xref: /linux/drivers/input/mouse/elantech.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Elantech Touchpad driver (v6)
4  *
5  * Copyright (C) 2007-2009 Arjan Opmeer <arjan@opmeer.net>
6  *
7  * Trademarks are the property of their respective owners.
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/dmi.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/i2c.h>
15 #include <linux/input.h>
16 #include <linux/input/mt.h>
17 #include <linux/platform_device.h>
18 #include <linux/serio.h>
19 #include <linux/libps2.h>
20 #include <linux/unaligned.h>
21 #include "psmouse.h"
22 #include "elantech.h"
23 #include "elan_i2c.h"
24 
25 #define elantech_debug(fmt, ...)					\
26 	do {								\
27 		if (etd->info.debug)					\
28 			psmouse_printk(KERN_DEBUG, psmouse,		\
29 					fmt, ##__VA_ARGS__);		\
30 	} while (0)
31 
32 /*
33  * Send a Synaptics style sliced query command
34  */
35 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
36 				unsigned char *param)
37 {
38 	if (ps2_sliced_command(&psmouse->ps2dev, c) ||
39 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
40 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
41 		return -1;
42 	}
43 
44 	return 0;
45 }
46 
47 /*
48  * V3 and later support this fast command
49  */
50 static int elantech_send_cmd(struct psmouse *psmouse, unsigned char c,
51 				unsigned char *param)
52 {
53 	struct ps2dev *ps2dev = &psmouse->ps2dev;
54 
55 	if (ps2_command(ps2dev, NULL, ETP_PS2_CUSTOM_COMMAND) ||
56 	    ps2_command(ps2dev, NULL, c) ||
57 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
58 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
59 		return -1;
60 	}
61 
62 	return 0;
63 }
64 
65 /*
66  * A retrying version of ps2_command
67  */
68 static int elantech_ps2_command(struct psmouse *psmouse,
69 				unsigned char *param, int command)
70 {
71 	struct ps2dev *ps2dev = &psmouse->ps2dev;
72 	struct elantech_data *etd = psmouse->private;
73 	int rc;
74 	int tries = ETP_PS2_COMMAND_TRIES;
75 
76 	do {
77 		rc = ps2_command(ps2dev, param, command);
78 		if (rc == 0)
79 			break;
80 		tries--;
81 		elantech_debug("retrying ps2 command 0x%02x (%d).\n",
82 				command, tries);
83 		msleep(ETP_PS2_COMMAND_DELAY);
84 	} while (tries > 0);
85 
86 	if (rc)
87 		psmouse_err(psmouse, "ps2 command 0x%02x failed.\n", command);
88 
89 	return rc;
90 }
91 
92 /*
93  * Send an Elantech style special command to read 3 bytes from a register
94  */
95 static int elantech_read_reg_params(struct psmouse *psmouse, u8 reg, u8 *param)
96 {
97 	if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
98 	    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
99 	    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
100 	    elantech_ps2_command(psmouse, NULL, reg) ||
101 	    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
102 		psmouse_err(psmouse,
103 			    "failed to read register %#02x\n", reg);
104 		return -EIO;
105 	}
106 
107 	return 0;
108 }
109 
110 /*
111  * Send an Elantech style special command to write a register with a parameter
112  */
113 static int elantech_write_reg_params(struct psmouse *psmouse, u8 reg, u8 *param)
114 {
115 	if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
116 	    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
117 	    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
118 	    elantech_ps2_command(psmouse, NULL, reg) ||
119 	    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
120 	    elantech_ps2_command(psmouse, NULL, param[0]) ||
121 	    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
122 	    elantech_ps2_command(psmouse, NULL, param[1]) ||
123 	    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
124 		psmouse_err(psmouse,
125 			    "failed to write register %#02x with value %#02x%#02x\n",
126 			    reg, param[0], param[1]);
127 		return -EIO;
128 	}
129 
130 	return 0;
131 }
132 
133 /*
134  * Send an Elantech style special command to read a value from a register
135  */
136 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
137 				unsigned char *val)
138 {
139 	struct elantech_data *etd = psmouse->private;
140 	unsigned char param[3];
141 	int rc = 0;
142 
143 	if (reg < 0x07 || reg > 0x26)
144 		return -1;
145 
146 	if (reg > 0x11 && reg < 0x20)
147 		return -1;
148 
149 	switch (etd->info.hw_version) {
150 	case 1:
151 		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_READ) ||
152 		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
153 		    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
154 			rc = -1;
155 		}
156 		break;
157 
158 	case 2:
159 		if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
160 		    elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
161 		    elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
162 		    elantech_ps2_command(psmouse,  NULL, reg) ||
163 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
164 			rc = -1;
165 		}
166 		break;
167 
168 	case 3 ... 4:
169 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
170 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
171 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
172 		    elantech_ps2_command(psmouse, NULL, reg) ||
173 		    elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
174 			rc = -1;
175 		}
176 		break;
177 	}
178 
179 	if (rc)
180 		psmouse_err(psmouse, "failed to read register 0x%02x.\n", reg);
181 	else if (etd->info.hw_version != 4)
182 		*val = param[0];
183 	else
184 		*val = param[1];
185 
186 	return rc;
187 }
188 
189 /*
190  * Send an Elantech style special command to write a register with a value
191  */
192 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
193 				unsigned char val)
194 {
195 	struct elantech_data *etd = psmouse->private;
196 	int rc = 0;
197 
198 	if (reg < 0x07 || reg > 0x26)
199 		return -1;
200 
201 	if (reg > 0x11 && reg < 0x20)
202 		return -1;
203 
204 	switch (etd->info.hw_version) {
205 	case 1:
206 		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_WRITE) ||
207 		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
208 		    ps2_sliced_command(&psmouse->ps2dev, val) ||
209 		    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
210 			rc = -1;
211 		}
212 		break;
213 
214 	case 2:
215 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
216 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
217 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
218 		    elantech_ps2_command(psmouse, NULL, reg) ||
219 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
220 		    elantech_ps2_command(psmouse, NULL, val) ||
221 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
222 			rc = -1;
223 		}
224 		break;
225 
226 	case 3:
227 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
228 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
229 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
230 		    elantech_ps2_command(psmouse, NULL, reg) ||
231 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
232 		    elantech_ps2_command(psmouse, NULL, val) ||
233 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
234 			rc = -1;
235 		}
236 		break;
237 
238 	case 4:
239 		if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
240 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
241 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
242 		    elantech_ps2_command(psmouse, NULL, reg) ||
243 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
244 		    elantech_ps2_command(psmouse, NULL, ETP_REGISTER_READWRITE) ||
245 		    elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
246 		    elantech_ps2_command(psmouse, NULL, val) ||
247 		    elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
248 			rc = -1;
249 		}
250 		break;
251 	}
252 
253 	if (rc)
254 		psmouse_err(psmouse,
255 			    "failed to write register 0x%02x with value 0x%02x.\n",
256 			    reg, val);
257 
258 	return rc;
259 }
260 
261 /*
262  * Dump a complete mouse movement packet to the syslog
263  */
264 static void elantech_packet_dump(struct psmouse *psmouse)
265 {
266 	psmouse_printk(KERN_DEBUG, psmouse, "PS/2 packet [%*ph]\n",
267 		       psmouse->pktsize, psmouse->packet);
268 }
269 
270 /*
271  * Advertise INPUT_PROP_BUTTONPAD for clickpads. The testing of bit 12 in
272  * fw_version for this is based on the following fw_version & caps table:
273  *
274  * Laptop-model:           fw_version:     caps:           buttons:
275  * Acer S3                 0x461f00        10, 13, 0e      clickpad
276  * Acer S7-392             0x581f01        50, 17, 0d      clickpad
277  * Acer V5-131             0x461f02        01, 16, 0c      clickpad
278  * Acer V5-551             0x461f00        ?               clickpad
279  * Asus K53SV              0x450f01        78, 15, 0c      2 hw buttons
280  * Asus G46VW              0x460f02        00, 18, 0c      2 hw buttons
281  * Asus G750JX             0x360f00        00, 16, 0c      2 hw buttons
282  * Asus TP500LN            0x381f17        10, 14, 0e      clickpad
283  * Asus X750JN             0x381f17        10, 14, 0e      clickpad
