drivers/input/mouse/hgpk.c

   1 /*
   2  * OLPC HGPK (XO-1) touchpad PS/2 mouse driver
   3  *
   4  * Copyright (c) 2006-2008 One Laptop Per Child
   5  * Authors:
   6  *   Zephaniah E. Hull
   7  *   Andres Salomon <dilinger@debian.org>
   8  *
   9  * This driver is partly based on the ALPS driver, which is:
  10  *
  11  * Copyright (c) 2003 Neil Brown <neilb@cse.unsw.edu.au>
  12  * Copyright (c) 2003-2005 Peter Osterlund <petero2@telia.com>
  13  * Copyright (c) 2004 Dmitry Torokhov <dtor@mail.ru>
  14  * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License version 2 as
  18  * published by the Free Software Foundation.
  19  */
  20
  21 /*
  22  * The spec from ALPS is available from
  23  * <http://wiki.laptop.org/go/Touch_Pad/Tablet>.  It refers to this
  24  * device as HGPK (Hybrid GS, PT, and Keymatrix).
  25  *
  26  * The earliest versions of the device had simultaneous reporting; that
  27  * was removed.  After that, the device used the Advanced Mode GS/PT streaming
  28  * stuff.  That turned out to be too buggy to support, so we've finally
  29  * switched to Mouse Mode (which utilizes only the center 1/3 of the touchpad).
  30  */
  31
  32 #define DEBUG
  33 #include <linux/slab.h>
  34 #include <linux/input.h>
  35 #include <linux/module.h>
  36 #include <linux/serio.h>
  37 #include <linux/libps2.h>
  38 #include <linux/delay.h>
  39 #include <asm/olpc.h>
  40
  41 #include "psmouse.h"
  42 #include "hgpk.h"
  43
  44 #define ILLEGAL_XY 999999
  45
  46 static bool tpdebug;
  47 module_param(tpdebug, bool, 0644);
  48 MODULE_PARM_DESC(tpdebug, "enable debugging, dumping packets to KERN_DEBUG.");
  49
  50 static int recalib_delta = 100;
  51 module_param(recalib_delta, int, 0644);
  52 MODULE_PARM_DESC(recalib_delta,
  53         "packets containing a delta this large will be discarded, and a "
  54         "recalibration may be scheduled.");
  55
  56 static int jumpy_delay = 20;
  57 module_param(jumpy_delay, int, 0644);
  58 MODULE_PARM_DESC(jumpy_delay,
  59         "delay (ms) before recal after jumpiness detected");
  60
  61 static int spew_delay = 1;
  62 module_param(spew_delay, int, 0644);
  63 MODULE_PARM_DESC(spew_delay,
  64         "delay (ms) before recal after packet spew detected");
  65
  66 static int recal_guard_time;
  67 module_param(recal_guard_time, int, 0644);
  68 MODULE_PARM_DESC(recal_guard_time,
  69         "interval (ms) during which recal will be restarted if packet received");
  70
  71 static int post_interrupt_delay = 40;
  72 module_param(post_interrupt_delay, int, 0644);
  73 MODULE_PARM_DESC(post_interrupt_delay,
  74         "delay (ms) before recal after recal interrupt detected");
  75
  76 static bool autorecal = true;
  77 module_param(autorecal, bool, 0644);
  78 MODULE_PARM_DESC(autorecal, "enable recalibration in the driver");
  79
  80 static char hgpk_mode_name[16];
  81 module_param_string(hgpk_mode, hgpk_mode_name, sizeof(hgpk_mode_name), 0644);
  82 MODULE_PARM_DESC(hgpk_mode,
  83         "default hgpk mode: mouse, glidesensor or pentablet");
  84
  85 static int hgpk_default_mode = HGPK_MODE_MOUSE;
  86
  87 static const char * const hgpk_mode_names[] = {
  88         [HGPK_MODE_MOUSE] = "Mouse",
  89         [HGPK_MODE_GLIDESENSOR] = "GlideSensor",
  90         [HGPK_MODE_PENTABLET] = "PenTablet",
  91 };
  92
  93 static int hgpk_mode_from_name(const char *buf, int len)
  94 {
  95         int i;
  96
  97         for (i = 0; i < ARRAY_SIZE(hgpk_mode_names); i++) {
  98                 const char *name = hgpk_mode_names[i];
  99                 if (strlen(name) == len && !strncasecmp(name, buf, len))
 100                         return i;
 101         }
 102
 103         return HGPK_MODE_INVALID;
 104 }
 105
 106 /*
 107  * see if new value is within 20% of half of old value
 108  */
 109 static int approx_half(int curr, int prev)
 110 {
 111         int belowhalf, abovehalf;
 112
 113         if (curr < 5 || prev < 5)
 114                 return 0;
 115
 116         belowhalf = (prev * 8) / 20;
 117         abovehalf = (prev * 12) / 20;
 118
 119         return belowhalf < curr && curr <= abovehalf;
 120 }
 121
 122 /*
 123  * Throw out oddly large delta packets, and any that immediately follow whose
 124  * values are each approximately half of the previous.  It seems that the ALPS
 125  * firmware emits errant packets, and they get averaged out slowly.
