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 #define pr_fmt(fmt) KBUILD_BASENAME ": " fmt
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/input.h>
  19 #include <linux/serio.h>
  20 #include <linux/libps2.h>
  21 #include "psmouse.h"
  22 #include "elantech.h"
  23
  24 #define elantech_debug(fmt, ...)                                        \
  25         do {                                                            \
  26                 if (etd->debug)                                         \
  27                         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__);  \
  28         } while (0)
  29
  30 static bool force_elantech;
  31 module_param_named(force_elantech, force_elantech, bool, 0644);
  32 MODULE_PARM_DESC(force_elantech, "Force the Elantech PS/2 protocol extension to be used, 1 = enabled, 0 = disabled (default).");
  33
  34 /*
  35  * Send a Synaptics style sliced query command
  36  */
  37 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
  38                                 unsigned char *param)
  39 {
  40         if (psmouse_sliced_command(psmouse, c) ||
  41             ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
  42                 pr_err("synaptics_send_cmd query 0x%02x failed.\n", c);
  43                 return -1;
  44         }
  45
  46         return 0;
  47 }
  48
  49 /*
  50  * A retrying version of ps2_command
  51  */
  52 static int elantech_ps2_command(struct psmouse *psmouse,
  53                                 unsigned char *param, int command)
  54 {
  55         struct ps2dev *ps2dev = &psmouse->ps2dev;
  56         struct elantech_data *etd = psmouse->private;
  57         int rc;
  58         int tries = ETP_PS2_COMMAND_TRIES;
  59
  60         do {
  61                 rc = ps2_command(ps2dev, param, command);
  62                 if (rc == 0)
  63                         break;
  64                 tries--;
  65                 elantech_debug("retrying ps2 command 0x%02x (%d).\n",
  66                                 command, tries);
  67                 msleep(ETP_PS2_COMMAND_DELAY);
  68         } while (tries > 0);
  69
  70         if (rc)
  71                 pr_err("ps2 command 0x%02x failed.\n", command);
  72
  73         return rc;
  74 }
  75
  76 /*
  77  * Send an Elantech style special command to read a value from a register
  78  */
  79 static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
  80                                 unsigned char *val)
  81 {
  82         struct elantech_data *etd = psmouse->private;
  83         unsigned char param[3];
  84         int rc = 0;
  85
  86         if (reg < 0x10 || reg > 0x26)
  87                 return -1;
  88
  89         if (reg > 0x11 && reg < 0x20)
  90                 return -1;
  91
  92         switch (etd->hw_version) {
  93         case 1:
  94                 if (psmouse_sliced_command(psmouse, ETP_REGISTER_READ) ||
  95                     psmouse_sliced_command(psmouse, reg) ||
  96                     ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
  97                         rc = -1;
  98                 }
  99                 break;
 100
 101         case 2:
 102                 if (elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
 103                     elantech_ps2_command(psmouse,  NULL, ETP_REGISTER_READ) ||
 104                     elantech_ps2_command(psmouse,  NULL, ETP_PS2_CUSTOM_COMMAND) ||
 105                     elantech_ps2_command(psmouse,  NULL, reg) ||
 106                     elantech_ps2_command(psmouse, param, PSMOUSE_CMD_GETINFO)) {
 107                         rc = -1;
 108                 }
 109                 break;
 110         }
 111
 112         if (rc)
 113                 pr_err("failed to read register 0x%02x.\n", reg);
 114         else
 115                 *val = param[0];
 116
 117         return rc;
 118 }
 119
 120 /*
 121  * Send an Elantech style special command to write a register with a value
 122  */
 123 static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
 124                                 unsigned char val)
