drivers/input/mouse/hgpk.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * OLPC HGPK (XO-1) touchpad PS/2 mouse driver
   4  *
   5  * Copyright (c) 2006-2008 One Laptop Per Child
   6  * Authors:
   7  *   Zephaniah E. Hull
   8  *   Andres Salomon <dilinger@debian.org>
   9  *
  10  * This driver is partly based on the ALPS driver, which is:
  11  *
  12  * Copyright (c) 2003 Neil Brown <neilb@cse.unsw.edu.au>
  13  * Copyright (c) 2003-2005 Peter Osterlund <petero2@telia.com>
  14  * Copyright (c) 2004 Dmitry Torokhov <dtor@mail.ru>
  15  * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
  16  */
  17
  18 /*
  19  * The spec from ALPS is available from
  20  * <http://wiki.laptop.org/go/Touch_Pad/Tablet>.  It refers to this
  21  * device as HGPK (Hybrid GS, PT, and Keymatrix).
  22  *
  23  * The earliest versions of the device had simultaneous reporting; that
  24  * was removed.  After that, the device used the Advanced Mode GS/PT streaming
  25  * stuff.  That turned out to be too buggy to support, so we've finally
  26  * switched to Mouse Mode (which utilizes only the center 1/3 of the touchpad).
  27  */
  28
  29 #define DEBUG
  30 #include <linux/slab.h>
  31 #include <linux/input.h>
  32 #include <linux/module.h>
  33 #include <linux/serio.h>
  34 #include <linux/libps2.h>
  35 #include <linux/delay.h>
  36 #include <asm/olpc.h>
  37
  38 #include "psmouse.h"
  39 #include "hgpk.h"
  40
  41 #define ILLEGAL_XY 999999
  42
  43 static bool tpdebug;
  44 module_param(tpdebug, bool, 0644);
  45 MODULE_PARM_DESC(tpdebug, "enable debugging, dumping packets to KERN_DEBUG.");
  46
  47 static int recalib_delta = 100;
  48 module_param(recalib_delta, int, 0644);
  49 MODULE_PARM_DESC(recalib_delta,
  50         "packets containing a delta this large will be discarded, and a "
  51         "recalibration may be scheduled.");
  52
  53 static int jumpy_delay = 20;
  54 module_param(jumpy_delay, int, 0644);
  55 MODULE_PARM_DESC(jumpy_delay,
  56         "delay (ms) before recal after jumpiness detected");
  57
  58 static int spew_delay = 1;
  59 module_param(spew_delay, int, 0644);
  60 MODULE_PARM_DESC(spew_delay,
  61         "delay (ms) before recal after packet spew detected");
  62
  63 static int recal_guard_time;
  64 module_param(recal_guard_time, int, 0644);
  65 MODULE_PARM_DESC(recal_guard_time,
  66         "interval (ms) during which recal will be restarted if packet received");
  67
  68 static int post_interrupt_delay = 40;
  69 module_param(post_interrupt_delay, int, 0644);
  70 MODULE_PARM_DESC(post_interrupt_delay,
  71         "delay (ms) before recal after recal interrupt detected");
  72
  73 static bool autorecal = true;
  74 module_param(autorecal, bool, 0644);
  75 MODULE_PARM_DESC(autorecal, "enable recalibration in the driver");
  76
  77 static char hgpk_mode_name[16];
  78 module_param_string(hgpk_mode, hgpk_mode_name, sizeof(hgpk_mode_name), 0644);
  79 MODULE_PARM_DESC(hgpk_mode,
  80         "default hgpk mode: mouse, glidesensor or pentablet");
  81
  82 static int hgpk_default_mode = HGPK_MODE_MOUSE;
  83
  84 static const char * const hgpk_mode_names[] = {
  85         [HGPK_MODE_MOUSE] = "Mouse",
  86         [HGPK_MODE_GLIDESENSOR] = "GlideSensor",
  87         [HGPK_MODE_PENTABLET] = "PenTablet",
  88 };
  89
  90 static int hgpk_mode_from_name(const char *buf, int len)
  91 {
  92         int i;
  93
  94         for (i = 0; i < ARRAY_SIZE(hgpk_mode_names); i++) {
  95                 const char *name = hgpk_mode_names[i];
  96                 if (strlen(name) == len && !strncasecmp(name, buf, len))
  97                         return i;
  98         }
  99
 100         return HGPK_MODE_INVALID;
 101 }
 102
 103 /*
 104  * see if new value is within 20% of half of old value
 105  */
 106 static int approx_half(int curr, int prev)
 107 {
 108         int belowhalf, abovehalf;
 109
 110         if (curr < 5 || prev < 5)
 111                 return 0;
 112
 113         belowhalf = (prev * 8) / 20;
 114         abovehalf = (prev * 12) / 20;
 115
 116         return belowhalf < curr && curr <= abovehalf;
 117 }
 118
 119 /*
 120  * Throw out oddly large delta packets, and any that immediately follow whose
 121  * values are each approximately half of the previous.  It seems that the ALPS
 122  * firmware emits errant packets, and they get averaged out slowly.