284  * Asus UX31               0x361f00        20, 15, 0e      clickpad
285  * Asus UX32VD             0x361f02        00, 15, 0e      clickpad
286  * Avatar AVIU-145A2       0x361f00        ?               clickpad
287  * Fujitsu CELSIUS H760    0x570f02        40, 14, 0c      3 hw buttons (**)
288  * Fujitsu CELSIUS H780    0x5d0f02        41, 16, 0d      3 hw buttons (**)
289  * Fujitsu LIFEBOOK E544   0x470f00        d0, 12, 09      2 hw buttons
290  * Fujitsu LIFEBOOK E546   0x470f00        50, 12, 09      2 hw buttons
291  * Fujitsu LIFEBOOK E547   0x470f00        50, 12, 09      2 hw buttons
292  * Fujitsu LIFEBOOK E554   0x570f01        40, 14, 0c      2 hw buttons
293  * Fujitsu LIFEBOOK E557   0x570f01        40, 14, 0c      2 hw buttons
294  * Fujitsu T725            0x470f01        05, 12, 09      2 hw buttons
295  * Fujitsu H730            0x570f00        c0, 14, 0c      3 hw buttons (**)
296  * Gigabyte U2442          0x450f01        58, 17, 0c      2 hw buttons
297  * Lenovo L430             0x350f02        b9, 15, 0c      2 hw buttons (*)
298  * Lenovo L530             0x350f02        b9, 15, 0c      2 hw buttons (*)
299  * Samsung NF210           0x150b00        78, 14, 0a      2 hw buttons
300  * Samsung NP770Z5E        0x575f01        10, 15, 0f      clickpad
301  * Samsung NP700Z5B        0x361f06        21, 15, 0f      clickpad
302  * Samsung NP900X3E-A02    0x575f03        ?               clickpad
303  * Samsung NP-QX410        0x851b00        19, 14, 0c      clickpad
304  * Samsung RC512           0x450f00        08, 15, 0c      2 hw buttons
305  * Samsung RF710           0x450f00        ?               2 hw buttons
306  * System76 Pangolin       0x250f01        ?               2 hw buttons
307  * (*) + 3 trackpoint buttons
308  * (**) + 0 trackpoint buttons
309  * Note: Lenovo L430 and Lenovo L530 have the same fw_version/caps
310  */
311 static inline int elantech_is_buttonpad(struct elantech_device_info *info)
312 {
313 	return info->fw_version & 0x001000;
314 }
315 
316 /*
317  * Interpret complete data packets and report absolute mode input events for
318  * hardware version 1. (4 byte packets)
319  */
320 static void elantech_report_absolute_v1(struct psmouse *psmouse)
321 {
322 	struct input_dev *dev = psmouse->dev;
323 	struct elantech_data *etd = psmouse->private;
324 	unsigned char *packet = psmouse->packet;
325 	int fingers;
326 
327 	if (etd->info.fw_version < 0x020000) {
328 		/*
329 		 * byte 0:  D   U  p1  p2   1  p3   R   L
330 		 * byte 1:  f   0  th  tw  x9  x8  y9  y8
331 		 */
332 		fingers = ((packet[1] & 0x80) >> 7) +
333 				((packet[1] & 0x30) >> 4);
334 	} else {
335 		/*
336 		 * byte 0: n1  n0  p2  p1   1  p3   R   L
337 		 * byte 1:  0   0   0   0  x9  x8  y9  y8
338 		 */
339 		fingers = (packet[0] & 0xc0) >> 6;
340 	}
341 
342 	if (etd->info.jumpy_cursor) {
343 		if (fingers != 1) {
344 			etd->single_finger_reports = 0;
345 		} else if (etd->single_finger_reports < 2) {
346 			/* Discard first 2 reports of one finger, bogus */
347 			etd->single_finger_reports++;
348 			elantech_debug("discarding packet\n");
349 			return;
350 		}
351 	}
352 
353 	input_report_key(dev, BTN_TOUCH, fingers != 0);
354 
355 	/*
356 	 * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
357 	 * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
358 	 */
359 	if (fingers) {
360 		input_report_abs(dev, ABS_X,
361 			((packet[1] & 0x0c) << 6) | packet[2]);
362 		input_report_abs(dev, ABS_Y,
363 			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
364 	}
365 
366 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
367 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
368 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
369 
370 	psmouse_report_standard_buttons(dev, packet[0]);
371 
372 	if (etd->info.fw_version < 0x020000 &&
373 	    (etd->info.capabilities[0] & ETP_CAP_HAS_ROCKER)) {
374 		/* rocker up */
375 		input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
376 		/* rocker down */
377 		input_report_key(dev, BTN_BACK, packet[0] & 0x80);
378 	}
379 
380 	input_sync(dev);
381 }
382 
383 static void elantech_set_slot(struct input_dev *dev, int slot, bool active,
384 			      unsigned int x, unsigned int y)
385 {
386 	input_mt_slot(dev, slot);
387 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
388 	if (active) {
389 		input_report_abs(dev, ABS_MT_POSITION_X, x);
390 		input_report_abs(dev, ABS_MT_POSITION_Y, y);
391 	}
392 }
393 
394 /* x1 < x2 and y1 < y2 when two fingers, x = y = 0 when not pressed */
395 static void elantech_report_semi_mt_data(struct input_dev *dev,
396 					 unsigned int num_fingers,
397 					 unsigned int x1, unsigned int y1,
398 					 unsigned int x2, unsigned int y2)
399 {
400 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
401 	elantech_set_slot(dev, 1, num_fingers >= 2, x2, y2);
402 }
403 
404 /*
405  * Interpret complete data packets and report absolute mode input events for
406  * hardware version 2. (6 byte packets)
407  */
408 static void elantech_report_absolute_v2(struct psmouse *psmouse)
409 {
410 	struct elantech_data *etd = psmouse->private;
411 	struct input_dev *dev = psmouse->dev;
412 	unsigned char *packet = psmouse->packet;
413 	unsigned int fingers, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
414 	unsigned int width = 0, pres = 0;
415 
416 	/* byte 0: n1  n0   .   .   .   .   R   L */
417 	fingers = (packet[0] & 0xc0) >> 6;
418 
419 	switch (fingers) {
420 	case 3:
421 		/*
422 		 * Same as one finger, except report of more than 3 fingers:
423 		 * byte 3:  n4  .   w1  w0   .   .   .   .
424 		 */
425 		if (packet[3] & 0x80)
426 			fingers = 4;
427 		fallthrough;
428 	case 1:
429 		/*
430 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
431 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
432 		 */
433 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
434 		/*
435 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
436 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
437 		 */
438 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
439 
440 		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
441 		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
442 		break;
443 
444 	case 2:
445 		/*
446 		 * The coordinate of each finger is reported separately
447 		 * with a lower resolution for two finger touches:
448 		 * byte 0:  .   .  ay8 ax8  .   .   .   .
449 		 * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
450 		 */
451 		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
452 		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
453 		y1 = etd->y_max -
454 			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
455 		/*
456 		 * byte 3:  .   .  by8 bx8  .   .   .   .
457 		 * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
458 		 */
459 		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
460 		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
461 		y2 = etd->y_max -
462 			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
463 
464 		/* Unknown so just report sensible values */
465 		pres = 127;
466 		width = 7;
467 		break;
468 	}
469 
470 	input_report_key(dev, BTN_TOUCH, fingers != 0);
471 	if (fingers != 0) {
472 		input_report_abs(dev, ABS_X, x1);
473 		input_report_abs(dev, ABS_Y, y1);
474 	}
475 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
476 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
477 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
478 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
479 	input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);
480 	psmouse_report_standard_buttons(dev, packet[0]);
481 	if (etd->info.reports_pressure) {
482 		input_report_abs(dev, ABS_PRESSURE, pres);
483 		input_report_abs(dev, ABS_TOOL_WIDTH, width);
484 	}
485 
486 	input_sync(dev);
487 }
488 
489 static void elantech_report_trackpoint(struct psmouse *psmouse,
490 				       int packet_type)
491 {
492 	/*
493 	 * byte 0:  0   0  sx  sy   0   M   R   L
494 	 * byte 1:~sx   0   0   0   0   0   0   0
495 	 * byte 2:~sy   0   0   0   0   0   0   0
496 	 * byte 3:  0   0 ~sy ~sx   0   1   1   0
497 	 * byte 4: x7  x6  x5  x4  x3  x2  x1  x0
498 	 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
499 	 *
500 	 * x and y are written in two's complement spread
501 	 * over 9 bits with sx/sy the relative top bit and
502 	 * x7..x0 and y7..y0 the lower bits.
503 	 * The sign of y is opposite to what the input driver
504 	 * expects for a relative movement
505 	 */
506 
507 	struct elantech_data *etd = psmouse->private;
508 	struct input_dev *tp_dev = etd->tp_dev;
509 	unsigned char *packet = psmouse->packet;
510 	int x, y;
511 	u32 t;
512 
513 	t = get_unaligned_le32(&packet[0]);
514 
515 	switch (t & ~7U) {
516 	case 0x06000030U:
517 	case 0x16008020U:
518 	case 0x26800010U:
519 	case 0x36808000U:
520 
521 		/*
522 		 * This firmware misreport coordinates for trackpoint
523 		 * occasionally. Discard packets outside of [-127, 127] range
524 		 * to prevent cursor jumps.
