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 struct w8001_coord {
  55         u8 rdy;
  56         u8 tsw;
  57         u8 f1;
  58         u8 f2;
  59         u16 x;
  60         u16 y;
  61         u16 pen_pressure;
  62         u8 tilt_x;
  63         u8 tilt_y;
  64 };
  65
  66 /* touch query reply packet */
  67 struct w8001_touch_query {
  68         u16 x;
  69         u16 y;
  70         u8 panel_res;
  71         u8 capacity_res;
  72         u8 sensor_id;
  73 };
  74
  75 /*
  76  * Per-touchscreen data.
  77  */
  78
  79 struct w8001 {
  80         struct input_dev *dev;
  81         struct serio *serio;
  82         struct completion cmd_done;
  83         int id;
  84         int idx;
  85         unsigned char response_type;
  86         unsigned char response[W8001_MAX_LENGTH];
  87         unsigned char data[W8001_MAX_LENGTH];
  88         char phys[32];
  89         int type;
  90         unsigned int pktlen;
  91         u16 max_touch_x;
  92         u16 max_touch_y;
  93         u16 max_pen_x;
  94         u16 max_pen_y;
  95         char name[64];
  96 };
  97
  98 static void parse_pen_data(u8 *data, struct w8001_coord *coord)
  99 {
 100         memset(coord, 0, sizeof(*coord));
 101
 102         coord->rdy = data[0] & 0x20;
 103         coord->tsw = data[0] & 0x01;
 104         coord->f1 = data[0] & 0x02;
 105         coord->f2 = data[0] & 0x04;
 106
 107         coord->x = (data[1] & 0x7F) << 9;
 108         coord->x |= (data[2] & 0x7F) << 2;
 109         coord->x |= (data[6] & 0x60) >> 5;
 110
 111         coord->y = (data[3] & 0x7F) << 9;
 112         coord->y |= (data[4] & 0x7F) << 2;
 113         coord->y |= (data[6] & 0x18) >> 3;
 114
 115         coord->pen_pressure = data[5] & 0x7F;
 116         coord->pen_pressure |= (data[6] & 0x07) << 7 ;
 117
 118         coord->tilt_x = data[7] & 0x7F;
 119         coord->tilt_y = data[8] & 0x7F;
 120 }
 121
 122 static void parse_single_touch(u8 *data, struct w8001_coord *coord)
 123 {
 124         coord->x = (data[1] << 7) | data[2];
 125         coord->y = (data[3] << 7) | data[4];
 126         coord->tsw = data[0] & 0x01;
 127 }
 128
 129 static void scale_touch_coordinates(struct w8001 *w8001,
 130                                     unsigned int *x, unsigned int *y)
 131 {
 132         if (w8001->max_pen_x && w8001->max_touch_x)
 133                 *x = *x * w8001->max_pen_x / w8001->max_touch_x;
 134
 135         if (w8001->max_pen_y && w8001->max_touch_y)
 136                 *y = *y * w8001->max_pen_y / w8001->max_touch_y;
 137 }
 138
 139 static void parse_multi_touch(struct w8001 *w8001)
 140 {
 141         struct input_dev *dev = w8001->dev;
 142         unsigned char *data = w8001->data;
 143         unsigned int x, y;
 144         int i;
 145         int count = 0;
 146
 147         for (i = 0; i < 2; i++) {
 148                 bool touch = data[0] & (1 << i);
 149
 150                 input_mt_slot(dev, i);
 151                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, touch);
 152                 if (touch) {
 153                         x = (data[6 * i + 1] << 7) | data[6 * i + 2];
 154                         y = (data[6 * i + 3] << 7) | data[6 * i + 4];
 155                         /* data[5,6] and [11,12] is finger capacity */
 156
 157                         /* scale to pen maximum */
 158                         scale_touch_coordinates(w8001, &x, &y);
 159
 160                         input_report_abs(dev, ABS_MT_POSITION_X, x);
 161                         input_report_abs(dev, ABS_MT_POSITION_Y, y);
 162                         count++;
 163                 }
 164         }
 165
 166         /* emulate single touch events when stylus is out of proximity.
 167          * This is to make single touch backward support consistent
 168          * across all Wacom single touch devices.
