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                 psmouse_warn(psmouse, "detected %dpx jump in x\n", x);
 140                 priv->xbigj = avx;
 141         } else if (approx_half(avx, priv->xbigj)) {
 142                 psmouse_warn(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                 psmouse_warn(psmouse, "detected %dpx jump in y\n", y);
 155                 priv->ybigj = avy;
 156         } else if (approx_half(avy, priv->ybigj)) {
 157                 psmouse_warn(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                 psmouse_warn(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                         psmouse_warn(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                 psmouse_dbg(psmouse,
 337                             "bad data, mode %d (%d) %*ph\n",
 338                             priv->mode, pktcnt, 6, psmouse->packet);
 339
 340         return valid;
 341 }
 342
 343 static void hgpk_process_advanced_packet(struct psmouse *psmouse)
 344 {
 345         struct hgpk_data *priv = psmouse->private;
 346         struct input_dev *idev = psmouse->dev;
 347         unsigned char *packet = psmouse->packet;
 348         int down = !!(packet[2] & 2);
 349         int left = !!(packet[3] & 1);
 350         int right = !!(packet[3] & 2);
 351         int x = packet[1] | ((packet[2] & 0x78) << 4);
 352         int y = packet[4] | ((packet[3] & 0x70) << 3);
 353
 354         if (priv->mode == HGPK_MODE_GLIDESENSOR) {
 355                 int pt_down = !!(packet[2] & 1);
 356                 int finger_down = !!(packet[2] & 2);
 357                 int z = packet[5];
 358
 359                 input_report_abs(idev, ABS_PRESSURE, z);
 360                 if (tpdebug)
 361                         psmouse_dbg(psmouse, "pd=%d fd=%d z=%d",
 362                                     pt_down, finger_down, z);
 363         } else {
 364                 /*
 365                  * PenTablet mode does not report pressure, so we don't
 366                  * report it here
 367                  */
 368                 if (tpdebug)
 369                         psmouse_dbg(psmouse, "pd=%d ", down);
 370         }
 371
 372         if (tpdebug)
 373                 psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
 374                             left, right, x, y);
 375
 376         input_report_key(idev, BTN_TOUCH, down);
 377         input_report_key(idev, BTN_LEFT, left);
 378         input_report_key(idev, BTN_RIGHT, right);
 379
 380         /*
 381          * If this packet says that the finger was removed, reset our position
 382          * tracking so that we don't erroneously detect a jump on next press.
 383          */
 384         if (!down) {
 385                 hgpk_reset_hack_state(psmouse);
 386                 goto done;
 387         }
 388
 389         /*
 390          * Weed out duplicate packets (we get quite a few, and they mess up
 391          * our jump detection)
 392          */
 393         if (x == priv->abs_x && y == priv->abs_y) {
 394                 if (++priv->dupe_count > SPEW_WATCH_COUNT) {
 395                         if (tpdebug)
 396                                 psmouse_dbg(psmouse, "hard spew detected\n");
 397                         priv->spew_flag = RECALIBRATING;
 398                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 399                                            msecs_to_jiffies(spew_delay));
 400                 }
 401                 goto done;
 402         }
 403
 404         /* not a duplicate, continue with position reporting */
 405         priv->dupe_count = 0;
 406
 407         /* Don't apply hacks in PT mode, it seems reliable */
 408         if (priv->mode != HGPK_MODE_PENTABLET && priv->abs_x != -1) {
 409                 int x_diff = priv->abs_x - x;
 410                 int y_diff = priv->abs_y - y;
 411                 if (hgpk_discard_decay_hack(psmouse, x_diff, y_diff)) {
 412                         if (tpdebug)
 413                                 psmouse_dbg(psmouse, "discarding\n");
 414                         goto done;
 415                 }
 416                 hgpk_spewing_hack(psmouse, left, right, x_diff, y_diff);
