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