 169          */
 170         if (w8001->type != BTN_TOOL_PEN &&
 171                             w8001->type != BTN_TOOL_RUBBER) {
 172                 w8001->type = count == 1 ? BTN_TOOL_FINGER : KEY_RESERVED;
 173                 input_mt_report_pointer_emulation(dev, true);
 174         }
 175
 176         input_sync(dev);
 177 }
 178
 179 static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
 180 {
 181         memset(query, 0, sizeof(*query));
 182
 183         query->panel_res = data[1];
 184         query->sensor_id = data[2] & 0x7;
 185         query->capacity_res = data[7];
 186
 187         query->x = data[3] << 9;
 188         query->x |= data[4] << 2;
 189         query->x |= (data[2] >> 5) & 0x3;
 190
 191         query->y = data[5] << 9;
 192         query->y |= data[6] << 2;
 193         query->y |= (data[2] >> 3) & 0x3;
 194
 195         /* Early days' single-finger touch models need the following defaults */
 196         if (!query->x && !query->y) {
 197                 query->x = 1024;
 198                 query->y = 1024;
 199                 if (query->panel_res)
 200                         query->x = query->y = (1 << query->panel_res);
 201                 query->panel_res = 10;
 202         }
 203 }
 204
 205 static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
 206 {
 207         struct input_dev *dev = w8001->dev;
 208
 209         /*
 210          * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
 211          * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
 212          * or eraser. Assume:
 213          * - if dev is already in proximity and f2 is toggled → pen + side2
 214          * - if dev comes into proximity with f2 set → eraser
 215          * If f2 disappears after assuming eraser, fake proximity out for
 216          * eraser and in for pen.
 217          */
 218
 219         switch (w8001->type) {
 220         case BTN_TOOL_RUBBER:
 221                 if (!coord->f2) {
 222                         input_report_abs(dev, ABS_PRESSURE, 0);
 223                         input_report_key(dev, BTN_TOUCH, 0);
 224                         input_report_key(dev, BTN_STYLUS, 0);
 225                         input_report_key(dev, BTN_STYLUS2, 0);
 226                         input_report_key(dev, BTN_TOOL_RUBBER, 0);
 227                         input_sync(dev);
 228                         w8001->type = BTN_TOOL_PEN;
 229                 }
 230                 break;
 231
 232         case BTN_TOOL_FINGER:
 233                 input_report_key(dev, BTN_TOUCH, 0);
 234                 input_report_key(dev, BTN_TOOL_FINGER, 0);
 235                 input_sync(dev);
 236                 /* fall through */
 237
 238         case KEY_RESERVED:
 239                 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
 240                 break;
 241
 242         default:
 243                 input_report_key(dev, BTN_STYLUS2, coord->f2);
 244                 break;
 245         }
 246
 247         input_report_abs(dev, ABS_X, coord->x);
 248         input_report_abs(dev, ABS_Y, coord->y);
 249         input_report_abs(dev, ABS_PRESSURE, coord->pen_pressure);
 250         input_report_key(dev, BTN_TOUCH, coord->tsw);
 251         input_report_key(dev, BTN_STYLUS, coord->f1);
 252         input_report_key(dev, w8001->type, coord->rdy);
 253         input_sync(dev);
 254
 255         if (!coord->rdy)
 256                 w8001->type = KEY_RESERVED;
 257 }
 258
 259 static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord)
 260 {
 261         struct input_dev *dev = w8001->dev;
 262         unsigned int x = coord->x;
 263         unsigned int y = coord->y;
 264
 265         /* scale to pen maximum */
 266         scale_touch_coordinates(w8001, &x, &y);
 267
 268         input_report_abs(dev, ABS_X, x);
 269         input_report_abs(dev, ABS_Y, y);
 270         input_report_key(dev, BTN_TOUCH, coord->tsw);
 271         input_report_key(dev, BTN_TOOL_FINGER, coord->tsw);
 272
 273         input_sync(dev);
 274
 275         w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED;
 276 }
 277
 278 static irqreturn_t w8001_interrupt(struct serio *serio,
 279                                    unsigned char data, unsigned int flags)
 280 {
 281         struct w8001 *w8001 = serio_get_drvdata(serio);
 282         struct w8001_coord coord;
 283         unsigned char tmp;
 284
 285         w8001->data[w8001->idx] = data;
 286         switch (w8001->idx++) {
 287         case 0:
 288                 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
 289                         pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
 290                         w8001->idx = 0;
 291                 }