 417         }
 418
 419         input_report_abs(idev, ABS_X, x);
 420         input_report_abs(idev, ABS_Y, y);
 421         priv->abs_x = x;
 422         priv->abs_y = y;
 423
 424 done:
 425         input_sync(idev);
 426 }
 427
 428 static void hgpk_process_simple_packet(struct psmouse *psmouse)
 429 {
 430         struct input_dev *dev = psmouse->dev;
 431         unsigned char *packet = psmouse->packet;
 432         int left = packet[0] & 1;
 433         int right = (packet[0] >> 1) & 1;
 434         int x = packet[1] - ((packet[0] << 4) & 0x100);
 435         int y = ((packet[0] << 3) & 0x100) - packet[2];
 436
 437         if (packet[0] & 0xc0)
 438                 psmouse_dbg(psmouse,
 439                             "overflow -- 0x%02x 0x%02x 0x%02x\n",
 440                             packet[0], packet[1], packet[2]);
 441
 442         if (hgpk_discard_decay_hack(psmouse, x, y)) {
 443                 if (tpdebug)
 444                         psmouse_dbg(psmouse, "discarding\n");
 445                 return;
 446         }
 447
 448         hgpk_spewing_hack(psmouse, left, right, x, y);
 449
 450         if (tpdebug)
 451                 psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
 452                             left, right, x, y);
 453
 454         input_report_key(dev, BTN_LEFT, left);
 455         input_report_key(dev, BTN_RIGHT, right);
 456
 457         input_report_rel(dev, REL_X, x);
 458         input_report_rel(dev, REL_Y, y);
 459
 460         input_sync(dev);
 461 }
 462
 463 static psmouse_ret_t hgpk_process_byte(struct psmouse *psmouse)
 464 {
 465         struct hgpk_data *priv = psmouse->private;
 466
 467         if (!hgpk_is_byte_valid(psmouse, psmouse->packet))
 468                 return PSMOUSE_BAD_DATA;
 469
 470         if (psmouse->pktcnt >= psmouse->pktsize) {
 471                 if (priv->mode == HGPK_MODE_MOUSE)
 472                         hgpk_process_simple_packet(psmouse);
 473                 else
 474                         hgpk_process_advanced_packet(psmouse);
 475                 return PSMOUSE_FULL_PACKET;
 476         }
 477
 478         if (priv->recalib_window) {
 479                 if (time_before(jiffies, priv->recalib_window)) {
 480                         /*
 481                          * ugh, got a packet inside our recalibration
 482                          * window, schedule another recalibration.
 483                          */
 484                         psmouse_dbg(psmouse,
 485                                     "packet inside calibration window, queueing another recalibration\n");
 486                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 487                                         msecs_to_jiffies(post_interrupt_delay));
 488                 }
 489                 priv->recalib_window = 0;
 490         }
 491
 492         return PSMOUSE_GOOD_DATA;
 493 }
 494
 495 static int hgpk_select_mode(struct psmouse *psmouse)
 496 {
 497         struct ps2dev *ps2dev = &psmouse->ps2dev;
 498         struct hgpk_data *priv = psmouse->private;
 499         int i;
 500         int cmd;
 501
 502         /*
 503          * 4 disables to enable advanced mode
 504          * then 3 0xf2 bytes as the preamble for GS/PT selection
 505          */
 506         const int advanced_init[] = {
 507                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 508                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 509                 0xf2, 0xf2, 0xf2,
 510         };
 511
 512         switch (priv->mode) {
 513         case HGPK_MODE_MOUSE:
 514                 psmouse->pktsize = 3;
 515                 break;
 516
 517         case HGPK_MODE_GLIDESENSOR:
 518         case HGPK_MODE_PENTABLET:
 519                 psmouse->pktsize = 6;
 520
 521                 /* Switch to 'Advanced mode.', four disables in a row. */
 522                 for (i = 0; i < ARRAY_SIZE(advanced_init); i++)
 523                         if (ps2_command(ps2dev, NULL, advanced_init[i]))
 524                                 return -EIO;
 525
 526                 /* select between GlideSensor (mouse) or PenTablet */
 527                 cmd = priv->mode == HGPK_MODE_GLIDESENSOR ?
