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#include <linux/init.h>
  27
  28#define DRIVER_DESC     "iNexio serial touchscreen driver"
  29
  30MODULE_AUTHOR("Richard Lemon <richard@codelemon.com>");
  31MODULE_DESCRIPTION(DRIVER_DESC);
  32MODULE_LICENSE("GPL");
  33
  34/*
  35 * Definitions & global arrays.
  36 */
  37
  38#define INEXIO_FORMAT_TOUCH_BIT 0x01
  39#define INEXIO_FORMAT_LENGTH 5
  40#define INEXIO_RESPONSE_BEGIN_BYTE 0x80
  41
  42/* todo: check specs for max length of all responses */
  43#define INEXIO_MAX_LENGTH 16
  44
  45#define INEXIO_MIN_XC 0
  46#define INEXIO_MAX_XC 0x3fff
  47#define INEXIO_MIN_YC 0
  48#define INEXIO_MAX_YC 0x3fff
  49
  50#define INEXIO_GET_XC(data) (((data[1])<<7) | data[2])
  51#define INEXIO_GET_YC(data) (((data[3])<<7) | data[4])
  52#define INEXIO_GET_TOUCHED(data) (INEXIO_FORMAT_TOUCH_BIT & data[0])
  53
  54/*
  55 * Per-touchscreen data.
  56 */
  57
  58struct inexio {
  59        struct input_dev *dev;
  60        struct serio *serio;
  61        int idx;
  62        unsigned char data[INEXIO_MAX_LENGTH];
  63        char phys[32];
  64};
  65
  66static void inexio_process_data(struct inexio *pinexio)
  67{
  68        struct input_dev *dev = pinexio->dev;
  69
  70        if (INEXIO_FORMAT_LENGTH == ++pinexio->idx) {
  71                input_report_abs(dev, ABS_X, INEXIO_GET_XC(pinexio->data));
  72                input_report_abs(dev, ABS_Y, INEXIO_GET_YC(pinexio->data));
  73                input_report_key(dev, BTN_TOUCH, INEXIO_GET_TOUCHED(pinexio->data));
  74                input_sync(dev);
  75
  76                pinexio->idx = 0;
  77        }
  78}
  79
  80static irqreturn_t inexio_interrupt(struct serio *serio,
  81                unsigned char data, unsigned int flags)
  82{
  83        struct inexio* pinexio = serio_get_drvdata(serio);
  84
  85        pinexio->data[pinexio->idx] = data;
  86
  87        if (INEXIO_RESPONSE_BEGIN_BYTE&pinexio->data[0])
  88                inexio_process_data(pinexio);
  89        else
  90                printk(KERN_DEBUG "inexio.c: unknown/unsynchronized data from device, byte %x\n",pinexio->data[0]);
  91
  92        return IRQ_HANDLED;
  93}
  94
  95/*
  96 * inexio_disconnect() is the opposite of inexio_connect()
  97 */
  98
  99static void inexio_disconnect(struct serio *serio)
 100{
 101        struct inexio* pinexio = serio_get_drvdata(serio);
 102
 103        input_get_device(pinexio->dev);
 104        input_unregister_device(pinexio->dev);
 105        serio_close(serio);
 106        serio_set_drvdata(serio, NULL);
 107        input_put_device(pinexio->dev);
 108        kfree(pinexio);
 109}
 110
 111/*
 112 * inexio_connect() is the routine that is called when someone adds a
 113 * new serio device that supports iNexio protocol and registers it as
 114 * an input device. This is usually accomplished using inputattach.
 115 */
 116
 117static int inexio_connect(struct serio *serio, struct serio_driver *drv)
 118{
 119        struct inexio *pinexio;
 120        struct input_dev *input_dev;
 121        int err;
 122
 123        pinexio = kzalloc(sizeof(struct inexio), GFP_KERNEL);
 124        input_dev = input_allocate_device();
 125        if (!pinexio || !input_dev) {
 126                err = -ENOMEM;
 127                goto fail1;
 128        }
 129
 130        pinexio->serio = serio;
 131        pinexio->dev = input_dev;
 132        snprintf(pinexio->phys, sizeof(pinexio->phys), "%s/input0", serio->phys);
 133
 134        input_dev->name = "iNexio Serial TouchScreen";
 135        input_dev->phys = pinexio->phys;
 136        input_dev->id.bustype = BUS_RS232;
 137        input_dev->id.vendor = SERIO_INEXIO;
 138        input_dev->id.product = 0;
 139        input_dev->id.version = 0x0001;
 140        input_dev->dev.parent = &serio->dev;
 141        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 142        input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 143        input_set_abs_params(pinexio->dev, ABS_X, INEXIO_MIN_XC, INEXIO_MAX_XC, 0, 0);
 144        input_set_abs_params(pinexio->dev, ABS_Y, INEXIO_MIN_YC, INEXIO_MAX_YC, 0, 0);
 145
 146        serio_set_drvdata(serio, pinexio);
 147
 148        err = serio_open(serio, drv);
 149        if (err)
 150                goto fail2;
 151
 152        err = input_register_device(pinexio->dev);
 153        if (err)
 154                goto fail3;
 155
 156        return 0;
 157
 158 fail3: serio_close(serio);
 159 fail2: serio_set_drvdata(serio, NULL);
 160 fail1: input_free_device(input_dev);
 161        kfree(pinexio);
 162        return err;
 163}
 164
 165/*
 166 * The serio driver structure.
 167 */
 168
 169static struct serio_device_id inexio_serio_ids[] = {
 170        {
 171                .type   = SERIO_RS232,
 172                .proto  = SERIO_INEXIO,
 173                .id     = SERIO_ANY,
 174                .extra  = SERIO_ANY,
 175        },
 176        { 0 }
 177};
 178
 179MODULE_DEVICE_TABLE(serio, inexio_serio_ids);
 180
 181static struct serio_driver inexio_drv = {
 182        .driver         = {
 183                .name   = "inexio",
 184        },
 185        .description    = DRIVER_DESC,
 186        .id_table       = inexio_serio_ids,
 187        .interrupt      = inexio_interrupt,
 188        .connect        = inexio_connect,
 189        .disconnect     = inexio_disconnect,
 190};
 191
 192module_serio_driver(inexio_drv);
 193