kernel/drivers/input/touchscreen/wacom_w8001.c

   1 /*
   2  * Wacom W8001 penabled serial touchscreen driver
   3  *
   4  * Copyright (c) 2008 Jaya Kumar
   5  * Copyright (c) 2010 Red Hat, Inc.
   6  * Copyright (c) 2010 - 2011 Ping Cheng, Wacom. <pingc@wacom.com>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License. See the file COPYING in the main directory of this archive for
  10  * more details.
  11  *
  12  * Layout based on Elo serial touchscreen driver by Vojtech Pavlik
  13  */
  14
  15 #include <linux/errno.h>
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/slab.h>
  19 #include <linux/input/mt.h>
  20 #include <linux/serio.h>
  21 #include <linux/ctype.h>
  22 #include <linux/delay.h>
  23
  24 #define DRIVER_DESC     "Wacom W8001 serial touchscreen driver"
  25
  26 MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
  27 MODULE_DESCRIPTION(DRIVER_DESC);
  28 MODULE_LICENSE("GPL");
  29
  30 #define W8001_MAX_LENGTH        11
  31 #define W8001_LEAD_MASK         0x80
  32 #define W8001_LEAD_BYTE         0x80
  33 #define W8001_TAB_MASK          0x40
  34 #define W8001_TAB_BYTE          0x40
  35 /* set in first byte of touch data packets */
  36 #define W8001_TOUCH_MASK        (0x10 | W8001_LEAD_MASK)
  37 #define W8001_TOUCH_BYTE        (0x10 | W8001_LEAD_BYTE)
  38
  39 #define W8001_QUERY_PACKET      0x20
  40
  41 #define W8001_CMD_STOP          '0'
  42 #define W8001_CMD_START         '1'
  43 #define W8001_CMD_QUERY         '*'
  44 #define W8001_CMD_TOUCHQUERY    '%'
  45
  46 /* length of data packets in bytes, depends on device. */
  47 #define W8001_PKTLEN_TOUCH93    5
  48 #define W8001_PKTLEN_TOUCH9A    7
  49 #define W8001_PKTLEN_TPCPEN     9
  50 #define W8001_PKTLEN_TPCCTL     11      /* control packet */
  51 #define W8001_PKTLEN_TOUCH2FG   13
  52
  53 /* resolution in points/mm */
  54 #define W8001_PEN_RESOLUTION    100
  55 #define W8001_TOUCH_RESOLUTION  10
  56
  57 struct w8001_coord {
  58         u8 rdy;
  59         u8 tsw;
  60         u8 f1;
  61         u8 f2;
  62         u16 x;
  63         u16 y;
  64         u16 pen_pressure;
  65         u8 tilt_x;
  66         u8 tilt_y;
  67 };
  68
  69 /* touch query reply packet */
  70 struct w8001_touch_query {
  71         u16 x;
  72         u16 y;
  73         u8 panel_res;
  74         u8 capacity_res;
  75         u8 sensor_id;
  76 };
  77
  78 /*
  79  * Per-touchscreen data.