 123  */
 124 static int hgpk_discard_decay_hack(struct psmouse *psmouse, int x, int y)
 125 {
 126         struct hgpk_data *priv = psmouse->private;
 127         int avx, avy;
 128         bool do_recal = false;
 129
 130         avx = abs(x);
 131         avy = abs(y);
 132
 133         /* discard if too big, or half that but > 4 times the prev delta */
 134         if (avx > recalib_delta ||
 135                 (avx > recalib_delta / 2 && ((avx / 4) > priv->xlast))) {
 136                 psmouse_warn(psmouse, "detected %dpx jump in x\n", x);
 137                 priv->xbigj = avx;
 138         } else if (approx_half(avx, priv->xbigj)) {
 139                 psmouse_warn(psmouse, "detected secondary %dpx jump in x\n", x);
 140                 priv->xbigj = avx;
 141                 priv->xsaw_secondary++;
 142         } else {
 143                 if (priv->xbigj && priv->xsaw_secondary > 1)
 144                         do_recal = true;
 145                 priv->xbigj = 0;
 146                 priv->xsaw_secondary = 0;
 147         }
 148
 149         if (avy > recalib_delta ||
 150                 (avy > recalib_delta / 2 && ((avy / 4) > priv->ylast))) {
 151                 psmouse_warn(psmouse, "detected %dpx jump in y\n", y);
 152                 priv->ybigj = avy;
 153         } else if (approx_half(avy, priv->ybigj)) {
 154                 psmouse_warn(psmouse, "detected secondary %dpx jump in y\n", y);
 155                 priv->ybigj = avy;
 156                 priv->ysaw_secondary++;
 157         } else {
 158                 if (priv->ybigj && priv->ysaw_secondary > 1)
 159                         do_recal = true;
 160                 priv->ybigj = 0;
 161                 priv->ysaw_secondary = 0;
 162         }
 163
 164         priv->xlast = avx;
 165         priv->ylast = avy;
 166
 167         if (do_recal && jumpy_delay) {
 168                 psmouse_warn(psmouse, "scheduling recalibration\n");
 169                 psmouse_queue_work(psmouse, &priv->recalib_wq,
 170                                 msecs_to_jiffies(jumpy_delay));
 171         }
 172
 173         return priv->xbigj || priv->ybigj;
 174 }
 175
 176 static void hgpk_reset_spew_detection(struct hgpk_data *priv)
 177 {
 178         priv->spew_count = 0;
 179         priv->dupe_count = 0;
 180         priv->x_tally = 0;
 181         priv->y_tally = 0;
 182         priv->spew_flag = NO_SPEW;
 183 }
 184
 185 static void hgpk_reset_hack_state(struct psmouse *psmouse)
 186 {
 187         struct hgpk_data *priv = psmouse->private;
 188
 189         priv->abs_x = priv->abs_y = -1;
 190         priv->xlast = priv->ylast = ILLEGAL_XY;
 191         priv->xbigj = priv->ybigj = 0;
 192         priv->xsaw_secondary = priv->ysaw_secondary = 0;
 193         hgpk_reset_spew_detection(priv);
 194 }
 195
 196 /*
 197  * We have no idea why this particular hardware bug occurs.  The touchpad
 198  * will randomly start spewing packets without anything touching the
 199  * pad.  This wouldn't necessarily be bad, but it's indicative of a
 200  * severely miscalibrated pad; attempting to use the touchpad while it's
 201  * spewing means the cursor will jump all over the place, and act "drunk".
 202  *
 203  * The packets that are spewed tend to all have deltas between -2 and 2, and
 204  * the cursor will move around without really going very far.  It will
 205  * tend to end up in the same location; if we tally up the changes over
 206  * 100 packets, we end up w/ a final delta of close to 0.  This happens
 207  * pretty regularly when the touchpad is spewing, and is pretty hard to
 208  * manually trigger (at least for *my* fingers).  So, it makes a perfect
 209  * scheme for detecting spews.