 126  */
 127 static int hgpk_discard_decay_hack(struct psmouse *psmouse, int x, int y)
 128 {
 129         struct hgpk_data *priv = psmouse->private;
 130         int avx, avy;
 131         bool do_recal = false;
 132
 133         avx = abs(x);
 134         avy = abs(y);
 135
 136         /* discard if too big, or half that but > 4 times the prev delta */
 137         if (avx > recalib_delta ||
 138                 (avx > recalib_delta / 2 && ((avx / 4) > priv->xlast))) {
 139                 hgpk_err(psmouse, "detected %dpx jump in x\n", x);
 140                 priv->xbigj = avx;
 141         } else if (approx_half(avx, priv->xbigj)) {
 142                 hgpk_err(psmouse, "detected secondary %dpx jump in x\n", x);
 143                 priv->xbigj = avx;
 144                 priv->xsaw_secondary++;
 145         } else {
 146                 if (priv->xbigj && priv->xsaw_secondary > 1)
 147                         do_recal = true;
 148                 priv->xbigj = 0;
 149                 priv->xsaw_secondary = 0;
 150         }
 151
 152         if (avy > recalib_delta ||
 153                 (avy > recalib_delta / 2 && ((avy / 4) > priv->ylast))) {
 154                 hgpk_err(psmouse, "detected %dpx jump in y\n", y);
 155                 priv->ybigj = avy;
 156         } else if (approx_half(avy, priv->ybigj)) {
 157                 hgpk_err(psmouse, "detected secondary %dpx jump in y\n", y);
 158                 priv->ybigj = avy;
 159                 priv->ysaw_secondary++;
 160         } else {
 161                 if (priv->ybigj && priv->ysaw_secondary > 1)
 162                         do_recal = true;
 163                 priv->ybigj = 0;
 164                 priv->ysaw_secondary = 0;
 165         }
 166
 167         priv->xlast = avx;
 168         priv->ylast = avy;
 169
 170         if (do_recal && jumpy_delay) {
 171                 hgpk_err(psmouse, "scheduling recalibration\n");
 172                 psmouse_queue_work(psmouse, &priv->recalib_wq,
 173                                 msecs_to_jiffies(jumpy_delay));
 174         }
 175
 176         return priv->xbigj || priv->ybigj;
 177 }
 178
 179 static void hgpk_reset_spew_detection(struct hgpk_data *priv)
 180 {
 181         priv->spew_count = 0;
 182         priv->dupe_count = 0;
 183         priv->x_tally = 0;
 184         priv->y_tally = 0;
 185         priv->spew_flag = NO_SPEW;
 186 }
 187
 188 static void hgpk_reset_hack_state(struct psmouse *psmouse)
 189 {
 190         struct hgpk_data *priv = psmouse->private;
 191
 192         priv->abs_x = priv->abs_y = -1;
 193         priv->xlast = priv->ylast = ILLEGAL_XY;
 194         priv->xbigj = priv->ybigj = 0;
 195         priv->xsaw_secondary = priv->ysaw_secondary = 0;
 196         hgpk_reset_spew_detection(priv);
 197 }
 198
 199 /*
 200  * We have no idea why this particular hardware bug occurs.  The touchpad
 201  * will randomly start spewing packets without anything touching the
 202  * pad.  This wouldn't necessarily be bad, but it's indicative of a
 203  * severely miscalibrated pad; attempting to use the touchpad while it's
 204  * spewing means the cursor will jump all over the place, and act "drunk".
 205  *
 206  * The packets that are spewed tend to all have deltas between -2 and 2, and
 207  * the cursor will move around without really going very far.  It will
 208  * tend to end up in the same location; if we tally up the changes over
 209  * 100 packets, we end up w/ a final delta of close to 0.  This happens
 210  * pretty regularly when the touchpad is spewing, and is pretty hard to
 211  * manually trigger (at least for *my* fingers).  So, it makes a perfect
 212  * scheme for detecting spews.
