inexio.c
/*
* iNexio serial touchscreen driver
*
* Copyright (c) 2008 Richard Lemon
* Based on the mtouch driver (c) Vojtech Pavlik and Dan Streetman
*
*/
/*
* 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.
*/
/*
* 2008/06/19 Richard Lemon <richard@codelemon.com>
* Copied mtouch.c and edited for iNexio protocol
*/
#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 "iNexio serial touchscreen driver"
MODULE_AUTHOR("Richard Lemon <richard@codelemon.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
/*
* Definitions & global arrays.
*/
#define INEXIO_FORMAT_TOUCH_BIT 0x01
#define INEXIO_FORMAT_LENGTH 5
#define INEXIO_RESPONSE_BEGIN_BYTE 0x80
/* todo: check specs for max length of all responses */
#define INEXIO_MAX_LENGTH 16
#define INEXIO_MIN_XC 0
#define INEXIO_MAX_XC 0x3fff
#define INEXIO_MIN_YC 0
#define INEXIO_MAX_YC 0x3fff
#define INEXIO_GET_XC(data) (((data[1])<<7) | data[2])
#define INEXIO_GET_YC(data) (((data[3])<<7) | data[4])
#define INEXIO_GET_TOUCHED(data) (INEXIO_FORMAT_TOUCH_BIT & data[0])
/*
* Per-touchscreen data.
*/
struct inexio {
struct input_dev *dev;
struct serio *serio;
int idx;
unsigned char data[INEXIO_MAX_LENGTH];
char phys[32];
};
static void inexio_process_data(struct inexio *pinexio)
{
struct input_dev *dev = pinexio->dev;
if (INEXIO_FORMAT_LENGTH == ++pinexio->idx) {
input_report_abs(dev, ABS_X, INEXIO_GET_XC(pinexio->data));
input_report_abs(dev, ABS_Y, INEXIO_GET_YC(pinexio->data));
input_report_key(dev, BTN_TOUCH, INEXIO_GET_TOUCHED(pinexio->data));
input_sync(dev);
pinexio->idx = 0;
}
}
static irqreturn_t inexio_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct inexio* pinexio = serio_get_drvdata(serio);
pinexio->data[pinexio->idx] = data;
if (INEXIO_RESPONSE_BEGIN_BYTE&pinexio->data[0])
inexio_process_data(pinexio);
else
printk(KERN_DEBUG "inexio.c: unknown/unsynchronized data from device, byte %x\n",pinexio->data[0]);
return IRQ_HANDLED;
}
/*
* inexio_disconnect() is the opposite of inexio_connect()
*/
static void inexio_disconnect(struct serio *serio)
{
struct inexio* pinexio = serio_get_drvdata(serio);
input_get_device(pinexio->dev);
input_unregister_device(pinexio->dev);
serio_close(serio);
serio_set_drvdata(serio, NULL);
input_put_device(pinexio->dev);
kfree(pinexio);
}
/*
* inexio_connect() is the routine that is called when someone adds a
* new serio device that supports iNexio protocol and registers it as
* an input device. This is usually accomplished using inputattach.
*/
static int inexio_connect(struct serio *serio, struct serio_driver *drv)
{
struct inexio *pinexio;
struct input_dev *input_dev;
int err;
pinexio = kzalloc(sizeof(struct inexio), GFP_KERNEL);
input_dev = input_allocate_device();
if (!pinexio || !input_dev) {
err = -ENOMEM;
goto fail1;
}
pinexio->serio = serio;
pinexio->dev = input_dev;
snprintf(pinexio->phys, sizeof(pinexio->phys), "%s/input0", serio->phys);
input_dev->name = "iNexio Serial TouchScreen";
input_dev->phys = pinexio->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_INEXIO;
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(pinexio->dev, ABS_X, INEXIO_MIN_XC, INEXIO_MAX_XC, 0, 0);
input_set_abs_params(pinexio->dev, ABS_Y, INEXIO_MIN_YC, INEXIO_MAX_YC, 0, 0);
serio_set_drvdata(serio, pinexio);
err = serio_open(serio, drv);
if (err)
goto fail2;
err = input_register_device(pinexio->dev);
if (err)
goto fail3;
return 0;
fail3: serio_close(serio);
fail2: serio_set_drvdata(serio, NULL);
fail1: input_free_device(input_dev);
kfree(pinexio);
return err;
}
/*
* The serio driver structure.
*/
static struct serio_device_id inexio_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_INEXIO,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, inexio_serio_ids);
static struct serio_driver inexio_drv = {
.driver = {
.name = "inexio",
},
.description = DRIVER_DESC,
.id_table = inexio_serio_ids,
.interrupt = inexio_interrupt,
.connect = inexio_connect,
.disconnect = inexio_disconnect,
};
module_serio_driver(inexio_drv);