 125 {
 126         struct elantech_data *etd = psmouse->private;
 127         int rc = 0;
 128
 129         if (reg < 0x10 || reg > 0x26)
 130                 return -1;
 131
 132         if (reg > 0x11 && reg < 0x20)
 133                 return -1;
 134
 135         switch (etd->hw_version) {
 136         case 1:
 137                 if (psmouse_sliced_command(psmouse, ETP_REGISTER_WRITE) ||
 138                     psmouse_sliced_command(psmouse, reg) ||
 139                     psmouse_sliced_command(psmouse, val) ||
 140                     ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
 141                         rc = -1;
 142                 }
 143                 break;
 144
 145         case 2:
 146                 if (elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 147                     elantech_ps2_command(psmouse, NULL, ETP_REGISTER_WRITE) ||
 148                     elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 149                     elantech_ps2_command(psmouse, NULL, reg) ||
 150                     elantech_ps2_command(psmouse, NULL, ETP_PS2_CUSTOM_COMMAND) ||
 151                     elantech_ps2_command(psmouse, NULL, val) ||
 152                     elantech_ps2_command(psmouse, NULL, PSMOUSE_CMD_SETSCALE11)) {
 153                         rc = -1;
 154                 }
 155                 break;
 156         }
 157
 158         if (rc)
 159                 pr_err("failed to write register 0x%02x with value 0x%02x.\n",
 160                         reg, val);
 161
 162         return rc;
 163 }
 164
 165 /*
 166  * Dump a complete mouse movement packet to the syslog
 167  */
 168 static void elantech_packet_dump(unsigned char *packet, int size)
 169 {
 170         int     i;
 171
 172         printk(KERN_DEBUG pr_fmt("PS/2 packet ["));
 173         for (i = 0; i < size; i++)
 174                 printk("%s0x%02x ", (i) ? ", " : " ", packet[i]);
 175         printk("]\n");
 176 }
 177
 178 /*
 179  * Interpret complete data packets and report absolute mode input events for
 180  * hardware version 1. (4 byte packets)
 181  */
 182 static void elantech_report_absolute_v1(struct psmouse *psmouse)
 183 {
 184         struct input_dev *dev = psmouse->dev;
 185         struct elantech_data *etd = psmouse->private;
 186         unsigned char *packet = psmouse->packet;
 187         int fingers;
 188         static int old_fingers;
 189
 190         if (etd->fw_version < 0x020000) {
 191                 /*
 192                  * byte 0:  D   U  p1  p2   1  p3   R   L
 193                  * byte 1:  f   0  th  tw  x9  x8  y9  y8
 194                  */
 195                 fingers = ((packet[1] & 0x80) >> 7) +
 196                                 ((packet[1] & 0x30) >> 4);
 197         } else {
 198                 /*
 199                  * byte 0: n1  n0  p2  p1   1  p3   R   L
 200                  * byte 1:  0   0   0   0  x9  x8  y9  y8
 201                  */
 202                 fingers = (packet[0] & 0xc0) >> 6;
 203         }
 204
 205         if (etd->jumpy_cursor) {
 206                 /* Discard packets that are likely to have bogus coordinates */
 207                 if (fingers > old_fingers) {
 208                         elantech_debug("discarding packet\n");
 209                         goto discard_packet_v1;
 210                 }
 211         }
 212
 213         input_report_key(dev, BTN_TOUCH, fingers != 0);
 214
 215         /*
 216          * byte 2: x7  x6  x5  x4  x3  x2  x1  x0
 217          * byte 3: y7  y6  y5  y4  y3  y2  y1  y0
 218          */
 219         if (fingers) {
 220                 input_report_abs(dev, ABS_X,
 221                         ((packet[1] & 0x0c) << 6) | packet[2]);
 222                 input_report_abs(dev, ABS_Y,
 223                         ETP_YMAX_V1 - (((packet[1] & 0x03) << 8) | packet[3]));
 224         }
 225
 226         input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
 227         input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
 228         input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
