dynapro.c

Go to the documentation of this file.

/*
 * Dynapro serial touchscreen driver
 *
 * Copyright (c) 2009 Tias Guns
 * Based on the inexio driver (c) Vojtech Pavlik and Dan Streetman and
 * Richard Lemon
 *
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

/*
 * 2009/09/19 Tias Guns <[email protected]>
 *   Copied inexio.c and edited for Dynapro protocol (from retired Xorg module)
 */

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/init.h>

#define DRIVER_DESC "Dynapro serial touchscreen driver"

MODULE_AUTHOR("Tias Guns <[email protected]>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

/*
 * Definitions & global arrays.
 */

#define DYNAPRO_FORMAT_TOUCH_BIT 0x40
#define DYNAPRO_FORMAT_LENGTH 3
#define DYNAPRO_RESPONSE_BEGIN_BYTE 0x80

#define DYNAPRO_MIN_XC 0
#define DYNAPRO_MAX_XC 0x3ff
#define DYNAPRO_MIN_YC 0
#define DYNAPRO_MAX_YC 0x3ff

#define DYNAPRO_GET_XC(data) (data[1] | ((data[0] & 0x38) << 4))
#define DYNAPRO_GET_YC(data) (data[2] | ((data[0] & 0x07) << 7))
#define DYNAPRO_GET_TOUCHED(data) (DYNAPRO_FORMAT_TOUCH_BIT & data[0])

/*
 * Per-touchscreen data.
 */

struct dynapro {
    struct input_dev *dev;
    struct serio *serio;
    int idx;
    unsigned char data[DYNAPRO_FORMAT_LENGTH];
    char phys[32];
};

static void dynapro_process_data(struct dynapro *pdynapro)
{
    struct input_dev *dev = pdynapro->dev;

    if (DYNAPRO_FORMAT_LENGTH == ++pdynapro->idx) {
        input_report_abs(dev, ABS_X, DYNAPRO_GET_XC(pdynapro->data));
        input_report_abs(dev, ABS_Y, DYNAPRO_GET_YC(pdynapro->data));
        input_report_key(dev, BTN_TOUCH,
                 DYNAPRO_GET_TOUCHED(pdynapro->data));
        input_sync(dev);

        pdynapro->idx = 0;
    }
}

static irqreturn_t dynapro_interrupt(struct serio *serio,
        unsigned char data, unsigned int flags)
{
    struct dynapro *pdynapro = serio_get_drvdata(serio);

    pdynapro->data[pdynapro->idx] = data;

    if (DYNAPRO_RESPONSE_BEGIN_BYTE & pdynapro->data[0])
        dynapro_process_data(pdynapro);
    else
        dev_dbg(&serio->dev, "unknown/unsynchronized data: %x\n",
            pdynapro->data[0]);

    return IRQ_HANDLED;
}

static void dynapro_disconnect(struct serio *serio)
{
    struct dynapro *pdynapro = serio_get_drvdata(serio);

    input_get_device(pdynapro->dev);
    input_unregister_device(pdynapro->dev);
    serio_close(serio);
    serio_set_drvdata(serio, NULL);
    input_put_device(pdynapro->dev);
    kfree(pdynapro);
}

/*
 * dynapro_connect() is the routine that is called when someone adds a
 * new serio device that supports dynapro protocol and registers it as
 * an input device. This is usually accomplished using inputattach.
 */

static int dynapro_connect(struct serio *serio, struct serio_driver *drv)
{
    struct dynapro *pdynapro;
    struct input_dev *input_dev;
    int err;

    pdynapro = kzalloc(sizeof(struct dynapro), GFP_KERNEL);
    input_dev = input_allocate_device();
    if (!pdynapro || !input_dev) {
        err = -ENOMEM;
        goto fail1;
    }

    pdynapro->serio = serio;
    pdynapro->dev = input_dev;
    snprintf(pdynapro->phys, sizeof(pdynapro->phys),
         "%s/input0", serio->phys);

    input_dev->name = "Dynapro Serial TouchScreen";
    input_dev->phys = pdynapro->phys;
    input_dev->id.bustype = BUS_RS232;
    input_dev->id.vendor = SERIO_DYNAPRO;
    input_dev->id.product = 0;
    input_dev->id.version = 0x0001;
    input_dev->dev.parent = &serio->dev;
    input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
    input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
    input_set_abs_params(pdynapro->dev, ABS_X,
                 DYNAPRO_MIN_XC, DYNAPRO_MAX_XC, 0, 0);
    input_set_abs_params(pdynapro->dev, ABS_Y,
                 DYNAPRO_MIN_YC, DYNAPRO_MAX_YC, 0, 0);

    serio_set_drvdata(serio, pdynapro);

    err = serio_open(serio, drv);
    if (err)
        goto fail2;

    err = input_register_device(pdynapro->dev);
    if (err)
        goto fail3;

    return 0;

 fail3: serio_close(serio);
 fail2: serio_set_drvdata(serio, NULL);
 fail1: input_free_device(input_dev);
    kfree(pdynapro);
    return err;
}

/*
 * The serio driver structure.
 */

static struct serio_device_id dynapro_serio_ids[] = {
    {
        .type   = SERIO_RS232,
        .proto  = SERIO_DYNAPRO,
        .id = SERIO_ANY,
        .extra  = SERIO_ANY,
    },
    { 0 }
};

MODULE_DEVICE_TABLE(serio, dynapro_serio_ids);

static struct serio_driver dynapro_drv = {
    .driver     = {
        .name   = "dynapro",
    },
    .description    = DRIVER_DESC,
    .id_table   = dynapro_serio_ids,
    .interrupt  = dynapro_interrupt,
    .connect    = dynapro_connect,
    .disconnect = dynapro_disconnect,
};

module_serio_driver(dynapro_drv);