drivers/input/touchscreen/touchright.c

   1 /*
   2  * Touchright serial touchscreen driver
   3  *
   4  * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
   5  *
   6  * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c)
   7  * Copyright (c) 2004 Vojtech Pavlik
   8  * and Dan Streetman <ddstreet@ieee.org>
   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/serio.h>
  23 #include <linux/init.h>
  24
  25 #define DRIVER_DESC     "Touchright serial touchscreen driver"
  26
  27 MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
  28 MODULE_DESCRIPTION(DRIVER_DESC);
  29 MODULE_LICENSE("GPL");
  30
  31 /*
  32  * Definitions & global arrays.
  33  */
  34
  35 #define TR_FORMAT_TOUCH_BIT     0x01
  36 #define TR_FORMAT_STATUS_BYTE   0x40
  37 #define TR_FORMAT_STATUS_MASK   ~TR_FORMAT_TOUCH_BIT
  38
  39 #define TR_LENGTH 5
  40
  41 #define TR_MIN_XC 0
  42 #define TR_MAX_XC 0x1ff
  43 #define TR_MIN_YC 0
  44 #define TR_MAX_YC 0x1ff
  45
  46 /*
  47  * Per-touchscreen data.
  48  */
  49
  50 struct tr {
  51         struct input_dev *dev;
  52         struct serio *serio;
  53         int idx;
  54         unsigned char data[TR_LENGTH];
  55         char phys[32];
  56 };
  57
  58 static irqreturn_t tr_interrupt(struct serio *serio,
  59                 unsigned char data, unsigned int flags)
  60 {
  61         struct tr *tr = serio_get_drvdata(serio);
  62         struct input_dev *dev = tr->dev;
  63
  64         tr->data[tr->idx] = data;
  65
  66         if ((tr->data[0] & TR_FORMAT_STATUS_MASK) == TR_FORMAT_STATUS_BYTE) {
  67                 if (++tr->idx == TR_LENGTH) {
  68                         input_report_abs(dev, ABS_X,
  69                                 (tr->data[1] << 5) | (tr->data[2] >> 1));
  70                         input_report_abs(dev, ABS_Y,
  71                                 (tr->data[3] << 5) | (tr->data[4] >> 1));
  72                         input_report_key(dev, BTN_TOUCH,
  73                                 tr->data[0] & TR_FORMAT_TOUCH_BIT);
  74                         input_sync(dev);
  75                         tr->idx = 0;
  76                 }
  77         }
  78
  79         return IRQ_HANDLED;
  80 }
  81
  82 /*
  83  * tr_disconnect() is the opposite of tr_connect()
  84  */
  85
  86 static void tr_disconnect(struct serio *serio)
  87 {
  88         struct tr *tr = serio_get_drvdata(serio);
  89
  90         input_get_device(tr->dev);
  91         input_unregister_device(tr->dev);
  92         serio_close(serio);
  93         serio_set_drvdata(serio, NULL);
  94         input_put_device(tr->dev);
  95         kfree(tr);
  96 }
  97
  98 /*
  99  * tr_connect() is the routine that is called when someone adds a
 100  * new serio device that supports the Touchright protocol and registers it as
 101  * an input device.
 102  */
 103
 104 static int tr_connect(struct serio *serio, struct serio_driver *drv)
 105 {
 106         struct tr *tr;
 107         struct input_dev *input_dev;
 108         int err;
 109
 110         tr = kzalloc(sizeof(struct tr), GFP_KERNEL);
 111         input_dev = input_allocate_device();
 112         if (!tr || !input_dev) {
 113                 err = -ENOMEM;
 114                 goto fail1;
 115         }
 116
 117         tr->serio = serio;
 118         tr->dev = input_dev;
 119         snprintf(tr->phys, sizeof(tr->phys), "%s/input0", serio->phys);
 120
 121         input_dev->private = tr;
 122         input_dev->name = "Touchright Serial TouchScreen";
 123         input_dev->phys = tr->phys;
 124         input_dev->id.bustype = BUS_RS232;
 125         input_dev->id.vendor = SERIO_TOUCHRIGHT;
 126         input_dev->id.product = 0;
 127         input_dev->id.version = 0x0100;
 128         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 129         input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
 130         input_set_abs_params(tr->dev, ABS_X, TR_MIN_XC, TR_MAX_XC, 0, 0);
 131         input_set_abs_params(tr->dev, ABS_Y, TR_MIN_YC, TR_MAX_YC, 0, 0);
 132
 133         serio_set_drvdata(serio, tr);
 134
 135         err = serio_open(serio, drv);
 136         if (err)
 137                 goto fail2;
 138
 139         err = input_register_device(tr->dev);
 140         if (err)
 141                 goto fail3;
 142
 143         return 0;
 144
 145  fail3: serio_close(serio);
 146  fail2: serio_set_drvdata(serio, NULL);
 147  fail1: input_free_device(input_dev);
 148         kfree(tr);
 149         return err;
 150 }
 151
 152 /*
 153  * The serio driver structure.
 154  */
 155
 156 static struct serio_device_id tr_serio_ids[] = {
 157         {
 158                 .type   = SERIO_RS232,
 159                 .proto  = SERIO_TOUCHRIGHT,
 160                 .id     = SERIO_ANY,
 161                 .extra  = SERIO_ANY,
 162         },
 163         { 0 }
 164 };
 165
 166 MODULE_DEVICE_TABLE(serio, tr_serio_ids);
 167
 168 static struct serio_driver tr_drv = {
 169         .driver         = {
 170                 .name   = "touchright",
 171         },
 172         .description    = DRIVER_DESC,
 173         .id_table       = tr_serio_ids,
 174         .interrupt      = tr_interrupt,
 175         .connect        = tr_connect,
 176         .disconnect     = tr_disconnect,
 177 };
 178
 179 /*
 180  * The functions for inserting/removing us as a module.
 181  */
 182
 183 static int __init tr_init(void)
 184 {
 185         return serio_register_driver(&tr_drv);
 186 }
 187
 188 static void __exit tr_exit(void)
 189 {
 190         serio_unregister_driver(&tr_drv);
 191 }
 192
 193 module_init(tr_init);
 194 module_exit(tr_exit);