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/input.h> 34 #include <linux/serio.h> 35 #include <linux/libps2.h> 36 #include <linux/delay.h> 37 #include <asm/olpc.h> 38 39 #include "psmouse.h" 40 #include "hgpk.h" 41 42 static int tpdebug; 43 module_param(tpdebug, int, 0644); 44 MODULE_PARM_DESC(tpdebug, "enable debugging, dumping packets to KERN_DEBUG."); 45 46 static int recalib_delta = 100; 47 module_param(recalib_delta, int, 0644); 48 MODULE_PARM_DESC(recalib_delta, 49 "packets containing a delta this large will cause a recalibration."); 50 51 static int jumpy_delay = 1000; 52 module_param(jumpy_delay, int, 0644); 53 MODULE_PARM_DESC(jumpy_delay, 54 "delay (ms) before recal after jumpiness detected"); 55 56 static int spew_delay = 1000; 57 module_param(spew_delay, int, 0644); 58 MODULE_PARM_DESC(spew_delay, 59 "delay (ms) before recal after packet spew detected"); 60 61 static int recal_guard_time = 2000; 62 module_param(recal_guard_time, int, 0644); 63 MODULE_PARM_DESC(recal_guard_time, 64 "interval (ms) during which recal will be restarted if packet received"); 65 66 static int post_interrupt_delay = 1000; 67 module_param(post_interrupt_delay, int, 0644); 68 MODULE_PARM_DESC(post_interrupt_delay, 69 "delay (ms) before recal after recal interrupt detected"); 70 71 static int autorecal = 1; 72 module_param(autorecal, int, 0644); 73 MODULE_PARM_DESC(autorecal, "enable recalibration in the driver"); 74 75 /* 76 * When the touchpad gets ultra-sensitive, one can keep their finger 1/2" 77 * above the pad and still have it send packets. This causes a jump cursor 78 * when one places their finger on the pad. We can probably detect the 79 * jump as we see a large deltas (>= 100px). In mouse mode, I've been 80 * unable to even come close to 100px deltas during normal usage, so I think 81 * this threshold is safe. If a large delta occurs, trigger a recalibration. 82 */ 83 static void hgpk_jumpy_hack(struct psmouse *psmouse, int x, int y) 84 { 85 struct hgpk_data *priv = psmouse->private; 86 87 if (abs(x) > recalib_delta || abs(y) > recalib_delta) { 88 hgpk_err(psmouse, ">%dpx jump detected (%d,%d)\n", 89 recalib_delta, x, y); 90 /* My car gets forty rods to the hogshead and that's the 91 * way I likes it! */ 92 psmouse_queue_work(psmouse, &priv->recalib_wq, 93 msecs_to_jiffies(jumpy_delay)); 94 } 95 } 96 97 /* 98 * We have no idea why this particular hardware bug occurs. The touchpad 99 * will randomly start spewing packets without anything touching the 100 * pad. This wouldn't necessarily be bad, but it's indicative of a 101 * severely miscalibrated pad; attempting to use the touchpad while it's 102 * spewing means the cursor will jump all over the place, and act "drunk". 103 * 104 * The packets that are spewed tend to all have deltas between -2 and 2, and 105 * the cursor will move around without really going very far. It will 106 * tend to end up in the same location; if we tally up the changes over 107 * 100 packets, we end up w/ a final delta of close to 0. This happens 108 * pretty regularly when the touchpad is spewing, and is pretty hard to 109 * manually trigger (at least for *my* fingers). So, it makes a perfect 110 * scheme for detecting spews. 