 213  */
 214 static void hgpk_spewing_hack(struct psmouse *psmouse,
 215                               int l, int r, int x, int y)
 216 {
 217         struct hgpk_data *priv = psmouse->private;
 218
 219         /* ignore button press packets; many in a row could trigger
 220          * a false-positive! */
 221         if (l || r)
 222                 return;
 223
 224         /* don't track spew if the workaround feature has been turned off */
 225         if (!spew_delay)
 226                 return;
 227
 228         if (abs(x) > 3 || abs(y) > 3) {
 229                 /* no spew, or spew ended */
 230                 hgpk_reset_spew_detection(priv);
 231                 return;
 232         }
 233
 234         /* Keep a tally of the overall delta to the cursor position caused by
 235          * the spew */
 236         priv->x_tally += x;
 237         priv->y_tally += y;
 238
 239         switch (priv->spew_flag) {
 240         case NO_SPEW:
 241                 /* we're not spewing, but this packet might be the start */
 242                 priv->spew_flag = MAYBE_SPEWING;
 243
 244                 /* fall-through */
 245
 246         case MAYBE_SPEWING:
 247                 priv->spew_count++;
 248
 249                 if (priv->spew_count < SPEW_WATCH_COUNT)
 250                         break;
 251
 252                 /* excessive spew detected, request recalibration */
 253                 priv->spew_flag = SPEW_DETECTED;
 254
 255                 /* fall-through */
 256
 257         case SPEW_DETECTED:
 258                 /* only recalibrate when the overall delta to the cursor
 259                  * is really small. if the spew is causing significant cursor
 260                  * movement, it is probably a case of the user moving the
 261                  * cursor very slowly across the screen. */
 262                 if (abs(priv->x_tally) < 3 && abs(priv->y_tally) < 3) {
 263                         hgpk_err(psmouse, "packet spew detected (%d,%d)\n",
 264                                  priv->x_tally, priv->y_tally);
 265                         priv->spew_flag = RECALIBRATING;
 266                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 267                                            msecs_to_jiffies(spew_delay));
 268                 }
 269
 270                 break;
 271         case RECALIBRATING:
 272                 /* we already detected a spew and requested a recalibration,
 273                  * just wait for the queue to kick into action. */
 274                 break;
 275         }
 276 }
 277
 278 /*
 279  * HGPK Mouse Mode format (standard mouse format, sans middle button)
 280  *
 281  * byte 0:      y-over  x-over  y-neg   x-neg   1       0       swr     swl
 282  * byte 1:      x7      x6      x5      x4      x3      x2      x1      x0
 283  * byte 2:      y7      y6      y5      y4      y3      y2      y1      y0
 284  *
 285  * swr/swl are the left/right buttons.
 286  * x-neg/y-neg are the x and y delta negative bits
 287  * x-over/y-over are the x and y overflow bits
 288  *
 289  * ---
 290  *
 291  * HGPK Advanced Mode - single-mode format
 292  *
 293  * byte 0(PT):  1    1    0    0    1    1     1     1
 294  * byte 0(GS):  1    1    1    1    1    1     1     1
 295  * byte 1:      0   x6   x5   x4   x3   x2    x1    x0
 296  * byte 2(PT):  0    0   x9   x8   x7    ? pt-dsw    0
 297  * byte 2(GS):  0  x10   x9   x8   x7    ? gs-dsw pt-dsw
 298  * byte 3:      0   y9   y8   y7    1    0   swr   swl
 299  * byte 4:      0   y6   y5   y4   y3   y2    y1    y0
 300  * byte 5:      0   z6   z5   z4   z3   z2    z1    z0
 301  *
 302  * ?'s are not defined in the protocol spec, may vary between models.
 303  *
 304  * swr/swl are the left/right buttons.
 305  *
 306  * pt-dsw/gs-dsw indicate that the pt/gs sensor is detecting a
 307  * pen/finger
 308  */
 309 static bool hgpk_is_byte_valid(struct psmouse *psmouse, unsigned char *packet)
 310 {
 311         struct hgpk_data *priv = psmouse->private;
 312         int pktcnt = psmouse->pktcnt;
 313         bool valid;
 314
 315         switch (priv->mode) {
 316         case HGPK_MODE_MOUSE:
 317                 valid = (packet[0] & 0x0C) == 0x08;
 318                 break;
 319
 320         case HGPK_MODE_GLIDESENSOR:
 321                 valid = pktcnt == 1 ?
 322                         packet[0] == HGPK_GS : !(packet[pktcnt - 1] & 0x80);
 323                 break;
 324
 325         case HGPK_MODE_PENTABLET:
 326                 valid = pktcnt == 1 ?
 327                         packet[0] == HGPK_PT : !(packet[pktcnt - 1] & 0x80);
 328                 break;
 329
 330         default:
 331                 valid = false;
 332                 break;
 333         }
 334
 335         if (!valid)
 336                 hgpk_dbg(psmouse,
 337                          "bad data, mode %d (%d) %02x %02x %02x %02x %02x %02x\n",
 338                          priv->mode, pktcnt,
 339                          psmouse->packet[0], psmouse->packet[1],
 340                          psmouse->packet[2], psmouse->packet[3],
 341                          psmouse->packet[4], psmouse->packet[5]);
 342
 343         return valid;
 344 }
 345
 346 static void hgpk_process_advanced_packet(struct psmouse *psmouse)
 347 {
 348         struct hgpk_data *priv = psmouse->private;
 349         struct input_dev *idev = psmouse->dev;
 350         unsigned char *packet = psmouse->packet;
 351         int down = !!(packet[2] & 2);
 352         int left = !!(packet[3] & 1);
 353         int right = !!(packet[3] & 2);
 354         int x = packet[1] | ((packet[2] & 0x78) << 4);
 355         int y = packet[4] | ((packet[3] & 0x70) << 3);
 356
 357         if (priv->mode == HGPK_MODE_GLIDESENSOR) {
 358                 int pt_down = !!(packet[2] & 1);
 359                 int finger_down = !!(packet[2] & 2);
 360                 int z = packet[5];
 361
 362                 input_report_abs(idev, ABS_PRESSURE, z);
 363                 if (tpdebug)
 364                         hgpk_dbg(psmouse, "pd=%d fd=%d z=%d",
 365                                  pt_down, finger_down, z);
 366         } else {
 367                 /*
 368                  * PenTablet mode does not report pressure, so we don't
 369                  * report it here
 370                  */
 371                 if (tpdebug)
 372                         hgpk_dbg(psmouse, "pd=%d ", down);
 373         }
 374
 375         if (tpdebug)
 376                 hgpk_dbg(psmouse, "l=%d r=%d x=%d y=%d\n", left, right, x, y);
 377
 378         input_report_key(idev, BTN_TOUCH, down);
 379         input_report_key(idev, BTN_LEFT, left);
 380         input_report_key(idev, BTN_RIGHT, right);
 381
 382         /*
 383          * If this packet says that the finger was removed, reset our position
 384          * tracking so that we don't erroneously detect a jump on next press.
