xref: /openbmc/linux/drivers/input/mouse/elantech.c (revision 171f1bc7)
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/slab.h>
15 #include <linux/module.h>
16 #include <linux/input.h>
17 #include <linux/input/mt.h>
18 #include <linux/serio.h>
19 #include <linux/libps2.h>
20 #include "psmouse.h"
21 #include "elantech.h"
22 
23 #define elantech_debug(fmt, ...)					\
24 	do {								\
25 		if (etd->debug)						\
26 			psmouse_printk(KERN_DEBUG, psmouse,		\
27 					fmt, ##__VA_ARGS__);		\
28 	} while (0)
29 
30 /*
31  * Send a Synaptics style sliced query command
32  */
33 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
34 				unsigned char *param)
35 {
36 	if (psmouse_sliced_command(psmouse, c) ||
37 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
38 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
39 		return -1;
40 	}
41 
42 	return 0;
43 }
44 
45 /*
46  * A retrying version of ps2_command
47  */
48 static int elantech_ps2_command(struct psmouse *psmouse,
49 				unsigned char *param, int command)
50 {
51 	struct ps2dev *ps2dev = &psmouse->ps2dev;
52 	struct elantech_data *etd = psmouse->private;
53 	int rc;
54 	int tries = ETP_PS2_COMMAND_TRIES;
55 
56 	do {
57 		rc = ps2_command(ps2dev, param, command);
58 		if (rc == 0)
59 			break;
60 		tries--;
61 		elantech_debug("retrying ps2 command 0x%02x (%d).\n",
62 				command, tries);
63 		msleep(ETP_PS2_COMMAND_DELAY);
64 	} while (tries > 0);
65 
66 	if (rc)
67 		psmouse_err(psmouse, "ps2 command 0x%02x failed.\n", command);
68 
69 	return rc;
70 }
71 
72 /*
73  * Send an Elantech style special command to read a value from a register
74  */
75 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
76 				unsigned char *val)
77 {
78 	struct elantech_data *etd = psmouse->private;
79 	unsigned char param[3];
80 	int rc = 0;
81 
82 	if (reg < 0x07 || reg > 0x26)
83 		return -1;
84 
85 	if (reg > 0x11 && reg < 0x20)
86 		return -1;
87 
88 	switch (etd->hw_version) {
89 	case 1:
90 		if (psmouse_sliced_command(psmouse, ETP_REGISTER_READ) ||
91 		    psmouse_sliced_command(psmouse, reg) ||
92 		    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
93 			rc = -1;
94 		}
95 		break;
96 
97 	case 2:
98 		if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
99 		    elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
100 		    elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
101 		    elantech_ps2_command(psmouse,  NULL, reg) ||
102 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
103 			rc = -1;
104 		}
105 		break;
106 
107 	case 3 ... 4:
108 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
109 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
110 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
111 		    elantech_ps2_command(psmouse, NULL, reg) ||
112 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
113 			rc = -1;
114 		}
115 		break;
116 	}
117 
118 	if (rc)
119 		psmouse_err(psmouse, "failed to read register 0x%02x.\n", reg);
120 	else if (etd->hw_version != 4)
121 		*val = param[0];
122 	else
123 		*val = param[1];
124 
125 	return rc;
126 }
127 
128 /*
129  * Send an Elantech style special command to write a register with a value
130  */
131 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
132 				unsigned char val)
133 {
134 	struct elantech_data *etd = psmouse->private;
135 	int rc = 0;
136 
137 	if (reg < 0x07 || reg > 0x26)
138 		return -1;
139 
140 	if (reg > 0x11 && reg < 0x20)
141 		return -1;
142 
143 	switch (etd->hw_version) {
144 	case 1:
145 		if (psmouse_sliced_command(psmouse, ETP_REGISTER_WRITE) ||
146 		    psmouse_sliced_command(psmouse, reg) ||
147 		    psmouse_sliced_command(psmouse, val) ||
148 		    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
149 			rc = -1;
150 		}
151 		break;
152 
153 	case 2:
154 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
155 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
156 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
157 		    elantech_ps2_command(psmouse, NULL, reg) ||
158 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
159 		    elantech_ps2_command(psmouse, NULL, val) ||
160 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
161 			rc = -1;
162 		}
163 		break;
164 
165 	case 3:
166 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
167 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
168 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
169 		    elantech_ps2_command(psmouse, NULL, reg) ||
170 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
171 		    elantech_ps2_command(psmouse, NULL, val) ||
172 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
173 			rc = -1;
174 		}
175 		break;
176 
177 	case 4:
178 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
179 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
180 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
181 		    elantech_ps2_command(psmouse, NULL, reg) ||
182 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
183 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
184 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
185 		    elantech_ps2_command(psmouse, NULL, val) ||
186 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
187 			rc = -1;
188 		}
189 		break;
190 	}
191 
192 	if (rc)
