drivers/input/mouse/elantech.c

   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/module.h>
  15 #include <linux/input.h>
  16 #include <linux/serio.h>
  17 #include <linux/libps2.h>
  18 #include "psmouse.h"
  19 #include "elantech.h"
  20
  21 #define elantech_debug(format, arg...)                          \
  22         do {                                                    \
  23                 if (etd->debug)                                 \
  24                         printk(KERN_DEBUG format, ##arg);       \
  25         } while (0)
  26
  27 /*
  28  * Send a Synaptics style sliced query command
  29  */
  30 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
  31                                 unsigned char *param)
  32 {
  33         if (psmouse_sliced_command(psmouse, c) ||
  34             ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
  35                 pr_err("elantech.c: synaptics_send_cmd query 0x%02x failed.\n", c);
  36                 return -1;
  37         }
  38
  39         return 0;
  40 }
  41
  42 /*
  43  * A retrying version of ps2_command
  44  */
  45 static int elantech_ps2_command(struct psmouse *psmouse,
  46                                 unsigned char *param, int command)
  47 {
  48         struct ps2dev *ps2dev = &psmouse->ps2dev;
  49         struct elantech_data *etd = psmouse->private;
  50         int rc;
  51         int tries = ETP_PS2_COMMAND_TRIES;
  52
  53         do {
  54                 rc = ps2_command(ps2dev, param, command);
  55                 if (rc == 0)
  56                         break;
  57                 tries--;
  58                 elantech_debug("elantech.c: retrying ps2 command 0x%02x (%d).\n",
  59                         command, tries);
  60                 msleep(ETP_PS2_COMMAND_DELAY);
  61         } while (tries > 0);
  62
  63         if (rc)
  64                 pr_err("elantech.c: ps2 command 0x%02x failed.\n", command);
  65
  66         return rc;
  67 }
  68
  69 /*
  70  * Send an Elantech style special command to read a value from a register
  71  */
  72 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
  73                                 unsigned char *val)
  74 {
  75         struct elantech_data *etd = psmouse->private;
  76         unsigned char param[3];
  77         int rc = 0;
  78
  79         if (reg < 0x10 || reg > 0x26)
  80                 return -1;
  81
  82         if (reg > 0x11 && reg < 0x20)
  83                 return -1;
  84
  85         switch (etd->hw_version) {
  86         case 1:
  87                 if (psmouse_sliced_command(psmouse, ETP_REGISTER_READ) ||
  88                     psmouse_sliced_command(psmouse, reg) ||
  89                     ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
  90                         rc = -1;
  91                 }
  92                 break;
  93
  94         case 2:
  95                 if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
  96                     elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
  97                     elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
  98                     elantech_ps2_command(psmouse,  NULL, reg) ||
  99                     elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
 100                         rc = -1;
 101                 }
 102                 break;
 103         }
 104
 105         if (rc)
 106                 pr_err("elantech.c: failed to read register 0x%02x.\n", reg);
 107         else
 108                 *val = param[0];
 109
 110         return rc;
 111 }
 112
 113 /*
 114  * Send an Elantech style special command to write a register with a value
 115  */
 116 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
 117                                 unsigned char val)
 118 {
 119         struct elantech_data *etd = psmouse->private;
 120         int rc = 0;
 121
 122         if (reg < 0x10 || reg > 0x26)
 123                 return -1;
 124
 125         if (reg > 0x11 && reg < 0x20)
 126                 return -1;
 127
 128         switch (etd->hw_version) {
 129         case 1:
 130                 if (psmouse_sliced_command(psmouse, ETP_REGISTER_WRITE) ||
 131                     psmouse_sliced_command(psmouse, reg) ||
 132                     psmouse_sliced_command(psmouse, val) ||
 133                     ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
 134                         rc = -1;
 135                 }
 136                 break;
 137
 138         case 2:
 139                 if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 140                     elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
 141                     elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 142                     elantech_ps2_command(psmouse, NULL, reg) ||