 528                         PSMOUSE_CMD_SETSCALE11 : PSMOUSE_CMD_SETSCALE21;
 529
 530                 if (ps2_command(ps2dev, NULL, cmd))
 531                         return -EIO;
 532                 break;
 533
 534         default:
 535                 return -EINVAL;
 536         }
 537
 538         return 0;
 539 }
 540
 541 static void hgpk_setup_input_device(struct input_dev *input,
 542                                     struct input_dev *old_input,
 543                                     enum hgpk_mode mode)
 544 {
 545         if (old_input) {
 546                 input->name = old_input->name;
 547                 input->phys = old_input->phys;
 548                 input->id = old_input->id;
 549                 input->dev.parent = old_input->dev.parent;
 550         }
 551
 552         memset(input->evbit, 0, sizeof(input->evbit));
 553         memset(input->relbit, 0, sizeof(input->relbit));
 554         memset(input->keybit, 0, sizeof(input->keybit));
 555
 556         /* All modes report left and right buttons */
 557         __set_bit(EV_KEY, input->evbit);
 558         __set_bit(BTN_LEFT, input->keybit);
 559         __set_bit(BTN_RIGHT, input->keybit);
 560
 561         switch (mode) {
 562         case HGPK_MODE_MOUSE:
 563                 __set_bit(EV_REL, input->evbit);
 564                 __set_bit(REL_X, input->relbit);
 565                 __set_bit(REL_Y, input->relbit);
 566                 break;
 567
 568         case HGPK_MODE_GLIDESENSOR:
 569                 __set_bit(BTN_TOUCH, input->keybit);
 570                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 571
 572                 __set_bit(EV_ABS, input->evbit);
 573
 574                 /* GlideSensor has pressure sensor, PenTablet does not */
 575                 input_set_abs_params(input, ABS_PRESSURE, 0, 15, 0, 0);
 576
 577                 /* From device specs */
 578                 input_set_abs_params(input, ABS_X, 0, 399, 0, 0);
 579                 input_set_abs_params(input, ABS_Y, 0, 290, 0, 0);
 580
 581                 /* Calculated by hand based on usable size (52mm x 38mm) */
 582                 input_abs_set_res(input, ABS_X, 8);
 583                 input_abs_set_res(input, ABS_Y, 8);
 584                 break;
 585
 586         case HGPK_MODE_PENTABLET:
 587                 __set_bit(BTN_TOUCH, input->keybit);
 588                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 589
 590                 __set_bit(EV_ABS, input->evbit);
 591
 592                 /* From device specs */
 593                 input_set_abs_params(input, ABS_X, 0, 999, 0, 0);
 594                 input_set_abs_params(input, ABS_Y, 5, 239, 0, 0);
 595
 596                 /* Calculated by hand based on usable size (156mm x 38mm) */
 597                 input_abs_set_res(input, ABS_X, 6);
 598                 input_abs_set_res(input, ABS_Y, 8);
 599                 break;
 600
 601         default:
 602                 BUG();
 603         }
 604 }
 605
 606 static int hgpk_reset_device(struct psmouse *psmouse, bool recalibrate)
 607 {
 608         int err;
 609
 610         psmouse_reset(psmouse);
 611
 612         if (recalibrate) {
 613                 struct ps2dev *ps2dev = &psmouse->ps2dev;
 614
 615                 /* send the recalibrate request */
 616                 if (ps2_command(ps2dev, NULL, 0xf5) ||
 617                     ps2_command(ps2dev, NULL, 0xf5) ||
 618                     ps2_command(ps2dev, NULL, 0xe6) ||
 619                     ps2_command(ps2dev, NULL, 0xf5)) {
 620                         return -1;
 621                 }
 622
 623                 /* according to ALPS, 150mS is required for recalibration */
 624                 msleep(150);
 625         }
 626
 627         err = hgpk_select_mode(psmouse);
 628         if (err) {
 629                 psmouse_err(psmouse, "failed to select mode\n");
 630                 return err;
 631         }
 632
 633         hgpk_reset_hack_state(psmouse);
 634
 635         return 0;
 636 }
 637
 638 static int hgpk_force_recalibrate(struct psmouse *psmouse)
 639 {
 640         struct hgpk_data *priv = psmouse->private;
 641         int err;
 642
 643         /* C-series touchpads added the recalibrate command */
 644         if (psmouse->model < HGPK_MODEL_C)
 645                 return 0;
 646
 647         if (!autorecal) {
 648                 psmouse_dbg(psmouse, "recalibration disabled, ignoring\n");
 649                 return 0;
 650         }
 651
 652         psmouse_dbg(psmouse, "recalibrating touchpad..\n");
 653
 654         /* we don't want to race with the irq handler, nor with resyncs */
 655         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 656
 657         /* start by resetting the device */
 658         err = hgpk_reset_device(psmouse, true);
 659         if (err)
 660                 return err;
 661
 662         /*
 663          * XXX: If a finger is down during this delay, recalibration will
 664          * detect capacitance incorrectly.  This is a hardware bug, and
 665          * we don't have a good way to deal with it.  The 2s window stuff
 666          * (below) is our best option for now.
