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  *
   7  * This file is subject to the terms and conditions of the GNU General Public
   8  * License. See the file COPYING in the main directory of this archive for
   9  * more details.
  10  *
  11  * Layout based on Elo serial touchscreen driver by Vojtech Pavlik
  12  */
  13
  14 #include <linux/errno.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/input.h>
  19 #include <linux/serio.h>
  20 #include <linux/init.h>
  21 #include <linux/ctype.h>
  22
  23 #define DRIVER_DESC     "Wacom W8001 serial touchscreen driver"
  24
  25 MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
  26 MODULE_DESCRIPTION(DRIVER_DESC);
  27 MODULE_LICENSE("GPL");
  28
  29 #define W8001_MAX_LENGTH        11
  30 #define W8001_LEAD_MASK         0x80
  31 #define W8001_LEAD_BYTE         0x80
  32 #define W8001_TAB_MASK          0x40
  33 #define W8001_TAB_BYTE          0x40
  34 /* set in first byte of touch data packets */
  35 #define W8001_TOUCH_MASK        (0x10 | W8001_LEAD_MASK)
  36 #define W8001_TOUCH_BYTE        (0x10 | W8001_LEAD_BYTE)
  37
  38 #define W8001_QUERY_PACKET      0x20
  39
  40 #define W8001_CMD_START         '1'
  41 #define W8001_CMD_QUERY         '*'
  42 #define W8001_CMD_TOUCHQUERY    '%'
  43
  44 /* length of data packets in bytes, depends on device. */
  45 #define W8001_PKTLEN_TOUCH93    5
  46 #define W8001_PKTLEN_TOUCH9A    7
  47 #define W8001_PKTLEN_TPCPEN     9
  48 #define W8001_PKTLEN_TPCCTL     11      /* control packet */
  49 #define W8001_PKTLEN_TOUCH2FG   13
  50
  51 #define MAX_TRACKING_ID         0xFF    /* arbitrarily chosen */
  52
  53 struct w8001_coord {
  54         u8 rdy;
  55         u8 tsw;
  56         u8 f1;
  57         u8 f2;
  58         u16 x;
  59         u16 y;
  60         u16 pen_pressure;
  61         u8 tilt_x;
  62         u8 tilt_y;
  63 };
  64
  65 /* touch query reply packet */
  66 struct w8001_touch_query {
  67         u8 panel_res;
  68         u8 capacity_res;
  69         u8 sensor_id;
  70         u16 x;
  71         u16 y;
  72 };
  73
  74 /*
  75  * Per-touchscreen data.
  76  */
  77
  78 struct w8001 {
  79         struct input_dev *dev;
  80         struct serio *serio;
  81         struct completion cmd_done;
  82         int id;
  83         int idx;
  84         unsigned char response_type;
  85         unsigned char response[W8001_MAX_LENGTH];
  86         unsigned char data[W8001_MAX_LENGTH];
  87         char phys[32];
  88         int type;
  89         unsigned int pktlen;
  90         int trkid[2];
  91 };
  92
  93 static void parse_data(u8 *data, struct w8001_coord *coord)
  94 {
  95         memset(coord, 0, sizeof(*coord));
  96
  97         coord->rdy = data[0] & 0x20;
  98         coord->tsw = data[0] & 0x01;
  99         coord->f1 = data[0] & 0x02;
 100         coord->f2 = data[0] & 0x04;
 101
 102         coord->x = (data[1] & 0x7F) << 9;
 103         coord->x |= (data[2] & 0x7F) << 2;
 104         coord->x |= (data[6] & 0x60) >> 5;
 105
 106         coord->y = (data[3] & 0x7F) << 9;
 107         coord->y |= (data[4] & 0x7F) << 2;
 108         coord->y |= (data[6] & 0x18) >> 3;
 109
 110         coord->pen_pressure = data[5] & 0x7F;
 111         coord->pen_pressure |= (data[6] & 0x07) << 7 ;
 112
 113         coord->tilt_x = data[7] & 0x7F;
 114         coord->tilt_y = data[8] & 0x7F;
 115 }
 116
 117 static void parse_touch(struct w8001 *w8001)
 118 {
 119         static int trkid;
 120         struct input_dev *dev = w8001->dev;
 121         unsigned char *data = w8001->data;
 122         int i;
 123
 124         for (i = 0; i < 2; i++) {
 125                 input_mt_slot(dev, i);
 126
 127                 if (data[0] & (1 << i)) {
 128                         int x = (data[6 * i + 1] << 7) | (data[6 * i + 2]);
 129                         int y = (data[6 * i + 3] << 7) | (data[6 * i + 4]);
 130                         /* data[5,6] and [11,12] is finger capacity */
 131
 132                         input_report_abs(dev, ABS_MT_POSITION_X, x);
 133                         input_report_abs(dev, ABS_MT_POSITION_Y, y);
 134                         input_report_abs(dev, ABS_MT_TOOL_TYPE, MT_TOOL_FINGER);
 135                         if (w8001->trkid[i] < 0)