 143                     elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 144                     elantech_ps2_command(psmouse, NULL, val) ||
 145                     elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
 146                         rc = -1;
 147                 }
 148                 break;
 149         }
 150
 151         if (rc)
 152                 pr_err("elantech.c: failed to write register 0x%02x with value 0x%02x.\n",
 153                         reg, val);
 154
 155         return rc;
 156 }
 157
 158 /*
 159  * Dump a complete mouse movement packet to the syslog
 160  */
 161 static void elantech_packet_dump(unsigned char *packet, int size)
 162 {
 163         int     i;
 164
 165         printk(KERN_DEBUG "elantech.c: PS/2 packet [");
 166         for (i = 0; i < size; i++)
 167                 printk("%s0x%02x ", (i) ? ", " : " ", packet[i]);
 168         printk("]\n");
 169 }
 170
 171 /*
 172  * Interpret complete data packets and report absolute mode input events for
 173  * hardware version 1. (4 byte packets)
 174  */
 175 static void elantech_report_absolute_v1(struct psmouse *psmouse)
 176 {
 177         struct input_dev *dev = psmouse->dev;
 178         struct elantech_data *etd = psmouse->private;
 179         unsigned char *packet = psmouse->packet;
 180         int fingers;
 181         static int old_fingers;
 182
 183         if (etd->fw_version_maj == 0x01) {
 184                 /* byte 0:  D   U  p1  p2   1  p3   R   L
 185                    byte 1:  f   0  th  tw  x9  x8  y9  y8 */
 186                 fingers = ((packet[1] & 0x80) >> 7) +
 187                                 ((packet[1] & 0x30) >> 4);
 188         } else {
 189                 /* byte 0: n1  n0  p2  p1   1  p3   R   L
 190                    byte 1:  0   0   0   0  x9  x8  y9  y8 */
 191                 fingers = (packet[0] & 0xc0) >> 6;
 192         }
 193
 194         if (etd->jumpy_cursor) {
 195                 /* Discard packets that are likely to have bogus coordinates */
 196                 if (fingers > old_fingers) {
 197                         elantech_debug("elantech.c: discarding packet\n");
 198                         goto discard_packet_v1;
 199                 }
 200         }
 201
 202         input_report_key(dev, BTN_TOUCH, fingers != 0);
 203
 204         /* byte 2: x7  x6  x5  x4  x3  x2  x1  x0
 205            byte 3: y7  y6  y5  y4  y3  y2  y1  y0 */
 206         if (fingers) {
 207                 input_report_abs(dev, ABS_X,
 208                         ((packet[1] & 0x0c) << 6) | packet[2]);
 209                 input_report_abs(dev, ABS_Y, ETP_YMAX_V1 -
 210                         (((packet[1] & 0x03) << 8) | packet[3]));
 211         }
 212
 213         input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
 214         input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
 215         input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
 216         input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
 217         input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
 218
 219         if ((etd->fw_version_maj == 0x01) &&
 220             (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 221                 /* rocker up */
 222                 input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
 223                 /* rocker down */
 224                 input_report_key(dev, BTN_BACK, packet[0] & 0x80);
 225         }
 226
 227         input_sync(dev);
 228
 229  discard_packet_v1:
 230         old_fingers = fingers;
 231 }
 232
 233 /*
 234  * Interpret complete data packets and report absolute mode input events for
 235  * hardware version 2. (6 byte packets)
 236  */
 237 static void elantech_report_absolute_v2(struct psmouse *psmouse)
 238 {
 239         struct input_dev *dev = psmouse->dev;
 240         unsigned char *packet = psmouse->packet;
 241         int fingers, x1, y1, x2, y2;
 242
 243         /* byte 0: n1  n0   .   .   .   .   R   L */
 244         fingers = (packet[0] & 0xc0) >> 6;
 245         input_report_key(dev, BTN_TOUCH, fingers != 0);
 246
 247         switch (fingers) {
 248         case 1:
 249                 /* byte 1: x15 x14 x13 x12 x11 x10 x9  x8
 250                    byte 2: x7  x6  x5  x4  x4  x2  x1  x0 */
 251                 input_report_abs(dev, ABS_X, (packet[1] << 8) | packet[2]);
 252                 /* byte 4: y15 y14 y13 y12 y11 y10 y8  y8
 253                    byte 5: y7  y6  y5  y4  y3  y2  y1  y0 */
 254                 input_report_abs(dev, ABS_Y, ETP_YMAX_V2 -
 255                         ((packet[4] << 8) | packet[5]));
 256                 break;
 257
 258         case 2:
 259                 /* The coordinate of each finger is reported separately with
 260                    a lower resolution for two finger touches */
 261                 /* byte 0:  .   .  ay8 ax8  .   .   .   .
