drivers/input/touchscreen/elo.c

   1 /*
   2  * Elo serial touchscreen driver
   3  *
   4  * Copyright (c) 2004 Vojtech Pavlik
   5  */
   6
   7 /*
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License version 2 as published by
  10  * the Free Software Foundation.
  11  */
  12
  13 /*
  14  * This driver can handle serial Elo touchscreens using either the Elo standard
  15  * 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo
  16  * legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol.
  17  */
  18
  19 #include <linux/errno.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/slab.h>
  23 #include <linux/input.h>
  24 #include <linux/serio.h>
  25 #include <linux/init.h>
  26 #include <linux/ctype.h>
  27
  28 #define DRIVER_DESC     "Elo serial touchscreen driver"
  29
  30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  31 MODULE_DESCRIPTION(DRIVER_DESC);
  32 MODULE_LICENSE("GPL");
  33
  34 /*
  35  * Definitions & global arrays.
  36  */
  37
  38 #define ELO_MAX_LENGTH          10
  39
  40 #define ELO10_PACKET_LEN        8
  41 #define ELO10_TOUCH             0x03
  42 #define ELO10_PRESSURE          0x80
  43
  44 #define ELO10_LEAD_BYTE         'U'
  45
  46 #define ELO10_ID_CMD            'i'
  47
  48 #define ELO10_TOUCH_PACKET      'T'
  49 #define ELO10_ACK_PACKET        'A'
  50 #define ELI10_ID_PACKET         'I'
  51
  52 /*
  53  * Per-touchscreen data.
  54  */
  55
  56 struct elo {
  57         struct input_dev *dev;
  58         struct serio *serio;
  59         struct mutex cmd_mutex;
  60         struct completion cmd_done;
  61         int id;
  62         int idx;
  63         unsigned char expected_packet;
  64         unsigned char csum;
  65         unsigned char data[ELO_MAX_LENGTH];
  66         unsigned char response[ELO10_PACKET_LEN];
  67         char phys[32];
  68 };
  69
  70 static void elo_process_data_10(struct elo *elo, unsigned char data)
  71 {
  72         struct input_dev *dev = elo->dev;
  73
  74         elo->data[elo->idx] = data;
  75
  76         switch (elo->idx++) {
  77         case 0:
  78                 elo->csum = 0xaa;
  79                 if (data != ELO10_LEAD_BYTE) {
  80                         dev_dbg(&elo->serio->dev,
  81                                 "unsynchronized data: 0x%02x\n", data);
  82                         elo->idx = 0;
  83                 }
  84                 break;
  85
  86         case 9:
  87                 elo->idx = 0;
  88                 if (data != elo->csum) {
  89                         dev_dbg(&elo->serio->dev,
  90                                 "bad checksum: 0x%02x, expected 0x%02x\n",
  91                                  data, elo->csum);
  92                         break;
  93                 }
  94                 if (elo->data[1] != elo->expected_packet) {
  95                         if (elo->data[1] != ELO10_TOUCH_PACKET)
  96                                 dev_dbg(&elo->serio->dev,
  97                                         "unexpected packet: 0x%02x\n",
  98                                          elo->data[1]);
  99                         break;
 100                 }
 101                 if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
 102                         input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
 103                         input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
 104                         if (elo->data[2] & ELO10_PRESSURE)
 105                                 input_report_abs(dev, ABS_PRESSURE,
 106                                                 (elo->data[8] << 8) | elo->data[7]);
 107                         input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
 108                         input_sync(dev);
 109                 } else if (elo->data[1] == ELO10_ACK_PACKET) {
 110                         if (elo->data[2] == '0')
 111                                 elo->expected_packet = ELO10_TOUCH_PACKET;
 112                         complete(&elo->cmd_done);
 113                 } else {
 114                         memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
 115                         elo->expected_packet = ELO10_ACK_PACKET;
 116                 }
 117                 break;
 118         }
 119         elo->csum += data;
 120 }
 121
 122 static void elo_process_data_6(struct elo *elo, unsigned char data)
 123 {
 124         struct input_dev *dev = elo->dev;
 125
 126         elo->data[elo->idx] = data;
 127
 128         switch (elo->idx++) {
 129
 130         case 0:
 131                 if ((data & 0xc0) != 0xc0)
 132                         elo->idx = 0;
 133                 break;
 134
 135         case 1:
 136                 if ((data & 0xc0) != 0x80)
 137                         elo->idx = 0;
 138                 break;
 139
 140         case 2:
 141                 if ((data & 0xc0) != 0x40)
 142                         elo->idx = 0;
 143                 break;
 144
 145         case 3:
 146                 if (data & 0xc0) {
 147                         elo->idx = 0;
 148                         break;
 149                 }
 150