 136                                 w8001->trkid[i] = trkid++ & MAX_TRACKING_ID;
 137                 } else {
 138                         w8001->trkid[i] = -1;
 139                 }
 140                 input_report_abs(dev, ABS_MT_TRACKING_ID, w8001->trkid[i]);
 141         }
 142
 143         input_sync(dev);
 144 }
 145
 146 static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
 147 {
 148         memset(query, 0, sizeof(*query));
 149
 150         query->panel_res = data[1];
 151         query->sensor_id = data[2] & 0x7;
 152         query->capacity_res = data[7];
 153
 154         query->x = data[3] << 9;
 155         query->x |= data[4] << 2;
 156         query->x |= (data[2] >> 5) & 0x3;
 157
 158         query->y = data[5] << 9;
 159         query->y |= data[6] << 2;
 160         query->y |= (data[2] >> 3) & 0x3;
 161 }
 162
 163 static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
 164 {
 165         struct input_dev *dev = w8001->dev;
 166
 167         /*
 168          * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
 169          * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
 170          * or eraser. assume
 171          * - if dev is already in proximity and f2 is toggled → pen + side2
 172          * - if dev comes into proximity with f2 set → eraser
 173          * If f2 disappears after assuming eraser, fake proximity out for
 174          * eraser and in for pen.
 175          */
 176
 177         if (!w8001->type) {
 178                 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
 179         } else if (w8001->type == BTN_TOOL_RUBBER) {
 180                 if (!coord->f2) {
 181                         input_report_abs(dev, ABS_PRESSURE, 0);
 182                         input_report_key(dev, BTN_TOUCH, 0);
 183                         input_report_key(dev, BTN_STYLUS, 0);
 184                         input_report_key(dev, BTN_STYLUS2, 0);
 185                         input_report_key(dev, BTN_TOOL_RUBBER, 0);
 186                         input_sync(dev);
 187                         w8001->type = BTN_TOOL_PEN;
 188                 }
 189         } else {
 190                 input_report_key(dev, BTN_STYLUS2, coord->f2);
 191         }
 192
 193         input_report_abs(dev, ABS_X, coord->x);
 194         input_report_abs(dev, ABS_Y, coord->y);
 195         input_report_abs(dev, ABS_PRESSURE, coord->pen_pressure);
 196         input_report_key(dev, BTN_TOUCH, coord->tsw);
 197         input_report_key(dev, BTN_STYLUS, coord->f1);
 198         input_report_key(dev, w8001->type, coord->rdy);
 199         input_sync(dev);
 200
 201         if (!coord->rdy)
 202                 w8001->type = 0;
 203 }
 204
 205 static irqreturn_t w8001_interrupt(struct serio *serio,
 206                                    unsigned char data, unsigned int flags)
 207 {
 208         struct w8001 *w8001 = serio_get_drvdata(serio);
 209         struct w8001_coord coord;
 210         unsigned char tmp;
 211
 212         w8001->data[w8001->idx] = data;
 213         switch (w8001->idx++) {
 214         case 0:
 215                 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
 216                         pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
 217                         w8001->idx = 0;
 218                 }
 219                 break;
 220
 221         case W8001_PKTLEN_TOUCH93 - 1:
 222         case W8001_PKTLEN_TOUCH9A - 1:
 223                 /* ignore one-finger touch packet. */
 224                 if (w8001->pktlen == w8001->idx)
 225                         w8001->idx = 0;
 226                 break;
 227
 228         /* Pen coordinates packet */
 229         case W8001_PKTLEN_TPCPEN - 1:
 230                 tmp = w8001->data[0] & W8001_TAB_MASK;
 231                 if (unlikely(tmp == W8001_TAB_BYTE))
 232                         break;
 233
 234                 tmp = (w8001->data[0] & W8001_TOUCH_BYTE);
 235                 if (tmp == W8001_TOUCH_BYTE)
 236                         break;
 237
 238                 w8001->idx = 0;
 239                 parse_data(w8001->data, &coord);
 240                 report_pen_events(w8001, &coord);
 241                 break;
 242