 385          */
 386         if (!down) {
 387                 hgpk_reset_hack_state(psmouse);
 388                 goto done;
 389         }
 390
 391         /*
 392          * Weed out duplicate packets (we get quite a few, and they mess up
 393          * our jump detection)
 394          */
 395         if (x == priv->abs_x && y == priv->abs_y) {
 396                 if (++priv->dupe_count > SPEW_WATCH_COUNT) {
 397                         if (tpdebug)
 398                                 hgpk_dbg(psmouse, "hard spew detected\n");
 399                         priv->spew_flag = RECALIBRATING;
 400                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 401                                            msecs_to_jiffies(spew_delay));
 402                 }
 403                 goto done;
 404         }
 405
 406         /* not a duplicate, continue with position reporting */
 407         priv->dupe_count = 0;
 408
 409         /* Don't apply hacks in PT mode, it seems reliable */
 410         if (priv->mode != HGPK_MODE_PENTABLET && priv->abs_x != -1) {
 411                 int x_diff = priv->abs_x - x;
 412                 int y_diff = priv->abs_y - y;
 413                 if (hgpk_discard_decay_hack(psmouse, x_diff, y_diff)) {
 414                         if (tpdebug)
 415                                 hgpk_dbg(psmouse, "discarding\n");
 416                         goto done;
 417                 }
 418                 hgpk_spewing_hack(psmouse, left, right, x_diff, y_diff);
 419         }
 420
 421         input_report_abs(idev, ABS_X, x);
 422         input_report_abs(idev, ABS_Y, y);
 423         priv->abs_x = x;
 424         priv->abs_y = y;
 425
 426 done:
 427         input_sync(idev);
 428 }
 429
 430 static void hgpk_process_simple_packet(struct psmouse *psmouse)
 431 {
 432         struct input_dev *dev = psmouse->dev;
 433         unsigned char *packet = psmouse->packet;
 434         int left = packet[0] & 1;
 435         int right = (packet[0] >> 1) & 1;
 436         int x = packet[1] - ((packet[0] << 4) & 0x100);
 437         int y = ((packet[0] << 3) & 0x100) - packet[2];
 438
 439         if (packet[0] & 0xc0)
 440                 hgpk_dbg(psmouse,
 441                          "overflow -- 0x%02x 0x%02x 0x%02x\n",
 442                          packet[0], packet[1], packet[2]);
 443
 444         if (hgpk_discard_decay_hack(psmouse, x, y)) {
 445                 if (tpdebug)
 446                         hgpk_dbg(psmouse, "discarding\n");
 447                 return;
 448         }
 449
 450         hgpk_spewing_hack(psmouse, left, right, x, y);
 451
 452         if (tpdebug)
 453                 hgpk_dbg(psmouse, "l=%d r=%d x=%d y=%d\n", left, right, x, y);
 454
 455         input_report_key(dev, BTN_LEFT, left);
 456         input_report_key(dev, BTN_RIGHT, right);
 457
 458         input_report_rel(dev, REL_X, x);
 459         input_report_rel(dev, REL_Y, y);
 460
 461         input_sync(dev);
 462 }
 463
 464 static psmouse_ret_t hgpk_process_byte(struct psmouse *psmouse)
 465 {
 466         struct hgpk_data *priv = psmouse->private;
 467
 468         if (!hgpk_is_byte_valid(psmouse, psmouse->packet))
 469                 return PSMOUSE_BAD_DATA;
 470
 471         if (psmouse->pktcnt >= psmouse->pktsize) {
 472                 if (priv->mode == HGPK_MODE_MOUSE)
 473                         hgpk_process_simple_packet(psmouse);
 474                 else
 475                         hgpk_process_advanced_packet(psmouse);
 476                 return PSMOUSE_FULL_PACKET;
 477         }
 478
 479         if (priv->recalib_window) {
 480                 if (time_before(jiffies, priv->recalib_window)) {
 481                         /*
 482                          * ugh, got a packet inside our recalibration
 483                          * window, schedule another recalibration.