 210  */
 211 static void hgpk_spewing_hack(struct psmouse *psmouse,
 212                               int l, int r, int x, int y)
 213 {
 214         struct hgpk_data *priv = psmouse->private;
 215
 216         /* ignore button press packets; many in a row could trigger
 217          * a false-positive! */
 218         if (l || r)
 219                 return;
 220
 221         /* don't track spew if the workaround feature has been turned off */
 222         if (!spew_delay)
 223                 return;
 224
 225         if (abs(x) > 3 || abs(y) > 3) {
 226                 /* no spew, or spew ended */
 227                 hgpk_reset_spew_detection(priv);
 228                 return;
 229         }
 230
 231         /* Keep a tally of the overall delta to the cursor position caused by
 232          * the spew */
 233         priv->x_tally += x;
 234         priv->y_tally += y;
 235
 236         switch (priv->spew_flag) {
 237         case NO_SPEW:
 238                 /* we're not spewing, but this packet might be the start */
 239                 priv->spew_flag = MAYBE_SPEWING;
 240
 241                 fallthrough;
 242
 243         case MAYBE_SPEWING:
 244                 priv->spew_count++;
 245
 246                 if (priv->spew_count < SPEW_WATCH_COUNT)
 247                         break;
 248
 249                 /* excessive spew detected, request recalibration */
 250                 priv->spew_flag = SPEW_DETECTED;
 251
 252                 fallthrough;
 253
 254         case SPEW_DETECTED:
 255                 /* only recalibrate when the overall delta to the cursor
 256                  * is really small. if the spew is causing significant cursor
 257                  * movement, it is probably a case of the user moving the
 258                  * cursor very slowly across the screen. */
 259                 if (abs(priv->x_tally) < 3 && abs(priv->y_tally) < 3) {
 260                         psmouse_warn(psmouse, "packet spew detected (%d,%d)\n",
 261                                      priv->x_tally, priv->y_tally);
 262                         priv->spew_flag = RECALIBRATING;
 263                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 264                                            msecs_to_jiffies(spew_delay));
 265                 }
 266
 267                 break;
 268         case RECALIBRATING:
 269                 /* we already detected a spew and requested a recalibration,
 270                  * just wait for the queue to kick into action. */
 271                 break;
 272         }
 273 }
 274
 275 /*
 276  * HGPK Mouse Mode format (standard mouse format, sans middle button)
 277  *
 278  * byte 0:      y-over  x-over  y-neg   x-neg   1       0       swr     swl
 279  * byte 1:      x7      x6      x5      x4      x3      x2      x1      x0
 280  * byte 2:      y7      y6      y5      y4      y3      y2      y1      y0
 281  *
 282  * swr/swl are the left/right buttons.
 283  * x-neg/y-neg are the x and y delta negative bits
 284  * x-over/y-over are the x and y overflow bits
 285  *
 286  * ---
 287  *
 288  * HGPK Advanced Mode - single-mode format
 289  *
 290  * byte 0(PT):  1    1    0    0    1    1     1     1
 291  * byte 0(GS):  1    1    1    1    1    1     1     1
 292  * byte 1:      0   x6   x5   x4   x3   x2    x1    x0
 293  * byte 2(PT):  0    0   x9   x8   x7    ? pt-dsw    0
 294  * byte 2(GS):  0  x10   x9   x8   x7    ? gs-dsw pt-dsw
 295  * byte 3:      0   y9   y8   y7    1    0   swr   swl
 296  * byte 4:      0   y6   y5   y4   y3   y2    y1    y0
 297  * byte 5:      0   z6   z5   z4   z3   z2    z1    z0
 298  *
 299  * ?'s are not defined in the protocol spec, may vary between models.
 300  *
 301  * swr/swl are the left/right buttons.
 302  *
 303  * pt-dsw/gs-dsw indicate that the pt/gs sensor is detecting a
 304  * pen/finger
 305  */
 306 static bool hgpk_is_byte_valid(struct psmouse *psmouse, unsigned char *packet)
 307 {
 308         struct hgpk_data *priv = psmouse->private;
 309         int pktcnt = psmouse->pktcnt;
 310         bool valid;
 311
 312         switch (priv->mode) {
 313         case HGPK_MODE_MOUSE:
 314                 valid = (packet[0] & 0x0C) == 0x08;
 315                 break;
 316
 317         case HGPK_MODE_GLIDESENSOR:
 318                 valid = pktcnt == 1 ?
 319                         packet[0] == HGPK_GS : !(packet[pktcnt - 1] & 0x80);
 320                 break;
 321
 322         case HGPK_MODE_PENTABLET:
 323                 valid = pktcnt == 1 ?
 324                         packet[0] == HGPK_PT : !(packet[pktcnt - 1] & 0x80);
 325                 break;
 326
 327         default:
 328                 valid = false;
 329                 break;
 330         }
 331
 332         if (!valid)
 333                 psmouse_dbg(psmouse,
 334                             "bad data, mode %d (%d) %*ph\n",
 335                             priv->mode, pktcnt, 6, psmouse->packet);
 336
 337         return valid;
 338 }
 339
 340 static void hgpk_process_advanced_packet(struct psmouse *psmouse)
 341 {
 342         struct hgpk_data *priv = psmouse->private;
 343         struct input_dev *idev = psmouse->dev;
 344         unsigned char *packet = psmouse->packet;
 345         int down = !!(packet[2] & 2);
 346         int left = !!(packet[3] & 1);
 347         int right = !!(packet[3] & 2);
 348         int x = packet[1] | ((packet[2] & 0x78) << 4);
 349         int y = packet[4] | ((packet[3] & 0x70) << 3);
 350
 351         if (priv->mode == HGPK_MODE_GLIDESENSOR) {
 352                 int pt_down = !!(packet[2] & 1);
 353                 int finger_down = !!(packet[2] & 2);
 354                 int z = packet[5];
 355
 356                 input_report_abs(idev, ABS_PRESSURE, z);
 357                 if (tpdebug)
 358                         psmouse_dbg(psmouse, "pd=%d fd=%d z=%d",
 359                                     pt_down, finger_down, z);
 360         } else {
 361                 /*
 362                  * PenTablet mode does not report pressure, so we don't
 363                  * report it here
 364                  */
 365                 if (tpdebug)
 366                         psmouse_dbg(psmouse, "pd=%d ", down);
 367         }
 368
 369         if (tpdebug)
 370                 psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
 371                             left, right, x, y);
 372
 373         input_report_key(idev, BTN_TOUCH, down);
 374         input_report_key(idev, BTN_LEFT, left);
 375         input_report_key(idev, BTN_RIGHT, right);
 376
 377         /*
 378          * If this packet says that the finger was removed, reset our position
 379          * tracking so that we don't erroneously detect a jump on next press.