 667          */
 668         if (psmouse_activate(psmouse))
 669                 return -1;
 670
 671         if (tpdebug)
 672                 psmouse_dbg(psmouse, "touchpad reactivated\n");
 673
 674         /*
 675          * If we get packets right away after recalibrating, it's likely
 676          * that a finger was on the touchpad.  If so, it's probably
 677          * miscalibrated, so we optionally schedule another.
 678          */
 679         if (recal_guard_time)
 680                 priv->recalib_window = jiffies +
 681                         msecs_to_jiffies(recal_guard_time);
 682
 683         return 0;
 684 }
 685
 686 /*
 687  * This puts the touchpad in a power saving mode; according to ALPS, current
 688  * consumption goes down to 50uA after running this.  To turn power back on,
 689  * we drive MS-DAT low.  Measuring with a 1mA resolution ammeter says that
 690  * the current on the SUS_3.3V rail drops from 3mA or 4mA to 0 when we do this.
 691  *
 692  * We have no formal spec that details this operation -- the low-power
 693  * sequence came from a long-lost email trail.
 694  */
 695 static int hgpk_toggle_powersave(struct psmouse *psmouse, int enable)
 696 {
 697         struct ps2dev *ps2dev = &psmouse->ps2dev;
 698         int timeo;
 699         int err;
 700
 701         /* Added on D-series touchpads */
 702         if (psmouse->model < HGPK_MODEL_D)
 703                 return 0;
 704
 705         if (enable) {
 706                 psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 707
 708                 /*
 709                  * Sending a byte will drive MS-DAT low; this will wake up
 710                  * the controller.  Once we get an ACK back from it, it
 711                  * means we can continue with the touchpad re-init.  ALPS
 712                  * tells us that 1s should be long enough, so set that as
 713                  * the upper bound. (in practice, it takes about 3 loops.)
 714                  */
 715                 for (timeo = 20; timeo > 0; timeo--) {
 716                         if (!ps2_sendbyte(&psmouse->ps2dev,
 717                                         PSMOUSE_CMD_DISABLE, 20))
 718                                 break;
 719                         msleep(25);
 720                 }
 721
 722                 err = hgpk_reset_device(psmouse, false);
 723                 if (err) {
 724                         psmouse_err(psmouse, "Failed to reset device!\n");
 725                         return err;
 726                 }
 727
 728                 /* should be all set, enable the touchpad */
 729                 psmouse_activate(psmouse);
 730                 psmouse_dbg(psmouse, "Touchpad powered up.\n");
 731         } else {
 732                 psmouse_dbg(psmouse, "Powering off touchpad.\n");
 733
 734                 if (ps2_command(ps2dev, NULL, 0xec) ||
 735                     ps2_command(ps2dev, NULL, 0xec) ||
 736                     ps2_command(ps2dev, NULL, 0xea)) {
 737                         return -1;
 738                 }
 739
 740                 psmouse_set_state(psmouse, PSMOUSE_IGNORE);
 741
 742                 /* probably won't see an ACK, the touchpad will be off */
 743                 ps2_sendbyte(&psmouse->ps2dev, 0xec, 20);
 744         }
 745
 746         return 0;
 747 }
 748
 749 static int hgpk_poll(struct psmouse *psmouse)
 750 {
 751         /* We can't poll, so always return failure. */
 752         return -1;
 753 }
 754
 755 static int hgpk_reconnect(struct psmouse *psmouse)
 756 {
 757         struct hgpk_data *priv = psmouse->private;
 758
 759         /*
 760          * During suspend/resume the ps2 rails remain powered.  We don't want
 761          * to do a reset because it's flush data out of buffers; however,
 762          * earlier prototypes (B1) had some brokenness that required a reset.