 484                          */
 485                         hgpk_dbg(psmouse,
 486                                  "packet inside calibration window, "
 487                                  "queueing another recalibration\n");
 488                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 489                                         msecs_to_jiffies(post_interrupt_delay));
 490                 }
 491                 priv->recalib_window = 0;
 492         }
 493
 494         return PSMOUSE_GOOD_DATA;
 495 }
 496
 497 static int hgpk_select_mode(struct psmouse *psmouse)
 498 {
 499         struct ps2dev *ps2dev = &psmouse->ps2dev;
 500         struct hgpk_data *priv = psmouse->private;
 501         int i;
 502         int cmd;
 503
 504         /*
 505          * 4 disables to enable advanced mode
 506          * then 3 0xf2 bytes as the preamble for GS/PT selection
 507          */
 508         const int advanced_init[] = {
 509                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 510                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 511                 0xf2, 0xf2, 0xf2,
 512         };
 513
 514         switch (priv->mode) {
 515         case HGPK_MODE_MOUSE:
 516                 psmouse->pktsize = 3;
 517                 break;
 518
 519         case HGPK_MODE_GLIDESENSOR:
 520         case HGPK_MODE_PENTABLET:
 521                 psmouse->pktsize = 6;
 522
 523                 /* Switch to 'Advanced mode.', four disables in a row. */
 524                 for (i = 0; i < ARRAY_SIZE(advanced_init); i++)
 525                         if (ps2_command(ps2dev, NULL, advanced_init[i]))
 526                                 return -EIO;
 527
 528                 /* select between GlideSensor (mouse) or PenTablet */
 529                 cmd = priv->mode == HGPK_MODE_GLIDESENSOR ?
 530                         PSMOUSE_CMD_SETSCALE11 : PSMOUSE_CMD_SETSCALE21;
 531
 532                 if (ps2_command(ps2dev, NULL, cmd))
 533                         return -EIO;
 534                 break;
 535
 536         default:
 537                 return -EINVAL;
 538         }
 539
 540         return 0;
 541 }
 542
 543 static void hgpk_setup_input_device(struct input_dev *input,
 544                                     struct input_dev *old_input,
 545                                     enum hgpk_mode mode)
 546 {
 547         if (old_input) {
 548                 input->name = old_input->name;
 549                 input->phys = old_input->phys;
 550                 input->id = old_input->id;
 551                 input->dev.parent = old_input->dev.parent;
 552         }
 553
 554         memset(input->evbit, 0, sizeof(input->evbit));
 555         memset(input->relbit, 0, sizeof(input->relbit));
 556         memset(input->keybit, 0, sizeof(input->keybit));
 557
 558         /* All modes report left and right buttons */
 559         __set_bit(EV_KEY, input->evbit);
 560         __set_bit(BTN_LEFT, input->keybit);
 561         __set_bit(BTN_RIGHT, input->keybit);
 562
 563         switch (mode) {
 564         case HGPK_MODE_MOUSE:
 565                 __set_bit(EV_REL, input->evbit);
 566                 __set_bit(REL_X, input->relbit);
 567                 __set_bit(REL_Y, input->relbit);
 568                 break;
 569
 570         case HGPK_MODE_GLIDESENSOR:
 571                 __set_bit(BTN_TOUCH, input->keybit);
 572                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 573
 574                 __set_bit(EV_ABS, input->evbit);
 575
 576                 /* GlideSensor has pressure sensor, PenTablet does not */
 577                 input_set_abs_params(input, ABS_PRESSURE, 0, 15, 0, 0);
 578
 579                 /* From device specs */
 580                 input_set_abs_params(input, ABS_X, 0, 399, 0, 0);
 581                 input_set_abs_params(input, ABS_Y, 0, 290, 0, 0);
 582
 583                 /* Calculated by hand based on usable size (52mm x 38mm) */
 584                 input_abs_set_res(input, ABS_X, 8);
 585                 input_abs_set_res(input, ABS_Y, 8);
 586                 break;
 587
 588         case HGPK_MODE_PENTABLET:
 589                 __set_bit(BTN_TOUCH, input->keybit);
 590                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 591
 592                 __set_bit(EV_ABS, input->evbit);
 593
 594                 /* From device specs */
 595                 input_set_abs_params(input, ABS_X, 0, 999, 0, 0);
 596                 input_set_abs_params(input, ABS_Y, 5, 239, 0, 0);
 597
 598                 /* Calculated by hand based on usable size (156mm x 38mm) */
 599                 input_abs_set_res(input, ABS_X, 6);
 600                 input_abs_set_res(input, ABS_Y, 8);
 601                 break;
 602
 603         default:
 604                 BUG();
 605         }
 606 }
 607
 608 static int hgpk_reset_device(struct psmouse *psmouse, bool recalibrate)
 609 {
 610         int err;
 611
 612         psmouse_reset(psmouse);
 613
 614         if (recalibrate) {
 615                 struct ps2dev *ps2dev = &psmouse->ps2dev;
 616
 617                 /* send the recalibrate request */
 618                 if (ps2_command(ps2dev, NULL, 0xf5) ||
 619                     ps2_command(ps2dev, NULL, 0xf5) ||
 620                     ps2_command(ps2dev, NULL, 0xe6) ||
 621                     ps2_command(ps2dev, NULL, 0xf5)) {
 622                         return -1;
 623                 }
 624
 625                 /* according to ALPS, 150mS is required for recalibration */
 626                 msleep(150);
 627         }
 628
 629         err = hgpk_select_mode(psmouse);
 630         if (err) {
 631                 hgpk_err(psmouse, "failed to select mode\n");
 632                 return err;
 633         }
 634
 635         hgpk_reset_hack_state(psmouse);
 636
 637         return 0;
 638 }
 639
 640 static int hgpk_force_recalibrate(struct psmouse *psmouse)
 641 {
 642         struct ps2dev *ps2dev = &psmouse->ps2dev;
 643         struct hgpk_data *priv = psmouse->private;
 644         int err;
 645
 646         /* C-series touchpads added the recalibrate command */
 647         if (psmouse->model < HGPK_MODEL_C)
 648                 return 0;
 649
 650         if (!autorecal) {
 651                 hgpk_dbg(psmouse, "recalibrations disabled, ignoring\n");
 652                 return 0;
 653         }
 654
 655         hgpk_dbg(psmouse, "recalibrating touchpad..\n");
 656
 657         /* we don't want to race with the irq handler, nor with resyncs */
 658         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 659
 660         /* start by resetting the device */
 661         err = hgpk_reset_device(psmouse, true);
 662         if (err)
 663                 return err;
 664
 665         /*
 666          * XXX: If a finger is down during this delay, recalibration will
 667          * detect capacitance incorrectly.  This is a hardware bug, and
 668          * we don't have a good way to deal with it.  The 2s window stuff
 669          * (below) is our best option for now.