 380          */
 381         if (!down) {
 382                 hgpk_reset_hack_state(psmouse);
 383                 goto done;
 384         }
 385
 386         /*
 387          * Weed out duplicate packets (we get quite a few, and they mess up
 388          * our jump detection)
 389          */
 390         if (x == priv->abs_x && y == priv->abs_y) {
 391                 if (++priv->dupe_count > SPEW_WATCH_COUNT) {
 392                         if (tpdebug)
 393                                 psmouse_dbg(psmouse, "hard spew detected\n");
 394                         priv->spew_flag = RECALIBRATING;
 395                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 396                                            msecs_to_jiffies(spew_delay));
 397                 }
 398                 goto done;
 399         }
 400
 401         /* not a duplicate, continue with position reporting */
 402         priv->dupe_count = 0;
 403
 404         /* Don't apply hacks in PT mode, it seems reliable */
 405         if (priv->mode != HGPK_MODE_PENTABLET && priv->abs_x != -1) {
 406                 int x_diff = priv->abs_x - x;
 407                 int y_diff = priv->abs_y - y;
 408                 if (hgpk_discard_decay_hack(psmouse, x_diff, y_diff)) {
 409                         if (tpdebug)
 410                                 psmouse_dbg(psmouse, "discarding\n");
 411                         goto done;
 412                 }
 413                 hgpk_spewing_hack(psmouse, left, right, x_diff, y_diff);
 414         }
 415
 416         input_report_abs(idev, ABS_X, x);
 417         input_report_abs(idev, ABS_Y, y);
 418         priv->abs_x = x;
 419         priv->abs_y = y;
 420
 421 done:
 422         input_sync(idev);
 423 }
 424
 425 static void hgpk_process_simple_packet(struct psmouse *psmouse)
 426 {
 427         struct input_dev *dev = psmouse->dev;
 428         unsigned char *packet = psmouse->packet;
 429         int left = packet[0] & 1;
 430         int right = (packet[0] >> 1) & 1;
 431         int x = packet[1] - ((packet[0] << 4) & 0x100);
 432         int y = ((packet[0] << 3) & 0x100) - packet[2];
 433
 434         if (packet[0] & 0xc0)
 435                 psmouse_dbg(psmouse,
 436                             "overflow -- 0x%02x 0x%02x 0x%02x\n",
 437                             packet[0], packet[1], packet[2]);
 438
 439         if (hgpk_discard_decay_hack(psmouse, x, y)) {
 440                 if (tpdebug)
 441                         psmouse_dbg(psmouse, "discarding\n");
 442                 return;
 443         }
 444
 445         hgpk_spewing_hack(psmouse, left, right, x, y);
 446
 447         if (tpdebug)
 448                 psmouse_dbg(psmouse, "l=%d r=%d x=%d y=%d\n",
 449                             left, right, x, y);
 450
 451         input_report_key(dev, BTN_LEFT, left);
 452         input_report_key(dev, BTN_RIGHT, right);
 453
 454         input_report_rel(dev, REL_X, x);
 455         input_report_rel(dev, REL_Y, y);
 456
 457         input_sync(dev);
 458 }
 459
 460 static psmouse_ret_t hgpk_process_byte(struct psmouse *psmouse)
 461 {
 462         struct hgpk_data *priv = psmouse->private;
 463
 464         if (!hgpk_is_byte_valid(psmouse, psmouse->packet))
 465                 return PSMOUSE_BAD_DATA;
 466
 467         if (psmouse->pktcnt >= psmouse->pktsize) {
 468                 if (priv->mode == HGPK_MODE_MOUSE)
 469                         hgpk_process_simple_packet(psmouse);
 470                 else
 471                         hgpk_process_advanced_packet(psmouse);
 472                 return PSMOUSE_FULL_PACKET;
 473         }
 474
 475         if (priv->recalib_window) {
 476                 if (time_before(jiffies, priv->recalib_window)) {
 477                         /*
 478                          * ugh, got a packet inside our recalibration
 479                          * window, schedule another recalibration.