 262                    byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0 */
 263                 x1 = ((packet[0] & 0x10) << 4) | packet[1];
 264                 /* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
 265                 y1 = ETP_2FT_YMAX - (((packet[0] & 0x20) << 3) | packet[2]);
 266                 /* byte 3:  .   .  by8 bx8  .   .   .   .
 267                    byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0 */
 268                 x2 = ((packet[3] & 0x10) << 4) | packet[4];
 269                 /* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
 270                 y2 = ETP_2FT_YMAX - (((packet[3] & 0x20) << 3) | packet[5]);
 271                 /* For compatibility with the X Synaptics driver scale up one
 272                    coordinate and report as ordinary mouse movent */
 273                 input_report_abs(dev, ABS_X, x1 << 2);
 274                 input_report_abs(dev, ABS_Y, y1 << 2);
 275                 /* For compatibility with the proprietary X Elantech driver
 276                    report both coordinates as hat coordinates */
 277                 input_report_abs(dev, ABS_HAT0X, x1);
 278                 input_report_abs(dev, ABS_HAT0Y, y1);
 279                 input_report_abs(dev, ABS_HAT1X, x2);
 280                 input_report_abs(dev, ABS_HAT1Y, y2);
 281                 break;
 282         }
 283
 284         input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
 285         input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
 286         input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
 287         input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
 288         input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
 289
 290         input_sync(dev);
 291 }
 292
 293 static int elantech_check_parity_v1(struct psmouse *psmouse)
 294 {
 295         struct elantech_data *etd = psmouse->private;
 296         unsigned char *packet = psmouse->packet;
 297         unsigned char p1, p2, p3;
 298
 299         /* Parity bits are placed differently */
 300         if (etd->fw_version_maj == 0x01) {
 301                 /* byte 0:  D   U  p1  p2   1  p3   R   L */
 302                 p1 = (packet[0] & 0x20) >> 5;
 303                 p2 = (packet[0] & 0x10) >> 4;
 304         } else {
 305                 /* byte 0: n1  n0  p2  p1   1  p3   R   L */
 306                 p1 = (packet[0] & 0x10) >> 4;
 307                 p2 = (packet[0] & 0x20) >> 5;
 308         }
 309
 310         p3 = (packet[0] & 0x04) >> 2;
 311
 312         return etd->parity[packet[1]] == p1 &&
 313                etd->parity[packet[2]] == p2 &&
 314                etd->parity[packet[3]] == p3;
 315 }
 316
 317 /*
 318  * Process byte stream from mouse and handle complete packets
 319  */
 320 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
 321 {
 322         struct elantech_data *etd = psmouse->private;
 323
 324         if (psmouse->pktcnt < psmouse->pktsize)
 325                 return PSMOUSE_GOOD_DATA;
 326
 327         if (etd->debug > 1)
 328                 elantech_packet_dump(psmouse->packet, psmouse->pktsize);
 329
 330         switch (etd->hw_version) {
 331         case 1:
 332                 if (etd->paritycheck && !elantech_check_parity_v1(psmouse))
 333                         return PSMOUSE_BAD_DATA;
 334
 335                 elantech_report_absolute_v1(psmouse);
 336                 break;
 337
 338         case 2:
 339                 /* We don't know how to check parity in protocol v2 */
 340                 elantech_report_absolute_v2(psmouse);
 341                 break;
 342         }
 343
 344         return PSMOUSE_FULL_PACKET;
 345 }
 346
 347 /*
 348  * Put the touchpad into absolute mode
 349  */
 350 static int elantech_set_absolute_mode(struct psmouse *psmouse)
 351 {
 352         struct elantech_data *etd = psmouse->private;
 353         unsigned char val;
 354         int tries = ETP_READ_BACK_TRIES;
 355         int rc = 0;
 356
 357         switch (etd->hw_version) {
 358         case 1:
 359                 etd->reg_10 = 0x16;
 360                 etd->reg_11 = 0x8f;
 361                 if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
 362                     elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
 363                         rc = -1;
 364                 }
 365                 break;
 366
 367         case 2:
 368                                         /* Windows driver values */
 369                 etd->reg_10 = 0x54;
 370                 etd->reg_11 = 0x88;     /* 0x8a */
 371                 etd->reg_21 = 0x60;     /* 0x00 */
 372                 if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
 373                     elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
 374                     elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
 375                         rc = -1;
 376                         break;
 377                 }
 378         }
 379
 380         if (rc == 0) {
 381                 /*
 382                  * Read back reg 0x10. For hardware version 1 we must make
 383                  * sure the absolute mode bit is set. For hardware version 2
 384                  * the touchpad is probably initalising and not ready until
 385                  * we read back the value we just wrote.