525 		 */
526 		if (packet[4] == 0x80 || packet[5] == 0x80 ||
527 		    packet[1] >> 7 == packet[4] >> 7 ||
528 		    packet[2] >> 7 == packet[5] >> 7) {
529 			elantech_debug("discarding packet [%6ph]\n", packet);
530 			break;
531 
532 		}
533 		x = packet[4] - (int)((packet[1]^0x80) << 1);
534 		y = (int)((packet[2]^0x80) << 1) - packet[5];
535 
536 		psmouse_report_standard_buttons(tp_dev, packet[0]);
537 
538 		input_report_rel(tp_dev, REL_X, x);
539 		input_report_rel(tp_dev, REL_Y, y);
540 
541 		input_sync(tp_dev);
542 
543 		break;
544 
545 	default:
546 		/* Dump unexpected packet sequences if debug=1 (default) */
547 		if (etd->info.debug == 1)
548 			elantech_packet_dump(psmouse);
549 
550 		break;
551 	}
552 }
553 
554 /*
555  * Interpret complete data packets and report absolute mode input events for
556  * hardware version 3. (12 byte packets for two fingers)
557  */
558 static void elantech_report_absolute_v3(struct psmouse *psmouse,
559 					int packet_type)
560 {
561 	struct input_dev *dev = psmouse->dev;
562 	struct elantech_data *etd = psmouse->private;
563 	unsigned char *packet = psmouse->packet;
564 	unsigned int fingers = 0, x1 = 0, y1 = 0, x2 = 0, y2 = 0;
565 	unsigned int width = 0, pres = 0;
566 
567 	/* byte 0: n1  n0   .   .   .   .   R   L */
568 	fingers = (packet[0] & 0xc0) >> 6;
569 
570 	switch (fingers) {
571 	case 3:
572 	case 1:
573 		/*
574 		 * byte 1:  .   .   .   .  x11 x10 x9  x8
575 		 * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
576 		 */
577 		x1 = ((packet[1] & 0x0f) << 8) | packet[2];
578 		/*
579 		 * byte 4:  .   .   .   .  y11 y10 y9  y8
580 		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
581 		 */
582 		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
583 		break;
584 
585 	case 2:
586 		if (packet_type == PACKET_V3_HEAD) {
587 			/*
588 			 * byte 1:   .    .    .    .  ax11 ax10 ax9  ax8
589 			 * byte 2: ax7  ax6  ax5  ax4  ax3  ax2  ax1  ax0
590 			 */
591 			etd->mt[0].x = ((packet[1] & 0x0f) << 8) | packet[2];
592 			/*
593 			 * byte 4:   .    .    .    .  ay11 ay10 ay9  ay8
594 			 * byte 5: ay7  ay6  ay5  ay4  ay3  ay2  ay1  ay0
595 			 */
596 			etd->mt[0].y = etd->y_max -
597 				(((packet[4] & 0x0f) << 8) | packet[5]);
598 			/*
599 			 * wait for next packet
600 			 */
601 			return;
602 		}
603 
604 		/* packet_type == PACKET_V3_TAIL */
605 		x1 = etd->mt[0].x;
606 		y1 = etd->mt[0].y;
607 		x2 = ((packet[1] & 0x0f) << 8) | packet[2];
608 		y2 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
609 		break;
610 	}
611 
612 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
613 	width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
614 
615 	input_report_key(dev, BTN_TOUCH, fingers != 0);
616 	if (fingers != 0) {
617 		input_report_abs(dev, ABS_X, x1);
618 		input_report_abs(dev, ABS_Y, y1);
619 	}
620 	elantech_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);
621 	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
622 	input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
623 	input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
624 
625 	/* For clickpads map both buttons to BTN_LEFT */
626 	if (elantech_is_buttonpad(&etd->info))
627 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
628 	else
629 		psmouse_report_standard_buttons(dev, packet[0]);
630 
631 	input_report_abs(dev, ABS_PRESSURE, pres);
632 	input_report_abs(dev, ABS_TOOL_WIDTH, width);
633 
634 	input_sync(dev);
635 }
636 
637 static void elantech_input_sync_v4(struct psmouse *psmouse)
638 {
639 	struct input_dev *dev = psmouse->dev;
640 	struct elantech_data *etd = psmouse->private;
641 	unsigned char *packet = psmouse->packet;
642 
643 	/* For clickpads map both buttons to BTN_LEFT */
644 	if (elantech_is_buttonpad(&etd->info))
645 		input_report_key(dev, BTN_LEFT, packet[0] & 0x03);
646 	else
647 		psmouse_report_standard_buttons(dev, packet[0]);
648 
649 	input_mt_report_pointer_emulation(dev, true);
650 	input_sync(dev);
651 }
652 
653 static void process_packet_status_v4(struct psmouse *psmouse)
654 {
655 	struct input_dev *dev = psmouse->dev;
656 	unsigned char *packet = psmouse->packet;
657 	unsigned fingers;
658 	int i;
659 
660 	/* notify finger state change */
661 	fingers = packet[1] & 0x1f;
662 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
663 		if ((fingers & (1 << i)) == 0) {
664 			input_mt_slot(dev, i);
665 			input_mt_report_slot_state(dev, MT_TOOL_FINGER, false);
666 		}
667 	}
668 
669 	elantech_input_sync_v4(psmouse);
670 }
671 
672 static void process_packet_head_v4(struct psmouse *psmouse)
673 {
674 	struct input_dev *dev = psmouse->dev;
675 	struct elantech_data *etd = psmouse->private;
676 	unsigned char *packet = psmouse->packet;
677 	int id;
678 	int pres, traces;
679 
680 	id = ((packet[3] & 0xe0) >> 5) - 1;
681 	if (id < 0 || id >= ETP_MAX_FINGERS)
682 		return;
683 
684 	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
685 	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
686 	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
687 	traces = (packet[0] & 0xf0) >> 4;
688 
689 	input_mt_slot(dev, id);
690 	input_mt_report_slot_state(dev, MT_TOOL_FINGER, true);
691 
692 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
693 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
694 	input_report_abs(dev, ABS_MT_PRESSURE, pres);
695 	input_report_abs(dev, ABS_MT_TOUCH_MAJOR, traces * etd->width);
696 	/* report this for backwards compatibility */
697 	input_report_abs(dev, ABS_TOOL_WIDTH, traces);
698 
699 	elantech_input_sync_v4(psmouse);
700 }
701 
702 static void process_packet_motion_v4(struct psmouse *psmouse)
703 {
704 	struct input_dev *dev = psmouse->dev;
705 	struct elantech_data *etd = psmouse->private;
706 	unsigned char *packet = psmouse->packet;
707 	int weight, delta_x1 = 0, delta_y1 = 0, delta_x2 = 0, delta_y2 = 0;
708 	int id, sid;
709 
710 	id = ((packet[0] & 0xe0) >> 5) - 1;
711 	if (id < 0 || id >= ETP_MAX_FINGERS)
712 		return;
713 
714 	sid = ((packet[3] & 0xe0) >> 5) - 1;
715 	weight = (packet[0] & 0x10) ? ETP_WEIGHT_VALUE : 1;
716 	/*
717 	 * Motion packets give us the delta of x, y values of specific fingers,
718 	 * but in two's complement. Let the compiler do the conversion for us.
719 	 * Also _enlarge_ the numbers to int, in case of overflow.
720 	 */
721 	delta_x1 = (signed char)packet[1];
722 	delta_y1 = (signed char)packet[2];
723 	delta_x2 = (signed char)packet[4];
724 	delta_y2 = (signed char)packet[5];
725 
726 	etd->mt[id].x += delta_x1 * weight;
727 	etd->mt[id].y -= delta_y1 * weight;
728 	input_mt_slot(dev, id);
729 	input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[id].x);
730 	input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[id].y);
731 
732 	if (sid >= 0 && sid < ETP_MAX_FINGERS) {
733 		etd->mt[sid].x += delta_x2 * weight;
734 		etd->mt[sid].y -= delta_y2 * weight;
735 		input_mt_slot(dev, sid);
736 		input_report_abs(dev, ABS_MT_POSITION_X, etd->mt[sid].x);
737 		input_report_abs(dev, ABS_MT_POSITION_Y, etd->mt[sid].y);
738 	}
739 
740 	elantech_input_sync_v4(psmouse);
741 }
742 
743 static void elantech_report_absolute_v4(struct psmouse *psmouse,
744 					int packet_type)
745 {
746 	switch (packet_type) {
747 	case PACKET_V4_STATUS:
748 		process_packet_status_v4(psmouse);
749 		break;
750 
751 	case PACKET_V4_HEAD:
752 		process_packet_head_v4(psmouse);
753 		break;
754 
755 	case PACKET_V4_MOTION:
756 		process_packet_motion_v4(psmouse);
757 		break;
758 
759 	case PACKET_UNKNOWN:
760 	default:
761 		/* impossible to get here */
762 		break;
763 	}
764 }
765 
766 static int elantech_packet_check_v1(struct psmouse *psmouse)
767 {
768 	struct elantech_data *etd = psmouse->private;
769 	unsigned char *packet = psmouse->packet;
770 	unsigned char p1, p2, p3;
771 
772 	/* Parity bits are placed differently */
773 	if (etd->info.fw_version < 0x020000) {
774 		/* byte 0:  D   U  p1  p2   1  p3   R   L */
775 		p1 = (packet[0] & 0x20) >> 5;
776 		p2 = (packet[0] & 0x10) >> 4;
777 	} else {
778 		/* byte 0: n1  n0  p2  p1   1  p3   R   L */
779 		p1 = (packet[0] & 0x10) >> 4;
780 		p2 = (packet[0] & 0x20) >> 5;
781 	}
782 
783 	p3 = (packet[0] & 0x04) >> 2;
784 
785 	return etd->parity[packet[1]] == p1 &&
786 	       etd->parity[packet[2]] == p2 &&
787 	       etd->parity[packet[3]] == p3;
788 }
789 
790 static int elantech_debounce_check_v2(struct psmouse *psmouse)
791 {
792         /*
793          * When we encounter packet that matches this exactly, it means the
794          * hardware is in debounce status. Just ignore the whole packet.
795          */
796 	static const u8 debounce_packet[] = {
797 		0x84, 0xff, 0xff, 0x02, 0xff, 0xff
798 	};
799         unsigned char *packet = psmouse->packet;
800 
801         return !memcmp(packet, debounce_packet, sizeof(debounce_packet));
802 }
803 
804 static int elantech_packet_check_v2(struct psmouse *psmouse)
805 {
806 	struct elantech_data *etd = psmouse->private;
807 	unsigned char *packet = psmouse->packet;
808 
809 	/*
810 	 * V2 hardware has two flavors. Older ones that do not report pressure,
811 	 * and newer ones that reports pressure and width. With newer ones, all
812 	 * packets (1, 2, 3 finger touch) have the same constant bits. With
813 	 * older ones, 1/3 finger touch packets and 2 finger touch packets
814 	 * have different constant bits.
815 	 * With all three cases, if the constant bits are not exactly what I
816 	 * expected, I consider them invalid.
817 	 */
818 	if (etd->info.reports_pressure)
819 		return (packet[0] & 0x0c) == 0x04 &&
820 		       (packet[3] & 0x0f) == 0x02;
821 
822 	if ((packet[0] & 0xc0) == 0x80)
823 		return (packet[0] & 0x0c) == 0x0c &&
824 		       (packet[3] & 0x0e) == 0x08;
825 
826 	return (packet[0] & 0x3c) == 0x3c &&
827 	       (packet[1] & 0xf0) == 0x00 &&
828 	       (packet[3] & 0x3e) == 0x38 &&
829 	       (packet[4] & 0xf0) == 0x00;
830 }
831 
832 /*
833  * We check the constant bits to determine what packet type we get,
834  * so packet checking is mandatory for v3 and later hardware.
835  */
836 static int elantech_packet_check_v3(struct psmouse *psmouse)
837 {
838 	struct elantech_data *etd = psmouse->private;
839 	static const u8 debounce_packet[] = {
840 		0xc4, 0xff, 0xff, 0x02, 0xff, 0xff
841 	};
842 	unsigned char *packet = psmouse->packet;
843 
844 	/*
845 	 * check debounce first, it has the same signature in byte 0
846 	 * and byte 3 as PACKET_V3_HEAD.
847 	 */
848 	if (!memcmp(packet, debounce_packet, sizeof(debounce_packet)))
849 		return PACKET_DEBOUNCE;
850 
851 	/*
852 	 * If the hardware flag 'crc_enabled' is set the packets have
853 	 * different signatures.
