/*
* Fujitsu serial touchscreen driver
*
* Copyright (c) Dmitry Torokhov <dtor@mail.ru>
*/
/*
* 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.
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/serio.h>
#define DRIVER_DESC "Fujitsu serial touchscreen driver"
MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
#define FUJITSU_LENGTH 5
/*
* Per-touchscreen data.
*/
struct fujitsu {
struct input_dev *dev;
struct serio *serio;
int idx;
unsigned char data[FUJITSU_LENGTH];
char phys[32];
};
/*
* Decode serial data (5 bytes per packet)
* First byte
* 1 C 0 0 R S S S
* Where C is 1 while in calibration mode (which we don't use)
* R is 1 when no coordinate corection was done.
* S are button state
*/
static irqreturn_t fujitsu_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct fujitsu *fujitsu = serio_get_drvdata(serio);
struct input_dev *dev = fujitsu->dev;
if (fujitsu->idx == 0) {
/* resync skip until start of frame */
if ((data & 0xf0) != 0x80)
return IRQ_HANDLED;
} else {
/* resync skip garbage */
if (data & 0x80) {
fujitsu->idx = 0;
return IRQ_HANDLED;
}
}
fujitsu->data[fujitsu->idx++] = data;
if (fujitsu->idx == FUJITSU_LENGTH) {
input_report_abs(dev, ABS_X,
(fujitsu->data[2] << 7) | fujitsu->data[1]);
input_report_abs(dev, ABS_Y,
(fujitsu->data[4] << 7) | fujitsu->data[3]);
input_report_key(dev, BTN_TOUCH,
(fujitsu->data[0] & 0x03) != 2);
input_sync(dev);
fujitsu->idx = 0;
}
return IRQ_HANDLED;
}
/*
* fujitsu_disconnect() is the opposite of fujitsu_connect()
*/
static void fujitsu_disconnect(struct serio *serio)
{
struct fujitsu *fujitsu = serio_get_drvdata(serio);
input_get_device(fujitsu->dev);
input_unregister_device(fujitsu->dev);
serio_close(serio);
serio_set_drvdata(serio, NULL);
input_put_device(fujitsu->dev);
kfree(fujitsu);
}
/*
* fujitsu_connect() is the routine that is called when someone adds a
* new serio device that supports the Fujitsu protocol and registers it
* as input device.
*/
static int fujitsu_connect(struct serio *serio, struct serio_driver *drv)
{
struct fujitsu *fujitsu;
struct input_dev *input_dev;
int err;
fujitsu = kzalloc(sizeof(struct fujitsu), GFP_KERNEL);
input_dev = input_allocate_device();
if (!fujitsu || !input_dev) {
err = -ENOMEM;
goto fail1;
}
fujitsu->serio = serio;
fujitsu->dev = input_dev;
snprintf(fujitsu->phys, sizeof(fujitsu->phys),
"%s/input0", serio->phys);
input_dev->name = "Fujitsu Serial Touchscreen";
input_dev->phys = fujitsu->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_FUJITSU;
input_dev->id.product = 0;
input_dev->id.version = 0x0100;
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(input_dev, ABS_X, 0, 4096, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 0, 4096, 0, 0);
serio_set_drvdata(serio, fujitsu);
err = serio_open(serio, drv);
if (err)
goto fail2;
err = input_register_device(fujitsu->dev);
if (err)
goto fail3;
return 0;
fail3:
serio_close(serio);
fail2:
serio_set_drvdata(serio, NULL);
fail1:
input_free_device(input_dev);
kfree(fujitsu);
return err;
}
/*
* The serio driver structure.
*/
static struct serio_device_id fujitsu_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_FUJITSU,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, fujitsu_serio_ids);
static struct serio_driver fujitsu_drv = {
.driver = {
.name = "fujitsu_ts",
},
.description = DRIVER_DESC,
.id_table = fujitsu_serio_ids,
.interrupt = fujitsu_interrupt,
.connect = fujitsu_connect,
.disconnect = fujitsu_disconnect,
};
module_serio_driver(fujitsu_drv);