 386                  */
 387                 do {
 388                         rc = elantech_read_reg(psmouse, 0x10, &val);
 389                         if (rc == 0)
 390                                 break;
 391                         tries--;
 392                         elantech_debug("elantech.c: retrying read (%d).\n",
 393                                         tries);
 394                         msleep(ETP_READ_BACK_DELAY);
 395                 } while (tries > 0);
 396
 397                 if (rc) {
 398                         pr_err("elantech.c: failed to read back register 0x10.\n");
 399                 } else if (etd->hw_version == 1 &&
 400                            !(val & ETP_R10_ABSOLUTE_MODE)) {
 401                         pr_err("elantech.c: touchpad refuses "
 402                                 "to switch to absolute mode.\n");
 403                         rc = -1;
 404                 }
 405         }
 406
 407         if (rc)
 408                 pr_err("elantech.c: failed to initialise registers.\n");
 409
 410         return rc;
 411 }
 412
 413 /*
 414  * Set the appropriate event bits for the input subsystem
 415  */
 416 static void elantech_set_input_params(struct psmouse *psmouse)
 417 {
 418         struct input_dev *dev = psmouse->dev;
 419         struct elantech_data *etd = psmouse->private;
 420
 421         __set_bit(EV_KEY, dev->evbit);
 422         __set_bit(EV_ABS, dev->evbit);
 423         __clear_bit(EV_REL, dev->evbit);
 424
 425         __set_bit(BTN_LEFT, dev->keybit);
 426         __set_bit(BTN_RIGHT, dev->keybit);
 427
 428         __set_bit(BTN_TOUCH, dev->keybit);
 429         __set_bit(BTN_TOOL_FINGER, dev->keybit);
 430         __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
 431         __set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
 432
 433         switch (etd->hw_version) {
 434         case 1:
 435                 /* Rocker button */
 436                 if ((etd->fw_version_maj == 0x01) &&
 437                     (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 438                         __set_bit(BTN_FORWARD, dev->keybit);
 439                         __set_bit(BTN_BACK, dev->keybit);
 440                 }
 441                 input_set_abs_params(dev, ABS_X, ETP_XMIN_V1, ETP_XMAX_V1, 0, 0);
 442                 input_set_abs_params(dev, ABS_Y, ETP_YMIN_V1, ETP_YMAX_V1, 0, 0);
 443                 break;
 444
 445         case 2:
 446                 input_set_abs_params(dev, ABS_X, ETP_XMIN_V2, ETP_XMAX_V2, 0, 0);
 447                 input_set_abs_params(dev, ABS_Y, ETP_YMIN_V2, ETP_YMAX_V2, 0, 0);
 448                 input_set_abs_params(dev, ABS_HAT0X, ETP_2FT_XMIN, ETP_2FT_XMAX, 0, 0);
 449                 input_set_abs_params(dev, ABS_HAT0Y, ETP_2FT_YMIN, ETP_2FT_YMAX, 0, 0);
 450                 input_set_abs_params(dev, ABS_HAT1X, ETP_2FT_XMIN, ETP_2FT_XMAX, 0, 0);
 451                 input_set_abs_params(dev, ABS_HAT1Y, ETP_2FT_YMIN, ETP_2FT_YMAX, 0, 0);
 452                 break;
 453         }
 454 }
 455
 456 struct elantech_attr_data {
 457         size_t          field_offset;
 458         unsigned char   reg;
 459 };
 460
 461 /*
 462  * Display a register value by reading a sysfs entry
 463  */
 464 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
 465                                         char *buf)
 466 {
 467         struct elantech_data *etd = psmouse->private;
 468         struct elantech_attr_data *attr = data;
 469         unsigned char *reg = (unsigned char *) etd + attr->field_offset;
 470         int rc = 0;
 471
 472         if (attr->reg)
 473                 rc = elantech_read_reg(psmouse, attr->reg, reg);
 474
 475         return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
 476 }
 477
 478 /*
 479  * Write a register value by writing a sysfs entry
 480  */
 481 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
 482                                      void *data, const char *buf, size_t count)
 483 {
 484         struct elantech_data *etd = psmouse->private;
 485         struct elantech_attr_data *attr = data;
 486         unsigned char *reg = (unsigned char *) etd + attr->field_offset;