 480                          */
 481                         psmouse_dbg(psmouse,
 482                                     "packet inside calibration window, queueing another recalibration\n");
 483                         psmouse_queue_work(psmouse, &priv->recalib_wq,
 484                                         msecs_to_jiffies(post_interrupt_delay));
 485                 }
 486                 priv->recalib_window = 0;
 487         }
 488
 489         return PSMOUSE_GOOD_DATA;
 490 }
 491
 492 static int hgpk_select_mode(struct psmouse *psmouse)
 493 {
 494         struct ps2dev *ps2dev = &psmouse->ps2dev;
 495         struct hgpk_data *priv = psmouse->private;
 496         int i;
 497         int cmd;
 498
 499         /*
 500          * 4 disables to enable advanced mode
 501          * then 3 0xf2 bytes as the preamble for GS/PT selection
 502          */
 503         const int advanced_init[] = {
 504                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 505                 PSMOUSE_CMD_DISABLE, PSMOUSE_CMD_DISABLE,
 506                 0xf2, 0xf2, 0xf2,
 507         };
 508
 509         switch (priv->mode) {
 510         case HGPK_MODE_MOUSE:
 511                 psmouse->pktsize = 3;
 512                 break;
 513
 514         case HGPK_MODE_GLIDESENSOR:
 515         case HGPK_MODE_PENTABLET:
 516                 psmouse->pktsize = 6;
 517
 518                 /* Switch to 'Advanced mode.', four disables in a row. */
 519                 for (i = 0; i < ARRAY_SIZE(advanced_init); i++)
 520                         if (ps2_command(ps2dev, NULL, advanced_init[i]))
 521                                 return -EIO;
 522
 523                 /* select between GlideSensor (mouse) or PenTablet */
 524                 cmd = priv->mode == HGPK_MODE_GLIDESENSOR ?
 525                         PSMOUSE_CMD_SETSCALE11 : PSMOUSE_CMD_SETSCALE21;
 526
 527                 if (ps2_command(ps2dev, NULL, cmd))
 528                         return -EIO;
 529                 break;
 530
 531         default:
 532                 return -EINVAL;
 533         }
 534
 535         return 0;
 536 }
 537
 538 static void hgpk_setup_input_device(struct input_dev *input,
 539                                     struct input_dev *old_input,
 540                                     enum hgpk_mode mode)
 541 {
 542         if (old_input) {
 543                 input->name = old_input->name;
 544                 input->phys = old_input->phys;
 545                 input->id = old_input->id;
 546                 input->dev.parent = old_input->dev.parent;
 547         }
 548
 549         memset(input->evbit, 0, sizeof(input->evbit));
 550         memset(input->relbit, 0, sizeof(input->relbit));
 551         memset(input->keybit, 0, sizeof(input->keybit));
 552
 553         /* All modes report left and right buttons */
 554         __set_bit(EV_KEY, input->evbit);
 555         __set_bit(BTN_LEFT, input->keybit);
 556         __set_bit(BTN_RIGHT, input->keybit);
 557
 558         switch (mode) {
 559         case HGPK_MODE_MOUSE:
 560                 __set_bit(EV_REL, input->evbit);
 561                 __set_bit(REL_X, input->relbit);
 562                 __set_bit(REL_Y, input->relbit);
 563                 break;
 564
 565         case HGPK_MODE_GLIDESENSOR:
 566                 __set_bit(BTN_TOUCH, input->keybit);
 567                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 568
 569                 __set_bit(EV_ABS, input->evbit);
 570
 571                 /* GlideSensor has pressure sensor, PenTablet does not */
 572                 input_set_abs_params(input, ABS_PRESSURE, 0, 15, 0, 0);
 573
 574                 /* From device specs */
 575                 input_set_abs_params(input, ABS_X, 0, 399, 0, 0);
 576                 input_set_abs_params(input, ABS_Y, 0, 290, 0, 0);
 577
 578                 /* Calculated by hand based on usable size (52mm x 38mm) */
 579                 input_abs_set_res(input, ABS_X, 8);
 580                 input_abs_set_res(input, ABS_Y, 8);
 581                 break;
 582
 583         case HGPK_MODE_PENTABLET:
 584                 __set_bit(BTN_TOUCH, input->keybit);
 585                 __set_bit(BTN_TOOL_FINGER, input->keybit);
 586
 587                 __set_bit(EV_ABS, input->evbit);
 588
 589                 /* From device specs */
 590                 input_set_abs_params(input, ABS_X, 0, 999, 0, 0);
 591                 input_set_abs_params(input, ABS_Y, 5, 239, 0, 0);
 592
 593                 /* Calculated by hand based on usable size (156mm x 38mm) */
 594                 input_abs_set_res(input, ABS_X, 6);
 595                 input_abs_set_res(input, ABS_Y, 8);
 596                 break;
 597
 598         default:
 599                 BUG();
 600         }
 601 }
 602
 603 static int hgpk_reset_device(struct psmouse *psmouse, bool recalibrate)
 604 {
 605         int err;
 606
 607         psmouse_reset(psmouse);
 608
 609         if (recalibrate) {
 610                 struct ps2dev *ps2dev = &psmouse->ps2dev;
 611
 612                 /* send the recalibrate request */
 613                 if (ps2_command(ps2dev, NULL, 0xf5) ||
 614                     ps2_command(ps2dev, NULL, 0xf5) ||
 615                     ps2_command(ps2dev, NULL, 0xe6) ||
 616                     ps2_command(ps2dev, NULL, 0xf5)) {
 617                         return -1;
 618                 }
 619
 620                 /* according to ALPS, 150mS is required for recalibration */
 621                 msleep(150);
 622         }
 623
 624         err = hgpk_select_mode(psmouse);
 625         if (err) {
 626                 psmouse_err(psmouse, "failed to select mode\n");
 627                 return err;
 628         }
 629
 630         hgpk_reset_hack_state(psmouse);
 631
 632         return 0;
 633 }
 634
 635 static int hgpk_force_recalibrate(struct psmouse *psmouse)
 636 {
 637         struct hgpk_data *priv = psmouse->private;
 638         int err;
 639
 640         /* C-series touchpads added the recalibrate command */
 641         if (psmouse->model < HGPK_MODEL_C)
 642                 return 0;
 643
 644         if (!autorecal) {
 645                 psmouse_dbg(psmouse, "recalibration disabled, ignoring\n");
 646                 return 0;
 647         }
 648
 649         psmouse_dbg(psmouse, "recalibrating touchpad..\n");
 650
 651         /* we don't want to race with the irq handler, nor with resyncs */
 652         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 653
 654         /* start by resetting the device */
 655         err = hgpk_reset_device(psmouse, true);
 656         if (err)
 657                 return err;
 658
 659         /*
 660          * XXX: If a finger is down during this delay, recalibration will
 661          * detect capacitance incorrectly.  This is a hardware bug, and
 662          * we don't have a good way to deal with it.  The 2s window stuff
 663          * (below) is our best option for now.