 243         /* control packet */
 244         case W8001_PKTLEN_TPCCTL - 1:
 245                 tmp = (w8001->data[0] & W8001_TOUCH_MASK);
 246                 if (tmp == W8001_TOUCH_BYTE)
 247                         break;
 248
 249                 w8001->idx = 0;
 250                 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
 251                 w8001->response_type = W8001_QUERY_PACKET;
 252                 complete(&w8001->cmd_done);
 253                 break;
 254
 255         /* 2 finger touch packet */
 256         case W8001_PKTLEN_TOUCH2FG - 1:
 257                 w8001->idx = 0;
 258                 parse_touch(w8001);
 259                 break;
 260         }
 261
 262         return IRQ_HANDLED;
 263 }
 264
 265 static int w8001_command(struct w8001 *w8001, unsigned char command,
 266                          bool wait_response)
 267 {
 268         int rc;
 269
 270         w8001->response_type = 0;
 271         init_completion(&w8001->cmd_done);
 272
 273         rc = serio_write(w8001->serio, command);
 274         if (rc == 0 && wait_response) {
 275
 276                 wait_for_completion_timeout(&w8001->cmd_done, HZ);
 277                 if (w8001->response_type != W8001_QUERY_PACKET)
 278                         rc = -EIO;
 279         }
 280
 281         return rc;
 282 }
 283
 284 static int w8001_setup(struct w8001 *w8001)
 285 {
 286         struct input_dev *dev = w8001->dev;
 287         struct w8001_coord coord;
 288         int error;
 289
 290         error = w8001_command(w8001, W8001_CMD_QUERY, true);
 291         if (error)
 292                 return error;
 293
 294         parse_data(w8001->response, &coord);
 295
 296         input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
 297         input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
 298         input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
 299         input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
 300         input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
 301
 302         error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
 303         if (!error) {
 304                 struct w8001_touch_query touch;
 305
 306                 parse_touchquery(w8001->response, &touch);
 307
 308                 switch (touch.sensor_id) {
 309                 case 0:
 310                 case 2:
 311                         w8001->pktlen = W8001_PKTLEN_TOUCH93;
 312                         break;
 313                 case 1:
 314                 case 3:
 315                 case 4:
 316                         w8001->pktlen = W8001_PKTLEN_TOUCH9A;
 317                         break;
 318                 case 5:
 319                         w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
 320
 321                         input_mt_create_slots(dev, 2);
 322                         input_set_abs_params(dev, ABS_MT_TRACKING_ID,
 323                                                 0, MAX_TRACKING_ID, 0, 0);
 324                         input_set_abs_params(dev, ABS_MT_POSITION_X,
 325                                                 0, touch.x, 0, 0);
 326                         input_set_abs_params(dev, ABS_MT_POSITION_Y,
 327                                                 0, touch.y, 0, 0);
 328                         input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
 329                                                 0, 0, 0, 0);
 330                         break;
 331                 }
 332         }
 333
 334         return w8001_command(w8001, W8001_CMD_START, false);
 335 }
 336
 337 /*
 338  * w8001_disconnect() is the opposite of w8001_connect()
 339  */
 340
 341 static void w8001_disconnect(struct serio *serio)
 342 {
 343         struct w8001 *w8001 = serio_get_drvdata(serio);
 344
 345         input_get_device(w8001->dev);
 346         input_unregister_device(w8001->dev);
 347         serio_close(serio);
 348         serio_set_drvdata(serio, NULL);
 349         input_put_device(w8001->dev);
 350         kfree(w8001);
 351 }
 352
 353 /*
 354  * w8001_connect() is the routine that is called when someone adds a
 355  * new serio device that supports the w8001 protocol and registers it as
 356  * an input device.
