drivers/media/tuners/tda18218.c - kernel/bruno - Git at Google

 /*
  * NXP TDA18218HN silicon tuner driver
  *
  * Copyright (C) 2010 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 "tda18218_priv.h"

 /* Max transfer size done by I2C transfer functions */
 #define MAX_XFER_SIZE  64

 /* write multiple registers */
 static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
 {
 	int ret = 0, len2, remaining;
 	u8 buf[MAX_XFER_SIZE];
 	struct i2c_msg msg[1] = {
 		{
 			.addr = priv->cfg->i2c_address,
 			.flags = 0,
 			.buf = buf,
 		}
 	};

 	if (1 + len > sizeof(buf)) {
 		dev_warn(&priv->i2c->dev,
 			 "%s: i2c wr reg=%04x: len=%d is too big!\n",
 			 KBUILD_MODNAME, reg, len);
 		return -EINVAL;
 	}

 	for (remaining = len; remaining > 0;
 			remaining -= (priv->cfg->i2c_wr_max - 1)) {
 		len2 = remaining;
 		if (len2 > (priv->cfg->i2c_wr_max - 1))
 			len2 = (priv->cfg->i2c_wr_max - 1);

 		msg[0].len = 1 + len2;
 		buf[0] = reg + len - remaining;
 		memcpy(&buf[1], &val[len - remaining], len2);

 		ret = i2c_transfer(priv->i2c, msg, 1);
 		if (ret != 1)
 			break;
 	}

 	if (ret == 1) {
 		ret = 0;
 	} else {
 		dev_warn(&priv->i2c->dev, "%s: i2c wr failed=%d reg=%02x " \
 				"len=%d\n", KBUILD_MODNAME, ret, reg, len);
 		ret = -EREMOTEIO;
 	}

 	return ret;
 }

 /* read multiple registers */
 static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
 {
 	int ret;
 	u8 buf[MAX_XFER_SIZE]; /* we must start read always from reg 0x00 */
 	struct i2c_msg msg[2] = {
 		{
 			.addr = priv->cfg->i2c_address,
 			.flags = 0,
 			.len = 1,
 			.buf = "\x00",
 		}, {
 			.addr = priv->cfg->i2c_address,
 			.flags = I2C_M_RD,
 			.len = reg + len,
 			.buf = buf,
 		}
 	};

 	if (reg + len > sizeof(buf)) {
 		dev_warn(&priv->i2c->dev,
 			 "%s: i2c wr reg=%04x: len=%d is too big!\n",
 			 KBUILD_MODNAME, reg, len);
 		return -EINVAL;
 	}

 	ret = i2c_transfer(priv->i2c, msg, 2);
 	if (ret == 2) {
 		memcpy(val, &buf[reg], len);
 		ret = 0;
 	} else {
 		dev_warn(&priv->i2c->dev, "%s: i2c rd failed=%d reg=%02x " \
 				"len=%d\n", KBUILD_MODNAME, ret, reg, len);
 		ret = -EREMOTEIO;
 	}

 	return ret;
 }

 /* write single register */
 static int tda18218_wr_reg(struct tda18218_priv *priv, u8 reg, u8 val)
 {
 	return tda18218_wr_regs(priv, reg, &val, 1);
 }

 /* read single register */

 static int tda18218_rd_reg(struct tda18218_priv *priv, u8 reg, u8 *val)
 {
 	return tda18218_rd_regs(priv, reg, val, 1);
 }

 static int tda18218_set_params(struct dvb_frontend *fe)
 {
 	struct tda18218_priv *priv = fe->tuner_priv;
 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 	u32 bw = c->bandwidth_hz;
 	int ret;
 	u8 buf[3], i, BP_Filter, LP_Fc;
 	u32 LO_Frac;
 	/* TODO: find out correct AGC algorithm */
 	u8 agc[][2] = {
 		{ R20_AGC11, 0x60 },
 		{ R23_AGC21, 0x02 },
 		{ R20_AGC11, 0xa0 },
 		{ R23_AGC21, 0x09 },
 		{ R20_AGC11, 0xe0 },
 		{ R23_AGC21, 0x0c },
 		{ R20_AGC11, 0x40 },
 		{ R23_AGC21, 0x01 },
 		{ R20_AGC11, 0x80 },
 		{ R23_AGC21, 0x08 },
 		{ R20_AGC11, 0xc0 },
 		{ R23_AGC21, 0x0b },
 		{ R24_AGC22, 0x1c },
 		{ R24_AGC22, 0x0c },
 	};

