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: 0x%02x, 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->name = "Elo Serial TouchScreen"; 316 input_dev->phys = elo->phys; 317 input_dev->id.bustype = BUS_RS232; 318 input_dev->id.vendor = SERIO_ELO; 319 input_dev->id.product = elo->id; 320 input_dev->id.version = 0x0100; 321 input_dev->dev.parent = &serio->dev; 322 323 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 324 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 325 326 serio_set_drvdata(serio, elo); 327 err = serio_open(serio, drv); 328 if (err) 329 goto fail2; 330 331 switch (elo->id) { 332 333 case 0: /* 10-byte protocol */ 334 if (elo_setup_10(elo)) 335 goto fail3; 336 337 break; 338 339 case 1: /* 6-byte protocol */ 340 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0); 341 342 case 2: /* 4-byte protocol */ 343 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0); 344 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0); 345 break; 346 347 case 3: /* 3-byte protocol */ 348 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0); 349 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0); 350 break; 351 } 352 353 err = input_register_device(elo->dev); 354 if (err) 355 goto fail3; 356 357 return 0; 358 359 fail3: serio_close(serio); 360 fail2: serio_set_drvdata(serio, NULL); 361 fail1: input_free_device(input_dev); 362 kfree(elo); 363 return err; 364 } 365 366 /* 367 * The serio driver structure. 368 */ 369 370 static struct serio_device_id elo_serio_ids[] = { 371 { 372 .type = SERIO_RS232, 373 .proto = SERIO_ELO, 374 .id = SERIO_ANY, 375 .extra = SERIO_ANY, 376 }, 377 { 0 } 378 }; 379 380 MODULE_DEVICE_TABLE(serio, elo_serio_ids); 381 382 static struct serio_driver elo_drv = { 383 .driver = { 384 .name = "elo", 385 }, 386 .description = DRIVER_DESC, 387 .id_table = elo_serio_ids, 388 .interrupt = elo_interrupt, 389 .connect = elo_connect, 390 .disconnect = elo_disconnect, 391 }; 392 393 /* 394 * The functions for inserting/removing us as a module. 395 */ 396 397 static int __init elo_init(void) 398 { 399 return serio_register_driver(&elo_drv); 400 } 401 402 static void __exit elo_exit(void) 403 { 404 serio_unregister_driver(&elo_drv); 405 } 406 407 module_init(elo_init); 408 module_exit(elo_exit); 409