 229         input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
 230         input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
 231
 232         if (etd->fw_version < 0x020000 &&
 233             (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 234                 /* rocker up */
 235                 input_report_key(dev, BTN_FORWARD, packet[0] & 0x40);
 236                 /* rocker down */
 237                 input_report_key(dev, BTN_BACK, packet[0] & 0x80);
 238         }
 239
 240         input_sync(dev);
 241
 242  discard_packet_v1:
 243         old_fingers = fingers;
 244 }
 245
 246 /*
 247  * Interpret complete data packets and report absolute mode input events for
 248  * hardware version 2. (6 byte packets)
 249  */
 250 static void elantech_report_absolute_v2(struct psmouse *psmouse)
 251 {
 252         struct input_dev *dev = psmouse->dev;
 253         unsigned char *packet = psmouse->packet;
 254         int fingers, x1, y1, x2, y2;
 255
 256         /* byte 0: n1  n0   .   .   .   .   R   L */
 257         fingers = (packet[0] & 0xc0) >> 6;
 258         input_report_key(dev, BTN_TOUCH, fingers != 0);
 259
 260         switch (fingers) {
 261         case 1:
 262                 /*
 263                  * byte 1:  .   .   .   .   .  x10 x9  x8
 264                  * byte 2: x7  x6  x5  x4  x4  x2  x1  x0
 265                  */
 266                 input_report_abs(dev, ABS_X,
 267                         ((packet[1] & 0x07) << 8) | packet[2]);
 268                 /*
 269                  * byte 4:  .   .   .   .   .   .  y9  y8
 270                  * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
 271                  */
 272                 input_report_abs(dev, ABS_Y,
 273                         ETP_YMAX_V2 - (((packet[4] & 0x03) << 8) | packet[5]));
 274                 break;
 275
 276         case 2:
 277                 /*
 278                  * The coordinate of each finger is reported separately
 279                  * with a lower resolution for two finger touches:
 280                  * byte 0:  .   .  ay8 ax8  .   .   .   .
 281                  * byte 1: ax7 ax6 ax5 ax4 ax3 ax2 ax1 ax0
 282                  */
 283                 x1 = ((packet[0] & 0x10) << 4) | packet[1];
 284                 /* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
 285                 y1 = ETP_2FT_YMAX - (((packet[0] & 0x20) << 3) | packet[2]);
 286                 /*
 287                  * byte 3:  .   .  by8 bx8  .   .   .   .
 288                  * byte 4: bx7 bx6 bx5 bx4 bx3 bx2 bx1 bx0
 289                  */
 290                 x2 = ((packet[3] & 0x10) << 4) | packet[4];
 291                 /* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
 292                 y2 = ETP_2FT_YMAX - (((packet[3] & 0x20) << 3) | packet[5]);
 293                 /*
 294                  * For compatibility with the X Synaptics driver scale up
 295                  * one coordinate and report as ordinary mouse movent
 296                  */
 297                 input_report_abs(dev, ABS_X, x1 << 2);
 298                 input_report_abs(dev, ABS_Y, y1 << 2);
 299                 /*
 300                  * For compatibility with the proprietary X Elantech driver
 301                  * report both coordinates as hat coordinates
 302                  */
 303                 input_report_abs(dev, ABS_HAT0X, x1);
 304                 input_report_abs(dev, ABS_HAT0Y, y1);
 305                 input_report_abs(dev, ABS_HAT1X, x2);
 306                 input_report_abs(dev, ABS_HAT1Y, y2);
 307                 break;
 308         }
 309
 310         input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
 311         input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
 312         input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
 313         input_report_key(dev, BTN_LEFT, packet[0] & 0x01);
 314         input_report_key(dev, BTN_RIGHT, packet[0] & 0x02);
 315
 316         input_sync(dev);
 317 }
 318
 319 static int elantech_check_parity_v1(struct psmouse *psmouse)