 151                 input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
 152                 input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
 153
 154                 if (elo->id == 2) {
 155                         input_report_key(dev, BTN_TOUCH, 1);
 156                         input_sync(dev);
 157                         elo->idx = 0;
 158                 }
 159
 160                 break;
 161
 162         case 4:
 163                 if (data) {
 164                         input_sync(dev);
 165                         elo->idx = 0;
 166                 }
 167                 break;
 168
 169         case 5:
 170                 if ((data & 0xf0) == 0) {
 171                         input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
 172                         input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
 173                 }
 174                 input_sync(dev);
 175                 elo->idx = 0;
 176                 break;
 177         }
 178 }
 179
 180 static void elo_process_data_3(struct elo *elo, unsigned char data)
 181 {
 182         struct input_dev *dev = elo->dev;
 183
 184         elo->data[elo->idx] = data;
 185
 186         switch (elo->idx++) {
 187
 188         case 0:
 189                 if ((data & 0x7f) != 0x01)
 190                         elo->idx = 0;
 191                 break;
 192         case 2:
 193                 input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
 194                 input_report_abs(dev, ABS_X, elo->data[1]);
 195                 input_report_abs(dev, ABS_Y, elo->data[2]);
 196                 input_sync(dev);
 197                 elo->idx = 0;
 198                 break;
 199         }
 200 }
 201
 202 static irqreturn_t elo_interrupt(struct serio *serio,
 203                 unsigned char data, unsigned int flags)
 204 {
 205         struct elo *elo = serio_get_drvdata(serio);
 206
 207         switch (elo->id) {
 208         case 0:
 209                 elo_process_data_10(elo, data);
 210                 break;
 211
 212         case 1:
 213         case 2:
 214                 elo_process_data_6(elo, data);
 215                 break;
 216
 217         case 3:
 218                 elo_process_data_3(elo, data);
 219                 break;
 220         }
 221
 222         return IRQ_HANDLED;
 223 }
 224
 225 static int elo_command_10(struct elo *elo, unsigned char *packet)
 226 {
 227         int rc = -1;
 228         int i;
 229         unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
 230
 231         mutex_lock(&elo->cmd_mutex);
 232
 233         serio_pause_rx(elo->serio);
 234         elo->expected_packet = toupper(packet[0]);
 235         init_completion(&elo->cmd_done);
 236         serio_continue_rx(elo->serio);
 237
 238         if (serio_write(elo->serio, ELO10_LEAD_BYTE))
 239                 goto out;
 240
 241         for (i = 0; i < ELO10_PACKET_LEN; i++) {
 242                 csum += packet[i];
 243                 if (serio_write(elo->serio, packet[i]))
 244                         goto out;
 245         }
 246
 247         if (serio_write(elo->serio, csum))
 248                 goto out;
 249
 250         wait_for_completion_timeout(&elo->cmd_done, HZ);
 251
 252         if (elo->expected_packet == ELO10_TOUCH_PACKET) {
 253                 /* We are back in reporting mode, the command was ACKed */
 254                 memcpy(packet, elo->response, ELO10_PACKET_LEN);
 255                 rc = 0;
 256         }
 257
 258  out:
 259         mutex_unlock(&elo->cmd_mutex);
 260         return rc;
 261 }
 262
 263 static int elo_setup_10(struct elo *elo)
 264 {
 265         static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
 266         struct input_dev *dev = elo->dev;
 267         unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
 268
 269         if (elo_command_10(elo, packet))
 270                 return -1;
 271
 272         dev->id.version = (packet[5] << 8) | packet[4];
 273
 274         input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
 275         input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
 276         if (packet[3] & ELO10_PRESSURE)
 277                 input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
 278
 279         dev_info(&elo->serio->dev,
 280                  "%sTouch touchscreen, fw: %02x.%02x, features: 0x%02x, controller: 0x%02x\n",
 281                  elo_types[(packet[1] -'0') & 0x03],
 282                  packet[5], packet[4], packet[3], packet[7]);
 283
 284         return 0;
 285 }
 286
 287 /*
 288  * elo_disconnect() is the opposite of elo_connect()
 289  */
 290
 291 static void elo_disconnect(struct serio *serio)
 292 {
 293         struct elo *elo = serio_get_drvdata(serio);
 294
 295         input_get_device(elo->dev);
 296         input_unregister_device(elo->dev);
 297         serio_close(serio);
 298         serio_set_drvdata(serio, NULL);
 299         input_put_device(elo->dev);
 300         kfree(elo);
 301 }
 302
 303 /*
 304  * elo_connect() is the routine that is called when someone adds a
 305  * new serio device that supports Gunze protocol and registers it as
 306  * an input device.
