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