 487         unsigned long value;
 488         int err;
 489
 490         err = strict_strtoul(buf, 16, &value);
 491         if (err)
 492                 return err;
 493
 494         if (value > 0xff)
 495                 return -EINVAL;
 496
 497         /* Do we need to preserve some bits for version 2 hardware too? */
 498         if (etd->hw_version == 1) {
 499                 if (attr->reg == 0x10)
 500                         /* Force absolute mode always on */
 501                         value |= ETP_R10_ABSOLUTE_MODE;
 502                 else if (attr->reg == 0x11)
 503                         /* Force 4 byte mode always on */
 504                         value |= ETP_R11_4_BYTE_MODE;
 505         }
 506
 507         if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
 508                 *reg = value;
 509
 510         return count;
 511 }
 512
 513 #define ELANTECH_INT_ATTR(_name, _register)                             \
 514         static struct elantech_attr_data elantech_attr_##_name = {      \
 515                 .field_offset = offsetof(struct elantech_data, _name),  \
 516                 .reg = _register,                                       \
 517         };                                                              \
 518         PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,                   \
 519                             &elantech_attr_##_name,                     \
 520                             elantech_show_int_attr,                     \
 521                             elantech_set_int_attr)
 522
 523 ELANTECH_INT_ATTR(reg_10, 0x10);
 524 ELANTECH_INT_ATTR(reg_11, 0x11);
 525 ELANTECH_INT_ATTR(reg_20, 0x20);
 526 ELANTECH_INT_ATTR(reg_21, 0x21);
 527 ELANTECH_INT_ATTR(reg_22, 0x22);
 528 ELANTECH_INT_ATTR(reg_23, 0x23);
 529 ELANTECH_INT_ATTR(reg_24, 0x24);
 530 ELANTECH_INT_ATTR(reg_25, 0x25);
 531 ELANTECH_INT_ATTR(reg_26, 0x26);
 532 ELANTECH_INT_ATTR(debug, 0);
 533 ELANTECH_INT_ATTR(paritycheck, 0);
 534
 535 static struct attribute *elantech_attrs[] = {
 536         &psmouse_attr_reg_10.dattr.attr,
 537         &psmouse_attr_reg_11.dattr.attr,
 538         &psmouse_attr_reg_20.dattr.attr,
 539         &psmouse_attr_reg_21.dattr.attr,
 540         &psmouse_attr_reg_22.dattr.attr,
 541         &psmouse_attr_reg_23.dattr.attr,
 542         &psmouse_attr_reg_24.dattr.attr,
 543         &psmouse_attr_reg_25.dattr.attr,
 544         &psmouse_attr_reg_26.dattr.attr,
 545         &psmouse_attr_debug.dattr.attr,
 546         &psmouse_attr_paritycheck.dattr.attr,
 547         NULL
 548 };
 549
 550 static struct attribute_group elantech_attr_group = {
 551         .attrs = elantech_attrs,
 552 };
 553
 554 /*
 555  * Use magic knock to detect Elantech touchpad
 556  */
 557 int elantech_detect(struct psmouse *psmouse, bool set_properties)
 558 {
 559         struct ps2dev *ps2dev = &psmouse->ps2dev;
 560         unsigned char param[3];
 561
 562         ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
 563
 564         if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
 565             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 566             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 567             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 568             ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
 569                 pr_debug("elantech.c: sending Elantech magic knock failed.\n");
 570                 return -1;
 571         }
 572
 573         /*
 574          * Report this in case there are Elantech models that use a different
 575          * set of magic numbers
 576          */
 577         if (param[0] != 0x3c || param[1] != 0x03 || param[2] != 0xc8) {
 578                 pr_debug("elantech.c: "
 579                          "unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
 580                          param[0], param[1], param[2]);
 581                 return -1;
 582         }
 583
 584         /*
 585          * Query touchpad's firmware version and see if it reports known
 586          * value to avoid mis-detection. Logitech mice are known to respond
 587          * to Elantech magic knock and there might be more.