 292                 break;
 293
 294         case W8001_PKTLEN_TOUCH93 - 1:
 295         case W8001_PKTLEN_TOUCH9A - 1:
 296                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
 297                 if (tmp != W8001_TOUCH_BYTE)
 298                         break;
 299
 300                 if (w8001->pktlen == w8001->idx) {
 301                         w8001->idx = 0;
 302                         if (w8001->type != BTN_TOOL_PEN &&
 303                             w8001->type != BTN_TOOL_RUBBER) {
 304                                 parse_single_touch(w8001->data, &coord);
 305                                 report_single_touch(w8001, &coord);
 306                         }
 307                 }
 308                 break;
 309
 310         /* Pen coordinates packet */
 311         case W8001_PKTLEN_TPCPEN - 1:
 312                 tmp = w8001->data[0] & W8001_TAB_MASK;
 313                 if (unlikely(tmp == W8001_TAB_BYTE))
 314                         break;
 315
 316                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
 317                 if (tmp == W8001_TOUCH_BYTE)
 318                         break;
 319
 320                 w8001->idx = 0;
 321                 parse_pen_data(w8001->data, &coord);
 322                 report_pen_events(w8001, &coord);
 323                 break;
 324
 325         /* control packet */
 326         case W8001_PKTLEN_TPCCTL - 1:
 327                 tmp = w8001->data[0] & W8001_TOUCH_MASK;
 328                 if (tmp == W8001_TOUCH_BYTE)
 329                         break;
 330
 331                 w8001->idx = 0;
 332                 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
 333                 w8001->response_type = W8001_QUERY_PACKET;
 334                 complete(&w8001->cmd_done);
 335                 break;
 336
 337         /* 2 finger touch packet */
 338         case W8001_PKTLEN_TOUCH2FG - 1:
 339                 w8001->idx = 0;
 340                 parse_multi_touch(w8001);
 341                 break;
 342         }
 343
 344         return IRQ_HANDLED;
 345 }
 346
 347 static int w8001_command(struct w8001 *w8001, unsigned char command,
 348                          bool wait_response)
 349 {
 350         int rc;
 351
 352         w8001->response_type = 0;
 353         init_completion(&w8001->cmd_done);
 354
 355         rc = serio_write(w8001->serio, command);
 356         if (rc == 0 && wait_response) {
 357
 358                 wait_for_completion_timeout(&w8001->cmd_done, HZ);
 359                 if (w8001->response_type != W8001_QUERY_PACKET)
 360                         rc = -EIO;
 361         }
 362
 363         return rc;
 364 }
 365
 366 static int w8001_setup(struct w8001 *w8001)
 367 {
 368         struct input_dev *dev = w8001->dev;
 369         struct w8001_coord coord;
 370         struct w8001_touch_query touch;
 371         int error;
 372
 373         error = w8001_command(w8001, W8001_CMD_STOP, false);
 374         if (error)
 375                 return error;
 376
 377         msleep(250);    /* wait 250ms before querying the device */
 378
 379         dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 380         strlcat(w8001->name, "Wacom Serial", sizeof(w8001->name));
 381
 382         /* penabled? */
 383         error = w8001_command(w8001, W8001_CMD_QUERY, true);
 384         if (!error) {
 385                 __set_bit(BTN_TOUCH, dev->keybit);
 386                 __set_bit(BTN_TOOL_PEN, dev->keybit);
 387                 __set_bit(BTN_TOOL_RUBBER, dev->keybit);
 388                 __set_bit(BTN_STYLUS, dev->keybit);
 389                 __set_bit(BTN_STYLUS2, dev->keybit);
 390
 391                 parse_pen_data(w8001->response, &coord);
 392                 w8001->max_pen_x = coord.x;
 393                 w8001->max_pen_y = coord.y;
 394
 395                 input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
 396                 input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
 397                 input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
 398                 if (coord.tilt_x && coord.tilt_y) {
 399                         input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
 400                         input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
 401                 }
 402                 w8001->id = 0x90;
 403                 strlcat(w8001->name, " Penabled", sizeof(w8001->name));
 404         }
 405
 406         /* Touch enabled? */
 407         error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
 408
 409         /*
 410          * Some non-touch devices may reply to the touch query. But their
 411          * second byte is empty, which indicates touch is not supported.
