drivers/input/touchscreen/penmount.c

   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 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);