 670          */
 671
 672         if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE))
 673                 return -1;
 674
 675         psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
 676
 677         if (tpdebug)
 678                 hgpk_dbg(psmouse, "touchpad reactivated\n");
 679
 680         /*
 681          * If we get packets right away after recalibrating, it's likely
 682          * that a finger was on the touchpad.  If so, it's probably
 683          * miscalibrated, so we optionally schedule another.
 684          */
 685         if (recal_guard_time)
 686                 priv->recalib_window = jiffies +
 687                         msecs_to_jiffies(recal_guard_time);
 688
 689         return 0;
 690 }
 691
 692 /*
 693  * This puts the touchpad in a power saving mode; according to ALPS, current
 694  * consumption goes down to 50uA after running this.  To turn power back on,
 695  * we drive MS-DAT low.  Measuring with a 1mA resolution ammeter says that
 696  * the current on the SUS_3.3V rail drops from 3mA or 4mA to 0 when we do this.
 697  *
 698  * We have no formal spec that details this operation -- the low-power
 699  * sequence came from a long-lost email trail.
 700  */
 701 static int hgpk_toggle_powersave(struct psmouse *psmouse, int enable)
 702 {
 703         struct ps2dev *ps2dev = &psmouse->ps2dev;
 704         int timeo;
 705         int err;
 706
 707         /* Added on D-series touchpads */
 708         if (psmouse->model < HGPK_MODEL_D)
 709                 return 0;
 710
 711         if (enable) {
 712                 psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 713
 714                 /*
 715                  * Sending a byte will drive MS-DAT low; this will wake up
 716                  * the controller.  Once we get an ACK back from it, it
 717                  * means we can continue with the touchpad re-init.  ALPS
 718                  * tells us that 1s should be long enough, so set that as
 719                  * the upper bound. (in practice, it takes about 3 loops.)
 720                  */
 721                 for (timeo = 20; timeo > 0; timeo--) {
 722                         if (!ps2_sendbyte(&psmouse->ps2dev,
 723                                         PSMOUSE_CMD_DISABLE, 20))
 724                                 break;
 725                         msleep(25);
 726                 }
 727
 728                 err = hgpk_reset_device(psmouse, false);
 729                 if (err) {
 730                         hgpk_err(psmouse, "Failed to reset device!\n");
 731                         return err;
 732                 }
 733
 734                 /* should be all set, enable the touchpad */
 735                 ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);
 736                 psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
 737                 hgpk_dbg(psmouse, "Touchpad powered up.\n");
 738         } else {
 739                 hgpk_dbg(psmouse, "Powering off touchpad.\n");
 740
 741                 if (ps2_command(ps2dev, NULL, 0xec) ||
 742                     ps2_command(ps2dev, NULL, 0xec) ||
 743                     ps2_command(ps2dev, NULL, 0xea)) {
 744                         return -1;
 745                 }
 746
 747                 psmouse_set_state(psmouse, PSMOUSE_IGNORE);
 748
 749                 /* probably won't see an ACK, the touchpad will be off */
 750                 ps2_sendbyte(&psmouse->ps2dev, 0xec, 20);
 751         }
 752
 753         return 0;
 754 }
 755
 756 static int hgpk_poll(struct psmouse *psmouse)
 757 {
 758         /* We can't poll, so always return failure. */
 759         return -1;
 760 }
 761
 762 static int hgpk_reconnect(struct psmouse *psmouse)
 763 {
 764         struct hgpk_data *priv = psmouse->private;
 765
 766         /*
 767          * During suspend/resume the ps2 rails remain powered.  We don't want
 768          * to do a reset because it's flush data out of buffers; however,
 769          * earlier prototypes (B1) had some brokenness that required a reset.