 588          */
 589         if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
 590                 pr_debug("elantech.c: failed to query firmware version.\n");
 591                 return -1;
 592         }
 593
 594         pr_debug("elantech.c: Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
 595                  param[0], param[1], param[2]);
 596
 597         if (param[0] == 0 || param[1] != 0) {
 598                 pr_debug("elantech.c: Probably not a real Elantech touchpad. Aborting.\n");
 599                 return -1;
 600         }
 601
 602         if (set_properties) {
 603                 psmouse->vendor = "Elantech";
 604                 psmouse->name = "Touchpad";
 605         }
 606
 607         return 0;
 608 }
 609
 610 /*
 611  * Clean up sysfs entries when disconnecting
 612  */
 613 static void elantech_disconnect(struct psmouse *psmouse)
 614 {
 615         sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
 616                            &elantech_attr_group);
 617         kfree(psmouse->private);
 618         psmouse->private = NULL;
 619 }
 620
 621 /*
 622  * Put the touchpad back into absolute mode when reconnecting
 623  */
 624 static int elantech_reconnect(struct psmouse *psmouse)
 625 {
 626         if (elantech_detect(psmouse, 0))
 627                 return -1;
 628
 629         if (elantech_set_absolute_mode(psmouse)) {
 630                 pr_err("elantech.c: failed to put touchpad back into absolute mode.\n");
 631                 return -1;
 632         }
 633
 634         return 0;
 635 }
 636
 637 /*
 638  * Initialize the touchpad and create sysfs entries
 639  */
 640 int elantech_init(struct psmouse *psmouse)
 641 {
 642         struct elantech_data *etd;
 643         int i, error;
 644         unsigned char param[3];
 645
 646         psmouse->private = etd = kzalloc(sizeof(struct elantech_data), GFP_KERNEL);
 647         if (!etd)
 648                 return -1;
 649
 650         etd->parity[0] = 1;
 651         for (i = 1; i < 256; i++)
 652                 etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
 653
 654         /*
 655          * Do the version query again so we can store the result
 656          */
 657         if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
 658                 pr_err("elantech.c: failed to query firmware version.\n");
 659                 goto init_fail;
 660         }
 661         etd->fw_version_maj = param[0];
 662         etd->fw_version_min = param[2];
 663
 664         /*
 665          * Assume every version greater than this is new EeePC style
 666          * hardware with 6 byte packets
 667          */
 668         if (etd->fw_version_maj >= 0x02 && etd->fw_version_min >= 0x30) {
 669                 etd->hw_version = 2;
 670                 /* For now show extra debug information */
 671                 etd->debug = 1;
 672                 /* Don't know how to do parity checking for version 2 */
 673                 etd->paritycheck = 0;
 674         } else {
 675                 etd->hw_version = 1;
 676                 etd->paritycheck = 1;
 677         }
 678         pr_info("elantech.c: assuming hardware version %d, firmware version %d.%d\n",
 679                 etd->hw_version, etd->fw_version_maj, etd->fw_version_min);
 680
 681         if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY, param)) {
 682                 pr_err("elantech.c: failed to query capabilities.\n");
 683                 goto init_fail;
 684         }
 685         pr_info("elantech.c: Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
 686                 param[0], param[1], param[2]);
 687         etd->capabilities = param[0];
 688
 689         /*
 690          * This firmware seems to suffer from misreporting coordinates when
 691          * a touch action starts causing the mouse cursor or scrolled page
 692          * to jump. Enable a workaround.
 693          */
 694         if (etd->fw_version_maj == 0x02 && etd->fw_version_min == 0x22) {
 695                 pr_info("elantech.c: firmware version 2.34 detected, "
 696                         "enabling jumpy cursor workaround\n");
 697                 etd->jumpy_cursor = 1;
 698         }
 699
 700         if (elantech_set_absolute_mode(psmouse)) {
 701                 pr_err("elantech.c: failed to put touchpad into absolute mode.\n");
 702                 goto init_fail;
 703         }
 704
 705         elantech_set_input_params(psmouse);
 706
 707         error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
 708                                    &elantech_attr_group);
 709         if (error) {
 710                 pr_err("elantech.c: failed to create sysfs attributes, error: %d.\n",
 711                         error);
 712                 goto init_fail;
 713         }
 714
 715         psmouse->protocol_handler = elantech_process_byte;
 716         psmouse->disconnect = elantech_disconnect;
 717         psmouse->reconnect = elantech_reconnect;
 718         psmouse->pktsize = etd->hw_version == 2 ? 6 : 4;
 719
 720         return 0;
 721
 722  init_fail:
 723         kfree(etd);
 724         return -1;
 725 }