 307  */
 308
 309 static int elo_connect(struct serio *serio, struct serio_driver *drv)
 310 {
 311         struct elo *elo;
 312         struct input_dev *input_dev;
 313         int err;
 314
 315         elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
 316         input_dev = input_allocate_device();
 317         if (!elo || !input_dev) {
 318                 err = -ENOMEM;
 319                 goto fail1;
 320         }
 321
 322         elo->serio = serio;
 323         elo->id = serio->id.id;
 324         elo->dev = input_dev;
 325         elo->expected_packet = ELO10_TOUCH_PACKET;
 326         mutex_init(&elo->cmd_mutex);
 327         init_completion(&elo->cmd_done);
 328         snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
 329
 330         input_dev->name = "Elo Serial TouchScreen";
 331         input_dev->phys = elo->phys;
 332         input_dev->id.bustype = BUS_RS232;
 333         input_dev->id.vendor = SERIO_ELO;
 334         input_dev->id.product = elo->id;
 335         input_dev->id.version = 0x0100;
 336         input_dev->dev.parent = &serio->dev;
 337
 338         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 339         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 340
 341         serio_set_drvdata(serio, elo);
 342         err = serio_open(serio, drv);
 343         if (err)
 344                 goto fail2;
 345
 346         switch (elo->id) {
 347
 348         case 0: /* 10-byte protocol */
 349                 if (elo_setup_10(elo))
 350                         goto fail3;
 351
 352                 break;
 353
 354         case 1: /* 6-byte protocol */
 355                 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
 356
 357         case 2: /* 4-byte protocol */
 358                 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
 359                 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
 360                 break;
 361
 362         case 3: /* 3-byte protocol */
 363                 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
 364                 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
 365                 break;
 366         }
 367
 368         err = input_register_device(elo->dev);
 369         if (err)
 370                 goto fail3;
 371
 372         return 0;
 373
 374  fail3: serio_close(serio);
 375  fail2: serio_set_drvdata(serio, NULL);
 376  fail1: input_free_device(input_dev);
 377         kfree(elo);
 378         return err;
 379 }
 380
 381 /*
 382  * The serio driver structure.
 383  */
 384
 385 static struct serio_device_id elo_serio_ids[] = {
 386         {
 387                 .type   = SERIO_RS232,
 388                 .proto  = SERIO_ELO,
 389                 .id     = SERIO_ANY,
 390                 .extra  = SERIO_ANY,
 391         },
 392         { 0 }
 393 };
 394
 395 MODULE_DEVICE_TABLE(serio, elo_serio_ids);
 396
 397 static struct serio_driver elo_drv = {
 398         .driver         = {
 399                 .name   = "elo",
 400         },
 401         .description    = DRIVER_DESC,
 402         .id_table       = elo_serio_ids,
 403         .interrupt      = elo_interrupt,
 404         .connect        = elo_connect,
 405         .disconnect     = elo_disconnect,
 406 };
 407
 408 /*
 409  * The functions for inserting/removing us as a module.
 410  */
 411
 412 static int __init elo_init(void)
 413 {
 414         return serio_register_driver(&elo_drv);
 415 }
 416
 417 static void __exit elo_exit(void)
 418 {
 419         serio_unregister_driver(&elo_drv);
 420 }
 421
 422 module_init(elo_init);
 423 module_exit(elo_exit);