LXR linux/drivers/input/touchscreen/inexio.c

   1/*
   2 * iNexio serial touchscreen driver
   3 *
   4 * Copyright (c) 2008 Richard Lemon
   5 * Based on the mtouch driver (c) Vojtech Pavlik and Dan Streetman
   6 *
   7 */
   8
   9/*
  10 * This program is free software; you can redistribute it and/or modify it
  11 * under the terms of the GNU General Public License version 2 as published by
  12 * the Free Software Foundation.
  13 */
  14
  15/*
  16 * 2008/06/19 Richard Lemon <richard@codelemon.com>
  17 *   Copied mtouch.c and edited for iNexio protocol
  18 */
  19
  20#include <linux/errno.h>
  21#include <linux/kernel.h>
  22#include <linux/module.h>
  23#include <linux/slab.h>
  24#include <linux/input.h>
  25#include <linux/serio.h>
  26
  27#define DRIVER_DESC     "iNexio serial touchscreen driver"
  28
  29MODULE_AUTHOR("Richard Lemon <richard@codelemon.com>");
  30MODULE_DESCRIPTION(DRIVER_DESC);
  31MODULE_LICENSE("GPL");
  32
  33/*
  34 * Definitions & global arrays.
  35 */
  36
  37#define INEXIO_FORMAT_TOUCH_BIT 0x01
  38#define INEXIO_FORMAT_LENGTH 5
  39#define INEXIO_RESPONSE_BEGIN_BYTE 0x80
  40
  41/* todo: check specs for max length of all responses */
  42#define INEXIO_MAX_LENGTH 16
  43
  44#define INEXIO_MIN_XC 0
  45#define INEXIO_MAX_XC 0x3fff
  46#define INEXIO_MIN_YC 0
  47#define INEXIO_MAX_YC 0x3fff
  48
  49#define INEXIO_GET_XC(data) (((data[1])<<7) | data[2])
  50#define INEXIO_GET_YC(data) (((data[3])<<7) | data[4])
  51#define INEXIO_GET_TOUCHED(data) (INEXIO_FORMAT_TOUCH_BIT & data[0])
  52
  53/*
  54 * Per-touchscreen data.
  55 */
  56
  57struct inexio {
  58        struct input_dev *dev;
  59        struct serio *serio;
  60        int idx;
  61        unsigned char data[INEXIO_MAX_LENGTH];
  62        char phys[32];
  63};
  64
  65static void inexio_process_data(struct inexio *pinexio)
  66{
  67        struct input_dev *dev = pinexio->dev;
  68
  69        if (INEXIO_FORMAT_LENGTH == ++pinexio->idx) {
  70                input_report_abs(dev, ABS_X, INEXIO_GET_XC(pinexio->data));
  71                input_report_abs(dev, ABS_Y, INEXIO_GET_YC(pinexio->data));
  72                input_report_key(dev, BTN_TOUCH, INEXIO_GET_TOUCHED(pinexio->data));
  73                input_sync(dev);
  74
  75                pinexio->idx = 0;
  76        }
  77}
  78
  79static irqreturn_t inexio_interrupt(struct serio *serio,
  80                unsigned char data, unsigned int flags)
  81{
  82        struct inexio* pinexio = serio_get_drvdata(serio);
  83
  84        pinexio->data[pinexio->idx] = data;
  85
  86        if (INEXIO_RESPONSE_BEGIN_BYTE&pinexio->data[0])
  87                inexio_process_data(pinexio);
  88        else
  89                printk(KERN_DEBUG "inexio.c: unknown/unsynchronized data from device, byte %x\n",pinexio->data[0]);
  90
  91        return IRQ_HANDLED;
  92}
  93
  94/*
  95 * inexio_disconnect() is the opposite of inexio_connect()
  96 */
  97
  98static void inexio_disconnect(struct serio *serio)
  99{
 100        struct inexio* pinexio = serio_get_drvdata(serio);
 101
 102        input_get_device(pinexio->dev);
 103        input_unregister_device(pinexio->dev);
 104        serio_close(serio);
 105        serio_set_drvdata(serio, NULL);
 106        input_put_device(pinexio->dev);
 107        kfree(pinexio);
 108}
 109
 110/*
 111 * inexio_connect() is the routine that is called when someone adds a
 112 * new serio device that supports iNexio protocol and registers it as
 113 * an input device. This is usually accomplished using inputattach.
 114 */
 115
 116static int inexio_connect(struct serio *serio, struct serio_driver *drv)
 117{
 118        struct inexio *pinexio;
 119        struct input_dev *input_dev;
 120        int err;
 121
 122        pinexio = kzalloc(sizeof(struct inexio), GFP_KERNEL);
 123        input_dev = input_allocate_device();
 124        if (!pinexio || !input_dev) {
 125                err = -ENOMEM;
 126                goto fail1;
 127        }
 128
 129        pinexio->serio = serio;
 130        pinexio->dev = input_dev;
 131        snprintf(pinexio->phys, sizeof(pinexio->phys), "%s/input0", serio->phys);
 132
 133        input_dev->name = "iNexio Serial TouchScreen";
 134        input_dev->phys = pinexio->phys;
 135        input_dev->id.bustype = BUS_RS232;
 136        input_dev->id.vendor = SERIO_INEXIO;
 137        input_dev->id.product = 0;
 138        input_dev->id.version = 0x0001;
 139        input_dev->dev.parent = &serio->dev;
 140        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 141        input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 142        input_set_abs_params(pinexio->dev, ABS_X, INEXIO_MIN_XC, INEXIO_MAX_XC, 0, 0);
 143        input_set_abs_params(pinexio->dev, ABS_Y, INEXIO_MIN_YC, INEXIO_MAX_YC, 0, 0);
 144
 145        serio_set_drvdata(serio, pinexio);
 146
 147        err = serio_open(serio, drv);
 148        if (err)
 149                goto fail2;
 150
 151        err = input_register_device(pinexio->dev);
 152        if (err)
 153                goto fail3;
 154
 155        return 0;
 156
 157 fail3: serio_close(serio);
 158 fail2: serio_set_drvdata(serio, NULL);
 159 fail1: input_free_device(input_dev);
 160        kfree(pinexio);
 161        return err;
 162}
 163
 164/*
 165 * The serio driver structure.
 166 */
 167
 168static struct serio_device_id inexio_serio_ids[] = {
 169        {
 170                .type   = SERIO_RS232,
 171                .proto  = SERIO_INEXIO,
 172                .id     = SERIO_ANY,
 173                .extra  = SERIO_ANY,
 174        },
 175        { 0 }
 176};
 177
 178MODULE_DEVICE_TABLE(serio, inexio_serio_ids);
 179
 180static struct serio_driver inexio_drv = {
 181        .driver         = {
 182                .name   = "inexio",
 183        },
 184        .description    = DRIVER_DESC,
 185        .id_table       = inexio_serio_ids,
 186        .interrupt      = inexio_interrupt,
 187        .connect        = inexio_connect,
 188        .disconnect     = inexio_disconnect,
 189};
 190
 191module_serio_driver(inexio_drv);
 192