 320 {
 321         struct elantech_data *etd = psmouse->private;
 322         unsigned char *packet = psmouse->packet;
 323         unsigned char p1, p2, p3;
 324
 325         /* Parity bits are placed differently */
 326         if (etd->fw_version < 0x020000) {
 327                 /* byte 0:  D   U  p1  p2   1  p3   R   L */
 328                 p1 = (packet[0] & 0x20) >> 5;
 329                 p2 = (packet[0] & 0x10) >> 4;
 330         } else {
 331                 /* byte 0: n1  n0  p2  p1   1  p3   R   L */
 332                 p1 = (packet[0] & 0x10) >> 4;
 333                 p2 = (packet[0] & 0x20) >> 5;
 334         }
 335
 336         p3 = (packet[0] & 0x04) >> 2;
 337
 338         return etd->parity[packet[1]] == p1 &&
 339                etd->parity[packet[2]] == p2 &&
 340                etd->parity[packet[3]] == p3;
 341 }
 342
 343 /*
 344  * Process byte stream from mouse and handle complete packets
 345  */
 346 static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse)
 347 {
 348         struct elantech_data *etd = psmouse->private;
 349
 350         if (psmouse->pktcnt < psmouse->pktsize)
 351                 return PSMOUSE_GOOD_DATA;
 352
 353         if (etd->debug > 1)
 354                 elantech_packet_dump(psmouse->packet, psmouse->pktsize);
 355
 356         switch (etd->hw_version) {
 357         case 1:
 358                 if (etd->paritycheck && !elantech_check_parity_v1(psmouse))
 359                         return PSMOUSE_BAD_DATA;
 360
 361                 elantech_report_absolute_v1(psmouse);
 362                 break;
 363
 364         case 2:
 365                 /* We don't know how to check parity in protocol v2 */
 366                 elantech_report_absolute_v2(psmouse);
 367                 break;
 368         }
 369
 370         return PSMOUSE_FULL_PACKET;
 371 }
 372
 373 /*
 374  * Put the touchpad into absolute mode
 375  */
 376 static int elantech_set_absolute_mode(struct psmouse *psmouse)
 377 {
 378         struct elantech_data *etd = psmouse->private;
 379         unsigned char val;
 380         int tries = ETP_READ_BACK_TRIES;
 381         int rc = 0;
 382
 383         switch (etd->hw_version) {
 384         case 1:
 385                 etd->reg_10 = 0x16;
 386                 etd->reg_11 = 0x8f;
 387                 if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
 388                     elantech_write_reg(psmouse, 0x11, etd->reg_11)) {
 389                         rc = -1;
 390                 }
 391                 break;
 392
 393         case 2:
 394                                         /* Windows driver values */
 395                 etd->reg_10 = 0x54;
 396                 etd->reg_11 = 0x88;     /* 0x8a */
 397                 etd->reg_21 = 0x60;     /* 0x00 */
 398                 if (elantech_write_reg(psmouse, 0x10, etd->reg_10) ||
 399                     elantech_write_reg(psmouse, 0x11, etd->reg_11) ||
 400                     elantech_write_reg(psmouse, 0x21, etd->reg_21)) {
 401                         rc = -1;
 402                         break;
 403                 }
 404         }
 405
 406         if (rc == 0) {
 407                 /*
 408                  * Read back reg 0x10. For hardware version 1 we must make
 409                  * sure the absolute mode bit is set. For hardware version 2
 410                  * the touchpad is probably initalising and not ready until
 411                  * we read back the value we just wrote.
 412                  */
 413                 do {
 414                         rc = elantech_read_reg(psmouse, 0x10, &val);
 415                         if (rc == 0)
 416                                 break;
 417                         tries--;
 418                         elantech_debug("retrying read (%d).\n", tries);
 419                         msleep(ETP_READ_BACK_DELAY);
 420                 } while (tries > 0);
 421
 422                 if (rc) {
 423                         pr_err("failed to read back register 0x10.\n");
 424                 } else if (etd->hw_version == 1 &&