193 		psmouse_err(psmouse,
194 			    "failed to write register 0x%02x with value 0x%02x.\n",
195 			    reg, val);
196 
197 	return rc;
198 }
199 
200 /*
201  * Dump a complete mouse movement packet to the syslog
202  */
203 static void elantech_packet_dump(struct psmouse *psmouse)
204 {
205 	int	i;
206 
207 	psmouse_printk(KERN_DEBUG, psmouse, "PS/2 packet [");
208 	for (i = 0; i < psmouse->pktsize; i++)
209 		printk("%s0x%02x ", i ? ", " : " ", psmouse->packet[i]);
210 	printk("]\n");
211 }
212 
213 /*
214  * Interpret complete data packets and report absolute mode input events for
215  * hardware version 1. (4 byte packets)
216  */
217 static void elantech_report_absolute_v1(struct psmouse *psmouse)
218 {
219 	struct input_dev *dev = psmouse->dev;
220 	struct elantech_data *etd = psmouse->private;
221 	unsigned char *packet = psmouse->packet;
222 	int fingers;
223 
224 	if (etd->fw_version < 0x020000) {
225 		/*
226 		 * byte 0:  D   U  p1  p2   1  p3   R   L
227 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
228 		 */
229 		fingers = ((packet[1] & 0x80) >> 7) +
230 				((packet[1] & 0x30) >> 4);
231 	} else {
232 		/*
233 		 * byte 0: n1  n0  p2  p1   1  p3   R   L
234 		 * byte 1:  0   0   0   0  x9  x8  y9  y8
235 		 */
236 		fingers = (packet[0] & 0xc0) >> 6;
237 	}
238 
239 	if (etd->jumpy_cursor) {
240 		if (fingers != 1) {
241 			etd->single_finger_reports = 0;
242 		} else if (etd->single_finger_reports < 2) {
243 			/* Discard first 2 reports of one finger, bogus */
244 			etd->single_finger_reports++;
245 			elantech_debug("discarding packet\n");
246 			return;
247 		}
248 	}
249 
250 	input_report_key(dev, BTN_TOUCH, fingers != 0);
251 
252 	/*
253 	 * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
254 	 * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
255 	 */
256 	if (fingers) {
257 		input_report_abs(dev, ABS_X,
258 			((packet[1] & 0x0c) << 6) | packet[2]);
259 		input_report_abs(dev, ABS_Y,
260 			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
261 	}
262 
263 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
264 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
265 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
266 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
267 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
268 
269 	if (etd->fw_version < 0x020000 &&
270 	    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
271 		/* rocker up */
272 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
273 		/* rocker down */
274 		input_report_key(dev, BTN_BACK, packet[0] & 0x80);
275 	}
276 
277 	input_sync(dev);
278 }
279 
280 static void elantech_set_slot(struct input_dev *dev, int slot, bool active,
281 			      unsigned int x, unsigned int y)
282 {
283 	input_mt_slot(dev, slot);
284 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
285 	if (active) {
286 		input_report_abs(dev, ABS_MT_POSITION_X, x);
287 		input_report_abs(dev, ABS_MT_POSITION_Y, y);
288 	}
289 }
290 
291 /* x1 < x2 and y1 < y2 when two fingers, x = y = 0 when not pressed */
292 static void elantech_report_semi_mt_data(struct input_dev *dev,
293 					 unsigned int num_fingers,
294 					 unsigned int x1, unsigned int y1,
295 					 unsigned int x2, unsigned int y2)
296 {
297 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
298 	elantech_set_slot(dev, 1, num_fingers == 2, x2, y2);
299 }
300 
301 /*
302  * Interpret complete data packets and report absolute mode input events for
303  * hardware version 2. (6 byte packets)
304  */
305 static void elantech_report_absolute_v2(struct psmouse *psmouse)
306 {
307 	struct elantech_data *etd = psmouse->private;
308 	struct input_dev *dev = psmouse->dev;
309 	unsigned char *packet = psmouse->packet;
310 	unsigned int fingers, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
311 	unsigned int width = 0, pres = 0;
312 
313 	/* byte 0: n1  n0   .   .   .   .   R   L */
314 	fingers = (packet[0] & 0xc0) >> 6;
315 
316 	switch (fingers) {
317 	case 3:
318 		/*
319 		 * Same as one finger, except report of more than 3 fingers:
320 		 * byte 3:  n4  .   w1  w0   .   .   .   .
321 		 */
322 		if (packet[3] & 0x80)
323 			fingers = 4;
324 		/* pass through... */
325 	case 1:
326 		/*
327 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
328 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
329 		 */
330 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
331 		/*
332 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
333 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
334 		 */
335 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
336 
337 		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
338 		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
339 		break;
340 
341 	case 2:
342 		/*
343 		 * The coordinate of each finger is reported separately
344 		 * with a lower resolution for two finger touches:
345 		 * byte 0:  .   .  ay8 ax8  .   .   .   .
346 		 * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
347 		 */
348 		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
349 		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
350 		y1 = etd->y_max -
351 			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
352 		/*
353 		 * byte 3:  .   .  by8 bx8  .   .   .   .