 664          */
 665         if (psmouse_activate(psmouse))
 666                 return -1;
 667
 668         if (tpdebug)
 669                 psmouse_dbg(psmouse, "touchpad reactivated\n");
 670
 671         /*
 672          * If we get packets right away after recalibrating, it's likely
 673          * that a finger was on the touchpad.  If so, it's probably
 674          * miscalibrated, so we optionally schedule another.
 675          */
 676         if (recal_guard_time)
 677                 priv->recalib_window = jiffies +
 678                         msecs_to_jiffies(recal_guard_time);
 679
 680         return 0;
 681 }
 682
 683 /*
 684  * This puts the touchpad in a power saving mode; according to ALPS, current
 685  * consumption goes down to 50uA after running this.  To turn power back on,
 686  * we drive MS-DAT low.  Measuring with a 1mA resolution ammeter says that
 687  * the current on the SUS_3.3V rail drops from 3mA or 4mA to 0 when we do this.
 688  *
 689  * We have no formal spec that details this operation -- the low-power
 690  * sequence came from a long-lost email trail.
 691  */
 692 static int hgpk_toggle_powersave(struct psmouse *psmouse, int enable)
 693 {
 694         struct ps2dev *ps2dev = &psmouse->ps2dev;
 695         int timeo;
 696         int err;
 697
 698         /* Added on D-series touchpads */
 699         if (psmouse->model < HGPK_MODEL_D)
 700                 return 0;
 701
 702         if (enable) {
 703                 psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 704
 705                 /*
 706                  * Sending a byte will drive MS-DAT low; this will wake up
 707                  * the controller.  Once we get an ACK back from it, it
 708                  * means we can continue with the touchpad re-init.  ALPS
 709                  * tells us that 1s should be long enough, so set that as
 710                  * the upper bound. (in practice, it takes about 3 loops.)
 711                  */
 712                 for (timeo = 20; timeo > 0; timeo--) {
 713                         if (!ps2_sendbyte(ps2dev, PSMOUSE_CMD_DISABLE, 20))
 714                                 break;
 715                         msleep(25);
 716                 }
 717
 718                 err = hgpk_reset_device(psmouse, false);
 719                 if (err) {
 720                         psmouse_err(psmouse, "Failed to reset device!\n");
 721                         return err;
 722                 }
 723
 724                 /* should be all set, enable the touchpad */
 725                 psmouse_activate(psmouse);
 726                 psmouse_dbg(psmouse, "Touchpad powered up.\n");
 727         } else {
 728                 psmouse_dbg(psmouse, "Powering off touchpad.\n");
 729
 730                 if (ps2_command(ps2dev, NULL, 0xec) ||
 731                     ps2_command(ps2dev, NULL, 0xec) ||
 732                     ps2_command(ps2dev, NULL, 0xea)) {
 733                         return -1;
 734                 }
 735
 736                 psmouse_set_state(psmouse, PSMOUSE_IGNORE);
 737
 738                 /* probably won't see an ACK, the touchpad will be off */
 739                 ps2_sendbyte(ps2dev, 0xec, 20);
 740         }
 741
 742         return 0;
 743 }
 744
 745 static int hgpk_poll(struct psmouse *psmouse)
 746 {
 747         /* We can't poll, so always return failure. */
 748         return -1;
 749 }
 750
 751 static int hgpk_reconnect(struct psmouse *psmouse)
 752 {
 753         struct hgpk_data *priv = psmouse->private;
 754
 755         /*
 756          * During suspend/resume the ps2 rails remain powered.  We don't want
 757          * to do a reset because it's flush data out of buffers; however,
 758          * earlier prototypes (B1) had some brokenness that required a reset.