 425                            !(val & ETP_R10_ABSOLUTE_MODE)) {
 426                         pr_err("touchpad refuses to switch to absolute mode.\n");
 427                         rc = -1;
 428                 }
 429         }
 430
 431         if (rc)
 432                 pr_err("failed to initialise registers.\n");
 433
 434         return rc;
 435 }
 436
 437 /*
 438  * Set the appropriate event bits for the input subsystem
 439  */
 440 static void elantech_set_input_params(struct psmouse *psmouse)
 441 {
 442         struct input_dev *dev = psmouse->dev;
 443         struct elantech_data *etd = psmouse->private;
 444
 445         __set_bit(EV_KEY, dev->evbit);
 446         __set_bit(EV_ABS, dev->evbit);
 447         __clear_bit(EV_REL, dev->evbit);
 448
 449         __set_bit(BTN_LEFT, dev->keybit);
 450         __set_bit(BTN_RIGHT, dev->keybit);
 451
 452         __set_bit(BTN_TOUCH, dev->keybit);
 453         __set_bit(BTN_TOOL_FINGER, dev->keybit);
 454         __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
 455         __set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
 456
 457         switch (etd->hw_version) {
 458         case 1:
 459                 /* Rocker button */
 460                 if (etd->fw_version < 0x020000 &&
 461                     (etd->capabilities & ETP_CAP_HAS_ROCKER)) {
 462                         __set_bit(BTN_FORWARD, dev->keybit);
 463                         __set_bit(BTN_BACK, dev->keybit);
 464                 }
 465                 input_set_abs_params(dev, ABS_X, ETP_XMIN_V1, ETP_XMAX_V1, 0, 0);
 466                 input_set_abs_params(dev, ABS_Y, ETP_YMIN_V1, ETP_YMAX_V1, 0, 0);
 467                 break;
 468
 469         case 2:
 470                 input_set_abs_params(dev, ABS_X, ETP_XMIN_V2, ETP_XMAX_V2, 0, 0);
 471                 input_set_abs_params(dev, ABS_Y, ETP_YMIN_V2, ETP_YMAX_V2, 0, 0);
 472                 input_set_abs_params(dev, ABS_HAT0X, ETP_2FT_XMIN, ETP_2FT_XMAX, 0, 0);
 473                 input_set_abs_params(dev, ABS_HAT0Y, ETP_2FT_YMIN, ETP_2FT_YMAX, 0, 0);
 474                 input_set_abs_params(dev, ABS_HAT1X, ETP_2FT_XMIN, ETP_2FT_XMAX, 0, 0);
 475                 input_set_abs_params(dev, ABS_HAT1Y, ETP_2FT_YMIN, ETP_2FT_YMAX, 0, 0);
 476                 break;
 477         }
 478 }
 479
 480 struct elantech_attr_data {
 481         size_t          field_offset;
 482         unsigned char   reg;
 483 };
 484
 485 /*
 486  * Display a register value by reading a sysfs entry
 487  */
 488 static ssize_t elantech_show_int_attr(struct psmouse *psmouse, void *data,
 489                                         char *buf)
 490 {
 491         struct elantech_data *etd = psmouse->private;
 492         struct elantech_attr_data *attr = data;
 493         unsigned char *reg = (unsigned char *) etd + attr->field_offset;
 494         int rc = 0;
 495
 496         if (attr->reg)
 497                 rc = elantech_read_reg(psmouse, attr->reg, reg);
 498
 499         return sprintf(buf, "0x%02x\n", (attr->reg && rc) ? -1 : *reg);
 500 }
 501
 502 /*
 503  * Write a register value by writing a sysfs entry
 504  */
 505 static ssize_t elantech_set_int_attr(struct psmouse *psmouse,
 506                                      void *data, const char *buf, size_t count)
 507 {
 508         struct elantech_data *etd = psmouse->private;
 509         struct elantech_attr_data *attr = data;
 510         unsigned char *reg = (unsigned char *) etd + attr->field_offset;
 511         unsigned long value;
 512         int err;
 513
 514         err = strict_strtoul(buf, 16, &value);
 515         if (err)
 516                 return err;
 517
 518         if (value > 0xff)
 519                 return -EINVAL;
 520
 521         /* Do we need to preserve some bits for version 2 hardware too? */
 522         if (etd->hw_version == 1) {
 523                 if (attr->reg == 0x10)
 524                         /* Force absolute mode always on */
 525                         value |= ETP_R10_ABSOLUTE_MODE;
 526                 else if (attr->reg == 0x11)