854 	 */
855 	if (etd->info.crc_enabled) {
856 		if ((packet[3] & 0x09) == 0x08)
857 			return PACKET_V3_HEAD;
858 
859 		if ((packet[3] & 0x09) == 0x09)
860 			return PACKET_V3_TAIL;
861 	} else {
862 		if ((packet[0] & 0x0c) == 0x04 && (packet[3] & 0xcf) == 0x02)
863 			return PACKET_V3_HEAD;
864 
865 		if ((packet[0] & 0x0c) == 0x0c && (packet[3] & 0xce) == 0x0c)
866 			return PACKET_V3_TAIL;
867 		if ((packet[3] & 0x0f) == 0x06)
868 			return PACKET_TRACKPOINT;
869 	}
870 
871 	return PACKET_UNKNOWN;
872 }
873 
874 static int elantech_packet_check_v4(struct psmouse *psmouse)
875 {
876 	struct elantech_data *etd = psmouse->private;
877 	unsigned char *packet = psmouse->packet;
878 	unsigned char packet_type = packet[3] & 0x03;
879 	unsigned int ic_version;
880 	bool sanity_check;
881 
882 	if (etd->tp_dev && (packet[3] & 0x0f) == 0x06)
883 		return PACKET_TRACKPOINT;
884 
885 	/* This represents the version of IC body. */
886 	ic_version = (etd->info.fw_version & 0x0f0000) >> 16;
887 
888 	/*
889 	 * Sanity check based on the constant bits of a packet.
890 	 * The constant bits change depending on the value of
891 	 * the hardware flag 'crc_enabled' and the version of
892 	 * the IC body, but are the same for every packet,
893 	 * regardless of the type.
894 	 */
895 	if (etd->info.crc_enabled)
896 		sanity_check = ((packet[3] & 0x08) == 0x00);
897 	else if (ic_version == 7 && etd->info.samples[1] == 0x2A)
898 		sanity_check = ((packet[3] & 0x1c) == 0x10);
899 	else
900 		sanity_check = ((packet[0] & 0x08) == 0x00 &&
901 				(packet[3] & 0x1c) == 0x10);
902 
903 	if (!sanity_check)
904 		return PACKET_UNKNOWN;
905 
906 	switch (packet_type) {
907 	case 0:
908 		return PACKET_V4_STATUS;
909 
910 	case 1:
911 		return PACKET_V4_HEAD;
912 
913 	case 2:
914 		return PACKET_V4_MOTION;
915 	}
916 
917 	return PACKET_UNKNOWN;
918 }
919 
920 /*
921  * Process byte stream from mouse and handle complete packets
922  */
923 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
924 {
925 	struct elantech_data *etd = psmouse->private;
926 	int packet_type;
927 
928 	if (psmouse->pktcnt < psmouse->pktsize)
929 		return PSMOUSE_GOOD_DATA;
930 
931 	if (etd->info.debug > 1)
932 		elantech_packet_dump(psmouse);
933 
934 	switch (etd->info.hw_version) {
935 	case 1:
936 		if (etd->info.paritycheck && !elantech_packet_check_v1(psmouse))
937 			return PSMOUSE_BAD_DATA;
938 
939 		elantech_report_absolute_v1(psmouse);
940 		break;
941 
942 	case 2:
943 		/* ignore debounce */
944 		if (elantech_debounce_check_v2(psmouse))
945 			return PSMOUSE_FULL_PACKET;
946 
947 		if (etd->info.paritycheck && !elantech_packet_check_v2(psmouse))
948 			return PSMOUSE_BAD_DATA;
949 
950 		elantech_report_absolute_v2(psmouse);
951 		break;
952 
953 	case 3:
954 		packet_type = elantech_packet_check_v3(psmouse);
955 		switch (packet_type) {
956 		case PACKET_UNKNOWN:
957 			return PSMOUSE_BAD_DATA;
958 
959 		case PACKET_DEBOUNCE:
960 			/* ignore debounce */
961 			break;
962 
963 		case PACKET_TRACKPOINT:
964 			elantech_report_trackpoint(psmouse, packet_type);
965 			break;
966 
967 		default:
968 			elantech_report_absolute_v3(psmouse, packet_type);
969 			break;
970 		}
971 
972 		break;
973 
974 	case 4:
975 		packet_type = elantech_packet_check_v4(psmouse);
976 		switch (packet_type) {
977 		case PACKET_UNKNOWN:
978 			return PSMOUSE_BAD_DATA;
979 
980 		case PACKET_TRACKPOINT:
981 			elantech_report_trackpoint(psmouse, packet_type);
982 			break;
983 
984 		default:
985 			elantech_report_absolute_v4(psmouse, packet_type);
986 			break;
987 		}
988 
989 		break;
990 	}
991 
992 	return PSMOUSE_FULL_PACKET;
993 }
994 
995 /*
996  * This writes the reg_07 value again to the hardware at the end of every
997  * set_rate call because the register loses its value. reg_07 allows setting
998  * absolute mode on v4 hardware
999  */
1000 static void elantech_set_rate_restore_reg_07(struct psmouse *psmouse,
1001 		unsigned int rate)
1002 {
1003 	struct elantech_data *etd = psmouse->private;
1004 
1005 	etd->original_set_rate(psmouse, rate);
1006 	if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
1007 		psmouse_err(psmouse, "restoring reg_07 failed\n");
1008 }
1009 
1010 /*
1011  * Put the touchpad into absolute mode
1012  */
1013 static int elantech_set_absolute_mode(struct psmouse *psmouse)
1014 {
1015 	struct elantech_data *etd = psmouse->private;
1016 	unsigned char val;
1017 	int tries = ETP_READ_BACK_TRIES;
1018 	int rc = 0;
1019 
1020 	switch (etd->info.hw_version) {
1021 	case 1:
1022 		etd->reg_10 = 0x16;
1023 		etd->reg_11 = 0x8f;
1024 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
1025 		    elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
1026 			rc = -1;
1027 		}
1028 		break;
1029 
1030 	case 2:
1031 					/* Windows driver values */
1032 		etd->reg_10 = 0x54;
1033 		etd->reg_11 = 0x88;	/* 0x8a */
1034 		etd->reg_21 = 0x60;	/* 0x00 */
1035 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
1036 		    elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
1037 		    elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
1038 			rc = -1;
1039 		}
1040 		break;
1041 
1042 	case 3:
1043 		if (etd->info.set_hw_resolution)
1044 			etd->reg_10 = 0x0b;
1045 		else
1046 			etd->reg_10 = 0x01;
1047 
1048 		if (elantech_write_reg(psmouse, 0x10, etd->reg_10))
1049 			rc = -1;
1050 
1051 		break;
1052 
1053 	case 4:
1054 		etd->reg_07 = 0x01;
1055 		if (elantech_write_reg(psmouse, 0x07, etd->reg_07))
1056 			rc = -1;
1057 
1058 		goto skip_readback_reg_10; /* v4 has no reg 0x10 to read */
1059 	}
1060 
1061 	if (rc == 0) {
1062 		/*
1063 		 * Read back reg 0x10. For hardware version 1 we must make
1064 		 * sure the absolute mode bit is set. For hardware version 2
1065 		 * the touchpad is probably initializing and not ready until
1066 		 * we read back the value we just wrote.