  80  */
  81
  82 struct w8001 {
  83         struct input_dev *dev;
  84         struct serio *serio;
  85         struct completion cmd_done;
  86         int id;
  87         int idx;
  88         unsigned char response_type;
  89         unsigned char response[W8001_MAX_LENGTH];
  90         unsigned char data[W8001_MAX_LENGTH];
  91         char phys[32];
  92         int type;
  93         unsigned int pktlen;
  94         u16 max_touch_x;
  95         u16 max_touch_y;
  96         u16 max_pen_x;
  97         u16 max_pen_y;
  98         char name[64];
  99 };
 100
 101 static void parse_pen_data(u8 *data, struct w8001_coord *coord)
 102 {
 103         memset(coord, 0, sizeof(*coord));
 104
 105         coord->rdy = data[0] & 0x20;
 106         coord->tsw = data[0] & 0x01;
 107         coord->f1 = data[0] & 0x02;
 108         coord->f2 = data[0] & 0x04;
 109
 110         coord->x = (data[1] & 0x7F) << 9;
 111         coord->x |= (data[2] & 0x7F) << 2;
 112         coord->x |= (data[6] & 0x60) >> 5;
 113
 114         coord->y = (data[3] & 0x7F) << 9;
 115         coord->y |= (data[4] & 0x7F) << 2;
 116         coord->y |= (data[6] & 0x18) >> 3;
 117
 118         coord->pen_pressure = data[5] & 0x7F;
 119         coord->pen_pressure |= (data[6] & 0x07) << 7 ;
 120
 121         coord->tilt_x = data[7] & 0x7F;
 122         coord->tilt_y = data[8] & 0x7F;
 123 }
 124
 125 static void parse_single_touch(u8 *data, struct w8001_coord *coord)
 126 {
 127         coord->x = (data[1] << 7) | data[2];
 128         coord->y = (data[3] << 7) | data[4];
 129         coord->tsw = data[0] & 0x01;
 130 }
 131
 132 static void scale_touch_coordinates(struct w8001 *w8001,
 133                                     unsigned int *x, unsigned int *y)
 134 {
 135         if (w8001->max_pen_x && w8001->max_touch_x)
 136                 *x = *x * w8001->max_pen_x / w8001->max_touch_x;
 137
 138         if (w8001->max_pen_y && w8001->max_touch_y)
 139                 *y = *y * w8001->max_pen_y / w8001->max_touch_y;
 140 }
 141
 142 static void parse_multi_touch(struct w8001 *w8001)
 143 {
 144         struct input_dev *dev = w8001->dev;
 145         unsigned char *data = w8001->data;
 146         unsigned int x, y;
 147         int i;
 148         int count = 0;
 149
 150         for (i = 0; i < 2; i++) {
 151                 bool touch = data[0] & (1 << i);
 152
 153                 input_mt_slot(dev, i);
 154                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, touch);
 155                 if (touch) {
 156                         x = (data[6 * i + 1] << 7) | data[6 * i + 2];
 157                         y = (data[6 * i + 3] << 7) | data[6 * i + 4];
 158                         /* data[5,6] and [11,12] is finger capacity */
 159
 160                         /* scale to pen maximum */
 161                         scale_touch_coordinates(w8001, &x, &y);
 162
 163                         input_report_abs(dev, ABS_MT_POSITION_X, x);
 164                         input_report_abs(dev, ABS_MT_POSITION_Y, y);
 165                         count++;
 166                 }
 167         }
 168
 169         /* emulate single touch events when stylus is out of proximity.
 170          * This is to make single touch backward support consistent
 171          * across all Wacom single touch devices.
 172          */
 173         if (w8001->type != BTN_TOOL_PEN &&
 174                             w8001->type != BTN_TOOL_RUBBER) {
 175                 w8001->type = count == 1 ? BTN_TOOL_FINGER : KEY_RESERVED;
 176                 input_mt_report_pointer_emulation(dev, true);
 177         }
 178
 179         input_sync(dev);
 180 }
 181
 182 static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
 183 {
 184         memset(query, 0, sizeof(*query));
 185
 186         query->panel_res = data[1];
 187         query->sensor_id = data[2] & 0x7;
 188         query->capacity_res = data[7];
 189
 190         query->x = data[3] << 9;
 191         query->x |= data[4] << 2;
 192         query->x |= (data[2] >> 5) & 0x3;
 193
 194         query->y = data[5] << 9;
 195         query->y |= data[6] << 2;
 196         query->y |= (data[2] >> 3) & 0x3;
 197
 198         /* Early days' single-finger touch models need the following defaults */
 199         if (!query->x && !query->y) {
 200                 query->x = 1024;
 201                 query->y = 1024;
 202                 if (query->panel_res)
 203                         query->x = query->y = (1 << query->panel_res);
 204                 query->panel_res = W8001_TOUCH_RESOLUTION;
 205         }
 206 }
 207
 208 static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
 209 {
 210         struct input_dev *dev = w8001->dev;
 211
 212         /*
 213          * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
 214          * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
 215          * or eraser. Assume:
 216          * - if dev is already in proximity and f2 is toggled → pen + side2
 217          * - if dev comes into proximity with f2 set → eraser
 218          * If f2 disappears after assuming eraser, fake proximity out for
 219          * eraser and in for pen.
