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         switch (elo->idx++) {
  76                 case 0:
  77                         elo->csum = 0xaa;
  78                         if (data != ELO10_LEAD_BYTE) {
  79                                 pr_debug("elo: unsynchronized data: 0x%02x\n", data);
  80                                 elo->idx = 0;
  81                         }
  82                         break;
  83
  84                 case 9:
  85                         elo->idx = 0;
  86                         if (data != elo->csum) {
  87                                 pr_debug("elo: bad checksum: 0x%02x, expected 0x%02x\n",
  88                                          data, elo->csum);
  89                                 break;
  90                         }
  91                         if (elo->data[1] != elo->expected_packet) {
  92                                 if (elo->data[1] != ELO10_TOUCH_PACKET)
  93                                         pr_debug("elo: unexpected packet: 0x%02x\n",
  94                                                  elo->data[1]);
  95                                 break;
  96                         }
  97                         if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
  98                                 input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
  99                                 input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
 100                                 if (elo->data[2] & ELO10_PRESSURE)
 101                                         input_report_abs(dev, ABS_PRESSURE,
 102                                                         (elo->data[8] << 8) | elo->data[7]);
 103                                 input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
 104                                 input_sync(dev);
 105                         } else if (elo->data[1] == ELO10_ACK_PACKET) {
 106                                 if (elo->data[2] == '0')
 107                                         elo->expected_packet = ELO10_TOUCH_PACKET;
 108                                 complete(&elo->cmd_done);
 109                         } else {
 110                                 memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
 111                                 elo->expected_packet = ELO10_ACK_PACKET;
 112                         }
 113                         break;
 114         }
 115         elo->csum += data;
 116 }
 117
 118 static void elo_process_data_6(struct elo *elo, unsigned char data)
 119 {
 120         struct input_dev *dev = elo->dev;
 121
 122         elo->data[elo->idx] = data;
 123
 124         switch (elo->idx++) {
 125
 126                 case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break;
 127                 case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break;
 128                 case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break;
 129
 130                 case 3:
 131                         if (data & 0xc0) {
 132                                 elo->idx = 0;
 133                                 break;
 134                         }
 135
 136                         input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
 137                         input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
 138
 139                         if (elo->id == 2) {
 140                                 input_report_key(dev, BTN_TOUCH, 1);
 141                                 input_sync(dev);
 142                                 elo->idx = 0;
 143                         }
 144
 145                         break;
 146
 147                 case 4:
 148                         if (data) {
 149                                 input_sync(dev);
 150                                 elo->idx = 0;
 151                         }
 152                         break;
 153
 154                 case 5:
 155                         if ((data & 0xf0) == 0) {
 156                                 input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
 157                                 input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
 158                         }
 159                         input_sync(dev);
 160                         elo->idx = 0;
 161                         break;
 162         }
 163 }
 164
 165 static void elo_process_data_3(struct elo *elo, unsigned char data)
 166 {
 167         struct input_dev *dev = elo->dev;
 168
 169         elo->data[elo->idx] = data;
 170
 171         switch (elo->idx++) {
 172
 173                 case 0:
 174                         if ((data & 0x7f) != 0x01)
 175                                 elo->idx = 0;
 176                         break;
 177                 case 2:
 178                         input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
 179                         input_report_abs(dev, ABS_X, elo->data[1]);
 180                         input_report_abs(dev, ABS_Y, elo->data[2]);
 181                         input_sync(dev);
 182                         elo->idx = 0;
 183                         break;
 184         }
 185 }
 186
 187 static irqreturn_t elo_interrupt(struct serio *serio,
 188                 unsigned char data, unsigned int flags)
 189 {
 190         struct elo *elo = serio_get_drvdata(serio);
 191
 192         switch(elo->id) {
 193                 case 0:
 194                         elo_process_data_10(elo, data);
 195                         break;
 196
 197                 case 1:
 198                 case 2:
 199                         elo_process_data_6(elo, data);
 200                         break;
 201
 202                 case 3:
 203                         elo_process_data_3(elo, data);
 204                         break;
 205         }
 206
 207         return IRQ_HANDLED;
 208 }
 209
 210 static int elo_command_10(struct elo *elo, unsigned char *packet)
 211 {
 212         int rc = -1;
 213         int i;
 214         unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
 215
 216         mutex_lock(&elo->cmd_mutex);
 217
 218         serio_pause_rx(elo->serio);
 219         elo->expected_packet = toupper(packet[0]);
 220         init_completion(&elo->cmd_done);