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

 	/* low-pass filter cut-off frequency */
 	if (bw <= 6000000) {
 		LP_Fc = 0;
 		priv->if_frequency = 3000000;
 	} else if (bw <= 7000000) {
 		LP_Fc = 1;
 		priv->if_frequency = 3500000;
 	} else {
 		LP_Fc = 2;
 		priv->if_frequency = 4000000;
 	}

 	LO_Frac = c->frequency + priv->if_frequency;

 	/* band-pass filter */
 	if (LO_Frac < 188000000)
 		BP_Filter = 3;
 	else if (LO_Frac < 253000000)
 		BP_Filter = 4;
 	else if (LO_Frac < 343000000)
 		BP_Filter = 5;
 	else
 		BP_Filter = 6;

 	buf[0] = (priv->regs[R1A_IF1] & ~7) | BP_Filter; /* BP_Filter */
 	buf[1] = (priv->regs[R1B_IF2] & ~3) | LP_Fc; /* LP_Fc */
 	buf[2] = priv->regs[R1C_AGC2B];
 	ret = tda18218_wr_regs(priv, R1A_IF1, buf, 3);
 	if (ret)
 		goto error;

 	buf[0] = (LO_Frac / 1000) >> 12; /* LO_Frac_0 */
 	buf[1] = (LO_Frac / 1000) >> 4; /* LO_Frac_1 */
 	buf[2] = (LO_Frac / 1000) << 4 |
 		(priv->regs[R0C_MD5] & 0x0f); /* LO_Frac_2 */
 	ret = tda18218_wr_regs(priv, R0A_MD3, buf, 3);
 	if (ret)
 		goto error;

 	buf[0] = priv->regs[R0F_MD8] | (1 << 6); /* Freq_prog_Start */
 	ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
 	if (ret)
 		goto error;

 	buf[0] = priv->regs[R0F_MD8] & ~(1 << 6); /* Freq_prog_Start */
 	ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
 	if (ret)
 		goto error;

 	/* trigger AGC */
 	for (i = 0; i < ARRAY_SIZE(agc); i++) {
 		ret = tda18218_wr_reg(priv, agc[i][0], agc[i][1]);
 		if (ret)
 			goto error;
 	}

 error:
 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

 	if (ret)
 		dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

 	return ret;
 }

 static int tda18218_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
 {
 	struct tda18218_priv *priv = fe->tuner_priv;
 	*frequency = priv->if_frequency;
 	dev_dbg(&priv->i2c->dev, "%s: if_frequency=%d\n", __func__, *frequency);
 	return 0;
 }

 static int tda18218_sleep(struct dvb_frontend *fe)
 {
 	struct tda18218_priv *priv = fe->tuner_priv;
 	int ret;

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

 	/* standby */
 	ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

 	if (ret)
 		dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

 	return ret;
 }

 static int tda18218_init(struct dvb_frontend *fe)
 {
 	struct tda18218_priv *priv = fe->tuner_priv;
 	int ret;

 	/* TODO: calibrations */

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

 	ret = tda18218_wr_regs(priv, R00_ID, priv->regs, TDA18218_NUM_REGS);

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

 	if (ret)
 		dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

 	return ret;
 }

 static int tda18218_release(struct dvb_frontend *fe)
 {
 	kfree(fe->tuner_priv);
 	fe->tuner_priv = NULL;
 	return 0;
 }

 static const struct dvb_tuner_ops tda18218_tuner_ops = {
 	.info = {
 		.name           = "NXP TDA18218",

 		.frequency_min  = 174000000,
 		.frequency_max  = 864000000,
 		.frequency_step =      1000,
 	},

 	.release       = tda18218_release,
 	.init          = tda18218_init,
 	.sleep         = tda18218_sleep,