111 */ 112 static void hgpk_spewing_hack(struct psmouse *psmouse, 113 int l, int r, int x, int y) 114 { 115 struct hgpk_data *priv = psmouse->private; 116 117 /* ignore button press packets; many in a row could trigger 118 * a false-positive! */ 119 if (l || r) 120 return; 121 122 priv->x_tally += x; 123 priv->y_tally += y; 124 125 if (++priv->count > 100) { 126 if (abs(priv->x_tally) < 3 && abs(priv->y_tally) < 3) { 127 hgpk_dbg(psmouse, "packet spew detected (%d,%d)\n", 128 priv->x_tally, priv->y_tally); 129 psmouse_queue_work(psmouse, &priv->recalib_wq, 130 msecs_to_jiffies(spew_delay)); 131 } 132 /* reset every 100 packets */ 133 priv->count = 0; 134 priv->x_tally = 0; 135 priv->y_tally = 0; 136 } 137 } 138 139 /* 140 * HGPK Mouse Mode format (standard mouse format, sans middle button) 141 * 142 * byte 0: y-over x-over y-neg x-neg 1 0 swr swl 143 * byte 1: x7 x6 x5 x4 x3 x2 x1 x0 144 * byte 2: y7 y6 y5 y4 y3 y2 y1 y0 145 * 146 * swr/swl are the left/right buttons. 147 * x-neg/y-neg are the x and y delta negative bits 148 * x-over/y-over are the x and y overflow bits 149 */ 150 static int hgpk_validate_byte(unsigned char *packet) 151 { 152 return (packet[0] & 0x0C) != 0x08; 153 } 154 155 static void hgpk_process_packet(struct psmouse *psmouse) 156 { 157 struct input_dev *dev = psmouse->dev; 158 unsigned char *packet = psmouse->packet; 159 int x, y, left, right; 160 161 left = packet[0] & 1; 162 right = (packet[0] >> 1) & 1; 163 164 x = packet[1] - ((packet[0] << 4) & 0x100); 165 y = ((packet[0] << 3) & 0x100) - packet[2]; 166 167 hgpk_jumpy_hack(psmouse, x, y); 168 hgpk_spewing_hack(psmouse, left, right, x, y); 169 170 if (tpdebug) 171 hgpk_dbg(psmouse, "l=%d r=%d x=%d y=%d\n", left, right, x, y); 172 173 input_report_key(dev, BTN_LEFT, left); 174 input_report_key(dev, BTN_RIGHT, right); 175 176 input_report_rel(dev, REL_X, x); 177 input_report_rel(dev, REL_Y, y); 178 179 input_sync(dev); 180 } 181 182 static psmouse_ret_t hgpk_process_byte(struct psmouse *psmouse) 183 { 184 struct hgpk_data *priv = psmouse->private; 185 186 if (hgpk_validate_byte(psmouse->packet)) { 187 hgpk_dbg(psmouse, "%s: (%d) %02x %02x %02x\n", 188 __func__, psmouse->pktcnt, psmouse->packet[0], 189 psmouse->packet[1], psmouse->packet[2]); 190 return PSMOUSE_BAD_DATA; 191 } 192 193 if (psmouse->pktcnt >= psmouse->pktsize) { 194 hgpk_process_packet(psmouse); 195 return PSMOUSE_FULL_PACKET; 196 } 197 198 if (priv->recalib_window) { 199 if (time_before(jiffies, priv->recalib_window)) { 200 /* 201 * ugh, got a packet inside our recalibration 202 * window, schedule another recalibration. 203 */ 204 hgpk_dbg(psmouse, 205 "packet inside calibration window, " 206 "queueing another recalibration\n"); 207 psmouse_queue_work(psmouse, &priv->recalib_wq, 208 msecs_to_jiffies(post_interrupt_delay)); 209 } 210 priv->recalib_window = 0; 211 } 212 213 return PSMOUSE_GOOD_DATA; 214 } 215 216 static int hgpk_force_recalibrate(struct psmouse *psmouse) 217 { 218 struct ps2dev *ps2dev = &psmouse->ps2dev; 219 struct hgpk_data *priv = psmouse->private; 220 221 /* C-series touchpads added the recalibrate command */ 222 if (psmouse->model < HGPK_MODEL_C) 223 return 0; 224 225 /* we don't want to race with the irq handler, nor with resyncs */ 226 psmouse_set_state(psmouse, PSMOUSE_INITIALIZING); 227 228 /* start by resetting the device */ 229 psmouse_reset(psmouse); 230 231 /* send the recalibrate request */ 232 if (ps2_command(ps2dev, NULL, 0xf5) || 233 ps2_command(ps2dev, NULL, 0xf5) || 234 ps2_command(ps2dev, NULL, 0xe6) || 235 ps2_command(ps2dev, NULL, 0xf5)) { 236 return -1; 237 } 238 239 /* according to ALPS, 150mS is required for recalibration */ 240 msleep(150); 241 242 /* XXX: If a finger is down during this delay, recalibration will 243 * detect capacitance incorrectly. This is a hardware bug, and 244 * we don't have a good way to deal with it. The 2s window stuff 245 * (below) is our best option for now. 246 */ 247 248 if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE)) 249 return -1; 250 251 psmouse_set_state(psmouse, PSMOUSE_ACTIVATED); 252 253 /* After we recalibrate, we shouldn't get any packets for 2s. If 254 * we do, it's likely that someone's finger was on the touchpad. 