 357  */
 358
 359 static int w8001_connect(struct serio *serio, struct serio_driver *drv)
 360 {
 361         struct w8001 *w8001;
 362         struct input_dev *input_dev;
 363         int err;
 364
 365         w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
 366         input_dev = input_allocate_device();
 367         if (!w8001 || !input_dev) {
 368                 err = -ENOMEM;
 369                 goto fail1;
 370         }
 371
 372         w8001->serio = serio;
 373         w8001->id = serio->id.id;
 374         w8001->dev = input_dev;
 375         w8001->trkid[0] = w8001->trkid[1] = -1;
 376         init_completion(&w8001->cmd_done);
 377         snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
 378
 379         input_dev->name = "Wacom W8001 Penabled Serial TouchScreen";
 380         input_dev->phys = w8001->phys;
 381         input_dev->id.bustype = BUS_RS232;
 382         input_dev->id.vendor = SERIO_W8001;
 383         input_dev->id.product = w8001->id;
 384         input_dev->id.version = 0x0100;
 385         input_dev->dev.parent = &serio->dev;
 386
 387         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 388         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 389         input_dev->keybit[BIT_WORD(BTN_TOOL_PEN)] |= BIT_MASK(BTN_TOOL_PEN);
 390         input_dev->keybit[BIT_WORD(BTN_TOOL_RUBBER)] |= BIT_MASK(BTN_TOOL_RUBBER);
 391         input_dev->keybit[BIT_WORD(BTN_STYLUS)] |= BIT_MASK(BTN_STYLUS);
 392         input_dev->keybit[BIT_WORD(BTN_STYLUS2)] |= BIT_MASK(BTN_STYLUS2);
 393
 394         serio_set_drvdata(serio, w8001);
 395         err = serio_open(serio, drv);
 396         if (err)
 397                 goto fail2;
 398
 399         err = w8001_setup(w8001);
 400         if (err)
 401                 goto fail3;
 402
 403         err = input_register_device(w8001->dev);
 404         if (err)
 405                 goto fail3;
 406
 407         return 0;
 408
 409 fail3:
 410         serio_close(serio);
 411 fail2:
 412         serio_set_drvdata(serio, NULL);
 413 fail1:
 414         input_free_device(input_dev);
 415         kfree(w8001);
 416         return err;
 417 }
 418
 419 static struct serio_device_id w8001_serio_ids[] = {
 420         {
 421                 .type   = SERIO_RS232,
 422                 .proto  = SERIO_W8001,
 423                 .id     = SERIO_ANY,
 424                 .extra  = SERIO_ANY,
 425         },
 426         { 0 }
 427 };
 428
 429 MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
 430
 431 static struct serio_driver w8001_drv = {
 432         .driver         = {
 433                 .name   = "w8001",
 434         },
 435         .description    = DRIVER_DESC,
 436         .id_table       = w8001_serio_ids,
 437         .interrupt      = w8001_interrupt,
 438         .connect        = w8001_connect,
 439         .disconnect     = w8001_disconnect,
 440 };
 441
 442 static int __init w8001_init(void)
 443 {
 444         return serio_register_driver(&w8001_drv);
 445 }
 446
 447 static void __exit w8001_exit(void)
 448 {
 449         serio_unregister_driver(&w8001_drv);
 450 }
 451
 452 module_init(w8001_init);
 453 module_exit(w8001_exit);