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 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 /* 40 * Per-touchscreen data. 41 */ 42 43 struct elo { 44 struct input_dev *dev; 45 struct serio *serio; 46 int id; 47 int idx; 48 unsigned char csum; 49 unsigned char data[ELO_MAX_LENGTH]; 50 char phys[32]; 51 }; 52 53 static void elo_process_data_10(struct elo* elo, unsigned char data, struct pt_regs *regs) 54 { 55 struct input_dev *dev = elo->dev; 56 57 elo->csum += elo->data[elo->idx] = data; 58 59 switch (elo->idx++) { 60 61 case 0: 62 if (data != 'U') { 63 elo->idx = 0; 64 elo->csum = 0; 65 } 66 break; 67 68 case 1: 69 if (data != 'T') { 70 elo->idx = 0; 71 elo->csum = 0; 72 } 73 break; 74 75 case 9: 76 if (elo->csum) { 77 input_regs(dev, regs); 78 input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]); 79 input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]); 80 input_report_abs(dev, ABS_PRESSURE, (elo->data[8] << 8) | elo->data[7]); 81 input_report_key(dev, BTN_TOUCH, elo->data[8] || elo->data[7]); 82 input_sync(dev); 83 } 84 elo->idx = 0; 85 elo->csum = 0; 86 break; 87 } 88 } 89 90 static void elo_process_data_6(struct elo* elo, unsigned char data, struct pt_regs *regs) 91 { 92 struct input_dev *dev = elo->dev; 93 94 elo->data[elo->idx] = data; 95 96 switch (elo->idx++) { 97 98 case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break; 99 case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break; 100 case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break; 101 102 case 3: 103 if (data & 0xc0) { 104 elo->idx = 0; 105 break; 106 } 107 108 input_regs(dev, regs); 109 input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f)); 110 input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f)); 111 112 if (elo->id == 2) { 113 input_report_key(dev, BTN_TOUCH, 1); 114 input_sync(dev); 115 elo->idx = 0; 116 } 117 118 break; 119 120 case 4: 121 if (data) { 122 input_sync(dev); 123 elo->idx = 0; 124 } 125 break; 126 127 case 5: 128 if ((data & 0xf0) == 0) { 129 input_report_abs(dev, ABS_PRESSURE, elo->data[5]); 130 input_report_key(dev, BTN_TOUCH, !!elo->data[5]); 131 } 132 input_sync(dev); 133 elo->idx = 0; 134 break; 135 } 136 } 137 138 static void elo_process_data_3(struct elo* elo, unsigned char data, struct pt_regs *regs) 139 { 140 struct input_dev *dev = elo->dev; 141 142 elo->data[elo->idx] = data; 143 144 switch (elo->idx++) { 145 146 case 0: 147 if ((data & 0x7f) != 0x01) 148 elo->idx = 0; 149 break; 150 case 2: 151 input_regs(dev, regs); 152 input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80)); 153 input_report_abs(dev, ABS_X, elo->data[1]); 154 input_report_abs(dev, ABS_Y, elo->data[2]); 155 input_sync(dev); 156 elo->idx = 0; 157 break; 158 } 159 } 160 161 static irqreturn_t elo_interrupt(struct serio *serio, 162 unsigned char data, unsigned int flags, struct pt_regs *regs) 163 { 164 struct elo* elo = serio_get_drvdata(serio); 165 166 switch(elo->id) { 167 case 0: 168 elo_process_data_10(elo, data, regs); 169 break; 170 171 case 1: 172 case 2: 173 elo_process_data_6(elo, data, regs); 174 break; 175 176 case 3: 177 elo_process_data_3(elo, data, regs); 178 break; 179 } 180 181 return IRQ_HANDLED; 182 } 183 184 /* 185 * elo_disconnect() is the opposite of elo_connect() 186 */ 187 188 static void elo_disconnect(struct serio *serio) 189 { 190 struct elo* elo = serio_get_drvdata(serio); 191 192 input_unregister_device(elo->dev); 193 serio_close(serio); 194 serio_set_drvdata(serio, NULL); 195 kfree(elo); 196 } 197 198 /* 199 * elo_connect() is the routine that is called when someone adds a 200 * new serio device that supports Gunze protocol and registers it as 201 * an input device. 202 */ 203 204 static int elo_connect(struct serio *serio, struct serio_driver *drv) 205 { 206 struct elo *elo; 207 struct input_dev *input_dev; 208 int err; 209 210 elo = kzalloc(sizeof(struct elo), GFP_KERNEL); 211 input_dev = input_allocate_device(); 212 if (!elo || !input_dev) { 213 err = -ENOMEM; 214 goto fail; 215 } 216 217 elo->serio = serio; 218 elo->id = serio->id.id; 219 elo->dev = input_dev; 220 snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys); 221 222 input_dev->private = elo; 223 input_dev->name = "Elo Serial TouchScreen"; 224 input_dev->phys = elo->phys; 225 input_dev->id.bustype = BUS_RS232; 226 input_dev->id.vendor = SERIO_ELO; 227 input_dev->id.product = elo->id; 228 input_dev->id.version = 0x0100; 229 input_dev->cdev.dev = &serio->dev; 230 231 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS); 232 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH); 233 234 switch (elo->id) { 235 236 case 0: /* 10-byte protocol */ 237 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0); 238 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0); 239 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 255, 0, 0); 240 break; 241 242 case 1: /* 6-byte protocol */ 243 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0); 244 245 case 2: /* 4-byte protocol */ 246 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0); 247 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0); 248 break; 249 250 case 3: /* 3-byte protocol */ 251 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0); 252 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0); 253 break; 254 } 255 256 serio_set_drvdata(serio, elo); 257 258 err = serio_open(serio, drv); 259 if (err) 260 goto fail; 261 262 input_register_device(elo->dev); 263 return 0; 264 265 fail: serio_set_drvdata(serio, NULL); 266 input_free_device(input_dev); 267 kfree(elo); 268 return err; 269 } 270 271 /* 272 * The serio driver structure. 273 */ 274 275 static struct serio_device_id elo_serio_ids[] = { 276 { 277 .type = SERIO_RS232, 278 .proto = SERIO_ELO, 279 .id = SERIO_ANY, 280 .extra = SERIO_ANY, 281 }, 282 { 0 } 283 }; 284 285 MODULE_DEVICE_TABLE(serio, elo_serio_ids); 286 287 static struct serio_driver elo_drv = { 288 .driver = { 289 .name = "elo", 290 }, 291 .description = DRIVER_DESC, 292 .id_table = elo_serio_ids, 293 .interrupt = elo_interrupt, 294 .connect = elo_connect, 295 .disconnect = elo_disconnect, 296 }; 297 298 /* 299 * The functions for inserting/removing us as a module. 300 */ 301 302 static int __init elo_init(void) 303 { 304 serio_register_driver(&elo_drv); 305 return 0; 306 } 307 308 static void __exit elo_exit(void) 309 { 310 serio_unregister_driver(&elo_drv); 311 } 312 313 module_init(elo_init); 314 module_exit(elo_exit); 315