255 * If someone's finger *was* on the touchpad, it's probably 256 * miscalibrated. So, we should schedule another recalibration 257 */ 258 priv->recalib_window = jiffies + msecs_to_jiffies(recal_guard_time); 259 260 return 0; 261 } 262 263 /* 264 * This kills power to the touchpad; according to ALPS, current consumption 265 * goes down to 50uA after running this. To turn power back on, we drive 266 * MS-DAT low. 267 */ 268 static int hgpk_toggle_power(struct psmouse *psmouse, int enable) 269 { 270 struct ps2dev *ps2dev = &psmouse->ps2dev; 271 int timeo; 272 273 /* Added on D-series touchpads */ 274 if (psmouse->model < HGPK_MODEL_D) 275 return 0; 276 277 if (enable) { 278 psmouse_set_state(psmouse, PSMOUSE_INITIALIZING); 279 280 /* 281 * Sending a byte will drive MS-DAT low; this will wake up 282 * the controller. Once we get an ACK back from it, it 283 * means we can continue with the touchpad re-init. ALPS 284 * tells us that 1s should be long enough, so set that as 285 * the upper bound. 286 */ 287 for (timeo = 20; timeo > 0; timeo--) { 288 if (!ps2_sendbyte(&psmouse->ps2dev, 289 PSMOUSE_CMD_DISABLE, 20)) 290 break; 291 msleep(50); 292 } 293 294 psmouse_reset(psmouse); 295 296 /* should be all set, enable the touchpad */ 297 ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE); 298 psmouse_set_state(psmouse, PSMOUSE_ACTIVATED); 299 300 } else { 301 hgpk_dbg(psmouse, "Powering off touchpad.\n"); 302 psmouse_set_state(psmouse, PSMOUSE_IGNORE); 303 304 if (ps2_command(ps2dev, NULL, 0xec) || 305 ps2_command(ps2dev, NULL, 0xec) || 306 ps2_command(ps2dev, NULL, 0xea)) { 307 return -1; 308 } 309 310 /* probably won't see an ACK, the touchpad will be off */ 311 ps2_sendbyte(&psmouse->ps2dev, 0xec, 20); 312 } 313 314 return 0; 315 } 316 317 static int hgpk_poll(struct psmouse *psmouse) 318 { 319 /* We can't poll, so always return failure. */ 320 return -1; 321 } 322 323 static int hgpk_reconnect(struct psmouse *psmouse) 324 { 325 /* During suspend/resume the ps2 rails remain powered. We don't want 326 * to do a reset because it's flush data out of buffers; however, 327 * earlier prototypes (B1) had some brokenness that required a reset. */ 328 if (olpc_board_at_least(olpc_board(0xb2))) 329 if (psmouse->ps2dev.serio->dev.power.power_state.event != 330 PM_EVENT_ON) 331 return 0; 332 333 psmouse_reset(psmouse); 334 335 return 0; 336 } 337 338 static ssize_t hgpk_show_powered(struct psmouse *psmouse, void *data, char *buf) 339 { 340 struct hgpk_data *priv = psmouse->private; 341 342 return sprintf(buf, "%d\n", priv->powered); 343 } 344 345 static ssize_t hgpk_set_powered(struct psmouse *psmouse, void *data, 346 const char *buf, size_t count) 347 { 348 struct hgpk_data *priv = psmouse->private; 349 unsigned long value; 350 int err; 351 352 err = strict_strtoul(buf, 10, &value); 353 if (err || value > 1) 354 return -EINVAL; 355 356 if (value != priv->powered) { 357 /* 358 * hgpk_toggle_power will deal w/ state so 359 * we're not racing w/ irq 360 */ 361 err = hgpk_toggle_power(psmouse, value); 362 if (!err) 363 priv->powered = value; 364 } 365 366 return err ? err : count; 367 } 368 369 __PSMOUSE_DEFINE_ATTR(powered, S_IWUSR | S_IRUGO, NULL, 370 hgpk_show_powered, hgpk_set_powered, 0); 371 372 static void hgpk_disconnect(struct psmouse *psmouse) 373 { 374 struct hgpk_data *priv = psmouse->private; 375 376 device_remove_file(&psmouse->ps2dev.serio->dev, 377 &psmouse_attr_powered.dattr); 378 psmouse_reset(psmouse); 379 kfree(priv); 380 } 381 382 static void hgpk_recalib_work(struct work_struct *work) 383 { 384 struct delayed_work *w = container_of(work, struct delayed_work, work); 385 struct hgpk_data *priv = container_of(w, struct hgpk_data, recalib_wq); 386 struct psmouse *psmouse = priv->psmouse; 387 388 hgpk_dbg(psmouse, "recalibrating touchpad..\n"); 389 390 if (hgpk_force_recalibrate(psmouse)) 391 hgpk_err(psmouse, "recalibration failed!\n"); 392 } 393 394 static int hgpk_register(struct psmouse *psmouse) 395 { 396 struct input_dev *dev = psmouse->dev; 397 int err; 398 399 /* unset the things that psmouse-base sets which we don't have */ 400 __clear_bit(BTN_MIDDLE, dev->keybit); 401 402 /* set the things we do have */ 403 __set_bit(EV_KEY, dev->evbit); 404 __set_bit(EV_REL, dev->evbit); 405 406 __set_bit(REL_X, dev->relbit); 407 __set_bit(REL_Y, dev->relbit); 408 409 __set_bit(BTN_LEFT, dev->keybit); 410 __set_bit(BTN_RIGHT, dev->keybit); 411 412 /* register handlers */ 413 psmouse->protocol_handler = hgpk_process_byte; 414 psmouse->poll = hgpk_poll; 415 psmouse->disconnect = hgpk_disconnect; 416 psmouse->reconnect = hgpk_reconnect; 417 psmouse->pktsize = 3; 418 419 /* Disable the idle resync. */ 420 psmouse->resync_time = 0; 421 /* Reset after a lot of bad bytes. */ 422 psmouse->resetafter = 1024; 423 424 err = device_create_file(&psmouse->ps2dev.serio->dev, 425 &psmouse_attr_powered.dattr); 426 if (err) 427 hgpk_err(psmouse, "Failed to create sysfs attribute\n"); 428 429 return err; 430 } 431 432 int hgpk_init(struct psmouse *psmouse) 433 { 434 struct hgpk_data *priv; 435 int err = -ENOMEM; 436 437 priv = kzalloc(sizeof(struct hgpk_data), GFP_KERNEL); 438 if (!priv) 439 goto alloc_fail; 440 441 psmouse->private = priv; 442 priv->psmouse = psmouse; 443 priv->powered = 1; 444 INIT_DELAYED_WORK(&priv->recalib_wq, hgpk_recalib_work); 445 446 err = psmouse_reset(psmouse); 447 if (err) 448 goto init_fail; 449 450 err = hgpk_register(psmouse); 451 if (err) 452 goto init_fail; 453 454 return 0; 455 456 init_fail: 457 kfree(priv); 458 alloc_fail: 459 return err; 460 } 461 462 static enum hgpk_model_t hgpk_get_model(struct psmouse *psmouse) 463 { 464 struct ps2dev *ps2dev = &psmouse->ps2dev; 465 unsigned char param[3]; 466 467 /* E7, E7, E7, E9 gets us a 3 byte identifier */ 468 if (ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) || 469 ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) || 470 ps2_command(ps2dev, NULL, PSMOUSE_CMD_SETSCALE21) || 471 ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO)) { 472 return -EIO; 473 } 474 475 hgpk_dbg(psmouse, "ID: %02x %02x %02x", param[0], param[1], param[2]); 476 477 /* HGPK signature: 0x67, 0x00, 0x<model> */ 478 if (param[0] != 0x67 || param[1] != 0x00) 479 return -ENODEV; 480 481 hgpk_info(psmouse, "OLPC touchpad revision 0x%x\n", param[2]); 482 483 return param[2]; 484 } 485 486 int hgpk_detect(struct psmouse *psmouse, int set_properties) 487 { 488 int version; 489 490 version = hgpk_get_model(psmouse); 491 if (version < 0) 492 return version; 493 494 if (set_properties) { 495 psmouse->vendor = "ALPS"; 496 psmouse->name = "HGPK"; 497 psmouse->model = version; 498 } 499 500 return 0; 501 } 502