 220          */
 221
 222         switch (w8001->type) {
 223         case BTN_TOOL_RUBBER:
 224                 if (!coord->f2) {
 225                         input_report_abs(dev, ABS_PRESSURE, 0);
 226                         input_report_key(dev, BTN_TOUCH, 0);
 227                         input_report_key(dev, BTN_STYLUS, 0);
 228                         input_report_key(dev, BTN_STYLUS2, 0);
 229                         input_report_key(dev, BTN_TOOL_RUBBER, 0);
 230                         input_sync(dev);
 231                         w8001->type = BTN_TOOL_PEN;
 232                 }
 233                 break;
 234
 235         case BTN_TOOL_FINGER:
 236                 input_report_key(dev, BTN_TOUCH, 0);
 237                 input_report_key(dev, BTN_TOOL_FINGER, 0);
 238                 input_sync(dev);
 239                 /* fall through */
 240
 241         case KEY_RESERVED:
 242                 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
 243                 break;
 244
 245         default:
 246                 input_report_key(dev, BTN_STYLUS2, coord->f2);
 247                 break;
 248         }
 249
 250         input_report_abs(dev, ABS_X, coord->x);
 251         input_report_abs(dev, ABS_Y, coord->y);
 252         input_report_abs(dev, ABS_PRESSURE, coord->pen_pressure);
 253         input_report_key(dev, BTN_TOUCH, coord->tsw);
 254         input_report_key(dev, BTN_STYLUS, coord->f1);
 255         input_report_key(dev, w8001->type, coord->rdy);
 256         input_sync(dev);
 257
 258         if (!coord->rdy)
 259                 w8001->type = KEY_RESERVED;
 260 }
 261
 262 static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord)
 263 {
 264         struct input_dev *dev = w8001->dev;
 265         unsigned int x = coord->x;
 266         unsigned int y = coord->y;
 267
 268         /* scale to pen maximum */
 269         scale_touch_coordinates(w8001, &x, &y);
 270
 271         input_report_abs(dev, ABS_X, x);
 272         input_report_abs(dev, ABS_Y, y);
 273         input_report_key(dev, BTN_TOUCH, coord->tsw);
 274         input_report_key(dev, BTN_TOOL_FINGER, coord->tsw);
 275
 276         input_sync(dev);
 277
 278         w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED;
 279 }
 280
 281 static irqreturn_t w8001_interrupt(struct serio *serio,
 282                                    unsigned char data, unsigned int flags)
 283 {
 284         struct w8001 *w8001 = serio_get_drvdata(serio);
 285         struct w8001_coord coord;
 286         unsigned char tmp;
 287
 288         w8001->data[w8001->idx] = data;
 289         switch (w8001->idx++) {
 290         case 0:
 291                 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
 292                         pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
 293                         w8001->idx = 0;
 294                 }
 295                 break;
 296
 297         case W8001_PKTLEN_TOUCH93 - 1:
 298         case W8001_PKTLEN_TOUCH9A - 1:
 299                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
 300                 if (tmp != W8001_TOUCH_BYTE)
 301                         break;
 302
 303                 if (w8001->pktlen == w8001->idx) {
 304                         w8001->idx = 0;
 305                         if (w8001->type != BTN_TOOL_PEN &&
 306                             w8001->type != BTN_TOOL_RUBBER) {
 307                                 parse_single_touch(w8001->data, &coord);
 308                                 report_single_touch(w8001, &coord);
 309                         }
 310                 }
 311                 break;
 312
 313         /* Pen coordinates packet */
 314         case W8001_PKTLEN_TPCPEN - 1:
 315                 tmp = w8001->data[0] & W8001_TAB_MASK;
 316                 if (unlikely(tmp == W8001_TAB_BYTE))
 317                         break;
 318
 319                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
 320                 if (tmp == W8001_TOUCH_BYTE)
 321                         break;
 322
 323                 w8001->idx = 0;
 324                 parse_pen_data(w8001->data, &coord);
