1 /* 2 * Penmount serial touchscreen driver 3 * 4 * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com> 5 * Copyright (c) 2011 John Sung <penmount.touch@gmail.com> 6 * 7 * Based on ELO driver (drivers/input/touchscreen/elo.c) 8 * Copyright (c) 2004 Vojtech Pavlik 9 */ 10 11 /* 12 * This program is free software; you can redistribute it and/or modify it 13 * under the terms of the GNU General Public License version 2 as published 14 * by the Free Software Foundation. 15 */ 16 17 #include <linux/errno.h> 18 #include <linux/kernel.h> 19 #include <linux/module.h> 20 #include <linux/slab.h> 21 #include <linux/input.h> 22 #include <linux/input/mt.h> 23 #include <linux/serio.h> 24 25 #define DRIVER_DESC "PenMount serial touchscreen driver" 26 27 MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>"); 28 MODULE_AUTHOR("John Sung <penmount.touch@gmail.com>"); 29 MODULE_DESCRIPTION(DRIVER_DESC); 30 MODULE_LICENSE("GPL"); 31 32 /* 33 * Definitions & global arrays. 34 */ 35 36 #define PM_MAX_LENGTH 6 37 #define PM_MAX_MTSLOT 16 38 #define PM_3000_MTSLOT 2 39 #define PM_6250_MTSLOT 12 40 41 /* 42 * Multi-touch slot 43 */ 44 45 struct mt_slot { 46 unsigned short x, y; 47 bool active; /* is the touch valid? */ 48 }; 49 50 /* 51 * Per-touchscreen data. 52 */ 53 54 struct pm { 55 struct input_dev *dev; 56 struct serio *serio; 57 int idx; 58 unsigned char data[PM_MAX_LENGTH]; 59 char phys[32]; 60 unsigned char packetsize; 61 unsigned char maxcontacts; 62 struct mt_slot slots[PM_MAX_MTSLOT]; 63 void (*parse_packet)(struct pm *); 64 }; 65 66 /* 67 * pm_mtevent() sends mt events and also emulates pointer movement 68 */ 69 70 static void pm_mtevent(struct pm *pm, struct input_dev *input) 71 { 72 int i; 73 74 for (i = 0; i < pm->maxcontacts; ++i) { 75 input_mt_slot(input, i); 76 input_mt_report_slot_state(input, MT_TOOL_FINGER, 77 pm->slots[i].active); 78 if (pm->slots[i].active) { 79 input_event(input, EV_ABS, ABS_MT_POSITION_X, pm->slots[i].x); 80 input_event(input, EV_ABS, ABS_MT_POSITION_Y, pm->slots[i].y); 81 } 82 } 83 84 input_mt_report_pointer_emulation(input, true); 85 input_sync(input); 86 } 87 88 /* 89 * pm_checkpacket() checks if data packet is valid 90 */ 91 92 static bool pm_checkpacket(unsigned char *packet) 93 { 94 int total = 0; 95 int i; 96 97 for (i = 0; i < 5; i++) 98 total += packet[i]; 99 100 return packet[5] == (unsigned char)~(total & 0xff); 101 } 102 103 static void pm_parse_9000(struct pm *pm) 104 { 105 struct input_dev *dev = pm->dev; 106 107 if ((pm->data[0] & 0x80) && pm->packetsize == ++pm->idx) { 108 input_report_abs(dev, ABS_X, pm->data[1] * 128 + pm->data[2]); 109 input_report_abs(dev, ABS_Y, pm->data[3] * 128 + pm->data[4]); 110 input_report_key(dev, BTN_TOUCH, !!(pm->data[0] & 0x40)); 111 input_sync(dev); 112 pm->idx = 0; 113 } 114 } 115 116 static void pm_parse_6000(struct pm *pm) 117 { 118 struct input_dev *dev = pm->dev; 119 120 if ((pm->data[0] & 0xbf) == 0x30 && pm->packetsize == ++pm->idx) { 121 if (pm_checkpacket(pm->data)) { 122 input_report_abs(dev, ABS_X, 123 pm->data[2] * 256 + pm->data[1]); 124 input_report_abs(dev, ABS_Y, 125 pm->data[4] * 256 + pm->data[3]); 126 input_report_key(dev, BTN_TOUCH, pm->data[0] & 0x40); 127 input_sync(dev); 128 } 129 pm->idx = 0; 130 } 131 } 132 133 static void pm_parse_3000(struct pm *pm) 134 { 135 struct input_dev *dev = pm->dev; 136 137 if ((pm->data[0] & 0xce) == 0x40 && pm->packetsize == ++pm->idx) { 138 if (pm_checkpacket(pm->data)) { 139 int slotnum = pm->data[0] & 0x0f; 140 pm->slots[slotnum].active = pm->data[0] & 0x30; 141 pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1]; 142 pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3]; 143 pm_mtevent(pm, dev); 144 } 145 pm->idx = 0; 146 } 147 } 148 149 static void pm_parse_6250(struct pm *pm) 150 { 151 struct input_dev *dev = pm->dev; 152 153 if ((pm->data[0] & 0xb0) == 0x30 && pm->packetsize == ++pm->idx) { 154 if (pm_checkpacket(pm->data)) { 