 	.set_params    = tda18218_set_params,

 	.get_if_frequency = tda18218_get_if_frequency,
 };

 struct dvb_frontend *tda18218_attach(struct dvb_frontend *fe,
 	struct i2c_adapter *i2c, struct tda18218_config *cfg)
 {
 	struct tda18218_priv *priv = NULL;
 	u8 val;
 	int ret;
 	/* chip default registers values */
 	static u8 def_regs[] = {
 		0xc0, 0x88, 0x00, 0x8e, 0x03, 0x00, 0x00, 0xd0, 0x00, 0x40,
 		0x00, 0x00, 0x07, 0xff, 0x84, 0x09, 0x00, 0x13, 0x00, 0x00,
 		0x01, 0x84, 0x09, 0xf0, 0x19, 0x0a, 0x8e, 0x69, 0x98, 0x01,
 		0x00, 0x58, 0x10, 0x40, 0x8c, 0x00, 0x0c, 0x48, 0x85, 0xc9,
 		0xa7, 0x00, 0x00, 0x00, 0x30, 0x81, 0x80, 0x00, 0x39, 0x00,
 		0x8a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf6, 0xf6
 	};

 	priv = kzalloc(sizeof(struct tda18218_priv), GFP_KERNEL);
 	if (priv == NULL)
 		return NULL;

 	priv->cfg = cfg;
 	priv->i2c = i2c;
 	fe->tuner_priv = priv;

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

 	/* check if the tuner is there */
 	ret = tda18218_rd_reg(priv, R00_ID, &val);
 	if (!ret)
 		dev_dbg(&priv->i2c->dev, "%s: chip id=%02x\n", __func__, val);
 	if (ret || val != def_regs[R00_ID]) {
 		kfree(priv);
 		return NULL;
 	}

 	dev_info(&priv->i2c->dev,
 			"%s: NXP TDA18218HN successfully identified\n",
 			KBUILD_MODNAME);

 	memcpy(&fe->ops.tuner_ops, &tda18218_tuner_ops,
 		sizeof(struct dvb_tuner_ops));
 	memcpy(priv->regs, def_regs, sizeof(def_regs));

 	/* loop-through enabled chip default register values */
 	if (priv->cfg->loop_through) {
 		priv->regs[R17_PD1] = 0xb0;
 		priv->regs[R18_PD2] = 0x59;
 	}

 	/* standby */
 	ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));
 	if (ret)
 		dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

 	return fe;
 }
 EXPORT_SYMBOL(tda18218_attach);

 MODULE_DESCRIPTION("NXP TDA18218HN silicon tuner driver");
 MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
 MODULE_LICENSE("GPL");
	/*
	* NXP TDA18218HN silicon tuner driver
	*
	* Copyright (C) 2010 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 "tda18218_priv.h"

	/* Max transfer size done by I2C transfer functions */
	#define MAX_XFER_SIZE 64

	/* write multiple registers */
	static int tda18218_wr_regs(struct tda18218_priv priv, u8 reg, u8 val, u8 len)
	{
	int ret = 0, len2, remaining;
	u8 buf[MAX_XFER_SIZE];
	struct i2c_msg msg[1] = {
	{
	.addr = priv->cfg->i2c_address,
	.flags = 0,
	.buf = buf,
	}
	};

	if (1 + len > sizeof(buf)) {
	dev_warn(&priv->i2c->dev,
	"%s: i2c wr reg=%04x: len=%d is too big!\n",
	KBUILD_MODNAME, reg, len);
	return -EINVAL;
	}

	for (remaining = len; remaining > 0;
	remaining -= (priv->cfg->i2c_wr_max - 1)) {
	len2 = remaining;
	if (len2 > (priv->cfg->i2c_wr_max - 1))
	len2 = (priv->cfg->i2c_wr_max - 1);

	msg[0].len = 1 + len2;
	buf[0] = reg + len - remaining;
	memcpy(&buf[1], &val[len - remaining], len2);

	ret = i2c_transfer(priv->i2c, msg, 1);
	if (ret != 1)
	break;
	}

	if (ret == 1) {
	ret = 0;
	} else {
	dev_warn(&priv->i2c->dev, "%s: i2c wr failed=%d reg=%02x " \
	"len=%d\n", KBUILD_MODNAME, ret, reg, len);
	ret = -EREMOTEIO;
	}

