_MOUSE_PS2_ELANTECH_SMBUS */
2020 
2021 	error = elantech_setup_ps2(psmouse, &info);
2022 	if (error < 0) {
2023 		/*
2024 		 * Not using any flavor of Elantech support, so clean up
2025 		 * SMbus breadcrumbs, if any.
2026 		 */
2027 		psmouse_smbus_cleanup(psmouse);
2028 		goto init_fail;
2029 	}
2030 
2031 	return PSMOUSE_ELANTECH;
2032  init_fail:
2033 	psmouse_reset(psmouse);
2034 	return error;
2035 }
2036