354 		 * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
355 		 */
356 		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
357 		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
358 		y2 = etd->y_max -
359 			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
360 
361 		/* Unknown so just report sensible values */
362 		pres = 127;
363 		width = 7;
364 		break;
365 	}
366 
367 	input_report_key(dev, BTN_TOUCH, fingers != 0);
368 	if (fingers != 0) {
369 		input_report_abs(dev, ABS_X, x1);
370 		input_report_abs(dev, ABS_Y, y1);
371 	}
372 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
373 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
374 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
375 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
376 	input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);
377 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
378 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
379 	if (etd->reports_pressure) {
380 		input_report_abs(dev, ABS_PRESSURE, pres);
381 		input_report_abs(dev, ABS_TOOL_WIDTH, width);
382 	}
383 
384 	input_sync(dev);
385 }
386 
387 /*
388  * Interpret complete data packets and report absolute mode input events for
389  * hardware version 3. (12 byte packets for two fingers)
390  */
391 static void elantech_report_absolute_v3(struct psmouse *psmouse,
392 					int packet_type)
393 {
394 	struct input_dev *dev = psmouse->dev;
395 	struct elantech_data *etd = psmouse->private;
396 	unsigned char *packet = psmouse->packet;
397 	unsigned int fingers = 0, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
398 	unsigned int width = 0, pres = 0;
399 
400 	/* byte 0: n1  n0   .   .   .   .   R   L */
401 	fingers = (packet[0] & 0xc0) >> 6;
402 
403 	switch (fingers) {
404 	case 3:
405 	case 1:
406 		/*
407 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
408 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
409 		 */
410 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
411 		/*
412 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
413 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
414 		 */
415 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
416 		break;
417 
418 	case 2:
419 		if (packet_type == PACKET_V3_HEAD) {
420 			/*
421 			 * byte 1:   .    .    .    .  ax11 ax10 ax9  ax8
422 			 * byte 2: ax7  ax6  ax5  ax4  ax3  ax2  ax1  ax0
423 			 */
424 			etd->mt[0].x = ((packet[1] & 0x0f) << 8) | packet[2];
425 			/*
426 			 * byte 4:   .    .    .    .  ay11 ay10 ay9  ay8
427 			 * byte 5: ay7  ay6  ay5  ay4  ay3  ay2  ay1  ay0
428 			 */
429 			etd->mt[0].y = etd->y_max -
430 				(((packet[4] & 0x0f) << 8) | packet[5]);
431 			/*
432 			 * wait for next packet
433 			 */
434 			return;
435 		}
436 
437 		/* packet_type == PACKET_V3_TAIL */
438 		x1 = etd->mt[0].x;
439 		y1 = etd->mt[0].y;
440 		x2 = ((packet[1] & 0x0f) << 8) | packet[2];
441 		y2 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
442 		break;
443 	}
444 
445 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
446 	width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
447 
448 	input_report_key(dev, BTN_TOUCH, fingers != 0);
449 	if (fingers != 0) {
450 		input_report_abs(dev, ABS_X, x1);
451 		input_report_abs(dev, ABS_Y, y1);
452 	}
453 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
454 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
455 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
456 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
457 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
458 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
459 	input_report_abs(dev, ABS_PRESSURE, pres);
460 	input_report_abs(dev, ABS_TOOL_WIDTH, width);
461 
462 	input_sync(dev);
463 }
464 
465 static void elantech_input_sync_v4(struct psmouse *psmouse)
466 {
467 	struct input_dev *dev = psmouse->dev;
468 	unsigned char *packet = psmouse->packet;
469 
470 	input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
471 	input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
472 	input_mt_report_pointer_emulation(dev, true);
473 	input_sync(dev);
474 }
475 
476 static void process_packet_status_v4(struct psmouse *psmouse)
477 {
478 	struct input_dev *dev = psmouse->dev;
479 	unsigned char *packet = psmouse->packet;
480 	unsigned fingers;
481 	int i;
482 
483 	/* notify finger state change */
484 	fingers = packet[1] & 0x1f;
485 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
486 		if ((fingers & (1 << i)) == 0) {
487 			input_mt_slot(dev, i);
488 			input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
489 		}
490 	}
491 
492 	elantech_input_sync_v4(psmouse);
493 }
494 
495 static void process_packet_head_v4(struct psmouse *psmouse)
496 {
497 	struct input_dev *dev = psmouse->dev;
498 	struct elantech_data *etd = psmouse->private;
499 	unsigned char *packet = psmouse->packet;
500 	int id = ((packet[3] & 0xe0) >> 5) - 1;
501 	int pres, traces;
502 
503 	if (id < 0)
504 		return;
505 
506 	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
507 	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
508 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
509 	traces = (packet[0] & 0xf0) >> 4;
510 
511 	input_mt_slot(dev, id);
512 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
513 
514 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
515 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
516 	input_report_abs(dev, ABS_MT_PRESSURE, pres);
517 	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, traces * etd->width);
518 	/* report this for backwards compatibility */
519 	input_report_abs(dev, ABS_TOOL_WIDTH, traces);
520 
521 	elantech_input_sync_v4(psmouse);
522 }
523 
524 static void process_packet_motion_v4(struct psmouse *psmouse)
525 {
526 	struct input_dev *dev = psmouse->dev;
527 	struct elantech_data *etd = psmouse->private;
528 	unsigned char *packet = psmouse->packet;
529 	int weight, delta_x1 = 0, delta_y1 = 0, delta_x2 = 0, delta_y2 = 0;
530 	int id, sid;
531 
532 	id = ((packet[0] & 0xe0) >> 5) - 1;
533 	if (id < 0)
534 		return;
535 
536 	sid = ((packet[3] & 0xe0) >> 5) - 1;
537 	weight = (packet[0] & 0x10) ? ETP_WEIGHT_VALUE : 1;
538 	/*
539 	 * Motion packets give us the delta of x, y values of specific fingers,
540 	 * but in two's complement. Let the compiler do the conversion for us.
541 	 * Also _enlarge_ the numbers to int, in case of overflow.