 325                 report_pen_events(w8001, &coord);
 326                 break;
 327
 328         /* control packet */
 329         case W8001_PKTLEN_TPCCTL - 1:
 330                 tmp = w8001->data[0] & W8001_TOUCH_MASK;
 331                 if (tmp == W8001_TOUCH_BYTE)
 332                         break;
 333
 334                 w8001->idx = 0;
 335                 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
 336                 w8001->response_type = W8001_QUERY_PACKET;
 337                 complete(&w8001->cmd_done);
 338                 break;
 339
 340         /* 2 finger touch packet */
 341         case W8001_PKTLEN_TOUCH2FG - 1:
 342                 w8001->idx = 0;
 343                 parse_multi_touch(w8001);
 344                 break;
 345         }
 346
 347         return IRQ_HANDLED;
 348 }
 349
 350 static int w8001_command(struct w8001 *w8001, unsigned char command,
 351                          bool wait_response)
 352 {
 353         int rc;
 354
 355         w8001->response_type = 0;
 356         init_completion(&w8001->cmd_done);
 357
 358         rc = serio_write(w8001->serio, command);
 359         if (rc == 0 && wait_response) {
 360
 361                 wait_for_completion_timeout(&w8001->cmd_done, HZ);
 362                 if (w8001->response_type != W8001_QUERY_PACKET)
 363                         rc = -EIO;
 364         }
 365
 366         return rc;
 367 }
 368
 369 static int w8001_open(struct input_dev *dev)
 370 {
 371         struct w8001 *w8001 = input_get_drvdata(dev);
 372
 373         return w8001_command(w8001, W8001_CMD_START, false);
 374 }
 375
 376 static void w8001_close(struct input_dev *dev)
 377 {
 378         struct w8001 *w8001 = input_get_drvdata(dev);
 379
 380         w8001_command(w8001, W8001_CMD_STOP, false);
 381 }
 382
 383 static int w8001_setup(struct w8001 *w8001)
 384 {
 385         struct input_dev *dev = w8001->dev;
 386         struct w8001_coord coord;
 387         struct w8001_touch_query touch;
 388         int error;
 389
 390         error = w8001_command(w8001, W8001_CMD_STOP, false);
 391         if (error)
 392                 return error;
 393
 394         msleep(250);    /* wait 250ms before querying the device */
 395
 396         dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 397         strlcat(w8001->name, "Wacom Serial", sizeof(w8001->name));
 398
 399         __set_bit(INPUT_PROP_DIRECT, dev->propbit);
 400
 401         /* penabled? */
 402         error = w8001_command(w8001, W8001_CMD_QUERY, true);
 403         if (!error) {
 404                 __set_bit(BTN_TOUCH, dev->keybit);
 405                 __set_bit(BTN_TOOL_PEN, dev->keybit);
 406                 __set_bit(BTN_TOOL_RUBBER, dev->keybit);
 407                 __set_bit(BTN_STYLUS, dev->keybit);
 408                 __set_bit(BTN_STYLUS2, dev->keybit);
 409
 410                 parse_pen_data(w8001->response, &coord);
 411                 w8001->max_pen_x = coord.x;
 412                 w8001->max_pen_y = coord.y;
 413
 414                 input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
 415                 input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
 416                 input_abs_set_res(dev, ABS_X, W8001_PEN_RESOLUTION);
 417                 input_abs_set_res(dev, ABS_Y, W8001_PEN_RESOLUTION);
 418                 input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
 419                 if (coord.tilt_x && coord.tilt_y) {
 420                         input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
 421                         input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
 422                 }
 423                 w8001->id = 0x90;
 424                 strlcat(w8001->name, " Penabled", sizeof(w8001->name));
 425         }
 426
 427         /* Touch enabled? */
 428         error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
 429
 430         /*
 431          * Some non-touch devices may reply to the touch query. But their
 432          * second byte is empty, which indicates touch is not supported.