1067 		 */
1068 		do {
1069 			rc = elantech_read_reg(psmouse, 0x10, &val);
1070 			if (rc == 0)
1071 				break;
1072 			tries--;
1073 			elantech_debug("retrying read (%d).\n", tries);
1074 			msleep(ETP_READ_BACK_DELAY);
1075 		} while (tries > 0);
1076 
1077 		if (rc) {
1078 			psmouse_err(psmouse,
1079 				    "failed to read back register 0x10.\n");
1080 		} else if (etd->info.hw_version == 1 &&
1081 			   !(val & ETP_R10_ABSOLUTE_MODE)) {
1082 			psmouse_err(psmouse,
1083 				    "touchpad refuses to switch to absolute mode.\n");
1084 			rc = -1;
1085 		}
1086 	}
1087 
1088  skip_readback_reg_10:
1089 	if (rc)
1090 		psmouse_err(psmouse, "failed to initialise registers.\n");
1091 
1092 	return rc;
1093 }
1094 
1095 /*
1096  * (value from firmware) * 10 + 790 = dpi
1097  * we also have to convert dpi to dots/mm (*10/254 to avoid floating point)
1098  */
1099 static unsigned int elantech_convert_res(unsigned int val)
1100 {
1101 	return (val * 10 + 790) * 10 / 254;
1102 }
1103 
1104 static int elantech_get_resolution_v4(struct psmouse *psmouse,
1105 				      unsigned int *x_res,
1106 				      unsigned int *y_res,
1107 				      unsigned int *bus)
1108 {
1109 	unsigned char param[3];
1110 
1111 	if (elantech_send_cmd(psmouse, ETP_RESOLUTION_QUERY, param))
1112 		return -1;
1113 
1114 	*x_res = elantech_convert_res(param[1] & 0x0f);
1115 	*y_res = elantech_convert_res((param[1] & 0xf0) >> 4);
1116 	*bus = param[2];
1117 
1118 	return 0;
1119 }
1120 
1121 static void elantech_set_buttonpad_prop(struct psmouse *psmouse)
1122 {
1123 	struct input_dev *dev = psmouse->dev;
1124 	struct elantech_data *etd = psmouse->private;
1125 
1126 	if (elantech_is_buttonpad(&etd->info)) {
1127 		__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
1128 		__clear_bit(BTN_RIGHT, dev->keybit);
1129 	}
1130 }
1131 
1132 /*
1133  * Some hw_version 4 models do have a middle button
1134  */
1135 static const struct dmi_system_id elantech_dmi_has_middle_button[] = {
1136 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1137 	{
1138 		/* Fujitsu H730 has a middle button */
1139 		.matches = {
1140 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1141 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1142 		},
1143 	},
1144 	{
1145 		/* Fujitsu H760 also has a middle button */
1146 		.matches = {
1147 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1148 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1149 		},
1150 	},
1151 	{
1152 		/* Fujitsu H780 also has a middle button */
1153 		.matches = {
1154 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1155 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H780"),
1156 		},
1157 	},
1158 #endif
1159 	{ }
1160 };
1161 
1162 /*
1163  * Set the appropriate event bits for the input subsystem
1164  */
1165 static int elantech_set_input_params(struct psmouse *psmouse)
1166 {
1167 	struct input_dev *dev = psmouse->dev;
1168 	struct elantech_data *etd = psmouse->private;
1169 	struct elantech_device_info *info = &etd->info;
1170 	unsigned int x_min = info->x_min, y_min = info->y_min,
1171 		     x_max = info->x_max, y_max = info->y_max,
1172 		     width = info->width;
1173 
1174 	__set_bit(INPUT_PROP_POINTER, dev->propbit);
1175 	__set_bit(EV_KEY, dev->evbit);
1176 	__set_bit(EV_ABS, dev->evbit);
1177 	__clear_bit(EV_REL, dev->evbit);
1178 
1179 	__set_bit(BTN_LEFT, dev->keybit);
1180 	if (info->has_middle_button)
1181 		__set_bit(BTN_MIDDLE, dev->keybit);
1182 	__set_bit(BTN_RIGHT, dev->keybit);
1183 
1184 	__set_bit(BTN_TOUCH, dev->keybit);
1185 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
1186 	__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
1187 	__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
1188 
1189 	switch (info->hw_version) {
1190 	case 1:
1191 		/* Rocker button */
1192 		if (info->fw_version < 0x020000 &&
1193 		    (info->capabilities[0] & ETP_CAP_HAS_ROCKER)) {
1194 			__set_bit(BTN_FORWARD, dev->keybit);
1195 			__set_bit(BTN_BACK, dev->keybit);
1196 		}
1197 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1198 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1199 		break;
1200 
1201 	case 2:
1202 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1203 		__set_bit(INPUT_PROP_SEMI_MT, dev->propbit);
1204 		fallthrough;
1205 	case 3:
1206 		if (info->hw_version == 3)
1207 			elantech_set_buttonpad_prop(psmouse);
1208 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1209 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1210 		if (info->reports_pressure) {
1211 			input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1212 					     ETP_PMAX_V2, 0, 0);
1213 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1214 					     ETP_WMAX_V2, 0, 0);
1215 		}
1216 		input_mt_init_slots(dev, 2, INPUT_MT_SEMI_MT);
1217 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1218 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1219 		break;
1220 
1221 	case 4:
1222 		elantech_set_buttonpad_prop(psmouse);
1223 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);
1224 		/* For X to recognize me as touchpad. */
1225 		input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
1226 		input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
1227 		/*
1228 		 * range of pressure and width is the same as v2,
1229 		 * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
1230 		 */
1231 		input_set_abs_params(dev, ABS_PRESSURE, ETP_PMIN_V2,
1232 				     ETP_PMAX_V2, 0, 0);
1233 		input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
1234 				     ETP_WMAX_V2, 0, 0);
1235 		/* Multitouch capable pad, up to 5 fingers. */
1236 		input_mt_init_slots(dev, ETP_MAX_FINGERS, 0);
1237 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
1238 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
1239 		input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
1240 				     ETP_PMAX_V2, 0, 0);
1241 		/*
1242 		 * The firmware reports how many trace lines the finger spans,
1243 		 * convert to surface unit as Protocol-B requires.
1244 		 */
1245 		input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 0,
1246 				     ETP_WMAX_V2 * width, 0, 0);
1247 		break;
1248 	}
1249 
1250 	input_abs_set_res(dev, ABS_X, info->x_res);
1251 	input_abs_set_res(dev, ABS_Y, info->y_res);
1252 	if (info->hw_version > 1) {
1253 		input_abs_set_res(dev, ABS_MT_POSITION_X, info->x_res);
1254 		input_abs_set_res(dev, ABS_MT_POSITION_Y, info->y_res);
1255 	}
1256 
1257 	etd->y_max = y_max;
1258 	etd->width = width;
1259 
1260 	return 0;
1261 }
1262 
1263 struct elantech_attr_data {
1264 	size_t		field_offset;
1265 	unsigned char	reg;
1266 };
1267 
1268 /*
1269  * Display a register value by reading a sysfs entry
1270  */
1271 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
1272 					char *buf)
1273 {
1274 	struct elantech_data *etd = psmouse->private;
1275 	struct elantech_attr_data *attr = data;
1276 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1277 	int rc = 0;
1278 
1279 	if (attr->reg)
1280 		rc = elantech_read_reg(psmouse, attr->reg, reg);
1281 
1282 	return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
1283 }
1284 
1285 /*
1286  * Write a register value by writing a sysfs entry
1287  */
1288 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
1289 				     void *data, const char *buf, size_t count)
1290 {
1291 	struct elantech_data *etd = psmouse->private;
1292 	struct elantech_attr_data *attr = data;
1293 	unsigned char *reg = (unsigned char *) etd + attr->field_offset;
1294 	unsigned char value;
1295 	int err;
1296 
1297 	err = kstrtou8(buf, 16, &value);
1298 	if (err)
1299 		return err;
1300 
1301 	/* Do we need to preserve some bits for version 2 hardware too? */
1302 	if (etd->info.hw_version == 1) {
1303 		if (attr->reg == 0x10)
1304 			/* Force absolute mode always on */
1305 			value |= ETP_R10_ABSOLUTE_MODE;
1306 		else if (attr->reg == 0x11)
1307 			/* Force 4 byte mode always on */
1308 			value |= ETP_R11_4_BYTE_MODE;
1309 	}
1310 
1311 	if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
1312 		*reg = value;
1313 
1314 	return count;
1315 }
1316 
1317 #define ELANTECH_INT_ATTR(_name, _register)				\
1318 	static struct elantech_attr_data elantech_attr_##_name = {	\
1319 		.field_offset = offsetof(struct elantech_data, _name),	\
1320 		.reg = _register,					\
1321 	};								\
1322 	PSMOUSE_DEFINE_ATTR(_name, 0644,				\
1323 			    &elantech_attr_##_name,			\
1324 			    elantech_show_int_attr,			\
1325 			    elantech_set_int_attr)
1326 
1327 #define ELANTECH_INFO_ATTR(_name)					       \
1328 	static struct elantech_attr_data elantech_attr_##_name = {	       \
1329 		.field_offset = offsetof(struct elantech_data, info) +	       \
1330 				offsetof(struct elantech_device_info, _name),  \
1331 		.reg = 0,						       \
1332 	};								       \
1333 	PSMOUSE_DEFINE_ATTR(_name, 0644,				       \
1334 			    &elantech_attr_##_name,			       \
1335 			    elantech_show_int_attr,			       \
1336 			    elantech_set_int_attr)
1337 
1338 ELANTECH_INT_ATTR(reg_07, 0x07);
1339 ELANTECH_INT_ATTR(reg_10, 0x10);
1340 ELANTECH_INT_ATTR(reg_11, 0x11);
1341 ELANTECH_INT_ATTR(reg_20, 0x20);
1342 ELANTECH_INT_ATTR(reg_21, 0x21);
1343 ELANTECH_INT_ATTR(reg_22, 0x22);
1344 ELANTECH_INT_ATTR(reg_23, 0x23);
1345 ELANTECH_INT_ATTR(reg_24, 0x24);
1346 ELANTECH_INT_ATTR(reg_25, 0x25);
1347 ELANTECH_INT_ATTR(reg_26, 0x26);
1348 ELANTECH_INFO_ATTR(debug);
1349 ELANTECH_INFO_ATTR(paritycheck);
1350 ELANTECH_INFO_ATTR(crc_enabled);
1351 
1352 static struct attribute *elantech_attrs[] = {
1353 	&psmouse_attr_reg_07.dattr.attr,
1354 	&psmouse_attr_reg_10.dattr.attr,
1355 	&psmouse_attr_reg_11.dattr.attr,
1356 	&psmouse_attr_reg_20.dattr.attr,
1357 	&psmouse_attr_reg_21.dattr.attr,
1358 	&psmouse_attr_reg_22.dattr.attr,
1359 	&psmouse_attr_reg_23.dattr.attr,
1360 	&psmouse_attr_reg_24.dattr.attr,
1361 	&psmouse_attr_reg_25.dattr.attr,
1362 	&psmouse_attr_reg_26.dattr.attr,
1363 	&psmouse_attr_debug.dattr.attr,
1364 	&psmouse_attr_paritycheck.dattr.attr,
1365 	&psmouse_attr_crc_enabled.dattr.attr,
1366 	NULL
1367 };
1368 
1369 static const struct attribute_group elantech_attr_group = {
1370 	.attrs = elantech_attrs,
1371 };
1372 
1373 static bool elantech_is_signature_valid(const unsigned char *param)
1374 {
1375 	static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
1376 	int i;
1377 
1378 	if (param[0] == 0)
1379 		return false;
1380 
1381 	if (param[1] == 0)
1382 		return true;
1383 
1384 	/*
1385 	 * Some hw_version >= 4 models have a revision higher then 20. Meaning
1386 	 * that param[2] may be 10 or 20, skip the rates check for these.
1387 	 */
1388 	if ((param[0] & 0x0f) >= 0x06 && (param[1] & 0xaf) == 0x0f &&
1389 	    param[2] < 40)
1390 		return true;
1391 
1392 	for (i = 0; i < ARRAY_SIZE(rates); i++)
1393 		if (param[2] == rates[i])
1394 			return false;
1395 
1396 	return true;
1397 }
1398 
1399 /*
1400  * Use magic knock to detect Elantech touchpad
1401  */
1402 int elantech_detect(struct psmouse *psmouse, bool set_properties)
1403 {
1404 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1405 	unsigned char param[3];
1406 
1407 	ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1408 
1409 	if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
1410 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1411 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1412 	    ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
1413 	    ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1414 		psmouse_dbg(psmouse, "sending Elantech magic knock failed.\n");
1415 		return -1;
1416 	}
1417 
1418 	/*
1419 	 * Report this in case there are Elantech models that use a different
1420 	 * set of magic numbers
1421 	 */
1422 	if (param[0] != 0x3c || param[1] != 0x03 ||
1423 	    (param[2] != 0xc8 && param[2] != 0x00)) {
1424 		psmouse_dbg(psmouse,
1425 			    "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
1426 			    param[0], param[1], param[2]);
1427 		return -1;
1428 	}
1429 
1430 	/*
1431 	 * Query touchpad's firmware version and see if it reports known
1432 	 * value to avoid mis-detection. Logitech mice are known to respond
1433 	 * to Elantech magic knock and there might be more.