542 	 */
543 	delta_x1 = (signed char)packet[1];
544 	delta_y1 = (signed char)packet[2];
545 	delta_x2 = (signed char)packet[4];
546 	delta_y2 = (signed char)packet[5];
547 
548 	etd->mt[id].x += delta_x1 * weight;
549 	etd->mt[id].y -= delta_y1 * weight;
550 	input_mt_slot(dev, id);
551 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
552 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
553 
554 	if (sid >= 0) {
555 		etd->mt[sid].x += delta_x2 * weight;
556 		etd->mt[sid].y -= delta_y2 * weight;
557 		input_mt_slot(dev, sid);
558 		input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[sid].x);
559 		input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[sid].y);
560 	}
561 
562 	elantech_input_sync_v4(psmouse);
563 }
564 
565 static void elantech_report_absolute_v4(struct psmouse *psmouse,
566 					int packet_type)
567 {
568 	switch (packet_type) {
569 	case PACKET_V4_STATUS:
570 		process_packet_status_v4(psmouse);
571 		break;
572 
573 	case PACKET_V4_HEAD:
574 		process_packet_head_v4(psmouse);
575 		break;
576 
577 	case PACKET_V4_MOTION:
578 		process_packet_motion_v4(psmouse);
579 		break;
580 
581 	case PACKET_UNKNOWN:
582 	default:
583 		/* impossible to get here */
584 		break;
585 	}
586 }
587 
588 static int elantech_packet_check_v1(struct psmouse *psmouse)
589 {
590 	struct elantech_data *etd = psmouse->private;
591 	unsigned char *packet = psmouse->packet;
592 	unsigned char p1, p2, p3;
593 
594 	/* Parity bits are placed differently */
595 	if (etd->fw_version < 0x020000) {
596 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
597 		p1 = (packet[0] & 0x20) >> 5;
598 		p2 = (packet[0] & 0x10) >> 4;
599 	} else {
600 		/* byte 0: n1  n0  p2  p1   1  p3   R   L */
601 		p1 = (packet[0] & 0x10) >> 4;
602 		p2 = (packet[0] & 0x20) >> 5;
603 	}
604 
605 	p3 = (packet[0] & 0x04) >> 2;
606 
607 	return etd->parity[packet[1]] == p1 &&
608 	       etd->parity[packet[2]] == p2 &&
609 	       etd->parity[packet[3]] == p3;
610 }
611 
612 static int elantech_debounce_check_v2(struct psmouse *psmouse)
613 {
614         /*
615          * When we encounter packet that matches this exactly, it means the
616          * hardware is in debounce status. Just ignore the whole packet.
617          */
618         const u8 debounce_packet[] = { 0x84, 0xff, 0xff, 0x02, 0xff, 0xff };
619         unsigned char *packet = psmouse->packet;
620 
621         return !memcmp(packet, debounce_packet, sizeof(debounce_packet));
622 }
623 
624 static int elantech_packet_check_v2(struct psmouse *psmouse)
625 {
626 	struct elantech_data *etd = psmouse->private;
627 	unsigned char *packet = psmouse->packet;
628 
629 	/*
630 	 * V2 hardware has two flavors. Older ones that do not report pressure,
631 	 * and newer ones that reports pressure and width. With newer ones, all
632 	 * packets (1, 2, 3 finger touch) have the same constant bits. With
633 	 * older ones, 1/3 finger touch packets and 2 finger touch packets
634 	 * have different constant bits.
635 	 * With all three cases, if the constant bits are not exactly what I
636 	 * expected, I consider them invalid.
637 	 */
638 	if (etd->reports_pressure)
639 		return (packet[0] & 0x0c) == 0x04 &&
640 		       (packet[3] & 0x0f) == 0x02;
641 
642 	if ((packet[0] & 0xc0) == 0x80)
643 		return (packet[0] & 0x0c) == 0x0c &&
644 		       (packet[3] & 0x0e) == 0x08;
645 
646 	return (packet[0] & 0x3c) == 0x3c &&
647 	       (packet[1] & 0xf0) == 0x00 &&
648 	       (packet[3] & 0x3e) == 0x38 &&
649 	       (packet[4] & 0xf0) == 0x00;
650 }
651 
652 /*
653  * We check the constant bits to determine what packet type we get,
654  * so packet checking is mandatory for v3 and later hardware.
655  */
656 static int elantech_packet_check_v3(struct psmouse *psmouse)
657 {
658 	const u8 debounce_packet[] = { 0xc4, 0xff, 0xff, 0x02, 0xff, 0xff };
659 	unsigned char *packet = psmouse->packet;
660 
661 	/*
662 	 * check debounce first, it has the same signature in byte 0
663 	 * and byte 3 as PACKET_V3_HEAD.