 759          */
 760         if (olpc_board_at_least(olpc_board(0xb2)))
 761                 if (psmouse->ps2dev.serio->dev.power.power_state.event !=
 762                                 PM_EVENT_ON)
 763                         return 0;
 764
 765         priv->powered = 1;
 766         return hgpk_reset_device(psmouse, false);
 767 }
 768
 769 static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char *buf)
 770 {
 771         struct hgpk_data *priv = psmouse->private;
 772
 773         return sprintf(buf, "%d\n", priv->powered);
 774 }
 775
 776 static ssize_t hgpk_set_powered(struct psmouse *psmouse, void *data,
 777                                 const char *buf, size_t count)
 778 {
 779         struct hgpk_data *priv = psmouse->private;
 780         unsigned int value;
 781         int err;
 782
 783         err = kstrtouint(buf, 10, &value);
 784         if (err)
 785                 return err;
 786
 787         if (value > 1)
 788                 return -EINVAL;
 789
 790         if (value != priv->powered) {
 791                 /*
 792                  * hgpk_toggle_power will deal w/ state so
 793                  * we're not racing w/ irq
 794                  */
 795                 err = hgpk_toggle_powersave(psmouse, value);
 796                 if (!err)
 797                         priv->powered = value;
 798         }
 799
 800         return err ? err : count;
 801 }
 802
 803 __PSMOUSE_DEFINE_ATTR(powered, S_IWUSR | S_IRUGO, NULL,
 804                       hgpk_show_powered, hgpk_set_powered, false);
 805
 806 static ssize_t attr_show_mode(struct psmouse *psmouse, void *data, char *buf)
 807 {
 808         struct hgpk_data *priv = psmouse->private;
 809
 810         return sprintf(buf, "%s\n", hgpk_mode_names[priv->mode]);
 811 }
 812
 813 static ssize_t attr_set_mode(struct psmouse *psmouse, void *data,
 814                              const char *buf, size_t len)
 815 {
 816         struct hgpk_data *priv = psmouse->private;
 817         enum hgpk_mode old_mode = priv->mode;
 818         enum hgpk_mode new_mode = hgpk_mode_from_name(buf, len);
 819         struct input_dev *old_dev = psmouse->dev;
 820         struct input_dev *new_dev;
 821         int err;
 822
 823         if (new_mode == HGPK_MODE_INVALID)
 824                 return -EINVAL;
 825
 826         if (old_mode == new_mode)
 827                 return len;
 828
 829         new_dev = input_allocate_device();
 830         if (!new_dev)
 831                 return -ENOMEM;
 832
 833         psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
 834
 835         /* Switch device into the new mode */
 836         priv->mode = new_mode;
 837         err = hgpk_reset_device(psmouse, false);
 838         if (err)
 839                 goto err_try_restore;
 840
 841         hgpk_setup_input_device(new_dev, old_dev, new_mode);
 842
 843         psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
 844
 845         err = input_register_device(new_dev);
 846         if (err)
 847                 goto err_try_restore;
 848
 849         psmouse->dev = new_dev;
 850         input_unregister_device(old_dev);
 851
 852         return len;
 853
 854 err_try_restore:
 855         input_free_device(new_dev);
 856         priv->mode = old_mode;
 857         hgpk_reset_device(psmouse, false);
 858
 859         return err;
 860 }
 861
 862 PSMOUSE_DEFINE_ATTR(hgpk_mode, S_IWUSR | S_IRUGO, NULL,
 863                     attr_show_mode, attr_set_mode);
 864
 865 static ssize_t hgpk_trigger_recal_show(struct psmouse *psmouse,
 866                 void *data, char *buf)
 867 {
 868         return -EINVAL;
 869 }
 870
 871 static ssize_t hgpk_trigger_recal(struct psmouse *psmouse, void *data,
 872                                 const char *buf, size_t count)
 873 {
 874         struct hgpk_data *priv = psmouse->private;
 875         unsigned int value;
 876         int err;
 877
 878         err = kstrtouint(buf, 10, &value);
 879         if (err)
 880                 return err;
 881
 882         if (value != 1)
 883                 return -EINVAL;
 884
 885         /*
 886          * We queue work instead of doing recalibration right here
 887          * to avoid adding locking to to hgpk_force_recalibrate()
 888          * since workqueue provides serialization.