 527                         /* Force 4 byte mode always on */
 528                         value |= ETP_R11_4_BYTE_MODE;
 529         }
 530
 531         if (!attr->reg || elantech_write_reg(psmouse, attr->reg, value) == 0)
 532                 *reg = value;
 533
 534         return count;
 535 }
 536
 537 #define ELANTECH_INT_ATTR(_name, _register)                             \
 538         static struct elantech_attr_data elantech_attr_##_name = {      \
 539                 .field_offset = offsetof(struct elantech_data, _name),  \
 540                 .reg = _register,                                       \
 541         };                                                              \
 542         PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,                   \
 543                             &elantech_attr_##_name,                     \
 544                             elantech_show_int_attr,                     \
 545                             elantech_set_int_attr)
 546
 547 ELANTECH_INT_ATTR(reg_10, 0x10);
 548 ELANTECH_INT_ATTR(reg_11, 0x11);
 549 ELANTECH_INT_ATTR(reg_20, 0x20);
 550 ELANTECH_INT_ATTR(reg_21, 0x21);
 551 ELANTECH_INT_ATTR(reg_22, 0x22);
 552 ELANTECH_INT_ATTR(reg_23, 0x23);
 553 ELANTECH_INT_ATTR(reg_24, 0x24);
 554 ELANTECH_INT_ATTR(reg_25, 0x25);
 555 ELANTECH_INT_ATTR(reg_26, 0x26);
 556 ELANTECH_INT_ATTR(debug, 0);
 557 ELANTECH_INT_ATTR(paritycheck, 0);
 558
 559 static struct attribute *elantech_attrs[] = {
 560         &psmouse_attr_reg_10.dattr.attr,
 561         &psmouse_attr_reg_11.dattr.attr,
 562         &psmouse_attr_reg_20.dattr.attr,
 563         &psmouse_attr_reg_21.dattr.attr,
 564         &psmouse_attr_reg_22.dattr.attr,
 565         &psmouse_attr_reg_23.dattr.attr,
 566         &psmouse_attr_reg_24.dattr.attr,
 567         &psmouse_attr_reg_25.dattr.attr,
 568         &psmouse_attr_reg_26.dattr.attr,
 569         &psmouse_attr_debug.dattr.attr,
 570         &psmouse_attr_paritycheck.dattr.attr,
 571         NULL
 572 };
 573
 574 static struct attribute_group elantech_attr_group = {
 575         .attrs = elantech_attrs,
 576 };
 577
 578 static bool elantech_is_signature_valid(const unsigned char *param)
 579 {
 580         static const unsigned char rates[] = { 200, 100, 80, 60, 40, 20, 10 };
 581         int i;
 582
 583         if (param[0] == 0)
 584                 return false;
 585
 586         if (param[1] == 0)
 587                 return true;
 588
 589         for (i = 0; i < ARRAY_SIZE(rates); i++)
 590                 if (param[2] == rates[i])
 591                         return false;
 592
 593         return true;
 594 }
 595
 596 /*
 597  * Use magic knock to detect Elantech touchpad
 598  */
 599 int elantech_detect(struct psmouse *psmouse, bool set_properties)
 600 {
 601         struct ps2dev *ps2dev = &psmouse->ps2dev;
 602         unsigned char param[3];
 603
 604         ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
 605
 606         if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_DISABLE) ||
 607             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 608             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 609             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11) ||
 610             ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
 611                 pr_debug("sending Elantech magic knock failed.\n");
 612                 return -1;
 613         }
 614
 615         /*
 616          * Report this in case there are Elantech models that use a different
 617          * set of magic numbers
 618          */
 619         if (param[0] != 0x3c || param[1] != 0x03 || param[2] != 0xc8) {
 620                 pr_debug("unexpected magic knock result 0x%02x, 0x%02x, 0x%02x.\n",
 621                          param[0], param[1], param[2]);
 622                 return -1;
 623         }
 624
 625         /*
 626          * Query touchpad's firmware version and see if it reports known
 627          * value to avoid mis-detection. Logitech mice are known to respond
 628          * to Elantech magic knock and there might be more.