664 	 */
665 	if (!memcmp(packet, debounce_packet, sizeof(debounce_packet)))
666 		return PACKET_DEBOUNCE;
667 
668 	if ((packet[0] & 0x0c) == 0x04 && (packet[3] & 0xcf) == 0x02)
669 		return PACKET_V3_HEAD;
670 
671 	if ((packet[0] & 0x0c) == 0x0c && (packet[3] & 0xce) == 0x0c)
672 		return PACKET_V3_TAIL;
673 
674 	return PACKET_UNKNOWN;
675 }
676 
677 static int elantech_packet_check_v4(struct psmouse *psmouse)
678 {
679 	unsigned char *packet = psmouse->packet;
680 
681 	if ((packet[0] & 0x0c) == 0x04 &&
682 	    (packet[3] & 0x1f) == 0x11)
683 		return PACKET_V4_HEAD;
684 
685 	if ((packet[0] & 0x0c) == 0x04 &&
686 	    (packet[3] & 0x1f) == 0x12)
687 		return PACKET_V4_MOTION;
688 
689 	if ((packet[0] & 0x0c) == 0x04 &&
690 	    (packet[3] & 0x1f) == 0x10)
691 		return PACKET_V4_STATUS;
692 
693 	return PACKET_UNKNOWN;
694 }
695 
696 /*
697  * Process byte stream from mouse and handle complete packets
698  */
699 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
700 {
701 	struct elantech_data *etd = psmouse->private;
702 	int packet_type;
703 
704 	if (psmouse->pktcnt < psmouse->pktsize)
705 		return PSMOUSE_GOOD_DATA;
706 
707 	if (etd->debug > 1)
708 		elantech_packet_dump(psmouse);
709 
710 	switch (etd->hw_version) {
711 	case 1:
712 		if (etd->paritycheck && !elantech_packet_check_v1(psmouse))
713 			return PSMOUSE_BAD_DATA;
714 
715 		elantech_report_absolute_v1(psmouse);
716 		break;
717 
718 	case 2:
719 		/* ignore debounce */
720 		if (elantech_debounce_check_v2(psmouse))
721 			return PSMOUSE_FULL_PACKET;
722 
723 		if (etd->paritycheck && !elantech_packet_check_v2(psmouse))
724 			return PSMOUSE_BAD_DATA;
725 
726 		elantech_report_absolute_v2(psmouse);
727 		break;
728 
729 	case 3:
730 		packet_type = elantech_packet_check_v3(psmouse);
731 		/* ignore debounce */
732 		if (packet_type == PACKET_DEBOUNCE)
733 			return PSMOUSE_FULL_PACKET;
734 
735 		if (packet_type == PACKET_UNKNOWN)
736 			return PSMOUSE_BAD_DATA;
737 
738 		elantech_report_absolute_v3(psmouse, packet_type);
739 		break;
740 
741 	case 4:
742 		packet_type = elantech_packet_check_v4(psmouse);
743 		if (packet_type == PACKET_UNKNOWN)
744 			return PSMOUSE_BAD_DATA;
745 
746 		elantech_report_absolute_v4(psmouse, packet_type);
747 		break;
748 	}
749 
750 	return PSMOUSE_FULL_PACKET;
751 }
752 
753 /*
754  * Put the touchpad into absolute mode
755  */
756 static int elantech_set_absolute_mode(struct psmouse *psmouse)
757 {
758 	struct elantech_data *etd = psmouse->private;
759 	unsigned char val;
760 	int tries = ETP_READ_BACK_TRIES;
761 	int rc = 0;
762 
763 	switch (etd->hw_version) {
764 	case 1:
765 		etd->reg_10 = 0x16;
766 		etd->reg_11 = 0x8f;
767 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
768 		    elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
769 			rc = -1;
770 		}
771 		break;
772 
773 	case 2:
774 					/* Windows driver values */
775 		etd->reg_10 = 0x54;
776 		etd->reg_11 = 0x88;	/* 0x8a */
777 		etd->reg_21 = 0x60;	/* 0x00 */
778 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
779 		    elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
780 		    elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
781 			rc = -1;
782 		}
783 		break;
784 
785 	case 3:
786 		etd->reg_10 = 0x0b;
787 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10))
788 			rc = -1;
789 
790 		break;
791 
792 	case 4:
793 		etd->reg_07 = 0x01;
794 		if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
795 			rc = -1;
796 
797 		goto skip_readback_reg_10; /* v4 has no reg 0x10 to read */
798 	}
799 
800 	if (rc == 0) {
801 		/*
802 		 * Read back reg 0x10. For hardware version 1 we must make
803 		 * sure the absolute mode bit is set. For hardware version 2
804 		 * the touchpad is probably initializing and not ready until
805 		 * we read back the value we just wrote.