 763          */
 764         if (olpc_board_at_least(olpc_board(0xb2)))
 765                 if (psmouse->ps2dev.serio->dev.power.power_state.event !=
 766                                 PM_EVENT_ON)
 767                         return 0;
 768
 769         priv->powered = 1;
 770         return hgpk_reset_device(psmouse, false);
 771 }
 772
 773 static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char *buf)
 774 {
 775         struct hgpk_data *priv = psmouse->private;
 776
 777         return sprintf(buf, "%d\n", priv->powered);
 778 }
 779
 780 static ssize_t hgpk_set_powered(struct psmouse *psmouse, void *data,
 781                                 const char *buf, size_t count)
 782 {
 783         struct hgpk_data *priv = psmouse->private;
 784         unsigned int value;
 785         int err;
 786
 787         err = kstrtouint(buf, 10, &value);
 788         if (err)
 789                 return err;
 790
 791         if (value > 1)
 792                 return -EINVAL;
 793
 794         if (value != priv->powered) {
 795                 /*
 796                  * hgpk_toggle_power will deal w/ state so
 797                  * we're not racing w/ irq
 798                  */
 799                 err = hgpk_toggle_powersave(psmouse, value);
 800                 if (!err)
 801                         priv->powered = value;
 802         }
 803
 804         return err ? err : count;
 805 }
 806
 807 __PSMOUSE_DEFINE_ATTR(powered, S_IWUSR | S_IRUGO, NULL,
 808                       hgpk_show_powered, hgpk_set_powered, false);
 809
 810 static ssize_t attr_show_mode(struct psmouse *psmouse, void *data, char *buf)
 811 {
 812         struct hgpk_data *priv = psmouse->private;
 813
 814         return sprintf(buf, "%s\n", hgpk_mode_names[priv->mode]);
 815 }
 816
 817 static ssize_t attr_set_mode(struct psmouse *psmouse, void *data,
 818                              const char *buf, size_t len)
 819 {
 820         struct hgpk_data *priv = psmouse->private;
 821         enum hgpk_mode old_mode = priv->mode;
 822         enum hgpk_mode new_mode = hgpk_mode_from_name(buf, len);
 823         struct input_dev *old_dev = psmouse->dev;
 824         struct input_dev *new_dev;
 825         int err;
 826
 827         if (new_mode == HGPK_MODE_INVALID)
 828                 return -EINVAL;
 829
 830         if (old_mode == new_mode)
 831                 return len;
 832
 833         new_dev = input_allocate_device();
 834         if (!new_dev)
 835                 return -ENOMEM;
 836
 837         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 838
 839         /* Switch device into the new mode */
 840         priv->mode = new_mode;
 841         err = hgpk_reset_device(psmouse, false);
 842         if (err)
 843                 goto err_try_restore;
 844
 845         hgpk_setup_input_device(new_dev, old_dev, new_mode);
 846
 847         psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
 848
 849         err = input_register_device(new_dev);
 850         if (err)
 851                 goto err_try_restore;
 852
 853         psmouse->dev = new_dev;
 854         input_unregister_device(old_dev);
 855
 856         return len;
 857
 858 err_try_restore:
 859         input_free_device(new_dev);
 860         priv->mode = old_mode;
 861         hgpk_reset_device(psmouse, false);
 862
 863         return err;
 864 }
 865
 866 PSMOUSE_DEFINE_ATTR(hgpk_mode, S_IWUSR | S_IRUGO, NULL,
 867                     attr_show_mode, attr_set_mode);
 868
 869 static ssize_t hgpk_trigger_recal_show(struct psmouse *psmouse,
 870                 void *data, char *buf)
 871 {
 872         return -EINVAL;
 873 }
 874
 875 static ssize_t hgpk_trigger_recal(struct psmouse *psmouse, void *data,
 876                                 const char *buf, size_t count)
 877 {
 878         struct hgpk_data *priv = psmouse->private;
 879         unsigned int value;
 880         int err;
 881
 882         err = kstrtouint(buf, 10, &value);
 883         if (err)
 884                 return err;
 885
 886         if (value != 1)
 887                 return -EINVAL;
 888
 889         /*
 890          * We queue work instead of doing recalibration right here
 891          * to avoid adding locking to to hgpk_force_recalibrate()
 892          * since workqueue provides serialization.