1434 	 */
1435 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1436 		psmouse_dbg(psmouse, "failed to query firmware version.\n");
1437 		return -1;
1438 	}
1439 
1440 	psmouse_dbg(psmouse,
1441 		    "Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
1442 		    param[0], param[1], param[2]);
1443 
1444 	if (!elantech_is_signature_valid(param)) {
1445 		psmouse_dbg(psmouse,
1446 			    "Probably not a real Elantech touchpad. Aborting.\n");
1447 		return -1;
1448 	}
1449 
1450 	if (set_properties) {
1451 		psmouse->vendor = "Elantech";
1452 		psmouse->name = "Touchpad";
1453 	}
1454 
1455 	return 0;
1456 }
1457 
1458 /*
1459  * Clean up sysfs entries when disconnecting
1460  */
1461 static void elantech_disconnect(struct psmouse *psmouse)
1462 {
1463 	struct elantech_data *etd = psmouse->private;
1464 
1465 	/*
1466 	 * We might have left a breadcrumb when trying to
1467 	 * set up SMbus companion.
1468 	 */
1469 	psmouse_smbus_cleanup(psmouse);
1470 
1471 	if (etd->tp_dev)
1472 		input_unregister_device(etd->tp_dev);
1473 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
1474 			   &elantech_attr_group);
1475 	kfree(psmouse->private);
1476 	psmouse->private = NULL;
1477 }
1478 
1479 /*
1480  * Some hw_version 4 models fail to properly activate absolute mode on
1481  * resume without going through disable/enable cycle.
1482  */
1483 static const struct dmi_system_id elantech_needs_reenable[] = {
1484 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1485 	{
1486 		/* Lenovo N24 */
1487 		.matches = {
1488 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
1489 			DMI_MATCH(DMI_PRODUCT_NAME, "81AF"),
1490 		},
1491 	},
1492 #endif
1493 	{ }
1494 };
1495 
1496 /*
1497  * Put the touchpad back into absolute mode when reconnecting
1498  */
1499 static int elantech_reconnect(struct psmouse *psmouse)
1500 {
1501 	int err;
1502 
1503 	psmouse_reset(psmouse);
1504 
1505 	if (elantech_detect(psmouse, 0))
1506 		return -1;
1507 
1508 	if (dmi_check_system(elantech_needs_reenable)) {
1509 		err = ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE);
1510 		if (err)
1511 			psmouse_warn(psmouse, "failed to deactivate mouse on %s: %d\n",
1512 				     psmouse->ps2dev.serio->phys, err);
1513 
1514 		err = ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);
1515 		if (err)
1516 			psmouse_warn(psmouse, "failed to reactivate mouse on %s: %d\n",
1517 				     psmouse->ps2dev.serio->phys, err);
1518 	}
1519 
1520 	if (elantech_set_absolute_mode(psmouse)) {
1521 		psmouse_err(psmouse,
1522 			    "failed to put touchpad back into absolute mode.\n");
1523 		return -1;
1524 	}
1525 
1526 	return 0;
1527 }
1528 
1529 /*
1530  * Some hw_version 4 models do not work with crc_disabled
1531  */
1532 static const struct dmi_system_id elantech_dmi_force_crc_enabled[] = {
1533 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1534 	{
1535 		/* Fujitsu H730 does not work with crc_enabled == 0 */
1536 		.matches = {
1537 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1538 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H730"),
1539 		},
1540 	},
1541 	{
1542 		/* Fujitsu H760 does not work with crc_enabled == 0 */
1543 		.matches = {
1544 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1545 			DMI_MATCH(DMI_PRODUCT_NAME, "CELSIUS H760"),
1546 		},
1547 	},
1548 	{
1549 		/* Fujitsu LIFEBOOK E544  does not work with crc_enabled == 0 */
1550 		.matches = {
1551 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1552 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E544"),
1553 		},
1554 	},
1555 	{
1556 		/* Fujitsu LIFEBOOK E546  does not work with crc_enabled == 0 */
1557 		.matches = {
1558 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1559 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E546"),
1560 		},
1561 	},
1562 	{
1563 		/* Fujitsu LIFEBOOK E547 does not work with crc_enabled == 0 */
1564 		.matches = {
1565 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1566 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E547"),
1567 		},
1568 	},
1569 	{
1570 		/* Fujitsu LIFEBOOK E554  does not work with crc_enabled == 0 */
1571 		.matches = {
1572 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1573 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E554"),
1574 		},
1575 	},
1576 	{
1577 		/* Fujitsu LIFEBOOK E556 does not work with crc_enabled == 0 */
1578 		.matches = {
1579 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1580 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E556"),
1581 		},
1582 	},
1583 	{
1584 		/* Fujitsu LIFEBOOK E557 does not work with crc_enabled == 0 */
1585 		.matches = {
1586 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1587 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E557"),
1588 		},
1589 	},
1590 	{
1591 		/* Fujitsu LIFEBOOK U745 does not work with crc_enabled == 0 */
1592 		.matches = {
1593 			DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU"),
1594 			DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK U745"),
1595 		},
1596 	},
1597 #endif
1598 	{ }
1599 };
1600 
1601 /*
1602  * Some hw_version 3 models go into error state when we try to set
1603  * bit 3 and/or bit 1 of r10.
1604  */
1605 static const struct dmi_system_id no_hw_res_dmi_table[] = {
1606 #if defined(CONFIG_DMI) && defined(CONFIG_X86)
1607 	{
1608 		/* Gigabyte U2442 */
1609 		.matches = {
1610 			DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
1611 			DMI_MATCH(DMI_PRODUCT_NAME, "U2442"),
1612 		},
1613 	},
1614 #endif
1615 	{ }
1616 };
1617 
1618 /*
1619  * Change Report id 0x5E to 0x5F.
1620  */
1621 static int elantech_change_report_id(struct psmouse *psmouse)
1622 {
1623 	/*
1624 	 * NOTE: the code is expecting to receive param[] as an array of 3
1625 	 * items (see __ps2_command()), even if in this case only 2 are
1626 	 * actually needed. Make sure the array size is 3 to avoid potential
1627 	 * stack out-of-bound accesses.
1628 	 */
1629 	unsigned char param[3] = { 0x10, 0x03 };
1630 
1631 	if (elantech_write_reg_params(psmouse, 0x7, param) ||
1632 	    elantech_read_reg_params(psmouse, 0x7, param) ||
1633 	    param[0] != 0x10 || param[1] != 0x03) {
1634 		psmouse_err(psmouse, "Unable to change report ID to 0x5f.\n");
1635 		return -EIO;
1636 	}
1637 
1638 	return 0;
1639 }
1640 /*
1641  * determine hardware version and set some properties according to it.
1642  */
1643 static int elantech_set_properties(struct elantech_device_info *info)
1644 {
1645 	/* This represents the version of IC body. */
1646 	info->ic_version = (info->fw_version & 0x0f0000) >> 16;
1647 
1648 	/* Early version of Elan touchpads doesn't obey the rule. */
1649 	if (info->fw_version < 0x020030 || info->fw_version == 0x020600)
1650 		info->hw_version = 1;
1651 	else {
1652 		switch (info->ic_version) {
1653 		case 2:
1654 		case 4:
1655 			info->hw_version = 2;
1656 			break;
1657 		case 5:
1658 			info->hw_version = 3;
1659 			break;
1660 		case 6 ... 15:
1661 			info->hw_version = 4;
1662 			break;
1663 		default:
1664 			return -1;
1665 		}
1666 	}
1667 
1668 	/* Get information pattern for hw_version 4 */
1669 	info->pattern = 0x00;
1670 	if (info->ic_version == 0x0f && (info->fw_version & 0xff) <= 0x02)
1671 		info->pattern = info->fw_version & 0xff;
1672 
1673 	/* decide which send_cmd we're gonna use early */
1674 	info->send_cmd = info->hw_version >= 3 ? elantech_send_cmd :
1675 						 synaptics_send_cmd;
1676 
1677 	/* Turn on packet checking by default */
1678 	info->paritycheck = 1;
1679 
1680 	/*
1681 	 * This firmware suffers from misreporting coordinates when
1682 	 * a touch action starts causing the mouse cursor or scrolled page
1683 	 * to jump. Enable a workaround.
1684 	 */
1685 	info->jumpy_cursor =
1686 		(info->fw_version == 0x020022 || info->fw_version == 0x020600);
1687 
1688 	if (info->hw_version > 1) {
1689 		/* For now show extra debug information */
1690 		info->debug = 1;
1691 
1692 		if (info->fw_version >= 0x020800)
1693 			info->reports_pressure = true;
1694 	}
1695 
1696 	/*
1697 	 * The signatures of v3 and v4 packets change depending on the
1698 	 * value of this hardware flag.