 889          */
 890         psmouse_queue_work(psmouse, &priv->recalib_wq, 0);
 891         return count;
 892 }
 893
 894 __PSMOUSE_DEFINE_ATTR(recalibrate, S_IWUSR | S_IRUGO, NULL,
 895                       hgpk_trigger_recal_show, hgpk_trigger_recal, false);
 896
 897 static void hgpk_disconnect(struct psmouse *psmouse)
 898 {
 899         struct hgpk_data *priv = psmouse->private;
 900
 901         device_remove_file(&psmouse->ps2dev.serio->dev,
 902                            &psmouse_attr_powered.dattr);
 903         device_remove_file(&psmouse->ps2dev.serio->dev,
 904                            &psmouse_attr_hgpk_mode.dattr);
 905
 906         if (psmouse->model >= HGPK_MODEL_C)
 907                 device_remove_file(&psmouse->ps2dev.serio->dev,
 908                                    &psmouse_attr_recalibrate.dattr);
 909
 910         psmouse_reset(psmouse);
 911         kfree(priv);
 912 }
 913
 914 static void hgpk_recalib_work(struct work_struct *work)
 915 {
 916         struct delayed_work *w = to_delayed_work(work);
 917         struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq);
 918         struct psmouse *psmouse = priv->psmouse;
 919
 920         if (hgpk_force_recalibrate(psmouse))
 921                 psmouse_err(psmouse, "recalibration failed!\n");
 922 }
 923
 924 static int hgpk_register(struct psmouse *psmouse)
 925 {
 926         struct hgpk_data *priv = psmouse->private;
 927         int err;
 928
 929         /* register handlers */
 930         psmouse->protocol_handler = hgpk_process_byte;
 931         psmouse->poll = hgpk_poll;
 932         psmouse->disconnect = hgpk_disconnect;
 933         psmouse->reconnect = hgpk_reconnect;
 934
 935         /* Disable the idle resync. */
 936         psmouse->resync_time = 0;
 937         /* Reset after a lot of bad bytes. */
 938         psmouse->resetafter = 1024;
 939
 940         hgpk_setup_input_device(psmouse->dev, NULL, priv->mode);
 941
 942         err = device_create_file(&psmouse->ps2dev.serio->dev,
 943                                  &psmouse_attr_powered.dattr);
 944         if (err) {
 945                 psmouse_err(psmouse, "Failed creating 'powered' sysfs node\n");
 946                 return err;
 947         }
 948
 949         err = device_create_file(&psmouse->ps2dev.serio->dev,
 950                                  &psmouse_attr_hgpk_mode.dattr);
 951         if (err) {
 952                 psmouse_err(psmouse,
 953                             "Failed creating 'hgpk_mode' sysfs node\n");
 954                 goto err_remove_powered;
 955         }
 956
 957         /* C-series touchpads added the recalibrate command */
 958         if (psmouse->model >= HGPK_MODEL_C) {
 959                 err = device_create_file(&psmouse->ps2dev.serio->dev,
 960                                          &psmouse_attr_recalibrate.dattr);
 961                 if (err) {
 962                         psmouse_err(psmouse,
 963                                     "Failed creating 'recalibrate' sysfs node\n");
 964                         goto err_remove_mode;
 965                 }
 966         }
 967
 968         return 0;
 969
 970 err_remove_mode:
 971         device_remove_file(&psmouse->ps2dev.serio->dev,
 972                            &psmouse_attr_hgpk_mode.dattr);
 973 err_remove_powered:
 974         device_remove_file(&psmouse->ps2dev.serio->dev,
 975                            &psmouse_attr_powered.dattr);
 976         return err;
 977 }
 978
 979 int hgpk_init(struct psmouse *psmouse)
 980 {
 981         struct hgpk_data *priv;
 982         int err;
 983
 984         priv = kzalloc(sizeof(struct hgpk_data), GFP_KERNEL);
 985         if (!priv) {
 986                 err = -ENOMEM;
 987                 goto alloc_fail;
 988         }
 989
 990         psmouse->private = priv;
 991
 992         priv->psmouse = psmouse;
 993         priv->powered = true;
 994         priv->mode = hgpk_default_mode;
 995         INIT_DELAYED_WORK(&priv->recalib_wq, hgpk_recalib_work);
 996
 997         err = hgpk_reset_device(psmouse, false);
 998         if (err)
 999                 goto init_fail;
1000
1001         err = hgpk_register(psmouse);
1002         if (err)
1003                 goto init_fail;
1004
1005         return 0;
1006
1007 init_fail:
1008         kfree(priv);
1009 alloc_fail:
1010         return err;
1011 }
1012
1013 static enum hgpk_model_t hgpk_get_model(struct psmouse *psmouse)
1014 {
1015         struct ps2dev *ps2dev = &psmouse->ps2dev;
1016         unsigned char param[3];
1017
1018         /* E7, E7, E7, E9 gets us a 3 byte identifier */
1019         if (ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1020             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1021             ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE21) ||
1022             ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) {
1023                 return -EIO;
1024         }
1025
1026         psmouse_dbg(psmouse, "ID: %*ph\n", 3, param);
1027
1028         /* HGPK signature: 0x67, 0x00, 0x<model> */
1029         if (param[0] != 0x67 || param[1] != 0x00)
1030                 return -ENODEV;
1031
1032         psmouse_info(psmouse, "OLPC touchpad revision 0x%x\n", param[2]);
1033
1034         return param[2];
1035 }
1036
1037 int hgpk_detect(struct psmouse *psmouse, bool set_properties)
1038 {
1039         int version;
1040
1041         version = hgpk_get_model(psmouse);
1042         if (version < 0)
1043                 return version;
1044
1045         if (set_properties) {
1046                 psmouse->vendor = "ALPS";
1047                 psmouse->name = "HGPK";
1048                 psmouse->model = version;
1049         }
1050
1051         return 0;
1052 }
1053
1054 void hgpk_module_init(void)
1055 {
1056         hgpk_default_mode = hgpk_mode_from_name(hgpk_mode_name,
1057                                                 strlen(hgpk_mode_name));
1058         if (hgpk_default_mode == HGPK_MODE_INVALID) {
1059                 hgpk_default_mode = HGPK_MODE_MOUSE;
1060                 strlcpy(hgpk_mode_name, hgpk_mode_names[HGPK_MODE_MOUSE],
1061                         sizeof(hgpk_mode_name));
1062         }
1063 }