/*
 *  Copyright (c) 2008 Néstor Amigo Cairo, based on
 *  Copyright (c) 2000 Justin Cormack
 */

/*
 * Samko encoder driver for Linux
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Should you need to contact me, the author, you can do so by
 * e-mail - mail your message to <nestorac@gmail.com>.
 */

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

#define DRIVER_DESC	"Samko Serial Encoder controller device input driver"

MODULE_AUTHOR("Néstor Amigo Cairo <nestorac@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

#define SERIO_SAM    0x36
#define BIT_MASK(nr)            (1UL << ((nr) % BITS_PER_LONG))


static unsigned char nkbd_keycode[256] = {
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1
};

struct nkbd {
	unsigned char keycode[256];
	struct input_dev *dev;
	struct serio *serio;
	char phys[32];
};

static irqreturn_t nkbd_interrupt(struct serio *serio,
		unsigned char data, unsigned int flags)
{
	struct nkbd *nkbd = serio_get_drvdata(serio);

	/* invalid scan codes are probably the init sequence, so we ignore them */
	//if (nkbd->keycode[data]) {
	  if ((int)data == 217) // Then, left key is pressed
	  {
	    input_report_key(nkbd->dev, KEY_LEFTSHIFT, 1);
	    input_report_key(nkbd->dev, KEY_TAB, 1);
	    input_report_key(nkbd->dev, KEY_TAB, 0);
	    input_report_key(nkbd->dev, KEY_LEFTSHIFT, 0);
	    input_sync(nkbd->dev);
		  printk(KERN_INFO "Samko's Left Key: 96\n");
	  }
	  else if ((int)data == 200) // Then, center key is pressed
	  {
	    input_report_key(nkbd->dev, KEY_A, 1);
	    input_report_key(nkbd->dev, KEY_A, 0);
	    input_sync(nkbd->dev);
		  printk(KERN_INFO "Samko's Center Key: 32\n");
	  }
	  else if ((int)data == 208) // Then, right key is pressed
	  {
	    input_report_key(nkbd->dev, KEY_TAB, 1);
	    input_report_key(nkbd->dev, KEY_TAB, 0);
	    input_sync(nkbd->dev);
		  printk(KERN_INFO "Samko's Right Key: 80\n");
	  }
	  else
	  {
	    printk(KERN_INFO "Samko's Key pressed: %i\n",(int)data);
	  }
	//}
	//else if (data == 0xe7) /* end of init sequence */
	//	printk(KERN_INFO "input: %s on %s\n", nkbd->dev->name, serio->phys);
	//else
	//{
	//  printk(KERN_INFO "Samko's Key pressed (other situation): %i\n",(int)data);
	//}
	return IRQ_HANDLED;
}

static int nkbd_connect(struct serio *serio, struct serio_driver *drv)
{
	struct nkbd *nkbd;
	struct input_dev *input_dev;
	int err = -ENOMEM;
	int i;

	nkbd = kzalloc(sizeof(struct nkbd), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!nkbd || !input_dev)
		goto fail1;

	nkbd->serio = serio;
	nkbd->dev = input_dev;
	snprintf(nkbd->phys, sizeof(nkbd->phys), "%s/input0", serio->phys);
	memcpy(nkbd->keycode, nkbd_keycode, sizeof(nkbd->keycode));

	input_dev->name = "Samko Serial Encoder Device";
	input_dev->phys = nkbd->phys;
	input_dev->id.bustype = BUS_RS232;
	input_dev->id.vendor = SERIO_SAM;
	input_dev->id.product = 0x0001;
	input_dev->id.version = 0x0100;
	input_dev->dev.parent = &serio->dev;

	input_dev->evbit[0] = BIT_MASK(EV_KEY);
	input_dev->keycode = nkbd->keycode;
	input_dev->keycodesize = sizeof(unsigned char);
	input_dev->keycodemax = sizeof(nkbd_keycode);
	for (i = 0; i < 255; i++)
		set_bit(nkbd->keycode[i], input_dev->keybit);
	clear_bit(0, input_dev->keybit);

	serio_set_drvdata(serio, nkbd);

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

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

	return 0;

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

static void nkbd_disconnect(struct serio *serio)
{
	struct nkbd *nkbd = serio_get_drvdata(serio);

	serio_close(serio);
	serio_set_drvdata(serio, NULL);
	input_unregister_device(nkbd->dev);
	kfree(nkbd);
}

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

MODULE_DEVICE_TABLE(serio, nkbd_serio_ids);

static struct serio_driver nkbd_drv = {
	.driver		= {
		.name	= "serenc",
	},
	.description	= DRIVER_DESC,
	.id_table	= nkbd_serio_ids,
	.interrupt	= nkbd_interrupt,
	.connect	= nkbd_connect,
	.disconnect	= nkbd_disconnect,
	//.write = tty_write,
};

static int __init nkbd_init(void)
{
	return serio_register_driver(&nkbd_drv);
}

static void __exit nkbd_exit(void)
{
	serio_unregister_driver(&nkbd_drv);
}

module_init(nkbd_init);
module_exit(nkbd_exit);