 893          */
 894         psmouse_queue_work(psmouse, &priv->recalib_wq, 0);
 895         return count;
 896 }
 897
 898 __PSMOUSE_DEFINE_ATTR(recalibrate, S_IWUSR | S_IRUGO, NULL,
 899                       hgpk_trigger_recal_show, hgpk_trigger_recal, false);
 900
 901 static void hgpk_disconnect(struct psmouse *psmouse)
 902 {
 903         struct hgpk_data *priv = psmouse->private;
 904
 905         device_remove_file(&psmouse->ps2dev.serio->dev,
 906                            &psmouse_attr_powered.dattr);
 907         device_remove_file(&psmouse->ps2dev.serio->dev,
 908                            &psmouse_attr_hgpk_mode.dattr);
 909
 910         if (psmouse->model >= HGPK_MODEL_C)
 911                 device_remove_file(&psmouse->ps2dev.serio->dev,
 912                                    &psmouse_attr_recalibrate.dattr);
 913
 914         psmouse_reset(psmouse);
 915         kfree(priv);
 916 }
 917
 918 static void hgpk_recalib_work(struct work_struct *work)
 919 {
 920         struct delayed_work *w = to_delayed_work(work);
 921         struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq);
 922         struct psmouse *psmouse = priv->psmouse;
 923
 924         if (hgpk_force_recalibrate(psmouse))
 925                 psmouse_err(psmouse, "recalibration failed!\n");
 926 }
 927
 928 static int hgpk_register(struct psmouse *psmouse)
 929 {
 930         struct hgpk_data *priv = psmouse->private;
 931         int err;
 932
 933         /* register handlers */
 934         psmouse->protocol_handler = hgpk_process_byte;
 935         psmouse->poll = hgpk_poll;
 936         psmouse->disconnect = hgpk_disconnect;
 937         psmouse->reconnect = hgpk_reconnect;
 938
 939         /* Disable the idle resync. */
 940         psmouse->resync_time = 0;
 941         /* Reset after a lot of bad bytes. */
 942         psmouse->resetafter = 1024;
 943
 944         hgpk_setup_input_device(psmouse->dev, NULL, priv->mode);
 945
 946         err = device_create_file(&psmouse->ps2dev.serio->dev,
 947                                  &psmouse_attr_powered.dattr);
 948         if (err) {
 949                 psmouse_err(psmouse, "Failed creating 'powered' sysfs node\n");
 950                 return err;
 951         }
 952
 953         err = device_create_file(&psmouse->ps2dev.serio->dev,
 954                                  &psmouse_attr_hgpk_mode.dattr);
 955         if (err) {
 956                 psmouse_err(psmouse,
 957                             "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                         psmouse_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         psmouse_dbg(psmouse, "ID: %*ph\n", 3, param);
1031
1032         /* HGPK signature: 0x67, 0x00, 0x<model> */
1033         if (param[0] != 0x67 || param[1] != 0x00)
1034                 return -ENODEV;
1035
1036         psmouse_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 }