 412          */
 413         if (!error && w8001->response[1]) {
 414                 __set_bit(BTN_TOUCH, dev->keybit);
 415                 __set_bit(BTN_TOOL_FINGER, dev->keybit);
 416
 417                 parse_touchquery(w8001->response, &touch);
 418                 w8001->max_touch_x = touch.x;
 419                 w8001->max_touch_y = touch.y;
 420
 421                 /* scale to pen maximum */
 422                 if (w8001->max_pen_x && w8001->max_pen_y) {
 423                         touch.x = w8001->max_pen_x;
 424                         touch.y = w8001->max_pen_y;
 425                 }
 426
 427                 input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
 428                 input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
 429
 430                 switch (touch.sensor_id) {
 431                 case 0:
 432                 case 2:
 433                         w8001->pktlen = W8001_PKTLEN_TOUCH93;
 434                         w8001->id = 0x93;
 435                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
 436                         break;
 437
 438                 case 1:
 439                 case 3:
 440                 case 4:
 441                         w8001->pktlen = W8001_PKTLEN_TOUCH9A;
 442                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
 443                         w8001->id = 0x9a;
 444                         break;
 445
 446                 case 5:
 447                         w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
 448
 449                         input_mt_init_slots(dev, 2);
 450                         input_set_abs_params(dev, ABS_MT_POSITION_X,
 451                                                 0, touch.x, 0, 0);
 452                         input_set_abs_params(dev, ABS_MT_POSITION_Y,
 453                                                 0, touch.y, 0, 0);
 454                         input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
 455                                                 0, MT_TOOL_MAX, 0, 0);
 456
 457                         strlcat(w8001->name, " 2FG", sizeof(w8001->name));
 458                         if (w8001->max_pen_x && w8001->max_pen_y)
 459                                 w8001->id = 0xE3;
 460                         else
 461                                 w8001->id = 0xE2;
 462                         break;
 463                 }
 464         }
 465
 466         strlcat(w8001->name, " Touchscreen", sizeof(w8001->name));
 467
 468         return w8001_command(w8001, W8001_CMD_START, false);
 469 }
 470
 471 /*
 472  * w8001_disconnect() is the opposite of w8001_connect()
 473  */
 474
 475 static void w8001_disconnect(struct serio *serio)
 476 {
 477         struct w8001 *w8001 = serio_get_drvdata(serio);
 478
 479         input_get_device(w8001->dev);
 480         input_unregister_device(w8001->dev);
 481         serio_close(serio);
 482         serio_set_drvdata(serio, NULL);
 483         input_put_device(w8001->dev);
 484         kfree(w8001);
 485 }
 486
 487 /*
 488  * w8001_connect() is the routine that is called when someone adds a
 489  * new serio device that supports the w8001 protocol and registers it as
 490  * an input device.
 491  */
 492
 493 static int w8001_connect(struct serio *serio, struct serio_driver *drv)
 494 {
 495         struct w8001 *w8001;
 496         struct input_dev *input_dev;
 497         int err;
 498
 499         w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
 500         input_dev = input_allocate_device();
 501         if (!w8001 || !input_dev) {
 502                 err = -ENOMEM;
 503                 goto fail1;
 504         }
 505
 506         w8001->serio = serio;
 507         w8001->dev = input_dev;
 508         init_completion(&w8001->cmd_done);
 509         snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
 510
 511         serio_set_drvdata(serio, w8001);
 512         err = serio_open(serio, drv);
 513         if (err)
 514                 goto fail2;
 515
 516         err = w8001_setup(w8001);
 517         if (err)
 518                 goto fail3;
 519
 520         input_dev->name = w8001->name;
 521         input_dev->phys = w8001->phys;
 522         input_dev->id.product = w8001->id;
 523         input_dev->id.bustype = BUS_RS232;
 524         input_dev->id.vendor = 0x056a;
 525         input_dev->id.version = 0x0100;
 526         input_dev->dev.parent = &serio->dev;
 527
 528         err = input_register_device(w8001->dev);
 529         if (err)
 530                 goto fail3;
 531
 532         return 0;
 533
 534 fail3:
 535         serio_close(serio);
 536 fail2:
 537         serio_set_drvdata(serio, NULL);
 538 fail1:
 539         input_free_device(input_dev);
 540         kfree(w8001);
 541         return err;
 542 }
 543
 544 static struct serio_device_id w8001_serio_ids[] = {
 545         {
 546                 .type   = SERIO_RS232,
 547                 .proto  = SERIO_W8001,
 548                 .id     = SERIO_ANY,
 549                 .extra  = SERIO_ANY,
 550         },
 551         { 0 }
 552 };
 553
 554 MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
 555
 556 static struct serio_driver w8001_drv = {
 557         .driver         = {
 558                 .name   = "w8001",
 559         },
 560         .description    = DRIVER_DESC,
 561         .id_table       = w8001_serio_ids,
 562         .interrupt      = w8001_interrupt,
 563         .connect        = w8001_connect,
 564         .disconnect     = w8001_disconnect,
 565 };
 566
 567 static int __init w8001_init(void)
 568 {
 569         return serio_register_driver(&w8001_drv);
 570 }
 571
 572 static void __exit w8001_exit(void)
 573 {
 574         serio_unregister_driver(&w8001_drv);
 575 }
 576
 577 module_init(w8001_init);
 578 module_exit(w8001_exit);