 770          */
 771         if (olpc_board_at_least(olpc_board(0xb2)))
 772                 if (psmouse->ps2dev.serio->dev.power.power_state.event !=
 773                                 PM_EVENT_ON)
 774                         return 0;
 775
 776         priv->powered = 1;
 777         return hgpk_reset_device(psmouse, false);
 778 }
 779
 780 static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char *buf)
 781 {
 782         struct hgpk_data *priv = psmouse->private;
 783
 784         return sprintf(buf, "%d\n", priv->powered);
 785 }
 786
 787 static ssize_t hgpk_set_powered(struct psmouse *psmouse, void *data,
 788                                 const char *buf, size_t count)
 789 {
 790         struct hgpk_data *priv = psmouse->private;
 791         unsigned long value;
 792         int err;
 793
 794         err = strict_strtoul(buf, 10, &value);
 795         if (err || value > 1)
 796                 return -EINVAL;
 797
 798         if (value != priv->powered) {
 799                 /*
 800                  * hgpk_toggle_power will deal w/ state so
 801                  * we're not racing w/ irq
 802                  */
 803                 err = hgpk_toggle_powersave(psmouse, value);
 804                 if (!err)
 805                         priv->powered = value;
 806         }
 807
 808         return err ? err : count;
 809 }
 810
 811 __PSMOUSE_DEFINE_ATTR(powered, S_IWUSR | S_IRUGO, NULL,
 812                       hgpk_show_powered, hgpk_set_powered, false);
 813
 814 static ssize_t attr_show_mode(struct psmouse *psmouse, void *data, char *buf)
 815 {
 816         struct hgpk_data *priv = psmouse->private;
 817
 818         return sprintf(buf, "%s\n", hgpk_mode_names[priv->mode]);
 819 }
 820
 821 static ssize_t attr_set_mode(struct psmouse *psmouse, void *data,
 822                              const char *buf, size_t len)
 823 {
 824         struct hgpk_data *priv = psmouse->private;
 825         enum hgpk_mode old_mode = priv->mode;
 826         enum hgpk_mode new_mode = hgpk_mode_from_name(buf, len);
 827         struct input_dev *old_dev = psmouse->dev;
 828         struct input_dev *new_dev;
 829         int err;
 830
 831         if (new_mode == HGPK_MODE_INVALID)
 832                 return -EINVAL;
 833
 834         if (old_mode == new_mode)
 835                 return len;
 836
 837         new_dev = input_allocate_device();
 838         if (!new_dev)
 839                 return -ENOMEM;
 840
 841         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 842
 843         /* Switch device into the new mode */
 844         priv->mode = new_mode;
 845         err = hgpk_reset_device(psmouse, false);
 846         if (err)
 847                 goto err_try_restore;
 848
 849         hgpk_setup_input_device(new_dev, old_dev, new_mode);
 850
 851         psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
 852
 853         err = input_register_device(new_dev);
 854         if (err)
 855                 goto err_try_restore;
 856
 857         psmouse->dev = new_dev;
 858         input_unregister_device(old_dev);
 859
 860         return len;
 861
 862 err_try_restore:
 863         input_free_device(new_dev);
 864         priv->mode = old_mode;
 865         hgpk_reset_device(psmouse, false);
 866
 867         return err;
 868 }
 869
 870 PSMOUSE_DEFINE_ATTR(hgpk_mode, S_IWUSR | S_IRUGO, NULL,
 871                     attr_show_mode, attr_set_mode);
 872
 873 static ssize_t hgpk_trigger_recal_show(struct psmouse *psmouse,
 874                 void *data, char *buf)
 875 {
 876         return -EINVAL;
 877 }
 878
 879 static ssize_t hgpk_trigger_recal(struct psmouse *psmouse, void *data,
 880                                 const char *buf, size_t count)
 881 {
 882         struct hgpk_data *priv = psmouse->private;
 883         unsigned long value;
 884         int err;
 885
 886         err = strict_strtoul(buf, 10, &value);
 887         if (err || value != 1)
 888                 return -EINVAL;
 889
 890         /*
 891          * We queue work instead of doing recalibration right here
 892          * to avoid adding locking to to hgpk_force_recalibrate()
 893          * since workqueue provides serialization.