1699 	 */
1700 	info->crc_enabled = (info->fw_version & 0x4000) == 0x4000 ||
1701 			     dmi_check_system(elantech_dmi_force_crc_enabled);
1702 
1703 	/* Enable real hardware resolution on hw_version 3 ? */
1704 	info->set_hw_resolution = !dmi_check_system(no_hw_res_dmi_table);
1705 
1706 	return 0;
1707 }
1708 
1709 static int elantech_query_info(struct psmouse *psmouse,
1710 			       struct elantech_device_info *info)
1711 {
1712 	unsigned char param[3];
1713 	unsigned char traces;
1714 	unsigned char ic_body[3];
1715 
1716 	memset(info, 0, sizeof(*info));
1717 
1718 	/*
1719 	 * Do the version query again so we can store the result
1720 	 */
1721 	if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
1722 		psmouse_err(psmouse, "failed to query firmware version.\n");
1723 		return -EINVAL;
1724 	}
1725 	info->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
1726 
1727 	if (elantech_set_properties(info)) {
1728 		psmouse_err(psmouse, "unknown hardware version, aborting...\n");
1729 		return -EINVAL;
1730 	}
1731 	psmouse_info(psmouse,
1732 		     "assuming hardware version %d (with firmware version 0x%02x%02x%02x)\n",
1733 		     info->hw_version, param[0], param[1], param[2]);
1734 
1735 	if (info->send_cmd(psmouse, ETP_CAPABILITIES_QUERY,
1736 	    info->capabilities)) {
1737 		psmouse_err(psmouse, "failed to query capabilities.\n");
1738 		return -EINVAL;
1739 	}
1740 	psmouse_info(psmouse,
1741 		     "Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
1742 		     info->capabilities[0], info->capabilities[1],
1743 		     info->capabilities[2]);
1744 
1745 	if (info->hw_version != 1) {
1746 		if (info->send_cmd(psmouse, ETP_SAMPLE_QUERY, info->samples)) {
1747 			psmouse_err(psmouse, "failed to query sample data\n");
1748 			return -EINVAL;
1749 		}
1750 		psmouse_info(psmouse,
1751 			     "Elan sample query result %02x, %02x, %02x\n",
1752 			     info->samples[0],
1753 			     info->samples[1],
1754 			     info->samples[2]);
1755 	}
1756 
1757 	if (info->pattern > 0x00 && info->ic_version == 0xf) {
1758 		if (info->send_cmd(psmouse, ETP_ICBODY_QUERY, ic_body)) {
1759 			psmouse_err(psmouse, "failed to query ic body\n");
1760 			return -EINVAL;
1761 		}
1762 		info->ic_version = be16_to_cpup((__be16 *)ic_body);
1763 		psmouse_info(psmouse,
1764 			     "Elan ic body: %#04x, current fw version: %#02x\n",
1765 			     info->ic_version, ic_body[2]);
1766 	}
1767 
1768 	info->product_id = be16_to_cpup((__be16 *)info->samples);
1769 	if (info->pattern == 0x00)
1770 		info->product_id &= 0xff;
1771 
1772 	if (info->samples[1] == 0x74 && info->hw_version == 0x03) {
1773 		/*
1774 		 * This module has a bug which makes absolute mode
1775 		 * unusable, so let's abort so we'll be using standard
1776 		 * PS/2 protocol.
1777 		 */
1778 		psmouse_info(psmouse,
1779 			     "absolute mode broken, forcing standard PS/2 protocol\n");
1780 		return -ENODEV;
1781 	}
1782 
1783 	/* The MSB indicates the presence of the trackpoint */
1784 	info->has_trackpoint = (info->capabilities[0] & 0x80) == 0x80;
1785 
1786 	if (info->has_trackpoint && info->ic_version == 0x0011 &&
1787 	    (info->product_id == 0x08 || info->product_id == 0x09 ||
1788 	     info->product_id == 0x0d || info->product_id == 0x0e)) {
1789 		/*
1790 		 * This module has a bug which makes trackpoint in SMBus
1791 		 * mode return invalid data unless trackpoint is switched
1792 		 * from using 0x5e reports to 0x5f. If we are not able to
1793 		 * make the switch, let's abort initialization so we'll be
1794 		 * using standard PS/2 protocol.
1795 		 */
1796 		if (elantech_change_report_id(psmouse)) {
1797 			psmouse_info(psmouse,
1798 				     "Trackpoint report is broken, forcing standard PS/2 protocol\n");
1799 			return -ENODEV;
1800 		}
1801 	}
1802 
1803 	info->x_res = 31;
1804 	info->y_res = 31;
1805 	if (info->hw_version == 4) {
1806 		if (elantech_get_resolution_v4(psmouse,
1807 					       &info->x_res,
1808 					       &info->y_res,
1809 					       &info->bus)) {
1810 			psmouse_warn(psmouse,
1811 				     "failed to query resolution data.\n");
1812 		}
1813 	}
1814 
1815 	/* query range information */
1816 	switch (info->hw_version) {
1817 	case 1:
1818 		info->x_min = ETP_XMIN_V1;
1819 		info->y_min = ETP_YMIN_V1;
1820 		info->x_max = ETP_XMAX_V1;
1821 		info->y_max = ETP_YMAX_V1;
1822 		break;
1823 
1824 	case 2:
1825 		if (info->fw_version == 0x020800 ||
1826 		    info->fw_version == 0x020b00 ||
1827 		    info->fw_version == 0x020030) {
1828 			info->x_min = ETP_XMIN_V2;
1829 			info->y_min = ETP_YMIN_V2;
1830 			info->x_max = ETP_XMAX_V2;
1831 			info->y_max = ETP_YMAX_V2;
1832 		} else {
1833 			int i;
1834 			int fixed_dpi;
1835 
1836 			i = (info->fw_version > 0x020800 &&
1837 			     info->fw_version < 0x020900) ? 1 : 2;
1838 
1839 			if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1840 				return -EINVAL;
1841 
1842 			fixed_dpi = param[1] & 0x10;
1843 
1844 			if (((info->fw_version >> 16) == 0x14) && fixed_dpi) {
1845 				if (info->send_cmd(psmouse, ETP_SAMPLE_QUERY, param))
1846 					return -EINVAL;
1847 
1848 				info->x_max = (info->capabilities[1] - i) * param[1] / 2;
1849 				info->y_max = (info->capabilities[2] - i) * param[2] / 2;
1850 			} else if (info->fw_version == 0x040216) {
1851 				info->x_max = 819;
1852 				info->y_max = 405;
1853 			} else if (info->fw_version == 0x040219 || info->fw_version == 0x040215) {
1854 				info->x_max = 900;
1855 				info->y_max = 500;
1856 			} else {
1857 				info->x_max = (info->capabilities[1] - i) * 64;
1858 				info->y_max = (info->capabilities[2] - i) * 64;
1859 			}
1860 		}
1861 		break;
1862 
1863 	case 3:
1864 		if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1865 			return -EINVAL;
1866 
1867 		info->x_max = (0x0f & param[0]) << 8 | param[1];
1868 		info->y_max = (0xf0 & param[0]) << 4 | param[2];
1869 		break;
1870 
1871 	case 4:
1872 		if (info->send_cmd(psmouse, ETP_FW_ID_QUERY, param))
1873 			return -EINVAL;
1874 
1875 		info->x_max = (0x0f & param[0]) << 8 | param[1];
1876 		info->y_max = (0xf0 & param[0]) << 4 | param[2];
1877 		traces = info->capabilities[1];
1878 		if ((traces < 2) || (traces > info->x_max))
1879 			return -EINVAL;
1880 
1881 		info->width = info->x_max / (traces - 1);
1882 
1883 		/* column number of traces */
1884 		info->x_traces = traces;
1885 
1886 		/* row number of traces */
1887 		traces = info->capabilities[2];
1888 		if ((traces >= 2) && (traces <= info->y_max))
1889 			info->y_traces = traces;
1890 
1891 		break;
1892 	}
1893 
1894 	/* check for the middle button: DMI matching or new v4 firmwares */
1895 	info->has_middle_button = dmi_check_system(elantech_dmi_has_middle_button) ||
1896 				  (ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version) &&
1897 				   !elantech_is_buttonpad(info));
1898 
1899 	return 0;
1900 }
1901 
1902 #if defined(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)
1903 
1904 /*
1905  * The newest Elantech device can use a secondary bus (over SMBus) which
1906  * provides a better bandwidth and allow a better control of the touchpads.
1907  * This is used to decide if we need to use this bus or not.
1908  */
1909 enum {
1910 	ELANTECH_SMBUS_NOT_SET = -1,
1911 	ELANTECH_SMBUS_OFF,
1912 	ELANTECH_SMBUS_ON,
1913 };
1914 
1915 static int elantech_smbus = IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) ?
1916 		ELANTECH_SMBUS_NOT_SET : ELANTECH_SMBUS_OFF;
1917 module_param_named(elantech_smbus, elantech_smbus, int, 0644);
1918 MODULE_PARM_DESC(elantech_smbus, "Use a secondary bus for the Elantech device.");
1919 
1920 static const char * const i2c_blacklist_pnp_ids[] = {
1921 	/*
1922 	 * These are known to not be working properly as bits are missing
1923 	 * in elan_i2c.
1924 	 */
1925 	NULL
1926 };
1927 
1928 static int elantech_create_smbus(struct psmouse *psmouse,
1929 				 struct elantech_device_info *info,
1930 				 bool leave_breadcrumbs)
1931 {
1932 	struct property_entry i2c_props[11] = {};
1933 	struct i2c_board_info smbus_board = {
1934 		I2C_BOARD_INFO("elan_i2c", 0x15),
1935 		.flags = I2C_CLIENT_HOST_NOTIFY,
1936 	};
1937 	unsigned int idx = 0;
1938 
1939 	i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-size-x",
1940 						   info->x_max + 1);
1941 	i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-size-y",
1942 						   info->y_max + 1);
1943 	i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-min-x",
1944 						   info->x_min);
1945 	i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-min-y",
1946 						   info->y_min);
1947 	if (info->x_res)
1948 		i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-x-mm",
1949 						      (info->x_max + 1) / info->x_res);
1950 	if (info->y_res)
1951 		i2c_props[idx++] = PROPERTY_ENTRY_U32("touchscreen-y-mm",
1952 						      (info->y_max + 1) / info->y_res);
1953 
1954 	if (info->has_trackpoint)
1955 		i2c_props[idx++] = PROPERTY_ENTRY_BOOL("elan,trackpoint");
1956 
1957 	if (info->has_middle_button)
1958 		i2c_props[idx++] = PROPERTY_ENTRY_BOOL("elan,middle-button");
1959 
1960 	if (info->x_traces)
1961 		i2c_props[idx++] = PROPERTY_ENTRY_U32("elan,x_traces",
1962 						      info->x_traces);
1963 	if (info->y_traces)
1964 		i2c_props[idx++] = PROPERTY_ENTRY_U32("elan,y_traces",
1965 						      info->y_traces);
1966 
1967 	if (elantech_is_buttonpad(info))
1968 		i2c_props[idx++] = PROPERTY_ENTRY_BOOL("elan,clickpad");
1969 
1970 	smbus_board.fwnode = fwnode_create_software_node(i2c_props, NULL);
1971 	if (IS_ERR(smbus_board.fwnode))
1972 		return PTR_ERR(smbus_board.fwnode);
1973 
1974 	return psmouse_smbus_init(psmouse, &smbus_board, NULL, 0, false,
1975 				  leave_breadcrumbs);
1976 }
1977 
1978 /*
1979  * elantech_setup_smbus - called once the PS/2 devices are enumerated
1980  * and decides to instantiate a SMBus InterTouch device.
