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