806 		 */
807 		do {
808 			rc = elantech_read_reg(psmouse, 0x10, &val);
809 			if (rc == 0)
810 				break;
811 			tries--;
812 			elantech_debug("retrying read (%d).\n", tries);
813 			msleep(ETP_READ_BACK_DELAY);
814 		} while (tries > 0);
815 
816 		if (rc) {
817 			psmouse_err(psmouse,
818 				    "failed to read back register 0x10.\n");
819 		} else if (etd->hw_version == 1 &&
820 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
821 			psmouse_err(psmouse,
822 				    "touchpad refuses to switch to absolute mode.\n");
823 			rc = -1;
824 		}
825 	}
826 
827  skip_readback_reg_10:
828 	if (rc)
829 		psmouse_err(psmouse, "failed to initialise registers.\n");
830 
831 	return rc;
832 }
833 
834 static int elantech_set_range(struct psmouse *psmouse,
835 			      unsigned int *x_min, unsigned int *y_min,
836 			      unsigned int *x_max, unsigned int *y_max,
837 			      unsigned int *width)
838 {
839 	struct elantech_data *etd = psmouse->private;
840 	unsigned char param[3];
841 	unsigned char traces;
842 
843 	switch (etd->hw_version) {
844 	case 1:
845 		*x_min = ETP_XMIN_V1;
846 		*y_min = ETP_YMIN_V1;
847 		*x_max = ETP_XMAX_V1;
848 		*y_max = ETP_YMAX_V1;
849 		break;
850 
851 	case 2:
852 		if (etd->fw_version == 0x020800 ||
853 		    etd->fw_version == 0x020b00 ||
854 		    etd->fw_version == 0x020030) {
855 			*x_min = ETP_XMIN_V2;
856 			*y_min = ETP_YMIN_V2;
857 			*x_max = ETP_XMAX_V2;
858 			*y_max = ETP_YMAX_V2;
859 		} else {
860 			int i;
861 			int fixed_dpi;
862 
863 			i = (etd->fw_version > 0x020800 &&
864 			     etd->fw_version < 0x020900) ? 1 : 2;
865 
866 			if (synaptics_send_cmd(psmouse, ETP_FW_ID_QUERY, param))
867 				return -1;
868 
869 			fixed_dpi = param[1] & 0x10;
870 
871 			if (((etd->fw_version >> 16) == 0x14) && fixed_dpi) {
872 				if (synaptics_send_cmd(psmouse, ETP_SAMPLE_QUERY, param))
873 					return -1;
874 
875 				*x_max = (etd->capabilities[1] - i) * param[1] / 2;
876 				*y_max = (etd->capabilities[2] - i) * param[2] / 2;
877 			} else if (etd->fw_version == 0x040216) {
878 				*x_max = 819;
879 				*y_max = 405;
880 			} else if (etd->fw_version == 0x040219 || etd->fw_version == 0x040215) {
881 				*x_max = 900;
882 				*y_max = 500;
883 			} else {
884 				*x_max = (etd->capabilities[1] - i) * 64;
885 				*y_max = (etd->capabilities[2] - i) * 64;
886 			}
887 		}
888 		break;
889 
890 	case 3:
891 		if (synaptics_send_cmd(psmouse, ETP_FW_ID_QUERY, param))
892 			return -1;
893 
894 		*x_max = (0x0f & param[0]) << 8 | param[1];
895 		*y_max = (0xf0 & param[0]) << 4 | param[2];
896 		break;
897 
898 	case 4:
899 		if (synaptics_send_cmd(psmouse, ETP_FW_ID_QUERY, param))
900 			return -1;
901 
902 		*x_max = (0x0f & param[0]) << 8 | param[1];
903 		*y_max = (0xf0 & param[0]) << 4 | param[2];
904 		traces = etd->capabilities[1];
905 		if ((traces < 2) || (traces > *x_max))
906 			return -1;
907 
908 		*width = *x_max / (traces - 1);
909 		break;
910 	}
911 
912 	return 0;
913 }
914 
915 /*
916  * Set the appropriate event bits for the input subsystem
917  */
918 static int elantech_set_input_params(struct psmouse *psmouse)
919 {
920 	struct input_dev *dev = psmouse->dev;
921 	struct elantech_data *etd = psmouse->private;
922 	unsigned int x_min = 0, y_min = 0, x_max = 0, y_max = 0, width = 0;
923 
924 	if (elantech_set_range(psmouse, &x_min, &y_min, &x_max, &y_max, &width))
925 		return -1;
926 
927 	__set_bit(EV_KEY, dev->evbit);
928 	__set_bit(EV_ABS, dev->evbit);
929 	__clear_bit(EV_REL, dev->evbit);
930 
931 	__set_bit(BTN_LEFT, dev->keybit);
932 	__set_bit(BTN_RIGHT, dev->keybit);
933 
934 	__set_bit(BTN_TOUCH, dev->keybit);
935 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
936 	__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
937 	__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
938 
939 	switch (etd->hw_version) {
940 	case 1:
941 		/* Rocker button */
942 		if (etd->fw_version < 0x020000 &&
943 		    (etd->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
944 			__set_bit(BTN_FORWARD, dev->keybit);
945 			__set_bit(BTN_BACK, dev->keybit);
946 		}
947 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
948 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
949 		break;
950 
951 	case 2:
952 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
953 		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
954 		/* fall through */
955 	case 3:
956 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
957 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
958 		if (etd->reports_pressure) {
959 			input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
960 					     ETP_PMAX_V2, 0, 0);
961 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
962 					     ETP_WMAX_V2, 0, 0);
963 		}
964 		input_mt_init_slots(dev, 2);
965 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
966 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
967 		break;
968 
969 	case 4:
970 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
971 		/* For X to recognize me as touchpad. */
972 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
973 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
974 		/*
975 		 * range of pressure and width is the same as v2,
976 		 * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
977 		 */
978 		input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
979 				     ETP_PMAX_V2, 0, 0);
980 		input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
981 				     ETP_WMAX_V2, 0, 0);
982 		/* Multitouch capable pad, up to 5 fingers. */
983 		input_mt_init_slots(dev, ETP_MAX_FINGERS);
984 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
985 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
986 		input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
987 				     ETP_PMAX_V2, 0, 0);
988 		/*
989 		 * The firmware reports how many trace lines the finger spans,
990 		 * convert to surface unit as Protocol-B requires.
