/*
 * Allegro A8293 SEC driver
 *
 * Copyright (C) 2011 Antti Palosaari <crope@iki.fi>
 *
 *    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.
 */

#include "a8293.h"

struct a8293_dev {
	struct i2c_client *client;
	u8 reg[2];
};

static int a8293_set_voltage(struct dvb_frontend *fe,
			     enum fe_sec_voltage fe_sec_voltage)
{
	struct a8293_dev *dev = fe->sec_priv;
	struct i2c_client *client = dev->client;
	int ret;
	u8 reg0, reg1;

	dev_dbg(&client->dev, "fe_sec_voltage=%d\n", fe_sec_voltage);

	switch (fe_sec_voltage) {
	case SEC_VOLTAGE_OFF:
		/* ENB=0 */
		reg0 = 0x10;
		break;
	case SEC_VOLTAGE_13:
		/* VSEL0=1, VSEL1=0, VSEL2=0, VSEL3=0, ENB=1*/
		reg0 = 0x31;
		break;
	case SEC_VOLTAGE_18:
		/* VSEL0=0, VSEL1=0, VSEL2=0, VSEL3=1, ENB=1*/
		reg0 = 0x38;
		break;
	default:
		ret = -EINVAL;
		goto err;
	}
	if (reg0 != dev->reg[0]) {
		ret = i2c_master_send(client, &reg0, 1);
		if (ret < 0)
			goto err;
		dev->reg[0] = reg0;
	}

	/* TMODE=0, TGATE=1 */
	reg1 = 0x82;
	if (reg1 != dev->reg[1]) {
		ret = i2c_master_send(client, &reg1, 1);
		if (ret < 0)
			goto err;
		dev->reg[1] = reg1;
	}

	usleep_range(1500, 50000);
	return 0;
err:
	dev_dbg(&client->dev, "failed=%d\n", ret);
	return ret;
}

static int a8293_probe(struct i2c_client *client,
		       const struct i2c_device_id *id)
{
	struct a8293_dev *dev;
	struct a8293_platform_data *pdata = client->dev.platform_data;
	struct dvb_frontend *fe = pdata->dvb_frontend;
	int ret;
	u8 buf[2];

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev) {
		ret = -ENOMEM;
		goto err;
	}

	dev->client = client;

	/* check if the SEC is there */
	ret = i2c_master_recv(client, buf, 2);
	if (ret < 0)
		goto err_kfree;

	/* override frontend ops */
	fe->ops.set_voltage = a8293_set_voltage;
	fe->sec_priv = dev;
	i2c_set_clientdata(client, dev);

	dev_info(&client->dev, "Allegro A8293 SEC successfully attached\n");
	return 0;
err_kfree:
	kfree(dev);
err:
	dev_dbg(&client->dev, "failed=%d\n", ret);
	return ret;
}

static int a8293_remove(struct i2c_client *client)
{
	struct a8293_dev *dev = i2c_get_clientdata(client);

	dev_dbg(&client->dev, "\n");

	kfree(dev);
	return 0;
}

static const struct i2c_device_id a8293_id_table[] = {
	{"a8293", 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, a8293_id_table);

static struct i2c_driver a8293_driver = {
	.driver = {
		.name	= "a8293",
		.suppress_bind_attrs = true,
	},
	.probe		= a8293_probe,
	.remove		= a8293_remove,
	.id_table	= a8293_id_table,
};

module_i2c_driver(a8293_driver);

MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
MODULE_DESCRIPTION("Allegro A8293 SEC driver");
MODULE_LICENSE("GPL");