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 } 1064