991 		 */
992 		input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 0,
993 				     ETP_WMAX_V2 * width, 0, 0);
994 		break;
995 	}
996 
997 	etd->y_max = y_max;
998 	etd->width = width;
999 
1000 	return 0;
1001 }
1002 
1003 struct elantech_attr_data {
1004 	size_t		field_offset;
1005 	unsigned char	reg;
1006 };
1007 
1008 /*
1009  * Display a register value by reading a sysfs entry
1010  */
1011 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
1012 					char *buf)
1013 {
1014 	struct elantech_data *etd = psmouse->private;
1015 	struct elantech_attr_data *attr = data;
1016 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1017 	int rc = 0;
1018 
1019 	if (attr->reg)
1020 		rc = elantech_read_reg(psmouse, attr->reg, reg);
1021 
1022 	return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
1023 }
1024 
1025 /*
1026  * Write a register value by writing a sysfs entry
1027  */
1028 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
1029 				     void *data, const char *buf, size_t count)
1030 {
1031 	struct elantech_data *etd = psmouse->private;
1032 	struct elantech_attr_data *attr = data;
1033 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1034 	unsigned long value;
1035 	int err;
1036 
1037 	err = strict_strtoul(buf, 16, &value);
1038 	if (err)
1039 		return err;
1040 
1041 	if (value > 0xff)
1042 		return -EINVAL;
1043 
1044 	/* Do we need to preserve some bits for version 2 hardware too? */
1045 	if (etd->hw_version == 1) {
1046 		if (attr->reg == 0x10)
1047 			/* Force absolute mode always on */
1048 			value |= ETP_R10_ABSOLUTE_MODE;
1049 		else if (attr->reg == 0x11)
1050 			/* Force 4 byte mode always on */
1051 			value |= ETP_R11_4_BYTE_MODE;
1052 	}
1053 
1054 	if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
1055 		*reg = value;
1056 
1057 	return count;
1058 }
1059 
1060 #define ELANTECH_INT_ATTR(_name, _register)				\
1061 	static struct elantech_attr_data elantech_attr_##_name = {	\
1062 		.field_offset = offsetof(struct elantech_data, _name),	\
1063 		.reg = _register,					\
1064 	};								\
1065 	PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,			\
1066 			    &elantech_attr_##_name,			\
1067 			    elantech_show_int_attr,			\
1068 			    elantech_set_int_attr)
1069 
1070 ELANTECH_INT_ATTR(reg_07, 0x07);
1071 ELANTECH_INT_ATTR(reg_10, 0x10);
1072 ELANTECH_INT_ATTR(reg_11, 0x11);
1073 ELANTECH_INT_ATTR(reg_20, 0x20);
1074 ELANTECH_INT_ATTR(reg_21, 0x21);
1075 ELANTECH_INT_ATTR(reg_22, 0x22);
1076 ELANTECH_INT_ATTR(reg_23, 0x23);
1077 ELANTECH_INT_ATTR(reg_24, 0x24);
1078 ELANTECH_INT_ATTR(reg_25, 0x25);
1079 ELANTECH_INT_ATTR(reg_26, 0x26);
1080 ELANTECH_INT_ATTR(debug, 0);
1081 ELANTECH_INT_ATTR(paritycheck, 0);
1082 
1083 static struct attribute *elantech_attrs[] = {
1084 	&psmouse_attr_reg_07.dattr.attr,
1085 	&psmouse_attr_reg_10.dattr.attr,
1086 	&psmouse_attr_reg_11.dattr.attr,
1087 	&psmouse_attr_reg_20.dattr.attr,
1088 	&psmouse_attr_reg_21.dattr.attr,
1089 	&psmouse_attr_reg_22.dattr.attr,
1090 	&psmouse_attr_reg_23.dattr.attr,
1091 	&psmouse_attr_reg_24.dattr.attr,
1092 	&psmouse_attr_reg_25.dattr.attr,
1093 	&psmouse_attr_reg_26.dattr.attr,
1094 	&psmouse_attr_debug.dattr.attr,
1095 	&psmouse_attr_paritycheck.dattr.attr,
1096 	NULL
1097 };
1098 
1099 static struct attribute_group elantech_attr_group = {
1100 	.attrs = elantech_attrs,
1101 };
1102 
1103 static bool elantech_is_signature_valid(const unsigned char *param)
1104 {
1105 	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
1106 	int i;
1107 
1108 	if (param[0] == 0)
1109 		return false;
1110 
1111 	if (param[1] == 0)
1112 		return true;
1113 
1114 	for (i = 0; i < ARRAY_SIZE(rates); i++)
1115 		if (param[2] == rates[i])
1116 			return false;
1117 
1118 	return true;
1119 }
1120 
1121 /*
1122  * Use magic knock to detect Elantech touchpad
1123  */
1124 int elantech_detect(struct psmouse *psmouse, bool set_properties)
1125 {
1126 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1127 	unsigned char param[3];
1128 
1129 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1130 
1131 	if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
1132 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1133 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1134 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1135 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1136 		psmouse_dbg(psmouse, "sending Elantech magic knock failed.\n");
1137 		return -1;
1138 	}
1139 
1140 	/*
1141 	 * Report this in case there are Elantech models that use a different
1142 	 * set of magic numbers
1143 	 */
1144 	if (param[0] != 0x3c || param[1] != 0x03 ||
1145 	    (param[2] != 0xc8 && param[2] != 0x00)) {
1146 		psmouse_dbg(psmouse,
1147 			    "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
1148 			    param[0], param[1], param[2]);
1149 		return -1;
1150 	}
1151 
1152 	/*
1153 	 * Query touchpad's firmware version and see if it reports known
1154 	 * value to avoid mis-detection. Logitech mice are known to respond
1155 	 * to Elantech magic knock and there might be more.