155 int slotnum = pm->data[0] & 0x0f; 156 pm->slots[slotnum].active = pm->data[0] & 0x40; 157 pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1]; 158 pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3]; 159 pm_mtevent(pm, dev); 160 } 161 pm->idx = 0; 162 } 163 } 164 165 static irqreturn_t pm_interrupt(struct serio *serio, 166 unsigned char data, unsigned int flags) 167 { 168 struct pm *pm = serio_get_drvdata(serio); 169 170 pm->data[pm->idx] = data; 171 172 pm->parse_packet(pm); 173 174 return IRQ_HANDLED; 175 } 176 177 /* 178 * pm_disconnect() is the opposite of pm_connect() 179 */ 180 181 static void pm_disconnect(struct serio *serio) 182 { 183 struct pm *pm = serio_get_drvdata(serio); 184 185 serio_close(serio); 186 187 input_unregister_device(pm->dev); 188 kfree(pm); 189 190 serio_set_drvdata(serio, NULL); 191 } 192 193 /* 194 * pm_connect() is the routine that is called when someone adds a 195 * new serio device that supports PenMount protocol and registers it as 196 * an input device. 197 */ 198 199 static int pm_connect(struct serio *serio, struct serio_driver *drv) 200 { 201 struct pm *pm; 202 struct input_dev *input_dev; 203 int max_x, max_y; 204 int err; 205 206 pm = kzalloc(sizeof(struct pm), GFP_KERNEL); 207 input_dev = input_allocate_device(); 208 if (!pm || !input_dev) { 209 err = -ENOMEM; 210 goto fail1; 211 } 212 213 pm->serio = serio; 214 pm->dev = input_dev; 215 snprintf(pm->phys, sizeof(pm->phys), "%s/input0", serio->phys); 216 pm->maxcontacts = 1; 217 218 input_dev->name = "PenMount Serial TouchScreen"; 219 input_dev->phys = pm->phys; 220 input_dev->id.bustype = BUS_RS232; 221 input_dev->id.vendor = SERIO_PENMOUNT; 222 input_dev->id.product = 0; 223 input_dev->id.version = 0x0100; 224 input_dev->dev.parent = &serio->dev; 225 226 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 227 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 228 229 switch (serio->id.id) { 230 default: 231 case 0: 232 pm->packetsize = 5; 233 pm->parse_packet = pm_parse_9000; 234 input_dev->id.product = 0x9000; 235 max_x = max_y = 0x3ff; 236 break; 237 238 case 1: 239 pm->packetsize = 6; 240 pm->parse_packet = pm_parse_6000; 241 input_dev->id.product = 0x6000; 242 max_x = max_y = 0x3ff; 243 break; 244 245 case 2: 246 pm->packetsize = 6; 247 pm->parse_packet = pm_parse_3000; 248 input_dev->id.product = 0x3000; 249 max_x = max_y = 0x7ff; 250 pm->maxcontacts = PM_3000_MTSLOT; 251 break; 252 253 case 3: 254 pm->packetsize = 6; 255 pm->parse_packet = pm_parse_6250; 256 input_dev->id.product = 0x6250; 257 max_x = max_y = 0x3ff; 258 pm->maxcontacts = PM_6250_MTSLOT; 259 break; 260 } 261 262 input_set_abs_params(pm->dev, ABS_X, 0, max_x, 0, 0); 263 input_set_abs_params(pm->dev, ABS_Y, 0, max_y, 0, 0); 264 265 if (pm->maxcontacts > 1) { 266 input_mt_init_slots(pm->dev, pm->maxcontacts, 0); 267 input_set_abs_params(pm->dev, 268 ABS_MT_POSITION_X, 0, max_x, 0, 0); 269 input_set_abs_params(pm->dev, 270 ABS_MT_POSITION_Y, 0, max_y, 0, 0); 271 } 272 273 serio_set_drvdata(serio, pm); 274 275 err = serio_open(serio, drv); 276 if (err) 277 goto fail2; 278 279 err = input_register_device(pm->dev); 280 if (err) 281 goto fail3; 282 283 return 0; 284 285 fail3: serio_close(serio); 286 fail2: serio_set_drvdata(serio, NULL); 287 fail1: input_free_device(input_dev); 288 kfree(pm); 289 return err; 290 } 291 292 /* 293 * The serio driver structure. 294 */ 295 296 static const struct serio_device_id pm_serio_ids[] = { 297 { 298 .type = SERIO_RS232, 299 .proto = SERIO_PENMOUNT, 300 .id = SERIO_ANY, 301 .extra = SERIO_ANY, 302 }, 303 { 0 } 304 }; 305 306 MODULE_DEVICE_TABLE(serio, pm_serio_ids); 307 308 static struct serio_driver pm_drv = { 309 .driver = { 310 .name = "serio-penmount", 311 }, 312 .description = DRIVER_DESC, 313 .id_table = pm_serio_ids, 314 .interrupt = pm_interrupt, 315 .connect = pm_connect, 316 .disconnect = pm_disconnect, 317 }; 318 319 module_serio_driver(pm_drv); 320