path: root/drivers/media/dvb/frontends/hd29l2.c

/*
 * HDIC HD29L2 DMB-TH demodulator driver
 *
 * Copyright (C) 2011 Metropolia University of Applied Sciences, Electria R&D
 *
 * Author: 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.
 *
 *    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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "hd29l2_priv.h"

int hd29l2_debug;
module_param_named(debug, hd29l2_debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

/* write multiple registers */
static int hd29l2_wr_regs(struct hd29l2_priv *priv, u8 reg, u8 *val, int len)
{
	int ret;
	u8 buf[2+len];
	struct i2c_msg msg[1] = {
		{
			.addr = priv->cfg.i2c_addr,
			.flags = 0,
			.len = sizeof(buf),
			.buf = buf,
		}
	};

	buf[0] = 0x00;
	buf[1] = reg;
	memcpy(&buf[2], val, len);

	ret = i2c_transfer(priv->i2c, msg, 1);
	if (ret == 1) {
		ret = 0;
	} else {
		warn("i2c wr failed=%d reg=%02x len=%d", ret, reg, len);
		ret = -EREMOTEIO;
	}

	return ret;
}

/* read multiple registers */
static int hd29l2_rd_regs(struct hd29l2_priv *priv, u8 reg, u8 *val, int len)
{
	int ret;
	u8 buf[2] = { 0x00, reg };
	struct i2c_msg msg[2] = {
		{
			.addr = priv->cfg.i2c_addr,
			.flags = 0,
			.len = 2,
			.buf = buf,
		}, {
			.addr = priv->cfg.i2c_addr,
			.flags = I2C_M_RD,
			.len = len,
			.buf = val,
		}
	};

	ret = i2c_transfer(priv->i2c, msg, 2);
	if (ret == 2) {
		ret = 0;
	} else {
		warn("i2c rd failed=%d reg=%02x len=%d", ret, reg, len);
		ret = -EREMOTEIO;
	}

	return ret;
}

/* write single register */
static int hd29l2_wr_reg(struct hd29l2_priv *priv, u8 reg, u8 val)
{
	return hd29l2_wr_regs(priv, reg, &val, 1);
}

/* read single register */
static int hd29l2_rd_reg(struct hd29l2_priv *priv, u8 reg, u8 *val)
{
	return hd29l2_rd_regs(priv, reg, val, 1);
}

/* write single register with mask */
static int hd29l2_wr_reg_mask(struct hd29l2_priv *priv, u8 reg, u8 val, u8 mask)
{
	int ret;
	u8 tmp;

	/* no need for read if whole reg is written */
	if (mask != 0xff) {
		ret = hd29l2_rd_regs(priv, reg, &tmp, 1);
		if (ret)
			return ret;

		val &= mask;
		tmp &= ~mask;
		val |= tmp;
	}

	return hd29l2_wr_regs(priv, reg, &val, 1);
}

/* read single register with mask */
int hd29l2_rd_reg_mask(struct hd29l2_priv *priv, u8 reg, u8 *val, u8 mask)
{
	int ret, i;
	u8 tmp;

	ret = hd29l2_rd_regs(priv, reg, &tmp, 1);
	if (ret)
		return ret;

	tmp &= mask;

	/* find position of the first bit */
	for (i = 0; i < 8; i++) {
		if ((mask >> i) & 0x01)
			break;
	}
	*val = tmp >> i;

	return 0;
}

static int hd29l2_soft_reset(struct hd29l2_priv *priv)
{
	int ret;
	u8 tmp;

	ret = hd29l2_rd_reg(priv, 0x26, &tmp);
	if (ret)
		goto err;

	ret = hd29l2_wr_reg(priv, 0x26, 0x0d);
	if (ret)
		goto err;

	usleep_range(10000, 20000);

	ret = hd29l2_wr_reg(priv, 0x26, tmp);
	if (ret)
		goto err;

	return 0;
err:
	dbg("%s: failed=%d", __func__, ret);
	return ret;
}

static int hd29l2_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
{
	int ret, i;
	struct hd29l2_priv *priv = fe->demodulator_priv;
	u8 tmp;

	dbg("%s: enable=%d", __func__, enable);

	/* set tuner address for demod */
	if (!</