1981  */
1982 static int elantech_setup_smbus(struct psmouse *psmouse,
1983 				struct elantech_device_info *info,
1984 				bool leave_breadcrumbs)
1985 {
1986 	int error;
1987 
1988 	if (elantech_smbus == ELANTECH_SMBUS_OFF)
1989 		return -ENXIO;
1990 
1991 	if (elantech_smbus == ELANTECH_SMBUS_NOT_SET) {
1992 		/*
1993 		 * New ICs are enabled by default, unless mentioned in
1994 		 * i2c_blacklist_pnp_ids.
1995 		 * Old ICs are up to the user to decide.
1996 		 */
1997 		if (!ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version) ||
1998 		    psmouse_matches_pnp_id(psmouse, i2c_blacklist_pnp_ids))
1999 			return -ENXIO;
2000 	}
2001 
2002 	psmouse_info(psmouse, "Trying to set up SMBus access\n");
2003 
2004 	error = elantech_create_smbus(psmouse, info, leave_breadcrumbs);
2005 	if (error) {
2006 		if (error == -EAGAIN)
2007 			psmouse_info(psmouse, "SMbus companion is not ready yet\n");
2008 		else
2009 			psmouse_err(psmouse, "unable to create intertouch device\n");
2010 
2011 		return error;
2012 	}
2013 
2014 	return 0;
2015 }
2016 
2017 static bool elantech_use_host_notify(struct psmouse *psmouse,
2018 				     struct elantech_device_info *info)
2019 {
2020 	if (ETP_NEW_IC_SMBUS_HOST_NOTIFY(info->fw_version))
2021 		return true;
2022 
2023 	switch (info->bus) {
2024 	case ETP_BUS_PS2_ONLY:
2025 		/* expected case */
2026 		break;
2027 	case ETP_BUS_SMB_ALERT_ONLY:
2028 	case ETP_BUS_PS2_SMB_ALERT:
2029 		psmouse_dbg(psmouse, "Ignoring SMBus provider through alert protocol.\n");
2030 		break;
2031 	case ETP_BUS_SMB_HST_NTFY_ONLY:
2032 	case ETP_BUS_PS2_SMB_HST_NTFY:
2033 		return true;
2034 	default:
2035 		psmouse_dbg(psmouse,
2036 			    "Ignoring SMBus bus provider %d.\n",
2037 			    info->bus);
2038 	}
2039 
2040 	return false;
2041 }
2042 
2043 int elantech_init_smbus(struct psmouse *psmouse)
2044 {
2045 	struct elantech_device_info info;
2046 	int error;
2047 
2048 	psmouse_reset(psmouse);
2049 
2050 	error = elantech_query_info(psmouse, &info);
2051 	if (error)
2052 		goto init_fail;
2053 
2054 	if (info.hw_version < 4) {
2055 		error = -ENXIO;
2056 		goto init_fail;
2057 	}
2058 
2059 	return elantech_create_smbus(psmouse, &info, false);
2060  init_fail:
2061 	psmouse_reset(psmouse);
2062 	return error;
2063 }
2064 #endif /* CONFIG_MOUSE_PS2_ELANTECH_SMBUS */
2065 
2066 /*
2067  * Initialize the touchpad and create sysfs entries
2068  */
2069 static int elantech_setup_ps2(struct psmouse *psmouse,
2070 			      struct elantech_device_info *info)
2071 {
2072 	struct elantech_data *etd;
2073 	int i;
2074 	int error = -EINVAL;
2075 	struct input_dev *tp_dev;
2076 
2077 	psmouse->private = etd = kzalloc(sizeof(*etd), GFP_KERNEL);
2078 	if (!etd)
2079 		return -ENOMEM;
2080 
2081 	etd->info = *info;
2082 
2083 	etd->parity[0] = 1;
2084 	for (i = 1; i < 256; i++)
2085 		etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
2086 
2087 	if (elantech_set_absolute_mode(psmouse)) {
2088 		psmouse_err(psmouse,
2089 			    "failed to put touchpad into absolute mode.\n");
2090 		goto init_fail;
2091 	}
2092 
2093 	if (info->fw_version == 0x381f17) {
2094 		etd->original_set_rate = psmouse->set_rate;
2095 		psmouse->set_rate = elantech_set_rate_restore_reg_07;
2096 	}
2097 
2098 	if (elantech_set_input_params(psmouse)) {
2099 		psmouse_err(psmouse, "failed to query touchpad range.\n");
2100 		goto init_fail;
2101 	}
2102 
2103 	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
2104 				   &elantech_attr_group);
2105 	if (error) {
2106 		psmouse_err(psmouse,
2107 			    "failed to create sysfs attributes, error: %d.\n",
2108 			    error);
2109 		goto init_fail;
2110 	}
2111 
2112 	if (info->has_trackpoint) {
2113 		tp_dev = input_allocate_device();
2114 
2115 		if (!tp_dev) {
2116 			error = -ENOMEM;
2117 			goto init_fail_tp_alloc;
2118 		}
2119 
2120 		etd->tp_dev = tp_dev;
2121 		snprintf(etd->tp_phys, sizeof(etd->tp_phys), "%s/input1",
2122 			psmouse->ps2dev.serio->phys);
2123 		tp_dev->phys = etd->tp_phys;
2124 		tp_dev->name = "ETPS/2 Elantech TrackPoint";
2125 		tp_dev->id.bustype = BUS_I8042;
2126 		tp_dev->id.vendor  = 0x0002;
2127 		tp_dev->id.product = PSMOUSE_ELANTECH;
2128 		tp_dev->id.version = 0x0000;
2129 		tp_dev->dev.parent = &psmouse->ps2dev.serio->dev;
2130 		tp_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
2131 		tp_dev->relbit[BIT_WORD(REL_X)] =
2132 			BIT_MASK(REL_X) | BIT_MASK(REL_Y);
2133 		tp_dev->keybit[BIT_WORD(BTN_LEFT)] =
2134 			BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_MIDDLE) |
2135 			BIT_MASK(BTN_RIGHT);
2136 
2137 		__set_bit(INPUT_PROP_POINTER, tp_dev->propbit);
2138 		__set_bit(INPUT_PROP_POINTING_STICK, tp_dev->propbit);
2139 
2140 		error = input_register_device(etd->tp_dev);
2141 		if (error < 0)
2142 			goto init_fail_tp_reg;
2143 	}
2144 
2145 	psmouse->protocol_handler = elantech_process_byte;
2146 	psmouse->disconnect = elantech_disconnect;
2147 	psmouse->reconnect = elantech_reconnect;
2148 	psmouse->fast_reconnect = NULL;
2149 	psmouse->pktsize = info->hw_version > 1 ? 6 : 4;
2150 
2151 	return 0;
2152  init_fail_tp_reg:
2153 	input_free_device(tp_dev);
2154  init_fail_tp_alloc:
2155 	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
2156 			   &elantech_attr_group);
2157  init_fail:
2158 	kfree(etd);
2159 	return error;
2160 }
2161 
2162 int elantech_init_ps2(struct psmouse *psmouse)
2163 {
2164 	struct elantech_device_info info;
2165 	int error;
2166 
2167 	psmouse_reset(psmouse);
2168 
2169 	error = elantech_query_info(psmouse, &info);
2170 	if (error)
2171 		goto init_fail;
2172 
2173 	error = elantech_setup_ps2(psmouse, &info);
2174 	if (error)
2175 		goto init_fail;
2176 
2177 	return 0;
2178  init_fail:
2179 	psmouse_reset(psmouse);
2180 	return error;
2181 }
2182 
2183 int elantech_init(struct psmouse *psmouse)
2184 {
2185 	struct elantech_device_info info;
2186 	int error;
2187 
2188 	psmouse_reset(psmouse);
2189 
2190 	error = elantech_query_info(psmouse, &info);
2191 	if (error)
2192 		goto init_fail;
2193 
2194 #if defined(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)
2195 
2196 	if (elantech_use_host_notify(psmouse, &info)) {
2197 		if (!IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) ||
2198 		    !IS_ENABLED(CONFIG_MOUSE_PS2_ELANTECH_SMBUS)) {
2199 			psmouse_warn(psmouse,
2200 				     "The touchpad can support a better bus than the too old PS/2 protocol. "
2201 				     "Make sure MOUSE_PS2_ELANTECH_SMBUS and MOUSE_ELAN_I2C_SMBUS are enabled to get a better touchpad experience.\n");
2202 		}
2203 		error = elantech_setup_smbus(psmouse, &info, true);
2204 		if (!error)
2205 			return PSMOUSE_ELANTECH_SMBUS;
2206 	}
2207 
2208 #endif /* CONFIG_MOUSE_PS2_ELANTECH_SMBUS */
2209 
2210 	error = elantech_setup_ps2(psmouse, &info);
2211 	if (error < 0) {
2212 		/*
2213 		 * Not using any flavor of Elantech support, so clean up
2214 		 * SMbus breadcrumbs, if any.
2215 		 */
2216 		psmouse_smbus_cleanup(psmouse);
2217 		goto init_fail;
2218 	}
2219 
2220 	return PSMOUSE_ELANTECH;
2221  init_fail:
2222 	psmouse_reset(psmouse);
2223 	return error;
2224 }
2225