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 module_serio_driver(elo_drv); 409