 221         serio_continue_rx(elo->serio);
 222
 223         if (serio_write(elo->serio, ELO10_LEAD_BYTE))
 224                 goto out;
 225
 226         for (i = 0; i < ELO10_PACKET_LEN; i++) {
 227                 csum += packet[i];
 228                 if (serio_write(elo->serio, packet[i]))
 229                         goto out;
 230         }
 231
 232         if (serio_write(elo->serio, csum))
 233                 goto out;
 234
 235         wait_for_completion_timeout(&elo->cmd_done, HZ);
 236
 237         if (elo->expected_packet == ELO10_TOUCH_PACKET) {
 238                 /* We are back in reporting mode, the command was ACKed */
 239                 memcpy(packet, elo->response, ELO10_PACKET_LEN);
 240                 rc = 0;
 241         }
 242
 243  out:
 244         mutex_unlock(&elo->cmd_mutex);
 245         return rc;
 246 }
 247
 248 static int elo_setup_10(struct elo *elo)
 249 {
 250         static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
 251         struct input_dev *dev = elo->dev;
 252         unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
 253
 254         if (elo_command_10(elo, packet))
 255                 return -1;
 256
 257         dev->id.version = (packet[5] << 8) | packet[4];
 258
 259         input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
 260         input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
 261         if (packet[3] & ELO10_PRESSURE)
 262                 input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
 263
 264         printk(KERN_INFO "elo: %sTouch touchscreen, fw: %02x.%02x, "
 265                 "features: %x02x, controller: 0x%02x\n",
 266                 elo_types[(packet[1] -'0') & 0x03],
 267                 packet[5], packet[4], packet[3], packet[7]);
 268
 269         return 0;
 270 }
 271
 272 /*
 273  * elo_disconnect() is the opposite of elo_connect()
 274  */
 275
 276 static void elo_disconnect(struct serio *serio)
 277 {
 278         struct elo *elo = serio_get_drvdata(serio);
 279
 280         input_get_device(elo->dev);
 281         input_unregister_device(elo->dev);
 282         serio_close(serio);
 283         serio_set_drvdata(serio, NULL);
 284         input_put_device(elo->dev);
 285         kfree(elo);
 286 }
 287
 288 /*
 289  * elo_connect() is the routine that is called when someone adds a
 290  * new serio device that supports Gunze protocol and registers it as
 291  * an input device.
 292  */
 293
 294 static int elo_connect(struct serio *serio, struct serio_driver *drv)
 295 {
 296         struct elo *elo;
 297         struct input_dev *input_dev;
 298         int err;
 299
 300         elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
 301         input_dev = input_allocate_device();
 302         if (!elo || !input_dev) {
 303                 err = -ENOMEM;
 304                 goto fail1;
 305         }
 306
 307         elo->serio = serio;
 308         elo->id = serio->id.id;
 309         elo->dev = input_dev;
 310         elo->expected_packet = ELO10_TOUCH_PACKET;
 311         mutex_init(&elo->cmd_mutex);
 312         init_completion(&elo->cmd_done);
 313         snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
 314
 315         input_dev->private = elo;
 316         input_dev->name = "Elo Serial TouchScreen";
 317         input_dev->phys = elo->phys;
 318         input_dev->id.bustype = BUS_RS232;
 319         input_dev->id.vendor = SERIO_ELO;
 320         input_dev->id.product = elo->id;
 321         input_dev->id.version = 0x0100;
 322         input_dev->cdev.dev = &serio->dev;
 323
 324         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 325         input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
 326
 327         serio_set_drvdata(serio, elo);
 328         err = serio_open(serio, drv);
 329         if (err)
 330                 goto fail2;
 331
 332         switch (elo->id) {
 333
 334                 case 0: /* 10-byte protocol */
 335                         if (elo_setup_10(elo))
 336                                 goto fail3;
 337
 338                         break;
 339
 340                 case 1: /* 6-byte protocol */
 341                         input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
 342
 343                 case 2: /* 4-byte protocol */
 344                         input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
 345                         input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
 346                         break;
 347
 348                 case 3: /* 3-byte protocol */
 349                         input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
 350                         input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
 351                         break;
 352         }
 353
 354         err = input_register_device(elo->dev);
 355         if (err)
 356                 goto fail3;
 357
 358         return 0;
 359
 360  fail3: serio_close(serio);
 361  fail2: serio_set_drvdata(serio, NULL);
 362  fail1: input_free_device(input_dev);
 363         kfree(elo);
 364         return err;
 365 }
 366
 367 /*
 368  * The serio driver structure.
 369  */
 370
 371 static struct serio_device_id elo_serio_ids[] = {
 372         {
 373                 .type   = SERIO_RS232,
 374                 .proto  = SERIO_ELO,
 375                 .id     = SERIO_ANY,
 376                 .extra  = SERIO_ANY,
 377         },
 378         { 0 }
 379 };
 380
 381 MODULE_DEVICE_TABLE(serio, elo_serio_ids);
 382
 383 static struct serio_driver elo_drv = {
 384         .driver         = {
 385                 .name   = "elo",
 386         },
 387         .description    = DRIVER_DESC,
 388         .id_table       = elo_serio_ids,
 389         .interrupt      = elo_interrupt,
 390         .connect        = elo_connect,
 391         .disconnect     = elo_disconnect,
 392 };
 393
 394 /*
 395  * The functions for inserting/removing us as a module.
 396  */
 397
 398 static int __init elo_init(void)
 399 {
 400         return serio_register_driver(&elo_drv);
 401 }
 402
 403 static void __exit elo_exit(void)
 404 {
 405         serio_unregister_driver(&elo_drv);
 406 }
 407
 408 module_init(elo_init);
 409 module_exit(elo_exit);