1156 	 */
1157 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1158 		psmouse_dbg(psmouse, "failed to query firmware version.\n");
1159 		return -1;
1160 	}
1161 
1162 	psmouse_dbg(psmouse,
1163 		    "Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
1164 		    param[0], param[1], param[2]);
1165 
1166 	if (!elantech_is_signature_valid(param)) {
1167 		psmouse_dbg(psmouse,
1168 			    "Probably not a real Elantech touchpad. Aborting.\n");
1169 		return -1;
1170 	}
1171 
1172 	if (set_properties) {
1173 		psmouse->vendor = "Elantech";
1174 		psmouse->name = "Touchpad";
1175 	}
1176 
1177 	return 0;
1178 }
1179 
1180 /*
1181  * Clean up sysfs entries when disconnecting
1182  */
1183 static void elantech_disconnect(struct psmouse *psmouse)
1184 {
1185 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1186 			   &elantech_attr_group);
1187 	kfree(psmouse->private);
1188 	psmouse->private = NULL;
1189 }
1190 
1191 /*
1192  * Put the touchpad back into absolute mode when reconnecting
1193  */
1194 static int elantech_reconnect(struct psmouse *psmouse)
1195 {
1196 	if (elantech_detect(psmouse, 0))
1197 		return -1;
1198 
1199 	if (elantech_set_absolute_mode(psmouse)) {
1200 		psmouse_err(psmouse,
1201 			    "failed to put touchpad back into absolute mode.\n");
1202 		return -1;
1203 	}
1204 
1205 	return 0;
1206 }
1207 
1208 /*
1209  * determine hardware version and set some properties according to it.
1210  */
1211 static int elantech_set_properties(struct elantech_data *etd)
1212 {
1213 	int ver = (etd->fw_version & 0x0f0000) >> 16;
1214 
1215 	if (etd->fw_version < 0x020030 || etd->fw_version == 0x020600)
1216 		etd->hw_version = 1;
1217 	else if (etd->fw_version < 0x150600)
1218 		etd->hw_version = 2;
1219 	else if (ver == 5)
1220 		etd->hw_version = 3;
1221 	else if (ver == 6)
1222 		etd->hw_version = 4;
1223 	else
1224 		return -1;
1225 
1226 	/*
1227 	 * Turn on packet checking by default.
1228 	 */
1229 	etd->paritycheck = 1;
1230 
1231 	/*
1232 	 * This firmware suffers from misreporting coordinates when
1233 	 * a touch action starts causing the mouse cursor or scrolled page
1234 	 * to jump. Enable a workaround.
1235 	 */
1236 	etd->jumpy_cursor =
1237 		(etd->fw_version == 0x020022 || etd->fw_version == 0x020600);
1238 
1239 	if (etd->hw_version > 1) {
1240 		/* For now show extra debug information */
1241 		etd->debug = 1;
1242 
1243 		if (etd->fw_version >= 0x020800)
1244 			etd->reports_pressure = true;
1245 	}
1246 
1247 	return 0;
1248 }
1249 
1250 /*
1251  * Initialize the touchpad and create sysfs entries
1252  */
1253 int elantech_init(struct psmouse *psmouse)
1254 {
1255 	struct elantech_data *etd;
1256 	int i, error;
1257 	unsigned char param[3];
1258 
1259 	psmouse->private = etd = kzalloc(sizeof(struct elantech_data), GFP_KERNEL);
1260 	if (!etd)
1261 		return -ENOMEM;
1262 
1263 	etd->parity[0] = 1;
1264 	for (i = 1; i < 256; i++)
1265 		etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
1266 
1267 	/*
1268 	 * Do the version query again so we can store the result
1269 	 */
1270 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1271 		psmouse_err(psmouse, "failed to query firmware version.\n");
1272 		goto init_fail;
1273 	}
1274 	etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
1275 
1276 	if (elantech_set_properties(etd)) {
1277 		psmouse_err(psmouse, "unknown hardware version, aborting...\n");
1278 		goto init_fail;
1279 	}
1280 	psmouse_info(psmouse,
1281 		     "assuming hardware version %d (with firmware version 0x%02x%02x%02x)\n",
1282 		     etd->hw_version, param[0], param[1], param[2]);
1283 
1284 	if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY,
1285 	    etd->capabilities)) {
1286 		psmouse_err(psmouse, "failed to query capabilities.\n");
1287 		goto init_fail;
1288 	}
1289 	psmouse_info(psmouse,
1290 		     "Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
1291 		     etd->capabilities[0], etd->capabilities[1],
1292 		     etd->capabilities[2]);
1293 
1294 	if (elantech_set_absolute_mode(psmouse)) {
1295 		psmouse_err(psmouse,
1296 			    "failed to put touchpad into absolute mode.\n");
1297 		goto init_fail;
1298 	}
1299 
1300 	if (elantech_set_input_params(psmouse)) {
1301 		psmouse_err(psmouse, "failed to query touchpad range.\n");
1302 		goto init_fail;
1303 	}
1304 
1305 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
1306 				   &elantech_attr_group);
1307 	if (error) {
1308 		psmouse_err(psmouse,
1309 			    "failed to create sysfs attributes, error: %d.\n",
1310 			    error);
1311 		goto init_fail;
1312 	}
1313 
1314 	psmouse->protocol_handler = elantech_process_byte;
1315 	psmouse->disconnect = elantech_disconnect;
1316 	psmouse->reconnect = elantech_reconnect;
1317 	psmouse->pktsize = etd->hw_version > 1 ? 6 : 4;
1318 
1319 	return 0;
1320 
1321  init_fail:
1322 	kfree(etd);
1323 	return -1;
1324 }
1325