 894          */
 895         psmouse_queue_work(psmouse, &priv->recalib_wq, 0);
 896         return count;
 897 }
 898
 899 __PSMOUSE_DEFINE_ATTR(recalibrate, S_IWUSR | S_IRUGO, NULL,
 900                       hgpk_trigger_recal_show, hgpk_trigger_recal, false);
 901
 902 static void hgpk_disconnect(struct psmouse *psmouse)
 903 {
 904         struct hgpk_data *priv = psmouse->private;
 905
 906         device_remove_file(&psmouse->ps2dev.serio->dev,
 907                            &psmouse_attr_powered.dattr);
 908         device_remove_file(&psmouse->ps2dev.serio->dev,
 909                            &psmouse_attr_hgpk_mode.dattr);
 910
 911         if (psmouse->model >= HGPK_MODEL_C)
 912                 device_remove_file(&psmouse->ps2dev.serio->dev,
 913                                    &psmouse_attr_recalibrate.dattr);
 914
 915         psmouse_reset(psmouse);
 916         kfree(priv);
 917 }
 918
 919 static void hgpk_recalib_work(struct work_struct *work)
 920 {
 921         struct delayed_work *w = to_delayed_work(work);
 922         struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq);
 923         struct psmouse *psmouse = priv->psmouse;
 924
 925         if (hgpk_force_recalibrate(psmouse))
 926                 hgpk_err(psmouse, "recalibration failed!\n");
 927 }
 928
 929 static int hgpk_register(struct psmouse *psmouse)
 930 {
 931         struct hgpk_data *priv = psmouse->private;
 932         int err;
 933
 934         /* register handlers */
 935         psmouse->protocol_handler = hgpk_process_byte;
 936         psmouse->poll = hgpk_poll;
 937         psmouse->disconnect = hgpk_disconnect;
 938         psmouse->reconnect = hgpk_reconnect;
 939
 940         /* Disable the idle resync. */
 941         psmouse->resync_time = 0;
 942         /* Reset after a lot of bad bytes. */
 943         psmouse->resetafter = 1024;
 944
 945         hgpk_setup_input_device(psmouse->dev, NULL, priv->mode);
 946
 947         err = device_create_file(&psmouse->ps2dev.serio->dev,
 948                                  &psmouse_attr_powered.dattr);
 949         if (err) {
 950                 hgpk_err(psmouse, "Failed creating 'powered' sysfs node\n");
 951                 return err;
 952         }
 953
 954         err = device_create_file(&psmouse->ps2dev.serio->dev,
 955                                  &psmouse_attr_hgpk_mode.dattr);
 956         if (err) {
 957                 hgpk_err(psmouse, "Failed creating 'hgpk_mode' sysfs node\n");
 958                 goto err_remove_powered;
 959         }
 960
 961         /* C-series touchpads added the recalibrate command */
 962         if (psmouse->model >= HGPK_MODEL_C) {
 963                 err = device_create_file(&psmouse->ps2dev.serio->dev,
 964                                          &psmouse_attr_recalibrate.dattr);
 965                 if (err) {
 966                         hgpk_err(psmouse,
 967                                 "Failed creating 'recalibrate' sysfs node\n");
 968                         goto err_remove_mode;
 969                 }
 970         }
 971
 972         return 0;
 973
 974 err_remove_mode:
 975         device_remove_file(&psmouse->ps2dev.serio->dev,
 976                            &psmouse_attr_hgpk_mode.dattr);
 977 err_remove_powered:
 978         device_remove_file(&psmouse->ps2dev.serio->dev,
 979                            &psmouse_attr_powered.dattr);
 980         return err;
 981 }
 982
 983 int hgpk_init(struct psmouse *psmouse)
 984 {
 985         struct hgpk_data *priv;
 986         int err;
 987
 988         priv = kzalloc(sizeof(struct hgpk_data), GFP_KERNEL);
 989         if (!priv) {
 990                 err = -ENOMEM;
 991                 goto alloc_fail;
 992         }
 993
 994         psmouse->private = priv;
 995
 996         priv->psmouse = psmouse;
 997         priv->powered = true;
 998         priv->mode = hgpk_default_mode;
 999         INIT_DELAYED_WORK(&priv->recalib_wq, hgpk_recalib_work);
1000
1001         err = hgpk_reset_device(psmouse, false);
1002         if (err)
1003                 goto init_fail;
1004
1005         err = hgpk_register(psmouse);
1006         if (err)
1007                 goto init_fail;
1008
1009         return 0;
1010
1011 init_fail:
1012         kfree(priv);
1013 alloc_fail:
1014         return err;
1015 }
1016
1017 static enum hgpk_model_t hgpk_get_model(struct psmouse *psmouse)
1018 {
1019         struct ps2dev *ps2dev = &psmouse->ps2dev;
1020         unsigned char param[3];
1021
1022         /* E7, E7, E7, E9 gets us a 3 byte identifier */
1023         if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1024             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1025             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1026             ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1027                 return -EIO;
1028         }
1029
1030         hgpk_dbg(psmouse, "ID: %02x %02x %02x\n", param[0], param[1], param[2]);
1031
1032         /* HGPK signature: 0x67, 0x00, 0x<model> */
1033         if (param[0] != 0x67 || param[1] != 0x00)
1034                 return -ENODEV;
1035
1036         hgpk_info(psmouse, "OLPC touchpad revision 0x%x\n", param[2]);
1037
1038         return param[2];
1039 }
1040
1041 int hgpk_detect(struct psmouse *psmouse, bool set_properties)
1042 {
1043         int version;
1044
1045         version = hgpk_get_model(psmouse);
1046         if (version < 0)
1047                 return version;
1048
1049         if (set_properties) {
1050                 psmouse->vendor = "ALPS";
1051                 psmouse->name = "HGPK";
1052                 psmouse->model = version;
1053         }
1054
1055         return 0;
1056 }
1057
1058 void hgpk_module_init(void)
1059 {
1060         hgpk_default_mode = hgpk_mode_from_name(hgpk_mode_name,
1061                                                 strlen(hgpk_mode_name));
1062         if (hgpk_default_mode == HGPK_MODE_INVALID) {
1063                 hgpk_default_mode = HGPK_MODE_MOUSE;
1064                 strlcpy(hgpk_mode_name, hgpk_mode_names[HGPK_MODE_MOUSE],
1065                         sizeof(hgpk_mode_name));
1066         }
1067 }