 433          */
 434         if (!error && w8001->response[1]) {
 435                 __set_bit(BTN_TOUCH, dev->keybit);
 436                 __set_bit(BTN_TOOL_FINGER, dev->keybit);
 437
 438                 parse_touchquery(w8001->response, &touch);
 439                 w8001->max_touch_x = touch.x;
 440                 w8001->max_touch_y = touch.y;
 441
 442                 if (w8001->max_pen_x && w8001->max_pen_y) {
 443                         /* if pen is supported scale to pen maximum */
 444                         touch.x = w8001->max_pen_x;
 445                         touch.y = w8001->max_pen_y;
 446                         touch.panel_res = W8001_PEN_RESOLUTION;
 447                 }
 448
 449                 input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
 450                 input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
 451                 input_abs_set_res(dev, ABS_X, touch.panel_res);
 452                 input_abs_set_res(dev, ABS_Y, touch.panel_res);
 453
 454                 switch (touch.sensor_id) {
 455                 case 0:
 456                 case 2:
 457                         w8001->pktlen = W8001_PKTLEN_TOUCH93;
 458                         w8001->id = 0x93;
 459                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
 460                         break;
 461
 462                 case 1:
 463                 case 3:
 464                 case 4:
 465                         w8001->pktlen = W8001_PKTLEN_TOUCH9A;
 466                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
 467                         w8001->id = 0x9a;
 468                         break;
 469
 470                 case 5:
 471                         w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
 472
 473                         input_mt_init_slots(dev, 2, 0);
 474                         input_set_abs_params(dev, ABS_MT_POSITION_X,
 475                                                 0, touch.x, 0, 0);
 476                         input_set_abs_params(dev, ABS_MT_POSITION_Y,
 477                                                 0, touch.y, 0, 0);
 478                         input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
 479                                                 0, MT_TOOL_MAX, 0, 0);
 480
 481                         strlcat(w8001->name, " 2FG", sizeof(w8001->name));
 482                         if (w8001->max_pen_x && w8001->max_pen_y)
 483                                 w8001->id = 0xE3;
 484                         else
 485                                 w8001->id = 0xE2;
 486                         break;
 487                 }
 488         }
 489
 490         strlcat(w8001->name, " Touchscreen", sizeof(w8001->name));
 491
 492         return 0;
 493 }
 494
 495 /*
 496  * w8001_disconnect() is the opposite of w8001_connect()
 497  */
 498
 499 static void w8001_disconnect(struct serio *serio)
 500 {
 501         struct w8001 *w8001 = serio_get_drvdata(serio);
 502
 503         serio_close(serio);
 504
 505         input_unregister_device(w8001->dev);
 506         kfree(w8001);
 507
 508         serio_set_drvdata(serio, NULL);
 509 }
 510
 511 /*
 512  * w8001_connect() is the routine that is called when someone adds a
 513  * new serio device that supports the w8001 protocol and registers it as
 514  * an input device.
 515  */
 516
 517 static int w8001_connect(struct serio *serio, struct serio_driver *drv)
 518 {
 519         struct w8001 *w8001;
 520         struct input_dev *input_dev;
 521         int err;
 522
 523         w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
 524         input_dev = input_allocate_device();
 525         if (!w8001 || !input_dev) {
 526                 err = -ENOMEM;
 527                 goto fail1;
 528         }
 529
 530         w8001->serio = serio;
 531         w8001->dev = input_dev;
 532         init_completion(&w8001->cmd_done);
 533         snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
 534
 535         serio_set_drvdata(serio, w8001);
 536         err = serio_open(serio, drv);
 537         if (err)
 538                 goto fail2;
 539
 540         err = w8001_setup(w8001);
 541         if (err)
 542                 goto fail3;
 543
 544         input_dev->name = w8001->name;
 545         input_dev->phys = w8001->phys;
 546         input_dev->id.product = w8001->id;
 547         input_dev->id.bustype = BUS_RS232;
 548         input_dev->id.vendor = 0x056a;
 549         input_dev->id.version = 0x0100;
 550         input_dev->dev.parent = &serio->dev;
 551
 552         input_dev->open = w8001_open;
 553         input_dev->close = w8001_close;
 554
 555         input_set_drvdata(input_dev, w8001);
 556
 557         err = input_register_device(w8001->dev);
 558         if (err)
 559                 goto fail3;
 560
 561         return 0;
 562
 563 fail3:
 564         serio_close(serio);
 565 fail2:
 566         serio_set_drvdata(serio, NULL);
 567 fail1:
 568         input_free_device(input_dev);
 569         kfree(w8001);
 570         return err;
 571 }
 572
 573 static struct serio_device_id w8001_serio_ids[] = {
 574         {
 575                 .type   = SERIO_RS232,
 576                 .proto  = SERIO_W8001,
 577                 .id     = SERIO_ANY,
 578                 .extra  = SERIO_ANY,
 579         },
 580         { 0 }
 581 };
 582
 583 MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
 584
 585 static struct serio_driver w8001_drv = {
 586         .driver         = {
 587                 .name   = "w8001",
 588         },
 589         .description    = DRIVER_DESC,
 590         .id_table       = w8001_serio_ids,
 591         .interrupt      = w8001_interrupt,
 592         .connect        = w8001_connect,
 593         .disconnect     = w8001_disconnect,
 594 };
 595
 596 module_serio_driver(w8001_drv);