	return ret;
	}

	/* read multiple registers */
	static int tda18218_rd_regs(struct tda18218_priv priv, u8 reg, u8 val, u8 len)
	{
	int ret;
	u8 buf[MAX_XFER_SIZE]; /* we must start read always from reg 0x00 */
	struct i2c_msg msg[2] = {
	{
	.addr = priv->cfg->i2c_address,
	.flags = 0,
	.len = 1,
	.buf = "\x00",
	}, {
	.addr = priv->cfg->i2c_address,
	.flags = I2C_M_RD,
	.len = reg + len,
	.buf = buf,
	}
	};

	if (reg + len > sizeof(buf)) {
	dev_warn(&priv->i2c->dev,
	"%s: i2c wr reg=%04x: len=%d is too big!\n",
	KBUILD_MODNAME, reg, len);
	return -EINVAL;
	}

	ret = i2c_transfer(priv->i2c, msg, 2);
	if (ret == 2) {
	memcpy(val, &buf[reg], len);
	ret = 0;
	} else {
	dev_warn(&priv->i2c->dev, "%s: i2c rd failed=%d reg=%02x " \
	"len=%d\n", KBUILD_MODNAME, ret, reg, len);
	ret = -EREMOTEIO;
	}

	return ret;
	}

	/* write single register */
	static int tda18218_wr_reg(struct tda18218_priv *priv, u8 reg, u8 val)
	{
	return tda18218_wr_regs(priv, reg, &val, 1);
	}

	/* read single register */

	static int tda18218_rd_reg(struct tda18218_priv priv, u8 reg, u8 val)
	{
	return tda18218_rd_regs(priv, reg, val, 1);
	}

	static int tda18218_set_params(struct dvb_frontend *fe)
	{
	struct tda18218_priv *priv = fe->tuner_priv;
	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
	u32 bw = c->bandwidth_hz;
	int ret;
	u8 buf[3], i, BP_Filter, LP_Fc;
	u32 LO_Frac;
	/* TODO: find out correct AGC algorithm */
	u8 agc[][2] = {
	{ R20_AGC11, 0x60 },
	{ R23_AGC21, 0x02 },
	{ R20_AGC11, 0xa0 },
	{ R23_AGC21, 0x09 },
	{ R20_AGC11, 0xe0 },
	{ R23_AGC21, 0x0c },
	{ R20_AGC11, 0x40 },
	{ R23_AGC21, 0x01 },
	{ R20_AGC11, 0x80 },
	{ R23_AGC21, 0x08 },
	{ R20_AGC11, 0xc0 },
	{ R23_AGC21, 0x0b },
	{ R24_AGC22, 0x1c },
	{ R24_AGC22, 0x0c },
	};

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

	/* low-pass filter cut-off frequency */
	if (bw <= 6000000) {
	LP_Fc = 0;
	priv->if_frequency = 3000000;
	} else if (bw <= 7000000) {
	LP_Fc = 1;
	priv->if_frequency = 3500000;
	} else {
	LP_Fc = 2;
	priv->if_frequency = 4000000;
	}

	LO_Frac = c->frequency + priv->if_frequency;

	/* band-pass filter */
	if (LO_Frac < 188000000)
	BP_Filter = 3;
	else if (LO_Frac < 253000000)
	BP_Filter = 4;
	else if (LO_Frac < 343000000)
	BP_Filter = 5;
	else
	BP_Filter = 6;

	buf[0] = (priv->regs[R1A_IF1] & ~7) \| BP_Filter; /* BP_Filter */
	buf[1] = (priv->regs[R1B_IF2] & ~3) \| LP_Fc; /* LP_Fc */
	buf[2] = priv->regs[R1C_AGC2B];
	ret = tda18218_wr_regs(priv, R1A_IF1, buf, 3);
	if (ret)
	goto error;

	buf[0] = (LO_Frac / 1000) >> 12; /* LO_Frac_0 */
	buf[1] = (LO_Frac / 1000) >> 4; /* LO_Frac_1 */
	buf[2] = (LO_Frac / 1000) << 4 \|
	(priv->regs[R0C_MD5] & 0x0f); /* LO_Frac_2 */
	ret = tda18218_wr_regs(priv, R0A_MD3, buf, 3);
	if (ret)
	goto error;

	buf[0] = priv->regs[R0F_MD8] \| (1 << 6); /* Freq_prog_Start */
	ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
	if (ret)
	goto error;

	buf[0] = priv->regs[R0F_MD8] & ~(1 << 6); /* Freq_prog_Start */
	ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
	if (ret)
	goto error;