 629          */
 630         if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
 631                 pr_debug("failed to query firmware version.\n");
 632                 return -1;
 633         }
 634
 635         pr_debug("Elantech version query result 0x%02x, 0x%02x, 0x%02x.\n",
 636                  param[0], param[1], param[2]);
 637
 638         if (!elantech_is_signature_valid(param)) {
 639                 if (!force_elantech) {
 640                         pr_debug("Probably not a real Elantech touchpad. Aborting.\n");
 641                         return -1;
 642                 }
 643
 644                 pr_debug("Probably not a real Elantech touchpad. Enabling anyway due to force_elantech.\n");
 645         }
 646
 647         if (set_properties) {
 648                 psmouse->vendor = "Elantech";
 649                 psmouse->name = "Touchpad";
 650         }
 651
 652         return 0;
 653 }
 654
 655 /*
 656  * Clean up sysfs entries when disconnecting
 657  */
 658 static void elantech_disconnect(struct psmouse *psmouse)
 659 {
 660         sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
 661                            &elantech_attr_group);
 662         kfree(psmouse->private);
 663         psmouse->private = NULL;
 664 }
 665
 666 /*
 667  * Put the touchpad back into absolute mode when reconnecting
 668  */
 669 static int elantech_reconnect(struct psmouse *psmouse)
 670 {
 671         if (elantech_detect(psmouse, 0))
 672                 return -1;
 673
 674         if (elantech_set_absolute_mode(psmouse)) {
 675                 pr_err("failed to put touchpad back into absolute mode.\n");
 676                 return -1;
 677         }
 678
 679         return 0;
 680 }
 681
 682 /*
 683  * Initialize the touchpad and create sysfs entries
 684  */
 685 int elantech_init(struct psmouse *psmouse)
 686 {
 687         struct elantech_data *etd;
 688         int i, error;
 689         unsigned char param[3];
 690
 691         psmouse->private = etd = kzalloc(sizeof(struct elantech_data), GFP_KERNEL);
 692         if (!etd)
 693                 return -1;
 694
 695         etd->parity[0] = 1;
 696         for (i = 1; i < 256; i++)
 697                 etd->parity[i] = etd->parity[i & (i - 1)] ^ 1;
 698
 699         /*
 700          * Do the version query again so we can store the result
 701          */
 702         if (synaptics_send_cmd(psmouse, ETP_FW_VERSION_QUERY, param)) {
 703                 pr_err("failed to query firmware version.\n");
 704                 goto init_fail;
 705         }
 706
 707         etd->fw_version = (param[0] << 16) | (param[1] << 8) | param[2];
 708
 709         /*
 710          * Assume every version greater than this is new EeePC style
 711          * hardware with 6 byte packets
 712          */
 713         if (etd->fw_version >= 0x020030) {
 714                 etd->hw_version = 2;
 715                 /* For now show extra debug information */
 716                 etd->debug = 1;
 717                 /* Don't know how to do parity checking for version 2 */
 718                 etd->paritycheck = 0;
 719         } else {
 720                 etd->hw_version = 1;
 721                 etd->paritycheck = 1;
 722         }
 723
 724         pr_info("assuming hardware version %d, firmware version %d.%d.%d\n",
 725                 etd->hw_version, param[0], param[1], param[2]);
 726
 727         if (synaptics_send_cmd(psmouse, ETP_CAPABILITIES_QUERY, param)) {
 728                 pr_err("failed to query capabilities.\n");
 729                 goto init_fail;
 730         }
 731         pr_info("Synaptics capabilities query result 0x%02x, 0x%02x, 0x%02x.\n",
 732                 param[0], param[1], param[2]);
 733         etd->capabilities = param[0];
 734
 735         /*
 736          * This firmware seems to suffer from misreporting coordinates when
 737          * a touch action starts causing the mouse cursor or scrolled page
 738          * to jump. Enable a workaround.
 739          */
 740         if (etd->fw_version == 0x020022) {
 741                 pr_info("firmware version 2.0.34 detected, enabling jumpy cursor workaround\n");
 742                 etd->jumpy_cursor = 1;
 743         }
 744
 745         if (elantech_set_absolute_mode(psmouse)) {
 746                 pr_err("failed to put touchpad into absolute mode.\n");
 747                 goto init_fail;
 748         }
 749
 750         elantech_set_input_params(psmouse);
 751
 752         error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
 753                                    &elantech_attr_group);
 754         if (error) {
 755                 pr_err("failed to create sysfs attributes, error: %d.\n", error);
 756                 goto init_fail;
 757         }
 758
 759         psmouse->protocol_handler = elantech_process_byte;
 760         psmouse->disconnect = elantech_disconnect;
 761         psmouse->reconnect = elantech_reconnect;
 762         psmouse->pktsize = etd->hw_version == 2 ? 6 : 4;
 763
 764         return 0;
 765
 766  init_fail:
 767         kfree(etd);
 768         return -1;
 769 }