Linux-2.6.12-rc2

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / media / video / saa5246a.c

/*
 * Driver for the SAA5246A or SAA5281 Teletext (=Videotext) decoder chips from
 * Philips.
 *
 * Only capturing of Teletext pages is tested. The videotext chips also have a
 * TV output but my hardware doesn't use it. For this reason this driver does
 * not support changing any TV display settings.
 *
 * Copyright (C) 2004 Michael Geng <linux@MichaelGeng.de>
 *
 * Derived from
 *
 * saa5249 driver
 * Copyright (C) 1998 Richard Guenther
 * <richard.guenther@student.uni-tuebingen.de>
 *
 * with changes by
 * Alan Cox <Alan.Cox@linux.org>
 *
 * and
 *
 * vtx.c
 * Copyright (C) 1994-97 Martin Buck  <martin-2.buck@student.uni-ulm.de>
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/videotext.h>
#include <linux/videodev.h>
#include "saa5246a.h"

MODULE_AUTHOR("Michael Geng <linux@MichaelGeng.de>");
MODULE_DESCRIPTION("Philips SAA5246A, SAA5281 Teletext decoder driver");
MODULE_LICENSE("GPL");

struct saa5246a_device
{
	u8     pgbuf[NUM_DAUS][VTX_VIRTUALSIZE];
	int    is_searching[NUM_DAUS];
	struct i2c_client *client;
	struct semaphore lock;
};

static struct video_device saa_template;	/* Declared near bottom */

/* Addresses to scan */
static unsigned short normal_i2c[]	 = { I2C_ADDRESS, I2C_CLIENT_END };
static unsigned short normal_i2c_range[] = { I2C_CLIENT_END };
I2C_CLIENT_INSMOD;

static struct i2c_client client_template;

static int saa5246a_attach(struct i2c_adapter *adap, int addr, int kind)
{
	int pgbuf;
	int err;
	struct i2c_client *client;
	struct video_device *vd;
	struct saa5246a_device *t;

	printk(KERN_INFO "saa5246a: teletext chip found.\n");
	client=kmalloc(sizeof(*client), GFP_KERNEL);
	if(client==NULL)
		return -ENOMEM;
	client_template.adapter = adap;
	client_template.addr = addr;
	memcpy(client, &client_template, sizeof(*client));
	t = kmalloc(sizeof(*t), GFP_KERNEL);
	if(t==NULL)
	{
		kfree(client);
		return -ENOMEM;
	}
	memset(t, 0, sizeof(*t));
	strlcpy(client->name, IF_NAME, I2C_NAME_SIZE);
	init_MUTEX(&t->lock);

	/*
	 *	Now create a video4linux device
	 */

	vd = video_device_alloc();
	if(vd==NULL)
	{
		kfree(t);
		kfree(client);
		return -ENOMEM;
	}
	i2c_set_clientdata(client, vd);
	memcpy(vd, &saa_template, sizeof(*vd));

	for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++)
	{
		memset(t->pgbuf[pgbuf], ' ', sizeof(t->pgbuf[0]));
		t->is_searching[pgbuf] = FALSE;
	}
	vd->priv=t;


	/*
	 *	Register it
	 */

	if((err=video_register_device(vd, VFL_TYPE_VTX,-1))<0)
	{
		kfree(t);
		kfree(client);
		video_device_release(vd);
		return err;
	}
	t->client = client;
	i2c_attach_client(client);
	return 0;
}

/*
 *	We do most of the hard work when we become a device on the i2c.
 */
static int saa5246a_probe(struct i2c_adapter *adap)
{
	if (adap->class & I2C_CLASS_TV_ANALOG)
		return i2c_probe(adap, &addr_data, saa5246a_attach);
	return 0;
}

static int saa5246a_detach(struct i2c_client *client)
{
	struct video_device *vd = i2c_get_clientdata(client);
	i2c_detach_client(client);
	video_unregister_device(vd);
	kfree(vd->priv);
	kfree(client);
	return 0;
}

static int saa5246a_command(struct i2c_client *device, unsigned int cmd,
	void *arg)
{
	return -EINVAL;
}

/*
 *	I2C interfaces
 */

static struct i2c_driver i2c_driver_videotext =
{
	.owner 		= THIS_MODULE,
	.name 		= IF_NAME,		/* name */
	.id 		= I2C_DRIVERID_SAA5249, /* in i2c.h */
	.flags 		= I2C_DF_NOTIFY,
	.attach_adapter = saa5246a_probe,
	.detach_client  = saa5246a_detach,
	.command 	= saa5246a_command
};

static struct i2c_client client_template = {
	.driver		= &i2c_driver_videotext,
	.name		= "(unset)",
};

static int i2c_sendbuf(struct saa5246a_device *t, int reg, int count, u8 *data)
{
	char buf[64];

	buf[0] = reg;
	memcpy(buf+1, data, count);

	if(i2c_master_send(t->client, buf, count+1)==count+1)
		return 0;
	return -1;
}

static int i2c_senddata(struct saa5246a_device *t, ...)
{
	unsigned char buf[64];
	int v;
	int ct=0;
	va_list argp;
	va_start(argp,t);

	while((v=va_arg(argp,int))!=-1)
		buf[ct++]=v;
	return i2c_sendbuf(t, buf[0], ct-1, buf+1);
}