	/* trigger AGC */
	for (i = 0; i < ARRAY_SIZE(agc); i++) {
	ret = tda18218_wr_reg(priv, agc[i][0], agc[i][1]);
	if (ret)
	goto error;
	}

	error:
	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

	if (ret)
	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

	return ret;
	}

	static int tda18218_get_if_frequency(struct dvb_frontend fe, u32 frequency)
	{
	struct tda18218_priv *priv = fe->tuner_priv;
	*frequency = priv->if_frequency;
	dev_dbg(&priv->i2c->dev, "%s: if_frequency=%d\n", __func__, *frequency);
	return 0;
	}

	static int tda18218_sleep(struct dvb_frontend *fe)
	{
	struct tda18218_priv *priv = fe->tuner_priv;
	int ret;

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

	/* standby */
	ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] \| (1 << 0));

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

	if (ret)
	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

	return ret;
	}

	static int tda18218_init(struct dvb_frontend *fe)
	{
	struct tda18218_priv *priv = fe->tuner_priv;
	int ret;

	/* TODO: calibrations */

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

	ret = tda18218_wr_regs(priv, R00_ID, priv->regs, TDA18218_NUM_REGS);

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

	if (ret)
	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

	return ret;
	}

	static int tda18218_release(struct dvb_frontend *fe)
	{
	kfree(fe->tuner_priv);
	fe->tuner_priv = NULL;
	return 0;
	}

	static const struct dvb_tuner_ops tda18218_tuner_ops = {
	.info = {
	.name = "NXP TDA18218",

	.frequency_min = 174000000,
	.frequency_max = 864000000,
	.frequency_step = 1000,
	},

	.release = tda18218_release,
	.init = tda18218_init,
	.sleep = tda18218_sleep,

	.set_params = tda18218_set_params,

	.get_if_frequency = tda18218_get_if_frequency,
	};

	struct dvb_frontend tda18218_attach(struct dvb_frontend fe,
	struct i2c_adapter i2c, struct tda18218_config cfg)
	{
	struct tda18218_priv *priv = NULL;
	u8 val;
	int ret;
	/* chip default registers values */
	static u8 def_regs[] = {
	0xc0, 0x88, 0x00, 0x8e, 0x03, 0x00, 0x00, 0xd0, 0x00, 0x40,
	0x00, 0x00, 0x07, 0xff, 0x84, 0x09, 0x00, 0x13, 0x00, 0x00,
	0x01, 0x84, 0x09, 0xf0, 0x19, 0x0a, 0x8e, 0x69, 0x98, 0x01,
	0x00, 0x58, 0x10, 0x40, 0x8c, 0x00, 0x0c, 0x48, 0x85, 0xc9,
	0xa7, 0x00, 0x00, 0x00, 0x30, 0x81, 0x80, 0x00, 0x39, 0x00,
	0x8a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf6, 0xf6
	};

	priv = kzalloc(sizeof(struct tda18218_priv), GFP_KERNEL);
	if (priv == NULL)
	return NULL;

	priv->cfg = cfg;
	priv->i2c = i2c;
	fe->tuner_priv = priv;

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

	/* check if the tuner is there */
	ret = tda18218_rd_reg(priv, R00_ID, &val);
	if (!ret)
	dev_dbg(&priv->i2c->dev, "%s: chip id=%02x\n", __func__, val);
	if (ret \|\| val != def_regs[R00_ID]) {
	kfree(priv);
	return NULL;
	}

	dev_info(&priv->i2c->dev,
	"%s: NXP TDA18218HN successfully identified\n",
	KBUILD_MODNAME);

	memcpy(&fe->ops.tuner_ops, &tda18218_tuner_ops,
	sizeof(struct dvb_tuner_ops));
	memcpy(priv->regs, def_regs, sizeof(def_regs));

	/* loop-through enabled chip default register values */
	if (priv->cfg->loop_through) {
	priv->regs[R17_PD1] = 0xb0;
	priv->regs[R18_PD2] = 0x59;
	}

	/* standby */
	ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] \| (1 << 0));
	if (ret)
	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);

	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */

	return fe;
	}
	EXPORT_SYMBOL(tda18218_attach);

	MODULE_DESCRIPTION("NXP TDA18218HN silicon tuner driver");
	MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
	MODULE_LICENSE("GPL");